MDPI AG Acta Medica Okayama 2075-1729 16 10 2026 Purification, Structural Characterization, and Genomic Insights of an Anti-MRSA Peptide from Mangrove-Derived Brevibacillus sp. A34 1697 EN Thanyamai Thongin School of Pharmacy, Walailak University Namfa Sermkaew School of Pharmacy, Walailak University Apichart Atipairin School of Pharmacy, Walailak University Sucheewin Krobthong Center of Excellence in Natural Products Chemistry (CENP), Department of Chemistry, Faculty of Science, Chulalongkorn University Chanat Aonbangkhen Center of Excellence in Natural Products Chemistry (CENP), Department of Chemistry, Faculty of Science, Chulalongkorn University Jumpei Uchiyama Department of Infectious Diseases, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama 700-8558, Japan Nuttapon Songnaka School of Pharmacy, Walailak University The widespread prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in community and healthcare settings has driven the urgent search for novel antibacterial agents. Mangrove sediments are an underexplored source of antimicrobial-producing bacteria. This study characterized an antimicrobial fraction and the genome of the mangrove-derived isolate Brevibacillus sp. A34. The active fraction was purified via ammonium sulfate precipitation, cation-exchange chromatography, and reversed-phase chromatography. De novo MS/MS analysis assigned the octapeptide LLLLLLAH (905.19 Da), designated as A34 AMP, which was further confirmed by chemical synthesis. This active peptide inhibited all four tested S. aureus strains, including three MRSA strains, with a minimum inhibitory concentration (MIC) of 62 µg/mL. At 2× and 4× MIC, A34 AMP exhibited a concentration-dependent bactericidal effect within 20 h. Increased SYTOX Green uptake and morphological alterations supported a membrane permeabilization mechanism, and antimicrobial activity was retained following thermal, pH, protease, and surfactant treatments. Genome mining identified 23 putative biosynthetic gene clusters, including an 11-module nonribosomal peptide synthetase (NRPS) cluster linked to A34 AMP through three-dimensional adenylation-domain modeling. Collectively, these findings highlight A34 AMP from Brevibacillus sp. A34 as a promising bioactive anti-staphylococcal peptide scaffold. No potential conflict of interest relevant to this article was reported.

IOP Publishing Acta Medica Okayama 0021-4922 65 7 2026 Study of preload mechanism for small piezoelectric transducers with hollow structure for cryogenic environments 07SP13 EN Souta Mimura Graduate School of Environment, Life, Natural Science and Technology, Okayama University Takefumi Kanda Graduate School of Environment, Life, Natural Science and Technology, Okayama University Daisuke Yamaguchi Graduate School of Environment, Life, Natural Science and Technology, Okayama University Kazuki Kubo Graduate School of Environment, Life, Natural Science and Technology, Okayama University Shuichi Wakimoto Graduate School of Environment, Life, Natural Science and Technology, Okayama University In various industrial fields, cryogenic fluids such as liquid hydrogen and liquid nitrogen are increasingly used as fuels and refrigerants. To control the flow rate of those fluids, valves that can be operated in cryogenic environments are needed. In general, the miniaturization of the valve can be achieved by using a piezoelectric ceramic as an actuator to drive the mechanism. Additionally, the properties degradation can be suppressed by applying a preload to the piezoelectric ceramic. To miniaturize the piezoelectric actuator applying preload at low temperature conditions, we use differences in thermal expansion coefficients to apply preload to the piezoelectric ceramics. In this study, we have designed and fabricated a small piezoelectric transducer with a hollow structure for cryogenic environments by using this proposed structure. To evaluate the fabricated transducer, we have measured vibration velocity and estimated the acceleration in cryogenic environments. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0289-0771 2026 Temporally structured plasticity in death-feigning behavior in response to nutritional conditions in Tribolium castaneum EN Kohjiro Shibuya Faculty of Environmental, Life, Natural Science and Technology, Okayama University Kentarou Matsumura Department of General Systems Studies, Graduate School of Arts and Sciences, The University of Tokyo Takahisa Miyatake Faculty of Environmental, Life, Natural Science and Technology, Okayama University Investment in antipredator behavior and foraging both directly influence fitness, yet these investments are often subject to trade-offs. In income-breeding species, individuals may initially prioritize foraging after adult emergence and subsequently increase investment in antipredator behavior as their nutritional condition improves. In this study, we investigated temporal changes in death-feigning behavior, an antipredator response, in the red flour beetle Tribolium castaneum from immediately after adult emergence. Both fed and starved individuals exhibited an increase in death-feigning duration with time after emergence. However, in starved individuals, this trend reversed after approximately 15 days, with a marked decline in duration. These results suggest that the increase in investment in death-feigning behavior early in adulthood is relatively inflexible, whereas behavioral responses become highly plastic in response to environmental conditions around day 15. Furthermore, individuals that were fed until day 18 before starvation showed a less pronounced behavioral change than those subjected to starvation from the beginning of the experimental period, suggesting that the timing of environmental exposure may influence subsequent behavioral responses. Together, these findings suggest that behavioral plasticity is not constant over time but is instead structured across developmental stages. We propose a novel conceptual framework, termed temporally structured plasticity (TSP), to describe this pattern. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2045-2322 16 1 2026 Cinnamyl alcohol dehydrogenase (CAD) underlies the orange lemma trait and lignin reduction in barley 30805 EN Kazuhiro Sato Institute of Plant Science and Resources, Okayama University Maho Morita Institute of Plant Science and Resources, Okayama University Nami Yamaji Institute of Plant Science and Resources, Okayama University Rinka Kako Graduate School of Agricultural Science, Setsunan University Tomokazu Ushijima Graduate School of Agricultural Science, Setsunan University Hiroshi Hisano Institute of Plant Science and Resources, Okayama University Barley (Hordeum vulgare L.) is one of the world’s major cereal crops and is widely used for feed, brewing, and food. Reducing lignin content in barley grain and straw is beneficial for improving forage digestibility and enhancing the efficiency of bioethanol production. The orange lemma mutation—characterized by orange pigmentation of husks and nodes—has long been associated with altered lignin metabolism; however, its genetic basis has remained unclear. We show that Cinnamyl Alcohol Dehydrogenase (CAD) is the causal gene underlying the orange lemma phenotype in barley. Genetic mapping using a ‘Haruna Nijo’ × ‘L053’ F₂ population and the Barley 50 K SNP array defined a candidate region on chromosome 6H containing the CAD gene. Sequence analysis revealed that all orange lemma mutants, including both naturally occurring and EMS-induced lines, carried nucleotide changes in the CAD gene, resulting in amino acid substitutions or premature stop codons. Furthermore, CRISPR/Cas9-mediated knockout of CAD in the cultivar ‘Golden Promise’ reproduced the orange lemma phenotype, providing functional validation. The knockout plants also showed significantly lower lignin content than wild-type plants. These findings resolve a long-standing question regarding the genetic basis of the orange lemma trait and demonstrate that disruption of CAD alters lignin accumulation in barley. This work provides a valuable genetic resource for breeding barley cultivars with improved biomass utilization for feed and bioenergy applications. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0289-0771 2026 Experimental evolution of female mating responses to infertile males in Tribolium castaneum EN Yui Fujii Faculty of Environmental, Natural Science and Technology, Okayama University Yui Asano Faculty of Environmental, Natural Science and Technology, Okayama University Kenta Kori Faculty of Environmental, Natural Science and Technology, Okayama University Kentarou Matsumura Graduate School of Arts and Sciences, The University of Tokyo Yukio Yasui Faculty of Agriculture, Kagawa University Chihiro Himuro Okinawa Prefectural Plant Protection Center Yutaka Nakamoto Okinawa Prefectural Plant Protection Center Yoshitaka Sokei Okinawa Prefectural Plant Protection Center Takahisa Miyatake Faculty of Environmental, Natural Science and Technology, Okayama University In many animal populations, infertile males—those unable to reproduce—are commonly present. If females mate exclusively with such males, they fail to produce offspring. How, then, do females deal with this situation? Distinguishing infertile from fertile males both before and after copulation is difficult for females. Here, we tested the hypothesis of bet-hedging polyandry, in which females mitigate the risk of reproductive failure by mating with multiple males, using experimental evolution in the red flour beetle (Tribolium castaneum). Females were cohabited with males artificially sterilized by sublethal radiation and with untreated males at a 1:1 ratio (sterile:untreated). After more than 15 generations, females from the treatment strains did not avoid mating with infertile males, leading to reduced reproductive success. However, compared with the control strains, females from the treated strains tended to mate with a greater number of males. The results raise the possibility that increased polyandry (mating with multiple males) may evolve rather than relying on pre- or post-copulatory discrimination to mitigate the risk posed by infertile males. Bet-hedging is a strategy that spreads or minimizes risk under uncertainty, and these results are consistent with the hypothesis that polyandry can function as a bet-hedging strategy against uncertain male fertility. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0340-5443 80 11 2026 No evidence for differential allocation or sex ratio adjustment in response to male attractiveness in the broad-horned flour beetle 132 EN Kensuke Okada Faculty of Environmental, Life, Natural Science and Technology, Okayama University Katsuya Kiyose Seibukasei Co., Ltd Masako Katsuki Graduate School of Bioagricultural Sciences, Nagoya University Sexual selection theory predicts that females can enhance the benefits of mate choice by increasing reproductive investment (differential allocation) or by biasing offspring sex ratios toward sons (sex ratio adjustment) when mating with attractive males. Clear empirical support for these hypotheses has been documented in many vertebrate taxa, whereas relatively few studies have tested them in invertebrates. Here, we investigated whether females adjust reproductive investment and offspring sex ratio in response to male attractiveness in the beetle Gnatocerus cornutus. We assessed male attractiveness using copulation latency and examined its associations with female lifetime reproductive success, egg size, and offspring sex ratio under single-mating conditions. Our results, however, provide no support for either the differential allocation or sex ratio adjustment hypotheses: females did not alter reproductive investment or offspring sex ratio according to mate quality. In this species, male sexual phenotypes are strongly influenced by environmental conditions. Such phenotype–genotype mismatches may reduce the reliability of male traits as indicators of genetic quality and increase the likelihood of assessment errors by females. This may explain the absence of maternal allocation in relation to mate attractiveness in G. cornutus. Instead, previous work on this beetle indicates that females can secure genetic benefits by remating with more attractive males and biasing fertilization toward their sperm. Our findings therefore suggest that postcopulatory mechanisms, rather than differential maternal allocation, provide a more effective route for females to secure the benefits of mate choice in G. cornutus. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0308-8146 526 2026 Flavor encapsulation capacities of amphiphilic polyvinylpyrrolidone as a carrier for amorphous solid dispersions 150819 EN Haruna Sato Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nao Honda Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takato Hasegawa Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Chika Araga Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hiroyuki Imanaka Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Naoyuki Ishida Department of Chemical Engineering and Material Sciences, Faculty of Science and Engineering, Doshisha University Koreyoshi Imamura Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University This study investigates the characteristics of amorphous solid dispersions (ASDs) formed using an amphiphilic carrier polymer, focusing on the effects of source solution conditions on flavor retention. Cinnamaldehyde and polyvinylpyrrolidone (PVP) were dissolved as flavor and carrier components in methanol or ethanol under different conditions and subsequently spray-dried into fine powders. The amount of cinnamaldehyde retained in the spray-dried ASDs was quantified to assess the impact of solution conditions. The results indicate that cinnamaldehyde molecules were physically entrapped within the entangled PVP chains during the spray-drying process. The flavor encapsulation capacity of PVP reached a maximum of approximately 4 mmol/g-PVP under specific conditions. This maximum capacity implies that each cinnamaldehyde molecule is associated with approximately two PVP monomer units, which is higher than those reported for selected cyclodextrin-based systems in comparable contexts of cinnamaldehyde encapsulation. Additionally, the dissipation of cinnamaldehyde from the ASD samples during storage under vacuum was examined. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 1718-7729 33 6 2026 Limited Immune-Mediated Efficacy of Anti-PD-L1/VEGF in EGFR-TKI-Naïve Egfr-Mutant Lung Cancer with Non-Inflamed Tumor Microenvironment 315 EN Atsuko Hirabae Department of Hematology, Oncology and Respiratory Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tadahiro Kuribayashi Department of Hematology, Oncology and Respiratory Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shuta Tomida Center for Comprehensive Genomic Medicine, Okayama University Hospital Sachi Okawa Department of Hematology, Oncology and Respiratory Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takamasa Nakasuka Department of Hematology, Oncology and Respiratory Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kazuya Nishii Department of Hematology, Oncology and Respiratory Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Jun Nishimura Department of Hematology, Oncology and Respiratory Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Go Makimoto Department of Respiratory Medicine, Okayama University Hospital Kiichiro Ninomiya Center for Comprehensive Genomic Medicine, Okayama University Hospital Hisao Higo Department of Hematology, Oncology and Respiratory Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kammei Rai Center for Innovative Clinical Medicine, Okayama University Hospital Eiki Ichihara Center for Clinical Oncology, Okayama University Hospital Katsuyuki Hotta Center for Innovative Clinical Medicine, Okayama University Hospital Masamichi Sugimoto Product Research Department, Kamakura Research Laboratories, Chugai Pharmaceutical Co., Ltd. Yosuke Togashi Department of Respiratory Medicine, Okayama University Hospital Yoshinobu Maeda Department of Hematology, Oncology and Respiratory Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Katsuyuki Kiura Department of Respiratory Medicine, Okayama University Hospital Kadoaki Ohashi Department of Respiratory Medicine, Okayama University Hospital Immune checkpoint inhibitors (ICIs) show limited efficacy in epidermal growth factor receptor (EGFR)-mutant lung adenocarcinoma due to its non-inflamed tumor microenvironment (TME). While quadruple therapy combining chemotherapy, anti-programmed death-ligand 1 (PD-L1), and anti-vascular endothelial growth factor (VEGF) antibodies has shown inconsistent results in EGFR-tyrosine kinase inhibitor (TKI)-pretreated patients, whether anti-VEGF therapy can modulate the intrinsic non-inflamed TME remains unknown. We employed an EGFR-TKI-naïve syngeneic Egfr-mutant mouse model and evaluated effects of anti-VEGF, anti-PD-L1, carboplatin, and paclitaxel as monotherapies and combinations, with TME analysis via immunohistochemistry (IHC), flow cytometry, and RNA sequencing. Anti-PD-L1 showed no antitumor effect, and adding anti-VEGF failed to convert the TME to an inflamed status. Although paclitaxel—but not carboplatin—combined with low-dose anti-VEGF inhibited tumor growth, adding anti-PD-L1 provided no benefit, indicating the anti-VEGF-A antibody evaluated here has a limited role in sensitizing tumors to anti-PD-L1 regardless of chemotherapy. CD8+ T-cell depletion did not attenuate the effect of paclitaxel plus low-dose anti-VEGF, and IHC and RNA sequencing revealed increased natural killer cell infiltration, suggesting a CD8+ T-cell-independent, innate immune mechanism. These findings provide preclinical evidence that the evaluated anti-VEGF has limited immunomodulatory activity in EGFR-TKI-naïve Egfr-mutant tumors with a non-inflamed TME, and suggest immunotherapeutic strategies beyond CD8+ T-cell-mediated immunity warrant investigation. No potential conflict of interest relevant to this article was reported.

Oxford University Press (OUP) Acta Medica Okayama 0366-7022 55 9 2026 Size-dependent reflection behavior of graphene oxide-based photonic crystals upag176 EN Daisuke Ogawa Department of Chemistry and Materials, Faculty of Textile Science and Technology, Shinshu University Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Koki Sano Department of Chemistry and Materials, Faculty of Textile Science and Technology, Shinshu University Graphene oxide (GO) nanosheets can spontaneously self-assemble into photonic crystals in water, exhibiting structural colors based on Bragg reflection. In this study, we systematically investigated the effect of GO lateral size on the reflection behavior of GO-based photonic crystals. Reflection spectroscopy revealed that both the reflection peak intensity and its time-dependent evolution strongly depended on the GO lateral size, suggesting the existence of an optimal size range for maximizing their reflection intensity. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0931-2250 212 6 2026 Validation and Fine Mapping of Quantitative Trait Loci Associated With Salinity Tolerance at Reproductive Stage on Chromosome 6 in the Rice Variety Nona Bokra e70252 EN M M Emam Ahmed Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Koki Maeoka Graduate School of Environment and Life Science, Okayama University Yuki Sakata School of Agriculture, Okayama University Asami Tomita Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yoshihiko Hirai Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Soil salinity is a major abiotic stress affecting rice production globally. Previously, one promising salinity-tolerant line (SL535) was identified through screening of Nona Bokra-CSSLs with a Koshihikari background. In 2016, 102 F2 individuals derived from SL535/Koshihikari were evaluated under long-term salt stress, with salt treatment imposed from the active tillering stage to maturity to investigate salt tolerance at the reproductive stage. Three QTLs for plant dry weight, panicle number, and panicle weight were detected on chromosome 6. This genomic region was further validated in 2019 and 2020 for plant dry weight, tiller number, and Na+ and Cl− contents using homozygous lines with or without the Nona Bokra allele in a Koshihikari background. As expected, significantly higher tiller number and lower Na+ and Cl− contents were maintained in plants carrying the Nona Bokra allele (NIL) at the full-heading stage. In 2023, seven newly developed NILs were evaluated for agronomic traits under control and salt stress conditions. Based on their performance, the QTL for plant dry weight, qPDW6.1, was narrowed down to a 390 kb region ranging from 4.78 to 5.17 Mb on chromosome 6. Within this region, several stress-related candidate genes were predicted based on annotation information and variant effect prediction analysis. Among them, two genes, Os06g0196700 (Auxin response factor 1) and Os06g0199100 (P-type pentatricopeptide repeat protein), were considered the most likely candidate genes associated with salt tolerance. These findings provide a foundation for future gene cloning and functional validation studies, which may help elucidate the genetic and molecular mechanisms underlying salt tolerance at the reproductive stage. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 1422-0067 27 19 2026 Impaired Myostatin Function Alters Body Composition Without Detectable Attenuation of Imiquimod-Induced Psoriasiform Dermatitis 8518 EN Yoshihiro Matsuda Department of Dermatology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shin Morizane Department of Dermatology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuma Sakamoto Department of Immunology and Molecular Genetics, Kawasaki Medical School Nobuyasu Baba Department of Immunology and Molecular Genetics, Kawasaki Medical School Masanori Iseki Department of Immunology and Molecular Genetics, Kawasaki Medical School Daiki Takezaki Department of Dermatology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yoshio Kawakami Department of Dermatology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shin-Ichiro Nishimatsu Department of Natural Sciences, Kawasaki Medical School Yutaka Ohsawa Department of Neurology, Kawasaki Medical School Yoshihide Sunada Department of Neurology, Kawasaki Medical School Tomoyuki Mukai Department of Immunology and Molecular Genetics, Kawasaki Medical School Psoriasis is a chronic inflammatory skin disease closely associated with obesity and metabolic dysfunction. While excess adiposity is considered a key risk factor, the independent contribution of body composition to psoriatic inflammation remains unclear. Myostatin negatively regulates skeletal muscle growth, and its inhibition leads to muscle hypertrophy and reduced adiposity. In this study, we investigated whether altered body composition due to impaired myostatin function affects imiquimod (IMQ)-induced psoriasiform dermatitis. Wild-type (WT) and dominant-negative myostatin transgenic mice were fed either a normal diet or a high-fat diet (HFD) for 10 weeks, followed by topical IMQ treatment to induce dermatitis. Mutant mice exhibited increased skeletal muscle mass and reduced visceral fat compared with WT controls, indicating marked changes in body composition. In WT mice, HFD feeding increased fat mass and tended to aggravate IMQ-induced ear swelling. In contrast, no significant effect of impaired myostatin function on ear thickness, epidermal hyperplasia, or the expression of psoriasis-associated genes was detected, despite reduced visceral fat. Under the present experimental conditions, these changes in body composition were not associated with a detectable attenuation of psoriasiform skin inflammation. Our results suggest that obesity-related psoriasis is influenced by metabolic and immunological factors beyond body composition. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0021-8820 2026 Amino acid mapping–guided scaffold selection and hit identification of histidine kinase inhibitors from a virtual library of over 12 million compounds EN Teruhiko Ishikawa Graduate School of Education, Okayama University Yoko Eguchi Department of Science and Technology on Food Safety, Faculty of Biology-Oriented Science and Technology, Kindai University Toshihide Okajima SANKEN, The University of Osaka Masayuki Igarashi Institute of Microbial Chemistry (BIKAKEN) Shino Ohira Analysis Technology Center, FUJIFILM Corporation Kyosuke Tsumura Analysis Technology Center, FUJIFILM Corporation Kazumasa Sakurai High Pressure Protein Research Center, Institute of Advanced Technology, Kindai University Yoshimasa Ishizaki Institute of Microbial Chemistry (BIKAKEN) Chigusa Hayashi Institute of Microbial Chemistry (BIKAKEN) Shammi Akter Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University Jiro Nakayama Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University Chie Kohayakawa Department of Lead Exploration Units, Graduate School of Pharmaceutical Sciences, The University of Osaka Akiyoshi Tani Department of Lead Exploration Units, Graduate School of Pharmaceutical Sciences, The University of Osaka Naoki Sawa Graduate School of Education, Okayama University Takaomi Katsumoto Graduate School of Education, Okayama University Fumiya Matsumoto Graduate School of Education, Okayama University Jun-Ichi Haruta Department of Lead Exploration Units, Graduate School of Pharmaceutical Sciences, The University of Osaka Ryutaro Utsumi SANKEN, The University of Osaka Waldiomycin is a natural product originally isolated from actinomycete extracts. It inhibits histidine kinases (HKs), which are essential components of bacterial two-component signal transduction systems, by targeting the conserved H-box region and suppressing autophosphorylation. Here, we identified novel HK inhibitors using amino acid mapping (AAM)-based virtual screening. We compared the AAM descriptor of the naphthoquinone moiety of waldiomycin, which directly interacts with the H-box region, with those of approximately 12 million commercially available compounds and identified 714 candidates with similar descriptor values. From these candidates, we selected 9-hydroxy-4H-pyrido[1,2-a]pyrimidin-4-one as a promising and structurally distinct scaffold and synthesized 15 derivatives. The inhibitory activities of these derivatives were evaluated against the HKs WalK, VicK, and EnvZ. Three 4H-pyrido[1,2-a]pyrimidin-4-one derivatives (FF-054, FF-055, and FF-060) exhibited potent inhibitory activity, with IC50 values ranging from 4.39 to 259 µM. Notably, the IC50 values of these compounds increased three- to six-fold against the EnvZ S242A mutant, in which the conserved H-box residue is substituted. Furthermore, nuclear magnetic resonance (NMR) analysis using the EnvZ DHp domain (residues 223–289, encompassing the H-box region) confirmed direct interaction with this domain. Taken together, these results demonstrate that pyrido[1,2-a]pyrimidin-4-one derivatives FF-054, FF-055, and FF-060 are novel HK inhibitors that target the H-box region. This study represents the first successful application of AAM-based screening to identify HK inhibitors targeting this highly conserved region. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0140-7791 2026 Natural Variation in Brachypodium distachyon Primarily Links Lignin Reinforcement to Rhizoctonia solani Resistance EN Rozi Fernanda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Niranjan Mahadevan Tea Research Institute of Sri Lanka Megumi Watanabe Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nanami Sakata Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hidenori Matsui Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kazuhiro Toyoda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuki Ichinose Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yoshiteru Noutoshi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

American Astronomical Society Acta Medica Okayama 0004-637X 980 1 2025 Observing Supernova Neutrino Light Curves with Super-Kamiokande. V. Distance Estimation with Neutrinos 117 EN Yudai Suwa Department of Earth Science and Astronomy, The University of Tokyo Akira Harada Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS), RIKEN Masamitsu Mori Division of Science, National Astronomical Observatory of Japan Ken’ichiro Nakazato Faculty of Arts and Science, Kyushu University Ryuichiro Akaho Faculty of Science and Engineering, Waseda University Masayuki Harada Department of Physics, Okayama University Yusuke Koshio Department of Physics, Okayama University Fumi Nakanishi Department of Physics, Okayama University Kohsuke Sumiyoshi National Institute of Technology, Numazu College Roger A. Wendell Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU, WPI), Todai Institutes for Advanced Study, The University of Tokyo Neutrinos are pivotal signals in multimessenger observations of supernovae (SNe). Recent advancements in the analysis method of supernova (SN) neutrinos, especially in quantitative analysis, have significantly broadened scientific possibilities. This study demonstrates the feasibility of estimating distances to SNe using neutrinos. This estimation utilizes the direct relationship between the radius of a neutron star (NS) and the distance to the supernova, which is analogous to main-sequence fitting. The radius of an NS is determined with an approximate uncertainty of 10% through observations such as X-rays and gravitational waves. By integrating this information, the distance to the supernova can be estimated with an uncertainty of within 15% at a 95% confidence level. It has been established that neutrinos can pinpoint the direction of supernovae, and when combined with distance estimates, three-dimensional localization becomes achievable. This capability is vital for follow-up observations using multimessenger approaches. Moreover, more precise distance determinations to SNe through follow-up observations, such as optical observations, allow for accurate measurements of neutron-star radii. This data, via the neutron-star mass–radius relationship, could provide various insights into nuclear physics. No potential conflict of interest relevant to this article was reported.

Oxford University Press (OUP) Acta Medica Okayama 0032-0781 2026 Disrupted FLOWERING LOCUS C alleles from weedy radish enhance the florigenic potential of rootstocks for graft-mediated floral induction in Brassicaceae pcag119 EN Ko Motoki Graduate School of Environmental, Life and Natural Science and Technology, Okayama University Saki Kobayashi Graduate School of Environmental, Life and Natural Science and Technology, Okayama University Kazusa Nishimura Graduate School of Environmental, Life and Natural Science and Technology, Okayama University Yu Kinoshita Graduate School of Agriculture, Kyoto University Makoto Kashima Faculty of Science, Department of Biomolecular Science, Toho University Koichiro Ushijima Graduate School of Environmental, Life and Natural Science and Technology, Okayama University Tanjuro Goto Graduate School of Environmental, Life and Natural Science and Technology, Okayama University Ken-ichiro Yasuba Graduate School of Environmental, Life and Natural Science and Technology, Okayama University Munetaka Hosokawa Faculty of Agriculture, Kindai University Graft-mediated floral induction is a classical yet promising breeding technique that accelerates seed production and shortens generation time in crops. However, its application remains limited to a few species because floral induction is often unstable. Even among florally induced rootstocks, grafted scions can differ in their flowering response depending on rootstock genotype, but the genetic basis of this variation remains unclear. Here, using a Brassicaceae grafting model, we investigated two early-bolting radish (Raphanus sativus) accessions differing in their ability to induce flowering. We focused on a significant difference in FLOWERING LOCUS T (FT) expression between these accessions and identified two quantitative trait loci (QTLs) associated with FT levels. Transcriptomic and genomic analyses revealed that both QTLs harbored previously unreported disrupted alleles of FLOWERING LOCUS C (FLC) homologs, key floral repressors involved in vernalization, which showed reduced expression and produced defective transcripts. Grafting experiments demonstrated that these disrupted FLC alleles enhanced floral induction, with RsFLC1 having a major effect. Our results indicate that the FT expression threshold required for graft-mediated floral induction is higher than that for rootstock flowering itself and that this threshold is reached when FLC-mediated repression is substantially reduced. These alleles were inferred to have originated from weedy radish (Raphanus raphanistrum), likely contributing to early flowering in disturbed environments. This study suggests that exploring genetic variations in FT expression is an effective strategy to develop highly florigenic rootstocks, thereby broadening the application of graft-mediated floral induction in crop breeding. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 2751-1219 5 9 2026 Proton‐Radiation‐Tolerant Silicon Photonic Charge Sensor for Spacecraft Applications e70208 EN Wataru Takahama Department of Physics and Electronics, Osaka Metropolitan University Kosei Otsuka Department of Physics and Electronics, Osaka Metropolitan University Ayumi Ishihara Department of Physics and Electronics, Osaka Metropolitan University Rikuto Hojo Department of Space Systems Engineering, Kyushu Institute of Technology Tomofumi Mogami ElectrostaticEngineering DEPT, Kasuga Denki INC Kazuhiro Toyoda Department of Space Systems Engineering, Kyushu Institute of Technology Kohtaku Suzuki Research and Development, The Wakasa Wan Energy Research Center Yasushi Takahashi Faculty of Environmental, Life, Natural Science and Technology,Okayama University Silicon 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.

American Physical Society (APS) Acta Medica Okayama 0031-9007 137 9 2026 Strain-Tuned Nodal Superconductivity in the Charge-Ordered Kagome Metal CsV3⁢Sb5 096003 EN Yusuke Takeuchi Department of Physics, Okayama University Akito Kobayashi Department of Physics, Okayama University Saki Uchida Department of Physics, Okayama University Takumi Nagao Department of Physics, Okayama University Seigo Ogawa Department of Physics, Okayama University Rui Zhou Institute of Physics, Chinese Academy of Sciences, and Beijing National Laboratory for Condensed Matter Physics Shinji Kawasaki Department of Physics, Okayama University Fei Song Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering, College of Physics and Energy, Fujian Normal University Hao Ni Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering, College of Physics and Energy, Fujian Normal University Yong Zhao Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering, College of Physics and Energy, Fujian Normal University Guo-qing Zheng Department of Physics, Okayama University The nature of the superconducting pairing symmetry in the kagome metal CsV3⁢Sb5 and its relationship with the charge density wave (CDW) order are central unresolved issues. Here, we investigate the evolution of superconductivity in CsV3⁢Sb5 under in situ uniaxial pressure using 121Sb nuclear quadrupole resonance (NQR). We find that tensile strain significantly enhances the superconducting transition temperature, 𝑇c, while the CDW remains unchanged, demonstrating that superconductivity can be tuned independently of the bulk charge order. At a tensile strain of 𝜖 =+0.90%, the nuclear spin-lattice relaxation rate reveals a remarkable double transition: an upper transition at 𝑇c⁢1=3.6  K to a nodal gap state, and a lower one at 𝑇c⁢2=3.0  K characterized by a nodeless gap. These results evidence degenerate superconducting states with different gap symmetry in the kagome metal at ambient pressure which split under strain. Our Letter demonstrates a high tunability of superconductivity by uniaxial pressure. No potential conflict of interest relevant to this article was reported.

Japan Medical Association Acta Medica Okayama 2433-3298 8 2 2025 Unraveling Causality: Innovations in Epidemiologic Methods 323 337 EN Etsuji Suzuki Department of Epidemiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University For several decades, the counterfactual model and the sufficient cause model have shaped our understanding of causation in biomedical science and, more recently, the link between these two models has enabled us to obtain a deeper understanding of causality. In this article, I provide a brief overview of these fundamental causal models using a simple example. The counterfactual model focuses on one particular cause or intervention and gives an account of the various effects of that cause. By contrast, the sufficient cause model considers sets of actions, events, or states of nature which together inevitably bring about the outcome under consideration. In other words, the counterfactual framework addresses the question “what if?” while the sufficient cause framework addresses the question “why does it happen?” Although these two models are distinct and address different causal questions, they are closely related and used to elucidate the same cause-effect relationships. Importantly, the sufficient cause model makes clear that causation is a multifactorial phenomenon, and it is a “finer” model than the counterfactual model; an individual is of one and only one response type in the counterfactual framework, whereas an individual may be at risk of none, one, or several sufficient causes. Understanding the link between the two causal models can provide greater insight into causality and can facilitate the use of each model in appropriate contexts, highlighting their respective strengths. I will briefly present three topics of interest from our research: the relationship between the concepts of confounding and of covariate balance; distinctions between attributable fractions and etiologic fractions; and the identification of operating mediation and mechanism. It is important to scrutinize observed associations in a complementary manner, using both the counterfactual model and the sufficient cause model, employing both inductive and deductive reasoning. This holistic approach will better help us to unravel causality. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2311-5521 11 9 2026 First-Order Wall-Slip-Induced Departure from Inverse-Cubic Scaling of Levitation-Pressure RMS in a Push–Pull Levitation Stage 218 EN Eisuke Umesaki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hiroki Suzuki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Junji Sakamoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Toshinori Kouchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University This study clarifies how rarefaction-induced wall slip in a thin gas film affects the established inverse-cubic scaling law for the spatial nonuniformity of levitation pressure in a push–pull levitation stage. The levitation force in this stage is generated by the combined action of blowing and suction. The continuum-based stress description is retained, and only the wall boundary condition is changed from the no-slip condition to a first-order slip condition. Three-dimensional incompressible unsteady Stokes simulations in a thin-gap unit-cell model are combined with a lubrication-theory scaling analysis. The effects of levitation height, blowing-velocity distribution, port-radius ratio, and computational-domain width are examined systematically. The results show that wall slip has only a minor influence at relatively large levitation heights. As the levitation height decreases, however, rarefaction-induced slip increases the flow-rate conductance. Consequently, the intensity of the spatial variation in levitation pressure is systematically reduced below that predicted by the no-slip inverse-cubic scaling law. This departure is well described by a correction relation derived from the lubrication approximation and remains robust against changes in the prescribed blowing-velocity distribution and geometric conditions. These findings provide an incompressible baseline for predicting levitation-pressure nonuniformity within the nominal gap-based Knudsen-number range examined here. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2073-4395 16 16 2026 Genetic Dissection and Fine-Mapping of QTL for Salinity Tolerance at the Reproductive Stage on Chromosome 2 of Rice Variety Nona Bokra 1518 EN Farjana Rauf Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tran Thi Thu Hien Graduate School of Environmental and Life Science, Okayama University Nguyen Thi Thu Thuy Graduate School of Environmental and Life Science, Okayama University Asami Tomita Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yoshihiko Hirai Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Soil salinity is a major constraint limiting rice productivity, particularly at the reproductive stage. To elucidate the genetic basis of reproductive stage salinity tolerance, this study validated and fine-mapped quantitative trait loci (QTL) for yield-related traits using a salinity-tolerant line SL506, identified through screening of Nona Bokra–CSSLs in a Koshihikari background. In 2016, the F2 population derived from SL506/Koshihikari was evaluated under long-term salt stress; three QTLs associated with plant dry weight, panicle number, and grain weight were detected on chromosome 2. In 2023, validation analysis using F3 individuals confirmed the presence of these QTLs. Subsequent fine-mapping using F4 near-isogenic lines (NILs) delimited the QTL to a 1.7 Mb interval and high-resolution mapping using an F5 recombinant population progressively refined it to a 473 kb genomic region containing 69 annotated genes. Variant Effect Predictor analysis identified 15 deleterious nonsynonymous variants (SIFT < 0.05) in six candidate genes. Based on annotated gene functions, predicted variant effects, and their membership in stress-related gene families, OsPP2C24, OsFbox102, and OsWAK14 were suggested as the most promising candidate genes underlying qPDW2. These findings provide insights into the genetic basis of reproductive-stage salinity tolerance from valuable resources for the future improvement of salt tolerance and yield stability in rice. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2673-7655 6 2 2026 Effects of Different Heading Dates on Agronomic and Yield-Related Traits Under Salt Stress in Rice 28 EN Sadia Afrin Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Sayuri Ito School of Agriculture, Okayama University M M Emam Ahmed Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Shuto Ogino School of Agriculture, Okayama University Asami Tomita Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yoshihiko Hirai Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Salinity is a major abiotic stress limiting rice production worldwide. This study aims to elucidate the effects of heading date on salt tolerance in rice. Five near-isogenic lines (NILs) developed from the SL2038/Koshihikari backcross population were grown with or without salt stress. SL2038 is a salt-tolerant line with delayed heading (~18 days) compared to the salt-sensitive background Koshihikari. The results showed that late-heading NILs produced significantly higher plant dry weight, panicle weight, percentage of filled grains, and grain weight (p < 0.05) under long-term salt stress. In Koshihikari, which exhibited delayed heading due to long-day treatment, the percentage of white heads was low, and panicle and grain weights were significantly higher under salt stress. Experiments with different sowing times indicated that late heading, such as sowing in June, resulted in higher grain weights. This is the first report to assess the impact of heading date on agronomic and yield-related traits under salt stress. In conclusion, even with a prolonged salt treatment period, heading during periods of low temperature and solar radiation results in higher grain weight under salt stress. This is proposed as one of the strategies for salt escape. These findings can be used to improve rice yield and implement crop management in salt-affected regions. No potential conflict of interest relevant to this article was reported.

Walter de Gruyter GmbH Acta Medica Okayama 2294-1932 2026 Direct evidence for water-filled yet hydraulically isolated xylem vessels in two temperate tree species 1 14 EN Mayumi Y. Ogasa Kansai Research Center, Forestry and Forest Products Research Institute Yasuhiro Utsumi Ashoro Research Forest, Kyushu University Kenichi Yazaki Hokkaido Research Center, Forestry and Forest Products Research Institute Naoko H. Miki Faculty of Environmental, Life, Natural Science and Technology Kenji Fukuda Graduate School of Agricultural and Life Sciences, The University of Tokyo Xylem vessels in sapwood are typically interpreted as either conductive or non-functional following embolism or occlusion, implicitly assuming that the presence of water within the lumen reflects participation in the transpiration stream. However, the relationship between lumen water content and hydraulic connectivity has rarely been examined directly at the cellular level. In this study, we combined cryo-scanning electron microscopy and fluorescence microscopy to compare lumen water status with hydraulic connectivity on the same xylem surface in current-year xylem of Carpinus tschonoskii and Aria alnifolia, using tension-driven dye uptake to identify conductive vessels. Most vessels were stained and water-filled, consistent with functional conduits, whereas unstained gas-filled vessels corresponded to embolized conduits. Notably, certain vessels retained water despite lacking dye signals, indicating hydraulic isolation from the conductive xylem network. Although these vessels represented a minor fraction of the conduit population, their occurrence suggests that the traditionally binary classification should be expanded to incorporate an additional conduit function. These vessels were observed in both species, suggesting that hydraulically disconnected vessels represent a common phenomenon across species. These findings reveal previously underrecognized heterogeneity in xylem hydraulic organisation and demonstrate that conduit status cannot always be inferred from the presence of water alone. Recognising this intermediate condition refines current interpretations of xylem function and highlights the value of integrating high-resolution imaging with hydraulic measurements. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1058-8388 2026 MIT/TFE family transcription factors, Mitf and Tfec, redundantly promote pigment cell differentiation and retinal epithelium pigmentation in teleosts 1 15 EN James Lister Department of Human and Molecular Genetics and Massey Cancer Center, Virginia Commonwealth University School of Medicine Keisuke Sugiwaka Department of Biological Science, Division of Natural Science, Graduate School of Science, Nagoya University Tetsuaki Kimura Department of Basic Biology, School of Life Science, Graduate University of Advanced Studies (SOKENDAI) & Laboratory of Bioresources, National Institute for Basic Biology Rieko Tanaka World Medaka Aquarium, Nagoya Higashiyama Zoo and Botanical Gardens Makoto Goda Institute of Photonics Medicine, Hamamatsu University School of Medicine Hikaru Kobayashi Department of Biological Science, Division of Natural Science, Graduate School of Science, Nagoya University Chikako Inoue R&D Fish Breeding Group, Regional Fish Institute, Ltd. Kawilarang W. A. Masengi Faculty of Fisheries and Marine Science, Sam Ratulangi University Kazunori Yamahira Tropical Biosphere Research Center, University of the Ryukyus Kiyoshi Naruse Department of Basic Biology, School of Life Science, Graduate University of Advanced Studies (SOKENDAI) & Laboratory of Bioresources, National Institute for Basic Biology Satoshi Ansai Ushimado Marine Institute, Graduate School of Natural Science and Technology, Okayama University Robert N. Kelsh Department of Life Sciences, University of Bath Masahiko Hibi Department of Biological Science, Division of Natural Science, Graduate School of Science, Nagoya University Hisashi Hashimoto Department of Biological Science, Division of Natural Science, Graduate School of Science, Nagoya University Background: Transcription factors of the MIT/TFE family—mitfa, mitfb, and tfec—play essential roles in specifying pigment cells derived from neural crest cells in vertebrates. In teleosts, which possess multiple pigment cell types, these factors exhibit partially redundant but largely distinct functions across different pigment lineages. We previously reported that the combined loss of mitfa and mitfb leads to a complete absence of melanophores, xanthophores, and leucophores in medaka.<br> Results: Here, we describe newly generated hypomorphic alleles of mitfa and mitfb, which result in delayed melanophore development. Using these hypomorphic mutants in combination with a newly generated null allele of tfec, we show that Tfec can partially compensate for the loss of Mitfa and Mitfb in melanophore, xanthophore, and leucophore differentiation. Consistent with previous findings in zebrafish, loss of tfec alone results in the complete absence of iridophores. Importantly, simultaneous null mutations in all three genes cause a complete loss of all four chromatophore types and lead to defective pigmentation of the retinal pigmented epithelium (RPE), which is not derived from the neural crest in both Oryzias species and in zebrafish. Using an RPE-specific marker, we further show that the RPE is specified and structurally intact but fails to melanize.<br> Conclusions: These findings indicate that the redundant functions of Mitfa, Mitfb, and Tfec are not only essential for the specification of diverse pigment cell types but also critical for RPE pigmentation. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1345-2630 2026 Macroscopic and microscopic visualization of Pseudomonas syringae pv. tabaci infection using complementary bioluminescent and fluorescent reporter systems EN Kana Kuroe Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nanami Sakata Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yasuhiro Ishiga Faculty of Life and Environmental Sciences, University of Tsukuba Yoshiteru Noutoshi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kazuhiro Toyoda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuki Ichinose Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hidenori Matsui Graduate School of Environmental, Life, Natural Science and Technology, Okayama University The development of bioluminescent and fluorescent reporter systems has enabled visualization of plant-pathogenic bacterial infection dynamics, providing insights into detailed mechanisms of infection and potential applications for disease control. Pseudomonas syringae pv. tabaci 6605 (Pta) possesses quorum sensing systems and produces fluorescent pigments, which make it difficult to directly apply commonly used reporter systems. In this study, we first constructed a homologous recombination-based genomic insertion system for stable chromosomal integration of reporter genes in Pta. Using this system, we established a LuxCDABE bioluminescent system driven by the nptII promoter, which successfully enabled macroscale tracking of bacterial populations during infection. We then attempted to construct an sGFP fluorescent reporter using the same nptII promoter. However, the endogenous autofluorescence of Pta masked the sGFP signal, making quantitative detection difficult. To overcome this autofluorescence problem, we screened constitutively highly expression promoters based on transcriptome data and identified two effective promoters suitable for fluorescent monitoring of Pta infection. Together with the LuxCDABE system, this integrated platform provides comprehensive spatiotemporal analysis of virulence mechanisms and plant defense responses in the Pta pathosystem, with potential applicability to other plant-pathogenic bacteria. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2041-1723 17 1 2026 RNase-mediated defence and its association with SCCmec in Staphylococcus aureus 9986 EN Kohei Kondo Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Japan Institute for Health Security Aa Haeruman Azam Department of Drug Development, National Institute of Infectious Diseases, Japan Institute for Health Security Junzo Hisatsune Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Japan Institute for Health Security Shinjiro Ojima Department of Drug Development, National Institute of Infectious Diseases, Japan Institute for Health Security Kotaro Chihara Department of Drug Development, National Institute of Infectious Diseases, Japan Institute for Health Security Tomohiro Nakamura Department of Drug Development, National Institute of Infectious Diseases, Japan Institute for Health Security Azumi Tamura Department of Drug Development, National Institute of Infectious Diseases, Japan Institute for Health Security Wakana Yamashita Department of Drug Development, National Institute of Infectious Diseases, Japan Institute for Health Security Satoshi Nakano Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Japan Institute for Health Security Shoko Kutsuno Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Japan Institute for Health Security Yo Sugawara Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Japan Institute for Health Security Jumpei Uchiyama Department of Bacteriology, Graduate School of Medicine Dentistry and Pharmaceutical Sciences, Okayama University Masayuki Amagai Department of Dermatology, Keio University School of Medicine Tetsuo Yamaguchi Department of Microbiology and Infectious Diseases, Toho University School of Medicine Yoshikazu Ishii Department of Microbiology and Infectious Diseases, Toho University School of Medicine Koichi Watashi Department of Drug Development, National Institute of Infectious Diseases, Japan Institute for Health Security Yoshimasa Takahashi Research Center for Vaccine Development, National Institute of Infectious Diseases, Japan Institute for Health Security Kotaro Kiga Department of Drug Development, National Institute of Infectious Diseases, Japan Institute for Health Security Motoyuki Sugai Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Japan Institute for Health Security The rise of antibiotic resistance in Staphylococcus aureus is a major threat to global health. Resistance often emerges when bacteria acquire foreign DNA elements, such as the SCCmec cassette that makes strains resistant to nearly all β-lactam antibiotics. Yet, not all S. aureus lineages take up these elements equally, raising the question of what prevents some strains from becoming drug-resistant. Here we identify a previously unknown defence factor that explains this mystery in a common skin lineage (ST188), frequently isolated from patients with atopic dermatitis. Such defence factor is encoded by a gene, which we name sadR, that is present in methicillin-susceptible ST188 strains but absent from resistant counterparts. SadR exhibits RNase activity that provides anti-bacteriophage and anti-plasmid defence, thus acting as a barrier to the uptake of mobile genetic elements. Gene sadR is found in methicillin-susceptible strains in S. aureus lineages other than ST188, and is consistently located adjacent to rlmH, the canonical SCCmec integration site. Moreover, SadR homologues are widespread across staphylococci and other bacteria suggesting a previously unrecognised family of RNase-based defence systems. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 8756-758X 2026 Fatigue Life Evaluation Using the Damage‐Equivalent Strain for 7075‐T6 Aluminum Alloy Under Bending and Torsion Bending Vibrations EN Junji Sakamoto Faculty of Environmental, Life, Natural Science and Technology, Okayama University Naoya Tada Faculty of Environmental, Life, Natural Science and Technology, Okayama University Takeshi Uemori Faculty of Environmental, Life, Natural Science and Technology, Okayama University The 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.

Elsevier BV Acta Medica Okayama 0739-7240 98 2027 Transcriptional remodeling of local thyroid hormone metabolism is associated with feather growth termination in chicken wing feathers 107057 EN Masamichi Shinohara Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuri Nozawa Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hibiki Fukuchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yu Takeuchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Sayaka Aizawa Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Sakae Takeuchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Feather elongation is sustained by continuous cell proliferation within the feather follicle; however, the molecular mechanisms responsible for feather growth termination remain poorly understood. In this study, we investigated molecular changes associated with feather growth termination by comparing two chicken wing feather types with contrasting growth characteristics: primary wing feathers and primary coverts. Histological and bromodeoxyuridine incorporation analyses demonstrated that primary wing feathers remained in an active growth phase, whereas primary coverts exhibited pulp regression, reduced cell proliferation, and characteristics of growth termination. Gene expression analyses showed that primary coverts exhibited reduced expression of prolactin receptor (PRLR), type 2 iodothyronine deiodinase (DIO2), and insulin-like growth factor 2 (IGF2), together with marked induction of the thyroid hormone (TH)-inactivating enzyme type 3 iodothyronine deiodinase (DIO3). In contrast, primary wing feathers exhibited relatively higher expression of PRLR, DIO2, and IGF2 than primary coverts, while maintaining consistently low DIO3 expression. Reporter assays showed increased IGF2 promoter activity following triiodothyronine (T3) treatment in all three independent experiments, although the increase did not reach statistical significance. Thus, the reporter assay provides only tentative support for T3 responsiveness of the IGF2 promoter, consistent with our previous in vivo and primary-culture findings showing T3-dependent increases in IGF2 expression. These coordinated transcriptional changes are consistent with remodeling of local TH metabolism during the transition from active feather growth to growth termination. While local TH concentrations and direct deiodinase activities remain to be quantified, and the causal relationship between PRL/PRLR signaling and DIO3 induction remains unresolved, this study provides a molecular framework for understanding how local endocrine regulation translates systemic hormonal signals into feather type-specific growth responses during avian feather development. Graphical abstract No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 1010-6030 478 2026 Deep-blue solid-state emission from Ternaphthalene: Photophysical tuning via multi-chromophore architectures 117156 EN Minoru Yamaji Division of Molecular Science, Graduate School of Science and Engineering, Gunma University Kengo Suzuki Hamamatsu Photonics K.K. Hideki Okamoto Department of Chemistry, Faculty of Environment, Life, Natural Sciences and Technology, Okayama University We report the synthesis and photophysical characterization of a series of “all-naphthalene” multi-chromophore systems, ternaphthalenes (TNps), designed for efficient deep-blue solid-state emission. Unlike planar polycyclic aromatic hydrocarbons that suffer from aggregation-caused quenching (ACQ), the twisted molecular architecture of TNps effectively inhibits π-π stacking interactions. Consequently, several TNps exhibit crystallization-induced emission enhancement (CIEE) or retain high quantum yields (up to 0.94) in the solid state. Kinetic analysis revealed that this efficiency stems from the significant suppression of non-radiative rates (knr) due to the restricted intramolecular rotation in the rigid crystal lattice. Furthermore, a decisive topological effect on the radiative rate (kf) was demonstrated. The 1,4-, 1,5- and 2,6-linked isomers display allowed transitions with large oscillator strengths (f) and fast radiative rate (kf = ca. 5 × 108 s−1), whereas the 2,7-linked isomers exhibit forbidden-like character with prolonged lifetimes. A distinct linear correlation between the experimental and calculated values empirically supports the applicability of the Strickler-Berg relationship in both solution and solid states. These findings demonstrate that controlling the chromophore connectivity is a powerful strategy to tune excited-state dynamics for developing high-performance deep-blue organic emitters. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 2367-0932 10 3 2026 Substitution‐Dependent Modulation of Photophysical Properties of 2,7‐ and 3,6‐Dinaphthyl‐9‐phenylcarbazoles in Solution and Solid State e202500335 EN Minoru Yamaji Division of Molecular Science, Graduate School of Science and Engineering, Gunma University Tadashi Mori Research Center for Environmental Preservation and Graduate School of Engineering, The University of Osaka Hideki Okamoto Department of Chemistry, Faculty of Environment, Life, Natural Sciences and Technology, Okayama University The photophysical properties of two positional isomers of dinaphthyl-9-phenylcarbazoles (2,7-DNpPCz and 3,6-DNpPCz) were systematically investigated in solution and solid states. Experimental measurements revealed a pronounced positional dependence, although both compounds exhibit fluorescence in solution and the solid state. On average, the 2,7-isomers exhibit larger fluorescence rate values than the 3,6-isomers, although the magnitude of this difference varies among individual compounds. To gain mechanistic insight, density function theory (DFT) and time-dependence DFT calculations were performed at the (TD)-B3LYP/6-31+G(d) level. The results show that 2,7-DNpPCz derivatives possess delocalized frontier orbitals and large oscillator strengths for the S1 ← S0 transition, whereas 3,6-DNpPCz derivatives exhibit smaller oscillator strengths with mixed orbital contributions, leading to weaker transition probabilities. These combined findings demonstrate that substitution geometry critically governs radiative decay dynamics in carbazole-based luminophores and provide valuable guidelines for the molecular design of efficient solid-state organic emitters. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2238-7854 45 2026 Enhancement of mechanical properties in a cast hypereutectic Al–Si alloy via rapid cooling in heated mold continuous casting 485 494 EN Shuhei Takeuchi Graduate School of Environment, Life, Natural Science and Technology, Okayama University Shota Nakagawa UACJ Corporation Yoshifumi Shinzato UACJ Corporation Tadashi Minoda UACJ Corporation Naotaka Ohtsuka UACJ Corporation Mitsuhiro Okayasu Department of Mechanical and Systems Engineering, Okayama University To 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 BV Acta Medica Okayama 0005-2728 1868 1 2027 Structural and functional analysis of a photosystem II mutant PsbA3-S264V 149607 EN Songbo Fan Advanced Research Field, Research Institute for Interdisciplinary Science, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yoshiki Nakajima Advanced Research Field, Research Institute for Interdisciplinary Science, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Koji Kato Advanced Research Field, Research Institute for Interdisciplinary Science, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haowei Jiang Advanced Research Field, Research Institute for Interdisciplinary Science, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Pi-Cheng Tsai Advanced Research Field, Research Institute for Interdisciplinary Science, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Anqi Jia Advanced Research Field, Research Institute for Interdisciplinary Science, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Miwa Sugiura Proteo-Science Research Center, Ehime University Jian-Ren Shen Advanced Research Field, Research Institute for Interdisciplinary Science, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Photosystem II (PSII) catalyzes water oxidation and oxygen evolution by a light-induced electron transfer chain, leading to the generation of electrons, protons and dioxygen. D1-S264 is a residue located close to the QB-binding site, and mutation of this residue has been shown to bring significant effects on the electron transfer and oxygen-evolving activities. Here we analyzed the structure of a Thermosynechococcus elongatus mutant PsbA3-S264V by cryo-electron microscopy at 1.96 Å resolution, which showed significant changes in the structure surrounding the bicarbonate and QB-binding region. Due to change of Ser to Val, the hydrogen-bond between the QB carbonyl oxygen and S264 is altered, which changed the protonation pathway of QB from the original route of D1-H252 through D1-S264 to QB, to a new, longer and less efficient route of D1-H252 through D1-F265 to QB. Two residues, D1-E244 and D2-E242, changed their side chain orientations significantly. Among them, D2-E242 adopted two conformations, and both are largely deviated from the original structure. All these changes led to alterations in hydrogen-bonding networks of two channels, channel A and channel B, that connect the stromal surface to QB and may function to transport protons to protonate QB. Furthermore, isothermal titration calorimetry experiments showed a diminished 3-(3,4-dichlorophenyl)-1, 1-dimethylurea (DCMU) binding affinity of the mutated PSII, which may be explained by a structural rotation of D1-F255 in the mutant based on structural analysis of DCMU-bound PSII. These findings offer valuable insights into the functions of D1-S264 in QB protonation and function, as well as in the DCMU-binding. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1477-0520 2026 Stereoselective synthesis of β,β-diborylalanine (AlaBB) and its incorporation into oligopeptides EN Naoyuki Nitta Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kenshin Nakai Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haruki Mizoguchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Akira Sakakura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University We report the stereoselective synthesis of β,β-diborylalanine (AlaBB), a compact amino acid scaffold designed to introduce a gem-diboronic acid motif as a branched connector in peptides. Pinacol-protected AlaBB derivatives, denoted as AlaBB(pin)2, were prepared from an Ellman imine, incorporated into short peptides, and converted to the corresponding gem-diboronic acid form. No potential conflict of interest relevant to this article was reported.

American Society for Microbiology Acta Medica Okayama 2165-0497 14 8 2026 High-throughput screening system for antimycobacterial compounds using in vitro infected cells: construction and application to compounds in the Ōmura Natural Compound Library e00484-26 EN Takemasa Takii Department of Mycobacterium Reference and Research, The Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association Aoi Kimishima Ōmura Satoshi Memorial Institute, Kitasato University Masato Iwatsuki Ōmura Satoshi Memorial Institute, Kitasato University Yoshihiro Watanabe Ōmura Satoshi Memorial Institute, Kitasato University Naoya Ohara Department of Oral Microbiology, Graduate School of Medicine, Density and Pharmaceutical Sciences, Okayama University Yukihiro Asami Ōmura Satoshi Memorial Institute, Kitasato University The global increase in multidrug-resistant tuberculosis strains poses a major threat; consequently, there is an urgent need to identify and develop novel drugs. We have previously presented a simple fibroblast assay (SFA) screening method that enables the simultaneous assessment of antibacterial activity and cytotoxicity toward host cells. This method was developed based on our finding that live (but not dead) Mycobacterium tuberculosis bacilli exhibit cytotoxic activity against human lung fibroblasts, and that this cytotoxicity, which is proportional to the number of viable bacterial cells, is inhibited by known antimycobacterial drugs. While conventional methods to measure M. tuberculosis growth require 2–4 weeks to detect antibacterial activity; the SFA method enables detection within 2–3 days and can detect compounds that are active within host cells. Here, we applied high-throughput screening, based on assessment of cytotoxicity, to identify candidate antimycobacterial agents. In parallel, by comparing the direct antibacterial activity of compounds in liquid medium (using the broth dilution test) with that observed via SFA, we developed a new SFA-based screening system to select compounds with low cytotoxicity that are active outside or inside the host cells. Using this dual system, we screened 742 compounds from the Ōmura Natural Compound Library (Kitasato University, Japan), with 62 hits. Of these, 19 were excluded owing to their toxicity, and six exhibited antibacterial activity only via SFA screening. Four promising antimycobacterial candidates with no cytotoxicity at the 10 μg/mL threshold—aridicin A, lankamycin, streptovaricin, and lariatin A—were identified. identified.This novel system supports the rapid identification of low-cytotoxicity antimycobacterial compounds that are active inside or outside the host cells. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1477-0520 2026 Stereoselective synthesis of β,β-diborylalanine (AlaBB) and its incorporation into oligopeptides EN Naoyuki Nitta Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kenshin Nakai Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haruki Mizoguchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Akira Sakakura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University We report the stereoselective synthesis of β,β-diborylalanine (AlaBB), a compact amino acid scaffold designed to introduce a gem-diboronic acid motif as a branched connector in peptides. Pinacol-protected AlaBB derivatives, denoted as AlaBB(pin)2, were prepared from an Ellman imine, incorporated into short peptides, and converted to the corresponding gem-diboronic acid form. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2590-1230 32 2026 Prediction of tool-path and cycle time errors of CNC machining using a transformer-based deep learning model 112872 EN Kazuki Kaneko Graduate School of Environmental, Life, Natural Science and Tech, Okayama University Zongze Li Graduate School of Advanced Science and Engineering, Hiroshima University The prediction of tool-path and cycle time errors of computer numerical control (CNC) machining is important in manufacturing field. In this study, these errors are considered as sequential data corresponding to the lines of G-code, i.e., the error prediction is a sequence-to-sequence task, and a Transformer-based deep learning model was constructed to predict the tool-path and cycle time errors simultaneously, taking the positional increments and feed rate as the input. The training datasets were created by running a randomly generated G-code on a real CNC machine tool and subsequently tracking the actual errors, where the motion and feed rate are stochastically defined. The model is validated by conducting the error prediction on six sets of G-code. In addition, the comparison with a Bi-LSTM-based deep learning model is conducted. The results show that the prediction accuracy of the Transformer model can achieve the mean prediction accuracies of ±1 μm and ±1 ms in tool-path and cycle time error predictions, respectively. Furthermore, the Transformer model has a smaller prediction uncertainty than the Bi-LSTM model. Compared with conventional methods only analyzing tool-path errors or cycle-time errors, the utilized model has an advantage in its ability to simultaneously predict tool-path errors and cycle time errors. No potential conflict of interest relevant to this article was reported.

Oxford University Press (OUP) Acta Medica Okayama 0366-7022 54 6 2025 Vesicle-combined PtBi/C catalyst for base-free conversion of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid upaf104 EN Toshinori Shimanouchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Koji Deguchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kazuma Yasuhara Division of Materials Science, Nara Institute of Science and Technology (NAIST) Yukitaka Kimura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University A conversion of 5-hydroxymethylfurfural to 2,5-frandicarboxylic acid (FDCA) was catalyzed by using a catalyst of PtBi-activated carbon (PtBi/C) combined with vesicles made of phospholipid. No alteration of the electron state of the PtBi/C by vesicles was observed. However, FDCA was obtained under mild-temperature and base-free conditions. The yield of FDCA depended on the hydration nature of vesicles. It was therefore suggested that vesicles gave bound water as a novel driving force for the reaction. The present finding would explore an application of vesicles to new catalytic reactions that are different from conventional biochemical reactions. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0376-7388 757 2026 Multi-criteria evaluation of graphene oxide nanofiltration membranes for decaffeination 125992 EN Yihan Tian School of Materials Science and Engineering, University of New South Wales Tongxi Lin School of Materials Science and Engineering, University of New South Wales Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Xiaojun Ren School of Materials Science and Engineering, University of New South Wales Rakesh Joshi School of Materials Science and Engineering, University of New South Wales Nanofiltration (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.

MDPI AG Acta Medica Okayama 1660-3397 24 9 2026 A Marine Brevibacillus-Derived Membrane-Lytic Peptide: Molecular Insight and Biophysical Characterization of a Novel AMP, FNL62-AMP 309 EN Namfa Sermkaew School of Pharmacy, Walailak University Apichart Atipairin School of Pharmacy, Walailak University Sucheewin Krobthong Center of Excellence in Natural Products Chemistry (CENP), Department of Chemistry, Faculty of Science, Chulalongkorn University Chanat Aonbangkhen Center of Excellence in Natural Products Chemistry (CENP), Department of Chemistry, Faculty of Science, Chulalongkorn University Yodying Yingchutrakul National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency Jumpei Uchiyama Department of Infectious Diseases, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Nuttapon Songnaka School of Pharmacy, Walailak University This study characterizes the genomic identity, functional efficacy, and computational biophysics of FNL62-AMP, a novel antimicrobial peptide isolated from a phylogenomically distinct, newly identified Brevibacillus species. Production kinetics revealed a late-exponential phase onset of antibacterial activity with sustained potency against methicillin-resistant Staphylococcus aureus (MRSA). LC-MS/MS analysis identified the peptide sequence as NH2-LLLLFR-COOH. FNL62-AMP demonstrated excellent formulation resilience, retaining full anti-MRSA activity under high thermal stress (80 °C for 6 h) and showing robust resistance to generic trypsin and proteinase K proteolysis. Formulative co-incubation assays demonstrated charge-dependent compatibility, where nonionic Triton X-100 preserved baseline efficacy while ionic surfactants induced antagonism. In vitro time-kill kinetics, scanning electron microscopy, and SYTOX Green assays confirmed rapid, concentration-dependent bactericidal action driven by immediate membrane permeabilization. Molecular dynamics simulations successfully captured the spontaneous self-assembly of 64 FNL62-AMP monomers into a stable macro-aggregate. This consolidation process was quantitatively characterized by a simultaneous contraction in the radius of gyration (Rg), a sharp drop in solvent-accessible surface area (SASA), and a transitional plateau in mean squared displacement (MSD). Ultimately, the high thermal stability, structural resilience, and predictable surfactant compatibility of FNL62-AMP propose ways to be developed for lead optimization and druggability. No potential conflict of interest relevant to this article was reported.

Fuji Technology Press Ltd. Acta Medica Okayama 1883-8022 20 5 2026 Real-Time Estimation of Temperature Field and Thermal Displacement in Machine Tool Linear Motion Systems Using Servo Data 466 477 EN Ryoji Kondo YASDA PRECISION TOOLS K.K. Kazuhito Ohashi Faculty of Environmental, Life, Natural Science and Technology, Okayama University Heat generated in machine tools during operation causes thermal deformation and deteriorates machining accuracy. To suppress thermal deformation and the resulting displacement, strategies such as reducing heat generation, cooling machine elements that generate heat, and compensating for thermal displacement are generally adopted. However, existing methods for estimating and compensating for thermal deformation and displacement can only be adopted in limited situations. In particular, there are few reports on real-time estimation methods that take into account moving parts and actual machine operating conditions. For high-accuracy machining, it is important to understand the temperature field and the associated displacement. In this study, real-time estimation of the temperature field and displacement is carried out on a test apparatus equipped with a ball screw drive system and a linear guideway system. In the estimation process, heat generation values are first calculated from servo data corresponding to the machine operation. Using these calculated values, the temperature field is then derived through the finite volume method. Finally, the thermal displacement is obtained from the temperature field using a simplified estimation method. The results are validated by comparison with experimental data and with results from commercial finite element method software, demonstrating the effectiveness and real-time performance of the proposed approach. No potential conflict of interest relevant to this article was reported.

American Astronomical Society Acta Medica Okayama 0004-637X 999 2 2026 Constraining the Effects of Pre- and Post-accretionary Processes on Ryugu Insoluble Organic Matter 187 EN Christian Potiszil Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Masahiro Yamanaka Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Tsutomu Ota Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Chie Sakaguchi Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Hiroshi Kitagawa Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Ryoji Tanaka Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Tak Kunihiro Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Katsura Kobayashi Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Eizo Nakamura Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Asteroidal and cometary fragments have been indicated as possible sources of the building blocks of life for the early Earth. Samples returned from the asteroid Ryugu are uncontaminated and contain organic matter. Such samples enable an investigation of the processes that formed and altered extraterrestrial organic matter. Here, the FTIR and Raman responses of insoluble organic matter (IOM) isolated from Ryugu particles and carbonaceous chondrites are reported. Several relationships were observed: (1) a strong positive correlation of CH2/CH3 plotted against aliphatics/C=C; (2) a strong negative correlation of CH2/CH3 plotted against δ15N and δ13C; and (3) strong negative correlations of FTIR band ratios plotted against Raman band parameters and D/G values. The data are not consistent with even moderate heating of the IOM, as indicated by CH2/CH3 ratios that are consistent with unheated carbonaceous chondrites. The C and N isotope data previously collected for each Ryugu particle preclude aqueous alteration based on our understanding of its effects on carbonaceous chondrite IOM. Mixing of several IOM endmembers was considered, but due to the similarities of the particle with the lowest CH2/CH3 ratio to the other particles in terms of its other spectroscopic parameters, this scenario was considered unlikely. Finally, the effects of irradiation were considered, and UV irradiation, in particular, was hypothesised to be the best explanation for the trends observed. Overall, the data highlight the importance of comprehensive data sets for revealing extraterrestrial processes, which could define the nature of organic matter reaching habitable environments, such as those of the Early Earth. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0022-152X 63 8 2026 First Total Synthesis and Structural Elucidation of Microcystbiopterin C, a Pterin Glycoside From a Microcystis Bloom 1278 1287 EN Tadashi Hanaya Department of Chemistry, Faculty of Science, Okayama University Katsuya Iwasaki Department of Chemistry, Faculty of Science, Okayama University The first total synthesis and unambiguous structural elucidation of microcystbiopterin C, a pterin glycoside isolated from a Microcystis bloom, has been achieved. Two candidate biopterin glycosides (5a and 5b) corresponding to the proposed structures of microcystbiopterin C were synthesized by glycosylation of a suitably protected biopterin derivative 10 with 2,4-di-O-benzoyl-6-deoxy-3-O-methyl-α-L-mannopyranosyl bromide (9) and the corresponding α-D-mannopyranosyl bromide (22), respectively, followed by stepwise deprotection. Detailed comparison of the NMR data and the specific rotation of compounds 5a and 5b with those of the natural product established that microcystbiopterin C possesses the structure of 2′-O-(6-deoxy-3-O-methyl-α-D-mannopyranosyl)biopterin (5b). No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1086-9379 61 4 2026 The effects of pressure on immiscibility in metallic, core‐forming liquids: Implications for protoplanetary differentiation 720 738 EN Geoffrey David Bromiley School of GeoSciences, University of Edinburgh, Grant Institute Hidenori Terasaki Department of Earth Sciences, Okayama University Matthew Varnam School of GeoSciences, University of Edinburgh, Grant Institute Mechanisms for metal core formation in rocky planetesimals and planetary embryos remain poorly constrained, in part due to complexities arising from immiscibility in core-forming liquids at low pressures. To assess the pressure dependence of immiscibility and its role in protoplanetary differentiation, we performed experiments at 3 and 5 GPa in the system Fe0.9Ni0.1 + S, P, C. Immiscibility arises due to the highly non-ideal nature of light element mixing in Fe liquids, and results in separation of Fe-rich (S-depleted, C-rich, P-rich) and FeS-rich (S-rich, C-rich, P-depleted) liquids. For a broad range of core-forming liquid compositions, a miscibility gap is only present at pressures <5 GPa. With increasing pressure, the behavior of complex systems converges on that of the Fe-S-C ternary, although S-P-C interactions continue to influence metal liquid compositions and stability. Comparison with planetary core compositions derived from meteorite data suggests that immiscibility can play a significant role during melting in planetesimals, and up to medium-sized planetary embryos. In turn, the importance of immiscibility during differentiation depends on the extent of melting, mechanisms for core formation, and corollary degree of light element loss from planetary bodies. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0953-8194 38 9 2026 Marine flatworms as windows into the evolution of bilaterian neuropeptide signalling e70259 EN Ryo Nakamura Ushimado Marine Institute, Faculty of Science, Okayama University Mayuko Hamada Ushimado Marine Institute, Faculty of Science, Okayama University Xavier Bailly Multicellular Marine Models Team, CNRS – Sorbonne University – Station Biologique de Roscoff Hirotaka Sakamoto Department of Biology, Faculty of Environmental, Life, Natural Science and Technology, Okayama University Tatsuya Sakamoto Ushimado Marine Institute, Faculty of Science, Okayama University The evolutionary origin(s) of neuropeptide signalling is still largely unknown. It has been hypothesised that signal transmission via neuropeptides played a crucial role in the regulation of nervous systems in the bilaterian ancestor. Identification, expression and functional analyses of neuropeptides and their receptors across different taxonomic groups are important for better understanding the origin(s) of bilaterian neuropeptide signalling. An example is flatworms belonging to the Platyhelminthes (spiralian protostomes) and Xenacoelomorpha (sister to all Bilateria or sister to Ambulacraria). Despite their simple morphology (i.e., a body plan lacking a coelom and circulatory system), they often possess brain-like central nervous systems and a number of bilaterian-conserved neuropeptides. This feature makes them useful models for analyses of neuropeptides and their links to nervous systems. Although previous studies have revealed orthologous relationships between vertebrate neuropeptides and those found in both marine Platyhelminthes and Xenacoelomorpha, our work suggests possible ancestral functions of vasopressin/oxytocin (VP/OT) peptides (platytocin) in these groups. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2041-1723 17 1 2026 Water exchange process and bulk composition regulate slab dynamics and deep earthquakes 8291 EN Jintao Zhu Institute for Planetary Materials, Okayama University Renbiao Tao Center for High Pressure Science and Technology Advanced Research (HPSTAR) Lifei Zhang SKLab-DeepMinE, MOEKLab-OBCE, School of Earth and Space Sciences, Peking University Takayuki Ishii Institute for Planetary Materials, Okayama University Water strongly influences deep mantle processes, including geochemical cycles, slab dynamics, and deep-focus earthquakes. Yet the stability and interactions of hydrous minerals with nominally anhydrous minerals (NAMs) under the water-undersaturated conditions of subducting slabs remain unclear. Here we show, using high-pressure and high-temperature experiments on MgO–SiO2–H2O systems (~2 wt% H2O), that hydrous minerals progressively dehydrate in the mantle transition zone, transferring water to NAMs such as wadsleyite and ringwoodite, while the cold slab core stays nearly dry. Rapid dehydration near the top of the lower mantle may generate fluids linked to the deepest earthquakes. Our results indicate that dry olivine transformations, rather than dehydration embrittlement, likely trigger most deep-focus earthquakes, and that hydration variations in NAMs influence slab deformation and stagnation above 660 km. The bulk Mg/Si ratio controls hydrous mineral stability, suggesting harzburgite transports water more efficiently than peridotite. No potential conflict of interest relevant to this article was reported.

一般社団法人 電気学会 Acta Medica Okayama 0385-4221 146 9 2026 多様な電力消費形態を考慮したスマートグリッド運用の最適化 864 876 EN Takaki Kawamoto Faculty of Environmental, Life, Natural Science and Technology, Okayama University Yuriko Toda School of Creative Science and Engineering, Waseda University Takashi Hasuike School of Creative Science and Engineering, Waseda University 　This study examines an optimal operation model for a smart grid composed of multiple microgrids to promote renewable energy use in Japan. In Japan, about 70% of electricity is still supplied by fossil fuel power, while renewables account for only 18% despite a 36–38% target for 2030. Using demand and photovoltaic data from Setagaya Ward, we construct a system model with factory/office and residential microgrids and formulate a mathematical optimization model that considers power interchange, batteries and heat storage. Numerical experiments based on several case studies show the effectiveness of smart grid operation designed according to the proposed model in promoting renewable energy utilization and reducing total generation cost. In particular, the results show that increasing photovoltaic capacity, increasing the number of microgrids, and considering heat demand are all effective measures. However, these benefits depend on the season. Future work should extend the system model to account for seasonal variability and associated investment costs. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0005-2728 1867 4 2026 Cryo-EM structure of photosystem II D1-V185T mutant from Thermosynechococcus vestitus 149598 EN Haowei Jiang Research Institute for Interdisciplinary Science, Advanced Research Field and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yoshiki Nakajima Research Institute for Interdisciplinary Science, Advanced Research Field and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Fusamichi Akita Research Institute for Interdisciplinary Science, Advanced Research Field and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hongjie Li Center for Transformative Science, School of Life Science and Technology and Shanghai Clinical Research and Trial Center, ShanghaiTech University Koji Kato Research Institute for Interdisciplinary Science, Advanced Research Field and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Miwa Sugiura Proteo-Science Research Center, Ehime University Jian-Ren Shen Research Institute for Interdisciplinary Science, Advanced Research Field and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Photosystem II (PSII) catalyzes water oxidation into electrons, protons and dioxygen at its catalytic center, a Mn4CaO5 cluster, utilizing light energy. An amino acid residue D1-V185 in the D1 protein is located close to the Mn4CaO5 cluster, and plays a critical role in its catalytic function. In this research we purified PSII dimers from a D1-V185T mutant of Thermosynechococcus vestitus and analyzed its structure using low-damage cryo-electron microscopy (cryo-EM) at a resolution of 1.88 Å. The results revealed the presence of multi-conformations at the mutation site. Unlike the wild-type valine, which does not allow water molecules to be able to form hydrogen-bonds with it, both conformations of the mutant formed hydrogen bonds with nearby water molecules, which leads to rearrangement of the hydrogen bond networks in the O1 and Cl-1 channels. In conformation-A, the mutated Thr residue forms a hydrogen bond with a water molecule W6, which creates a new channel that bypasses the original O1 channel. Due to the hydrophilic OH group of Thr, the side-chain of D1-Glu189 was attracted and shifted toward the mutant Thr residue. In conformation-B, it forms a hydrogen bond with a water molecule W9 in the Cl-1 channel, bringing W9 closer and thereby disrupting the hydrogen bond network of the Cl-1 channel. In addition, multi-conformations of D2-K317, which is a ligand of Cl-1, were found in the mutant. These changes alter the environment surrounding the Cl-1 ion and Mn4CaO5, thereby affecting the PSII water-oxidation activity. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2643-6728 7 4 2026 Graphene Oxide: Designing a Functional Smarter Material for Advanced Biomedicine 399 409 EN Cécilia Ménard-Moyon CNRS, Immunology, Immunopathology and Therapeutic Chemistry, UPR3572, University of Strasbourg, ISIS Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Alberto Bianco Research Institute for Interdisciplinary Science, Okayama University Graphene oxide (GO) has emerged as one of the most extensively studied two-dimensional (2D) materials, thanks to its large surface area and abundance of functional groups, which enable applications across energy, catalysis, electronics, construction, and mobility. Its exceptional dispersibility in water further expands its use in the biomedical field. However, researchers have consistently expressed concerns about the limited control over GO chemical composition and structural heterogeneity. These factors are often overlooked, strongly affecting the reproducibility in both synthesis and applications. Because GO is considered a promising platform for advanced drug delivery, achieving reproducible preparation and precise structural control is essential to make it a reliable alternative to the many nanomaterials currently being explored for nanomedicine.<br> Motivated by these challenges, we have focused our work on identifying and controlling the key parameters that govern GO structure and surface chemistry. Over the past decade, we have developed methods to produce GO with controlled and tunable chemical structures, clarified the reactivity of its major functional groups, and developed robust strategies for postfunctionalizing GO with therapeutic agents, targeting ligands, and imaging dyes. In parallel, we have established systematic approaches to evaluate GO biocompatibility and biodegradability, revealing how specific physicochemical features influence biological responses and clearance pathways.<br> Together, these findings provide a unified framework linking GO synthesis, chemical modification, and biological behavior. By integrating chemical control, functional performance, and safety assessment, our work outlines a coherent strategy for the rational design of GO-based biomedical materials. We believe that this Account offers a solid foundation for the targeted exploitation of GO in nanomedicine and will help facilitate its eventual clinical translation. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0360-3199 270 2026 The effect of end-gas auto-ignition flame properties on the knocking intensity of a dual-fuel hydrogen engine 157103 EN Riku Okamoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nobuyuki Kawahara Faculty of Environmental, Life, Natural Science and Technology, Okayama University Yoshimitsu Kobashi Faculty of Environmental, Life, Natural Science and Technology, Okayama University This 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.

Elsevier BV Acta Medica Okayama 0360-3199 270 2026 Synergistic effects of gas-to-liquid pilot ignition and high rates of nitrogen-based simulated EGR on PREMIER combustion in dual-fuel hydrogen engines 157237 EN Nirendra Nath Mustafi Graduate School of Natural Science and Technology, Okayama University Nobuyuki Kawahara Graduate School of Natural Science and Technology, Okayama University Yoshimitsu Kobashi Graduate School of Natural Science and Technology, Okayama University Hydrogen-fueled compression-ignition engines offer a pathway to decarbonize heavy-duty propulsion but face a trade-off between thermal efficiency, NOx emissions, and narrow knock-free windows. Although EGR dilution and pilot-fuel reactivity control have each been studied independently, their combined effect on hydrogen PREMIER (PREmixed Mixture Ignition in the End-gas Region) combustion has not been systematically characterized. This study addresses that gap by comparing diesel and high-cetane Gas-to-Liquid (GTL) pilot fuels in a supercharged hydrogen dual-fuel engine, while varying nitrogen addition to isolate the inert dilution effect of simulated EGR (0–50%). GTL's superior ignitability shortened ignition delay and enhanced combustion stability versus diesel. Increasing inert EGR (nitrogen) dilution suppressed NOx by over 90% (360 to 30 ppm) via reduced peak temperatures, while sustaining knock-free PREMIER combustion and achieving a peak indicated thermal efficiency of 43.55% at ∼0.80 MPa IMEP. Coupling pilot-fuel reactivity control with EGR dilution enables safe, clean, high-efficiency hydrogen dual-fuel. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1616-301X 2026 Biomineral-Inspired Organic/Inorganic Colloidal Liquid-Crystalline Hybrids for Photoresponsive Adhesion e77420 EN Junya Uchida Research Institute for Interdisciplinary Science, Okayama University Ryuta Kiguchi Department of Chemistry and Biotechnology School of Engineering, The University of Tokyo Riki Kato Research Institute for Interdisciplinary Science, Okayama University Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Takashi Kato Research Institute for Interdisciplinary Science, Okayama University Bioinspired hybrid nanostructures offer a promising strategy for developing dynamic functional materials. Herein, we report a new class of photoresponsive liquid-crystalline (LC) adhesives based on organic/inorganic nanostructured colloidal hybrids. These LC materials are composed of a biomineral-inspired hydroxyapatite (HAp) nanorod and azobenzene-based forklike molecules. The organic/inorganic LC hybrids exhibit unusual photo-enhanced adhesion upon photoinduced order–disorder phase transitions of these LC materials. The photoresponsive adhesion functions of the colloidal LC hybrids are tuned by spacer moieties of the forklike molecules as well as mixing of the hybrids with the forklike molecules. The reversible photo-enhanced adhesion of the LC hybrids is achieved when the forklike molecule having oligooxyethylene spacers is hybridized with the HAp nanorod. The flexible oligooxyethylene spacers of the forklike molecule are effective for the formation of less ordered packing of the azobenzene units in the LC hybrids, which enables the dynamic photoresponsive functions. We propose an approach to the development of bioinspired photoresponsive LC materials through self-assembly of functional organic molecules and biomineral-based colloidal hybrids. No potential conflict of interest relevant to this article was reported.

Oxford University Press (OUP) Acta Medica Okayama 2328-8957 13 6 2026 Digital Tattoos in Infectious Diseases Management ofag338 EN Hideharu Hagiya Department of Infectious Diseases, Okayama University Hospital The widespread adoption of electronic medical records (EMRs) has improved continuity and efficiency in healthcare; however, the permanence of digital documentation may unknowingly and unintentionally disadvantage patients. Certain infectious disease–related labels, particularly those denoting colonization of antimicrobial-resistant organisms, status of stigmatized diseases, or antibiotic drug allergy, frequently persist long after their clinical relevance has expired. These Digital Tattoos silently influence clinical decision-making and impose multifaceted burdens, leading to unnecessary isolation, excessive use of broad-spectrum antimicrobials, psychological distress, higher healthcare costs, and reinforcement of stigma. A critical mismatch exists between static (unchanged) EMRs and the dynamic (changeable) nature of clinical conditions. To mitigate the harms of Digital Tattoos, we must urgently move beyond passive documentation toward proactive management of healthcare data. Decoupling the permanence of digital records from systemic inequities in patient care hinges on the robust synthesis of Digital Humility and patient-oriented risk evaluation. No potential conflict of interest relevant to this article was reported.

Optica Publishing Group Acta Medica Okayama 2026 Demonstration of a Raman Silicon Nanocavity Laser Emitting in the L-Band with S-band excitation FM4B.2 EN Rikuto Ichinose Department of Physics and Electronics, Osaka Metropolitan University Shoei Yamasaki Department of Physics and Electronics, Osaka Metropolitan University Ayumi Ishihara Department of Environmental, Life, and Natural Sciences, Okayama University Yuta Kanemaru Department of Physics and Electronics, Osaka Metropolitan University Takashi Asano Department of Electronic Science and Engineering, Kyoto University Susumu Noda Department of Electronic Science and Engineering, Kyoto University Yasushi Takahashi Department of Environmental, Life, and Natural Sciences, Okayama University We demonstrated a Raman silicon nanocavity laser that enables wavelength conversion from the S-band to the L-band. Compared with Raman lasers operating from the E-band to the C-band, a degradation in lasing threshold was observed. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1759-9954 17 29 2026 Effect of graphene oxide sheet size on pickering miniemulsion polymerization of styrene 3226 3236 EN Yue Zhang Cluster for Advanced Macromolecular Design, School of Chemical Engineering, The University of New South Wales Yasemin Fadil Cluster for Advanced Macromolecular Design, School of Chemical Engineering, The University of New South Wales Yuta Nishina Research Core for Interdisciplinary Sciences, Okayama University Vipul Agarwal Cluster for Advanced Macromolecular Design, School of Chemical Engineering, The University of New South Wales Per B. Zetterlund Cluster for Advanced Macromolecular Design, School of Chemical Engineering, The University of New South Wales The effect of graphene oxide (GO) sheet size on the progression of Pickering miniemulsion polymerization of styrene was systematically investigated using two GO samples with lateral dimensions (∼500 nm and 5–10 µm). Key parameters, including the presence of the conventional surfactant sodium dodecyl sulfate (SDS), GO loading, and initiator concentration, were investigated individually. Miniemulsion polymerization with GO was successfully conducted both in the absence and presence of SDS, with the addition of SDS leading to a significant rate enhancement attributed to SDS-induced secondary nucleation. In the presence of SDS, GO sheet size influenced polymerization behavior, and its effect on polymerization rate and monomer conversion exhibited opposite trends at different GO loadings. Small GO (∼500 nm) led to higher conversion and faster rates at high GO loading (5 wt%), whereas large GO (5–10 µm) resulted in higher conversion and faster rates at low GO loading (0.5 wt%). This size-dependent effect became more pronounced at lower initiator concentration. Overall, while GO sheet size exhibited a measurable influence on polymerization behavior, the overall kinetics were primarily governed by SDS-induced secondary nucleation. These findings provide new insights into the role of GO lateral dimensions in miniemulsion polymerization and offer guidance for the design and synthesis of polymer/graphene (oxide) nanocomposites with tunable properties. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2076-2615 16 15 2026 The Impact of Cold Storage and Seasonality on Raw Cow Milk Microbiota, Assessed by Conventional and Viability PCR 2302 EN Phong Dinh Tran Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takeshi Tsuruta Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Naoki Nishino Graduate School of Environmental, Life, Natural Science and Technology, Okayama University The microbiota of healthy Holstein cow’s milk was analyzed to evaluate the effects of immediate (freezing at the farm: on-site workflow) and delayed processing (freezing after cool transport: laboratory workflow) and to investigate seasonal changes in September, November, and January. Propidium monoazide (PMA) was also used to distinguish between viable and non-viable cells. Microbiota composition differed between the laboratory and the on-site workflow. After cool transport, the abundances of Lactobacillus and Turicibacter increased, while those of Streptococcus, Bradyrhizobium, and Acinetobacter decreased. Based on the β-diversity assessment, the difference between viable and non-viable cells was marginal compared with the difference between on-site and laboratory workflows. In the subsequent on-site workflow experiment, seasonal variation was clearly demonstrated. The relative abundances of Lactobacillus, Turicibacter, and Bacillus were high in September; Staphylococcus, Phenylobacterium, and Bradyrhizobium in November; and Phyllobacterium in January. The seasonal effect was greater than the PMA treatment effect. Despite the study’s limitations, such as a limited number of milk samples and data from only one farm with a single management system, our findings indicate that storage and transport at low temperatures could lead to inaccurate assessments, particularly of opportunistic environmental microbiota. Viability PCR could help improve our understanding of the factors involved but would not substantially alter the raw milk microbiota. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 1386-1425 359 2026 Discrimination of nanovesicles using two-color laser-induced fluorescence detection 127928 EN Shunsuke Asahi Department of Chemistry, Okayama University Takashi Kaneta Department of Chemistry, Okayama University A two-color fluorescence-detection system was developed to distinguish between two types of nanovesicles labeled with different fluorescent dyes. This system employs two lasers emitting at distinct wavelengths (488 and 635 nm). These lasers are reshaped into sheet-like beams and focused at separate positions within a square capillary. As vesicles flow through the capillary, they pass through the laser beams and emit fluorescence when excited by the corresponding wavelength. This technique allows for the counting of vesicles and identification of the specific fluorophores on the vesicles based on their emission positions. The system was validated using liposomes labeled with fluorophores excited by the 488 and 635 nm lasers. It was then applied to differentiate CD63-positive extracellular vesicles (EVs) from other types of EVs in a culture media consisting of HeLa and A549 cells. Additionally, the system was used to study the effect of the anticancer drug doxorubicin on EV secretion in these cancer cells. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2096-241X 10 2 2026 A Microcontroller-Integrated Multichannel Time Detector for Paper-Based Analytical Devices — Applications to Viscosity Measurements in Saliva Analysis and Protease-Activity Assays 527 535 EN Jianchao Ren Department of Chemistry, Okayama University Kaewta Danchana Department of Chemistry, Okayama University Takashi Kaneta Department of Chemistry, Okayama University We designed and developed a microcontroller-integrated multichannel time detection system that uses a microfluidic paper-based analytical device (µPAD) to measure liquid viscosity. This detection system is equipped with ten detectors to enhance the throughput of the measurements. The µPAD utilizes capillary action to determine viscosity based on the flow time of a liquid sample. A conductivity detection system begins counting the flow time when a sample is introduced and stops the count when the sample reaches the detection electrode. Sodium chloride (NaCl) was pre-deposited in the detection channel of the µPAD to enhance the conductivity of non-conductive samples, and Grade 1 CHR chromatography paper was selected as the optimal vehicle for substrates after comparing various channel widths, paper types, and channel lengths. The device demonstrated a linear correlation between flow time and viscosity for bovine serum albumin (BSA) and glucose solutions, which validates the theoretical model. The time readout measured protease activity when gelatin was used as a substrate and revealed an activity order of bromelain > papain > trypsin. The practical applicability of this system was further confirmed by testing real saliva samples, which demonstrated that the viscosity of saliva decreases rapidly after collection. Moreover, the results indicate that saliva viscosity was increased during extended durations of exercise. Overall, this µPAD system provides a simple, low-cost, and portable solution for viscosity measurement, with potential applications in clinical diagnostics and field measurements. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1356-9597 31 5 2026 Transforming Life Science Through Chromosome‐Level Genome Assemblies e70145 EN Tetsuo Kon Department of Neurosciences and Developmental Biology, University of Vienna Kosuke Kataoka Graduate School of Engineering, Tokyo University of Agriculture and Technology Yi‐Jyun Luo Biodiversity Research Center, Academia Sinica Johannes Nicolaus Wibisana Genomics and Regulatory Systems Unit, Okinawa Institute of Science and Technology Graduate University Kouhei Toga Laboratory of BioDX, PtBio Co‐Creation Research Center, Genome Editing Innovation Center, Hiroshima University Narumi Uno Laboratory of Bioengineering, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences Yuki Monden Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Mayuko Hamada Ushimado Marine Institute, Okayama University Advances in long-read sequencing and Hi–C scaffolding have made chromosome-level genome assembly increasingly accessible to individual laboratories, shifting genome research from large consortium-led projects toward investigator-driven studies across diverse taxa. This transition allows researchers to select organisms based on biological questions rather than the prior availability of genomic resources. In this review, we summarize the core experimental and computational steps for generating, evaluating, and annotating chromosome-level assemblies, and examine how they have advanced research in non-model organisms and genetically complex systems. Representative case studies illustrate four major contributions: resolving structural variation and lineage-specific genome architecture, linking genome organization to phenotypic innovation and plasticity, reconstructing deep chromosome evolution and macrosynteny, and distinguishing homologous and homoeologous chromosomes in polyploid genomes. These examples show that chromosome-level assemblies provide more than complete reference sequences. They establish a continuous genomic coordinate system through which genes, regulatory elements, transposable element insertions, sequence variants, and cellular states can be interpreted within broader chromosomal, population, and evolutionary contexts. We describe this integrative perspective as “glocal biology.” Future progress will require pangenomic, population-scale, and haplotype-resolved resources integrated with multi-omics and functional analyses. Collectively, chromosome-level genomics is reshaping life science by embedding molecular functions within chromosomal and evolutionary contexts. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2589-0042 29 6 2026 Posterior shift of Shh-Fgf signaling in axolotl limb regeneration drives sequential digit formation 116256 EN Saya Furukawa Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Sakiya Yamamoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haruki Nakayama Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Ayaka Ohashi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Akira Satoh Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Do conserved morphogen modules generate a given form only via a single spatiotemporal deployment, or can alternative deployments yield the same morphology? Axolotl limb regeneration provides a tractable test bed. SHH and FGF8, universally used in limb formation across vertebrates, also operate in axolotl, although the spatial domain of Fgf8 differs markedly from that in amniotes. A mutual Shh/Fgf feedback loop is likewise conserved. Here, we show that, in axolotl, the active domain of this loop shifts progressively posterior as digit formation proceeds. In step with this anterior-to-posterior displacement, digit-forming regions are sequentially induced posteriorly, explaining the axolotl’s reversed order relative to the amniote posterior-to-anterior sequence. These findings indicate that conserved molecular toolkits can overcome differences in spatial deployment to produce equivalent final limb architectures, demonstrating that there is not a single route to a target morphology. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2589-0042 29 8 2026 Brain circadian clock neurons drive fitness advantages in Drosophila 117125 EN Sae Aikawa Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Shoichiro Tamura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Makiko Mimura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Taishi Yoshii Graduate School of Environmental, Life, Natural Science and Technology, Okayama University The adaptive significance of circadian clocks is widely assumed due to their ubiquity; yet, direct empirical evidence remains scarce. Evaluating these benefits is often confounded by pleiotropic effects in conventional circadian null mutants. To address this, we selectively altered the circadian period exclusively within brain clock neurons in Drosophila melanogaster. Multi-generational competition assays revealed that flies with aberrant rhythms exhibit a significant fitness disadvantage under standard light-dark (LD 12:12) cycles. This disadvantage was abolished under constant light, confirming that the selection pressure is specifically mediated by the circadian clock. Furthermore, paternity assays conducted under LD 12:12 indicated that the timing of brain clock neurons influences male reproductive success, providing a potential mechanistic link between clock-controlled behavior and fitness. Intriguingly, we found that these fitness costs are highly photoperiod-dependent. Under short-day conditions (LD 8:16), the short-period strain (dbtS) maintained a significantly higher overall frequency than the long-period strain (dbtL). Our behavioral observations suggest that this difference may be associated with the quality of activity rhythms; specifically, dbtS lacked defined morning peaks and showed suppressed nocturnal activity, potentially narrowing its window for reproductive interactions compared to dbtL. These findings illustrate that the circadian system does not merely track a 24-h cycle but functions as a flexible feature that enables flies to cope with changing day lengths by aligning their mating behavior with the most favorable time of day. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2056-306X 12 1 2026 Knockout analysis of period and timeless and EGFP-based visualization of per-expressing clock cells in the cricket circadian clock 12 EN Kenji Tomioka Graduate School of Natural Science and Technology, Okayama University Shintaro Inoue Bio-Innovation Research Center, Tokushima University Taro Mito Bio-Innovation Research Center, Tokushima University Yoshiyuki Moriyama Department of Natural Sciences, Kawasaki Medical School Taishi Yoshii Graduate School of Environmental, Life, Natural Science and Technology, Okayama University In the present study, we generated crickets with knockout of either period (per) or timeless (tim) gene by CRISPR/Cas9-based genome editing. We also identified a naturally occurring per- mutant lacking a large coding region including PAS domains. To examine possible synergistic effects, a per- and timKO double mutant was generated by applying genome editing to the per- crickets. Under constant darkness (DD), timKO crickets exhibited a locomotor rhythm with a free-running period of 23.06 ± 0.20 h (mean ± SD), which was significantly shorter than that of the parental strain (23.78 ± 0.12 h). By contrast, perKO and per- crickets showed basically similar phenotype of locomotor rhythm: they exhibited an arrhythmic pattern during the first two to three weeks after transfer to DD but subsequently showed a complex rhythmic pattern with one or multiple components with significantly longer free-running periods (33.35 ± 10.72 h). In the per-;timKO double mutants, approximately 60% of individuals became arrhythmic, while the remaining 40% exhibited complex rhythms with extremely longer free-running periods (37.0 ± 9.17 h) under DD. These results suggest the existence of an underlying oscillatory mechanism that is responsible for regulating locomotor rhythms independently of the canonical per/tim feedback loop. Furthermore, we generated a reporter line on a per− background by knocking egfp into exon 1 of the per gene, allowing egfp expression to report per transcription. EGFP expression was detected in three distinct clusters of cells within the optic lobe: two located along the dorsal and ventral boundaries between the lamina and medulla neuropils, and one situated near the accessory medulla. These findings raise the possibility that these form part of the circadian clock network that governs circadian locomotor rhythms. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1939-5981 2026 Micro-segregation of Primary Si in ADC14 (Al–17Si–4Cu) Alloy Produced by Unidirectional Continuous Casting EN Shuhei Takeuchi Graduate School of Environment, Life, Natural Science and Technology, Okayama University Shota Nakagawa UACJ Corporation Yoshifumi Shinzato UACJ Corporation Tadashi Minoda UACJ Corporation Naotaka Ohtsuka UACJ Corporation Mitsuhiro Okayasu Department of Mechanical and Systems Engineering, Okayama University An 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 BV Acta Medica Okayama 0016-6480 384 2026 Alternative transcription of the mouse Gh gene identifies an immune-associated transcript with species-specific structural divergence 114996 EN Ai Fukushima Graduate School of Natural Science and Technology, Okayama University Yu Takeuchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hibiki Fukuchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Sakura Egoshi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hirotaka Sakamoto Graduate School of Natural Science and Technology, Okayama University Sayaka Aizawa Graduate School of Natural Science and Technology, Okayama University Sakae Takeuchi Graduate School of Natural Science and Technology, Okayama University Growth hormone (GH) in mice is primarily expressed in the anterior pituitary, although Gh expression has been reported in extrapituitary tissues, including immune organs. However, the structure of immune-associated Gh transcripts remains poorly characterized. To determine whether splenic Gh transcripts differ from pituitary Gh mRNA, 5′- and 3′-rapid amplification of cDNA ends (RACE) analyses were performed. While 3′ RACE showed a shared polyadenylation site, 5′ RACE identified a novel exon located approximately 2 kb upstream of the conventional exon 1, generating a transcript (spl-Gh mRNA) with a distinct first exon but shared downstream exons with pituitary Gh mRNA (pit-Gh mRNA). RT-PCR analysis revealed that spl-Gh mRNA is predominantly expressed in immune tissues such as spleen and bone marrow, and its distribution did not correlate with Pit-1 mRNA expression. Quantitative RT-PCR further demonstrated that spl-Gh mRNA was expressed at levels comparable to those of pit-Gh mRNA in the mouse spleen, indicating that spl-Gh is one of the major Gh transcript forms in this tissue. Sequence analysis indicated that spl-Gh mRNA is predicted to retain coding potential for a GH protein. Comparative genomic analyses further demonstrated that genomic features associated with the spl-Gh transcriptional unit are conserved only in a subset of closely related Mus species. In contrast, although a spl-Gh–related transcript was detected in rat spleen, no properly spliced mouse-like transcript was identified under the present experimental conditions. The detected transcript exhibited intron retention and an in-frame stop codon, suggesting that it is unlikely to produce a functional GH protein. These findings identify a distinct immune-associated Gh transcript generated through alternative transcription of the mouse Gh gene and suggest that immune-associated Gh transcriptional mechanisms have undergone species-specific divergence among rodents. Together, these findings reveal previously unrecognized complexity in Gh gene regulation and highlight species-specific differences in immune-associated Gh transcripts. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2227-9032 12 12 2024 Toloese Generates Nitric Oxide through Natural Radiation of Far Infrared Rays, Reducing Serum Glucose, Cholesterol, and Triglycerides 1227 EN Min-Ho Yeo Department of Clinical Laboratory Science, Catholic University of Pusan Young-Hyeon Lee Department of Clinical Laboratory Science, Catholic University of Pusan Mi-Jin Ryu Department of Clinical Laboratory Science, Catholic University of Pusan Yong-Hak Choi SayM Co., Ltd. Hye-Sook Kim Division of International Infectious Diseases Control, Faculty of Pharmaceutical Sciences, Okayama University Kyung-Soo Chang Department of Clinical Laboratory Science, Catholic University of Pusan Toloese, a bed composition, is formulated with a combination of minerals of various wavelengths by utilizing a specific ratio and particle size. A maturation mixing technique is used without additional compression processes, resulting in the natural formation of numerous fine pores in the bed structure. At 40 °C, far infrared radiation in the range of 5–20 μm is emitted with a 0.916 radiant ratio, and the measured emitted radiant energy is 3.69 × 102 W/m2·μm. This study aimed to investigate the influence of far infrared radiation emitted from a Toloese bed on endogenous nitric oxide production. Clinical trials were conducted with 20 healthy adults aged 20 years. Blood samples were collected before and after Toloese bed usage for 1 h daily for 3 weeks. Nitric oxide levels in the saliva and blood of men and women significant increased after they used the Toloese bed for 1 h. Additionally, sweating sharply increased in the upper and lower body regions after Toloese bed usage. No hematological changes or adverse effects were observed, but blood glucose, cholesterol, and triglycerides decreased after Toloese bed usage compared with those before Toloese bed usage. These findings demonstrated that far infrared radiation emitted by the Toloese bed induced endogenous nitric oxide production and contributed to significant reductions in blood glucose, cholesterol, and triglyceride levels. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1356-9597 30 3 2025 Polished Rice Regulates Maturation but Not Survival of Secondary Cells in Drosophila Male Accessory Gland e70025 EN Shinichi Otsune Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Mirai Matsuka Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Chisato Shirakashi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Xuanshuo Zhang Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hideki Nakagoshi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University In Drosophila males, the accessory gland is responsive to nutrient signal-dependent regulation of fertility/fecundity. The accessory gland is composed of two types of binucleated epithelial cells, about 1000 main cells and 60 secondary cells (SCs). The transcription factors Defective proventriculus (Dve), Abdominal-B, and Ecdysone receptors (EcRs) are strongly expressed in adult SCs. In response to nutrient conditions during development, coordinated action between Dve and ecdysone signaling determines the optimal number of SCs and regulates their maturation. A downstream effector of ecdysone signaling, Ftz-F1, is crucial in this process. Another downstream effector, Polished rice (Pri), is small peptides of 11 or 32 amino acids. Here we show that pri is required for maturation of SCs and for male fecundity, whereas it is not involved in determination of the number of SCs. We provide evidence that Pri acts downstream of Ftz-F1 to regulate maturation but not survival of SCs. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0001-8686 358 2026 Revisiting particle formation beyond classical nucleation: A unified classification framework for nonclassical pathways 104018 EN Yuya Iida Faculty of Environmental, Life, Natural Science and Technology, Okayama University Satoshi Watanabe Department of Chemical Science and Engineering, Kyoto University Particle 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.

Institute of Electrical and Electronics Engineers (IEEE) Acta Medica Okayama 2169-3536 14 2026 A Novel Approximate Solution Method for Euclidean Steiner Tree Problem Based on Genetic Algorithm 122947 122962 EN Liping Zhang Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tsuyoshi Migita Faculty of Environmental, Life, Natural Science and Technology, Okayama University Norikazu Takahashi Faculty of Environmental, Life, Natural Science and Technology, Okayama University A novel approximate solution method for the Euclidean Steiner tree problem is proposed and its performance is demonstrated through experiments using 195 benchmark problem instances from the OR-Library. Given a finite number of terminal points, the proposed method first generates non-terminal points around each terminal point and at the same location as the Steiner point for each triangle obtained by the Delaunay triangulation for all terminal points. It next runs a genetic algorithm to select a subset of the generated non-terminal points, aiming to minimize the total edge length of a minimum spanning tree for all the terminal points and the selected non-terminal points. It then optimizes the locations of the non-terminal points in the tree using Weiszfeld’s method, while preserving the topology. It finally refines the tree by adding new non-terminal points, adding and removing edges, and optimizing the locations of all non-terminal points. The experimental results show that, among 150 benchmark problem instances with known optimal solutions, the proposed method successfully constructs a Euclidean Steiner tree for 61 instances. For the remaining 89 instances, it produces an approximate solution whose total edge lengths is less than 100.7% of the optimal. The experimental results also show that the proposed method obtains approximate solutions efficiently: within 1.5 seconds for instances with up to 100 terminal points and within 61 seconds for instances with up to 1,000 terminal points. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2168-8184 18 8 2026 Incidence and Time to Onset of Pseudophakic Cystoid Macular Edema (Irvine-Gass Syndrome) After 1,325 Consecutive Cataract Surgeries Performed by a Single Surgeon Over Four Years e114802 EN Toshihiko Matsuo Ophthalmology, Graduate School of Interdisciplinary Science and Engineering in Health Systems Chie Nakago-Matsuo Orthodontics, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Objectives<br> Macular edema after cataract surgery is known as pseudophakic cystoid macular edema or Irvine-Gass syndrome. The aim of this study was to determine the incidence and time to onset of cystoid macular edema after uncomplicated cataract surgery.<br> Methods <br> A retrospective review was conducted of 1,325 consecutive cataract surgeries performed by a single surgeon at a single institution over four years, from January 2022 to December 2025.<br> Results<br> Among 1,325 eyes, one or more macular cysts were detected by optical coherence tomography in 27 eyes (2.0%) of 22 patients who complained of blurred vision or decreased visual acuity after having no symptoms immediately after surgery. The 22 patients (27 eyes: 12 right and 15 left) comprised 12 men and 10 women. Their ages at the time of surgery ranged from 57 to 82 years, with a median of 75.5 years. Of the 27 eyes that developed macular cysts, 13 eyes with no preoperative or intraoperative risk factors for inflammation received topical 0.1% bromfenac twice daily as the only postoperative anti-inflammatory treatment, together with topical antibacterial 0.5% moxifloxacin four times daily. In contrast, the remaining 14 eyes, which had risk factors for inflammation, such as exfoliation, floppy iris, poor mydriasis, extracapsular cataract extraction, or diabetes mellitus, received topical bromfenac twice daily and 0.1% betamethasone (or 0.1% fluorometholone in two eyes) four times daily, as well as topical moxifloxacin. The time from surgery to the diagnosis of macular cysts ranged from one week to eight months, with a median of two weeks, in the 13 eyes treated with topical bromfenac only. In the 14 eyes treated with the combination of topical bromfenac and betamethasone, the time to diagnosis ranged from two weeks to 13 months, with a median of two months. In 26 of the 27 eyes, the macular cysts disappeared and visual acuity returned to normal without residual symptoms within two weeks to seven months, with a median of one month, after topical betamethasone four times daily was initiated or resumed.<br> Conclusions <br> Pseudophakic macular cysts developed during the postoperative course in eyes with no preoperative or intraoperative risk factors that received topical bromfenac alone. They also developed later in the postoperative course after the combination of topical bromfenac and betamethasone was discontinued in eyes with risk factors for inflammation. The macular cysts disappeared following the initiation or resumption of topical betamethasone, accompanied by recovery of visual acuity and resolution of symptoms. No potential conflict of interest relevant to this article was reported.

Institute of Electrical and Electronics Engineers (IEEE) Acta Medica Okayama 0885-8993 41 11 2026 Structural Design of Litz Wires for Reducing AC Transport Current Loss Using an Equivalent Circuit Model Considering the Path of All Strands 19516 19529 EN Ryota Inoue Graduate School of Environment, Life, Natural Science, and Technology, Okayama University Hiroshi Ueda Graduate School of Environment, Life, Natural Science, and Technology, Okayama University SeokBeom Kim Graduate School of Environment, Life, Natural Science, and Technology, Okayama University Litz wires are generally fabricated based on the proprietary know-how of wire manufacturers. Therefore, the design guidelines for the conductor structure of low-loss Litz wires have not been clearly established. In this study, we investigated the effect of differences in the conductor structure on the AC resistance using the equivalent circuit model considering the path of all strands. Moreover, we proposed design guidelines for the conductor structure of Litz wires to reduce AC resistance originating from strand paths. Furthermore, we prototyped Litz wires according to the proposed design guidelines and compared the AC resistance of the proposed Litz wires with that of commercial Litz wires. As a result, the AC resistance of the prototyped Litz wires according to the proposed design guidelines was reduced compared to that of the commercial Litz wires. Moreover, the quality factor of the spiral coil using the proposed Litz wire was higher than that using the commercial Litz wire. From the above results, we experimentally clarified that the proposed design guidelines for the conductor structure of Litz wires are effective in reducing the AC resistance originating from strand paths. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2662-9984 7 1 2026 Diversity of hymenopteran assemblages prevailed during reproductive stage of cotton—implications for natural control 1039 EN Md Mizanur Rahman Insect Biotechnology and Biopesticide Laboratory, Department of Entomology, Bangladesh Agricultural University Tohru Hayakawa Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mohammad Tofazzal Hossain Howlader Insect Biotechnology and Biopesticide Laboratory, Department of Entomology, Bangladesh Agricultural University Hymenoptera is one of the most important insect orders contributes to pollination, biocontrol and natural control largely unexplored from Bangladesh. We, therefore, assess the diversity and relative abundance of hymenopteran insects in cotton fields from five locations of Bangladesh using five types of traps (Malaise, Yellow Pan, Fluorescent Yellow Pan, Pitfall, and Sweep Net). Analysis of samples revealed presence of diverse type of hymenopteran insects from the studied locations, with a total of 1642 insects collected, representing 28 morphospecies and 16 families of the Hymenoptera. Formicidae, Braconidae, Diapridae, Figitidae, Ichneumonidae, Scelionidae constitutes the major families comprises of 36.37, 25.09, 5.36, 5.24, 5.18 and 4.93% of the populations respectively. Among the locations, cotton fields of Rangpur showed the highest species richness, diversity indices (Simpson, and Shannon values), while cotton fields located at Jashore had the lowest. Yellow and fluorescent pan traps captured insects from nearly all families, indicating broad sampling effectiveness. Malaise traps also sampled a wide range of families except for low captures of Formicidae. Pitfall traps primarily targeted Formicidae, consistent with their ground-dwelling hymenopterans. Sweep nets captured fewer families, reflecting a more selective sampling role. Among functional guilds, parasitoids were the most abundant, followed by predators, pollinators, and herbivores of hymenopteran insects. Overall, the hymenopteran community in cotton agroecosystems from Bangladesh was dominated by parasitoid families, indicating strong potential for natural biological control. Leveraging this natural enemy dominance could significantly reduce dependence on chemical insecticides. These findings support the integration of parasitoid conservation strategies into national Integrated Pest Management (IPM) programs and landscape-level pest management policies. No potential conflict of interest relevant to this article was reported.

American Society for Horticultural Science Acta Medica Okayama 0018-5345 61 9 2026 Stomatal Traits in Strawberry Cultivars: Variation among Plant Parts and Associations with Growth and Yield 1988 1991 EN Minori Hikawa-Endo Okayama University, Graduate School of Environmental, Life, Natural Science and Technology Ryosuke Yamanaka Western Region Agricultural Research Center, NARO Takayoshi Yano Western Region Agricultural Research Center, NARO Stomatal traits are important determinants of photosynthesis and water use; however, their variation among plant parts and cultivars and their relationships with growth and yield in strawberry remain unclear. This study characterized stomatal density and guard cell length among plant parts and across 34 cultivars and examined their associations with growth and yield. Stomata were found not only on the abaxial leaf surface but also on petioles and calyces and occasionally on the adaxial surface of leaves. Both traits varied widely among cultivars and decreased between November and May. Stomatal density was significantly negatively correlated with plant height, estimated leaf area, and total yield in both seasons, whereas guard cell length showed no significant association with these traits. These results suggest that stomatal density may be a more relevant indicator of growth and yield in strawberries and that characterizing stomatal traits across plant parts and cultivars may support breeding and cultivation research. No potential conflict of interest relevant to this article was reported.

Japanese Society for Lymphoreticular Tissue Research Acta Medica Okayama 1346-4280 66 2 2026 RHOA G17V mutation analysis redirecting diagnosis: nodal T-follicular helper cell lymphoma with classic Hodgkin lymphoma feature 122 129 EN Rio Yamada Department of Molecular Hematopathology, Okayama University Graduate School of Health Sciences Midori Filiz Nishimura Department of Molecular Hematopathology, Okayama University Graduate School of Health Sciences Asami Nishikori Department of Molecular Hematopathology, Okayama University Graduate School of Health Sciences Takuya Fukumi Department of Hematology, Okayama City Hospital Kumiko Ohsawa Department of Pathology, Saitama Medical Center, Saitama Medical University Shuji Momose Department of Pathology, Saitama Medical Center, Saitama Medical University Yasuharu Sato Department of Molecular Hematopathology, Okayama University Graduate School of Health Sciences Nodal T-follicular helper cell lymphoma (nTFHL) may present with Hodgkin/Reed–Sternberg (HRS)-like cells and can morphologically mimic classic Hodgkin lymphoma (CHL), although these entities are usually distinguishable. We report an unusual case showing marked morphologic and molecular overlap with CHL, creating a diagnostic challenge but ultimately considered biologically consistent with nTFHL.<br> An 81-year-old woman presented with stage IV disease involving the bone marrow and markedly elevated serum soluble interleukin-2 receptor levels. Excisional lymph node biopsy revealed scattered HRS cells in a T-cell–rich background, with strong CD30 and PD-L1 expression and weak PAX5 positivity, findings consistent with CHL. Fluorescence in situ hybridization demonstrated copy-number alterations at the 9p24.1 locus in HRS cells, further supporting molecular features characteristic of CHL.<br> However, the presence of two T-follicular helper markers, detection of the RHOA p.Gly17Val (G17V) mutation, and oligoclonal T-cell receptor rearrangements with shared peaks in lymph node and bone marrow indicated an underlying nTFHL. The differential therapeutic response also supported a diagnosis of nTFHL, which could not have been established on morphology alone.<br> In this case, although the HRS cells displayed morphological, immunophenotypic, and molecular features highly suggestive of CHL, the biological nature of the lesion was consistent with nTFHL. Compared with previously reported cases of nTFHL with HRS-like cells, this case more closely resembled CHL and may represent a distinct subset best described as “nTFHL with CHL features,” a concept warranting greater recognition among pathologists and clinicians. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2168-8184 17 3 2025 Cholecystectomy Is Linked to Worse Clinical Outcomes in Primary Sclerosing Cholangitis e80184 EN Nozomi Miyake Department of Gastroenterology and Hepatology, Okayama University Kengo Yasugi Department of Gastroenterology and Hepatology, Okayama University Akinobu Takaki Department of Gastroenterology and Hepatology, Okayama University Kazuyuki Matsumoto Department of Gastroenterology and Hepatology, Okayama University Hospital Motoyuki Otsuka Department of Gastroenterology and Hepatology, Okayama University Recent findings have suggested that gallbladder-derived retinoic acid signaling plays a crucial role in the regeneration of damaged intrahepatic biliary ducts. This retrospective cohort study analyzed the clinical records of 20 patients with primary sclerosing cholangitis (PSC) treated at our hospital between 2013 and 2024. We investigated the clinical implications of gallbladder removal in patients with PSC, a progressive cholangiopathy with limited therapeutic options. We retrospectively analyzed the data of patients with PSC and compared patients with and without prior cholecystectomy to assess the impact on disease progression using the Mayo risk score, Fibrosis-4 (FIB4) index, and other clinical parameters. Our findings indicated that cholecystectomy was associated with worse Mayo risk scores (p = 0.0004) and an elevated FIB4 index (p = 0.021), suggesting a potential link between gallbladder removal and accelerated disease progression. Furthermore, mortality and transplant-free survival analysis revealed significantly worse outcomes in the cholecystectomy group (odds ratio = 21.0, p = 0.032). However, given the retrospective nature and small sample size of this study, selection bias cannot be excluded, and further research is needed to confirm these findings. These findings support the hypothesis that gallbladder-derived factors, such as retinoic acid, may influence PSC progression and highlight the need for further research into therapeutic interventions targeting this pathway. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1523-7060 2026 Cathodic AziridinationUsing Dichloramine-Tas a Nitrogen Source EN Eisuke Sato Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kanon Nagamine Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Koichi Mitsudo Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Seiji Suga Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Aziridines are valuable motifs in organic synthesis due to their biological activities and their utility as synthetic intermediates. Although electrochemical methods have been developed for aziridine synthesis, these approaches rely on anodic oxidation. This study reports the first cathodic reduction-promoted aziridine formation using dichloramine-T as a nitrogen source. The reaction conditions were optimized via Gaussian process regression. Overall, this strategy enables aziridine formation with broad substrate scope, providing a practical platform that expands the electrochemical synthesis toolbox. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2168-8184 16 9 2024 Decreased CD3+CD56+ Natural Killer T Lymphocytes and Increased Human Leukocyte Antigen-DR+ Cells in the Inflamed Area of Pouchitis in Ulcerative Colitis Patients e70066 EN Masaya Iwamuro Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Takehiro Tanaka Department of Pathology, Okayama University Hospital Masahiro Takahara Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Toshihiro Inokuchi Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Sakiko Hiraoka Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Background: Pouchitis is an inflammatory condition that affects the ileal pouch during ileal pouch-anal anastomosis surgery. Despite its clinical significance, precise immunological mechanisms underlying pouchitis remain unclear. This study aimed to investigate the lymphocyte profile in the ileal pouch of patients with pouchitis compared to those with familial adenomatous polyposis (FAP) and ulcerative colitis without pouchitis using flow cytometry and immunohistochemical techniques.<br> Methods: We prospectively analyzed endoscopic biopsy specimens from the ileal pouches of 15 patients and categorized them into three groups: FAP, ulcerative colitis with an inflammation-free pouch (UC-I), and ulcerative colitis with ulcers and/or erosions in the pouch (UC-UE). Flow cytometry was used to assess various T-lymphocyte markers, including cluster of differentiation (CD) 4, CD8, CD56, and human leukocyte antigen (HLA)-DR. Immunohistochemistry was performed to visualize the spatial distribution of CD3+, CD56+, and HLA-DR+ cells in the pouch mucosa.<br> Results: We observed significantly reduced CD56+/CD3+ and CD8+/CD3+ ratios in the UC-UE group compared to those in the FAP group, indicating a disruption in natural killer T-cell populations. Immunohistochemical analysis revealed that the spatial distribution of lymphocytes differed among the non-inflamed mucosa, dense lymphocyte infiltration, and lymphoid follicles, with these components frequently intermingling. CD56 + cells were less abundant in areas with dense lymphocyte infiltration, whereas HLA-DR+ cells were more abundant.<br> Conclusion: Our study revealed a decrease in CD56+ natural killer T cells and an increase in HLA-DR+-activated T cells in areas with dense lymphocyte infiltration, suggesting an association between these cells and pouchitis in ulcerative colitis. The distinct patterns observed in non-inflamed mucosa, areas with dense lymphocyte infiltration, and lymphoid follicles underscore the need for further analyses of these three segments to elucidate the immunological mechanisms underlying pouchitis. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 2367-0932 10 7 2026 Photochemical Oxidative Esterification of Aldehydes with Radical-Sensitive Alcohols via CH Bromination e70221 EN Nova Alfian Hariyanto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haru Ando Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Atsuya Miyamoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hiroyoshi Takamura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Isao Kadota Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kenta Tanaka Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Photochemical esterification is an attractive strategy for the synthesis of multifunctionalized esters, and the use of aldehydes as substrates offers an alternative to conventional carboxylic acid–based approaches. In particular, reactions via acyl halide intermediates are useful for accessing functionalized esters; however, examples of such transformations remain limited so far, and their compatibility with radical-sensitive alcohols remains relatively unexplored. Here, we report a photochemical oxidative esterification of aldehydes with radical-sensitive alcohols enabled by CH bromination. This reaction proceeds without stoichiometric additives, such as bases, and enables the incorporation of a broad range of radical-sensitive functional groups into esters. Thus, it represents a promising platform for the synthesis of pharmaceuticals and functional materials. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0947-6539 2026 Synthesis of Tris(indol-3-yl)methanes From Indoles, CO2, and Dimethylphenylsilane With BPh3: Two-Step Construction of π-Conjugated Systems e71464 EN Sha Li Graduate School of Environmental, Life, Natural Science and Technology, Okayama University So Saibara Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Reito Yasui Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kazuto Takaishi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Natsumi Nitta Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tadashi Ema Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tris(indol-3-yl)methanes were synthesized from indoles, CO2, and PhMe2SiH in the presence of BPh3 in acetonitrile at 50°C. This is the first CO2 fixation reaction forming the aliphatic methine (>CH─) group. The isotope-labeling experiments clearly demonstrated that the carbon and hydrogen atoms of the methine group originated from carbon dioxide and dimethylphenylsilane, respectively. The mechanism for the multicomponent cascade reaction was elucidated by DFT calculations. One of the CO2-derived products, tris(4-bromo-1-methylindol-3-yl)methane, underwent palladium-catalyzed intramolecular cascade reactions for the selective formation of two novel polycyclic heteroaromatic compounds, where the methine C(sp3) atom originating from CO2 was converted into aromatic C(sp2) atoms. One is formally produced via double direct C─H arylation, Wacker-type oxidation, dehydrogenation, and debromination, while the other seems to be produced via the intramolecular homocoupling of aryl bromide, direct C─H arylation, Wacker-type oxidation, and dehydrogenation. Both of them are new intramolecular cascade reactions that are useful for the short-step construction of nitrogen-doped nanographenes. On the other hand, one of the CO2-derived products, tris(1-pentylindol-3-yl)methane, was converted into tris(1-pentylindol-3-yl)methylium methanesulfonate, which is a potential antitumor drug. This is the first derivatization of CO2 to a cationic C(sp2) center. No potential conflict of interest relevant to this article was reported.

Institute of Electrical and Electronics Engineers (IEEE) Acta Medica Okayama 2187-0136 15 7 2026 Ultra-Low Input Power Drivable IoT Wireless Sensor using Energy Harvesting from 2.45 GHz Wi-Fi 286 289 EN Masato Wadahama Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kazuhiro Fujimori Graduate School of Environmental, Life, Natural Science and Technology, Okayama University This letter implements an ultra-low-power IoT wireless sensor driven by energy harvesting (EH) from 2.45 GHz Wi-Fi and verifies its performance. First, a planar Yagi-Uda antenna was used to extend transmission distance, and its maximum gain was 12.2 dBi. Next, a high-conversion-efficiency rectifier was implemented using surface-mount components to achieve ultra-low input power operation and achieved 15.7% conversion efficiency at −20 dBm input power. Finally, connecting these components to the sensor module enabled sensor operation at a distance of 3.0 m from the Wi-Fi router. This shows that the proposed IoT wireless sensor offers high flexibility and enables semi-permanent operation. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0170-0839 83 10 2026 Osmotic pressure, correlation lengths and viscosity of aqueous pullulan solutions beyond the overlap concentration 565 EN Lingzi Meng Department of Materials Science and Engineering, The Pennsylvania State University Rene Iwato Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Takaichi Watanabe Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Carlos G. Lopez Department of Materials Science and Engineering, The Pennsylvania State University We investigate the thermodynamic, scattering, and flow properties of pullulan, a flexible non-ionic polysaccharide in aqueous solution, focusing on semidilute and concentrated solutions. We review dilute solution data for the intrinsic viscosity and radius of gyration and hydrodynamic radius of aqueous pullulan and find the Kuhn length and thermal blob size, below which the polymer chain is nearly ideal, to be 3 nm and 20 nm, respectively. We establish the scaling laws for static correlation length, specific viscosity, osmotic pressure, and osmotic compressibility across dilute, semidilute, and concentrated regions, finding that the scaling exponents align well with theoretical predictions but the crossover concentrations obtained from different methods are not consistent. The ratio between the osmotic and Ornstein–Zernike correlation lengths ξΠ/ξOZ is approximately 2.5 for aqueous solutions, similar to that observed in polystyrene in a theta solvent. This similarity may arise because the crossover concentration between the semidilute and concentrated regions c∗∗ is close to the overlap concentration c∗. No potential conflict of interest relevant to this article was reported.

American Society for Horticultural Science Acta Medica Okayama 1063-0198 36 5 2026 Effects of Transplanting Date and Photoperiod on Flowering of Everbearing Strawberries 789 797 EN Minori Hikawa-Endo Okayama University, Graduate School of Environmental, Life, Natural Science and Technology Ryosuke Yamanaka Western Region Agricultural Research Center, NARO Takayoshi Yano Western Region Agricultural Research Center, NARO Everbearing strawberries have the potential to produce fruit year-round if transplanted early. However, temperature and plant physiological status limit the continuous flowering. Herein, we aimed to investigate whether promoting flowering through long-day phototreatment enables earlier transplanting. The interaction between transplanting date and photoperiod in two everbearing strawberry cultivars was examined. In the 04 cultivar, which exhibited strong everbearing characteristics, rapid and continuous flowering occurred largely independent of long-day treatment, and early transplanting alone increased inflorescence number and early yield. However, excessive flowering was associated with reduced average fruit weight, soluble solid concentration, and firmness. Conversely, in Yotsuboshi, a cultivar with weak everbearing characteristics, earlier transplanting combined with extended photoperiods advanced the emergence of the first and second inflorescences. However, gains in total early yield were small, and the average fruit weight decreased compared with that in the control, indicating physiological stress. Across the cultivars, earlier inflorescence emergence was negatively correlated with days to flowering and positively associated with cumulative yield. For practical applications, cultivars with strong everbearing characteristics can be managed with early transplanting and minimal long-day supplementation to ensure early production. In contrast, cultivars with weak everbearing characteristics require extended photoperiods following early transplanting along with stress-mitigation strategies to maintain fruit size and quality. No potential conflict of interest relevant to this article was reported.

American Society for Horticultural Science Acta Medica Okayama 0018-5345 61 8 2024 Shoot-to-Root Ratio Serves as an Early Practical Indicator of Tipburn Risk in Lisianthus [Eustoma grandiflorum (Raf.) Shinn.] Seedlings 1884 1891 EN Nethone Samba Faculty of Food and Agricultural Sciences, Fukushima University Kureha Iki Fukushima Prefectural Iwaki Agriculture and Forestry Office Tanjuro Goto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Minori Hikawa-Endo Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Ken-ichiro Yasuba Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yoko Miyama Faculty of Food and Agricultural Sciences, Fukushima University, Fukushima, 960-1296, Japan; and The United Graduate School of Agricultural Sciences, Iwate University Tipburn is a calcium-related physiological disorder that reduces lisianthus seedling quality, yet the factors underlying cultivar differences remain unclear. This study evaluated 10 lisianthus cultivars to determine whether the shoot-to-root (S/R) ratio and key physiological traits influence tipburn susceptibility. Seedlings were grown in a closed production system with restricted root volume and once-daily irrigation to enhance symptom expression. The S/R ratio varied significantly among cultivars (2.82–4.02) and was strongly correlated with tipburn incidence (r = 0.744, P < 0.05) and severity (r = 0.706, P < 0.05). Cultivars with higher S/R ratios exhibited greater tipburn, whereas those with lower ratios showed little to no symptoms. Diurnal measurements of transpiration, stomatal conductance, leaf temperature, and electron transport rate revealed cultivar-specific physiological patterns; however, midday transpiration showed only a weak association with tipburn. These results indicate that biomass allocation, rather than physiological activity alone, is the primary factor governing tipburn susceptibility. The S/R ratio represents a simple and practical indicator for identifying high-risk cultivars in nursery production. Future studies should investigate the roles of calcium transport, developmental stage, and irrigation management in mitigating tipburn occurrence. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1463-9262 28 29 2026 Terpolymerization of epoxide, oxetane, and CO2 for the synthesis of polycarbonates with high CO2 contents, physical tunability, and enzymatic degradability 12214 12224 EN Kaito Niki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Chihiro Maeda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tadashi Ema Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Although poly(cyclohexene carbonate) (PCHC) synthesized by the copolymerization of cyclohexene oxide (CHO) and CO2 is a promising material, the physical properties of this material need to be altered and tuned for its wider applications. To this end, we employed a terpolymerization strategy increasing the CO2 content in the resulting polymers. Terpolymerization of CHO, oxetane, and CO2 using AlIII porphyrin catalysts with quaternary ammonium halides afforded polycarbonates with high CO2 contents, physical tunability, and enzymatic degradability. The counter anions of the catalysts were crucial factors in the formation of the poly(trimethylene carbonate) (PTMC) unit. 1a with bromide ions preferentially produced trimethylene carbonate (TMC) over PTMC, while 1d with chloride ions suppressed the formation of TMC and produced PCHC–PTMC directly. PCHC–PTMC showed glass transition temperatures (Tg) between 69 °C and −9 °C, depending on the PCHC/PTMC ratio. The tensile test revealed that the PTMC unit contributed to the softening of the film materials. For example, a film material with a CO2 content of 38 wt% showed 505% elongation at break with an elastic character, which contrasted starkly with the 1.3% elongation at break of PCHC with a CO2 content of 31 wt%. Moreover, the selective degradation of the PTMC unit in PCHC–PTMC was achieved with lipases, and a gradient character in the sequence structure was suggested. Overall, PCHC–PTMC is an environmentally benign and sustainable CO2-based polycarbonate. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0721-832X 2026 Dissociation between globe shape-induced rectus muscle pulley displacement and abduction limitation in patients aged 40 years and older with high myopic strabismus EN Reika Kono Department of Ophthalmology, Okayama University Graduate School of Medicine Dentistry, and Pharmaceutical Sciences Ichiro Hamasaki Lino Eye Clinic Fumiko Kishimoto Division of Ophthalmology, Ibara City Hospital Kiyo Shibata Lino Eye Clinic Shin Morisawa Department of Ophthalmology, Okayama University Graduate School of Medicine Dentistry, and Pharmaceutical Sciences Yuki Morizane Department of Ophthalmology, Okayama University Graduate School of Medicine Dentistry, and Pharmaceutical Sciences Purpose We hypothesized that high myopia (HM)-induced globe deformation displaces rectus muscle (RM) pulleys, contributing to mild ocular motility restriction. This study investigated the effects of globe shape on RM pulley positions in older Japanese patients with acquired strabismus (AS) and mild motility restriction—defined as the ability to abduct both eyes beyond the midline.<br> Methods In this retrospective case series, 28 patients (mean age ± standard deviation: 61.2 ± 9.0 years) with adult-onset AS were included: 6 patients with (LAB group) and 22 patients without abduction limitation (NLAB group). In each subject, the eye with the longer axial length (AL ≥ 26 mm), measured using an AL measurement apparatus, was analyzed using magnetic resonance imaging (MRI). RM pulley positions relative to the globe center and equatorial diameter (ED) were measured; the ED-to-AL ratio (EAR) was calculated. We compared these parameters between groups and analyzed correlations of globe-shape factors (EAR, AL, and ED) with pulley positions and age.<br> Results No significant differences in EAR, AL, ED, or pulley positions were detected between LAB and NLAB groups, possibly owing to the limited sample size and group imbalance, in the analyzed eyes. However, as EAR decreased (prolate deformation), the superior rectus (SR) pulley (r = 0.68, P < 0.01) and inferior rectus (IR) pulley (r = 0.40, P = 0.03) significantly displaced nasally. AL (r = -0.52, P < 0.01) correlated with the horizontal SR pulley position. Furthermore, age significantly correlated with AL (r = 0.45, P = 0.02) and decrease in EAR (r = -0.41, P = 0.03).<br> Conclusions In older Japanese patients with HM and AS, prolate globe deformation was associated with age and significantly correlated with SR and IR pulley positions. While the direct relationship between these structural changes and the clinical degree of mild abduction limitation requires further investigation in larger cohorts, EAR sensitively reflected age-related morphological shifts; thus, when used in conjunction with AL, EAR may represent a readily measurable MRI-based parameter associated with restrictive motility tendencies in strabismus with high myopia. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0016-2361 429 2027 Mechanism of Enhanced Heat Release in Spray Combustion of a Methanol–DME Blended Fuel 140693 EN Yoshimitsu Kobashi Faculty of Environmental, Life, Natural Science and Technology, Okayama University Shodai Makino Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Masakuni Namba Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nobuyuki Kawahara Faculty of Environmental, Life, Natural Science and Technology, Okayama University Katsuyoshi Asaka Technical Management Division, Carbon Neutral Technology Department, DAIHATSU INFINEARTH MFG. CO., LTD. Kazuyuki Kobayashi Technical 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.

Ceramic Society of Japan Acta Medica Okayama 1348-6535 134 7 2026 Dielectric response modulation in relaxor (Sr,Ba)Nb2O6 via engineered defect 455 460 EN Ryusei Shiota Graduate School of Natural Science and Technology, Okayama University Takashi Teranishi Graduate School of Natural Science and Technology, Okayama University Shinya Kondo Department of Energy Engineering, Nagoya University Akira Kishimoto Graduate School of Natural Science and Technology, Okayama University Defect engineering provides an effective pathway to tune the dielectric response of relaxor ferroelectrics, yet the roles of individual defect species in tungsten bronze (TTB) systems remain unclear. Here, we investigated how engineered Ti–VO•• defect dipoles and native oxygen vacancies introduced through reduction annealing modify the dielectric properties of relaxor (Sr0.5,Ba0.5)Nb2O6 (0.5-SBN). Ti loading forms stable defect dipoles that generate smaller polar nanoregions (PNRs), suppress their overgrowth, and increase the number of dynamically active PNRs at room temperature, leading to enhanced permittivity ε′ while preserving DC-bias stability and breakdown strength (EB). Reduction annealing generates Nb4+-related local polarizations aligned with the external electric field, which strengthen dipole fluctuations and slightly increase ε′. Electron localization further relaxes the TTB-A2 site disorder–induced random fields, yielding a sharper dielectric peak and promoting more uniform PNR growth. Microwave dielectric spectroscopy combined with electromagnetic simulations revealed that the increases in ε′ for both Ti-loaded and reduced samples (0.5-SBNT and Reduced 0.5-SBN, respectively) originate predominantly from enhanced dipole polarization. Despite grain coarsening in 0.5-SBNT, the EB remained unchanged, indicating that defect dipoles act as pinning centers that inhibit field-induced PNR aggregation. In reduced 0.5-SBN, EB increased up to pO0 = 4.3 × 10−3 atm owing to relaxed random fields, whereas excessive reduction reduced EB through carrier-driven space-charge effects. These results demonstrate that precise control of defect species enables simultaneous optimization of ε′, DC-bias stability, and EB in TTB-type relaxor ferroelectrics. No potential conflict of interest relevant to this article was reported.

Frontiers Media SA Acta Medica Okayama 1664-462X 17 2026 Quantitative resistance to Rhizoctonia solani AG-4 develops independently in leaves and roots of Brachypodium distachyon 1875734 EN Rozi Fernanda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Niranjan Mahadevan Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Natsuka Kohno School of Agriculture, Okayama University Reiko Nagao School of Agriculture, Okayama University Megumi Watanabe Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nanami Sakata Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hidenori Matsui Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kazuhiro Toyoda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuki Ichinose Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yusuke Kouzai Crop Stress Management Group, Division of Plant Molecular Regulation Research, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO) Keiichi Mochida RIKEN Center for Sustainable Resource Science Yoshiteru Noutoshi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Rhizoctonia solani is a soil-borne phytopathogen with a broad host range, classified into multiple anastomosis groups (AGs). While the rice sheath blight pathogen AG-1 IA is well-studied, defense mechanisms against AG-4, which infects diverse monocots and dicots, remain unclear. Here, we screened 153 Brachypodium distachyon accessions for resistance to AG-4 HG-I+II using both leaf and soil inoculation assays. The accessions exhibited a quantitative resistance spectrum in both assays. Some accessions were resistant to both methods, while others showed resistance in only one, indicating that leaf and root defenses operate independently. Unlike the salicylic acid (SA)-dependent resistance observed in several accessions against AG-1 IA, AG-4 leaf resistance appears to be largely SA-independent. Among 22 resistant accessions, only eight induced the SA marker BdWRKY38, whereas twelve induced the jasmonic acid (JA) marker BdAOS. Additionally, resistance in Bd3–1 was unaffected by expression of the SA hydroxylase NahG. These results are consistent with previous findings that exogenous application of SA, JA, or ethylene fails to confer AG-4 resistance. Instead, most AG-4-resistant accessions showed common upregulation of cell wall biosynthesis-related genes following leaf infection, suggesting that cell wall fortification may contribute to defense against AG-4. These findings establish B. distachyon as a valuable model for dissecting resistance mechanisms against R. solani AG-4. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0289-0771 2026 Sex differences and contest experience shape walking patterns in the broad-horned flour beetle EN Kentarou Matsumura Graduate School of Arts and Sciences, The University of Tokyo Sora Hashioka Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Naohisa Nagaya Faculty of Information Science and Engineering, Kyoto Sangyo University Ryusuke Fujisawa Faculty of Environmental Engineering, University of Kitakyushu, Takahisa Miyatake Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Animal movement patterns vary widely across species, and sex differences are often expected because males typically need to encounter multiple females and acquire resources. In species where males engage in male–male combat using exaggerated weapons, variation in weapon size and contest outcomes is known to influence male reproductive strategies, and may therefore also affect movement behavior. However, sex-specific and male-specific differences in locomotor behavior, particularly in relation to weapon size and social interactions, remain poorly understood. Here, we investigated walking trajectories in the broad-horned flour beetle (Gnatocerus cornutus) to test for (1) sex differences, (2) associations between male weapon size and movement behavior, and (3) the effects of male–male combat. Males exhibited more tortuous and localized movement, whereas females showed straighter and more spatially extensive trajectories. Following contests, all males showed a reduction in activity regardless of contest outcome; however, winners and losers exhibited divergent changes in movement patterns, with winners showing straighter and more spatially extensive trajectories and losers showing more tortuous and localized trajectories. In contrast, body-size-corrected weapon size was not associated with any aspect of walking behavior. These results indicate that locomotor behavior in G. cornutus varies with sex and contest experience, and that variation in walking behavior is more closely associated with social experience than with weapon morphology. No potential conflict of interest relevant to this article was reported.

Fuji Technology Press Ltd. Acta Medica Okayama 1883-8030 21 1 2026 Developing and Implementing a Disaster Prevention Game to Enhance Local Understanding 128 135 EN Miri Shirokane Okayama University Airi Yamada Okayama University Ryo Misawa Okayama University Nobuhisa Matta Okayama University This study developed and implemented a local disaster prevention sugoroku-style game to address challenges in preserving and transmitting regional knowledge in areas with high population mobility. Many Japanese communities face both natural and social vulnerabilities, and effective disaster education requires linking hazard knowledge with local characteristics. Conducted at Sonan Junior High School in Okayama, the project combined lectures, workshops, and a community engagement event. Students learned about regional topography, land use, and disaster history and used this knowledge to design quizzes, rules, and disaster scenarios for the game. The final sugoroku set included a map-based board, thematic quiz areas, and preparedness item cards, enabling players to predict damage and consider appropriate actions. After creating the game, students shifted from identifying familiar landmarks to describing concrete disaster impacts such as liquefaction or infrastructure collapse. Interaction with local residents further enriched learning through shared experiences. The model proved feasible in terms of time and cost, and its structure is easily adaptable to other regions by incorporating local information. The findings suggest that this participatory, place-based approach enhances imagination, self-efficacy, and intergenerational knowledge transfer, contributing to community-wide disaster preparedness. Future studies will examine long-term educational impacts and broader regional applications. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2041-1723 17 1 2026 Atomic imaging for hydrogen and boron aggregates in boron-doped diamond by spectro-photoelectron holography 3482 EN Hiroto Tomita Graduate School of Science and Technology, Nara Institute of Science and Technology Wataru Hosoda Research Institute for Interdisciplinary Science, Okayama University Takumi Taniguchi Research Institute for Interdisciplinary Science, Okayama University Hirokazu Fujiwara Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo Noriyuki Kataoka Research Institute for Interdisciplinary Science, Okayama University Taisuke Kageura Sensing Technology Research Institute, National Institute of Advanced Industrial Science and Technology Yoshihiko Takano Research Center for Materials Nanoarchitectonics, National Institute for Materials Science Hiroshi Kawarada Faculty of Science and Engineering, Waseda University Tamio Oguchi Center for Spintronics Research Network, The University of Osaka Takayoshi Yokoya Research Institute for Interdisciplinary Science, Okayama University Tomohiro Matsushita Graduate School of Science and Technology, Nara Institute of Science and Technology The electrical properties of diamond are modulated by impurity doping. Isolated substitutional boron atoms introduce holes; however, the fraction of electrically inactive boron atoms increases at higher doping concentrations. This has been attributed to boron aggregation and hydrogen passivation, although their structural identification based on atomic arrangement has yet to be experimentally verified. Here we show the origin of multiple chemical states in homoepitaxially grown boron-doped diamond thin films by analyzing the atomic environment of boron using spectro-photoelectron holography. Our analysis identifies boron dimers and boron-hydrogen complexes, with hydrogen occupying different atomic sites that give rise to distinct chemical shifts. These results suggest that hydrogen incorporation during growth leads to passivation of boron acceptors. We demonstrate that photoelectron holography serves as a promising tool for imaging hydrogen as well as determining the atomic sites of dopants. No potential conflict of interest relevant to this article was reported.

Oxford University Press (OUP) Acta Medica Okayama 0032-0781 2026 NIMA-related kinases redundantly regulate vegetative and reproductive development in <i>Arabidopsis thaliana</i> pcag056 EN Shogo Takatani Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Mai Kanazawa Department of Biology, Faculty of Science, Okayama University Kotaro Sakamoto Department of Biology, Faculty of Science, Okayama University Yuki Tomita Graduate School of Biostudies, Division of Integrated Life Science, Kyoto University Nozomi Kawamoto Graduate School of Biostudies, Division of Integrated Life Science, Kyoto University Tatsuya Sakai Graduate School of Science and Technology, Niigata University Takashi Araki Graduate School of Biostudies, Division of Integrated Life Science, Kyoto University Hiroyasu Motose Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Never-in-mitosis A-related kinases (NEKs) are conserved protein kinases in eukaryotes that regulate cell division and elongation. In Arabidopsis thaliana, NEK6 has been shown to control anisotropic growth through cortical microtubule depolymerization, but the functions of other NEK family members remain largely unknown. Here, we show that Arabidopsis NEKs redundantly regulate organ growth and flowering through phosphorylation-dependent mechanisms. Expression analyses revealed overlapping promoter activities of NEK genes in meristems, vascular tissues, and floral organs. While most single mutants showed no obvious phenotype, multiple mutants exhibited defects in root growth direction, leaf elongation, vascular formation, and floral transition. Biochemical analysis showed that NEK3 and NEK6 phosphorylate both β-tubulin and γ-tubulin, indicating a conserved role in microtubule regulation. In addition, several NEKs interacted with the florigen FLOWERING LOCUS T (FT), and NEK3 phosphorylated FT in vitro and inhibited the FT–FD interaction in transient assays, suggesting a role in flowering regulation. These findings show that Arabidopsis NEKs redundantly coordinate vegetative and reproductive development through phosphorylation-dependent regulation of microtubules and the flowering pathway. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2041-1723 17 1 2026 The role of Pth1r in posterior cranium cartilage regulation and craniosynostosis 5862 EN Katsuhiko Amano Department of Oral and Maxillofacial Reconstructive Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Daisuke Okuzaki Laboratory of Human Immunology (Single Cell Genomics), WPI Immunology Frontier Research Center, University of Osaka Yuji Fujimoto Laboratory of Human Immunology (Single Cell Genomics), WPI Immunology Frontier Research Center, University of Osaka Yu-Chen Liu Laboratory of Human Immunology (Single Cell Genomics), WPI Immunology Frontier Research Center, University of Osaka Mikihiko Kogo The First Department of Oral and Maxillofacial Surgery, Osaka University Graduate School of Dentistry Seiji Iida Department of Oral and Maxillofacial Reconstructive Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Craniosynostosis is a major craniofacial congenital disorder that causes developmental complications. During normal cranial development, intramembranous ossification forms the flat bones and sutures, while cartilage appears transiently in the posterior calvarial region. However, in craniosynostosis, premature suture fusion disturbs normal calvarial morphogenesis. To clarify the role of transient cartilage in this morphogenetic disruption, we investigated its molecular regulation and pathology in mice, focusing on parathyroid hormone 1 receptor (Pth1r) signaling. Conditional deletion of Pth1r in the cranial mesenchyme unexpectedly caused acrocephalic dysmorphology and craniosynostosis, with altered cartilage differentiation. Occipito–interparietal synostosis consistently occurred in Pth1r-ablated Gli1+ and Acan+ lineages, but not after adult Gli1-CreERT2 deletion, indicating a developmental role. Bulk and single-cell RNA-seq analysis revealed nine mesenchymal subsets, with mutant cells showing abnormal chondrocyte differentiation and upregulated Indian hedgehog (Ihh) signaling. These findings indicate that Pth1r maintains proper chondrogenic regulation during calvarial development, and its loss induces craniosynostosis through Ihh overactivation. No potential conflict of interest relevant to this article was reported.

Oxford University Press (OUP) Acta Medica Okayama 0278-0372 46 3 2026 Estimating the distributional expansion of the invasive crayfish Procambarus clarkii (Girard, 1852) (Decapoda: Astacidea: Cambaridae) in South Korea using environmental DNA analysis ruag033 EN Seong-Nam Ham Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kaito Moriuchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Mayuko Hamada Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kazuyoshi Nakata Graduate School of Environmental, Life, Natural Science and Technology, Okayama University The red swamp crayfish Procambarus clarkii (Girard, 1852) is a globally invasive species that poses serious threats to native biodiversity and ecosystem functioning. In South Korea, established populations of P. clarkii have been documented from the Jiseokcheon River in the Yeongsangang River basin since 2018; however, information on its current nationwide distribution remains limited. We conducted environmental DNA (eDNA) surveys at 19 sites across 11 river systems in South Korea, including sites with no prior distributional records, to evaluate the current distribution and potential range expansion of P. clarkii. Water samples collected during July-August 2024 were analyzed using quantitative real-time PCR (qPCR) with two species-specific primer-probe sets targeting the mitochondrial COI gene. Procambarus clarkii eDNA was detected at three sites in the Yeongsangang River basin, whereas no eDNA was detected in the other surveyed river systems. Notably, P. clarkii eDNA was not detected at a site in the Mangyeonggang River system despite previous reports of individuals and eDNA data sampled there, indicating a possible local population decline or very low abundance. By contrast, detections within the Yeongsangang River basin, together with elevated eDNA concentrations at some sites, are consistent with localized upstream expansion and increased local abundance. The concordant results from the two primer-probe sets, together with Sterivex-based on-site filtration, support the reliability of the applied eDNA framework. These findings identify the Yeongsangang River basin as the current primary focus of the P. clarkii invasion in South Korea, with evidence consistent with localized upstream expansion and increasing abundance, and provide baseline data for early detection and long-term monitoring, as well as for developing management strategies. No potential conflict of interest relevant to this article was reported.

Institute of Electrical and Electronics Engineers (IEEE) Acta Medica Okayama 2187-0136 14 1 2025 Study of Signal Separation and Demodulation Techniques Considering IQ Imbalance by Stored Data Batch Signal Processing 30 33 EN Yudai Mita Graduate School of Natural Science and Technology, Okayama University Yuta Hiraoka Graduate School of Natural Science and Technology, Okayama University Tomofumi Hikasa Graduate School of Natural Science and Technology, Okayama University Shigeru Tomisato Graduate School of Natural Science and Technology, Okayama University Satoshi Denno Graduate School of Natural Science and Technology, Okayama University Kazuhiro Uehara Graduate School of Natural Science and Technology, Okayama University With the arrival of the IoT era, the problem of interference has become even more serious, and the challenge is to establish techniques for separating and demodulating collide signals. To achieve this, we are conducting research on stored data batch signal processing technology using short-time Fourier transform (STFT). In this paper, we used a feature quantity demodulation method proposed as a method for stored data batch signal processing to evaluate the effect of IQ imbalance, which is a factor in signal degradation in the transmitter, on signal separation and demodulation performance. Furthermore, we proposed a receiver configuration that estimates the amount of degradation due to IQ imbalance from the extracted feature quantities and compensates for the signal degradation. Computer simulation results confirmed that the proposed compensation method can improve signal separation and demodulation performance when degraded by IQ imbalance. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2041-1723 17 1 2026 Bacterial collagenase harnesses collagen geometry for processive cleavage 5485 EN Hiroya Oki Department of Infection Metagenomics, Genome Information Research Center, Research Institute for Microbial Diseases, The University of Osaka Katsuki Takebe Department of Dental Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Adjoa Bonsu Department of Chemistry and Biochemistry, University of Arkansas Kazunori Fujii Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University Ryo Masuda Waseda Research Institute for Science and Engineering, Waseda University Nicholas Henderson Department of Chemistry and Biochemistry, University of Arkansas Takehiko Mima Department of Medical Technology, Faculty of Health Sciences, Ehime Prefectural University of Health Sciences Takaki Koide Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University Mahmoud Moradi Department of Chemistry and Biochemistry, University of Arkansas Osamu Matsushita Department of Bacteriology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Joshua Sakon Department of Chemistry and Biochemistry, University of Arkansas Kazuki Kawahara Graduate School of Pharmaceutical Sciences, The University of Osaka Collagen, the major structural protein in the animal extracellular matrix, forms a triple helix that resists proteolysis and requires specialised enzymes for degradation. Flesh-eating bacteria secrete collagenases that unwind the collagen triple helix and processively trim Gly–X–Y triplet repeats, yet the molecular basis of this process has remained obscure. Here, cryo-electron microscopy reveals how Hathewaya histolytica collagenase ColH engages its substrate and exploits the helix’s architecture for catalysis. ColH encircles a single collagen triple helix in a closed-ring conformation and, through dynamic domain motions, dehydrates and destabilises it. The enzyme undergoes substrate-assisted twisting to adopt a rigid ratcheted conformation, in which one chain is bent into a tripeptide-long ‘bight’ and threaded into the active site for cleavage, while two uncut strands are partitioned to non-catalytic sites. Release of the bight appears to reset the enzyme, with the uncut strands serving as guiding tracks. Repeated cycling between dynamic and rigid states likely enables triplet-by-triplet translocation, allowing ColH to harness collagen’s geometry for processive degradation. These findings reveal a bacterial strategy for collagen unwinding and cleavage distinct from that of mammalian collagenases, highlighting divergent evolutionary solutions for degrading one of nature’s most intractable substrates. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2045-2322 16 1 2026 Dual-calibration RT-qPCR reveals distinct dnaK1/2/3 and groEL1/2 expression dynamics under heat and acid stress in the sinefungin producer Streptomyces incarnatus 19282 EN Zhao Xiao-Hui Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Mao Kubo Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haruka Yamagata Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuriko Nakashima Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tomohisa Hasunuma Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tadayoshi Kanao Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takashi Tamura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Streptomyces incarnatus NRRL8089 produces sinefungin, a nucleoside antibiotic whose yield is enhanced under defined environmental stresses. Here, dual-calibration RT-qPCR was used to resolve paralogue-specific expression dynamics of the dnaK and groE chaperone systems under heat and acid stress conditions that increase sinefungin titres. The canonical dnaK1–dnaJ1 and groES–groEL1 operons exhibited moderate induction, whereas monocistronic paralogues (dnaK2, dnaK3 and groEL2) showed markedly higher inducibility, with up to ~ 125-fold increases relative to baseline expression. Promoter analyses revealed conserved inverted repeats and differences in predicted secondary-structure stability, suggesting that promoter architecture contributes to paralogue-specific responsiveness. Structural modelling indicated divergence among DnaK paralogues in regions associated with substrate interaction, whereas GroEL paralogues retained a conserved overall scaffold, consistent with kinetic rather than structural differentiation. Together, these findings indicate that duplicated paralogues are not functionally redundant but are differentially regulated to partition proteostasis capacity under stress. This paralogue-specific regulation may provide a framework linking environmental perturbation to secondary-metabolite production in actinomycetes. No potential conflict of interest relevant to this article was reported.

Oxford University Press (OUP) Acta Medica Okayama 2977-0548 2 3 2026 Truncation by death in the sufficient-cause framework uuag021 EN Bronner P Gonçalves Faculty of Health and Medical Sciences, University of Surrey Eiji Yamamoto Okayama University of Science Etsuji Suzuki Department of Epidemiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University The sufficient-cause framework has been used for decades to improve our understanding of both basic and complex causal concepts in epidemiology, such as mediation and interaction. Here, we make use of this framework to provide a description of truncation by death, in which the outcome of interest is undefined for individuals who die before the assessment time at the end of follow-up. We explain the noncausal nature of the crude estimand that compares outcomes by treatment levels conditional on observed survival by showing that it corresponds to a comparison of distinct risk-status types, which are defined based on their susceptibility to sufficient causes. Further, expressions for the crude estimand and for the survivor average causal effect (SACE)—a causal estimand defined under the principal stratification approach—are provided in terms of population-level joint frequencies of the background factors of sufficient causes. Finally, we also describe conditions, based on background factors of sufficient causes, under which the SACE is null. Our description of this problem, which studies truncation by death from a new perspective, might encourage further analyses of principal stratification-based estimands using sufficient causes. No potential conflict of interest relevant to this article was reported.

Japanese Society of Veterinary Science Acta Medica Okayama 0916-7250 87 6 2025 Effects of heat stress on gene expression associated with antioxidant capacity of bovine early antral follicles 680 684 EN Kohei KAWANO Laboratory of Reproductive Physiology, Faculty of Environmental, Life, Natural Science and Technology, Okayama University Kenichiro SAKAGUCHI Laboratory of Veterinary Theriogenology, Joint Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University Eri FURUKAWA National Institute of Animal Health, National Agriculture and Food Research Organization Nattapong NINPETCH Department of Animal Science, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University Yojiro YANAGAWA Laboratory of Theriogenology, Department of Clinical Sciences, Division of Veterinary Medicine, Faculty of Veterinary Medicine, Hokkaido University Seiji KATAGIRI Laboratory of Theriogenology, Department of Clinical Sciences, Division of Veterinary Medicine, Faculty of Veterinary Medicine, Hokkaido University Heat exposure at the physiological level of oocyte-cumulus-granulosa cell complexes (OCGCs) during in vitro growth (IVG) culture decreases the reduced glutathione (GSH) level of oocytes, an antioxidant, but its mechanism has been unclear. We subjected OCGCs to IVG for 4, 8, or 12 days and investigated the effects of heat exposure on the gene expression of cumulus-granulosa cells associated with antioxidant capacity. Heat exposure did not alter the expression of genes related to GSH synthesis or reuse. Conversely, heat exposure increased mRNA expression of superoxide dismutase 2 and decreased that of glutathione peroxidase 1, which are antioxidant enzymes. Ultimately, heat exposure alters the gene expression of antioxidant enzymes in growing follicles, which may indirectly decrease the GSH level of oocytes. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0743-7463 40 52 2024 Formation of Nonspherical Cellulose Acetate Microparticles under Microflow 27314 27322 EN Kurumi Mori Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takaichi Watanabe Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tsutomu Ono Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nonspherical particles have gained significant interest owing to their unique shapes and large specific surface areas, making them suitable for a wide range of applications, such as drug delivery, catalysis, and adsorption. However, conventional methods for preparing nonspherical particles face certain limitations. In this study, we propose a simple method for fabricating nonspherical cellulose acetate (CA) microparticles using a microfluidic device in which droplets undergo rapid diffusion in a continuous aqueous phase. The influence of variations in the flow rate ratio and continuous phase composition on the dimensionless Péclet number (Pe) within the droplet and shape of the resultant particles is investigated. Pe is critical, because it indicates the balance between polymer diffusion and droplet shrinkage dynamics. Our findings reveal that increasing the flow rate ratio and reducing the methyl acetate concentration in the continuous phase lead to faster droplet shrinkage and an increased Pe. A high Pe (>100) suggests that the reduction of the droplet interface predominates over polymer diffusion, resulting in the formation of a viscous layer near the droplet surface, which subsequently leads to nonspherical particle shapes (such as bowl-like or biconcave structures). In situ time-lapse observations of droplets from the top and side of a microchannel reveal that the formation of a viscous layer near the droplet surface and the deformation of the droplet, influenced by the z-axis location of the droplets during particle formation, ultimately determine the final particle shape. Based on these observations, a linear correlation between the initial conditions, i.e., the Pe and z-axis location at which the viscous layer formed, is established, enabling the prediction of the particle structure. In summary, the present study enhances the understanding of shape control in microfluidic particle formation and offers a novel guideline for the fabrication of spherical and nonspherical particles. No potential conflict of interest relevant to this article was reported.

Oxford University Press (OUP) Acta Medica Okayama 1347-6947 88 10 2024 Evaluation of quercetin as a potential cytoprotector against acetaldehyde using the cultured hepatocyte model with aldehyde dehydrogenase isozyme deficiency 1199 1202 EN Yuhang Xu Graduate School of Environmental and Life Science, Okayama University Takeshi Sawamoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Ruitong Sun Graduate School of Environmental and Life Science, Okayama University Aki Ishikura Graduate School of Environmental and Life Science, Okayama University Shintaro Munemasa Graduate School of Environmental and Life Science, Okayama University Yoshiyuki Murata Graduate School of Environmental and Life Science, Okayama University Ayano Satoh Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Akiko Matsumoto Department of Social and Environmental Medicine, Saga University Toshiyuki Nakamura Graduate School of Environmental and Life Science, Okayama University Yoshimasa Nakamura Graduate School of Environmental and Life Science, Okayama University Protective effect of quercetin against acetaldehyde was evaluated using the cultured hepatocyte models with aldehyde dehydrogenase (ALDH) isozyme deficiency (aldh2-kd and aldh1a1-kd). The quercetin-induced cytoprotection against acetaldehyde in the ALDH1A1-deficient mutant (aldh1a1-kd) was weaker than that in the wild type. Furthermore, quercetin did not enhance the ALDH activity in aldh1a1-kd cells, suggesting that ALDH1A1 is involved in quercetin-induced cytoprotection. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2050-7488 13 11 2025 Enhanced capacity of aluminum-ion batteries by adjusting the average pore size of the porous carbon cathode 8052 8058 EN Yifeng Chen Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Hiroo Suzuki Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Shu Fukumoto Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Chiyu Nakano Department of Comprehensive Technical Solutions, Okayama University Takeshi Nishikawa Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Shigeyuki Umezawa Seiwa Electric Mfg. Co., Ltd Yasuhiko Hayashi Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Lithium-ion batteries (LIBs) are widely used but with the increasing scarcity and uneven distribution of global lithium resources, there is a need to explore alternative battery technologies. Due to its abundance, low cost, and high theoretical capacity, aluminum is a strong candidate for metal anodes, making aluminum-ion batteries (AIBs) an area of considerable interest. Current mainstream research focuses on ionic liquid electrolytes, which offer a wide electrochemical window and high ionic conductivity. Carbon materials are ideal cathode candidates due to their low cost, abundance, and high voltage platform. AIBs using carbon materials typically exhibit low discharge capacity. This study addressed the challenge of improving the discharge capacity of carbon-based cathodes in AIBs. By using porous carbon (PC) materials with varying specific surface areas, average pore sizes, and total pore volumes as cathodes, average pore size was found to impact capacity. This contradicts the contention that larger specific surface areas result in higher capacities. There is a key difference in ion behavior: whereas aluminum chloride ions intercalate into layered graphite structures, they do not intercalate into PC materials but are adsorbed to the surface. By adjusting the average pore size, it is possible to increase the discharge capacity of AIBs, challenging the traditional emphasis on specific surface area. This research does not fully solve the problem of low discharge capacity in carbon-based cathodes, but provides a new perspective on the role of pore size in enhancing battery performance, offering valuable insights for future electrode design. No potential conflict of interest relevant to this article was reported.

Oxford University Press (OUP) Acta Medica Okayama 0366-7022 54 5 2025 Highly emissive and robust diarylethene fluorophore incorporating imide-fused phenanthryl moieties upaf091 EN Keito Nose Department of Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Minoru Yamaji Program of Applied Chemistry, Cluster of Materials and Environment, Gunma University Tadashi Mori Research Center for Environmental Preservation and Graduate School of Engineering, The University of Osaka Fumito Tani Institute for Materials Chemistry and Engineering, Kyushu University Kenta Goto Institute for Materials Chemistry and Engineering, Kyushu University Hideki Okamoto Department of Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University The fluorescence properties and photostabilities of (E)-diarylethenes (DPEs), featuring two 3-phenanthryl moieties, were investigated. Pristine (E)-di-1,2-(3-phenanthryl)ethene and its ester derivative, respectively referred to as DPE-H and DPE-E, exhibited blue fluorescence. However, they underwent a two-step photoreaction sequence that yielded [7]helicenes, resulting in a gradual reduction of the fluorescence intensity. In contrast, the imide-fused derivative DPE-I displayed intense green fluorescence and it was unexpectedly photostable in solution, maintaining its highly efficient fluorescent nature even after prolonged light exposure. DPE-I, thus, provides a new type of highly efficient and robust diarylethene fluorophore. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1477-0520 22 46 2024 A direct oxidative esterification of aldehydes with alcohols mediated by photochemical C–H bromination 9032 9035 EN Haru Ando Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Sakura Kodaki Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Hiroyoshi Takamura Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Isao Kadota Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Kenta Tanaka Research Institute for Interdisciplinary Science, Okayama University The photochemical direct esterification of aldehydes with alcohols via in situ-generated acyl-bromides presented in this report is an attractive complementary addition to hitherto reported methods, as these are usually carried out in a two-step, one-pot procedure in order to avoid side reactions such as the oxidation of alcohols by halogen sources. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1086-9379 59 12 2024 Radial transport and nebular thermal processing of millimeter‐sized solids in the Solar protoplanetary disk inferred from Cr‐Ti‐O isotope systematics of chondrules 3282 3304 EN Kohei Fukuda WiscSIMS, Department of Geoscience, University of Wisconsin-Madison Yuki Hibiya Research Center for Advanced Science and Technology, Graduate School of Science, The University of Tokyo Craig R. Kastelle National Oceanic and Atmospheric Administration Katsuhiko Suzuki Submarine Resources Research Center, Japan Agency for Marine-Earth Science Technology Tsuyoshi Iizuka Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo Katsuyuki Yamashita Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Thomas E. Helser National Oceanic and Atmospheric Administration Noriko T. Kita WiscSIMS, Department of Geoscience, University of Wisconsin-Madison Understanding the material transport and mixing processes in the Solar protoplanetary disk provides important constraints on the origin of chemical and isotopic diversities of our planets. The limited extent of radial transport and mixing between the inner and outer Solar System has been suggested based on a fundamental isotopic dichotomy between non-carbonaceous (NC) and carbonaceous (CC) meteorite groups. The limited transport and mixing could be further tested by tracing the formation regions of individual meteoritic components, such as Ca-Al-rich inclusions (CAIs) and chondrules. Here, we show further evidence for the outward transport of CAIs and chondrules from the inner and subsequent thermal processing in the outer region of the protoplanetary disk based on the petrography and combined Cr-Ti-O isotope systematics of chondrules from the Vigarano-like (CV) carbonaceous chondrite Allende. One chondrule studied consists of an olivine core that exhibits NC-like Ti and O, but CC-like Cr isotopic signatures, which is enclosed by a pyroxene igneous rim with CC-like O isotope ratios. These observations indicate that the olivine core formed in the inner Solar System. The olivine core then migrated into the outer Solar System and experienced nebular thermal processing that generated the pyroxene igneous rim. The nebular thermal processing would result in Cr isotope exchange between the olivine core and CC-like materials, but secondary alteration effects on the parent body are also responsible for the CC-like Cr isotope signature. By combining previously reported Cr-Ti-O isotope systematics of CV chondrules, we show that some CV chondrules larger than ~1 mm would have formed in the inner Solar System. The accretion of the millimeter-sized, inner Solar System solids onto the CV carbonaceous chondrite parent body would require their very early migration into the outer Solar System within the first 1 million years after the Solar System formation. No potential conflict of interest relevant to this article was reported.

Department of Mathematics, Faculty of Science, Okayama University Acta Medica Okayama 0030-1566 68 1 2026 On groups of units of commutative finite rings 77 87 EN Chiteng’a John Chikunji Department of Biometry and Mathematics, Botswana University of Agriculture and Natural Resources Let R be a commutative completely primary finite ring with unique maximal ideal J such that J3 = {0} and J2 ̸= {0}. In this paper, we investigate and determine the structure of the group of units U(R) of the ring R of characteristic p3 without giving any conditions on the generators for the maximal ideal J or on the invariants of the ring R. No potential conflict of interest relevant to this article was reported.

Department of Mathematics, Faculty of Science, Okayama University Acta Medica Okayama 0030-1566 68 1 2026 Natural homotopy of multipointed d-spaces 13 62 EN Philippe Gaucher Université Paris Cité, CNRS, IRIF We identify Grandis’ directed spaces as a full reflective subcategory of the category of multipointed d-spaces. When the multipointed d-space realizes a precubical set, its reflection coincides with the standard realization of the precubical set as a directed space. The reflection enables us to extend the construction of the natural system of topological spaces in Baues-Wirsching’s sense from directed spaces to multipointed d-spaces. In the case of a cellular multipointed d-space, there is a discrete version of this natural system which is proved to be bisimilar up to homotopy. We also prove that these constructions are invariant up to homotopy under globular subdivision. These results are the globular analogue of Dubut’s results. Finally, we point the apparent incompatibility between the notion of bisimilar natural systems and the q-model structure of multipointed d-spaces and we give some suggestions for future works. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0960-9822 36 5 2026 Compound starch granule formation in grass seeds is associated with distinct temporal patterns of gene expression 1142 1155.e6 EN Alexander Watson-Lazowski John Innes Centre, Norwich Research Park Doreen Feike John Innes Centre, Norwich Research Park Qi Yang Ngai John Innes Centre, Norwich Research Park Lara Esch John Innes Centre, Norwich Research Park Naoko Fujita Department of Biological Production, Akita Prefectural University Ryo Matsushima Institute of Plant Science and Resources, Okayama University Alison M. Smith John Innes Centre, Norwich Research Park David Seung John Innes Centre, Norwich Research Park There is extensive interspecies variation in starch granule morphology in the endosperm of grass species, but the factors underpinning this variation are poorly understood. The two major granule morphology types among species are simple and compound granules, where simple granules arise from a single initiation per amyloplast, and compound granules form from multiple granule initiations. Here, we carried out an extensive survey of seed starch morphology, examining specimens from 105 species within the Pooideae using electron microscopy. This not only expanded our current knowledge of the diversity of starch granule types but also confirmed the homoplasy of simple and compound starch granules. We then selected species representing independent origins of simple (Brachyelytrum japonicum, Phaenosperma globosa, and Brachypodium distachyon) and compound granules (Nardus stricta, Melica altissima, and Calamagrostis brachytricha) for analysis of starch structure and gene expression. There were no clear patterns in starch content, amylopectin structure, or amylose content that could distinguish the two granule types. However, comparative transcriptomics over seed development revealed gene expression patterns associated with granule type, most notably increasing expression of STARCH SYNTHASE 3a (SS3a), STARCH BRANCHING ENZYME 1 (SBE1), and limit dextrinases (LDAs) between 3 and 9 days post anthesis in species with compound granules. Mutation of these genes in rice, which natively produces compound granules, resulted in altered granule shape and/or size. Our work highlights differences in gene expression that could contribute to natural variation in granule morphology within the Pooideae while providing important new starch phenotype and gene expression datasets that can be widely used to study endosperm development. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2637-6105 8 11 2026 Solution Structure and Counterion Condensation of Carboxymethyl Cellulose in Organic Solvents 8183 8197 EN Anish Gulati Institute of Physical Chemistry, RWTH Aachen University Lingzi Meng Materials Science and Engineering Department, The Pennsylvania State University Can Hou Institute of Physical Chemistry, RWTH Aachen University Takaichi Watanabe Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Carlos G. Lopez Materials Science and Engineering Department, The Pennsylvania State University We report scattering (SANS and SAXS) and electrical conductivity data for aqueous and organic solutions of carboxymethyl cellulose with tetrabutylammonium counterions. For SANS in deuterated solvents, the contrast is heavily dominated by the hydrogen-rich counterions, while for SAXS the polymer backbone has a more significant contribution to the scattering signal. The correlation length calculated from the SAXS measurements follows a scaling law of ξ ∝ c–1/2, while that measured by SANS displays a weaker exponent at higher concentrations for solvents of high dielectric constants. These results indicate a decoupling in the characteristic length scales of fluctuations of the polymer backbone and counterions at high polyelectrolyte concentrations. The stretching parameter calculated from the correlation length indicates a highly stretched local conformation for TBACMC in water and several high dielectric constant solvents, consistent with the semiflexible nature of the cellulose backbone. In solvents of lower dielectric permittivity, the chains display a higher degree of local coiling. Combining electrical conductivity and scattering data, we find that the fraction of monomers bearing a dissociated charge is nearly independent of concentration and approximately proportional to the reciprocal of the Bjerrum length of the solvent, as expected by the Oosawa-Manning model. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2041-1723 16 1 2025 Grain boundary diffusion cannot explain the W isotope heterogeneities of the deep mantle 1866 EN Yihang Peng Department of Geosciences, Princeton University Takashi Yoshino Institute for Planetary Materials, Okayama University Jie Deng Department of Geosciences, Princeton University The low 182W/184W and high 3He/4He in some ocean island basalts compared to the bulk mantle values may derive from the Earth’s core through long-term core-mantle interactions. It has been proposed that the grain boundary diffusion of siderophile elements is an efficient mechanism for core-mantle interaction and may effectively modify the W isotopic compositions of the plume-source mantle. In this study, we perform large-scale molecular dynamics simulations driven by machine learning potentials of ab initio quality to investigate the diffusion of W along ferropericlase grain boundaries and in (Mg,Fe)O liquid. Here we show that the diffusion of W is sluggish under core-mantle boundary conditions, and thus is unlikely to have observable impacts on the W isotopic compositions of terrestrial igneous rocks. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2041-1723 16 1 2025 Low melt viscosity enables melt doublets above the 410-km discontinuity 3239 EN Longjian Xie Center for High Pressure Science & Technology Advanced Research Denis Andrault Université Clermont Auvergne, CNRS, IRD, OPGC, Laboratoire Magmas et Volcans Takashi Yoshino Institute for Planetary Materials, Okayama University Cunrui Han School of Natural Sciences, Birkbeck, University of London James O. S. Hammond School of Natural Sciences, Birkbeck, University of London Fang Xu School of Earth Sciences, Zhejiang University Bin Zhao Institute for Planetary Materials, Okayama University Oliver T. Lord School of Earth Sciences, University of Bristol Yingwei Fei Earth & Planets Laboratory, Carnegie Institution for Science Simon Falvard Université Clermont Auvergne, CNRS, IRD, OPGC, Laboratoire Magmas et Volcans Sho Kakizawa Japan Synchrotron Radiation Research Institute Noriyoshi Tsujino Japan Synchrotron Radiation Research Institute Yuji Higo Japan Synchrotron Radiation Research Institute Laura Henry Synchrotron SOLEIL Nicolas Guignot Synchrotron SOLEIL David P. Dobson Department of Earth Sciences, University College London Seismic and magnetotelluric studies suggest hydrous silicate melts atop the 410 km discontinuity form 30–100 km thick layers. Importantly, in some regions, two layers are observed. These stagnant layers are related to their comparable density to the surrounding mantle, but their formation mechanisms and detailed structures remain unclear. Here we report a large decrease of silicate melt viscosity at ~14 GPa, from 96(5) to 11.7(6) mPa⋅s, as water content increases from 15.5 to 31.8 mol% H₂O. Such low viscosities facilitate rapid segregation of melt, which would typically prevent thick layer accumulation. Our 1D finite element simulations show that continuous dehydration melting of upwelling mantle material produces a primary melt layer above 410 km and a secondary layer at the depth of equal mantle-melt densities. These layers can merge into a single thick layer under low density contrasts or high upwelling rates, explaining both melt doublets and thick single layers. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 1756-4646 126 2025 Proteome analysis reveals the molecular mechanisms of fucoxanthin-induced apoptosis in glial cells PC12 after nanoencapsulation 106710 EN Chunyan Wang School of Food Science, Henan Institute of Science and Technology Xinxin Ma School of Food Science, Henan Institute of Science and Technology Yoshimasa Nakamura Graduate School of Environmental and Life Science, Okayama University Hang Qi SKL 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 University Fucoxanthin (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.

Springer Science and Business Media LLC Acta Medica Okayama 2045-2322 16 1 2026 Boulder populations and orientation trends on asteroid Ryugu: implications for rubble-pile surface processes 14404 EN Aditya Ray Institute for Planetary Materials, Okayama University Trishit Ruj Institute for Planetary Materials, Okayama University Goro Komatsu International Research School of Planetary Sciences, Università G. d‘Annunzio Lisa M. Vincent Department of Earth Sciences, Utrecht University Hiroshi Kikuchi Gakushuin University Ryodo Hemmi Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency Jens Ormö Centro de Astrobiología (CAB), CSIC-INTA Asteroid (162173) Ryugu is a spinning-top shaped, rubble-pile C-type asteroid with a surface dominated by boulders spanning a broad size-range. Using Hayabusa2 ONC-T mosaics for mapping, we present the most extensive global boulder dataset to date, representing an eleven-fold increase over the earliest survey and greater completeness than later AI-based estimates. Crucially, this work provides the first global boulder orientation dataset. The cumulative size-frequency distribution follows a power-law slope of − 2.665 ± 0.066 (boulders ≥ 3 m), indicating its fragmented nature. Boulder density is lower along the equatorial ridge, consistent with regolith accumulation during earlier YORP-driven spin-up and poleward migration of blocks during the present spin-down phase. Orientation analyses reveal systematic hemispheric trends in what we define as slope-breaker zones (i.e., regions of high slope differentials), with NW–SE alignment in the northern hemisphere and NE–SW in the southern hemisphere, but absent at the equatorial ridge and poles. We interpret these as reorientations that developed during downslope boulder migration, as despite ongoing spin-down, the current spin rate remains high enough to drive such motion. In addition, fresh craters exhibit locally heightened boulder densities, recording ongoing resurfacing by impact events that exhume buried subsurface boulders and segregate them from finer regolith via seismic shaking induced granular convection. Together, these results yield new insights into rubble-pile surface evolution, rotational dynamics, and impact-driven resurfacing, with boulder orientations providing critical evidence of spin-related downslope transport and establish a framework for comparative asteroid studies. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0883-2927 207 2026 Effects of secondary hydrothermal fluids on gallium distribution and coordination in hot springs silica using Ga K-edge XANES 106961 EN M.C. Rowe School of Environment, University of Auckland K.A. Campbell School of Environment, University of Auckland D.A. Stallard School of Environment, University of Auckland B. Lyon School of Environment, University of Auckland A. Langendam Australian Synchrotron Facility (Ansto) E. Kalinina The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University M. Yamanaka The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University R. Tanaka The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University T. Christopher School of Chemical Sciences, University of Auckland S.W. Ruff Arizona State University, School of Earth And Space Exploration E. Nersezova School of Environment, University of Auckland T. Ota The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University A. Hamilton School of Environment, University of Auckland Gallium (Ga), a critical element in the electronics industry, is enriched in hot spring silica deposits (sinter) at concentrations comparable to, and in some cases greater than, bauxite, coal, and sphalerite deposits from which it is currently extracted. Focusing on well characterized Holocene and Pleistocene New Zealand sinters, we utilize synchrotron-X-ray fluorescence (sXRF) and Ga K-edge X-ray absorption near edge structure (XANES) spectroscopy to examine the spatial distribution of Ga as well as its changing coordination number. Ga+3 is the only observed oxidation state in the analyzed sinters. Gallium is predominantly found in tetrahedral coordination in sinter deposited from alkali chloride fluids, with analyses best matching Ga-aluminosilicate standards. However, Ga coordination is octahedral in sinter samples that have undergone alteration by acidic fluids/gases, associated with a change in hydrology from alkali-chloride to acid-sulfate fluid conditions. High Ga concentrations are found associated with both these coordination environments, with a heterogeneous distribution. Octahedral Ga is observed both as particles and in larger regions affected by Fe-rich fluid overprinting. The combined use of sXRF and XANES demonstrates an ability to fingerprint diagenesis and alteration in these complex geothermal settings where tetrahedral and octahedral Ga co-exist. The transition from tetrahedral to octahedral Ga also appears to mimic the inferred natural process forming lateritic bauxite deposits, where remobilized tetrahedral Ga is reconcentrated and adsorbed to oxides. A similar process may occur for sinter Ga enrichment, whereby introduced Ga in acidic conditions is adsorbed to oxide phases as the Fe-rich secondary fluids infiltrate porous sinter material. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 3042-6081 2 2 2026 Interfacial Bond Strength of Resin Cement to Polyetheretherketone (PEEK) Using Experimental Primers Doping Multifunctional Methacrylate and Acrylate Monomers 12 EN Yukinori Maruo Department of Prosthodontics, Okayama University Kumiko Yoshihara Health Research Institute, National Institute of Advanced Industrial Science and Technology Masao Irie Okayama University Dental School Noriyuki Nagaoka Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School Naoki Kodama Department of Prosthodontics, Okayama University Yuki Tanaka Department of Occlusal and Oral Functional Rehabilitation, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Miho Kuwahara Department of Occlusal and Oral Functional Rehabilitation, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kentaro Akiyama Department of Occlusal and Oral Functional Rehabilitation, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Polyetheretherketone (PEEK) is a high-performance thermoplastic polymer with low surface energy, chemical inertness, and a highly crystalline structure, which limit durable adhesion to resin-based materials and require improved bonding strategies. This in vitro study evaluated the effect of incorporating multifunctional methacrylate (TMPTMA) and acrylate monomers (A-TMPT and A-DPH) into an experimental primer on the 24 h shear bond strength (SBS) of resin cement to PEEK (n = 6 per group). Experimental primers were prepared by adding varying amounts (100–500 µL) of each multifunctional monomer to a UDMA/MMA-based primer, and SBS was measured after cementation with a dual-cure resin cement. TMPTMA-containing primers produced median SBS values of approximately 10–12 MPa, while acrylate-based primers showed slightly higher values, particularly at higher concentrations, reaching up to ~15.8 MPa; however, no statistically significant improvement over the control group was observed (p > 0.05). Failure modes were predominantly mixed across all conditions. These findings indicate that multifunctional monomers, despite their potential to enhance cross-link density and wetting, do not substantially overcome the intrinsic adhesion-resistant nature of polished PEEK. The results underscore that monomer modification alone is insufficient and that effective adhesion to PEEK likely requires integrated strategies combining chemical activation with mechanical surface conditioning. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2075-1729 16 6 2026 Disease-Suppressive Activity of Lecithin Against Foliar Infection by Rhizoctonia solani Isolates in Cabbage, Rice, and Brachypodium distachyon 998 EN Tran Xuan Cuong Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Misaki Asano School of Agriculture, Okayama University Daiki Honma School of Agriculture, Okayama University Moeko Soeda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Megumi Watanabe Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nanami Sakata Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hidenori Matsui Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kazuhiro Toyoda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, Okayama 700-8530, Japan Yuki Ichinose Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kentaro Ikeda Faculty of Bioscience and Applied Chemistry, Hosei University Yoshiteru Noutoshi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Rhizoctonia solani is a necrotrophic phytopathogenic fungus that causes disease in various crops. In agriculture, many crops suffer from root or seedling rot caused by this soil-borne pathogen, whereas cabbage and rice develop lesion-like symptoms on aboveground tissues. Diseases caused by R. solani are generally controlled using chemical fungicides; however, environmentally friendly alternatives are needed for sustainable agriculture. In this study, we evaluated the efficacy of lecithin, a mixture of phospholipids previously registered in Japan as an agrochemical for controlling cucumber powdery mildew, against Rhizoctonia diseases. In cabbage, foliar spraying of 0.2–1.0% soybean lecithin effectively suppressed leaf symptoms caused by R. solani isolate RhiCa-2, which was identified as AG-1 IB. In rice and Brachypodium distachyon, 0.2–1.0% lecithin significantly suppressed leaf symptoms induced by R. solani AG-1 IA. Hyphal staining of inoculated leaves revealed reduced hyphal density on lecithin-treated leaves. Consistently, hyphal growth of R. solani on cellophane placed on water agar was retarded by lecithin treatment. However, 5.0% lecithin induced phytotoxicity in B. distachyon. Egg yolk-derived lecithin also exhibited disease-suppressive activity in cabbage and B. distachyon, with efficacy comparable to that of soybean lecithin under the conditions tested. These results suggest that lecithin suppresses foliar infection by R. solani, at least in part, through direct inhibitory effects on fungal hyphae, and may serve as a potential alternative material for disease control in sustainable crop production. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2075-1729 16 6 2026 UGT76B1 and 41 Additional Arabidopsis UDP-Glycosyltransferases Show No Detectable In Vitro Glycosylation Activity Toward N-Hydroxypipecolic Acid 992 EN Jiyuan Bao Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Taiga Uchiyama Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kazuki Kusunoki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuka Shinohara Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yurika Tanigawa School of Agriculture, Okayama University Megumi Watanabe Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nanami Sakata Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hidenori Matsui Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kazuhiro Toyoda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuki Ichinose Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yoshiteru Noutoshi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University N-hydroxypipecolic acid (NHP) is a key mobile signal in systemic acquired resistance in plants, and its glycosylation has been proposed to regulate immune signaling. Previous studies have demonstrated that the UDP-glycosyltransferase UGT76B1, known as an SA glycosyltransferase in Arabidopsis thaliana, also catalyzes NHP glycosylation. In this study, we re-evaluated NHP glycosylation activity of UGT76B1 using an in vitro enzyme-coupled fluorescence assay that quantitatively detects UDP released during UDP-sugar-dependent glycosylation. Unexpectedly, our biochemical analyses demonstrated that UGT76B1 lacks genuine glycosylation activity toward NHP under the in vitro assay conditions tested, although this system clearly detected UGT76B1 activity toward salicylic acid (SA), as well as the activities of UGT74F1 and UGT72B1 toward SA and hydroquinone, respectively. To explore potential UGTs responsible for NHP glycosylation, we evaluated the enzymatic activities of 41 UGT candidates successfully expressed in Escherichia coli, which are selected based on transcriptomic responses to tenoxicam treatment, molecular docking simulations using AlphaFold3/AutoDock Vina, phylogenetic criteria, and previous reports. Within this selected and successfully expressed UGT panel, none exhibited authentic NHP glycosylation activity, although this does not preclude the possibility that other members of the Arabidopsis UGT family possess NHP glycosyltransferase activity. Our findings challenge the prevailing view that UGT76B1 is the primary glycosyltransferase for NHP in A. thaliana and indicate that NHP metabolism may rely on undiscovered non-canonical enzymes or distinct metabolic pathways that warrant further investigation. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 1999-5903 18 6 2026 A Batch-Based VNF Deployment Mechanism for Privacy-Preserving Multi-Domain SFC Deployment Using Deep Reinforcement Learning 312 EN Arif Indra Irawan Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yukinobu Fukushima Faculty of Environmental, Life, Natural Science and Technology, Okayama University Future 6G networks require higher performance and wider service coverage. Multi-domain Service Function Chain (SFC) deployment enables service provisioning across multiple network domains to meet these demands. However, when collaboration occurs among different network operators, privacy-preserving mechanisms are required to protect sensitive information such as internal topology and resource availability. Existing SIRM-based mechanisms, such as the Privacy-Preserving Deployment Mechanism (PPDM), address this challenge but suffer from structural limitations: PPDM performs whole-chain feasibility evaluation with extensive virtual occupation. This paper proposes a ℬ-Batch Sequential Deployment mechanism for privacy-preserving multi-domain SFC deployment. Instead of evaluating whole-chain feasibility at once, the proposed ℬ-Batch mechanism partitions each incoming SFC into fixed-size VNF batches and constructs a batch-level SIRM. This design confines virtual occupation to the current batch and reduces both its magnitude and duration while remaining fully compatible with the SIRM privacy model and the hierarchical multi-domain control architecture. A Deep Q-Network (DQN) is employed to learn substrate node selection policies based solely on SIRM-based state information, without exposing domain-internal topology or resource details. Simulation results on a three-domain AARNET substrate topology demonstrate that the proposed mechanism consistently improves deployment robustness under varying traffic intensities and SFC lengths, including short (3–6 VNFs), medium (6–9 VNFs), and long (9–12 VNFs) service chains. Compared with PPDM, the proposed ℬ-Batch mechanism achieves higher acceptance ratios under moderate-to-heavy traffic while reducing end-to-end delay and improving average substrate resource utilization. Node selection analysis further shows that smaller batch sizes preserve feasibility through compact node reuse, whereas larger batch sizes encourage broader substrate exploration. Overall, the proposed ℬ-Batch mechanism enhances feasibility preservation and deployment robustness in privacy-preserving multi-domain SFC orchestration. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 80 3 2026 Oral Eicosapentaenoic Acid and Paclitaxel-Associated Peripheral Neuropathy: A Retrospective Study at Okayama University Hospital 179 184 EN Ayako Morita Center for Clinical Oncology, Okayama University Hospital Hideki Katayama Center for Clinical Oncology, Okayama University Hospital Eiki Ichihara Center for Clinical Oncology, Okayama University Hospital Yoshinobu Maeda Department of Hematology and Oncology, Okayama University Hospital Original Article 10.18926/AMO/70853 This retrospective study investigated whether eicosapentaenoic acid (EPA) reduces paclitaxel-associated chemotherapy-induced peripheral neuropathy (CIPN) and acute neuropathic pain in dyslipidemic cancer patients. The medical records of cancer patients treated with paclitaxel or nab-paclitaxel at Okayama University Hospital between January 2018 and December 2022 were reviewed. Patients receiving concomitant therapy for dyslipidemia were categorized as EPA users or non-EPA users. Numbness and pain severity were extracted from medical records. The primary endpoint was the change from baseline in Common Terminology Criteria for Adverse Events (CTCAE) grade for peripheral neuropathy and pain; groups were analyzed using the Mann–Whitney U test. Of 184 eligible patients, 18 received EPA. Bleeding events were more frequent in the EPA group; however, changes in numbness and pain did not differ significantly between groups at any time point. Overall, EPA did not show a preventive effect on paclitaxel-associated CIPN or acute neuropathic pain. Future studies should evaluate EPA in combination with other neuroprotective agents to better define its potential role in CIPN prevention. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0721-832X 2026 Age-related changes in the orbital pulley array of older Japanese adults with acquired exotropia EN Reika Kono Department of Ophthalmology,, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Ichiro Hamasaki Lino Eye Clinic Fumiko Kishimoto Division of Ophthalmology, Ibara City Hospital Kiyo Shibata Lino Eye Clinic Shin Morisawa Department of Ophthalmology,, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Yuki Morizane Department of Ophthalmology,, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Purpose: To evaluate age-related changes in the orbital pulley array using magnetic resonance imaging (MRI) in older Japanese adults with acquired exotropia (XT) compared with young healthy participants (YHP).<br> Methods: In this retrospective cross-sectional case series, MRI images of 30 eyes from fifteen patients (age ≥ 60 years) with distance XT and no high myopia were compared with those of 14 eyes from seven YHP. Rectus muscle (RM) pulley positions relative to the globe center were assessed. The lateral rectus muscle–superior rectus (LR–SR) band was evaluated for rupture.<br> Results: Mean age of patients with XT was 73.7 ± 5.5 years. Compared with YHP, patients with XT showed significant inferior displacement of the lateral rectus (LR) pulley (–3.6 ± 1.2 mm vs. − 2.0 ± 1.1 mm, p < 0.01) and temporal displacement of the superior rectus (SR) pulley (–0.4 ± 1.2 mm vs. − 1.6 ± 0.8 mm, p < 0.01). No significant differences were observed in medial rectus or inferior rectus pulley positions. Inferior LR pulley displacement correlated with inferior SR pulley displacement (r = 0.41, p = 0.03), whereas no significant relationship was observed between LR pulley position and MR or IR pulley position. Rupture of the LR–SR band was observed in 24 orbits (80.0%).<br> Conclusion: Older Japanese adults with XT exhibit localized pulley displacement and LR–SR band rupture. These structural changes differ from the global sagging observed in sagging eye syndrome and may contribute to the pathogenesis of acquired exotropia in older adults. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1574-7891 2026 Stimulator of interferon genes agonist augmented antitumor immunity of osimertinib in <i>Egfr</i> ‐mutated lung cancer EN Jun Nishimura Department of Hematology, Oncology and Respiratory Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tadahiro Kuribayashi Department of Hematology, Oncology and Respiratory Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Johannes Brägelmann Department of Translational Genomics Faculty of Medicine and University Hospital Cologne, University of Cologne Germany Sachi Okawa Department of Hematology, Oncology and Respiratory Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masataka Taoka Department of Hematology, Oncology and Respiratory Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shunta Mori Department of Hematology, Oncology and Respiratory Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tomoka Nishimura Department of Hematology, Oncology and Respiratory Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Takaaki Tanaka Department of Hematology, Oncology and Respiratory Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Go Makimoto Department of Respiratory Medicine, Okayama University Hospital Kiichiro Ninomiya Center for Comprehensive Genomic Medicine, Okayama University Hospital Kammei Rai Center for Innovative Clinical Medicine, Okayama University Hospital Eiki Ichihara Center for Clinical Oncology, Okayama University Hospital Ryohei Katayama Division of Experimental Chemotherapy, Cancer Chemotherapy Centre, Japanese Foundation for Cancer Research Katsuyuki Hotta Center for Innovative Clinical Medicine, Okayama University Hospital Masahiro Tabata Center for Clinical Oncology, Okayama University Hospital Yosuke Togashi Department of Respiratory Medicine, Okayama University Hospital Yoshinobu Maeda Department of Hematology, Oncology and Respiratory Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Martin L. Sos Department of Translational Genomics Faculty of Medicine and University Hospital Cologne, University of Cologne Germany Katsuyuki Kiura Department of Respiratory Medicine, Okayama University Hospital Kadoaki Ohashi Department of Respiratory Medicine, Okayama University Hospital Epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancers (NSCLCs) lack effective immunotherapy due to a noninflamed tumor microenvironment (TME). We previously reported that EGFR tyrosine-kinase-inhibitor (TKI) induced CD8+ T-cell immunity, which was insufficient for tumor eradication. We evaluated the potential of combining EGFR-TKI with stimulator of interferon genes (STING) agonists in activating a systemic antitumor response. Using a syngeneic mouse model of genetically engineered Egfr-mutant NSCLC, we evaluated the antitumor effects of STING agonist ADU-S100, alone and combined with osimertinib. Immunohistochemistry and flow cytometry were used to assess the TME. Osimertinib alone enhanced CD8+ T-cell infiltration but not Natural Killer (NK) cell infiltration. ADU-S100 injection alone modestly suppressed tumor growth with increasing CD8+/NK cell infiltration in the TME, but lacked an abscopal effect. Combining ADU-S100 with osimertinib significantly enhanced the antitumor effects and CD8+/NK cell infiltration. Depletion of either CD8+ or NK cells reduced the combination effect. Crucially, the combination induced an abscopal effect accompanied by PD-1+/CD8+ cell infiltration. Combining osimertinib with a STING agonist augmented innate and adaptive immunity, inducing systemic antitumor responses in EGFR-mutant NSCLC. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2041-1723 17 1 2026 Structural insights into YheS-mediated release of SecM-arrested ribosome 4963 EN Kaishi Iso Department of Biological Sciences, Graduate School of Science, The University of Tokyo Toma Ikeda School of Life Science and Technology, Institute of Science Tokyo Kohei Yamasaki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yushin Ando Department of Biological Sciences, Graduate School of Science, The University of Tokyo Fumiya K. Sano Department of Biological Sciences, Graduate School of Science, The University of Tokyo Tadaomi Furuta School of Life Science and Technology, Institute of Science Tokyo Hideki Taguchi School of Life Science and Technology, Institute of Science Tokyo Osamu Nureki Department of Biological Sciences, Graduate School of Science, The University of Tokyo Yuhei Chadani Faculty of Environmental, Life, Natural Science and Technology, Okayama University Yuzuru Itoh Department of Biological Sciences, Graduate School of Science, The University of Tokyo ATP-binding cassette subfamily F (ABCF) proteins interact with the ribosome to resolve translation defects near the peptidyl transferase center (PTC). In Escherichia coli, four ABCF proteins (EttA, Uup, YbiT, and YheS) selectively promote translation of distinct problematic nascent peptide sequences, but their molecular mechanisms remain unclear. Here, we present a 2.8 Å cryo-EM structure of the ribosome in complex with an ATPase-deficient mutant of YheS and investigate how it releases ribosomes arrested by the SecM nascent chain. YheS binds to the ribosomal E-site via the L1 stalk, and its P-site tRNA-interaction motif (PtIM) extends toward the PTC, displacing the CCA end of the P-site tRNA. Notably, the cryo-EM density corresponding to the SecM nascent chain within the exit tunnel is largely lost upon YheS binding. These observations suggest that YheS relieves peptide sequence-dependent stalling by perturbing nascent chain-tunnel interactions through P-site tRNA relocation. Steered molecular dynamics simulations provide qualitative support for this model. Together, our findings provide mechanistic insight into a mode of arrest release distinct from the translocon-mediated release mechanism. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1755-4330 18 6 2026 Two-dimensional metal–organic frameworks offer all-in-one cocatalysts for photocatalytic overall water splitting 1053 1061 EN Jingyan Guan Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University Hajime Suzuki Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University Kazuhide Kamiya Research Center for Solar Energy Chemistry, Graduate School of Engineering Science, The University of Osaka Takashi Harada Research Center for Solar Energy Chemistry, Graduate School of Engineering Science, The University of Osaka Rintaro Adachi Graduate School of Natural Science and Technology, Okayama University Osamu Tomita Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University Hirofumi Kurokawa Institute of Multidisciplinary Research for Advanced Materials, Tohoku University Daisuke Unabara Institute of Multidisciplinary Research for Advanced Materials, Tohoku University Koji Yonekura Institute of Multidisciplinary Research for Advanced Materials, Tohoku University Naoya Fukui Research Institute for Science and Technology, Tokyo University of Science Hiroaki Maeda Research Institute for Science and Technology, Tokyo University of Science Kunihisa Sugimoto Department of Chemistry, Kindai University Yuichi Yamaguchi Department of Applied Chemistry, Faculty of Science, Tokyo University of Science Akinori Saeki Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives, The University of Osaka Akira Yamakata Graduate School of Natural Science and Technology, Okayama University Akihiko Kudo Department of Applied Chemistry, Faculty of Science, Tokyo University of Science Ryu Abe Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University Ryota Sakamoto Department of Chemistry, Graduate School of Science, Tohoku University Photocatalytic overall water splitting holds great promise for sustainable hydrogen production. For overall water splitting performed by one-step excitation, both the hydrogen evolution and oxygen evolution reactions are hindered kinetically; hence, it is necessary to employ site-selective modification of photocatalysts with hydrogen-evolving and oxygen-evolving cocatalysts. However, critical challenges remain, including the need for cumbersome, multi-step photodeposition processes and durable blocking layers to inhibit the reverse reactions. Here we find a conductive, two-dimensional metal–organic framework to serve as a simple, multifunctional cocatalyst. We loaded this framework on SrTiO3:Al, an overall water-splitting photocatalyst, using a one-step self-assembly method. The framework cocatalyst promoted steady photocatalysis with an apparent quantum efficiency of 31.5% at 350 nm, free from the reverse reaction even without blocking layers. We proposed the operational principles for the cocatalyst activity using spectroscopic, electrochemical and theoretical analyses. This two-dimensional metal–organic framework offers an all-in-one approach for designing efficient and practical one-step excitation overall water-splitting systems. No potential conflict of interest relevant to this article was reported.

Public Library of Science (PLoS) Acta Medica Okayama 1553-7404 22 2 2026 Octopamine signaling from clock neurons plays dual roles in Drosophila long-term memory e1012045 EN Yuto Kurata Department of Biological Sciences, Tokyo Metropolitan University Taishi Yoshii Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takaomi Sakai Department of Biological Sciences, Tokyo Metropolitan University Circadian clock genes are best known for regulating circadian rhythms, but they also play crucial roles in memory processes. This suggests that memory is modulated by neural networks containing clock neurons, although the underlying mechanisms remain unclear. In Drosophila melanogaster, approximately 240 clock neurons are grouped into at least eight distinct clusters. Among them, the dorsal–lateral neurons (LNds) are required for maintaining long-term memory (LTM). In contrast, the neuropeptide Pigment-dispersing factor (Pdf), expressed in both small and large ventral–lateral neurons (s-LNvs and l-LNvs, respectively), functions as a circadian output signal and is also essential for maintaining LTM. In addition, Pdf-expressing neurons (hereafter, Pdf neurons) release neurotransmitters other than Pdf, which are involved in LTM consolidation. However, the specific transmitters used by LNds and Pdf neurons in LTM processing have remained unknown. Here, we show that octopamine signaling from LNds is essential for LTM maintenance, whereas octopamine in Pdf neurons is essential for LTM consolidation. Temporally restricted knockdown of Tyramine β hydroxylase (Tbh), the gene encoding the enzyme required for octopamine synthesis, disrupted LTM maintenance when targeted in LNds, whereas it impaired LTM consolidation when targeted in Pdf neurons. Notably, Tbh knockdown in LNds or Pdf neurons had minimal effects on circadian behavioral rhythms or sleep. These findings reveal that octopamine released from specific subtypes of clock neurons independently regulates distinct phases of LTM in Drosophila. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 1422-0067 27 11 2026 Genomic Basis of Lifestyle Divergence in Rice-Associated Burkholderia: From Pathogenesis to Plant Growth Promotion 4730 EN Andrews Danso Ofori State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University Zohreh Nasimi State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University Frank Kwekucher Ackah Department of Crop Science, School of Agriculture and Natural Sciences, University of Cape Coast Muhammad Irfan Ahmed State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University Yaoting Yan State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University Wang Li State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University Abdul Ghani Kandro State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University Kazunori Okada Agro-Biotechnology Research Center, The University of Tokyo Keiichi Mochida Bioproductivity Informatics Research Team, RIKEN Center for Sustainable Resource Science Yoshiteru Noutoshi Graduate School of Environmental and Life Science, Okayama University Aiping Zheng State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University The genus Burkholderia encompasses both plant pathogenic and beneficial species, yet the genomic determinants underlying this lifestyle divergence remain poorly understood. Using 16S rRNA sequencing of 100 rice cultivars, our companion study demonstrated that resistant varieties are enriched in beneficial Burkholderiaceae, leading to the isolation of three phenotypically contrasting strains. Here, we present comparative genomic analyses of non-pathogenic biocontrol strain Burkholderia vietnamiensis J14EpLeaf2 and pathogenic strains Burkholderia gladioli A1EpSeed5 and Burkholderia cepacia J14Eple. Pathogenic strains possess significantly larger genomes (8.36–8.46 Mb) enriched in mobile genetic elements compared to the streamlined 6.95 Mb genome of B. vietnamiensis. CAZyme analysis revealed broader repertoires of glycoside hydrolases and polysaccharide lyases in pathogens, consistent with enhanced plant cell wall degradation. B. gladioli possesses a complete T3SS and expanded T6SS with 301 predicted effectors, while B. cepacia lacks structural T3SS genes but harbors 271 candidate effectors predicted to be secreted via alternative secretion pathways, compared to 180 in B. vietnamiensis. Notably, B. cepacia harbors cystic fibrosis-associated markers (cable pili, ZmpA/ZmpB), raising significant biosafety concerns that preclude its agricultural application. LC-MS validated IAA, ornibactin, and AHL production in B. vietnamiensis, supporting its plant growth-promoting and biocontrol functions. Computational PPI networks predicted distinct interaction landscapes requiring experimental validation. This study provides a genomic framework for distinguishing pathogenic from beneficial Burkholderia and supports B. vietnamiensis as a safe biocontrol agent while cautioning against B. cepacia J14Eple. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0012-1592 68 4-5 2026 Computer‐Aided Sperm Analysis Protocol for Evaluating Sperm Motility in Japanese Medaka e70061 EN Miwa Kuroyanagi Department of Advanced Aquaculture Science, Faculty of Marine Bioscience and Technology, Fukui Prefectural University Satoshi Ansai Ushimado Marine Institute, Faculty of Science, Okayama University Keigo Okamoto Laboratory of Aquatic Molecular Developmental Biology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University Ai Kato Interuniversity Bio-Backup Project Center, National Institute for Basic Biology (NIBB) Touko Yamazaki Laboratory of Bioresources, National Institutes of Natural Sciences Yasuhiro Kamei Optics and Bioimaging Facility, NIBB Eiji Watanabe Basic Biology Program, Graduate University for Advanced Studies (SOKENDAI) Kiyoshi Naruse Laboratory of Bioresources, National Institutes of Natural Sciences Yukiko Ogino Laboratory of Aquatic Molecular Developmental Biology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University Changes in sperm motility can serve as an early indicator of reproductive effects caused by environmental chemicals or genetic perturbations. However, sperm motility is highly sensitive to external factors such as osmolarity, ionic composition, and the timing of measurement after activation, making it challenging to obtain consistent and reproducible measurements. Here, we present a standardized protocol for assessing sperm motility in Japanese medaka (Oryzias latipes) using a sperm motility analysis system (SMAS), an application for computer-aided sperm motility analysis (CASA). This protocol details the procedures for sperm collection, activation, and quantitative motility assessment, with particular focus on changes in the percentage of motile sperm post activation and the effects of sperm cryopreservation. We demonstrate time-dependent declines in sperm motility and velocity, and highlight the importance of early post-activation measurements to accurately capture peak motility. Notably, cryopreservation significantly accelerated the decline in sperm motility rate without affecting the initial proportion of motile sperm. To enable reliable comparisons among experimental groups, we recommend standardizing the initiation time after sperm activation by using CASA, and show that measurements should be initiated within 1 min after activation to obtain consistent and reliable data. This standardized SMAS-based protocol provides a robust and reproducible framework for sperm motility analysis in medaka and will be valuable not only for studies in reproductive biology, toxicology, and environmental risk assessment but also for applied research, such as breeding of aquacultural fishes. No potential conflict of interest relevant to this article was reported.

Portland Press Ltd. Acta Medica Okayama 0144-8463 46 6 2026 Tubulogenesis of bovine uterine glands by epidermal growth factor and collagen I in 3D culture systems BSR20260010 EN Yosuke Sugino Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Rei Ichikawa Graduate School of Bioagricultural Sciences, Nagoya University Shuichi Matsuyama Graduate School of Bioagricultural Sciences, Nagoya University Yuki Yamamoto Department of Veterinary Medicine, Tokyo University of Agriculture and Technology Kohei Kawano Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Koji Kimura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Uterine glands are endometrial exocrine epithelia that support early embryo development. Their secretions are particularly essential for conceptus elongation in cattle. Uterine glands develop from the luminal epithelium and elongate into the stromal layer toward the myometrium. This process is regulated by growth factors, WNT proteins, and the surrounding extracellular matrix (ECM); however, the precise mechanisms that govern bovine uterine gland morphogenesis remain unclear. In this study, we determined how these signaling factors and ECM components affect the tubular formation of bovine uterine gland fragments in 3D culture systems. Uterine gland fragments were enzymatically isolated from bovine endometria and 3D-cultured in Matrigel with or without growth factors (EGF, FGF1, FGF2, FGF7, FGF10, and IGF-1) and WNT (WNT3A, WNT5A, and WNT7A) proteins. Of these, only EGF stimulated the elongation of uterine gland fragments and eventually induced the formation of uterine gland-like structures. EGF-induced tubulogenesis was accompanied by a rapid increase in cell proliferation and alterations in cell–ECM interactions. The supplementation of collagen I with Matrigel further promoted the elongation of the tubular structures. Although the addition of collagen I did not alter the gene expression profiles of the uterine gland-like structures, the integrin-ROCK pathway contributed to the collagen-induced enhancement of elongation. Our findings clarified that EGF and collagen I, but not FGFs, IGF-1, or WNTs, are key regulators for the tubular formation of 3D-cultured bovine uterine gland fragments. This 3D culture system provides a new platform to examine the cellular and molecular mechanisms underlying bovine uterine gland morphogenesis. No potential conflict of interest relevant to this article was reported.

Institute of Electrical and Electronics Engineers (IEEE) Acta Medica Okayama 2169-3536 14 2026 Construction of a Lightweight Simulation Environment Based on Topological Mapping 73466 73478 EN Yukinaga Kato Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Yuichiro Toda Faculty of Environmental, Life, Natural Science, and Technology, Okayama University Takayuki Matsuno Faculty of Environmental, Life, Natural Science, and Technology, Okayama University Autonomous mobile robots require safe and efficient environmental representations for traversability-aware navigation and learning. In particular, self-learning of traversability from real-world driving experience can require robots to operate near the limits of their mobility, which introduces physical risks such as falls, malfunctions, or hardware damage. To provide a safer complementary environment for such validation and future learning, this paper proposes ATC-Mesh. This framework constructs a lightweight, simulation-ready mesh environment from the topological map produced by Adaptive Resonance Theory-based Topological Clustering with Different Topologies (ATC-DT) using high-density LiDAR point clouds. Unlike standard mesh reconstruction methods that directly process dense point clouds, ATC-Mesh generates a compact mesh from the node–edge structure of the topological map while preserving traversability attributes associated with the topological map. Experiments using two real-world LiDAR datasets show that ATC-Mesh achieves competitive mesh-construction quality compared with standard baseline methods while reducing construction time and mesh size. Gazebo experiments further show that the generated meshes can support waypoint-based navigation with a low simulation load. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0753-3322 194 2026 Elucidation of mechanisms underlying the therapeutic effects of cordycepin on pulmonary hypertension, with a focus on cell senescence and gut microbiota 118923 EN Gaopeng Li Department of Cardiovascular Physiology, Faculty of Medicine, Kagawa University Zhixin Zhao Inner 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 University Mitsuhiro Machitani Division of Cancer Stem Cell, National Cancer Center Research Institute Ryou Ishikawa Department of Diagnostic Pathology, Kagawa University Hospital Kaori Ishikawa Department of General Medicine, Kagawa University Hospital Naoya Yokota Department of General Thoracic Surgery, Faculty of Medicine, Kagawa University Reiji Haba Department of Diagnostic Pathology, Kagawa University Hospital Kazufumi Nakamura Center for Advanced Heart Failure, Okayama University Hospital Zhihong Sun Inner 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 University Lin-Hai Kurahara Department of Cardiovascular Physiology, Faculty of Medicine, Kagawa University Katsuya Hirano Department of Cardiovascular Physiology, Faculty of Medicine, Kagawa University Introduction: 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.

Elsevier BV Acta Medica Okayama 0040-4039 183 2026 Photochemical oxidative synthesis of carboxylic acids from aldehydes or alcohols with water via CH bromination 156163 EN Mohamed R. El-kholany Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Atsuya Miyamoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Morgane Falcone Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hiroyoshi Takamura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Isao Kadota Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kenta Tanaka Graduate School of Environmental, Life, Natural Science and Technology, Okayama University The photoinduced oxidation of aldehydes or alcohols with water to give the corresponding carboxylic acids is described. This photochemical carboxylation proceeds via the in-situ generation of acyl-bromide intermediates upon irradiation with purple or UV LED light; these intermediates subsequently react with water to give the desired carboxylic acids. This mild photochemical reaction affords diverse carboxylic acids without peroxide generation or the need to use transition-metal catalysts and a stoichiometric amount of base, highlighting its potential utility for the synthesis of natural products and bioactive compounds. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-7345 2026 Switchable photoluminescence of europium(iii) complexes with chromonylhydrazones EN Asahi Kamei Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Daisuke Saito Graduate School of Science, Hokkaido University Kazuma Takahara Graduate School of Science, University of Hyogo Keito Nose Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hideki Okamoto Department of Chemistry, Faculty of Environmental, Life, Natural Science and Technology, Okayama University Masaki Yoshida Graduate School of Science, The University of Osaka Masako Kato School of Biological and Environmental Sciences, Kwansei Gakuin University Takayoshi Suzuki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Europium(III) complexes bearing 4-hydroxy- or 4-methyl-N′-((6-methyl-4-oxo-4H-chromen-3-yl)methylene)benzohydrazide (HL1 or HL2) showed characteristic EuIII 5D0 → 7FJ (J = 0–4) luminescence both in acetonitrile and in solid states with relatively high Φtot values. The luminescence was quenched not only by adding triethylamine in acetonitrile, but also by heating the solid sample, and recovered by adding perchloric acid in solution or by diffusion of HCl vapor to the resulting solid sample. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0916-7005 43 2 2026 Machine learning prediction of the Madden–Julian oscillation using reservoir computing 25 EN Tamaki Suematsu RIKEN Center for Computational Science Kengo Nakai Graduate School of Environmental Life, Natural Science and Technology, Okayama University Tsuyoshi Yoneda Graduate School of Economics, Hitotsubashi University Daisuke Takasuka Department of Geophysics, Tohoku University Takuya Jinno Graduate School of Science, The University of Tokyo Yoshitaka Saiki Graduate School of Business Administration, Hitotsubashi University Hiroaki Miura Graduate School of Science, The University of Tokyo The prediction of the Madden–Julian Oscillation (MJO), a massive tropical weather event with global socio-economic impacts, has been infamously difficult with physics-based weather prediction models. We employ the reservoir computing, a brain-inspired machine-learning technique, to construct a machine learning model that forecasts the real-time multivariate MJO index (RMM), a macroscopic variable that represents the state of the MJO. The training data was refined by development of a novel real-time band-pass filter that extracts the recurrency of MJO signals only from the past raw atmospheric data, and by selection of a suitable time-delay coordinate of the RMM that enhances the recurrency of the input data. The constructed model demonstrated the skill to forecast the time sequence of the RMM for a month from pre-developmental stages of the MJO. Examination of best-performing cases suggested that RMM sequences may be predicted for over two months in some cases. These results imply that inherent predictability limit of the MJO is longer than that has been estimated from physics-based weather prediction models. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1759-9954 17 23 2026 Synthesis of a BC6 polymer via cyclotrimerization of alkynylborane and its application as a heterogeneous Lewis acid catalyst 2473 2478 EN Naoki Takahashi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kentaro Ohkura Research Institute for Interdisciplinary Science, Okayama University Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Lewis acidic boron-containing π-conjugated polymer materials have been demonstrated to be promising for sensing and catalysis; however, the synthetic approaches and the number of installed boron atoms have been limited. Herein, we report the synthesis of a BC6 polymer structure via cyclotrimerization of alkynes. The resulting polymer exhibited superior catalytic activity to small-molecule analogues such as BPh3 and previously reported boron-containing polymers. This enhanced performance is attributed to the high boron content and increased Lewis acidity of BC6, as supported by theoretical and experimental analyses. Owing to its polymeric nature, the catalyst was readily recovered and reused in the catalytic system. These findings demonstrate that building rigid polymer frameworks with a high density of Lewis acidic boron sites is a promising approach to developing recyclable heterogeneous Lewis acid catalysts, and offers a broadly applicable design principle for functional boron-containing polymeric materials. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1867-1071 2026 A novel robot for CT-guided bone needle insertion with a rotational drilling and force-feedback speed control mechanism: preliminary evaluation in swine EN Yusuke Matsui Department of Radiology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takao Hiraki Department of Radiology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuta Kimura Department of Radiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takanori Sasaki Collaborative Research Center for OMIC, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Ryutaro Matsuura Department of Radiological Technology, Faculty of Health Sciences, Okayama University Koji Tomita Department of Radiology, Medical Development Field, Okayama University Noriyuki Umakoshi Department of Radiology, Medical Development Field, Okayama University Soichiro Okamoto Department of Radiology, Medical Development Field, Okayama University Kazuaki Munetomo Department of Radiology, Medical Development Field, Okayama University Fumiyo Higaki Department of Radiology, Medical Development Field, Okayama University Jun Sakurai Center for Innovative Clinical Medicine, Okayama University Hospital Toshihiro Iguchi Department of Radiological Technology, Faculty of Health Sciences, Okayama University Atsushi Nakazawa Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kiyoshi Matsumiya Department of Medical Technology, Faculty of Life Science, Okayama University of Science Takayuki Matsuno Faculty of Environmental, Life, Natural Science and Technology, Okayama University Tetsushi Kamegawa Faculty of Environmental, Life, Natural Science and Technology, Okayama University Purpose 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.

MDPI AG Acta Medica Okayama 1422-0067 27 6 2026 Minimal Association Between Immunoglobulin A Coating and Gut Microbiota Alterations Induced by High-Fat Diets with Distinct Fatty Acid Compositions 2645 EN Mao Teraoka Faculty of Environmental, Life, Natural Science and Technology, Okayama University Naoki Nishino Faculty of Environmental, Life, Natural Science and Technology, Okayama University Tianyang Wang Faculty of Environmental, Life, Natural Science and Technology, Okayama University Kuiyi Chen Faculty of Environmental, Life, Natural Science and Technology, Okayama University Takeshi Tsuruta Faculty of Environmental, Life, Natural Science and Technology, Okayama University High-fat diets (HFDs) containing dietary fats with different fatty acid (FA) compositions alter gut microbiota composition in a fat-source-dependent manner. Immunoglobulin A (IgA) and unabsorbed lipids in the distal gut are potential regulators of the gut microbiota. However, their roles in mediating gut microbiota alterations induced by dietary fats with different FA compositions remain unclear. This study aims to examine the associations of these two factors with fat-source-dependent gut microbiota alterations. BALB/c mice were fed a normal diet, a high-lard diet, a high-olive oil diet, or a high-soybean oil diet for 27 weeks. Fecal samples were collected to assess microbiota composition, the IgA coating index (ICI)—which quantifies the extent of IgA coating on gut microbiota—and fecal fatty acid concentrations. At the phylum level, the concentration of fecal total long-chain fatty acids (LCFAs) was positively correlated with the relative abundance (RA) of Bacillota and negatively correlated with that of Bacteroidota. In addition, a trend toward a positive association between the RA and the ICI was observed for Bacillota but not for Bacteroidota. At the genus level, the RAs of 12 taxa were positively correlated with fecal LCFA concentrations, whereas those of 6 taxa were negatively correlated. Although the RAs of most taxa appeared to be influenced by unabsorbed lipids and additional factors, only four Bacillota genera exhibited a positive correlation between the RA and the ICI. Our observations suggest that IgA coating of the gut microbiota may have a minimal association with fat-source-specific alterations in gut microbiota composition during HFD intake. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2352-4928 51 2026 Optical spectroscopic evaluation on the acquisition of optimal sonication temperature for efficient liquid phase exfoliation of molybdenum disulfide 114910 EN Fatimah Az-Zahra Saravanan binti Abdullah School of Engineering and Physical Sciences, Heriot-Watt University Malaysia Wengnam Lee Foundation Center, Heriot-Watt University Malaysia Patrik Öhberg Institute of Photonics and Quantum Sciences, School of Engineering and Physical Sciences, Heriot-Watt University Boontong Goh Low Dimensional Materials Research Center, Department of Physics, Faculty of Science, University of Malaya Wuyi Chong Photonics Research Center, University of Malaya Harith Ahmad Photonics Research Center, University of Malaya Yasuhiko Hayashi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takeshi Nishikawa Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuenkiat Yap Foundation Center, Heriot-Watt University Malaysia This work investigates how the sonication temperature affects the liquid phase exfoliation of MoS₂ using optical and morphological approach in attempt to acquire an optimal temperature for such process at ambient room conditions. In an ultrasonic bath, exfoliation was carried out at six different temperatures. UV-Vis, FTIR, Raman spectroscopy and SEM characterizations reveal that moderate room temperature range yield excellent results producing well-dispersed flakes with strong excitonic properties with mild oxidation. Higher temperatures cause substantial oxidation, deterioration and restacking while lower temperatures led to insufficient exfoliation and fragmented morphologies because of insufficient cavitation energy. The findings highlight the importance of temperature control in producing high quality nanosheets for scalable applications. No potential conflict of interest relevant to this article was reported.

Oxford University Press (OUP) Acta Medica Okayama 0009-2673 99 6 2026 Synthesis of boranils by iodide-mediated demethylative borylation and their properties uoag070 EN Koichi Mitsudo Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Ryo Magata Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Eisuke Sato Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tomoya Nakamura Institute for Chemical Research, Kyoto University Atsushi Wakamiya Institute for Chemical Research, Kyoto University Seiji Suga Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Boranils, difluoroboron complexes with imine and phenoxy moieties, were synthesized by iodide-promoted demethylative borylation. The use of appropriate amounts of BF3•OEt2, Bu4NI, and Et3N enabled the highly efficient synthesis of boranils. Boranils containing heteroaromatics and highly π-extended boranils were also readily obtained by this method. Their physical properties were studied, and the properties were consistent with those calculated by DFT calculations. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2730-7182 26 1 2026 Revised taxonomy reveals sustained introgression and secondary contact in ancient lake ricefishes 46 EN Yuki Yashima Tropical Biosphere Research Center, University of the Ryukyus Andy B. Nofrianto Tropical Biosphere Research Center, University of the Ryukyus Handung Nuryadi Tropical Biosphere Research Center, University of the Ryukyus Ryo Kakioka Department of Applied Aquabiology, National Fisheries University Hirozumi Kobayashi The Natural History Museum and Institute Satoshi Ansai Ushimado Marine Institute, Okayama University Ixchel F. Mandagi Faculty of Fisheries and Marine Science, Sam Ratulangi University Kawilarang W. A. Masengi Faculty of Fisheries and Marine Science, Sam Ratulangi University Sjamsu A. Lawelle Faculty of Fisheries and Marine Science, Halu Oleo University Atsushi J. Nagano Bioscience and Biotechnology Center, Nagoya University Junko Kusumi Faculty of Social and Cultural Studies, Kyushu University Kazunori Yamahira Tropical Biosphere Research Center, University of the Ryukyus Background Biotic diversification in ancient lakes is shaped by complex geological histories and genetic exchange among populations. The Malili Lake system on Sulawesi Island represents a classic natural laboratory for studying freshwater fish evolution and harbors multiple endemic Oryzias species that diversified under repeated hydrological reorganizations. Previous genomic analyses inferred that two sympatric species in Lake Towuti (O. profundicola and O. loxolepis) experienced a single ancient introgression event from a “ghost lineage” derived from O. marmoratus inhabiting another lake. However, recent taxonomic re-evaluation has revealed the presence of an extant O. marmoratus population within Lake Towuti itself. This finding suggests that the putative ghost lineage may in fact represent a living population co-occurring in the lake, calling for a re-examination of the introgression history and speciation mode in Lake Towuti.<br> Results By incorporating newly generated ddRAD-seq data from the true O. marmoratus in Lake Towuti, we reanalyzed phylogenetic relationships and population genetic structure among Malili Lake Oryzias. Previously reported major phylogenetic relationships and inter-lake introgression patterns were largely reproduced. In contrast, TreeMix and f4-statistic analyses revealed that introgression signals previously attributed to a “ghost lineage” into O. profundicola and O. loxolepis instead originated from the extant O. marmoratus population coexisting within Lake Towuti. Demographic model comparisons explicitly incorporating within-lake gene flow further supported a scenario in which O. profundicola and O. loxolepis diverged in allopatry, subsequently came into secondary contact within Lake Towuti, and later experienced additional gene flow following secondary contact with O. marmoratus that entered the lake.<br> Conclusion Our results demonstrate that introgression from the O. marmoratus lineage into O. profundicola and O. loxolepis was not a single ancient event, but rather a more sustained process. This finding highlights the critical importance of taxonomic resolution for accurately inferring introgression and divergence history. Comparative studies across other ancient lakes on Sulawesi will be valuable for understanding how the timing and nature of gene flow from third lineages influence patterns of population divergence and the strength of reproductive isolation. No potential conflict of interest relevant to this article was reported.

岡山大学文明動態学研究所文化遺産マネジメント部門 Acta Medica Okayama 2758-9625 2024 2026 岡山大学文明動態学研究所文化遺産マネジメント部門紀要2024 EN No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1615-4150 368 12 2026 Synthesis of Aromatic Aldehydes by C─H Formylation of Aromatics with Silyl Formates Prepared from CO2 and Hydrosilanes e70571 EN Natsumi Nitta Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kei Hirokawa Graduate School of Environmental, Life, Natural Science and Technology, Okayama University So Saibara Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Bikash Dev Nath Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kazuto Takaishi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tadashi Ema Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Despite the recent remarkable progress in CO2 fixation reactions, the methods for the synthesis of aldehydes from CO2 are quite limited partly because of the lability of the resulting formyl group and difficulty in the controlled deoxygenative CO2 conversions leading to C─H and C─C bond formation. Here, we have developed the direct C─H formylation of electron-rich aromatics using silyl formates, prepared from CO2 and hydrosilanes, in the presence of BCl3 or BBr3. This is the first report on the direct C─H formylation of aromatics with silyl formates. Useful compounds including a biologically active compound and octaethylporphyrin were synthesized by fixing one to four CO2 molecules in a stepwise manner. DFT calculations have been done to elucidate the reaction mechanism including a dual role of BBr3 in the activation of silyl formate, HCO2SiMe2Ph, and electrophilic aromatic substitution. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2227-7390 14 12 2026 Toward Convergence in Multi-Agent Reinforcement Learning: Best-Response Space Shrinking as a Sufficient Condition 2134 EN Natchanon Manatphaiboon Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Akito Monden Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Zeynep Yücel Department of Environmental Sciences, Informatics and Statistics, Ca’Foscari University of Venice We study convergence in multi-agent reinforcement learning (MARL) through the lens of sufficient conditions, using a single-point-of-failure analysis applied to multi-agent policy iteration integrated with linear programming (MAPI-LP), where results are proven for pure coordination games, and extension to broader settings is conjectured. We identify two sufficient conditions for convergence to Markov Perfect Equilibrium (MPE). The first is stability in best-response space that emerges from value monotonicity. The second, monotonic best-response space shrinking (MBRSS), is a novel condition requiring that each agent’s best-response space contracts monotonically across iterations until it collapses to a stable space. Furthermore, we show that MBRSS does not necessarily imply monotonic improvement in this setting. However, value monotonicity and stability in best-response space imply each other when a complementary condition is applied. Building on this hierarchical relationship, we propose conjectures on sufficient condition relationships in both serial and parallel MARL. In addition, we propose conjectures on generalized MBRSS to arbitrary finite repeated games and validation of stability in best-response space. We further discuss connections between MBRSS and existing related frameworks, and outline directions toward a taxonomy of sufficient conditions for MARL convergence. No potential conflict of interest relevant to this article was reported.

The Company of Biologists Acta Medica Okayama 0022-0949 229 2 2026 Insulin-like peptide has antagonistic pleiotropic effects on male combat traits and survival traits in an armed beetle jeb251318 EN Takumi Kato Graduate School of Science, Nagoya University Chiho Yoshimine Graduate School of Science, Tokyo Metropolitan University Haruna Fujioka Graduate School of Environmental, Natural Science and Technology, Okayama University Masako Katsuki Graduate School of Science, Nagoya University Kensuke Okada Graduate School of Environmental, Natural Science and Technology, Okayama University Yasukazu Okada Graduate School of Science, Nagoya University The expression of sexually selected traits, such as exaggerated weapons and ornaments, often entails trade-offs against life-history traits. While phenotypic trade-offs are well documented, the underlying molecular physiological mechanisms remain largely unexplored. In this study, we investigated the potential role of an insulin-like peptide, ILP2, in mediating the trade-off between sexually selected combat traits and survival traits in the broad-horned flour beetle, Gnatocerus cornutus. RNA interference (RNAi)-mediated knockdown (KD) of ILP2 during larval stages resulted in a reduction in the development of mandibular horns and overall body size. Interestingly, ILP2 KD males had increased lipid storage and enhanced starvation tolerance, indicating a shift in resource allocation from sexually selected traits to survival traits. Behaviorally, ILP2 KD males showed decreased locomotor activity and reduced aggression, leading to lower combat success. These findings suggest that ILP2 functions as a key mediator in the allocation of resources between combat and survival traits, highlighting its pleiotropic effects on morphology, metabolism and behavior. Our study provides novel insights into the molecular physiological mechanisms underlying life-history trade-offs associated with sexually selected traits. No potential conflict of interest relevant to this article was reported.

Frontiers Media SA Acta Medica Okayama 2673-253X 8 2026 Development of a generative AI agent for family support in implementing family-based treatment for children and adolescents with anorexia nervosa 1759690 EN Mana Hanzawa Department of Pediatrics, Okayama University Hospital Medical Center for Children Joe Hasei Department of Medical Informatics and Clinical Support Technology Development, Faculty of Medicine, Dentistry and Pharmaceutical Sciences Ayumi Okada Department of Pediatrics, Okayama University Hospital Medical Center for Children Chie Tanaka Department of Pediatrics, Okayama University Hospital Medical Center for Children Yoshie Shigeyasu Department of Pediatrics, Okayama University Hospital Medical Center for Children Chikako Fujii Department of Pediatrics, Okayama University Hospital Medical Center for Children Makiko Horiuchi Clinical Psychology Section, Department of Medical Support, Okayama University Hospital Akiko Sugihara Department of Pediatrics, Okayama University Hospital Medical Center for Children Koichi Takeuchi Life Natural Science and Technology, Graduate School of Environmental, Okayama University Ryuichi Nakahara Department of Musculoskeletal Health Promotion, Faculty of Medicine, Dentistry and Pharmaceutical Sciences Hideki Katayama Department of Palliative and Supportive Care, Okayama University Hospital Yasushi Takahashi NEC Corporation Toshifumi Ozaki Department of Orthopaedic Surgery, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hirokazu Tsukahara Department of Pediatrics, Okayama University Hospital Medical Center for Children Introduction: Family-based treatment (FBT) is a first-line psychotherapy for children and adolescents with anorexia nervosa (AN). However, families must understand the principles of FBT, provide meal support, and manage their children's pathological behaviors. Difficulties occur outside clinic hours when it is impossible to consult professionals. This “support gap” increases caregivers’ psychological distress and threatens their treatment continuity. To the best of our knowledge, this is the first domain-specific generative artificial intelligence (AI) agent designed to provide situation-specific, FBT-concordant advice and psychological support.<br> Methods: The system integrates three components: (1) an FBT-specific knowledge base constructed from treatment manuals, family guides, guideline-compliant resources, and a clinical Q&A corpus; (2) a multistage natural language processing pipeline using Retrieval-Augmented Generation (RAG), with intent and sentiment analyses; and (3) safety guardrails that prohibit unsolicited numerical goals or direct hospitalization recommendations and standardized escalation to clinicians. When strong negative emotions are detected, empowerment messages are dynamically incorporated to maintain caregivers’ confidence. Six clinicians with expertise with pediatric mental health authored queries that simulated common FBT-related concerns and evaluated each response for clinical appropriateness and safety, and classified problems as information insufficiency, not FBT concordant, or escalation insufficiency.<br> Results: Of the 477 queries, 57.0% were FBT-related, 24.5% were general AN, 16.5% were parental psychological distress, and 1.8% were related to other topics. The clinically appropriate response rate was 91.6% (437/477), including 92.3% for FBT-related questions, 88.0% for general knowledge, 93.7% for psychological distress, and 100.0% for other questions. Clinically inappropriate responses (8.4%) were mainly attributable to information insufficiency; not FBT concordant (1.8% of FBT-related responses) and escalation insufficiency (0.6% of all dialogs) rarely occurred.<br> Discussion: In this expert review, the safety-gated RAG system predominantly generated FBT-concordant responses that provided meal-level guidance and empathic empowerment-oriented support to families. By proceduralizing complex FBT concepts and presenting multiple response options for pathological behaviors, the system translates FBT principles into practical guidance supporting refeeding adherence, preserving family self-efficacy, and suggesting that domain-specific AI may help bridge structural limitations in FBT. Usability studies and randomized controlled trials are warranted to determine their impact on caregiver burden, self-efficacy, treatment adherence, and clinical outcomes. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1477-9226 2026 Unraveling the structural features of Dion–Jacobson-type layered perovskite-related material HCa2Nb3O10·1.5H2O EN Zihao Zhang Faculty of Environmental, Life, Natural Science and Technology, Okayama University Jun Kano Faculty of Environmental, Life, Natural Science and Technology, Okayama University Shu Morita Institute of Materials and Systems for Sustainability (IMaSS), Nagoya University Hiromu Shimokawa Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Minoru Osada Department of Materials Chemistry and Institute of Materials and Systems for Sustainability (IMaSS), Nagoya University Hydrated layered oxides are widely encountered, yet the presence of disordered interlayer water often complicates crystal structure determination from laboratory X-ray diffraction. Here, we report the crystal structure of the Dion–Jacobson-type layered perovskite-related material HCa2Nb3O10·1.5H2O, solved from synchrotron X-ray diffraction data by combining direct methods in reciprocal space, Le Bail whole-pattern fitting, and Rietveld refinement. The hydrate crystallizes in a tetragonal structure with space group P42212 (a = 7.7070(5) Å, c = 32.4870(3) Å). Incorporation of partially occupied interlayer water-oxygen sites on the (110) plane at z = 0 and 1/2 successfully reproduces the low-angle 00l reflections while preserving the Ca2Nb3O10 framework. The resulting crystallographic model explicitly resolves the arrangement of interlayer water molecules and provides a robust structural foundation for band-structure calculations as well as for the rational design of hydration-controlled intercalation, exfoliation, and composite materials based on layered perovskite-related materials. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2666-951X 19 2026 Heteroarylation of mono- and dichloroarenes via phenothiazine organophotoredox catalysis 100163 EN Masato Oishi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hiroyoshi Takamura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Isao Kadota Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kenta Tanaka Graduate School of Environmental, Life, Natural Science and Technology, Okayama University 2-Arylpyrroles are key structural motifs found in a wide range of pharmaceuticals and functional materials. Although the photocatalytic heteroarylation of pyrroles with aryl iodides and bromides has been extensively developed for the synthesis of 2-arylpyrroles, the corresponding reactions using aryl chlorides remain relatively unexplored owing to the high energy barrier associated with C(sp2)–Cl bond activation. Herein, we report a phenothiazine-based organophotoredox-catalyzed heteroarylation of aryl chlorides with pyrroles for the synthesis of diverse 2-arylpyrroles. Notably, dichloroarenes also efficiently undergo heteroarylation to afford the corresponding products. Therefore, the present reaction represents a versatile approach to heteroarylation and provides a valuable tool for the synthesis of pharmaceuticals and functional materials. No potential conflict of interest relevant to this article was reported.

Oxford University Press (OUP) Acta Medica Okayama 0032-0781 2026 Involvement of tRNA thiolation in uORF-mediated translational regulation during Xylogenesis in Arabidopsis thaliana pcag055 EN Yuichi Nishii Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Daichi Araki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Mitsuru Saraumi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Taku Takahashi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Post-transcriptional modification of tRNAs is an important mechanism for regulating translation efficiency and cellular homeostasis, yet its contribution to upstream open reading frame (uORF)-mediated translational control remains largely unexplored. In this study, we investigated the role of tRNA thiolation in thermospermine-dependent regulation of xylem development in Arabidopsis thaliana. Using a suppressor screen of the thermospermine-deficient mutant acaulis5 (acl5), which exhibits dwarfism and excessive xylem differentiation, we identified suppressor-of-acl502 (sac502) as a recessive loss-of-function allele of CTU2, a gene encoding a key enzyme in the biosynthesis of the wobble uridine modification 5-methoxycarbonylmethyl-2-thiouridine. Mutations in other components of the same modification pathway, including ROL5 and TRM9, similarly suppressed the acl5 phenotype. Translational analyses using 5′ leader-GUS reporter constructs revealed that the ctu2 mutation did not enhance translation of the mRNA containing a thermospermine-responsive uORF of SAC51, but instead significantly reduced translation of that of SACL3, a member of the SAC51 family, and that of LONESOME HIGHWAY (LHW), which contains another conserved uORF in the 5′ leader region. Polysome profiling further demonstrated decreased association of SACL3 and LHW mRNAs with actively translating ribosomes in ctu2. Genetic interaction analyses supported the conclusion that the suppression of excessive xylem formation in acl5 by ctu2 is attributable to reduced LHW activity. In addition, ctu2 mutants displayed increased sensitivity to exogenous thermospermine, resembling the response of lhw mutants. Together, our results reveal that tRNA thiolation contributes to uORF-mediated translational regulation of key developmental regulators and identify tRNA modification as an important regulatory layer controlling vascular development. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 1055-7903 223 2026 Reticulate evolution, introgression, and recent diversification in Epimedium sect. Macroceras 108646 EN Emi Kusatake Department of Biology, Okayama University Momoka Konishi Department of Biology, Okayama University Shuto Tomokuni Department of Biology, Okayama University Yosuke Yanagi Department of Biology, Okayama University Shungo Kariyama Society of Kurashiki Museum of Natural History Takehito Itoh School of Life Science and Technology, Institute of Science Tokyo Atsushi Toyoda Department of Genomics and Evolutionary Biology, National Institute of Genetics Seung-Chul Kim Department of Biological Sciences, Sungkyunkwan University Makiko Mimura Department of Biology, Okayama University Hybridization can hinder or promote diversification, and growing genomic evidence suggests that it can facilitate adaptation and speciation. Despite recent progress, however, the quantitative contribution and temporal scope of hybridization to diversification remain poorly understood. The genus Epimedium is a recently diverged lineage, and sect. Macroceras largely consists of endemic species in Japan that are distributed across diverse environments, including limestone, serpentine, coastal habitats, heavy-snow regions, and regions with mild winters. Although natural hybridization and hybrid species have been reported in this section, molecular evidence demonstrating the contribution of hybridization to lineage diversification is limited. We reconstructed phylogenetic relationships using genome-wide single-nucleotide polymorphism (SNP) data from Epimedium sect. Macroceras and tested for genomic signatures consistent with hybridization. Phylogenetic analyses suggest that E. koreanum from Korea is sister to Japanese Epimedium lineages, consistent with an initial colonization of Japan from the Korean Peninsula. The analyses also revealed complex relationships among Japanese species and frequent signals of historical interspecific introgression. Our results are consistent with a history of recent diversification in sect. Macroceras accompanied by introgressive hybridization, which may have contributed to diversification across heterogeneous environments in Japan. This study provides the first genome-wide insights into the evolutionary history of Epimedium sect. Macroceras and reveals complex reticulate relationships among the lineages. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0924-4247 408 2026 A flexible PVDF-based galloping flow sensor 117978 EN Mitsuki Kurose Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takefumi Kanda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuya Sato Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Shuichi Wakimoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Daisuke Yamaguchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Shinji Hiejima Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takeji Ueda Hydro-VENUS Co., Ltd., Okayama University Effective monitoring of low flow velocities in small rivers and irrigation channels is hindered by the power requirements and maintenance costs of existing technologies. This study proposes a novel flexible piezoelectric polymer flow sensor utilizing galloping vibration to detect flow velocity in the low range (≤ 0.1 m/s). The sensor features a flexible cantilever structure composed of a silicone rubber beam embedded with a polyvinylidene fluoride (PVDF) film and a tip pillar. Unlike conventional devices based on flow-induced vibration, the use of low-stiffness materials enables the induction of self-excited vibration even under weak fluid forces. Computational fluid dynamics (CFD) analysis has been conducted to optimize the tip shape; a D-shaped semicylinder is selected over a cylinder and a square prism because the geometry maximizes the lift force per unit mass, ensuring efficient energy conversion. To predict sensor behavior, a coupled mechanical-fluid-electrical model was developed. Specifically, the model accounts for the static deflection angle caused by fluid drag. Water channel experiments demonstrated that sensors with beam thicknesses under 4 mm successfully generated stable periodic outputs at 0.1 m/s, a regime previously difficult for galloping-based devices. Conversely, thicker beam which has a thickness of 8 mm achieved higher outputs at higher velocities but failed to actuate at low speeds. Furthermore, the study showed a vibration suppression phenomenon in flexible beams at high flow velocities due to excessive static deflection, which was accurately reproduced by the analytical model. These findings establish structural stiffness as the critical design parameter for optimizing the operable velocity range of flow sensors. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0924-4247 408 2026 Tip position estimation of a 3-DOF soft mechanism using artificial muscles with optical fibers 117938 EN Rikimaru Okada Graduate School of Environment, Life, Natural Science and Technology, Okayama University Shuichi Wakimoto Graduate School of Environment, Life, Natural Science and Technology, Okayama University Yuichiro Toda Graduate School of Environment, Life, Natural Science and Technology, Okayama University Shun Miura Graduate School of Environment, Life, Natural Science and Technology, Okayama University Daisuke Yamaguchi Graduate School of Environment, Life, Natural Science and Technology, Okayama University Takefumi Kanda Graduate School of Environment, Life, Natural Science and Technology, Okayama University McKibben-type pneumatic artificial muscles (PAMs) are lightweight and flexible soft actuators with a high power-to-weight ratio, and have been widely applied to rehabilitation devices, power-assist systems, and soft robotic mechanisms. By integrating sensing functions into PAMs, their usability and controllability can be enhanced, enabling the development of more practical and advanced soft mechanisms. We previously proposed a smart artificial muscle (SAM) by integrating an optical fiber into the braided sleeve of a McKibben-type PAM, which enables displacement estimation by measuring optical bending loss. The SAM is compatible with conventional PAM fabrication processes; however, the sensor output exhibits strong nonlinearity and time dependency. In this study, an LSTM-based state estimation framework is extended from a single SAM to a three-degree-of-freedom soft mechanism composed of multiple SAMs, where strong nonlinear coupling and mutual interference arise among actuators. In the proposed framework, the LSTM model jointly processes time-series data of multi-channel optical sensor outputs and applied pressures of the three SAMs, along with past estimated states as inputs. This structure enables the model to capture nonlinear coupling, hysteresis, and time-dependent behavior, allowing estimation of the tip position of the soft mechanism. Experimental results demonstrate that the proposed method accurately captures complex nonlinear dynamics and mutual mechanical interference among multiple SAMs, achieving accurate tip position estimation. These results indicate that SAMs with integrated sensing and actuation capabilities, combined with machine-learning-based estimation, provide an effective approach for state estimation of multi-DOF soft robotic mechanisms. No potential conflict of interest relevant to this article was reported.

Hrvatski Sumarski Institut (Croatian Forest Research) Acta Medica Okayama 1849-0891 17 1 2026 Understory Vegetation Structure in Remnant Natural Forests and Acacia Plantations on Coastal Sand Dunes in North Central Vietnam 26007 EN Tuan Quoc Doan Okayama University, Graduate School of Environmental, Life, Natural Science and Technology Tetsuya K. Matsumoto Ibaraki University, Graduate School of Science and Engineering Tai Tien Dinh Hue Union of Science and Technology Associations (HUSTA) Hung Thai Le Hue University, University of Agriculture and Forestry Tuan Ngoc Anh Ho Hue Union of Science and Technology Associations (HUSTA) Naoko H. Miki Okayama University, Graduate School of Environmental, Life, Natural Science and Technology Hoang Thai Dac Ho Hue Union of Science and Technology Associations (HUSTA) Muneto Hirobe Okayama University, Graduate School of Environmental, Life, Natural Science and Technology In the coastal sand dune forests of North Central Vietnam, vegetation has been seriously damaged by war and overexploitation. To recover ecosystem functions, including sand stabilisation under harsh environments, exotic species like Acacia spp. have been planted as a monoculture. However, the long-term sustainability of this practice remains unclear. To assess the long-term effectiveness of revegetation with Acacia spp., this study aims to understand the differences and similarities in ecological characteristics of remnant natural forests and Acacia plantations on the coastal sand dune of North Central Vietnam by comparing understory vegetation structure and environmental conditions. We investigated the understory vegetation (height < 130 cm) in a total of 54 quadrants (1 m × 1 m), including nine natural forests and nine Acacia plantations. We compared diversity indices by mixed ANOVA and examined the differences in the understory vegetation structure between the two forest types through PERMANOVA. We also determined some abiotic environmental factors (e.g. light and soil water availability, and soil pH). We identified 951 individuals, with 792 found in natural forests and 159 in plantations. The species found in natural forests were well-distributed among Liana phanerophytes (Lp), Microphanerophytes (Mi), Mega-Mesophanerophytes (MM), and Cryptophytes (Cr). In contrast, species found in plantations were predominantly Cr, Hemicryptophytes (Hm), and MM. All diversity indices were significantly higher in natural forests (P < 0.05), and the NMDS analysis confirmed significant differences in the understory vegetation structure between natural forests and plantations. Only soil pH was significantly lower in natural forests (P < 0.05), while none of the environmental factors had a statistically significant impact on the variations in understory vegetation structure. Our results indicate that succession by native tree species does not seem to occur naturally in Acacia plantations. Hence, to restore and sustainably develop coastal sand dune forests in North Central Vietnam, it is essential to establish a scientifically based strategy for managing and protecting the remaining natural remnant forest areas. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0178-8051 2026 Uniqueness of Dirichlet forms for random point fields in the absence of tail triviality EN Yosuke Kawamoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama university We consider an infinite system of interacting Brownian motions that preserves a given random point field invariant. Such dynamics are constructed using Dirichlet form theory, which naturally leads to two Dirichlet forms for the random point field: the upper and the lower Dirichlet forms. A fundamental question is the uniqueness of the Dirichlet form: that is, whether these two forms coincide. This uniqueness has often been imposed as a key assumption in the Dirichlet form approach to the stochastic analysis for infinite particle systems. A sufficient condition for the uniqueness of the Dirichlet forms is known when the random point field is tail trivial. However, tail triviality has been established for only a limited class of random point fields. In this paper, we prove the uniqueness of the Dirichlet form without assuming tail triviality. The main contribution of this work is to establish the tail preserving property, which asserts that global properties of the system, such as particle density, are preserved under time evolution. As a consequence, our results also imply the strong uniqueness of solutions to the associated infinite-dimensional stochastic differential equations. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2041-1723 17 1 2026 Photooxidative Copper(II) Catalysis for Promoting anti-Markovnikov Hydration of Alkenes 3003 EN Naoki Oku Division of Applied Chemistry, Okayama University Keito Fuke Division of Applied Chemistry, Okayama University Rikako Masui Division of Applied Chemistry, Okayama University Ken Yamazaki Division of Applied Chemistry, Okayama University Yasunori Matsui Department of Applied Chemistry, Graduate School of Engineering, Osaka Metropolitan University Hiroshi Ikeda Department of Applied Chemistry, Graduate School of Engineering, Osaka Metropolitan University Tomoya Miura Division of Applied Chemistry, Okayama University Photoredox catalysis enables the generation of radical intermediates under mild conditions, yet photoredox catalysts have heavily relied on precious transition metal complexes. Therefore, the development of photocatalysts based on earth-abundant metals is increasingly demanded. Here, we report a highly photooxidative capability of a heteroleptic copper(II) complex for promoting anti-Markovnikov hydration of alkenes. The copper(II) complex containing bathophenanthroline and 3,4-dimethoxybenzenethiolate ligands is generated in situ from copper(II) chloride dihydrate. Upon visible-light irradiation, the copper(II) complex is photoexcited and exhibits an excited-state lifetime sufficiently long to oxidize various alkenes, including aliphatic substrates. Consequently, anti-Markovnikov hydration can be achieved under mild conditions, and the late-stage functionalization of natural products and pharmaceutical derivatives is also feasible. The developed catalytic system can be extended for photooxidative reactions of alkenes, such as intramolecular cyclization reactions and anti-Markovnikov addition of nucleophiles other than water. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 1999-4907 17 5 2026 Photosynthetic Response of Larix gmelinii var. japonica Saplings After Exogenous Glutathione Foliar Application 530 EN Resa Sri Rahayu Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Wataru Ishizuka Forestry Research Institute, Hokkaido Research Organization Ayu Narita Forestry Research Institute, Hokkaido Research Organization Rie Miyata Forestry Research Institute, Hokkaido Research Organization Naoko H. Miki Faculty of Environmental, Life, Natural Science and Technology, Okayama University Hirokazu Kon Forestry Research Institute, Hokkaido Research Organization Yuko Miyazaki Faculty of Environmental, Life, Natural Science and Technology, Okayama University Sapling survival and growth depend on photosynthetic assimilates. Therefore, improving physiological performance during early stages may enhance subsequent performance and nursery production. This study evaluated whether exogenous oxidized glutathione (GSSG), reported to enhance photosynthesis, improves the photosynthetic, physiological, and growth-related traits of Larix gmelinii var. japonica saplings. Sixteen saplings were assigned to four treatments: GSSG, 5-aminolevulinic acid, Hyponex, and a water control. Photosynthetic, nitrogen-related, and growth traits were measured before treatment and at 3, 6, 13, and 31 days after treatment, and biomass was assessed after three months. The GSSG treatment showed no difference in the net CO2 assimilation rate (Amax) compared with the control, but exhibited a significantly earlier peak at 6 days than the other treatments. This response was supported by the stability of GSSG-treated saplings against photoinhibition (Fv/Fm) and a tendency toward greater resilience to midday light stress (ΦPSII). Enhanced photosynthetic performance was associated with reduced carbon and nitrogen fluctuations and was accompanied by numerically greater root and stem biomass in the 2024 terminal shoots. Although fertilization effects were generally weak and transient, GSSG elicited notable responses, suggesting that the immediate enhancement of photosynthesis underlies its impact. However, its antioxidant properties under stressful conditions warrant further investigation. No potential conflict of interest relevant to this article was reported.

American Geophysical Union (AGU) Acta Medica Okayama 0094-8276 53 2 2026 Davemaoite Elasticity Reveals Slab‐Induced Heterogeneity in the Mantle Transition Zone e2025GL118147 EN Yingxin Yu State Key Laboratory of Precision Geodesy, School of Earth and Space Sciences, University of Science and Technology of China Xinyue Zhang State Key Laboratory of Precision Geodesy, School of Earth and Space Sciences, University of Science and Technology of China Dongzhou Zhang GeoSoilEnviroCARS, University of Chicago Luo Li State Key Laboratory of Precision Geodesy, School of Earth and Space Sciences, University of Science and Technology of China Zhu Mao State Key Laboratory of Precision Geodesy, School of Earth and Space Sciences, University of Science and Technology of China Ningyu Sun State Key Laboratory of Precision Geodesy, School of Earth and Space Sciences, University of Science and Technology of China Denglei Wang State Key Laboratory of Precision Geodesy, School of Earth and Space Sciences, University of Science and Technology of China Jing Li State Key Laboratory of Precision Geodesy, School of Earth and Space Sciences, University of Science and Technology of China Chaoshuai Zhao State Key Laboratory of Precision Geodesy, School of Earth and Space Sciences, University of Science and Technology of China Cheng Qian State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences Yingzhan Wei State Key Laboratory of High Pressure and Superhard Materials, College of Physics, Jilin University Xinyang Li State Key Laboratory of High Pressure and Superhard Materials, College of Physics, Jilin University Yuzhu Wang Shanghai Advanced Research Institute, Chinese Academy of Sciences Takayuki Ishii Institute for Planetary Materials, Okayama University The observed 2%–7% low-shear velocity (VS) anomalies near the subducted slab at the bottom mantle transition zone (MTZ) indicate strong lateral heterogeneity, which is commonly attributed to subducted oceanic crust. However, davemaoite, a major constituent of the subducted oceanic crust, has been poorly constrained in its elasticity, hindering accurate velocity modeling and obscuring the origin of these low-velocity features. Here we report single-crystal elasticity of Ti-bearing davemaoite with the composition of Ca(Si0.57Ti0.43)O3 under high pressure-temperature and found that Ti incorporation significantly reduces velocities and alters the pressure dependence of the shear modulus. Further velocity modeling demonstrated that subducted crusts with varying Ti content have seismic signatures of 1.7(2)–6.8(5)% low-VS at the bottom MTZ, consistent with the observed low-VS structure in the region. These findings highlight the role of slab-derived chemical heterogeneity in generating mantle seismic anomalies and provide new experimental constraints on the structure and dynamics of the deep Earth. No potential conflict of interest relevant to this article was reported.

Frontiers Media SA Acta Medica Okayama 1664-042X 17 2026 Bee larvae ameliorate andropause-like symptoms via a hormone-independent, antioxidant mechanism 1850114 EN Takashi Ito Department of Biology, Faculty of Environmental, Life, Natural Science and Technology, Okayama University Nobuaki Okumura Institute for Bee Products & Health Science, Yamada Bee Company, Inc. Takumi Oti Department of Biology, Faculty of Environmental, Life, Natural Science and Technology, Okayama University Hirotaka Sakamoto Department of Biology, Faculty of Environmental, Life, Natural Science and Technology, Okayama University Late-onset hypogonadism (LOH), also known as the male menopause, is characterized by a decline in sexual function as well as various physical and psychological symptoms, including anxiety. Although bee larvae have historically been utilized as a traditional food and medicine, their efficacy and physiological mechanisms of action against male menopausal symptoms remain unclear. In this study, we investigated the effects of bee larvae (BL) on sexual and anxiety-like behaviors using two rodent models of the male menopause: aged rats and castrated mice. In the aged rat model (64 weeks old), dietary BL supplementation for 4 weeks significantly attenuated the age-associated decline in ejaculation frequency compared to controls, while no significant effects were observed on mount or intromission frequencies. Notably, plasma analysis revealed no significant differences in testosterone or dihydrotestosterone levels between the BL and control groups. To elucidate the underlying mechanism, we evaluated sexual function using a castrated mouse model. While BL supplementation did not affect sexual behavior in intact mice, post-castration BL treatment significantly shortened intromission latency without altering mount frequency. In the elevated plus maze test, BL significantly alleviated castration-induced anxiety-like behaviors and improved exploratory activity. Furthermore, in vitro assays demonstrated that the BL extract exerts potent protective effects against oxidative stress, a pathological factor contributing to both erectile dysfunction and anxiety. These results suggest that BL improves erectile function and anxiety via hormone-independent mechanisms, potentially by mitigating oxidative stress in vascular and neural tissues. Thus, bee larvae represent a promising functional food for ameliorating the multi-faceted physical and psychological symptoms associated with male menopause. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Evolution of fruit shape diversity in polyploid cultivated persimmon EN Ayano HORIUCHI Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 The role of TFAM-mediated mitochondrial DNA replication in mouse oocytes EN DO QUANG SON Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Study on the mechanisms regulating bovine oviductal tonus during peri-ovulatory period EN Sayaka KUBOTA Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Molecular and Functional Characterization of Ion Transporters in Rice and Barley: Roles in Salinity Stress Tolerance EN SHAHIN IMRAN Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 ゴミムシダマシ類におけるオス間闘争が繫殖生態に及ぼす影響 EN Teruhisa MATSUURA Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 外来種タイリクシロフチタナゴの対策に向けた基礎生態学的研究 EN Rintaro TANIGUCHI Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Scale-invariant patterning and sequential digit formation via Shh/Fgf8 spatiotemporal dynamics in axolotl limb regeneration EN Saya FURUKAWA Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Mechanisms of Dermal Type I Collagen Formation in the Axolotl Skin EN Ayaka OHASHI Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Identification and functional characterization of novel suppressor genes for thermospermine-deficient mutants in Arabidopsis thaliana EN Yuichi NISHII Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Translational research on neural mechanisms of male sexual function and antioxidant intervention in mammals EN Takashi ITO Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Electroreductive Organic Transformations with a Catalytic Amount of Electricity EN Mayu FUJII Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 マイクロ波による結晶性炭素の合成と物性評価 EN Miyu KANEDA Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Studies on Synthesis and Photophysical Properties of Highly-Functionalized Phenacenes and Helicenes EN Keito NOSE Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Development of a Hydrodynamic-Simulation-Informed Random Forest Method for Efficient Spatiotemporal Flood Prediction EN KEXIN LIU Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Development of a low-cost crack displacement monitoring system for concrete structures EN AFIA SARAH BONEY Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 地域防災計画における「災害予防」「災害応急対策」の課題と解決策に関する研究 EN Junko KANETO Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Non-Interactive and Dynamic Secret Sharing Schemes for Threshold Cryptography EN YIXUAN HE Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 リングオシレータ型乱数生成回路における確率統計を用いた特徴分析に関する研究 EN Ryoichi SATO Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Hardware-Oriented Security Framework for Enhancing Side-Channel Attack Resistance in Embedded Cryptographic Systems EN Masaki HIMURO Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 A Study of SQL Programming Learning Assistant System for Novice Learners EN NI WAYAN WARDANI Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 A Study of Flutter Programming Learning Assistant System with User Interface Validation and Home Garden Monitoring Application EN SOE THANDAR AUNG Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 A Study of Audio-to-Text Conversion Software and Its Applications to Meeting Minutes and Slide Annotation Generation Tools EN AMMA LIESVARASTRANTA HAZ Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Comprehensive Studies of Nearby Core-Collapse Supernovae with Neutrinos in Super-Kamiokande EN Fumi NAKANISHI Graduate School of Environmental, Life, Natural Science and Technology, Okayama University No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 歯車の面圧疲労に及ぼす表面特性と潤滑油添加剤の影響 EN Takuya OHNO Graduate School of Natural Science and Technology, Okayama university No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Automated Design of Microwave Planar Circuits Using Genetic Algorithms and its Acceleration Techniques with Machine Learning Methods EN Takuma AKADA Graduate School of Natural Science and Technology, Okayama university No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 A Business-to-Business Collaboration System That Promotes Data Utilization While Encrypting Information on the Blockchain EN Hiroaki NASU Graduate School of Natural Science and Technology, Okayama university No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 Localization of Asgard Archaeal ESCRT Proteins to Eukaryotic Cellular Structures Reveals Conserved Mechanisms Underlying Eukaryotic Cellular Complexity EN NARIPOGU KISHORE BABU Graduate School of Natural Science and Technology, Okayama university No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2026 キイロショウジョウバエの色覚に関わるロドプシン発現の制御機構 EN Xuanshuo ZHANG Graduate School of Natural Science and Technology, Okayama university No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1445-5781 25 2026 TFAM-Mediated mtDNA Replication is Essential for Developmental Competence of In Vitro Grown Oocytes e70031 EN Son Quang Do Department of Animal Science, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hidetaka Tasaki Department of Animal Science, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hiroaki Funahashi Department of Animal Science, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takuya Wakai Department of Animal Science, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Purpose<br> Mitochondria are essential for oocyte maturation and early embryonic development, supplying ATP and maintaining mitochondrial DNA (mtDNA) integrity. During oogenesis, mtDNA undergoes dramatic amplification, but the mechanisms and functional significance of this process remain unclear. The purpose of this study was to elucidate the role of mitochondrial transcription factor A (TFAM) in mouse oocytes using an in vitro growth (IVG) system.<br> Methods<br> Oocytes at different growth stages were analyzed for mtDNA copy number and expression of mitochondrial biogenesis genes. To assess TFAM function, siRNA targeting Tfam was microinjected into secondary follicles, which were then cultured for 12 days under IVG conditions. Following culture, oocyte growth, mtDNA content, mitochondrial membrane potential, and developmental competence after in vitro fertilization (IVF) were evaluated.<br> Results<br> mtDNA copy number increased nonlinearly during oocyte growth, with a pronounced rise at the secondary follicle stage accompanied by TFAM upregulation. TFAM knockdown reduced mtDNA copy number and mitochondrial function without affecting oocyte size or meiotic maturation, but significantly decreased blastocyst formation and total cell numbers per blastocyst.<br> Conclusions<br> TFAM-mediated mtDNA replication is crucial for mitochondrial function and developmental competence of IVG-derived oocytes, underscoring its importance in early embryonic development. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2633-0679 7 1 2026 Programmable synthesis of alkaloidal frameworks integrating Michael acceptor generates covalent probes for targeting POLE3 in HBV replication 105 119 EN Nobuto Kaneko Department of Chemistry, Graduate School of Science, The University of Tokyo Misao Himeno Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo Yuhi Kobayashi Department of Chemistry, Graduate School of Science, The University of Tokyo Ryo Tanifuji Department of Chemistry, Graduate School of Science, The University of Tokyo Hiroki Kubota Department of Applied Chemistry, Graduate School of Engineering, Tokyo University of Agriculture and Technology Haruki Mizoguchi Graduate School of Natural Science and Technology, Okayama University Makoto Muroi Centre for Sustainable Resource Science, RIKEN Takehiro Suzuki Centre for Sustainable Resource Science, RIKEN Masaya Sugiyama Department of Viral Pathogenesis and Control, National Institute of Global Health and Medicine, Japan Institute for Health Security Naoshi Dohmae Centre for Sustainable Resource Science, RIKEN Hiroyuki Osada Centre for Sustainable Resource Science, RIKEN Taketomo Kido Laboratory of Cell Growth and Differentiation, Institute for Quantitative Biosciences, The University of Tokyo Atsushi Miyajima Laboratory of Cell Growth and Differentiation, Institute for Quantitative Biosciences, The University of Tokyo Hiroki Oguri Department of Chemistry, Graduate School of Science, The University of Tokyo The 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.

Fuji Technology Press Ltd. Acta Medica Okayama 1883-8014 30 3 2026 A Verification of Relationship Between Multiplicatively Weighted Voronoi Diagram and Huff Model: A Case Study on Order Assignment in E-Commerce 921 930 EN Takaki Kawamoto Faculty of Environmental, Life, Natural Science and Technology, Okayama University Takashi Hasuike Department of Industrial and Management Systems Engineering, School of Creative Science and Engineering, Waseda University This study examines the relationship between a multiplicatively weighted (MW-) Voronoi diagram and the Huff model. A mathematical comparison demonstrates that the models are structurally equivalent when the Huff model is deterministic and the distance decay parameter λ takes a specific value. This theoretical finding was empirically validated using real-world e-commerce order assignment data. The experiments demonstrate the distinct strengths of each model. The Huff model enables the flexible balancing of competing objectives through parameter adjustment, whereas the MW-Voronoi diagram provides geometric clarity in the interpretation of territories. We conclude that the selection of the two models should be guided by the problem objectives, depending on whether probabilistic flexibility or deterministic spatial partitioning is required. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2637-6105 8 9 2026 Ion-Conductive Vitrimers Based on Backbone-Type Triazolium Poly(Ionic Liquid)s: Counterion-Dependent Dynamics and Backbone Flexibility 6225 6235 EN Hikari Tsunekawa Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Atsushi Matsumoto Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, University of Fukui Yuya Iida Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Tsutomu Ono Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Takaichi Watanabe Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University To simultaneously achieve high ionic conductivity and recyclability, vitrimers were prepared using backbone-type triazolium poly(ionic liquid)s (TPILs) that integrate ionic transport and dynamic network rearrangement via trans-N-alkylation. TPIL elastomers bearing I–, BF4–, PF6–, and TFSI– counteranions were synthesized from “clickable” ionic liquid monomers, and their glass transition temperature (Tg), ionic conductivity, and vitrimeric dynamics were compared. Only the I–-based network exhibited stress relaxation at 170 °C, indicating that nucleophilic anions are important for bond exchange. However, a trade-off was observed between ionic transport and dynamic network rearrangement. We overcome this trade-off by mixing anions. Mixed-anion TPIL elastomers using I– and TFSI– exhibited lower Tg and higher ionic conductivity than I–-based elastomer, while still maintaining vitrimer-like relaxation. Rheological analysis revealed a decoupling between segment relaxation and bond exchange dynamics in vitrimer-like elastomers. The design combining flexible polymer backbones and mixed-anion engineering can create recyclable, highly conductive polymer electrolyte networks. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1557-1963 21 2026 Surface Plasmon Resonances in Silver Nanodendrites : Trunk Length and Branch Connectivity Dependence 2247 2258 EN Qingyuan Ma Graduate School of Informatics and Engineering, The University of Electro-communications Yuki Kishida Graduate School of Informatics and Engineering, The University of Electro-communications Nobuyuki Takeyasu Graduate School of Natural Science and Technology, Okayama University Satoru Shoji Graduate School of Informatics and Engineering, The University of Electro-communications This study systematically investigates how trunk length and branch connectivity govern surface plasmon resonances in silver nanodendrites in the infrared (IR) region using a computational modeling strategy. We show that a continuous conductive trunk is essential for exciting long-wavelength collective plasmon modes. In a simulated bottom-up construction scheme, the trunk length is gradually increased to conductively connect additional branches to the backbone. Our results reveal that the fundamental δ mode resonance can be deterministically tuned across the mid-infrared spectrum (from 3840 nm to 4360 nm) primarily by controlling the trunk connectivity. As the number of connected branches grows, the lowest-order collective resonance peak exhibits a systematic redshift, and its resonance wavelength scales linearly with the effective dipole length Leff of the electron oscillation path. Concurrently, new higher-order modes emerge as local resonances of the connected substructures. These observations indicate that interrupting the conductive pathway causes a global collective mode to decompose into multiple resonances associated with more weakly coupled subsystems. The established linear scaling relationship provides a highly predictable design rule for this “programmable” connectivity, offering a robust platform for advanced applications such as multi-spectral infrared imaging, selective chemical sensing, and surface-enhanced infrared absorption (SEIRA) spectroscopy, where precise, a priori control over narrow-band infrared resonances is essential. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0003-6862 2026 Effect of caffeine on life-history traits on the red flour beetle, Tribolium castaneum (Coleoptera: Tenebrionidae) EN Shine Shane Naing Okayama University (Graduate School of Environmental, Life, Natural Science and Technology) Teruhisa Matsuura Okayama University (Graduate School of Environmental, Life, Natural Science and Technology) Takahisa Miyatake Okayama University (Graduate School of Environmental, Life, Natural Science and Technology) Nowadays, addressing insect pest infestation effectively requires environmentally sound and sustainable pest control methods that minimize environmental pollution. Caffeine (1, 3, 7-trimethylxanthine), a plant-derived secondary metabolite, has insecticidal, hormonal and antifeedant properties, making it a promising and more sustainable alternative for pest management. In this study, the red flour beetle Tribolium castaneum Herbst (Coleoptera: Tenebrionidae), a serious stored pest, was used to investigate the effects of different caffeine concentrations on life-history traits. We applied two delivery methods: 1) oral exposure through a caffeine–sucrose solution for adults, and 2) dietary incorporation of caffeine powder mixed with wheat flour and brewer’s yeast for adults and their larvae. To evaluate the effect of caffeine on life-history traits, adult longevity, pupation rate, larval period, pupal weight, adult body size and food consumption were examined. Results revealed higher caffeine concentrations (> 1%) significantly reduced longevity, delayed pupation, decreased pupal number, pupal weight and adult body size in both males and females. Lower caffeine concentration (0.01%) increased pupal number but resulted in lower offspring quality, such as smaller pupal weight and adult size. The results show that caffeine has negative effects on life-history traits of T. castaneum, suggesting its potential use as a natural pesticide in caffeine-based sustainable pest-management programs and integrated pest management (IPM). No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1432-1076 185 6 2026 Drug-induced sarcoidosis-like reaction following IL-4/IL-13 receptor blockade by dupilumab 391 EN Kozo Yasui Department of Pediatrics, Dentistry and Pharmaceutical Science, Okayama University Graduate School of Medicine Masato Yashiro Okayama University Hospital Center for Innovative Clinical Medicine The purpose of the study is to review reported cases of dupilumab-associated drug-induced sarcoidosis-like reaction (DISR) and consider possible immunologic mechanisms. This short review aims to raise awareness of dupilumab-associated DISR and discuss safety considerations in pediatric patients.<br> Conclusion: Dupilumab is a human monoclonal antibody that reduces inflammation driven by T helper 2 (Th2) cells and is used to treat type 2 inflammatory disorders, including atopic dermatitis. The most common adverse reactions during the first year of treatment are local reactions at the injection site, conjunctivitis, and headache. Although DISR is rare, it has been documented in dupilumab-treated patients. We hypothesized that dupilumab shifts the Th1/Th2 equilibrium toward Th1 and granulomatous inflammation, which may present as DISR. We identified and reviewed 10 recently reported DISR cases and observed that reported features of DISR—including uveitis, optic neuritis and meningoencephalitis, bilateral hilar lymphadenopathy, and histopathologically noncaseating granulomas—can mimic systemic sarcoidosis. Discontinuation of dupilumab resulted in favorable outcomes in most reported DISR cases; however, symptoms worsened in some cases and sequelae became a concern. Case reports of DISR have so far been limited to adults or adolescents, but awareness of potential adverse effects of dupilumab remains important in pediatric patients. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2731-5894 2026 Comparative study of Ni–CeO2 catalysts prepared by impregnation and coprecipitation for CO2 methanation EN Nobuko Fukuda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Shuichi Imano Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nozomi Nakahara Graduate School of Environmental, Life, Natural Science and Technology, Okayama University This study explores how synthesis methods affect the structure and CO2 methanation performance of Ni–CeO2 catalysts prepared by coprecipitation and impregnation under identical conditions. Coprecipitation generated particles below 100 nm with uniform elemental distribution, together with large bulk-like particles exhibiting locally concentrated Ni species, attributed to differences in hydroxide solubility. Impregnation, by contrast, produced very large particles (> 500 nm) with smaller particles attached, while maintaining relatively homogeneous elemental distribution. Coprecipitated catalysts showed slightly higher surface area and oxygen vacancy concentration, resulting in higher apparent turnover frequencies (TOFapp) below 300 °C due to enhanced CO2 adsorption and high Ni site density. However, at temperatures above 350 °C, impregnated catalysts displayed higher CH4 selectivity and TOFapp, indicating reduced kinetic limitations and more efficient active-site utilization. These results provide insights for rational design of efficient CO2 methanation catalysts. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2574-0970 9 14 2026 Reversible Droplet Bridging and Tunable Viscoelasticity in Emulsions Using Biocompatible PLA-b-PEO-b-PLA Telechelic Block Copolymers: Implications for Injectable Emulsion Gels 6176 6185 EN Hinako Nakayama Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Atsushi Matsumoto Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, University of Fukui Yuya Iida Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Tsutomu Ono Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Takaichi Watanabe Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Telechelic polymers are known to form reversible networks through end-group association; however, their application as structuring agents in emulsion-based soft materials remains underexplored. Herein, we systematically investigate the biocompatible amphiphilic triblock copolymer poly(d,l-lactic acid)-block-poly(ethylene oxide)-block-poly(d,l-lactic acid)(PLA-b-PEO-b-PLA) as a rheology modifier in toluene-in-water model emulsions. Owing to the selective adsorption of PLA end blocks at the oil–water interface and the solvation of the PEO midblock in the aqueous phase, this polymer is expected to form reversible droplet-bridging networks. During the process, the polymer concentration, molecular weight of the mid and end blocks, and the dispersed phase volume fraction were adjusted, and the factors governing network formation were elucidated using oscillatory rheology and stress-relaxation measurements. The results show that anchoring of the PLA end blocks and PEO-mediated bridging predominantly control the strength and dynamic reversibility of the network. Step-strain experiments further reveal that the droplet-bridging interactions can be disrupted under large deformation and partially recover when small-strain conditions are restored, confirming the presence of reversible physical associations. These findings establish a molecular design strategy for biodegradable telechelic copolymers as effective and reprocessable structuring agents in emulsion gels. The shear-responsive, tunable, and reversible nature of the droplet-bridging network makes this material platform particularly suitable for injectable emulsion gels for advanced soft matter and biomedical engineering applications. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0935-9648 2026 Turning Unpredictable Biomolecule Adsorption to Controlled Corona Formation: Focus on Carbon Nanomaterials e23328 EN Yajuan Zou Research Institute for Interdisciplinary Science, Okayama University Yalei Hu CNRS, Immunology Immunopathology and Therapeutic Chemistry University of Strasbourg ISIS Jie Yu Graduate School of Human and Environmental Studies, Kyoto University Naoki Komatsu Graduate School of Human and Environmental Studies, Kyoto University Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Alberto Bianco Research Institute for Interdisciplinary Science, Okayama University With unique optical and physicochemical properties, carbon nanomaterials (CNMs), including carbon nanotubes, graphene-related materials, nanodiamonds, and carbon dots, are extensively explored as platforms for cancer diagnosis and treatment. However, in biofluids, CNMs spontaneously adsorb biomolecules to form an unpredictable corona, obstructing the implementation of their designed functions. In this review, we summarize how the intrinsic and acquired properties of CNMs affect protein corona formation, and the consequent biological and toxicological outcomes, as well as strategies to reshape the composition and structural organization of adsorbed proteins. This comprehensive knowledge will provide insights into developing CNMs with tailored corona and requested functions in cancer nanomedicine, advancing their translations into clinics. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0953-8194 38 4 2026 Type III CD38 is present in the membrane of neurosecretory vesicles and has a cytosol-facing catalytic domain in primate oxytocin neurons e70187 EN Tatsuki Miyamoto Department of Biology, Faculty of Environmental, Life, Natural Science and Technology, Okayama University Akari Matsushima Department of Biology, Faculty of Science, Okayama University Akito Otubo Department of Biology, Faculty of Environmental, Life, Natural Science and Technology, Okayama University Chihong Song Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences Kazuyoshi Murata Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences Takumi Oti Department of Biology, Faculty of Environmental, Life, Natural Science and Technology, Okayama University Hirotaka Sakamoto Department of Biology, Faculty of Environmental, Life, Natural Science and Technology, Okayama University CD38, an ADP-ribosyl cyclase that generates cyclic ADP-ribose (cADPR), is essential for Ca2+-dependent oxytocin release. However, its subcellular localisation and membrane topology within oxytocin neurones have remained unclear. We investigated the distribution and orientation of CD38 in oxytocin-producing neurones of Japanese macaques (Macaca fuscata) using immunoelectron microscopy combined with biochemical isolation of neurosecretory vesicles (NSVs). CD38 immunoreactivity was selectively detected on oxytocin-containing NSVs in axon terminals in the posterior pituitary and dendrites of the supraoptic nucleus, whereas vasopressin vesicles and the plasma membrane lacked detectable labelling. Cryo-electron microscopy confirmed the structural integrity of purified NSV fractions, and Western blotting verified the presence of CD38 protein within these fractions. Permeabilisation-dependent immunogold labelling further demonstrated that the NSV membrane localisation of CD38 and that the N-terminal region of CD38 is oriented toward the vesicle lumen, consistent with a type III membrane topology in which the catalytic domain faces the cytosol. This arrangement positions the active site near cytosolic NAD+, enabling localised cADPR production adjacent to Ca2+-mobilising channels that support regulated exocytosis. These findings identify, in primate oxytocin neurones, a previously unrecognised, vesicle-associated pool of CD38 with a cytosol-facing catalytic domain and provide a structural framework for understanding how intracellular type III CD38 contributes to neuropeptide release. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0969-0239 2026 Counterion condensation, ion pairing and scattering properties of carboxymethyl cellulose with mono- and di-valent ions EN Elmira Abbasi GharehTapeh Materials Science and Engineering Department, The Pennsylvania State University Takaichi Watanabe Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Ferenc Horkay Section on Quantitative Imaging and Tissue Sciences, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health Can Hou Institute of Physical Chemistry, RWTH Aachen University Carlos G. Lopez Materials Science and Engineering Department, The Pennsylvania State University Max Hohenschutz Institute of Physical Chemistry, RWTH Aachen University We study the scattering and conductometric properties of a semiflexible polyelectrolyte, carboxymethyl cellulose (CMC), with monovalent and divalent counterions in aqueous media without added salts. The scattering patterns for the magnesium salts of CMC display a broad shoulder instead of the scattering peak observed for the monovalent salts. This suggests weaker electrostatic repulsion between chains and a consequent loss of local order. The result is consistent with conductivity measurements, which reveal that the effective charge of the backbone for MgCMC is approximately half that of NaCMC. The decrease in charge density agrees with Oosawa–Manning condensation, which expects the charge density to be inversely proportional to the counterion valence. Alkali metal counterions show large differences in ion-pair formation but only a weak effect in counterion condensation. We suggest that paired ions are a subset of condensed ions. A review of different methods to evaluate counterion condensation, including potentiometry, osmometry and viscosity-based methods is presented. Qualitative agreement between these methods is found and possible reasons for the discrepancies are discussed. No potential conflict of interest relevant to this article was reported.

Japan Poultry Science Association Acta Medica Okayama 1346-7395 63 2026 Supplementation of 5-Aminolevulinic Acid Suppressed Body Weight Loss and Reduced Disease Severity During Eimeria tenella Infection in Broiler Chickens 2026010 EN Taqi Ahmad Hanif Laboratory of Animal Physiology, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Makoto Matsubayashi Department of Veterinary Science, Graduate School of Veterinary Sciences, Osaka Metropolitan University Toshimitsu Hatabu Laboratory of Animal Physiology, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University This study aimed to evaluate the effects of 5-aminolevulinic acid (5-ALA) supplementation in broiler chickens infected with Eimeria tenella. To assess these effects, chickens supplemented with 20 ppm 5-ALA (5-ALA group) were compared with non-supplemented controls (control group). Sporulated E. tenella oocysts (2.0 × 103 oocysts per animal) were administered orally to 2-week-old broiler chickens. Body weight was measured weekly, and fecal samples were collected daily from 4 to 15 days post-infection (dpi). Fecal oocyst shedding was quantified using the sucrose flotation method. Cecal tissues were collected at 5 dpi for histopathological analysis and lesion scoring. The animals in the 5-ALA group exhibited significantly greater weight gain and milder clinical signs than those in the control group. Fecal oocyst shedding was highest at 7 dpi in both groups; however, the 5-ALA group exhibited significantly lower oocyst output than the control group. The total number of fecal oocysts shed during the acute infection period was significantly lower in the 5-ALA group than in the control group. Histopathological analysis revealed that although both groups exhibited epithelial hyperplasia and E. tenella schizonts in the cecal submucosa, inflammatory cell infiltration, cecal tissue damage, and histological lesion scores were significantly lower in the 5-ALA group than in the control group. These results suggest that 5-ALA supplementation may mitigate the clinical, parasitological, and histological effects of E. tenella infection in broiler chickens. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2948-216X 3 1 2026 Compact potential sensor for spacecraft based on a silicon photonic waveguide 10 EN Kosei Otsuka Department of Physics and Electronics, Osaka Metropolitan University Wataru Takahama Faculty of Environmental, Life, Natural Science and Technology, Okayama University Rikuto Hojo Department of Space Systems Engineering, Kyushu Institute of Technology Takeki Higashiguchi Department of Physics and Electronics, Osaka Metropolitan University Kazuya Kikunaga Sensing Technology Research Institute, National Institute of Advanced Industrial Science and Technology Tomofumi Mogami Electrostatic Engineering DEPT, Kasuga Denki INC Kazuhiro Toyoda Department of Space Systems Engineering, Kyushu Institute of Technology Yasushi Takahashi Faculty of Environmental, Life, Natural Science and Technology, Okayama University Satellites charge up due to incoming electrons and ions, resulting in an electrical potential difference (ΔV) between the satellite and outer space. This can cause electrostatic discharge (ESD) events, damaging electronic devices. To reduce failures due to ESD, sensors monitoring the ΔV can be helpful. Due to spacecraft’s restrictions, the sensors should be as small as possible. While small potential sensors in terrestrial applications are often based on electrical conduction in semiconductors, such sensors are not suitable for space application due to a weak resistance to cosmic radiation and ESD. Here, we report a compact sensor based on another sensing method: the utilization of light absorption in a silicon photonic waveguide. We performed experiments in a vacuum chamber simulating the space plasma environment to demonstrate that the light attenuation in the waveguide depends on the ΔV. Our results further indicate that our sensor exhibits a high resistance to ESD. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0005-2728 1867 3 2026 Multiple structures of photosystem I-FCPI supercomplexes from a coccolithophore alga reveal a modular antenna organization 149588 EN Romain La Rocca Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Pi-Cheng Tsai Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Koji Kato Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yoshiki Nakajima Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Fusamichi Akita Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Jian-Ren Shen Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Photosystem I (PSI) converts light energy into chemical energy in photosynthesis, and forms supercomplexes with light-harvesting complexes (LHCI) in eukaryotes to enhance energy capture and transfer. Various numbers and organizations of both PSI core and LHCI subunits are observed in various organisms. A subgroup of haptophytes named coccolithophores play a major role in marine carbon cycle and CaCO3 production, and the light-harvesting antennas of them are named FCPs (fucoxanthin-chlorophyll a/c binding protein) because they bind chlorophyll c and fucoxanthin in addition to chlorophyll a. A structure of a large PSI-FCPI supercomplex containing 38 FCPI subunits has been reported from a coccolithophore Emiliania huxleyi recently (L. Shen et al., Science 389, eadv2132, 2025). Here we solved five cryo-electron microscopy (cryo-EM) structures of PSI–FCPI supercomplexes isolated from another coccolithophore Chrysotila roscoffensis with different detergents at resolutions ranging from 2.3 to 1.7 Å. These structures represent discrete PSI-FCPIs containing 1, 4, 6, 8 and 9 FCPI subunits, with FCPIs arranged in a modular fashion. Association of each FCPI module to the PSI core, as well as the arrangement of protein subunits and pigments, are revealed. Contributions of individual antenna modules to excitation energy transfer were calculated and compared with PSI–FCPI supercomplexes from other species of coccolithophores and haptophytes. These results pinpoint the assembly of stable PSI–FCPI supercomplexes in C. roscoffensis and provide insights into how antenna modules contribute to energy transfer in coccolithophores. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2399-3642 9 1 2026 Structural study of monomeric and dimeric photosystem I-LHCI supercomplexes from a bryophyte 146 EN Pi-Cheng Tsai Research Institute for Interdisciplinary Science, Advanced Research Field, Okayama University Romain La Rocca Research Institute for Interdisciplinary Science, Advanced Research Field, Okayama University Hiroyasu Motose Department of Biology, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Jian-Ren Shen Research Institute for Interdisciplinary Science, Advanced Research Field, Okayama University Fusamichi Akita Research Institute for Interdisciplinary Science, Advanced Research Field, Okayama University Photosystem I (PSI) is one of the two photosystems conserved from cyanobacteria to vascular plants, and associates with multiple light-harvesting complexes (LHCs) that capture and transfer solar energy. Liverworts such as Marchantia polymorpha occupy an early evolutionary position among land plants and faced major challenges during terrestrial adaptation, including desiccation, strong light, and UV radiation. We reveal the cryo-electron microscopic structures of PSI-LHCI monomer and homodimer from the liverwort M. polymorpha at resolutions of 1.94 and 2.52 Å, respectively. The high-resolution map allows identification of the cofactors of the monomer and reveal differences between the liverwort and moss, another clade of bryophytes. The PSI-LHCI monomer-monomer is stabilized by PsaG and PsaH interactions on the stromal side, which causes the bending and twisting of the homodimer. PsaM interacts with PsaB tightly, indicating a key role of PsaM in mediating the dimerization. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0039-9140 306 2026 Instrument-free quantitative colorimetric analysis using adsorption-band length in a packed silica gel column 129728 EN Sychanh Phonxayxiong Takashi Kaneta Department of Chemistry, Okayama University A simple and instrument-free colorimetric method for quantitative analysis is reported, in which analyte concentration is determined by measuring the length of a colored adsorption band formed in a packed silica gel column. The proposed method employs a miniature silica gel column that acts as a signal transducer after it adsorbs the colored compound from a solution during its flow in the column. The length of this band increases proportionally with analyte concentration, which enables quantitative detection via simple distance measurement. A theoretical model was developed to describe the relationship between solute concentration, adsorption behavior, and band propagation along the column. The principle was validated via the detection of both iron ions and enzyme-mediated glutamic acid. For Fe2+ analysis, the o-phenanthroline complexation method shows a level of sensitivity comparable to that of conventional spectrophotometry, which enables an almost quantitative recovery of trace iron in tap water. The limit of detection (LOD) and the limit of quantification (LOQ) were estimated to be 0.20 μM and 0.60 μM for the proposed method and 0.23 μM and 0.70 μM for spectrophotometry, respectively. The approach was further extended to glutamate detection using a cascade reaction involving glutamate oxidase and horseradish peroxidase with N-benzoyl leucomethylene blue as the chromogenic substrate. The LOD and the LOQ of the proposed method were 0.08 and 0.25 μM, and both values are superior to the 0.24 μM and 0.73 μM obtained using a microplate reader. By integrating preconcentration with a distance-based readout, this method provides a simple yet highly sensitive analytical platform and establishes distance as a quantitative signal for colorimetric detection. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0304-4238 361 2026 Far-red-enriched ultra-long-day conditions induce constitutive FT expression and rapid flowering in radish rootstocks, promoting graft-mediated floral induction in Brassicaceae crops 114818 EN Ko Motoki Graduate School of Environmental, Life and Natural Science and Technology, Okayama University Nami Kakita School of agriculture, Okayama University Tanjuro Goto Graduate School of Environmental, Life and Natural Science and Technology, Okayama University Ken-ichiro Yasuba Graduate School of Environmental, Life and Natural Science and Technology, Okayama University Efficient floral induction is essential for breeding and seed production in Brassicaceae crops, particularly for late-bolting cultivars and plant-vernalization–type species such as cabbage (Brassica oleracea L.), which require substantial time and labor for artificial flower induction. A graft-mediated floral induction method was recently developed for cabbage, enabling flowering without vernalization treatment by grafting cabbage scions onto radish (Raphanus sativus L.) rootstocks. Although high expression of florigen gene FLOWERING LOCUS T (FT) in the rootstocks is a key determinant of success, environmental conditions capable of inducing strong FT expression in radish have remained unclear. Here, we demonstrate that a far-red-enriched ultra-long-day photoperiod (ULD-FR) markedly upregulates expression of radish FT homolog RsFTa and greatly enhances graft-mediated floral induction in cabbage. Under the ULD-FR condition, RsFTa expression remained constitutively high throughout the day, with daily transcript abundance increasing more than tenfold compared with standard high red/far-red (R/FR) ratio long-day conditions that employed fluorescent lamps. FT protein accumulation in cabbage scions grafted onto radish rootstocks was also strongly elevated, resulting in rapid flowering approximately 30 days after grafting. ULD-FR also promoted flowering in rapid-cycling Brassica rapa and B. oleracea accessions, and induced flowering in a vernalization-requiring R. sativus cultivar without low temperature treatment, suggesting that the response may be broadly conserved across Brassicaceae. Because ULD-FR can be implemented using standard lighting equipment by adding an FR light source, it presents potential utility as a versatile tool for breeding-related applications, including generation advancement and flowering synchronization among divergent accessions. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0304-4203 276 2026 Determination of picomolar to sub-nanomolar trace metals in seawater using an alternative chelating resin 104642 EN Naoya Kanna Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hajime Obata Atmosphere and Ocean Research Institute, The University of Tokyo Yoshiko Kondo Graduate School of Fisheries and Environmental Sciences, Nagasaki University In this study, we investigated the potential use of a chelating resin that immobilizes an amine with an iminodiacetic acid group (InertSep ME-2) for trace-metal analysis in natural seawater. Seven trace metals (Mn, Fe, Co, Ni, Cu, Zn, and Pb) were quantitatively preconcentrated onto the InertSep ME-2 chelating resin, eluted with nitric acid, and analyzed using high-resolution inductively coupled plasma mass spectrometry. The blank values and detection limits obtained using our method were at the sub-nanomolar level for most trace metals. These blank values were generally comparable to, or lower than, those previously reported for other chelating resins, including NOBIAS Chelate PA-1 and Toyopearl AF-Chelate-650 M. The accuracy and precision of our method were confirmed by analyzing reference seawater samples, and the results for the open-water samples were consistent with those obtained in an independent laboratory. The established preconcentration procedure was successfully applied to determine trace metal concentrations in natural seawater collected from the northwestern Pacific Ocean. Our method, which employs the InertSep ME-2 chelating resin, is sufficiently accurate for studying trace metals in open-ocean water at picomolar- to sub-nanomolar-level concentrations. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2079-6447 5 2 2026 Solution-Processable Near-Infrared-Absorbing Dye: Thiophene-Substituted N-Phenylphenothiazine Radical Cations for Stable Thin Films 14 EN Masafumi Yano Faculty of Chemistry, Material and Bioengineering, Kansai University Kengo Sakai Faculty of Chemistry, Material and Bioengineering, Kansai University Minami Ueda Faculty of Chemistry, Material and Bioengineering, Kansai University Koichi Mitsudo Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yukiyasu Kashiwagi Osaka Research Institute of Industrial Science and Technology We report a π-extended N-phenylphenothiazine dye bearing thiophene substituents, designed to address the practical compromise between long-wavelength near-infrared (NIR) absorption and the isolability of a stable radical cation state. The target compound was synthesized via Suzuki–Miyaura cross-coupling and exhibited good solubility in common organic solvents. Cyclic voltammetry in dichloromethane showed a reversible one-electron oxidation at E0 = 0.19 V vs. Fc/Fc+. Chemical oxidation afforded the corresponding radical cation, which showed an intense NIR absorption maximum at 910 nm. DFT calculations support thiophene-induced narrowing of the HOMO–SOMO gap and predict a pronounced bathochromic shift of the main absorption band. The radical cation was isolated as a stable PF6− salt and readily processed into spin-coated films, which retained strong NIR absorption and remained stable for months under ambient conditions. No potential conflict of interest relevant to this article was reported.