Okayama University Medical SchoolActa Medica Okayama0386-300X8052026High Accuracy of Pelvic Tilt Measurement Using Three-Dimensional Planning Software: A Validation Study Using Dry Bone Models289298ENYukiKomutaDivision of Orthopedic Surgery, Graduate School of Medical and Dental Sciences, Niigata UniversityNorioImaiDivision of Comprehensive Musculoskeletal Medicine, Graduate School of Medical and Dental Sciences, Niigata UniversityDaisukeHommaDivision of Orthopedic Surgery, Graduate School of Medical and Dental Sciences, Niigata UniversityKazuhisaFunayamaDivision of Legal Medicine, Graduate School of Medical and Dental Sciences, Niigata UniversityYukiHiranoDivision of Orthopedic Surgery, Graduate School of Medical and Dental Sciences, Niigata UniversityYojiHorigomeDivision of Comprehensive Musculoskeletal Medicine, Graduate School of Medical and Dental Sciences, Niigata UniversityIzumiMinatoDepartment of Orthopedic Surgery, Niigata Rinko HospitalHiroyukiKawashimaDivision of Orthopedic Surgery, Graduate School of Medical and Dental Sciences, Niigata UniversityOriginal Article10.18926/AMO/71338The “CR Alignment” function was recently introduced in ZedHip®, the hip joint module of ZedView®, to evaluate pelvic tilt in non-supine positions via two-dimensional (2D)‒3D matching using radiographs. However, its ccuracy has not been validated. This study therefore evaluated the accuracy of pelvic tilt measurements using the CR Alignment function in dry pelvic bone specimens. Two cadaveric pelvic bone models were placed in nine orientations (anterior/posterior tilt and left/right rotation). Both radiographic and CT images were acquired in each position. In Study 1, pelvic tilt measured directly from CT images was defined as the “true value.” Three observers used the CR Alignment function to calculate pelvic tilt on radiographs, and measurement errors were determined relative to the true values. In Study 2, measurement errors were compared between matched (same position) and mismatched (different position) imaging. In Study 1, the mean measurement error was 1.28±0.64°. Intra- and interobserver intraclass correlation coefficients were 0.996-0.998 and 0.997, respectively. In Study 2, the mean errors were 1.20±0.88° (matched) and 1.32±1.03° (mismatched). This software exhibited high accuracy and reproducibility in 2D‒3D matching of pelvic tilt, with lower variability under matched acquisition, demonstrating its utility for pre- and postoperative assessment in joint arthroplasty.No potential conflict of interest relevant to this article was reported.WileyActa Medica Okayama2751-1219592026Proton‐Radiation‐Tolerant Silicon Photonic Charge Sensor for Spacecraft Applicationse70208ENWataruTakahamaDepartment of Physics and Electronics, Osaka Metropolitan UniversityKoseiOtsukaDepartment of Physics and Electronics, Osaka Metropolitan UniversityAyumiIshiharaDepartment of Physics and Electronics, Osaka Metropolitan UniversityRikutoHojoDepartment of Space Systems Engineering, Kyushu Institute of TechnologyTomofumiMogamiElectrostaticEngineering DEPT, Kasuga Denki INCKazuhiroToyodaDepartment of Space Systems Engineering, Kyushu Institute of TechnologyKohtakuSuzukiResearch and Development, The Wakasa Wan Energy Research CenterYasushiTakahashiFaculty of Environmental, Life, Natural Science and Technology,Okayama UniversitySilicon waveguides are promising platforms for spacecraft potential sensing owing to their compactness and immunity to electromagnetic interference. However, proton-induced optical absorption in operating silicon waveguides has not been quantitatively clarified, despite their direct exposure to the space radiation environment during spacecraft operation. Here, we present a systematic elucidation of proton-radiation effects on a photonic charge sensor based on silicon photonic crystal waveguides. During proton irradiation at 20 keV, we quantitatively evaluate the increase in optical absorption under device operation and find that a fluence of 1.0 ×1014 cm− 2 induces an additional absorption coefficient of approximately 0.41 cm− 1 . We further demonstrate that the sensor retains its ability to measure spacecraft potential even after exposure to a high proton fluence of 1.0 ×1015 cm− 2 , confirming its intrinsic radiation tolerance. These results establish the radiation robustness of silicon-waveguide- based sensing mechanisms and provide the first quantitative basis for implementing photonic charge sensors in radiation-rich spacecraft environments.
No potential conflict of interest relevant to this article was reported.WileyActa Medica Okayama8756-758X2026Fatigue Life Evaluation Using the Damage‐Equivalent Strain for 7075‐T6 Aluminum Alloy Under Bending and Torsion Bending VibrationsENJunjiSakamotoFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityNaoyaTadaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityTakeshiUemoriFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityThe vibrations caused by external factors (such as fluids) or internal factors often pose strength-related problems in mechanical and structural components. Although several studies have investigated the material fatigue characteristics during vibration, reports on complex vibration modes such as torsion bending are limited. In this study, we addressed this gap by conducting experiments and finite element analyses on I- and L-shaped aluminum alloy specimens under bending and torsion bending vibrations, respectively. We established a reliable method to estimate the strain at the notch by utilizing the strain measured at a position outside the notch and a ratio derived from finite element analysis. This method allows for accurate assessment of the critical strain history without interfering with crack observation. Using the strain range at the crack initiation site effectively unified the fatigue life evaluation for both specimens.No potential conflict of interest relevant to this article was reported.American Society for MicrobiologyActa Medica Okayama0099-22402026Interaction with the N-acetylgalactosamine moiety facilitates pore formation by Cry4Aa toxin, thereby increasing its toxicitye00714-26ENMohammad Tofazzal HossainHowladerDepartment of Entomology, Bangladesh Agricultural UniversityTaiyoTsutsuiApplied Chemistry and Biotechnology Program, School of Engineering, Okayama UniversityKouichiSaitoGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityTohruHayakawaApplied Chemistry and Biotechnology Program, School of Engineering, Okayama UniversityCry4Aa is a mosquito-larvicidal toxin produced by Bacillus thuringiensis serovar israelensis. Cry4Aa exhibits a characteristic architecture comprising three domains (I, II, and III) and functions as a pore-forming toxin, consistent with many previously reported insecticidal Cry toxins. However, the mechanism preceding pore formation by Cry4Aa, including receptor recognition, remains to be elucidated. The present study examined the potential involvement of sugar moieties in the Cry4Aa mode of action, with a particular focus on the process of pore formation. Cry4Aa and the sugar N-acetylgalactosamine exhibited considerably increased binding affinity. Furthermore, N-acetylgalactosamine treatment significantly enhanced the toxicity of Cry4Aa against Culex pipiens mosquito larvae. In the presence of N-acetylgalactosamine, the binding of Cry4Aa to phosphatidylcholine liposomes increased by 1.4-fold. The presence of this sugar did not affect the single-channel conductance of Cry4Aa pores formed in artificial lipid bilayers; however, it did appear to increase the number of Cry4Aa pores per designated area. In silico molecular docking analysis revealed promising binding sites within the cavity, surrounded by the Cry4Aa domains. These results suggest that the interaction of Cry4Aa with N-acetylgalactosamine moieties is a vital step in the process of pore formation. This interaction may induce a conformational change in the Cry4Aa molecule that facilitates its insertion into the target membrane.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama2238-7854452026Enhancement of mechanical properties in a cast hypereutectic Al–Si alloy via rapid cooling in heated mold continuous casting485494ENShuheiTakeuchiGraduate School of Environment, Life, Natural Science and Technology, Okayama UniversityShotaNakagawaUACJ CorporationYoshifumiShinzatoUACJ CorporationTadashiMinodaUACJ CorporationNaotakaOhtsukaUACJ CorporationMitsuhiroOkayasuDepartment of Mechanical and Systems Engineering, Okayama UniversityTo enhance mechanical properties in cast hypereutectic Al–Si alloys, Al–14.5Si samples were produced by the heated mold continuous casting (HMC). The HMC process was conducted under unidirectional solidification at cooling rates (CRs) ranging from 4.6 × 10−1 to 1.3 × 103 K/s, which were obtained by controlling the casting speed (CS). The microstructure basically consisted of α-Al dendrite, Al–Si eutectic and primary Si, while their area fractions (fα-Al, fe, and fp-Si) varied depending on the CR. At the low CR of 4.6 × 10−1 K/s, their area fractions were as follows: fα-Al = 0.2%, fe = 97.3%, and fp-Si = 2.5%, which is the typical microstructural morphology of a hypereutectic Al-Si alloy. In contrast, at the high CR of 1.3 × 103 K/s, those area fractions were altered to fα-Al = 32.3% and fe = 67.7%, while primary Si was strongly suppressed (fp-Si ≈ 0%) despite the hypereutectic Al–14.5Si alloy. Moreover, at the high CR, the aluminum matrix appears to exhibit a nearly uniform crystal orientation along <101>. These microstructural changes may be related not only to high CR but also the difference in growth kinetics between primary Si and α-Al dendrites. Accordingly, an apparent eutectic composition shifted from 12.6 to 19.7 wt% Si. The atypical microstructural formation led to a significant improvement in the tensile properties: the ultimate tensile strength of 400 MPa and fracture strain of 17%. These tensile properties are more than twice those of the conventional cast hypereutectic Al–14.5Si alloy.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0376-73887572026Multi-criteria evaluation of graphene oxide nanofiltration membranes for decaffeination125992ENYihanTianSchool of Materials Science and Engineering, University of New South WalesTongxiLinSchool of Materials Science and Engineering, University of New South WalesYutaNishinaResearch Institute for Interdisciplinary Science, Okayama UniversityXiaojunRenSchool of Materials Science and Engineering, University of New South WalesRakeshJoshiSchool of Materials Science and Engineering, University of New South WalesNanofiltration (NF) offers a promising low-energy approach for producing decaffeinated instant coffee, while requires membranes that balance caffeine removal, water permeance, and retention of key coffee matrix compounds. Here, graphene oxide membranes (GOMs) were modified by sodium alginate (SA) intercalation, Ca2+ crosslinking, and their combined strategy to tune nanochannel structure and separation performance. The results show that membrane modification does not follow a simple monotonic trend; instead, small structural and chemical changes generate competing effects on permeance and selectivity through coupled transport, adsorption, and confinement mechanisms. To identify the most suitable membrane, a multi-criteria evaluation framework (MCEF) combining entropy weighting and TOPSIS was established using five key performance indicators: caffeine removal, flavour-related marker retention index, choline retention, water permeance, and concentration increase. This framework identified CGSM-1 as the best-performing flat membrane, which also showed promising performance in hollow-fibre form. In coffee filtration tests, CGSM-1 reduced caffeine concentration from 24.64 to 12.95 μg/mg, corresponding to a 47.4% reduction, while retaining measurable levels of HMF, trigonelline, NMP, and choline. These findings demonstrate the potential of engineered GOMs for selective caffeine reduction in coffee liquor and provide a practical evaluation strategy for membrane-based decaffeination.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0360-31992702026The effect of end-gas auto-ignition flame properties on the knocking intensity of a dual-fuel hydrogen engine157103ENRikuOkamotoGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityNobuyukiKawaharaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityYoshimitsuKobashiFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityThis study sought to elucidate the mechanism governing PRE-mixed mixture ignition in end-gas region (PREMIER) combustion in a dual-fuel hydrogen engine. Both knocking and PREMIER combustion are induced by end-gas auto-ignition, but differ in terms of the subsequent development of pressure waves. Knocking is accompanied by strong waves, whereas PREMIER combustion is characterized by the absence of, or very few, such waves. End-gas auto-ignition of hydrogen–air mixtures was visualized while in-cylinder pressure was measured using an optical compression and expansion machine. The visualization data indicate that KI increased as the spread velocity of the end-gas auto-ignition front rose. That velocity remained below 100 m/s during PREMIER combustion, but attained approximately 400 m/s in severe knocking cycles. The theory proposed by Bradley was used to evaluate the experimental results, and two dimensionless parameters, ξ and ε, were estimated. The ξ-ε diagram showed a distinct transition from PREMIER combustion to knocking. (150 words).No potential conflict of interest relevant to this article was reported.WileyActa Medica Okayama2699-9307662026NUAK2 Inhibition Enhances Macromolecular Drug Delivery in a 3D Fibrotic Model of the Pancreatic Tumor Microenvironmente202500237ENMisakiNakamuraDepartment of Pharmaceutical Biomedicine Graduate School of Medicine Dentistry and Pharmaceutical Sciences, Okayama UniversityHiroyoshi Y.TanakaDepartment of Pharmaceutical Biomedicine Graduate School of Medicine Dentistry and Pharmaceutical Sciences, Okayama UniversityMayuOhiraDepartment of Pharmaceutical Biomedicine Graduate School of Medicine Dentistry and Pharmaceutical Sciences, Okayama UniversityHarukoOhta‐OkanoDepartment of Pharmaceutical Biomedicine Graduate School of Medicine Dentistry and Pharmaceutical Sciences, Okayama UniversityReikaNakamuraDepartment of Pharmaceutical Biomedicine Graduate School of Medicine Dentistry and Pharmaceutical Sciences, Okayama UniversityYuSenoDepartment of Pharmaceutical Biomedicine Graduate School of Medicine Dentistry and Pharmaceutical Sciences, Okayama UniversitySaayaYaraDepartment of Pharmaceutical Biomedicine Graduate School of Medicine Dentistry and Pharmaceutical Sciences, Okayama UniversitySakuraFujitaDepartment of Pharmaceutical Biomedicine Graduate School of Medicine Dentistry and Pharmaceutical Sciences, Okayama UniversityDaichiShibataDepartment of Pharmaceutical Biomedicine Graduate School of Medicine Dentistry and Pharmaceutical Sciences, Okayama UniversityMasayaYamamotoDepartment of Materials Processing Graduate School of Engineering, Tohoku UniversityShinichiToyookaDepartment of General Thoracic Surgery and Breast and Endocrinological Surgery Graduate School of Medicine Dentistry and Pharmaceutical Sciences, Okayama UniversityKensukeOsadaDepartment of Molecular Imaging and Theranostics Institute for Quantum Medical Science, National Institutes for Quantum Sciences and Technology (QST) HoracioCabralDepartment of Bioengineering Graduate School of Engineering, The University of TokyoAtsushiMasamuneDivision of Gastroenterology Graduate School of Medicine, Tohoku UniversityMitsunobu R.KanoDepartment of Pharmaceutical Biomedicine Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityPancreatic ductal adenocarcinoma (PDAC) features a fibrotic tumor microenvironment that impedes drug delivery and significantly limits the successful clinical application of nanomedicines. Targeting signaling in pancreatic stellate cells (PSCs), which drive fibrosis via excessive secretion of extracellular matrix proteins such as collagen I, may be useful in overcoming this fibrotic barrier. The AMPK-related kinases NUAK1/2 have recently gained interest as promoters of fibrosis, but whether they play a profibrotic role in PSCs remains unknown. Here, patient PSCs are used to assess NUAK1/2 involvement in the PDAC fibrotic barrier. Leveraging a 3D cell culture model of PDAC fibrosis, the effect of targeting NUAK1/2 on the permeability of macromolecular dextrans of various sizes, as well as physiologically relevant macromolecules, albumin and IgG, and clinical nanomedicines, Doxil and Abraxane, is investigated. NUAK1/2 inhibition is shown to diminish collagen I to enhance macromolecular permeability, via a mechanism independent of established pathways involving transforming growth factor-β (TGFβ) and yes-associated protein (YAP). Through isoform-specific knockdown, predominant NUAK2 involvement is demonstrated. Mechanistically, actin stress fiber regulation by NUAK2 is shown to be important. Altogether, these results show in vitro that NUAK2 promotes fibrotic signaling in PSCs and may be targeted to enhance macromolecular drug delivery in PDAC.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama1939-59812026Micro-segregation of Primary Si in ADC14 (Al–17Si–4Cu) Alloy Produced by Unidirectional Continuous CastingENShuheiTakeuchiGraduate School of Environment, Life, Natural Science and Technology, Okayama UniversityShotaNakagawaUACJ CorporationYoshifumiShinzatoUACJ CorporationTadashiMinodaUACJ CorporationNaotakaOhtsukaUACJ CorporationMitsuhiroOkayasuDepartment of Mechanical and Systems Engineering, Okayama UniversityAn upgrading approach for hypereutectic Al–Si alloys was investigated through controlled segregation of Si using a unidirectional casting process. The precipitation behavior and spatial distribution of primary Si in the hypereutectic ADC14 (Al–17Si–4Cu) alloy were systematically examined at different casting speeds (0.06, 1.9, and 10 mm/s). Microstructural observations revealed that high casting speed suppresses primary Si formation due to rapid solidification, whereas intermediate speed leads to a relatively uniform distribution of primary Si. In contrast, low casting speed combined with a holding period for 2 min promotes pronounced segregation and coarsening of primary Si in localized regions. Energy-dispersive X-ray spectroscopy analysis confirmed significant fluctuations in Si concentration along the casting direction, particularly after process interruption. Based on these results, a preliminary upgrading process was proposed, involving the selective removal of Si-enriched regions followed by remelting. This approach resulted in a reduction of Si content to approximately 13.9 wt.%, corresponding to a decrease of about 3%. The results demonstrate that controlling solidification behavior to induce phase separation provides a promising and energy-efficient strategy for upgrading recycled Al–Si alloys.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0001-86863582026Revisiting particle formation beyond classical nucleation: A unified classification framework for nonclassical pathways104018ENYuyaIidaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversitySatoshiWatanabeDepartment of Chemical Science and Engineering, Kyoto UniversityParticle formation is pervasive in both nature and technology, shaping environmental and biological phenomena while underpinning a broad range of industrial products. A mechanistic understanding of particle formation is therefore important both for fundamental science and for the design of particle properties. It is now well established that particle formation can proceed through diverse pathways beyond classical one-step nucleation. At the same time, the proliferation of reported nonclassical pathways has blurred the distinctions among mechanistic categories and obscured their underlying relationships. In this review, we revisit the development of concepts in particle formation pathways and present a unified perspective on this increasingly complex mechanistic landscape. To this end, we classify the nonclassical features of particle formation along three conceptual axes: stepwise transitions between phases or phase-like fluctuations, chemically driven formation of structural units, and aggregation-dominant nucleation and growth processes. This framework places diverse pathways within a common three-dimensional space referenced to classical nucleation, providing a basis for comparing apparently distinct mechanisms within a single picture. We further discuss representative theoretical descriptions in relation to these axes and outline future challenges.No potential conflict of interest relevant to this article was reported.Oxford University Press (OUP)Acta Medica Okayama0449-30606742026Enhancement of antioxidant function in various organs in mice using combined thermal and radon inhalation treatment538549ENShogoMiyanagaGraduate School of Health Sciences, Okayama UniversityAyumiTanakaGraduate School of Health Sciences, Okayama UniversityReijuTakenakaGraduate School of Health Sciences, Okayama UniversityShotaNaoeNingyo-toge Environmental Engineering Center, Japan Atomic Energy AgencyShunaGotoGraduate School of Health Sciences, Okayama UniversityMitsukiNaganoGraduate School of Health Sciences, Okayama UniversityKotaroTanoGraduate School of Health Sciences, Okayama UniversityNorieKanzakiNingyo-toge Environmental Engineering Center, Japan Atomic Energy AgencyAkihiroSakodaNingyo-toge Environmental Engineering Center, Japan Atomic Energy AgencyKiyonoriYamaokaFaculty of Health Sciences, Okayama UniversityTakahiroKataokaFaculty of Health Sciences, Okayama UniversityEnhancing antioxidant function is a key strategy for preventing and treating oxidative stress-related diseases. Radon inhalation and thermal treatment (TT) increase the levels of antioxidant enzymes, such as superoxide dismutase (SOD). The positive effects of this combination on pain-related diseases have been reported; however, few studies have elucidated the underlying mechanisms. In this study, we examined the enhancement of antioxidant function in various organs of mice subjected to combined TT and radon inhalation. The mice were placed in an incubator once daily for 40 min at 38.5 ± 0.5°C and treated for 1, 3 and 7 days. The mice then inhaled radon at a concentration of 2000 Bq/m3 for 24 h. The characteristic changes in antioxidant function following combined TT and radon inhalation could be categorized into four groups: (i) increased antioxidant function in the brain and colon; (ii) increased or decreased antioxidant function, as observed in the kidney; (iii) decreased antioxidant function, such as in the lungs and (iv) no changes, such as in the small intestine, spleen, pancreas, heart, liver and stomach. Additionally, SOD may be the antioxidant enzyme most sensitive to combined TT and radon treatment. Collectively, the combined treatment may be the most effective in activating antioxidative functions in the brain and colon. This study provides new insights into the effects of combined TT and radon inhalation.No potential conflict of interest relevant to this article was reported.Frontiers Media SAActa Medica Okayama2296-4185142026High horizontal force and lateral force transmission induced by the twist of the Achilles tendon1874501ENShotaEnomotoGraduate School of Education, Okayama UniversityKohtaItoArtificial Intelligence Research Center, National Institute of Advanced Industrial Science and Technology (AIST)The Achilles tendon—the largest and strongest of the many tendons in the human body—consists of subtendons arising from each head of the triceps surae. These subtendons run helically and intertwine to form a twisted three-dimensional structure. More than a century has passed since the twisted structure of the Achilles tendon was first described, and numerous studies have investigated its functional morphology. However, it remains unclear how the presence or degree of twist affects the mechanical function of the lower limbs. Here, using finite element models of the Achilles tendon with and without twist, we show that the presence and degree of twist can modulate the forces transmitted from muscle to skeleton in a complex manner. In contrast to the model without twist, the twisted models clearly exhibit anterolaterally directed horizontal forces at the distal end under a simple proximal tensile load. The lateral and anterior components reach approximately 101 N and 63 N, respectively. Furthermore, the twisted structure induces inter-subtendon force transmission, and the magnitude of the transmitted force increases with increasing degree of twist. These results indicate that the uniaxial contractile force generated by the triceps surae is transformed into triaxial forces by the twisted Achilles tendon and is redistributed in a complex three-dimensional manner through inter-subtendon interactions.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0016-23614292027Mechanism of Enhanced Heat Release in Spray Combustion of a Methanol–DME Blended Fuel140693ENYoshimitsuKobashiFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityShodaiMakinoGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityMasakuniNambaGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityNobuyukiKawaharaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityKatsuyoshiAsakaTechnical Management Division, Carbon Neutral Technology Department, DAIHATSU INFINEARTH MFG. CO., LTD.KazuyukiKobayashiTechnical Management Division, Carbon Neutral Technology Department, DAIHATSU INFINEARTH MFG. CO., LTD.This paper investigates the spray combustion characteristics of a methanol–DME blended fuel with a DME mole fraction of 0.57 in a constant volume vessel. The rate of heat release (ROHR) was evaluated using pressure-based heat release analysis. The results show that the methanol–DME blended fuel requires a longer injection duration due to the lower LHV (lower heating value), but it exhibits a shorter combustion duration than conventional diesel fuel, together with a higher ROHR normalized by the injection LHV rate and a shorter afterburning duration. To elucidate the relationship between the spray combustion processes and the ROHR characteristics, the spray flame was visualized using schlieren and OH chemiluminescence imaging techniques. In addition, a one-dimensional simulation based on a diesel jet model was conducted to evaluate the distributions of the equivalence ratio. These analyses reveal that the lower theoretical air–fuel ratio, attributed to the oxygenated nature of the methanol–DME blended fuel, reduces the equivalence ratio within the spray, promoting earlier formation of near-stoichiometric mixtures. As a result, the ROHR reaches and sustains its maximum earlier during mixing-controlled combustion, and fuel consumption is enhanced during afterburning.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama1756-46461262025Proteome analysis reveals the molecular mechanisms of fucoxanthin-induced apoptosis in glial cells PC12 after nanoencapsulation106710ENChunyanWangSchool of Food Science, Henan Institute of Science and TechnologyXinxinMaSchool of Food Science, Henan Institute of Science and TechnologyYoshimasaNakamuraGraduate School of Environmental and Life Science, Okayama UniversityHangQiSKL of Marine Food Processing & Safety Control, National Engineering Research Center of Seafood, Collaborative Innovation Center of Seafood Deep Processing, School of Food Science and Technology, Dalian Polytechnic UniversityFucoxanthin (FX) is a natural pigment belonging to the xanthophyll carotenoid, which has been proven to have inhibitory effects on glioblastoma. In our previous study, nano-FX was fabricated through whey protein and flaxseed gum co-encapsulated for improved stability and glial cell (PC12) inhibitory activity of FX. To investigate the molecular mechanisms of FX-induced apoptosis in PC12 after nanoencapsulation, proteomics analysis based on TMT technology was performed. Protein profiles in PC12 were determined after 0 (Control), 8 (L_Treat), and 24 (H_Treat) μg/mL nano-FX intervention. Results indicated 78 differential abundant proteins (DAPs) linked to the cytotoxicity of nano-FX could be potential biomarkers. GO and KEGG analysis revealed altered proteasome and NF-kappa B/MAPK/TNF. Proteins involved in cell proliferation were downregulated, while proteins response to autophagy and apoptosis were upregulated. The multiple mechanisms involved in the anti-tumor activity of nano-FX will provide a reference for the development of FX high value-added functional foods.No potential conflict of interest relevant to this article was reported.American Physiological SocietyActa Medica Okayama0022-307713542026Characteristics of cross-modal negative BOLD responses in the human sensory subcortex and cortex747759ENToshikazuMiyataDivision of Sensory and Cognitive Brain Mapping, Department of System Neuroscience, National Institute for Physiological SciencesMasakiFukunagaSection of Brain Function Information, National Institute for Physiological SciencesJunxiangLuoDivision of Sensory and Cognitive Brain Mapping, Department of System Neuroscience, National Institute for Physiological SciencesIsaoYokoiNational Institute for Physiological SciencesTetsuyaYamamotoSection of Brain Function Information, National Institute for Physiological SciencesAyumiYoshiokaSection of Brain Function Information, National Institute for Physiological SciencesJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityTomoyoMoritaCenter for Information and Neural Networks (CiNet), Advanced ICT Research Institute, National Institute of Information and Communications Technology (NICT)HiromasaTakemuraDivision of Sensory and Cognitive Brain Mapping, Department of System Neuroscience, National Institute for Physiological SciencesFunctional magnetic resonance imaging (fMRI) is a noninvasive method for measuring human brain activity based on blood oxygenation level-dependent (BOLD) responses. Although many studies have reported positive BOLD responses evoked by sensory stimuli, others have reported negative BOLD responses (NBRs) in the sensory cortex when stimuli from different sensory modalities are presented (i.e., cross-modal NBRs). We conducted an fMRI experiment to better understand the characteristics of cross-modal NBRs in subcortical and cortical regions. Auditory and visual stimuli were presented unilaterally to one ear and to either the left or right visual field, respectively. The lateral geniculate nucleus and medial geniculate nucleus did not show a significant cross-modal NBR. In contrast, the primary auditory cortex showed a significant cross-modal NBR when visual stimuli were presented in either the contralateral or ipsilateral visual fields. Finally, we found that the cross-modal NBR in the early visual cortex was highly variable across subjects and did not exhibit consistent trends. However, each subject’s data exhibited considerable split-half reliability. Our results suggest that cross-modal NBR in the auditory cortex likely reflects mechanisms such as interhemispheric suppression, rather than those coordinated within the same hemisphere.<br>
NEW & NOTEWORTHY This study demonstrated that the human primary auditory cortex showed a significant cross-modal negative BOLD response bilaterally, regardless of the visual field in which the visual stimuli were presented. This result suggests that the cross-modal negative BOLD response is not an epiphenomenon of visual cortex activation predominantly observed in the contralateral hemisphere, but is more likely to reflect interhemispheric suppression mechanisms.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0753-33221942026Elucidation of mechanisms underlying the therapeutic effects of cordycepin on pulmonary hypertension, with a focus on cell senescence and gut microbiota118923ENGaopengLiDepartment of Cardiovascular Physiology, Faculty of Medicine, Kagawa UniversityZhixinZhaoInner Mongolia Key Laboratory of Dairy Biotechnology and Engineering, Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural UniversityMitsuhiroMachitaniDivision of Cancer Stem Cell, National Cancer Center Research InstituteRyouIshikawaDepartment of Diagnostic Pathology, Kagawa University HospitalKaoriIshikawaDepartment of General Medicine, Kagawa University HospitalNaoyaYokotaDepartment of General Thoracic Surgery, Faculty of Medicine, Kagawa UniversityReijiHabaDepartment of Diagnostic Pathology, Kagawa University HospitalKazufumiNakamuraCenter for Advanced Heart Failure, Okayama University HospitalZhihongSunInner Mongolia Key Laboratory of Dairy Biotechnology and Engineering, Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural UniversityLin-HaiKuraharaDepartment of Cardiovascular Physiology, Faculty of Medicine, Kagawa UniversityKatsuyaHiranoDepartment of Cardiovascular Physiology, Faculty of Medicine, Kagawa UniversityIntroduction: Pulmonary hypertension (PH) is a progressive cardiopulmonary disorder characterized by excessive pulmonary vascular remodeling and aberrant proliferation of pulmonary artery smooth muscle cells (PASMCs). Emerging evidence suggests that gut microbiota dysbiosis contributes to PH development. Cordycepin, a natural adenosine analogue derived from Cordyceps militaris, has demonstrated antiproliferative and microbiota-modulating properties; however, its mechanism of action in PH remains unclear.<br>
Objective: Elucidate the mechanisms underlying the therapeutic effects of cordycepin on PH, focusing on cellular senescence and gut microbiota.<br>
Methods: The effects of cordycepin on PH pathology were investigated by transcriptome analysis of PASMCs from patients, and metagenomic analysis of rodent PH models. Cellular senescence was analyzed in lung tissue from p16Ink4a-CreERT2 reporter mice and in rat bone marrow-derived macrophages (BMDMs).<br>
Results: RNA sequencing analysis revealed activation of p53 signaling by cordycepin in PASMCs. Cordycepin suppressed CDK1 expression and TERT phosphorylation at threonine 249. It ameliorated vascular and cardiac remodeling in PH rat and mouse models. Cordycepin induced M1-like macrophage senescence in p16 Ink4a reporter mice lungs and rat BMDMs. Cordycepin significantly reshaped the gut microbiota, increasing beneficial genera (e.g. Alistipes and Acetatifactor) and reducing proinflammatory taxa (e.g., Ruminococcus), with modulating key metabolic pathways, including short-chain fatty acid, tryptophan, and vitamin K2 metabolism.<br>
Conclusion: Cordycepin exerts multi-target therapeutic effects in PH by inhibiting PASMC proliferation via the p53–CDK1/pTERT axis, modulating gut microbiota-linked immunometabolism and induces proinflammatory macrophage senescence. These findings support cordycepin as a promising candidate for PH therapies targeting the vascular, immune, and gut–lung axes.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama1867-10712026A novel robot for CT-guided bone needle insertion with a rotational drilling and force-feedback speed control mechanism: preliminary evaluation in swineENYusukeMatsuiDepartment of Radiology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityTakaoHirakiDepartment of Radiology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityYutaKimuraDepartment of Radiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityTakanoriSasakiCollaborative Research Center for OMIC, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama UniversityRyutaroMatsuuraDepartment of Radiological Technology, Faculty of Health Sciences, Okayama UniversityKojiTomitaDepartment of Radiology, Medical Development Field, Okayama UniversityNoriyukiUmakoshiDepartment of Radiology, Medical Development Field, Okayama UniversitySoichiroOkamotoDepartment of Radiology, Medical Development Field, Okayama UniversityKazuakiMunetomoDepartment of Radiology, Medical Development Field, Okayama UniversityFumiyoHigakiDepartment of Radiology, Medical Development Field, Okayama UniversityJunSakuraiCenter for Innovative Clinical Medicine, Okayama University HospitalToshihiroIguchiDepartment of Radiological Technology, Faculty of Health Sciences, Okayama UniversityAtsushiNakazawaFaculty of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityKiyoshiMatsumiyaDepartment of Medical Technology, Faculty of Life Science, Okayama University of ScienceTakayukiMatsunoFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityTetsushiKamegawaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityPurpose To evaluate the feasibility and accuracy of computed tomography (CT)-guided needle insertion into swine bones by using a novel robotic system capable of rotational drilling.<br>
Materials and methods This was an animal experiment using three swine. A remote-controlled robot equipped with a rotational drilling and force-feedback insertion speed control mechanism was developed for bone needle insertion. Using the robot, CT-guided insertion of a 10-gauge bone access needle was attempted in the lumbar vertebrae, ilia, and femora six times each. Needle insertion accuracy was evaluated using the angle error, which is defined as the difference between the predetermined and post-insertion needle angles on axial and sagittal CT images. The time required for needle insertion was measured. The angle error and time required for needle insertion were compared among the bones using the Kruskal–Wallis test. Adverse events were also evaluated.<br>
Results Robotic bone needle insertion was successful in all attempts. The median axial and sagittal angle errors were 0.21 and 0.21° for the lumbar vertebrae, 0.32 and 0.13° for the ilia, and 0.65 and 0.25° for the femora, respectively. Axial angle errors were significantly different among the bone types (p = 0.038). The time required for needle insertion was 23.6, 21.3, and 59.7 s for the lumbar vertebrae, ilia, and femora, respectively. Time was significantly different among bone types (p = 0.017). No adverse events were observed.<br>
Conclusion CT-guided bone needle insertion using a robot equipped with a rotational drilling and force-feedback insertion speed control mechanism was feasible and accurate in swine.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0378-38202882026Hydrogen-lean two-stage upgrading of highly acidic palm acid oil via decoupled acid reduction and deoxygenation108478ENHirofumiNogeGraduate school of education, Okayama universityChiyuNakanoDepartment of comprehensive technical solutions, Okayama UniversityYoshieUenoDepartment of Food and Nutrition, Faculty of Home Economics, Kyoto Women's UniversityWira JazairYahyaInstitute for Sustainable Transport HICoE, University Teknologi MalaysiaHasannuddinAbd KadirFaculty of Mechanical Engineering, Universiti Teknologi MARASachiMasunagaDepartment of comprehensive technical solutions, Okayama UniversityUpgrading highly acidic waste lipids into liquid hydrocarbons under limited hydrogen availability remains challenging due to catalyst deactivation, excessive cracking, and poor process stability. Palm acid oil (PAO), characterized by extremely high free fatty acid content, represents a particularly demanding feedstock. This study proposes a hydrogen-lean two-stage upgrading strategy that decouples acid value (AV) reduction from hydrocarbon formation through staged reactor operation. In the first stage, batch pretreatment under low hydrogen pressure (initial 0.1 MPa) enabled rapid apparent AV reduction. However, increasing temperature promoted thermally driven degradation, highlighting intrinsic limitations of single-stage severity intensification. Methanol-assisted pretreatment further decreased AV mainly through esterification and formation of oxygenated intermediates. In the second stage, hydrogen-free fixed-bed upgrading over oxide-based catalysts exhibited a distinct operating window near 365 °C, where stable condensed liquid recoveries of 50–60 wt% were obtained. Deoxygenation proceeded predominantly via decarbonylation/decarboxylation pathways. Among the catalysts investigated, ZrO₂–Co showed superior stability and lower residual AV. Overall, reactor staging enabled AV reductions exceeding 90% within 1.5–2 h while maintaining stable liquid recovery, demonstrating an effective upgrading strategy for highly acidic waste lipids under hydrogen-lean conditions.No potential conflict of interest relevant to this article was reported.WileyActa Medica Okayama1347-903211742026Roles of TIF1β in Leukemic Stem Cell Through SETDB1-Dependent and Independent Mechanisms896903ENMarikoMoriiGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityShoKubotaDepartment of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityGoroSashidaLaboratory of Transcriptional Regulation in Leukemogenesis, International Research Center for Medical Sciences, Kumamoto UniversityTIF1β/TRIM28/KAP1 has been recognized as a scaffold protein that partners with KRAB-ZFPs and heterochromatin complexes to enforce gene silencing. In embryonic and pluripotent stem cells, it maintains self-renewal by silencing endogenous retroelements through the establishment of heterochromatin. While these canonical functions have been extensively examined in embryonic stem (ES) cells, accumulating evidence also highlights its diverse contributions to cancer biology. We herein focused on the oncogenic role of TIF1β in leukemic progression, contrasting this with its physiological roles in hematopoietic stem cell maintenance, differentiation, and immune regulation, thereby providing a comparative perspective on H3K9 methyltransferase SETDB1-dependent and -independent mechanisms. TIF1β-mediated epigenetic plasticity was recently shown to establish a leukemic chromatin environment for promoting oncogenic transcriptional programs while repressing lineage-differentiation regulators, which drives leukemic progression in a context-dependent manner. This review summarizes the dual role of TIF1β as a chromatin modulator, functioning both as a canonical transcriptional co-repressor and as a context-dependent co-activator, and also discusses how these modalities cooperate to sustain leukemic stem cell programs.No potential conflict of interest relevant to this article was reported.Royal Society of Chemistry (RSC)Acta Medica Okayama2633-0679712026Programmable synthesis of alkaloidal frameworks integrating Michael acceptor generates covalent probes for targeting POLE3 in HBV replication105119ENNobutoKanekoDepartment of Chemistry, Graduate School of Science, The University of TokyoMisaoHimenoDepartment of Developmental Medical Sciences, Graduate School of Medicine, The University of TokyoYuhiKobayashiDepartment of Chemistry, Graduate School of Science, The University of TokyoRyoTanifujiDepartment of Chemistry, Graduate School of Science, The University of TokyoHirokiKubotaDepartment of Applied Chemistry, Graduate School of Engineering, Tokyo University of Agriculture and TechnologyHarukiMizoguchiGraduate School of Natural Science and Technology, Okayama UniversityMakotoMuroiCentre for Sustainable Resource Science, RIKENTakehiroSuzukiCentre for Sustainable Resource Science, RIKENMasayaSugiyamaDepartment of Viral Pathogenesis and Control, National Institute of Global Health and Medicine, Japan Institute for Health SecurityNaoshiDohmaeCentre for Sustainable Resource Science, RIKENHiroyukiOsadaCentre for Sustainable Resource Science, RIKENTaketomoKidoLaboratory of Cell Growth and Differentiation, Institute for Quantitative Biosciences, The University of TokyoAtsushiMiyajimaLaboratory of Cell Growth and Differentiation, Institute for Quantitative Biosciences, The University of TokyoHirokiOguriDepartment of Chemistry, Graduate School of Science, The University of TokyoThe growing need for effective HBV treatments and lead compounds with novel mechanisms prompted us to explore synthetic strategies for generating skeletally diverse alkaloidal Michael acceptors. Our approach uniquely embeds Michael acceptors directly within multicyclic alkaloid-inspired frameworks, exploiting the azepinoindole scaffold—a privileged structure in indole alkaloids. A single-step assembly between the versatile intermediate 13 with methyl propiolate 14 or its derivatives enabled the rapid and divergent synthesis of six alkaloidal Michael acceptors (15–20). This strategy facilitated systematic diversification of three-dimensional functional group arrangements and precise tuning of the electronic and steric properties of the embedded α,β-unsaturated carbonyl moieties. The optimal hit 15 inhibited hepatitis B surface antigen (HBsAg) production with an IC50 of 2.48 μM and significantly reduced levels of covalently closed circular DNA (cccDNA), the master template of HBV. Unlike existing nucleoside/nucleotide-based anti-HBV drugs that primarily inhibit reverse transcription, the alkaloidal Michael acceptor 15 suppressed both cccDNA and relaxed circular DNA (rcDNA) levels, suggesting a potential pathway toward a functional HBV cure. Our study also streamlined the target identification by leveraging the covalent binding properties of the Michael acceptors and the operational simplicity of biotin- or fluorescent-tag attachment via a pre-installed alkyne moiety. Competitive pull-down experiments identified several potential target proteins, involving DNA polymerase epsilon subunit 3 (POLE3). Notably, the alkaloidal Michael acceptor 15 was demonstrated to covalently modify Cys51 in POLE3, providing new insights into virus–host interactions and opening novel avenues for targeted anti-HBV therapies. This approach represents a significant advance beyond traditional screening methods and underscores the potential of skeletally diverse alkaloidal Michael acceptors in antiviral drug development.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama0924-090X11482026Basin boundary metamorphoses due to changes in accessible boundary orbits in passive dynamic walking595ENKotaOkamotoDepartment of Aeronautics and Astronautics, Graduate School of Engineering, Kyoto UniversityNozomiAkashiGraduate School of Informatics, Kyoto UniversityIppeiObayashinterdisciplinary Education and Research Field, Okayama UniversityHiroshiKokubuDepartment of Mathematics, Graduate School of Science, Kyoto UniversityJames A.YorkeDepartments of Mathematics and Physics, Institute for Physical Science and Technology, University of MarylandShinyaAoiDepartment of Mechanical Science and Bioengineering, Graduate School of Engineering Science, The University of OsakaPassive dynamic walking is a mechanical system that walks down a shallow slope without any input or control, and is a useful tool for understanding the dynamic properties of walking. This system has a wide variety of periodic solutions through bifurcations depending on the slope angle, resulting in chaotic attractors and fractal basin boundaries. In addition, basin boundary metamorphoses occur at certain slope angles, where the boundaries of the basin of attraction change abruptly, but the mechanism underlying this phenomenon remains largely unclear. A well-known dynamical system, the Hénon map, exhibits similar properties, and its basin boundary metamorphoses have been explained in terms of changes in accessible boundary orbits caused by intersections of manifolds associated with bifurcating solutions. Inspired by this framework, we propose a hypothesis for the mechanism of basin boundary metamorphoses in passive dynamic walking by introducing the concept of accessible boundary orbits and verify it numerically. Our results provide new insights into the governing dynamics of walking and contribute to a deeper understanding of nonlinear phenomena in locomotion systems.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama2589-00422942026Human iPSC cardiomyocyte patch transplantation modifies extracellular matrix and fibroblast behavior after myocardial infarction115341ENKosukeTorigataCuorips Inc.RyoheiMatsuuraMax Planck Institute for Heart and Lung Research, Laboratory for Cell Polarity and OrganogenesisFumiyaNagatomoDepartment of Mechanical Engineering, School of Engineering, The University of TokyoMoeThihaDepartment of Pathophysiology and Drug Discovery, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Okayama UniversityTakaoHikitaDepartment of Pathophysiology and Drug Discovery, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Okayama UniversityHirokoIseokaDepartment of Cardiovascular Surgery, Osaka University Graduate School of MedicineHiromitsuTakagiDaiichi Sankyo Co., Ltd.UichiKoshimizuDaiichi Sankyo Co., Ltd.HirokiSakakimaDepartment of Mechanical Engineering, School of Engineering, The University of TokyoSatoshiIzumiDepartment of Mechanical Engineering, School of Engineering, The University of TokyoAsukaHatanoDepartment of Mechanical Engineering, School of Engineering, The University of TokyoThomasBraunMaxPlanck Institute for Heart and Lung Research, Department of Cardiac Development and RemodelingYoshikiSawaDepartment of Cardiovascular Surgery, Osaka University Graduate School of MedicineShigeruMiyagawaDepartment of Cardiovascular Surgery, Osaka University Graduate School of MedicineMasanoriNakayamaDepartment of Pathophysiology and Drug Discovery, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Okayama UniversityMyocardial infarction (MI) followed by chronic heart failure is the main cause of mortality of heart diseases. Although reparative cell transplantation therapies with pluripotent stem cell-derived cardiomyocytes (CMs) represent a promising therapeutic strategy, molecular mechanisms of the therapy remain elusive. Here, we show that transplantation of the human induced pluripotent stem cell (hiPSC)-derived CM patch onto the damaged heart after MI increases the ratio of collagen type I against collagen type III to modulate alignment of the collagen fibers at the infarcted zone. As a result, tissue elasticity of the heart is improved, and fibrosis at the remote zone is reduced. Mechanistically, we find that hiPSC-derived CM patches secrete TGF-β1, directly inducing collagen type I production in fibroblasts but not collagen type III. Our results suggest the direct effect of the transplanted CM patch on the cardiac fibroblasts to improve elasticity of the damaged heart, resulting in functional recovery after MI.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X8022026Involvement of ADAM12 in TGF-β1-Induced Proliferation of Rheumatoid Arthritis Synovial Fibroblasts7583ENDetingLinDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesMasahiroHoritaDepartment of Orthopaedic Surgery, Faculty of Medical Development Field, Okayama UniversityMasahitoWatanabeDepartment of Orthopaedic Surgery, Muscat Orthopaedic ClinicJoeHaseiMedical Information and Assistive Technology Development, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityTakashiOhtsukiMedical Technology, Graduate School of Health Sciences, Okayama UniversityNoriakiOtsukaDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesChinatsuIchikawaDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesNoriyukiShimizuDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesShuichiNaniwaDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesToshifumiOzakiDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesKeiichiroNishidaDivision of Chronic Pain Medicine and Division of Comprehensive Rheumatology, Locomotive Pain Center, Faculty of Medical Development Field, Okayama UniversityOriginal Article10.18926/AMO/70450A disintegrin and metalloproteinase 12 (ADAM12) is known to be involved in chondrocyte proliferation and is upregulated in the synovial tissue of osteoarthritis (OA). However, the underlying mechanisms of ADAM12 on rheumatoid arthritis (RA) synovial cell proliferation remain unknown. Here, we investigated the role of ADAM12 in the proliferation of RA synovial fibroblasts (RASFs). The expression and localization of ADAM12 in RA synovial tissues were examined by immunohistochemistry and compared with OA and healthy control (HC) synovial tissues. The effect of inflammatory cytokines (TNF-α, TGF-β1, and PDGF-BB) on ADAM12 expression in RASFs from RA patients was examined by real-time RT-PCR. The effect of ADAM12 knock-down by ADAM12 siRNA and ADAM12 overexpression on cell proliferation of RASFs were examined by WST-1 assay. ADAM12 was identified predominantly in RA synovial tissue rather than OA and HC synovial tissues. Stimulation with TGF-β1 upregulated the expression of ADAM12 and cell proliferation of RASFs. ADAM12 siRNA suppressed TGF-β1-induced cell proliferation of RASFs, while ADAM12 overexpression promoted the cell proliferation of RASFs. These findings demonstrate that ADAM12 may have a key role in TGF-β1-induced cell proliferation of synovial fibroblasts in patients with RA.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0143-41601352026Regulation of brain-specific kinases 1 and 2 (BRSK1/2) by Ca2+/calmodulin103134ENNaoyukiWashidaMoeKataokaDepartment of Applied Chemistry and Biotechnology, Faculty of Engineering, Okayama UniversityAnna R.BrunApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityUryuTakezakiApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityKoHijikawaDepartment of Applied Chemistry and Biotechnology, Faculty of Engineering, Okayama UniversityHarukiYamauchiApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversitySatomiOhtsukaApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityMasakiMagariApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityRyoMorishitaCellFree Sciences Co., Ltd.HiroshiTokumitsuApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityWe conducted a genome-wide calmodulin (CaM) interaction screening of 462 GST-fused human protein kinases to identify novel CaM-dependent protein kinases (CaMKs). In addition to known CaMKs, including myosin light chain kinases, CaMK2γ, and death-associated kinase 2, we identified the brain-specific protein kinase 2 (BRSK2, also known as SAD-A) as a novel CaM interactant. Proximity biotinylation and CaM–sepharose chromatography assays revealed that rat BRSK isoforms (BRSK1/2) interact with CaM in a Ca2+-dependent manner in vitro. We found that CaM suppresses the activation-loop phosphorylation of BRSK1 (at Thr189) and BRSK2 (at Thr175) by liver kinase B1 (LKB1), an activating kinase, in a Ca2+-dependent manner (IC50 of ∼7 µM), thereby inhibiting BRSK activation. LKB1-catalyzed phosphorylation of the catalytic domain mutant of BRSK1 (residues 1–294) at Thr189 was suppressed by the addition of Ca2+/CaM, consistent with direct CaM binding of the kinase domain, as well as wild-type BRSK1. We confirmed that the LKB1 activity was not directly suppressed by Ca2+/CaM, supporting the hypothesis that the direct interaction of Ca2+/CaM with the kinase domain blocks the phosphorylation/activation of BRSK1/2 by LKB1. The kinase activity and PP2Cα-catalyzed dephosphorylation of LKB1-phosphorylated BRSK1 were not altered by Ca2+/CaM, although it was demonstrated to bind to Ca2+/CaM like that of unphosphorylated BRSK1. This unrecognized mechanism of BRSK1/2 regulation, involving the direct role of Ca2+/CaM binding, which inhibits phosphorylation/activation by LKB1, may open a new Ca2+ signal transduction pathway in neurons.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0923-181111912025Big data-driven target identification by machine learning: DRD2 as a therapeutic target for psoriasis917ENTakashiSakaiDepartment of Dermatology, Faculty of Medicine, Oita UniversityRyusukeSawadaDepartment of Pharmacology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesOtohaIchinoseDepartment of Bioscience and Bioinformatics, Faculty of Computer Science and Systems Engineering, Kyushu Institute of TechnologyTakeshiTerabayashiDepartment of Pharmacology, Faculty of Medicine, Oita UniversityYutakaHatanoDepartment of Dermatology, Faculty of Medicine, Oita UniversityYoshihiroYamanishiDepartment of Complex Systems Science, Graduate School of Informatics, Nagoya UniversityToshimasaIshizakiDepartment of Pharmacology, Faculty of Medicine, Oita UniversityBackground: The development of medical treatments has traditionally relied on researchers leveraging scientific knowledge to hypothesize disease mechanisms and identify therapeutic agents. However, the depletion of novel therapeutic targets has become a significant challenge, resulting in stagnation within pharmaceutical research.<br>
Objective: To address the scarcity of therapeutic targets, we developed a machine learning (ML)-based system capable of predicting therapeutic target molecules for diseases. To validate its utility, we applied this system to psoriasis, aiming to identify novel treatment strategies.<br>
Methods: Our approach utilized a large clinical database to calculate reporting odds ratios for all drugs associated with the prevention of diseases of interest. We identified target proteins by analyzing large chemical structure databases to discover proteins commonly associated with preventive drug candidates. Experimental validation was conducted by administering a predicted therapeutic candidate in an imiquimod-induced psoriasis mouse model.<br>
Results: The ML-based predictions identified drugs for Parkinson’s disease as potential preventive candidates for psoriasis. Further analysis highlighted dopamine receptor D2 (DRD2) as a therapeutic target. Administration of a DRD2 agonist alleviated psoriasis symptoms in mice, evidenced by the downregulation of mRNA expression in the IL-17 pathway and reduced serum tumor necrosis factor-α levels.<br>
Conclusion: This study demonstrates the utility of a novel ML-based system for identifying therapeutic targets, as shown by its successful application in uncovering the role of DRD2 in psoriasis. Beyond psoriasis, this system offers significant potential for exploring pathological mechanisms and discovering therapeutic targets across various diseases.No potential conflict of interest relevant to this article was reported.Japan Society of Mechanical EngineersActa Medica Okayama1880-55582012025Numerical analysis validating the standard k-epsilon model for the kinetic energy of turbulence subjected to weak but long-lasting wind tunnel blockage accelerationJFST0004ENAkiraONOGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityHirokiSUZUKIGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityToshinoriKOUCHIGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityKentoTANAKAGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityThe aim of this study is to investigate the effect of weak but prolonged mean flow accelerations, such as those observed in wind tunnel blockage acceleration, on free-stream turbulence. Specifically, this research aims to validate a model previously developed based on the k-epsilon model. To test this model, the study focuses on scenarios where the turbulence under acceleration is steady and isotropic, since the model suggests that this type of acceleration has no effect on the turbulent kinetic energy. To examine this suggestion, the turbulence within a periodic box was analyzed using large-eddy simulation (LES) based on the conventional Smagorinsky model framework. The numerical analysis is based on a method that conserves velocity fluctuation intensities. The results show that while high rate of acceleration deviates turbulent kinetic energy, low rate acceleration has hardly any effect on turbulent kinetic energy, enstrophy, pressure fluctuation, relative pressure fluctuation intensity, and higher-order statistics of a velocity fluctuation. These results validate the accuracy of the model proposed in the previous studies. These results were obtained by focusing on differences in Reynolds numbers and the spatial scale of the forcing.No potential conflict of interest relevant to this article was reported.Japan Society of Mechanical EngineersActa Medica Okayama2187-97451252025Examining OpenFOAM-based LES analysis in terms of inviscid energy conservation and viscous turbulence decay25-00095ENHirokiSUZUKIGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityKentoTANAKAGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityToshinoriKOUCHIGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityThe present study examines an OpenFOAM-based LES analysis from the viewpoints of inviscid energy conservation and viscous turbulence decay. The Smagorinsky model is employed as the sub-grid scale (SGS) model, and a two-dimensional periodic analytical solution and a three-dimensional periodic Taylor-Green vortex (TGV) are employed to represent inviscid flows. The analytical relationship for the kinetic energy K, dK/dt = 0, with t as the dimensionless time, is utilized to validate the OpenFOAM results. For the viscous flow case, the TGV flow in a three-dimensional periodic cubic domain is adopted, and its turbulence kinetic energy distribution is compared with that obtained by a spectral method to examine the analysis. The OpenFOAM-based analysis exhibits energy conservation error in flows that should ideally conserve energy. For the two-dimensional flow, this error decreases with increasing grid resolution N. However, in the three-dimensional flow, the error does not improve even with higher N. In the three-dimensional TGV flow, the turbulence kinetic energy predicted by OpenFOAM exhibits a strong agreement with that from the spectral method when a standard constant value of the Smagorinsky model is employed and the mesh is sufficiently refined. Conversely, for a condition of relatively coarse mesh, the decay characteristics of turbulent kinetic energy deviate from those of the spectral method, and a higher constant value of the Smagorinsky model than the default value becomes necessary to reproduce comparable results. These results suggests that even in LES simulations where highly accurate conservation laws are not satisfied, adjusting the model constants so that the predicted values match experimental or numerical reference data can improve the apparent reliability of the turbulent kinetic energy in the decaying turbulence.No potential conflict of interest relevant to this article was reported.Institute of Electrical and Electronics Engineers (IEEE)Acta Medica Okayama2169-3536142026FEM-Based Design and Characterization of a Millimeter-Scale Piezoelectric Resonance Force Sensor1796017970ENAotoYamazakiDepartment of Mechanical Engineering, Toyohashi University of TechnologyTakumaAkidukiDepartment of Mechanical Engineering, Toyohashi University of TechnologyAtsuoHonnaRiccoh Company Ltd.MichiteruKitazakiDepartment of Computer Science and Engineering, Toyohashi University of TechnologyTomoakiMashimoGraduate School of Natural Science and Technology, Okayama UniversityThis paper presents a millimeter-scale piezoelectric effect-based force sensor that uses the change in its resonant frequency as the detection principle for high sensitivity and a wide measurement range. Such characteristics are suited for robot hand applications that not only detect small forces but also handle large payloads. We develop a methodology to estimate the relationship between applied force and resonant frequency shift by combining classical contact theory and finite element method (FEM) analysis. Although this relationship is non-linear, the designability of sensitivity and measurement range is demonstrated by the simulation. The simulation results based on the method are verified, showing good agreement with the experimental results. The static characteristics, including sensitivity, standard deviation, and resolution, are evaluated using prototype sensors with characteristic lengths ranging from 1 mm to 4 mm. The 4-mm model has a measurement range of 77 mN to 300 N, and the smallest model, which is one of the smallest force sensors suitable for practical implementation, has a measurement range of 9 mN to 20 N.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama2590-1230272025Inscribed-type spherical speed reducer with uniform reduction ratio in all directions106742ENSeiyaNaramuraFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityKoichiTonegawaGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversitySoShimookaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityTomoakiYanoFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityAkioGofukuOkayama Prefectural UniversityNagayoshiKasashimaNational Institute of Advanced Industrial Science and TechnologyTetsushiKamegawaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityA spherical motor is an actuator that can generate rotational motion about all three orthogonal axes. However, it is difficult to obtain high output torque from most electromagnetic spherical motors, primarily due to limitations inherent in electromagnetic actuators, such as restricted magnetic force and thermal constraints. Since its torque cannot be increased using planar gears, spherical speed reducers that transmit rotational torque along three orthogonal axes through sphere-to-sphere contact are required. One major limitation of conventional spherical speed reducers is that their size increases significantly as the reduction ratio becomes higher. To address this issue, we propose a novel inscribed-type spherical speed reducer, in which the deceleration mechanism is integrated within the output sphere. This configuration enables a more compact design, reducing the overall size to approximately half that of conventional designs. To predict the angular velocity and transmitted torque, theoretical models for the rotation and torque transmission of the speed reducer were developed. According to the proposed model, the reduction ratio of the spherical speed reducer is 1/3. To verify the validity of these models, experiments were conducted to measure angular velocity and torque. The theoretical results agreed well with the experimental results. In addition, the theoretical torque exhibited an average relative error of 1.63 % compared to the experimental result. Therefore, it was confirmed that the rotation and torque transmission models were valid. These results demonstrate that a reduction ratio can be obtained in all directions of the 3-DOF of the spherical speed reducer, unlike conventional 1-DOF reducers.No potential conflict of interest relevant to this article was reported.Japanese Society of TribologistsActa Medica Okayama1881-21982042025Tribological Properties of Amorphous-SiC-Based Coatings on Al2O3 Substrates in Normal Saline212219ENTadashiShiotaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityDaikiTaniyaGraduate School of Natural Science and Technology, Okayama UniversityKazumaShimazakiGraduate School of Natural Science and Technology, Okayama UniversityChiyuNakanoDepartment of Comprehensive Technical Solutions, Okayama UniversityYuyaOmiyaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityMasahiroFujiiFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityAmorphous SiC (a-SiC)-based coatings containing not only Si–C bonds but also C–Si–O, C–C, and Si–O2 bonds were deposited on Al2O3 substrates via pulsed laser deposition. Sliding tests using SiC ceramic balls in normal saline revealed that the coating exhibited a low friction coefficient of 0.05-0.06 at a shorter running-in process than SiC bulk ceramic plates. The specific wear rate of the coating was also lower than that of the SiC plate. Reactive molecular dynamics simulations revealed that the C–Si–O bonds in the coating facilitated the generation of Si–O units, which contained Si–O bonds but no Si-C bonds, through tribochemical reactions with water, resulting in superior tribological properties in normal saline compared to those of SiC plates. These findings demonstrate that a-SiC-based coatings containing C–Si–O bonds are promising as low-friction and low-wear coatings for biomedical implants such as ceramic joint prostheses.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama2168-81841812026Central Serous Chorioretinopathy in Parallel With Onset and Relapses of Minimal Change Nephrotic Syndrome: A 28-Year Case Follow-Upe102426ENToshihikoMatsuoDepartment of Ophthalmology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityTakehiroTanakaDepartment of Pathology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama UniversityJunWadaDepartment of Nephrology, Rheumatology, Endocrinology, and Metabolism, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama UniversityCentral serous chorioretinopathy is an idiopathic disease that manifests as one or several localized, small, dome-shaped serous retinal detachments on fundus examination. The pathophysiology involves fluid leakage from the choroidal capillaries, known as the choriocapillaris, into the subretinal space through sites of damage in the retinal pigment epithelium. This case report discusses the underlying causes of central serous chorioretinopathy-like findings in minimal change nephrotic syndrome.<br>
<br>
The patient was a 33-year-old woman who developed nephrotic syndrome that was confirmed to be minimal change disease by renal biopsy. She experienced two major relapses of nephrotic syndrome at the ages of 36 and 41 years. She also had a minor relapse at the age of 37 years, five months after the first major relapse at the age of 36 years, as well as four additional minor relapses at the ages of 44, 46, 50, and 51 years. The onset of central serous chorioretinopathy-like manifestations, which were localized to the left eye, occurred three months after the initial onset of nephrotic syndrome at the age of 33 years. Two subsequent episodes of relapse of central serous chorioretinopathy-like manifestations were observed in both eyes at intervals of five months and one month, respectively, after major relapses of nephrotic syndrome at the ages of 36 and 41 years. Thereafter, she did not develop further central serous chorioretinopathy-like manifestations.<br>
<br>
She discontinued oral prednisolone at the age of 54 years and experienced no further relapses of nephrotic syndrome through her latest visit at the age of 61 years. She maintained normal renal function and good visual acuity in both eyes. The long-term, consistent temporal association between episodes of central serous chorioretinopathy and the onset and relapses of minimal change nephrotic syndrome is strongly supported by longitudinal clinical observations spanning 28 years. This parallel course suggests a possible shared pathophysiological mechanism or common triggering factors underlying both diseases.No potential conflict of interest relevant to this article was reported.Royal Society of Chemistry (RSC)Acta Medica Okayama2050-750X2026Multi-step mechanisms of early phospholipid hydrolysis and mineralisation unveiled through combined quantum chemical calculations and experimental analysisENKeisukeShibataDepartment of Materials Science, Waseda UniversityTakahumiShiotaniDepartment of Resources and Environmental Engineering, Waseda UniversityYunhaoChenDepartment of Materials Science, Waseda UniversityReinaKuriharaDepartment of Resources and Environmental Engineering, Waseda UniversityKatsunoriYamaguchiDepartment of Resources and Environmental Engineering, Waseda UniversityEmilio SatoshiHaraDepartment of Advanced International and Information Dentistry, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical SciencesNílsonKunioshiDepartment of Materials Science, Waseda UniversityPhospholipids play key roles in bone formation, with phosphatidylserine (PS) reportedly inducing more rapid mineralisation than phosphatidylcholine (PC); however, the underlying mechanisms remains unclear. This study investigated PS and PC mineralisation using experimental methods and computational chemistry. The stationary points in the potential energy surfaces of the reactions were preliminarily found using a neural network potential (PreFerred Potential in Matlantis) capable of predicting the interaction energies for arbitrary combinations of atoms, and then refined through density functional theory calculations (Gaussian16, at the B3LYP/6-31G(d,p) level of theory). When hydrolysis reactions were assumed to be the initial step in the mineralisation of phospholipids, the results were consistent with empirical analysis. PS was found to be more easily hydrolised than PC, primarily owing to the presence of a labile proton in the NH3+ group of serine that facilitates proton transfer, enhancing hydrolysis of PS at lower energy thresholds. Specifically, when a single phospholipid was considered, three distinct hydrolysis routes were identified: between serine (or choline) and phosphate, between glycerol and phosphate, and between an aliphatic carbon chain and the glycerol backbone. In particular, the initial steps of hydrolysis involved the formation of a pentavalent phosphate intermediate. When calculations were performed with two adjacent phospholipid molecules, the loosely bound proton (H+) in the NH3+ group could be readily transferred either to the P–O bond linking serine to the phosphate group; or to the P–O bond connecting the phosphate to glycerol in a neighboring PS6 molecule. These findings reveal the important roles of serine NH3+ in facilitating hydrolysis of PS, and provide insights for designing novel molecules to accelerate bone regeneration.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama2590-1230292026Unified 2D polygon-based CAM framework integrating tool path generation, machinability evaluation, and cutting-force simulation108948ENKazukiKanekoFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityHirotoTakayasuGraduate School of Science and Engineering, Ibaraki UniversityAtsuyaSuzukiMechanical Systems Engineering Program, Okayama UniversityHiroyukiKodamaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityThis study proposes a unified two-dimensional (2D) polygon-based computer-aided manufacturing (CAM) framework that enables tool path generation, machinability evaluation, material removal simulation, and cutting-force prediction within a single computational environment. The proposed method represents three-dimensional geometries as aggregates of orthogonal 2D polygon sets, obtained by slicing the model in the xy-, yz-, and zx-parallel planes and superposing the three polygonal datasets. A novel convolutional offsetting algorithm is developed to perform three-dimensional inflation and shrinkage by incorporating adjacent cross-sectional relationships, thereby achieving accurate 3D offsets independent of the slicing orientation. The inflated 2D polygons are directly utilized to generate contour and scanning tool paths, and sequential inflation–shrinkage analysis enables visualization of unmachinable regions for tool accessibility evaluation. Furthermore, the framework integrates an instantaneous cutting force model that accurately predicts the cutting force waveform by detecting intersections between the cutting edge points and 2D polygon aggregations. The system is experimentally validated via ball-end milling. The results demonstrate that tool paths can be generated in under one minute using only a CPU. Furthermore, the simulated cutting forces closely align with experimental measurements. These findings demonstrate that the proposed 2D polygon-based framework provides an efficient and extensible foundation for integrating mechanical simulation and tool-path generation.No potential conflict of interest relevant to this article was reported.American Chemical Society (ACS)Acta Medica Okayama0006-296064202025Characterization of Autonomous and Ca2+/Calmodulin-Dependent Activities of CaMKK Isoforms In Vitro and in Mouse Tissues43094317ENSatomiOhtsukaApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYerunChenApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityMasakiMagariApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityTeruhikoIshikawaDepartment of Science Education, Graduate School of Education, Okayama UniversityHiroyukiSakagamiDepartment of Anatomy, Kitasato University School of MedicineFutoshiSuizuClinical Examination Department, Kagawa Prefectural University of Health SciencesHiroshiTokumitsuApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityCa2+/CaM-dependent protein kinase kinase (CaMKK) phosphorylates and activates downstream kinases, including CaMKI, CaMKIV, PKB, and AMPK, regulating various cellular functions such as neuronal morphogenesis, metabolic control, and pathophysiological pathways, such as cancer progression. CaMKKα/1 is tightly regulated by an autoinhibitory mechanism. CaMKKβ/2 activity is highly Ca2+/CaM-independent (autonomous activity) in vitro and Ca2+/CaM-dependent in cultured cells. Whether these two activity states of CaMKKβ/2 exist in vivo and the detailed regulatory mechanisms for the transition of both activity states remain unclear due to the difficulty in distinguishing the two activity states. In this study, we detected Ca2+-dependent and autonomous CaMKK activity in HeLa cells and successfully separated both activity states of CaMKKβ/2 in mouse brain and testis extracts using a recently developed CaMKK inhibitor (TIM-063)-coupled sepharose, which binds to the catalytic domain in the active state but not in the autoinhibited state. Furthermore, lambda protein phosphatase treatment converted the Ca2+/CaM-dependent form to the autonomous form of CaMKKβ/2, which was not affected by Ala mutation of Ser128, Ser132, and Ser136. The two activity forms of CaMKKβ/2 had equivalent Ca2+/CaM-binding ability. The findings demonstrate the presence of autonomous and Ca2+/CaM-dependent forms of CaMKKβ/2 independently in mouse tissues and cultured cells. The transition of these states of CaMKKβ/2 may be dynamically regulated by the phosphorylation/dephosphorylation of serine residues in the N-terminal regulatory domain.No potential conflict of interest relevant to this article was reported.Institute of Electrical and Electronics Engineers (IEEE)Acta Medica Okayama2169-3536132025Adaptive Topological Mapping With Free Area-Based Node Deletion for Autonomous Mobile RobotsENHarukaOzakiGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityYuichiroTodaGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityNaokiMasuyamaGraduate School of Informatics, Osaka Metropolitan UniversityKaiFujiGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityTakayukiMatsunoGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityThis paper proposes an adaptive topological map building method, called Adaptive Resonance Theory-based Topological Clustering with Different Topologies (ATC-DT), for autonomous mobile robots using 3D point cloud data. ATC-DT framework integrates a novel node deletion mechanism that detects layout changes through free area detection. This allows the robot to update topological maps dynamically, removing outdated nodes caused by environmental changes. Experiments in real environments validate the ability of the method to perform global path planning, free area estimation, and adaptive navigation. The approach significantly improves navigation performance by improving map relevance and reducing redundancy of paths.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0010-94521942026Increasing visual uncertainty modulates multisensory decision-making5062ENXiangfuYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityWeipingYangDepartment of Psychology, Faculty of Education, Hubei UniversityYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYoshimichiEjimaGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityThe brain integrates and transforms information from multiple senses to make optimal decisions, a process that is critical for navigating complex environments with perceptual uncertainty. Despite a growing consensus that individuals adapt flexibly to uncertain sensory input, whether increasing visual uncertainty influences the decision process itself or other, non-decision sensory processes during multisensory decision-making are unclear. Here, an audiovisual categorization task was used to examine the responses of human participants (N = 30) to visual and audiovisual stimuli under low-, medium-, and high-uncertainty conditions. Modeling the behavioral data using a drift‒diffusion model indicated that increased visual uncertainty in the audiovisual context decreased the evidence accumulation rate but had no effect on non-decision processes. Electrophysiological recordings confirmed and expanded upon these results: increased visual uncertainty in the audiovisual context reduced the amplitude during the late decision-making stage (300–380 msec) but had no effect on the amplitude during the early sensory encoding stage (140–220 msec). More importantly, electroencephalography analyses revealed that audiovisual integration in the early sensory encoding stage occurred robustly across all visual uncertainty conditions, whereas audiovisual integration in the late stage occurred only under medium and high visual uncertainty conditions. This study demonstrated that increased visual uncertainty modulates the decision process itself rather than early sensory encoding during multisensory decision-making. Moreover, multisensory integration strategies dynamically adapt to increasing visual uncertainty by engaging different mechanisms to maintain effective decision-making.No potential conflict of interest relevant to this article was reported.Fuji Technology Press Ltd.Acta Medica Okayama1883-80493762025Directed Poisoning Attacks on FRIT in Adaptive Cruise Control13921399ENTaichiIkezakiFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityKenjiSawadaGraduate school of Mechanical Engineering, The University of OsakaOsamuKanekoGraduate School of Informatics and Engineering, The University of Electro-CommunicationsRecent advances in connected-vehicle technologies have enabled the large-scale collection of driving data, facilitating the deployment of data-driven control schemes. Although these methods offer advantages by eliminating the need for explicit modeling, they also introduce vulnerabilities due to their reliance on stored data. This study investigates a class of targeted data poisoning attacks on fictitious reference iterative tuning, a widely used data-driven controller tuning approach. We present a method that allows an adversary to influence closed-loop dynamics by manipulating the training data so that the resulting controller behavior matches a maliciously defined reference response. This strategy differs from conventional poisoning attacks, which aim only to the degrade control performance. Instead, it enables deliberate alteration of control characteristics such as overshoot and convergence time. The proposed attack is formulated as a constrained optimization problem under bounded tampering signals. Through a numerical study involving adaptive cruise control with stop functionality, we show that minor data modifications, indistinguishable from sensor noise, can cause significant degradation in control behavior. These findings highlight the need for robust security mechanisms in data-driven control implementation.No potential conflict of interest relevant to this article was reported.Japan Society of Mechanical EngineersActa Medica Okayama1880-55662022025DNS analysis on the correlation between local burning velocity and flame displacement speed of turbulent premixed flames25-00212ENKazuyaTSUBOIFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityThe local burning velocity and flame displacement speed are the major properties of premixed flames. The local burning velocity, which is the instantaneous quantity based on the local consumption rate of the unburnt mixture, is considered to be the most appropriate burning velocity in terms of the definition. The local burning velocity can be evaluated theoretically and numerically; however, it is almost impossible to obtain it experimentally using the current technology of measurement. The flame displacement speed can be evaluated more easily than the local burning velocity and compared with the flame displacement speed obtained from experiments. However, the local burning velocity and flame displacement speed have been discussed separately in turbulent premixed flames. In this study, to clarify the relation between the local burning velocity and the flame displacement speed, numerical analyses were performed using the DNS database of statistically steady and fully developed turbulent premixed flames with different density ratios of the unburnt mixture to the burnt product and with different Lewis numbers. It was found that for different density ratios, the local burning velocity was little sensitive to the flame displacement speed in any case under the unity Lewis number. This means the correlation between the local burning velocity and the flame displacement speed is little affected by the dilation of a flame. For different Lewis numbers, the correlation between the local burning velocity and the flame displacement speed was negative in Le = 0.8, and positive in Le = 1.2. This can be explained by the effect of the Lewis number on the local burning velocity, and the flame displacement speed was little affected by the Lewis number in the correlation between the local burning velocity and the flame displacement speed.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama2452-199X572026Robust adhesion between solid-state hydroxyapatite and bone tissue through surface demineralization632645ENShichaoXieDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityMasahiroOkadaDivision of Biomaterials Science and Engineering, Graduate School of Dentistry, Tohoku UniversityHaruyukiAoyagiDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityAkihisaOtakaDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityXiaofengYangDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityTakayoshiNakanoDivision of Materials and Manufacturing Science, Graduate School of Engineering, The University of OsakaTakuyaMatsumotoDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityObjective: Current bone adhesives typically lack adequate mechanical strength, long-term stability, or biocompatibility. To address these limitations, we designed a new adhesion strategy using a solid-state hydroxyapatite (HAp) adhesive in combination with bone surface demineralization.<br>
Methods: Solid-state HAp adhesives were synthesized via wet chemical precipitation and heat treatment. Cortical bone specimens were partially demineralized with phosphoric acid (H3PO4) or ethylenediaminetetraacetic acid (EDTA), and characterized using scanning electron microscopy (SEM) and attenuated total reflectance–Fourier transform infrared spectroscopy (ATR-FTIR). Shear adhesion strength of HAp to demineralized bone was measured over time. In vivo fixation was assessed in rats using micro-computed tomography and histology. Statistical analysis used Tukey-Kramer tests after normality and variance checks.<br>
Results: Although the HAp adhesive failed to adhere to non-demineralized bone, effective adhesion was achieved on the surface-demineralized bone tissue. Shear adhesion strength was significantly higher in EDTA-treated samples (238.4 kPa at 10 h) compared to H3PO4-treated samples (102.9 kPa at 1 h), with performance correlating with demineralization depth. ATR-FTIR and SEM analyses revealed that EDTA preserved collagen's triple-helix structure and free water content, both enhancing adhesion. Animal experiments confirmed stable fixation of HAp adhesive to demineralized bone tissue.<br>
Conclusions: Surface demineralization enabled strong adhesion of the solid-state HAp adhesive to bone by exposing collagen swollen with water. Adhesion strength was influenced by structural changes in the demineralized layer, and the adhesive provided stable in vivo fixation, supporting its potential for bone-anchored biomedical applications.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X7962025Effects of Thoron Inhalation and Cyclosporin A Treatment on Dextran Sulfate Sodium-Induced Oxidative Damage in Mice421429ENAyumiTanakaGraduate School of Health Sciences, Okayama UniversityShotaNaoeGraduate School of Health Sciences, Okayama UniversityReijuTakenakaGraduate School of Health Sciences, Okayama UniversityNorieKanzakiNingyo-toge Environmental Engineering Center, Japan Atomic Energy AgencyAkihiroSakodaNingyo-toge Environmental Engineering Center, Japan Atomic Energy AgencyKiyonoriYamaokaFaculty of Health Sciences, Okayama UniversityTakahiroKataokaFaculty of Health Sciences, Okayama UniversityOriginal Article10.18926/AMO/69844Radon (222Rn; Rn) and thoron (220Rn; Tn) inhalation have been reported to enhance antioxidant activity in various organs. However, the effects of Tn on the colon have not been investigated. This study aimed to clarify the effects of Tn inhalation, alone and in combination with cyclosporin A (CsA), on dextran sulfate sodium (DSS)-induced colitis, and the accompanying oxidative stress, in mice. Male BALB/c mice were subjected to continuous 8-day Tn inhalation (c-Tn, 533±128 Bq/m3) or alternate-day Tn inhalation over the same period (f-Tn, 577±63Bq/m3), followed by treatment with 3% DSS and either CsA or vehicle for 7 days. Although the disease activity index (DAI) decreased significantly by day 2 in the c-Tn group, scores remained significantly higher than those in the f-Tn group. In the c-Tn group, superoxide dismutase and catalase activity in the colon were significantly elevated compared with those in sham controls. Thus, DSS-induced damage was effectively inhibited in the earlier stages by the c-Tn mode of inhalation than by the f-Tn mode. These findings suggest that continuous Tn inhalation more effectively attenuated early colitis symptoms than alternate-day inhalation, potentially through upregulation of antioxidant defenses. Tn and CsA showed no combined effects.No potential conflict of interest relevant to this article was reported.MDPI AGActa Medica Okayama2076-342515112025Sensory Modality-Dependent Interplay Between Updating and Inhibition Under Increased Working Memory Load: An ERP Study1178ENYuxiLuoGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityAoGuoDepartment of Psychology, Institute of Education, China West Normal UniversityJinglongWuFaculty of Biomedical Engineering, Shenzhen University of Advanced TechnologyJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityBackground/Objectives: Working memory (WM) performance relies on the coordination of updating and inhibition functions within the central executive system. However, their interaction under varying cognitive loads, particularly across sensory modalities, remains unclear. Methods: This study examined how sensory modality modulates flanker interference under increasing WM loads. Twenty-two participants performed a visual n-back task at three load levels (1-, 2-, and 3-back) while ignoring visual (within-modality) or auditory (cross-modality) flankers. Results: Behaviorally, increased WM load (2- and 3-back) led to reduced accuracy (AC) and prolonged reaction times (RTs) in both conditions. In addition, flanker interference was observed under the 2-back condition in both the visual within-modality (VM) and audiovisual cross-modality (AVM) tasks. However, performance impairment emerged at a lower load (2-back) in the VM condition, whereas in the AVM condition, it only emerged at the highest load (3-back). Significant performance impairment in the AVM condition occurred at higher WM loads, suggesting that greater WM load is required to trigger interference. Event-related potential (ERP) results showed that N200 amplitudes increased significantly for incongruent flankers under the highest WM load (3-back) in the visual within-modality condition, reflecting greater inhibitory demands. In the cross-modality condition, enhanced N200 was not observed across all loads and even reversed at low load (1-back). Moreover, the results also showed that P300 amplitude increased with load in the within-modality condition but decreased in the cross-modality condition. Conclusions: These results demonstrated that the interaction between updating and inhibition is shaped by both WM load and sensory modality, further supporting a sensory modality-specific resource allocation mechanism. The cross-modality configurations may enable more efficient distribution of cognitive resources under high load, reducing interference between concurrent executive demands.No potential conflict of interest relevant to this article was reported.Frontiers Media SAActa Medica Okayama1662-453X192025Effects of visual spatial frequency on audiovisual interaction: an event-related potential study1599114ENFengxiaWuSchool of Artificial Intelligence, Changchun University of Science and TechnologyYannaRenDepartment of Psychology, College of Humanities and Management, Guizhou University of Traditional Chinese MedicineTengfeiHaoSchool of Artificial Intelligence, Changchun University of Science and TechnologyJingjingYangSchool of Artificial Intelligence, Changchun University of Science and TechnologyQiongWuDepartment of Psychology, Suzhou University of Science and TechnologyJiajiaYangCognitive Neuroscience Laboratory, Graduate School of Natural Science and Technology, Okayama UniversityMengWangSchool of Artificial Intelligence, Changchun University of Science and TechnologySpatial frequency is a fundamental characteristic of visual signals that modulates the audiovisual integration behavior, but the neural mechanisms underlying spatial frequency are not well established. In the present study, the high temporal resolution of event-related potentials was used to investigate how visual spatial frequency modulates audiovisual integration. A visual orientation discrimination task was used, and the spatial frequency of visual stimuli was manipulated under three conditions. Results showed that the influence of visual spatial frequency on audiovisual integration is a dynamic process. The earliest audiovisual integration occurred over the left temporal-occipital regions in the early sensory stage (60–90 ms) for high spatial frequency conditions but was absent for low and middle spatial frequency conditions. In addition, audiovisual integration over fronto-central regions was delayed as spatial frequency increased (from 230–260 ms to 260–320 ms). The integration effect was also observed over parietal and occipital regions at 350–380 ms, and its strength gradually decreased at higher spatial frequencies. These discrepancies in the temporal and spatial distributions of audiovisual integration imply that the role of spatial frequency varies between early sensory and late cognitive stages. The findings of this study offer the first neural demonstration that spatial frequency modulates audiovisual integration, thus providing a basis for studying complex multisensory integration, especially in semantic and emotional domains.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama2772-5022522025Amelioration of Cd-induced bone deterioration by orally administered calcium phosphate101482ENPing-chinSungDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityAhmadBikharudinDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityMasahiroOkadaDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityRandaMusaDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityKentaUchidaDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityAkihisaOtakaDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityTadaakiMatsusakaDivision of Materials and Manufacturing Science, Graduate School of Engineering, Osaka UniversityAiraMatsugakiDivision of Materials and Manufacturing Science, Graduate School of Engineering, Osaka UniversityTakayoshiNakanoDivision of Materials and Manufacturing Science, Graduate School of Engineering, Osaka UniversityTakuyaMatsumotoDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityCadmium (Cd) is a heavy metal that accumulates in the body, primarily through daily grain intake, and has a high affinity for bone, leading to skeletal diseases such as osteomalacia and fractures. Hydroxyapatite (HAp), a major bone mineral component, is highly pH-sensitive and is known to incorporate Cd, as observed in studies of Itai-itai disease. Based on these findings, we hypothesized that HAp could serve as an effective oral detoxification material for heavy metals. This study investigated the efficacy of orally administered HAp in inhibiting Cd-induced changes in bone physical and chemical properties, comparing its effects to those of activated charcoal (AC), a common detoxifying agent. Six-week-old male ICR mice were exposed to cadmium via drinking water containing CdCl2 and subsequently given diets containing either HAp or AC for four weeks. Three-point bending tests, micro-CT analysis, and histological observations of the femurs demonstrated that mice receiving HAp exhibited improved mechanical strength and enhanced bone quality protection compared to the control and other Cd-treated groups. Activated charcoal also contributed to bone quality improvement at low concentrations, but its effect diminished at high concentrations. These results suggest that the oral administration of HAp may be a promising therapeutic strategy for suppressing cadmium-induced osteomalacia.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0264-12752602025An entangled material made from fiber aerosol deposition method115195ENHongwuYuFaculty of Environmental, Life, Natural Science and Technology, University of OkayamaNaoshiIkedaFaculty of Environmental, Life, Natural Science and Technology, University of OkayamaMasakazuMoriRyukoku UniversityJunKanoFaculty of Environmental, Life, Natural Science and Technology, University of OkayamaJae-HyukParkSchool of Advanced Materials Science & Engineering, Sungkyunkwan UniversityJunAkedoNational Institute of Advanced Industrial Science and TechnologyThis study demonstrates the successful application of Aerosol Deposition (AD) technology to short carbon fibers (length < 1 mm), enabling the rapid, three-dimensional (3D) fabrication of objects with vertical growth rates up to 0.3 mm/s, a significant improvement over conventional additive manufacturing. Through a series of experiments using this novel Fiber Aerosol Deposition (FAD) technology, three fiber lengths (47, 85, and 111 μm) and four substrate materials (carbon, polypropylene, polyethylene, and acrylonitrile butadiene styrene (ABS)) were investigated. Our findings indicate that both carbon substrate entanglement and fiber length critically influence deposition efficiency. Scanning electron microscopy (SEM) and X-ray computed tomography (CT) analyses reveal that during formation, longer fibers (>100 μm) initially create a cage-like framework, which is subsequently filled by shorter fibers. Density measurements and fiber distribution analysis confirmed that structures predominantly composed of shorter fibers exhibit higher packing densities, consistent with their role as filler material. These results collectively suggest that the FAD method’s formation mechanism relies on frictional entanglement rather than the room-temperature impact consolidation (RTIC) effect characteristic of traditional AD. This breakthrough presents a promising new technique for forming short fibers into functional 3D architectures, with potential applications extending to proteins, polymer fibers, and biomaterial fibers.No potential conflict of interest relevant to this article was reported.Biophysical Society of JapanActa Medica Okayama2189-47792232025Origin of the unique topology of the triangular water cluster in <i>Rubrobacter xylanophilus</i> rhodopsine220018ENTomoyasuNojiDepartment of Applied Chemistry, Graduate School of Engineering, The University of TokyoMasakiTsujimuraDepartment of Advanced Interdisciplinary Studies, The University of TokyoKeisukeSaitoDepartment of Applied Chemistry, Graduate School of Engineering, The University of TokyoKeiichiKojimaFaculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityYukiSudoFaculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityHiroshiIshikitaDepartment of Applied Chemistry, Graduate School of Engineering, The University of TokyoThe crystal structure of Rubrobacter xylanophilus rhodopsin (RxR) reveals a triangular cluster of three water molecules (W413, W415, and W419) at the extracellular proton-release site, near Glu187 and Glu197. Using a quantum mechanical/molecular mechanical approach, we identified the structural nature of this unique water cluster. The triangular shape is best reproduced when all three water molecules are neutral H2O with protonated Glu187 and deprotonated Glu197. Attempts to place H3O+ at any of these water molecules result in spontaneous proton transfer to one of the acidic residues and significant distortion from the crystal structure. The plane defined by the triangular water cluster extends into the guanidinium plane of Arg71, with both aligned along the W413...W419 axis. This extended plane lies nearly perpendicular to a five-membered, ring-like H-bond network involving two carboxyl oxygen atoms from Glu187 and one from Glu197. The resulting bipartite planar architecture, defined by the water triangle, Arg71, and the Glu187/Glu197 network may reflect the exceptional thermal stability in RxR.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama2041-17231612025Efficient and stable n-type sulfide overall water splitting with separated hydrogen production8786ENHaolinLuoResearch Center for Combustion and Environment Technology, Shanghai Jiao Tong UniversityZhixiLiuResearch Center for Combustion and Environment Technology, Shanghai Jiao Tong UniversityHaifengLvState Key Laboratory of Precision and Intelligent Chemistry, School of Chemistry and Material Sciences, and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), University of Science and Technology of ChinaJunie Jhon M.VequizoInstitute of Aqua Regeneration, Shinshu UniversityMengtingZhengCollege of Chemical and Biological Engineering, Zhejiang UniversityFengHanResearch Center for Combustion and Environment Technology, Shanghai Jiao Tong UniversityZhenYeResearch Center for Combustion and Environment Technology, Shanghai Jiao Tong UniversityAkiraYamakataFaculty of Natural Science and Technology, Okayama UniversityWenfengShangguanResearch Center for Combustion and Environment Technology, Shanghai Jiao Tong UniversityAdam F.LeeCentre for Catalysis and Clean Energy, School of Environment and Science, Griffith UniversityXiaojunWuState Key Laboratory of Precision and Intelligent Chemistry, School of Chemistry and Material Sciences, and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), University of Science and Technology of ChinaDomenKazunariInstitute of Aqua Regeneration, Shinshu UniversityJunLuCollege of Chemical and Biological Engineering, Zhejiang UniversityZhiJiangResearch Center for Combustion and Environment Technology, Shanghai Jiao Tong UniversityN-type sulfide semiconductors are promising photocatalysts due to their broad visible-light absorption, facile synthesis and chemical diversity. However, photocorrosion and limited electron transport in one-step excitation and solid-state Z-scheme systems hinder efficient overall water splitting. Liquid-phase Z-schemes offer a viable alternative, but sluggish mediator kinetics and interfacial side reactions impede their construction. Here we report a stable Z-scheme system integrating n-type CdS and BiVO₄ with a [Fe(CN)₆]³⁻/[Fe(CN)₆]⁴⁻ mediator, achieving 10.2% apparent quantum yield at 450 nm with stoichiometric H₂/O₂ evolution. High activity reflects synergies between Pt@CrOx and Co3O4 cocatalysts on CdS, and cobalt-directed facet asymmetry in BiVO₄, resulting in matched kinetics for hydrogen and oxygen evolution in a reversible mediator solution. Stability is dramatically improved through coating CdS and BiVO4 with different oxides to inhibit Fe4[Fe(CN)6]3 precipitation and deactivation by a hitherto unrecognized mechanism. Separate hydrogen and oxygen production is also demonstrated in a two-compartment reactor under visible light and ambient conditions. This work unlocks the long-sought potential of n-type sulfides for efficient, durable and safe solar-driven hydrogen production.No potential conflict of interest relevant to this article was reported.WileyActa Medica Okayama1616-301X2025A Biologically-Architected Wear and Damage-Resistant Nanoparticle Coating From the Radular Teeth of Cryptochiton stellerie21664ENTaifengWangDepartment of Materials Science and Engineering, University of CaliforniaYuChenLyles School of Civil and Construction Engineering, Purdue UniversityEzraSarmientoDepartment of Materials Science and Engineering, University of CaliforniaTaigeHaoMaterials and Manufacturing Technologies Program, University of CaliforniaAtsushiArakakiDivision of Biotechnology and Life Science, Institute of Engineering, Tokyo University of Agriculture and Technology MichikoNemotoGraduate School of Environmental and Life Science, Okayama UniversityPabloZavattieriLyles School of Civil and Construction Engineering, Purdue UniversityDavidKisailusDepartment of Materials Science and Engineering, University of CaliforniaNature utilizes simple building blocks to construct mechanically robust materials that demonstrate superior performance under extreme conditions. These exquisite structures result from the controlled synthesis and hierarchical assembly of nanoscale organic and mineral components that have provided critical evolutionary advantages to ensure survival. One such example is the ultrahard radular teeth found in mollusks, which are used to scrape against rock to feed on algae. Here, it is reported that the leading edges of these teeth consist of a wear-resistant coating that is comprised of densely packed ≈65 nm magnetic nanoparticles integrated within an organic matrix of chitin and protein. These mesocrystalline magnetite-based structures are assembled from smaller, highly aligned nanocrystals with inter/intracrystalline organics introduced during the crystallization process. Nanomechanical testing reveals that this multi-scale, nano-architected coating has a combination of increased hardness and a slight decrease in modulus versus geologic magnetite provides the surface of the chiton tooth with superior abrasion resistance. The mesocrystalline structures fracture at primary domain interfaces, corroborated by computational models, providing significant toughening to the tooth under extreme contact stresses. The design features revealed provide insight for the design and fabrication of next-generation advanced wear- and impact-resistant coatings for tooling, machinery, wind turbines, armor, etc.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0301-679X2142026The influence of lubricant additives and surface roughness and hardness of material on the damage behavior of gears111341ENTakuyaOhnoFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityTadashiShiotaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityMasahiroFujiiFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityThis study investigates the influence of lubricant additives, surface roughness, and material hardness on gear damage behavior under boundary lubrication conditions. We conducted both the Short-term Test and the Standard Test using an FZG gear test machine to evaluate how lubricant additives and gear surface roughness influence damage progression when the surface roughness exceeds the oil-film thickness. Acid phosphate ester effectively suppressed micropitting through surface smoothing but led to severe damage such as pitting and scuffing during prolonged use. In contrast, sulfurized fatty oil promoted mild wear, delaying catastrophic failures and extending gear life. Higher surface roughness accelerated wear, while increased hardness reduced deformation but it expanded damage areas. The study found that initial surface roughness and its progress during load stages strongly correlate with gear durability. Measurement of arithmetic mean roughness after sufficient running-in under actual load conditions proved useful for predicting long-term performance. These findings highlight the importance of selecting lubricant formulations tailored to specific gear operating environments and damage modes. Understanding the interplay between lubrication chemistry and material properties enables the design of more durable gear systems.No potential conflict of interest relevant to this article was reported.Japanese Society of TribologistsActa Medica Okayama1881-21982032025Water Lubrication of Polysiloxane-Containing Polyimide Coatings on Stainless Steel Substrates124129ENYuelinFanGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityTadashiShiotaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityYuyaOmiyaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityMasahiroFujiiFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityThis study investigated the water-lubricated tribological properties of coatings made of a novel polysiloxane-containing polyimide (si-PI) material that was recently developed for the aerospace industry and can be diluted with the harmless and environmentally friendly ethanol or water. The si-PI coatings were deposited on stainless steel (JIS SUS304) substrates at curing temperatures ranging from 160°C to 275°C. Their water lubrication properties were measured by rubbing the coatings against each other in water at room temperature. The coatings exhibited lower friction than conventional polyimide materials, with a minimum friction coefficient of 0.04, which was lower than that of polytetrafluoroethylene (PTFE) measured under the same sliding conditions. Unlike the conventional polyimide, the coatings did not exhibit any obvious wear or damage. The results demonstrate that the si-PI coating is a promising low-friction and highly durable coating for water lubrication.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0266-352X1782025End-to-end time-dependent probabilistic assessment of landslide hazards using hybrid deep learning simulator106920ENMengluHuangDepartment of Civil and Environmental Engineering, Okayama UniversityShin-ichiNishimuraDepartment of Civil and Environmental Engineering, Okayama UniversityToshifumiShibataDepartment of Civil and Environmental Engineering, Okayama UniversityZe ZhouWangMarie Skłodowska-Curie Fellow, Department of Engineering, University of CambridgeEarly warning detection of landslide hazards often requires real-time or near real-time predictions, which can be challenging due to the presence of multiple geo-uncertainties and time-variant external environmental loadings. The propagation of these uncertainties at the system level for understanding the spatiotemporal behavior of slopes often requires time-consuming numerical calculations, significantly hindering the establishment of an early warning system. This paper presents a hybrid deep learning simulator, which fuses parallel convolutional neural networks (CNNs) and long short-term memory (LSTM) networks through attention mechanisms, termed PCLA-Net, to facilitate time-dependent probabilistic assessment of landslide hazards. PCLA-Net features two novelties. First, it is capable of simultaneously handling both temporal and spatial information. CNNs specialize in interpreting spatial data, while LSTM excels in handling time-variant data. Coupled with two attention mechanisms, the two modules are combined to probabilistically predict the spatiotemporal behavior of slopes. Second, PCLA-Net realizes end-to-end predictions. In this paper, the Liangshuijing landslide in the Three Gorges Reservoir area of China is used to illustrate PCLA-Net. It is first validated followed by a comparison with existing techniques to demonstrate its improved predictive capabilities. The proposed PCLA-Net simulator can achieve the same level of accuracy with at least 50% reduction in computation resources.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama1939-59812025Effect of Repeated Gravity Casting on the Microstructure and Mechanical Properties of 6061 Aluminum AlloyENMitsuhiroOkayasuDepartment of Mechanical Systems and Engineering, Okayama UniversityShoueiMakinoDepartment of Mechanical Systems and Engineering, Okayama UniversityShotaNakagawaResearch & Development Center, Marketing & Technology Division, UACJ CorporationShuheiTakeuchiDepartment of Mechanical Systems and Engineering, Okayama UniversityYoshifumiShinzatoResearch & Development Center, Marketing & Technology Division, UACJ CorporationTadashiMinodaResearch & Development Center, Marketing & Technology Division, UACJ CorporationNaotakaOhtsukaResearch & Development Center, Marketing & Technology Division, UACJ CorporationThis study systematically investigates the effects of repeated gravity casting on the microstructure and mechanical properties of 6061 aluminum alloy. With an increasing number of casting cycles from one to ten, grain coarsening and a decrease in dislocation density were observed, mainly due to the significant depletion of magnesium from 1.03 to 0.01% and titanium from 0.009 to 0.005%. These microstructural changes led to a decrease in solid-solution strengthening and grain-boundary strengthening, resulting in a 30% reduction in tensile strength, while ductility increased by about three times. Moreover, work hardening decreased with increasing the casting cycle, which can be attributed not only to the microstructural changes but also to the increase in stacking fault energy (SFE) associated with compositional evolution. From the transmission electron microscopy (TEM) observations, in the 1-cycle sample, Mg2Si precipitates were finely dispersed and a high amount of Mg element in the matrix, resulting in significant dislocation accumulation, whereas the 10-cycle sample exhibited weaker dislocation tangling. These microstructural evolutions provide insight into the degradation of mechanical performance in aluminum alloys subjected to multiple casting processes.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama2510-15606232025Enhanced electric power generation in PZT ceramics via stress control10371043ENMitsuhiroOkayasuDepartment of Mechanical Systems and Engineering, Okayama UniversityItsukiShimazuDepartment of Mechanical Systems and Engineering, Okayama UniversityThis study aimed to enhance the electric power generation of lead zirconate titanate piezoelectric (PZT) ceramics by optimizing stress distribution. Specifically, it focused on applying high stress over a broad area of the PZT ceramic to induce shape deformation in the PZT plate. Pre-straining the PZT plate into an arch shape improved voltage generation, reaching its peak at a maximum deflection of 0.04 mm due to the expanded and intensified stress distribution. However, exceeding this deflection threshold led to a decline in voltage output due to material degradation, including crack formation and 90° domain switching. Finite element analysis confirmed that the increased stress distribution in the pre-strained PZT plate contributed to higher voltage output. Additionally, electron backscatter diffraction analysis revealed that at higher pre-strains (deflection of 0.08 mm), 90°domain switching occurred, resulting in increased internal strain and potential crack formation. Experimental investigations using bulk PZT rods further demonstrated that moderate pre-straining effectively enhanced voltage output.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama1939-59812042025Upgrading Recycle Technology for Iron Removal in ADC12 Alloy Using Gravity and Magnetic Force23542361ENM.OkayasuDepartment of Mechanical Systems and Engineering, Okayama UniversityS.TakeuchiDepartment of Mechanical Systems and Engineering, Okayama UniversityM.SyahidDepartment of Mechanical Engineering, Hasanuddin UniversityT.IkedaDepartment of Mechanical Systems and Engineering, Okayama UniversityAs there is a technical issue to remove iron elements during aluminum recycling process, an attempt was made to evaluate the effectiveness of magnetic and gravitational separation methods for removing iron from Al-Si-Cu alloy (ADC12). A rare-earth samarium–cobalt (SmCo) magnet was employed during the solidification process to attract Fe-rich eutectic structures. The microstructural analysis revealed that block-like Fe-Cr-Si-based phases formed preferentially near the magnet and at the bottom of the crucible, suggesting that magnetic and gravity attraction contributed to the localized segregation of these phases. However, other Fe-based phases, including Fe-Si-based ones, are not strongly affected by magnet. Additionally, prolonged heating in the solid–liquid coexistence (SLC) region at 577 °C for 10 h led to the settling of a largely grown Fe-Cr-Si-rich crystal at the bottom of the crucible due to gravity. Other structures, such as Si-rich eutectic phases, were not influenced by gravity, which may be caused by the low density of Si compared to Fe one. From this approach, combining magnetic attraction and gravitational settling is a promising method to promote the removal of iron impurities from aluminum alloys.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama0361-52355472025Electric Power Generation of PZT Piezoelectric Ceramics Using Both Direct and Inverse Piezoelectric Effects51435150ENMitsuhiroOkayasuDepartment of Mechanical Systems and Engineering, Okayama UniversityItsukiShimazuDepartment of Mechanical Systems and Engineering, Okayama UniversityThe power generation characteristics of lead zirconate titanate (PZT) piezoelectric ceramics (E-PZT) were experimentally investigated using a specialized PZT system which utilizes both the direct and inverse piezoelectric effects inherent to PZT materials. Specifically, electric voltage was generated from the vibration of E-PZT through the inverse piezoelectric effect, induced by mechanical energy transferred from the vibration of a PZT piezoelectric ceramic plate, such as a buzzer (B-PZT). In this system, an insulating material was placed between the B-PZT and E-PZT plates to address the electrical conductivity of the PZT ceramic. Various insulating materials with different thicknesses and different hardness were prepared. Additionally, the PZT systems were mounted in several distinct configurations to evaluate their power generation performance: a fully fixed around the PZT plate and a free-hanging setup. The influence of insulation materials and mounting conditions on electrical output was analyzed at various loading conditions, e.g., loading value and frequency. The results demonstrated that the generated electric voltage decreased with increasing insulation thickness and hardness, suggesting that thinner and softer insulating materials enhance output voltage. Conversely, when the PZT system was securely fixed around the PZT plate with an appropriate fixture, a higher and more stable electric voltage was generated. The voltage generated also varied by the loading condition, which is related to the strain value of the E-PZT plate, demonstrating a linear relationship between the strain and the output voltage. Notably, the strain was significantly influenced by resonant frequencies, which played a crucial role in achieving higher voltage outputs. Based on these experimental results, two power generation systems have been proposed.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0921-883136102025Evaluating the effects of electrolytes on the interaction forces between alumina surfaces in polyacrylic acid solutions using atomic force microscopy105028ENNaotoKishimotoGraduate School of Natural Science and Technology, Okayama UniversityRyotaKajiFaculty of Science and Engineering, Doshisha UniversityKatsumiTsuchiyaFaculty of Science and Engineering, Doshisha UniversityKoreyoshiImamuraGraduate School of Natural Science and Technology, Okayama UniversityNaoyukiIshidaFaculty of Science and Engineering, Doshisha UniversityEvaluation and control of ceramic slurry at the microscopic level are critical to ensure consistent quality in manufactured ceramics. Notably, metal ions such as Mg2+ and Al3+ are common in ceramic slurries and significantly influence the stability of particle. This study applied atomic force microscopy to investigate the interaction forces between alumina particle surfaces in the presence of different concentrations of three metal ions and polyacrylic acid (PAA), a widely used dispersant.<br>
The attractive forces observed at low PAA concentrations were attributed to polymer bridging between alumina surfaces, whereas the repulsive forces observed at high PAA concentrations were attributed to the domination of steric repulsion between adsorbed PAA molecules. The presence of multivalent metal ions, such as Mg2+ and Al3+, modulated these interactions; an increasing ion valence induced a transition from repulsive to attractive force, primarily owing to electrostatic screening, which caused conformational collapse of the PAA chains and diminished the range of steric repulsion. Similarly, increasing the concentration of these metal ions decreased the range of repulsive forces, eventually resulting in a net attraction driven by the same electrostatic and polymer conformation mechanisms. Notably, the addition of 0.1 M AlCl3 produced an anomalous long-range attraction between surfaces that could not be explained by conventional mechanisms, such as polymer bridging or electrostatic interactions between charge domains.No potential conflict of interest relevant to this article was reported.WileyActa Medica Okayama0960-741212352025RNA processing/modifying enzymes play key roles in the response to thermospermine in Arabidopsis thalianae70476ENMitsuruSaraumiGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityTakahiroTanakaGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityDaikiKoyamaGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityYoshitakaNishiGraduate School of Engineering, Kyushu Sangyo UniversityYoshihiroTakahashiDepartment of Life Science, Faculty of Life Science, Kyushu Sangyo UniversityHiroyasuMotoseGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityTakuTakahashiGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityThermospermine is involved in negative regulation of xylem differentiation by enhancing the translation of mRNAs of the SAC51 gene family in Arabidopsis (Arabidopsis thaliana). These mRNAs contain conserved upstream open reading frames (uORFs) that interfere with the translation of the main ORF. To investigate the mechanism by which thermospermine acts in this process, we isolated mutants insensitive to thermospermine, named ‘its’. We show that the four genes responsible for these mutants, its1 to its4, encode: (i) a homolog of SPOUT RNA methyltransferase, (ii) an rRNA pseudouridine synthase CBF5/NAP57, (iii) a putative spliceosome disassembly factor STIPL1/NTR1, and (iv) a plant-specific RNA-binding protein PHIP1. These four mutants were found to have much higher levels of thermospermine than the wild-type. While all these mutants except its1 appear almost normal, they enhance the dwarf phenotype of a mutant of ACL5, which encodes thermospermine synthase, resulting in tiny plants resembling a double knockout of ACL5 and SACL3, a member of the SAC51 family. Reporter assays revealed that GUS activity from the CaMV 35S promoter-SAC51 5′-GUS fusion construct was significantly reduced in its1 and its4 or not affected in its2 and its3, while it was slightly increased in its1, its3, and its4, or not changed in its2 by thermospermine. These findings underscore the critical role of RNA processing and modification in the thermospermine-dependent translational regulation of uORF-containing transcripts.No potential conflict of interest relevant to this article was reported.Cambridge University Press (CUP)Acta Medica Okayama0022-112010192025Experimental and numerical study on the inertial migration of hydrogel particles suspended in square channel flowsA22ENYumaHirohataGraduate School of Engineering Science, The University of OsakaKazusaSaiDepartment of Pure and Applied Physics, Kansai UniversityYukiTangeDepartment of Pure and Applied Physics, Kansai UniversityTomohiroNishiyamaDepartment of Pure and Applied Physics, Kansai UniversityHarukaMinatoGraduate School of Environmental Life Natural Science and Technology, Okayama UniversityDaisukeSuzukiGraduate School of Environmental Life Natural Science and Technology, Okayama UniversityTomoakiItanoDepartment of Pure and Applied Physics, Kansai UniversityKazuyasuSugiyamaGraduate School of Engineering Science, The University of OsakaMasakoSugihara-SekiDepartment of Pure and Applied Physics, Kansai UniversityThe inertial migration of hydrogel particles suspended in a Newtonian fluid flowing through a square channel is studied both experimentally and numerically. Experimental results demonstrate significant differences in the focusing positions of the deformable and rigid particles, highlighting the role of particle deformability in inertial migration. At low Reynolds numbers (Re), hydrogel particles migrate towards the centre of the channel cross-section, whereas the rigid spheres exhibit negligible lateral motion. At finite Re, they focus at four points along the diagonals in the downstream cross-section, in contrast to the rigid particles which focus near the centre of the channel face at similar Re . Numerical simulations using viscous hyperelastic particles as a model for hydrogel particles reproduced the experimental results for the particle distribution with an appropriate Young’s modulus of the hyperelastic particles. Further numerical simulations over a broader range of Re and the capillary number (Ca) reveal various focusing patterns of the particles in the channel cross-section. The phase transitions between them are discussed in terms of the inertial lift and the lift due to particle deformation, which would act in the direction towards lower shear. The stability of the channel centre is analysed using an asymptotic expansion approach to the migration force at low Re and Ca. The theoretical analysis predicts the critical condition for the transition, which is consistent with the direct numerical simulation. These experimental, numerical and theoretical results contribute to a deeper understanding of inertial migration of deformable particles.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0008-62232432025Organic solvent transport through reduced graphene oxide membranes with controlled oxygen content120539ENHongzheChenSchool of Materials Science and Engineering, University of New South Wales SydneyTongxiLinSchool of Materials Science and Engineering, University of New South Wales SydneyZeno RizqiRamadhanElectron Microscope Unit, University of New South WalesAdityaRawalMark Wainwright Analytical Centre, University of New South WalesYutaNishinaResearch Institute for Interdisciplinary Science, Okayama UniversityAmirKartonSchool of Science and Technology, University of New EnglandXiaojunRenSchool of Materials Science and Engineering, University of New South Wales SydneyRakeshJoshiSchool of Materials Science and Engineering, University of New South Wales SydneyRecent advances in membranes based on 2-dimensional (2D) materials have enabled precise control over angstrom-scale pores, providing a unique platform for studying diverse mass transport mechanisms. In this work, we systematically investigate the transport of solvent vapors through 2D channels made of graphene oxide (GO) laminates with precisely controlled oxygen content. Using in-situ chemical reduction of GO with vitamin C, we fabricated reduced GO membranes (VRGMs) with oxygen content systematically decreased from 31.6 % (pristine GO) to 24.0 % (VRGM-maximum reduction). Vapor permeability measurements showed a distinct correlation between oxygen functional groups and solvent transport behaviour. Specifically, non-polar hexane exhibits 114 % of enhanced permeance through the reduced membranes with larger graphitic domains, while the permeance of water decreases by 55 %. With the support of density functional theory (DFT) simulations, we modelled the hydrogen-bond and dispersion complexes between the solvents and GO and calculated the complexation energies. The simulation results suggest that polar molecules interact with the oxygen functional groups of GO via a hydrogen-bond network, supporting in-plane transport. In contrast, van der Waals forces drive the transport of low-polarity solvents along the graphitic domains of the 2D channel in reduced GO membranes. Our findings provide potential strategies for future design of organic solvent nanofiltration membranes.No potential conflict of interest relevant to this article was reported.MDPI AGActa Medica Okayama1660-33972352025Novel Anti-MRSA Peptide from Mangrove-Derived Virgibacillus chiguensis FN33 Supported by Genomics and Molecular Dynamics209ENNamfaSermkaewSchool of Pharmacy, Walailak UniversityApichartAtipairinSchool of Pharmacy, Walailak UniversityPhetcharatBoonruamkaewSchool of Pharmacy, Walailak UniversitySucheewinKrobthongCenter of Excellence in Natural Products Chemistry (CENP), Department of Chemistry, Faculty of Science, Chulalongkorn UniversityChanatAonbangkhenCenter of Excellence in Natural Products Chemistry (CENP), Department of Chemistry, Faculty of Science, Chulalongkorn UniversityJumpeiUchiyamaDepartment of Bacteriology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityYodyingYingchutrakulNational Center for Genetic Engineering and Biotechnology, National Science and Technology Development AgencyNuttaponSongnakaSchool of Pharmacy, Walailak UniversityAntimicrobial resistance (AMR) is a global health threat, with methicillin-resistant Staphylococcus aureus (MRSA) being one of the major resistant pathogens. This study reports the isolation of a novel mangrove-derived bacterium, Virgibacillus chiguensis FN33, as identified through genome analysis and the discovery of a new anionic antimicrobial peptide (AMP) exhibiting anti-MRSA activity. The AMP was composed of 23 amino acids, which were elucidated as NH3-Glu-Gly-Gly-Cys-Gly-Val-Asp-Thr-Trp-Gly-Cys-Leu-Thr-Pro-Cys-His-Cys-Asp-Leu-Phe-Cys-Thr-Thr-COOH. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for MRSA were 8 µg/mL and 16 µg/mL, respectively. FN33 AMP induced cell membrane permeabilization, suggesting a membrane-disrupting mechanism. The AMP remained stable at 30–40 °C but lost activity at higher temperatures and following exposure to proteases, surfactants, and extreme pH. All-atom molecular dynamics simulations showed that the AMP adopts a β-sheet structure upon membrane interaction. These findings suggest that Virgibacillus chiguensis FN33 is a promising source of novel antibacterial agents against MRSA, supporting alternative strategies for drug-resistant infections.No potential conflict of interest relevant to this article was reported.MDPI AGActa Medica Okayama1422-006726172025Augmentation of the Benzyl Isothiocyanate-Induced Antiproliferation by NBDHEX in the HCT-116 Human Colorectal Cancer Cell Line8145ENRuitongSunGraduate School of Environmental and Life Science, Okayama UniversityAinaYanoGraduate School of Environmental and Life Science, Okayama UniversityAyanoSatohGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityShintaroMunemasaGraduate School of Environmental and Life Science, Okayama UniversityYoshiyukiMurataGraduate School of Environmental and Life Science, Okayama UniversityToshiyukiNakamuraGraduate School of Environmental and Life Science, Okayama UniversityYoshimasaNakamuraGraduate School of Environmental and Life Science, Okayama UniversityIncreased drug metabolism and elimination are prominent mechanisms mediating multidrug resistance (MDR) to not only chemotherapy drugs but also anti-cancer natural products, such as benzyl isothiocyanate (BITC). To evaluate the possibility of combined utilization of a certain compound to overcome this resistance, we focused on glutathione S-transferase (GST)-dependent metabolism of BITC. The pharmacological treatment of a pi-class GST-selective inhibitor, 6-(7-nitro-2,1,3-benzoxadiazol-4-ylthio)hexanol (NBDHEX), significantly increased BITC-induced toxicity in human colorectal cancer HCT-116 cells. However, NBDHEX unexpectedly increased the level of the BITC–glutathione (GSH) conjugate as well as BITC-modified proteins, suggesting that NBDHEX might increase BITC-modified protein accumulation by inhibiting BITC–GSH excretion instead of inhibiting GST. Furthermore, NBDHEX significantly potentiated BITC-induced apoptosis with the enhanced activation of apoptosis-related pathways, such as c-Jun N-terminal kinase and caspase-3 pathways. These results suggested that combination treatment with NBDHEX may be an effective way to overcome MDR with drug efflux and thus induce the biological activity of BITC at lower doses.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama1939-59812025MATERIAL PROPERTIES OF DIE-CASTING DIE AROUND HEAT-CHECKING CREATED BY A HIGH-PRESSURE ALUMINUM ALLOY DIE-CASTING OPERATIONENMitsuhiroOkayasuDepartment of Mechanical Systems Engineering, Okayama UniversityJunyaShimazuDepartment of Mechanical Systems Engineering, Okayama UniversityIn this study, the material properties of a nitride die-casting die exhibiting heat-checking after the die-casting process were experimentally investigated using various methods. Based on the obtained results, the authors believe that several possible mechanisms underlying the formation of heat-checking can be identified. The microstructure of the die-casting die near the heat-checking region is characterized by equiaxed grains along the vicinity of the prior γ-grain boundaries, resulting from the lath martensitic formation. Additionally, numerous Cr–Mo–V-based nitride particles, approximately 100 nm in diameter, are precipitated. The surface hardness of the die-casting die, enhanced by nitriding, induces compressive residual stresses and increases adhesive forces. As a result of changes in microstructural characteristics and crack formation, the stress state near the die-casting die is altered, where compressive residual stresses, observed in the die-casting die, are released, leading to the tensile residual stresses. This phenomenon could accelerate the formation of a large number of heat-checking cracks.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2227-70801342025An Implementation of Creep Test Assisting System with Dial Gauge Needle Reading and Smart Lighting Function for Laboratory Automation139ENDezhengKong Graduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityNobuoFunabiki Graduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityShihaoFang Graduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityNoprianto Graduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityMitsuhiroOkayasu Graduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityPradiniPuspitaningayu Department of Electrical Engineering, Universitas Negeri SurabayaFor decades, analog dial gauges have been essential for measuring and monitoring data at various industrial instruments including production machines and laboratory equipment. Among them, we focus on the instrument for creep test in a mechanical engineering laboratory, which evaluates material strength under sustained stress. Manual reading of gauges imposes significant labor demands, especially in long-duration tests. This burden further increases under low-lighting environments, where poor visibility can lead to misreading data points, potentially compromising the accuracy of test results. In this paper, to address the challenges, we implement a creep test assisting system that possesses the following features: (1) to save the installation cost, a web camera and Raspberry Pi are employed to capture images of the dial gauge and automate the needle reading by image processing in real time, (2) to ensure reliability under low-lighting environments, a smart lighting mechanism is integrated to turn on a supplementary light when the dial gauge is not clearly visible, and (3) to allow a user to stay in a distant place from the instrument during a creep test, material break is detected and the corresponding message is notified to a laboratory staff using LINE automatically. For evaluations, we install the implemented system into a material strength measuring instrument at Okayama University, Japan, and confirm the effectiveness and accuracy through conducting experiments under various lighting conditions.No potential conflict of interest relevant to this article was reported.IOP PublishingActa Medica Okayama1742-658828922024Crystal Grain Rotation during Tensile Test of Polycrystalline Pure Titanium Thin Sheet Based on Surface Height and Crystal Orientation012002ENNaoyaTadaOkayama UniversityHiroakiOhashiOkayama UniversityTakeshiUemoriOkayama UniversityJunjiSakamotoOkayama UniversityThin sheets and wires of polycrystalline pure titanium are important materials for various devices used in electrical, mechanical, dental, and medical fields. Since pure titanium shows strong anisotropy in elastic and plastic deformation, and the individual grains comprising a polycrystalline body have different orientations and geometries, inhomogeneous deformation always occurs on the microscopic scale. This inhomogeneity is more significant in thin films than in bulk materials. It is therefore important to investigate the inhomogeneous deformation of pure titanium thin sheets to ensure the reliability of various titanium devices. In this study, thin-sheet specimens made of polycrystalline pure titanium were subjected to tensile testing. Inhomogeneous deformation was evaluated on the basis of two kinds of crystal grain rotations based on surface height and crystal orientation. The results under elastic and plastic tensile conditions were compared.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0360-31991402025Advances in filler-crosslinked membranes for hydrogen fuel cells in sustainable energy generation745776ENAminulIslamDepartment of Petroleum and Mining Engineering, Jashore University of Science and TechnologyMamunShahriarDepartment of Petroleum and Mining Engineering, Jashore University of Science and TechnologyMd. TarekulIslamDepartment of Leather Engineering, Faculty of Mechanical Engineering, Khulna University of Engineering and TechnologySiow HwaTeoIndustrial Chemistry Program, Faculty of Science and Natural Resources, Universiti Malaysia SabahM. Azizur R.KhanDepartment of Chemistry, Jashore University of Science and TechnologyYun HinTaufiq-YapCatalysis Science and Technology Research Centre, Faculty of Science, Universiti Putra MalaysiaSuman C.MohantaDepartment of Chemistry, Jashore University of Science and TechnologyAriyan IslamRehanDepartment of Chemistry, School of Science, The University of TokyoAdiba IslamRaseeDepartment of Chemistry, Graduate School of Science, Osaka UniversityKhadiza TulKubraDepartment of Chemistry, Graduate School of Science, Osaka UniversityMd. MunjurHasanDepartment of Chemistry, Graduate School of Science, Osaka UniversityMd. ShadSalmanInstitute for Chemical Research, Kyoto UniversityR.M.WaliullahInstitute for Chemical Research, Kyoto UniversityMd. NazmulHasanDepartment of Chemistry, School of Science, The University of TokyoMd. ChanmiyaSheikhDivision of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama UniversityTetsuyaUchidaDivision of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama UniversityMrs EtiAwualInstitute for Chemical Research, Kyoto UniversityMohammed SohrabHossainDepartment of Chemistry, Graduate School of Science, Osaka UniversityHusseinZnadWestern Australian School of Mines: Minerals, Energy and Chemical Engineering, Curtin UniversityMd. RabiulAwualWestern Australian School of Mines: Minerals, Energy and Chemical Engineering, Curtin UniversityFuel cell membranes can be used in various ways to achieve zero-emission transport and energy systems, which offer a promising way to power production due to their higher efficiency compared to the internal combustion engine and the eco-environment. Perfluoro sulfonic acid membranes used for proton exchange membranes (PEMs) have certain drawbacks, like higher fuel permeability and expense, lower mechanical and chemical durability, and proton conductivity under low humidity and above 80 °C temperature. Researchers have drawn their attention to the production of polymer electrolyte membranes with higher proton conductivity, thermal and chemical resilience, maximum power density, lower fuel permeability, and lower expense. For sustainable clean energy generation, a review covering the most useful features of advanced material-associated membranes would be of great benefit to all interested communities. This paper endeavors to explore several types of novel inorganic fillers and crosslinking agents, which have been incorporated into membrane matrices to design the desired properties for an advanced fuel cell system. Membrane parameters such as proton conductivity, the ability of H2 transport, and the stability of the membrane are described. Research directions for developing fuel cell membranes are addressed based on several challenges suggested. The technological advancement of nanostructured materials for fuel cell applications is believed to significantly promote the future clean energy generation technology in practice.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0360-31991012025Next frontier in photocatalytic hydrogen production through CdS heterojunctions173211ENAminulIslamDepartment of Petroleum and Mining Engineering, Jashore University of Science and TechnologyAbdulMalekDepartment of Petroleum and Mining Engineering, Jashore University of Science and TechnologyMd. TarekulIslamDepartment of Leather Engineering, Faculty of Mechanical Engineering, Khulna University of Engineering and TechnologyFarzana YeasminNipaDepartment of Petroleum and Mining Engineering, Jashore University of Science and TechnologyObayedRaihanDepartment of Pharmaceutical Sciences, College of Health Sciences and Pharmacy, Chicago State UniversityHasanMahmudBangladesh Energy and Power Research Council (BEPRC)Md. EliasUddinDepartment of Leather Engineering, Faculty of Mechanical Engineering, Khulna University of Engineering and TechnologyMohd LokmanIbrahimSchool of Chemistry and Environment, Faculty of Applied Sciences, Universiti Teknologi MARAG.Abdulkareem-AlsultanCatalysis Science and Technology Research Centre, Faculty of Science, Universiti Putra MalaysiaAlam HossainMondalUSAID - Bangladesh Advancing Development and Growth through Energy (BADGE) Project, Tetra TechMd. MunjurHasanDepartment of Chemistry, Graduate School of Science, Osaka UniversityMd. ShadSalmanInstitute for Chemical Research, Kyoto UniversityKhadiza TulKubraDepartment of Chemistry, Graduate School of Science, Osaka UniversityMd. NazmulHasanDepartment of Chemistry, School of Science, The University of TokyoMd. ChanmiyaSheikhDivision of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama UniversityTetsuyaUchidaDivision of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama UniversityAdiba IslamRaseeDepartment of Chemistry, Graduate School of Science, Osaka UniversityAriyan IslamRehanDepartment of Chemistry, School of Science, The University of TokyoMrs EtiAwualInstitute for Chemical Research, Kyoto UniversityMohammed SohrabHossainDepartment of Chemistry, Graduate School of Science, Osaka UniversityR.M.WaliullahInstitute for Chemical Research, Kyoto UniversityMd. RabiulAwualWestern Australian School of Mines: Minerals, Energy and Chemical Engineering, Curtin UniversityPhotocatalytic hydrogen (H₂) generation via solar-powered water splitting represents a sustainable solution to the global energy crisis. Cadmium sulfide (CdS) has emerged as a promising semiconductor photocatalyst due to its tunable bandgap, high physicochemical stability, cost-effectiveness, and widespread availability. This review systematically examines recent advancements in CdS-based heterojunctions, categorized into CdS-metal (Schottky), CdS-semiconductor (p-n, Z-scheme, S-scheme), and CdS-carbon heterojunctions. Various strategies employed to enhance photocatalytic efficiency and stability are discussed, including band structure engineering, surface modification, and the incorporation of crosslinked architectures. A critical evaluation of the underlying photocatalytic mechanisms highlights recent efforts to improve charge separation and photostability under operational conditions. This review highlights the challenges and opportunities in advancing CdS-based photocatalysts and provides a direction for future research. The insights presented aim to accelerate the development of efficient and durable CdS-based photocatalysts for sustainable H₂ production.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0924-42473902025Extension-type flexible pneumatic actuator with a large extension force using a cross-link mechanism based on pantographs116594ENSoShimookaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityKazumaTadachiMechanical and Systems Engineering Program, School of Engineering, Okayama UniversityTetsushiKamegawaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityIn this study, we propose an extension-type flexible pneumatic actuator (EFPA) with a high extension force and no buckling. In a previous study, soft actuators that extended in the axial direction by applying a supply pressure were unable to generate the extension’s pushing force because the actuators buckled owing to their high flexibility. To generate a pushing force, the circumferential stiffness of an extension-type flexible soft actuator must be reinforced. Therefore, a cross-linked EFPA (CL-EFPA) was developed, inspired by a pantograph that restrains the EFPA three-dimensionally using the proposed link mechanism. The proposed CL-EFPA consists of three EFPAs and a cross-linking mechanism for integrating each EFPA circumference. The pushing force of the CL-EFPA is approximately 3.0 times compared with that generated by the previous EFPA with plates to restrain its plane. To perform various bending motions, attitude control was performed using an analytical model and a system that included valves, sensors, and controllers.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0001-86863432025Progress in silicon-based materials for emerging solar-powered green hydrogen (H2) production103558ENAminulIslamDepartment of Petroleum and Mining Engineering, Jashore University of Science and TechnologyMd. TarekulIslamDepartment of Leather Engineering, Faculty of Mechanical Engineering, Khulna University of Engineering and TechnologySiow HwaTeoIndustrial Chemistry Program, Faculty of Science and Natural Resources, Universiti Malaysia SabahHasanMahmudBangladesh Energy and Power Research Council (BEPRC)A.M.SwarazDepartment of Genetic Engineering and Biotechnology, Jashore University of Science and TechnologyAriyan IslamRehanDepartment of Chemistry, School of Science, The University of TokyoAdiba IslamRaseeDepartment of Chemistry, Graduate School of Science, Osaka UniversityKhadiza TulKubraDepartment of Chemistry, Graduate School of Science, Osaka UniversityMd. MunjurHasanDepartment of Chemistry, Graduate School of Science, Osaka UniversityMd. ShadSalmanInstitute for Chemical Research, Kyoto UniversityR.M.WaliullahInstitute for Chemical Research, Kyoto UniversityMd. NazmulHasanDepartment of Chemistry, School of Science, The University of TokyoMd. ChanmiyaSheikhDivision of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama UniversityTetsuyaUchidaDivision of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama UniversityMrs EtiAwualDepartment of Chemistry, Graduate School of Science, Osaka UniversityMohammed SohrabHossainDepartment of Chemistry, Graduate School of Science, Osaka UniversityHusseinZnadWestern Australian School of Mines: Minerals, Energy and Chemical Engineering, Curtin UniversityMd. RabiulAwualWestern Australian School of Mines: Minerals, Energy and Chemical Engineering, Curtin UniversityThe imperative demand for sustainable and renewable energy solutions has precipitated profound scientific investigations into photocatalysts designed for the processes of water splitting and hydrogen fuel generation. The abundance, low toxicity, high conductivity, and cost-effectiveness of silicon-based compounds make them attractive candidates for hydrogen production, driving ongoing research and technological advancements. Developing an effective synthesis method that is simple, economically feasible, and environmentally friendly is crucial for the widespread implementation of silicon-based heterojunctions for sustainable hydrogen production. Balancing the performance benefits with the economic and environmental considerations is a key challenge in the development of these systems. The specific performance of each catalyst type can vary depending on the synthesis method, surface modifications, catalyst loading, and reaction conditions. The confluence of high crystallinity, reduced oxygen concentration, and calcination temperature within the silicon nanoparticle has significantly contributed to its noteworthy hydrogen evolution rate. This review provides an up-to-date evaluation of Si-based photocatalysts, summarizing recent developments, guiding future research directions, and identifying areas that require further investigation. By combining theoretical insights and experimental findings, this review offers a comprehensive understanding of Si-based photocatalysts for water splitting. Through a comprehensive analysis, it aims to elucidate existing knowledge gaps and inspire future research directions towards optimized photocatalytic performance and scalability, ultimately contributing to the realization of sustainable hydrogen generation.No potential conflict of interest relevant to this article was reported.Fuji Technology Press Ltd.Acta Medica Okayama1883-80493712025Fan-Shaped Pneumatic Soft Actuator that Can Operate Bending Motion for Ankle-Joint Rehabilitation Device4353ENSoShimookaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityHirosatoYokoyaGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityMasanoriHamadaDepartment of Rehabilitation Medicine, Okayama University HospitalShunShiomiDepartment of Rehabilitation Medicine, Okayama University HospitalTakenoriUeharaDepartment of Orthopaedic Surgery, NHO Okayama Medical CenterTakahiroHirayamaDepartment of Emergency, Critical Care and Disaster Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityTetsushiKamegawaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityNowadays, owing to declining birthrates and an aging population, patients and the elderly requiring rehabilitation are not getting enough physical activity. In addressing this issue, devices for rehabilitating them have been researched and developed. However, rehabilitation devices are almost exclusively used for patients who can get up, rather than those who are bedridden. In this study, we aim to develop a rehabilitation device that can provide passive exercise for bedridden patients. The ankle joint was selected as the target joint because the patients who have undergone surgery for cerebrovascular disease remain bedridden, and early recovery in the acute stage is highly desirable. We proposed and tested a fan-shaped pneumatic soft actuator (FPSA) that can expand and bend stably at angles when supply pressure is applied as an actuator for a rehabilitation device to encourage patient exercise. However, the previous FPSA’s movement deviates from the arch of the foot owing to increased supply pressure. In the ideal case, FPSA should push the arch of the foot in an arc motion. This study proposes and tests the FPSA that can operate a bending motion to provide passive exercise to the ankle joint using tensile springs and a winding mechanism powered by a servo motor. The proposed FPSA has a significant advantage of exhibiting no hysteresis in its pressure-displacement characteristics. The configuration and static analytical model of the improved FPSA are described.No potential conflict of interest relevant to this article was reported.American Chemical Society (ACS)Acta Medica Okayama2691-3704522025Mechanistic Insights Into Oxidative Response of Heat Shock Factor 1 Condensates606617ENSoichiroKawagoeInstitute of Advanced Medical Sciences, Tokushima UniversityMotonoriMatsusakiInstitute of Advanced Medical Sciences, Tokushima UniversityTakuyaMabuchiFrontier Research Institute for Interdisciplinary Sciences, Tohoku UniversityYutoOgasawaraDepartment of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityKazunoriWatanabeDepartment of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityKoichiroIshimoriDepartment of Chemistry, Faculty of Science, Hokkaido UniversityTomohideSaioInstitute of Advanced Medical Sciences, Tokushima UniversityHeat shock factor 1 (Hsf1), a hub protein in the stress response and cell fate decisions, senses the strength, type, and duration of stress to balance cell survival and death through an unknown mechanism. Recently, changes in the physical property of Hsf1 condensates due to persistent stress have been suggested to trigger apoptosis, highlighting the importance of biological phase separation and transition in cell fate decisions. In this study, the mechanism underlying Hsf1 droplet formation and oxidative response was investigated through 3D refractive index imaging of the internal architecture, corroborated by molecular dynamics simulations and biophysical/biochemical experiments. We found that, in response to oxidative conditions, Hsf1 formed liquid condensates that suppressed its internal mobility. Furthermore, these conditions triggered the hyper-oligomerization of Hsf1, mediated by disulfide bonds and secondary structure stabilization, leading to the formation of dense core particles in the Hsf1 droplet. Collectively, these data demonstrate how the physical property of Hsf1 condensates undergoes an oxidative transition by sensing redox conditions to potentially drive cell fate decisions.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama1598-23512552025Hydrogen Embrittlement Characteristics of Austenitic Stainless Steels After Punching Process11581167ENMitsuhiroOkayasuDepartment of Mechanical and Systems Engineering, Okayama UniversityXichangLiDepartment of Mechanical and Systems Engineering, Okayama UniversityTomohisaKawakamiSHOYO SANGYO Co., Ltd.This study investigates the influence of microstructural characteristics on the hydrogen embrittlement of SUS304 austenitic stainless steel. The investigation utilized SUS304 sheets with a thickness of 1.5 mm, which were processed by punching with an 8 mm diameter to make specimens. Severe plastic deformation was localized near the punching edge, with the extent of deformation determined by the punching speed. Slower punching speeds induced more pronounced plastic strain, which was closely associated with work hardening and strain-induced martensitic (SIM) transformation. The SIM phase was predominantly observed within a depth of approximately 0.1 mm from the punched edge when processed at a punching speed of 0.25 mm/s, corresponding to roughly 10% of the cross-sectional area of the sample. These microstructural changes led to a significant reduction in tensile and fatigue strength, thereby exacerbating susceptibility to severe hydrogen embrittlement, despite the limited extent of microstructural alteration. Based on these findings, a modified Goodman diagram for SUS304 austenitic stainless steel, incorporating mechanical properties and hydrogen embrittlement behavior, was proposed.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama1939-59812032025Study of the Mechanical Properties of Al–Mg ADC6 Aluminum Alloy Produced by Unidirectional Casting Under Various Cooling Rates19511963ENS.TakeuchiGraduate School of Environment, Life, Natural Science and Technology, Okayama UniversityM.OkayasuDepartment of Mechanical Systems and Engineering, Okayama UniversityTo create the high strength and high ductility of Al–Mg-based aluminum alloy (JIS–ADC6), ADC6 samples were produced by the unidirectional continuous casting (HMC). The HMC process was conducted with direct water cooling to melt ADC6, which can make fine microstructures and control crystal orientation. The cast samples were prepared under various cooling rates (CRs): 6.3, 34, and 62 K/s. The microstructure and crystal orientation of the samples were altered with CR. At CRs of 34 K/s and 62 K/s, the α-Al phases and intermetallic compounds, e.g., Mg2Si and Al15(Fe, Mn)3Si2, became finer and more spherical. The secondary dendrite arm spacing for the sample at 62 K/s was 8.7 µm—more than 70% smaller than the ADC6 sample (ingot) made by a gravity casting process. Notably, at a CR of 34 K/s, the crystal orientation was predominantly arranged with the (101) plane. Tensile properties—ultimate tensile strength (σUTS), 0.2% proof stress (σ0.2), and failure strain (εf)—varied with the CR. The tensile strength (σUTS and σ0.2) consistently increased with increasing the CR. The improvement in the tensile strength resulted from the refined microstructures, such as the α-Al phase and intermetallic compounds. Similarly, the failure strain also increased with increasing CR, which was severely affected by the finer and more spherical intermetallic compounds. In this case, the εf value of the sample at 34 K/s was, however, slightly higher than that at 62 K/s, due to more uniformly organized crystal orientation, while their ductility was much higher than that of the gravity cast sample. The tensile properties in detail were further analyzed using their failure characteristics.No potential conflict of interest relevant to this article was reported.Life Science Alliance, LLCActa Medica Okayama2575-10777122024Chromosome-specific barcode system with centromeric repeat in cultivated soybean and wild progenitore202402802ENAhmet LTekDepartment of Agricultural Genetic Engineering, Ayhan Şahenk Faculty of Agricultural Sciences and Technologies, Niğde Ömer Halisdemir UniversityKiyotakaNagakiInstitute of Plant Science and Resources, Okayama UniversityHümeyraYıldız AkkamışDepartment of Agricultural Genetic Engineering, Ayhan Şahenk Faculty of Agricultural Sciences and Technologies, Niğde Ömer Halisdemir UniversityKeisukeTanakaNODAI Genome Research Center, Tokyo University of AgricultureHisatoKobayashiNODAI Genome Research Center, Tokyo University of AgricultureWild soybean Glycine soja is the progenitor of cultivated soybean Glycine max. Information on soybean functional centromeres is limited despite extensive genome analysis. These species are an ideal model for studying centromere dynamics for domestication and breeding. We performed a detailed chromatin immunoprecipitation analysis using centromere-specific histone H3 protein to delineate two distinct centromeric DNA sequences with unusual repeating units with monomer sizes of 90–92 bp (CentGm-1) and 413-bp (CentGm-4) shorter and longer than standard nucleosomes. These two unrelated DNA sequences with no sequence similarity are part of functional centromeres in both species. Our results provide a comparison of centromere properties between a cultivated and a wild species under the effect of the same kinetochore protein. Possible sequence homogenization specific to each chromosome could highlight the mechanism for evolutionary conservation of centromeric properties independent of domestication and breeding. Moreover, a unique barcode system to track each chromosome is developed using CentGm-4 units. Our results with a unifying centromere composition model using CentGm-1 and CentGm-4 superfamilies could have far-reaching implications for comparative and evolutionary genome research.No potential conflict of interest relevant to this article was reported.American Chemical Society (ACS)Acta Medica Okayama2637-61057152025Tailoring Mechanical Properties and Ionic Conductivity of Poly(ionic liquid)-Based Ion Gels by Tuning Anion Compositions1015110159ENTakaichiWatanabeDepartment of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama UniversityYunaMizutaniDepartment of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama UniversityCarlos G.LopezMaterial Science and Engineering Department, The Pennsylvania State University, 80 Pollock Road, State CollegeTsutomuOnoDepartment of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama UniversityPoly(ionic liquid) (PIL)-based ion gels have emerged as promising materials for advanced electrochemical applications because of their excellent miscibility with ionic liquids (IL), tunable mechanical properties, and high ionic conductivity. Despite extensive studies on PIL-based ion gels, a comprehensive understanding of how different anion combinations in the system affect physicochemical properties is lacking. In this study, we systematically investigate the effect of different anion species, such as bis(trifluoromethanesulfonyl)imide (TFSI) and hexafluorophosphate (PF6), on the mechanical, viscoelastic, and ion conductive behaviors of PIL-based ion gels. We investigate the interplay between anion size, packing density, and polymer segmental dynamics by varying the anion composition in both the PIL network and IL component. Rheological analysis and uniaxial tensile testing results indicate that PF6-containing ion gels exhibit enhanced higher Young’s modulus because of their restricted chain mobility resulting in higher glass transition temperature (Tg). In addition, we confirm the anion exchange between PIL and IL during gel preparation and find that the mechanical and ion conductive properties of the gels are governed by the total molar ratio of anions in the gels. Our findings highlight that tuning the anion composition in PIL-based ion gels provides an effective strategy to tailor their performance, with potential applications for flexible electronics and solid-state electrochemical devices.No potential conflict of interest relevant to this article was reported.WileyActa Medica Okayama0952-34803892025Ultrahigh‐Field MR‐Compatible Mechanical Tactile Stimulator for Investigating Somatosensory Processing in Small‐Bodied Animalse70105ENChenyuWangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityHirohikoImaiInnovation Research Center for Quantum Medicine, Gifu University School of MedicineMasakiFukunagaSection of Brain Function Information, National Institute for Physiological SciencesHirokiYamamotoGraduate School of Human and Environmental Studies, Kyoto UniversityYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityKazuhikoSekiDepartment of Neurophysiology, National Center of Neurology and PsychiatryTakashiHanakawaDepartment of Integrated Neuroanatomy and Neuroimaging, Kyoto University Graduate School of MedicineTatsuyaUmedaDepartment of Integrated Neuroanatomy and Neuroimaging, Kyoto University Graduate School of MedicineJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityCommon marmosets (Callithrix jacchus), small-bodied New World primates that share similar sensory processing pathways with human beings, have gained great interests. Their small body size allows imaging of brain activity with high spatial resolution and on a whole-brain scale using ultrahigh-field (UHF) magnetic resonance imaging (MRI) scanners. However, the strong magnetic field and the small size of the hand and forearm pose challenges in delivering tactile stimulation during fMRI experiments. In the present study, we developed an MR-compatible tactile dual-point stimulator to provide high-precision mechanical stimulation for exploring somatosensory processing in small-bodied animals. The study population consisted of a water phantom and three male common marmosets. Cerebral blood volume (CBV) weighted fMRI data were obtained with a gradient echo (GE), echo-planar imaging (EPI) sequence at 7T scanner. The output performance of the device was tested by a pressure sensor. The MR compatibility of the device was verified by measuring the temporal signal-to-noise ratio (tSNR) of a water phantom. To test the effectiveness of tactile stimulation, we conducted block designed tactile stimulation experiments on marmosets. A one-way repeated measures ANOVA was conducted for comparing the tSNR results. We performed one-sample t-tests to investigate the negative response of the forearm and hand stimulation with a threshold of t > 1.96 (p < 0.05). Performance tests revealed that mechanical stimulation (averaged force: 31.69 g) was applied with a delay of 12 ms. Phantom experiments confirmed that there was no significant difference in the tSNR among three (10 Hz, 1 Hz, and no-stimulus) conditions (F (2, 798) = 0.71, p = 0.49). The CBV activity results showed that the stimulator successfully elicited hand and forearm somatosensory activations in primary somatosensory areas. These results indicated that the device is well suited for small-bodied animal somatosensory studies.No potential conflict of interest relevant to this article was reported.MDPI AGActa Medica Okayama1467-30454762025Artificial Intelligence Approach in Machine Learning-Based Modeling and Networking of the Coronavirus Pathogenesis Pathway466ENShihoriTanabeDivision of Risk Assessment, Center for Biological Safety and Research, National Institute of Health SciencesSabinaQuaderInnovation Centre of NanoMedicine (iCONM), Kawasaki Institute of Industrial PromotionRyuichiOnoDivision of Cellular and Molecular Toxicology, Center for Biological Safety and Research, National Institute of Health SciencesHiroyoshi Y.TanakaDepartment of Pharmaceutical Biomedicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityAkihisaYamamotoDepartment of Mechanical Systems Engineering, Graduate School of Systems Design Tokyo Metropolitan UniversityMotohiroKojimaDepartment of Surgical Pathology, Kyoto Prefecture University of MedicineEdward J.PerkinsUS Army Engineer Research and Development CenterHoracioCabralDepartment of Bioengineering, Graduate School of Engineering, The University of TokyoThe coronavirus pathogenesis pathway, which consists of severe acute respiratory syndrome (SARS) coronavirus infection and signaling pathways, including the interferon pathway, the transforming growth factor beta pathway, the mitogen-activated protein kinase pathway, the apoptosis pathway, and the inflammation pathway, is activated upon coronaviral infection. An artificial intelligence approach based on machine learning was utilized to develop models with images of the coronavirus pathogenesis pathway to predict the activation states. Data on coronaviral infection held in a database were analyzed with Ingenuity Pathway Analysis (IPA), a network pathway analysis tool. Data related to SARS coronavirus 2 (SARS-CoV-2) were extracted from more than 100,000 analyses and datasets in the IPA database. A total of 27 analyses, including nine analyses of SARS-CoV-2-infected human-induced pluripotent stem cells (iPSCs) and iPSC-derived cardiomyocytes and fibroblasts, and a total of 22 analyses of SARS-CoV-2-infected lung adenocarcinoma (LUAD), were identified as being related to “human” and “SARS coronavirus 2” in the database. The coronavirus pathogenesis pathway was activated in SARS-CoV-2-infected iPSC-derived cells and LUAD cells. A prediction model was developed in Python 3.11 using images of the coronavirus pathogenesis pathway under different conditions. The prediction model of activation states of the coronavirus pathogenesis pathway may aid in treatment identification.No potential conflict of interest relevant to this article was reported.Oxford University Press (OUP)Acta Medica Okayama1040-465136122024The leucine-rich repeat receptor kinase QSK1 regulates PRR-RBOHD complexes targeted by the bacterial effector HopF2Pto49324951ENYukihisaGotoPlant Immunity Research Group, RIKEN Center for Sustainable Resource Science (CSRS) YasuhiroKadotaPlant Immunity Research Group, RIKEN Center for Sustainable Resource Science (CSRS) MalickMbengueThe Sainsbury Laboratory, University of East AngliaJennifer DLewisDepartment of Cell and System Biology, Centre for the Analysis of Genome Function and Evolution, University of TorontoHidenoriMatsuiGraduate School of Environmental and Life Science, Okayama UniversityNorikoMakiPlant Immunity Research Group, RIKEN Center for Sustainable Resource Science (CSRS) Bruno Pok ManNgouPlant Immunity Research Group, RIKEN Center for Sustainable Resource Science (CSRS) JanSklenarThe Sainsbury Laboratory, University of East AngliaPaulDerbyshireThe Sainsbury Laboratory, University of East AngliaArisaShibataPlant Immunity Research Group, RIKEN Center for Sustainable Resource Science (CSRS) YasunoriIchihashiPlant Immunity Research Group, RIKEN Center for Sustainable Resource Science (CSRS) David SGuttmanDepartment of Cell and System Biology, Centre for the Analysis of Genome Function and Evolution, University of TorontoHirofumiNakagamiPlant Proteomics Research Unit, RIKEN CSRSTakamasaSuzukiCollege of Bioscience and Biotechnology, Chubu UniversityFrank L HMenkeThe Sainsbury Laboratory, University of East AngliaSilkeRobatzekThe Sainsbury Laboratory, University of East AngliaDarrellDesveauxDepartment of Cell and System Biology, Centre for the Analysis of Genome Function and Evolution, University of TorontoCyrilZipfelInstitute of Plant and Microbial Biology, Zurich-Basel Plant Science Center, University of ZurichKenShirasuPlant Immunity Research Group, RIKEN Center for Sustainable Resource Science (CSRS) Plants detect pathogens using cell-surface pattern recognition receptors (PRRs) such as ELONGATION Factor-TU (EF-TU) RECEPTOR (EFR) and FLAGELLIN SENSING 2 (FLS2), which recognize bacterial EF-Tu and flagellin, respectively. These PRRs belong to the leucine-rich repeat receptor kinase (LRR-RK) family and activate the production of reactive oxygen species via the NADPH oxidase RESPIRATORY BURST OXIDASE HOMOLOG D (RBOHD). The PRR-RBOHD complex is tightly regulated to prevent unwarranted or exaggerated immune responses. However, certain pathogen effectors can subvert these regulatory mechanisms, thereby suppressing plant immunity. To elucidate the intricate dynamics of the PRR-RBOHD complex, we conducted a comparative coimmunoprecipitation analysis using EFR, FLS2, and RBOHD in Arabidopsis thaliana. We identified QIAN SHOU KINASE 1 (QSK1), an LRR-RK, as a PRR-RBOHD complex-associated protein. QSK1 downregulated FLS2 and EFR abundance, functioning as a negative regulator of PRR-triggered immunity (PTI). QSK1 was targeted by the bacterial effector HopF2Pto, a mono-ADP ribosyltransferase, reducing FLS2 and EFR levels through both transcriptional and transcription-independent pathways, thereby inhibiting PTI. Furthermore, HopF2Pto transcriptionally downregulated PROSCOOP genes encoding important stress-regulated phytocytokines and their receptor MALE DISCOVERER 1-INTERACTING RECEPTOR-LIKE KINASE 2. Importantly, HopF2Pto requires QSK1 for its accumulation and virulence functions within plants. In summary, our results provide insights into the mechanism by which HopF2Pto employs QSK1 to desensitize plants to pathogen attack.No potential conflict of interest relevant to this article was reported.岡山大学経済学会Acta Medica Okayama2433-41465712025イノベーションの発生源研究の再検討120ENQiHuangDaijiFujii10.18926/OER/69001 本論文は，イノベーションの発生源に関する先行研究を振り返り，「いつ」「どこで」「誰によって」イノベーションが生み出されるのかを理論的に考察することを目的とする。考察の結果，「B to B」の文脈においては，イノベーションの発生源が企業ユーザーへ移行するメカニズムとして，取引コスト理論，期待利益仮説，情報粘着性の仮説，企業内部の独自能力（吸収能力），および外部の産業構造（製品アーキテクチャ・エコシステム）といった複数の要素からなる経済的合理性の観点から分析されていることが明らかになった。一方，「B to C」の文脈では，エンドユーザーがイノベーションに向かう動機として，「ニッチ市場に対するメーカーの消極的な対応」「創造的活動の楽しさ」「ユーザーコミュニティとの繋がり」「知識・スキルの向上」など多種多様な要素が存在し，中でも創造的活動の楽しさが根源的な動機づけの1つであると確認された。一方で，イノベーターを突き動かす心理的要因をブラックボックス化したまま放置することは，単なる知的好奇心の問題に留まらず，社会科学としての経営学にとっても重要な問題であると考えられる。今後のイノベーションの発生源研究においては，起業家をはじめとするイノベーター個人の心理的側面にいかに目を向け，創造的活動におけるポジティブな感情が働くメカニズムをイノベーションの発生メカニズムにいかに位置づけるか，その研究アプローチの提示が求められる。No potential conflict of interest relevant to this article was reported.WileyActa Medica Okayama0014-5793599132025Characterization of molecular mechanisms of CaMKKα/1 oligomerization19141924ENShunUenoyamaApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityHayatoNittaDepartment of Applied Chemistry and Biotechnology, Faculty of Engineering, Okayama UniversitySatomiOhtsukaApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityMasakiMagariApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityFutoshiSuizuDepartment of Medical Technology, Kagawa Prefectural University of Health SciencesHiroshiTokumitsuCalcium/calmodulin-dependent protein kinase kinase (CaMKK) is an activating kinase for calcium/calmodulin-dependent protein kinase type 1 (CaMKI), calcium/calmodulin-dependent protein kinase type IV (CaMKIV), RAC-alpha serine/threonine-protein kinase (PKB), and AMP-activated protein kinase (AMPK) that has been reported to form an active oligomer in cells. Glutathione S-transferase (GST) pulldown assay from the extracts of COS-7 cells expressing GST- and His6-CaMKKα/1 mutants showed that the C-terminal region containing the autoinhibitory and calmodulin (CaM)-binding sequence (residues 438–463) is required for CaMKKα/1 homo-oligomerization. This was confirmed by the fact that the GST-CaMKKα/1 C-terminal domain (residues 435–505) directly interacted with EGFP-CaMKKα/1 residues 435–505 as well as with wild-type CaMKKα/1. Notably, once oligomerized in cells, CaMKKα/1 is neither exchangeable between the oligomeric complexes nor dissociated by Ca2+/CaM binding. These results support stable oligomerization of CaMKK in the cells by intermolecular self-association of its C-terminal region containing a regulatory domain.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama2041-17231512024A high-protein diet-responsive gut hormone regulates behavioral and metabolic optimization in Drosophila melanogaster10819ENYutoYoshinariMetabolic Regulation and Genetics, Institute for Molecular and Cellular Regulation, Gunma UniversityTakashiNishimuraMetabolic Regulation and Genetics, Institute for Molecular and Cellular Regulation, Gunma UniversityTaishiYoshiiGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityShuKondoDepartment of Biological Science and Technology, Faculty of Advanced Engineering, Tokyo University of ScienceHiromuTanimotoGraduate School of Life Sciences, Tohoku UniversityTomoeKobayashiDivision of Molecular Genetics, Shigei Medical Research InstituteMakotoMatsuyamaDivision of Molecular Genetics, Shigei Medical Research InstituteRyusukeNiwaLife Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of TsukubaProtein is essential for all living organisms; however, excessive protein intake can have adverse effects, such as hyperammonemia. Although mechanisms responding to protein deficiency are well-studied, there is a significant gap in our understanding of how organisms adaptively suppress excessive protein intake. In the present study, utilizing the fruit fly, Drosophila melanogaster, we discover that the peptide hormone CCHamide1 (CCHa1), secreted by enteroendocrine cells in response to a high-protein diet (HPD), is vital for suppressing overconsumption of protein. Gut-derived CCHa1 is received by a small subset of enteric neurons that produce short neuropeptide F, thereby modulating protein-specific satiety. Importantly, impairment of the CCHa1-mediated gut-enteric neuronal axis results in ammonia accumulation and a shortened lifespan under HPD conditions. Collectively, our findings unravel the crosstalk of gut hormone and neuronal pathways that orchestrate physiological responses to prevent and adapt to dietary protein overload.No potential conflict of interest relevant to this article was reported.Fuji Technology Press Ltd.Acta Medica Okayama1883-80221932025Study on the Grinding Temperature of Workpiece in Side Plunge Grinding Process337345ENLingxiaoGaoGraduate School of Natural Science and Technology, Okayama UniversityMotokiKuidaGraduate School of Natural Science and Technology, Okayama UniversityHiroyukiKodamaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityKazuhitoOhashiFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityGrinding is used to finish thrust metal attachment parts, such as crankshafts, which have both journal and thrust surfaces. In side plunge grinding, a thrust surface and a cylindrical surface of a shaft workpiece with collars are finished in a single plunge grinding process. However, the surface quality near the ground internal corner, where grinding fluid may not penetrate, can deteriorate, causing high residual stress and cracks owing to grinding heat. While it has been reported that quality issues at the inner corners of the ground surface can be mitigated by reducing the grinding point temperature through efficient cooling fluid supply, the mechanisms of grinding phenomena and heat generation in side plunge grinding are not yet fully understood. In this study, the variations in the grinding temperature at the thrust surface of a workpiece with a collar were experimentally investigated using a wire/workpiece thermocouple to clarify these phenomena. The results revealed a significant increase in the grinding temperature at the corners of the grinding zone. However, it slightly decreases as the thermocouple output approaches the center of the workpiece, indicating a slight effect of the grinding speed. The surface temperature of the workpiece in side plunge grinding is primarily influenced by the wheel depth-of-cut in the thrust direction. Additionally, the effect of workpiece rotational speed and grinding infeed speed on temperature distribution has been demonstrated.No potential conflict of interest relevant to this article was reported.American Chemical Society (ACS)Acta Medica Okayama0743-746341212025Unraveling the Molecular Mechanism of Transient Multilamellar Formation in Ethanol-Modified Vesicle Solutions1337213380ENKanaShibataDepartment of Materials Chemistry, Nagoya UniversityMasatoshiMaekiDivision of Applied Chemistry, Faculty of Engineering, Hokkaido UniversityManabuTokeshiDivision of Applied Chemistry, Faculty of Engineering, Hokkaido UniversityWataruShinodaResearch Institute for Interdisciplinary Science, Okayama UniversityA recent microfluidic-based small-angle X-ray scattering (SAXS) measurement intriguingly suggested the transient formation of multilamellar structures during the mixing of unilamellar vesicles with ethanol in an aqueous solution. This study explores a possible molecular mechanism underlying this phenomenon, primarily through coarse-grained molecular dynamics (CG-MD) simulations. We first examined lipid aggregate morphology as a function of ethanol concentration in an aqueous solution. Even though vesicles were observed in pure aqueous solution, increasing ethanol concentrations led to more frequent pore formation in vesicular membranes. At ethanol concentrations above 52%, vesicles destabilized and transformed into worm-like micelles. We hypothesized that the transient multilamellar structures might arise from vesicle stacking due to variations in the effective interactions between vesicles. However, a series of potential of mean force (PMF) calculations consistently showed repulsive interactions between vesicles, regardless of ethanol concentration, ruling out this possibility. In contrast, once lipid aggregates transformed into worm-like micelles, the PMF barrier between them dropped (∼5kBT), promoting fusion. Our CG-MD simulations further demonstrated that lipid aggregates (micelles) readily fused and grew in high ethanol concentrations. Upon subsequent exposure to lower ethanol levels, these enlarged aggregates reorganized into vesicles with internal lamellar structure─multilamellar vesicles. These findings suggest that the heterogeneous mixing of unilamellar vesicular solutions with ethanol in a microfluidic device plays a key role in the emergence of transient multilamellar structures.No potential conflict of interest relevant to this article was reported.Nature PortfolioActa Medica Okayama2399-3642812025TRPV2 mediates stress resilience in mouse cardiomyocytes715ENYubingDongDepartment of Cardiovascular Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityGuohaoWangDepartment of Cardiovascular Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityYoshihiroUjiharaDepartment of Electrical and Mechanical Engineering, Graduate School of Engineering, Nagoya Institute of TechnologyYanzhuChenDepartment of Cardiovascular Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityMasashiYoshidaDepartment of Chronic Kidney Disease and Cardiovascular Disease, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical SciencesKazufumiNakamuraDepartment of Cardiovascular Medicine, Okayama University Faculty of Medicine, Dentistry and Pharmaceutical SciencesKimiakiKatanosakaDepartment of Biomedical Sciences, College of Life and Health Sciences, Chubu UniversityKeijiNaruseDepartment of Cardiovascular Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityYukiKatanosakaDepartment of Cardiovascular Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityThe heart dynamically compensates for haemodynamic stress, but how this resilience forms during cardiac growth is not clear. Using a temporally inducible, cardiac-specific knockout in mice we show that the Transient receptor potential vanilloid family 2 (TRPV2) channel is crucial for the maturation of cardiomyocyte stress resilience. TRPV2 defects in growing hearts lead to small morphology, abnormal intercalated discs, weak contractility, and low expression of serum response factor and Insulin-like growth factor-1 (IGF-1) signalling. Individual cardiomyocytes of TRPV2-deficient hearts show reduced contractility with abnormal Ca2+ handling. In cultured neonatal cardiomyocytes, mechanical Ca2+ response, excitation-contraction coupling, sarcoplasmic reticulum Ca2+ content, actin formation, nuclear localisation of Myocyte enhancer factor 2c, and IGF-1 expression require TRPV2. TRPV2-deficient hearts show a defective response to dobutamine stress and no compensatory hypertrophic response to phenylephrine administration, but no stress response to pressure overload. These data suggest TRPV2 mediates the maturation of cardiomyocyte stress resilience, and will advance therapeutic interventions and drug discovery for heart disease.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2227-70801342025An Implementation of Creep Test Assisting System with Dial Gauge Needle Reading and Smart Lighting Function for Laboratory Automation139ENDezhengKongGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityNobuoFunabikiGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityShihaoFangGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityMitsuhiroNopriantoGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityMitsuhiroOkayasuGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityPradiniPuspitaningayuDepartment of Electrical Engineering, Universitas Negeri SurabayaFor decades, analog dial gauges have been essential for measuring and monitoring data at various industrial instruments including production machines and laboratory equipment. Among them, we focus on the instrument for creep test in a mechanical engineering laboratory, which evaluates material strength under sustained stress. Manual reading of gauges imposes significant labor demands, especially in long-duration tests. This burden further increases under low-lighting environments, where poor visibility can lead to misreading data points, potentially compromising the accuracy of test results. In this paper, to address the challenges, we implement a creep test assisting system that possesses the following features: (1) to save the installation cost, a web camera and Raspberry Pi are employed to capture images of the dial gauge and automate the needle reading by image processing in real time, (2) to ensure reliability under low-lighting environments, a smart lighting mechanism is integrated to turn on a supplementary light when the dial gauge is not clearly visible, and (3) to allow a user to stay in a distant place from the instrument during a creep test, material break is detected and the corresponding message is notified to a laboratory staff using LINE automatically. For evaluations, we install the implemented system into a material strength measuring instrument at Okayama University, Japan, and confirm the effectiveness and accuracy through conducting experiments under various lighting conditions.No potential conflict of interest relevant to this article was reported.SpringerActa Medica Okayama1435-02117112025Quantitative assessment of adhesive effects on partial and full compressive strength of LVL in the edge-wise direction19ENRyutaroSudoOkayama University, Graduate School of Environmental, Life, Natural Science and TechnologyKohtaMiyamotoForestry and Forest Products Research InstituteHirofumiIdoForestry and Forest Products Research InstituteLaminated wood-based materials have been widely developed, and the laminating process and adhesive itself have been reported to enhance performance beyond the sum of the individual layers' performance. This phenomenon is particularly notable under loads applied in the "edge-wise direction", where each layer bears stress collectively. These combined effects are referred to as the "adhesive effect". Strength under partial compressive loads is critical in timber engineering, as partial compressive stress generates complex stress distributions influenced by boundary conditions. The adhesive effect may also be impacted by these conditions. The aim of this study was to quantitatively and directly evaluate the adhesive effect under partial and full compressive loads using various parameters. The strength of laminated veneer lumber (LVL) with adhesive was compared to that of simply layered veneers without adhesive to assess the adhesive effect. Three mechanisms contributing to the adhesive effect were proposed: Mechanism I, caused by the deformation of the adhesive layer independently from the veneers; Mechanism II, resulting from the adhesive impregnating the veneers; and Mechanism III, arising from the reinforcement provided by adjacent veneers. The results suggested the following: (i) Mechanism I had minimal impact, as the fiber direction and the presence of additional length showed strong and slight effects on the adhesive effect, respectively; (ii) Mechanism II contributed to preventing crack propagation and altering the relationships among mechanical properties, with its effectiveness increasing as the adhesive weight increased; and (iii) Mechanism III functioned as a crossband effect, reinforcing weaknesses caused by the slope of the grain and the angle of the annual rings.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X7922025Association between the Pretreatment Body Mass Index and Anamorelin’s Efficacy in Patients with Cancer Cachexia: A Retrospective Cohort Study6573ENMasatoshiMakiDepartment of Hospital Pharmacy, NHO Fukuyama Medical CenterRyoTakadaDepartment of Hospital Pharmacy, NHO Fukuyama Medical CenterTomoyukiIshigoDepartment of Pharmacy, Sapporo Medical University HospitalMikiFujiwaraDepartment of Hospital Pharmacy, NHO Fukuyama Medical CenterYokoTakahashiDepartment of Hospital Pharmacy, NHO Fukuyama Medical CenterShinyaOtsukaDepartment of Surgery, NHO Fukuyama Medical CenterKojiTamuraDepartment of Hospital Pharmacy, NHO Fukuyama Medical CenterTerutakaHamaokaDepartment of Hospital Pharmacy, NHO Fukuyama Medical CenterOriginal Article/10.18926/AMO/68644Anamorelin (ANAM) is used to treat cancer-associated cachexia, a syndrome involving muscle loss and anorexia. The timing of the initiation of ANAM treatment is crucial to its efficacy. Although the body mass index (BMI) is a diagnostic criterion for cancer cachexia, no studies have explored its association with ANAM efficacy. We conducted a single-center, retrospective cohort study to investigate the association between the pre-treatment BMI and ANAM efficacy in patients with cancer-associated cachexia (n=47). The ANAM treatment was considered effective if the patient’s appetite improved within 30 days of treatment initiation. We calculated a BMI cutoff value (19.5 kg/m2) and used it to divide the patients into high- and low-BMI groups. Their background, clinical laboratory values, cancer types, and treatment lines were investigated. Twenty (42.6%) had a high BMI (≥ 19.5 kg/m2) and 27 (57.4%) had a low BMI (< 19.5 kg/m2). High BMI was significantly associated with ANAM effectiveness (odds ratio 7.86, 95% confidence interval 1.99-31.00, p=0.003). Together these results indicate that it is beneficial to initiate ANAM treatment before a patient’s BMI drops below 19.5 kg/m2. Our findings will help advance cancer cachexia treatment and serve as a reference for clinicians to predict ANAM’s efficacy.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama1999-59031732025Facial Privacy Protection with Dynamic Multi-User Access Control for Online Photo Platforms124ENAndriSantosoGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversitySamsulHudaGreen Innovation Center, Okayama UniversityYutaKoderaGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityYasuyukiNogamiGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityIn the digital age, sharing moments through photos has become a daily habit. However, every face captured in these photos is vulnerable to unauthorized identification and potential misuse through AI-powered synthetic content generation. Previously, we introduced SnapSafe, a secure system for enabling selective image privacy focusing on facial regions for single-party scenarios. Recognizing that group photos with multiple subjects are a more common scenario, we extend SnapSafe to support multi-user facial privacy protection with dynamic access control designed for online photo platforms. Our approach introduces key splitting for access control, an owner-centric permission system for granting and revoking access to facial regions, and a request-based mechanism allowing subjects to initiate access permissions. These features ensure that facial regions remain protected while maintaining the visibility of non-facial content for general viewing. To ensure reproducibility and isolation, we implemented our solution using Docker containers. Our experimental assessment covered diverse scenarios, categorized as "Single", "Small", "Medium", and "Large", based on the number of faces in the photos. The results demonstrate the system's effectiveness across all test scenarios, consistently performing face encryption operations in under 350 ms and achieving average face decryption times below 286 ms across various group sizes. The key-splitting operations maintained a 100% success rate across all group configurations, while revocation operations were executed efficiently with server processing times remaining under 16 ms. These results validate the system's capability in managing facial privacy while maintaining practical usability in online photo sharing contexts.No potential conflict of interest relevant to this article was reported.American Association for Cancer Research (AACR)Acta Medica Okayama0008-54728562025Myeloid Cells Induce Infiltration and Activation of B Cells and CD4+ T Follicular Helper Cells to Sensitize Brain Metastases to Combination Immunotherapy10821096ENToshifumiNinomiyaDepartment of Tumor Microenvironment, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityNaoyaKemmotsuDepartment of Tumor Microenvironment, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityFumiakiMukoharaDepartment of Tumor Microenvironment, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityMasakiMagariApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityAiMiyamotoMedical Protein Engineering, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYoukiUedaDepartment of Tumor Microenvironment, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityTakamasaIshinoDepartment of Tumor Microenvironment, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityJojiNagasakiDepartment of Tumor Microenvironment, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityTomohiroFujiwaraDepartment of Orthopaedic Surgery, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama UniversityHidetakaYamamotoDepartment of Pathology and Oncology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityHidetoshiHayashiDepartment of Medical Oncology, Kindai University Faculty of MedicineKotaTachibanaDepartment of Dermatology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama UniversityJojiIshidaDepartment of Neurological Surgery, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityYoshihiroOtaniDepartment of Neurological Surgery, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityShotaTanakaDepartment of Neurological Surgery, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityShinichiToyookaDepartment of General Thoracic Surgery, Breast and Endocrinological Surgery, Faculty of Medicine, Dentistry and Pharmaceutical Science, Okayama UniversityIsamuOkamotoDepartment of Respiratory Medicine, Graduate School of Medical Sciences, Kyushu UniversityYosukeTogashiDepartment of Tumor Microenvironment, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityBrain metastasis is a poor prognostic factor in patients with cancer. Despite showing efficacy in many extracranial tumors, immunotherapy with anti–PD-1 mAb or anti–CTLA4 mAb seems to be less effective against intracranial tumors. Promisingly, recent clinical studies have reported that combination therapy with anti–PD-1 and anti–CTLA4 mAbs has a potent antitumor effect on brain metastasis, highlighting the need to elucidate the detailed mechanisms controlling the intracranial tumor microenvironment (TME) to develop effective immunotherapeutic strategies. In this study, we analyzed the tumor-infiltrating lymphocytes in murine models of brain metastasis that responded to anti–CTLA4 and anti–PD-1 mAbs. Activated CD4+ T follicular helper (TFH) cells with high CTLA4 expression characteristically infiltrated the intracranial TME, which were activated by combination anti–CTLA4 and anti–PD-1 treatment. The loss of TFH cells suppressed the additive effect of CTLA4 blockade on anti–PD-1 mAb. B-cell–activating factor belonging to the TNF family (BAFF) and a proliferation-inducing ligand (APRIL) produced by abundant myeloid cells, particularly CD80hiCD206lo proinflammatory M1-like macrophages, in the intracranial TME induced B-cell and TFH-cell infiltration and activation. Furthermore, the intracranial TME of patients with non–small cell lung cancer featured TFH- and B-cell infiltration as tertiary lymphoid structures. Together, these findings provide insights into the immune cell cross-talk in the intracranial TME that facilitates an additive antitumor effect of CTLA4 blockade with anti–PD-1 treatment, supporting the potential of a combination immunotherapeutic strategy for brain metastases.<br>
Significance: B-cell and CD4+ T follicular helper cell activation via BAFF/APRIL from abundant myeloid cells in the intracranial tumor microenvironment enables a combinatorial effect of CTLA4 and PD-1 blockade in brain metastases.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama1661-65962632025LRP4 and Agrin Are Modulated by Cartilage Degeneration and Involved in β-Catenin Signaling in Human Articular Chondrocytes1007ENShuichiNaniwaDepartment of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Okayama UniversityKeiichiroNishidaLocomotive Pain Center, Okayama University HospitalAkiYoshidaDepartment of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Okayama UniversityYoshihisaNasuLocomotive Pain Center, Okayama University HospitalRyuichiNakaharaLocomotive Pain Center, Okayama University HospitalTakashiOhtsukiDepartment of Medical Technology, Graduate School of Health Sciences, Okayama UniversityYoshifumiHottaDepartment of Orthopaedic Surgery, Sayo Central HospitalNoriyukiShimizuDepartment of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Okayama UniversityChinatsuIchikawaDepartment of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Okayama UniversityDetingLinDepartment of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Okayama UniversityNoriakiOtsukaDepartment of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Okayama UniversityToshifumiOzakiDepartment of Orthopaedic Surgery, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityWe investigated the roles of low-density lipoprotein receptor-related protein (LRP) 4 and its ligand Agrin in the pathophysiology of cartilage degeneration. Immunohistochemical analysis of human normal articular cartilage and cartilage tissues from patients with osteoarthritis (OA) obtained during surgery of the knee joint showed marked LRP4 expression in the early stages of OA, which then decreased with cartilage degeneration, whereas Agrin was consistently increased with cartilage degeneration. In normal human articular chondrocytes (NHACs), mild cyclic tensile strain (CTS) (0.5 Hz, 5% elongation, 2 h) increased the expression of LRP4 and aggrecan (ACAN), while intense CTS (0.5 Hz, 10% elongation, 6 h) increased the expression of Agrin without affecting LRP4 expression. Treatment with recombinant human (rh) Agrin downregulated the mRNA expression of LRP4 and ACAN, but upregulated the expression of LRP5/6, SRY-box transcription factor 9 (SOX9), Runt-related transcription factor 2 (RUNX2), and a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4). Immunocytochemistry and Western blot analysis showed that rhAgrin treatment upregulated the expression of β-catenin and SOX9. Agrin knockdown by siAGRN transfection partially reduced the nuclear protein expression of β-catenin, which was increased with intense CTS. LRP4 knockdown by siLRP4 transfection increased the expression of LRP5/6, SOX9, RUNX2, ADAMTS-4, and Agrin. These results suggested that intense CTS increases the expression of Agrin, which might interfere with the role of LRP4 in the inhibition of LRP5/6 and their downstream β-catenin signaling, leading to cartilage degeneration.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama1350-63071702025Evaluation of small fatigue crack deflection behavior on copper using electron backscatter diffraction and crystal plasticity finite element analysis109242ENJintaArakawaGraduate School of Natural Science and Technology, Okayama UniversityRyoYabukiGraduate School of Natural Science and Technology, Okayama UniversityTakeshiUemoriGraduate School of Natural Science and Technology, Okayama UniversityMasatoItoInnovation Center, Mitsubishi Materials CorporationKenichiYaguchiInnovation Center, Mitsubishi Materials CorporationIn this study, it was conducted to observe the propagation behavior of small fatigue cracks generated on the surface of α-brass and pure copper, using an electrodynamic plane bending fatigue testing machine. The EBSD method was also used to analyze the crystal orientation near the bottom of the notch on the surface of the test piece. For each slip system of the grain, we calculated the slip factor, defined as the ratio of resolved shear stresses that considers the singular stress field at the crack tip, and investigated the relationship between the propagation behavior of small cracks and the slip factor. Furthermore, we performed a crystal plasticity finite element analysis (CP-FEM) using a crystal plasticity FEM model created from the grains obtained by the EBSD method to predict the deflection behavior of small fatigue cracks when propagating through the grain boundaries. The results indicated that when a crack propagates across a grain boundary, it is difficult to predict the deflection behavior using slip factors, however, the deflection behavior of a crack can be predicted from the resolved shear stress calculated using CP-FEM, which considers the mechanical interactions between crystal grains.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2076-342514122024The Impact of Selective Spatial Attention on Auditory-Tactile Integration: An Event-Related Potential Study1258ENWeichaoAnGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityNanZhangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityShengnanLiGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJinglongWuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityBackground: Auditory-tactile integration is an important research area in multisensory integration. Especially in special environments (e.g., traffic noise and complex work environments), auditory-tactile integration is crucial for human response and decision making. We investigated the influence of attention on the temporal course and spatial distribution of auditory-tactile integration. Methods: Participants received auditory stimuli alone, tactile stimuli alone, and simultaneous auditory and tactile stimuli, which were randomly presented on the left or right side. For each block, participants attended to all stimuli on the designated side and detected uncommon target stimuli while ignoring all stimuli on the other side. Event-related potentials (ERPs) were recorded via 64 scalp electrodes. Integration was quantified by comparing the response to the combined stimulus to the sum of the responses to the auditory and tactile stimuli presented separately. Results: The results demonstrated that compared to the unattended condition, integration occurred earlier and involved more brain regions in the attended condition when the stimulus was presented in the left hemispace. The unattended condition involved a more extensive range of brain regions and occurred earlier than the attended condition when the stimulus was presented in the right hemispace. Conclusions: Attention can modulate auditory-tactile integration and show systematic differences between the left and right hemispaces. These findings contribute to the understanding of the mechanisms of auditory-tactile information processing in the human brain.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2076-342514122024Contributions of the Primary Sensorimotor Cortex and Posterior Parietal Cortex to Motor Learning and Transfer1184ENChenyuWangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityBackground: Transferring learned manipulations to new manipulation tasks has enabled humans to realize thousands of dexterous object manipulations in daily life. Two-digit grasp and three-digit grasp manipulations require different fingertip forces, and our brain can switch grasp types to ensure good performance according to motor memory. We hypothesized that several brain areas contribute to the execution of the new type of motor according to the motor memory. However, the motor memory mechanisms during this transfer period are still unclear. In the present functional magnetic resonance imaging (fMRI) study, we aimed to investigate the cortical mechanisms involved in motor memory during the transfer phase of learned manipulation tasks. Methods: Using a custom-built T-shaped object with an adjustable weight distribution, the participants performed grasp and lift manipulation tasks under different conditions to simulate the learning and transfer phases. The learning phase consisted of four grasp-and-lift repetitions with one motor type, followed by a transfer phase with four repetitions involving different motors (adding or removing a digit). Results: By comparing brain activity in the learning and transfer phases, we identified three regions (the superior frontal gyrus, supramarginal gyrus, and postcentral gyrus) associated with motor memory during the transfer of learned manipulations. Conclusions: Our findings improve the understanding of the role of the posterior parietal cortex in motor memory, highlighting how sensory information from memory and real-time input is integrated to generate novel motor control signals that guide the precise reapplication of control strategies. Furthermore, we believe that these areas contribute to motor learning from motor memory and may serve as key regions of interest for investigating neurodegenerative diseases.No potential conflict of interest relevant to this article was reported.Japan Society of Mechanical EngineersActa Medica Okayama1881-30541912025Development of tool life prediction system for square end-mills based on database of servo motor current valueJAMDSM0001ENHiroyukiKODAMAFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityMakotoSUZUKIGraduate school of Environmental, Life, Natural Science and Technology, Okayama UniversityKazuhitoOHASHIFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityAccurate prediction of tool life is crucial for reducing production costs and enhancing quality in the machining process. However, such predictions often rely on empirical knowledge, which may limit inexperienced engineers to reliably obtain accurate predictions. This study explores a method to predict the tool life of a cutting machine using servo motor current data collected during the initial stages of tool wear, which is a cost-effective approach. The LightGBM model was identified as suitable for predicting tool life from current data, given the challenges associated with predicting from the average variation of current values. By identifying and utilizing the top 50 features from the current data for prediction, the accuracy of tool life prediction in the early wear stage improved. As this prediction method was developed based on current data obtained during the very early wear stage in experiments with square end-mills, it was tested on extrapolated data using different end-mill diameters. The findings revealed average accuracy rates of 71.2% and 69.4% when using maximum machining time and maximum removal volume as thresholds, respectively.No potential conflict of interest relevant to this article was reported.AIP PublishingActa Medica Okayama0021-9606159192023Efficiency and energy balance for substitution of CH4 in clathrate hydrates with CO2 under multiple-phase coexisting conditions194504ENHidekiTanakaResearch Institute for Interdisciplinary Science, Okayama UniversityMasakazuMatsumotoResearch Institute for Interdisciplinary Science, Okayama UniversityTakumaYagasakiDivision of Chemical Engineering, Graduate School of Engineering Science, Osaka UniversityMany experimental and theoretical studies on CH4–CO2 hydrates have been performed aiming at the extraction of CH4 as a relatively clean energy resource and concurrent sequestration of CO2. However, vague or insufficient characterization of the environmental conditions prevents us from a comprehensive understanding of even equilibrium properties of CH4–CO2 hydrates for this substitution. We propose possible reaction schemes for the substitution, paying special attention to the coexisting phases, the aqueous and/or the fluid, where CO2 is supplied from and CH4 is transferred to. We address the two schemes for the substitution operating in three-phase and two-phase coexistence. Advantages and efficiencies of extracting CH4 in the individual scheme are estimated from the chemical potentials of all the components in all the phases involved in the substitution on the basis of a statistical mechanical theory developed recently. It is found that although substitution is feasible in the three-phase coexistence, its working window in temperature–pressure space is much narrower compared to the two-phase coexistence condition. Despite that the substitution normally generates only a small amount of heat, a large endothermic substitution is suggested in the medium pressure range, caused by the vaporization of liquid CO2 due to mixing with a small amount of the released CH4. This study provides the first theoretical framework toward the practical use of hydrates replacing CH4 with CO2 and serves as a basis for quantitative planning.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama1661-659625222024Distribution and Incorporation of Extracellular Vesicles into Chondrocytes and Synoviocytes11942ENTakashiOhtsukiDepartment of Medical Technology, Graduate School of Health Sciences, Okayama UniversityIkumiSatoDepartment of Medical Technology, Graduate School of Health Sciences, Okayama UniversityRenTakashitaDepartment of Medical Technology, Graduate School of Health Sciences, Okayama UniversityShintaroKodamaDepartment of Medical Technology, Graduate School of Health Sciences, Okayama UniversityKentaroIkemuraDepartment of Medical Technology, Graduate School of Health Sciences, Okayama UniversityGabrielOpokuDepartment of Medical Technology, Graduate School of Health Sciences, Okayama UniversityShogoWatanabeDepartment of Medical Technology, Graduate School of Health Sciences, Okayama UniversityTakayukiFurumatsuDepartment of Orthopedic Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineHiroshiYamadaDepartment of Neuroscience, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineMitsuruAndoLaboratory of Biomaterials, Institute for Life and Medical Sciences, Kyoto UniversityKazunariAkiyoshiDepartment of Immunology, Graduate School of Medicine, Kyoto UniversityKeiichiroNishidaDepartment of Orthopedic Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineSatoshiHirohataDepartment of Medical Technology, Graduate School of Health Sciences, Okayama UniversityOsteoarthritis (OA) is a chronic disease affecting over 500 million people worldwide. As the population ages and obesity rates rise, the societal burden of OA is increasing. Pro-inflammatory cytokines, particularly interleukin-1β, are implicated in the pathogenesis of OA. Recent studies suggest that crosstalk between cartilage and synovium contributes to OA development, but the mechanisms remain unclear. Extracellular vesicles (EVs) were purified from cell culture-conditioned medium via ultracentrifugation and confirmed using transmission electron microscopy, nanoparticle tracking analysis, and western blotting. We demonstrated that EVs were taken up by human synoviocytes and chondrocytes in vitro, while in vivo experiments revealed that fluorescent-labelled EVs injected into mouse joints were incorporated into chondrocytes and synoviocytes. EV uptake was significantly inhibited by dynamin-mediated endocytosis inhibitors, indicating that endocytosis plays a major role in this process. Additionally, co-culture experiments with HEK-293 cells expressing red fluorescent protein (RFP)-tagged CD9 and the chondrocytic cell line OUMS-27 confirmed the transfer of RFP-positive EVs across a 600-nm but not a 30-nm filter. These findings suggest that EVs from chondrocytes are released into joint fluid and taken up by cells within the cartilage, potentially facilitating communication between cartilage and synovium. The results underscore the importance of EVs in OA pathophysiology.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0305-05481692024The parallel stack loading problem of minimizing the exact number of relocations106712ENShunjiTanakaFaculty of Environmental, Life and Natural Science and Technology, Okayama UniversityMohamedElWakilDepartment of Production Engineering and Mechanical Design, Faculty of Engineering, Tanta UniversityAmrEltawilDepartment of Industrial and Manufacturing Engineering, Egypt Japan University of Science and TechnologyThis study addresses the parallel stack loading problem, a general optimization problem arising in storage facilities such as container yards, slab yards, and warehouses. In this problem, we load incoming items into parallel stacks in the loading phase to minimize the number of relocations in the subsequent retrieval phase. Because of difficulties in treating the nested problem structure originating from the mutual dependence of the two phases, the existing studies approximately minimized the number of relocations using surrogate objective functions. In contrast, this study considers the parallel stack loading problem aiming to minimize the exact number of relocations. We first provide an integer programming formulation and next develop a nested branch-and-bound algorithm. In a computational study, we verify the effectiveness of the proposed branch-and-bound algorithm and evaluate the known surrogate objective functions based on the exact minimization.No potential conflict of interest relevant to this article was reported.岡山大学経済学会Acta Medica Okayama2433-41465622024なぜ中間組織が必要なのか116ENDaijiFujiiTamakoOshima/10.18926/OER/67705 This paper challenges a fundamental question, ‘Why is an intermediate organization necessary?’ Due to transaction costs and market failures on the one hand and the limitations of organizational control mechanisms on the other hand, many‘ intermediate organizations’ are observed in the real world. How can we tackle to explain the governance mechanism considered to be‘ intermediate?’
If we are to discuss such socioeconomic orders, this paper assumes that we should not be able to link micro-level explanations and macro-level ones concerning the third mode of governance mechanisms all at once. We need to stick to the meso-level at fi rst. The theoretical elaboration since Ouchi’s（1980） discussion of clan-type governance and cumulative empirical research on industrial agglomerations have allowed us to construct a more sophisticated theory called community capital.
In effective communities, members are ‘embedded as insiders’ who serve the purpose of the community, share experiences of failures and successes, and find and deepen their common identity. This limited membership is bound by‘ mutual trust to rely on each other’ for‘ distribution of short-term risks.’ In contrast to social norms that need to be abstract enough to be widely shared, the communal norms that are concrete enough to allow the members to understand without hesitation how they should behave in localized contexts are cumulatively cultivated along socializing process. Among the norms, sense of mutual obligation to incur intermittent costs for the whole community is a crucial norm for the sustainable development of the community. However, as a practical matter, membership control, mutual trust and short-term risk allocation may serve the communities in the short run, but they do not guarantee long-term accumulation of shared capital. As a result, the limits of community capital may need to be discussed once again, especially today when market liquidity is increasing, and its failures tend to become more apparent in a variety of areas.No potential conflict of interest relevant to this article was reported.Royal Society of ChemistryActa Medica Okayama2633-54095222024Enhanced piezo-response of mixed-cation copper perovskites with Cl/Br halide engineering89538960ENAmrElattarGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityChristopherMunozIndustrial & Manufacturing Engineering, FAMU-FSU College of EngineeringLiborKoberaInstitute of Macromolecular Chemistry of the Czech Academy of SciencesAndriiMahunInstitute of Macromolecular Chemistry of the Czech Academy of SciencesJiriBrusInstitute of Macromolecular Chemistry of the Czech Academy of SciencesMohammed JasimUddinPhotonics and Energy Research Laboratory (PERL), Department of Mechanical Engineering, The University of TexasYasuhikoHayashiGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityOkenwaOkoliIndustrial & Manufacturing Engineering, FAMU-FSU College of EngineeringTarikDickensIndustrial & Manufacturing Engineering, FAMU-FSU College of EngineeringHalide and cation engineering of organic-inorganic hybrid perovskites has shown a great potential for structural modulation of perovskites and enhancing their optoelectronic properties. Here, we studied the impact of Cl/Br halide engineering on the structural and piezoelectric properties of MA/Cs mixed-cation Cu-perovskite crystals. X-ray diffraction, Raman spectroscopy, and 133Cs solid-state NMR were utilized to find out the nature of the perovskite crystal structure formation. Three distinct crystal structures were obtained depending on the Cl/Br content. High Cl content resulted in the formation of Br-doped (Cs/MA)CuCl3 perovskite with the presence of paramagnetic Cu2+ ions. High Br content led to the formation of Cl-doped (MA/Cs)2CuBr4 perovskite with the presence of diamagnetic Cu+ ions. Equimolar Cl/Br perovskite content gave a novel crystal structure with the formation of well-dispersed diamagnetic domains. Compared to the high Cl/Br containing perovskites, the equimolar Cl/Br perovskite revealed the highest potential for piezoelectric applications with a maximum recordable piezoelectric output voltage of 5.0 V. The results provide an insight into the importance of mixed-halide and mixed-cation engineering for tailoring the perovskite structural properties towards a wide range of efficient optoelectronics.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X7852024Effect of Radon Inhalation on Murine Brain Proteins: Investigation Using Proteomic and Multivariate Analyses387399ENShotaNaoeGraduate School of Health Sciences, Okayama UniversityAyumiTanakaGraduate School of Health Sciences, Okayama UniversityNorieKanzakiNingyo-toge Environmental Engineering Center, Japan Atomic Energy AgencyReijuTakenakaGraduate School of Health Sciences, Okayama UniversityAkihiroSakodaNingyo-toge Environmental Engineering Center, Japan Atomic Energy AgencyTakaakiMiyajiAdvanced Science Research Center, Okayama UniversityKiyonoriYamaokaFaculty of Health Sciences, Okayama UniversityTakahiroKataokaFaculty of Health Sciences, Okayama UniversityOriginal Article/10.18926/AMO/67663Radon is a known risk factor for lung cancer; however, it can be used beneficially, such as in radon therapy. We have previously reported the enhancement of antioxidant effects associated with trace amounts of oxidative stress as one of the positive biological effects of radon inhalation. However, the biological effects of radon inhalation are incompletely understood, and more detailed and comprehensive studies are required. Although several studies have used proteomics to investigate the effects of radon inhalation on body proteins, none has focused on brain proteins. In this study, we evaluated the expression status of proteins in murine brains using proteomic and multivariate analyses to identify those whose expressions changed following two days of radon inhalation at a concentration of 1,500 Bq/m3. We found associations of radon inhalation with the expressions of seven proteins related to neurotransmission and heat shock. These proteins may be proposed as biomarkers indicative of radon inhalation. Although further studies are required to obtain the detailed biological significance of these protein alterations, this study contributes to the elucidation of the biological effects of radon
inhalation as a low-dose radiation.No potential conflict of interest relevant to this article was reported.Royal Society of ChemistryActa Medica Okayama2046-206914322024Lead-free iron-doped Cs3Bi2Br9 perovskite with tunable properties2317723183ENThiriHtunGraduate School of Natural Science and Technology, Okayama UniversityAmrElattarDepartment of Chemistry, Faculty of Science, Ain Shams UniversityHythamElbohyPhysics Department, Faculty of Science, Damietta UniversityKoseiTsutsumiGraduate School of Natural Science and Technology, Okayama UniversityKazumasaHoriganeResearch Institute for Interdisciplinary Science, Okayama UniversityChiyuNakanoAdvanced Science Research Center, Okayama UniversityXiaoyuGuGuangdong University Key Laboratory for Advanced Quantum Dot Displays and Lighting and Department of Electronic & Electrical Engineering, Southern University of Science and TechnologyHirooSuzukiGraduate School of Natural Science and Technology, Okayama UniversityTakeshiNishikawaGraduate School of Natural Science and Technology, Okayama UniversityAung Ko KoKyawGuangdong University Key Laboratory for Advanced Quantum Dot Displays and Lighting and Department of Electronic & Electrical Engineering, Southern University of Science and TechnologyYasuhikoHayashiGraduate School of Natural Science and Technology, Okayama UniversityPerovskite based on cesium bismuth bromide offers a compelling, non-toxic alternative to lead-containing counterparts in optoelectronic applications. However, its widespread usage is hindered by its wide bandgap. This study investigates a significant bandgap tunability achieved by introducing Fe doping into the inorganic, lead-free, non-toxic, and stable Cs3Bi2Br9 perovskite at varying concentrations. The materials were synthesized using a facile method, with the aim of tuning the optoelectronic properties of the perovskite materials. Characterization through techniques such as X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, energy dispersive spectroscopy (EDS), and UV-vis spectroscopy was conducted to elucidate the transformation mechanism of the doping materials. The substitution process results in a significant change in the bandgap energy, transforming from the pristine Cs3Bi2Br9 with a bandgap of 2.54 eV to 1.78 eV upon 70% Fe doping. The addition of 50% Fe in Cs3Bi2Br9 leads to the formation of the orthorhombic structure in Cs2(Bi,Fe)Br5 perovskite, while complete Fe alloying at 100% results in the phase formation of CsFeBr4 perovskite. Our findings on regulation of bandgap energy and crystal structure through B site substitution hold significant promise for applications in optoelectronics.No potential conflict of interest relevant to this article was reported.Japan Society of Mechanical EngineersActa Medica Okayama2187-97451162024Effect of artificial defect on tensile properties of thin titanium alloy wire24-00129ENJunjiSAKAMOTOOkayama UniversityNaoyaTADAOkayama UniversityTakeshiUEMORIOkayama UniversityKoyoOISHIOkayama UniversityThis study investigated the effects of artificial defects, introduced via focused ion beam (FIB) processing, on the tensile properties of thin titanium alloy wires (Ti-6Al-4V). Results indicated that the defective wires fractured when the net-section nominal stress reached the ultimate tensile strength of the smooth wires, probably because of localized stress concentrations relaxing due to plastic deformation around the defects. The effect of defects on tensile properties was classified into three regions based on the size of the defect area. In the case of small defects, wires fractured at the smooth area away from the defects where the cross-sectional strength was lower. In this case, the defects minimally affected the tensile properties. This is attributable to variations in the cross-sectional strength of the wire, which resulted in some sections with lower strength as compared with the defect area. In the case of medium-sized defects, the fracture strain decreased gradually as the defect area increased. Finally, in the case of large defects, the fracture strain was extremely small. The boundary between the medium-sized and large defects indicates the transition from plastic deformation to no plastic deformation in the smooth area.No potential conflict of interest relevant to this article was reported.ElsevierActa Medica Okayama2590-1230232024Crystal plasticity analysis of fatigue crack initiation site considering crystallographic orientation in Ti-22V-4Al alloy102405ENJintaArakawaGraduate School of Natural Science and Technology, Okayama UniversityKokiHirazumiGraduate School of Natural Science and Technology, Okayama UniversityTakeshiUemoriGraduate School of Natural Science and Technology, Okayama UniversityYoshitoTakemotoGraduate School of Natural Science and Technology, Okayama UniversityIn this study, plane bending fatigue tests were conducted on Ti-22V-4Al alloy, a beta-type titanium alloy, to examine the fatigue crack initiation behavior in detail. In addition, the prediction of fatigue crack initiation points was investigated from the perspectives of the Schmidt factor (SF) and crystal plasticity finite element method (CP-FEM). The slip system contributing to fatigue crack initiation can be accurately predicted by assessing the magnitude relationship of SF. Also, this prediction is already indicated in a lot of paper by using out of component of slip activity. However, the location where the fatigue crack will occur can be not estimated by SF on polycrystalline. Therefore, prediction of grains where fatigue cracks will occur could be achieved with high accuracy by constructing a CP-FEM that considers the mechanical interaction of polycrystals and grain boundary. Utilizing advanced methodologies such as CP-FEM and numerical calculation techniques, it is strictly investigated that the factors influencing fatigue crack initiation in polycrystalline materials. Our research concluded the understanding of fatigue crack initiation on polycrystal grains by considering the mechanical interaction of polycrystals and grain boundary.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2076-34251452024Go/No-Go Ratios Modulate Inhibition-Related Brain Activity: An Event-Related Potential Study414ENNanZhangGraduate of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityWeichaoAnGraduate of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYinghuaYuGraduate of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJinglongWuGraduate of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiajiaYangGraduate of Interdisciplinary Science and Engineering in Health Systems, Okayama University(1) Background: Response inhibition refers to the conscious ability to suppress behavioral responses, which is crucial for effective cognitive control. Currently, research on response inhibition remains controversial, and the neurobiological mechanisms associated with response inhibition are still being explored. The Go/No-Go task is a widely used paradigm that can be used to effectively assess response inhibition capability. While many studies have utilized equal numbers of Go and No-Go trials, how different ratios affect response inhibition remains unknown; (2) Methods: This study investigated the impact of different ratios of Go and No-Go conditions on response inhibition using the Go/No-Go task combined with event-related potential (ERP) techniques; (3) Results: The results showed that as the proportion of Go trials decreased, behavioral performance in Go trials significantly improved in terms of response time, while error rates in No-Go trials gradually decreased. Additionally, the NoGo-P3 component at the central average electrodes (Cz, C1, C2, FCz, FC1, FC2, PCz, PC1, and PC2) exhibited reduced amplitude and latency; (4) Conclusions: These findings indicate that different ratios in Go/No-Go tasks influence response inhibition, with the brain adjusting processing capabilities and rates for response inhibition. This effect may be related to the brain's predictive mechanism model.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2075-163X1452024Measurements of Thermodynamic Data of Water in Ca-Bentonite by Relative Humidity Method477ENKosukeIchikawaGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityHaruoSatoGraduate School of Environmental, Life, Natural Science and Technology, Okayama UniversityBuffer material (compacted bentonite), one of the engineered barrier elements in the geological disposal of a high-level radioactive waste, develops swelling stress due to groundwater penetration from the surrounding rock mass. Montmorillonite is the major clay mineral component of bentonite. Even previous studies provide few mechanical and thermodynamic data on Ca-montmorillonite. In this study, thermodynamic data on Ca-montmorillonite were obtained as a function of water content by measuring relative humidity (RH) and temperature. The activities of water and the relative partial molar Gibbs free energies of water were determined from the experimental results, and the swelling stress of Ca-bentonite was calculated using the thermodynamic model and compared with measured data. The activities of water and the relative partial molar Gibbs free energies obtained in the experiments decreased with decreasing water content in water contents lower than about 25%. This trend was similar to that of Na-montmorillonite. The swelling stress calculated based on the thermodynamic model was approximately 200 MPa at a montmorillonite partial density of 2.0 Mg/m3 and approximately 10 MPa at a montmorillonite partial density of 1.4 Mg/m3. The swelling stresses in the high-density region (around 2.0 Mg/m3) were higher than that of Na-montmorillonite and were similar levels in the low-density region (around 1.5 Mg/m3). Comparison with measured data showed the practicality of the thermodynamic model.No potential conflict of interest relevant to this article was reported.IOP PublishingActa Medica Okayama1882-07781692023Active control of localized mode and transmission in topological phononic waveguides by non-Hermitian modulation094001ENMd. ShuzonAliDepartment of Electrical and Electronic Engineering, Okayama UniversityYusukeHataDepartment of Electrical and Electronic Engineering, Okayama UniversityKenjiTsurutaDepartment of Electrical and Electronic Engineering, Okayama UniversityWe demonstrate the switching behavioral differences between lossy and nearly lossless edge-mode propagation by non-Hermitian modulation based on the phononic band design of a C3v symmetric, two-dimensional phononic crystal with a unit cell composed of three air-filled circular holes in polydimethylsiloxane. We numerically show that strong loss effects lead to the extinction of the localized modes. This mechanism is analogous to the bound-to-unbound transition in non-Hermitian quantum systems. This result suggests that large variations in non-Hermitian modulation can be used for the active control of edge-mode propagation along topological interfaces.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama0946-271610142023Novel extracellular role of REIC/Dkk-3 protein in PD-L1 regulation in cancer cells431447ENYumaGoharaDepartment of Cell Biology, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineNahokoTomonobuDepartment of Cell Biology, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineRieKinoshitaDepartment of Cell Biology, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineJunichiroFutamiDepartment of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityLénaAudebertDepartment of Cell Biology, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineYouyiChenDepartment of Cell Biology, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineNi Luh Gede YoniKomalasariDepartment of Cell Biology, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineFanJiangDepartment of Cell Biology, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineChikakoYoshizawaDepartment of Cell Biology, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineHitoshiMurataDepartment of Cell Biology, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineKen-ichiYamamotoDepartment of Cell Biology, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineMasamiWatanabeDepartment of Urology, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineHiromiKumonInnovation Center Okayama for Nanobio-Targeted Therapy, Okayama UniversityMasakiyoSakaguchiDepartment of Cell Biology, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of MedicineThe adenovirus-REIC/Dkk-3 expression vector (Ad-REIC) has been the focus of numerous clinical studies due to its potential for the quenching of cancers. The cancer-suppressing mechanisms of the REIC/DKK-3 gene depend on multiple pathways that exert both direct and indirect effects on cancers. The direct effect is triggered by REIC/Dkk-3-mediated ER stress that causes cancer-selective apoptosis, and the indirect effect can be classified in two ways: (i) induction, by Ad-REIC-mis-infected cancer-associated fibroblasts, of the production of IL-7, an important activator of T cells and NK cells, and (ii) promotion, by the secretory REIC/Dkk-3 protein, of dendritic cell polarization from monocytes. These unique features allow Ad-REIC to exert effective and selective cancer-preventative effects in the manner of an anticancer vaccine. However, the question of how the REIC/Dkk-3 protein leverages anticancer immunity has remained to be answered. We herein report a novel function of the extracellular REIC/Dkk-3—namely, regulation of an immune checkpoint via modulation of PD-L1 on the cancer-cell surface. First, we identified novel interactions of REIC/Dkk-3 with the membrane proteins C5aR, CXCR2, CXCR6, and CMTM6. These proteins all functioned to stabilize PD-L1 on the cell surface. Due to the dominant expression of CMTM6 among the proteins in cancer cells, we next focused on CMTM6 and observed that REIC/Dkk-3 competed with CMTM6 for PD-L1, thereby liberating PD-L1 from its complexation with CMTM6. The released PD-L1 immediately underwent endocytosis-mediated degradation. These results will enhance our understanding of not only the physiological nature of the extracellular REIC/Dkk-3 protein but also the Ad-REIC-mediated anticancer effects.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X7822024p53-Armed Oncolytic Virotherapy Improves Radiosensitivity in Soft-Tissue Sarcoma by Suppressing BCL-xL Expression151161ENTadashiKomatsubaraDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesHiroshiTazawaDepartment of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesJoeHaseiDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesToshinoriOmoriDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesKazuhisaSugiuDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesYusukeMochizukiDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesKojiDemiyaDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesAkiYoshidaDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesTomohiroFujiwaraDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesToshiyukiKunisadaDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesYasuoUrataOncolys BioPharma, Inc.ShunsukeKagawaDepartment of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesToshifumiOzakiDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesToshiyoshiFujiwaraDepartment of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesOriginal Article/10.18926/AMO/66924Soft-tissue sarcoma (STS) is a heterogeneous group of rare tumors originating predominantly from the embryonic mesoderm. Despite the development of combined modalities including radiotherapy, STSs are often refractory to antitumor modalities, and novel strategies that improve the prognosis of STS patients are needed. We previously demonstrated the therapeutic potential of two telomerase-specific replication-competent oncolytic adenoviruses, OBP-301 and tumor suppressor p53-armed OBP-702, in human STS cells. Here, we demonstrate in vitro and in vivo antitumor effects of OBP-702 in combination with ionizing radiation against human STS cells (HT1080, NMS-2, SYO-1). OBP-702 synergistically promoted the antitumor effect of ionizing radiation in the STS cells by suppressing the expression of B-cell lymphoma-X large (BCL-xL) and enhancing ionizing radiation-induced apoptosis. The in vivo experiments demonstrated that this combination therapy significantly suppressed STS tumors’ growth. Our results suggest that OBP-702 is a promising antitumor reagent for promoting the radiosensitivity of STS tumors.No potential conflict of interest relevant to this article was reported.Oxford University Press (OUP)Acta Medica Okayama0032-078164112023Transcriptomic Interpretation on Explainable AI-Guided Intuition Uncovers Premonitory Reactions of Disordering Fate in Persimmon Fruit13231330ENKanaeMasudaGraduate School of Environmental and Life Science, Okayama UniversityErikoKuwadaGraduate School of Environmental and Life Science, Okayama UniversityMariaSuzukiGraduate School of Environmental and Life Science, Okayama UniversityTetsuyaSuzukiGifu Prefectural Agricultural Technology CenterTakeshiNiikawaGifu Prefectural Agricultural Technology CenterSeiichiUchidaFaculty of Information Science and Electrical Engineering, Kyusyu UniversityTakashiAkagiGraduate School of Environmental and Life Science, Okayama UniversityDeep neural network (DNN) techniques, as an advanced machine learning framework, have allowed various image diagnoses in plants, which often achieve better prediction performance than human experts in each specific field. Notwithstanding, in plant biology, the application of DNNs is still mostly limited to rapid and effective phenotyping. The recent development of explainable CNN frameworks has allowed visualization of the features in the prediction by a convolutional neural network (CNN), which potentially contributes to the understanding of physiological mechanisms in objective phenotypes. In this study, we propose an integration of explainable CNN and transcriptomic approach to make a physiological interpretation of a fruit internal disorder in persimmon, rapid over-softening. We constructed CNN models to accurately predict the fate to be rapid softening in persimmon cv. Soshu, only with photo images. The explainable CNNs, such as Gradient-weighted Class Activation Mapping (Grad-Class Activation Mapping (CAM)) and guided Grad-CAM, visualized specific featured regions relevant to the prediction of rapid softening, which would correspond to the premonitory symptoms in a fruit. Transcriptomic analyses to compare the featured regions of the predicted rapid-softening and control fruits suggested that rapid softening is triggered by precocious ethylene signal–dependent cell wall modification, despite exhibiting no direct phenotypic changes. Further transcriptomic comparison between the featured and non-featured regions in the predicted rapid-softening fruit suggested that premonitory symptoms reflected hypoxia and the related stress signals finally to induce ethylene signals. These results would provide a good example for the collaboration of image analysis and omics approaches in plant physiology, which uncovered a novel aspect of fruit premonitory reactions in the rapid-softening fate.No potential conflict of interest relevant to this article was reported.The Japan Society of Mechanical Engineers and The Heat Transfer Society of JapanActa Medica Okayama1880-55661912024Radiative energy transfer via surface plasmon polaritons around metal–insulator grating: For better understanding of magnetic polariton23-00531ENKazumaISOBEDepartment of Advanced Mechanics, Graduate School of Natural Science and Technology, Okayama UniversityYutakaYAMADADepartment of Advanced Mechanics, Graduate School of Natural Science and Technology, Okayama UniversityAkihikoHORIBEDepartment of Advanced Mechanics, Graduate School of Natural Science and Technology, Okayama UniversityKatsunoriHANAMURASchool of Engineering, Department of Mechanical Engineering, Tokyo Institute of TechnologyA conventional metal–insulator nanograting has the potential to transmit near-infrared thermal radiation because an electromagnetic wave is resonated in the grating structure. Surface plasmon polaritons (SPPs) take place at the interface between the metal and the insulator with boundaries at both ends. Physicists formulated the resonance frequency of the grating from the Fabry–Pérot interference between the grating thickness and the wavelength of SPPs in a short-range coupled mode. On the other hand, engineering researchers often use a lumped-element model assuming a resonant circuit consisting of an inductance of metal and a capacitance of metal-insulator-metal grating structure. Furthermore, they have considered that the resonant circuit excites a strong magnetic field independent of SPPs. This study compares each physical model and numerical simulation results, then clearly shows that all resonance frequencies and features of the circuit resonance can be described by the Fabry–Pérot interference of the SPPs in short-range coupled mode. Moreover, the estimated resonance frequencies obviously correspond to the local maxima of the transmittance of the nanograting with the various thicknesses and pitches. In this case, a strong magnetic field can be observed in the insulator layer as if it might be an isolated magnetic quantum. However, since materials show no magnetism at near-infrared frequencies, the magnetic response appears due to the contribution of SPPs.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2076-26151422024A System for Monitoring Animals Based on Behavioral Information and Internal State Information281ENTaroShibanokiDepartment of Intelligent Mechanical Systems, Faculty of Environmental, Life, Natural Science and Technology, Okayama UniversityYuugoYamazakiMajor in Computer and Information Sciences, Graduate School of Science and Engineering, Ibaraki UniversityHideyukiTonookaMajor in Computer and Information Sciences, Graduate School of Science and Engineering, Ibaraki UniversityManaging the risk of injury or illness is an important consideration when keeping pets. This risk can be minimized if pets are monitored on a regular basis, but this can be difficult and time-consuming. However, because only the external behavior of the animal can be observed and the internal condition cannot be assessed, the animal’s state can easily be misjudged. Additionally, although some systems use heartbeat measurement to determine a state of tension, or use rest to assess the internal state, because an increase in heart rate can also occur as a result of exercise, it is desirable to use this measurement in combination with behavioral information. In the current study, we proposed a monitoring system for animals using video image analysis. The proposed system first extracts features related to behavioral information and the animal’s internal state via mask R-CNN using video images taken from the top of the cage. These features are used to detect typical daily activities and anomalous activities. This method produces an alert when the hamster behaves in an unusual way. In our experiment, the daily behavior of a hamster was measured and analyzed using the proposed system. The results showed that the features of the hamster’s behavior were successfully detected. When loud sounds were presented from outside the cage, the system was able to discriminate between the behavioral and internal changes of the hamster. In future research, we plan to improve the accuracy of the measurement of small movements and develop a more accurate system.No potential conflict of interest relevant to this article was reported.Royal Society of Chemistry (RSC)Acta Medica Okayama1744-683X2072024Controlled mechanical properties of poly(ionic liquid)-based hydrophobic ion gels by the introduction of alumina nanoparticles with different shapes16111619ENYunaMizutaniDepartment of Applied Chemistry, Graduate School of Natural Science, Okayama UniversityTakaichiWatanabeDepartment of Applied Chemistry, Graduate School of Natural Science, Okayama UniversityCarlos G.LopezDepartment of Materials Science and Engineering, The Pennsylvania State UniversityTsutomuOnoDepartment of Applied Chemistry, Graduate School of Natural Science, Okayama UniversityIonic–liquid gels, also known as ion gels, have gained considerable attention due to their high ionic conductivity and CO2 absorption capacity. However, their low mechanical strength has hindered their practical applications. A potential solution to this challenge is the incorporation of particles, such as silica nanoparticles, TiO2 nanoparticles, and metal–organic frameworks (MOFs) into ion gels. Comparative studies on the effect of particles with different shapes are still in progress. This study investigated the effect of the shape of particles introduced into ion gels on their mechanical properties. Consequently, alumina/poly(ionic liquid) (PIL) double-network (DN) ion gels consisting of clustered alumina nanoparticles with various shapes (either spherical or rod-shaped) and a chemically crosslinked poly[1-ethyl-3-vinylimidazolium bis(trifluoromethanesulfonyl)imide] (PC2im-TFSI, PIL) network were prepared. The results revealed that the mechanical strengths of the alumina/PIL DN ion gels were superior to those of PIL single-network ion gels without particles. Notably, the fracture energies of the rod-shaped alumina/PIL DN ion gels were approximately 2.6 times higher than those of the spherical alumina/PIL DN ion gels. Cyclic tensile tests were performed, and the results indicate that the loading energy on the ion gel was dissipated through the fracture of the alumina network. TEM observation suggests that the variation in the mechanical strength depending on the shape can be attributed to differences in the aggregation structure of the alumina particles, thus indicating the possibility of tuning the mechanical strength of ion gels by altering not only particle kinds but its shape.No potential conflict of interest relevant to this article was reported.ElsevierActa Medica Okayama1350-63071532023Prediction of slip activity of crystal grains around semi-circular and semi-elliptical notches in thin-sheet specimens of pure titanium using formulated macroscopic stress distribution and crystal orientation107623ENNaoyaTadaFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityTakeshiUemoriFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityJunjiSakamotoFaculty of Environmental, Life, Natural Science and Technology, Okayama UniversityThin metal sheets and wires are important materials for various devices used in electrical, mechanical, and medical fields. With the downsizing of these devices, demand for thinner sheets and wires has increased. Amongst the many metals available, pure titanium has been attracting much attention for use in medical and dental devices because of its good biocompatibility in addition to its light weight and high corrosion resistance. However, thin metal sheets and wires are usually polycrystalline materials and, with the downsizing of materials, there is a loss of homogeneity during deformations. Inhomogeneous deformation becomes significant in thin sheets and wires, owing to the different crystal orientations and geometries of crystal grains. Furthermore, the shapes of such devices are not uniform, unlike, say, a simple rod. Therefore, macroscopic stress and strain concentrations should be taken into consideration when designing these devices as they affect the localization of deformation and the resultant fracture. In this study, semi-circular and semi-elliptical notched specimens made of thin-sheet polycrystalline pure titanium are subjected to tensile testing. Inhomogeneous deformation caused by crystallographic slip is observed near the notch root. Analysis of the crystal orientation and observation of the slip line show that the slip initiation in crystal grains is affected by the macroscopic stress distribution and can be predicted from the slip activity calculated from both the critical resolved shear stress on the slip systems and the resolved shear stress acting on prospective slip planes obtained from the macroscopic multiaxial stress distribution.No potential conflict of interest relevant to this article was reported.American Physiological SocietyActa Medica Okayama0022-307712752022Tactile angle discriminability improvement: contributions of working memory training and continuous attended sensory input13981406ENWuWangSchool of Psychological and Cognitive Sciences, Peking UniversityJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityHuazhiLiGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYulongLiuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYiyangYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiabinYuCollege of Information Engineering, China Jiliang UniversityXiaoyuTangSchool of Psychology, Liaoning Collaborative Innovation Center of Children and Adolescents Healthy Personality Assessment and Cultivation, Liaoning Normal UniversityJingjingYangSchool of Computer Science and Technology, Changchun University of Science and TechnologySatoshiTakahashiGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYoshimichiEjimaGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJinglongWuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityPerceptual learning is commonly assumed to enhance perception through continuous attended sensory input. However, learning is generalizable to performance in untrained stimuli and tasks. Although previous studies have observed a possible generalization effect across tasks as a result of working memory (WM) training, comparisons of the contributions of WM training and continuous attended sensory input to perceptual learning generalization are still rare. Therefore, we compared which factors contributed most to perceptual generalization and investigated which skills acquired during WM training led to tactile generalization across tasks. Here, a Braille-like dot pattern matching n-back WM task was used as the WM training task, with four workload levels (0, 1, 2, and 3-back levels). A tactile angle discrimination (TAD) task was used as a pre- and posttest to assess improvements in tactile perception. Between tests, four subject groups were randomly assigned to four different workload n-back tasks to consecutively complete three sessions of training. The results showed that tactile n-back WM training could enhance TAD performance, with the 3-back training group having the highest TAD threshold improvement rate. Furthermore, the rate of WM capacity improvement on the 3-back level across training sessions was correlated with the rate of TAD threshold improvement. These findings suggest that continuous attended sensory input and enhanced WM capacity can lead to improvements in TAD ability, and that greater improvements in WM capacity can predict greater improvements in TAD performance.<br>
NEW & NOTEWORTHY Perceptual learning is not always specific to the trained task and stimuli. We demonstrate that both continuous attended sensory input and improved WM capacity can be used to enhance tactile angle discrimination (TAD) ability. Moreover, WM capacity improvement is important in generalizing the training effect to the TAD ability. These findings contribute to understanding the mechanism of perceptual learning generalization across tasks.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0006-3495121172022High hydrostatic pressure induces slow contraction in mouse cardiomyocytes32863294ENYoheiYamaguchiDepartment of Cardiovascular Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityMasayoshiNishiyamaDepartment of Physics, Faculty of Science and Engineering, Kindai UniversityHiroakiKaiDepartment of Cardiovascular Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityToshiyukiKanekoDepartment of Physiology, Asahikawa Medical UniversityKeikoKaiharaDepartment of Cardiovascular Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityGentaroIribeDepartment of Cardiovascular Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityAkiraTakaiDepartment of Physiology, Asahikawa Medical UniversityKeijiNaruseDepartment of Cardiovascular Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityMasatoshiMorimatsuDepartment of Cardiovascular Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityCardiomyocytes are contractile cells that regulate heart contraction. Ca2+ flux via Ca2+ channels activates actomyosin interactions, leading to cardiomyocyte contraction, which is modulated by physical factors (e.g., stretch, shear stress, and hydrostatic pressure). We evaluated the mechanism triggering slow contractions using a high-pressure microscope to characterize changes in cell morphology and intracellular Ca2+ concentration ([Ca2+]i) in mouse cardiomyocytes exposed to high hydrostatic pressures. We found that cardiomyocytes contracted slowly without an acute transient increase in [Ca2+]i, while a myosin ATPase inhibitor interrupted pressure-induced slow contractions. Furthermore, transmission electron microscopy showed that, although the sarcomere length was shortened upon the application of 20 MPa, this pressure did not collapse cellular structures such as the sarcolemma and sarcomeres. Our results suggest that pressure-induced slow contractions in cardiomyocytes are driven by the activation of actomyosin interactions without an acute transient increase in [Ca2+]i.No potential conflict of interest relevant to this article was reported.岡山大学経済学会Acta Medica Okayama2433-41465522023地方公共サービス革新プロセスの視座の構築114ENDaijiFujiiHiroshiKanaji10.18926/OER/66033 When local governments develop public services, they often experience innovation processes. More often, the innovation processes referred to here seem to be the perceived needs for transformation faced with external pressures and the purposive responses to them. This article tries to depict this discourse from a different viewpoint. One of the perspectives that has been proposed so far is that the external environments are made up of multiple actors, and that the historical backgrounds and the relationships between these actors affect the structure of administrative organizations and the methods of providing public services. The transformation processes could be one-time events no matter how long the processes may take, but this article tries to argue they may connote a circular mechanism where both of the administrative organizations and the external actors feedback to each other. In order to elaborate this direction of theorizing, three steps are employed by applying existent literature of various types developed in rather a broader context of social sciences. First, if one of the goals of postmodern theorization is liberating the psychological energies of actors from the cramped social reality that structuralists postulated, then Actor-Network-Theory may be useful. Second, according to Sarasbathy’s research on entrepreneurial behaviors, the view that we effectuate our future through what we can do now is attractive in order to create a new discourse of social innovations, where we appreciate them as not springing out of nowhere all of sudden. Third, once this article accepts polyphonic views on social realities where congested discourses interact during abovementioned process, the role of civic entrepreneurs on the frontline can never be overstated enough. This is because such civic entrepreneurs could cooperate with minority opinions and raise them into broader contexts of dialogues within societies.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2073-443314102023Numerical Analysis of Various Heat Countermeasures: Effects on Energy Consumption and Indoor Thermal Comfort in Densely Built Wooden House Area1566ENShanshanLiuDepartment of Architecture and Building Engineering, Tokyo Institute of TechnologyRonnenLevinsonHeat Island Group, Lawrence Berkeley National LaboratoryDaisukeNarumiGraduate School of Environmental and Life Science, Okayama UniversityDensely built areas with poor thermal insulation suffer from high thermal environmental risks and generally consume high energy in summer. Determining the relationship between density and energy consumption is necessary, particularly when implementing urban heat island (UHI) countermeasures. This study evaluated the effects of density and UHI countermeasures on the energy consumption and indoor thermal comfort of a detached house in a typical densely built wooden house area in Yokohama City, Japan. Three densities and six countermeasures were considered. Annual hourly simulations based on the SCIENCE-Vent thermal environment simulation model yielded the following results: in densely built wooden house areas, the energy consumption and thermal discomfort increased with density. The green roof yielded the largest energy savings in the cooling and heating seasons, demonstrating the highest annual energy savings with 5.7%. Density had little impact on rooftop countermeasures, but the effect of the high-reflectance walls increased with density, and the reduction in annual energy consumption (air conditioning and lighting) is 2.6%, 3.0%, 3.6% in 37%, 47%, and 59% density cases, respectively. The impact of thermal countermeasures on indoor thermal comfort varied according to the thermal control mechanism.No potential conflict of interest relevant to this article was reported.Fuji Technology Press Ltd.Acta Medica Okayama1883-80493422022Development of a Spiral Shaped Soft Holding Actuator Using Extension Type Flexible Pneumatic Actuators373381ENSoShimookaGraduate School of Natural Science and Technology, Okayama UniversityTetsuyaAkagiDepartment of Intelligent Mechanical Engineering, Okayama University of ScienceShujiroDohtaDepartment of Intelligent Mechanical Engineering, Okayama University of ScienceTakashiShinoharaDesign and Manufacturing Center, Organization for Research Development and Outreach, Okayama University of ScienceTakumiKobayashiDepartment of Intelligent Mechanical Engineering, Okayama University of ScienceRecently, several pneumatic soft actuators have been applied to wearable and welfare devices to provide nursing care and physical support for the elderly and disabled. In this study, as a wearable soft actuator for holding body, a spiral shaped soft holding actuator that can wrap a user according to their body shape was proposed and tested. The construction and operating principle of the tested soft actuator with circumferential restraint mechanism using three extension type flexible pneumatic actuators (EFPAs) has been discussed. As a result, it was found that the tested actuator could hold elbows and knees when the joint is in motion. An analytical model of the spiral actuator was also proposed to achieve an optimal design. It can be confirmed that the proposed analytical model can predict the shape of the actuator when various EFPAs are pressurized.No potential conflict of interest relevant to this article was reported.American Chemical SocietyActa Medica Okayama2694-2453352023Highly Stretchable Stress-Strain Sensor from Elastomer Nanocomposites with Movable Cross-links and Ketjenblack394405ENRyoheiIkuraDepartment of Macromolecular Science, Graduate School of Science and Forefront Research Center for Fundamental Sciences, Osaka UniversityKotaKajimotoDepartment of Macromolecular Science, Graduate School of Science, Osaka UniversityJunsuParkDepartment of Macromolecular Science, Graduate School of Science and Forefront Research Center for Fundamental Sciences, Osaka UniversityShunsukeMurayamaGraduate School of Organic Materials Engineering, Yamagata UniversityYuseiFujiwaraDepartment of Mechanical Engineering, Osaka Institute of TechnologyMotofumiOsakiDepartment of Macromolecular Science, Graduate School of Science and Forefront Research Center for Fundamental Sciences, Osaka UniversityTomohiroSuzukiKanagawa Technical Center, Yushiro Chemical Industry Co., Ltd.HidenoriShirakawaKanagawa Technical Center, Yushiro Chemical Industry Co., Ltd.YujiroKitamuraKanagawa Technical Center, Yushiro Chemical Industry Co., Ltd.HiroakiTakahashiKanagawa Technical Center, Yushiro Chemical Industry Co., Ltd.YasumasaOhashiKanagawa Technical Center, Yushiro Chemical Industry Co., Ltd.SeijiObataResearch Core for Interdisciplinary Sciences, Okayama UniversityAkiraHaradaSANKEN (The Institute of Scientific and Industrial Research), Osaka UniversityYukaIkemotoJapan Synchrotron Radiation Research InstituteYutaNishinaResearch Core for Interdisciplinary Sciences, Okayama UniversityYasutomoUetsujiDepartment of Mechanical Engineering, Osaka Institute of TechnologyGoMatsubaGraduate School of Organic Materials Engineering, Yamagata UniversityYoshinoriTakashimaDepartment of Macromolecular Science, Graduate School of Science and Forefront Research Center for Fundamental Sciences, Osaka UniversityPractical applications like very thin stress-strain sensors require high strength, stretchability, and conductivity, simultaneously. One of the approaches is improving the toughness of the stress-strain sensing materials. Polymeric materials with movable cross-links in which the polymer chain penetrates the cavity of cyclodextrin (CD) demonstrate enhanced strength and stretchability, simultaneously. We designed two approaches that utilize elastomer nanocomposites with movable cross-links and carbon filler (ketjenblack, KB). One approach is mixing SC (a single movable cross-network material), a linear polymer (poly(ethyl acrylate), PEA), and KB to obtain their composite. The electrical resistance increases proportionally with tensile strain, leading to the application of this composite as a stress- strain sensor. The responses of this material are stable for over 100 loading and unloading cycles. The other approach is a composite made with KB and a movable cross-network elastomer for knitting dissimilar polymers (KP), where movable cross-links connect the CD-modified polystyrene (PSCD) and PEA. The obtained composite acts as a highly sensitive stress-strain sensor that exhibits an exponential increase in resistance with increasing tensile strain due to the polymer dethreading from the CD rings. The designed preparations of highly repeatable or highly responsive stress-strain sensors with good mechanical properties can help broaden their application in electrical devices.No potential conflict of interest relevant to this article was reported.Japan Society of Mechanical EngineersActa Medica Okayama1881-30541642022A bilevel production planning using machine learning-based customer modelingJAMDSM0037ENJunNAKAOGraduate School of Natural Science and Technology, Okayama UniversityTatsushiNISHIGraduate School of Natural Science and Technology, Okayama UniversityMass customization is an important strategy to improve production systems to satisfy customers’ preferences while maintaining production efficiency for mass production. Module production is one of the ways to achieve mass customization, and products are produced by combining modules. In the module production, it becomes much more important for manufacturing companies to reflect customers’ preferences for selling products. The manufacturer can increase its total profit by providing customized products that satisfy customers’ preferences by increasing customers’ satisfaction. In conventional production planning, there are some cases where module production is conducted by the demands from customers’ preferences. However, the customer decision-making model has not been employed in the production planning model. In this paper, a production planning model incorporating customers’ preferences is developed. The customers’ purchasing behavior is generated by using a machine learning model. Customer segmentation is conducted by clustering data that uses the purchase data of multiple customers. The resulting production planning model is a bilevel production planning problem consisting of a single company and multiple customers. Each company can sell products that combine modules that customers require in each segment. We show that the proposed model can obtain higher customers’ satisfaction with greater profits than the model that does not employ the customers’ purchasing model.No potential conflict of interest relevant to this article was reported.Japan Society of Mechanical EngineersActa Medica Okayama1881-30541642022Adaptive heterogeneous particle swarm optimization with comprehensive learning strategyJAMDSM0035ENZiangLIUFaculty of Natural Science and Technology, Okayama UniversityTatsushiNISHIFaculty of Natural Science and Technology, Okayama UniversityThis paper proposes an adaptive heterogeneous particle swarm optimization with a comprehensive learning strategy for solving single-objective constrained optimization problems. In this algorithm, particles can use an exploration strategy and an exploitation strategy to update their positions. The historical success rates of the two strategies are used to adaptively control the adoption rates of strategies in the next iteration. The search strategy in the canonical particle swarm optimization algorithm is based on elite solutions. As a result, when no particles can discover better solutions for several generations, this algorithm is likely to fall into stagnation. To respond to this challenge, a new strategy is proposed to explore the neighbors of the elite solutions in this study. Finally, a constraint handling method is equipped to the proposed algorithm to make it be able to solve constrained optimization problems. The proposed algorithm is compared with the canonical particle swarm optimization, differential evolution, and several recently proposed algorithms on the benchmark test suite. The Wilcoxon signed-rank test results show that the proposed algorithm is significantly better on most of the benchmark problems compared with the competitors. The proposed algorithm is also applied to solve two real-world mechanical engineering problems. The experimental results show that the proposed algorithm performs consistently well on these problems.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2075-47011382023Microstructural Control and Alloy Design for Improving the Resistance to Delayed Fracture of Ultrahigh-Strength Automotive Steel Sheets1368ENTakehideSenumaDepartment of Mechanical and Systems Engineering, Okayama UniversityMitsuhiroOkayasuDepartment of Mechanical and Systems Engineering, Okayama UniversityHardyMohrbacherNiobelCon BVThe demand for higher-strength automotive steel sheets has increased significantly for lightweight and safe body concepts. However, the increment of the steel strength is often limited by the potential occurrence of delayed fracture. This paper discusses proper microstructure control and alloy design to improve the resistance against the delayed fracture of ultrahigh-strength automotive steel sheets in order to increase the usable upper limit of their strength and provides basic data serving as a practical guide for solving the problem of delayed fracture in ultrahigh-strength automotive steel sheets. It is confirmed that grain refinement, the appropriate dual-phase structure of martensite with ferrite or retained austenite, and surface decarburization, increase the resistance to delayed fracture. In terms of alloy design, the effects of Nb, Mo, and B on the delayed fracture resistance of hot-stamped steels have been investigated. The results suggest that there are other reasons for Nb to improve delayed fracture resistance in addition to grain refinement and the ability to trap hydrogen by its precipitates, as has been conventionally believed. Regarding Mo, it was clearly demonstrated that the segregation of this element at the grain boundary plays a main role in improving the delayed fracture resistance.No potential conflict of interest relevant to this article was reported.Proceedings of the National Academy of SciencesActa Medica Okayama0027-8424119432022Structures and mechanisms of actin ATP hydrolysise2122641119ENYusukeKanematsuGraduate School of Information Sciences, Hiroshima City UniversityAkihiroNaritaStructural Biology Research Center, Graduate School of Science, Nagoya UniversityToshiroOdaFaculty of Health and Welfare, Tokai Gakuin UniversityRyotaroKoikeGraduate School of Informatics, Nagoya UniversityMotonoriOtaGraduate School of Informatics, Nagoya UniversityYuTakanoGraduate School of Information Sciences, Hiroshima City UniversityKeiMoritsuguGraduate School of Medical Life Science, Yokohama City UniversityIkukoFujiwaraGraduate School of Science, Osaka City UniversityKotaroTanakaStructural Biology Research Center, Graduate School of Science, Nagoya UniversityHideyukiKomatsuDepartment of Bioscience and Bioinformatics, Graduate School of Computer Science and Systems Engineering, Kyushu Institute of TechnologyTakayukiNagaeSynchrotron Radiation Research Center, Nagoya UniversityNobuhisaWatanabeSynchrotron Radiation Research Center, Nagoya UniversityMitsusadaIwasaGraduate School of Informatics, Nagoya UniversityYuichiroMaédaResearch Institute for Interdisciplinary Science, Okayama UniversityShuichiTakedaResearch Institute for Interdisciplinary Science, Okayama UniversityThe major cytoskeleton protein actin undergoes cyclic transitions between the monomeric G-form and the filamentous F-form, which drive organelle transport and cell motility. This mechanical work is driven by the ATPase activity at the catalytic site in the F-form. For deeper understanding of the actin cellular functions, the reaction mechanism must be elucidated. Here, we show that a single actin molecule is trapped in the F-form by fragmin domain-1 binding and present their crystal structures in the ATP analog-, ADP-Pi-, and ADP-bound forms, at 1.15-Å resolutions. The G-to-F conformational transition shifts the side chains of Gln137 and His161, which relocate four water molecules including W1 (attacking water) and W2 (helping water) to facilitate the hydrolysis. By applying quantum mechanics/molecular mechanics calculations to the structures, we have revealed a consistent and comprehensive reaction path of ATP hydrolysis by the F-form actin. The reaction path consists of four steps: 1) W1 and W2 rotations; 2) PG–O3B bond cleavage; 3) four concomitant events: W1–PO3− formation, OH− and proton cleavage, nucleophilic attack by the OH− against PG, and the abstracted proton transfer; and 4) proton relocation that stabilizes the ADP-Pi–bound F-form actin. The mechanism explains the slow rate of ATP hydrolysis by actin and the irreversibility of the hydrolysis reaction. While the catalytic strategy of actin ATP hydrolysis is essentially the same as those of motor proteins like myosin, the process after the hydrolysis is distinct and discussed in terms of Pi release, F-form destabilization, and global conformational changes.No potential conflict of interest relevant to this article was reported.IOP PublishingActa Medica Okayama0021-492262SJ2023Acoustic metasurfaces and topological phononics for acoustic/elastic device designSJ0803ENKenjiTsurutaDepartment of Electrical and Electronic Engineering, Okayama UniversityThis paper reviews recent progress in acoustic metasurfaces and the novel concept of "topological acoustic/phononics" for designing compact yet efficient acoustic devices. After a brief review of this research area and its impact on ultrasonic technologies, some of the efforts to develop highly efficient sound absorption devices using acoustic metasurfaces are introduced. A resonance-based mechanism to achieve efficient absorption in metasurface structures thinner than the wavelength of the incident sound is briefly discussed, and its extensions to a broad spectrum are highlighted. Next, a valley topological phononic system is introduced, and its applications to the design of phononic waveguides are exemplified. The band structure design for extracting topologically protected edge modes is shown together with a numerical and experimental demonstration of the robustness of phononic waveguides constructed in both acoustic and elastic regimes.No potential conflict of interest relevant to this article was reported.MDPI AGActa Medica Okayama1422-00672452023Revisiting Cryptocyanine Dye, NK-4, as an Old and New Drug: Review and Future Perspectives4411ENShihuiLiuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityToshihikoMatsuoGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityTakumiAbeGraduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityNK-4 plays a key role in the treatment of various diseases, such as in hay fever to expect anti-allergic effects, in bacterial infections and gum abscesses to expect anti-inflammatory effects, in scratches, cuts, and mouth sores from bites inside the mouth for enhanced wound healing, in herpes simplex virus (HSV)-1 infections for antiviral effects, and in peripheral nerve disease that causes tingling pain and numbness in hands and feet, while NK-4 is used also to expect antioxidative and neuroprotective effects. We review all therapeutic directions for the cyanine dye NK-4, as well as the pharmacological mechanism of NK-4 in animal models of related diseases. Currently, NK-4, which is sold as an over-the-counter drug in drugstores, is approved for treating allergic diseases, loss of appetite, sleepiness, anemia, peripheral neuropathy, acute suppurative diseases, wounds, heat injuries, frostbite, and tinea pedis in Japan. The therapeutic effects of NK-4’s antioxidant and neuroprotective properties in animal models are now under development, and we hope to apply these pharmacological effects of NK-4 to the treatment of more diseases. All experimental data suggest that different kinds of utility of NK-4 in the treatment of diseases can be developed based on the various pharmacological properties of NK-4. It is expected that NK-4 could be developed in more therapeutic strategies to treat many types of diseases, such as neurodegenerative and retinal degenerative diseases.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama1999-48931612023Three Diverse Applications of General-Purpose Parameter Optimization Algorithm45ENYuanzhiHuoDepartment of Information and Communication Systems, Okayama UniversityPradiniPuspitaningayuDepartment of Information and Communication Systems, Okayama UniversityNobuoFunabikiDepartment of Information and Communication Systems, Okayama UniversityKazushiHamazakiDepartment of Information and Communication Systems, Okayama UniversityMinoruKuribayashiDepartment of Information and Communication Systems, Okayama UniversityYihanZhaoDepartment of Mechanical Engineering, Shonan Institute of TechnologyKazuyukiKojimaDepartment of Mechanical Engineering, Shonan Institute of TechnologyParameters often take key roles in determining the accuracy of algorithms, logics, and models for practical applications. Previously, we have proposed a general-purpose parameter optimization algorithm, and studied its applications in various practical problems. This algorithm optimizes the parameter values by repeating small changes of them based on a local search method with hill-climbing capabilities. In this paper, we present three diverse applications of this algorithm to show the versatility and effectiveness. The first application is the fingerprint-based indoor localization system using IEEE802.15.4 devices called FILS15.4 that can detect the location of a user in an indoor environment. It is shown that the number of fingerprints for each detection point, the fingerprint values, and the detection interval are optimized together, and the average detection accuracy exceeds 99%. The second application is the human face contour approximation model that is described by a combination of half circles, line segments, and a quadratic curve. It is shown that the simple functions can well approximate the face contour of various persons by optimizing the center coordinates, radii, and coefficients. The third application is the computational fluid dynamic (CFD) simulation to estimate temperature changes in a room. It is shown that the thermal conductivity is optimized to make the average temperature difference between the estimated and measured 0.22 ℃.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2071-10501512022Interspecific Variability in Growth Characteristics and Phytoremediation of Cu by Free-Floating Azolla Macrophytes497ENMuhammad ShahbazAkhtarDepartment of Environmental Sciences, Forman Christian College UniversitySohaibAslamDepartment of Environmental Sciences, Forman Christian College UniversityAllahDittaDepartment of Environmental Sciences, Shaheed Benazir Bhutto UniversityBedur Faleh A.AlbalawiDepartment of Biology, University of TabukYokoOkiDepartment of Environmental Management Engineering, Graduate School of Environmental and Life Science, Okayama UniversityYoshitakaNakashimaDepartment of Environmental Management Engineering, Graduate School of Environmental and Life Science, Okayama UniversityThe phytoremediation potential of aquatic plants, particularly for Cu, is scarcely reported in the pertinent literature. In this regard, differential growth behavior and phytoaccumulation ability of three free-floating Azolla species (A. japonica, A. pinnata, and A. hybrid) were evaluated in a climatically controlled (a temperature of 25/20 degrees C, light/dark 16/8 h, a light intensity of 60 mu mol m(-2) s(-1), and a relative humidity of 65%) microcosm study. Azolla plants were exposed to solutions having three Cu concentrations (0, 3, and 6 mg L-1) under two incubation periods (4 and 8 days). Different Cu treatments significantly reduced Azolla biomass during both incubation periods and A. pinnata was the most sensitive species. Azolla plants grown in aqueous solutions showed substantial variations in Cu removal capacity. Higher bioconcentration values displayed by Azolla plants indicated that these plants can be deployed as potential plants for Cu removal from Cu contaminated water. Nevertheless, the plants exposed to higher Cu concentrations displayed color changes and root detachment due to Cu phytotoxic effects which may also ultimately lead to plant death. Significant correlations between Cu removed from the aqueous solutions and Cu contents of plant biomass indicated that Cu phytoremediation by Azolla plants was due to the phytoaccumulation mechanism because the removed Cu from aqueous solutions was accumulated in plant biomass. Introduced Azolla species, i.e., A. hybrid, displayed comparable Cu removal efficiency with naturally grown Azolla species, i.e., A. japonica and A. pinnata. Tested Azolla species proved to be suitable candidates to remediate Cu contaminated water and can be deployed for phytoremediation.No potential conflict of interest relevant to this article was reported.Public Library ScienceActa Medica Okayama1932-62031792022Prevention of non-infectious pulmonary complications after intra-bone marrow stem cell transplantation in micee0273749ENYoshikoYamasuji-MaedaDepartment of Hematology and Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesHisakazuNishimoriDepartment of Hematology and Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesKeisukeSeikeDepartment of Hematology and Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesAkiraYamamotoDepartment of Hematology and Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesHideakiFujiwaraDepartment of Hematology and Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesTaigaKuroiDepartment of Hematology and Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesKyosukeSaekiDepartment of Hematology and Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesHarukoFujinagaDepartment of Hematology and Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesSachiyoOkamotoDepartment of Hematology and Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesKen-IchiMatsuokaDepartment of Hematology and Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesNobuharuFujiiDepartment of Transfusion Medicine, Okayama University HospitalTakehiroTanakaDepartment of Pathology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesMasahiroFujiiDepartment of Animal Resources, Advanced Science Research Center, Okayama UniversityKatsumiMominokiDepartment of Animal Resources, Advanced Science Research Center, Okayama UniversityTakuroKanekuraDepartment of Dermatology, Kagoshima University Graduate School of Medical and Dental SciencesYoshinobuMaedaDepartment of Hematology and Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesNon-infectious pulmonary complications including idiopathic pneumonia syndrome (IPS) and bronchiolitis obliterans syndrome (BOS), which are clinical and diagnostic manifestations of lung chronic graft-versus-host disease (GVHD), cause significant mortality after allogeneic stem cell transplantation (SCT). Increasing evidence suggests that alloantigen reactions in lung tissue play a central role in the pathogenesis of IPS and BOS; however, the mechanism is not fully understood. Several clinical and experimental studies have reported that intrabone marrow (IBM)-SCT provides high rates of engraftment and is associated with a low incidence of acute GVHD. In the present study, allogeneic SCT was conducted in mouse models of IPS and BOS, to compare intravenous (IV)-SCT with IBM-SCT. Allogeneic IBM-SCT improved the clinical and pathological outcomes of pulmonary complications compared to those of IV-SCT. The mechanisms underlying the reductions in pulmonary complications in IBM-SCT mice were explored. The infiltrating lung cells were mainly CD11b+ myeloid and CD3+ T cells, in the same proportions as in transplanted donor cells. In an in vivo bioluminescence imaging, a higher proportion of injected donor cells was detected in the lung during the early phase (1 h after IV-SCT) than after IBM-SCT (16.7 +/- 1.1 vs. 3.1 +/- 0.7 x 10(5) photons/s/animal, IV-SCT vs. IBM-SCT, P = 1.90 x 10(-10)). In the late phase (5 days) after SCT, there were also significantly more donor cells in the lung after IV-SCT than after IBM-SCT or allogeneic-SCT (508.5 +/- 66.1 vs. 160.1 +/- 61.9 x 10(6) photons/s/animal, IV-SCT vs. IBM-SCT, P = 0.001), suggesting that the allogeneic reaction induces sustained donor cell infiltration in the lung during the late phase. These results demonstrated that IBM-SCT is capable of reducing injected donor cells in the lung; IBM-SCT decreases donor cell infiltration. IBM-SCT therefore represents a promising transplantation strategy for reducing pulmonary complications, by suppressing the first step in the pathophysiology of chronic GVHD.No potential conflict of interest relevant to this article was reported.Nature PortfolioActa Medica Okayama2045-23221212022Defect-free and crystallinity-preserving ductile deformation in semiconducting Ag2S19458ENMasaakiMisawaFaculty of Natural Science and Technology, Okayama UniversityHinataHokyoDepartment of Physics, Kumamoto UniversityShogoFukushimaDepartment of Physics, Kumamoto UniversityKoheiShimamuraDepartment of Physics, Kumamoto UniversityAkihideKouraDepartment of Physics, Kumamoto UniversityFuyukiShimojoDepartment of Physics, Kumamoto UniversityRajiv K.KaliaCollaboratory for Advanced Computing and Simulations, Department of Physics and Astronomy, Department of Computer Science, Department of Chemical Engineering and Materials Science, and Department of Biological Science, University of Southern CaliforniaAiichiroNakanoCollaboratory for Advanced Computing and Simulations, Department of Physics and Astronomy, Department of Computer Science, Department of Chemical Engineering and Materials Science, and Department of Biological Science, University of Southern CaliforniaPriyaVashishtaCollaboratory for Advanced Computing and Simulations, Department of Physics and Astronomy, Department of Computer Science, Department of Chemical Engineering and Materials Science, and Department of Biological Science, University of Southern CaliforniaTypical ductile materials are metals, which deform by the motion of defects like dislocations in association with non-directional metallic bonds. Unfortunately, this textbook mechanism does not operate in most inorganic semiconductors at ambient temperature, thus severely limiting the development of much-needed flexible electronic devices. We found a shear-deformation mechanism in a recently discovered ductile semiconductor, monoclinic-silver sulfide (Ag2S), which is defect-free, omni-directional, and preserving perfect crystallinity. Our first-principles molecular dynamics simulations elucidate the ductile deformation mechanism in monoclinic-Ag2S under six types of shear systems. Planer mass movement of sulfur atoms plays an important role for the remarkable structural recovery of sulfur-sublattice. This in turn arises from a distinctively high symmetry of the anion-sublattice in Ag2S, which is not seen in other brittle silver chalcogenides. Such mechanistic and lattice-symmetric understanding provides a guideline for designing even higher-performance ductile inorganic semiconductors.No potential conflict of interest relevant to this article was reported.Public Library ScienceActa Medica Okayama1932-62031772022Is attention branch network effective in classifying dental implants from panoramic radiograph images by deep learning?e0269016ENShintaroSukegawaDepartment of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityKazumasaYoshiiDepartment of Intelligence Science and Engineering, Graduate School of Natural Science and Technology, Gifu UniversityTakeshiHaraDepartment of Electrical, Electronic and Computer Engineering, Faculty of Engineering, Gifu UniversityFutaTanakaDepartment of Electrical, Electronic and Computer Engineering, Faculty of Engineering, Gifu UniversityKatsusukeYamashitaPolytechnic Center KagawaTutaroKagayaDepartment of Intelligence Science and Engineering, Graduate School of Natural Science and Technology, Gifu UniversityKeisukeNakanoDepartment of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityKiyofumiTakabatakeDepartment of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityHotakaKawaiDepartment of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityHitoshiNagatsukaDepartment of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityYoshihikoFurukiDepartment of Oral and Maxillofacial Surgery, Kagawa Prefectural Central HospitalAttention mechanism, which is a means of determining which part of the forced data is emphasized, has attracted attention in various fields of deep learning in recent years. The purpose of this study was to evaluate the performance of the attention branch network (ABN) for implant classification using convolutional neural networks (CNNs). The data consisted of 10191 dental implant images from 13 implant brands that cropped the site, including dental implants as pretreatment, from digital panoramic radiographs of patients who underwent surgery at Kagawa Prefectural Central Hospital between 2005 and 2021. ResNet 18, 50, and 152 were evaluated as CNN models that were compared with and without the ABN. We used accuracy, precision, recall, specificity, F1 score, and area under the receiver operating characteristics curve as performance metrics. We also performed statistical and effect size evaluations of the 30-time performance metrics of the simple CNNs and the ABN model. ResNet18 with ABN significantly improved the dental implant classification performance for all the performance metrics. Effect sizes were equivalent to "Huge" for all performance metrics. In contrast, the classification performance of ResNet50 and 152 deteriorated by adding the attention mechanism. ResNet18 showed considerably high compatibility with the ABN model in dental implant classification (AUC = 0.9993) despite the small number of parameters. The limitation of this study is that only ResNet was verified as a CNN; further studies are required for other CNN models.No potential conflict of interest relevant to this article was reported.IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INCActa Medica Okayama2169-3536102022Effectiveness of Tactile Warning and Voice Command for Enhancing Safety of Drivers9385493866ENAtsuoMurataDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversityToshihisaDoiDepartment of Living Environment Design, Graduate School of Human Life and Ecology, Osaka Metropolitan UniversityWaldemarKarwowskiEngineering and Management Systems, University of Central Florida (Life Senior Member, IEEE)Safety is impaired when drivers are required to perform main driving task (tracking of own car, distance maintenance between own car and a leading car, and response to target objects) and secondary task simultaneously, for example, responding to target cars on the road while operating in-vehicle equipment. A two-factor (presence or absence of tactile warning by input modality (no secondary task, voice command for a secondary task, and manual input for a secondary task)) within-subject design of ten licensed males was used to investigate how to compensate for safety impairments (decreased performance of a main and a secondary task such as increased tracking error during driving or increased reaction time to target cars on the road). We investigated whether the use of tactile warnings transmitted via left and right thighs for detecting road objects and voice command to operate in-vehicle equipment could compensate for safety impairments such as the increased reaction time to target cars on the road, the increase of detection error of target cars, or increased tracking error in driving. The accuracy and speed of responses to target cars encountered during driving were reduced when a driver was asked to perform the main and the secondary task simultaneously compared to situations performing only the main driving task (tracking, distance maintenance, and response to target cars). The availability of a tactile warning system for road objects compensated for these diminished performance measures, including slower response times and the increased detection error of target cars. Likewise, voice command contributed to enhanced performance of the main driving task such as decrease of tracking error.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama1422-006723192022Molecular Mechanisms Underlying Ca2+/Calmodulin-Dependent Protein Kinase Kinase Signal Transduction11025ENHiroshiTokumitsuApplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityHiroyukiSakagamiDepartment of Anatomy, Kitasato University School of MedicineCa2+/calmodulin-dependent protein kinase kinase (CaMKK) is the activating kinase for multiple downstream kinases, including CaM-kinase I (CaMKI), CaM-kinase IV (CaMKIV), protein kinase B (PKB/Akt), and 5'AMP-kinase (AMPK), through the phosphorylation of their activation-loop Thr residues in response to increasing the intracellular Ca2+ concentration, as CaMKK itself is a Ca2+/CaM-dependent enzyme. The CaMKK-mediated kinase cascade plays important roles in a number of Ca2+-dependent pathways, such as neuronal morphogenesis and plasticity, transcriptional activation, autophagy, and metabolic regulation, as well as in pathophysiological pathways, including cancer progression, metabolic syndrome, and mental disorders. This review focuses on the molecular mechanism underlying CaMKK-mediated signal transduction in normal and pathophysiological conditions. We summarize the current knowledge of the structural, functional, and physiological properties of the regulatory kinase, CaMKK, and the development and application of its pharmacological inhibitors.No potential conflict of interest relevant to this article was reported.IEEE - Inst Electrical Electronics Engineers IncActa Medica Okayama2169-3536102022Sensitivity of PERCLOS70 to Drowsiness Level: Effectiveness of PERCLOS70 to Prevent Crashes Caused by Drowsiness7080670814ENAtsuoMurataDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversityToshihisaDoiDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversityWaldemarKarwowskiDepartment of Engineering and Management Systems, University of Central FloridaIt has been reported that many crashes are caused by drowsiness. Thus, it is critical to predict the occurrence of severe drowsiness that may result in a crash by means of an effective measure. The aim of this study was to investigate whether percentage closure (PERCLOS) of 70% was useful for evaluating drowsiness level of individual drivers and preventing crashes caused by drowsy driving using a driving simulator system. The first experiment measured PERCLOS70 during both aroused and drowsy states in a driving simulator task and investigated how PERCLOS70 changes when a participant fell asleep. In the second experiment, we measured PERCLOS70 and investigated the relation between PERCLOS70 and Karolinska Sleepiness Scale (KSS) ratings during a simulated driving task. The aggregated mean PERCLOS70 was significantly higher when participants fell asleep than when they were aroused. This tendency was also observed for individual participants. The aggregated mean PERCLOS70 was found to be sensitive to changes in KSS scores and increased with increasing KSS score. Linear trend analysis revealed a significant increasing trend for PERCLOS70 as a function of the KSS rating. This tendency was also observed for individual participants. PERCLOS70 was found to be sensitive to the drowsiness level both for data aggregated across all participants and data for individual participants. The main findings of the two experiments reported herein suggest that PERCLOS70 can be used effectively to evaluate drowsiness of individual drivers and prevent crashes caused by drowsy driving.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama1424-822022132022A Business-to-Business Collaboration System That Promotes Data Utilization While Encrypting Information on the Blockchain4909ENHiroakiNasuGraduate School of Natural Science and Technology, Okayama UniversityYutaKoderaFaculty of Natural Science and Technology, Okayama UniversityYasuyukiNogamiFaculty of Natural Science and Technology, Okayama UniversityEnsuring the reliability of data gathering from every connected device is an essential issue for promoting the advancement of the next paradigm shift, i.e., Industry 4.0. Blockchain technology is becoming recognized as an advanced tool. However, data collaboration using blockchain has not progressed sufficiently among companies in the industrial supply chain (SC) that handle sensitive data, such as those related to product quality, etc. There are two reasons why data utilization is not sufficiently advanced in the industrial SC. The first is that manufacturing information is top secret. Blockchain mechanisms, such as Bitcoin, which uses PKI, require plaintext to be shared between companies to verify the identity of the company that sent the data. Another is that the merits of data collaboration between companies have not been materialized. To solve these problems, this paper proposes a business-to-business collaboration system using homomorphic encryption and blockchain techniques. Using the proposed system, each company can exchange encrypted confidential information and utilize the data for its own business. In a trial, an equipment manufacturer was able to identify the quality change caused by a decrease in equipment performance as a cryptographic value from blockchain and to identify the change one month earlier without knowing the quality value.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X7632022Histone Demethylase Jmjd3 Regulates the Osteogenic Differentiation and Cytokine Expressions of Periodontal Ligament Cells281290ENBoYuDepartment of Endodontics, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral DiseaseRuiWangDepartment of Endodontics, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral DiseaseHuikunLuoDepartment of Endodontics, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral DiseaseDiYangDepartment of Endodontics, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral DiseaseSimoWangDepartment of Endodontics, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral DiseaseYaqiongYuDepartment of Endodontics, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral DiseaseHirohikoOkamuraDepartment of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityLihongQiuDepartment of Endodontics, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral DiseaseOriginal Article10.18926/AMO/63722Periodontal ligament (PDL) cells are critical for the bone remodeling process in periapical lesions since they can differentiate into osteoblasts and secrete osteoclastogenesis-promoting cytokines. Post-translational histone modifications including alterations of the methylation status of H3K27 are involved in cell differentiation and inflammatory reaction. The histone demethylase Jumonji domain-containing 3 (Jmjd3) specifically removes methylation of H3K27. We investigated whether Jmjd3 is involved in the osteogenic differentiation and secretion of PDL cells’ inflammatory factors. Jmjd3 expression in periapical lesions was examined by immunostaining. Using siRNA specific for Jmjd3 or the specific Jmjd3 inhibitor GSK-J4, we determined Jmjd3’s roles in osteogenic differentiation and cytokine production by real-time RT-PCR. The locations of Jmjd3 and NF-κB were analyzed by immunocytochemistry. Compared to healthy PDLs, the periapical lesion samples showed higher Jmjd3 expression. Treatment with GSK-J4 or Jmjd3 siRNA suppressed PDL cells’ osteogenic differentiation by suppressing the expressions of bone-related genes (Runx2, Osterix, and osteocalcin) and mineralization. Jmjd3 knockdown decreased the expressions of cytokines (TNF-α, IL-1β, and IL-6) induced by lipopolysaccharide extracted from Porphyromonas endodontalis (Pe-LPS). Pe-LPS induced the nuclear translocations of Jmjd3 and NF-κB; the latter was inhibited by GSK-J4 treatment. Jmjd3 appears to regulate PDL cells’ osteogenic differentiation and proinflammatory cytokine expressions.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2078-24891352022A Proposal of the Fingerprint Optimization Method for the Fingerprint-Based Indoor Localization System with IEEE 802.15.4 Devices211ENYuanzhiHuoDepartment of Electrical and Communication Engineering, Okayama UniversityPradiniPuspitaningayuDepartment of Electrical and Communication Engineering, Okayama UniversityNobuoFunabikiDepartment of Electrical and Communication Engineering, Okayama UniversityKazushiHamazakiDepartment of Electrical and Communication Engineering, Okayama UniversityMinoruKuribayashiDepartment of Electrical and Communication Engineering, Okayama UniversityKazuyukiKojimaMechanical Engineering, Shonan Institute of TechnologyNowadays, human indoor localization services inside buildings or on underground streets are in strong demand for various location-based services. Since conventional GPS cannot be used, indoor localization systems using wireless technologies have been extensively studied. Previously, we studied a fingerprint-based indoor localization system using IEEE802.15.4 devices, called FILS15.4, to allow use of inexpensive, tiny, and long-life transmitters. However, due to the narrow channel band and the low transmission power, the link quality indicator (LOI) used for fingerprints easily fluctuates by human movements and other uncontrollable factors. To improve the localization accuracy, FILS15.4 restricts the detection granularity to one room in the field, and adopts multiple fingerprints for one room, considering fluctuated signals, where their values must be properly adjusted. In this paper, we present a fingerprint optimization method for finding the proper fingerprint parameters in FILS15.4 by extending the existing one. As the training phase using the measurement LQI, it iteratively changes fingerprint values to maximize the newly defined score function for the room detecting accuracy. Moreover, it automatically increases the number of fingerprints for a room if the accuracy is not sufficient. For evaluations, we applied the proposed method to the measured LQI data using the FILS15.4 testbed system in the no. 2 Engineering Building at Okayama University. The validation results show that it improves the average detection accuracy (at higher than 97%) by automatically increasing the number of fingerprints and optimizing the values.No potential conflict of interest relevant to this article was reported.IOP Publishing LtdActa Medica Okayama2399-6528642022Resonance modes of a metal-semiconductor-metal multilayer mediated by electric charge045006ENKazumaIsobeDepartment of Advanced Mechanics, Graduate School of Natural Science and Technology, Okayama UniversityKatsunoriHanamuraSchool of Engineering, Department of Mechanical Engineering, Tokyo Institute of TechnologyElectromagnetic fields around metal-semiconductor-metal (MSM) multilayers with square island top layers were numerically simulated to elucidate the difference in physics between the circuit resonance and Fabry-Perot interference mediated by the surface plasmon polaritons (SPP). In the current study, the top and bottom metal layers were made of gold, and the intermediate semiconductor layer was a gallium antimony (GaSb). The lumped-element and Fabry-Perot interference models showed less accuracy when the island width of the MSM multilayer was comparatively smaller. Since the capacitor and SPP could not be supported between the top and bottom gold layers, the anti-reflection mode of the gold-GaSb bilayer mainly affected the absorptance. However, when the width of the island was sufficiently large, the time-lapse development of the electromagnetic fields at resonant wavelengths showed strong electric and magnetic responses relating to the circuit resonance. Simultaneously, the electric fields depicted the movement of the electric charge, which coupled to the short-range surface plasmon polariton (SRSP) existing at the thin GaSb layer sandwiched by two gold layers. The wavelength of the SRSP approximately corresponded to that of the Fabry-Perot interference. It was revealed that the lumped-element and Fabry-Perot interference models indicated the same resonant mode from two different perspectives in physics.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X7622022Overexpression of Adenovirus E1A Reverses Transforming Growth Factor-β-induced Epithelial-mesenchymal Transition in Human Esophageal Cancer Cells203215ENTomoyaMasudaDepartment of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesHiroshiTazawaDepartment of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesYuuriHashimotoDepartment of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesTakeshiIedaDepartment of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesSatoruKikuchiDepartment of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesShinjiKurodaDepartment of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesKazuhiroNomaDepartment of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesYasuoUrataOncolys BioPharma Inc.ShunsukeKagawaDepartment of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesToshiyoshiFujiwaraDepartment of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesOriginal Article10.18926/AMO/63425The epithelial-mesenchymal transition (EMT), a normal biological process by which epithelial cells acquire a mesenchymal phenotype, is associated with migration, metastasis, and chemoresistance in cancer cells, and with poor prognosis in patients with esophageal cancer. However, therapeutic strategies to inhibit EMT in tumor environments remain elusive. Here, we show the therapeutic potential of telomerase-specific replication- competent oncolytic adenovirus OBP-301 in human esophageal cancer TE4 and TE6 cells with an EMT phenotype. Transforming growth factor-β (TGF-β) administration induced the EMT phenotype with spindleshaped morphology, upregulation of mesenchymal markers and EMT transcription factors, migration, and chemoresistance in TE4 and TE6 cells. OBP-301 significantly inhibited the EMT phenotype via E1 accumulation. EMT cancer cells were susceptible to OBP-301 via massive autophagy induction. OBP-301 suppressed tumor growth and lymph node metastasis of TE4 cells co-inoculated with TGF-β-secreting fibroblasts. Our results suggest that OBP-301 inhibits the TGF-β-induced EMT phenotype in human esophageal cancer cells. OBP-301-mediated E1A overexpression is a promising antitumor strategy to inhibit EMT-mediated esophageal cancer progression.No potential conflict of interest relevant to this article was reported.The Society for Free Radical Research JapanActa Medica Okayama0912-00097022022Mechanisms of action of radon therapy on cytokine levels in normal mice and rheumatoid arthritis mouse model154159ENTakahiroKataokaGraduate School of Health Sciences, Okayama UniversityShotaNaoeGraduate School of Health Sciences, Okayama UniversityKaitoMurakamiGraduate School of Health Sciences, Okayama UniversityRyoheiYukimineGraduate School of Health Sciences, Okayama UniversityYukiFujimotoGraduate School of Health Sciences, Okayama UniversityNorieKanzakiNingyo-toge Environmental Engineering Center, Japan Atomic Energy AgencyAkihiroSakodaNingyo-toge Environmental Engineering Center, Japan Atomic Energy AgencyFumihiroMitsunobuGraduate School of Medicine Dentistry and Pharmaceutical Sciences, Okayama UniversityKiyonoriYamaokaGraduate School of Health Sciences, Okayama UniversityThe typical indication of radon therapy is rheumatoid arthritis. Although there are several reports that radon therapy has regulation effects on Th17 cells, there has been no study reporting that radon inhalation affects the immune balance among Th1, Th2, and Th17. The purpose of this study is to examine the cytokine changes after radon inhalation. BALB/c mice inhaled radon at 2,000 Bq/m3 for 2 or 4 weeks. SKG/Jcl mice inhaled radon at 2,000 Bq/m3 for 4 weeks after zymosan administration. The results showed that radon inhalation for 4 weeks activated the immune response of Th1, Th2, and Th17. Moreover, the balance among them was not lost by radon inhalation. Radon inhalation for 4 weeks decreased superoxide dismutase activity and increased catalase activity in spleen. These findings suggest that an imbalance of oxidative stress may contribute to activate the immune response. Although zymosan administration activated Th17 immune response and decreased Th1 and Th2 immune response in SKG/Jcl mice, most cytokines related to Th1, Th2, and Th17 approached the normal level by radon inhalation. These findings suggested that radon inhalation has a different action between SKG/Jcl mice and normal BABL/c mice. This may indicate that radon inhalation has an immunomodulation function.No potential conflict of interest relevant to this article was reported.IEEE－Inst Electrical Electronics Engineers Inc.Acta Medica Okayama2169-3536102022Implications for Risk Taking Behavior Leading to Crashes or Disasters-Effects of Perceived Risk on Risk Taking Decision3496034969ENAtsuoMurataDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversityThe aim of this study was to investigate the effects of the outcome in a risk averse sure option and the perceived risk of the worst outcome on risk taking behaviors and to get insights into prevention of disasters or crashes caused by risk taking. Because of cognitive biases to optimistically underestimate a risk, it is generally difficult to recognize rationally a risk and its consequence leading to a disaster or crash. Therefore, the recognition of the gap between the perceive risk and the real risk is a very important issue, because such a gap might cause risk taking behaviors or decisions, leading to a disaster or crash. Using three decision-making situations with different scenarios, we measured the perceived risk at which the decision changed from a risk averse alternative to a risk taking one as a function of the outcome in a sure risk averse alternative and the frame (positive or negative frame in a scenario of decision making). The perceived risk at which the decision shifted from a risk averse alternative to a risk taking one decreased with the increase of the outcome in a risk averse alternative. The perceived risk was lower when the decision-making scenario was positively framed. Irrespective of the difference of decision-making scenarios, there existed a self-reported risk (probability) that changed a decision from a risk averse alternative to a risk taking one. Applying the framework of decision making of this study to a few cases of crashes or disasters, some implications for preventing disasters or crashes were given.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2073-44251322022Dkk3/REIC Deficiency Impairs Spermiation, Sperm Fibrous Sheath Integrity and the Sperm Motility of Mice285ENRuizhiXueDepartment of Urology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesWenfengLinDepartment of Urology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesHirofumiFujitaDepartment of Cytology and Histology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesJingkaiSunDepartment of Urology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesRieKinoshitaDepartment of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesKazuhikoOchiaiLaboratory of Veterinary Hygiene, Nippon Veterinary and Life Science UniversityJunichiroFutamiDepartment of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityMasamiWatanabeDepartment of Urology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesHideyoOhuchiDepartment of Cytology and Histology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesMasakiyoSakaguchiDepartment of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesZhengyanTangDepartment of Urology, Xiangya Hospital, Central South UniversityPengHuangDepartment of Urology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesYasutomoNasuDepartment of Urology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesHiromiKumonInnovation Center Okayama for Nanobio-Targeted Therapy, Okayama UniversityThe role of Dickkopf-3 (Dkk3)/REIC (The Reduced Expression in Immortalized Cells), a Wnt-signaling inhibitor, in male reproductive physiology remains unknown thus far. To explore the functional details of Dkk3/REIC in the male reproductive process, we studied the Dkk3/REIC knock-out (KO) mouse model. By examining testicular sections and investigating the sperm characteristics (count, vitality and motility) and ultrastructure, we compared the reproductive features between Dkk3/REIC-KO and wild-type (WT) male mice. To further explore the underlying molecular mechanism, we performed RNA sequencing (RNA-seq) analysis of testicular tissues. Our results showed that spermiation failure existed in seminiferous tubules of Dkk3/REIC-KO mice, and sperm from Dkk3/REIC-KO mice exhibited inferior motility (44.09 +/- 8.12% vs. 23.26 +/- 10.02%, p < 0.01). The Ultrastructure examination revealed defects in the sperm fibrous sheath of KO mice. Although the average count of Dkk3/REIC-KO epididymal sperm was less than that of the wild-types (9.30 +/- 0.69 vs. 8.27 +/- 0.87, x10(6)), neither the gap (p > 0.05) nor the difference in the sperm vitality rate (72.83 +/- 1.55% vs. 72.50 +/- 0.71%, p > 0.05) were statistically significant. The RNA-seq and GO (Gene Oncology) enrichment results indicated that the differential genes were significantly enriched in the GO terms of cytoskeleton function, cAMP signaling and calcium ion binding. Collectively, our research demonstrates that Dkk3/REIC is involved in the process of spermiation, fibrous sheath integrity maintenance and sperm motility of mice.No potential conflict of interest relevant to this article was reported.Nature PortfolioActa Medica Okayama2045-23221212022The significance of ErbB2/3 in the conversion of induced pluripotent stem cells into cancer stem cells2711ENGhmkinHassanDepartment of Biotechnology and Drug Discovery, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityMaram H.ZahraDepartment of Biotechnology and Drug Discovery, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityAkimasaSenoDepartment of Biotechnology and Drug Discovery, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityMasaharuSenoDepartment of Biotechnology and Drug Discovery, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityCancer stem cells (CSCs) are suggested to be responsible for drug resistance and aggressive phenotypes of tumors. Mechanisms of CSC induction are still under investigation. Our lab has established a novel method to generate CSCs from iPSCs under a cancerous microenvironment mimicked by the conditioned medium (CM) of cancer-derived cells. Here, we analyzed the transcriptome of CSCs, which were converted from iPSCs with CM from pancreatic ductal adenocarcinoma cells. The differentially expressed genes were identified and used to explore pathway enrichment. From the comparison of the CSCs with iPSCs, genes with elevated expression were related to the ErbB2/3 signaling pathway. Inhibition of either ErbB2 with lapatinib as a tyrosine kinase inhibitor or ErbB3 with TX1-85-1 or siRNAs arrested cell proliferation, inhibited the in vitro tumorigenicity, and lead to loss of stemness in the converting cells. The self-renewal and tube formation abilities of cells were also abolished while CD24 and Oct3/4 levels were reduced, and the MAPK pathway was overactivated. This study shows a potential involvement of the ErbB2/ErbB3 pathway in CSC generation and could lead to new insight into the mechanism of tumorigenesis and the way of cancer prevention.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2073-89941412021Delayed Evacuation after a Disaster Because of Irrational Prediction of the Future Cumulative Precipitation Time Series under Asymmetry of Information6ENAtsuoMurataDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversityToshihisaDoiDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversityRinHasegawaDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversityWaldemarKarwowskiDepartment of Industrial Engineering and Management Systems, University of Central FloridaThis study investigated biased prediction of cumulative precipitation, using a variety of patterns of histories of cumulative precipitation, to explore how such biased prediction could delay evacuation or evacuation orders. The irrationality in predicting the future of cumulative precipitation was examined to obtain insights into the causes of delayed evacuation or evacuation orders using a simulated prediction of future cumulative precipitation based on the cumulative precipitation history. Anchoring and adjustment, or availability bias stemming from asymmetry of information, was observed in the prediction of cumulative precipitation, and found to delay evacuation or evacuation orders.No potential conflict of interest relevant to this article was reported.Institute of Electrical and Electronics Engineers (IEEE)Acta Medica Okayama2169-353692021Mitigation of Kernel Memory Corruption Using Multiple Kernel Memory Mechanism111651111665ENHirokiKuzuno1Intelligent Systems Laboratory, SECOM Company Ltd.ToshihiroYamauchi2Graduate School of Natural Science and Technology, Okayama UniversityOperating systems adopt kernel protection methods (e.g., mandatory access control, kernel address space layout randomization, control flow integrity, and kernel page table isolation) as essential countermeasures to reduce the likelihood of kernel vulnerability attacks. However, kernel memory corruption can still occur via the execution of malicious kernel code at the kernel layer. This is because the vulnerable kernel code and the attack target kernel code or kernel data are located in the same kernel address space. To gain complete control of a host, adversaries focus on kernel code invocations, such as function pointers that rely on the starting points of the kernel protection methods. To mitigate such subversion attacks, this paper presents multiple kernel memory (MKM), which employs an alternative design for kernel address space separation. The MKM mechanism focuses on the isolation granularity of the kernel address space during each execution of the kernel code. MKM provides two kernel address spaces, namely, i) the trampoline kernel address space, which acts as the gateway feature between user and kernel modes and ii) the security kernel address space, which utilizes the localization of the kernel protection methods (i.e., kernel observation). Additionally, MKM achieves the encapsulation of the vulnerable kernel code to prevent access to the kernel code invocations of the separated kernel address space. The evaluation results demonstrated that MKM can protect the kernel code and kernel data from a proof-of-concept kernel vulnerability that could lead to kernel memory corruption. In addition, the performance results of MKM indicate that the system call overhead latency ranges from 0.020 μs to 0.5445 μs, while the web application benchmark ranges from 196.27 μs to 6, 685.73 μs for each download access of 100,000 Hypertext Transfer Protocol sessions. MKM attained a 97.65% system benchmark score and a 99.76% kernel compilation time.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama0195-928X4332022Absorptivity Control Over the Visible to Mid-Infrared Range Using a Multilayered Film Consisting of Thermochromic Vanadium Dioxide44ENKazumaIsobeGraduate School of Natural Science and Technology, Department of Mechanical Engineering, Okayama UniversityMinoruTomiokaFaculty of Engineering, Department of Mechanical Engineering, Okayama UniversityYutakaYamadaGraduate School of Natural Science and Technology, Department of Mechanical Engineering, Okayama UniversityAkihikoHoribeGraduate School of Natural Science and Technology, Department of Mechanical Engineering, Okayama UniversityVanadium dioxide (VO<sub>2</sub>) is a phase transition material that exhibits metallic or insulating characteristics depending upon its temperature. In this study, a multilayered film consisting of <sub>2</sub>, silicon dioxide (SiO<sub>2</sub>) and gold was proposed as a metamaterial that switches its absorptivity over a broad wavelength range depending on the ambient temperature as a fundamental element of a building pigment. At high temperatures, the multilayer showed a high absorptivity at mid-infrared wavelengths, promoting radiative cooling. Simultaneously, the multilayer presented a low absorptivity in the visible and near-infrared wavelengths, enhancing sunlight absorption. The daily average heat flux can possibly be suppressed in summer in comparison with a gray body whose emissivity was 0.8. Conversely, at a lower temperatures, the multilayer showed opposite absorptivity in both the mid-infrared and visible ranges, and its daily average heat flux increased in winter. The metal–insulator phase transition of VO<sub>2</sub> caused a drastic shift of the resonant wavelength related to surface phonons and surface plasmons at an infrared wavelength, and optical interference at a visible wavelength, originating at the interface of the SiO<sub>2</sub> layer. Thus, the radiative heat flux for both sunlight absorption and radiative cooling was simultaneously controlled depending on the temperature of VO<sub>2</sub>.No potential conflict of interest relevant to this article was reported.ElsevierActa Medica Okayama2090-1232352022Spred2 controls the severity of Concanavalin A-induced liver damage by limiting interferon-gamma production by CD4(+) and CD8(+) T cells7186ENCuimingSunDepartment of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityMasayoshiFujisawaDepartment of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityToshiakiOharaDepartment of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityQiuyingLiuDepartment of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityChenCaoDepartment of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityXuYangDepartment of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityTeizoYoshimuraDepartment of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversitySteven L.KunkelDepartment of Pathology, University of Michigan Medical SchoolAkihiroMatsukawaDepartment of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityIntroduction: Mitogen-activated protein kinases (MAPKs) are involved in T cell-mediated liver damage. However, the inhibitory mechanism(s) that controls T cell-mediated liver damage remains unknown. Objectives: We investigated whether Spred2 (Sprouty-related, EVH1 domain-containing protein 2) that negatively regulates ERK-MAPK pathway has a biological impact on T cell-mediated liver damage by using a murine model. Methods: We induced hepatotoxicity in genetically engineered mice by intravenously injecting Concanavalin A (Con A) and analyzed the mechanisms using serum chemistry, histology, ELISA, qRT-PCR, Western blotting and flow cytometry. Results: Spred2-deficient mice (Spred2(-/-)) developed more sever liver damage than wild-type (WT) mice with increased interferon-gamma (IFNy) production. Hepatic ERK phosphorylation was enhanced in Spred2(-/-) mice, and pretreatment of Spred2(-/-) mice with the MAPK/ERK inhibitor U0126 markedly inhibited the liver damage and reduced IFN gamma production. Neutralization of IFNy abolished the damage with decreased hepatic Stat1 activation in Spred2(-/-) mice. IFN gamma was mainly produced from CD4(+) and CD8(+) T cells, and their depletion decreased liver damage and IFN gamma production. Transplantation of CD4(+) and/or CD8(+) T cells from Spred2(-/-) mice into RAG1(-/-) mice deficient in both T and B cells caused more severe liver damage than those from WT mice. Hepatic expression of T cell attractants, CXCL9 and CXCL10, was augmented in Spred2(-/-) mice as compared to WT mice. Conversely, liver damage, IFN gamma production and the recruitment of CD4(+) and CD8(+) T cells in livers after Con A challenge were lower in Spred2 transgenic mice, and Spred2-overexpressing CD4(+) and CD8(+) T cells produced lower levels of IFN gamma than WT cells upon stimulation with Con A in vitro. Conclusion: We demonstrated, for the first time, that Spred2 functions as an endogenous regulator of T cell IFNy production and Spred2-mediated inhibition of ERK-MAPK pathway may be an effective remedy for T cell-dependent liver damage.No potential conflict of interest relevant to this article was reported.Japan Institute of MetalsActa Medica Okayama0021-487685112021Ti–10Mo–7Al合金の焼戻し誘起マルテンサイトの形成機構405412ENYoshitoTakemotoGraduate School of Natural Science and Technology, Okayama UniversityMikikoYasunoGraduate School of Natural Science and Technology, Okayama UniversityMasakiIkemotoGraduate School of Natural Science and Technology, Okayama UniversityHiroyukiAndoFaculty of Engineering, Okayama UniversityIchiroShimizuFaculty of Engineering, Okayama University of ScienceThe formation mechanism of αAA–martensite (αAAMt) induced by tempering at 450–550℃ for a short time was investigated using Ti–10Mo–7Al alloy. The solution treated and quenched (STQ) sample was composed of β phase and a small amount of αAAMq, and a large amount of αAAMt was generated by rapid tempering at 550℃–3 s using a salt bath. However, αAAMt was completely transformed into a single β phase by aging at 200℃ for 3 min. Reversibility was observed between the αAAMt transformation and the β reverse transformation. In–situ high–temperature X–ray diffraction measurements revealed that αAAMq → β reverse transformation occurred at 200℃ and that a thermally activated αAAiso was generated at
450℃ due to the slow heating rate. In–situ optical microscopic observation of STQ sample with rapid lamp heating revealed that αAAMt was formed during heating process. However, αAAMt did not generate under following conditions; that is, a slow heating rate, thin sample plate, and a small temperature difference until tempering by preheating. On the other hand, rapid tempering using thick plate from liquid nitrogen (−196℃) to 250℃ was performed to ensure a sufficient temperature difference, but αAAMt was not generated at all.
From the cross–sectional observation of the STQ plate, it was found that αAAMq was hardly formed on the surface of the sample, but was formed abundantly inside the sample. On the other hand, in the rapidly tempered plate, a large amount of αAAMt was distributed in the surface layer than inside sample. These results suggest that the thermal compressive stress induced by rapid heat treatment contributes to the formation of α''M.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama1422-006722242021Effect of NK-5962 on Gene Expression Profiling of Retina in a Rat Model of Retinitis Pigmentosa13276ENShihuiLiuDepartment of Ophthalmology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityMaryMiyajiDepartment of Medical Neurobiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityOsamuHosoyaDepartment of Medical Neurobiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityToshihikoMatsuoDepartment of Ophthalmology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityPurpose: NK-5962 is a key component of photoelectric dye-coupled polyethylene film, designated Okayama University type-retinal prosthesis (OUReP™). Previously, we found that NK-5962 solution could reduce the number of apoptotic photoreceptors in the eyes of the Royal College of Surgeons (RCS) rats by intravitreal injection under a 12 h light/dark cycle. This study aimed to explore possible molecular mechanisms underlying the anti-apoptotic effect of NK-5962 in the retina of RCS rats. Methods: RCS rats received intravitreal injections of NK-5962 solution in the left eye at the age of 3 and 4 weeks, before the age of 5 weeks when the speed in the apoptotic degeneration of photoreceptors reaches its peak. The vehicle-treated right eyes served as controls. All rats were housed under a 12 h light/dark cycle, and the retinas were dissected out at the age of 5 weeks for RNA sequence (RNA-seq) analysis. For the functional annotation of differentially expressed genes (DEGs), the Metascape and DAVID databases were used. Results: In total, 55 up-regulated DEGs, and one down-regulated gene (LYVE1) were found to be common among samples treated with NK-5962. These DEGs were analyzed using Gene Ontology (GO) term enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG), and Reactome pathway analyses. We focused on the up-regulated DEGs that were enriched in extracellular matrix organization, extracellular exosome, and PI3K–Akt signaling pathways. These terms and pathways may relate to mechanisms to protect photoreceptor cells. Moreover, our analyses suggest that SERPINF1, which encodes pigment epithelium-derived factor (PEDF), is one of the key regulatory genes involved in the anti-apoptotic effect of NK-5962 in RCS rat retinas. Conclusions: Our findings suggest that photoelectric dye NK-5962 may delay apoptotic death of photoreceptor cells in RCS rats by up-regulating genes related to extracellular matrix organization, extracellular exosome, and PI3K–Akt signaling pathways. Overall, our RNA-seq and bioinformatics analyses provide insights in the transcriptome responses in the dystrophic RCS rat retinas that were induced by NK-5962 intravitreal injection and offer potential target genes for developing new therapeutic strategies for patients with retinitis pigmentosa.</jats:p>No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2073-899413112021Irrationality of Attitudes toward Safety under Complexity and Uncertainty Leading to Asymmetry of Information2111ENAtsuoMurataDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversitySyusukeYoshidaDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversityToshihisaDoiDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversityWaldemarKarwowskiDepartment of Industrial Engineering and Management Systems, University of Central FloridaThis study investigated how complexity and uncertainty, the probability of accidents, and the probability of financial trouble affected individuals' recognition of validity of irrational risk-seeking decisions. As a result of conducting a multiple regression analysis on the validation score for irrational risk-seeking alternative obtained by a questionnaire survey, we found that the validity score for an irrational risk-seeking alternative was higher when both complexity and uncertainty were high than when both complexity and uncertainty were low, which means that high complexity and high uncertainty in the situation of decision making more readily leads to an irrational risk-seeking behavior that might trigger a major accident. Beyond complexity and uncertainty, the damage of major accident alpha, the decrease of the probability of major accidents and the increase of the probability of financial trouble (economic factor) were also found to promote the choice of irrational risk-seeking alternatives. Some implications for safety management under high complexity and uncertainty are discussed.No potential conflict of interest relevant to this article was reported.Japan Laser Processing SocietyActa Medica Okayama1880-06881622021Formation and Its Mechanism of High-speed Micro-grooving on Metal Surface by Angled CW Laser Irradiation109114ENNozomiTauraGraduate School of Natural Science and Technology, Okayama University, JapanAkiyaMitsunobuFaculty of Engineering, Okayama University, JapanTatsuhikoSakaiNIPPON STEEL CORPORATION, JapanYasuhiroOkamotoGraduate School of Natural Science and Technology, Okayama University, JapanAkiraOkadaGraduate School of Natural Science and Technology, Okayama University, JapanIn general, pulsed lasers with high peak power have been used for the micro-groove formation. However, the processing speed is limited by the pulse repetition rate. On the other hand, CW laser can be expected to perform the high-speed processing by continuous energy input. The mechanism of micro-groove formation by CW laser was investigated by high-speed observation and the thermal fluid analysis. In the perpendicular irradiation of CW laser, the molten metal flows symmetrically around the keyhole to the backward direction, and micro-grooves remain at both edges of molten region. In contrast, in the angled irradiation, the molten metal at the reflection-side scatters as spatters. The remained molten metal flows from the reflection-side to the incident-side through the bottom of keyhole, since the recoil pressure is generated from the reflection-side to the incident-side. In addition, high-speed scanning contributes to keeping the sufficient time and force to move the molten metal in the backward direction. Then, the micro-groove remains at the reflection-side, while the upheaval is formed at the incident-side by gathering the molten metal from the reflection-side and the front of keyhole. Asymmetrical behavior of molten metal flow in angled irradiation of CW laser can create micro-groove in the reflection-side. No potential conflict of interest relevant to this article was reported.ElsevierActa Medica Okayama0167577X3072021Clarification of degradation mechanism on retinal prosthesis using photoelectric dyes coupled to polyethylene film by mass spectrometry130978ENKoichiroYamashitaGraduate School of Natural Science and Technology, Okayama UniversityMayuMitsuiGraduate School of Natural Science and Technology, Okayama UniversityToshihikoMatsuoGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityTetsuyaUchidaGraduate School of Natural Science and Technology, Okayama UniversityPhotoelectric dyes have stimulated retinal neurons by absorbing light and generating an electric potential. Therefore, a photoelectric dye was used to develop a retinal prosthesis to restore vision loss due to retinitis pigmentosa. The retinal prosthesis, referred to as a dye-coupled film, was prepared by chemically coupling the dyes to a polyethylene film surface through amide bonds. However, the coupled dyes decreased during an implantation test in a monkey eye. This study clarifies the degradation mechanism of the dye-coupled film. Since the dyes were selectively coupled to the film surface, it is difficult to detect the eliminated dyes in a solution. Therefore, a model compound that mimicked the chemical structure of the dye-coupled film by converting the carboxylic acid of dye to the amide bond is used. It was found that the elimination of the side chain, including the amide bond, occurred before the degradation of the conjugated structure according to mass spectrometry of the model compound. The degradation mechanism of the dye-coupled film was predicted based on that of the model compound. It was concluded that chemical bonds between the dye and the film surface were preferentially decomposed, leading to the detachment of the dyes from the film surface.No potential conflict of interest relevant to this article was reported.Oxford University PressActa Medica Okayama0449-30606252021Radon inhalation decreases DNA damage induced by oxidative stress in mouse organs via the activation of antioxidative functions861867ENTakahiroKataokaGraduate School of Health Sciences, Okayama UniversityHinaShutoGraduate School of Health Sciences, Okayama UniversityShotaNaoeGraduate School of Health Sciences, Okayama UniversityJunkiYanoGraduate School of Health Sciences, Okayama UniversityNorieKanzakiNingyo-toge Environmental Engineering Center, Japan Atomic Energy AgencyAkihiroSakodaNingyo-toge Environmental Engineering Center, Japan Atomic Energy AgencyHiroshiTanakaNingyo-toge Environmental Engineering Center, Japan Atomic Energy AgencyKatsumiHanamotoGraduate School of Health Sciences, Okayama UniversityFumihiroMitsunobuGraduate School ofMedicine Dentistry and Pharmaceutical Sciences, Okayama UniversityHiroakiTeratoAdvanced Science Research Center Okayama UniversityKiyonoriYamaokaGraduate School of Health Sciences, Okayama UniversityRadon inhalation decreases the level of lipid peroxide (LPO); this is attributed to the activation of antioxidative functions. This activation contributes to the beneficial effects of radon therapy, but there are no studies on the risks of radon therapy, such as DNA damage. We evaluated the effect of radon inhalation on DNA damage caused by oxidative stress and explored the underlying mechanisms. Mice were exposed to radon inhalation at concentrations of 2 or 20 kBq/m(3) (for one, three, or 10 days). The 8-hydroxy-2 '-deoxyguanosine (8-OHdG) levels decreased in the brains of mice that inhaled 20 kBq/m(3) radon for three days and in the kidneys of mice that inhaled 2 or 20 kBq/m(3) radon for one, three or 10 days. The 8-OHdG levels in the small intestine decreased by approximately 20-40% (2 kBq/m(3) for three days or 20 kBq/m(3) for one, three or 10 days), but there were no significant differences in the 8-OHdG levels between mice that inhaled a sham treatment and those that inhaled radon. There was no significant change in the levels of 8-oxoguanine DNA glycosylase, which plays an important role in DNA repair. However, the level of Mn-superoxide dismutase (SOD) increased by 15-60% and 15-45% in the small intestine and kidney, respectively, following radon inhalation. These results suggest that Mn-SOD probably plays an important role in the inhibition of oxidative DNA damage.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2409-9279332020Metastasis Model of Cancer Stem Cell-Derived Tumors60ENHagerMansourDepartment of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama UniversityGhmkinHassanLaboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversitySaid M.AfifyLaboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityTingYanDepartment of Pathology, Shanxi Key Laboratory of Carcinogenesis and Translational Research on Esophageal Cancer, Shanxi Medical UniversityAkimasaSenoDepartment of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama UniversityMasaharuSenoDepartment of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama UniversityMetastasis includes the dissemination of cancer cells from a malignant tumor and seed in distant sites inside the body forming secondary tumors. Metastatic cells from the primary tumor can move even before the cancer is detected. Therefore, metastases are responsible for more than 90% of cancer-related deaths. Over recent decades there has been adequate evidence suggesting the existence of CSCs with self-renewing and drug-resistant potency within heterogeneous tumors. Cancer stem cells (CSCs) act as a tumor initiating cells and have roles in tumor retrieve and metastasis. Our group recently developed a unique CSC model from mouse induced pluripotent stem cells cultured in the presence of cancer cell-conditioned medium that mimics tumors microenvironment. Using this model, we demonstrated a new method for studying metastasis by intraperitoneal transplantation of tumors and investigate the metastasis ability of cells from these segments. First of all, CSCs were injected subcutaneously in nude mice. The developed malignant tumors were minimized then transplanted into the peritoneal cavity. Following this, the developed tumor in addition to lung, pancreas and liver were then excised and analyzed. Our method showed the metastatic potential of CSCs with the ability of disseminated and moving to blood circulation and seeding in distant organs such as lung and pancreas. This method could provide a good model to study the mechanisms of metastasis according to CSC theory.No potential conflict of interest relevant to this article was reported.Springer International Publishing AGActa Medica Okayama2523-39633102021Temperature-dependent device properties of gamma-CuI and beta-Ga2O3 heterojunctions796ENRama Venkata KrishnaRaoGraduate School of Natural Science and Technology, Okayama UniversityAjinkya K.RanadeDepartment of Physical Science and Engineering, Nagoya Institute of TechnologyPradeepDesaiDepartment of Physical Science and Engineering, Nagoya Institute of TechnologyGolapKalitaDepartment of Physical Science and Engineering, Nagoya Institute of TechnologyHirooSuzukiGraduate School of Natural Science and Technology, Okayama UniversityYasuhikoHayashiGraduate School of Natural Science and Technology, Okayama UniversityTemperature-dependent studies of Ga2O3-based heterojunction devices are important in understanding its carrier transport mechanism, junction barrier potential, and stability at higher temperatures. In this study, we investigated the temperature-dependent device characteristics of the p-type gamma-copper iodide (gamma-CuI)/n-type beta-gallium oxide (beta-Ga2O3) heterojunctions, thereby revealing their interface properties. The fabricated gamma-CuI/beta-Ga2O3 heterojunction showed excellent diode characteristics with a high rectification ratio and low reverse saturation current at 298 K in the presence of a large barrier height (0.632 eV). The temperature-dependent device characteristics were studied in the temperature range 273-473 K to investigate the heterojunction interface. With an increase in temperature, a gradual decrease in the ideality factor and an increase in the barrier height were observed, indicating barrier inhomogeneity at the heterojunction interface. Furthermore, the current-voltage measurement showed electrical hysteresis for the reverse saturation current, although it was not observed for the forward bias current. The presence of electrical hysteresis for the reverse saturation current and of the barrier inhomogeneity in the temperature-dependent characteristics indicates the presence of some level of interface states for the gamma-CuI/beta-Ga2O3 heterojunction device. Thus, our study showed that the electrical hysteresis can be correlated with temperature-dependent electrical characteristics of the beta-Ga2O3-based heterojunction device, which signifies the presence of surface defects and interface states.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2076-08251082021Fabrication of a Polyimide Film Pneumatic Actuator by Molding and Welding Processes177ENDaisukeYamaguchiInstitute of Academic and Research, Okayama UniversityTatsuyaHanakiDepartment of Mechanical Engineering, Saitama UniversityYujiIshinoDepartment of Mechanical Engineering, Saitama UniversityMasayaTakasakiDepartment of Mechanical Engineering, Saitama UniversityTakeshiMizunoDepartment of Mechanical Engineering, Saitama UniversityThe bellows pneumatic actuator, which is made by folding a non-stretch film, has been proposed for various applications because it is easy to fabricate and is extremely thin and light. However, it has subpar durability performance, especially in the folded part of the film. In this study, we propose an actuator with a pod structure that possesses high design flexibility and is free from folding. A method of molding a pod structure on a polyimide film was established and a pneumatic actuator was successfully fabricated by using PI films. Two types of PI film pneumatic actuators with the same curvature, bellows type, and pod type were fabricated. Both were confirmed to have equivalent output characteristics. The bending angle and generated torque of the pod-structure actuator were 34 degrees and 3.3 mNm, respectively. In addition, the pod structure has approximately twice the durability of the bellows structure. By using the fabrication method proposed in this paper, it is possible to realize an air chamber (i.e., an actuator) that has both high durability and bending motion.No potential conflict of interest relevant to this article was reported.Nature ResearchActa Medica Okayama2041-17231212021Ultrafast olivine-ringwoodite transformation during shock compression4305ENTakuoOkuchiInstitute for Integrated Radiation and Nuclear Science, Kyoto UniversityYusukeSetoGraduate School of Science, Kobe UniversityNaotakaTomiokaKochi Institute for Core Sample Research, Japan Agency for Marine-Earth Science and Technology (JAMSTEC)TakeshiMatsuokaInstitute for Open and Transdisciplinary Research Initiatives, Osaka UniversityBrunoAlbertazziGraduate School of Engineering, Osaka UniversityNicholas J.HartleyGraduate School of Engineering, Osaka UniversityYuichiInubushiJapan Synchrotron Radiation Research Institute,KentoKatagiriGraduate School of Engineering, Osaka UniversityRyosukeKodamaGraduate School of Engineering, Osaka UniversityTatiana A.PikuzGraduate School of Engineering, Osaka UniversityNarangooPurevjavInstitute for Planetary Materials, Okayama UniversityKoheiMiyanishiRIKEN SPring-8 CenterTomokoSatoGraduate School of Science, Hiroshima UniversityToshimoriSekineGraduate School of Engineering, Osaka UniversityKeiichiSuedaRIKEN SPring-8 CenterKazuo A.TanakaGraduate School of Engineering, Osaka UniversityYoshinoriTangeJapan Synchrotron Radiation Research InstituteTadashiTogashiJapan Synchrotron Radiation Research InstituteYuheiUmedaInstitute for Integrated Radiation and Nuclear Science, Kyoto UniversityToshinoriYabuuchiJapan Synchrotron Radiation Research InstituteMakinaYabashiJapan Synchrotron Radiation Research InstituteNorimasaOzakiGraduate School of Engineering, Osaka UniversityMeteorites from interplanetary space often include high-pressure polymorphs of their constituent minerals, which provide records of past hypervelocity collisions. These collisions were expected to occur between kilometre-sized asteroids, generating transient high-pressure states lasting for several seconds to facilitate mineral transformations across the relevant phase boundaries. However, their mechanisms in such a short timescale were never experimentally evaluated and remained speculative. Here, we show a nanosecond transformation mechanism yielding ringwoodite, which is the most typical high-pressure mineral in meteorites. An olivine crystal was shock-compressed by a focused high-power laser pulse, and the transformation was time-resolved by femtosecond diffractometry using an X-ray free electron laser. Our results show the formation of ringwoodite through a faster, diffusionless process, suggesting that ringwoodite can form from collisions between much smaller bodies, such as metre to submetre-sized asteroids, at common relative velocities. Even nominally unshocked meteorites could therefore contain signatures of high-pressure states from past collisions. No potential conflict of interest relevant to this article was reported.MDPI AGActa Medica Okayama1424-82471472021The Effect of Cyanine Dye NK-4 on Photoreceptor Degeneration in a Rat Model of Early-Stage Retinitis Pigmentosa694ENShihuiLiuDepartment of Ophthalmology, Okayama University Graduate School of Interdisciplinary Science and Engineering in Health SystemsToshihikoMatsuoDepartment of Ophthalmology, Okayama University Graduate School of Interdisciplinary Science and Engineering in Health SystemsMaryMiyajiDepartment of Medical Neurobiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesOsamuHosoyaDepartment of Medical Neurobiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesThe present study aimed to evaluate the effects of NK-4 on the apoptosis of photoreceptors in a rat model of retinitis pigmentosa and explore the mechanism underlying anti-apoptosis activity. The Royal College of Surgeons (RCS) rats received an intravitreous injection of NK-4 solution in the left eye and vehicle control in the right eye. Apoptosis was detected by TUNEL method in frozen sections of the eyes. The retinal tissues of the rats were dissected for RNA-seq analysis. Functional and pathway enrichment analyses of differentially expressed genes (DEGs) were performed by using Metascape and DAVID software. The expression levels of DEGs were confirmed by real-time quantitative PCR (RT-qPCR). The number of apoptotic cells decreased in the outer nuclear layer (ONL) and the thickness of the ONL was significantly thicker in the retina of NK-4-injected eyes, compared with control eyes. Five DEGs were identified by RNA-seq analysis, and Hmox1, Mt1, Atf5, Slc7a11, and Bdh2 were confirmed to be up-regulated by RT-qPCR. Functional and pathway enrichment analysis of the up-regulated genes showed that anti-apoptosis effects of NK-4 in the retina of RCS rats may be related to the pathways of metal ion homeostasis, negative regulation of neuron death, response to toxic substance, and pigment metabolic process. We found a potential mechanism of NK-4, providing a new viewpoint for the development of more therapeutic uses of NK-4 in the future.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama1422-006722132021Citric Acid-Mediated Abiotic Stress Tolerance in Plants7235ENMd.Tahjib-Ul-ArifGraduate School of Environmental and Life Science, Okayama UniversityMst, IshratZahanPlant Breeding Division, Bangladesh Rice Research InstituteMd. MasudulKarimDepartment of Crop Botany, Bangladesh Agricultural UniversityShahinImranDepartment of Agronomy, Khulna Agricultural UniversityCharles T.HunterChemistry Research Unit, United States Department of Agriculture—Agricultural Research ServiceMd. SaifulIslamDepartment of Fisheries, Bangamata Sheikh Fojilatunnesa Mujib Science and Technology UniversityMd. AshikMiaDepartment of Crop Botany, Bangladesh Agricultural UniversityMd. AbdulHannanDepartment of Biochemistry and Molecular Biology, Bangladesh Agricultural UniversityMohammad SaidurRhamanDepartment of Seed Science and Technology, Bangladesh Agricultural UniversityMd. AfzalHossainDepartment of Biochemistry and Molecular Biology, Bangladesh Agricultural UniversityMarianBresticDepartment of Plant Physiology, Slovak University of AgricultureMilanSkalickyDepartment of Botany and Plant Physiology, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences PragueYoshiyukiMurataGraduate School of Environmental and Life Science, Okayama UniversitySeveral recent studies have shown that citric acid/citrate (CA) can confer abiotic stress tolerance to plants. Exogenous CA application leads to improved growth and yield in crop plants under various abiotic stress conditions. Improved physiological outcomes are associated with higher photosynthetic rates, reduced reactive oxygen species, and better osmoregulation. Application of CA also induces antioxidant defense systems, promotes increased chlorophyll content, and affects secondary metabolism to limit plant growth restrictions under stress. In particular, CA has a major impact on relieving heavy metal stress by promoting precipitation, chelation, and sequestration of metal ions. This review summarizes the mechanisms that mediate CA-regulated changes in plants, primarily CA's involvement in the control of physiological and molecular processes in plants under abiotic stress conditions. We also review genetic engineering strategies for CA-mediated abiotic stress tolerance. Finally, we propose a model to explain how CA's position in complex metabolic networks involving the biosynthesis of phytohormones, amino acids, signaling molecules, and other secondary metabolites could explain some of its abiotic stress-ameliorating properties. This review summarizes our current understanding of CA-mediated abiotic stress tolerance and highlights areas where additional research is needed.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2073-89941352021Asymmetry of Authority or Information Underlying Insufficient Communication Associated with a Risk of Crashes or Incidents in Passenger Railway Transportation803ENAtsuoMurataDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversityWaldemarKarwowskiDepartment of Industrial Engineering and Management Systems, University of Central FloridaSimilar crashes or incidents may recur as a result of insufficient communication in uncertain and risky situations that potentially threaten safety. The common root causes of insufficient communication across a series of incidents and crashes must be explored in detail to prevent a vicious circle of similar incidents or crashes from occurring. This study summarizes a series of incidents and crashes (derailment due to excessive train speed) at JR West at the West Japan Railway Company (JR West) that are considered to have arisen from insufficient communication. The incidents included (i) resuming train service without confirming the number of passengers on board and leaving passengers behind the station at Higashi-Hiroshima station, (ii) continuing train service in spite of an apparent risk of a crash detected at Okayama station, and (iii) leaving the crack of the train hood as it was at Kokura station. We discuss the causes of insufficient communication (particularly in relation to the sharing of information) among the three branches of staff-the station staff, the conductor and train driver, and the train operation management center-that led to the incidents or crashes. Two factors contributed to the insufficient communication in the series of incidents and crashes: (a) Asymmetry of authority, which hinders the discussion of issues openly and equally among the branches concerned. (b) An unacceptable level of knowledge or information for all branches concerned.No potential conflict of interest relevant to this article was reported.IOP PublishingActa Medica Okayama1741-25601842021Modelling the visual response to an OUReP retinal prosthesis with photoelectric dye coupled to polyethylene film045006ENKoichiroYamashitaGraduate School of Natural Science and Technology, Okayama UniversityPrathimaSundaramDepartment of Electrical and Computer Engineering, University of TorontoTetsuyaUchidaGraduate School of Natural Science and Technology, Okayama UniversityToshihikoMatsuoGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityWillyWongDepartment of Electrical and Computer Engineering, University of TorontoObjective. Retinal prostheses have been developed to restore vision in blind patients suffering from diseases like retinitis pigmentosa. Approach. A new type of retinal prosthesis called the Okayama University-type retinal prosthesis (OUReP) was developed by chemically coupling photoelectric dyes to a polyethylene film surface. The prosthesis works by passively generating an electric potential when stimulated by light. However, the neurophysiological mechanism of how OUReP stimulates the degenerated retina is unknown. Main results. Here, we explore how the OUReP affects retinal tissues using a finite element model to solve for the potential inside the tissue and an active Hodgkin-Huxley model based on rat vision to predict the corresponding retinal bipolar response. Significance. We show that the OUReP is likely capable of eliciting responses in retinal bipolar cells necessary to generate vision under most ambient conditions.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama1422-00672292021Inhibition of HSF1 and SAFB Granule Formation Enhances Apoptosis Induced by Heat Stress4982ENKazunoriWatanabeGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityTakashiOhtsukiGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityStress resistance mechanisms include upregulation of heat shock proteins (HSPs) and formation of granules. Stress-induced granules are classified into stress granules and nuclear stress bodies (nSBs). The present study examined the involvement of nSB formation in thermal resistance. We used chemical compounds that inhibit heat shock transcription factor 1 (HSF1) and scaffold attachment factor B (SAFB) granule formation and determined their effect on granule formation and HSP expression in HeLa cells. We found that formation of HSF1 and SAFB granules was inhibited by 2,5-hexanediol. We also found that suppression of HSF1 and SAFB granule formation enhanced heat stress-induced apoptosis. In addition, the upregulation of HSP27 and HSP70 during heat stress recovery was suppressed by 2,5-hexanediol. Our results suggested that the formation of HSF1 and SAFB granules was likely to be involved in the upregulation of HSP27 and HSP70 during heat stress recovery. Thus, the formation of HSF1 and SAFB granules was involved in thermal resistance.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2072-669413102021Cripto-1 as a Potential Target of Cancer Stem Cells for Immunotherapy2491ENHirokoIshiiGSP Enterprise, Inc.Said M.AfifyLaboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityGhmkinHassanLaboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityDavid S.SalomonMouse Cancer Genetics Program, Center for Cancer Research, National Cancer InstituteMasaharuSenoSimple Summary Cancer immunotherapy is gaining attention as a potential fourth treatment following surgery, chemotherapy, and radiation therapy. Cancer stem cells have recently been recognized and validated as a key target for cancer treatment. Cripto-1, which is a GPI-anchored membrane-bound protein that functions as a co-receptor of Nodal, is a marker of cancer stem cells. Since Nodal is a member of the TGF-beta family, which performs an important role in stem cells and cancer stem cells, the inhibition of Cripto-1 could be a strategy by which to block Nodal signaling and thereby suppress cancer stem cells. We propose that Cripto-1 may be a novel target for cancer immunotherapy. The immune system has been found to be suppressed in cancer patients. Cancer cells are extremely resistant to chemotherapeutic drugs, conventional immunotherapy, or cancer antigen vaccine therapy. Cancer immunotherapy, which is mainly based on immune checkpoint inhibitors, such as those for PD-1, PD-L1, and CTLA4, is an effective treatment method. However, no immunotherapeutic target has been found that retains validity in the face of tumor diversity. The transforming growth factor (TGF)-beta cytokine family possesses broad biological activity and is involved in the induction and/or transdifferentiation of helper T cells, which are important in immunotherapy. Nodal is a member of the TGF-beta family playing important roles in tissue stem cells and cancer stem cells (CSCs), interacting with the co-receptor Cripto-1, as well as with Activin type IB (Alk4) and Activin typeIIreceptors, and maintaining stemness and Notch and Wnt/beta-catenin signaling in CSCs. In recent years, it has been reported that Cripto-1 could be a potential therapeutic target in CSCs. Here, we review the accumulated literature on the molecular mechanisms by which Cripto-1 functions in CSCs and discuss the potential of Cripto-1 as an immunotherapeutic target in CSCs.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2227-9059952021Paclitaxel-Based Chemotherapy Targeting Cancer Stem Cells from Mono- to Combination Therapy500ENHend M.NawaraDepartment of Biotechnology and Drug Discovery, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversitySaid M.AfifyDepartment of Biotechnology and Drug Discovery, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityGhmkinHassanDepartment of Biotechnology and Drug Discovery, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityMaram H.ZahraDepartment of Biotechnology and Drug Discovery, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityAkimasaSenoDepartment of Biotechnology and Drug Discovery, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityMasaharuSenoDepartment of Biotechnology and Drug Discovery, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityPaclitaxel (PTX) is a chemotherapeutical agent commonly used to treat several kinds of cancer. PTX is known as a microtubule-targeting agent with a primary molecular mechanism that disrupts the dynamics of microtubules and induces mitotic arrest and cell death. Simultaneously, other mechanisms have been evaluated in many studies. Since the anticancer activity of PTX was discovered, it has been used to treat many cancer patients and has become one of the most extensively used anticancer drugs. Regrettably, the resistance of cancer to PTX is considered an extensive obstacle in clinical applications and is one of the major causes of death correlated with treatment failure. Therefore, the combination of PTX with other drugs could lead to efficient therapeutic strategies. Here, we summarize the mechanisms of PTX, and the current studies focusing on PTX and review promising combinations.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama1996-19441482021Design and Mechanical Compatibility of Nylon Bionic Cancellous Bone Fabricated by Selective Laser Sintering1965ENXuewenChenSchool of Materials Science and Engineering, Henan University of Science and TechnologyTingtingLianSchool of Materials Science and Engineering, Henan University of Science and TechnologyBoZhangSchool of Materials Science and Engineering, Henan University of Science and TechnologyYuqingDuSchool of Materials Science and Engineering, Henan University of Science and TechnologyKexueDuSchool of Materials Science and Engineering, Henan University of Science and TechnologyNanXiangSchool of Materials Science and Engineering, Henan University of Science and TechnologyDong-WonJungFaculty of Mechanical, Jeju National UniversityGuangxinWangSchool of Materials Science and Engineering, Henan University of Science and TechnologyAkiyoshiOsakaInstitute of Engineering, Okayama UniversityIn order to avoid the stress shielding phenomenon in orthopedic bionic bone implantation, it is necessary to consider the design of mechanical compatible implants imitating the host bone. In this study, we developed a novel cancellous bone structure design method aimed at ensuring the mechanical compatibility between the bionic bone and human bone by means of computer-aided design (CAD) and finite element analysis technology (specifically, finite element modeling (FEM)). An orthogonal lattice model with volume porosity between 59% and 96% was developed by means of CAD. The effective equivalent elastic modulus of a honeycomb structure with square holes was studied by FEM simulation. With the purpose of verifying the validity of the cancellous bone structure design method, the honeycomb structure was fabricated by selective laser sintering (SLS) and the actual equivalent elastic modulus of the honeycomb structure was measured with a uniaxial compression test. The experimental results were compared with the FEM values and the predicted values. The results showed that the stiffness values of the designed structures were within the acceptable range of human cancellous bone of 50-500 MPa, which was similar to the stiffness values of human vertebrae L1 and L5. From the point of view of mechanical strength, the established cellular model can effectively match the elastic modulus of human vertebrae cancellous bone. The functional relationship between the volume porosity of the nylon square-pore honeycomb structure ranging from 59% to 96% and the effective elastic modulus was established. The effect of structural changes related to the manufacture of honeycomb structures on the equivalent elastic modulus of honeycomb structures was studied quantitatively by finite element modeling.No potential conflict of interest relevant to this article was reported.ASME InternationalActa Medica Okayama0094-993014322020Prediction of the Fracture Location by Tensile Tests of Gray Cast Iron Based on the Dimensional Changes of Graphite Flakes021502ENNaoyaTadaGraduate School of Natural Science and Technology, Okayama UniversityTakeshiUemoriGraduate School of Natural Science and Technology, Okayama UniversityJunjiSakamotoGraduate School of Natural Science and Technology, Okayama UniversityGray cast iron has been used as a component in various mechanical parts, such as the blocks and heads of automobile and marine engines, cylinder liners for internal combustion engines, and machine tool bases. It is desirable because of its good castability and machinability, damping characteristics, and high performance-to-cost ratio. On the other hand, weak graphite flakes present in gray cast iron serve as stress concentrators and adversely affect the material strength. Therefore, it is crucial to examine the relationship between the distribution of graphite flakes and the strength or fracture of gray cast iron. In this study, tensile tests on gray cast iron were carried out using a plate specimen and observed by scanning electron microscopy, and the microscopic deformation was observed on the specimen surface. Particularly, the change in the size of graphite flakes during the tensile tests was examined, and the observed trend was discussed. The experimental results reveal that the dimensional changes in the graphite flakes vary in the observed area and that the final fracture occurs in an area where a large dimensional change is observed, suggesting that the fracture location or critical parts of gray cast iron can be predicted from the dimensional changes of the graphite flakes at an early stage of deformation.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X7522021Histological Analysis of Repaired Tissue after Pullout Repair of a Medial Meniscus Posterior Root Tear225230ENHaoweiXueDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesTakayukiFurumatsuDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesYuki OkazakiDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesTakaakiHiranakaDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesKeisuke KintakaDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesXimingZhangDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesAkiYoshidaDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesToshifumiOzakiDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesCase Report/10.18926/AMO/61905A 65-year-old man presented with a left medial meniscus (MM) posterior root tear (PRT). Unicompartmental knee arthroplasty was performed 12 months after transtibial pullout repair of the MMPRT. Repaired MM posterior root tissue was subjected to histological analysis. Immunostaining and picrosirius red staining showed sufficient deposition of type I collagen, and hematoxylin-eosin staining using a polarized microscope showed well-aligned fiber orientation in the repaired tissue. The repaired posterior root (post-transtibial pullout repair) showed mature and well-aligned ligament-like tissue. Preserving the MM posterior root remnant to mimic the original posterior root tissue might be useful when performing pullout repair.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2073-89941332021On the Root Causes of the Fukushima Daiichi Disaster from the Perspective of High Complexity and Tight Coupling in Large-Scale Systems414ENAtsuoMurataDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversityWaldemarKarwowskiDepartment of Industrial Engineering and Management Systems, University of Central FloridaThis study explores the root causes of the Fukushima Daiichi disaster and discusses how the complexity and tight coupling in large-scale systems should be reduced under emergencies such as station blackout (SBO) to prevent future disasters. First, on the basis of a summary of the published literature on the Fukushima Daiichi disaster, we found that the direct causes (i.e., malfunctions and problems) included overlooking the loss of coolant and the nuclear reactor's failure to cool down. Second, we verified that two characteristics proposed in "normal accident" theory-high complexity and tight coupling-underlay each of the direct causes. These two characteristics were found to have made emergency management more challenging. We discuss how such disasters in large-scale systems with high complexity and tight coupling could be prevented through an organizational and managerial approach that can remove asymmetry of authority and information and foster a climate of openly discussing critical safety issues in nuclear power plants.No potential conflict of interest relevant to this article was reported.ElsevierActa Medica Okayama1044579X2021Cooperation between NRF2-mediated transcription and MDIG-dependent epigenetic modifications in arsenic-induced carcinogenesis and cancer stem cellsENZhuoyueBiDepartment of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State UniversityQianZhangDepartment of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State UniversityYaoFuDepartment of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State UniversityAkimasaSenoFaculty of Engineering, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityPriyaWadgaonkarDepartment of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State UniversityYiranQiuDepartment of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State UniversityBandarAlmutairyDepartment of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State UniversityLipingXuDepartment of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State UniversityWenxuanZhangDepartment of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State UniversityChitraThakurDepartment of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State UniversityFeiChenDepartment of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University Environmental exposure to arsenic, a well-established carcinogen linked to a number of human cancers, is a public health concern in many areas of the world. Despite extensive studies on the molecular mechanisms of arsenic-induced carcinogenesis, how initial cellular responses, such as activation of stress kinases and the generation of reactive oxygen species, converge to affect the transcriptional and/or epigenetic reprogramming required for the malignant transformation of normal cells or normal stem cells remains to be elucidated. In this review, we discuss some recent discoveries showing how the transcription factor NRF2 and an epigenetic regulator, MDIG, contribute to the arsenic-induced generation of cancer stem-like cells (CSCs) as determined by applying CRISPR-Cas9 gene editing and chromosome immunoprecipitation followed by DNA sequencing (ChIP-seq).No potential conflict of interest relevant to this article was reported.ElsevierActa Medica Okayama0921-50938072021Effects of microstructural characteristics on the hydrogen embrittlement characteristics of austenitic, ferritic, and γ–α duplex stainless steels140851ENMitsuhiroOkayasuGraduate School of Natural Science and Technology, Okayama UniversityTakafumiFujiwaraGraduate School of Natural Science and Technology, Okayama UniversityHydrogen embrittlement (HE) characteristics of γ (AS), α (FS), and γ–α duplex (DS) stainless steels were examined experimentally and numerically. Severe HE occurred in the DS sample, whereas weak HE was detected in the AS and FS samples. This was attributed to the high hydrogen concentrations at the DS-trapping sites. Hydrogen trapping occurred in the low atomic density zones in the boundaries between α and γ phases in DS sample. The chemical bonding between atomic-scale phase boundaries was weakened by hydrogen penetration. This resulted in a crack growth along the DS α/γ phase boundaries. The ductility of DS decreased as the hydrogen content increased, especially when it exceeded 15 ppm. In contrast, the weak HE observed among AS and FS samples was attributed to the small hydrogen levels that infiltrated both samples. Finally, HE mechanism was proposed on the basis of these experimental results.No potential conflict of interest relevant to this article was reported.e-Century PublishingActa Medica Okayama2156-69761122021Isolation and characterization of cancer stem cells derived from human glioblastoma441457ENHirokoIshiiGSP Enterprise, Inc.YukiMimuraLaboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityMaram H.ZahraLaboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityShotaKatayamaLaboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityGhmkinHassanLaboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversitySaid M.AfifyLaboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityMasaharuSenoLaboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityCancer stem cell (CSC) is considered as a cause of cancer recurrence and metastasis. Simultaneously CSCs are responsible for the heterogeneous population in tumor tissues due to their differentiation potential. However, the characterizations of CSCs are still not enough and cancer stem cell lines widely available is desired to be established for the advancement of cancer research. In this study, we tried to isolate and characterize stem like cells from human glioblastoma cell line U-251MG cells. U-251MG P1 cells, which was previously condensed in the presence of hyaluronic acid as CD44 positive population were subjected to single cell isolation procedure. Although 5 clones were isolated, only one clone exhibited high expression of CD44, Nanog, OCT3/4 and SOX2, and named U-251MGSC1. The sphere forming ability of U-251MGSC1 cell was significantly higher than the parental U-251MG cells. Tumorigenicity of U-251MG-SC1 cells were higher than that of U-251MG cells. U-251MGSC1 cells exhibited higher expression of CD44, SOX2, Nestin and A2B5 than U-251MG cells in vitro and in vivo. The expression of GFAP and NF-M was enhanced when the cells were treated with the conditioned medium of U-251MG cells indicating the potential of differentiation. Sphere forming ability was more efficient than that of U-251MG cells and was enhanced in the presence of hyaluronic acid, which enhanced the cell growth as well. U-251MGSC1 cells exhibited rapid growth tumor in nude mice and efficient metastatic ability in transmembrane assay when compared with U-251MG cells. As the result, we concluded U-251MGSC1 cell was a glioblastoma CSC line derived from the parental U-251MG cells. U-251MGSC1 cells will be a good tool to develop effective therapeutic agents against CSCs and to elucidate the properties of glioma derived CSCs and the mechanism of tumor development in brain.No potential conflict of interest relevant to this article was reported.Institute of Electrical and Electronics EngineersActa Medica Okayama2169-353692021Development of an Eye-Gaze Input System With High Speed and Accuracy through Target Prediction Based on Homing Eye Movements2268822697ENAtsuoMurataDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversityToshihisaDoiDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversityKazushiKageyamaDepartment of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama UniversityWaldemarKarwowskiEngineering and Management Systems, University of Central FloridaIn this study, a method to predict a target on the basis of the trajectory of eye movements and to increase the pointing speed while maintaining high predictive accuracy is proposed. First, a predictive method based on ballistic (fast) eye movements (Approach 1) was evaluated in terms of pointing speed and predictive accuracy. In Approach 1, the so-called Midas touch problem (pointing to an unintended target) occurred, particularly when a small number of samples was used to predict a target. Therefore, to overcome the poor predictive accuracy of Approach 1, we developed a new predictive method (Approach 2) using homing (slow) eye movements rather than ballistic (fast) eye movements. Approach 2 overcame the disadvantage (inaccurate prediction) of Approach 1 by shortening the pointing time while maintaining high predictive accuracy.No potential conflict of interest relevant to this article was reported.SpringerActa Medica Okayama1615-5262202021Web access monitoring mechanism via Android WebView for threat analysis833847ENYutaImamuraGraduate School of Natural Science and Technology, Okayama UniversityRintaroOritoGraduate School of Natural Science and Technology, Okayama UniversityHiroyukiUekawaGraduate School of Natural Science and Technology, Okayama UniversityKritsanaChaikaewFaculty of Engineering, Kasetsart UniversityPattaraLeelapruteFaculty of Engineering, Kasetsart UniversityMasayaSatoGraduate School of Natural Science and TechnologyToshihiroYamauchiGraduate School of Natural Science and Technology, Okayama UniversityMany Android apps employ WebView, a component that enables the display of web content in the apps without redirecting users to web browser apps. However, WebView might also be used for cyberattacks. Moreover, to the best of our knowledge, although some countermeasures based on access control have been reported for attacks exploiting WebView, no mechanism for monitoring web access via WebView has been proposed and no analysis results focusing on web access via WebView are available. In consideration of this limitation, we propose a web access monitoring mechanism for Android WebView to analyze web access via WebView and clarify attacks exploiting WebView. In this paper, we present the design and implementation of this mechanism by modifying Chromium WebView without any modifications to the Android framework or Linux kernel. The evaluation results of the performance achieved on introducing the proposed mechanism are also presented here. Moreover, the result of threat analysis of displaying a fake virus alert while browsing websites on Android is discussed to demonstrate the effectiveness of the proposed mechanism.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama1420-30492612020Photoinduced Endosomal Escape Mechanism: A View from Photochemical Internalization Mediated by CPP-Photosensitizer Conjugates36ENTet HtutSoeDepartment of Biotechnology, Mandalay Technological UniversityKazunoriWatanabeDepartment of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityTakashiOhtsukiDepartment of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityEndosomal escape in cell-penetrating peptide (CPP)-based drug/macromolecule delivery systems is frequently insufficient. The CPP-fused molecules tend to remain trapped inside endosomes and end up being degraded rather than delivered into the cytosol. One of the methods for endosomal escape of CPP-fused molecules is photochemical internalization (PCI), which is based on the use of light and a photosensitizer and relies on photoinduced endosomal membrane destabilization to release the cargo molecule. Currently, it remains unclear how this delivery strategy behaves after photostimulation. Recent findings, including our studies using CPP-cargo-photosensitizer conjugates, have shed light on the photoinduced endosomal escape mechanism. In this review, we discuss the structural design of CPP-photosensitizer and CPP-cargo-photosensitizer conjugates, and the PCI mechanism underlying their application.No potential conflict of interest relevant to this article was reported.WileyActa Medica Okayama2196-7350792020Titanium as an Instant Adhesive for Biological Soft Tissue1902089ENMasahiroOkadaDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityEmilio SatoshiHaraDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversitytsushiYabeDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityKeiOkadaDepartment of Applied Chemistry and Biotechnology, Faculty of Engineering, Okayama UniversityYoShibataDepartment of Conservative Dentistry, Division of Biomaterials and Engineering, Showa University School of DentistryYasuhiroTorii Department of Comprehensive Dentistry, Okayama University HospitalTakayoshiNakanoDivision of Materials and Manufacturing Science, Graduate School of Engineering, Osaka UniversityTakuyaMatsumotoDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityA variety of polymer‐ and ceramic‐based soft‐tissue adhesives have been developed as alternatives to surgical sutures, yet several disadvantages regarding the mechanical properties, biocompatibility, and handling hinder their further application particularly when applied for immobilization of implantable devices. Here, it is reported that a biocompatible and tough metal, titanium (Ti), shows instant and remarkable adhesion properties after acid treatment, demonstrated by ex vivo shear adhesion tests with mouse dermal tissues. Importantly, in vivo experiments demonstrate that the acid‐treated Ti can easily and stably immobilize a device implanted in the mouse subcutaneous tissue. Collectively, the acid‐treated Ti is shown as a solid‐state instant adhesive material for biological soft tissues, which can have diverse applications including immobilization of body‐implantable devices.No potential conflict of interest relevant to this article was reported.Springer NatureActa Medica Okayama0007-092012292020A novel model of liver cancer stem cells developed from induced pluripotent stem cells13781390ENSaid M.AfifyDepartment of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama UniversityAnna SanchezCalleDivision of Molecular and Cellular Medicine, National Cancer Center Research InstituteGhmkinHassanLaboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityKazukiKumonDepartment of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama UniversityHend M.NawaraDepartment of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama UniversityMaram H.ZahraLaboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityHager M.MansourDepartment of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama UniversityApriliana CahyaKhayraniDepartment of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama UniversityMd JahangirAlamDepartment of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama UniversityJuanDuDepartment of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama UniversityAkimasaSenoOkayama University Research Laboratory of Stem Cell Engineering in Detroit, IBio, Wayne State UniversityYoshiakiIwasakiDepartment of Gastroenterology and Hepatology, Graduate School of Medicine, Okayama UniversityMasaharuSenoDepartment of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama UniversityBackground</br>
Liver cancer is the second most common cause of cancer-related death. Every type of tumours including liver cancer contains cancer stem cells (CSCs). To date, the molecular mechanism regulating the development of liver CSCs remains unknown.</br>
Methods</br>
In this study, we tried to generate a new model of liver CSCs by converting mouse induced pluripotent stem cells (miPSCs) with hepatocellular carcinoma (HCC) cell line Huh7 cells conditioned medium (CM). miPSCs treated with CM were injected into the liver of BALB/c nude mice. The developed tumours were then excised and analysed.</br>
Results</br>
The primary cultured cells from the malignant tumour possessed self-renewal capacity, differentiation potential and tumorigenicity in vivo, which were found rich in liver cancer-associated markers as well as CSC markers.</br>
Conclusions</br>
We established a model of liver CSCs converting from miPS and showed different stages of stemness during conversion process. Our CSC model will be important to assess the molecular mechanisms necessary to develop liver CSCs and could help in defeating liver cancer.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama1996-194413222020Micro-Architectural Investigation of Teleost Fish Rib Inducing Pliant Mechanical Property5099ENYu YangJiaoDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityMasahiroOkadaDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityEmilio SatoshiHaraDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityShi ChaoXieDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityNoriyukiNagaokaAdvanced Research Center for Oral and Craniofacial Sciences, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityTakayoshiNakanoDivision of Materials and Manufacturing Science, Graduate School of Engineering, Osaka UniversityTakuyaMatsumotoDepartment of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityDespite the fact that various reports have been discussing bone tissue regeneration, precise bone tissue manipulation, such as controlling the physical properties of the regenerated bone tissue, still remains a big challenge. Here, we focused on the teleost fish ribs showing flexible and tough mechanical properties to obtain a deeper insight into the structural and functional features of bone tissue from different species, which would be valuable for the superior design of bone-mimicking materials. Herein, we examined their compositions, microstructure, histology, and mechanical properties. The first rib of Carassius langsdorfii showed a higher Young's modulus with a small region of chondrocyte clusters compared with other smaller ribs. In addition, highly oriented collagen fibers and osteocytes were observed in the first rib, indicating that the longest first rib would be more mature. Moreover, the layer-by-layer structure of the oriented bone collagen was observed in each rib. These microarchitectural and compositional findings of fish rib bone would give one the useful idea to reproduce such a highly flexible rib bone-like material.No potential conflict of interest relevant to this article was reported.ElsevierActa Medica Okayama2352-48476Suppl. 72020Self-assembly of Ni–Fe layered double hydroxide at room temperature for oxygen evolution reaction248254ENSeong HyunKimDepartment of Materials Science and Engineering, Pusan National UniversityYoo SeiParkDepartment of Materials Science and Engineering, Pusan National UniversityChihoKimDepartment of Materials Science and Engineering, Pusan National UniversityIl YeongKwonDepartment of Materials Science and Engineering, Pusan National UniversityJooyoungLeeMaterials Center for Energy Department, Surface Technology Division, Korea Institute of Materials Science,HyunsooJinDepartment of Mechanical Engineering, Worcester Polytechnic InstituteYoon-SeokLeeGraduate School of Natural Science and Technology, Okayama UniversitySung MookChoiMaterials Center for Energy Department, Surface Technology Division, Korea Institute of Materials ScienceYangdoKimDepartment of Materials Science and Engineering, Pusan National UniversityActive and stable electrocatalysts are the key to water electrolysis for hydrogen production. This paper reports a facile direct growth method to synthesize NiFe-layered double hydroxides (LDHs) on nickel foil as an electrocatalyst for the oxygen evolution reaction. The NiFe-LDH is synthesized by a galvanic process at room temperature without any additional energy for synthesis. The synthesized NiFe-LDH is a karst landform with abundant active sites and efficient mass diffusion. The NiFe-LDH with an oxygen defect show excellent electrocatalytic performance for the OER, with a low overpotential (272 mV at 10 mA/cm2), a small Tafel slope (43 mV/dec), and superior durability. Direct growth synthesis provide excellent electrical conductivity as well as strong bonding between the catalyst layer and the substrate. In addition, this synthesis process is simple to apply in the fabrication of a large size electrode and is believed to be applicable to commercialized alkaline water electrolysis.No potential conflict of interest relevant to this article was reported.ElsevierActa Medica Okayama2352-3964622020A detection method for latent circadian rhythm sleep-wake disorder103080ENMakotoAkashiThe Research Institute for Time Studies, Yamaguchi UniversityReimiSogawaDepartment of Clinical Genetics and Genomic Medicine, Okayama University HospitalRitsukoMatsumuraThe Research Institute for Time Studies, Yamaguchi UniversityAtsuhiroNishidaThe Research Institute for Time Studies, Yamaguchi UniversityRinoNakamuraThe Research Institute for Time Studies, Yamaguchi UniversityIsao T.TokudaDepartment of Mechanical Engineering, Ritsumeikan UniversityKoichiNodeDepartment of Cardiovascular Medicine, Saga UniversityBackground</br>
Individuals with typical circadian rhythm sleep-wake disorders (CRSWDs) have a habitual sleep timing that is desynchronized from social time schedules. However, it is possible to willfully force synchronisation against circadian-driven sleepiness, which causes other sleep problems. This pathology is distinguishable from typical CRSWDs and is referred to here as latent CRSWD (LCRSWD). Conventional diagnostic methods for typical CRSWDs are insufficient for detecting LCRSWD because sufferers have an apparently normal habitual sleep timing.</br>
Methods</br>
We first evaluated the reliability of circadian phase estimation based on clock gene expression using hair follicles collected at three time points without sleep interruption. Next, to identify detection criteria for LCRSWD, we compared circadian and sleep parameters according to estimated circadian phases, at the group and individual level, between subjects with low and high Pittsburgh Sleep Quality Index (PSQI) scores. To validate the reliability of identified detection criteria, we investigated whether the same subjects could be reproducibly identified at a later date and whether circadian amelioration resulted in sleep improvement.</br>
Findings</br>
We successfully validated the reliability of circadian phase estimation at three time points and identified potential detection criteria for individuals with LCRSWD attributed to delayed circadian-driven sleepiness. In particular, a criterion based on the interval between the times of the estimated circadian phase of clock gene expression and getting out of bed on work or school days was promising. We also successfully confirmed the reproducibility of candidate screening and sleep improvement by circadian amelioration, supporting the reliability of the detection criteria.</br>
Interpretation</br>
Although several limitations remain, our present study demonstrates a promising prototype of a detection method for LCRSWD attributed to delayed circadian-driven sleepiness. More extensive trials are needed to further validate this method.No potential conflict of interest relevant to this article was reported.NatureActa Medica Okayama2045-23221012020Mechanism underlying hippocampal long-term potentiation and depression based on competition between endocytosis and exocytosis of AMPA receptors14711ENTomonariSumiResearch Institute for Interdisciplinary Science, Okayama UniversityKoujiHaradaDepartment of Computer Science and Engineering, Toyohashi University of TechnologyN-methyl-D-aspartate (NMDA) receptor-dependent long-term potentiation (LTP) and long-term depression (LTD) of signal transmission form neural circuits and thus are thought to underlie learning and memory. These mechanisms are mediated by AMPA receptor (AMPAR) trafficking in postsynaptic neurons. However, the regulatory mechanism of bidirectional plasticity at excitatory synapses remains unclear. We present a network model of AMPAR trafficking for adult hippocampal pyramidal neurons, which reproduces both LTP and LTD. We show that the induction of both LTP and LTD is regulated by the competition between exocytosis and endocytosis of AMPARs, which are mediated by the calcium-sensors synaptotagmin 1/7 (Syt1/7) and protein interacting with C-kinase 1 (PICK1), respectively. Our result indicates that recycling endosomes containing AMPAR are always ready for Syt1/7-dependent exocytosis of AMPAR at peri-synaptic/synaptic membranes. This is because molecular motor myosin V-b constitutively transports the recycling endosome toward the membrane in a Ca2+-independent manner.No potential conflict of interest relevant to this article was reported.WileyActa Medica Okayama0008-40349912020Suspension pattern and rising height of sedimentary particles with low concentration in a mechanically stirred vessel410420ENYuichiroTokuraDepartment of Material and Energy Science, Graduate School of Environmental and Life Science, Okayama UniversityKeitaMiyagawaDepartment of Material and Energy Science, Graduate School of Environmental and Life Science, Okayama UniversityMd. AzharUddinDepartment of Material and Energy Science, Graduate School of Environmental and Life Science, Okayama UniversityYoshieiKatoDepartment of Material and Energy Science, Graduate School of Environmental and Life Science, Okayama UniversityIn this study, the effects of impeller rotation speed, off‐bottom clearance, blade angle, types of solid and liquid, etc., on the suspension pattern of sedimentary particles and particle rise height in liquid were investigated with a hemispherical vessel without baffles under low particle concentration. The transition conditions of suspension pattern between regimes I and II, and regimes II and III, were observed visually, and their non‐dimensional equations were expressed with an acceptable correlation by varying the above operation factors a great deal. Here, regime I is stagnation of particles on a vessel bottom, II is partial suspension, and III is complete suspension in liquid. The non‐dimensional equation of the maximum particle rise height was also successfully obtained. The combination of the non‐dimensional equations of transition and maximum particle rise height permitted us to determine the adequate solid/liquid mixing operation conditions without collision of particles with device parts.No potential conflict of interest relevant to this article was reported.NatureActa Medica Okayama2045-23221012020Three-dimensional observation and analysis of remineralization in dentinal caries lesions4387ENKumikoYoshiharaOkayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Department of Pathology & Experimental MedicineNoriyukiNagaokaOkayama University Dental School, Advanced Research Center for Oral and Craniofacial SciencesAkikoNakamuraNational Institute for Materials ScienceToruHaraNational Institute for Materials ScienceSatoshiHayakawaOkayama University, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Biomaterials LaboratoryYasuhiroYoshidaHokkaido University, Faculty of Dental Medicine, Department of Biomaterials and BioengineeringMeerbeek, BartVan MeerbeekKU Leuven (University of Leuven), Department of Oral Health Research, BIOMAT & UZ Leuven (University Hospitals Leuven)The remineralization mechanism in dental caries lesions is not completely understood. This study reports on ultrastructural and chemical changes observed within arrested caries lesions. Carious human teeth were observed using scanning electron microscopy (SEM) and focused-ion-beam (FIB)-SEM. The crystals detected in the caries lesions were characterized by transmission electron microscopy (TEM), along with chemical element mapping using energy-dispersive spectroscopy (EDS)-STEM. FIB-SEM 3D reconstructions revealed a severely damaged dentin surface abundantly covered by bacteria. Although the dentin tubules were clogged up to a depth of 100 mu m, bacterial invasion into dentin tubules was not observed. TEM crystal analysis and EDS-STEM revealed the presence of Ca and P, as well as of Mg within the HAp crystals deposited inside the dentin tubules. It was concluded that extensive remineralization with deposition of Mg-HAp crystals had occurred in dentin tubules of caries-arrested dentin. Understanding the natural remineralization process is thought to be helpful for developing clinical biomimetic remineralization protocols.No potential conflict of interest relevant to this article was reported.NatureActa Medica Okayama2045-23221012020Vectorial Proton Transport Mechanism of RxR, a Phylogenetically Distinct and Thermally Stable Microbial Rhodopsin282ENKeiichiKojimaFaculty of Pharmaceutical Sciences, Okayama UniversityTetsuyaUetaGraduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityTomoyasuNojiDepartment of Applied Chemistry, Graduate School of Engineering, The University of TokyoKeisukeSaitoDepartment of Applied Chemistry, Graduate School of Engineering, The University of TokyoKanaeKaneharaFaculty of Pharmaceutical Sciences, Okayama UniversitySusumuYoshizawaAtmosphere and Ocean Research Institute, The University of TokyoHiroshiIshikitaDepartment of Applied Chemistry, Graduate School of Engineering, The University of TokyoYukiSudoFaculty of Pharmaceutical Sciences, Okayama UniversityRubrobacter xylanophilus rhodopsin (RxR) is a phylogenetically distinct and thermally stable seven-transmembrane protein that functions as a light-driven proton (H+) pump with the chromophore retinal. To characterize its vectorial proton transport mechanism, mutational and theoretical investigations were performed for carboxylates in the transmembrane region of RxR and the sequential proton transport steps were revealed as follows: (i) a proton of the retinylidene Schiff base (Lys209) is transferred to the counterion Asp74 upon formation of the blue-shifted M-intermediate in collaboration with Asp205, and simultaneously, a respective proton is released from the proton releasing group (Glu187/Glu197) to the extracellular side, (ii) a proton of Asp85 is transferred to the Schiff base during M-decay, (iii) a proton is taken up from the intracellular side to Asp85 during decay of the red-shifted O-intermediate. This ion transport mechanism of RxR provides valuable information to understand other ion transporters since carboxylates are generally essential for their functions.No potential conflict of interest relevant to this article was reported.IOP PublishingActa Medica Okayama1755-130724032019Numerical study of air-entraining and submerged vortices in a pump sump032001ENShinichiroYanaseDepartment of Mechanical and Systems Engineering, Okayama UniversityRyoYamasakiTechnical Division, Tsurumi Manufacturing Co.ToshinoriKouchiDepartment of Mechanical and Systems Engineering, Okayama UniversityShunsukeHosodaDepartment of Mechanical and Systems Engineering, Okayama UniversityYasunoriNagataDepartment of Mechanical and Systems Engineering, Okayama UniversityHiguchiShunjiTechnical Division, Tsurumi Manufacturing Co.ToshihikoKawabeTechnical Division, Tsurumi Manufacturing Co.ToshihiroTakamiDepartment of Mechanical and Systems Engineering, Okayama University of ScienceNumerical detection of harmful vortices in pump sumps, such as an air-entraining vortex (AEV) and a submerged vortex (SMV), is crucially important to develop the drain pump machinery. We performed numerical simulations of the benchmark experiments of the pump sump conducted by Matsui et al. (2006 and 2016) using the OpenFOAM and compared the simulation results with the experimental data considering the effects of turbulence model, grid density and detection method of the vortices. We studied the threshold of the gas-liquid volume fraction of the VOF method and the second invariant of velocity gradient tensor to identify AEV and SMV. The methods proposed in the present paper were found to be very effective for the detection of the vortices, and the simulation results by RANS with the SST k-omega model successfully reproduced the experimental data. LES with the Smagorinsky model, however, was sensitive to the grid system and difficult to reproduce the experimental data even for the finest grid system having 3.7 million cells in the present study.No potential conflict of interest relevant to this article was reported.NatureActa Medica Okayama2045-23221012020Development of an experimental method of systematically estimating protein expression limits in HEK293 cells4798ENYoshihiroMoriGraduate School of Natural Science and Technology, Okayama UniversityYukiYoshidaSony Computer Science LaboratoriesAyanoSatohGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityHisaoMoriyaResearch Core for Interdisciplinary Sciences, Okayama UniversityProtein overexpression sometimes causes cellular defects, although the underlying mechanism is still unknown. A protein's expression limit, which triggers cellular defects, is a useful indication of the underlying mechanism. In this study, we developed an experimental method of estimating the expression limits of target proteins in the human embryonic kidney cell line HEK293 by measuring the proteins' expression levels in cells that survived after the high-copy introduction of plasmid DNA by which the proteins were expressed under a strong cytomegalovirus promoter. The expression limits of nonfluorescent target proteins were indirectly estimated by measuring the levels of green fluorescent protein (GFP) connected to the target proteins with the self-cleaving sequence P2A. The expression limit of a model GFP was similar to 5.0% of the total protein, and sustained GFP overexpression caused cell death. The expression limits of GFPs with mitochondria-targeting signals and endoplasmic reticulum localization signals were 1.6% and 0.38%, respectively. The expression limits of four proteins involved in vesicular trafficking were far lower compared to a red fluorescent protein. The protein expression limit estimation method developed will be valuable for defining toxic proteins and consequences of protein overexpression.No potential conflict of interest relevant to this article was reported.NatureActa Medica Okayama2045-23221012020Controlling Electronic States of Few-walled Carbon Nanotube Yarn via Joule-annealing and p-type Doping Towards Large Thermoelectric Power Factor7307ENMay Thu ZarMyintGraduate School of Natural Science and Technology, Okayama UniversityTakeshiNishikawaGraduate School of Natural Science and Technology, Okayama UniversityKazukiOmotoGraduate School of Natural Science and Technology, Okayama UniversityHirotakaInoueGraduate School of Natural Science and Technology, Okayama UniversityYoshifumiYamashitaGraduate School of Natural Science and Technology, Okayama UniversityAung Ko KoKyawDepartment of Electrical and Electronic Engineering, Southern University of Science and TechnologyYasuhikoHayashiGraduate School of Natural Science and Technology, Okayama UniversityFlexible, light-weight and robust thermoelectric (TE) materials have attracted much attention to convert waste heat from low-grade heat sources, such as human body, to electricity. Carbon nanotube (CNT) yarn is one of the potential TE materials owing to its narrow band-gap energy, high charge carrier mobility, and excellent mechanical property, which is conducive for flexible and wearable devices. Herein, we propose a way to improve the power factor of CNT yarns fabricated from few-walled carbon nanotubes (FWCNTs) by two-step method; Joule-annealing in the vacuum followed by doping with p-type dopants, 2,3,5,6-tetrafluo-7,7,8,8-tetracyanoquinodimethane (F4TCNQ). Numerical calculations and experimental results explain that Joule-annealing and doping modulate the electronic states (Fermi energy level) of FWCNTs, resulting in extremely large thermoelectric power factor of 2250 mu Wm(-1) K-2 at a measurement temperature of 423K. Joule-annealing removes amorphous carbon on the surface of the CNT yarn, which facilitates doping in the subsequent step, and leads to higher Seebeck coefficient due to the transformation from (semi) metallic to semiconductor behavior. Doping also significantly increases the electrical conductivity due to the effective charge transfers between CNT yarn and F4TCNQ upon the removal of amorphous carbon after Joule-annealing.No potential conflict of interest relevant to this article was reported.WileyActa Medica Okayama1356-95972512020Tree of motility : A proposed history of motility systems in the tree of life621ENMakotoMiyataDepartment of Biology, Graduate School of Science, Osaka City UniversityRobert C.RobinsonResearch Institute for Interdisciplinary Science, Okayama UniversityTaro Q. P.UyedaDepartment of Physics, Faculty of Science and Technology, Waseda UniversityYoshihiroFukumoriFaculty of Natural System, Institute of Science and Engineering, Kanazawa UniversityShun‐ichiFukushimaDepartment of Biological Sciences, Graduate School of Science and Engineering, Tokyo Metropolitan UniversityShinHarutaDepartment of Biological Sciences, Graduate School of Science and Engineering, Tokyo Metropolitan UniversityMichioHommaDivision of Biological Science, Graduate School of Science, Nagoya UniversityKazuoInabaShimoda Marine Research Center, University of TsukubaMasahiroItoGraduate School of Life Sciences, Toyo UniversityChikaraKaitoLaboratory of Microbiology, Graduate School of Pharmaceutical Sciences, The University of TokyoKentaroKatoLaboratory of Sustainable Animal Environment, Graduate School of Agricultural Science, Tohoku UniversityTsuyoshiKenriLaboratory of Mycoplasmas and Haemophilus, Department of Bacteriology II, National Institute of Infectious DiseasesYoshiakiKinositaDepartment of Physics, Oxford UniversitySeijiKojimaDivision of Biological Science, Graduate School of Science, Nagoya UniversityTohruMinaminoGraduate School of Frontier Biosciences, Osaka UniversityHiroyukiMoriInstitute for Frontier Life and Medical Sciences, Kyoto UniversityShuichiNakamuraDepartment of Applied Physics, Graduate School of Engineering, Tohoku UniversityDaisukeNakaneDepartment of Physics, Gakushuin UniversityKojiNakayamaDepartment of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki UniversityMasayoshiNishiyamaDepartment of Physics, Faculty of Science and Engineering, Kindai UniversitySatoshiShibataMolecular Cryo‐Electron Microscopy Unit, Okinawa Institute of Science and Technology Graduate UniversityKatsuyaShimabukuroDepartment of Chemical and Biological Engineering, National Institute of Technology, Ube CollegeMasatadaTamakoshiDepartment of Molecular Biology, Tokyo University of Pharmacy and Life SciencesAzumaTaokaFaculty of Natural System, Institute of Science and Engineering, Kanazawa UniversityYosukeTashiroDepartment of Engineering, Graduate School of Integrated Science and Technology, Shizuoka UniversityIsilTulumDepartment of Botany, Faculty of Science, Istanbul UniversityHirofumiWadaDepartment of Physics, Graduate School of Science and Engineering, Ritsumeikan UniversityKen‐ichiWakabayashiLaboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of TechnologyMotility often plays a decisive role in the survival of species. Five systems of motility have been studied in depth: those propelled by bacterial flagella, eukaryotic actin polymerization and the eukaryotic motor proteins myosin, kinesin and dynein. However, many organisms exhibit surprisingly diverse motilities, and advances in genomics, molecular biology and imaging have showed that those motilities have inherently independent mechanisms. This makes defining the breadth of motility nontrivial, because novel motilities may be driven by unknown mechanisms. Here, we classify the known motilities based on the unique classes of movement‐producing protein architectures. Based on this criterion, the current total of independent motility systems stands at 18 types. In this perspective, we discuss these modes of motility relative to the latest phylogenetic Tree of Life and propose a history of motility. During the ~4 billion years since the emergence of life, motility arose in Bacteria with flagella and pili, and in Archaea with archaella. Newer modes of motility became possible in Eukarya with changes to the cell envelope. Presence or absence of a peptidoglycan layer, the acquisition of robust membrane dynamics, the enlargement of cells and environmental opportunities likely provided the context for the (co)evolution of novel types of motility.No potential conflict of interest relevant to this article was reported.IOP PublishingActa Medica Okayama2515-7639232019Solid-state nuclear magnetic resonance study of setting mechanism of beta-tricalcium phosphate-inositol phosphate composite cementsENToshiisaKonishiGraduate School of Natural Science and Technology, Okayama UniversityKoheiYamashitaGraduate School of Natural Science and Technology, Okayama UniversityKoheiNagataOrganization for the Strategic Coordination of Research and Intellectual Property, Meiji UniversityPoon NianLimDepartment of Mechanical Engineering, National University of SingaporeEng SanThianDepartment of Mechanical Engineering, National University of SingaporeMamoruAizawaDepartment of Applied Chemistry, School of Science and Technology, Meiji UniversitySolid-state nuclear magnetic resonance (NMR) spectroscopy is a technique, which can be used to provide insight into the chemical structure of non-crystalline and crystalline materials. Hence, the present study aimed to elucidate the setting mechanism of CPC, which was fabricated using beta -tricalcium phosphate (beta -TCP)-inositol phosphate (IP6) composite powder using NMR In addition, the effect of IP6 on the local chemical structure of the beta -TCP-IP6 composite powder and its hardened cement would also be investigated. The H-1 -> P-31 heteronuclear correlation NMR spectrum revealed that an amorphous hydrated layer, along with small amount of hydroxyapatite (HA) was formed on the surface of beta -TCP during the ball-milling process. Results demonstrated that the IP6 in the hydrated layer on the surface of beta -TCP inhibited the formation of HA. Moreover, the setting reaction of the cement was mainly triggered by the dissolution of the amorphous hydrated layer on beta -TCP surface, and subsequent precipitation, followed by the inter-entanglement between the HA crystals on the beta -TCP.No potential conflict of interest relevant to this article was reported.Frontiers MediaActa Medica Okayama2296-634X82020In vitroNeo-Genesis of Tendon/Ligament-Like Tissue by Combination of Mohawk and a Three-Dimensional Cyclic Mechanical Stretch Culture System307ENKensukeKataokaDepartment of Systems BioMedicine, Tokyo Medical and Dental UniversityRyotaKurimotoDepartment of Systems BioMedicine, Tokyo Medical and Dental UniversityHirokiTsutsumiDepartment of Systems BioMedicine, Tokyo Medical and Dental UniversityTomokiChibaDepartment of Systems BioMedicine, Tokyo Medical and Dental UniversityTomomiKatoDepartment of Systems BioMedicine, Tokyo Medical and Dental UniversityKanaShishidoDepartment of Systems BioMedicine, Tokyo Medical and Dental UniversityMarikoKatoDepartment of Systems BioMedicine, Tokyo Medical and Dental UniversityYoshiakiItoDepartment of Systems BioMedicine, Tokyo Medical and Dental UniversityYuichiroChoAnatomy and Physiological Science, Tokyo Medical and Dental UniversityOsamuHoshiAnatomy and Physiological Science, Tokyo Medical and Dental UniversityAyakoMimataResearch Core, Tokyo Medical and Dental UniversityYurikoSakamakiResearch Core, Tokyo Medical and Dental UniversityRyoNakamichiDepartment of Systems BioMedicine, Tokyo Medical and Dental UniversityMartin K.LotzDepartment of Molecular Medicine, The Scripps Research InstituteKeijiNaruseGraduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityHiroshiAsaharaDepartment of Systems BioMedicine, Tokyo Medical and Dental UniversityTendons and ligaments are pivotal connective tissues that tightly connect muscle and bone. In this study, we developed a novel approach to generate tendon/ligament-like tissues with a hierarchical structure, by introducing the tendon/ligament-specific transcription factor Mohawk (MKX) into the mesenchymal stem cell (MSC) line C3H10T1/2 cells, and by applying an improved three-dimensional (3D) cyclic mechanical stretch culture system. In our developed protocol, a combination of stableMkxexpression and cyclic mechanical stretch synergistically affects the structural tendon/ligament-like tissue generation and tendon related gene expression. In a histological analysis of these tendon/ligament-like tissues, an organized extracellular matrix (ECM), containing collagen type III and elastin, was observed. Moreover, we confirmed thatMkxexpression and cyclic mechanical stretch, induced the alignment of structural collagen fibril bundles that were deposited in a fibripositor-like manner during the generation of our tendon/ligament-like tissues. Our findings provide new insights for the tendon/ligament biomaterial fields.No potential conflict of interest relevant to this article was reported.ElsevierActa Medica Okayama0921-50937912020The effect of precipitations (NbC and carbide) in Fe–C–Mn-xNb steels on hydrogen embrittlement characteristics139598ENMitsuhiroOkayasuGraduate School of Natural Science and Technology, Okayama UniversityMasayaSatoGraduate School of Natural Science and Technology, Okayama UniversityDaikiIshidaGraduate School of Natural Science and Technology, Okayama UniversityTakehideSenumaGraduate School of Natural Science and Technology, Okayama UniversityHydrogen embrittlement (HE) characteristics in Fe–C–Mn-xNb steels were examined via various analyses, including electron backscatter diffraction analysis, scanning transmission electron microscopy and three-dimensional atom-probe tomography. For the investigation, the steel samples were prepared with varying Nb contents and heat treatment processes. The material properties of steel samples that were subjected to: (i) water quenching and (ii) quenching and tempering at 170 °C for 20 min, were determined to be nearly similar, although different degrees of HE were detected. After the tempering process, ε-carbide precipitated clearly in the matrix, which could act as a trapping site for hydrogen atoms and lead to improved HE resistance. Moreover, with addition of Nb, niobium base precipitates (e.g., NbC) with a diameter of a few nanometers were obtained in the martensite matrix, which could also function as hydrogen trapping sites. There was slight improvement in the HE resistance with NbC. Hydrogen-assisted failure mechanisms under both static and cyclic loading were observed with intergranular brittle cracking for the water quenched sample, even though the brittle and ductile mix failure mode was detected for the sample after the quenching and tempering process.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2075-47011052020Influence of Continuous Casting Speeds on Cast Microstructure and Mechanical Properties of an ADC14 Alloy625ENYoon-SeokLeeGraduate School of Natural Science and Technology, Okayama UniversityYuyaMakinoGraduate School of Natural Science and Technology, Okayama UniversityJunNittaGraduate School of Natural Science and Technology, Okayama UniversityEunkyungLeeDepartment of Ocean Advanced Materials Convergence Engineering, Korea Maritime and Ocean UniversityTo improve the mechanical properties of the casting alloys, various attempts have been made to use alternative casting technologies. The Ohno continuous casting (OCC) process is a unidirectional solidification method, which leads to high-quality cast samples. In this study, the Al-Si-Cu-Mg alloy was cast at casting speeds of 1 mm/s, 2 mm/s, and 3 mm/s, by the OCC process. The aim of this study is to investigate the effects of the casting process parameters, such as casting speeds and cooling conditions, on the crystallization characteristics and mechanical properties of OCC-Al-Si-Cu-Mg alloy. Particularly, secondary dendrite arms spacing of alpha-Al dendrites in OCC samples significantly decreases with increasing casting speed. Moreover, the mean tensile strength of the samples, produced at the highest casting speed of 4.0 mm/s, is significantly higher than that for the samples produced at a casting speed of 1.0 mm/s. No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X7432020Stem Cell Therapy in Heart Disease: Limitations and Future Possibilities185190ENToshikazuSanoDepartment of Surgery, Division of Pediatric Cardiothoracic Surgery, University of California San FranciscoShutaIshigamiDepartment of Surgery, Division of Pediatric Cardiothoracic Surgery, University of California San FranciscoTatsuoItoDepartment of Hygiene, Kawasaki Medical UniversityShunjiSanoDepartment of Surgery, Division of Pediatric Cardiothoracic Surgery, University of California San FranciscoReview10.18926/AMO/59948Heart diseases are one of the major causes of morbidity and mortality worldwide. Despite major advances in drug and interventional therapies, surgical procedures, and organ transplantation, further research into new therapeutic options is still necessary. Stem cell therapy has emerged as one option for the treatment of a variety of heart diseases. Although a large number of clinical trials have shown stem cell therapy to be a promising therapeutic approach, the results obtained from these clinical studies are inconsistent, and stem cell-based improvements of heart performance and cardiac remodeling were found to be quite limited. Since the precise mechanisms underlying the therapeutic actions of stem cells are still under debate, researchers have developed a variety of strategies to improve and boost the potency of stem cells in repair. In this review, we summarize both the current therapeutic strategies using stem cells and future directions for enhancing stem cell potency.No potential conflict of interest relevant to this article was reported.ElsevierActa Medica Okayama0142-96122512020Heterotypic 3D pancreatic cancer model with tunable proportion of fibrotic elements120077ENHiroyoshi Y.TanakaGraduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama UniversityTsuyoshiKuriharaGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityTakuyaNakazawaGraduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama UniversityMichiyaMatsusakiDepartment of Applied Chemistry, Graduate School of Engineering, Osaka UniversityAtsushiMasamuneDivision of Gastroenterology, Graduate School of Medicine, Tohoku UniversityMitsunobu R.KanoGraduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama UniversityPancreatic ductal adenocarcinoma (PDAC) is an often lethal disease characterized by a dense, fibrotic stroma. However, the lack of relevant preclinical models that recapitulate the characteristic histopathology of human PDAC in vitro impedes the development of novel therapies. The amount of stromal elements differ largely within and between patients, but in vitro models of human PDAC often do not account for this heterogeneity. Indeed, analyses of human PDAC histopathology revealed that the proportion of stroma ranged from 40 to 80% across patients. We, therefore, generated a novel 3D model of human PDAC, consisting of co-cultured human PDAC tumor cells and fibroblasts/pancreatic stellate cells, in which the proportion of fibrotic elements can be tuned across the clinically observed range. Using this model, we analyzed the signaling pathways involved in the differentiation of myofibroblasts, a characteristic subpopulation of fibroblasts seen in PDAC. We show that both YAP and SMAD2/3 in fibroblasts are required for myofibroblastic differentiation and that both shared and distinct signaling pathways regulate the nuclear localization of these factors during this process. Our novel model will be useful in promoting the understanding of the complex mechanisms by which the fibrotic stroma develops and how it might be therapeutically targeted.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama1422-00672192020Induction of CEMIP in Chondrocytes by Inflammatory Cytokines: Underlying Mechanisms and Potential Involvement in Osteoarthritis3140ENTakashiOhtsukiDepartment of Medical Technology, Graduate School of Health Sciences, Okayama UniversityOmer F.HatipogluDepartment of Medical Technology, Graduate School of Health Sciences, Okayama UniversityKeiichiAsanoDepartment of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesJunkoInagakiDepartment of Cell Chemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesKeiichiroNishidaDepartment of Orthopaediac Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesSatoshiHirohataDepartment of Medical Technology, Graduate School of Health Sciences, Okayama UniversityIn patients with osteoarthritis (OA), there is a decrease in both the concentration and molecular size of hyaluronan (HA) in the synovial fluid and cartilage. Cell migration-inducing hyaluronidase 1 (CEMIP), also known as hyaluronan (HA)-binding protein involved in HA depolymerization (HYBID), was recently reported as an HA depolymerization-related molecule expressed in the cartilage of patients with OA. However, the underlying mechanism of CEMIP regulation is not well understood. We found that CEMIP expression was transiently increased by interleukine-1 beta (IL-1 beta) stimulation in chondrocytic cells. We also observed that ERK activation and NF-kappa B nuclear translocation were involved in the induction of CEMIP by IL-1 beta. In addition, both administration of HA and mechanical strain attenuated the CEMIP induction in IL-1 beta-stimulated chondrocytes. In conclusion, we clarified the regulatory mechanism of CEMIP in chondrocytes by inflammatory cytokines and suggested the potential involvement in osteoarthritis development.No potential conflict of interest relevant to this article was reported.ElsevierActa Medica Okayama092150937902020Microstructure-dependent hydrogen diffusion and trapping in high-tensile steel139418ENMitsuhiroOkayasuGraduate School of Natural Science and Technology, Okayama UniversityJunMotojimaGraduate School of Natural Science and Technology, Okayama UniversityIn this work, the hydrogen embrittlement (HE) characteristics of high-tensile steel sheets with different microstructural characteristics were investigated. The sheets were fabricated via cold rolling (CR), water quenching (WQ), baking hardening (BH), and low-temperature annealing (LT), and their HE characteristics were clarified by examining the relationships between the microstructural characteristics and the severity of HE. Severe HE occurred in the WQ sample with hydrogen trapping at the boundaries of the retained austenite phases, resulting in intergranular and cleavage-like brittle failure. A reduction in HE was realized after the BH and LT processes. In these cases, hydrogen trapping was divided between the ε-carbide in the lattice spacings and at the boundaries of retained austenite, resulting in a mixed ductile/brittle failure mode. The extent of HE in the CR sample was similar to those in the BH and LT samples. However, the trapping sites were different; hydrogen trapping in the CR sample occurred in the slip band and around dislocations, resulting in delamination-like brittle failure on the slip planes. The extent of HE was also affected by the strain rate. More severe HE occurred in both the WQ and BH samples loaded slowly at 0.01 mm min−1 compared to the samples loaded 1.0 mm min−1 (i.e., intergranular failure). In this case, HE was affected by the large amount of hydrogen atoms trapped at the boundaries of the retained austenite phases. The hydrogen atoms in the lattice structure and ε-carbide migrated to the boundaries via dislocation movement. The extent of deterioration in tensile strength was two times higher in the samples loaded at the higher speed of 1.0 mm min−1 compared to those loaded at 0.01 mm min−1. Finally, the hydrogen trapping and failure mechanisms on the nano and atomic scales were discussed based on the results of the microstructural analyses.No potential conflict of interest relevant to this article was reported.American Association for the Advancement of ScienceActa Medica Okayama2375-2548552019Layer-specific activation of sensory input and predictive feedback in the human primary somatosensory cortexeaav9053ENYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems,Okayama UniversityLaurentiusHuberSection on Functional Imaging Methods, National Institute of Mental HealthJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems,Okayama UniversityDavid C.JangrawSection on Functional Imaging Methods, National Institute of Mental HealthDaniel A.HandwerkerSection on Functional Imaging Methods, National Institute of Mental HealthPeter J.MolfeseSection on Functional Imaging Methods, National Institute of Mental HealthGangChenScientific and Statistical Computing Core, National Institute of Mental HealthYoshimichiEjimaGraduate School of Interdisciplinary Science and Engineering in Health Systems,Okayama UniversityJinglongWuGraduate School of Interdisciplinary Science and Engineering in Health Systems,Okayama UniversityPeter A.BandettiniSection on Functional Imaging Methods, National Institute of Mental HealthWhen humans perceive a sensation, their brains integrate inputs from sensory receptors and process them based on their expectations. The mechanisms of this predictive coding in the human somatosensory system are not fully understood. We fill a basic gap in our understanding of the predictive processing of somatosensation by examining the layer-specific activity in sensory input and predictive feedback in the human primary somatosensory cortex (S1). We acquired submillimeter functional magnetic resonance imaging data at 7T (n = 10) during a task of perceived, predictable, and unpredictable touching sequences. We demonstrate that the sensory input from thalamic projects preferentially activates the middle layer, while the superficial and deep layers in S1 are more engaged for cortico-cortical predictive feedback input. These findings are pivotal to understanding the mechanisms of tactile prediction processing in the human somatosensory cortex.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama1422-006720232019Multipotent Neurotrophic Effects of Hepatocyte Growth Factor in Spinal Cord Injury6078ENKentaroYamaneDepartment of Intelligent Orthopaedic System Development, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesHaruoMisawaDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesTomoyukiTakigawaDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesYoshihiroItoNano Medical Engineering Laboratory, RIKENToshifumiOzakiDepartment of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesAkihiroMatsukawaDepartment of Pathology and Experimental Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesSpinal cord injury (SCI) results in neural tissue loss and so far untreatable functional impairment. In addition, at the initial injury site, inflammation induces secondary damage, and glial scar formation occurs to limit inflammation-mediated tissue damage. Consequently, it obstructs neural regeneration. Many studies have been conducted in the field of SCI; however, no satisfactory treatment has been established to date. Hepatocyte growth factor (HGF) is one of the neurotrophic growth factors and has been listed as a candidate medicine for SCI treatment. The highlighted effects of HGF on neural regeneration are associated with its anti-inflammatory and anti-fibrotic activities. Moreover, HGF exerts positive effects on transplanted stem cell differentiation into neurons. This paper reviews the mechanisms underlying the therapeutic effects of HGF in SCI recovery, and introduces recent advances in the clinical applications of HGF therapy.No potential conflict of interest relevant to this article was reported.岡山大学経済学会Acta Medica Okayama2433-4146512-32020現代ポーランドの国家発展戦略と経済成長の原動力1537ENMasahiroTaguchiGraduate School of Humanities and Social Sciences, Okayama UniversityTakuOkazaki10.18926/OER/58070 In this paper, authors analyze the changes in the national development strategies of the Polish government since the First World War, the state investment that became the driving force of economic development, the trends and positions of foreign capital, and the changes in the economic environment surrounding the Polish economy. In the Second Republic, economic liberalism was a widely supported philosophy in the business world and academic society. However, in order to support very weak economic fundamentals, the government seized the key industry and tried to rebuild the economy. Although foreign capital played a very important role in economic development, Polish people’s distrust in foreign capital was strong. After the Great Depression, the Central Industrial District（ CUP） was built under the leadership of the government. However, with the outbreak of World War II, the formation of a strong core industrial base was suspended.<br/>
After the Second World War, the government initially aimed to build a Peoples Democracy system based on pluralism. However, when the Cold War sharpened, rapid industrialization and collectivization of agriculture were forced. The Stalinist economic development strategy failed in a few years. Nevertheless, from the end of the 1950s, mining development and industrialization based on the mechanical and chemical industries were carried out again. This industrialization of capital goods sector-oriented production has distorted the people’s consumer life. However, in the long run, it cannot be denied that the industrialization of that time became the basis for the formation of the wide promising fields of the Polish industry. Since 1970, an open economic strategy has been adopted. Modernization was attempted by introducing licenses from the west. However, new investments did not lead to expansion of export, and cumulative debt increased. During the economic crisis, the“ Solidarity” movement quickly grew into a national movement, but this did not lead to a fundamental economic system change. Economic reform was also attempted in the 1980s. However, the socialist economic system was unable to adapt to the new global economic system driven by innovation. The inflexible system lost its growth potential.<br/>
After the collapse of socialist system in 1989, radical liberalization policies drastically improved economic imbalances, and the economic policy enabled high growth. During the transition period, foreign capital greatly contributed to growth. The automobile industry is a good example. This industry is associated with wide parts production. Many domestic intermediate goods manufacturers increased their orders, and their technical capabilities were rapidly improved through the guidance of foreign capital. In addition, export has improved significantly due to the expansion of production by foreign-affiliated companies. In contrast to the Second Republic, foreign capital played a major role in nurturing domestic industries. By the end of the 1990s, the Russian economy had had no effect on the Polish economy. At the transition period, the Polish industry shifted rapidly to the EU. At the same time, since the manufacturing field was the foundation of Polish growth, the impact of the 2007 global financial crisis wasn’t serious. Not only that, Poland maintained positive growth in 2008 as most countries in Europe fell into negative Currently, low-wage, low-value-added production based on FDI inflows and abundant labor force is the driving force for growth. In the medium and long term, the Polish economy cannot grow if it stays in the current subcontract production status of industrialized countries. The key to Poland’s escape from the “middle-income trap” is how to develop“ new Polish companies” that produce high-value-added products and services under global competition.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2075-4701972019Effect of Lubrication and Forging Load on Surface Roughness, Residual Stress, and Deformation of Cold Forging Tools783ENNuwanKarunathilakaGraduate School of Natural Science and Technology, Okayama UniversityNaoyaTadaGraduate School of Natural Science and Technology, Okayama UniversityTakeshiUemoriGraduate School of Natural Science and Technology, Okayama UniversityRyotaHanamitsuGraduate School of Natural Science and Technology, Okayama UniversityMasahiroFujiiGraduate School of Natural Science and Technology, Okayama UniversityYuyaOmiyaGraduate School of Natural Science and Technology, Okayama UniversityMasahiroKawanoZeno Tech Co., LtdCold forging is a metal forming that which uses localized compressive force at room temperature. During the cold forging process, the tool is subjected to extremely high loads and abrasive wear. Lubrication plays an important role in cold forging to improve product quality and tool life by preventing direct metallic contact. Surface roughness and residual stress also greatly affects the service life of a tool. In this study, variations in surface roughness, residual stress, and specimen deformation with the number of cold forging cycles were investigated under different forging conditions. Specimens that were made of heat-treated SKH51 (59-61 HRC), a high-speed tool steel with a polished working surface, were used. The specimens were subjected to an upsetting process. Compressive residual stress, surface roughness, and specimen deformation showed a positive relationship with the number of forging cycles up to a certain limit and became almost constant in most of the forging conditions. A larger change in residual stress and surface roughness was observed at the center of the specimens in all the forging conditions. The effect of the magnitude of the forging load on the above discussed parameters is large when compared to the effect of the lubrication conditions.No potential conflict of interest relevant to this article was reported.Spandidos PublicationsActa Medica Okayama1792-10741832019Cancer stem cell induction from mouse embryonic stem cells27562762ENAkimasaSenoLaboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityChikaeMurakamiDepartment of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama UniversityBishoyEl‑AaragLaboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYoshiakiIwasakiHealth Service Center, Okayama UniversityToshiakiOharaDepartment of Pathology and Experimental MedicineOkayama University Graduate School of Medicine, Dentistry, and Pharmaceutical SciencesMasaharuSenoLaboratory of Nano-Biotechnology, Okayama University Graduate School of Interdisciplinary Science and Engineering in Health Systems Although cancers are often removed by surgery and treated by chemotherapy and/or radiation therapies, they often reoccur following treatment due to the presence of resistant residual cells such as cancer stem cells (CSCs). CSCs are characterized by their self-renewal, pluripotency, and tumorigenicity properties, and are promising therapeutic targets for the complete therapy of cancers; however, the number of CSCs in cancer tissue is typically too small to investigate fully. We have previously reported that CSCs could be established from induced pluripotent stem cells (iPSCs) using a conditioned medium during cancer cell culture. In the present study, mouse embryonic stem cells (mESCs) were observed to be converted to CSCs (mES-CSCs). This demonstrated that CSC induction does not exclusively occur following gene editing in somatic cells, and that conditioned medium from cancer cells may contain factors that can induce CSCs. Therefore, not only iPSCs but also mESCs, were demonstrated to be able to produce CSCs as one of the potentials of pluripotency of stem cells, suggesting that the conversion to CSCs is not specific to iPSCs. The resultant mES-CSCs would be also useful to generate tissue specific cancers and these naturally occurring cancers can contribute to drug screenings, but also undergo further investigation in order to reveal cancer mechanisms.No potential conflict of interest relevant to this article was reported.ElsevierActa Medica Okayama209044792019CO2 concentration measurements inside expansion-compression engine under high EGR conditions using an infrared absorption methodENFatma B.M.AhmedDepartment of Physics, Faculty of Science, Aswan UniversityMohamed F.C.EsmailDepartment Mechanical Power Engineering, Faculty of Energy Engineering, Aswan UniversityNobuyukiKawaharaDepartment of Mechanical Engineering, Okayama UniversityEijiTomitaDepartment of Mechanical Engineering, Okayama UniversityThe purpose of this study is to measure the high concentrations of CO2 near a spark plug inside an internal combustion engine, and an infrared absorption method is used for the measurement. The spark plug sensor was adapted to a compression-expansion machine, and the CO2 concentration near the spark plug was measured by adding a gas mixture, including CO2 to imitate EGR. Next, the EGR ratio was changed from 10 to 40%, and the CO2 concentration was measured. The effect of the CO2 on the flame propagation was investigated by visualizing the bottom view of the compression-expansion machine. The measurements of CO2 mass concentration are in agreement with those predicted by direct-absorption spectroscopy fundamental theory from the crank angle −60 to −15 deg ATDC. The error was less than 20%, and under the conditions with an EGR ratio of 20–40%.No potential conflict of interest relevant to this article was reported.Nature Publishing GroupActa Medica Okayama2045-232292019Yeast screening system reveals the inhibitory mechanism of cancer cell proliferation by benzyl isothiocyanate through down-regulation of Mis128866ENNaomiAbe-KanohGraduate School of Environmental and Life Science, Okayama UniversityNarumiKunisueGraduate School of Environmental and Life Science, Okayama UniversityTakumiMyojinGraduate School of Environmental and Life Science, Okayama UniversityAyakoChinoResearch Core for Interdisciplinary Sciences, Okayama UniversityShintaroMunemasaGraduate School of Environmental and Life Science, Okayama UniversityYoshiyukiMurataGraduate School of Environmental and Life Science, Okayama UniversityAyanoSatoh Graduate School of Natural Science and Technology, Okayama UniversityHisaoMoriyaResearch Core for Interdisciplinary Sciences, Okayama UniversityYoshimasaNakamuraGraduate School of Environmental and Life Science, Okayama University, OkayamaBenzyl isothiocyanate (BITC) is a naturally-occurring isothiocyanate derived from cruciferous vegetables. BITC has been reported to inhibit the proliferation of various cancer cells, which is believed to be important for the inhibition of tumorigenesis. However, the detailed mechanisms of action remain unclear. In this study, we employed a budding yeast Saccharomyces cerevisiae as a model organism for screening. Twelve genes including MTW1 were identified as the overexpression suppressors for the antiproliferative effect of BITC using the genome-wide multi-copy plasmid collection for S. cerevisiae. Overexpression of the kinetochore protein Mtw1 counteracts the antiproliferative effect of BITC in yeast. The inhibitory effect of BITC on the proliferation of human colon cancer HCT-116 cells was consistently suppressed by the overexpression of Mis12, a human orthologue of Mtw1, and enhanced by the knockdown of Mis12. We also found that BITC increased the phosphorylated and ubiquitinated Mis12 level with consequent reduction of Mis12, suggesting that BITC degrades Mis12 through an ubiquitin-proteasome system. Furthermore, cell cycle analysis showed that the change in the Mis12 level affected the cell cycle distribution and the sensitivity to the BITC-induced apoptosis. These results provide evidence that BITC suppresses cell proliferation through the post-transcriptional regulation of the kinetochore protein Mis12.No potential conflict of interest relevant to this article was reported.WileyActa Medica Okayama1549-329610752019Biomimetic mineralization using matrix vesicle nanofragments10211030ENYosukeKunitomiDepartment of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesEmilio SatoshiHaraDepartment of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesMasahiroOkadaDepartment of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesNoriyukiNagaokaAdvanced Research Center for Oral and Craniofacial Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesTakuoKubokiDepartment of Oral Rehabilitation and Regenerative Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesTakayoshiNakanoDivision of Materials and Manufacturing Science, Graduate School of Engineering, Osaka UniversityHiroshiKamiokaDepartment of Orthodontics, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesTakuyaMatsumotoDepartment of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences In vitro synthesis of bone tissue has been paid attention in recent years; however, current methods to fabricate bone tissue are still ineffective due to some remaining gaps in the understanding of real in vivo bone formation process, and application of the knowledge in bone synthesis. Therefore, the objectives of this study were first, to perform a systematic and ultrastructural investigation of the initial mineral formation during intramembranous ossification of mouse calvaria from a material scientists' viewpoint, and to develop novel mineralization methods based on the in vivo findings. First, the very initial mineral deposition was found to occur at embryonic day E14.0 in mouse calvaria. Analysis of the initial bone formation process showed that it involved the following distinct steps: collagen secretion, matrix vesicle (MV) release, MV mineralization, MV rupture, and collagen fiber mineralization. Next, we performed in vitro mineralization experiments using MVs and hydrogel scaffolds. Intact MVs embedded in collagen gel did not mineralize, whereas, interestingly, MV nanofragments obtained by ultrasonication could promote rapid mineralization. These results indicate that mechanically ruptured MV membrane can be a promising material for in vitro bone tissue synthesis. No potential conflict of interest relevant to this article was reported.