Wiley Acta Medica Okayama 0018-019X 85 9 2002 A New Route for Preparation of 5-Deoxy-5-(hydroxyphosphinyl)- D-mannopyranose and -L-gulopyranose Derivatives 2608 2618 EN Tadashi Hanaya Center of Instrumental Analysis, Okayama University Hiroshi Yamamoto Department of Chemistry, Faculty of Science, Okayama University Starting from methyl 2,3-O-isopropylidene-α-D-mannofuranoside (5), methyl 6-O-benzyl-2,3-O-isopropylidene-α-D-lyxo-hexofuranosid-5-ulose (12) was prepared in three steps. The addition reaction of dimethyl phosphonate to 12, followed by deoxygenation of 5-OH group, provided the 5-deoxy-5-dimethoxyphosphinyl-α-D-mannofuranoside derivative 15a and the β-L-gulofuranoside isomer 15b. Reduction of 15a and 15b with sodium dihydrobis(2-methoxyethoxy)aluminate, followed by the action of HCl and then H2O2, afforded the D-mannopyranose (17) and L-gulopyranose analog 21, each having a phosphinyl group in the hemiacetal ring. These were converted to the corresponding 1,2,3,4,6-penta-O-acetyl-5-methoxyphosphinyl derivatives 19 and 23, respectively, structures and conformations (4C1 or 1C4, resp.) of which were established by 1H-NMR spectroscopy. No potential conflict of interest relevant to this article was reported.

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.

Elsevier BV Acta Medica Okayama 0008-6215 340 1 2005 Synthesis and structural analysis of 6-deoxy-6-hydroxyphosphinyl-d-fructopyranose derivatives 31 37 EN Tadashi Hanaya Department of Chemistry, Faculty of Science, Okayama University Kumiko Imai Department of Chemistry, Faculty of Science, Okayama University Yurij V. Prikhod’ko Department of Chemistry, Faculty of Science, Okayama University Hiroshi Yamamoto Department of Chemistry, Faculty of Science, Okayama University 3,4-Di-O-benzyl-6-deoxy-6-diethoxyphosphinyl-1,2-O-isopropylidene-β-d-fructofuranose (13) was prepared from the known 1,2-O-isopropylidene-6-O-tosyl-β-d-fructofuranose in five steps. Reduction of 13 with sodium dihydrobis(2-methoxyethoxy)aluminate, followed by the action of hydrochloric acid and then hydrogen peroxide, afforded the 6-deoxy-6-hydroxyphosphinyl-d-fructopyranose derivative. This was converted into the 1,2,3,4,5-penta-O-acetyl-6-deoxy-6-methoxyphosphinyl-d-fructopyranoses, whose structure and conformation were established by 1H NMR spectroscopy. No potential conflict of interest relevant to this article was reported.

The Japan Institute of Heterocyclic Chemistry Acta Medica Okayama 0385-5414 55 7 2001 Synthesis of 5-Deoxy-5-phosphinyl-D-galactopyranose Derivatives: New Phospha-Sugar Analogs of D-Galactose 1301 1309 EN Hiroshi Yamamoto Center of Instrumental Analysis, Okayama University Tadashi Hanaya Department of Chemistry, Okayama University Ken-ichi Sugiyama Department of Chemistry, Okayama University Yasushi Fujii Department of Chemistry, Okayama University Akihito Akamatsu Department of Chemistry, Okayama University The addition reaction of dimethyl phosphonate to 3,6-di-O-benzyl-1,2-O-isopropylidene-α-L-arabino-hexofuranos-5-ulose (11), followed by deoxygenation of 5-hydroxyl group, provided 5-deoxy-5-dimethoxyphosphinyl-D-galactofuranose derivative (13a). Reduction of 13a with sodium dihydrobis(2-methoxyethoxy)aluminate, followed by the action of hydrochloric acid and then hydrogen peroxide, afforded the first D-galactopyranose analog (15) having a phosphinyl group in the hemiacetal ring. This was converted into the 1,2,4-tri-O-acetyl-5-methoxyphosphinyl derivatives (16), whose structure and conformation were established by 1H-NMR spectroscopy. 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.

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.

Elsevier BV Acta Medica Okayama 0008-6215 306 1-2 1998 Effect of a phosphorus atom upon vicinal – coupling constants in pyranose derivatives having a C–P bond: Additivity rule for the effect of phosphorus substituents 157 162 EN Tadashi Hanaya Department of Chemistry, Faculty of Science, Okayama University Hiroshi Yamamoto Department of Chemistry, Faculty of Science, Okayama University Additivity constants for phosphorus were estimated for the prediction of vicinal 1H–1H coupling constants by means of an additivity rule in a series of pyranose analogs having phosphorus as the ring heteroatom. The experimental J values were well reproduced by employing the proposed additivity constants with a small overall root-mean-square difference of 0.32 Hz. The prediction of coupling constants was employed for the investigation of conformational equilibria of pyranose analogs having a phosphinyl group in the ring or on the ring-carbon. 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 0009-0352 102 3 2025 A Curve Fitting Method for Analyzing Starch Granule Size Distributions in Cereals 438 450 EN Rose McNelly John Innes Centre Amy Briffa John Innes Centre Georgia Yiasoumi John Innes Centre Cristobal Uauy John Innes Centre Ryo Matsushima Institute of Plant Science and Resources, Okayama University David Seung John Innes Centre Background and Objectives: The size distribution of starch granules is an important factor in determining the functional and nutritional properties of starch. However, a simple, standardized method for their analysis is lacking. Here, we developed an approach for estimating granule size parameters using a Python script that fits curves to volumetric granule size distributions generated using a Coulter counter. Findings: The bimodal size distribution of starch from most wheat and barley cultivars could be best described with a mixed distribution curve. A log-normal distribution was fitted to the small B-type granules, and a normal distribution was fitted to the large A-type granules, allowing estimation of their relative abundance and size parameters despite their overlapping size distributions. However, the optimal fitting is altered in wheat mutants with large perturbations in B-type granule content. In maize and rice, which have unimodal granule size distributions, size parameters were calculated by fitting a single normal distribution. Conclusions: Curve fitting is an effective approach for estimating starch granule size parameters in diverse cereals, particularly the Triticeae with A- and B-type granules. Significance and Novelty: We provide new tools and guidelines for the quantitative analysis of granule size in cereals. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0008-6215 338 16 2003 Stereoselectivity in deoxygenation of 5-hydroxy-5-phosphinyl-hexofuranoses (α-hydroxyphosphonates) 1641 1650 EN Tadashi Hanaya Department of Chemistry, Faculty of Science, Okayama University Ken-ichi Sugiyama Department of Chemistry, Faculty of Science, Okayama University Heizan Kawamoto Department of Chemistry, Faculty of Science, Okayama University Hiroshi Yamamoto Department of Chemistry, Faculty of Science, Okayama University The addition of dimethyl phosphonate to six different hexofuranos-5-uloses in the presence of DBU, followed by esterification with methoxalyl chloride and then radical reduction, afforded 5-deoxy-5-dimethoxyphosphinyl-d- and l-hexofuranoses. The stereoselectivity of the deoxygenation and possible transition-state models are discussed. No potential conflict of interest relevant to this article was reported.

Japan Institute of Heterocyclic Chemistry Acta Medica Okayama 0385-5414 66 1 2005 Synthesis of Phospholane 1-Oxide Having Oxygen Functional Groups from a 4-Bromobutylphoshinate Derivative 251 261 EN Tadashi Hanaya Department of Chemistry, Faculty of Science, Okayama University Shigeru Kawase Department of Chemistry, Faculty of Science, Okayama University Hiroshi Yamamoto Department of Chemistry, Faculty of Science, Okayama University Ethyl 4-bromo-2,3-dimethoxybutyl(phenyl)phosphinate (10a) was prepared from 2,3-di-O-methyl-L-threitol (12) in five steps. Reduction of 10a with sodium dihydrobis(2-methoxyethoxy)aluminate, followed by the action of hydrogen peroxide, afforded 3,4-dimethoxy-1-phenylphospholane 1-oxide (3), while the reaction of 10a with magnesium in boiling THF resulted in the formation of ethyl 2-methoxy-3-butenyl(phenyl)phosphinate (26). No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0969-806X 251 2027 A rule-based calculation approach to derive bone-suppressed chest X-ray images using photon-counting techniques 114493 EN Natsumi Kimoto Department of Radiological Science, Faculty of Health Sciences, Junshin Gakuen University Rina Nishigami Graduate School of Medical Sciences, Kanazawa University Takashi Asahara Department of Radiological Technology, Faculty of Health Sciences, Okayama University Mana Mitani Division of Radiology, Medical Support Department, Okayama University Hospital Daiki Kobayashi Graduate School of Medical Sciences, Kanazawa University Noriaki Akagi Division of Radiology, Medical Support Department, Okayama University Hospital Toshihiro Iguchi Department of Radiological Technology, Faculty of Health Sciences, Okayama University Takao Hiraki Department of Radiology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hiroaki Hayashi College of Transdisciplinary Sciences for Innovation, Kanazawa University Improving the visibility of lung nodules, which are often hidden by bone shadows and difficult to identify, remains a challenge in chest radiography. This study aims to develop an algorithm for generating novel bone-suppressed images using photon-counting techniques. The core idea of our algorithm is to fit photon interaction cross-sections to X-ray attenuation data measured with photon-counting detectors. Based on further calculations using the derived fitting coefficients, both density (ρ) and amount-of-substance concentration (mol) were determined. The product of these values produced a ρ×mol image exhibiting a clear bone-suppression effect. We conducted a virtual chest imaging simulation using 10 patient datasets acquired via clinical photon-counting computed tomography (PC-CT). The CT images were converted into ρ×mol images following the proposed processing procedure, and two-dimensional chest images were generated through projection. Quantitative evaluations confirmed that the proposed images achieved sufficient bone suppression. Furthermore, commercial software provided by a vendor was used to generate bone-suppressed images from conventional images projected from CT data. A comparable bone-suppression effect on the ribs was observed between the vendor-generated images and our proposed images, while lesion visibility (e.g., lung nodules) was preserved. Additionally, bone-suppression effects in our images were observed in the vertebrae and clavicles located outside the lung fields. Our research demonstrates the value of constructing general X-ray imaging systems using photon-counting detectors. No potential conflict of interest relevant to this article was reported.

AIP Publishing Acta Medica Okayama 0021-9606 165 10 2026 Scaled-charge ion force field optimized for individual ion partial molar volumes in water 104508 EN Aoi Taira Department of Chemistry, Faculty of Science, Okayama University Hiroyuki Katsuto Department of Chemistry, Faculty of Science, Okayama University Kanon Nakao Department of Chemistry, Faculty of Science, Okayama University Tomonari Sumi Graduate School of Engineering, Muroran Institute of Technology Kenichiro Koga Department of Chemistry, Faculty of Science, Okayama University We present an ion partial molar volume force field for common monovalent and divalent ionic species, including Li+, Na+, K+, Cs+, Mg2+, Ca2+, F－, Cl－, Br－, I－, OH－, and H3O+. When combined with the TIP4P/2005 water model, the force field enables quantitative investigations of ion-specific effects in both bulk and interfacial properties. The iPMV force field is developed based on a single guiding principle: the ion–water interaction parameters are optimized such that the experimental partial molar volume of each individual ion at infinite dilution―determined via the ultrasonic vibrational potential method―is reproduced by construction. An exception is made for the hydronium ion, for which we also provide an alternative interface-optimized model. The force field employs a charge scaling factor of 0.75 and adopts the Lorentz–Berthelot combining rules for cross-Lennard-Jones interactions, with specific modifications for divalent cations. A distinctive feature of the iPMV force field is that, despite its straightforward design, a single set of ion parameters consistently reproduces a wide range of experimental properties―from volumetric and interfacial properties to salting-out/in effects and transport coefficients. This robust performance suggests a fundamental correlation between the partial molar volumes of individual ions and the broader physical properties of aqueous electrolyte solutions. No potential conflict of interest relevant to this article was reported.

American Society for Microbiology Acta Medica Okayama 0099-2240 2026 Interaction with the N-acetylgalactosamine moiety facilitates pore formation by Cry4Aa toxin, thereby increasing its toxicity e00714-26 EN Mohammad Tofazzal Hossain Howlader Department of Entomology, Bangladesh Agricultural University Taiyo Tsutsui Applied Chemistry and Biotechnology Program, School of Engineering, Okayama University Kouichi Saito Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Tohru Hayakawa Applied Chemistry and Biotechnology Program, School of Engineering, Okayama University Cry4Aa is a mosquito-larvicidal toxin produced by Bacillus thuringiensis serovar israelensis. Cry4Aa exhibits a characteristic architecture comprising three domains (I, II, and III) and functions as a pore-forming toxin, consistent with many previously reported insecticidal Cry toxins. However, the mechanism preceding pore formation by Cry4Aa, including receptor recognition, remains to be elucidated. The present study examined the potential involvement of sugar moieties in the Cry4Aa mode of action, with a particular focus on the process of pore formation. Cry4Aa and the sugar N-acetylgalactosamine exhibited considerably increased binding affinity. Furthermore, N-acetylgalactosamine treatment significantly enhanced the toxicity of Cry4Aa against Culex pipiens mosquito larvae. In the presence of N-acetylgalactosamine, the binding of Cry4Aa to phosphatidylcholine liposomes increased by 1.4-fold. The presence of this sugar did not affect the single-channel conductance of Cry4Aa pores formed in artificial lipid bilayers; however, it did appear to increase the number of Cry4Aa pores per designated area. In silico molecular docking analysis revealed promising binding sites within the cavity, surrounded by the Cry4Aa domains. These results suggest that the interaction of Cry4Aa with N-acetylgalactosamine moieties is a vital step in the process of pore formation. This interaction may induce a conformational change in the Cry4Aa molecule that facilitates its insertion into the target membrane. No potential conflict of interest relevant to this article was reported.

Elsevier 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.

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.

Walter de Gruyter GmbH Acta Medica Okayama 2195-4720 7 3 2013 An Efficient Synthesis of Limipterin [2'-O-(2-Acetamido-2-deoxy-β- D-glucopyranosyl) -L- biopterin] via N2 - (N ,N -Dimethylamino )-methylene- 3-[2-(4-nitrophenyl)ethyl]-L-biopterin 110 112 EN Hiroshi Yamamoto Department of Chemistry, Faculty of Science, Okayama University Tadashi Hanaya Department of Chemistry, Faculty of Science, Okayama University Koichiro Harada Department of Chemistry, Faculty of Science, Okayama University Heizan Kawamoto Department of Chemistry, Faculty of Science, Okayama University Wolfgang Pfleiderer Universitat Konstanz, Fakultat fur Chemie 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.

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.

Georg Thieme Verlag KG Acta Medica Okayama 0936-5214 2006 13 2006 Novel Preparation of a 2′-O-Acetyl-1′-O-(4-methoxybenzyl)-l-biopterin Derivative, a Versatile Precursor for a Selective Synthesis of l-Biopterin Glycosides 2075 2078 EN Tadashi Hanaya Department of Chemistry, Faculty of Science, Okayama University Hiroki Toyota Department of Chemistry, Faculty of Science, Okayama University Hiroshi Yamamoto Department of Chemistry, Faculty of Science, Okayama University l-Rhamnose was converted, over a 13-step-sequence, into 2′-O-acetyl-N 2-(N,N-dimethylaminomethylene)-1′-O-(4-methoxybenzyl)-3-[2-(4-nitrophenyl)ethyl]-l-biopterin, an appropriately protected precursor of 1′-O- and 2′-O-monoglycosyl-l-biopterin. Thus, the first selective synthesis of these l-biopterin glycosides was accomplished by treatment of the precursor with either DDQ or sodium methoxide, then with tetra-O-benzoyl-α-d-glucopyranosyl bromide in the presence of silver triflate and tetramethylurea, followed by removal of the remaining protecting groups. 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.

American Geophysical Union (AGU) Acta Medica Okayama 0094-8276 52 17 2025 Phase Relations in the MgSiO3 System Associated With Hot Mantle Upwelling Across the 660 km Depth e2025GL115385 EN Artem Chanyshev Bayerisches Geoinstitut, University of Bayreuth Narangoo Purevjav Bayerisches Geoinstitut, University of Bayreuth Dmitry Bondar Bayerisches Geoinstitut, University of Bayreuth Hu Tang Bayerisches Geoinstitut, University of Bayreuth Hongzhan Fei Bayerisches Geoinstitut, University of Bayreuth Lin Wang Bayerisches Geoinstitut, University of Bayreuth Fei Wang Bayerisches Geoinstitut, University of Bayreuth Eun Jeong Kim Bayerisches Geoinstitut, University of Bayreuth Dan Liu Bayerisches Geoinstitut, University of Bayreuth Takayuki Ishii Institute for Planetary Materials, Okayama University Shrikant Bhat Deutsches Elektronen‐Synchrotron DESY Robert Farla Deutsches Elektronen‐Synchrotron DESY Tomoo Katsura Bayerisches Geoinstitut, University of Bayreuth The phase transformations of MgSiO3 bridgmanite control the structure, dynamics and chemistry of the Earth's mantle. Formation of bridgmanite occurs at a depth of about 660 km causing the strong and abrupt seismic discontinuity. Previous experimental studies have revealed that this discontinuity is caused by ringwoodite dissociation in the average mantle. However, the cause of the 660-km seismic discontinuity beneath hotspots remains unclear. Here we determine the phase relations in the MgSiO3 system near the 660-km seismic discontinuity conditions. At 2,200–2,350 K with decreasing pressure, MgSiO3 bridgmanite first transforms to akimotoite and then to garnet. The akimotoite-bridgmanite boundary has almost no temperature dependence, whereas the garnet–akimotoite transition has a very steep positive boundary slope. Based on these slopes, we calculated the garnet–bridgmanite boundary slope. Depending on the temperature regime, the akimotoite-bridgmanite or the garnet–bridgmanite transition may occur in ascending plume beneath hotspots near the 660 km depth. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1474-9718 25 5 2026 UNC45B Reduction With Aging: A Myofiber-Intrinsic Promoting Factor for Sarcopenia e70502 EN Taiga Mishima Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Taiga Nagamune Department of Life Science and Applied Chemistry, Nagoya Institute of Technology Saori Tada Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Daiki Watanabe Graduate School of Sport and Health Sciences, Osaka University of Health and Sport Sciences Nao Tokuda Graduate School of Health Sciences, Sapporo Medical University Takashi Yamada Graduate School of Health Sciences, Sapporo Medical University Akiko Hashimoto‐Hachiya Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Sayaka Higo‐Yamamoto Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Kohei Kido Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Noriyuki Nagaoka Advanced Research Center for Oral and Craniofacial Sciences, Dental School, Okayama University Aoi Ikedo Division of Integrative Pathophysiology, Proteo‐Science Center, PIAS, Ehime University Yuuki Imai Division of Integrative Pathophysiology, Proteo‐Science Center, PIAS, Ehime University Ryo Fujita Division of Regenerative Medicine, Transborder Medical Research Center, Institute of Medicine, University of Tsukuba Seiya Mizuno Laboratory Animal Resource Center in Transborder Medical Research Center, Institute of Medicine, University of Tsukuba Satoru Takahashi Laboratory Animal Resource Center in Transborder Medical Research Center, Institute of Medicine, University of Tsukuba Katsutaka Oishi Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Satoru Ato Faculty of Medical Science, Nippon Sport Science University Riki Ogasawara Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Skeletal muscle mass and force decline with age, and the loss of muscle force precedes muscle atrophy. However, the underlying mechanisms remain unclear. Here, we investigated the role of the myosin co-chaperone, uncoordinated mutant number-45 myosin chaperone B (UNC45B), in regulating muscle mass and force. UNC45B expression decreased in mouse gastrocnemius muscle with age, particularly at 24 months old, and adeno-associated virus vector-mediated knockdown of Unc45b in 3-month-old mouse triceps surae muscle first reduced plantar flexor torque and then decreased gastrocnemius muscle mass. In addition, Unc45b knockdown in the triceps surae muscle resulted in lower bone mineral density. While maximum Ca2+-activated force in mechanically skinned fibers was not affected by Unc45b knockdown, Unc45b knockdown decreased the ratio of depolarization-induced force to the maximum Ca2+-activated force. We established tamoxifen-inducible skeletal muscle-specific Unc45b knockout (Unc45b imKO) mice to investigate whether the muscle atrophy and weakness due to the loss of Unc45b impacts metabolism and behavior. We found that Unc45b imKO reduced muscle mass and force at a whole-body level, but did not influence systemic glucose tolerance, insulin sensitivity, or the respiratory exchange ratio. However, Unc45b imKO mice reduced the amount of deeper non-rapid eye movement sleep, locomotor activity, and body temperature during the sleep phase. We conclude that UNC45B is essential for maintaining fast-twitch muscle mass and muscle force. In addition, Unc45b deficiency-mediated muscle loss is also associated with bone fragility, decreased body temperature, and impaired sleep quality. 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. 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. 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.

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.

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.

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.

Springer Science and Business Media LLC Acta Medica Okayama 2045-2322 15 1 2025 Amyloid-forming property of the N-terminal 1－70 residues of human apolipoprotein A-IV 13203 EN Norihiro Namba Laboratory of Biophysical Chemistry, Kyoto Pharmaceutical University Tokiko Danjo Laboratory of Biophysical Chemistry, Kyoto Pharmaceutical University Yuichiro Kitagawa Laboratory of Biophysical Chemistry, Kyoto Pharmaceutical University Yoshito Naito Laboratory of Biophysical Chemistry, Kyoto Pharmaceutical University Takashi Ohgita Center for Instrumental Analysis, Kyoto Pharmaceutical University Toshinori Shimanouchi Graduate School of Environmental and Life Science, Okayama University Hiroyuki Saito Laboratory of Biophysical Chemistry, Kyoto Pharmaceutical University Apolipoprotein A-IV (apoA-IV), the largest member of the exchangeable apolipoprotein family, is a common constituent of amyloid deposits in renal and cardiac amyloidosis. In this study, we characterized the aggregation propensity of the apoA-IV N-terminal fragment to form amyloid fibrils using a variety of biophysical techniques. Thioflavin T fluorescence assay, circular dichroism measurement, and microscopic observations revealed that the N-terminal 1－70 amino acid fragment of apoA-IV readily forms amyloid fibrils by a transition from a random coil to a β-sheet-rich structure. Sequence-based analysis indicated that residues 7－16 and 38－42 are the major aggregation-prone segments within the N-terminal 1－70 residues of apoA-IV. Consistent with this, deletion of these residues strongly inhibited the β-transition and fibril formation of apoA-IV 1－70. Kinetic and thermodynamic analyses of fibril formation by the apoA-IV 1－70 fragment demonstrated that primary nucleation is the dominant step in fibril formation, for which the activation energy barrier is entirely entropic. In addition, we found that the presence of heparin, a representative glycosaminoglycan, accelerated fibril formation kinetics and enhanced the yield of apoA-IV 1－70 fibrils, and the positively charged residues K58-K59 play a critical role in heparin interaction. Overall, our results suggest that the strong amyloid-forming propensity of the N-terminal fragment of apoA-IV may play a key role in amyloid deposition associated with apoA-IV amyloidosis. 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.

Elsevier BV Acta Medica Okayama 0021-9258 302 8 2026 Proton pump rhodopsins for optogenetic manipulation of biological activities and beyond 113318 EN Keiichi Kojima Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Miyu Inokuchi Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuki Sudo Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Water (H2O), the principal component of living organisms including humans, dissociates into H+ and OH- in aqueous environments, and the resulting H+ concentration determines both cellular pH and the proton motive force (PMF) across cellular membranes. These physicochemical parameters are fundamental regulators of a wide range of biological processes. Optogenetics enables the manipulation of biological and cellular functions using light, typically through the ectopic expression of microbial rhodopsins as photoreceptive proteins in target cells or organs. This review provides a comprehensive overview of optogenetic studies employing H+ pump rhodopsins in diverse biological systems and highlights their growing relevance to neuroscience, cell biology, bioengineering, and therapeutic research. Notably, optical control of H+ concentration allows the precise modulation of neural and non-neural activities in animals and bacteria, highlighting the broad applicability and significant potential of H+ pump rhodopsins for optogenetics. Based on previous and current studies, we discuss how further expansion of the molecular toolkit of H+ pump rhodopsins could enable increasingly fine-tuned manipulation of intracellular pH dynamics and PMF for probing cellular physiology and designing next-generation therapeutic strategies and consider emerging directions that extend beyond classical optogenetics toward the optical control of bioenergetic and chemical processes. 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.

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.

Elsevier BV Acta Medica Okayama 0024-4937 542-543 2026 Serpentinization parageneses controlled by lithological variations among olivine gabbro and peridotite from the Atlantis Massif, Mid-Atlantic Ridge 108716 EN Toshio Nozaka Department of Earth Sciences, Okayama University Shun Kazumata Department of Earth Sciences, Okayama University Frieder Klein Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution Serpentinization of olivine impacts the geochemical and ecological environment via molecular hydrogen production, promoted by iron oxidation to form magnetite and ferric iron in serpentine. Previous studies suggested that serpentinization proceeds with various reactions and the extent of iron oxidation is variable depending on the reaction pathways. To examine the effect of lithological variation on reactions at an incipient stage of serpentinization, we carried out microscopic observations, electron-probe analyses, and Raman spectroscopy of serpentine veins cutting olivine in gabbroic rocks and peridotites from the Atlantis Massif, Mid-Atlantic Ridge. The results indicate that the serpentine veins in the proximity of olivine dominantly comprise lizardite mixed with variable minor phases or components depending on igneous lithology: brucite in peridotites, troctolites, and primitive olivine gabbros; cronstedtite-bearing serpentine, commonly without brucite, in some troctolites and slightly evolved olivine gabbros; and neither brucite nor cronstedtite component in evolved olivine gabbros. This suggests that incipient-stage serpentinization paragenesis is dominantly controlled by silica activity reflecting lithological variation. In addition to magnetite, the formation of cronstedtite in gabbroic rocks has the potential to produce hydrogen. The presence or absence of brucite and cronstedtite could affect the timing and magnitude of iron oxidation and hydrogen production during serpentinization. Considering the predominance of gabbroic rocks in the lower oceanic crust, the variation in incipient-stage serpentinization paragenesis in gabbroic rocks may have an impact on the redox state and ecological environment around the (sub)seafloor. 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.

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.

Wiley Acta Medica Okayama 1433-7851 64 22 2025 Efficient Nickel Precatalysts for Suzuki-Miyaura Cross-Coupling of Aryl Chlorides and Arylboronic Acids Under Mild Conditions e202504108 EN Morgan E. John School of Molecular Sciences, The University of Western Australia (M310) Michael J. Nutt School of Molecular Sciences, The University of Western Australia (M310) Josephine E. Offer School of Molecular Sciences, The University of Western Australia (M310) Jeremy A. Duczynski School of Molecular Sciences, The University of Western Australia (M310) Ken Yamazaki Division of Applied Chemistry, Okayama University Tomoya Miura Division of Applied Chemistry, Okayama University Stephen A. Moggach School of Molecular Sciences, The University of Western Australia (M310) George A. Koutsantonis School of Molecular Sciences, The University of Western Australia (M310) Reto Dorta School of Molecular Sciences, The University of Western Australia (M310) Scott G. Stewart School of Molecular Sciences, The University of Western Australia (M310) The synthesis and catalytic properties of Ni(II) complexes with the general formula Ni(NHC)[P(OR)3](Ar)Cl are described. These complexes are air-stable and extremely effective precatalysts in the Suzuki-Miyaura cross-coupling reaction. The reaction protocols described allow for the cross-coupling of aryl chlorides and arylboronic acids, employing low catalytic loading, to deliver a large variety of functionalized biaryl compounds. For the coupling of aryl chlorides with N-heterocyclic boronic acids, TBAF was used as an additive to afford nitrogen-containing biaryl products. Overall, these reaction protocols operate at room or mild temperatures and can be applied to a variety of electronically and sterically differentiated coupling partners. Fundamental insights into the mechanism of this reaction, including the proposed formation of the catalytically active Ni(NHC)[P(Oi-Pr)3] and resting state species, are also reported. 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.

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.

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.

Wiley Acta Medica Okayama 1433-7851 64 11 2025 Stereoselective Preparation and Palladium-Catalyzed Suzuki–Miyaura Cross-Coupling of Alkenyl Sulfoximines e202420949 EN Kosuke Yasui Department of Applied Chemistry Graduate School of Engineering, Osaka University Yuichiro Tomishima Department of Applied Chemistry Graduate School of Engineering, Osaka University Tomoya Miura Division of Applied Chemistry, Okayama University Ken Yamazaki Division of Applied Chemistry, Okayama University Koji Hirano Department of Applied Chemistry Graduate School of Engineering, Osaka University Although numerous transition-metal catalyzed cross-coupling reactions of alkenyl electrophiles with a sulfur(VI) leaving group, mainly alkenyl sulfones, have been developed, most rely heavily on highly nucleophilic Grignard reagents, and the use of organoboron reagents remains challenging. We report herein facile preparation and the following Pd-catalyzed Suzuki–Miyaura cross-coupling reaction of alkenyl sulfoximine, a monoaza analog of sulfone. The condensation of alkyl sulfoximine with aldehydes, developed in this study, makes alkenyl sulfoximines more readily available. The resulting alkenes undergo an unprecedented oxidative addition of the C－S bond to the Pd center. This cross-coupling proceeds with retention of its original stereochemistry and provided alkenes bearing three different functionalities in a stereoselective fashion. DFT calculations highlight the critical role of boronic acid and in situ-generated boroxines in facilitating this transformation. 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.

Springer Science and Business Media LLC Acta Medica Okayama 0342-1791 52 2 2025 The effect of Fe incorporation on the single-crystal elasticity of δ-AlOOH 18 EN Niccolò Satta Institut für Mineralogie, Universität Münster Giacomo Criniti Bayerisches Geoinstitut, Universität Bayreuth Tiziana Boffa Ballaran Bayerisches Geoinstitut, Universität Bayreuth Alexander Kurnosov Bayerisches Geoinstitut, Universität Bayreuth Takayuki Ishii Institute for Planetary Materials, Okayama University Johannes Buchen Bayerisches Geoinstitut, Universität Bayreuth Hauke Marquardt Department of Earth Sciences, University of Oxford The seismic mapping of hydrous materials in the Earth’s deep interior requires experimental constraints on the elastic anisotropy of hydrous minerals and phases. Oxyhydroxides like δ-(Al,Fe)OOH are arguably the main hosts of water in the lower mantle. Therefore, constraints on the single-crystal elastic tensor of δ-(Al,Fe)OOH solid solutions are crucial to quantify the elastic anisotropy of this material, and advance the current understanding of the recycling of water into the lower mantle. Yet, experimental data for intermediate compositions are scarce, limiting the understanding of how Fe incorporation affects the single-crystal elastic properties of δ-AlOOH. In this study, we provide experimental constraints on the single-crystal elasticity of two δ-(Al,Fe)OOH solid solutions, with Fe/(Al + Fe) of 0.06(1) and 0.133(3). Large single-crystal samples of δ-(Al,Fe)OOH were synthetized at high pressures and temperatures using a multi-anvil press, and the full elastic stiffness tensors were determined at ambient conditions by combining X-ray diffraction and Brillouin scattering measurements. We show that replacing Al3+ with Fe3+ in δ-(Al,Fe)OOH lowers the magnitude of most coefficients of the elastic stiffness tensor (cij), which translates into a substantial reduction of aggregate moduli and acoustic wave velocities. We further show that, at ambient conditions, the acoustic anisotropy of δ-(Al,Fe)OOH displays no sensitivity to Fe–Al substitution. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0031-9201 361 2025 Effect of chemistry on the compressibility and high-pressure structural evolution of the CaFe2O4-type aluminous silicate phase 107331 EN Giacomo Criniti Bayerisches Geoinstitut, University of Bayreuth Tiziana Boffa Ballaran Bayerisches Geoinstitut, University of Bayreuth Alexander Kurnosov Bayerisches Geoinstitut, University of Bayreuth Takayuki Ishii Institute for Planetary Materials, Okayama University Elena-Marie Rogmann Bayerisches Geoinstitut, University of Bayreuth Konstantin Glazyrin Deutsches Elektronen-Synchrotron DESY Timofey Fedotenko Deutsches Elektronen-Synchrotron DESY Daniel J. Frost Bayerisches Geoinstitut, University of Bayreuth Approximately 22–26 vol% of a basaltic phase assemblage at lower mantle conditions is comprised of a (Na,Mg,Fe2+)(Al,Si,Fe3+)2O4 phase with CaFe2O4-type (CF-type) structure. Previous experimental studies attempted to determine the equation of state of the CF-type phase but reported contrasting compressibility values, even for samples with the same composition. Therefore, the elastic properties of the CF-type phase remain, to date, largely unconstrained. Here, we conducted single-crystal X-ray diffraction (SCXRD) measurements in the diamond anvil cell (DAC) at high pressure and room temperature on three samples of CF-type phase with compositions Na0.90(1)Al1.03(2)Si1.00(2)O4 (NaCF), Na0.66(4)Mg0.28(4)Al1.22(3)Si0.78(3)O4 (MgCF) and Na0.62(2)Mg0.19(1)Fe2+0.17(1)Fe3+0.080(4)Al1.20(3)Si0.70(1)O4 (FeCF). A multi-sample loading approach was employed for most DAC runs, where two samples were loaded in the same sample chamber to reduce possible systematic deviations between datasets, thus enhancing internal consistency and corroborating data reproducibility. Experiments on the NaCF and MgCF samples were conducted up to ∼50 GPa, while the FeCF sample was compressed to ∼72 GPa to better characterize the effect of the spin crossover of octahedrally coordinated Fe3+. We found the isothermal bulk modulus (KT0) to increase with decreasing NaAlSiO4 content, accompanied by only a slight decrease in its pressure derivative (K'T0). Analysis of the crystal structures of the three samples at high pressure allowed compositional trends to be determined also for the interatomic bonds and polyhedral compressibility, as well as the distortion indices. These suggest an overall stiffening of the A site with increasing Mg2+ and Fe2+ content, as well of the two B sites with increasing Al3+ and Fe3+ content. Enhanced compressibility of the unit cell and octahedral B sites was observed between ∼26–42 GPa in the FeCF sample, suggesting a pressure-induced spin crossover of Fe3+, in agreement with some previous observations. Finally, trends in the elastic properties from experimental studies conducted along the NaAlSiO4-MgAl2O4 join are discussed and used as a proxy to evaluate the reliability of end-member properties for the CF-type phase employed in most recent mineral physical and thermodynamic databases. Our analysis suggests current mineral physical models might underestimate densities and overestimate bulk sound velocities of NaAlSiO4-rich CF-type phases with basaltic composition. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1948-7185 16 23 2025 Ultrafast Protein Dynamics Prior to Retinal Photoisomerization in Microbial Rhodopsins 5732 5738 EN Shinya Tahara Molecular Spectroscopy Laboratory, RIKEN Rika Kurihara Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Keiichi Kojima Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hikaru Kuramochi Molecular Spectroscopy Laboratory, RIKEN Satoshi Takeuchi Molecular Spectroscopy Laboratory, RIKEN Yuki Sudo Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tahei Tahara Molecular Spectroscopy Laboratory, RIKEN Rhodopsins, an important group of photoreceptor proteins, possess a retinal chromophore. It has long been believed that the photoisomerization of the chromophore is the initial event triggering its photocycle. However, we recently reported that protein structural changes around the chromophore precede photoisomerization in bacteriorhodopsin (BR). In this study, we performed deep-ultraviolet femtosecond stimulated Raman measurements for H+-pump rhodopsin (RxR) and photosensor rhodopsin (NpSRII) to investigate whether these ultrafast protein dynamics are common among rhodopsins. We observed that the protein structural changes occur within 0.2 ps after photoexcitation and precede the chromophore photoisomerization, similar to the case for BR. This strongly indicates that the protein structural change precedes the photoisomerization in rhodopsins, regardless of the difference in their origins and functions. Furthermore, we found that only limited protein changes occur on the time scale of the photoisomerization, suggesting that the protein environment is already optimized for the structural change of the chromophore. These observations raise the possibility that the ultrafast protein change arranges the environment around the chromophore to facilitate the photoisomerization. No potential conflict of interest relevant to this article was reported.

American Physical Society (APS) Acta Medica Okayama 0031-9007 134 24 2025 Acceleration of Positive Muons by a Radio-Frequency Cavity 245001 EN S. Aritome Graduate School of Science, University of Tokyo K. Futatsukawa High Energy Accelerator Research Organization H. Hara Research Institute for Interdisciplinary Science, Okayama University K. Hayasaka Institute of Science and Technology, Niigata University Y. Ibaraki Graduate School of Science, Nagoya University T. Ichikawa Graduate School of Science, Nagoya University T. Iijima Graduate School of Science, Nagoya University H. Iinuma Graduate School of Science and Engineering, Ibaraki University Y. Ikedo High Energy Accelerator Research Organization Y. Imai Research Institute for Interdisciplinary Science, Okayama University K. Inami Graduate School of Science, Nagoya University K. Ishida High Energy Accelerator Research Organization S. Kamal Department of Chemistry, Laboratory for Advanced Spectroscopy and Imaging Research (LASIR), University of British Columbia S. Kamioka High Energy Accelerator Research Organization N. Kawamura High Energy Accelerator Research Organization M. Kimura High Energy Accelerator Research Organization A. Koda High Energy Accelerator Research Organization S. Koji Graduate School of Science, Nagoya University K. Kojima Kobayashi-Maskawa Institute for the Origin of Particles and the Universe, Nagoya University A. Kondo Graduate School of Science, Nagoya University Y. Kondo Japan Atomic Energy Agency (JAEA) M. Kuzuba Graduate School of Science and Engineering, Ibaraki University R. Matsushita Graduate School of Science, University of Tokyo T. Mibe High Energy Accelerator Research Organization Y. Miyamoto Research Institute for Interdisciplinary Science, Okayama University J. G. Nakamura High Energy Accelerator Research Organization Y. Nakazawa Graduate School of Science and Engineering, Ibaraki University S. Ogawa Research Center of Advanced Particle Physics, Kyushu University Y. Okazaki High Energy Accelerator Research Organization A. Olin Department of Physics and Astronomy, University of Victoria M. Otani High Energy Accelerator Research Organization S. Oyama Graduate School of Science, University of Tokyo N. Saito High Energy Accelerator Research Organization H. Sato Graduate School of Science and Engineering, Ibaraki University T. Sato Graduate School of Science, University of Tokyo Y. Sato Institute of Science and Technology, Niigata University K. Shimomura High Energy Accelerator Research Organization Z. Shioya Faculty of Science, Kyushu University P. Strasser High Energy Accelerator Research Organization S. Sugiyama Graduate School of Science, Nagoya University K. Sumi Graduate School of Science, Nagoya University K. Suzuki Kobayashi-Maskawa Institute for the Origin of Particles and the Universe, Nagoya University Y. Takeuchi Faculty of Science, Kyushu University M. Tanida Faculty of Science, Kyushu University J. Tojo Faculty of Science, Kyushu University K. Ueda Graduate School of Science, Nagoya University, Nagoya S. Uetake Research Institute for Interdisciplinary Science, Okayama University X. H. Xie School of Physics, Peking University M. Yamada Faculty of Science, Kyushu University S. Yamamoto Research Institute for Interdisciplinary Science, Okayama University T. Yamazaki High Energy Accelerator Research Organization K. Yamura Institute of Science and Technology, Niigata University M. Yoshida High Energy Accelerator Research Organization T. Yoshioka Research Center of Advanced Particle Physics, Kyushu University M. Yotsuzuka Graduate School of Science, Nagoya University Acceleration of positive muons from thermal energy to 100 keV has been demonstrated. Thermal muons were generated by resonant multiphoton ionization of muonium atoms emitted from a sheet of laser-ablated aerogel. The thermal muons were first electrostatically accelerated to 5.7 keV, followed by further acceleration to 100 keV using a radio-frequency quadrupole with an intensity of 2×10－3 𝜇+/pulse. The transverse normalized rms emittance of the accelerated muons in the horizontal and vertical planes were 0.85±0.25⁢(s⁢t⁢a⁢t)+0.22－0.13⁢(syst) ⁢𝜋 mm mrad and 0.32±0.03⁢(stat)+0.05－0.02⁢(syst) 𝜋 mm mrad, respectively. The measured emittance values demonstrated phase-space reduction by a factor of 2.0 ×102 (horizontal) and 4.1 ×102 (vertical) allowing good acceleration efficiency. These results pave the way to realize the first-ever muon accelerator for a variety of applications in particle physics, material science, and other fields. 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.

Elsevier BV Acta Medica Okayama 0021-9258 301 3 2025 Taste receptor type 1 member 3 in osteoclasts regulates osteoclastogenesis via detection of glucose 108273 EN Anna Yoshimura Division of Molecular Signaling and Biochemistry, Kyushu Dental University Takuma Matsubara Division of Molecular Signaling and Biochemistry, Kyushu Dental University Nao Kodama Division of Molecular Signaling and Biochemistry, Kyushu Dental University Yoshimitsu Kakuta Laboratory of Structural Biology, Graduate School of Systems Life Sciences, Kyushu University Kazuma Yasuda Division of Molecular Signaling and Biochemistry, Kyushu Dental University Ryusuke Yoshida Department of Oral Physiology, Graduate School of Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Osamu Kaminuma Department of Disease Model, Research Institute of Radiation Biology and Medicine, Hiroshima University Shuhei Hosomi Department of Gastroenterology, Graduate School of Medicine, Osaka Metropolitan University Hiroji Shinkawa Department of Hepatobiliary-Pancreatic Surgery, Graduate School of Medicine, Osaka Metropolitan University Quan Yuan State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University Tatsuo Kawamoto Division of Orofacial Functions and Orthodontics, Kyushu Dental University Shoichiro Kokabu Division of Molecular Signaling and Biochemistry, Kyushu Dental University The taste system extends beyond the oral cavity, with various taste receptors found in extraoral organs. Mice deficient in the taste receptor type 1 (TAS1R) family member, TAS1R3, and fed a high-fat, high-sugar diet showed high bone mass without altering food consumption. However, the underlying mechanisms, including the cell types responsible for TAS1R3 expression, remain unclear. Here, we demonstrate the expression and function of TAS1R3 in osteoclasts, which are responsible for bone resorption. The expression of Tas1r3, but not Tas1r1 or Tas1r2, is evoked during osteoclast differentiation. Osteoclastogenesis-related genes were downregulated in TAS1R3-deficient mice, whereas the opposite phenotypes were elicited by TAS1R3 overexpression. Contrary to the common heterodimerization with TAS1R1 or TAS1R2, TAS1R3 formed a homodimer that functioned to detect glucose, enhance p38 phosphorylation, and induce osteoclastogenesis. These results provide novel insights into the role of TAS1R3 in bone metabolism and suggest that TAS1R3 may be a viable target for therapeutic agents in bone metabolic diseases. 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.

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.

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.

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.

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.

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.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1463-9076 2026 Phase behaviour of liquid CO2 with an impurity of water: influence of CO2 hydrate EN Hideki Tanaka Research Institute for Interdisciplinary Science, Okayama University Masakazu Matsumoto Research Institute for Interdisciplinary Science, Okayama University Takuma Yagasaki Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University Munetaka Takeuchi Engineering Advancement Association of Japan Yoshihito Mori Ochanomizu University Takumi Kono Engineering Advancement Association of Japan The solubility of water in liquid CO2 coexisting with CO2 hydrate or liquid water is evaluated in order to investigate the thermodynamic conditions to avoid the formation of CO2 hydrate in the transportation processes of liquid CO2. To this end, theoretical calculations have been carried out to obtain the chemical potentials of water and CO2 in all the phases involved in their coexistence. The solubility of water in liquid CO2 coexisting with liquid water decreases with decreasing temperature over a wide range of temperature and pressure, except for in the vicinity of the critical point of CO2. The decrease in the solubility is further enhanced by the formation of hydrate. We estimate the Gibbs energy of hydrate formation, which is an important property for sequestration of CO2, for cases where the temperature or pressure of water-saturated liquid CO2 decreases. We also estimate the amount of water precipitated as hydrate during these processes, which has a direct bearing on flow assurance in CO2 transportation. The present study will contribute to the development of a low-energy, safe CO2 transport network aiming at achieving large-scale carbon neutrality. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2052-4129 13 11 2026 Photoinduced sulfanyloximation of styrenes using N-nitrosamines and thiols 3367 3375 EN Ken Yamazaki Division of Applied Chemistry, Okayama University Toshiki Tamura Division of Applied Chemistry, Okayama University Shuta Akimoto Division of Applied Chemistry, Okayama University Tomoya Miura Division of Applied Chemistry, Okayama University Molecules featuring both sulfur and nitrogen atoms are privileged scaffolds in medicinal chemistry and biological systems. However, methods for the direct and regioselective installation of these heteroatoms onto alkenes remain limited. Herein, we report a visible-light-induced, three-component sulfanyloximation of styrenes utilizing thiols and N-nitrosamine as a bench-stable nitrogen oxide (NO) surrogate. This regioselective protocol operates under mild conditions with remarkable functional group tolerance. The synthetic utility of this methodology is further demonstrated by its extension to the synthesis of 2,3-disubstituted indoles and the divergent downstream derivatization of α-sulfanyl ketoxime products via imidoyl fluoride intermediates. An extensive mechanistic investigation supports a pathway initiated by thiyl radical addition to alkenes followed by radical coupling with in situ generated NO. 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.

AIP Publishing Acta Medica Okayama 2468-2047 11 1 2025 Pressure calibrations of high-pressure large-volume presses at HPSTAR 017803 EN Yongjiang Xu Center for High Pressure Science and Technology Advanced Research Peiyan Wu Center for High Pressure Science and Technology Advanced Research Sheng Shang Center for High Pressure Science and Technology Advanced Research Xue Wang Center for High Pressure Science and Technology Advanced Research Taihang Li Center for High Pressure Science and Technology Advanced Research Shuchang Gao Center for High Pressure Science and Technology Advanced Research Shijie Lv Center for High Pressure Science and Technology Advanced Research Hang Cheng Center for High Pressure Science and Technology Advanced Research Qianzhi Xu Center for High Pressure Science and Technology Advanced Research Shang Lei Center for High Pressure Science and Technology Advanced Research Jiajia Feng Center for High Pressure Science and Technology Advanced Research Lei Zhao Center for High Pressure Science and Technology Advanced Research Wim van Westrenen Center for High Pressure Science and Technology Advanced Research Takayuki Ishii Institute for Planetary Materials, Okayama University Bin Chen Center for High Pressure Science and Technology Advanced Research Lei Su Center for High Pressure Science and Technology Advanced Research Yang Ding Center for High Pressure Science and Technology Advanced Research Wenge Yang Center for High Pressure Science and Technology Advanced Research Ho-Kwang Mao Center for High Pressure Science and Technology Advanced Research Yanhao Lin Center for High Pressure Science and Technology Advanced Research Large-volume presses (LVPs) are widely utilized in diverse research fields―including high-pressure physics, chemistry, materials science, and Earth and planetary sciences―to investigate the physical and chemical properties of materials under extreme high-pressure and high-temperature conditions. A prerequisite for achieving reproducible property measurements is the determination and control of pressure within experimental setups. However, the lack of precise pressure calibration in LVPs hinders the broader application of such devices in ultrahigh-pressure studies. This study employs a suite of standard phase transition-based pressure markers―comprising metallic conductors, semiconductors, and minerals―through both in situ and ex situ identification approaches, to establish pressure calibration curves ranging from 0.4 to >30 GPa for various types of LVP installed at the Center for High Pressure Science and Technology Advanced Research (HPSTAR), Beijing, including piston–cylinder, cubic, and multi-anvil presses. The results provide a unified and traceable pressure reference for high-pressure experiments conducted at HPSTAR, while also offering technical guidance and calibration standards for other researchers utilizing similar LVP systems, thereby enabling more consistent comparison between different laboratories. This work facilitates the advancement of LVP research toward broader applications in higher-pressure regimes. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0342-1791 53 2 2026 High-pressure spectroscopic investigation of ε-FeOOH: toward a better understanding of pressure-induced hydrogen-bond symmetrization 18 EN Izumi Mashino Institute for Planetary Materials, Okayama University Shigeru Yamashita Institute for Planetary Materials, Okayama University Takashi Yoshino Institute for Planetary Materials, Okayama University High-pressure spectroscopic measurements of ε-FeOOH were conducted up to ~ 65 GPa at room temperature in diamond anvil cells. The pressure evolution of the Raman vibrational modes confirms that a hydrogen-bond-symmetrization-induced phase transition from P21nm to Pnnm occurs at ~ 18 GPa. Infrared (IR) spectroscopic measurements suggest that the Pnnm phase has a disordered hydrogen state, and no spectroscopic evidence for fully centered hydrogen bonds is observed within the investigated pressure range. Above ~ 45 GPa, Fe3+ in ε-FeOOH undergoes a high-spin to low-spin transition as indicated by a reduction of the unit cell volume, together with reductions in IR transmitted and Raman signals. These results demonstrate that ε‑FeOOH preserves a disordered hydrogen‑bond configuration up to at least 45 GPa, whereas δ-AlOOH transforms to a centered hydrogen-bond configuration at ~ 18 GPa. This compositional contrast suggests that Fe‑bearing oxyhydroxides follow a distinct evolution of hydrogen bonding under compression, providing insight into hydrogen behavior in deep Earth materials. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0021-9258 302 6 2026 A photoactivatable Cre-loxP system for spatiotemporal genetic manipulation in mouse taste buds 113085 EN Yu Zuo Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kengo Horie Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yoshihiro Mitoh Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yasuhiro Yamada Department of Molecular Pathology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo Tomoka Takao Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takeshi Takarada Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shoichiro Kokabu Division of Biochemistry, Kyushu Dental University Ryusuke Yoshida Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Conventional genetic approaches, including global gene KO and conditional KO strategies such as the Cre-loxP system, have some limitations arising from systemic effects or insufficient temporal resolution. The recently developed photoactivatable Cre (PA-Cre) system may have a potential to improve spatiotemporal control of gene manipulation. In this study, we established and validated the feasibility of the PA-Cre system using taste buds as a model. We generated TRE-PA-Cre:R26-rtTA/tdTomato mice to evaluate blue-light-induced Cre recombinase activity. Through systematic optimization of illumination parameters, we found that a single session of blue-light-illumination resulted in limited recombination efficiency, whereas a multisession illumination strategy markedly increased recombination efficiency. To further assess the utility of the PA-Cre system for gene KO, we generated TRE-PA-Cre:R26-rtTA:Tas1r3-flox mice and targeted a taste-related gene Tas1r3. Genomic DNA quantitative PCR and reverse transcription-quantitative PCR both showed partial reductions in Tas1r3 at the DNA and mRNA levels, respectively. Behavioral assays further revealed a selective decrease in sensitivity to sweet and umami stimuli. Together, these findings demonstrate PA-Cre-mediated gene manipulation in taste buds and establish a practical optical activation paradigm, providing a high-spatiotemporal-resolution tool for investigating gene function in optically targeted regions. 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.

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.

Elsevier BV Acta Medica Okayama 8756-3282 209 2026 PPy-coated wire actuators for micromechanostimulation of cells – identification of immediate-early responsive mechanoregulatory genes in osteoblasts 117914 EN Jiamin Chen Department of Orthodontics, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Amaia B. Ortega-Santos Department of Physics, Chemistry and Biology (IFM), Linköping University Satoru Hayano Department of Orthodontics, Okayama University Hospital Ziyi Wang Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Jose G. Martinez Department of Physics, Chemistry and Biology (IFM), Linköping University Emilio Satoshi Hara Department of Advanced International and Information Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Edwin W.H. Jager Department of Physics, Chemistry and Biology (IFM), Linköping University Hiroshi Kamioka Department of Orthodontics, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Mechanotransduction, i.e., the conversion of mechanical cues into biochemical signals, is essential for bone development, remodeling, and adaptation. Although mechanical loading is known to regulate osteoblast function and bone homeostasis, dissecting the early and sustained mechanotransductive responses at the microscale remains challenging due to limitations of existing in vitro models. Here, we report the development and application of a mechanostimulation system comprising a polypyrrole (PPy)-based wire actuator that expands and contracts (4 μm in radius) upon electrical actuation and enables precise, localized micromechanical stimulation of a small number of cells within standard culture formats. Using this system, we applied short-term (30 min) cyclic (Cyc30) or static (Stat30), as well as prolonged (120 min) cyclic (Cyc120) stimulations to two osteoblast-like cells (MC3T3-E1 or KUSA-A1). Subsequent transcriptomic profiling and computational network analyses revealed that Cyc30 was not capable of inducing significant changes in mRNA expression, suggesting cellular adaptation to short-term cyclic loading. In contrast, Stat30 induced the upregulation of Fos, Btg2, Egr1, and Fosl1, all known genes associated with mechanotransduction, supporting the validity and reproducibility of our experimental mechanostimulation system. Notably, two long non-coding RNAs (B930036N10Rik and 5430431A17Rik) were identified for the first time as being upregulated in response to Stat30 stimuli. Among the differentially expressed genes (DEGs) upregulated by Cyc120 stimuli, Hmox1, a stress-inducible enzyme known for its roles in maintaining cellular homeostasis and promoting survival, was the only DEG repeatedly observed across the Cyc30/Cyc120 and Stat30/Cyc120 comparisons in both cell types, potentially emerging as a key stress-response gene under prolonged mechanical loading. Collectively, these results establish the PPy-based microactuator as a powerful tool for microscale mechanobiology, and provide molecular insight into immediate-early responsive transcriptional programs underlying osteoblastic mechanoadaptation conserved across different cell types. 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.

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.

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 0304-4203 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.

Ceramic Society of Japan Acta Medica Okayama 1348-6535 134 4 2026 Cation distribution and diffusion-path topologies of A-site-deficient perovskite LixLa(1－x)/3NbO3 225 231 EN Naoto Kitamura Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science Yizhong Tang Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science Koji Kimura Department of Physical Science and Engineering, Nagoya Institute of Technology Ippei Obayashi Center for Artificial Intelligence and Mathematical Data Science, Okayama University Yohei Onodera Center for Basic Research on Materials, National Institute for Materials Science Ken Nakashima Faculty of Materials for Energy, Shimane University Chiaki Ishibashi Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science Yasushi Idemoto Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science Koichi Hayashi Department of Physical Science and Engineering, Nagoya Institute of Technology LixLa(1－x)/3NbO3 with an A-site-deficient perovskite structure was investigated with a focus on the relationship between its atomic configuration and Li+ diffusion properties. To this end, total scattering (diffraction) measurements were performed, and then reverse Monte Carlo modeling using the data was employed to construct the atomic configuration. The results suggest that the partial occupancy of La in the La-poor layer facilitate Li+ diffusion across the layer owing to the volume contraction. Furthermore, topological analyses conducted via persistent homology using the constructed atomic configuration indicate that a large fourfold ring formed by Nb and O is one of the reasons for superior Li+ diffusion in LixLa(1－x)/3NbO3. 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.

Wiley Acta Medica Okayama 2196-0216 13 8 2026 Electrochemical Synthesis of Benzo[b]Phosphole Oxides via Dehydrogenative Annulation Using 1,4-Diazabicyclo [2.2.2]Octane as a Mediator e70175 EN Koichi Mitsudo Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Sakura Kinjo Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yasuyuki Okumura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Eisuke Sato Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Riki Kato Research Institute for Interdisciplinary Science, Okayama University Yuta Nishina Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Seiji Suga Graduate School of Environmental, Life, Natural Science and Technology, Okayama University The electrochemical intermolecular annulation of diarylphosphine oxides with alkynes for the synthesis of benzo[b]phosphole oxides has been reported. The reaction proceeded under transition-metal- and oxidant-free conditions via indirect electrolysis, using 1,4-diazabicyclo[2.2.2]octane as a mediator. High-surface-area carbon electrodes, such as carbon felt and reticulated vitreous carbon, are essential for this reaction. Several diarylphosphine oxides and alkynes were applied to electrochemical annulation, and the corresponding benzo[b]phosphole oxides were obtained. Mechanistic studies suggested that the reaction proceeds via radical intermediates generated through multiple pathways. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-7345 2026 Synthesis of sulfur- and oxygen-bridged cationic [4]-helicenes mediated by Friedel–Crafts-S N Ar tandem reactions for red-light-driven organophotoredox catalysis EN Ryoga Hasebe Graduate School of Environment and Information Sciences, Yokohama National University Rumi Hanada Graduate School of Environment and Information Sciences, Yokohama National University Yuta Tanaka Graduate School of Environment and Information Sciences, Yokohama National University Yuta Goto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Mio Takeuchi Graduate School of Environment and Information Sciences, Yokohama National 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 Research Institute for Interdisciplinary Science, Okayama University Yujiro Hoshino Graduate School of Environment and Information Sciences, Yokohama National University The synthesis of sulfur- and oxygen-bridged cationic [4]-helicenes via a tandem Friedel–Crafts–SNAr reaction of a diaryl sulfide or a diaryl ether with a (thio)salicylic acid has been developed. The sulfur-bridged cationic [4]-helicenes are suitable as catalysts for photoredox reactions under low-energy light sources such as red LED light. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1434-193X 2026 Informatics‐Driven and Automated Optimization in Flow Electrochemical Synthesis e202501237 EN Eisuke Sato Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Akine Tani Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tomohiro Nakahama 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 Electrochemical synthesis has emerged as a powerful platform for environmentally sustainable chemical transformations. When integrated with flow chemistry, electrosynthetic processes exhibit enhanced scalability, making them suitable for industrial applications. Recently, the integration of electrochemical flow systems with informatics techniques has accelerated the optimization of reaction conditions. Data-driven strategies facilitate rapid exploration of multidimensional parameter spaces, enabling identification of optimal reaction conditions with high efficiency. These advances have enabled the development of automated optimization systems. This review highlights recent progress in combining electrosynthesis, flow chemistry, and computational tools, focusing on representative examples that illustrate efficient optimization protocols and autonomous reaction development. By showcasing these developments, we discuss how the integration of these technologies is driving innovation in electrochemical synthesis. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0040-4039 179 2026 Visible-light-induced photocatalytic intermolecular cyclization for synthesis of 2,2-diarylchromanes 156034 EN Sakura Kodaki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Momo Kondo Laboratory of Biopharmaceutics, Faculty of Pharmaceutical Sciences, Tokyo University of Science Junta Minato Laboratory of Cellular Drug Discovery and Development, Faculty of Pharmaceutical Sciences, Tokyo University of Science Shoko Itakura Laboratory of Biopharmaceutics, Faculty of Pharmaceutical Sciences, Tokyo University of Science Hiroyoshi Takamura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Makiya Nishikawa Laboratory of Biopharmaceutics, Faculty of Pharmaceutical Sciences, Tokyo University of Science Isao Kadota Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kosuke Kusamori Laboratory of Cellular Drug Discovery and Development, Faculty of Pharmaceutical Sciences, Tokyo University of Science Kenta Tanaka Research Institute for Interdisciplinary Science, Okayama University The photocatalytic cyclization of salicylaldehydes with 1,1-diarylalkenes for the synthesis of 2,2-diarylchromanes has been developed. The catalytic amount of Ir photocatalyst proceeds the cyclization to give the various 2,2-diaryl chromanes under irradiation with blue LEDs. The obtained 2,2-diarylchromanes exhibit noticeable free-radical-scavenging activities, which have been largely unexplored. Notably, the chromane can convert to 2,2-diaryl-2H-naphtho[1,2-b]pyran bearing strong electron withdrawing groups, which are found in various photochromic materials. Thus, the present reaction constitutes a promising tool for the synthesis of functional materials and biologically active compounds. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2211-7156 25 2026 Peptide nanomicelles for NIR light-dependent siRNA delivery 103265 EN Taufik Fatwa Nur Hakim Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mizuki Kitamatsu Department of Applied Chemistry, Kindai University Shoumu Fujimoto Department of Applied Chemistry, Kindai University Kazunori Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University The peptide amphiphile PA8, derived from the GAVILRR peptide, was developed as a carrier for small interfering RNA (siRNA) delivery; however, its RNA interference (RNAi) efficacy was limited owing to predominant endocytotic uptake. In this study, the RNAi efficiency of PA8 nanomicelle/siRNA complexes was enhanced by modifying the nanomicelles with the photosensitizer DY750 and the tumor-homing peptide iRGD. The conjugation of DY750 to the nanomicelles facilitated endosomal escape of the nanomicelle/siRNA complexes, enabling the cytosolic release of siRNA. Additionally, the incorporation of iRGD improved RNAi delivery efficiency in the AsPC-1 pancreatic ductal adenocarcinoma cell line. PA8-DY750-iRGD nanomicelle complexes loaded with siRNA against polo-like kinase 1 (PLK1) achieved an 80% reduction in PLK1 mRNA levels in AsPC-1 cells and a moderate 28% knockdown in NCI-N87 gastric cancer cells. Notably, no RNAi effect was observed in noncancerous 1C3D3 pancreatic cells or HEK293T kidney cells, underscoring the selectivity of this system for AsPC-1 cells. These findings highlight the potential of PA8-DY750-iRGD nanomicelle complexes as a targeted therapeutic platform for specific cancers, particularly pancreatic cancer. 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 Liquid–liquid phase separation by caged coacervating peptides 10464 EN Akinari Bando Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mizuki Kitamatsu Department of Applied Chemistry, Kindai University Yuuki Kanazaki Department of Applied Chemistry, Kindai University Rika Tojo Department of Applied Chemistry, Kindai University Kazunori Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Liquid–liquid phase separation is an important biomolecular process in the formation of membraneless intracellular organelles that has inspired the development of artificial droplet systems. We developed caged coacervating peptides (CCPs) based on a histidine-rich squid beak protein sequence. The peptides were caged with a photodeprotectable (7-diethylaminocoumarin-4-yl)methoxycarbonyl group. The CCPs formed coacervates in the caged state and were partially dispersed upon blue-light irradiation. Photo-uncaging occurred rapidly, inducing coacervate dispersion. A mutant CCP with reduced π–π interactions exhibited efficient photo-dependent disassembly and enabled the encapsulation and release of a fluorescently labeled adenosine 5′-triphosphate (Bodipy-ATP) upon irradiation. These CCPs offer an efficient light-controlled approach for biomolecular encapsulation within coacervates and targeted drug delivery. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0143-4160 135 2026 Regulation of brain-specific kinases 1 and 2 (BRSK1/2) by Ca2+/calmodulin 103134 EN Naoyuki Washida Moe Kataoka Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Okayama University Anna R. Brun Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Uryu Takezaki Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Ko Hijikawa Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Okayama University Haruki Yamauchi Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Satomi Ohtsuka Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Masaki Magari Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Ryo Morishita CellFree Sciences Co., Ltd. Hiroshi Tokumitsu Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University We conducted a genome-wide calmodulin (CaM) interaction screening of 462 GST-fused human protein kinases to identify novel CaM-dependent protein kinases (CaMKs). In addition to known CaMKs, including myosin light chain kinases, CaMK2γ, and death-associated kinase 2, we identified the brain-specific protein kinase 2 (BRSK2, also known as SAD-A) as a novel CaM interactant. Proximity biotinylation and CaM–sepharose chromatography assays revealed that rat BRSK isoforms (BRSK1/2) interact with CaM in a Ca2+-dependent manner in vitro. We found that CaM suppresses the activation-loop phosphorylation of BRSK1 (at Thr189) and BRSK2 (at Thr175) by liver kinase B1 (LKB1), an activating kinase, in a Ca2+-dependent manner (IC50 of ∼7 µM), thereby inhibiting BRSK activation. LKB1-catalyzed phosphorylation of the catalytic domain mutant of BRSK1 (residues 1–294) at Thr189 was suppressed by the addition of Ca2+/CaM, consistent with direct CaM binding of the kinase domain, as well as wild-type BRSK1. We confirmed that the LKB1 activity was not directly suppressed by Ca2+/CaM, supporting the hypothesis that the direct interaction of Ca2+/CaM with the kinase domain blocks the phosphorylation/activation of BRSK1/2 by LKB1. The kinase activity and PP2Cα-catalyzed dephosphorylation of LKB1-phosphorylated BRSK1 were not altered by Ca2+/CaM, although it was demonstrated to bind to Ca2+/CaM like that of unphosphorylated BRSK1. This unrecognized mechanism of BRSK1/2 regulation, involving the direct role of Ca2+/CaM binding, which inhibits phosphorylation/activation by LKB1, may open a new Ca2+ signal transduction pathway in neurons. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2238-7854 42 2026 An electric field temporarily strengthens zirconia ceramics 1806 1810 EN Akira Kishimoto Faculty of Environmental, Life, Natural Science and Technology, Okayama University Takahiro Shimizu Faculty of Environmental, Life, Natural Science and Technology, Okayama University Mitsuru Nishiyama Faculty of Environmental, Life, Natural Science and Technology, Okayama University Shinya Kondo Faculty of Environmental, Life, Natural Science and Technology, Okayama University Takashi Teranishi Faculty of Environmental, Life, Natural Science and Technology, Okayama University By applying an electric field to yttria-stabilized zirconia (8YSZ) equipped with an inert electrode, oxide ions are localized near the positive electrode, causing it to expand. When polarization was performed under different conditions, it was possible to strengthen the material to 1.5 times that of an untreated sample. The lattice constant of the positive electrode surface after polarization was larger than before polarization. When the Vickers hardness of the positive electrode surface was measured by changing the test load, the smaller the load, the higher the hardness value. Polarization caused oxide ions to move near the positive electrode, filling in the defects and generating an expanded layer with a large lattice constant. It is believed that this was subjected to compressive stress from the bulk layer, which had not changed in volume, resulting in an increase in strength. No potential conflict of interest relevant to this article was reported.

一般社団法人粉体粉末冶金協会 Acta Medica Okayama 0532-8799 73 3 2026 熱間静水圧加圧法を用いたイットリア安定化ジルコニア緻密層の低温形成 55 59 EN Kyohei MANABE Osaka Gas Co. Ltd. Mitsuaki ECHIGO Osaka Gas Co. Ltd. Akira KISHIMOTO Institute of Academic and Research, Faculty of Environmental, Life, Natural Science and Technology, Okayama University The sintering conditions using hot isostatic press (HIP) of yttria-stabilized zirconia (YSZ) were investigated to obtain a dense YSZ layer at low sintering temperature such as 1000°C for an electrolyte of metal-supported solid oxide fuel cell. It was found that a dense YSZ pellet with relative density of 93% could be obtained under a sintering condition of 1000°C-10 hours with HIP in 195 MPa. On the other hand, in X-ray diffraction analysis of the dense YSZ pellet, peaks of the monoclinic phase were slightly detected in addition to peaks of the cubic phase. From energy dispersive X-ray spectroscopy analysis, a small amount of boron was detected in the dense YSZ pellet. It is considered that the YSZ crystalline phase transformation of cubic to monoclinic phase was occurred by the boron diffusion from the diffusion barrier coating of metal foil capsule used for the HIP. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1043-1802 37 3 2026 A Cysteine-Specific Cationization Strategy for Versatile Antibody Production against Intrinsically Disordered Proteins 580 589 EN Ryui Sakaguchi Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Ai Miyamoto Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Rikako Kutsuma Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takeru Mori Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Daichi Nakashima Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mirei Masui Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Tomoko Honjo Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Midori Futami Department of Bioscience, Faculty of Life Science, Okayama University of Science Mariko Morii Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Toshiyuki Oshiki Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Junichiro Futami Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Several autoantigens relevant to the immune system, especially those targeted by autoantibodies induced by antitumor responses, tend to be rich in disordered regions and are prone to aggregation. This inherent instability presents significant challenges for the production, purification, and analysis of autoantigens in laboratory settings. Cysteine-specific cationization can effectively solubilize and purify these challenging proteins, allowing the isolation of full-length water-soluble antigens in their denatured state. The purified antigens enable accurate multiplex autoantibody assays using a suspension Luminex bead array platform. However, well-validated positive control antibodies are essential to ensuring precise clinical diagnosis. In this study, we prepared and characterized a panel of control antibodies by immunizing rabbits with cysteine-specific S-cationized antigens. The resulting antibodies predominantly recognized linear epitopes and were highly effective as quality control reagents in autoantibody array assays. Additionally, these antibodies maintained their ability to bind to their native, unmodified intracellular counterparts, highlighting the usefulness of this approach for producing antibodies against intrinsically disordered proteins. Although a modest immune response against the S-cationized modification site was observed, it remained minimal and did not affect the usefulness of the antibodies for assay validation. We propose this versatile cysteine-specific cationization platform for managing unstable proteins rich in disordered regions, supporting antigen production for diagnostics, and antibody development for research and validation purposes. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 2688-4046 6 3 2026 PPy‐Coated Wire Actuators for the Micromechanostimulation of Cells: Fabrication and Characterization e202500639 EN Amaia B. Ortega‐Santos Sensor and Actuator Systems, Department of Physics Chemistry and Biology (IFM), Linköping University Satoru Hayano Department of Orthodontics, Okayama University Hospital Emilio Satoshi Hara Advanced Research Center for Oral and Craniofacial Sciences Dental School, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Jose G. Martínez Sensor and Actuator Systems, Department of Physics Chemistry and Biology (IFM), Linköping University Hiroshi Kamioka Department of Orthodontics, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Edwin W. H. Jager Sensor and Actuator Systems, Department of Physics Chemistry and Biology (IFM), Linköping University Cellular mechanotransduction signals play a crucial role in physiological and pathological conditions, including skeletal disorders. Although various systems exist to mechanically stimulate cultured cells, most are constrained by incubator incompatibility, limited physiological relevance, nonuniform stimulation, or complexity. The objective of this article is to develop and validate a compact, incubator-compatible tool capable of delivering localized and physiologically relevant mechanical stimulation to small cell populations. Here, we introduce a polypyrrole-based wire-shaped microactuator designed to induce localized mechanical stress to adjacent cells. These wire-shaped microactuators are biocompatible, easy-to-use, and compact for use within standard in vitro cell culture systems. Using a noncontact optical method, we characterize the actuation of polypyrrole-coated wires in an aqueous NaDBS electrolyte, showing radial expansion of 1.5–8 µm depending on the deposited polypyrrole film thickness, comparable to cellular dimensions. Next, the actuation is confirmed to be robust and stable to use in cell culture media at physiological temperature. To evaluate biological relevance, osteoblastic KUSA-A1 cells are mechanically stimulated inside the incubator and transcriptomic changes are assessed. Mechanical stimulation resulted in upregulation of genes previously associated with mechanotransduction, including Fos and Fosb. Additionally, several uncharacterized long noncoding RNAs are differentially expressed, suggesting potential novel players in the mechanotransduction pathway. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2211-7156 18 2025 Development of FTase inhibitors inspired by the structures of andrastins 102828 EN Fumino Kitamura Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Masaru Tanioka Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Ayano Kosaka Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Nao Matsuzawa Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Takayuki Obita Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Yuko Sakajiri Tomokazu Shibata Department of Complex Systems Science, Graduate School of Informatics, Nagoya University Ryusuke Sawada Department of Pharmacology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Takeshi Yokoyama Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Aki Kohyama Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Tsuyoshi Yamada Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Yoshihiro Yamanishi Department of Complex Systems Science, Graduate School of Informatics, Nagoya University Mineyuki Mizuguchi Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Yuji Matsuya Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama We designed and synthesized structurally simple farnesyl transferase (FTase) inhibitors (1a–1d) by leveraging andrastin, a natural product with FTase inhibitory activity. 1a–1d possess a cyclopentane-1,3-dione core, which is critical for FTase recognition; a farnesyl moiety, which is a simplified motif of A to C rings of andrastin; and a carboxylic acid or methoxycarbonyl group, which enables multipoint hydrogen bonding interactions with FTase. Competitive inhibition experiments revealed that 1d has the most potent FTase inhibitory activity. Docking simulation analysis of 1a–1d with FTase suggested that the multipoint hydrogen bonding interactions between the cyclopentane-1,3-dione moiety and the carboxyl group play an important role in FTase recognition. No potential conflict of interest relevant to this article was reported.

JMIR Publications Inc. Acta Medica Okayama 2369-3762 12 2026 Prescription Support Practice for Pharmacy Students: Pre-Post Educational Intervention Study e79545 EN Fuka Aizawa Clinical Research Center for Developmental Therapeutics, Tokushima University Hospital Kenta Yagi Department of Clinical Pharmacology and Therapeutics, Graduate School of Biomedical Sciences, Tokushima University Tsukasa Higashionna Department of Pharmacy, Okayama University Hospital Hirofumi Hamano Department of Pharmacy, Okayama University Hospital Shimon Takahashi Department of Clinical Pharmacology and Therapeutics, Graduate School of Biomedical Sciences, Tokushima University Yoshito Zamami Department of Pharmacy, Okayama University Hospital Kazuaki Shinomiya Department of Pharmaceutical Care and Clinical Pharmacy, Tokushima Bunri University Takahiro Niimura Clinical Research Center for Developmental Therapeutics, Tokushima University Hospital Mitsuhiro Goda Department of Clinical Pharmacology and Therapeutics, Graduate School of Biomedical Sciences, Tokushima University Kei Kawada Department of Clinical Pharmacology and Therapeutics, Graduate School of Biomedical Sciences, Tokushima University Keisuke Ishizawa Clinical Research Center for Developmental Therapeutics, Tokushima University Hospital Background: In the field of team-based care, pharmacists are vital for optimizing medication therapy. However, many medical professionals lack the opportunity to learn how to propose prescription changes with precision. Objective: This study aimed to address this knowledge gap by developing and assessing a new educational program for pharmacy students focused on prescription support and interprofessional collaboration. Methods: We recruited 191 fifth-year pharmaceutical students during the 2022‐2024 academic years. The program featured a 7-day intensive curriculum that included learning how to assist with prescriptions, analyzing clinical data, and engaging in role-playing exercises. A web-based questionnaire and a paper test were used to evaluate students’ awareness and knowledge both before and after the program. Statistical analyses were performed to verify the significance of changes; we utilized the Wilcoxon signed-rank test for the ordinal data derived from the specific behavioral objectives and 2-tailed paired t tests for the interval data from the knowledge tests. The magnitude of change was quantified using r for Wilcoxon tests and Cohen dz for 2-tailed t tests, with 95% CI calculated to ensure the stability and reliability of the observed results. Results: Analysis of the primary outcome specific behavioral objectives revealed statistically significant effects across all items (Wilcoxon signed-rank test; P<.001). Effect sizes (r=0.505‐0.835) ranged from moderate to large, with particularly large effects observed in identifying contents issue (r=0.835, 95% CI 0.126-0.330; P<.001). Knowledge test scores showed significant improvement in the following 3 subjects: pharmacology (r=－0.504, 95% CI –0.215 to 0.127; P<.001), organic chemistry (r=0.254, 95% CI –0.148 to –0.193; P=.004), and communication (r=0.221, 95% CI –0.151 to –0.190; P=.01). No significant changes were observed in pathology or pharmacokinetics. Conclusions: This program provides strong evidence that practical, hands-on learning with hospital pharmacists helps improve pharmacy students’ professional skills and optimize pharmaceutical therapies in interprofessional care. By teaching pharmacists to effectively propose prescription changes, the program equips them to become integral members of interprofessional care, ultimately leading to optimized pharmaceutical care for patients. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0022-2623 69 5 2026 Discovery of Thermal Sensitizers That Inhibit Heat-Induced SAFB Granule Formation 5944 5955 EN Yuji Furutani Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Natsuki Shimasaki Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Riko Yamada Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Takashi Ohtsuki Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kazunori Watanabe Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University Hyperthermia is a minimally invasive cancer treatment based on heat stress-induced apoptosis. Its therapeutic efficacy, however, is often limited by tumor heterogeneity and acquired thermotolerance. Therefore, combination strategies involving hyperthermia and chemotherapy have been developed to enhance the therapeutic efficacy. Previously, we showed that SB366791 enhanced heat-induced apoptosis by inhibiting heat stress-induced scaffold attachment factor B (SAFB) granule formation, although its proapoptotic activity was insufficient. Therefore, we screened to identify novel compounds that enhance heat-induced apoptosis by suppressing SAFB granule formation. We identified four hit compounds that inhibited SAFB granule formation, all exhibiting thermal enhancement ratios > 1.0─that significantly enhanced heat-induced apoptosis efficiency. Additionally, the tumor volume in mice treated with a combination of Z19024498 and hyperthermia was significantly smaller than that in mice treated with hyperthermia or Z19024498. These results indicate that the identified compounds, specifically Z19024498, have potential as thermal sensitizers for hyperthermia therapy. No potential conflict of interest relevant to this article was reported.

The Carbon Society of Japan Acta Medica Okayama 2436-5831 4 3 2025 Synthesis and applications of porous carbonaceous materials with inherited molecular structural features from the precursor molecules 179 187 EN Koki Chida Institute of Multidisciplinary Research for Advanced Materials, Tohoku University Takeharu Yoshi Institute of Multidisciplinary Research for Advanced Materials, Tohoku University Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Kazuhide Kamiya Research Center for Solar Energy Chemistry, Graduate School of Engineering Science, The University of Osaka Ryota Sakamoto Department of Chemistry, Graduate School of Science, Tohoku University Fumito Tani Institute for Materials Chemistry and Engineering, Kyushu University Tomoki Ogoshi Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University Hirotomo Nishihara Institute of Multidisciplinary Research for Advanced Materials, Tohoku University The carbonization of organic crystalline materials, such as metal organic frameworks and covalent organic frameworks, has emerged as a promising approach for producing functional porous carbonaceous materials. However, both the chemically defined long-term ordered structures and the local chemical structures derived from these precursor materials are generally lost, resulting in amorphous carbons. As a result, controlling the molecular-level structure of nanoporous carbons remains a significant challenge. We report a new bottom-up synthesis approach for porous carbons with a molecular-level design, involving the carbonization of well-designed precursor molecules by thermal polymerization. Among the resulting carbons, ordered carbonaceous frameworks, which contain a high-density of regularly aligned single-atomic metal species, have been identified as promising platforms for single-atom catalysts. This approach also enables the synthesis of various three-dimensional porous carbons that reflect the structural features of their precursor molecules. Recent progress in the synthesis and applications of porous carbons derived from molecular precursors is summarized, highlighting their potential for the development of functional materials. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2041-6520 17 9 2026 Gaseous CO2 electrolysis: latest advances in electrode and electrolyzer technologies toward abating CO2 emissions 4363 EN Kazuhide Kamiya Research Center for Solar Energy Chemistry, Graduate School of Engineering Science, The University of Osaka Sora Nakasone Research Center for Solar Energy Chemistry, Graduate School of Engineering Science, The University of Osaka Ryo Kurihara Research Center for Solar Energy Chemistry, Graduate School of Engineering Science, The University of Osaka Asato Inoue Research Center for Solar Energy Chemistry, Graduate School of Engineering Science, The University of Osaka Hazuki Irie Research Center for Solar Energy Chemistry, Graduate School of Engineering Science, The University of Osaka Shoko Nakahata Research Center for Solar Energy Chemistry, Graduate School of Engineering Science, The University of Osaka Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Satoshi Taniguchi Research Institute for Chemical Process Technology, National Institute of Advanced Industrial Science and Technology (AIST), Central 5 Thuy T. H. Nguyen Research Institute for Chemical Process Technology, National Institute of Advanced Industrial Science and Technology (AIST), Central 5 Sho Kataoka Research Institute for Chemical Process Technology, National Institute of Advanced Industrial Science and Technology (AIST), Central 5 The conversion of CO2 into multicarbon (C2+) products via electrochemical reduction is considered a key technology for the sustainable production of fuels and chemicals. The performance of high-rate gaseous CO2 electrolysis is governed by interrelated factors such as the electrocatalysts, electrodes, electrolytes, and cell architectures. Despite the intensive focus on catalyst research, systematic studies addressing the other components remain scarce, leaving critical gaps in our understanding toward achieving higher performance in CO2 electrolysis systems. The nanoscale design of catalyst surface electronic structures and the macroscale design of electrodes and electrolyzer architectures both influence the overall activity of the electrochemical system. In designing macroscale components, it is necessary to establish benchmarks based on a comprehensive evaluation of CO2 emissions for the entire electrolysis process, because these parameters are directly linked to output metrics such as current density and cell voltage under practical operating conditions. This review summarizes recent advances in electrodes and electrolyzers, and through life-cycle assessment (LCA), evaluates key performance indicators (KPIs) for achieving negative emissions and assesses the current technology readiness of CO2 electrolysis. No potential conflict of interest relevant to this article was reported.

Proceedings of the National Academy of Sciences Acta Medica Okayama 0027-8424 123 6 2026 A nuclear CobW/WW-domain factor represses the CO2-concentrating mechanism in the green alga Chlamydomonas reinhardtii e2518136123 EN Daisuke Shimamura Graduate School of Biostudies, Division of Integrated Life Science, Kyoto University Junko Yasuda Graduate School of Biostudies, Division of Integrated Life Science, Kyoto University Yosuke Yamahara Graduate School of Biostudies, Division of Integrated Life Science, Kyoto University Hirobumi Nakano Graduate School of Biostudies, Division of Integrated Life Science, Kyoto University Shin-Ichiro Ozawa Institute of Plant Science and Resources, Okayama University Ryutaro Tokutsu Graduate School of Science, Division of Biological Sciences, Kyoto University Ayumi Yamagami Graduate School of Biostudies, Division of Integrated Life Science, Kyoto University Tomonao Matsushita Graduate School of Science, Division of Biological Sciences, Kyoto University Yuichiro Takahashi Research Institute for Interdisciplinary Science, Okayama University Takeshi Nakano Graduate School of Biostudies, Division of Integrated Life Science, Kyoto University Hideya Fukuzawa Graduate School of Biostudies, Division of Integrated Life Science, Kyoto University Takashi Yamano Graduate School of Biostudies, Division of Integrated Life Science, Kyoto University Microalgae induce a CO2-concentrating mechanism (CCM) to maintain photosynthesis when CO2 is limited. Because this system consumes a substantial portion of photosynthetically generated ATP, its suppression when CO2 levels rise is critical for energy balance, yet the underlying mechanism remains unclear. Here, we identify a nuclear repressor of the CCM in the green alga Chlamydomonas reinhardtii. A pull-down screen for interacting partners of the master activator CCM1/CIA5 revealed an uncharacterized protein that tightly associates with CCM1. This protein, CCM1-binding protein 1 (CBP1), combines a CobW/CobW_C GTP-binding metallochaperone module with a WW-domain characteristic of protein–protein interactions. CBP1 colocalizes and interacts with CCM1 in the nucleus regardless of CO2 conditions. Disruption of CBP1 does not affect growth or CCM induction under CO2 limitation but derepresses 27 of 41 CCM1-dependent low-CO2 inducible genes under high-CO2 conditions. These include the periplasmic and intracellular carbonic anhydrases (CAH1 and LCIB) and inorganic carbon transporters/channels (LCIA, LCI1, BST1, and BST3). Consistently, cbp1 mutants accumulate CAH1 and LCIB proteins and exhibit 40% higher inorganic carbon affinity under high-CO2 conditions; this phenotype is rescued by CBP1 complementation or by acetazolamide treatment. Crucially, cbp1 mutants exhibit significant growth delays under high-CO2 conditions, especially when light is limiting, providing direct evidence that CBP1-mediated repression is essential for energy conservation. Thus, CBP1 prevents unnecessary CCM activity when CO2 is abundant, acting upstream of both transporter/channel and carbonic anhydrase modules. Our findings suggest a regulatory mechanism potentially linking zinc-dependent protein chemistry to CCM gene repression, providing insights into energy-efficient CO2 sensing in aquatic photosynthetic organisms. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1521-6543 65 4 2013 Synthesis of biopterin and related pterin glycosides 300 309 EN Tadashi Hanaya Department of Chemistry, Faculty of Science, Okayama University Hiroshi Yamamoto School of Pharmacy, Shujitsu University Certain pterins having a hydroxyalkyl side chain at C-6 have been found as glycosidic forms in certain prokaryotes, such as 2′-O-(α-D-glucopyranosyl)biopterin from various kinds of cyanobacteria, and limipterin from a green sulfur photosynthetic bacterium. Synthetic studies on glycosides of biopterin and related pterins have been made in view of the structural proof as well as for closer examination of their biological activities and functions. The syntheses of these natural pterin glycosides have effectively been achieved, mostly through appropriately protected N2-(N,N-dimethylaminomethylene)-3-[2-(4-nitrophenyl)ethyl]pterin derivatives as glycosyl acceptors, and are reviewed here. © 2013 IUBMB Life 65(4):300–309, 2013. No potential conflict of interest relevant to this article was reported.

The Japan Institute of Heterocyclic Chemistry Acta Medica Okayama 0385-5414 70 1 2006 Synthesis of 6- and 7-(1,2,3-Trihydroxy-1,2-O-isopropylidenepropyl)pteridines and Deoxygenation of Their 3’-Hydroxy Groups 355 365 EN Tadashi Hanaya Department of Chemistry, Faculty of Science, Okayama University Daisuke Takayama Department of Chemistry, Faculty of Science, Okayama University Hiroshi Yamamoto Department of Chemistry, Faculty of Science, Okayama University Treatment of 3,4-O-isopropylidene-L-threo-pentos-2-ulose (7) with 5,6-diamino-1,3-dimethyluracil (8) afforded 1,3-dimethyl-6-[(1R,2S)-1,2,3-trihydroxy-1,2-O-isopropylidenepropyl]lumazine (9a) and its 7-substituted isomer (9b). Deoxygenation of 3’-hydroxy groups of 9a,b was investigated in connection with a practical transformation of neopterin into biopterin. No potential conflict of interest relevant to this article was reported.

The Japan Institute of Heterocyclic Chemistry Acta Medica Okayama 0385-5414 85 10 2012 Synthetic Studies on Natural Pterin Glycosides 2375 2390 EN Tadashi Hanaya Department of Chemistry, Faculty of Science, Okayama University Hiroshi Yamamoto School of Pharmacy, Shujitsu University Some pterins having various kind of sugars attached to the hydroxyalkyl side-chain at C-6 are known to occur in certain prokaryotes as exemplified by 2'-O-(α-D-glucopyranosyl)biopterin isolated from various kinds of cyanobacteria. A synthetic exploration of various types of glycosides of biopterin and related pterins has been undertaken owing to a marked interest in their physiological functions and biological activities as well as the structural proof of those natural products. This review summarizes our synthetic studies on natural pterin glycosides by employing the appropriately protected N2-(N,N-dimethylaminomethylene)-3-[2-(4-nitrophenyl)ethyl]pterin derivatives as glycosyl accepters. No potential conflict of interest relevant to this article was reported.

The Japan Institute of Heterocyclic Chemistry Acta Medica Okayama 0385-5414 69 1 2006 Synthesis of Functionalized Phospholane Oxides and Phosphorinane Oxides from 1,4- and 1,5-Di-O-Mesyloxy Compounds 283 294 EN Tadashi Hanaya Department of Chemistry, Faculty of Science, Okayama University Karsten Schürrle Department of Chemistry, Faculty of Science, Okayama University Hiroshi Yamamoto Department of Chemistry, Faculty of Science, Okayama University Treatment of 1,4-di-O-mesyl-2,3-di-O-methyl-L-threitol (8b) with phenylphosphine in the presence of sodium hydride in DMSO, followed by the action of hydrogen peroxide, afforded 3,4-dimethoxy-1-phenylphospholane 1- oxide (7), while the same treatment of 1,5-di-O-mesyl-2,3,4-tri-O-methyl-meso- xylitol (11b) provided 2,3,4-trimethoxy-1-phenylphosphorinane 1-oxide (14). No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0022-152X 62 12 2025 An Improved Synthesis of a Key Intermediate for Glycosylation of Biopterin and Its Application for the First Synthesis of Microcystbiopterin B 2021 2029 EN Tadashi Hanaya Department of Chemistry, Faculty of Science, Okayama University Yuta Maeda Department of Chemistry, Faculty of Science, Okayama University Katsuya Iwasaki Department of Chemistry, Faculty of Science, Okayama University A key intermediate for the selective 2′-O-glycosylation of biopterin, N2-(N,N-dimethylaminomethylene)-1′-O-(4-methoxybenzyl)-3-[2-(4-nitrophenyl)ethyl]biopterin (12), was efficiently synthesized via a novel route starting from d-glucose, leading to an improved overall yield. This new pathway involves the preparation of a 5-deoxy-l-arabinose phenylhydrazone derivative (9) as a crucial intermediate in the construction of the pteridine ring. Utilizing compound 12, the first synthesis of microcystbiopterin B (4) was accomplished by glycosylation of 12 with 4,6-di-O-acetyl-2-O-(4-methoxybenzyl)-3-O-methyl-α-d-glucopyranosyl bromide (19) in the presence of silver triflate and tetramethylurea, followed by stepwise deprotection. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0008-6215 558 2025 First total synthesis of cyanopterin, a pterin glycoside isolated from a cyanobacterium 109710 EN Tadashi Hanaya Department of Chemistry, Faculty of Science, Okayama University Yuta Maeda Department of Chemistry, Faculty of Science, Okayama University Kazumasa Ejiri Department of Chemistry, Faculty of Science, Okayama University The first total synthesis and structural identification of cyanopterin, a pterin glycoside isolated from the cyanobacterium Synechocystis sp. PCC 6803, has been accomplished. The synthesis was achieved by convergent coupling of three key derivatives: d-glucuronate, d-galactose, and 6-hydroxymethylpterin. An α-selective glycosylation enabled efficient construction of the glucuronate–galactose disaccharide, while subsequent β-exclusive glycosylation with the 6-hydroxymethylpterin derivative furnished the desired pterin–disaccharide glycoside. Final deprotection provided cyanopterin in its natural form, allowing confirmation of its precise structure. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2050-750X 2026 Multi-step mechanisms of early phospholipid hydrolysis and mineralisation unveiled through combined quantum chemical calculations and experimental analysis EN Keisuke Shibata Department of Materials Science, Waseda University Takahumi Shiotani Department of Resources and Environmental Engineering, Waseda University Yunhao Chen Department of Materials Science, Waseda University Reina Kurihara Department of Resources and Environmental Engineering, Waseda University Katsunori Yamaguchi Department of Resources and Environmental Engineering, Waseda University Emilio Satoshi Hara Department of Advanced International and Information Dentistry, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Nílson Kunioshi Department of Materials Science, Waseda University Phospholipids play key roles in bone formation, with phosphatidylserine (PS) reportedly inducing more rapid mineralisation than phosphatidylcholine (PC); however, the underlying mechanisms remains unclear. This study investigated PS and PC mineralisation using experimental methods and computational chemistry. The stationary points in the potential energy surfaces of the reactions were preliminarily found using a neural network potential (PreFerred Potential in Matlantis) capable of predicting the interaction energies for arbitrary combinations of atoms, and then refined through density functional theory calculations (Gaussian16, at the B3LYP/6-31G(d,p) level of theory). When hydrolysis reactions were assumed to be the initial step in the mineralisation of phospholipids, the results were consistent with empirical analysis. PS was found to be more easily hydrolised than PC, primarily owing to the presence of a labile proton in the NH3+ group of serine that facilitates proton transfer, enhancing hydrolysis of PS at lower energy thresholds. Specifically, when a single phospholipid was considered, three distinct hydrolysis routes were identified: between serine (or choline) and phosphate, between glycerol and phosphate, and between an aliphatic carbon chain and the glycerol backbone. In particular, the initial steps of hydrolysis involved the formation of a pentavalent phosphate intermediate. When calculations were performed with two adjacent phospholipid molecules, the loosely bound proton (H+) in the NH3+ group could be readily transferred either to the P–O bond linking serine to the phosphate group; or to the P–O bond connecting the phosphate to glycerol in a neighboring PS6 molecule. These findings reveal the important roles of serine NH3+ in facilitating hydrolysis of PS, and provide insights for designing novel molecules to accelerate bone regeneration. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1759-9954 16 47 2025 Synthesis of sterically unhindered Lewis acidic boron-doped π-conjugated polymers 5035 5039 EN Naoki Takahashi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University We report the synthesis of sterically unhindered boron-doped π-conjugated polymers via polymerization of organo-dilithium reagents with boron trichloride. The resulting polymer exhibits Lewis acidity and catalyzes the transesterification of methyl benzoate. This performance is attributed to the electron-accepting ability, and thermally labile Lewis acid–base interactions, facilitating catalytic turnover. No potential conflict of interest relevant to this article was reported.

Japan Oil Chemists' Society Acta Medica Okayama 1345-8957 74 11 2025 Bioconversion and Metabolic Fate of the n-1 Polyunsaturated Fatty Acids, 6,9,12,15- Hexadecatetraenoic (C16:4 n-1) and 8,11,14,17- Octadecatetraenoic (C18:4 n-1) Acids, in HepG2 Cells 1023 1032 EN Koki Sugimoto Faculty of Food and Nutritional Sciences, Toyo University Hideto Nishiguchi Faculty of Chemistry, Materials, and Bioengineering, Kansai University Ryota Hosomi Faculty of Chemistry, Materials, and Bioengineering, Kansai University Toshifumi Tanizaki Bizen Chemical Co., Ltd. Tadahiro Tsushima Bizen Chemical Co., Ltd. Naomichi Baba Bizen Chemical Co., Ltd. Yoshihisa Misawa Bizen Chemical Co., Ltd. Ziyi Wang Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Mitsuaki Ono Department of Oral Rehabilitation and Regenerative Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yuki Murakami Department of Hygiene and Public Health, Kansai Medical University Seiji Kanda Department of Hygiene and Public Health, Kansai Medical University Kenji Fukunaga Faculty of Chemistry, Materials, and Bioengineering, Kansai University Fish oil contains not only major fatty acids with double bonds at the n-3, n-6, n-7, and n-9 positions but also those with a double bond at the n-1 position, such as 6,9,12,15-hexadecatetraenoic acid (C16:4 n-1; HDTA). However, intracellular bioconversion and metabolic fate of n-1 polyunsaturated fatty acids (PUFA) remain unclear. Therefore, in this study, we aimed to assess the intracellular bioconversion and metabolic fate of HDTA and its metabolite, 8,11,14,17- octadecatetraenoic acid (C18:4 n-1; ODTA), using HepG2 cells. Based on the results of cell viability and cytotoxicity assays for HDTA and ODTA, the concentration of each fatty acid supplemented in the experiments was set at 10 μM. HepG2 cell culture with HDTA revealed C20:4 n-1 as a new HDTA metabolite, along with previously reported ODTA. Our findings suggest that the HDTA taken up by HepG2 cells undergoes elongation to form ODTA and C20:4 n-1. Following supplementation with HDTA, ODTA, and 5,8,11,14,17-eicosapentaenoic acid (C20:5 n-3; EPA), fatty acids disappeared from the culture medium within 24 h. Notably, the total relative level of HDTA and its metabolites, including ODTA and C20:4 n-1 in HDTA- and ODTA-supplemented cells were significantly lower than the total relative level of EPA and its metabolites, including 7,10,13,16,19-docosapentaenoic acid (C22:5 n-3), C24:6 n-3, and 4,7,10,13,16,19-docosahexaenoic acid (C22:6 n-3) in the EPA-supplemented cells. Except for a portion that was intracellularly elongated, most HDTA was taken up by HepG2 cells and may undergo rapid fatty acid β-oxidation. However, RNA-sequencing and real-time polymerase chain reaction analysis revealed no significant changes in fatty acid β-oxidation–related gene expression levels in HDTA-supplemented cells. Collectively, these results provide novel insights into the intracellular bioconversion mechanisms and metabolic fate of HDTA and ODTA in HepG2 cells, suggesting that the metabolic fate of n-1 PUFA is distinct from that of common PUFA. No potential conflict of interest relevant to this article was reported.

International Union of Crystallography (IUCr) Acta Medica Okayama 2056-9890 82 2 2026 Crystal structure of tris[4-(3,4-dimethoxythiophen-2-yl)phenyl]amine E82 EN Masafumi Yano Kansai University Yukiyasu Kashiwagi Osaka Research Institute of Industrial Science and Technology Koki Oishi Kansai University Minori Yano Kansai University Koichi Mitsudo Okayama University In the title compound tris[4-(3,4-dimethoxythiophen-2-yl)phenyl]amine (DMOT-TPA), C36H33NO6S3, the central nitrogen atom shows no pyramidalization, with the three para-phenylene rings arranged in a propeller-like geometry. Each thiophene ring is twisted by about 25–29° relative to the adjacent phenylene ring, giving a distorted π-conjugated framework. In the crystal, molecules are linked through multiple C―H⋯π interactions into two-dimensional sheets, which extend into a three-dimensional network. A Cambridge Structural Database survey revealed no prior examples of triphenylamines bearing 3,4-dimethoxythiophen units at the para positions. This unique structure provides new insights into the design of redox-active organic materials. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2694-2445 5 6 2025 Electronic Structure of the S1 State Manganese Cluster in Photosystem II Investigated Using Q-Band Selective Hole-Burning 660 671 EN Shinya Kosaki Department of Physics, Graduate School of Science, Nagoya University Naohiko Nakamura Department of Physics, Graduate School of Science, Nagoya University Yoshiki Nakajima Research Institute for Interdisciplinary Science, Advanced Research Field, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Jian-Ren Shen Research Institute for Interdisciplinary Science, Advanced Research Field, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hiroyuki Mino Department of Physics, Graduate School of Science, Nagoya University The electronic structure of the S1 state of photosystem II (PSII) was investigated using selective hole burning of Q-band pulsed electron paramagnetic resonance. The free induction decay and spin–echo signals of the tyrosine radical YD• in the plant PSII oscillated because of the magnetic dipole–dipole interaction with the S1 state Mn cluster. The initial period was 410 ns (2.44 MHz) and was assigned to the S = 1 spin state. Based on the oscillation analysis, both Mn1 and Mn4 and both Mn2 and Mn3 were assigned as Mn(III) and Mn(IV), respectively, which is consistent with the quantum chemical calculations. The 410 ns period was accounted for in the simplified model using the isotropic spin density distribution ratio [1.6:–1.1:–1.1:1.6] for Mn1–4 ions. This oscillation was identical with that observed in the presence of methanol. The oscillation decreased in PsbP/Q- and PsbO/P/Q-depleted PSII. In Thermosynechococcus vulcanus, two periods, 390 ns (2.56 MHz) and 630 ns (1.59 MHz), were detected, indicating that the cyanobacterial S1 state includes two isomers, S = 1 and S ≥ 2 spins. The S ≥ 2 spin was not detected in PsbO/U/V-depleted PSII without polyethylene glycol. The S ≥ 2 state was consistent with the reported quantum chemical calculation using S = 3. A simplified model accounted for the S = 1 state as the spin density distribution [1.8:–1.3:–1.3:1.8] and for the S ≥ 2 state as the isotropic spin density distribution [－0.5:0.5:0.5:0.5] for Mn1–4 ions. In combination with quantum chemical calculations, the most probable protonated structure is W1 = H2O, W2 = H2O, O4 = O2–, and O5 = O2– for the S1 state. These results demonstrate that the selective hole burning method is a powerful tool to complement X-ray studies to determine the valence and protonation structure of manganese clusters, not only in the S1 state but also in higher S-states and general metal clusters, which would provide important insights into the water oxidation mechanism. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0753-3322 193 2025 Deciphering the structural impact of norepinephrine analog radiopharmaceuticals on organic cation transporter affinity 118724 EN Saskia Mühlig Department of Nuclear Medicine and Comprehensive Heart Failure Center, University Hospital Würzburg Xinyu Chen Nuclear Medicine, Faculty of Medicine, University of Augsburg Anna Tutov Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy and Food Chemistry, University of Würzburg Naoko Nose Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Constantin Lapa Nuclear Medicine, Faculty of Medicine, University of Augsburg Rudolf A. Werner Department of Nuclear Medicine, LMU Hospital, Ludwig-Maximilians-University of Munich Michael Decker Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy and Food Chemistry, University of Würzburg Takahiro Higuchi Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Purpose: Previous studies have investigated the kinetics and affinities of norepinephrine transporter (NET)-targeting radiotracers, including [123I]MIBG, but the role of organic cation transporters (OCTs) remains unclear. This study aimed to evaluate how the structural design of selective NET-targeting tracers affects OCT-mediated non-specific uptake, identifying factors influencing both NET and OCT affinity. Methods: Cellular uptake assays were conducted using SK-N-SH cells expressing human NET, and human OCT1-, OCT2-, and OCT3-expressing cells with [3H]norepinephrine, [3H]MPP+, and [131I]MIBG. Competitive uptake assays used non-radioactive reference compounds for several NET-targeting radiopharmaceuticals (MIBG, HED, EPI, PHEN, LMI1195, and PHPG), along with a new PET radiotracer [18F]AF78, and its two analogs with meta-iodide [18F]AF78(I) or hydroxyl group [18F]AF78(OH). Dynamic PET imaging in non-human primates assessed the in vivo uptake of [18F]AF78 after NET inhibition with desipramine. Results: Monoamine-based tracers (EPI, PHEN, HED) exhibited high NET selectivity with minimal OCTs interaction, while guanidine-containing tracers (e.g., MIBG, LMI1195) displayed substantial OCTs affinity. Lower lipophilicity in guanidine-containing compounds, influenced by substitutions on the benzene ring (e.g., PHPG, AF78), correlated with weaker OCT interactions. PET imaging confirmed that cardiac uptake of [18F]AF78 is sensitive to desipramine pretreatment (***P < 0.0005), indicating its NET-specificity, while persistent hepatic retention suggests an OCT-mediated transport mechanism. Conclusion: This study highlights the critical influence of the compounds’ chemical structure on NET and OCT affinities. Structural modifications that reduce OCT-mediated uptake while maintaining high NET affinity could improve the specificity and theranostic potential of NET-targeting ligands. These findings provide insights for designing next-generation radiotracers with enhanced selectivity and clinical utility. No potential conflict of interest relevant to this article was reported.

Frontiers Media SA Acta Medica Okayama 1664-042X 16 2025 Activation of the pentose phosphate pathway by microcurrent stimulation mediates antioxidant effects in inflammation-stimulated macrophages 1666999 EN Mikiko Uemura Department of Rehabilitation Science, Kobe University Graduate School of Health Sciences Noriaki Maeshige Department of Rehabilitation Science, Kobe University Graduate School of Health Sciences Atomu Yamaguchi Department of Rehabilitation Science, Kobe University Graduate School of Health Sciences Xiaoqi Ma Department of Rehabilitation Science, Kobe University Graduate School of Health Sciences Yunfei Fu Department of Rehabilitation Science, Kobe University Graduate School of Health Sciences Taketo Inoue Assisted Reproductive Technology Center, Okayama University Mami Matsuda Graduate School of Science, Technology and Innovation, Kobe University Yuya Nishimura Graduate School of Science, Technology and Innovation, Kobe University Tomohisa Hasunuma Graduate School of Science, Technology and Innovation, Kobe University Ji Wang Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University Hiroyo Kondo Department of Nutrition, Faculty of Health and Nutrition, Shubun University Hidemi Fujino Department of Rehabilitation Science, Kobe University Graduate School of Health Sciences Introduction: Excessive inflammatory responses in macrophages lead to increased oxidative stress, and the excessive production of reactive oxygen species (ROS) causes tissue damage, contributing to the development of chronic diseases and tissue deterioration. Therefore, controlling the inflammatory response and ROS production is crucial for human health. Electrical stimulation (ES) has been shown to have antioxidant and anti-inflammatory effects on macrophages. However, the key pathway underlying these effects remains unclear. Methods: In this study, ES was applied to Lipopolysaccharide (LPS)-stimulated macrophages, and the production of ROS and 8–hydroxy–2′–deoxyguanosine (8-OHdG), inflammatory cytokine expression, and intracellular metabolites were analyzed in a glucose-6-phosphate dehydrogenase (G6PD) knockdown experiment, the rate-limiting enzyme of the Pentose Phosphate Pathway(PPP). Results: ES significantly increased sedoheptulose 7-phosphate (S7P), an intermediate metabolite in PPP, and reduced ROS and 8-OHdG production and the expression of inflammatory cytokines in LPS-stimulated macrophages. Meanwhile, ES did not exert antioxidant effects in G6PD-knockdown macrophages. Discussion: These findings indicate that the antioxidant effects of ES are mediated by PPP in LPS-stimulated macrophages. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0969-806X 237 2025 Impact of different X-ray tube positions on actual dose measurements during CT examinations -An effect of patient physique- 113001 EN Hiroaki Hayashi College of Transdisciplinary Sciences for Innovation, Kanazawa University Tatsuya Maeda Graduate School of Medical Sciences, Kanazawa University Kazuki Takegami Department of Radiological Technology, Yamaguchi University Hospital Sota Goto Faculty of Health Sciences, Kobe Tokiwa University Takashi Asahara Department of Radiological Technology, Faculty of Health Sciences, Okayama University Natsumi Kimoto Department of Radiological Science, Faculty of Health Sciences, Junshin Gakuen University Rina Nishigami Graduate School of Medical Sciences, Kanazawa University Daiki Kobayashi Graduate School of Medical Sciences, Kanazawa University Yuki Kanazawa Faculty of Life Science, Kumamoto University Kazuta Yamashita Department of Orthopedics, School of Medicine, Tokushima University Takeshi Konishi MEDITEC JAPAN Co., Ltd. Motochika Maki MEDITEC JAPAN Co., Ltd. Dose management of patients is very important during X-ray Computed Tomography (CT) examinations, but because the patient's surface dose is inhomogeneous, it is difficult to measure the most probable value using a small passive-type dosimeter, lent to the patient. To solve this problem, our research group developed a precise dose analysis procedure in which a systematic uncertainty related to the X-ray incident direction (θin) is reduced. θin information was analyzed from CT images. However, the applicability of our procedure to actual patients with various physiques has not been examined. This study aims to propose a dose analysis procedure that can be applied to patients with various physiques, and to show its impact on dose measurement. Clinical data of 198 patients with Body Mass Index (BMI) values between 15 and 40 kg/m2 (mean value: 23.1 ± 3.8 kg/m2) who underwent chest CT scans were analyzed after dividing them into three groups based on BMI values. The absorbed dose was measured with a small-type Optically Stimulated Luminescence (OSL) dosimeter. To derive correction factors related to θin, the dependence of the actually-measured dose values of various patients on θin was analyzed. The correction coefficients were determined independently for the three groups classified by BMI values. By correcting the effect of θin, the systematic uncertainty element could be reduced, resulting in 30 % reduction of the uncertainty. Furthermore, it was found that our analysis procedure makes it possible to visualize outliers. In comparison with the expected dose values based on Computed Tomography Dose Index (CTDI) values, most of the data fell within the range of ±1.34 mGy (=1σ). However, 7 % of the data showed large deviations larger than 2σ. In conclusion, our research group has developed a procedure for measuring patient surface doses that can be applied to patients having various physiques, in which the effects of X-ray incident direction were accurately corrected. The procedure could be one solution to the problems with actual dose measurements during CT examinations, and will be useful for dose management based on the small-type dosimeter. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2155-5435 15 14 2025 Mesoporous Oxyhalide Aggregates Exhibiting Improved Photocatalytic Activity for Visible-Light H2 Evolution and CO2 Reduction 12551 12562 EN Hiroto Ueki Department of Chemistry, School of Science, Institute of Science Tokyo Toshiya Tanaka Department of Chemistry, School of Science, Institute of Science Tokyo Shuji Anabuki Graduate School of Natural Science and Technology, Okayama University Ryuichi Nakada Department of Chemistry, School of Science, Institute of Science Tokyo Megumi Okazaki Department of Chemistry, School of Science, Institute of Science Tokyo Kenta Aihara Department of Chemistry, School of Science, Institute of Science Tokyo Masashi Hattori Materials and Structures Laboratory, Institute of Integrated Research, Institute of Science Tokyo Fumitaka Ishiwari Department of Applied Chemistry, Graduate School of Engineering, Osaka University Rie Haruki Institute of Materials Structure Science, High Energy Accelerator Research Organization Shunsuke Nozawa Institute of Materials Structure Science, High Energy Accelerator Research Organization Toshiyuki Yokoi Nanospace Catalysis Unit, Institute of Integrated Research, Institute of Science Tokyo Michikazu Hara Materials and Structures Laboratory, Institute of Integrated Research, Institute of Science Tokyo Osamu Ishitani Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University Akinori Saeki Department of Applied Chemistry, Graduate School of Engineering, Osaka University Akira Yamakata Graduate School of Natural Science and Technology, Okayama University Kazuhiko Maeda Department of Chemistry, School of Science, Institute of Science Tokyo Oxyhalides are promising visible-light photocatalysts for water splitting and CO2 conversion; however, those exhibiting high activity for these reactions have rarely been reported. Here, we show that using water-soluble Ti complexes as precursors in the microwave-assisted hydrothermal synthesis of the oxyhalide photocatalyst Pb2Ti2O5.4F1.2 (PTOF) resulted in the production of nanoparticulate PTOF. The primary particle size of the synthesized PTOF ranged from several tens of nanometers to several hundreds of nanometers. Using Ti-citric acid or Ti-tartaric acid complexes as precursors, the PTOF was formed as mesoporous aggregates, compared with a bulky analogue (0.5–1 μm) prepared using a TiCl4 precursor. The PTOF prepared from Ti-citric acid complex had a particle size of 50–100 nm and showed a one-order-of-magnitude greater activity for H2 evolution from an aqueous ethylenediaminetetraacetic acid solution with the aid of a Rh cocatalyst. An apparent quantum yield (AQY) of 15.4 ± 1.0% at 420 nm, which is the highest among the reported oxyhalide photocatalysts, was achieved under optimal conditions. Although excess particle size reduction of PTOF lowered the H2 evolution activity, the PTOF with the smallest possible primary particle size of 15–30 nm, prepared from Ti-tartaric acid complex, showed the highest activity toward the selective reduction of CO2 into formate in a nonaqueous environment when combined with a binuclear Ru(II) complex. The CO2 reduction AQY was 10.4 ± 1.8% at 420 nm, a record-high value among metal-complex/semiconductor binary hybrid photocatalysts. This study highlights the importance of morphological control of oxyhalides for realizing their full potential as photocatalysts for artificial photosynthesis. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2574-0962 8 6 2025 Effects of Metal-Cation Doping on Photocatalytic H2 Evolution Activity of Layered Perovskite Oxynitride K2LaTa2O6N 3541 3552 EN Hideya Tsuchikado Department of Chemistry, School of Science, Institute of Science Tokyo Shuji Anabuki Graduate School of Natural Science and Technology, Okayama University Ovidiu Cretu Electron Microscopy Group, National Institute for Materials Science (NIMS) Yuki Kinoshita Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Institute of Science Tokyo Masashi Hattori Institute of Integrated Research, Institute of Science Tokyo Yuta Shiroma Department of Chemistry, School of Science, Institute of Science Tokyo Dongxiao Fan Institute of Materials Structure Science High Energy Accelerator Research Organization Megumi Okazaki Department of Chemistry, School of Science, Institute of Science Tokyo Takuto Soma Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Institute of Science Tokyo Fumitaka Ishiwari Department of Applied Chemistry, Graduate School of Engineering, Osaka University Shunsuke Nozawa Institute of Materials Structure Science High Energy Accelerator Research Organization Toshiyuki Yokoi Institute of Integrated Research, Institute of Science Tokyo Michikazu Hara Institute of Integrated Research, Institute of Science Tokyo Koji Kimoto Electron Microscopy Group, National Institute for Materials Science (NIMS) Akira Yamakata Graduate School of Natural Science and Technology, Okayama University Akinori Saeki Department of Applied Chemistry, Graduate School of Engineering, Osaka University Kazuhiko Maeda Department of Chemistry, School of Science, Institute of Science Tokyo Aliovalent cation doping into a heterogeneous photocatalyst affects several of its physicochemical properties, including its morphological characteristics, optical absorption behavior, and charge carrier dynamics, causing a drastic change in its photocatalytic activity. In the present work, we investigated the effects of aliovalent cation doping on the visible-light H2-evolution photocatalytic activity of the Ruddlesden–Popper layered perovskite oxynitride K2LaTa2O6N. The photocatalytic activity toward H2 evolution from an aqueous NaI solution was found to be enhanced by an increase in the specific surface area of the K2LaTa2O6N photocatalyst, which could be realized upon doping with lower-valence cations (e.g., Mg2+, Al3+, and Ga3+). Among the dopants examined at 1 mol % doping, Ga resulted in the highest activity. The activity of the Ga-doped specimen was further improved with increasing Ga concentration, where the maximal activity was obtained at 10 mol %, corresponding to an apparent quantum yield of 2.7 ± 0.4% at 420 nm from aqueous methanol. This number is the highest reported for a layered oxynitride photocatalyst. In the Ga-doped K2LaTa2O6N, a trade-off was observed between the Ga concentration and the photocatalytic activity. Although doping with Ga reduced the particle size of K2LaTa2O6N and suppressed undesirable charge recombination, it led to an enlarged bandgap, unsuitable for visible-light absorption. No potential conflict of interest relevant to this article was reported.

Biophysical Society of Japan Acta Medica Okayama 2189-4779 22 3 2025 Origin of the unique topology of the triangular water cluster in Rubrobacter xylanophilus rhodopsin e220018 EN Tomoyasu Noji Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo Masaki Tsujimura Department of Advanced Interdisciplinary Studies, The University of Tokyo Keisuke Saito Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo Keiichi Kojima Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuki Sudo Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hiroshi Ishikita Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo The crystal structure of Rubrobacter xylanophilus rhodopsin (RxR) reveals a triangular cluster of three water molecules (W413, W415, and W419) at the extracellular proton-release site, near Glu187 and Glu197. Using a quantum mechanical/molecular mechanical approach, we identified the structural nature of this unique water cluster. The triangular shape is best reproduced when all three water molecules are neutral H2O with protonated Glu187 and deprotonated Glu197. Attempts to place H3O+ at any of these water molecules result in spontaneous proton transfer to one of the acidic residues and significant distortion from the crystal structure. The plane defined by the triangular water cluster extends into the guanidinium plane of Arg71, with both aligned along the W413...W419 axis. This extended plane lies nearly perpendicular to a five-membered, ring-like H-bond network involving two carboxyl oxygen atoms from Glu187 and one from Glu197. The resulting bipartite planar architecture, defined by the water triangle, Arg71, and the Glu187/Glu197 network may reflect the exceptional thermal stability in RxR. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1433-7851 64 13 2025 Conduction Band and Defect Engineering for the Prominent Visible‐Light Responsive Photocatalysts e202419624 EN Akira Yamakata Graduate School of Natural Science and Technology, Okayama University Kosaku Kato Graduate School of Natural Science and Technology, Okayama University Takafumi Ogawa Nanostructures Research Laboratory, Japan Fine Ceramics Center Kanta Ogawa Department of Energy and Hydrocarbon Chemistry Graduate School of Engineering, Kyoto University Makoto Ogawa Department of Energy and Hydrocarbon Chemistry Graduate School of Engineering, Kyoto University Daichi Kato Department of Energy and Hydrocarbon Chemistry Graduate School of Engineering, Kyoto University Chengchao Zhong Department of Energy and Hydrocarbon Chemistry Graduate School of Engineering, Kyoto University Akihide Kuwabara Nanostructures Research Laboratory, Japan Fine Ceramics Center Ryu Abe Department of Energy and Hydrocarbon Chemistry Graduate School of Engineering, Kyoto University Hiroshi Kageyama Department of Energy and Hydrocarbon Chemistry Graduate School of Engineering, Kyoto University Controlling trap depth is crucial to improve photocatalytic activity, but designing such crystal structures has been challenging. In this study, we discovered that in 2D materials like BiOCl and Bi4NbO8Cl, composed of interleaved [Bi2O2]2+ and Cl- slabs, the trap depth can be controlled by manipulating the slab stacking structure. In BiOCl, oxygen vacancies (VO) create deep electron traps, while chlorine vacancies (VCl) produce shallow traps. The depth is determined by the coordination around anion vacancies: VO forms strong σ bonds with Bi-6p dangling bonds below the conduction band minimum (CBM), while those around Cl are parallel, forming weak π-bonding. The strong re-hybridization makes the trap depth deeper. In Bi4NbO8Cl, VCl also creates shallow traps, but VO does not produce deep traps although Bi-6p orbitals are also forming strong σ bonding. This difference is attributed to the difference of the energy level of CBM. In both cases, the CBM consists of Bi-6p orbitals extending into the Cl layers. However, these orbitals are isolated in BiOCl, but those in Bi4NbO8Cl are bonded with each other between neighboring [Bi2O2]2+ layers. This unique bonding-based CBM prevents the formation of deep electron traps, and significantly enhances H2 evolution activity by prolonging the lifetime of highly reactive free electrons. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1463-9262 27 18 2025 Deoxygenative dual CO2 conversions: methylenation and switchable N-formylation/N-methylation of tryptamines 5359 5365 EN Kazuto Takaishi Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hajime Morishita Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kosuke Iwaki Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tadashi Ema Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University The unprecedented one-pot synthesis of N-formyl/N-methyltryptolines from tryptamines was achieved via phenylsilane-assisted deoxygenative dual CO2 conversions. Two CO2 molecules acted as different synthons and were converted into methylene and N-formyl/N-methyl groups. The CO2 reduction step was catalyzed by a pentanuclear zinc complex at atmospheric pressure under solvent-free conditions. The N-formyl/N-methyl products could be switched by changing the amount of phenylsilane, and the amounts of in situ generated bis(silyl)acetals and silyl formates were key to the chemoselectivity. Methylenation, N-formylation, and N-methylation proceeded via the Pictet–Spengler reaction, amine–acid condensation, and the Eschweiler–Clarke reaction, respectively. The CO2 reduction with phenylsilane could also be applied to the one-pot three-step synthesis of spiro[oxindole-pyrrolidine]s. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2574-0962 2025 Enhanced Charge-Transfer Kinetics Enabled by ZrO2–Based Dielectric Layers in Lithium-Ion Batteries EN Takashi Teranishi Graduate School of Natural Science and Technology, Okayama University Yusuke Higaki Graduate School of Natural Science and Technology, Okayama University Tomonori Imamura Graduate School of Natural Science and Technology, Okayama University Motoki Horibe Department of Advanced Ceramics, Nagoya Institute of Technology Shinya Kondo Department of Energy Engineering, Nagoya University Chinatsu Sasaoka R&D Laboratory, Nippon Denko Co., Ltd. Hikaru Hirabaru R&D Laboratory, Nippon Denko Co., Ltd. Shingo Katayama R&D Laboratory, Nippon Denko Co., Ltd. Masanobu Nakayama Department of Advanced Ceramics, Nagoya Institute of Technology Akira Kishimoto Graduate School of Natural Science and Technology, Okayama University The development of high-rate capability lithium-ion batteries (LIBs) requires suppression of charge-transfer resistance (RCT) at electrode–electrolyte interfaces. Here, zirconia-based dielectric oxides (MZ; M = Y, Gd, Sm, Er, etc.) were introduced onto LiCoO2 (LCO) surfaces as electronically and ionically insulating modifiers to accelerate interfacial ion transport. Electrochemical impedance spectroscopy showed that Y2O3 modified ZrO2 (YZ) decoration reduced RCT from 75.8 Ω in reference LCO to 38.3 Ω, accompanied by a 2.3-fold improvement in capacity retention at 20C. Density functional theory molecular dynamics (DFT–MD) simulations showed that solvated Li ions coordinate with surface oxygen atoms in discharging, and that adsorption energies are governed by local charge distributions determined by stabilizing cations. Optimal adsorption activity, and thus the lowest RCT, occurred when the surface charge corrugation was balanced. These findings provide design principles for dielectric interface engineering to enhance rate capability of LIBs. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2771-9316 2025 Photochemical Macrolactonization of Hydroxyaldehydes via C–H Bromination EN Sakura Kodaki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haru Ando 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 Research Institute for Interdisciplinary Science, Okayama University 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 Efficient and stable n-type sulfide overall water splitting with separated hydrogen production 8786 EN Haolin Luo Research Center for Combustion and Environment Technology, Shanghai Jiao Tong University Zhixi Liu Research Center for Combustion and Environment Technology, Shanghai Jiao Tong University Haifeng Lv State Key Laboratory of Precision and Intelligent Chemistry, School of Chemistry and Material Sciences, and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), University of Science and Technology of China Junie Jhon M. Vequizo Institute of Aqua Regeneration, Shinshu University Mengting Zheng College of Chemical and Biological Engineering, Zhejiang University Feng Han Research Center for Combustion and Environment Technology, Shanghai Jiao Tong University Zhen Ye Research Center for Combustion and Environment Technology, Shanghai Jiao Tong University Akira Yamakata Faculty of Natural Science and Technology, Okayama University Wenfeng Shangguan Research Center for Combustion and Environment Technology, Shanghai Jiao Tong University Adam F. Lee Centre for Catalysis and Clean Energy, School of Environment and Science, Griffith University Xiaojun Wu State Key Laboratory of Precision and Intelligent Chemistry, School of Chemistry and Material Sciences, and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), University of Science and Technology of China Domen Kazunari Institute of Aqua Regeneration, Shinshu University Jun Lu College of Chemical and Biological Engineering, Zhejiang University Zhi Jiang Research Center for Combustion and Environment Technology, Shanghai Jiao Tong University N-type sulfide semiconductors are promising photocatalysts due to their broad visible-light absorption, facile synthesis and chemical diversity. However, photocorrosion and limited electron transport in one-step excitation and solid-state Z-scheme systems hinder efficient overall water splitting. Liquid-phase Z-schemes offer a viable alternative, but sluggish mediator kinetics and interfacial side reactions impede their construction. Here we report a stable Z-scheme system integrating n-type CdS and BiVO₄ with a [Fe(CN)₆]³⁻/[Fe(CN)₆]⁴⁻ mediator, achieving 10.2% apparent quantum yield at 450 nm with stoichiometric H₂/O₂ evolution. High activity reflects synergies between Pt@CrOx and Co3O4 cocatalysts on CdS, and cobalt-directed facet asymmetry in BiVO₄, resulting in matched kinetics for hydrogen and oxygen evolution in a reversible mediator solution. Stability is dramatically improved through coating CdS and BiVO4 with different oxides to inhibit Fe4[Fe(CN)6]3 precipitation and deactivation by a hitherto unrecognized mechanism. Separate hydrogen and oxygen production is also demonstrated in a two-compartment reactor under visible light and ambient conditions. This work unlocks the long-sought potential of n-type sulfides for efficient, durable and safe solar-driven hydrogen production. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1479-5876 23 1 2025 Tumor marker–guided precision BNCT for CA19-9–positive cancers: a new paradigm in molecularly targeted chemoradiation therapy 1387 EN Noriyuki Kanehira Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Fuminori Teraishi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tomoyuki Tajima Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tatsunori Osone Department of Regenerative Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuyoshi Gotoh Department of Medical Laboratory Science, Okayama University Graduate School of Health Sciences Takuya Fujimoto Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yoshinori Sakurai Institute for Integrated Radiation and Nuclear Science, Kyoto University Natsuko Kondo Institute for Integrated Radiation and Nuclear Science, Kyoto University Narikazu Nagahisa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kaoru Kamei Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Taiga Fujita Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Akira Morihara Graduate School of Environmental, Life Science, Okayama University Yutaka Takaguchi Faculty of Sustainable Design, Department of Material Design and Engineering, University of Toyama Mizuki Kitamatsu Department of Applied Chemistry, Kindai University Takeshi Takarada Department of Regenerative Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kunitoshi Shigeyasu Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Minoru Suzuki Institute for Integrated Radiation and Nuclear Science, Kyoto University Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroyuki Michiue Neutron Therapy Research Center, Okayama University Background: Boron neutron capture therapy (BNCT) is a molecularly targeted chemoradiation modality that relies on boron delivery agents such as p-borophenylalanine (BPA), which require LAT1 (L-type amino acid transporter 1) for tumor uptake. However, the limited efficacy of BPA in LAT1-low tumors restricts its therapeutic scope. To address this limitation, we developed a tumor marker–guided BNCT strategy targeting cancers overexpressing the clinically validated glycan biomarker CA19-9. Methods: We conducted transcriptomic analyses using The Cancer Genome Atlas (TCGA) datasets to identify LAT1-low cancers with high CA19-9 expression. These analyses revealed elevated expression of fucosyltransferase 3 (FUT3), which underlies CA19-9 biosynthesis, in pancreatic, biliary, and ovarian malignancies. Based on this, we synthesized a novel boron compound, fucose-BSH, designed to selectively accumulate in CA19-9–positive tumors. We evaluated its physicochemical properties, pharmacokinetics, biodistribution, and antitumor efficacy in cell lines and xenograft models, comparing its performance to that of BPA. Results: Fucose-BSH demonstrated significantly greater boron uptake in CA19-9–positive cell lines (AsPC-1, Panc 04.03, HuCCT-1, HSKTC, OVISE) compared to CA19-9–negative PANC-1. In HuCCT-1 xenografts, boron accumulation reached 36.2 ppm with a tumor/normal tissue ratio of 2.1, outperforming BPA. Upon neutron irradiation, fucose-BSH–mediated BNCT achieved > 80% tumor growth inhibition. Notably, fucose-BSH retained therapeutic efficacy in LAT1-deficient models where BPA was ineffective, confirming LAT1-independent targeting. Conclusions: This study establishes a novel precision BNCT approach by leveraging CA19-9 as a tumor-selective glycan marker for boron delivery. Fucose-BSH offers a promising platform for expanding BNCT to previously inaccessible LAT1-low malignancies, including pancreatic, biliary, and ovarian cancers. These findings provide a clinically actionable strategy for tumor marker–driven chemoradiation and lay the foundation for translational application in BNCT. This strategy has the potential to support companion diagnostic development and precision stratification in ongoing and future BNCT clinical trials. Translational Relevance: Malignancies with elevated CA19-9 expression, such as pancreatic, biliary, and ovarian cancers, are associated with poor prognosis and limited response to current therapies. This study presents a tumor marker–guided strategy for boron neutron capture therapy (BNCT) by leveraging CA19-9 glycan biology to enable selective tumor targeting via fucose-BSH, a novel boron compound. Through transcriptomic data mining and preclinical validation, fucose-BSH demonstrated LAT1-independent boron delivery, potent BNCT-mediated cytotoxicity, and tumor-specific accumulation in CA19-9–positive models. These findings support a precision chemoradiation approach that addresses a critical gap in BNCT applicability, offering a clinically actionable pathway for patient stratification and therapeutic development in CA19-9–expressing cancers. No potential conflict of interest relevant to this article was reported.

AIP Publishing Acta Medica Okayama 0021-9606 163 19 2025 Interplay of coil–globule transitions and aggregation in homopolymer aqueous solutions: Simulation and topological insights 191101 EN Junichi Komatsu Department of Chemistry, Faculty of Science, Okayama University Kenichiro Koga Department of Chemistry, Faculty of Science, Okayama University Jonas Berx Niels Bohr International Academy, Niels Bohr Institute, University of Copenhagen We investigate the structural and topological properties of hydrophobic homopolymer chains in aqueous solutions using molecular dynamics simulations and circuit topology (CT) analysis. By combining geometric observables, such as the radius of gyration and the degree of aggregation, with CT data, we capture the relationship between coil–globule and aggregation transitions, resolving the system’s structural changes with temperature. Our results reveal a temperature-driven collective transition from isolated coiled chains to globular aggregates. At a characteristic transition temperature Tc, each chain in multichain systems undergoes a rapid coil–globule collapse, coinciding with aggregation, in contrast to the gradual collapse observed in single-chain systems at infinite dilution. This collective transition is reflected in geometric descriptors and a reorganization of CT motifs, shifting from intrachain-dominated motifs at low temperatures to a diverse ensemble of multichain motifs at higher temperatures. CT motif enumeration provides contact statistics while offering a topologically detailed view of polymer organization. These findings highlight CT’s utility as a structural descriptor for polymer systems and suggest applications for biopolymer aggregation and folding. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2073-4344 15 2 2025 Palladium-Catalyzed Decarbonylative Nucleophilic Halogenation of Acid Anhydrides 191 EN Tian Tian Graduate School of Natural Science and Technology, Okayama University Shuhei Uei Department of Chemistry, Faculty of Science, Okayama University Weidan Yan Graduate School of Natural Science and Technology, Okayama University Yasushi Nishihara Research Institute for Interdisciplinary Science (RIIS), Okayama University In this study, we developed a palladium-catalyzed decarbonylative nucleophilic halogenation reaction using inexpensive and readily available acid anhydrides as substrates. This approach effectively circumvents the instability of acyl chlorides and the low reactivity of acyl fluorides. The Pd/Xantphos catalyst system exhibited excellent compatibility with the thermodynamically and kinetically challenging reductive elimination of C–X bonds (X = I, Br, and Cl) from Pd(II) intermediates. Notably, for electron-donating substrates, adopting an open system significantly improved the reaction efficiency. The positive effect of the open system may be due to the reversible nature of CO insertion and deinsertion, which helps direct the reaction toward the desired pathway by allowing the generated CO to exit the reaction system. Mechanistic studies suggest that the reaction proceeds through a highly reactive acyl halide intermediate, followed by a unimolecular fragment coupling (UFC) pathway via decarbonylation or an alternative pathway involving the formation of an activated anionic palladate complex in the presence of lithium halide. No potential conflict of interest relevant to this article was reported.

American Society for Microbiology Acta Medica Okayama 2379-5042 2025 Analysis of the drug target of the anti-tuberculosis compound OCT313: phosphotransacetylase is a potential drug target for anti-mycobacterial agents e00463-25 EN Takemasa Takii Department of Mycobacterium Reference and Research, the Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association Tomohiro Hasegawa Department of Hygienic Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University Saotomo Itoh Department of Hygienic Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University Shinji Maeda Graduate School of Pharmaceutical Sciences, Hokkaido University of Sciences Takayuki Wada Department of Microbiology, Graduate School of Human Life and Ecology, Osaka Metropolitan University Yasuhiro Horita Department of Clinical Pharmaceutics, Graduate School of Medical Sciences, Nagoya City University Akihito Nishiyama Department of Bacteriology, Niigata University School of Medicine Sohkichi Matsumoto Department of Bacteriology, Niigata University School of Medicine Naoya Ohara Department of Oral Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Aoi Kimishima Laboratory of Applied Microbial Chemistry, Ōmura Satoshi Memorial Institute, Kitasato University Yukihiro Asami Laboratory of Applied Microbial Chemistry, Ōmura Satoshi Memorial Institute, Kitasato University Shigeaki Hida Department of Hygienic Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University Kikuo Onozaki Department of Hygienic Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University Tuberculosis (TB) is one of the most common infectious diseases caused by bacteria worldwide. The increasing prevalence of multidrug-resistant TB (MDR-TB) and latent TB infection (LTBI) has intensified the global TB burden. Therefore, the development of new drugs for MDR-TB and LTBI is urgently required. We have reported that the derivative of dithiocarbamate sugar derivative, 2-acetamido-2-deoxy-β-D-glucopyranosyl N,N-dimethyldithiocarbamate (OCT313), exhibits anti-mycobacterial activity against MDR-MTB. Here, we identified the target of OCT313. In experimentally generated OCT313-resistant bacteria, adenine at position 1,092 in the metabolic enzyme phosphotransacetylase (PTA) gene was replaced with cytosine. This mutation is a nonsynonymous mutation that converts methionine to leucine at position 365 in the PTA protein. OCT313 inhibited the enzymatic activity of recombinant wild-type PTA, but not of the mutant PTA (M365L). PTA is an enzyme that produces acetyl-coenzyme A (acetyl-CoA) from acetyl phosphate and CoA and is involved in metabolic pathways; therefore, it was expected to also be active against dormant Mycobacterium tuberculosis bacilli. OCT313 exhibits antibacterial activity in the Wayne model of dormancy using Mycobacterium bovis BCG, and overexpression of PTA in OCT313-resistant bacilli restored sensitivity to OCT313. Collectively, the target of OCT313 is PTA, and OCT313 is a promising antimicrobial candidate for MDR-TB and LTBI. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0301-679X 214 2026 The influence of lubricant additives and surface roughness and hardness of material on the damage behavior of gears 111341 EN Takuya Ohno Faculty of Environmental, Life, Natural Science and Technology, Okayama University Tadashi Shiota Faculty of Environmental, Life, Natural Science and Technology, Okayama University Masahiro Fujii Faculty of Environmental, Life, Natural Science and Technology, Okayama University This study investigates the influence of lubricant additives, surface roughness, and material hardness on gear damage behavior under boundary lubrication conditions. We conducted both the Short-term Test and the Standard Test using an FZG gear test machine to evaluate how lubricant additives and gear surface roughness influence damage progression when the surface roughness exceeds the oil-film thickness. Acid phosphate ester effectively suppressed micropitting through surface smoothing but led to severe damage such as pitting and scuffing during prolonged use. In contrast, sulfurized fatty oil promoted mild wear, delaying catastrophic failures and extending gear life. Higher surface roughness accelerated wear, while increased hardness reduced deformation but it expanded damage areas. The study found that initial surface roughness and its progress during load stages strongly correlate with gear durability. Measurement of arithmetic mean roughness after sufficient running-in under actual load conditions proved useful for predicting long-term performance. These findings highlight the importance of selecting lubricant formulations tailored to specific gear operating environments and damage modes. Understanding the interplay between lubrication chemistry and material properties enables the design of more durable gear systems. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2399-3669 8 1 2025 Synthesis of thienoacenes by electrochemical double C–S cyclization using a halogen mediator 366 EN Koichi Mitsudo Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takuya Nagahara Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nozomi Kataura Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuka Okamura Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Toki Yonezawa Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuri Tachibana Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nolan Soulié Faculty of Science and Engineering, Sorbonne Université Keisuke Shigemori Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Eisuke Sato Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hiroki Mandai Department of Pharmacy, Faculty of Pharmacy, Gifu University of Medical Science Seiji Suga Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Thienoacenes are significant compounds as organic materials. One of the most efficient ways to synthesize thienoacenes is to form multiple C–S bonds in a single step. Because unprotected S–H bonds are easily oxidized to S–S bonds, S-Me protected substrates are commonly used for the purpose. However, their reactivity is insufficient, and one-step construction of multiple C–S bonds is still challenging. We herein report the electrochemical synthesis of thienoacenes from S-methoxymethyl (MOM)-protected diarylacetylenes. In the presence of Bu4NBr as a halogen mediator, electrochemical double C–S cyclization of diarylacetylenes bearing two MOM groups proceeded to afford [1]benzothieno[3,2-b][1]benzothiophene (BTBT) derivatives. While S-Me or S-p-methoxybenzyl (PMB)-protected diarylacetylenes did not afford BTBT, BTBT was selectively obtained when a substrate protected with S-MOM groups was used. The S-MOM protection strategy is also effective for the electrochemical synthesis of a more π-expanded thienoacene such as dibenzo[d,d′]thieno[3,2-b,4,5-b′]dithiophene (DBTDT). No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1477-0520 23 43 2025 Harnessing the reactivity of captodative radicals: photocatalytic α-pyridination of glycyl derivatives through reversible radical coupling 9936 9941 EN Ken Yamazaki Division of Applied Chemistry, Okayama University Shuta Akimoto Division of Applied Chemistry, Okayama University Tomoya Miura Division of Applied Chemistry, Okayama University Captodative radicals that are highly stabilized by the presence of both electron-donating and electron-withdrawing groups exhibit unique reactivity in organic syntheses. These radicals are known to be less reactive towards radical–radical coupling reactions due to the presence of a shielding occupied molecular orbital. Herein we describe a photocatalytic synthetic strategy for the coupling of two different captodative radicals, which are generated from glycyl derivatives and 4-cyanopyridines. An aromatization is incorporated as the driving force after a reversible radical–radical coupling process. This method can be applied to a wide variety of peptides, providing pharmaceutically relevant pyridyl-functionalized products under mild reaction conditions. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-7345 61 68 2025 Revisiting 3-azidoindoles: overcoming the trade-off challenges between stability and reactivity of in situ-generated azidoindoles 12801 12804 EN Shota Asai School of Pharmacy, Shujitsu University Keisuke Tokushige Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takumi Abe Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University A concise protocol based on the E2 reaction of indoline hemiaminals for accessing 3-azidoindoles is reported. In contrast to previous methods that require in situ generation by hypervalent iodine reagents, our protocol allows for the isolation of a variety of 3-azidoindoles upon a mild reaction for a short reaction time at room temperature. The obtained 3-azidoindoles are reasonably reactive, bench-stable and easy to handle. These findings could be used as a starting point for various reactions, including Huisgen reaction, [3+2] cycloaddition, phosphoramidation, and cine-substitution with the release of N2. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1744-683X 21 43 2025 Effect of the pH value on compression and array structures of highly charged microgels at the air/water interface 8323 8333 EN Takahisa Kawamoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haruka Minato Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Daisuke Suzuki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Understanding the interfacial behavior of stimuli-responsive microgels is critical for applications such as foam and emulsion stabilization, as well as for the fabrication of two-dimensional colloidal crystals using the interfaces. In this study, the pH-dependent compression behavior and array structures of micron-sized poly(N-isopropylacrylamide-co-acrylic acid) microgels at the air/water interface was investigated. By combining a Langmuir trough with fluorescence microscopy, microgel arrays under compression and acidic (pH = 3) or basic (pH = 9) conditions were directly visualized. At pH = 9, the carboxyl groups within the microgels are deprotonated, resulting in significant swelling and the formation of ordered hexagonal arrays with high crystallinity (Ψ6 > 0.84) upon compression. In contrast, at pH = 3, the carboxyl groups within the microgels are protonated, leading to a suppression of the electrostatic repulsion between neighboring microgels and a reduction in crystallinity (Ψ6 ∼ 0.70) of the microgel arrays before and after compression. Furthermore, the calculated surface-compression modulus using the compression isotherms indicated higher interfacial elasticity for charged microgels, demonstrating that electrostatic repulsion governs both array ordering and mechanical robustness. These findings provide fundamental insights into the role of charge in controlling the microgel structure and mechanics at interfaces, thus offering further guidelines for the design of stimuli-responsive materials and stabilizers for foams and emulsions. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-7345 61 89 2025 The direct photochemical cross-esterification of alcohols via site-selective C–H bromination site-selective C–H bromination 17364 17367 EN 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 Research Institute for Interdisciplinary Science, Okayama University We have developed a direct photochemical cross-esterification of alcohols that proceeds via the in situ generation of acyl bromides. The C–H bond of a benzyl alcohol is selectively activated by a bromo source under light irradiation, enabling the cross-esterification to afford a variety of functionalized esters. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1477-0520 23 27 2025 Fluorescence detection of DNA with a single-base mismatch by a Tm-independent peptide nucleic acid (PNA) twin probe 6557 6563 EN Koki Ishii Department of Applied Chemistry, Kindai University Hajime Shigeto Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Shohei Yamamura Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Yoshitane Imai Department of Applied Chemistry, Kindai University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mizuki Kitamatsu Department of Applied Chemistry, Kindai University There is a need to develop efficient methods for detecting target nucleic acids to enable the rapid diagnosis and early treatment of diseases. We previously demonstrated that a peptide nucleic acid (PNA) twin probe, consisting of two PNAs each containing a fluorescent dye, with pyrene at one end, detects target DNA sequence-specifically through pyrene excimer emission. In this study, to advance the development of this probe system, we further investigated the fluorescence properties of the PNA twin probe P1 and P2, and found that the excimer fluorescence was significantly reduced when a mismatched base in the DNA sequence was present at the site of P1 closest to the pyrene. In other words, this probe was found to detect single-base mismatches without taking into account the thermal stability of the PNA/DNA hybrid. The detection limit of this PNA twin probe for the single-base-mismatched DNA was 2.7 nM. In the future, this probe should lead to a method to detect point mutations in endogenous nucleic acids within cells. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2398-4902 2025 Activation of barium titanate for photocatalytic overall water splitting via low-valence cation codoping EN Shigeru Ikeda Faculty of Science and Engineering, Konan University Kaori Takagi Faculty of Science and Engineering, Konan University Ryota Tomizawa Carbon Neutral Energy Development Division, Toyota Motor Corporation Tomoya Nagano Carbon Neutral Energy Development Division, Toyota Motor Corporation Koji Hayashi Carbon Neutral Energy Development Division, Toyota Motor Corporation Akira Yamakata Research Institute for Interdisciplinary Science, Okayama University Yoshitaro Nose Department of Materials Science and Engineering, Kyoto University Barium titanate (BaTiO3) has long been regarded as inactive for photocatalytic overall water splitting, in stark contrast to its perovskite counterparts SrTiO3 and CaTiO3. Here we report that BaTiO3 codoped with Al3+ and Sc3+ at Ti4+ sites under flux synthesis conditions is activated as a robust photocatalyst for overall water splitting. This material achieves apparent quantum yields of 29.8% at 310 nm and 27.5% at 365 nm, representing the first demonstration of efficient overall water splitting on BaTiO3. Comparative analyses show that BaTiO3 doped only with Al3+ suffers from severe band-edge disorder, whereas BaTiO3 codoped with Al3+ and Mg2+ exhibits clear activation with moderate efficiency. In contrast, BaTiO3 codoped with Al3+ and Sc3+ achieves the critical defect and structural control required to push the material across the threshold from inactive to highly active. These findings overturn the long-standing perception of BaTiO3 as unsuitable for water splitting and establish a general design principle for activating previously inactive perovskite oxides, thereby expanding the materials palette for solar-to-hydrogen energy conversion. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0921-8831 36 10 2025 Evaluating the effects of electrolytes on the interaction forces between alumina surfaces in polyacrylic acid solutions using atomic force microscopy 105028 EN Naoto Kishimoto Graduate School of Natural Science and Technology, Okayama University Ryota Kaji Faculty of Science and Engineering, Doshisha University Katsumi Tsuchiya Faculty of Science and Engineering, Doshisha University Koreyoshi Imamura Graduate School of Natural Science and Technology, Okayama University Naoyuki Ishida Faculty of Science and Engineering, Doshisha University Evaluation and control of ceramic slurry at the microscopic level are critical to ensure consistent quality in manufactured ceramics. Notably, metal ions such as Mg2+ and Al3+ are common in ceramic slurries and significantly influence the stability of particle. This study applied atomic force microscopy to investigate the interaction forces between alumina particle surfaces in the presence of different concentrations of three metal ions and polyacrylic acid (PAA), a widely used dispersant. The attractive forces observed at low PAA concentrations were attributed to polymer bridging between alumina surfaces, whereas the repulsive forces observed at high PAA concentrations were attributed to the domination of steric repulsion between adsorbed PAA molecules. The presence of multivalent metal ions, such as Mg2+ and Al3+, modulated these interactions; an increasing ion valence induced a transition from repulsive to attractive force, primarily owing to electrostatic screening, which caused conformational collapse of the PAA chains and diminished the range of steric repulsion. Similarly, increasing the concentration of these metal ions decreased the range of repulsive forces, eventually resulting in a net attraction driven by the same electrostatic and polymer conformation mechanisms. Notably, the addition of 0.1 M AlCl3 produced an anomalous long-range attraction between surfaces that could not be explained by conventional mechanisms, such as polymer bridging or electrostatic interactions between charge domains. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2041-1723 16 1 2025 Persistent homology elucidates hierarchical structures responsible for mechanical properties in covalent amorphous solids 8226 EN Emi Minamitani SANKEN, The University of Osaka Takenobu Nakamura Department of Materials and Chemistry Materials DX Research Center, National Institute of Advanced Industrial Science and Technology (AIST) Ippei Obayashi Center for Artificial Intelligence and Mathematical Data Science, Okayama University Hideyuki Mizuno Graduate School of Arts and Sciences, The University of Tokyo Understanding how atomic-level structures govern the mechanical properties of amorphous materials remains a fundamental challenge in solid-state physics. Under mechanical loading, amorphous materials exhibit simple affine and spatially inhomogeneous nonaffine displacements that contribute to the elastic modulus through the Born (affine) and nonaffine terms, respectively. The differences between soft local structures characterized by small Born terms or large nonaffine displacements have yet to be elucidated. This challenge is particularly complex in covalent amorphous materials such as silicon, where the medium-range order (MRO) plays a crucial role in the network structure. To address these issues, we combined molecular dynamics simulations with persistent homology analysis. Our results reveal that local structures with small Born terms are governed by short-range characteristics, whereas those with large nonaffine displacements exhibit hierarchical structures in which short-range disorder is embedded within the MRO. These hierarchical structures are also strongly correlated with low-energy localized vibrational excitations. Our findings demonstrate that the mechanical responses and dynamic properties of covalent amorphous materials are intrinsically linked to the MRO, providing a framework for understanding and tailoring their properties. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2045-2322 15 1 2025 Pharmacokinetics and the effectiveness of pyrogen-free bioabsorbable wet adhesives 20056 EN Risa Oshima Department of Periodontology, Faculty of Dental Medicine, Hokkaido University Kumiko Yoshihara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ko Nakanishi Department of Biomaterials and Bioengineering, Faculty of Dental Medicine, Hokkaido University Tsukasa Akasaka Department of Biomaterials and Bioengineering, Faculty of Dental Medicine, Hokkaido University Shinji Shimoji Department of Periodontology, Faculty of Dental Medicine, Hokkaido University Teppei Nakamura Department of Applied Veterinary Science, Faculty of Veterinary Medicine, Hokkaido University Takumi Okihara Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Mariko Nakamura Department of Clinical Psychology, School of Clinical Psychology, Kyushu University of Medical and Science Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ikkei Tamada Department of Plastic and Reconstructive Surgery, Tokyo Metropolitan Children’s Medical Center Bart Van Meerbeek BIOMAT, Department of Oral Health Sciences, & UZ Leuven, Dentistry, KU Leuven Tsutomu Sugaya Department of Periodontology, Faculty of Dental Medicine, Hokkaido University Yasuhiro Yoshida Department of Biomaterials and Bioengineering, Faculty of Dental Medicine, Hokkaido University Bioabsorbable materials are essential for advanced therapies, including surgical sealing, cell therapy, and drug delivery. Natural bioabsorbable materials, including collagen and hyaluronic acid, have better biocompatibility than synthetic bioabsorbable polymers; however, they are mainly derived from animals, presenting infection risks. Non-animal origin polymers have a lower molecular weight than those of animal origins. Their viscosity increases with increase in molecular weight, making endotoxin removal difficult. Here, using the phosphoryl chloride disposal method, we present a strategy for synthesizing pyrogen-free bioabsorbable adhesives with controlled molecular weight. Phosphopullulan, a polysaccharide derivative, had less than detectable endotoxin levels and controllable average molecular weight of approximately 300,000 to over 1,400,000. Furthermore, it is important to ensure the safety as well as efficacy of bio-implantable materials. We have evaluated the biosafety of polysaccharide derivatives we are developing, and have examined their cell phagocytosis and pharmacokinetics in vitro and in vivo, and have confirmed that they are safe. We have also evaluated their adhesion to wet tissue adhesions and confirmed that they leak less than existing materials. No potential conflict of interest relevant to this article was reported.

American Association for the Advancement of Science (AAAS) Acta Medica Okayama 2375-2548 11 38 2025 Polymeric microwave rectifiers enabled by monolayer-thick ionized donors eadv9952 EN Nobutaka Osakabe Material Innovation Research Center (MIRC) and Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo Jeongeun Her Material Innovation Research Center (MIRC) and Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo Takahiro Kaneta Material Innovation Research Center (MIRC) and Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo Akiko Tajima Material Innovation Research Center (MIRC) and Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo Elena Longhi School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology Kan Tang Renewable and Sustainable Energy Institute, University of Colorado Boulder Kazuhiro Fujimori Faculty of Environmental, Life, Natural Science and Technology, Okayama University Stephen Barlow School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology Seth R. Marder School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology Shun Watanabe Material Innovation Research Center (MIRC) and Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo Jun Takeya Material Innovation Research Center (MIRC) and Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo Yu Yamashita Material Innovation Research Center (MIRC) and Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo Solution processing of polymeric semiconductors provides a facile way to fabricate functional diodes. However, energy barriers at metal-semiconductor interfaces often limit their performance. Here, we report rectifying polymer diodes with markedly modified energy-level alignments. The gold electrode surface was treated with a dimeric metal complex, which resulted in a shallow work function of 3.7 eV by forming a monolayer-thick ionized donor layer. When a polymeric semiconductor was coated on the treated electrode, most of the ionized donors remained at the metal-semiconductor interface. The confined ionized donors with the ideal thickness enabled fabrication of a polymer diode with a forward current density of over 100 A cm－2. Furthermore, a power conversion efficiency of 7.9% was observed for rectification at a microwave frequency of 920 MHz, which is orders of magnitude higher than that reported for organic diodes. Our findings will pave a way to solution-processed high-frequency and high-power devices. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1472-6831 25 1 2025 Phosphorylated pullulan as a local drug delivery matrix for cationic antibacterial chemicals to prevent oral biofilm 1333 EN Naoko Namba-Koide Department of Periodontics and Endodontics, Division of Dentistry, Okayama University Hospital Yasuhiro Yoshida Department of Biomaterials and Bioengineering, Faculty of Dental Medicine, Hokkaido University Noriyuki Nagaoka Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School Takumi Okihara Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Yusuke Kawata Department of Periodontics and Endodontics, Division of Dentistry, Okayama University Hospital Masahiro Ito Department of Periodontics and Endodontics, Division of Dentistry, Okayama University Hospital Takashi Ito Center for Innovative Clinical Medicine, Okayama University Hospital Kazu Takeuchi-Hatanaka Department of Periodontics and Endodontics, Division of Dentistry, Okayama University Hospital Yuki Shinoda-Ito Department of Pathophysiology - Periodontal Science, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kazuhiro Omori Department of Pathophysiology - Periodontal Science, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tadashi Yamamoto Department of Pathophysiology - Periodontal Science, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shogo Takashiba Department of Pathophysiology - Periodontal Science, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Background Preventing oral infections, such as oral caries and periodontal disease, helps reduce the risks of various systemic diseases. In this study, the polysaccharide pullulan produced by the black yeast Aureobasidium pullulans was modified in combination with the cationic surfactant cetylpyridinium chloride (CPC) to create a local drug delivery system, and its antibacterial potential on oral bacteria was examined in vitro. Methods Pullulan was phosphorylated at the CH2OH residue of α6 in the maltotriose structure and mixed with CPC. Bacterial attachment of cariogenic Streptococcus mutans on hydroxyapatite plates (HAPs) treated with the phosphorylated pullulan (PP) and CPC compound (0.01% PP and 0.001– 0.03% CPC, and vice versa) was assessed by observing bacteria using a field emission scanning electron microscope (FE-SEM) and quantified through 16 S rRNA amplification via real-time polymerase chain reaction (PCR). Additionally, the quartz crystal microbalance (QCM) method was employed to evaluate the sustained release of CPC. Results PP-CPC compound maintained significant bactericidal activity even at 0.01%, which is one-fifth of the conventional applicable concentration of CPC. Additionally, a residual mixture was detected by the hydroxyapatite sensor of the crystal oscillator microbalance detector, suggesting an unknown molecular interaction that enables the sustained release of CPC after attachment to hydroxyapatite. Conclusions The combination of PP and CPC may contribute to the low concentration and effective prevention of oral infections, such as dental caries. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2050-7488 13 35 2025 Thermally polymerizable phthalocyanine realizes a metal–nitrogen-doped carbon material featuring a defined single-atom catalyst motif with CO2RR activity 28887 28895 EN Yuki Sano Department of Chemistry, Graduate School of Science, Tohoku University Daichi Nakajima Department of Chemistry, Graduate School of Science, Tohoku University Biplab Manna Center for Basic Research on Materials, National Institute for Materials Science Koki Chida Institute of Multidisciplinary Research for Advanced Materials, Tohoku University Ryojun Toyoda Department of Chemistry, Graduate School of Science, Tohoku University Shinya Takaishi Department of Chemistry, Graduate School of Science, Tohoku University Kazuyuki Iwase Institute of Multidisciplinary Research for Advanced Materials, Tohoku University Koji Harano Center for Basic Research on Materials, National Institute for Materials Science Yuta Nishina Graduate School of Natural Science and Technology, Okayama University Takeharu Yoshii Institute of Multidisciplinary Research for Advanced Materials, Tohoku University Ryota Sakamoto Department of Chemistry, Graduate School of Science, Tohoku University Metal–nitrogen-doped carbon materials (MNCs) exhibit good electrocatalytic performance owing to the intrinsic advantages of carbon-based materials and the presence of isolated and stabilized metal atoms coordinated by nitrogen sites. However, conventional high-temperature pyrolysis of precursor molecules make it difficult to control the coordination structure precisely. To address this issue, here we report a new synthesis strategy for MNCs. Specifically, we design and synthesize Ni-phthalocyanine functionalized with ethynyl groups as solid-state thermal polymerization points. After depositing the Ni-phthalocyanine precursor on a carbon support and performing a thermal treatment, the resultant carbon composite material features a Ni–N4 coordination structure derived from the precursor, and enhanced porosity. This material demonstrates high catalytic activity for the CO2 reduction reaction (CO2RR). Our synthetic approach is applicable to various precursor molecules and carbon supports, paving the way for the further development of MNC-based electrode catalysts. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2399-3669 7 1 2024 Post-spinel-type AB2O4 high-pressure phases in geochemistry and materials science 189 EN Masaki Akaogi Department of Chemistry, Gakushuin University Takayuki Ishii Institute for Planetary Materials, Okayama University Kazunari Yamaura Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science Post-spinel-type AB2O4 compounds are stable at higher pressures than spinel phases. These compounds have garnered much interest in geo- and materials science for their geochemical importance as well as potential application as high ionic conductors and materials with strongly correlated electrons. Here, large-volume high-pressure syntheses, structural features and properties of post-spinels are reviewed. Prospects are discussed for future searches for post-spinel-type phases by applying advanced large-volume high-pressure technology. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 1660-3397 23 5 2025 Novel Anti-MRSA Peptide from Mangrove-Derived Virgibacillus chiguensis FN33 Supported by Genomics and Molecular Dynamics 209 EN Namfa Sermkaew School of Pharmacy, Walailak University Apichart Atipairin School of Pharmacy, Walailak University Phetcharat Boonruamkaew 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 Bacteriology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yodying Yingchutrakul National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency Nuttapon Songnaka School of Pharmacy, Walailak University Antimicrobial resistance (AMR) is a global health threat, with methicillin-resistant Staphylococcus aureus (MRSA) being one of the major resistant pathogens. This study reports the isolation of a novel mangrove-derived bacterium, Virgibacillus chiguensis FN33, as identified through genome analysis and the discovery of a new anionic antimicrobial peptide (AMP) exhibiting anti-MRSA activity. The AMP was composed of 23 amino acids, which were elucidated as NH3-Glu-Gly-Gly-Cys-Gly-Val-Asp-Thr-Trp-Gly-Cys-Leu-Thr-Pro-Cys-His-Cys-Asp-Leu-Phe-Cys-Thr-Thr-COOH. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for MRSA were 8 µg/mL and 16 µg/mL, respectively. FN33 AMP induced cell membrane permeabilization, suggesting a membrane-disrupting mechanism. The AMP remained stable at 30–40 °C but lost activity at higher temperatures and following exposure to proteases, surfactants, and extreme pH. All-atom molecular dynamics simulations showed that the AMP adopts a β-sheet structure upon membrane interaction. These findings suggest that Virgibacillus chiguensis FN33 is a promising source of novel antibacterial agents against MRSA, supporting alternative strategies for drug-resistant infections. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2694-2496 2025 RNA Delivery Using a Graphene Oxide-Polyethylenimine Hybrid Inhibiting Myotube Differentiation EN Koji Matsuura CNRS, Immunology, Immunopathology and Therapeutic Chemistry, UPR3572, University of Strasbourg, ISIS Giacomo Reina CNRS, Immunology, Immunopathology and Therapeutic Chemistry, UPR3572, University of Strasbourg, ISIS Zhengfeng Gao CNRS, Immunology, Immunopathology and Therapeutic Chemistry, UPR3572, University of Strasbourg, ISIS Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Alberto Bianco CNRS, Immunology, Immunopathology and Therapeutic Chemistry, UPR3572, University of Strasbourg, ISIS Graphene oxide (GO) conjugated with short polyethylenimine (PEI) chains (GO-PEI) has been designed as a candidate nanocarrier for small interfering RNA (siRNA) delivery to mammalian cells based on the efficient interaction between the positively charged GO-based platform and the negatively charged siRNA. The function and efficiency of siRNA delivery using GO-PEI were compared to those using the positive control Lipofectamine RNAiMax by analyzing the differentiation to myotubes, and myogenin gene and protein expression in C2C12 cells. RNAiMax transfection induced cellularization and reduction of both myogenin gene and protein expression, suggesting that the differentiation of C2C12 cells was triggered by gene silencing. While GO-PEI also promoted cellularization, the myogenin gene expression remained comparable to scrambled controls, whereas the protein levels were higher than those observed with RNAiMax. Mechanistically, we attributed the reduced gene silencing efficiency of GO-PEI to a poor endosomal escape, despite strong siRNA complexation. This limitation was likely due to a low buffering capacity of GO-PEI, as a significant fraction of nitrogen atoms were already protonated, reducing the availability of free amines necessary for endosomal disruption. An appropriate chemical modification to enhance siRNA release from the endosomes is therefore essential for advancing the development of GO-based platforms as versatile and efficient nanocarriers in gene therapy applications. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2079-6382 13 9 2024 Unveiling a New Antimicrobial Peptide with Efficacy against P. aeruginosa and K. pneumoniae from Mangrove-Derived Paenibacillus thiaminolyticus NNS5-6 and Genomic Analysis 846 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 Bacteriology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Nuttapon Songnaka School of Pharmacy, Walailak University This study focused on the discovery of the antimicrobial peptide (AMP) derived from mangrove bacteria. The most promising isolate, NNS5-6, showed the closest taxonomic relation to Paenibacillus thiaminolyticus, with the highest similarity of 74.9%. The AMP produced by Paenibacillus thiaminolyticus NNS5-6 exhibited antibacterial activity against various Gram-negative pathogens, especially Pseudomonas aeruginosa and Klebsiella pneumoniae. The peptide sequence consisted of 13 amino acids and was elucidated as Val-Lys-Gly-Asp-Gly-Gly-Pro-Gly-Thr-Val-Tyr-Thr-Met. The AMP mainly exhibited random coil and antiparallel beta-sheet structures. The stability study indicated that this AMP was tolerant of various conditions, including proteolytic enzymes, pH (1.2–14), surfactants, and temperatures up to 40 °C for 12 h. The AMP demonstrated 4 µg/mL of MIC and 4–8 µg/mL of MBC against both pathogens. Time-kill kinetics showed that the AMP acted in a time- and concentration-dependent manner. A cell permeability assay and scanning electron microscopy revealed that the AMP exerted the mode of action by disrupting bacterial membranes. Additionally, nineteen biosynthetic gene clusters of secondary metabolites were identified in the genome. NNS5-6 was susceptible to various commonly used antibiotics supporting the primary safety requirement. The findings of this research could pave the way for new therapeutic approaches in combating antibiotic-resistant pathogens. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-7345 2025 Generation of alkyl radicals via C(sp3)–C(sp3) bond cleavage of xanthene-based precursors for photocatalytic Giese-type reaction EN Shuta Horiuchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Masato Oishi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Asuka Mizutani 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 Research Institute for Interdisciplinary Science, Okayama University Novel xanthene-based alkyl radical precursors were developed and subjected to photocatalytic C(sp3)–C(sp3) bond cleavage for the efficient generation of alkyl radicals, which were subsequently reacted with various alkenes to afford the corresponding Giese-type products. After the reaction, the produced xanthones can be recovered in high yield. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0969-806X 239 2026 Helical X-ray tube trajectory estimation via image noise analysis for enhanced CT dosimetry 113260 EN Tatsuya Maeda Graduate School of Medical Sciences, Kanazawa University Kazuki Takegami Department of Radiological Technology, Yamaguchi University Hospital Sota Goto Faculty of Health Sciences, Kobe Tokiwa University Takashi Asahara Department of Radiological Technology, Faculty of Health Sciences, Okayama University Daiki Kobayashi Graduate School of Medical Sciences, Kanazawa University Rina Nishigami Graduate School of Medical Sciences, Kanazawa University Natsumi Kimoto Department of Radiological Science, Faculty of Health Sciences, Junshin Gakuen University Kazuta Yamashita Department of Orthopedics, School of Medicine, Tokushima University Kosaku Higashino Shikoku Medical Center for Children and Adults Shinichi Morimoto MEDITEC JAPAN Co., Ltd., Yamaguchi Kosan Bld. Takeshi Konishi MEDITEC JAPAN Co., Ltd., Yamaguchi Kosan Bld. Motochika Maki MEDITEC JAPAN Co., Ltd., Yamaguchi Kosan Bld. Hiroaki Hayashi College of Transdisciplinary Sciences for Innovation, Kanazawa University Information on the helical trajectory of the X-ray tube is necessary for accurate dose evaluation during computed tomography (CT). We aimed to propose a methodology for analyzing the trajectory of the X-ray tube. The novelty of this paper is that the incident direction of X-rays is estimated from the standard deviation (SD) distribution. The X-ray incident direction for each slice was analyzed using a distribution function of SD values, in which the analysis regions were placed in the air region. Then, the helical trajectory of the CT scan was estimated by fitting a three-dimensional helical function to the analyzed data. The robustness of our algorithm was verified through phantom studies: the analyzed X-ray incident directions were compared with instrumental log data, in which cylindrical polyoxymethylene resin phantoms and a whole-body phantom were scanned. Chest CT scanning was mimicked, in which the field of view (FOV) was set at the lung region. The procedure for analyzing the X-ray incident direction was applicable to cylindrical phantoms regardless of the phantom size. In contrast, in the case of the whole-body phantom, although it was possible to apply our procedure to the chest and abdomen regions, the shoulder slices were inappropriate to analyze. Therefore, the helical trajectory was determined based on chest and abdominal CT images. The accuracy in X-ray incident direction analysis was evaluated to be 7.5°. In conclusion, we have developed an algorithm to estimate a three-dimensional helical trajectory that can be used for dose measurements and simulations. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0024-9297 58 3 2025 Synthesis and Postfunctionalization of Acrylate-Appended Poly(cyclohexene carbonate)s: Modulation of Properties of CO2-Based Polymers 1571 1577 EN Chihiro Maeda Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Hina Inoue Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Tadashi Ema Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Functional CO2-based polycarbonates are expected to be sustainable materials. Herein, a bifunctional aluminum porphyrin catalyzed the terpolymerization of cyclohexene oxide (CHO), acrylate-appended CHO, and CO2 to provide poly(cyclohexene carbonate)s (PCHCs) with acrylate groups. Postfunctionalization of PCHCs via Michael addition or Heck reaction enabled the incorporation of thiol, amine, and aromatics into PCHCs with high selectivity and efficiency. PCHCs with the flexible long alkyl chains showed a glass-transition temperature (Tg) of down to 52 °C, which was much lower than that of PCHC (127 °C). In sharp contrast, PCHCs with rigid pyrenyl groups showed Tg values of up to 152 °C and fluorescence emission. Thus, a wide range of polymers were obtained by robust and sustainable synthetic methods, and the functional groups modulated the properties of the CO2-based polycarbonates. No potential conflict of interest relevant to this article was reported.

Oxford University Press (OUP) Acta Medica Okayama 0009-2673 98 6 2025 Redox-potential-controlled intermolecular [2 + 2] cycloaddition of styrenes for the regio- and diastereoselective synthesis of multisubstituted halogenocyclobutanes uoaf044 EN Asuka Mizutani Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Momo Kondo Laboratory of Biopharmaceutics, Faculty of Pharmaceutical Sciences, Tokyo University of Science Shoko Itakura Laboratory of Biopharmaceutics, Faculty of Pharmaceutical Sciences, Tokyo University of Science Hiroyoshi Takamura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yujiro Hoshino Graduate School of Environment and Information Sciences, Yokohama National University Makiya Nishikawa Laboratory of Biopharmaceutics, Faculty of Pharmaceutical Sciences, Tokyo University of Science Isao Kadota Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kosuke Kusamori Laboratory of Cellular Drug Discovery and Development, Faculty of Pharmaceutical Sciences, Tokyo University of Science Kenta Tanaka Research Institute for Interdisciplinary Science, Okayama University The redox potential is an important factor for controlling the outcome of photoredox catalysis. Particularly, the selective oxidation of substrates and the control over the reactions are challenging when using photoredox catalysts that have high excited-state reduction potentials. In this study, a redox-potential-controlled intermolecular [2 + 2] cycloaddition of styrenes using a thioxanthylium organophotoredox (TXT) catalyst has been developed. This TXT catalyst selectively oxidizes β-halogenostyrenes and smoothly promotes the subsequent intermolecular [2 + 2] cycloadditions to give multisubstituted halogenocyclobutanes with excellent regio- and diastereoselectivity, which has not been effectively achieved by the hitherto reported representative photoredox catalysts. The synthesized halogenocyclobutanes exhibit interesting free radical scavenging activity. The present reaction contributes to the field of redox-potential-controlled electron transfer chemistry. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0360-3199 140 2025 Advances in filler-crosslinked membranes for hydrogen fuel cells in sustainable energy generation 745 776 EN Aminul Islam Department of Petroleum and Mining Engineering, Jashore University of Science and Technology Mamun Shahriar Department of Petroleum and Mining Engineering, Jashore University of Science and Technology Md. Tarekul Islam Department of Leather Engineering, Faculty of Mechanical Engineering, Khulna University of Engineering and Technology Siow Hwa Teo Industrial Chemistry Program, Faculty of Science and Natural Resources, Universiti Malaysia Sabah M. Azizur R. Khan Department of Chemistry, Jashore University of Science and Technology Yun Hin Taufiq-Yap Catalysis Science and Technology Research Centre, Faculty of Science, Universiti Putra Malaysia Suman C. Mohanta Department of Chemistry, Jashore University of Science and Technology Ariyan Islam Rehan Department of Chemistry, School of Science, The University of Tokyo Adiba Islam Rasee Department of Chemistry, Graduate School of Science, Osaka University Khadiza Tul Kubra Department of Chemistry, Graduate School of Science, Osaka University Md. Munjur Hasan Department of Chemistry, Graduate School of Science, Osaka University Md. Shad Salman Institute for Chemical Research, Kyoto University R.M. Waliullah Institute for Chemical Research, Kyoto University Md. Nazmul Hasan Department of Chemistry, School of Science, The University of Tokyo Md. Chanmiya Sheikh Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Tetsuya Uchida Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Mrs Eti Awual Institute for Chemical Research, Kyoto University Mohammed Sohrab Hossain Department of Chemistry, Graduate School of Science, Osaka University Hussein Znad Western Australian School of Mines: Minerals, Energy and Chemical Engineering, Curtin University Md. Rabiul Awual Western Australian School of Mines: Minerals, Energy and Chemical Engineering, Curtin University Fuel cell membranes can be used in various ways to achieve zero-emission transport and energy systems, which offer a promising way to power production due to their higher efficiency compared to the internal combustion engine and the eco-environment. Perfluoro sulfonic acid membranes used for proton exchange membranes (PEMs) have certain drawbacks, like higher fuel permeability and expense, lower mechanical and chemical durability, and proton conductivity under low humidity and above 80 °C temperature. Researchers have drawn their attention to the production of polymer electrolyte membranes with higher proton conductivity, thermal and chemical resilience, maximum power density, lower fuel permeability, and lower expense. For sustainable clean energy generation, a review covering the most useful features of advanced material-associated membranes would be of great benefit to all interested communities. This paper endeavors to explore several types of novel inorganic fillers and crosslinking agents, which have been incorporated into membrane matrices to design the desired properties for an advanced fuel cell system. Membrane parameters such as proton conductivity, the ability of H2 transport, and the stability of the membrane are described. Research directions for developing fuel cell membranes are addressed based on several challenges suggested. The technological advancement of nanostructured materials for fuel cell applications is believed to significantly promote the future clean energy generation technology in practice. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0360-3199 101 2025 Next frontier in photocatalytic hydrogen production through CdS heterojunctions 173 211 EN Aminul Islam Department of Petroleum and Mining Engineering, Jashore University of Science and Technology Abdul Malek Department of Petroleum and Mining Engineering, Jashore University of Science and Technology Md. Tarekul Islam Department of Leather Engineering, Faculty of Mechanical Engineering, Khulna University of Engineering and Technology Farzana Yeasmin Nipa Department of Petroleum and Mining Engineering, Jashore University of Science and Technology Obayed Raihan Department of Pharmaceutical Sciences, College of Health Sciences and Pharmacy, Chicago State University Hasan Mahmud Bangladesh Energy and Power Research Council (BEPRC) Md. Elias Uddin Department of Leather Engineering, Faculty of Mechanical Engineering, Khulna University of Engineering and Technology Mohd Lokman Ibrahim School of Chemistry and Environment, Faculty of Applied Sciences, Universiti Teknologi MARA G. Abdulkareem-Alsultan Catalysis Science and Technology Research Centre, Faculty of Science, Universiti Putra Malaysia Alam Hossain Mondal USAID - Bangladesh Advancing Development and Growth through Energy (BADGE) Project, Tetra Tech Md. Munjur Hasan Department of Chemistry, Graduate School of Science, Osaka University Md. Shad Salman Institute for Chemical Research, Kyoto University Khadiza Tul Kubra Department of Chemistry, Graduate School of Science, Osaka University Md. Nazmul Hasan Department of Chemistry, School of Science, The University of Tokyo Md. Chanmiya Sheikh Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Tetsuya Uchida Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Adiba Islam Rasee Department of Chemistry, Graduate School of Science, Osaka University Ariyan Islam Rehan Department of Chemistry, School of Science, The University of Tokyo Mrs Eti Awual Institute for Chemical Research, Kyoto University Mohammed Sohrab Hossain Department of Chemistry, Graduate School of Science, Osaka University R.M. Waliullah Institute for Chemical Research, Kyoto University Md. Rabiul Awual Western Australian School of Mines: Minerals, Energy and Chemical Engineering, Curtin University Photocatalytic hydrogen (H₂) generation via solar-powered water splitting represents a sustainable solution to the global energy crisis. Cadmium sulfide (CdS) has emerged as a promising semiconductor photocatalyst due to its tunable bandgap, high physicochemical stability, cost-effectiveness, and widespread availability. This review systematically examines recent advancements in CdS-based heterojunctions, categorized into CdS-metal (Schottky), CdS-semiconductor (p-n, Z-scheme, S-scheme), and CdS-carbon heterojunctions. Various strategies employed to enhance photocatalytic efficiency and stability are discussed, including band structure engineering, surface modification, and the incorporation of crosslinked architectures. A critical evaluation of the underlying photocatalytic mechanisms highlights recent efforts to improve charge separation and photostability under operational conditions. This review highlights the challenges and opportunities in advancing CdS-based photocatalysts and provides a direction for future research. The insights presented aim to accelerate the development of efficient and durable CdS-based photocatalysts for sustainable H₂ production. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0001-8686 343 2025 Progress in silicon-based materials for emerging solar-powered green hydrogen (H2) production 103558 EN Aminul Islam Department of Petroleum and Mining Engineering, Jashore University of Science and Technology Md. Tarekul Islam Department of Leather Engineering, Faculty of Mechanical Engineering, Khulna University of Engineering and Technology Siow Hwa Teo Industrial Chemistry Program, Faculty of Science and Natural Resources, Universiti Malaysia Sabah Hasan Mahmud Bangladesh Energy and Power Research Council (BEPRC) A.M. Swaraz Department of Genetic Engineering and Biotechnology, Jashore University of Science and Technology Ariyan Islam Rehan Department of Chemistry, School of Science, The University of Tokyo Adiba Islam Rasee Department of Chemistry, Graduate School of Science, Osaka University Khadiza Tul Kubra Department of Chemistry, Graduate School of Science, Osaka University Md. Munjur Hasan Department of Chemistry, Graduate School of Science, Osaka University Md. Shad Salman Institute for Chemical Research, Kyoto University R.M. Waliullah Institute for Chemical Research, Kyoto University Md. Nazmul Hasan Department of Chemistry, School of Science, The University of Tokyo Md. Chanmiya Sheikh Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Tetsuya Uchida Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Mrs Eti Awual Department of Chemistry, Graduate School of Science, Osaka University Mohammed Sohrab Hossain Department of Chemistry, Graduate School of Science, Osaka University Hussein Znad Western Australian School of Mines: Minerals, Energy and Chemical Engineering, Curtin University Md. Rabiul Awual Western Australian School of Mines: Minerals, Energy and Chemical Engineering, Curtin University The imperative demand for sustainable and renewable energy solutions has precipitated profound scientific investigations into photocatalysts designed for the processes of water splitting and hydrogen fuel generation. The abundance, low toxicity, high conductivity, and cost-effectiveness of silicon-based compounds make them attractive candidates for hydrogen production, driving ongoing research and technological advancements. Developing an effective synthesis method that is simple, economically feasible, and environmentally friendly is crucial for the widespread implementation of silicon-based heterojunctions for sustainable hydrogen production. Balancing the performance benefits with the economic and environmental considerations is a key challenge in the development of these systems. The specific performance of each catalyst type can vary depending on the synthesis method, surface modifications, catalyst loading, and reaction conditions. The confluence of high crystallinity, reduced oxygen concentration, and calcination temperature within the silicon nanoparticle has significantly contributed to its noteworthy hydrogen evolution rate. This review provides an up-to-date evaluation of Si-based photocatalysts, summarizing recent developments, guiding future research directions, and identifying areas that require further investigation. By combining theoretical insights and experimental findings, this review offers a comprehensive understanding of Si-based photocatalysts for water splitting. Through a comprehensive analysis, it aims to elucidate existing knowledge gaps and inspire future research directions towards optimized photocatalytic performance and scalability, ultimately contributing to the realization of sustainable hydrogen generation. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0009-4536 2025 Elucidation of the relationship between solid‐state photoluminescence and crystal structures in 2,6‐substituted naphthalene derivatives EN Minoru Yamaji Department of Applied Chemistry, Division of Materials and Environment, Graduate School of Science and Engineering, Gunma University Isao Yoshikawa Department of Materials and Environmental Science, Institute of Industrial Science, The University of Tokyo Toshiki Mutai Technology Transfer Service Corporation Hirohiko Houjou Department of Materials and Environmental Science, Institute of Industrial Science, The University of Tokyo Kenta Goto Institute for Materials Chemistry and Engineering, Kyushu University Fumito Tani Institute for Materials Chemistry and Engineering, Kyushu University Kengo Suzuki Hamamatsu Photonics K.K Hideki Okamoto Department of Chemistry, Faculty of Environment, Life, Natural Sciences and Technology, Okayama University Polycyclic aromatic hydrocarbons (PAHs) are known to exhibit fluorescence in solution, but generally do not emit in the solid state, with the notable exception of anthracene. We previously reported that PAHs containing multiple chromophores show solid-state emission, and we have investigated the relationship between their crystal structures and photoluminescence properties. In particular, PAHs with herringbone-type crystal packing, such as 2,6-diphenylnaphthalene (DPhNp), which has a slender and elongated molecular structure, exhibits red-shifted solid-state fluorescence spectra relative to their solution-phase counterparts. In this study, we synthesized 2,6-naphthalene derivatives bearing phenyl and/or pyridyl substituents (PhPyNp and DPyNp) and observed distinct, red-shifted emission in the solid state compared with that in solution. Crystallographic analysis revealed that both PhPyNp and DPyNp adopt herringbone packing motifs. These findings support our hypothesis that the spectral characteristics of PAH emission are closely linked to crystal packing arrangements, providing a useful strategy for screening PAH candidates for applications in organic semiconducting materials. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2079-6447 3 4 2024 N-Phenylphenothiazine Radical Cation with Extended π-Systems: Enhanced Heat Resistance of Triarylamine Radical Cations as Near-Infrared Absorbing Dyes 350 359 EN Masafumi Yano Faculty of Chemistry, Material and Bioengineering, Kansai University Minami Ueda Faculty of Chemistry, Material and Bioengineering, Kansai University Tatsuo Yajima 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 N-Phenylphenothiazine derivatives extended with various aryl groups were designed and synthesized. These derivatives have bent conformation in crystal and exhibit high solubility. Radical cations obtained by one-electron oxidation of these derivatives gave stable radical cations in solution and showed absorption in the near-infrared region. A radical cation was isolated as a stable salt, which exhibited heat resistance up to around 200 °C. A design strategy for radical cation-based near-infrared absorbing dyes, which are easily oxidized and stable not only as a solution but in solid form, is described. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2691-3704 5 2 2025 Mechanistic Insights Into Oxidative Response of Heat Shock Factor 1 Condensates 606 617 EN Soichiro Kawagoe Institute of Advanced Medical Sciences, Tokushima University Motonori Matsusaki Institute of Advanced Medical Sciences, Tokushima University Takuya Mabuchi Frontier Research Institute for Interdisciplinary Sciences, Tohoku University Yuto Ogasawara Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kazunori Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Koichiro Ishimori Department of Chemistry, Faculty of Science, Hokkaido University Tomohide Saio Institute of Advanced Medical Sciences, Tokushima University Heat shock factor 1 (Hsf1), a hub protein in the stress response and cell fate decisions, senses the strength, type, and duration of stress to balance cell survival and death through an unknown mechanism. Recently, changes in the physical property of Hsf1 condensates due to persistent stress have been suggested to trigger apoptosis, highlighting the importance of biological phase separation and transition in cell fate decisions. In this study, the mechanism underlying Hsf1 droplet formation and oxidative response was investigated through 3D refractive index imaging of the internal architecture, corroborated by molecular dynamics simulations and biophysical/biochemical experiments. We found that, in response to oxidative conditions, Hsf1 formed liquid condensates that suppressed its internal mobility. Furthermore, these conditions triggered the hyper-oligomerization of Hsf1, mediated by disulfide bonds and secondary structure stabilization, leading to the formation of dense core particles in the Hsf1 droplet. Collectively, these data demonstrate how the physical property of Hsf1 condensates undergoes an oxidative transition by sensing redox conditions to potentially drive cell fate decisions. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0969-806X 238 2026 Bone-enhanced high contrast X-ray images derived from attenuation estimation related to ultra-low energy X-rays – An application of an energy-resolving photon-counting detector (ERPCD) 113243 EN Rina Nishigami Graduate School of Medical Sciences, Kanazawa University Natsumi Kimoto Department of Radiological Science, Faculty of Health Sciences, Junshin Gakuen University Takashi Asahara Faculty of Health Sciences, Okayama University Tatsuya Maeda Graduate School of Medical Sciences, Kanazawa University Daiki Kobayashi Graduate School of Medical Sciences, Kanazawa University Sota Goto Faculty of Health Sciences, Kobe Tokiwa University Tomonobu Haba Faculty of Radiological Technology, School of Medical Science, Fujita Health University Yuki Kanazawa Faculty of Life Science, Kumamoto University Shuichiro Yamamoto JOB CORPORATION Hiroaki Hayashi College of Transdisciplinary Sciences for Innovation, Kanazawa University Purpose: X-ray diagnosis in medicine is often used for bone diagnosis based on qualitative observation analysis. However, there are often cases where the contrast of bones is reduced because of the existence of soft-tissues, making it difficult to accurately diagnose the bone conditions. Although the algorithm for bone extraction images was proposed using an energy-resolving photon-counting detector (ERPCD), this algorithm can depict “one” bone material (such as hydroxyapatite under the assumption), and it is difficult to adequately depict other components. The purpose of this study is to develop an algorithm for bone-enhanced high-contrast images that can be virtually represented by the attenuation of extremely low-energy X-rays without making any special assumptions. Methods: High-contrast images were virtually generated based on the attenuation rate of ultra-low energy X-rays. It was determined by fitting the mass attenuation coefficient (μ/ρ) curve to the X-ray attenuation values (μt values) measured at middle (30–40 keV) and high (40–60 keV) energy windows, and extrapolating the μt values to those for the low energy region (E = 5–20 keV). When performing the extrapolation, the effective atomic number (Zeff ) of the object was taken into consideration. The methodology was validated by simulating X-ray projections using a digital human body phantom. The frequency of correspondence between the pixel values in the high-contrast image and the Zeff image was analyzed for each pixel. Results: We succeeded in creating virtual high-contrast X-ray images that reflect the image contrast of monochromatic X-rays of 5–20 keV. It was confirmed that the pixel values in the high-contrast image corresponding to an Zeff = 7.5 (soft-tissue) were completely separated from those corresponding to an Zeff = 9 (bone). The optimization of the energy related to the high contrast images was performed based on the contrast-to-noise ratio (CNR) analysis. The high contrast image with 10 keV showed a good CNR value. Conclusions: Based on the analysis of the attenuation information of middle and high-energy X-rays measured by ERPCDs, we succeeded in creating a novel algorithm that can generate a virtual monochromatic image with high contrast. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0969-806X 239 2026 Counting-loss correction procedure of X-ray imaging detectors with consideration for the effective atomic number of biological objects 113237 EN Natsumi Kimoto Department of Radiological Science, Faculty of Health Sciences, Junshin Gakuen University Rina Nishigami Graduate School of Medical Sciences, Kanazawa University Daiki Kobayashi Graduate School of Medical Sciences, Kanazawa University Tatsuya Maeda Graduate School of Medical Sciences, Kanazawa University Takashi Asahara Department of Radiological Technology, Faculty of Health Sciences, Okayama University Sota Goto Faculty of Health Science, Kobe Tokiwa University Yuki Kanazawa Faculty of Life Science, Kumamoto University Akitoshi Katsumata Oral Radiology and Artificial Intelligence, Asahi University Shuichiro Yamamoto JOB CORPORATION Hiroaki Hayashi College of Transdisciplinary Sciences for Innovation, Kanazawa University It is necessary to correct counting loss caused by the pulse pile-up effect and dead time when using energy-resolving photon-counting detectors (ERPCDs) under “high-counting-rate” conditions in medical and/or industrial settings. We aimed to develop a novel counting-loss correction procedure in which biological objects having effective atomic numbers (Zeff values) of 6.5–13.0 are measured with polychromatic X-rays. To correct for counting loss, such a procedure must theoretically estimate the count value of an ideal X-ray spectrum without counting loss. In this study, we estimated the ideal X-ray spectrum by focusing on the following two points: (1) the X-ray attenuation in an object (Zeff values of 6.5–13.0) and (2) the detector response. Virtual materials having intermediate atomic numbers between 6.5 and 13.0 were generated by using a mixture of polymethylmethacrylate (PMMA, Zeff = 6.5) and aluminum (Al, Zeff = 13.0). We then constructed an algorithm that can perform the counting-loss correction based on the object’s true Zeff value. To demonstrate the applicability of our procedure, we analyzed investigational objects consisting of PMMA and Al using a prototype ERPCD system. A fresh fish sample was also analyzed. The Zeff values agree with the theoretical values within an accuracy of Zeff ±1. In conclusion, we have developed a highly accurate procedure for correcting counting losses for the quantitative X-ray imaging of biological objects. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0171-9335 104 2 2025 Tri-culture model of intestinal epithelial cell, macrophage, and bacteria for the triggering of inflammatory bowel disease on a microfluidic device 151495 EN Shiori Tamura School of Life Science and Technology, Institute of Science Tokyo Clarissa Ellice Talitha Pasang School of Life Science and Technology, Tokyo Institute of Technology Minami Tsuda School of Life Science and Technology, Tokyo Institute of Technology Shilan Ma School of Life Science and Technology, Institute of Science Tokyo Hiromasa Shindo School of Life Science and Technology, Tokyo Institute of Technology Noriyuki Nagaoka Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tomoki Ohkubo Biology-Chemistry Unit, Technology Research Laboratory, Shimadzu Corporation Yoichi Fujiyama Biology-Chemistry Unit, Technology Research Laboratory, Shimadzu Corporation Miho Tamai School of Life Science and Technology, Tokyo Institute of Technology Yoh-ichi Tagawa School of Life Science and Technology, Institute of Science Tokyo Inflammatory bowel disease (IBD) involves gastrointestinal inflammation, due to intestinal epithelial barrier destruction caused by excessive immune activation. Conventional cell culture systems do not provide a model system that can recapitulate the complex interactions between epithelial cells, immune cells, and intestinal bacteria. To address this, we developed a microfluidic device that mimics the inflammatory response associated with microbial invasion of the intestinal mucosa. The device consisted of two media channels, an upper and a lower channel, and a porous membrane between these channels on which C2BBe1 intestinal epithelial cells were seeded to form a tight junction layer. Each electrode was placed in contact with both channels to continuously monitor the tight junction state. Fresh medium flow allowed bacterial numbers to be controlled and bacterial toxins to be removed, allowing co-culture of mammalian cells and bacteria. In addition, RAW264 macrophage cells were attached to the bottom of the lower channel. By introducing E. coli into the lower channel, the RAW264 cells were activated and produced TNF-α, successfully recapitulating a culture model of inflammation in which the C2BBe1cell tight junction layer was destroyed. The main structure of the device was initially made of polydimethylsiloxane to facilitate its widespread use, but with a view to introducing anaerobic bacteria in the future, a similar phenomenon was successfully reproduced using polystyrene. When TPCA-1, an IκB kinase 2 inhibitor was added into this IBD culture model, the tight junction destruction was significantly suppressed. The results suggest that this IBD culture model also is useful as a screening system for anti-IBD drugs. No potential conflict of interest relevant to this article was reported.

American Society for Microbiology Acta Medica Okayama 2379-5042 10 6 2025 Mycobacterium tuberculosis bacillus induces pyroptosis in human lung fibroblasts e00110-25 EN Takemasa Takii Department of Mycobacterium Reference and Research, the Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association Hiroyuki Yamada Department of Mycobacterium Reference and Research, the Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association Chihiro Motozono Department of Molecular Immunology, Research Institute for Microbial Diseases, The University of Osaka Sho Yamasaki Department of Molecular Immunology, Research Institute for Microbial Diseases, The University of Osaka Jordi B. Torrelles Texas Biomedical Research Institute and International Center for the Advancement of Research & Education (I•CARE) Joanne Turner Texas Biomedical Research Institute and International Center for the Advancement of Research & Education (I•CARE) Aoi Kimishima Laboratory of Applied Microbial Chemistry, Ōmura Satoshi Memorial Institute, Kitasato University Yukihiro Asami Laboratory of Applied Microbial Chemistry, Ōmura Satoshi Memorial Institute, Kitasato University Naoya Ohara Department of Oral Microbiology, Graduate School of Medicine, Density and Pharmaceutical Sciences, Okayama University Shigeaki Hida Department of Hygienic Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University Hidetoshi Hayashi Department of Cell Signaling, Graduate School of Pharmaceutical Sciences, Nagoya City University Kikuo Onozaki Department of Hygienic Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University We previously reported that live, but not dead, virulent Mycobacterium tuberculosis (Mtb) H37Rv bacilli induce cell death in human lung fibroblast cell lines, MRC-5, MRC-9, and TIG-1. Here, using two distinct Mtb strains from two different lineages (HN878 lineage 2 and H37Rv lineage 4), we confirmed cell death at day 2 after infection with a device that measures cell growth/cytotoxicity in real time (Maestro-Z [AXION]). Mtb bacilli uptake by the fibroblast was confirmed with a transmission electron microscope on day 2. Expressions of inflammatory cytokines and interleukin (IL)－1β, IL-6, and IL-8 were observed when exposed to live, but not dead bacteria. The cell death of fibroblasts induced by both Mtb strains tested was prevented by caspase-1/4 and NLRP3 inflammasome inhibitors, but not by caspase-3 and caspase-9 inhibitors. Therefore, we classified the fibroblast cell death by Mtb infection as pyroptosis. To investigate the biological and pathological relevance of fibroblast cell death by Mtb infection, we performed dual RNA-Seq analysis on Mtb within fibroblasts and Mtb-infected fibroblasts at day 2. In Mtb bacilli tcrR, secE2, ahpD, and mazF8 genes were highly induced during infection. These genes play roles in survival in a hypoxic environment, production of a calcium-binding protein-inducing cytokine, and regulation of transcription in a toxin-antitoxin system. The gene expressions of IL-1β, IL-6, and IL-8, caspase-4, and NLRP3, but not of caspase-3 and caspase-9, were augmented in Mtb bacilli-infected fibroblasts. Taken together, our study suggests that Mtb bacilli attempt to survive in lung fibroblasts and that pyroptosis of the host fibroblasts activates the immune system against the infection. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0021-8820 77 8 2024 Synthesis and biochemical characterization of naphthoquinone derivatives targeting bacterial histidine kinases 522 532 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 Masayuki Igarashi Institute of Microbial Chemistry (BIKAKEN) Toshihide Okajima SANKEN (The Institute of Scientific and Industrial Research), Osaka University Kohei Mita Graduate School of Education, Okayama University Yuri Yamasaki Graduate School of Education, Okayama University Kaho Sumikura Graduate School of Education, Okayama University Taisei Okumura Graduate School of Education, Okayama University Yuna Tabuchi Graduate School of Education, Okayama University Chigusa Hayashi Institute of Microbial Chemistry (BIKAKEN) Martina Pasqua Istituto Pasteur Italy, Department of Biology and Biotechnology, “C. Darwin”, Sapienza University of Rome Marco Coluccia Istituto Pasteur Italy, Department of Biology and Biotechnology, “C. Darwin”, Sapienza University of Rome Gianni Prosseda Istituto Pasteur Italy, Department of Biology and Biotechnology, “C. Darwin”, Sapienza University of Rome Bianca Colonna Istituto Pasteur Italy, Department of Biology and Biotechnology, “C. Darwin”, Sapienza University of Rome Chie Kohayakawa Department of Lead Exploration Units, Graduate School of Pharmaceutical Sciences, Osaka University Akiyoshi Tani Compound Library Screening Center, Graduate School of Pharmaceutical Sciences, Osaka University Jun-ichi Haruta Department of Lead Exploration Units, Graduate School of Pharmaceutical Sciences, Osaka University Ryutaro Utsumi SANKEN (The Institute of Scientific and Industrial Research), Osaka University Waldiomycin is an inhibitor of histidine kinases (HKs). Although most HK inhibitors target the ATP-binding region, waldiomycin binds to the intracellular dimerization domain (DHp domain) with its naphthoquinone moiety presumed to interact with the conserved H-box region. To further develop inhibitors targeting the H-box, various 2-aminonaphthoquinones with cyclic, aliphatic, or aromatic amino groups and naphtho [2,3-d] isoxazole-4,9-diones were synthesized. These compounds were tested for their inhibitory activity (IC50) against WalK, an essential HK for Bacillus subtilis growth, and their minimum inhibitory concentrations (MIC) against B. subtilis. As a result, 11 novel HK inhibitors were obtained as naphthoquinone derivatives (IC50: 12.6–305 µM, MIC: 0.5–128 µg ml－1). The effect of representative compounds on the expression of WalK/WalR regulated genes in B. subtilis was investigated. Four naphthoquinone derivatives induced the expression of iseA (formerly yoeB), whose expression is negatively regulated by the WalK/WalR system. This suggests that these compounds inhibit WalK in B. subtilis cells, resulting in antibacterial activity. Affinity selection/mass spectrometry analysis was performed to identify whether these naphthoquinone derivatives interact with WalK in a manner similar to waldiomycin. Three compounds were found to competitively inhibit the binding of waldiomycin to WalK, suggesting that they bind to the H-box region conserved in HKs and inhibit HK activity. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2637-6105 7 15 2025 Tailoring Mechanical Properties and Ionic Conductivity of Poly(ionic liquid)-Based Ion Gels by Tuning Anion Compositions 10151 10159 EN Takaichi Watanabe Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Yuna Mizutani Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Carlos G. Lopez Material Science and Engineering Department, The Pennsylvania State University, 80 Pollock Road, State College Tsutomu Ono Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science, and Technology, Okayama University Poly(ionic liquid) (PIL)-based ion gels have emerged as promising materials for advanced electrochemical applications because of their excellent miscibility with ionic liquids (IL), tunable mechanical properties, and high ionic conductivity. Despite extensive studies on PIL-based ion gels, a comprehensive understanding of how different anion combinations in the system affect physicochemical properties is lacking. In this study, we systematically investigate the effect of different anion species, such as bis(trifluoromethanesulfonyl)imide (TFSI) and hexafluorophosphate (PF6), on the mechanical, viscoelastic, and ion conductive behaviors of PIL-based ion gels. We investigate the interplay between anion size, packing density, and polymer segmental dynamics by varying the anion composition in both the PIL network and IL component. Rheological analysis and uniaxial tensile testing results indicate that PF6-containing ion gels exhibit enhanced higher Young’s modulus because of their restricted chain mobility resulting in higher glass transition temperature (Tg). In addition, we confirm the anion exchange between PIL and IL during gel preparation and find that the mechanical and ion conductive properties of the gels are governed by the total molar ratio of anions in the gels. Our findings highlight that tuning the anion composition in PIL-based ion gels provides an effective strategy to tailor their performance, with potential applications for flexible electronics and solid-state electrochemical devices. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 2642-4150 2025 Electrostatically‐Driven Collapse of Polyelectrolytes: The Role of the Solvent's Dielectric Constant EN Anish Gulati Institute of Physical Chemistry, RWTH Aachen University Lingzi Meng Materials Science and Engineering Department, The Pennsylvania State University, State College 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, State College We experimentally confirm a longstanding theoretical prediction of counterion-induced polyelectrolyte collapse in low dielectric media. The scattering behavior of polystyrene sulfonate in different solvents with dielectric permittivities in the range of ε ≃ 12 － 180 is investigated. For high and intermediate ε media, typical polyelectrolyte behavior is observed: the correlation length (ξ) scales with concentration (c) as ξ ∼ c－1∕2, as predicted by various theories. When the dielectric constant of the solvent decreases below ≃ 22, a scaling of ξ ∼ c－1∕3, characteristic of partially collapsed polyelectrolytes, is observed. For these solvents, the correlation peak disappears at high concentrations. Interestingly, polyelectrolyte collapse is observed under both solvophilic and solvophobic conditions, supporting the existence of attractive electrostatic interactions. These results are in qualitative agreement with theoretical predictions which expect chain collapse in low dielectric media due to the influence of condensed counterions, either via dipolar attraction and/or charge-correlation-induced attractions. No potential conflict of interest relevant to this article was reported.

Microbiology Society Acta Medica Okayama 0022-1317 106 7 2025 Summary of taxonomy changes ratified by the International Committee on Taxonomy of Viruses from the Plant Viruses Subcommittee, 2025 002114 EN Luisa Rubino Istituto per la Protezione Sostenibile delle Piante, CNR Peter Abrahamian USDA-ARS, BARC, National Germplasm Resources Laboratory Wenxia An Liaoning Key Laboratory of Urban Integrated Pest Management and Ecological Security, Shenyang University Miguel A. Aranda Centro de Edafología y Biología Aplicada del Segura-CSIC José T. Ascencio-Ibañez Department of Molecular and Structural Biochemistry, North Carolina State University Nicolas Bejerman Unidad de Fitopatología y Modelización Agrícola (UFYMA) INTA-CONICET Arnaud G. Blouin Plant Protection Department Thierry Candresse UMR 1332 Biologie du Fruit et Pathologie, University of Bordeaux, INRAE Tomas Canto Margarita Salas Center for Biological Research (CIB-CSIC) Spanish Council for Scientific Research (CSIC) Mengji Cao National Citrus Engineering and Technology Research Center, Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, Citrus Research Institute, Southwest University John P. Carr Department of Plant Sciences, University of Cambridge Won Kyong Cho Agriculture and Life Sciences Research Institute, Kangwon National University Fiona Constable Agriculture Victoria Research, Department of Energy, Environment and Climate Action and School of Applied Systems Biology, La Trobe University Indranil Dasgupta University of Delhi South Campu Humberto Debat Unidad de Fitopatología y Modelización Agrícola (UFYMA) INTA-CONICET Ralf G. Dietzgen Queensland Alliance for Agriculture and Food Innovation, The University of Queensland Michele Digiaro CIHEAM, Istituto Agronomico Mediterraneo of Bari Livia Donaire Centro de Edafología y Biología Aplicada del Segura-CSIC Toufic Elbeaino CIHEAM, Istituto Agronomico Mediterraneo of Bari Denis Fargette Virus South Data Fiona Filardo Queensland Department of Primary Industries Matthias G. Fischer Max Planck Institute for Marine Microbiology Nuria Fontdevila Plant Protection Department Adrian Fox Fera Science Ltd (Fera), York Biotech Campus Juliana Freitas-Astua Embrapa Cassava and Fruits, Brazilian Agricultural Research Corporation Marc Fuchs Plant Pathology, Cornell University Andrew D.W. Geering Queensland Alliance for Agriculture and Food Innovation, The University of Queensland Mahan Ghafari Department of Biology, University of Oxford Anders Hafrén Swedish University of Agriculture John Hammond USDA-ARS, USNA, Floral and Nursery Plants Research Unit Rosemarie Hammond USDA-ARS, BARC, Molecular Plant Pathology Laboratory Beata Hasiów-Jaroszewska Institute of Plant Protection-NRI Eugenie Hebrard PHIM Plant Health Institute, University of Montpellier, INRAE, CIRAD, IRD, Institute Agro Carmen Hernández Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universitat Politècnica de Valencia-CSIC Jean-Michel Hily Institut Français de la Vigne et du Vin Ahmed Hosseini Vali-e-Asr University of Rafsanjan, Department of Plant Protection Roger Hull Retired from John Innes Centre Alice K. Inoue-Nagata Embrapa Hortaliças Ramon Jordan USDA-ARS, USNA, Floral and Nursery Plants Research Unit Hideki Kondo Institute of Plant Science and Resources, Okayama University Jan F. Kreuze International Potato Center (CIP) Mart Krupovic Institut Pasteur, Université Paris Cité, CNRS UMR6047, Archaeal Virology Unit Kenji Kubota Institute for Plant Protection, NARO Jens H. Kuhn Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health Scott Leisner Department of Biological Sciences, University of Toledo Jean-Michel Lett CIRAD, UMR PVBMT Chengyu Li Liaoning Key Laboratory of Urban Integrated Pest Management and Ecological Security, Shenyang University Fan Li State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University Jun Min Li Institute of Plant Virology, Ningbo University Paola M. López-Lambertini Instituto de Patología Vegetal (IPAVE), INTA, Unidad de Fitopatología y Modelización Agrícola (UFYMA) INTA-CONICET Juan J. Lopez-Moya Centre for Research in Agricultural Genomics, CRAG (CSIC-IRTA-UAB-UB) Francois Maclot UMR 1332 Biologie du Fruit et Pathologie, University of Bordeaux, INRAE Kristiina Mäkinen Department of Agricultural Sciences, University of Helsinki Darren Martin Institute of Infectious Disease and Molecular Medicine, University of Cape Town Sebastien Massart Plant Pathology Laboratory, TERRA Gembloux Agro-Bio Tech, University of Liege W. Allen Miller Department of Plant Pathology, Entomology and Microbiology, Iowa State University Musa Mohammadi Department of Plant Protection, Gorgan University of Agricultural Sciences and Natural Resources Dimitre Mollov USDA-APHIS, Plant Protection and Quarantine Emmanuelle Muller CIRAD, AGAP Institut; AGAP Institut, University of Montpellier; CIRAD, INRAE Tatsuya Nagata Instituto de Ciências Biológicas, Universidade de Brasília Jesús Navas-Castillo Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora” (IHSM-UMA-CSIC), Consejo Superior de Investigaciones Científicas Yutaro Neriya Utsunomiya University Francisco M. Ochoa-Corona Oklahoma State University, Institute for Biosecurity & Microbial Forensics Kazusato Ohshima Saga University Vicente Pallás Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universitat Politècnica de Valencia-CSIC Hanu Pappu Department of Plant Pathology, Washington State University Karel Petrzik Institute of Plant Molecular Biology Mikhail Pooggin PHIM Plant Health Institute, University of Montpellier, INRAE, CIRAD, IRD Maria Isabella Prigigallo Istituto per la Protezione Sostenibile delle Piante, CNR Pedro L. Ramos-González Applied Molecular Biology Laboratory, Instituto Biológico de São Paulo Simone Ribeiro Embrapa Recursos Genéticos e Biotecnologia Katja R. Richert-Pöggeler Julius Kühn Institute, Federal Research Centre for Cultivated Plants, Institute for Epidemiology and Pathogen Diagnostics Philippe Roumagnac CIRAD, UMR PHIM Avijit Roy USDA-ARS, BARC, Molecular Plant Pathology Laboratory, Beltsville, MD, USA Sead Sabanadzovic Department of Agricultural Science and Plant Protection, Mississippi State University Dana Šafářová Department of Cell Biology and Genetics, Faculty of Science, Palacký University Olomouc Pasquale Saldarelli Istituto per la Protezione Sostenibile delle Piante, CNR Hélène Sanfaçon Summerland Research and Development Centre, Agriculture and Agri-Food Canada Cecilia Sarmiento Department of Chemistry and Biotechnology, Tallinn University of Technology Takahide Sasaya Strategic Planning Headquarters, NARO Kay Scheets Department of Plant Pathology, Ecology and Evolution, Oklahoma State University Willem E.W. Schravesande Molecular Plant Pathology, University of Amsterdam Susan Seal Natural Resources Institute, University of Greenwich Yoshifumi Shimomoto Kochi Agricultural Research Center Merike Sõmera Department of Chemistry and Biotechnology, Tallinn University of Technology Livia Stavolone Istituto per la Protezione Sostenibile delle Piante, CNR Lucy R. Stewart Currently unaffiliated Pierre-Yves Teycheney CIRAD, UMR PVBMT & UMR PVBMT, Université de la Réunion John E. Thomas Queensland Alliance for Agriculture and Food Innovation, The University of Queensland Jeremy R. Thompson Plant Health and Environment Laboratory Antonio Tiberini Council for Agricultural Research and Economics, Research Centre for Plant Protection and Certification Yasuhiro Tomitaka Institute for Plant Protection, NARO Ioannis Tzanetakis Department of Entomology and Plant Pathology, Division of Agriculture, University of Arkansas System Marie Umber INRAE, UR ASTRO Cica Urbino PHIM Plant Health Institute, University of Montpellier, INRAE, CIRAD, IRD, Institute Agro Harrold A. van den Burg Molecular Plant Pathology, University of Amsterdam René A.A. Van der Vlugt Wageningen University and Research Arvind Varsani The Biodesign Center for Fundamental and Applied Microbiomics, Center for Evolution and Medicine, School of Life Sciences, Arizona State University Adriaan Verhage Rijk Zwaan Breeding B.V. Dan Villamor Department of Entomology and Plant Pathology, Division of Agriculture, University of Arkansas System Susanne von Bargen Humboldt-Universität zu Berlin, Thaer-Institute of Agricultural and Horticultural Sciences Peter J. Walker The University of Queensland Thierry Wetzel Dienstleistungszentrum Ländlicher Raum Rheinpfalz Anna E. Whitfield North Carolina State University Stephen J. Wylie Food Futures Institute, Murdoch University Caixia Yang Liaoning Key Laboratory of Urban Integrated Pest Management and Ecological Security, Shenyang University F. Murilo Zerbini Dep. de Fitopatologia/BIOAGRO, Universidade Federal de Viçosa Song Zhang National Citrus Engineering and Technology Research Center, Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, Citrus Research Institute, Southwest University In March 2025, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote, newly proposed taxa were added to those under the mandate of the Plant Viruses Subcommittee. In brief, 1 new order, 3 new families, 6 new genera, 2 new subgenera and 206 new species were created. Some taxa were reorganized. Genus Cytorhabdovirus in the family Rhabdoviridae was abolished and its taxa were redistributed into three new genera Alphacytorhabdovirus, Betacytorhabdovirus and Gammacytorhabdovirus. Genus Waikavirus in the family Secoviridae was reorganized into two subgenera (Actinidivirus and Ritunrivirus). One family and four previously unaffiliated genera were moved to the newly established order Tombendovirales. Twelve species not assigned to a genus were abolished. To comply with the ICTV mandate of a binomial format for virus species, eight species were renamed. Demarcation criteria in the absence of biological information were defined in the genus Ilarvirus (family Bromoviridae). This article presents the updated taxonomy put forth by the Plant Viruses Subcommittee and ratified by the ICTV. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 2192-2640 14 10 2024 Biocompatibility of Water-Dispersible Pristine Graphene and Graphene Oxide Using a Close-to-Human Animal Model: A Pilot Study on Swine 2401783 EN Paola Nicolussi Istituto Zooprofilattico Sperimentale della Sardegna Giovannantonio Pilo Istituto Zooprofilattico Sperimentale della Sardegna Maria Giovanna Cancedda Istituto Zooprofilattico Sperimentale della Sardegna Guotao Peng Institute of Environmental Medicine, Karolinska Institutet Ngoc Do Quyen Chau CNRS, Immunology, Immunopathology and Therapeutic Chemistry Alejandro De la Cadena Dipartimento di Fisica, Politecnico di Milano Renzo Vanna Istituto di Fotonica e Nanotecnologie – CNR Yarjan Abdul Samad Cambridge Graphene Centre, University of Cambridge Tanweer Ahmed Cambridge Graphene Centre, University of Cambridge Jeremia Marcellino Cambridge Graphene Centre, University of Cambridge Giuseppe Tedde Istituto Zooprofilattico Sperimentale della Sardegna Linda Giro ImmuneNano Laboratory, Department of Biomedical Sciences Acelya Ylmazer Department of Biomedical Engineering, Ankara University Federica Loi Istituto Zooprofilattico Sperimentale della Sardegna Gavina Carta Istituto Zooprofilattico Sperimentale della Sardegna Loredana Secchi Istituto Zooprofilattico Sperimentale della Sardegna Silvia Dei Giudici Istituto Zooprofilattico Sperimentale della Sardegna Simona Macciocu Istituto Zooprofilattico Sperimentale della Sardegna Dario Polli Dipartimento di Fisica, Politecnico di Milano Yuta Nishina Graduate School of Natural Science and Technology, Okayama University Ciriaco Ligios Istituto Zooprofilattico Sperimentale della Sardegna Giulio Cerullo Dipartimento di Fisica, Politecnico di Milano Andrea Ferrari Cambridge Graphene Centre, University of Cambridge Alberto Bianco CNRS, Immunology, Immunopathology and Therapeutic Chemistry Bengt Fadeel Institute of Environmental Medicine, Karolinska Institutet Giulia Franzoni Istituto Zooprofilattico Sperimentale della Sardegna Lucia Gemma Delogu ImmuneNano Laboratory, Department of Biomedical Sciences Graphene-based materials (GBMs) are of considerable interest for biomedical applications, and the pilot study on the toxicological and immunological impact of pristine graphene (GR) and graphene oxide (GO) using swine as a close-to-human provides valuable insights. First, ex vivo experiments are conducted on swine blood cells, then GBMs are injected intraperitoneally (i.p.) into swine. Hematological and biochemical analyses at various intervals indicate that neither GO nor GR cause systemic inflammation, pro-coagulant responses, or renal or hepatic dysfunction. Importantly, no systemic toxicity is observed. Analysis of a panel of 84 immune-related genes shows minimal impact of GO and GR. The animals are sacrificed 21 days post-injection, and transient absorption imaging and Raman mapping show the presence of GO and GR in the mesentery only. Histological evaluation reveals no signs of alterations in other organs. Thus, clusters of both materials are detected in the mesentery, and GO aggregates are surrounded only by macrophages with the formation of granulomas. In contrast, modest local reactions are observed around the GR clusters. Overall, these results reveal that i.p. injection of GBMs resulted in a modest local tissue reaction without systemic toxicity. This study, performed in swine, provides essential guidance for future biomedical applications of graphene. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2691-3704 2025 Electrochemical Generation of Sulfonamidyl Radicals via Anodic Oxidation of Hydrogen Bonding Complexes: Applications to Electrosynthesis of Benzosultams EN Yasuyuki Okumura Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Eisuke Sato Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Koichi Mitsudo Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Seiji Suga Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Amidyl radicals and sulfonamidyl radicals are widely used in the field of organic synthesis. In particular, the electrochemical oxidation of amides in the presence of bases is one of the most practical methods for generating amidyl radicals. However, it is often difficult to observe the “true” radical precursor, such as an amide anion and/or a hydrogen bonding complex with an amide and a base. We found that a sulfonamide and Bu4NOAc form a 1:1 hydrogen bonding complex by spectroscopic experiments. Cyclic voltammetry suggested that 1:1 hydrogen bonding complexes should be oxidized predominantly under the optimized conditions to afford a sulfonamidyl radical via the proton-coupled electron transfer (PCET) process by the oxidation of the complex. Thus-generated sulfonamidyl radicals could be used in the electrochemical synthesis of a variety of benzosultams. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2470-1343 9 34 2024 Engineering Zeolitic-Imidazolate-Framework-Derived Mo-Doped Cobalt Phosphide for Efficient OER Catalysts 36114 36121 EN Mohammad Atiqur Rahman Department of Chemistry, Graduate School of Science and Technology, Kumamoto University Ze Cai Department of Chemistry, Graduate School of Science and Technology, Kumamoto University Zannatul Mumtarin Moushumy Department of Applied Chemistry and Biochemistry, Graduate School of Science and Technology, Kumamoto University Ryuta Tagawa Department of Chemistry, Graduate School of Science and Technology, Kumamoto University Yoshiharu Hidaka Department of Chemistry, Graduate School of Science and Technology, Kumamoto University Chiyu Nakano Research Core for Interdisciplinary Sciences, Okayama University Md. Saidul Islam Department of Chemistry, Graduate School of Science and Technology, Kumamoto University Yoshihiro Sekine Department of Chemistry, Graduate School of Science and Technology, Kumamoto University Yuta Nishina Research Core for Interdisciplinary Sciences, Okayama University Shintaro Ida Institute of Industrial Nanomaterials (IINa), Kumamoto University Shinya Hayami Institute of Industrial Nanomaterials (IINa), Kumamoto University Designing a cheap, competent, and durable catalyst for the oxygen evolution reaction (OER) is exceedingly necessary for generating oxygen through a water-splitting reaction. In this project, we have designed a ZIF-67-originated molybdenum-doped cobalt phosphide (CoP) using a simplistic dissolution–regrowth method using Na2MoO4 and a subsequent phosphidation process. This leads to the formation of an exceptional hollow nanocage morphology that is useful for enhanced catalytic activity. Metal–organic frameworks, especially ZIF-67, can be used both as a template and as a metal (cobalt) precursor. Molybdenum-doped CoP was fabricated through a two-step synthesis process, and the fabricated Mo-doped CoP showed excellent catalytic activity during the OER with a lower value of overpotential. Furthermore, the effect of the Mo amount on the catalytic activity has been explored. The best catalyst (CoMoP-2) showed an onset potential of around 1.49 V at 10 mA cm–2 to give rise to a Tafel slope of 62.1 mV dec–1. The improved catalytic activity can be attributed to the increased porosity and surface area of the resultant catalyst. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-7345 60 76 2024 Investigating the radical properties of oxidized carbon materials under photo-irradiation: behavior of carbon radicals and their application in catalytic reactions 10544 10547 EN Md Razu Ahmed Research Institute for Interdisciplinary Science, Okayama University Israel Ortiz Anaya Research Institute for Interdisciplinary Science, Okayama University Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Oxidized carbon materials have abundant surface functional groups and customizable properties, making them an excellent platform for generating radicals. Unlike reactive oxygen species such as hydroxide or superoxide radicals that have been reported previously, oxidized carbon also produces stable carbon radicals under photo-irradiation. This has been confirmed through electron spin resonance. Among the various oxidized carbon materials synthesized, graphene oxide shows the largest number of carbon radicals when exposed to blue LED light. The light absorption capacity, high surface area, and unique structural characteristics of oxidized carbon materials offer a unique function for radical-mediated oxidative reactions. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0753-3322 186 2025 (+)-Terrein exerts anti-obesity and anti-diabetic effects by regulating the differentiation and thermogenesis of brown adipocytes in mice fed a high-fat diet 118030 EN Haruka Aoki-Saito Department of Allergy and Respiratory Medicine, Gunma University Graduate School of Medicine Hiroki Mandai Department of Pharmacy, Faculty of Pharmacy, Gifu University of Medical Science Takashi Nakakura Department of Anatomy, Teikyo University School of Medicine Tsutomu Sasaki Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University Tadahiro Kitamura Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University Kazuhiro Omori Department of Pathophysiology-Periodontal Science, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takeshi Hisada Gunma University Graduate School of Health Sciences Shuichi Okada Department of Diabetes, Soleiyu Asahi Clinic Seiji Suga Division of Applied Chemistry, Graduate School of Natural Sciences and Technology, Okayama University Masanobu Yamada Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine Tsugumichi Saito Department of Health & Sports Sciences, Faculty of Education, Tokyo Gakugei University Objective: (+)-Terrein, a low-molecular-weight secondary metabolite from Aspergillus terreus, inhibits adipocyte differentiation in vitro. However, the precise mechanisms underlying the effects of (+)-terrein on adipocytes remain unclear. We hypothesized that (+)-terrein modulates adipogenesis and glucose homeostasis in obesity and diabetes via anti-inflammatory action and regulation of adipocyte differentiation. Hence, in this study, we aimed to investigate the in vivo anti-diabetic and anti-obesity effects of (+)-terrein. Methods: Male C57BL/6 J mice were fed normal chow or high-fat (HF) diet and administered (+)-terrein (180 mg/kg) via intraperitoneal injection. Glucose and insulin tolerance tests, serum biochemical assays, and histological analyses were also performed. Rat brown preadipocytes, mouse brown preadipocytes (T37i cells), and inguinal white adipose tissue (ingWAT) preadipocytes were exposed to (+)-terrein during in vitro adipocyte differentiation. Molecular markers associated with thermogenesis and differentiation were quantified using real-time polymerase chain reaction and western blotting. Results: (+)-Terrein-treated mice exhibited improved insulin sensitivity and reduced serum lipid and glucose levels, irrespective of the diet. Furthermore, (+)-terrein suppressed body weight gain and mitigated fat accumulation by activating brown adipose tissue in HF-fed mice. (+)-Terrein facilitated the in vitro differentiation of rat brown preadipocytes, T37i cells, and ingWAT preadipocytes by upregulating peroxisome proliferator-activated receptor-γ (PPARγ). This effect was synergistic with that of a PPARγ agonist. Conclusion: This study demonstrated that (+)-terrein effectively induces PPARγ expression and brown adipocyte differentiation, leading to reduced weight gain and improved glucose and lipid profiles in HF-fed mice. Thus, (+)-terrein is a potent novel agent with potential anti-obesity and anti-diabetic properties. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1477-0520 2025 From Carboxylic Acids or Their Derivatives to Amines and Ethers: Modern Decarboxylative Approaches for Sustainable C–N and C–O Bond Formation EN Weidan Yan Graduate School of Natural Science and Technology, Okayama University Tian Tian Graduate School of Natural Science and Technology, Okayama University Yasushi Nishihara Research Institute for Interdisciplinary Science (RIIS), Okayama University Amines and ethers represent essential structural motifs in pharmaceuticals, natural products, organic materials, and catalytic systems. The development of novel, environmentally friendly, and cost-effective strategies for constructing C–N and C–O bonds is therefore of significant importance for the synthesis of these compounds. In recent years, carboxylic acids and their derivatives have emerged as attractive, inexpensive, non-toxic, and readily available synthetic building blocks, serving as promising alternatives to aryl halides. Growing evidence has demonstrated that decarboxylative amination and etherification of carboxylic acid derivatives offer a powerful approach for the synthesis of amines and ethers. These transformations proceed via three principal mechanistic pathways, each offering high atom economy. Specifically, carbanions (or organometallic species) generated through heterolytic decarboxylation can react with suitable electrophiles to form C–heteroatom bonds. In contrast, carbon-centred radicals produced through homolytic decarboxylation can couple with heteroatom-based reagents via radical recombination or oxidative trapping. Additionally, carbocations are typically formed via electrochemical oxidation of carboxylic acids: oxidative decarboxylation first yields a carbon radical, which is then further oxidized at the anode to generate a carbocation. This highly electrophilic intermediate can subsequently be intercepted by heteroatom nucleophiles to construct C–N or C–O bonds. This review highlights recent advances in the field, with a focus on transition metal catalysis, photoredox catalysis, and electrochemical methods for decarboxylative amination and etherification. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1861-4728 2025 Alkoxy‐Substituted Anthrabis(Thiadiazole)‐Terthiophene Copolymers for Organic Photovoltaics: A Unique Wavy Backbone Enhances Aggregation, Molecular Order, and Device Efficiency e00678 EN Yi Yan Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hiroki Mori Research Institute for Interdisciplinary Science, Okayama University Tomoki Yoshino Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Ryuki Inami Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Jiaxin Chang Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Junqing Gao Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yasushi Nishihara Research Institute for Interdisciplinary Science, Okayama University Two polymer donors, PATz3T-o6BO and PATz3T-o6HD, incorporating alkoxy-substituted anthra[1,2-c:5,6-c′]bis([1,2,5]thiadiazole), were strategically designed and synthesized. The unique wavy backbone of these polymers effectively reduced aggregation, leading to enhanced solubility and significantly improved molecular ordering. Consequently, the PATz3T-o6HD:Y12-based solar cells achieved a power conversion efficiency (PCE) of 7.94%. These findings provide valuable insights into the molecular design of high-performance polymer donors for organic photovoltaics (OPVs). No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2050-7488 13 23 2025 A meta-linked isomer of ITIC: influence of aggregation patterns on open-circuit voltage in organic solar cells 17720 EN Kai Wang The Institute of Scientific and Industrial Research (SANKEN), The University of Osaka Seihou Jinnai The Institute of Scientific and Industrial Research (SANKEN), The University of Osaka Kaito Uesaka Graduate School of Natural Science & Technology, Okayama University Akira Yamakata Graduate School of Natural Science & Technology, Okayama University Yutaka Ie The Institute of Scientific and Industrial Research (SANKEN), The University of Osaka Improving the open-circuit voltage (VOC) of organic solar cells (OSCs) remains an important challenge. While it is known that the energy levels at the donor/acceptor (D/A) interface affect the VOC, the impact of aggregation patterns on the energy levels at the D/A interface has not been fully elucidated. Herein, we focus on ITIC, a widely used acceptor in OSCs, and designed a meta-linked isomer of ITIC (referred to as im-ITIC) to alter molecular symmetry and modify substitution arrangements. Concentration-dependent 1H NMR spectra revealed that im-ITIC shows stronger aggregation behavior in solution. Single-crystal X-ray analysis showed that im-ITIC forms both tail-to-tail (J-aggregation) and face-to-face (H-aggregation) stacking modes, whereas ITIC exclusively forms tail-to-tail stacking. OSCs based on PBDB-T:im-ITIC showed a high VOC value of 1.02 V, which is 0.12 V higher than that of those based on PBDB-T:ITIC. Time-resolved infrared measurements revealed the lifetime of free electrons for the pristine and blend films. The energy levels of the charge transfer state (ECT) for PBDB-T:im-ITIC- and PBDB-T:ITIC OSCs were determined to be 1.57 and 1.39 eV, respectively, correlating with the VOC values. Theoretical calculations indicated that pronounced H-aggregation in im-ITIC increases the ECT compared with J-aggregation, contributing to the improved VOC. This study underscores the critical impact of molecular aggregation patterns on energy alignment and VOC enhancement, offering insights into molecular design for achieving high VOC in OSCs. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0014-5793 599 13 2025 Characterization of molecular mechanisms of CaMKKα/1 oligomerization 1914 1924 EN Shun Uenoyama Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Hayato Nitta Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Okayama University Satomi Ohtsuka Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Masaki Magari Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Futoshi Suizu Department of Medical Technology, Kagawa Prefectural University of Health Sciences Hiroshi Tokumitsu Calcium/calmodulin-dependent protein kinase kinase (CaMKK) is an activating kinase for calcium/calmodulin-dependent protein kinase type 1 (CaMKI), calcium/calmodulin-dependent protein kinase type IV (CaMKIV), RAC-alpha serine/threonine-protein kinase (PKB), and AMP-activated protein kinase (AMPK) that has been reported to form an active oligomer in cells. Glutathione S-transferase (GST) pulldown assay from the extracts of COS-7 cells expressing GST- and His6-CaMKKα/1 mutants showed that the C-terminal region containing the autoinhibitory and calmodulin (CaM)-binding sequence (residues 438–463) is required for CaMKKα/1 homo-oligomerization. This was confirmed by the fact that the GST-CaMKKα/1 C-terminal domain (residues 435–505) directly interacted with EGFP-CaMKKα/1 residues 435–505 as well as with wild-type CaMKKα/1. Notably, once oligomerized in cells, CaMKKα/1 is neither exchangeable between the oligomeric complexes nor dissociated by Ca2+/CaM binding. These results support stable oligomerization of CaMKK in the cells by intermolecular self-association of its C-terminal region containing a regulatory domain. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2041-6520 16 26 2025 Collective motions in the primary coordination sphere: a critical functional framework for catalytic activity of the oxygen-evolving complex of photosystem II 12024 EN Hiroshi Isobe Takayoshi Suzuki Research Institute for Interdisciplinary Science, Okayama University Michihiro Suga Research Institute for Interdisciplinary Science, Okayama University Jian-Ren Shen Research Institute for Interdisciplinary Science, Okayama University Kizashi Yamaguchi Center for Quantum Information and Quantum Biology, Osaka University Photosynthetic water oxidation, vital for dioxygen production and light energy conversion, is catalyzed by the oxygen-evolving complex of photosystem II, where the inorganic Mn4CaO5 cluster acts as the catalytic core. In this study, we investigate the functional significance of collective motions of amino acid side chains within the primary coordination sphere of the Mn cluster, focusing on their role in modulating the energetic demands for catalytic transformations in the S3 state. We applied regularized canonical correlation analysis to quantitatively correlate the three-dimensional arrangement of coordinating atoms with catalytic driving forces computed via density functional theory. Our analysis reveals that distinct collective side chain motions profoundly influence the energetic requirements for structural reconfigurations of the Mn cluster, achieved through expansion and contraction of the ligand cavity while fine-tuning its geometry to stabilize key intermediates. Complementary predictions from a neural network-based machine learning model indicate that the coordination sphere exerts a variable energetic impact on the catalytic transformations of the Mn cluster, depending on the S-state environment. Integrated computational analyses suggest that the extended lifetime of the S3YZ˙ state, consistently observed after three flash illuminations, may result from slow, progressive protein dynamics that continuously reshape the energy landscape, thereby shifting the equilibrium positions of rapid, reversible chemical processes over time. Overall, our findings demonstrate that collective motions in the primary coordination sphere constitute an active, dynamic framework essential for the efficient execution of multi-electron catalysis under ambient conditions, while simultaneously achieving a high selectivity with irreversible nature required for effective 3O2 evolution. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0039-9140 297 2026 Microfluidic paper-based analytical devices for antioxidant vitamins C and E in foods 128540 EN Mana Kawahara Department of Chemistry, Okayama University Kaewta Danchana Department of Chemistry, Okayama University Takashi Kaneta Department of Chemistry, Okayama University In this study, we developed microfluidic paper-based analytical devices (μPADs) for the determination of antioxidant vitamins. The proposed μPADs utilize the reduction of metal ions by hydrophilic and hydrophobic antioxidant vitamins, which is followed by colorimetric reactions with chelating reagents. Hydrophilic vitamin C reduces Fe(III) to Fe(II) and forms a stable Fe(II)-bathophenanthroline complex in an aqueous solution. By contrast, this complex is unstable in organic solvents, and hydrophobic vitamin E requires Fe(III) and bathophenanthroline to be replaced with Cu(II) and bathocuproine. In these results, the relationship between the logarithm of a vitamin's concentration and its color intensity was linear and ranged from 4.4 to 35 mg L－1 for ascorbic acid and 50–200 mg L－1 for α-tocopherol. The limits of detection, estimated from the standard deviation of blank samples, were 3.1 mg L－1 for ascorbic acid and either 27 mg L－1 (in hexane) or 48 mg L－1 (in ethanol) for α-tocopherol. The proposed method was used to quantify vitamin C in bell peppers, mandarin oranges, kiwifruit, and lemons, as well as vitamin E in almonds, almond milk, and dietary supplements. The results demonstrate the effectiveness of these μPADs for the practical analysis of antioxidant vitamins in food samples. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0910-6340 2025 Innovations in paper-based analytical devices and portable absorption photometers for onsite analysis EN Sasikarn Seetasang Department of Chemistry, Faculty of Science and Technology, Thammasat University Mika I. Umeda Department of Chemistry, Okayama University Jianchao Ren Department of Chemistry, Okayama University Takashi Kaneta Department of Chemistry, Okayama University Two types of analytical instruments and devices―one sophisticated high-performance instrument and another portable device―have been the focus of recent trends in analytical science. The necessity of point-of-care testing and onsite analysis has accelerated the advancement of high-performance, user-friendly portable analytical devices such as paper-based analytical devices (PADs) and light-emitting diode-based portable photometers. In this review, we summarize our achievements in the study of PADs and portable photometers. Several types of PADs are capable of performing titrations, metal ion analysis, and food analysis, while photometers, which consist of paired emitter–detector light-emitting diode (PEDD) photometers, are used for thiocyanate and herbicide analysis. These PADs and photometers permit the onsite determination of real environmental, body fluid, and food samples when an equipped laboratory is unavailable. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2772-4174 13 2025 Photochemical internalization of mRNA using a photosensitizer and nucleic acid carriers 100242 EN Hayaki Maemoto Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Ryohei Suzaki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kazunori Watanabe Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University Keiji Itaka Department of Biofunction Research, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University Takashi Ohtsuki Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University mRNA has great potential for therapeutic applications because it can encode a variety of proteins and antigens, in addition to advantages over DNA in terms of gene expression without genomic integration, nuclear localization, or transcription. However, therapeutic applications of mRNA require safe and effective delivery into target cells. Therefore, we aimed to investigate photochemical internalization (PCI) as a promising strategy for delivering mRNA to target cells. In this strategy, mRNA is taken up into cells by endocytosis, accumulates in endosomes, and is released in a light-dependent manner from the endosomes using an endosome-accumulating photosensitizer, aluminum phthalocyanine disulfonate (AlPcS2a), in combination with nucleic acid carrier molecules. We compared the efficacy of various nucleic acid carriers, including branched polyethyleneimine (bPEI) and poly{N'-[N-(2-aminoethyl)-2-aminoethyl] aspartamide} (PAsp(DET)) under the same conditions for PCI-based mRNA delivery. Our results indicated that bPEI and PAsp(DET) at low N/P ratios exhibited efficient light-enhancement of mRNA expression by PCI with AlPcS2a. Notably, bPEI exhibited the highest light-dependent mRNA delivery among the carriers evaluated (including cationic polymers, cationic peptides, and lipids), whereas PAsp(DET) showed promise for clinical use because of its lower toxicity compared with bPEI. This PCI strategy allows effective cytosolic mRNA delivery at low N/P ratios, thereby reducing cationic carrier molecule-induced cytotoxicity. This method allows spatiotemporal control of protein expression and holds potential for novel light-dependent mRNA therapies. Overall, this study provided valuable insights into optimizing mRNA delivery systems for therapeutic applications. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1477-0520 23 2025 One-pot synthesis of trans-2,3-diaminoindolines through 2,3-diamination of electrophilic indolines 6699 6703 EN Yuito Kobori Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Keisuke Tokushige Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takumi Abe Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Despite recent advances in the synthesis of 2,3-diaminoindole derivatives, construction of 2,3-diaminoindolines, whose two amine moieties on each molecule differ from one another has yet to be achieved. In this work, we developed a concise one-pot protocol for differentiated diamination involving reacting a C2,C3-electrophilic indole reagent with amines to access a variety of previously inaccessible 2,3-diaminoindolines. Furthermore, the synthetic utility of this protocol was demonstrated by a successful gram-scale reaction and further transformation of the 2,3-diaminoindolines. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0743-7463 41 21 2025 Unraveling the Molecular Mechanism of Transient Multilamellar Formation in Ethanol-Modified Vesicle Solutions 13372 13380 EN Kana Shibata Department of Materials Chemistry, Nagoya University Masatoshi Maeki Division of Applied Chemistry, Faculty of Engineering, Hokkaido University Manabu Tokeshi Division of Applied Chemistry, Faculty of Engineering, Hokkaido University Wataru Shinoda Research Institute for Interdisciplinary Science, Okayama University A recent microfluidic-based small-angle X-ray scattering (SAXS) measurement intriguingly suggested the transient formation of multilamellar structures during the mixing of unilamellar vesicles with ethanol in an aqueous solution. This study explores a possible molecular mechanism underlying this phenomenon, primarily through coarse-grained molecular dynamics (CG-MD) simulations. We first examined lipid aggregate morphology as a function of ethanol concentration in an aqueous solution. Even though vesicles were observed in pure aqueous solution, increasing ethanol concentrations led to more frequent pore formation in vesicular membranes. At ethanol concentrations above 52%, vesicles destabilized and transformed into worm-like micelles. We hypothesized that the transient multilamellar structures might arise from vesicle stacking due to variations in the effective interactions between vesicles. However, a series of potential of mean force (PMF) calculations consistently showed repulsive interactions between vesicles, regardless of ethanol concentration, ruling out this possibility. In contrast, once lipid aggregates transformed into worm-like micelles, the PMF barrier between them dropped (∼5kBT), promoting fusion. Our CG-MD simulations further demonstrated that lipid aggregates (micelles) readily fused and grew in high ethanol concentrations. Upon subsequent exposure to lower ethanol levels, these enlarged aggregates reorganized into vesicles with internal lamellar structure─multilamellar vesicles. These findings suggest that the heterogeneous mixing of unilamellar vesicular solutions with ethanol in a microfluidic device plays a key role in the emergence of transient multilamellar structures. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0021-9258 301 7 2025 A repertoire of visible light–sensitive opsins in the deep-sea hydrothermal vent shrimp Rimicaris hybisae 110291 EN Yuya Nagata Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Norio Miyamoto Institute for Extra-Cutting-Edge Science and Technology Avant-Garde Research (X-Star), Japan Agency for Marine-Earth Science and Technology (JAMSTEC) Keita Sato Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yosuke Nishimura Research Center for Bioscience and Nanoscience (CeBN), Research Institute for Marine Resources Utilization, Japan Agency for Marine-Earth Science and Technology (JAMSTEC) Yuki Tanioka School of Pharmaceutical Sciences, Okayama University Yuji Yamanaka School of Pharmaceutical Sciences, Okayama University Susumu Yoshizawa Atmosphere and Ocean Research Institute, The University of Tokyo Kuto Takahashi Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kohei Obayashi Department of Biology, Graduate School of Science, Kobe University Hisao Tsukamoto Department of Biology, Graduate School of Science, Kobe University Ken Takai Institute for Extra-Cutting-Edge Science and Technology Avant-Garde Research (X-Star), Japan Agency for Marine-Earth Science and Technology (JAMSTEC) Hideyo Ohuchi Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takahiro Yamashita Department of Biophysics, Graduate School of Science, Kyoto University Yuki Sudo Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Keiichi Kojima Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Unlike terrestrial environments, where humans reside, there is no sunlight in the deep sea. Instead, dim visible light from black-body radiation and bioluminescence illuminates hydrothermal vent areas in the deep sea. A deep-sea hydrothermal vent shrimp, Rimicaris hybisae, is thought to detect this dim light using its enlarged dorsal eye; however, the molecular basis of its photoreception remains unexplored. Here, we characterized the molecular properties of opsins, universal photoreceptive proteins in animals, found in R. hybisae. Transcriptomic analysis identified six opsins: three Gq-coupled opsins, one Opn3, one Opn5, and one peropsin. Functional analysis revealed that five of these opsins exhibited light-dependent G protein activity, whereas peropsin exhibited the ability to convert all-trans-retinal to 11-cis-retinal like photoisomerases. Notably, all the R. hybisae opsins, including Opn5, convergently show visible light sensitivity (around 457–517 nm), whereas most opsins categorized as Opn5 have been demonstrated to be UV sensitive. Mutational analysis revealed that the unique visible light sensitivity of R. hybisae Opn5 is achieved through the stabilization of a protonated Schiff base by a counterion residue at position 83 (Asp83), which differs from the position identified in other opsins. These findings suggest that the vent shrimp R. hybisae has adapted its photoreceptive devices to dim deep-sea hydrothermal light by selectively maintaining a repertoire of visible light–sensitive opsins, including the uniquely tuned Opn5. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1523-7060 27 26 2025 Transformation of α,β-Unsaturated Aldehydes with a Small Amount of Electricity: Cyanosilylation, Isomerization, and Nucleophilic Addition 6953 6958 EN Mayu Fujii Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nanaho Ueno Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Koichi Mitsudo Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Eisuke Sato Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Seiji Suga Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University An electrochemical method was developed to convert α,β-unsaturated aldehydes into carboxylic acid derivatives via cyanosilylation, isomerization, and nucleophilic addition. This reaction is more sustainable than the usual electrochemical organic reaction because this reaction proceeds catalytically with active species generated by a very small amount of electricity. Furthermore, scale-up synthesis with a flow reactor has been achieved. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0039-9140 295 2025 Using a microfluidic paper-based analytical device and solid-phase extraction to determine phosphate concentration 128303 EN Kaewta Danchana Department of Chemistry, Okayama University Haruka Namba Department of Chemistry, Okayama University Takashi Kaneta Department of Chemistry, Okayama University Phosphate is an essential nutrient, but in high concentrations it contributes to water pollution. Traditional methods for phosphate measurement, such as absorption spectrophotometry and ion chromatography, require expensive equipment and skilled operators. This study introduces a microfluidic paper-based analytical device (μPAD) that is designed to accomplish field-based, low-concentration phosphate measurements. This μPAD utilizes colorimetric detection based on the molybdenum blue method. Herein, we describe how the conditions were optimized in terms of design and sensitivity by adjusting reagent concentrations, paper thickness, and the time frames for sample introduction, and reaction. The operation consists of simply dipping the μPAD into a sample, capturing images in a home-made photo studio box, and processing the images with ImageJ software to measure RGB intensity. An additional preconcentration step involves solid-phase extraction with an anion exchange resin that achieves a 10-fold enrichment, which enables detection that ranges from 0.05 to 1 mg L－1 with a detection limit of 0.089 mg L－1 and a quantification limit of 0.269 mg L－1. The replicated measurements showed good reproducibility both intraday and interday (five different days) as 4.7 % and 3.0 % of relative standard deviations, respectively. After storage in a refrigerator for as long as 26 days, this μPAD delivered stable and accurate results for real-world samples of natural water, soil, and toothpaste. The results produced using this system correlate well with those produced via spectrophotometry. This μPAD-based method is a cost-effective, portable, rapid, and simple approach that allows relatively unskilled operators to monitor phosphate concentrations in field applications. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 2193-5807 14 7 2025 2-Hydroxy-3-(Pyrrolidin-1-yl)-Indolines: A Platform for Accessing Decorated Deaminokynurenines Enabled by a Double Tautomeric Control e202500439 EN Keisuke Tokushige Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takumi Abe Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University In this study we introduce indoline hemiaminals as phenacyl bromide surrogates for the synthesis of deaminokynurenine derivatives through cyclic-linear tautomeric intermediates. The reaction proceeds through a tandem process involving the ring opening of indoline hemiaminals, generating transient acyclic aldehydes which are then trapped with in situ generated enolate species. Our protocol overcomes traditional dilemma in production of polar-mismatch 1,4-dicarbonyl compounds by utilizing a transient highly electrophilic linear aldehyde and late-stage transposition of carbonyl moiety. The synthetic utility of our transformation was demonstrated by follow-up transformations, including the first total synthesis of quinoline-2,4-dione alkaloid. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1523-7060 27 18 2025 Electrochemical Oxidation of Benzyl Alcohols via Hydrogen Atom Transfer Mediated by 2,2,2-Trifluoroethanol 4737 4741 EN Takahiro Kawajiri API R&D Laboratory, Research Division, Shionogi & Co., Ltd. Masahiro Hosoya API R&D Laboratory, Research Division, Shionogi & Co., Ltd. Satoshi Goda API R&D Laboratory, Research Division, Shionogi & Co., Ltd. Eisuke Sato Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Seiji Suga Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University We report a novel electrochemical oxidation of benzyl alcohols. We found that trifluoroethanol plays a role as a hydrogen atom transfer (HAT) mediator, enabling the oxidation of electron-deficient substrates that are difficult to directly oxidize on electrode surfaces. Density functional theory calculations, cyclic voltammetry measurements, and constant potential electrolysis studies supported the proposed HAT mechanism. Moreover, the obtained carbonyl compounds could be functionalized in an electrochemical one-pot manner, further highlighting their synthetic utility. No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 2470-1343 2025 High-Resolution HPLC for Separating Peptide-Oligonucleotide Conjugates EN Miyako Naganuma Division of Organic Chemistry, National Institute of Health Sciences Genichiro Tsuji Division of Organic Chemistry, National Institute of Health Sciences Misato Amiya YMC CO., LTD. Reira Hirai YMC CO., LTD. Yuki Higuchi YMC CO., LTD. Naoko Hata YMC CO., LTD. Saoko Nozawa YMC CO., LTD. Daishi Watanabe Division of Organic Chemistry, National Institute of Health Sciences Taeko Nakajima YMC CO., LTD. Yosuke Demizu Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Division of Pharmaceutical Science, Okayama University Peptide-oligonucleotide conjugates (POCs) are chimeric molecules that combine the specificity of oligonucleotides with the functionality of peptides, improving the delivery and therapeutic potential of nucleic acid-based drugs. However, the analysis of POCs, particularly those containing arginine-rich sequences, poses major challenges because of aggregation caused by electrostatic interactions. In this study, we developed an optimized high-performance liquid chromatography (HPLC) method for analyzing POCs. Using a conjugate of DNA and nona-arginine as a model compound, we systematically investigated the effects of various analytical parameters, including column type, column temperature, mobile-phase composition, and pH. A column packed with C18 resin with wide pores combined with butylammonium acetate as the ion-pairing reagent and an optimal column temperature of 80 degrees C provided superior peak resolution and sensitivity. The optimized conditions gave clear separation of POCs from unlinked oligonucleotides and enabled the detection of nucleic acid fragments lacking an alkyne moiety as a linkage part, which is critical for quality control. Our HPLC method is robust and reproducible and substantially reduces the complexity, time, and cost associated with the POC analysis. The method may improve the efficiency of quality control in the production of POCs, thereby supporting their development as promising therapeutic agents for clinical applications. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2624-8549 7 2 2025 Molecular Iodine-Catalyzed Synthesis of 3,3-Disubstituted Isatins: Total Synthesis of Indole Alkaloid, 3,3-Dimethoxy-2-oxindole 43 EN Keisuke Tokushige Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shota Asai School of Pharmacy, Shujitsu University Takumi Abe Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University 3,3-Dialkoxy-2-oxindoles are prevalent in natural products and exhibit unique biological activities. Among them, acyclic alkoxy analogues show instability in acidic conditions, making access to acyclic isatin ketals highly challenging. Conventional methods for the synthesis of 3,3-dialkoxy-2-oxindoles usually require strongly acidic and harsh reaction conditions, resulting in a low overall efficiency. Herein, we report on an acid- and metal-free protocol for the synthesis of 3,3-dialkoxy-2-oxindoles from isatins through an iodine-catalyzed ketalization. This photochemical protocol does not require the use of any specific reagents such as metal catalysts. Furthermore, the total synthesis of an unprecedented 2-oxindole alkaloid bearing 3,3-dimethoxy moiety is achieved. No potential conflict of interest relevant to this article was reported.

Informa UK Limited Acta Medica Okayama 0737-3937 43 6 2025 Spray-drying of polymer solutions across a broad concentration range and the subsequent formation of a few micro- ∼nano-meter sized fibers 1108 1116 EN Chika Araga Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University Kaito Fukushima Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University Haruna Sato Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University Nao Honda Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University Takato Hasegawa Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University Koichi Nakaso Division of Chemistry and Biochemistry, Graduate School of 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 Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University Spray drying is a widely utilized technique for the concentration and fine particulation of dried products. This study demonstrated that a versatile spray dryer, equipped with a two-fluid nozzle atomizer, can convert polymer solutions into nanoscale fibers by manipulating the conditions of the polymer solutions. The polymers employed in this research included polyvinylpyrrolidones (Mw 24.5 k to 60 kDa), dextrans (70 k to 450–650 kDa), pullulan, gum Arabic, Eudragit and agar, with methanol and water serving as solvents. Various combinations of polymers and solvents were subjected to spray drying at polymer concentrations ranging from 5 to 1000 g/L. Scanning electron microscopy analyses of the spray-dried samples indicated that the products transitioned from micrometer-sized particles to sub-micrometer fibers in several instances when the polymer concentrations exceeded specific threshold levels. The investigation also explored the relationship between these threshold concentrations and the surface tension and viscosity of the polymer solutions. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 1083-351X 301 4 2025 Roles of basic amino acid residues in substrate binding and transport of the light-driven anion pump Synechocystis halorhodopsin (SyHR) 108334 EN Masaki Nakama Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tomoyasu Noji Department of Applied Chemistry, The University of Tokyo Keiichi Kojima Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Susumu Yoshizawa Atmosphere and Ocean Research Institute, The University of Tokyo Hiroshi Ishikita Department of Applied Chemistry, The University of Tokyo Yuki Sudo Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Microbial rhodopsins are photoreceptive seventransmembrane a-helical proteins, many of which function as ion transporters, primarily for small monovalent ions such as Na+, K+, Cl-, Br-, and I-. Synechocystis halorhodopsin (SyHR), identified from the cyanobacterium Synechocystis sp. PCC 7509, uniquely transports the polyatomic divalent SO42- inward, in addition to monovalent anions (Cl- and Br-). In this study, we conducted alanine-scanning mutagenesis on twelve basic amino acid residues to investigate the anion transport mechanism of SyHR. We quantitatively evaluated the Cl-and SO42- transport activities of the WT SyHR and its mutants. The results showed a strong correlation between the Cl-and SO42- transport activities among them (R = 0.94), suggesting a shared pathway for both anions. Notably, the R71A mutation selectively abolished SO42- transport activity while maintaining Cl- transport, whereas the H167A mutation significantly impaired both Cl-and SO42- transport. Furthermore, spectroscopic analysis revealed that the R71A mutant lost its ability to bind SO42- due to the absence of a positive charge, while the H167A mutant failed to accumulate the O intermediate during the photoreaction cycle (photocycle) due to reduced hydrophilicity. Additionally, computational analysis revealed the SO42- binding modes and clarified the roles of residues involved in its binding around the retinal chromophore. Based on these findings and previous structural information, we propose that the positive charge and hydrophilicity of Arg71 and His167 are crucial for the formation of the characteristic initial and transient anion-binding site of SyHR, enabling its unique ability to bind and transport both Cl-and SO42-. No potential conflict of interest relevant to this article was reported.

Beilstein-Institut Acta Medica Okayama 1860-5397 21 2025 Photochemically assisted synthesis of phenacenes fluorinated at the terminal benzene rings and their electronic spectra 670 679 EN Yuuki Ishii Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Minoru Yamaji Division of Molecular Science, Graduate School of Science and Engineering, Gunma University Fumito Tani Institute for Materials Chemistry and Engineering, Kyushu University Kenta Goto Institute for Materials Chemistry and Engineering, Kyushu University Yoshihiro Kubozono Research Institute for Interdisciplinary Science, Okayama University Hideki Okamoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University [n]Phenacenes ([n] = 5-7), octafluorinated at the terminal benzene rings (F8-phenacenes: F8PIC, F8FUL, and F87PHEN), were photochemically synthesized, and their electronic spectra were investigated to reveal the effects of the fluorination on the electronic features of phenacene molecules. F8-Phenacenes were conveniently synthesized by the Mallory photoreaction of the corresponding fluorinated diarylethenes as the key step. Upon fluorination on the phenacene cores, the absorption and fluorescence bands of the F8-phenacenes in CHCl3 systematically red-shifted by ca. 3-5 nm compared to those of the corresponding parent phenacenes. The vibrational progressions of the absorption and fluorescence bands were little affected by the fluorination in the solution phase. In the solid state, the absorption band of F8-phenacenes appeared in the similar wavelength region for the corresponding parent phenacenes whereas their fluorescence bands markedly red-shifted and broadened. These observations suggest that the intermolecular interactions of excited-state F8-phenacene molecules are significantly different from those of the corresponding parent molecules, most likely due to different crystalline packing motifs. No potential conflict of interest relevant to this article was reported.

Frontiers Media Acta Medica Okayama 1662-5102 19 2025 Acetoacetate, a ketone body, attenuates neuronal bursts in acutely-induced epileptiform slices of the mouse hippocampus 1551700 EN Hao Wen Department of Biophysical Chemistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Nagisa Sada Department of Biophysical Chemistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tsuyoshi Inoue Department of Biophysical Chemistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University The ketogenic diet increases ketone bodies (beta-hydroxybutyrate and acetoacetate) in the brain, and ameliorates epileptic seizures in vivo. However, ketone bodies exert weak or no effects on electrical activity in rodent hippocampal slices. Especially, it remains unclear what kinds of conditions are required to strengthen the actions of ketone bodies in hippocampal slices. In the present study, we examined the effects of acetoacetate on hippocampal pyramidal cells in normal slices and epileptiform slices of mice. By using patch-clamp recordings from CA1 pyramidal cells, we first confirmed that acetoacetate did not change the membrane potentials and intrinsic properties of pyramidal cells in normal slices. However, we found that acetoacetate weakened spontaneous epileptiform bursts in pyramidal cells of epileptiform slices, which were acutely induced by applying convulsants to normal slices. Interestingly, acetoacetate did not change the frequency of the epileptiform bursts, but attenuated individual epileptiform bursts. We finally examined the effects of acetoacetate on excitatory synaptic barrages during epileptiform activity, and found that acetoacetate weakened epileptiform bursts by reducing synchronous synaptic inputs. These results show that acetoacetate attenuated neuronal bursts in epileptiform slices, but did not affect neuronal activity in normal slices, which leads to seizure-selective actions of ketone bodies. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0026-265X 210 2025 A microfluidic paper-based analytical device that uses gelatin film to assay protease activity via time readout 112952 EN Jianchao Ren Department of Chemistry, Okayama University Kaewta Danchana Department of Chemistry, Okayama University Takashi Kaneta Department of Chemistry, Okayama University Food processing, detergents, and pharmaceuticals frequently employ proteases, which are enzymes that break the chemical bonds of both proteins and peptides. In this work, we developed a microfluidic paper-based analytical device (µPAD) for protease activity assays via time readout. To accomplish this, we folded the µPAD to form layers, then inserted a water-insoluble gelatin film between the layers of paper to form the device. Lamination helps to maintain the gelatin film between the introduction zone, which is the upper layer, and the detection channel, which is the lower layer. Proteases decompose the gelatin film when it enters the introduction zone, which then allows it to flow into the detection channel. The protease activity in the sample solution determines the time required to dissolve the gelatin film, which leads to a linear relationship between the logarithm of the protease concentration and the time required to flow the solution a specific distance on the detection channel. The µPAD was used to measure proteases in concentrations that ranged from 0.25 to 1 mg L－1 for bromelain, 2.5 to 10 mg L－1 for papain, and 1 to 8 mg L－1 for trypsin. The limits of quantification for bromelain, papain, and trypsin were 0.41, 2.7, and 9.2 mg mL－1, respectively. The relative standard deviations for bromelain were smaller than 2 % for concentrations ranging from 0.5 to 1.0 mg L－1. We compared the µPAD to a commercially available protease activity assay kit, which relies on quenching fluorescein isothiocyanate-labeled casein. Both methods demonstrated the same order of activity: bromelain > papain > trypsin. The proposed device allowed the assay of bromelain in both pineapple pulp and juice, which were stored at room temperature. When first using the proposed device, the bromelain in the pulp gradually lost its activity, while the activity of the bromelain in the juice showed no significant change for five days. The µPAD requires no analytical instruments for quality control and monitoring of the protease activity in food. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-7345 61 25 2025 Recent development of azahelicenes showing circularly polarized luminescence 4757 4773 EN Chihiro Maeda Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Tadashi Ema Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Recently, a variety of circularly polarized luminescence (CPL) dyes have been developed as next-generation chiroptical materials. Helicenes, ortho-fused aromatics, have been recognized as some of the most promising CPL dyes. Although typical carbohelicenes show CPL, weak fluorescence is often emitted in the blue region. In contrast, heteroatom-embedded helicenes (heterohelicenes) can show intense fluorescence and CPL in the visible region because heteroatoms alter the electronic states of helicene frameworks. Among various heterohelicenes, nitrogen-embedded helicenes (azahelicenes) have unique features such as facile functionalization and sensitive responses to acid/base or metal ions. Furthermore, polycyclic aromatic hydrocarbons (PAHs) containing azaborine units have been recognized as excellent luminescent materials, and the helical derivatives, B,N-embedded helicenes, have been rapidly growing recently. In this feature article, we review and summarize the synthesis and chiroptical properties of azahelicenes, which are classified into imine-type and amine-type azahelicenes and B,N-embedded helicenes. CPL switching systems of azahelicenes are also reviewed. No potential conflict of interest relevant to this article was reported.

Nature Portfolio Acta Medica Okayama 2045-2322 15 1 2025 Microfluidic fabrication of rattle shaped biopolymer microcapsules via sequential phase separation in oil droplets 6666 EN Takaichi Watanabe Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology Yuko Sakai Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology Kurumi Mori Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology Tsutomu Ono Department of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology Multilayer microcapsules containing a small particle within a larger capsule have recently attracted considerable attention owing to their potential applications in diverse fields, including drug delivery, active ingredient storage, and chemical reactions. These complex capsules have been fabricated using interfacial polymerization or seeded emulsion polymerization. However, these methods often require complex and lengthy polymerization processes, limiting their utility, particularly in biopolymer systems. This study introduces a simple and efficient approach for preparing rattle-shaped cellulose acetate (CA) microcapsules through sequential phase separation in droplets. We systematically examine the effects of various preparation parameters, including the amount of co-solvent, initial droplet size, and flow rates, and reveal that the incorporation of a co-solvent-ethyl acetate (EA)- in the dispersed phase significantly impacts the microcapsule morphology. Our findings demonstrate a transition from a core-shell to a rattle-shaped structure as the EA concentration increases. Furthermore, the initial droplet diameter and flow rates influence microcapsule formation-larger droplets and reduced continuous-phase flow rates favor the development of multi-layered structures. These results indicate that the formation mechanism of these rattle-shaped microcapsules arises from the establishment of a radial solvent concentration gradient and subsequent phase separation within the droplets, driven by kinetic rather than thermodynamic factors. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1612-1872 2025 Antifouling Activity of Xylemin, Its Structural Analogs, and Related Polyamines e202403213 EN Hiroyoshi Takamura Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Takefumi Yorisue Institute of Natural and Environmental Sciences, University of Hyogo Kenta Tanaka Research Institute for Interdisciplinary Science, Okayama University Isao Kadota Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Biofouling, which is the accumulation of organisms on undersea structures, poses significant global, social, and economic issues. Although organotin compounds were effective antifoulants since the 1960s, they were banned in 2008 due to their toxicity to marine life. Although tin-free alternatives have been developed, they also raise environmental concerns. This underscores the need for effective, nontoxic antifouling agents. We previously synthesized N-(4-aminobutyl)propylamine (xylemin) and its structural analogs. In this study, we assayed the antifouling activity and toxicity of xylemin, its structural analogs, and related polyamines toward cypris larvae of the barnacle Amphibalanus amphitrite. Xylemin and its Boc-protected analog exhibited antifouling activities with 50% effective concentrations (EC50) of 4.25 and 6.11 µg/mL, respectively. Four xylemin analogs did not show a settlement-inhibitory effect at a concentration of 50 µg/mL. Putrescine, spermidine, spermine, and thermospermine, which are xylemin-related polyamines, did not display antifoulant effects (EC50 > 50 µg/mL). All evaluated compounds were nontoxic at a concentration of 50 µg/mL. These findings indicate that the size and structure of the N-alkyl group are essential for the antifouling activity of xylemin. Therefore, xylemin and its analogs hold promise as nontoxic, eco-friendly antifouling agents, offering a sustainable solution to biofouling in marine environments. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1433-7851 64 8 2025 B,N‐Embedded Helical Nanographenes Showing an Ion‐Triggered Chiroptical Switching Function e202418546 EN Chihiro Maeda Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Sayaka Michishita Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Issa Yasutomo Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Tadashi Ema Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Intramolecular oxidative aromatic coupling of 3,6-bis(m-terphenyl-2’-yl)carbazole provided a bis(m-terphenyl)-fused carbazole, while that of 3,6-bis(m-terphenyl-2’-yl)-1,8-diphenylcarbazole afforded a bis(quaterphenyl)-fused carbazole. Borylation of the latter furnished a B,N-embedded helical nanographene binding a fluoride anion via a structural change from the three-coordinate boron to the four-coordinate boron. The anionic charge derived from the fluoride anion is stabilized over the expanded π-framework, which leads to the high binding constant (Ka) of 1×105 M－1. The four-coordinate boron species was converted back to the parent three-coordinate boron species with Ag+, and the chiroptical switch between the three-coordinate boron and four-coordinate boron species has been achieved via the ion recognition with the change in the color and glum values. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-7345 61 24 2025 Nano/microparticle-based tough and recyclable polymers toward a sustainable society 4606 4620 EN Yuma Sasaki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuichiro Nishizawa Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takuma Kureha Department of Frontier Materials Chemistry, Graduate School of Science and Technology, Hirosaki University Daisuke Suzuki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University By virtue of their unique properties, polymer nano/microparticles constitute important building blocks for the construction of functional nanomaterials. Although intense research efforts in this field have laid the foundation for the applications of polymer nano/microparticle-based latex films, cutting-edge innovations in the recycling of polymer materials are still required for the realization of a sustainable society. This feature article reviews our recent attempts to develop the applications of polymer nano/microparticles in the context of a circular society on the basis of the precise synthesis of single nano/microparticles and multiscale structural analysis. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 79 1 2025 Photoinitiators Induce Histamine Production in Human Mast Cells 51 58 EN Taro Miura Department of Clinical Pharmacy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yoichi Kawasaki Laboratory of Clinical Pharmacology and Therapeutics, Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University Hirofumi Hamano Department of Clinical Pharmacy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yoshito Zamami Department of Clinical Pharmacy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiaki Sendo Department of Clinical Pharmacy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Original Article 10.18926/AMO/68362 Photoinitiators are used in the manufacture of many daily products, and may produce harmful effects due to their cytotoxicity. They have also been detected in human serum. Here, we investigated the histamine-producing effects in HMC-1 cells and the inflammatory cytokine release effects in RAW264 cells for four photoinitiators: 1-hydroxycyclohexyl phenyl ketone; 2-isopropylthioxanthone; methyl 2-benzoylbenzoate; and 2-methyl-4´-(methylthio)-2-morpholinopropiophenone. All four promoted histamine production in HMC-1 cells; however, they did not significantly affect the release of inflammatory cytokines in RAW264 cells. These findings suggest that these four photoinitiators induce inflammatory cytokine-independent histamine production, potentially contributing to histamine-mediated chronic inflammation in vitro. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0743-7463 41 4 2025 Formation of Nanowindow between Graphene Oxide and Carbon Nanohorn Assisted by Metal Ions 2679 2687 EN Zhao Li Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Moeto Toyota Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Takahiro Ohkubo Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University This study presents a novel nanostructured material formed by inserting oxidized carbon nanohorns (CNHox) between layered graphene oxide (GO) nanosheets using metal ions (M) from nitrate as intermediates. The resulting GO–CNHox-M structure effectively mitigated interlayer aggregation of the GO nanosheets. This insertion strategy promoted the formation of nanowindows on the surface of the GO sheets and larger mesopores between the GO nanosheets, improving material porosity. Characterization revealed successful CNHox insertion, which increased interlayer spacing and reduced GO stacking. The GO–CNHox-Ca exhibited a significantly higher specific surface area (SSA) and pore volume than pure GO, with values of 374 m2 g–1 and 0.36 mL g–1, respectively. The GO–CNHox-K composite also exhibited a well-developed pore structure with an SSA of 271 m2 g–1 and pore volume of 0.26 mL g–1. These findings demonstrate that Ca2+ or K+ ions effectively link GO and CNHox, validating the success of this insertion approach in reducing GO aggregation. Metal ions played a crucial role in the insertion process by facilitating electrostatic interactions and coordination bonds between GO and CNHox. This study provides new insights into reducing GO agglomeration and expanding the application of GO-based materials. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 1756-4646 125 2025 Resveratrol, a food-derived polyphenol, promotes Melanosomal degradation in skin fibroblasts through coordinated activation of autophagy, lysosomal, and antioxidant pathways 106672 EN Saki Okamoto Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Saya Kakimaru Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mayuko Koreishi Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mika Sakamoto National Institute of Genetics, ROIS Yoshimasa Nakamura Graduate School of Environmental and Life Science, Okayama University Hideya Ando Department of Applied Chemistry and Biotechnology, Okayama University of Science Yoshio Tsujino Graduate School of Science, Technology, and Innovation, Kobe University Ayano Satoh Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Resveratrol, a polyphenol found in grapes and peanuts, is known for diverse biological activities, yet its effects on dermal hyperpigmentation (so-called dark spots) remain unexplored. We investigated resveratrol's ability to enhance melanosomal degradation in human dermal fibroblasts. At concentrations of 25-50 mu M, resveratrol increased autophagy as measured by microtubule-associated protein 1A/1B-light chain 3 (LC3)-II/LC3-I ratio and enhanced lysosomal activity as assessed by a lysosomal activity reporter system. RNA sequencing revealed upregulation of lysosomal and autophagy-related genes, including cathepsins. Furthermore, reporter assays showed resveratrol's activation of antioxidant response via nuclear factor erythroid 2-related factor 2 (NRF2)mediated, leading to upregulation of transcription factor EB/transcription factor E3 (TFEB/TFE3), master regulators of lysosomal function. In fibroblasts pre-loaded with melanosomes, resveratrol reduced melanosome content compared to control by day 3. The findings reveal the activation of interconnected autophagy, lysosomal, and antioxidant pathways by resveratrol, suggesting potential applications in functional foods targeting dermal hyperpigmentation. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1520-6106 129 2 2024 Hydronium Ions Are Less Excluded from Hydrophobic Polymer–Water Interfaces than Hydroxide Ions 726 735 EN Ryan L. Myers Department of Chemistry, The Pennsylvania State University, University Park Aoi Taira Department of Chemistry, Okayama University Chuanyu Yan Department of Chemistry, The Pennsylvania State University, University Park Seung-Yi Lee Department of Chemistry, The Pennsylvania State University, University Park Lauren K. Welsh Department of Chemistry, The Pennsylvania State University, University Park Patrick R. Ianiro Department of Chemistry, University of Pittsburgh at Bradford Tinglu Yang Department of Chemistry, The Pennsylvania State University, University Park Kenichiro Koga Department of Chemistry, Okayama University Paul S. Cremer Department of Chemistry, The Pennsylvania State University, University Park The cloud point temperatures of aqueous poly(N-isopropylacrylamide) (PNIPAM) and poly(ethylene) oxide (PEO) solutions were measured from pH 1.0 to pH 13.0 at a constant ionic strength of 100 mM. This ionic strength was reached by mixing the appropriate concentration of NaCl with either HCl or NaOH. The phase transition temperature of both polymers was nearly constant between pH 2.0 and 12.0. However, the introduction of 100 mM HCl (pH 1.0) led to an increase in the cloud point temperature, although this value was still lower than the cloud point temperature in the absence of salt. By contrast, the introduction of 100 mM NaOH (pH 13.0) caused a decrease in the cloud point temperature, both relative to adding 100 mM NaCl and adding no salt. Nuclear magnetic resonance (NMR) studies of these systems were performed below the cloud point temperature, and the chemical shifts closely tracked the corresponding changes in the phase transition temperature. Specifically, the introduction of 100 mM HCl caused the 1H chemical shift to move downfield for the CH resonances from both PNIPAM and PEO, while 100 mM NaOH caused the same resonances to move upfield. Virtually no change in the chemical shift was seen between pH 2.0 and 12.0. These results are consistent with the idea that a sufficient concentration of H3O+ led to polymer swelling compared to Na+, while substituting Cl– with OH– reduced swelling. Finally, classical all-atom molecular dynamics (MD) simulations were performed with a monomer and 5-mer corresponding to PNIPAM. The results correlated closely with the thermodynamic and spectroscopic data. The simulation showed that H3O+ ions more readily accumulated around the amide oxygen moiety on PNIPAM compared with Na+. On the other hand, OH– was more excluded from the polymer surface than Cl–. Taken together, the thermodynamic, spectroscopic, and MD simulation data revealed that H3O+ was less depleted from hydrophobic polymer/water interfaces than any of the monovalent Hofmeister metal cations or even Ca2+ and Mg2+. As such, it should be placed on the far-right side of the cationic Hofmeister series. On the other hand, OH– was excluded from the interface and could be positioned in the anionic Hofmeister series between H2PO4– and SO42–. No potential conflict of interest relevant to this article was reported.

AIP Publishing Acta Medica Okayama 0003-6951 126 1 2025 Dynamic domain motion enhancing electro-optic performance in ferroelectric films 012901 EN Shinya Kondo Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Kazuki Okamoto Department of Energy Engineering, Nagoya University Osami Sakata Japan Synchrotron Radiation Research Institute (JASRI) Takashi Teranishi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Akira Kishimoto Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takanori Nagasaki Department of Energy Engineering, Nagoya University Tomoaki Yamada Department of Energy Engineering, Nagoya University With the rapid advancement of information technology, there is a pressing need to develop ultracompact and energy-efficient thin-film-based electro-optic (EO) devices. A high EO coefficient in ferroelectric materials is crucial. However, substrate clamping can positively or negatively influence various physical properties, including the EO response of these films, thus complicating the development of next-generation thin-film-based devices. This study demonstrates that reversible dynamic domain motion, achieved through substrate clamping, significantly enhances the EO coefficient in epitaxial ferroelectric rhombohedral Pb(Zr, Ti)O3 thin films, where the (111) and (⁠ 111⁠) domains coexist with distinct optical axes. In principle, this approach can be applied to different film-substrate systems, thereby contributing to the advancement of sophisticated EO devices based on ferroelectrics. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1936-0851 18 52 2024 Bright Quantum-Grade Fluorescent Nanodiamonds 35202 35213 EN Keisuke Oshimi Department of Chemistry, Graduate School of Life, Environmental, Natural Science and Technology, Okayama University Hitoshi Ishiwata The National Institutes for Quantum Science and Technology (QST), Institute for Quantum Life Science (iQLS) Hiromu Nakashima Department of Chemistry, Graduate School of Life, Environmental, Natural Science and Technology, Okayama University Sara Mandić Department of Chemistry, Graduate School of Life, Environmental, Natural Science and Technology, Okayama University Hina Kobayashi Department of Chemistry, Graduate School of Life, Environmental, Natural Science and Technology, Okayama University Minori Teramoto Advanced Materials Laboratory, Sumitomo Electric Industries, Ltd. Hirokazu Tsuji Advanced Materials Laboratory, Sumitomo Electric Industries, Ltd. Yoshiki Nishibayashi Advanced Materials Laboratory, Sumitomo Electric Industries, Ltd. Yutaka Shikano Institute of Systems and Information Engineering, University of Tsukuba Toshu An School of Materials Science, Japan Advanced Institute of Science and Technology Masazumi Fujiwara Department of Chemistry, Graduate School of Life, Environmental, Natural Science and Technology, Okayama University Optically accessible spin-active nanomaterials are promising as quantum nanosensors for probing biological samples. However, achieving bioimaging-level brightness and high-quality spin properties for these materials is challenging and hinders their application in quantum biosensing. Here, we demonstrate bright fluorescent nanodiamonds (NDs) containing 0.6–1.3-ppm negatively charged nitrogen-vacancy (NV) centers by spin-environment engineering via enriching spin-less 12C-carbon isotopes and reducing substitutional nitrogen spin impurities. The NDs, readily introduced into cultured cells, exhibited improved optically detected magnetic resonance (ODMR) spectra; peak splitting (E) was reduced by 2–3 MHz, and microwave excitation power required was 20 times lower to achieve a 3% ODMR contrast, comparable to that of conventional type-Ib NDs. They show average spin-relaxation times of T1 = 0.68 ms and T2 = 3.2 μs (1.6 ms and 5.4 μs maximum) that were 5- and 11-fold longer than those of type-Ib, respectively. Additionally, the extended T2 relaxation times of these NDs enable shot-noise-limited temperature measurements with a sensitivity of approximately 0.28K/√Hz. The combination of bulk-like NV spin properties and enhanced fluorescence significantly improves the sensitivity of ND-based quantum sensors for biological applications. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0947-6539 31 14 2025 Graphene Oxide as a Self‐Carbocatalyst to Facilitate the Ring‐Opening Polymerization of Glycidol for Efficient Polyglycerol Grafting e202404400 EN Yajuan Zou Research Institute for Interdisciplinary Science, Okayama University Kentaro Ohkura Graduate School of Natural Science and Technology, Okayama University Israel Ortiz‐Anaya Research Institute for Interdisciplinary Science, Okayama University Ryota Kimura Graduate School of Natural Science and Technology, Okayama University Alberto Bianco Research Institute for Interdisciplinary Science, Okayama University Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Grafting carbon-based nanomaterials (CNMs) with polyglycerol (PG) improves their application potentials in biomedicine and electronics. Although “grafting from” method offers advantages over “grafting to” one in terms of operability and versatility, little is known about the reaction process of glycidol with the surface groups onto CNMs. By using graphene oxide (GO) as a multi-functional model material, we examined the reactivity of the surface groups on GO toward glycidol molecules via a set of model reactions. We reveal that carboxyl groups spontaneously react with the epoxide ring with no need of catalyst, while GO catalyzes the reactions of hydroxyl groups with the epoxide of glycidol. In addition, the hydroxyl group of glycidol can open the epoxide in the basal plane of GO. The subsequent polymerization of PG is supposed to propagate at the primary and/or the secondary hydroxyl groups, generating a ramified PG macromolecule with random branch-on-branch topology. In addition, ketones, benzyl esters and aromatic ethers are found not to react with glycidol even in the presence of GO, while the aldehydes are easily oxidized into carboxyl groups under ambient condition, behaving then as the carboxyl groups. Our findings pose the foundation for understanding the polymerization mechanism of PG on CNMs. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2635-0998 2 3 2023 All-in-one terahertz taste sensor: integrated electronic and bioelectronic tongues 620 626 EN Jin Wang Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Kenji Sakai Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Toshihiko Kiwa Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Taste sensors, also known as electronic tongues or bioelectronic tongues, are designed to evaluate food and beverages, as well as for medical diagnostics. These devices mimic the ability of the human tongue to detect and identify different tastes in liquid samples, such as sweet, sour, salty, bitter, and umami. In this study, a novel all-in-one terahertz taste sensor was proposed, which differs from traditional electrochemical approaches. This sensor utilizes terahertz technology for imaging and sensing chemical reactions on the terahertz semiconductor emitter surface. The surface can be functionalized with ion-sensitive membranes, proteins, DNA aptamers, and organic receptors, enabling the detection of various substances, such as solution pH, physiological ions, sugars, toxic chemicals, drugs, and explosives. Terahertz taste sensors offer several advantages, including being label-free, high sensitivity and selectivity, rapid response, minimal sample consumption, and the ability to detect non-charged chemical substances. By integrating multiple receptors or sensing materials on a single chip, the all-in-one terahertz taste sensor has significant potential for future taste substance detection, nutrition evaluation, metabolite and drug monitoring, and biomarker sensing. No potential conflict of interest relevant to this article was reported.

AIP Publishing Acta Medica Okayama 0021-9606 159 19 2023 Efficiency and energy balance for substitution of CH4 in clathrate hydrates with CO2 under multiple-phase coexisting conditions 194504 EN Hideki Tanaka Research Institute for Interdisciplinary Science, Okayama University Masakazu Matsumoto Research Institute for Interdisciplinary Science, Okayama University Takuma Yagasaki Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University Many experimental and theoretical studies on CH4–CO2 hydrates have been performed aiming at the extraction of CH4 as a relatively clean energy resource and concurrent sequestration of CO2. However, vague or insufficient characterization of the environmental conditions prevents us from a comprehensive understanding of even equilibrium properties of CH4–CO2 hydrates for this substitution. We propose possible reaction schemes for the substitution, paying special attention to the coexisting phases, the aqueous and/or the fluid, where CO2 is supplied from and CH4 is transferred to. We address the two schemes for the substitution operating in three-phase and two-phase coexistence. Advantages and efficiencies of extracting CH4 in the individual scheme are estimated from the chemical potentials of all the components in all the phases involved in the substitution on the basis of a statistical mechanical theory developed recently. It is found that although substitution is feasible in the three-phase coexistence, its working window in temperature–pressure space is much narrower compared to the two-phase coexistence condition. Despite that the substitution normally generates only a small amount of heat, a large endothermic substitution is suggested in the medium pressure range, caused by the vaporization of liquid CO2 due to mixing with a small amount of the released CH4. This study provides the first theoretical framework toward the practical use of hydrates replacing CH4 with CO2 and serves as a basis for quantitative planning. No potential conflict of interest relevant to this article was reported.

AIP Publishing Acta Medica Okayama 0021-9606 161 21 2024 The nature of the hydrophobic interaction varies as the solute size increases from methane’s to C60’s 214501 EN Hidefumi Naito Department of Chemistry, Faculty of Science, Okayama University Tomonari Sumi Department of Chemistry, Faculty of Science, Okayama University Kenichiro Koga Department of Chemistry, Faculty of Science, Okayama University The hydrophobic interaction, often combined with the hydrophilic or ionic interactions, makes the behavior of aqueous solutions very rich and plays an important role in biological systems. Theoretical and computer simulation studies have shown that the water-mediated force depends strongly on the size and other chemical properties of the solute, but how it changes with these factors remains unclear. We report here a computer simulation study that illustrates how the hydrophobic pair interaction and the entropic and enthalpic terms change with the solute size when the solute–solvent weak attractive interaction is unchanged with the solute size. The nature of the hydrophobic interaction changes qualitatively as the solute size increases from that of methane to that of fullerene. The potential of mean force between small solutes has several well-defined extrema, including the third minimum, whereas the potential of mean force between large solutes has the deep contact minimum and the large free-energy barrier between the contact and the water-bilayer separated configurations. The difference in the potential of mean force is related to the differences in the water density, energy, and hydrogen bond number distributions in the vicinity of the pairs of hydrophobic solutes. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1523-7060 26 51 2024 Electrogenerated Lewis Acid-Catalyzed Claisen Rearrangement of Allyl Aryl Ethers 11111 11116 EN Yuta Niki Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Koichi Mitsudo Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Eisuke Sato Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Seiji Suga Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Catalysts for Claisen rearrangement have been intensively studied to overcome the need for high temperature. However, previous studies have encountered challenges, such as the need for heating, a long reaction time, and/or the need for equivalent amounts of catalyst. In this study, we introduce an effective electrogenerated boron-based Lewis acid catalyst for the aromatic Claisen rearrangement, which proceeds in a few minutes at ambient temperature. Generation of the electrogenerated Lewis acid catalyst is discussed based on NMR analysis and DFT calculations. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 2193-5807 14 2 2024 Potassium tert-Butoxide-Mediated Ring-Opening of Indolines: Concise Synthesis of 2-Vinylanilines e202400552 EN Keisuke Tokushige Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shota Asai School of Pharmacy, Shujitsu University Takumi Abe Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University A concise and metal-free procedure has been developed for the synthesis of 2-vinylanilines. Reactions of indolines with tert-BuOK in DMSO afford the decorated 2-vinylanilines in yields up to 92 %. In addition, the 2, or 3-substituted indolines could be converted to trisubstituted alkenes. Also, the protocol can be scaled to afford gram quantities of the decorated 2-vinylanilines. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2076-3417 14 23 2024 Preparation of Nano- and Microparticles Obtained from Polymerization Reaction and Their Application to Surface Coating of Woody Materials 11326 EN Toshinori Shimanouchi Department of Environmental Chemistry and Materials, Okayama University, Daichi Hirota Department of Environmental Chemistry and Materials, Okayama University, Masafumi Yoshida Department of Environmental Chemistry and Materials, Okayama University, Kazuma Yasuhara Division of Materials Science, Nara Institute of Science and Technology (NAIST) Yukitaka Kimura Department of Environmental Chemistry and Materials, Okayama University, A surface coating of polymer particles of different hydrophobicity and wide-ranged size is helpful for the surface modification of materials such as woody thin board (WTB) derived from biomass. A preparation method for polymer particles was, in this study, proposed using a capillary-type flow system. Under hydrothermal conditions, the refinement of dispersed oil droplets in water (O/W emulsions) and the polymerization reaction could be simultaneously advanced, and polymer particles of polystyrene (PS), polyvinyl alcohol (PVA), polymethyl methacrylate (PMMA), and poly-L-lactic acid (PLLA) with a particle size of about 100 nm could be synthesized. The coating of polymer particles gave an improved effect on the water repellency of WTBs due to the hydrophobicity of polymer particles and an alteration of surface roughness, and it also provided long-term stability (more than 6 years). No potential conflict of interest relevant to this article was reported.

Beilstein-Institut Acta Medica Okayama 1860-5397 20 2024 Ceratinadin G, a new psammaplysin derivative possessing a cyano group from a sponge of the genus Pseudoceratina 3215 3220 EN Shin-Ichiro Kurimoto Faculty of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Kouta Inoue Showa Pharmaceutical University Taito Ohno Showa Pharmaceutical University Takaaki Kubota Faculty of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University A new psammaplysin derivative, ceratinadin G (1), was obtained from the Okinawan marine sponge Pseudoceratina sp., and the gross structure was clarified through spectroscopic and spectrometric analyses. The absolute configuration of compound 1 was established by comparing its NMR and ECD data with those of the known psammaplysin derivative, psammaplysin F (2). Ceratinadin G (1) is a rare nitrile containing a cyano group as aminoacetonitrile, and is the first psammaplysin derivative possessing a cyano group. In vitro assays indicated that compound 1 displayed moderate cytotoxicity against L1210 murine leukemia cells and KB epidermoid carcinoma cells. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-7345 61 1 2025 Terpolymerization reactions of epoxides, CO2, and the third monomers toward sustainable CO2-based polymers with controllable chemical and physical properties 46 60 EN Koichi Nakaoka Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Tadashi Ema Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Carbon dioxide (CO2) serves as a cheap, abundant, and renewable C1 building block for the synthesis of organic compounds and polymers. Selective and efficient CO2 fixation processes are still challenging because of the kinetic and thermodynamic stability of CO2. Among various CO2 fixation processes, the ring-opening copolymerization (ROCOP) of epoxides and CO2 gives aliphatic polycarbonates with high atom economy, although the chemical and physical properties of the resulting polycarbonates are not necessarily satisfactory. Introducing the third monomers into this ROCOP system provides new terpolymers, and the thermal, optical, mechanical or degradation properties can be added or tuned by incorporating new polymer backbones derived from the third monomers at the expense of the CO2 content. Here we review the terpolymerization reactions of epoxides, CO2, and the third monomers such as cyclic anhydrides, lactones, lactides, heteroallenes, and olefins. The development of catalysts and the control of the polymer structures are described together with the chemical and physical properties of the resulting polymers. No potential conflict of interest relevant to this article was reported.