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 0017-9310 264 2026 Improving thermal stability of a microcavity emitter for utilization under atmospheric environment 128798 EN Kazuma Isobe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Shota Morishige Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Taiyo Sato Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yutaka Yamada Faculty of Environmental, Life, Natural Science and Technology, Okayama University Akihiko Horibe Faculty of Environmental, Life, Natural Science and Technology, Okayama University With the development of micro-fabrication technology, various metamaterials with controlled emission spectra have been proposed as thermal emitters. However, general metamaterials have a risk of deformations and degradation at high temperatures in atmospheric conditions, which is inconvenient for use as a thermal emitter. In this study, we propose a concept to enhance the thermal durability of microcavity-type metamaterials. Although typical microcavities are entirely composed of metal to excite the resonance of electromagnetic waves, we assessed the feasibility of a microcavity consisting of silicon with minimal metal coatings. While usual metals are oxidized at high temperatures, gold is rarely oxidized due to its chemical stability. However, the gold layer deposited on the Si substrate has the potential to melt below 400 °C due to the formation of an Au-Si eutectic alloy, which has a much lower melting point than pure gold. Therefore, we focused on the gold-tungsten bilayer as a suitable metal coating for the silicon microcavity, thereby preventing oxidation and melting that would otherwise influence the emission spectra of the thermal emitter. The numerical analysis ensured that the proposed microcavity exhibited electromagnetic resonance, similar to that of a microcavity entirely composed of metal, unless the metal coating was too thin. The fabricated microcavity with the gold-tungsten coating also exhibited a thermal emission within a limited wavelength range, due to the microcavity resonance. Moreover, the heating experiment revealed that the microcavity with a gold-tungsten coating maintained its emissivity even when heated to 400 °C, which is higher than the oxidation point of tungsten and the melting point of the Au-Si eutectic alloy. Consequently, the gold-tungsten coating would be a reasonable approach to improve the stability of the microcavity-type metamaterial at high temperatures under oxidative conditions. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0971-5894 2026 Suppression of salt-enhanced apoplastic flow by salicylic acid in rice EN Md. Asadulla Al Galib Graduate School of Environmental and Life Science, Okayama University Maoxiang Zhao Graduate School of Environmental and Life Science, Okayama University Toshiyuki Nakamura Graduate School of Environmental and Life Science, Okayama University Yoshimasa Nakamura Graduate School of Environmental and Life Science, Okayama University Yoshihiko Hirai Graduate School of Environmental and Life Science, Okayama University Yoshitaka Nakashima Graduate School of Environmental and Life Science, Okayama University Shintaro Munemasa Graduate School of Environmental and Life Science, Okayama University Izumi C. Mori Institute of Plant Science and Resources, Okayama University Yoshiyuki Murata Graduate School of Environmental and Life Science, Okayama University Salinity enhances apoplastic flow, resulting in an increment of Na+ uptake and a lower K+/Na+ ratio. Salicylic acid (SA) plays an important role in improving salinity tolerance in plants. The effect of exogenous SA on apoplastic flow in salt-treated rice seedlings was studied using an apoplastic tracer, 8-hydroxy-1,3,6-pyrenetrisulphonic acid (PTS) in light. Application of NaCl at 25 mM to the hydroponic solution significantly increased PTS uptake, while 25 mM NaCl did not affect seedling growth. Application of 25 mM NaNO3 increased PTS uptake to the same degree. Salinity significantly increased sodium (Na+) content but had no significant effect on potassium (K+) content, resulting in a lower K+/Na+ ratio. The application of SA at 0.05 mM and 0.1 mM to the hydroponic solution reduced Na-enhanced PTS uptake. Salicylic acid at 0.05 mM and 0.1 mM significantly reduced Na+ content and slightly increased K+ content in the shoots of rice seedlings, resulting in a higher K+/Na+ ratio. However, SA at up to 0.1 mM did not increase SA contents in shoots under salt stress. These results suggest that exogenous SA reduces Na+ uptake by suppressing Na+-enhanced apoplastic flow in rice seedlings. These findings provide insight into modulation of Na+ transport pathways from roots to shoots by SA and may allow us to utilize brackish water for rice cultivation and to improve salt-tolerant rice through suppression of salt-enhanced apoplastic flow by chemicals such as salicylic acid. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2662-4435 7 1 2026 Stability and distribution of dense hydrous magnesium silicates in the mantle transition zone under low water activity conditions 265 EN Yunke Song Key Laboratory of High-temperature and High-pressure Study of the Earth’s Interior, Institute of Geochemistry, Chinese Academy of Sciences Xinzhuan Guo State Key Laboratory of Critical Mineral Research and Exploration, Institute of Geochemistry, Chinese Academy of Sciences Kuan Zhai Key Laboratory of High-temperature and High-pressure Study of the Earth’s Interior, Institute of Geochemistry, Chinese Academy of Sciences Wei Guo State Key Laboratory of Geomicrobiology and Environmental Changes, School of Earth Sciences, China University of Geosciences (Wuhan) Takashi Yoshino Institute for Planetary Materials, Okayama University Water plays a central role in controlling the physical and chemical properties of Earth’s deep interior. It remains uncertain how water is stored in subducting slabs within the mantle transition zone, between depths of about 410 and 660 kilometers, and whether dense hydrous magnesium silicates act as major water carriers to greater depths. Here we report high-pressure and high-temperature laboratory experiments on the Mg-Si-H system at pressures of 16 and 21.5 GPa and a temperature of 1400 K to evaluate hydrous phase stability under transition zone conditions. We find that when bulk water content is below 1.22 wt%, H2O is predominantly incorporated into wadsleyite and ringwoodite rather than forming dense hydrous magnesium silicates. Because estimated water contents in subducted oceanic slabs are typically lower than one weight percent, formation of these silicates is unlikely, suggesting that the mantle transition zone may restrict large scale water transport into the lower mantle. 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.

Elsevier BV Acta Medica Okayama 0923-1811 119 1 2025 Big data-driven target identification by machine learning: DRD2 as a therapeutic target for psoriasis 9 17 EN Takashi Sakai Department of Dermatology, Faculty of Medicine, Oita University Ryusuke Sawada Department of Pharmacology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Otoha Ichinose Department of Bioscience and Bioinformatics, Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology Takeshi Terabayashi Department of Pharmacology, Faculty of Medicine, Oita University Yutaka Hatano Department of Dermatology, Faculty of Medicine, Oita University Yoshihiro Yamanishi Department of Complex Systems Science, Graduate School of Informatics, Nagoya University Toshimasa Ishizaki Department of Pharmacology, Faculty of Medicine, Oita University Background: The development of medical treatments has traditionally relied on researchers leveraging scientific knowledge to hypothesize disease mechanisms and identify therapeutic agents. However, the depletion of novel therapeutic targets has become a significant challenge, resulting in stagnation within pharmaceutical research.<br> Objective: To address the scarcity of therapeutic targets, we developed a machine learning (ML)-based system capable of predicting therapeutic target molecules for diseases. To validate its utility, we applied this system to psoriasis, aiming to identify novel treatment strategies.<br> Methods: Our approach utilized a large clinical database to calculate reporting odds ratios for all drugs associated with the prevention of diseases of interest. We identified target proteins by analyzing large chemical structure databases to discover proteins commonly associated with preventive drug candidates. Experimental validation was conducted by administering a predicted therapeutic candidate in an imiquimod-induced psoriasis mouse model.<br> Results: The ML-based predictions identified drugs for Parkinson’s disease as potential preventive candidates for psoriasis. Further analysis highlighted dopamine receptor D2 (DRD2) as a therapeutic target. Administration of a DRD2 agonist alleviated psoriasis symptoms in mice, evidenced by the downregulation of mRNA expression in the IL-17 pathway and reduced serum tumor necrosis factor-α levels.<br> Conclusion: This study demonstrates the utility of a novel ML-based system for identifying therapeutic targets, as shown by its successful application in uncovering the role of DRD2 in psoriasis. Beyond psoriasis, this system offers significant potential for exploring pathological mechanisms and discovering therapeutic targets across various diseases. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2470-1343 11 9 2026 Water-Resistant Antibacterial Coatings Using Cetylpyridinium Chloride - Graphene Oxide Composites 14570 14577 EN Keisuke Okubo Department of Periodontics and Endodontics, Field of Medical Development, Okayama University Gen Kano Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masato Komoda Research Institute for Interdisciplinary Science, Okayama University Kazuhiro Omori Department of Pathophysiology - Periodontal Science, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Shogo Takashiba Department of Pathophysiology - Periodontal Science, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hospital-acquired infections remain a persistent threat in healthcare settings, especially with the increasing number of elderly and immunocompromised patients. In situations where the use of disposable materials is difficult, durable antibacterial surface coatings are essential. In this study, we report the structural characterization of cetylpyridinium chloride-graphene oxide (CPC–GO) hybrid materials and the sustainability of their antibacterial effects, aiming at washable antibacterial coatings for medical applications. Graphene oxide (GO) has a large surface area and numerous functional groups, while cetylpyridinium chloride (CPC) is a quaternary ammonium compound with well-documented antibacterial activity. We hypothesized that the stable incorporation of CPC through the functional groups of GO could improve surface retention and provide long-term antibacterial performance. The structural properties of the CPC–GO composites were characterized by UV–vis spectroscopy, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, and atomic force microscopy. These analyses confirmed the formation of a complex through ionic bonds and the maintenance of a planar composite structure. The antibacterial performance of the CPC–GO coatings was examined using representative bacteria. Notably, the CPC–GO coatings maintained their antibacterial activity significantly better than the negative controls even after multiple washings. The excellent surface retention of the CPC–GO composite suggests its potential as a next-generation antibacterial coating for areas where disinfection and sterilization are impossible, such as the interior of complex medical devices. This study suggests a strategy to extend the efficacy of existing antibacterial agents through the application of nanomaterials. Future studies will focus on the controlled release, long-term stability, and biocompatibility of CPC to realize clinical applications. No potential conflict of interest relevant to this article was reported.

岡山大学理学部地球科学科 Acta Medica Okayama 1340-7414 32 1 2026 寒風古窯跡群須恵器の岩石学的研究 9 19 EN Taiji ANAMI Department of Earth Sciences, Okayama University Toshio NOZAKA Department of Earth Sciences, Okayama University Osamu KIMURA Department of Archaeology, Osaka University 10.18926/ESR/70295 　The Sabukaze kiln site, a representative ancient tunnel-kiln site in the Kibi region, worked during the Asuka period (from early 7th century to early 8th century) to produce Sue ware including jars, cups, coffins, and ornamental tiles. To determine the provenance of the materials used for the Sue ware, we carried out petrological analyses of 13 Sue sherds, including optical microscopy, X-ray diffractometry, X-ray fluorescence spectroscopy, Raman spectroscopy, and electron-probe analysis. In spite of the difference of production time, all the Sue sherds show close similarities in modal proportion of mineral inclusions with dominant quartz and feldspar, and minor volcanic glass, in chemical compositions of feldspar and interstitial matrix, and in whole-sherd chemical composition. These similarities suggest that the paste materials of the Sabukaze Sue ware were commonly derived from weathered rhyolitic rocks and obtained from the same or neighboring mining site(s) located near the kiln site. 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.

Springer Science and Business Media LLC Acta Medica Okayama 0969-0239 32 16 2025 Development of sulfation for cellulose pulp to change its fiber morphology and appearance to transparent in water 9663 9677 EN Ayato Nishimura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tetsuya Uchida Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Cellulose pulp (CP) is composed mainly of cellulose which is one of the most useful and sustainable natural polymers. Cellulose-based materials, such as completely dispersed nanofibers and water-soluble cellulose, are transparent in water. Additionally, chemical modification of CP has been employed as a pretreatment for the preparation of nanofibers and to impart absorption properties derived from anionic functional groups. However, little is known about chemically modified CPs comprising micron-scale fibers that are transparent in water.In this study, we synthesized transparent sulfated cellulose pulp (TSCP) that exhibits good dispersion stability, high transparency in water, and highly swollen fiber structures. The sulfation method involved heating sulfamic acid and urea supported on CP. TSCP synthesized using a sulfamic acid amount relative to CP (Q) of 18.5, a molar ratio of urea to sulfamic acid (R) of 0.80, and a reaction temperature of 140 °C exhibited the highest total light transmittance (94.7%) in water, a degree of polymerization (535), and amount of sulfate groups (1.73 mmol/g). Polarization microscopy confirmed that most TSCP fibers swelled in water along the fiber width direction. The structure of hydrous-state TSCP was further confirmed using low-vacuum scanning electron microscopy. The maximum fiber width of the swollen TSCP reached 122 μm, which was approximately six times than that of CP. The crystallinity was equivalent to that of the original CP with a Cellulose I-type crystalline structure. This transparent, hydrous-state TSCP, comprising predominantly swollen CP fibers, demonstrates potential for applications as a transparent material. No potential conflict of interest relevant to this article was reported.

Frontiers Media SA Acta Medica Okayama 1664-462X 16 2025 Structural analysis of PSI-ACPI and PSII-ACPII supercomplexes from a cryptophyte alga Rhodomonas sp. NIES-2332 1716939 EN Wenyue Zhang Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nozomi Yonehara Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Mizuki Ishii Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haowei Jiang Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Romain La Rocca Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Pi-Cheng Tsai Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hongjie Li Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Koji Kato Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Fusamichi Akita Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Jian-Ren Shen Advanced Research Field, Research Institute for Interdisciplinary Science, and Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Light energy is converted to chemical energy by two photosystems (PSI and PSII) in complex with their light-harvesting complex proteins (LHCI and LHCII) in photosynthesis. Rhodomonas is a member of cryptophyte alga whose LHCs contain unique chlorophyll a/c proteins (ACPs) and phycobiliproteins. We purified PSI-ACPI and PSII-ACPII supercomplexes from a cryptophyte Rhodomonas sp. NIES-2332 and analyzed their structures at high resolutions of 2.08 Å and 2.17 Å, respectively, using cryo-electron microscopy. These structures are largely similar to those reported previously from two other species of cryptophytes, but exhibited some differences in both the pigment locations and subunit structures. A part of the antenna subunits of both photosystems is shifted compared with the previously reported structures from other species of cryptophytes, suggesting some differences in the energy transfer rates from the antenna to the PSI and PSII cores. Newly identified lipids are found to occupy the interfaces between the antennae and cores, which may be important for assembly and stabilization of the supercomplexes. Water molecules surrounding three iron-sulfur clusters of the PSI core are found in our high-resolution structure, some of which are conserved from cyanobacteria to higher plants but some are different. In addition, our structure of PSII-ACPII lacks the subunits of oxygen-evolving complex as well as the Mn4CaO5 cluster, suggesting that the cells are in the S-growth phase, yet the PSI-ACPI structure showed the binding of PsaQ, suggesting that it is in an L-phase. These results suggest that the S-phase and L-phase can co-exist in the cryptophytic cells. The high-resolution structures of both PSI-ACPIs and PSII-ACPIIs solved in this study provide a more solid structural basis for elucidating the energy transfer and quenching mechanisms in this group of the organisms. 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.

MDPI AG Acta Medica Okayama 1996-1944 19 3 2026 Effect of Surface Morphology Formed by Additive Manufacturing on the Adhesion of Dental Cements to Zirconia 563 EN Kumiko Yoshihara National Institute of Advanced Industrial Science and Technology (AIST), Health and Medical Research Institute Noriyuki Nagaoka Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School Sungho Lee National Institute of Advanced Industrial Science and Technology (AIST) Yukinori Maruo Department of Prosthodontics, Okayama University Fiona Spirrett Joining and Welding Research Institute, Osaka University Soshu Kirihara Joining and Welding Research Institute, Osaka University Yasuhiro Yoshida Department of Biomaterials and Bioengineering, Faculty of Dental Medicine, Hokkaido University Bart Van Meerbeek Department of Oral Health Sciences, BIOMAT, KU Leuven Background: Durable bonding to zirconia remains difficult because its chemically inert surface resists acid etching. Additive manufacturing (AM) enables controlled surface morphology, which may enhance micromechanical retention without additional treatments. Methods: Zirconia specimens with three AM-derived surface designs—(1) concave–convex hemispherical patterns, (2) concave hemispherical patterns, and (3) as-printed surfaces—were fabricated using a slurry-based 3D printing system and sintered at 1500 °C. Zirconia specimens fabricated by subtractive manufacturing using CAD/CAM systems, polished with 15 µm diamond lapping film and with or without subsequent alumina sandblasting, served as controls. Surface morphology was analyzed by FE-SEM, and shear bond strength (SBS) was tested after cementation with a resin-based luting agent. Results: SEM revealed regular layered textures and designed hemispherical structures (~300 µm) in AM specimens, along with step-like irregularities (~40 µm) at layer boundaries. The concave–convex AM group showed significantly higher SBS than both sandblasted and polished subtractive-manufactured zirconia (p < 0.05). Vertically printed specimens demonstrated greater bonding strength than those printed parallel to the bonding surface, indicating that build orientation affects resin infiltration and interlocking. Conclusion: AM-derived zirconia surfaces can provide superior and reproducible micromechanical retention compared with conventional treatments. Further optimization of printing parameters and evaluation of long-term durability are needed for clinical application. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2352-409X 70 2026 A semi-quantitative archaeothermometer based on feldspar and volcanic glass compositions in ancient ceramics from the Kibi region, Japan 105566 EN Toshio Nozaka Department of Earth Sciences, Okayama University Naoya Ohbayashi Department of Earth Sciences, Okayama University Yuki Toda Department of Earth Sciences, Okayama University Taiji Anami Department of Earth Sciences, Okayama University Kanako Sugiura Department of Archaeology, Okayama University Takahiro Nozaki Research Institute for the Dynamics of Civilizations, Okayama University Osamu Kimura Research Institute for the Dynamics of Civilizations, Okayama University Naoko Matsumoto Research Institute for the Dynamics of Civilizations, Okayama University Akira Seike Department of Archaeology, Okayama University In this study, we analyzed the chemical compositions of feldspar and volcanic glass clasts in haniwa from kofuns and Sue ware from the Sabukaze kiln site, both in the Kibi region, southwestern Japan, to estimate the thermal conditions of ceramic firing in the 5th–8th centuries CE. Based on the coexistence of molten and unmolten feldspar rims, the solidus temperatures were estimated at ∼ 1050°C–1150°C for haniwa and ∼ 1150°C–1200°C for Sue ware. Volcanic glass compositions changed systematically during firing, showing increases in K2O and decreases in Na2O. From these observations, we propose a semi-quantitative archaeothermometer using variations in the K/Na molar ratio of volcanic glass within a ceramic matrix. This approach can be applied to investigate the development of kiln-firing in the Kibi region, the existence of haniwa potters employing different firing methods, variation in heat input for producing Sue vessels of differing sizes or functions, and temperature-controlled practices in Sue ware production. 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.

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.

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.<br> 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.<br> 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.<br> 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.

American Chemical Society (ACS) Acta Medica Okayama 0006-2960 64 20 2025 Characterization of Autonomous and Ca2+/Calmodulin-Dependent Activities of CaMKK Isoforms In Vitro and in Mouse Tissues 4309 4317 EN Satomi Ohtsuka Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Yerun Chen 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 Teruhiko Ishikawa Department of Science Education, Graduate School of Education, Okayama University Hiroyuki Sakagami Department of Anatomy, Kitasato University School of Medicine Futoshi Suizu Clinical Examination Department, Kagawa Prefectural University of Health Sciences Hiroshi Tokumitsu Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Ca2+/CaM-dependent protein kinase kinase (CaMKK) phosphorylates and activates downstream kinases, including CaMKI, CaMKIV, PKB, and AMPK, regulating various cellular functions such as neuronal morphogenesis, metabolic control, and pathophysiological pathways, such as cancer progression. CaMKKα/1 is tightly regulated by an autoinhibitory mechanism. CaMKKβ/2 activity is highly Ca2+/CaM-independent (autonomous activity) in vitro and Ca2+/CaM-dependent in cultured cells. Whether these two activity states of CaMKKβ/2 exist in vivo and the detailed regulatory mechanisms for the transition of both activity states remain unclear due to the difficulty in distinguishing the two activity states. In this study, we detected Ca2+-dependent and autonomous CaMKK activity in HeLa cells and successfully separated both activity states of CaMKKβ/2 in mouse brain and testis extracts using a recently developed CaMKK inhibitor (TIM-063)-coupled sepharose, which binds to the catalytic domain in the active state but not in the autoinhibited state. Furthermore, lambda protein phosphatase treatment converted the Ca2+/CaM-dependent form to the autonomous form of CaMKKβ/2, which was not affected by Ala mutation of Ser128, Ser132, and Ser136. The two activity forms of CaMKKβ/2 had equivalent Ca2+/CaM-binding ability. The findings demonstrate the presence of autonomous and Ca2+/CaM-dependent forms of CaMKKβ/2 independently in mouse tissues and cultured cells. The transition of these states of CaMKKβ/2 may be dynamically regulated by the phosphorylation/dephosphorylation of serine residues in the N-terminal regulatory domain. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0009-2541 695 2025 Flash vaporization and migration of iodine in the oceanic plate subduction zone 123031 EN Noriyuki Suzuki Department of Earth and Planetary Sciences, Faculty of Science, Hokkaido University Jun Kameda Institute for Planetary Materials, Okayama University Miki Amo Geology and Geophysics Division, Technology Department, Japan Organization for Metals and Energy Security Crustal fluids in subduction zones, such as subsurface aquifers, submarine seeps, and gas hydrate waters, are often rich in iodine (I2) and methane (CH4). Large-scale aquifers in the Kanto subduction zone, where the Pacific Plate (PAC) and the Philippine Sea Plate (PHS) are subducting, also exhibit high concentrations of I2 and CH4. However, the origin and behavior of I2 in the subduction zone are unclear, and its coexistence with CH4 remains unresolved. To investigate this, we compiled the I2 phase diagram under high-pressure and high-temperature (P–T) conditions to predict its physicochemical properties in the subduction zone. We then applied the P–T paths of subducted PAC and PHS sediments to the I2 phase diagram. Our findings reveal that I2 can exist as a liquid in the young and hot PHS subduction zone. Transient decompressions during earthquake ruptures can cause liquid iodine to flash-vaporize and be expelled from subducted sediments. Along with I2, thermogenic CH4 and hydrogen (H2) generated in the subducted sediments are also released and transported upward, likely by slab-dehydrated fluids. Additionally, H2 may enhance microbial CH4 production through hydrogenotrophic methanogenesis. In subduction zones of young and hot oceanic plates such as the PHS, crustal fluids are enriched in I2 and coexist with CH4 owing to the simultaneous expulsion of I2, CH4, and H2 from the same subducted sediments and their migration via deep fluids. Large subsurface aquifers can act as traps and reservoirs for migrating I2 and CH4, forming large-scale I2 and CH4 deposits. No potential conflict of interest relevant to this article was reported.

Iron and Steel Institute of Japan Acta Medica Okayama 0915-1559 65 13 2025 Heat Transfer Enhancement by Forming Bridges among Reactive Particles in a Packed Bed Reactor of a Solid-gas Chemical Heat Storage System 2097 2104 EN Koichi Nakaso Faculty of Environmental, Life Natural Science and Technology, Okayama University Kenji Shimada Graduate School of Natural Science and Technology, Okayama University Yasushi Mino Faculty of Environmental, Life Natural Science and Technology, Okayama University Kuniaki Gotoh Faculty of Environmental, Life Natural Science and Technology, Okayama University In this study, the enhancement of the thermal output of solid-gas chemical heat storage systems was investigated. Bridges made of high-thermal conductivity materials were formed among reactive particles by drying a slurry which contained graphite powder as a thermal additive and dispersant in a packed-bed reactor. First, the effect of the volume ratio of the dispersant on effective thermal conductivity was investigated. The optimum volume ratio of dispersant to graphite powder was determined. Furthermore, repetitive bridge formation increased the effective thermal conductivity. Based on these results, we investigated the thermal response of the energy-discharge process. Consequently, the temperature distribution in the radial direction of the reactor decreased owing to the formation of bridges. In addition, the thermal energy generated by the adsorption of water vapor onto the adsorbent was effectively transferred to the reactor wall. The thermal output was estimated based on the experimental results. The thermal output was increased by the formation of bridges. No potential conflict of interest relevant to this article was reported.

Japanese Society for Horticultural Science Acta Medica Okayama 2189-0102 94 3 2025 Effect of Storage Temperature and a Sugar-ester Edible Coating on Postharvest Quality and Storage Life of ‘Fuyu’ Persimmon (Diospyros kaki Thunb.) 401 407 EN Maqsood Muqadas Graduate School of Environmental, Life Science, Natural Science and Technology Okayama University Oscar W. Mitalo Faculty of Life and Environmental Sciences, University of Tsukuba Kyohei Ohashi Graduate School of Environmental, Life Science, Natural Science and Technology Okayama University Takumi Otsuki Graduate School of Environmental, Life Science, Natural Science and Technology Okayama University Chikara Yano Graduate School of Environmental, Life Science, Natural Science and Technology Okayama University Ziaurrahman Hejazi Graduate School of Agriculture, University of Miyazaki Natsuki Hira Shiga R&amp;D Center, Mitsubishi Chemical Corporation Koichiro Ushijima Graduate School of Environmental, Life Science, Natural Science and Technology Okayama University Yasutaka Kubo Graduate School of Environmental, Life Science, Natural Science and Technology Okayama University In ‘Fuyu’ persimmons (Diospyros kaki Thunb.), crunchiness is a preferred postharvest attribute among both distributors and consumers. The present study first examined softening characteristics during storage at 0, 5, 10, 15, 20, and 25°C. Fruit stored at 0°C remained firm for 84 d, while that stored at 5°C had a 100% softening rate within 35 d. At 10 and 15°C, over 70% of fruit softened within 49 d and 63 d, respectively. The softening rate was relatively slower at 20 and 25°C, with only 27% softened fruit after 56 d at 25°C. The potential of a newly developed sugar-ester (SE) edible coating to delay fruit softening and maintain postharvest quality was then assessed during storage at 0 and 25°C. Uncoated fruit stored at 0°C for 56 d developed chilling injury (CI) symptoms (rapid fruit softening and peel browning) within 2 d of rewarming at 20°C. These CI symptoms were notably mitigated in SE-coated fruit. At 25°C, SE coating also delayed fruit softening and peel color change in addition to reducing fruit shrinkage. In conclusion, in ‘Fuyu’ persimmons ambient temperature (20–25°C) storage in combination with an edible SE coating is recommended for the high demand Christmas and new year seasons and 0°C storage with an edible SE coating is suitable for longer storage and distribution. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2452-199X 57 2026 Robust adhesion between solid-state hydroxyapatite and bone tissue through surface demineralization 632 645 EN Shichao Xie Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masahiro Okada Division of Biomaterials Science and Engineering, Graduate School of Dentistry, Tohoku University Haruyuki Aoyagi Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihisa Otaka Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Xiaofeng Yang Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takayoshi Nakano Division of Materials and Manufacturing Science, Graduate School of Engineering, The University of Osaka Takuya Matsumoto Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Objective: Current bone adhesives typically lack adequate mechanical strength, long-term stability, or biocompatibility. To address these limitations, we designed a new adhesion strategy using a solid-state hydroxyapatite (HAp) adhesive in combination with bone surface demineralization.<br> Methods: Solid-state HAp adhesives were synthesized via wet chemical precipitation and heat treatment. Cortical bone specimens were partially demineralized with phosphoric acid (H3PO4) or ethylenediaminetetraacetic acid (EDTA), and characterized using scanning electron microscopy (SEM) and attenuated total reflectance–Fourier transform infrared spectroscopy (ATR-FTIR). Shear adhesion strength of HAp to demineralized bone was measured over time. In vivo fixation was assessed in rats using micro-computed tomography and histology. Statistical analysis used Tukey-Kramer tests after normality and variance checks.<br> Results: Although the HAp adhesive failed to adhere to non-demineralized bone, effective adhesion was achieved on the surface-demineralized bone tissue. Shear adhesion strength was significantly higher in EDTA-treated samples (238.4 kPa at 10 h) compared to H3PO4-treated samples (102.9 kPa at 1 h), with performance correlating with demineralization depth. ATR-FTIR and SEM analyses revealed that EDTA preserved collagen's triple-helix structure and free water content, both enhancing adhesion. Animal experiments confirmed stable fixation of HAp adhesive to demineralized bone tissue.<br> Conclusions: Surface demineralization enabled strong adhesion of the solid-state HAp adhesive to bone by exposing collagen swollen with water. Adhesion strength was influenced by structural changes in the demineralized layer, and the adhesive provided stable in vivo fixation, supporting its potential for bone-anchored biomedical applications. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2772-5022 5 2 2025 Amelioration of Cd-induced bone deterioration by orally administered calcium phosphate 101482 EN Ping-chin Sung Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ahmad Bikharudin Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masahiro Okada Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Randa Musa Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kenta Uchida Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihisa Otaka Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tadaaki Matsusaka Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University Aira Matsugaki Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University Takayoshi Nakano Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University Takuya Matsumoto Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Cadmium (Cd) is a heavy metal that accumulates in the body, primarily through daily grain intake, and has a high affinity for bone, leading to skeletal diseases such as osteomalacia and fractures. Hydroxyapatite (HAp), a major bone mineral component, is highly pH-sensitive and is known to incorporate Cd, as observed in studies of Itai-itai disease. Based on these findings, we hypothesized that HAp could serve as an effective oral detoxification material for heavy metals. This study investigated the efficacy of orally administered HAp in inhibiting Cd-induced changes in bone physical and chemical properties, comparing its effects to those of activated charcoal (AC), a common detoxifying agent. Six-week-old male ICR mice were exposed to cadmium via drinking water containing CdCl2 and subsequently given diets containing either HAp or AC for four weeks. Three-point bending tests, micro-CT analysis, and histological observations of the femurs demonstrated that mice receiving HAp exhibited improved mechanical strength and enhanced bone quality protection compared to the control and other Cd-treated groups. Activated charcoal also contributed to bone quality improvement at low concentrations, but its effect diminished at high concentrations. These results suggest that the oral administration of HAp may be a promising therapeutic strategy for suppressing cadmium-induced osteomalacia. No potential conflict of interest relevant to this article was reported.

AIP Publishing Acta Medica Okayama 0021-9606 163 22 2025 Fourier-transform infrared spectroscopy of hydrogen fluoride dimers in solid parahydrogen 224312 EN Yuki Miyamoto Research Institute for Interdisciplinary Science, Okayama University Hiroki Ooe Graduate School of Natural Science and Technology, Okayama University Susumu Kuma Department of Physics, Rikkyo University We investigate the Fourier-transform infrared spectra of hydrogen fluoride dimers in solid parahydrogen, the detailed analysis of which has remained unexplored. We propose a plausible analysis based on concentration dependence, light polarization, annealing, and time evolution. The absorption lines exhibited multiple peaks, with intensity ratios significantly altered by annealing and by time evolution at a constant temperature. The spectral patterns and isotopic effects suggest that the dimers do not rotate freely in solid parahydrogen, while multiple peaks arise from different stable structures, including single and double substitution sites. Unlike in the gas phase and helium droplets, no tunneling splitting was observed. The broad ν1 band suggests that some dimer structures may exhibit axial rotation. Spectral changes due to annealing likely result from site conversion, while observed IR-induced changes indicate preferential dissociation of dimers in double substitution sites. These findings still remain tentative, necessitating further experimental and theoretical studies. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1523-7060 27 35 2025 Synthesis of a Pseudocytidine Nucleoside to Form a Stable and Selective Base Pair with Iso-guanosine in RNA 9749 9752 EN Ryo Miyahara Graduate School of Pharmaceutical Sciences, Kyushu University Yosuke Taniguchi Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Non-natural base pair formation provides insight into new functions of nucleic acids. Therefore, various artificial base pairs have been developed in both DNA and RNA. In this work, we successfully synthesized pseudocytidine from commercially available pseudouridine to form base pairs with isoguanine, also known as 2-OH-adenine, in RNA. Measurement of the melting temperature with the base pair incorporated at the center of a 13-mer RNA showed the highest value for the ψ-rC and iso-rG (2-OH-rA) base pair. This base pair formation exhibited a high melting temperature regardless of whether it was incorporated into the pyrimidine or purine strand, indicating that it can form a stable and selective duplex RNA. No potential conflict of interest relevant to this article was reported.

Pharmaceutical Society of Japan Acta Medica Okayama 0009-2363 73 5 2025 New Nucleoside Derivatives for Hybridization-Assisted Catalysis of Site-Selective Acetylation of 2′-OH of RNA 457 466 EN Hayate Takasaki Graduate School of Pharmaceutical Sciences, Kyushu University Kentaro Kitazaki Graduate School of Pharmaceutical Sciences, Kyushu University Yurie Hadano Graduate School of Pharmaceutical Sciences, Kyushu University Hirotaka Murase Faculty of Pharmaceutical Sciences, Sojo University Jeongsu Lee Graduate School of Pharmaceutical Sciences, Nagasaki International University Yosuke Taniguchi Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shigeki Sasaki Graduate School of Pharmaceutical Sciences, Kyushu University New nucleoside derivatives containing the imidazole (Imd), pyridine or pyrimidine catalytic group were designed for site-specific acetylation of 2′-OH of the RNA ribose moiety. When the RNA substrate was acetylated in the presence of acetic anhydride under alkaline conditions, Probe (Imd) containing the imidazole catalytic group acetylated with a high selectivity to the 2′-OH of the uridine opposite the catalytic nucleotide. Probe (Py-4N) containing the pyridine group showed a higher catalytic activity under neutral conditions with a high selectivity for the 2′-OH group of the 5′ side of the uridine opposite the catalytic nucleotide in about 80% modification yield within 10 min. This study has shown that the oligodeoxynucleotide incorporating the new nucleotide derivative with the catalytic group can be a useful tool for site-selective acetylation of RNA 2′-OH. No potential conflict of interest relevant to this article was reported.

Pharmaceutical Society of Japan Acta Medica Okayama 0009-2363 73 12 2025 Sequence-Selective 2′-O-Acetyl Modification of RNA Mediated by Duplex Formation with a Reactive Oligonucleotide Probe Incorporating 4-Thio-dT 1122 1125 EN Hirotaka Murase Faculty of Pharmaceutical Sciences, Sojo University Mio Eto Faculty of Pharmaceutical Sciences, Sojo University Jeongsu Lee Graduate School of Pharmaceutical Sciences, Nagasaki International University Yosuke Taniguchi Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shuhei Imoto Faculty of Pharmaceutical Sciences, Sojo University Shigeki Sasaki Graduate School of Pharmaceutical Sciences, Nagasaki International University We designed and synthesized an oligonucleotide acetylating reagent (Ac-probe) that selectively acetylates the 2′-OH groups of RNA upon forming a duplex with the target RNA. The Ac-probe can be readily prepared via a post-synthetic modification method using an oligodeoxynucleotide probe containing 4-thio-dT. During the acetylation reaction, 4-thio-dT is regenerated as the reaction proceeds. Notably, an efficient modification was observed when the complementary base of RNA to 4-thio-dT was cytosine or uracil, indicating the selectivity for the pyrimidine base. 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.

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.

Elsevier BV Acta Medica Okayama 2352-4855 90 2025 Species-specific sensitivity of marine phytoplankton to selected herbicides and antibiotics 104413 EN Shizuka Ohara Graduate School of Integrated Science for Life, Hiroshima University Toshimitsu Onduka Hatsukaichi Field Station, Fisheries Technology Institute, Japan Fisheries Research and Education Agency Shoko Ueki Institute of Plant Science and Resources, Okayama University Shotaro Naruse Graduate School of Integrated Science for Life, Hiroshima University Kazuhiko Koike Graduate School of Integrated Science for Life, Hiroshima University The toxicity of two herbicides (diuron and bromacil) and three antibiotics (clarithromycin, azithromycin, and clindamycin) was evaluated for on four marine phytoplankton species: two diatoms, Skeletonema costatum and Chaetoceros lorenzianus, a dinoflagellate, Prorocentrum shikokuense, and a raphidophyte, Heterosigma akashiwo. The 50 % effective concentrations (EC50-μ) for growth of the herbicides (approximately 2.3–24.3 μg L−1) were lower than those of the antibiotics, indicating their higher toxicity. The EC50-μ of diuron was close to its reported environmental concentrations. The EC50-μ values for the antibiotics substantially differed by species, ranging from 19.5 to > 1000 μg L−1, with diatoms showing higher sensitivity than flagellates. Herbicides inhibited the photosynthetic yield (φII) of all tested species at concentrations similar to or lower than those affecting growth, while antibiotics affected φII at higher concentrations. Under high-light conditions, photosynthesis in S. costatum was substantially inhibited by all chemicals except clindamycin, suggesting enhanced chemical toxicity under intense light. Overall, these findings indicate that these herbicides and antibiotics can alter phytoplankton abundance and composition in coastal areas and that environmental factors, such as increased solar radiation, can potentially enhance their toxicity. 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.

Acta Medica Okayama 2025 Development of a production method for biologically active globular proteins through chemical modification-based solubilization of denatured proteins EN Shuichiro KIMURA Graduate School of Natural Science and Technology, Okayama university No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0163-3864 2025 First Total Synthesis of the Kikai Island Polybrominated C3′–N1 Bisindole Alkaloid by a Directed Metalation Strategy 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 The first total synthesis of one out of four Kikai Island polybrominated C3′–N1 bisindole alkaloids from red alga Laurencia brongniartii is described. The key steps involve both dehydration of trans-hemiaminal and a C2′-methylthiolation of bisindole using dimethyl disulfide through directed metalation, followed by C3-methylthiolation using a N-SMe succinimide reagent. 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 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.

American Chemical Society (ACS) Acta Medica Okayama 0002-7863 2025 Optogenetic Cancer Therapy Using the Light-Driven Outward Proton Pump Rhodopsin Archaerhodopsin-3 (AR3) EN Shin Nakao Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Keiichi Kojima Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Keita Sato Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Naoya Kemmotsu Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hideyo Ohuchi Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yosuke Togashi Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuki Sudo Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Medicines used for cancer treatment often cause serious side effects by damaging normal cells due to nonspecific diffusion. To address this issue, we previously developed an optical method to induce apoptotic cell death via intracellular pH alkalinization using the outward proton pump rhodopsin, Archaerhodopsin-3 (AR3) in various noncancer model cells in vitro and in vivo. In this study, we applied this method to cancer cells and tumors to evaluate its potential as an anticancer therapeutic strategy. First, we confirmed that AR3-expressing murine cancer cell lines (MC38, B16F10) showed apoptotic cell death upon green light irradiation, as indicated by increased levels of cell death and apoptosis-related markers. Next, we established stable AR3-expressing MC38 and B16F10 cells by using viral vectors. When these AR3-expressing cells were subcutaneously transplanted into C57BL/6 mice, the resulting tumors initially grew at a rate comparable to that of control tumors lacking AR3 expression or light stimulation. However, upon green light irradiation, AR3-expressing tumors exhibited either a marked reduction in size or significantly suppressed growth, accompanied by the induction of apoptosis signals and decreased proliferation signals. These results demonstrate that AR3-mediated cell death has potent antitumor effects both in vitro and in vivo. This optical method thus holds promise as a novel cancer therapy with potentially reduced side effects. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0957-4522 36 1 2024 Optical bandgap tuning in SnO2–MoS2 nanocomposites: manipulating the mass of SnO2 and MoS2 using sonochemical solution mixing 6 EN Chinkhai Ong School of Engineering and Physical Sciences, Heriot-Watt University Malaysia Weng Nam Lee Heriot-Watt Global College, Heriot-Watt University Malaysia Yee Seng Tan Sunway Biofunctional Molecules Discovery Centre, School of Medical and Life Sciences, Sunway University Patrik Ohberg School of Engineering and Physical Sciences, Institute of Photonics and Quantum Sciences, Heriot-Watt University Yasuhiko Hayashi Faculty of Environmental, Life, Natural Science and Technology, Okayama University Takeshi Nishikawa Faculty of Environmental, Life, Natural Science and Technology, Okayama University Yuenkiat Yap Heriot-Watt Global College, Heriot-Watt University Malaysia This study investigates controlled optical bandgap tuning through precise adjustment of the SnO2 and MoS2 mass in nanocomposites. A sonochemical solution mixing method, coupled with bath sonication, is employed for the preparation of SnO2–MoS2 nanocomposite. This approach allows for comprehensive characterization using UV–Vis FTIR, XRD, EDX, Raman spectroscopies, and FESEM, providing insights into morphology, chemical, and optical properties. Increasing the SnO2 mass leads to a linear decrease in the optical bandgap energy, from 3.0 to 1.7 eV. Similarly, increasing the MoS2 mass also results in a decrease in the optical bandgap energy, with a limitation of around 2.01 eV. This work demonstrates superior control over optical bandgap by manipulating the SnO2 mass compared to MoS2, highlighting the complexities introduced by MoS2 2D nanosheets during sonication. These findings hold significant value for optoelectronic applications, emphasizing enhanced control of optical bandgap through systematic mass manipulation. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2694-2437 4 5 2024 New Catalytic Residues and Catalytic Mechanism of the RNase T1 Family 257 267 EN Katsuki Takebe Department of Dental Pharmacology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Mamoru Suzuki Institute for Protein Research, Osaka University Yumiko Hara Institute for Protein Research, Osaka University Takuya Katsutani Institute for Protein Research, Osaka University Naomi Motoyoshi School of Pharmacy, Nihon University Tadashi Itagaki School of Pharmacy, Nihon University Shuhei Miyakawa Graduate School of Pharmaceutical Sciences, Osaka University Kuniaki Okamoto Department of Dental Pharmacology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kaori Fukuzawa Graduate School of Pharmaceutical Sciences, Osaka University Hiroko Kobayashi School of Pharmacy, Nihon University The ribonuclease T1 family, including RNase Po1 secreted by Pleurotus ostreatus, exhibits antitumor activity. Here, we resolved the Po1/guanosine-3′-monophosphate complex (3′GMP) structure at 1.75 Å. Structure comparison and fragment molecular orbital (FMO) calculation between the apo form and the Po1/3′GMP complex identified Phe38, Phe40, and Glu42 as the key binding residues. Two types of the RNase/3′GMP complex in RNasePo1 and RNase T1 were homologous to Po1, and FMO calculations elucidated that the biprotonated histidine on the β3 sheet (His36) on the β3 sheet and deprotonated Glu54 on the β4 sheet were advantageous to RNase activity. Moreover, tyrosine (Tyr34) on the β3 sheet was elucidated as a crucial catalytic residues. Mutation of Tyr34 with phenylalanine decreased RNase activity and diminished antitumor efficacy compared to that in the wild type. This suggests the importance of RNase activity in antitumor mechanisms. 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.<br> 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.<br> 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.<br> 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.

American Geophysical Union (AGU) Acta Medica Okayama 2169-9313 130 1 2025 Reduced Thermal Conductivity of Hydrous Aluminous Silica and Calcium Ferrite‐Type Phase Promote Water Transportation to Earth's Deep Mantle e2024JB030704 EN Wen‐Pin Hsieh Institute of Earth Sciences, Academia Sinica Takayuki Ishii Institute for Planetary Materials, Okayama University Frédéric Deschamps Institute of Earth Sciences, Academia Sinica Yi‐Chi Tsao Institute of Earth Sciences, Academia Sinica Jen‐Wei Chang Institute of Earth Sciences, Academia Sinica Giacomo Criniti Earth and Planets Laboratory, Carnegie Institution for Science Subduction of oceanic slabs introduces chemical heterogeneities in the Earth's interior, which could further induce thermal, seismic, and geodynamical anomalies. Thermal conductivity of slab minerals crucially controls the thermal evolution and dynamics of the subducted slab and ambient mantle, while such an important transport property remains poorly constrained. Here we have precisely measured high pressure-temperature thermal conductivity of hydrous aluminous post-stishovite (ΛHy-Al-pSt) and aluminum-rich calcium ferrite-type phase (ΛCF), two important minerals in the subducted basaltic crust in the lower mantle. Compared to the dry aluminous stishovite and pure stishovite, hydration substantially reduces the ΛHy-Al-pSt, resulting in ∼9.7–13.3 W m−1 K−1 throughout the lower mantle. Surprisingly, the ΛCF remains at ∼3–3.8 W m−1 K−1 in the lower mantle, few-folds lower than previously assumed. Our data modeling offers better constraints on the thermal conductivity of the subducted oceanic crust from mantle transition zone to the lowermost mantle region, which is less thermally conductive than previously modeled. Our findings suggest that if the post-stishovite carries large amounts of water to the lower mantle, the poorer heat conduction through the basaltic crust reduces the slab's temperature, which not only allows the slab bringing more hydrous minerals to greater depth, but also increases slab's density and viscosity, potentially impacting the stability of heterogeneous structures at the lowermost mantle. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0008-6223 243 2025 Organic solvent transport through reduced graphene oxide membranes with controlled oxygen content 120539 EN Hongzhe Chen School of Materials Science and Engineering, University of New South Wales Sydney Tongxi Lin School of Materials Science and Engineering, University of New South Wales Sydney Zeno Rizqi Ramadhan Electron Microscope Unit, University of New South Wales Aditya Rawal Mark Wainwright Analytical Centre, University of New South Wales Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Amir Karton School of Science and Technology, University of New England Xiaojun Ren School of Materials Science and Engineering, University of New South Wales Sydney Rakesh Joshi School of Materials Science and Engineering, University of New South Wales Sydney Recent advances in membranes based on 2-dimensional (2D) materials have enabled precise control over angstrom-scale pores, providing a unique platform for studying diverse mass transport mechanisms. In this work, we systematically investigate the transport of solvent vapors through 2D channels made of graphene oxide (GO) laminates with precisely controlled oxygen content. Using in-situ chemical reduction of GO with vitamin C, we fabricated reduced GO membranes (VRGMs) with oxygen content systematically decreased from 31.6 % (pristine GO) to 24.0 % (VRGM-maximum reduction). Vapor permeability measurements showed a distinct correlation between oxygen functional groups and solvent transport behaviour. Specifically, non-polar hexane exhibits 114 % of enhanced permeance through the reduced membranes with larger graphitic domains, while the permeance of water decreases by 55 %. With the support of density functional theory (DFT) simulations, we modelled the hydrogen-bond and dispersion complexes between the solvents and GO and calculated the complexation energies. The simulation results suggest that polar molecules interact with the oxygen functional groups of GO via a hydrogen-bond network, supporting in-plane transport. In contrast, van der Waals forces drive the transport of low-polarity solvents along the graphitic domains of the 2D channel in reduced GO membranes. Our findings provide potential strategies for future design of organic solvent nanofiltration membranes. No potential conflict of interest relevant to this article was reported.

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.

Elsevier BV Acta Medica Okayama 2590-1974 27 2025 Development of a technique to identify μm-sized organic matter in asteroidal material: An approach using machine learning 100277 EN Rahul Kumar The Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Katsura Kobayashi The Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Christian Potiszil The Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Tak Kunihiro The Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Asteroidal materials contain organic matter (OM), which records a number of extraterrestrial environments and thus provides a record of Solar System processes. OM contain essential compounds for the origin of life. To understand the origin and evolution of OM, systematic identification and detailed observation using in-situ techniques is required. While both nm- and μm-sized OM were studied previously, only a small portion of a given sample surface was investigated in each study. Here, a novel workflow was developed and applied to identify and classify μm-sized OM on mm-sized asteroidal materials. The workflow involved image processing and machine learning, enabling a comprehensive and non-biased way of identifying, classifying, and measuring the properties of OM. We found that identifying OM is more accurate by classification with machine learning than by clustering. On the approach of classification with machine learning, five algorithms were tested. The random forest algorithm was selected as it scored the highest in 4 out of 5 accuracy parameters during evaluation. The workflow gave modal OM abundances that were consistent with those identified manually, demonstrating that the workflow can accurately identify 1-15 μm-sized OM. The size distribution of OM was modeled using the power-law distribution, giving slope α values that were consistent with fragmentation processes. The shape of the OM was quantified using circularity and solidity, giving a positive correlation and indicating these properties are closely related. Overall, the workflow enabled identification of many OM quickly and accurately and the obtainment of chemical and petrographic information. Such information can help the selection of OM for further in-situ techniques, and elucidate the origin and evolution of OM preserved in asteroidal materials. 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.

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.

Springer Science and Business Media LLC Acta Medica Okayama 0947-8396 131 9 2025 Optical and chemical properties of silver tree-like structure treated with gold galvanic substitution 744 EN Kazushi Honda Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Nobuyuki Takeyasu Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Galvanic gold substitution was executed in the presence of trisodium citrate on silver tree-like structures. No discernible difference in geometry was observed between the pre- and post-gold substitution phases, which benefited from the presence of citrate ions. The extent of gold substitution was regulated by the amount of gold ion solution added. After the gold substitution, an increase in extinction was observed in the ultraviolet region, indicating that gold was deposited at the surface. Raman scattering of para-toluenethiol was measured on the gold/silver tree-like structures at 488 nm excitations, where a decrease in the Raman peak intensity was observed as the quantity of gold ion solution increased. The results indicated that the optical property of silver was lost due to the increase of the amount of gold deposition. Concurrently, an investigation was conducted into the chemical resistance of the gold/silver tree-like structures, which was evaluated by measuring the resistivity inverse-proportional to the amount of silver ions dissolved by the diluted nitric acid. As the amount of gold ion solution added increased, the resistivity increased and became constant. The result implied that the surface chemical property had undergone a complete transformation into gold. 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 2673-4087 6 2 2025 An Endocrine-Disrupting Chemical, Bisphenol A Diglycidyl Ether (BADGE), Accelerates Neuritogenesis and Outgrowth of Cortical Neurons via the G-Protein-Coupled Estrogen Receptor 53 EN Ikuko Miyazaki Department of Medical Neurobiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Chiharu Nishiyama Department of Medical Neurobiology, Okayama University Medical School Takeru Nagoshi Department of Medical Neurobiology, Okayama University Medical School Akane Miyako Department of Medical Neurobiology, Okayama University Medical School Suzuka Ono Department of Medical Neurobiology, Okayama University Medical School Ichika Misawa Department of Medical Neurobiology, Okayama University Medical School Aika Isse Department of Medical Neurobiology, Okayama University Medical School Kana Tomimoto Department of Medical Neurobiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kaori Masai Department of Medical Neurobiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazumasa Zensho Department of Medical Neurobiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masato Asanuma Department of Medical Neurobiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Bisphenol A diglycidyl ether (BADGE) is the main component of epoxy resin and is used for the inner coating of canned foods and plastic food containers. BADGE can easily migrate from containers and result in food contamination; the compound is known as an endocrine-disrupting chemical. We previously reported that maternal exposure to bisphenol A bis (2,3-dihydroxypropyl) ether (BADGE·2H2O), which is the most detected BADGE derivative not only in canned foods but also in human specimens, during gestation and lactation, could accelerate neuronal differentiation in the cortex of fetuses and induce anxiety-like behavior in juvenile mice. In this study, we investigated the effects of low-dose BADGE·2H2O (1–100 pM) treatment on neurites and the mechanism of neurite outgrowth in cortical neurons. BADGE·2H2O exposure significantly increased the number of dendrites and neurite length in cortical neurons; these accelerating effects were inhibited by estrogen receptor (ER) antagonist ICI 182,780 and G-protein-coupled estrogen receptor (GPER) antagonist G15. BADGE·2H2O down-regulated Hes1 expression, which is a transcriptional repressor, and increased levels of neuritogenic factor neurogenin-3 (Ngn3) in the cortical neurons; the changes were significantly blocked by G15. These data suggest that direct BADGE·2H2O exposure can accelerate neuritogenesis and outgrowth in cortical neurons through down-regulation of Hes1 and by increasing Ngn3 levels through ERs, particularly GPER. 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.

American Chemical Society (ACS) Acta Medica Okayama 2637-6105 2025 Tailoring Mechanical Properties and Ionic Conductivity of Poly(ionic liquid)-Based Ion Gels by Tuning Anion Compositions 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.

American Chemical Society (ACS) Acta Medica Okayama 1554-8929 19 12 2024 Discovery of a Compound That Inhibits IRE1α S-Nitrosylation and Preserves the Endoplasmic Reticulum Stress Response under Nitrosative Stress 2429 2437 EN Haruna Kurogi Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Nobumasa Takasugi Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Sho Kubota Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ashutosh Kumar Laboratory for Structural Bioinformatics, Center for Biosystems Dynamics Research, RIKEN Takehiro Suzuki Biomolecular Characterization Unit, Technology Platform Division, RIKEN Center for Sustainable Resource Science Naoshi Dohmae Biomolecular Characterization Unit, Technology Platform Division, RIKEN Center for Sustainable Resource Science Daisuke Sawada Department of Fine Organic Synthesis, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kam Y.J. Zhang Laboratory for Structural Bioinformatics, Center for Biosystems Dynamics Research, RIKEN Takashi Uehara Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Inositol-requiring enzyme 1α (IRE1α) is a sensor of endoplasmic reticulum (ER) stress and drives ER stress response pathways. Activated IRE1α exhibits RNase activity and cleaves mRNA encoding X-box binding protein 1, a transcription factor that induces the expression of genes that maintain ER proteostasis for cell survival. Previously, we showed that IRE1α undergoes S-nitrosylation, a post-translational modification induced by nitric oxide (NO), resulting in reduced RNase activity. Therefore, S-nitrosylation of IRE1α compromises the response to ER stress, making cells more vulnerable. We conducted virtual screening and cell-based validation experiments to identify compounds that inhibit the S-nitrosylation of IRE1α by targeting nitrosylated cysteine residues. We ultimately identified a compound (1ACTA) that selectively inhibits the S-nitrosylation of IRE1α and prevents the NO-induced reduction of RNase activity. Furthermore, 1ACTA reduces the rate of NO-induced cell death. Our research identified S-nitrosylation as a novel target for drug development for IRE1α and provides a suitable screening strategy. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-7345 2025 Revisiting 3-azidoindoles: overcoming the trade-off challenges between stability and reactivity of in situ-generated azidoindoles 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.

American Chemical Society (ACS) Acta Medica Okayama 2575-9108 7 9 2024 Rethinking Thin-Layer Chromatography for Screening Technetium-99m Radiolabeled Polymer Nanoparticles 2604 2611 EN Kathrin Schorr Department of Pharmaceutical Technology, University of Regensburg Xinyu Chen Nuclear Medicine, Faculty of Medicine, University of Augsburg Takanori Sasaki Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Anahi Paula Arias-Loza Department of Nuclear Medicine and Comprehensive Heart Failure Center, University Hospital Würzburg Johannes Lang Department of Pharmaceutical Technology, University of Regensburg Takahiro Higuchi Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Achim Goepferich Department of Pharmaceutical Technology, University of Regensburg Thin-layer chromatography (TLC) is commonly employed to screen technetium-99m labeled polymer nanoparticle batches for unreduced pertechnetate and radio-colloidal impurities. Although this method is widely accepted, our findings applying radiolabeled PLGA/PLA–PEG nanoparticles underscore its lack of transferability between different settings and its limitations as a standalone quality control tool. While TLC profiles may appear similar for purified and radiocolloid containing nanoparticle formulations, their in vivo behavior can vary significantly, as demonstrated by discrepancies between TLC results and single-photon emission computed tomography (SPECT) and biodistribution data. This highlights the urgent need for a case-by-case evaluation of TLC methods for each specific nanoparticle type. Our study revealed that polymeric nanoparticles cannot be considered analytically uniform entities in the context of TLC analysis, emphasizing the complex interplay between nanoparticle composition, radiolabeling conditions, and subsequent biological behavior. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 0032-5791 104 3 2025 An ultra-simplified protocol for PCR template preparation from both unsporulated and sporulated Eimeria oocysts 104810 EN Aruto Takano Departments of Veterinary Immunology, Graduate School of Veterinary Medical Sciences, Osaka Metropolitan University Dennis V. Umali Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of the Philippines Los Baños, College April H. Wardhana Research Center for Veterinary Science, National Research and Innovation Agency Dyah H. Sawitri Research Center for Veterinary Science, National Research and Innovation Agency Isao Teramoto Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University Toshimitsu Hatabu Laboratory of Animal Physiology, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yasutoshi Kido Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University Akira Kaneko Departments of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University Kazumi Sasai Departments of Veterinary Immunology, Graduate School of Veterinary Medical Sciences, Osaka Metropolitan University Hiromitsu Katoh Departments of Veterinary Immunology, Graduate School of Veterinary Medical Sciences, Osaka Metropolitan University Makoto Matsubayashi Departments of Veterinary Immunology, Graduate School of Veterinary Medical Sciences, Osaka Metropolitan University Molecular biological techniques have enabled the accurate identification of the avian Eimeria parasite, however, the preparation of PCR template remains a bottleneck due to contaminants from feces and the robust oocyst's wall resistant to chemical and mechanical force. Generally, the preparation of PCR template involves three main steps: (1) pretreatment of oocysts; (2) disruption of oocysts; and (3) purification of genomic DNA. We prepared PCR templates from both unsporulated and sporulated E. tenella oocysts using various protocols, followed by species-specific PCR to define the limit of detection. Our data revealed that whereas neither pretreatment of oocysts with sodium hypochlorite nor purification of genomic DNA with commercial kits improved the limit of detection of PCR, disruption of oocysts was a critical step in the preparation of PCR templates. The most sensitive PCR assay was achieved with the template prepared by disrupting oocysts suspended in distilled water, followed by bead-beating and heating at 99°C for 5 min, which detected 0.16 oocysts per PCR. This ultra-simplified protocol for preparation of PCR template, which does not require expensive reagents or equipment, will significantly enhance the sensitive and efficient molecular identification of Eimeria. It will improve our understanding of the prevalence of this parasite at the species level and contribute to the development of techniques for the control in the field. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2694-2496 4 4 2024 Light-Responsive and Antibacterial Graphenic Materials as a Holistic Approach to Tissue Engineering 263 272 EN Andrea Ferreras Department of Bioengineering, Universidad Carlos III de Madrid Ana Matesanz Department of Electronic Technology, Universidad Carlos III de Madrid Jabier Mendizabal Domotek ingeniería prototipado y formación S.L. Koldo Artola Domotek ingeniería prototipado y formación S.L. Yuta Nishina Graduate School of Natural Science and Technology, Okayama University Pablo Acedo Department of Electronic Technology, Universidad Carlos III de Madrid José L. Jorcano Department of Bioengineering, Universidad Carlos III de Madrid Amalia Ruiz Institute of Cancer Therapeutics, School of Pharmacy and Medical Sciences, Faculty of Life Sciences, University of Bradford Giacomo Reina Empa Swiss Federal Laboratories for Materials Science and Technology Cristina Martín Department of Bioengineering, Universidad Carlos III de Madrid While the continuous development of advanced bioprinting technologies is under fervent study, enhancing the regenerative potential of hydrogel-based constructs using external stimuli for wound dressing has yet to be tackled. Fibroblasts play a significant role in wound healing and tissue implants at different stages, including extracellular matrix production, collagen synthesis, and wound and tissue remodeling. This study explores the synergistic interplay between photothermal activity and nanomaterial-mediated cell proliferation. The use of different graphene-based materials (GBM) in the development of photoactive bioinks is investigated. In particular, we report the creation of a skin-inspired dressing for wound healing and regenerative medicine. Three distinct GBM, namely, graphene oxide (GO), reduced graphene oxide (rGO), and graphene platelets (GP), were rigorously characterized, and their photothermal capabilities were elucidated. Our investigations revealed that rGO exhibited the highest photothermal efficiency and antibacterial properties when irradiated, even at a concentration as low as 0.05 mg/mL, without compromising human fibroblast viability. Alginate-based bioinks alongside human fibroblasts were employed for the bioprinting with rGO. The scaffold did not affect the survival of fibroblasts for 3 days after bioprinting, as cell viability was not affected. Remarkably, the inclusion of rGO did not compromise the printability of the hydrogel, ensuring the successful fabrication of complex constructs. Furthermore, the presence of rGO in the final scaffold continued to provide the benefits of photothermal antimicrobial therapy without detrimentally affecting fibroblast growth. This outcome underscores the potential of rGO-enhanced hydrogels in tissue engineering and regenerative medicine applications. Our findings hold promise for developing game-changer strategies in 4D bioprinting to create smart and functional tissue constructs with high fibroblast proliferation and promising therapeutic capabilities in drug delivery and bactericidal skin-inspired dressings. 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.

African Journals Online (AJOL) Acta Medica Okayama 1726-801X 39 8 2025 Chemical composition of essential oil of Acacia crassicarpa Benth. (Fabaceae) from Vietnam 1653 1660 EN Tuan Quoc Doan Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Tai Tien Dinh Hue Union of Science and Technology Associations (HUSTA) Tetsuya K. Matsumoto Graduate School of Science and Engineering, Ibaraki University Dien Dinh Phong Dien Nature Reserve, Phong Dien district, Thua Thien Hue province Naoko Miki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Muneto Hirobe Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Hoai Thi Nguyen Faculty of Pharmacy, Hue University of Medicine and Pharmacy, Hue University This research aimed to identify the volatile compounds found in the fresh leaves of Acacia crassicarpa Benth. This is the first phytochemical investigation of this species. Essential oils from the leaves of A. crassicarpa were obtained by hydro-distillation and analyzed by gas chromatography coupled with mass spectrometry (GC/MS). Sixty-one compounds accounting for 95.8% of the leaf oil were identified. The classes of compounds identified in the oil sample were aldehydes (30.7%), sesquiterpene hydrocarbons (25.2%), alkanes (19.1%), oxygenated monoterpenes (3.6%) oxygenated sesquiterpenes (2.3%), monoterpene hydrocarbons (0.8%) and others (14.2%). The major constituents in the leaf oil were tridecanal (24.5%), (E)-caryophyllene (11.7%), n-heneicosane (7.2%), squalene (6.5%), and 7-tetradecenal (5.9%). No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 2574-0962 8 13 2025 Microagglomerate of VO2 Particles Packing Paraffin Wax Using Capillary Force as a Latent Thermal Energy Storage Medium 9595 9603 EN Kazuma Isobe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Kaketo Yamauchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yutaka Yamada Faculty of Environmental, Life, Natural Science and Technology, Okayama University Akihiko Horibe Faculty of Environmental, Life, Natural Science and Technology, Okayama University This study proposed a material to retain paraffin wax with vanadium dioxide (VO2) particles as a latent thermal energy storage medium, an alternative to core–shell microcapsules containing phase change materials. VO2 microparticles, which were synthesized through a sol–gel method and annealing process, were dispersed in the oil-in-water microemulsion to obtain microagglomerates of VO2 microparticles. The average diameter of microagglomerates was 5 μm, and they retained paraffin wax at the vacancies among VO2 particles. Although the microagglomerates had no complete shells similar to core–shell microcapsules, the microagglomerates successfully trapped paraffin wax droplets without any leakage even in a high-temperature environment. It was because capillary forces acting among VO2 particles strictly prevented any leakage of paraffin waxes. The differential scanning calorimetry revealed that the microagglomerates contained only 16.5 wt % of n-octadecane, used as a paraffin wax. However, since VO2 particles can release or absorb latent heat due to their metal–insulator phase transition, the proposed microagglomerates exhibited higher thermal energy storage densities than phase change microcapsules whose shells do not show phase transitions. Moreover, the microagglomerates exhibited higher thermal conductivity than microcapsules with amorphous inorganic shells because the VO2 particles were crystallized through annealing. The proposed microagglomerate is a promising form for further improving the thermal energy storage density and thermal performance of the latent thermal energy storage medium, especially in the temperature range of 30 to 70 °C. 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.

Springer Science and Business Media LLC Acta Medica Okayama 0910-6340 41 7 2025 Direct insertion of an ion channel immobilized on a soft agarose gel bead into a lipid bilayer: an optimized method 1073 1082 EN Mami Asakura Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Shuyan Wang Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Minako Hirano Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Toru Ide Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University In this paper, we report the development of a device that improves the conventional artificial lipid bilayer method and can measure channel currents more efficiently. Ion channel proteins are an attractive research target in biophysics, because their functions can be measured at the single-molecule level with high time resolution. In addition, they have attracted attention as targets for drug discovery because of their crucial roles in vivo. Although electrophysiological methods are powerful tools for studying channel proteins, they suffer from low measurement efficiency and require considerable skill. In our previous paper, we reported that by immobilizing channel proteins on agarose gel beads and forming an artificial lipid bilayer on the bead surface, we simultaneously solved two problems that had been hindering the efficiency of the artificial bilayer method: the time-consuming formation of artificial lipid bilayers and the time-consuming incorporation of channels into artificial bilayers. Previous studies have utilized crosslinked hard beads; however, here we show that channel current measurement can be achieved more simply and efficiently using non-crosslinked soft beads. In this study, we detailed the process of immobilizing channel proteins on the surface of non-crosslinked beads through chemical modification, allowing us to measure their channel activity. This method enables current measurements without the need for stringent bead size selection or high negative pressure. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0910-6340 41 4 2024 Efficient single-channel current measurements of the human BK channel using a liposome-immobilized gold probe 329 334 EN Minako Hirano Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mami Asakura Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Toru Ide Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University The human BK channel (hBK) is an essential membrane protein that regulates various biological functions, and its dysfunction leads to serious diseases. Understanding the biophysical properties of hBK channels is crucial for drug development. Artificial lipid bilayer recording is used to measure biophysical properties at the single-channel level. However, this technique is time-consuming and complicated; thus, its measurement efficiency is very low. Previously, we developed a novel technique to improve the measurement efficiency by rapidly forming lipid bilayer membranes and incorporating ion channels into the membrane using a hydrophilically modified gold probe. To further improve our technique for application to the hBK channel, we combined it using the gold probe with a liposome fusion method. Using a probe on which liposomes containing hBK channels were immobilized, the channels were efficiently incorporated into the lipid bilayer membrane, and the measured channel currents showed the current characteristics of the hBK channel. This technique will be useful for the efficient measurements of the channel properties of hBK and other biologically important channels. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2076-3921 14 7 2025 Carnosol, a Rosemary Ingredient Discovered in a Screen for Inhibitors of SARM1-NAD+ Cleavage Activity, Ameliorates Symptoms of Peripheral Neuropathy 808 EN Hitoshi Murata Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuki Ogawa Tama Biochemical Co., Ltd. Yu Yasui Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiki Ochi Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Nahoko Tomonobu Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Ken-Ichi Yamamoto Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Rie Kinoshita Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yoji Wada Tama Biochemical Co., Ltd. Hiromichi Nakamura Tama Biochemical Co., Ltd. Masahiro Nishibori Department of Translational Research and Drug Development, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masakiyo Sakaguchi Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Sterile alpha and Toll/interleukin receptor motif-containing protein 1 (SARM1) is a nicotinamide adenine dinucleotide (NAD+) hydrolase involved in axonal degeneration and neuronal cell death. SARM1 plays a pivotal role in triggering the neurodegenerative processes that underlie peripheral neuropathies, traumatic brain injury, and neurodegenerative diseases. Importantly, SARM1 knockdown or knockout prevents the degeneration; as a result, SARM1 has been attracting attention as a potent therapeutic target. In recent years, the development of several SARM1 inhibitors derived from synthetic chemical compounds has been reported; however, no dietary ingredients with SARM1 inhibitory activity have been identified. Therefore, we here focused on dietary ingredients and found that carnosol, an antioxidant contained in rosemary, inhibits the NAD+-cleavage activity of SARM1. Purified carnosol inhibited the enzymatic activity of SARM1 and suppressed neurite degeneration and cell death induced by the anti-cancer medicine vincristine (VCR). Carnosol also inhibited VCR-induced hyperalgesia symptoms, suppressed the loss of intra-epidermal nerve fibers in vivo, and reduced the blood fluid level of phosphorylated neurofilament-H caused by an axonal degeneration event. These results indicate that carnosol has a neuroprotective effect via SARM1 inhibition in addition to its previously known antioxidant effect via NF-E2-related factor 2 and thus suppresses neurotoxin-induced peripheral neuropathy. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1433-7851 2025 Development of a Vinylated Cyclic Allene: A Fleeting Strained Diene for the Diels–Alder Reaction e202510319 EN Haruki Mizoguchi Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Takumi Obata Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Taiki Hirai Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Manaka Komatsu Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Akira Sakakura Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Fleeting molecules possessing strained multiple bonds are important components in organic synthesis due to their ability to undergo various chemical reactions driven by the release of strain energy. Although the use of strained π-bonds as 2π components, represented by dienophiles in Diels–Alder reactions, has been well studied, “the strained diene (4π component) approach” for molecular construction remains underexplored. Herein, we report the design of a vinyl cyclic allene (1-vinyl-1,2-cyclohexadiene) as a highly reactive strained diene and the development of its Diels–Alder reactions. Experimental and computational studies of vinyl cyclic allenes revealed that this diene system undergoes cycloaddition with dienophiles regio- and stereoselectively under mild reaction conditions. These studies also provide insight into the reactivity and selectivity of the system. The strained diene approach enables the convergent construction of polycyclic molecules through bond disconnections distinct from conventional retrosynthetic analysis, thus offering an efficient strategy for the assembly of functional molecules. 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.

American Chemical Society (ACS) Acta Medica Okayama 1523-7060 2025 Transformation of α,β-Unsaturated Aldehydes with a Small Amount of Electricity: Cyanosilylation, Isomerization, and Nucleophilic Addition 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.

Okayama University Medical School Acta Medica Okayama 0386-300X 79 3 2025 A Case of Aniline Poisoning Manifesting as Cyanosis with Unknown Cause 209 212 EN Kenichi Taguchi Department of Gastroenterology, NHO Iwakuni Clinical Center Kazuya Nishii Department of Respiratory Medicine, NHO Iwakuni Clinical Center Sakura Hata Department of Gastroenterology, NHO Iwakuni Clinical Center Shoichi Kuyama Shoichi Tanaka Department of Gastroenterology, NHO Iwakuni Clinical Center Case Report 10.18926/AMO/68729 A 38-year-old man was brought to the hospital for emergency treatment of cyanosis. The patient exhibited generalized cyanosis and impaired consciousness despite adequate oxygen therapy. Arterial blood was black, and arterial blood gas analysis revealed an abnormally high methemoglobin level of 67.8%. We later interviewed his colleagues regarding his exposure to aniline while working at the factory and diagnosed him with methemoglobinemia due to aniline poisoning. The patient was administered methylene blue (MB) after being transferred to another hospital, where this treatment was available, resulting in an improvement in symptoms. Although rare, methemoglobinemia is serious. A good understanding of the circumstances at disease onset, characteristic findings, and abnormal values of methemoglobinemia is important. In addition, MB is an important therapeutic for the treatment of methemoglobinemia; if MB is not available at a particular hospital, transfer of the patient to a hospital that stocks MB should be considered. 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.

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.

American Chemical Society (ACS) Acta Medica Okayama 0743-7463 41 11 2025 Droplet Impact Behavior on Convex Surfaces with a Circumferential Wettability Difference 7640 7647 EN Taku Ishikawa Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yutaka Yamada Faculty of Environmental, Life, Natural Science and Technology, Okayama University Kazuma Isobe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Akihiko Horibe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Controlling the bouncing behavior of the impacting droplets is an important issue for splay cooling, icing prevention, and other applications. The bouncing behavior of impacting droplets on superhydrophobic curved surfaces and flat substrates with a wettability difference has been widely investigated, and droplets impacting these surfaces show shorter contact times than those on superhydrophobic flat surfaces and droplet transport. However, there have been few studies on the droplet impact behavior on curved surfaces with a wettability difference, where efficient droplet control could be achieved by combining the features. In the present study, droplet impact experiments were conducted using copper cylinders with different circumferential wettabilities from hydrophilic to superhydrophobic, varying the impact velocity, cylinder diameter, and rotation angle. Droplets that impacted the wettability boundary showed asymmetric deformation and moved to the hydrophilic side, owing to the driving force of the wettability difference. Moreover, the droplet behavior was classified into four types: the droplet bounced off the surface, the droplet bounced off the surface and split, the droplet attached to the surface, and the droplet attached to the surface and split. The droplet behavior was estimated by using the maximum spreading width of the droplet impacted on the flat substrate. We evaluated whether the droplets attached to the surface or bounced off the surface after impact using the Weber number and rotation angle, and the estimations were in agreement with the experimental results for cylinder diameters of 4 and 6 mm. 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.

MDPI Acta Medica Okayama 2224-2708 14 1 2024 Enhancing Campus Environment: Real-Time Air Quality Monitoring Through IoT and Web Technologies 2 EN Alfiandi Aulia Rahmadani Department of Electrical Engineering, State Polytechnic of Malang Yan Watequlis Syaifudin Department of Information Technology, State Polytechnic of Malang Budhy Setiawan Department of Electrical Engineering, State Polytechnic of Malang Yohanes Yohanie Fridelin Panduman Department of Information and Communication Systems, Okayama University Nobuo Funabiki Department of Information and Communication Systems, Okayama University Nowadays, enhancing campus environments through mitigations of air pollutions is an essential endeavor to support academic achievements, health, and safety of students and staffs in higher educational institutes. In laboratories, pollutants from welding, auto repairs, or chemical experiments can drastically degrade the air quality in the campus, endangering the respiratory and cognitive health of students and staffs. Besides, in universities in Indonesia, automobile emissions of harmful substances such as carbon monoxide (CO), nitrogen dioxide (NO2), and hydrocarbon (HC) have been a serious problem for a long time. Almost everybody is using a motorbike or a car every day in daily life, while the number of students is continuously increasing. However, people in many campuses including managements do not be aware these problems, since air quality is not monitored. In this paper, we present a real-time air quality monitoring system utilizing Internet of Things (IoT) integrated sensors capable of detecting pollutants and measuring environmental conditions to visualize them. By transmitting data to the SEMAR IoT application server platform via an ESP32 microcontroller, this system provides instant alerts through a web application and Telegram notifications when pollutant levels exceed safe thresholds. For evaluations of the proposed system, we adopted three sensors to measure the levels of CO, NO2, and HC and conducted experiments in three sites, namely, Mechatronics Laboratory, Power and Emission Laboratory, and Parking Lot, at the State Polytechnic of Malang, Indonesia. Then, the results reveal Good, Unhealthy, and Dangerous for them, respectively, among the five categories defined by the Indonesian government. The system highlighted its ability to monitor air quality fluctuations, trigger warnings of hazardous conditions, and inform the campus community. The correlation of the sensor levels can identify the relationship of each pollutant, which provides insight into the characteristics of pollutants in a particular scenario. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0278-6915 197 2025 Fraglide-1 from traditional Chinese aromatic vinegar: A natural AhR antagonist for atopic dermatitis 115301 EN Kosuke Kato Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Miki Akamatsu Graduate School of Environmental and Life Science, 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 Masahiro Takagi School of Materials Science, Japan Advanced Institute of Science and Technology Masahiro Miyashita Graduate School of Agriculture, Kyoto University Yoshiyuki Murata Graduate School of Environmental and Life Science, Okayama University Yoshimasa Nakamura Graduate School of Environmental and Life Science, Okayama University Ayano Satoh Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Yoshio Tsujino Graduate School of Science, Technology and Innovation, Kobe University Traditional Chinese Zhenjiang aromatic vinegar (Kozu) contains Fraglide-1 (FG1), a bioactive lactone with demonstrated peroxisome proliferator-activated receptor gamma (PPARγ) agonist and antioxidant activities. This study explored FG1's novel ability to antagonize the aryl hydrocarbon receptor (AhR) signaling pathway, which regulates artemin expression and contributes to itching and inflammation in atopic dermatitis. Through molecular docking simulations and cell-based assays in human keratinocytes, we demonstrated FG1's potent antagonistic activity against AhR signaling. FG1 effectively suppressed FICZ-induced inflammatory responses, including artemin expression, with potency (half maximal inhibitory concentration, IC50 = 5.1 μM) comparable to the synthetic antagonist StemRegenin 1 (SR1) while demonstrating a superior safety profile (median lethal concentration, LC50 > 100 μM vs. 27.5 μM for SR1). These findings expand our understanding of bioactive compounds from traditional fermented foods and their regulatory effects on AhR signaling, providing a foundation for future studies on FG1's role in modulating skin inflammation. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0361-8609 96 10 2021 Validated international definition of the thrombocytopenia, anasarca, fever, reticulin fibrosis, renal insufficiency, and organomegaly clinical subtype (TAFRO) of idiopathic multicentric Castleman disease 1241 1252 EN Yoshito Nishimura Department of General Medicine, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences David C. Fajgenbaum Center for Cytokine Storm Treatment & Laboratory, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania Sheila K. Pierson Center for Cytokine Storm Treatment & Laboratory, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania Noriko Iwaki Hematology/Respiratory Medicine, Kanazawa University Graduate School of Medical Science Asami Nishikori Division of Pathophysiology, Okayama University Graduate School of Health Sciences Mitsuhiro Kawano Department of Rheumatology, Kanazawa University Graduate School of Medical Science Naoya Nakamura Department of Pathology, Tokai University School of Medicine Koji Izutsu Department of Hematology, National Cancer Center Hospital Kengo Takeuchi Department of Pathology, The Cancer Institute Hospital of Japanese Foundation for Cancer Research Midori Filiz Nishimura Department of Pathology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Yoshinobu Maeda Department of Hematology, Oncology and Respiratory Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Fumio Otsuka Department of General Medicine, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Kazuyuki Yoshizaki Department of Organic Fine Chemicals, Institute of Scientific and Industrial Research, Osaka University Eric Oksenhendler Department of Clinical Immunology, Hôpital Saint-Louis Frits van Rhee Myeloma Center, University of Arkansas for Medical Sciences Yasuharu Sato Division of Pathophysiology, Okayama University Graduate School of Health Sciences Thrombocytopenia, anasarca, fever, reticulin fibrosis, renal insufficiency, and organomegaly (TAFRO) syndrome is a heterogeneous entity manifesting with a constellation of symptoms described above that can occur in the context of idiopathic multicentric Castleman disease (iMCD) as well as infectious diseases, malignancies, and rheumatologic disorders. So, iMCD-TAFRO is an aggressive subtype of iMCD with TAFRO syndrome and often hyper-vascularized lymph nodes. Since we proposed diagnostic criteria of iMCD-TAFRO in 2016, we have accumulated new insights on the disorder and additional cases have been reported worldwide. In this systematic review and cohort analysis, we established and validated a definition for iMCD-TAFRO. First, we searched PubMed and Japan Medical Abstracts Society databases using the keyword “TAFRO” to extract cases. Patients with possible systemic autoimmune diseases and hematologic malignancies were excluded. Our search identified 54 cases from 50 articles. We classified cases into three categories: (1) iMCD-TAFRO (TAFRO syndrome with lymph node histopathology consistent with iMCD), (2) possible iMCD-TAFRO (TAFRO syndrome with no lymph node biopsy performed and no other co-morbidities), and (3) TAFRO without iMCD or other co-morbidities (TAFRO syndrome with lymph node histopathology not consistent with iMCD or other comorbidities). Based on the findings, we propose an international definition requiring four clinical criteria (thrombocytopenia, anasarca, fever/hyperinflammatory status, organomegaly), renal dysfunction or characteristic bone marrow findings, and lymph node features consistent with iMCD. The definition was validated with an external cohort (the ACCELERATE Natural History Registry). The present international definition will facilitate a more precise and comprehensive approach to the diagnosis of iMCD-TAFRO. 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.

MDPI Acta Medica Okayama 2079-6374 15 1 2025 Mapping Surface Potential in DNA Aptamer-Neurochemical and Membrane-Ion Interactions on the SOS Substrate Using Terahertz Microscopy 46 EN Kosei Morita Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Yuta Mitsuda Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Sota Yoshida 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 Jin Wang Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University In this study, we utilized a terahertz chemical microscope (TCM) to map surface potential changes induced by molecular interactions on silicon-on-sapphire (SOS) substrates. By functionalizing the SOS substrate with DNA aptamers and an ion-selective membrane, we successfully detected and visualized aptamer-neurochemical complexes through the terahertz amplitude. Additionally, comparative studies of DNA aptamers in PBS buffer and artificial cerebrospinal fluid (aCSF) were performed by computational structure modeling and terahertz measurements. Beyond neurochemicals, we also investigated calcium ions, measuring their concentrations in PDMS-fabricated micro-wells using minimal sample volumes. Our results highlight the capability of TCM as a powerful, label-free, and sensitive platform for the probing and mapping of surface potential arising from molecular interactions, with broad implications for biomedical diagnostics and research. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0008-6223 234 2025 Reversible chemical modifications of graphene oxide for enhanced viral capture and release in water 120015 EN Pilar Ferré-Pujol Research Institute for Interdisciplinary Science, Okayama University Seiji Obata Research Institute for Interdisciplinary Science, Okayama University Jésus Raya Institut de Chimie, UMR 7177 CNRS, Université de Strasbourg Alberto Bianco Research Institute for Interdisciplinary Science, Okayama University Hiroyuki Katayama Department of Urban Engineering, School of Engineering, The University of Tokyo Takashi Kato Research Center for Water Environment Technology, School of Engineering, The University of Tokyo Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University Detecting low concentrations of viruses in sewage water is crucial for monitoring the spread of emerging viral diseases. However, current detection methods, which involve concentrating viruses using traditional materials such as gauze or cotton, have limitations in effectively accomplishing this task. This study demonstrates that graphene oxide (GO), a two-dimensional carbon material, possesses strong viral adsorption capabilities. However, it lacks efficiency for effective viral release. Therefore, we designed a series of new GO-based materials, which exhibited a viral adsorption similar to pristine GO, while significantly enhancing their release performance by attaching alkyl chains and hydrophilic functional groups. Among the synthesized materials, 1,8-aminooctanol grafted to GO (GO-NH2C8OH) has emerged as the most promising candidate, achieving a viral release rate higher than 50 %. This superior performance can be attributed to the synergistic effect of the alkyl chain and the terminal OH group, which enhances both its affinity for viruses and water dispersibility. Furthermore, we have successfully applied GO-NH2C8OH in a new protocol for concentrating viruses from sewage wastewater. This approach has demonstrated a 200-fold increase in virus concentration, allowing PCR detection of this type of pathogens present in wastewater below the detection limit by direct analysis, underscoring its significant potential for virus surveillance. 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 BV Acta Medica Okayama 0006-291X 741 2024 S-adenosylmethionine and S-adenosyl-L-homocysteine metabolism is involved in the sperm motility and in vitro fertility rate in mouse 151006 EN Tomoko Kawai Department of Cellular Physiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Atsushi Fujimura Department of Cellular Physiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Increased fragmentation of sperm DNA has been implicated in male infertility. Folate deficiency results in impaired methionine synthesis, depletion of S-adenosylmethionine (SAM) levels, an increase in S-adenosyl-l-homocysteine (SAH) levels, and increased DNA fragmentation. Disruption of the dynamic balance between SAM and SAH may also contribute, although the details of this process are not yet fully understood. We investigated the localization of SAM, SAH, and S-adenosylhomocysteine hydrolase (SAHH), and whether SAM/SAH metabolism contributes to sperm motility and fertilization rate. SAM, SAH, and SAHH levels were assessed in the acrosome, midpiece, and tail of spermatozoa. Chemical inhibition of SAM/SAH metabolism and extracellular SAH significantly decreased the straight-line velocity (VSL), curvilinear velocity (VCL), and amplitude lateral head displacement (ALH) of sperm cells, which were thus unable to swim forward and perform oscillatory movements in place. This significantly reduced the fertilization rate. Therefore, the disruption of the SAM/SAH balance may contribute to male infertility. 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.

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.

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.

岡山大学文明動態学研究所 Acta Medica Okayama 2436-8326 4 2025 美作・備前・備中三国における中世宝篋印塔の地域的特徴 91 109 EN Ryo SHIBATA Okayama University, Research Institute for the Dynamics of Civilization 研究ノート (Research note) 10.18926/67958 　In this paper, the author clarifies the regional characteristics of medieval stone pagodas (hōkyō-intō 宝篋印塔) from the 13th to 14th centuries in Bizen, Bicchū, and Mimasaka provinces. The archaeological analysis was conducted typologically using 3D data from SfM and the physical and chemical analysis was conducted using magnetic susceptibility. <br> 　In Mimasaka, Bizen, and Bicchū provinces, the use of a common plan of a box-shaped pagoda was confirmed in the first half of the 14th century. In this region, the orientation of the width of the nine rings, the angle of the foundation tier shape, and other related characeristics were found to be consistent in all the analyzed pagodas.<br> 　In the latter half of the 14th century, not only did the number of pagodas increase but also pagoda shapes tended to display more variety, pointing to the possibility that several groups of stonemasons of different lineages were involved in the production of these pagodas. No potential conflict of interest relevant to this article was reported.

岡山大学文明動態学研究所 Acta Medica Okayama 2436-8326 4 2025 吉備製鉄遺跡周辺地域の磁鉄鉱ざくろ石スカルン鉄鉱石の鉱物学的・地球化学的特徴 19 52 EN Yasushi TAKECHI Kurashiki Museum of Natural History Daisuke NAKAMURA Okayama University, Department of Earth Sciences Shigeyuki SUZUKI Okayama University, Department of Earth Sciences Joseph RYAN Okayama University, Research Institute for the Dynamics of Civilizations Takeshi UWAGAKI Okayama Prefectural Board of Education Masato NAGAHARA The Historical Study Group of Mining and Metallurgy of Japan Yuta YOSHIE Mitsui Mining & Smelting Co., Ltd. Kei IKEHATA University of Tsukuba, Faculty of Life and Environmental Sciences Osamu KIMURA Okayama University, Research Institute for the Dynamics of Civilizations Ryoichi HATTORI Osaka University, Graduate School of Humanities 論文 (Research article) 10.18926/67954 We conducted mineralogical and geochemical analysis of ore samples taken from locations surrounding the Jinmu, Sanpō, and Kōmoto mines in order to determine the source of iron ore uncovered from archaeological sites. The mineral composition of the magnetite-garnet bearing skarn deposits varies from mine to mine: while clinopyroxene and amphibole are present in the Jinmu and Sanpō samples, only a small amount of clinopyroxene occurs in the Kōmoto samples. The chemical compositions of magnetite and garnet are distinctive for each mine. Among the trace elements contained in the magnetite, Mg and Mn tend to be higher in the Kōmoto samples, Ti in the Jinmu samples, and Ca and Si in the Sanpō samples. The garnet from all the mines is andradite, but while the Kōmoto samples contain almost no Al, it is present in the Jinmu and Sanpō samples. Although samples were taken from a limited number of mine areas (three), our analysis provides an index for comparison with iron ore uncovered from archaeological sites, which will aid in provenance determination. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1880-7062 45 1 2023 Mutation and apoptosis are well-coordinated for protecting against DNA damage-inducing toxicity in Drosophila 11 EN Megumi Toyoshima-Sasatani Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Fumika Imura Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Yuko Hamatake Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Akihiro Fukunaga School of Nursing, Osaka City University Tomoe Negishi Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Background Apoptotic cell death is an important survival system for multicellular organisms because it removes damaged cells. Mutation is also a survival method for dealing with damaged cells in multicellular and also unicellular organisms, when DNA lesions are not removed. However, to the best of our knowledge, no reports have comprehensively explored the direct relationship between apoptosis and somatic cell mutations induced by various mutagenic factors.<br> Results Mutation was examined by the wing-spot test, which is used to detect somatic cell mutations, including chromosomal recombination. Apoptosis was observed in the wing discs by acridine orange staining in situ. After treatment with chemical mutagens, ultraviolet light (UV), and X-ray, both the apoptotic frequency and mutagenic activity increased in a dose-dependent manner at non-toxic doses. When we used DNA repair-deficient Drosophila strains, the correlation coefficient of the relationship between apoptosis and mutagenicity, differed from that of the wild-type. To explore how apoptosis affects the behavior of mutated cells, we determined the spot size, i.e., the number of mutated cells in a spot. In parallel with an increase in apoptosis, the spot size increased with MNU or X-ray treatment dose-dependently; however, this increase was not seen with UV irradiation. In addition, BrdU incorporation, an indicator of cell proliferation, in the wing discs was suppressed at 6 h, with peak at 12 h post-treatment with X-ray, and that it started to increase again at 24 h; however, this was not seen with UV irradiation.<br> Conclusion Damage-induced apoptosis and mutation might be coordinated with each other, and the frequency of apoptosis and mutagenicity are balanced depending on the type of DNA damage. From the data of the spot size and BrdU incorporation, it is possible that mutated cells replace apoptotic cells due to their high frequency of cell division, resulting in enlargement of the spot size after MNU or X-ray treatment. We consider that the induction of mutation, apoptosis, and/or cell growth varies in multi-cellular organisms depending on the type of the mutagens, and that their balance and coordination have an important function to counter DNA damage for the survival of the organism. No potential conflict of interest relevant to this article was reported.

Japanese Society for Medical and Biological Engineering Acta Medica Okayama 2187-5219 12 2023 Transepidermal Water Loss Estimation Model for Evaluating Skin Barrier Function 1 8 EN Osamu Uehara Medical Engineering Laboratory, ALCARE Co., Ltd. Toshimasa Kusuhara Department of Radiological Technology, Graduate School of Health Sciences, Okayama University Takao Nakamura Department of Radiological Technology, Graduate School of Health Sciences, Okayama University Deterioration of skin barrier function causes symptoms such as allergies because it allows various chemical substances to enter the human body. Quantitative evaluation of the thickness and water content of the stratum corneum is useful as a measure of skin barrier function in fields such as dermatology, nursing science, and cosmetics development. The stratum corneum is responsible for most of the skin barrier function, and this function has conventionally been evaluated using transepidermal water loss (TEWL). In this paper, we propose a new model for estimation of TEWL from measurements of the thickness of the stratum corneum and water content of the surface of the stratum corneum, and discuss the results of the measurements. By measuring the thickness and water content of the stratum corneum using confocal laser microscopy and confocal Raman spectroscopy, respectively, and examining the relationship of these variables with TEWL, we established a new potential model for estimating TEWL from these two variables. The correlation coefficient of the validation data was 0.886 and the root mean squared error was 8.18 points. These findings indicate the feasibility of qualitative evaluation of TEWL by measuring the thickness and water content of the stratum corneum. No potential conflict of interest relevant to this article was reported.

Informa UK Limited Acta Medica Okayama 0038-0768 71 2 2024 Effects of aged microplastics on paddy soil properties and greenhouse gas emissions under laboratory aerobic conditions 215 224 EN Tian Zhang Graduate School of Environmental and Life Science, Okayama University Hiroaki Somura Graduate School of Environmental and Life Science, Okayama University Satoshi Akao Faculty of Science and Engineering, Doshisha University Nozomi Nakahara Environmental Management Center, Okayama University Gamamada Liyanage Erandi Priyangika Perera Graduate School of Environmental and Life Science, Okayama University Chiyu Nakano Graduate School of Natural Science and Technology, Okayama University Morihiro Maeda Graduate School of Environmental and Life Science, Okayama University Microplastics (MPs) formed after changes in chemical or physical properties may alter soil properties, which in turn may affect microbial activities and greenhouse gas (GHG) emissions. However, few studies have focused on the effects of aged MPs changes on soil properties and greenhouse gas emissions. Therefore, we aimed to investigate the impact of MPs with different aging times on soil GHG emissions and dissolved organic carbon (DOC). Low-density polyethylene (PE) and polylactic acid (PLA) were treated with ultraviolet (UV) irradiation for 0–2 weeks. Soil was incubated with PE or PLA 1% (w/w) concentration at 60% water holding capacity (WHC) for 35 days. Emissions of nitrous oxide (N2O) and carbon dioxide (CO2) were measured on days 0, 1, 3, 5, 7, 14, 21, 28, and 35. Results showed that CO2 and N2O emissions were higher (p < 0.05) in MPs-amended treatments than those without MPs and increased with MPs age. The addition of virgin PE did not affect soil DOC content, whereas aged PE and all PLA additions significantly increased soil DOC content on day 0, probably because UV irradiation caused the degradation of MPs to smaller molecules. In addition, aged MPs addition altered DOC spectral characteristics on day 7, possibly because aged PE and PLA promote microbial decomposition of organic matter by altering soil properties. Changes in soil DOC content and specific ultraviolet absorbance (SUVA) by aged PE and PLA probably promoted the emissions of CO2 and N2O compared to virgin MPs or soil only. Our study revealed that aged PE and PLA promote GHG emissions from soil by changing DOC contents and qualities. 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.

American Chemical Society (ACS) Acta Medica Okayama 1936-0851 18 49 2024 Mass Production of Graphene Oxide Beyond the Laboratory: Bridging the Gap Between Academic Research and Industry 33264 33275 EN Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University The mass production of graphene oxide (GO) has garnered significant attention in recent years due to its potential applications in various fields, from materials science to biomedicine. Graphene, known for its unique properties, such as high conductivity and mechanical strength, has been extensively studied. However, traditional production methods such as the exfoliation of graphite with scotch tape are not suitable for large-scale production. This has led to an increased focus on GO as a viable alternative to graphene production. Nonetheless, challenges, including the optimization of oxidation processes, the control of structural uniformity, and the reproducibility of production, have not been solved so far. This review critically examines GO production advancements by analyzing experimental and mechanistic studies to identify significant developments that enable high-yield and reproducible methods suitable for industrial-scale production. Special attention is given to oxidation techniques and postsynthesis purification and storage, with a focus on controlled oxidation to achieve homogeneous and single-layer GO. Through this lens, the review outlines the path forward for the industrialization of GO, aiming to bridge the gap between academic research and industrial production. No potential conflict of interest relevant to this article was reported.

Oxford University Press (OUP) Acta Medica Okayama 0009-2673 97 11 2024 Refined surface area determination of graphene oxide using methylene blue as a probe molecule: a comparative approach uoae118 EN Israel Ortiz-Anaya Graduate School of Natural Sciences and Technology, Okayama University Yuta Nishina Research Institute for Interdisciplinary Science, Okayama University In this research, we explored the effectiveness of the methylene blue adsorption method as an alternative approach for determining the specific surface area of graphene oxide. Initially, through a comparative analysis with reference activated carbon, we identified the limitations of utilizing N2 physisorption for specific surface area determination of graphene oxide. Our findings revealed that the standard pretreatment process (heating under vacuum) before N2 physisorption led to damage to the surface oxygen groups on graphene oxide, and the measured surface areas (43 m2/g) do not accurately represent the entire surface area. To optimize methylene blue coverage on graphene oxide, we conducted adsorption equilibrium experiments, focusing on controlling temperature and pH. The pH was significantly important in regulating the coverage of methylene blue. Under the optimized methylene blue adsorption conditions, the specific surface area of graphene oxide was 1,555 m2/g. Our assumptions regarding specific surface area calculations were supported by structural characterization of samples with varying methylene blue uptakes. The results confirmed a uniform coverage of methylene blue on graphene oxide by scanning electron microscopy and energy dispersive X-ray, X-ray diffraction, and atomic force microscopy. No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 2470-1343 9 50 2024 Conformational Flexibility of D1-Glu189: A Crucial Determinant in Substrate Water Selection, Positioning, and Stabilization within the Oxygen-Evolving Complex of Photosystem II 50041 50048 EN Hiroshi Isobe Research Institute for Interdisciplinary Science, Okayama University 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 is a vital process responsible for producing dioxygen and supplying the energy necessary to sustain life on Earth. This fundamental reaction is catalyzed by the oxygen-evolving complex (OEC) of photosystem II, which houses the Mn4CaO5 cluster as its catalytic core. In this study, we specifically focus on the D1-Glu189 amino acid residue, which serves as a direct ligand to the Mn4CaO5 cluster. Our primary goal is to explore, using density functional theory (DFT), how the conformational flexibility of the D1-Glu189 side chain influences crucial catalytic processes, particularly the selection, positioning, and stabilization of a substrate water molecule within the OEC. Our investigation is based on a hypothesis put forth by Li et al. (Nature, 2024, 626, 670), which suggests that during the transition from the S2 to S3 state, a specific water molecule temporarily coordinating with the Ca ion, referred to as O6*, may exist as a hydroxide ion (OH-). Our results demonstrate a key mechanism by which the detachment of the D1-Glu189 carboxylate group from its coordination with the Ca ion allows the creation of a specialized microenvironment within the OEC that enables the selective attraction of O6* in its deprotonated form (OH-) and stabilizes it at the catalytic metal (MnD) site. Our findings indicate that D1-Glu189 is not only a structural ligand for the Ca ion but may also play an active and dynamic role in the catalytic process, positioning O6* optimally for its subsequent participation in the oxidation sequence during the water-splitting cycle. 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.

MDPI Acta Medica Okayama 1424-8220 24 22 2024 Microdetection of Nucleocapsid Proteins via Terahertz Chemical Microscope Using Aptamers 7382 EN Xue Ding Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Mana Murakami Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Jin Wang Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Hirofumi Inoue Graduate School of Medicine Dentistry and Pharmaceutical Sciences, Okayama University Hospital Toshihiko Kiwa Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University In the detection of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), several methods have been employed, including the detection of viral ribonucleic acid (RNA), nucleocapsid (N) proteins, spike proteins, and antibodies. RNA detection, primarily through polymerase chain reaction tests, targets the viral genetic material, whereas antigen tests detect N and spike proteins to identify active infections. In addition, antibody tests are performed to measure the immune response, indicating previous exposure or vaccination. Here, we used the developed terahertz chemical microscope (TCM) to detect different concentrations of N protein in solution by immobilizing aptamers on a semiconductor substrate (sensing plate) and demonstrated that the terahertz amplitude varies as the concentration of N proteins increases, exhibiting a highly linear relationship with a coefficient of determination (R2 = 0.9881), indicating that a quantitative measurement of N proteins is achieved. By optimizing the reaction conditions, we confirmed that the amplitude of the terahertz wave was independent of the solution volume. Consequently, trace amounts (0.5 μL) of the N protein were successfully detected, and the detection process only took 10 min. Therefore, this study is expected to develop a rapid and sensitive method for the detection and observation of the SARS-CoV-2 virus at a microdetection level. It is anticipated that this research will significantly contribute to reducing the spread of novel infectious diseases in the future. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1661-6596 25 21 2024 Epigenetic Regulation of CXC Chemokine Expression by Environmental Electrophiles Through DNA Methyltransferase Inhibition 11592 EN Tomoki Tsuchida Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Sho Kubota Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shizuki Kamiuezono Department of Medicinal Pharmacology, Faculty of Pharmaceutical Sciences, Okayama University Nobumasa Takasugi Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Ito School of Life Sciences, Tokyo University of Pharmacy and Life Sciences Yoshito Kumagai Graduate School of Pharmaceutical Sciences, Kyushu University Takashi Uehara Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ubiquitously distributed environmental electrophiles covalently modify DNA and proteins, potentially leading to adverse health effects. However, the impacts of specific electrophiles on target proteins and their physiological roles remain largely unknown. In the present study, we focused on DNA methylation, which regulates gene expression and physiological responses. A total of 45 environmental electrophiles were screened for inhibitory effects on the activity of DNA methyltransferase 3B (DNMT3B), a key enzyme in DNA methylation, and four compounds were identified. We focused on 1,2-naphthoquinone (1,2-NQ), an air pollutant whose toxicity has been reported previously. Interestingly, we found that 1,2-NQ modified multiple lysine and histidine residues in DNMT3B, one of which was near the active site in DNMT3B. It was found that 1,2-NQ altered gene expression and evoked inflammatory responses in lung adenocarcinoma cell lines. Furthermore, we found that 1,2-NQ upregulated CXCL8 expression through DNA demethylation of the distal enhancer and promoted cancer cell growth. Our study reveals novel mechanisms of epigenetic regulation by environmental electrophiles through the inhibition of DNMT3B activity and suggests their physiological impact. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 1083-351X 300 3 2024 Methyl vinyl ketone and its analogs covalently modify PI3K and alter physiological functions by inhibiting PI3K signaling 105679 EN Atsushi Morimoto Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Nobumasa Takasugi Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuexuan Pan Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Sho Kubota Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Naoshi Dohmae Biomolecular Characterization Unit, Technology Platform Division, RIKEN Center for Sustainable Resource Science Yumi Abiko Graduate School of Biomedical Science, Nagasaki University Koji Uchida Laboratory of Food Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo Yoshito Kumagai Graduate School of Pharmaceutical Sciences, Kyushu University Takashi Uehara Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Reactive carbonyl species (RCS), which are abundant in the environment and are produced in vivo under stress, covalently bind to nucleophilic residues such as Cys in proteins. Disruption of protein function by RCS exposure is predicted to play a role in the development of various diseases such as cancer and metabolic disorders, but most studies on RCS have been limited to simple cytotoxicity validation, leaving their target proteins and resulting physiological changes unknown. In this study, we focused on methyl vinyl ketone (MVK), which is one of the main RCS found in cigarette smoke and exhaust gas. We found that MVK suppressed PI3K-Akt signaling, which regulates processes involved in cellular homeostasis, including cell proliferation, autophagy, and glucose metabolism. Interestingly, MVK inhibits the interaction between the epidermal growth factor receptor and PI3K. Cys656 in the SH2 domain of the PI3K p85 subunit, which is the covalently binding site of MVK, is important for this interaction. Suppression of PI3K- Akt signaling by MVK reversed epidermal growth factor- induced negative regulation of autophagy and attenuated glucose uptake. Furthermore, we analyzed the effects of the 23 RCS compounds with structures similar to MVK and showed that their analogs also suppressed PI3K-Akt signaling in a manner that correlated with their similarities to MVK. Our study demonstrates the mechanism of MVK and its analogs in suppressing PI3K-Akt signaling and modulating physiological functions, providing a model for future studies analyzing environmental reactive species. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0743-7463 40 43 2024 Nanoscale Structures of Tough Microparticle-Based Films Investigated by Synchrotron X-Ray Scattering and All-Atom Molecular-Dynamics Simulation 22614 22626 EN Keita Namba Department of Frontier Materials Chemistry, Graduate School of Science and Technology, Hirosaki University Yuma Sasaki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuto Kawamura Graduate School of Textile Science &Technology, Shinshu University Shotaro Yoshida Department of Materials Chemistry, Nagoya University Yoshiki Hieda Department of Chemistry and Materials Engineering, Faculty of Chemistry, Materials and Bioengineering, Kansai University Kazushi Fujimoto Department of Chemistry and Materials Engineering, Faculty of Chemistry, Materials and Bioengineering, Kansai University Natsuki Watanabe Department of Physics, Nagoya University Yuichiro Nishizawa Department of Physics, Nagoya University Takayuki Uchihashi Department of Physics, Nagoya University Daisuke Suzuki 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 In this study, the nanoscale structures of microparticle-based films are revealed by synchrotron small-angle X-ray scattering (SAXS) and all-atom molecular-dynamics (AA-MD) simulations. The microparticle-based films consisting of the simplest acrylate polymer microparticles are applied as a model because the films are formed without additives and organic solvents and exhibit high toughness properties. The characteristic interfacial thickness (tinter) obtained from the SAXS analysis reflects the mixing degree of polymer chains on the microparticle surface in the film. The cross-linking density of inner microparticles is found to be strongly correlated to not only several properties of individual microparticles, such as swelling ratio and radius of gyration, but also the tinter and toughness of the corresponding films. Therefore, the tinter and toughness values follow a linear relationship because the cross-linking restricts the mixing of polymer chains between their surfaces in the film, which is a unique feature of microparticle-based films. This characteristic also affects their deformation behavior observed by in situ SAXS during tensile testing and their density profiles calculated by AA-MD simulations. This work provides a general strategy for material design to control the physical properties and structures of their films for advanced applications, including volatile organic compound-free sustainable coatings and adhesives. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0340-5761 99 2 2024 Therapeutic potential of 4-phenylbutyric acid against methylmercury-induced neuronal cell death in mice 563 574 EN Ryohei Miki Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ryosuke Nomura Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuta Iijima Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Sho Kubota Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Nobumasa Takasugi Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takao Iwawaki Division of Cell Medicine, Department of Life Science, Medical Research Institute, Kanazawa Medical University Masatake Fujimura Department of International Affairs and Research, National Institute for Minamata Disease Takashi Uehara Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Methylmercury (MeHg) is an environmental neurotoxin that induces damage to the central nervous system and is the causative agent in Minamata disease. The mechanisms underlying MeHg neurotoxicity remain largely unknown, and there is a need for effective therapeutic agents, such as those that target MeHg-induced endoplasmic reticulum (ER) stress and the unfolded protein response (UPR), which is activated as a defense mechanism. We investigated whether intraperitoneal administration of the chemical chaperone, 4-phenylbutyric acid (4-PBA), at 120 mg/kg/day can alleviate neurotoxicity in the brains of mice administered 50 ppm MeHg in drinking water for 5 weeks. 4-PBA significantly reduced MeHg-induced ER stress, neuronal apoptosis, and neurological symptoms. Furthermore, 4-PBA was effective even when administered 2 weeks after the initiation of exposure to 30 ppm MeHg in drinking water. Our results strongly indicate that ER stress and the UPR are key processes involved in MeHg toxicity, and that 4-PBA is a novel therapeutic candidate for MeHg-induced neurotoxicity. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 2352-409X 60 2024 Petrological characterization for material provenance of haniwa earthenware from mounded tombs in the Kibi region, Japan 104813 EN Toshio Nozaka Department of Earth Sciences, Okayama University Naoya Ohbayashi Department of Earth Sciences, Okayama University Yuki Toda Department of Earth Sciences, Okayama University Kanako Sugiura Department of Archaeology, Okayama University Takahiro Nozaki Research Institute for the Dynamics of Civilizations, Okayama University Osamu Kimura Research Institute for the Dynamics of Civilizations, Okayama University Naoko Matsumoto Research Institute for the Dynamics of Civilizations, Okayama University Akira Seike Department of Archaeology, Okayama University To determine the provenance of the materials used in the production of haniwa earthenware unearthed from mounded tombs (kofun) in the Kibi region (modern Okayama Prefecture) during the Kofun period (late 3rd – 6th century CE) of Japan, we carried out petrological analyses of haniwa sherds, including optical microscopy, X-ray diffractometry, X-ray fluorescence spectroscopy, and electron-probe analysis. The 25 haniwa sherds analyzed from 12 representative mounded tombs are composed of mineral and rock inclusions with variable grain size set in a clay matrix. The dominant inclusions are quartz, K-feldspar, and plagioclase, associated with minor amounts of amphibole, volcanic glass, and granitic rocks in all the haniwa sherds, and small amounts of hornfels, quartz rock, and accessory minerals, including mica, ilmenite, and chromite, in some of the sherds. Amphibole and plagioclase have compositional variations indicative of the mixing of tephra and granitic components. The compositions of volcanic glass inclusions are similar to those of the Aira-Tanzawa and Kikai-Akahoya tephras widely distributed in southwestern Japan. Bulk chemical compositions show magmatic differentiation trends, which are variable between individual tombs. From these results, it is concluded that the paste materials of haniwa in the Kibi region were commonly derived from weathered granitic rocks mixed with minor amounts of three widespread tephras. The variations of chemical and mineralogical compositions are probably the reflection of local geologic settings, suggesting the presence of specific mining sites of paste materials around each tomb. The mining sites could be located at the bases of hills of granitic rocks covered by widespread tephras and in some cases, near the flood plain of big river systems. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1364-548X 60 93 2024 Machine-learning-assisted prediction of the size of microgels prepared by aqueous precipitation polymerization 13678 13681 EN Daisuke Suzuki Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haruka Minato Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Yuji Sato Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Ryuji Namioka Graduate School of Textile Science & Technology, Shinshu University Yasuhiko Igarashi Faculty of Engineering, Information and Systems, University of Tsukuba Risako Shibata Department of Applied Chemistry, Faculty of Science and Technology, Keio University Yuya Oaki Department of Applied Chemistry, Faculty of Science and Technology, Keio University The size of soft colloids (microgels) is essential; however, control over their size has typically been established empirically. Herein, we report a linear-regression model that can predict microgel size using a machine learning method, sparse modeling for small data, which enables the determination of the synthesis conditions for target-sized microgels. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1618-2642 416 28 2024 Comparison of protein immobilization methods with covalent bonding on paper for paper-based enzyme-linked immunosorbent assay 6679 6686 EN Yang Chen Department of Chemistry, Okayama University Kaewta Danchana Department of Chemistry, Okayama University Takashi Kaneta Department of Chemistry, Okayama University In this study, two methods were examined to optimize the immobilization of antibodies on paper when conducting a paper-based enzyme-linked immunosorbent assay (P-ELISA). Human IgG, as a test-capture protein, was immobilized on paper via the formation of Schiff bases. Aldehyde groups were introduced onto the surface of the paper via two methods: NaIO4 and 3-aminopropyltriethoxysilane (APTS) with glutaraldehyde (APTS-glutaraldehyde). In the assay, horseradish peroxidase-conjugated anti-human IgG (HRP-anti-IgG) binds to the immobilized human IgG, and the colorimetric reaction of 3,3′,5,5′-tetramethylbenzyzine (TMB) produces a blue color in the presence of H2O2 and HRP-anti-IgG as a model analyte. The immobilization of human IgG, the enzymatic reaction conditions, and the reduction of the chemical bond between the paper surface and immobilized human IgG all were optimized in order to improve both the analytical performance and the stability. In addition, the thickness of the paper was examined to stabilize the analytical signal. Consequently, the APTS-glutaraldehyde method was superior to the NaIO4 method in terms of sensitivity and reproducibility. Conversely, the reduction of imine to amine with NaBH4 proved to exert only minimal influence on sensitivity and stability, although it tended to degrade reproducibility. We also found that thick paper was preferential when using P-ELISA because a rigid paper substrate prevents distortion of the paper surface that is often caused by repeated washing processes. No potential conflict of interest relevant to this article was reported.

Anticancer Research USA Inc. Acta Medica Okayama 1109-6535 21 5 2024 Terrein Exhibits Anti-tumor Activity by Suppressing Angiogenin Expression in Malignant Melanoma Cells 464 473 EN TAIRA HIROSE Department of Oral and Maxillofacial Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences YUKI KUNISADA Department of Oral and Maxillofacial Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences KOICHI KADOYA Department of Oral and Maxillofacial Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences HIROKI MANDAI Department of Pharmacy, Faculty of Pharmacy, Gifu University of Medical Science YUMI SAKAMOTO Department of Oral and Maxillofacial Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences KYOICHI OBATA Department of Oral and Maxillofacial Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences KISHO ONO Department of Oral and Maxillofacial Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences HIROAKI TAKAKURA Department of Oral and Maxillofacial Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences KAZUHIRO OMORI Department of Pathophysiology-Periodontal Science, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University SHOGO TAKASHIBA Department of Pathophysiology-Periodontal Science, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University SEIJI SUGA Division of Applied Chemistry, Graduate School of Natural Sciences and Technology, Okayama University SOICHIRO IBARAGI Department of Oral and Maxillofacial Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Background/Aim: Malignant melanoma is a tumor with a poor prognosis that can metastasize distally at an early stage. Terrein, a metabolite produced by Aspergillus terreus, suppresses the expression of angiogenin, an angiogenic factor. However, the pharmacological effects of natural terrein have not been elucidated, because only a small amount of terrein can be extracted from large fungal cultures. In this study, we investigated the antineoplastic effects of terrein on human malignant melanoma cells and its underlying mechanisms. Materials and methods: Human malignant melanoma cell lines were cultured in the presence of terrein and analyzed. Angiogenin production was evaluated using ELISA. Ribosome biosynthesis was evaluated using silver staining of the nucleolar organizer region. Intracellular signaling pathways were analyzed using western blotting. Malignant melanoma cells were transplanted subcutaneously into the backs of nude mice. The tumors were removed at 5 weeks and analyzed histopathologically. Results: Terrein inhibited angiogenin expression, proliferation, migration, invasion, and ribosome biosynthesis in malignant melanoma cells. Terrein was shown to inhibit tumor growth and angiogenesis in animal models. Conclusion: This study demonstrated that terrein has anti-tumor effects against malignant melanoma. Furthermore, chemically synthesized non-natural terrein can be mass-produced and serve as a novel potential anti-tumor drug candidate. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0743-7463 40 32 2024 Effect of Droplet-Removal Processes on Fog-Harvesting Performance on Wettability-Controlled Wire Array with Staggered Arrangement 16994 17000 EN Yutaka Yamada Faculty of Environmental, Life, Natural Science and Technology, Okayama University Junya Oka Graduate School of Natural Science and Technology, Okayama University Kazuma Isobe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Akihiko Horibe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Development of freshwater resources is vital to overcoming severe worldwide water scarcity. Fog harvesting has attracted attention as a candidate technology that can be used to obtain fresh water from a stream of foggy air without energy input. Drainage of captured droplets from fog harvesters is necessary to maintain the permeability of harp-shaped harvesters. In the present study, we investigated the effect of the droplet-removal process on the amount of water harvested using a harvester constructed by wettability-controlled wires with an alternating and staggered arrangement. Droplet transfer from hydrophobic to hydrophilic wires, located upstream and downstream of the fog flow, respectively, was observed with a fog velocity greater than 1.5 m/s. The proportion of harvesting resulting from droplet transfer exceeded 30% of the total, and it reflected more than 20% increase of the harvesting performance compared with that of a harvester with wires of the same wettability: this value varied with the adhesive property of the wires and fog velocity. Scaled-up and multilayered harvesters were developed to enhance harvesting performance. We demonstrated certain enhancements under multilayered conditions and obtained 15.99 g/30 min as the maximum harvested amount, which corresponds to 13.3% of the liquid contained in the fog stream and is enhanced by 10% compared with that without droplet transfer. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry Acta Medica Okayama 2633-0679 5 9 2024 Novel strategy for activating gene expression through triplex DNA formation targeting epigenetically suppressed genes 884 890 EN Ryotaro Notomi Graduate School of Pharmaceutical Sciences, Kyushu University Shigeki Sasaki Graduate School of Pharmaceutical Sciences, Nagasaki International University Yosuke Taniguchi Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Triplex DNA formation is a useful genomic targeting tool that is expected to have a wide range of applications, including the antigene method; however, there are fundamental limitations in its forming sequence. We recently extended the triplex DNA-forming sequence to methylated DNA sequences containing 5mCG base pairs by developing guanidino-dN, which is capable of recognizing a 5mCG base pair with high affinity. We herein investigated the effect of triplex DNA formation using TFOs with guanidino-dN on methylated DNA sequences at the promoter of the RASSF1A gene, whose expression is epigenetically suppressed by DNA methylation in MCF-7 cells, on gene expression. Interestingly, triplex DNA formation increased the expression of the RASSF1A gene at the transcript and protein levels. Furthermore, RASSF1A-activated MCF-7 cells exhibited cell growth suppressing activity. Changes in the expression of various genes associated with the promotion of apoptosis and breast cancer survival accompanied the activation of RASSF1A in cells exhibited antiproliferative activity. These results suggest the potential of increases in gene expression through triplex DNA formation as a new genomic targeting tool. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry Acta Medica Okayama 2041-6520 15 32 2024 Boosting charge separation in organic photovoltaics: unveiling dipole moment variations in excited non-fullerene acceptor layers 12686 12694 EN Akira Yamakata Graduate School of Natural Science and Technology, Okayama University Kosaku Kato Graduate School of Natural Science and Technology, Okayama University Takumi Urakami Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Sota Tsujimura Department of Chemistry, Graduate School of Science, Kobe University Kasumi Murayama Department of Chemistry, Graduate School of Science, Kobe University Masahiro Higashi Department of Complex Systems Science, Graduate School of Informatics, Nagoya University Hirofumi Sato Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Yasuhiro Kobori Department of Chemistry, Graduate School of Science, Kobe University Tomokazu Umeyama Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo Hiroshi Imahori Department of Molecular Engineering, Graduate School of Engineering, Kyoto University The power conversion efficiency (PCE) of organic photovoltaics (OPVs) has reached more than 19% due to the rapid development of non-fullerene acceptors (NFAs). To compete with the PCEs (26%) of commercialized silicon-based inorganic photovoltaics, the drawback of OPVs should be minimized. This drawback is the intrinsic large loss of open-circuit voltage; however, a general approach to this issue remains elusive. Here, we report a discovery regarding highly efficient NFAs, specifically ITIC. We found that charge-transfer (CT) and charge dissociation (CD) can occur even in a neat ITIC film without the donor layer. This is surprising, as these processes were previously believed to take place exclusively at donor/acceptor heterojunctions. Femtosecond time-resolved visible to mid-infrared measurements revealed that in the neat ITIC layers, the intermolecular CT immediately proceeds after photoirradiation (<0.1 ps) to form weakly-bound excitons with a binding energy of 0.3 eV, which are further dissociated into free electrons and holes with a time-constant of 56 ps. Theoretical calculations indicate that stacking faults in ITIC (i.e., V-type molecular stacking) induce instantaneous intermolecular CT and CD in the neat ITIC layer. In contrast, J-type stacking does not support such CT and CD. This previously unknown pathway is triggered by the larger dipole moment change on the excited state generated at the lower symmetric V-type molecular stacking of ITIC. This is in sharp contrast with the need of sufficient energy offset for CT and CD at the donor-acceptor heterojunction, leading to the significant voltage loss in conventional OPVs. These results demonstrate that the rational molecular design of NFAs can increase the local dipole moment change on the excited state within the NFA layer. This finding paves the way for a groundbreaking route toward the commercialization of OPVs. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0022-3263 89 14 2024 Formal One Carbon Deletion of Indoline Hemiaminals under Tautomeric Control to Access 2-Aminobenzyl Compounds 10349 10354 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 Unprecedented tert-BuOK-mediated one carbon deletion of indoline hemiaminals has been achieved. This novel protocol provides an efficient synthetic tool for the construction of 2-aminobenzyl compounds with high chemoselectivity. In addition, functionalized 2-aminobenzyl compounds are difficult to make, for which few limited means of access currently exist. The key to success is the use of in situ generated Heyns rearrangement products (α-amino carbonyl compounds) as precursors for formal one carbon deletion. No potential conflict of interest relevant to this article was reported.

Beilstein-Institut Acta Medica Okayama 1860-5397 20 2024 Electrocatalytic hydrogenation of cyanoarenes, nitroarenes, quinolines, and pyridines under mild conditions with a proton-exchange membrane reactor 1560 1571 EN Koichi Mitsudo Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Atsushi Osaki Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Haruka Inoue 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 Naoki Shida Graduate School of Engineering Science and Advanced Chemical Energy Research Center, Yokohama National University Mahito Atobe Graduate School of Engineering Science and Advanced Chemical Energy Research Center, Yokohama National University Seiji Suga Division of Applied Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University An electrocatalytic hydrogenation of cyanoarenes, nitroarenes, quinolines, and pyridines using a proton-exchange membrane (PEM) reactor was developed. Cyanoarenes were then reduced to the corresponding benzylamines at room temperature in the presence of ethyl phosphate. The reduction of nitroarenes proceeded at room temperature, and a variety of anilines were obtained. The quinoline reduction was efficiently promoted by adding a catalytic amount of p-toluenesulfonic acid (PTSA) or pyridinium p-toluenesulfonate (PPTS). Pyridine was also reduced to piperidine in the presence of PTSA. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1520-6106 128 27 2024 Bidirectional Optical Control of Proton Motive Force in Escherichia coli Using Microbial Rhodopsins 6509 6517 EN Kotaro Nakanishi Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Keiichi Kojima Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yoshiyuki Sowa Department of Frontier Bioscience and Research Center for Micro-Nano Technology, Hosei University Yuki Sudo Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Proton (H+) motive force (PMF) serves as the energy source for the flagellar motor rotation, crucial for microbial motility. Here, to control PMF using light, we introduced light-driven inward and outward proton pump rhodopsins, RmXeR and AR3, into Escherichia coli. The motility of E. coli cells expressing RmXeR and AR3 significantly decreased and increased upon illumination, respectively. Tethered cell experiments revealed that, upon illumination, the torque of the flagellar motor decreased to nearly zero (28 pN nm) with RmXeR, while it increased to 1170 pN nm with AR3. These alterations in PMF correspond to +146 mV (RmXeR) and −140 mV (AR3), respectively. Thus, bidirectional optical control of PMF in E. coli was successfully achieved by using proton pump rhodopsins. This system holds a potential for enhancing our understanding of the roles of PMF in various biological functions. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-7345 60 52 2024 Switchable synthesis of 3-aminoindolines and 2′-aminoarylacetic acids using Grignard reagents and 3-azido-2-hydroxyindolines 6615 6618 EN Toshiki Yamashiro Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takumi Abe Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University The switchable synthesis of 3-aminoindolines and 2′-aminoaryl acetic acids from the same substrates, 3-azido-2-hydroxyindolines, was developed through denitrogenative electrophilic amination of Grignard reagents. The key to success is the serendipitous discovery that the reaction conditions, including solvents and reaction temperature, can affect the chemoselectivity. It is noteworthy that isotope-labeling experiments revealed the occurrence of the aziridine intermediate in the production of 2′-aminoaryl acetic acids. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2073-4409 13 10 2024 Exploring the Regulators of Keratinization: Role of BMP-2 in Oral Mucosa 807 EN Xindi Mu Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Mitsuaki Ono Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Ha Thi Thu Nguyen Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Ziyi Wang Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kun Zhao Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Taishi Komori Tomoko Yonezawa Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Takuo Kuboki Department of Oral Rehabilitation and Implantology, Okayama University Hospital Toshitaka Oohashi Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences The oral mucosa functions as a physico-chemical and immune barrier to external stimuli, and an adequate width of the keratinized mucosa around the teeth or implants is crucial to maintaining them in a healthy and stable condition. In this study, for the first time, bulk RNA-seq analysis was performed to explore the gene expression of laser microdissected epithelium and lamina propria from mice, aiming to investigate the differences between keratinized and non-keratinized oral mucosa. Based on the differentially expressed genes (DEGs) and Gene Ontology (GO) Enrichment Analysis, bone morphogenetic protein 2 (BMP-2) was identified to be a potential regulator of oral mucosal keratinization. Monoculture and epithelial-mesenchymal cell co-culture models in the air-liquid interface (ALI) indicated that BMP-2 has direct and positive effects on epithelial keratinization and proliferation. We further performed bulk RNA-seq of the ALI monoculture stimulated with BMP-2 in an attempt to identify the downstream factors promoting epithelial keratinization and proliferation. Analysis of the DEGs identified, among others, IGF2, ID1, LTBP1, LOX, SERPINE1, IL24, and MMP1 as key factors. In summary, these results revealed the involvement of a well-known growth factor responsible for bone development, BMP-2, in the mechanism of oral mucosal keratinization and proliferation, and pointed out the possible downstream genes involved in this mechanism. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2024 One-Pot Synthesis of Chemicals Using CO2 as Chemical Feedstock EN Koichi NAKAOKA Graduate School of Natural Science and Technology, Okayama university No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 2470-1343 9 19 2024 Superstructure of Fe5–xGeTe2 Determined by Te K-Edge Extended X-ray Absorption Fine Structure and Te Kα X-ray Fluorescence Holography 21287 21297 EN Ritsuko Eguchi Research Institute for Interdisciplinary Science, Okayama University Halubai Sekhar Department of Physical Science and Technology, Nagoya Institute of Technology Koji Kimura Department of Physical Science and Technology, Nagoya Institute of Technology Hirokazu Masai Department of Materials and Chemistry, National Institute of Advanced Industrial Science and Technology (AIST) Naohisa Happo Graduate School of Information Sciences, Hiroshima City University Mitsuki Ikeda Research Institute for Interdisciplinary Science, Okayama University Yuki Yamamoto Research Institute for Interdisciplinary Science, Okayama University Masaki Utsumi Research Institute for Interdisciplinary Science, Okayama University Hidenori Goto Research Institute for Interdisciplinary Science, Okayama University Yasuhiro Takabayashi Department of Physical Science and Technology, Nagoya Institute of Technology Hiroo Tajiri Japan Synchrotron Radiation Research Institute (JASRI) Koichi Hayashi Department of Physical Science and Technology, Nagoya Institute of Technology Yoshihiro Kubozono Research Institute for Interdisciplinary Science, Okayama University The local structure of the two-dimensional van der Waals material, Fe5–xGeTe2, which exhibits unique structural/magnetic phase transitions, was investigated by Te K-edge extended X-ray absorption fine structure (EXAFS) and Te Kα X-ray fluorescence holography (XFH) over a wide temperature range. The formation of a trimer of Te atoms at low temperatures has been fully explored using these methods. An increase in the Te–Fe distance at approximately 150 K was suggested by EXAFS and presumably indicates the formation of a Te trimer. Moreover, XFH displayed clear atomic images of Te atoms. Additionally, the distance between the Te atoms shortened, as confirmed from the atomic images reconstructed from XFH, indicating the formation of a trimer of Te atoms, i.e., a charge-ordered (3⎯⎯√×3⎯⎯√)𝑅30◦ superstructure. Furthermore, Te Kα XFH provided unambiguous atomic images of Fe atoms occupying the Fe1 site; the images were not clearly observed in the Ge Kα XFH that was previously reported because of the low occupancy of Fe and Ge atoms. In this study, EXAFS and XFH clearly showed the local structure around the Te atom; in particular, the formation of Te trimers caused by charge-ordered phase transitions was clearly confirmed. The charge-ordered phase transition is fully discussed based on the structural variation at low temperatures, as established from EXAFS and XFH. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0002-7863 146 22 2024 Skeletal Formation of Carbocycles with CO2: Selective Synthesis of Indolo[3,2-b]carbazoles or Cyclophanes from Indoles, CO2, and Phenylsilane 14935 14941 EN Sha Li Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Shoko Nakahara Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Taishin Adachi Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Takumi Murata Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Kazuto Takaishi 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 The catalytic reactions of indoles with CO2 and phenylsilane afforded indolo[3,2-b]carbazoles, where the fused benzene ring was constructed by forming two C–H bonds and four C–C bonds with two CO2 molecules via deoxygenative conversions. Nine-membered cyclophanes made up of three indoles and three CO2 molecules were also obtained, where the cyclophane framework was constructed by forming six C–H bonds and six C–C bonds. These multicomponent cascade reactions giving completely different carbocycles were switched simply by choosing the solvent, acetonitrile or ethyl acetate. No potential conflict of interest relevant to this article was reported.

Oxford University Press (OUP) Acta Medica Okayama 0021-924X 174 5 2023 Direct binding of calmodulin to the cytosolic C-terminal regions of sweet/umami taste receptors 451 459 EN Atsuki Yoshida Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ayumi Ito Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Norihisa Yasui Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Atsuko Yamashita Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Sweet and umami taste receptors recognize chemicals such as sugars and amino acids on their extracellular side and transmit signals into the cytosol of the taste cell. In contrast to ligands that act on the extracellular side of these receptors, little is known regarding the molecules that regulate receptor functions within the cytosol. In this study, we analysed the interaction between sweet and umami taste receptors and calmodulin, a representative Ca2+-dependent cytosolic regulatory protein. High prediction scores for calmodulin binding were observed on the C-terminal cytosolic side of mouse taste receptor type 1 subunit 3 (T1r3), a subunit that is common to both sweet and umami taste receptors. Pull-down assay and surface plasmon resonance analyses showed different affinities of calmodulin to the C-terminal tails of distinct T1r subtypes. Furthermore, we found that T1r3 and T1r2 showed the highest and considerable binding to calmodulin, whereas T1r1 showed weaker binding affinity. Finally, the binding of calmodulin to T1rs was consistently higher in the presence of Ca2+ than in its absence. The results suggested a possibility of the Ca2+-dependent feedback regulation process of sweet and umami taste receptor signaling by calmodulin. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1932-7447 127 25 2023 Li-Ion Transport and Solution Structure in Sulfolane-Based Localized High-Concentration Electrolytes 12295 12303 EN Taku Sudoh Taku Sudoh Department of Chemistry and Life Science, Yokohama National University Shuhei Ikeda Department of Materials Chemistry, Nagoya University Keisuke Shigenobu Department of Chemistry and Life Science, Yokohama National University Seiji Tsuzuki Advanced Chemical Energy Research Centre (ACERC), Institute of Advanced Sciences, Yokohama National University Kaoru Dokko Department of Chemistry and Life Science, Yokohama National University Masayoshi Watanabe Advanced Chemical Energy Research Centre (ACERC), Institute of Advanced Sciences, Yokohama National University Wataru Shinoda Research Institute for Interdisciplinary Science and Department of Chemistry, Okayama University Kazuhide Ueno Department of Chemistry and Life Science, Yokohama National University Localized high-concentration electrolytes (LHCEs), which are mixtures of highly concentrated electrolytes (HCEs) and non-coordinating diluents, have attracted significant interest as promising liquid electrolytes for next-generation Li secondary batteries, owing to their various beneficial properties both in the bulk and at the electrode/electrolyte interface. We previously reported that the large Li+-ion transference number in sulfolane (SL)-based HCEs, attributed to the unique exchange/hopping-like Li+-ion conduction, decreased upon dilution with the non-coordinating hydrofluoroether (HFE) despite the retention of the local Li+-ion coordination structure. Therefore, in this study, we investigated the effects of HFE dilution on the Li+ transference number and the solution structure of SL-based LHCEs via the analysis of dynamic ion correlations and molecular dynamics simulations. The addition of HFE caused nano-segregation in the SL-based LHCEs to afford polar and nonpolar domains and fragmentation of the polar ion-conducting pathway into smaller clusters with increasing HFE content. Analysis of the dynamic ion correlations revealed that the anti-correlated Li+–Li+ motions were more pronounced upon HFE addition, suggesting that the Li+ exchange/hopping conduction is obstructed by the non-ion-conducting HFE-rich domains. Thus, the HFE addition affects the entire solution structure and ion transport without significantly affecting the local Li+-ion coordination structure. Further studies on ion transport in LHCEs would help obtain a design principle for liquid electrolytes with high ionic conductivity and large Li+-ion transference numbers. No potential conflict of interest relevant to this article was reported.

AIP Publishing Acta Medica Okayama 0021-9606 160 14 2024 Analysis on high-resolution spectrum of the S1–S0 transition of free-base phthalocyanine 144304 EN Yuki Miyamoto Research Institute for Interdisciplinary Science, Okayama University Ayami Hiramoto Research Institute for Interdisciplinary Science, Okayama University Kana Iwakuni Institute for Laser Science, University of Electro-Communications Susumu Kuma Atomic, Molecular and Optical Physics Laboratory, RIKEN Katsunari Enomoto Department of Physics, University of Toyama Naofumi Nakayama CONFLEX Corporation Masaaki Baba Molecular Photoscience Research Center, Kobe University A high-resolution absorption spectrum of the S-1-S-0 transition of free-base phthalocyanine was observed and analyzed with improved reliability. The spectrum, with a partially resolved rotational structure, was obtained by using the buffer-gas cooling technique and a single-mode tunable laser. Our new analysis reveals that the S-1 <- S-0 0(0)(0) band belongs to the a-type transition, where the electronic transition moment aligns parallel to the NH-HN direction, allowing the assignment of the S-1 state to B-1(3u). These results agree with a prior study using supersonic expansion and are well supported by theoretical calculations. Interestingly, the rotational constant B in the S-1 state, which is often smaller than that in the ground state for typical molecules, was found to be slightly larger than that in the S-0 (1)A(g) state. This suggests a change in the character of pi bonds with the electronic excitation. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2075-163X 14 4 2024 Changes of Temperature and Moisture Distribution over Time by Thermo-Hydro-Chemical (T-H-C)-Coupled Analysis in Buffer Material Focusing on Montmorillonite Content 394 EN Kohei Ouchi Graduate School of Natural Science and Technology, Okayama University Haruo Sato Graduate School of Natural Science and Technology, Okayama University Bentonite is used as a buffer material in engineered barriers for the geological disposal of high-level radioactive waste. The buffer material will be made of bentonite, a natural clay, mixed with silica sand. The buffer material is affected by decay heat from high-level radioactive waste, infiltration of groundwater, and swelling of the buffer material. The analysis of these factors requires coupled analysis of heat transfer, moisture transfer, and groundwater chemistry. The purpose of this study is to develop a model to evaluate bentonite types and silica sand content in a unified manner for thermo-hydro-chemical (T-H-C)-coupled analysis in buffer materials. We focused on the content of the clay mineral montmorillonite, which is the main component of bentonite, and developed a model to derive the moisture diffusion coefficient of liquid water and water vapor based on Philip and de Vries, and Kozeny-Carman. The evolutions of the temperature and moisture distribution in the buffer material were analyzed, and the validity of each distribution was confirmed by comparison with the measured data obtained from an in situ experiment at 350 m in depth at the Horonobe Underground Research Center, Hokkaido, Japan. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-7345 59 17 2023 Non-enzymatic detection of glucose levels in human blood plasma by a graphene oxide-modified organic transistor sensor 2425 2428 EN Haonan Fan Institute of Industrial Science, The University of Tokyo Yui Sasaki Institute of Industrial Science, The University of Tokyo Qi Zhou Institute of Industrial Science, The University of Tokyo Wei Tang Institute of Industrial Science, The University of Tokyo Yuta Nishina Research Core for Interdisciplinary Sciences, Okayama University Tsuyoshi Minami Institute of Industrial Science, The University of Tokyo We herein report an organic transistor functionalized with a phenylboronic acid derivative and graphene oxide for the quantification of plasma glucose levels, which has been achieved by the minimization of interferent effects derived from physical protein adsorption on the detection electrode. No potential conflict of interest relevant to this article was reported.

Public Library of Science Acta Medica Okayama 1932-6203 19 3 2024 Chemical range recognized by the ligand-binding domain in a representative amino acid-sensing taste receptor, T1r2a/T1r3, from medaka fish e0300981 EN Hikaru Ishida Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Norihisa Yasui Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Atsuko Yamashita Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Taste receptor type 1 (T1r) proteins are responsible for recognizing nutrient chemicals in foods. In humans, T1r2/T1r3 and T1r1/T1r3 heterodimers serve as the sweet and umami receptors that recognize sugars or amino acids and nucleotides, respectively. T1rs are conserved among vertebrates, and T1r2a/T1r3 from medaka fish is currently the only member for which the structure of the ligand-binding domain (LBD) has been solved. T1r2a/T1r3 is an amino acid receptor that recognizes various l-amino acids in its LBD as observed with other T1rs exhibiting broad substrate specificities. Nevertheless, the range of chemicals that are recognized by T1r2a/T1r3LBD has not been extensively explored. In the present study, the binding of various chemicals to medaka T1r2a/T1r3LBD was analyzed. A binding assay for amino acid derivatives verified the specificity of this protein to l-alpha-amino acids and the importance of alpha-amino and carboxy groups for receptor recognition. The results further indicated the significance of the alpha-hydrogen for recognition as replacing it with a methyl group resulted in a substantially decreased affinity. The binding ability to the protein was not limited to proteinogenic amino acids, but also to non-proteinogenic amino acids, such as metabolic intermediates. Besides l-alpha-amino acids, no other chemicals showed significant binding to the protein. These results indicate that all of the common structural groups of alpha-amino acids and their geometry in the l-configuration are recognized by the protein, whereas a wide variety of alpha-substituents can be accommodated in the ligand binding sites of the LBDs. No potential conflict of interest relevant to this article was reported.

Nature Portfolio Acta Medica Okayama 2045-2322 14 1 2024 Development of a novel AAK1 inhibitor via Kinobeads-based screening 6723 EN Akari Yoshida 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 Fumiya Matsumoto Department of Science Education, Graduate School of Education, Okayama University Tomoyuki Miyagawa Department of Science Education, Graduate School of Education, Okayama University Rei Okino Department of Science Education, Graduate School of Education, Okayama University Yumeya Ikeda Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Natsume Tada Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Akira Gotoh 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 Naoya Hatano Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Ryo Morishita CellFree Sciences Co. Ltd Ayano Satoh Organelle Systems Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Yukinari Sunatsuki Graduate School of Natural Science and Technology, Okayama University Ulf J. Nilsson Department of Chemistry, Lund University Teruhiko Ishikawa Department of Science Education, Graduate School of Education, Okayama University Hiroshi Tokumitsu Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University A chemical proteomics approach using Ca2+/calmodulin-dependent protein kinase kinase (CaMKK) inhibitor-immobilized sepharose (TIM-063-Kinobeads) identified main targets such as CaMKK alpha/1 and beta/2, and potential off-target kinases, including AP2-associated protein kinase 1 (AAK1), as TIM-063 interactants. Because TIM-063 interacted with the AAK1 catalytic domain and inhibited its enzymatic activity moderately (IC50 = 8.51 mu M), we attempted to identify potential AAK1 inhibitors from TIM-063-derivatives and found a novel AAK1 inhibitor, TIM-098a (11-amino-2-hydroxy-7H-benzo[de]benzo[4,5]imidazo[2,1-a]isoquinolin-7-one) which is more potent (IC50 = 0.24 mu M) than TIM-063 without any inhibitory activity against CaMKK isoforms and a relative AAK1-selectivity among the Numb-associated kinases family. TIM-098a could inhibit AAK1 activity in transfected cultured cells (IC50 = 0.87 mu M), indicating cell-membrane permeability of the compound. Overexpression of AAK1 in HeLa cells significantly reduced the number of early endosomes, which was blocked by treatment with 10 mu M TIM-098a. These results indicate TIM-063-Kinobeads-based chemical proteomics is efficient for identifying off-target kinases and re-evaluating the kinase inhibitor (TIM-063), leading to the successful development of a novel inhibitory compound (TIM-098a) for AAK1, which could be a molecular probe for AAK1. TIM-098a may be a promising lead compound for a more potent, selective and therapeutically useful AAK1 inhibitor. No potential conflict of interest relevant to this article was reported.

AIP Publishing Acta Medica Okayama 0021-9606 160 9 2024 GenIce-core: Efficient algorithm for generation of hydrogen-disordered ice structures 094101 EN Masakazu Matsumoto Research Institute for Interdisciplinary Science, Okayama University Takuma Yagasaki Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University Hideki Tanaka Toyota Physical and Chemical Research Institute Ice is different from ordinary crystals because it contains randomness, which means that statistical treatment based on ensemble averaging is essential. Ice structures are constrained by topological rules known as the ice rules, which give them unique anomalous properties. These properties become more apparent when the system size is large. For this reason, there is a need to produce a large number of sufficiently large crystals that are homogeneously random and satisfy the ice rules. We have developed an algorithm to quickly generate ice structures containing ions and defects. This algorithm is provided as an independent software module that can be incorporated into crystal structure generation software. By doing so, it becomes possible to simulate ice crystals on a previously impossible scale. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0743-7463 40 15 2024 Engineering Interconnected Open-Porous Particles via Microfluidics Using Bijel Droplets as Structural Templates 8074 8082 EN Mina Masaoka Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Hiroaki Ishida Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Takaichi Watanabe Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Tsutomu Ono Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Designing porous structures is key in materials science, particularly for separation, catalysis, and cell culture systems. Bicontinuous interfacially jammed emulsion gels represent a unique class of soft matter formed by kinetically arresting the separation of the spinodal decomposition phase, which is stabilized by colloidal particles with neutral wetting. This study introduces a microfluidic technique to create highly interconnected open-porous particles using bijel droplets stabilized with hexadecyltrimethylammonium bromide (CTAB)-modified silica particles. Monodisperse droplets comprising a hydrophobic monomer, water, ethanol, silica particles, and CTAB were initially formed in the microfluidic device. The diffusion of ethanol from these droplets into the continuous cyclohexane phase triggered spinodal decomposition within the droplets. The phase-separated structure within the droplets was stabilized by the CTAB-modified silica particles, and subsequent photopolymerization yielded microparticles with highly interconnected, open pores. Moreover, the influence of the ratio of the CTAB and silica particles, fluid composition, and microchannel direction on the final structure of the microparticles was explored. Our findings indicated that the phase-separated structure of the particles transitioned from oil-in-water to water-in-oil as the CTAB/silica ratio was increased. At intermediate CTAB/silica ratios, microparticles with bicontinuous structures were formed. Regardless of the fluid composition, the pore size of the particles increased with time after phase separation. However, this coarsening was arrested 15 s after droplet formation in the CTAB-modified silica particles, accompanied by a change in the particle shape from spherical to ellipsoidal. In situ observations of the bijel droplet formation revealed that the particle shape deformation is caused by the rolling of elastic bijel droplets at the bottom of the microchannel. As such, the channel setup was altered from horizontal to vertical to prevent the deformation of bijel droplets, resulting in spherical particles with open pores. No potential conflict of interest relevant to this article was reported.

岡山大学理学部地球科学科 Acta Medica Okayama 1340-7414 30 1 2024 鳶尾塚古墳の石室石材の岩石学的特徴 1 12 EN Takahiro KANEKO Department of Earth Sciences, Okayama University Toshio NOZAKA Department of Earth Sciences, Okayama University Akira SEIKE Department of Archaeology, Okayama University 10.18926/ESR/66844 　Tobiotsuka Kofun, a tumulus built on the Misu Hills in the Kofun period, has a horizontal stone chamber made of huge stone blocks with a width up to 2 meters or more. To specify the source of the stone blocks, we carried out the measurement of magnetic susceptibility, petrographic observation, and chemical analysis of minerals. The stones are amphibole-biotite granite with phenocrystic large grains of K-feldspar. The back-wall stone of the chamber has higher magnetic susceptibility than ceiling and side-wall stones, which probably results from a higher amount of magnetite formed by the alteration of biotite in the back-wall stone. Furthermore, the back-wall stone is different from ceiling stone in that it has lower XMg [Mg/(Mg + Fe) mole ratio], lower Al, Ti, and Na + K contents and higher Si contents of amphibole, higher XMg of biotite, and shows a tendency to have higher Na (albite component) contents at rims of plagioclase crystals and lower Ti contents of zircon. These characteristics of the back-wall stone are similar to those of granite exposed in the Koshinzan area about 2 km northeast of Tobiotsuka Kofun, whereas the ceiling and side-wall stones are similar to granite outcrops in the vicinity of Tobiotsuka Kofun, e.g., in the Midoriyama area. It is concluded that the quarry for the back-wall was located at a different place from that for the ceiling and side-wall stones. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 78 1 2024 Quantitative Assessment of the Heat Transfer Capacity of Ice Bags and their Cooling Effects on the Skin Surface and Core Temperature 53 61 EN Yukiko Ichikawa Department of Nursing Science, Faculty of Health and Welfare Science, Okayama Prefectural University Tetsuya Ogino Department of Nursing Science, Faculty of Health and Welfare Science, Okayama Prefectural University Original Article 10.18926/AMO/66671 Ice bags are frequently used in medical care settings for pain relief, comfort, and in some cases, whole-body cooling. This study quantifies heat energy transfer capacity of ice bags and evaluates their cooling effects on body temperature. Forty-eight healthy adults in their 20s were recruited. An ice bag wrapped in two layers of dry towel was applied to the forehead, neck, or palm of each participant for 10 min. The skin surface temperature, heat flow, and core temperature were recorded during the cooling and non-cooling periods, with energy transfer calculated by integrating heat flow over time. Over the non-cooling period, 31.4-53.6 kJ·m-2 of energy was dissipated over 10 min, whereas during the cooling period, the range increased to 180.0-218.7 kJ·m-2 over 10 min. Skin surface temperature decreased by 3.2-5.7°C, whereas core temperature was unchanged. Ice bag use augmented energy transfer by about 150-180 kJ·m-2 over 10 min, but this was insufficient for rapid whole body cooling due to the small skin-surface area in contact with the ice bag. The measured energy transfer indicated that topical ice bag application absorbs insufficient energy to affect core temperature. Quantitative assessment of energy transfer was shown to inform the safe and appropriate use of thermotherapy. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1936-0851 18 6 2024 Spatially Uniform and Quantitative Surface-Enhanced Raman Scattering under Modal Ultrastrong Coupling Beyond Nanostructure Homogeneity Limits 4993 5002 EN Yoshiki Suganami Research Institute for Electronic Science, Hokkaido University Tomoya Oshikiri Research Institute for Electronic Science, Hokkaido University Hideyuki Mitomo Research Institute for Electronic Science, Hokkaido University Keiji Sasaki Research Institute for Electronic Science, Hokkaido University Yen-En Liu Research Institute for Electronic Science, Hokkaido University Xu Shi Creative Research Institution, Hokkaido University Yasutaka Matsuo Research Institute for Electronic Science, Hokkaido University Kuniharu Ijiro Research Institute for Electronic Science, Hokkaido University Hiroaki Misawa Research Institute for Interdisciplinary Science, Okayama University We developed a substrate that enables highly sensitive and spatially uniform surface-enhanced Raman scattering (SERS). This substrate comprises densely packed gold nanoparticles (d-AuNPs)/titanium dioxide/Au film (d-ATA). The d-ATA substrate demonstrates modal ultrastrong coupling between localized surface plasmon resonances (LSPRs) of AuNPs and Fabry–Pérot nanocavities. d-ATA exhibits a significant enhancement of the near-field intensity, resulting in a 78-fold increase in the SERS signal for crystal violet (CV) compared to that of d-AuNP/TiO2 substrates. Importantly, high sensitivity and a spatially uniform signal intensity can be obtained without precise control of the shape and arrangement of the nanoscale AuNPs, enabling quantitative SERS measurements. Additionally, SERS measurements of rhodamine 6G (R6G) on this substrate under ultralow adsorption conditions (0.6 R6G molecules/AuNP) show a spatial variation in the signal intensity within 3%. These findings suggest that the SERS signal under modal ultrastrong coupling originates from multiple plasmonic particles with quantum coherence. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1744-683X 20 7 2024 Controlled mechanical properties of poly(ionic liquid)-based hydrophobic ion gels by the introduction of alumina nanoparticles with different shapes 1611 1619 EN Yuna Mizutani Department of Applied Chemistry, Graduate School of Natural Science, Okayama University Takaichi Watanabe Department of Applied Chemistry, Graduate School of Natural Science, Okayama University Carlos G. Lopez Department of Materials Science and Engineering, The Pennsylvania State University Tsutomu Ono Department of Applied Chemistry, Graduate School of Natural Science, Okayama University Ionic–liquid gels, also known as ion gels, have gained considerable attention due to their high ionic conductivity and CO2 absorption capacity. However, their low mechanical strength has hindered their practical applications. A potential solution to this challenge is the incorporation of particles, such as silica nanoparticles, TiO2 nanoparticles, and metal–organic frameworks (MOFs) into ion gels. Comparative studies on the effect of particles with different shapes are still in progress. This study investigated the effect of the shape of particles introduced into ion gels on their mechanical properties. Consequently, alumina/poly(ionic liquid) (PIL) double-network (DN) ion gels consisting of clustered alumina nanoparticles with various shapes (either spherical or rod-shaped) and a chemically crosslinked poly[1-ethyl-3-vinylimidazolium bis(trifluoromethanesulfonyl)imide] (PC2im-TFSI, PIL) network were prepared. The results revealed that the mechanical strengths of the alumina/PIL DN ion gels were superior to those of PIL single-network ion gels without particles. Notably, the fracture energies of the rod-shaped alumina/PIL DN ion gels were approximately 2.6 times higher than those of the spherical alumina/PIL DN ion gels. Cyclic tensile tests were performed, and the results indicate that the loading energy on the ion gel was dissipated through the fracture of the alumina network. TEM observation suggests that the variation in the mechanical strength depending on the shape can be attributed to differences in the aggregation structure of the alumina particles, thus indicating the possibility of tuning the mechanical strength of ion gels by altering not only particle kinds but its shape. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1549-9596 64 2 2023 pSPICA Force Field Extended for Proteins and Peptides 532 542 EN Yusuke Miyazaki Research Institute for Interdisciplinary Science, Okayama University Wataru Shinoda Research Institute for Interdisciplinary Science, Okayama University Many coarse-grained (CG) molecular dynamics (MD) studies have been performed to investigate biological processes involving proteins and lipids. CG force fields (FFs) in these MD studies often use implicit or nonpolar water models to reduce computational costs. CG-MD using water models cannot properly describe electrostatic screening effects owing to the hydration of ionic segments and thus cannot appropriately describe molecular events involving water channels and pores through lipid membranes. To overcome this issue, we developed a protein model in the pSPICA FF, in which a polar CG water model showing the proper dielectric response was adopted. The developed CG model greatly improved the transfer free energy profiles of charged side chain analogues across the lipid membrane. Application studies on melittin-induced membrane pores and mechanosensitive channels in lipid membranes demonstrated that CG-MDs using the pSPICA FF correctly reproduced the structure and stability of the pores and channels. Furthermore, the adsorption behavior of the highly charged nona-arginine peptides on lipid membranes changed with salt concentration, indicating the pSPICA FF is also useful for simulating protein adsorption on membrane surfaces. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1936-0851 18 1 2023 Close-Packed Ices in Nanopores 347 354 EN Kenji Mochizuki Department of Chemistry, Zhejiang University Yuji Adachi Graduate School of Natural Sciences, Okayama University Kenichiro Koga Department of Chemistry, Okayama University Water molecules in any of the ice polymorphs organize themselves into a perfect four-coordinated hydrogen-bond network at the expense of dense packing. Even at high pressures, there seems to be no way to reconcile the ice rules with the close packing. Here, we report several close-packed ice phases in carbon nanotubes obtained from molecular dynamics simulations of two different water models. Typically they are in plastic states at high temperatures and are transformed into the hydrogen-ordered ice, keeping their close-packed structures at lower temperatures. The close-packed structures of water molecules in carbon nanotubes are identified with those of spheres in a cylinder. We present design principles of hydrogen-ordered, close-packed structures of ice in nanotubes, which suggest many possible dense ice forms with or without nonzero polarization. In fact, some of the simulated ices are found to exhibit ferroelectric ordering upon cooling. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 1341-321X 30 3 2024 Relevance of complement immunity with brain fog in patients with long COVID 236 241 EN Hideharu Hagiya Department of Infectious Diseases, Okayama University Hospital Kazuki Tokumasu Department of General Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yuki Otsuka Department of General Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Naruhiko Sunada Department of General Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yasuhiro Nakano Department of General Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroyuki Honda Department of General Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masanori Furukawa Clinical Laboratory, Okayama University Hospital Fumio Otsuka Department of General Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Introduction<br> This study aimed to elucidate the prevalence and clinical characteristics of patients with long COVID (coronavirus disease 2019), especially focusing on 50% hemolytic complement activity (CH50).<br> <br> Methods<br> This retrospective observational study focused on patients who visited Okayama University Hospital (Japan) for the treatment of long COVID between February 2021 and March 2023. CH50 levels were measured using liposome immunometric assay (Autokit CH50 Assay, FUJIFILM Wako Pure Chemical Corporation, Japan); high CH50 was defined as ≥59 U/mL. Univariate analyses assessed differences in the clinical background, long COVID symptoms, inflammatory markers, and clinical scores of patients with normal and high CH50. Logistic regression model investigated the association between high CH50 levels and these factors.<br> <br> Results<br> Of 659 patients who visited our hospital, 478 patients were included. Of these, 284 (59.4%) patients had high CH50 levels. Poor concentration was significantly more frequent in the high CH50 group (7.2% vs. 13.7%), whereas no differences were observed in other subjective symptoms (fatigue, headache, insomnia, dyspnea, tiredness, and brain fog). Multivariate analysis was performed on factors that could be associated with poor concentration, suggesting a significant relationship to high CH50 levels (adjusted odds ratio [aOR], 2.70; 95% confidence interval [CI], 1.33–5.49). Also, high CH50 was significantly associated with brain fog (aOR, 1.66; 95% CI, 1.04–2.66).<br> <br> Conclusions<br> High CH50 levels were frequently reported in individuals with long COVID, indicating a relationship with brain fog. Future in-depth research should examine the pathological role and causal link between complement immunity and the development of long COVID. No potential conflict of interest relevant to this article was reported.

Informa UK Limited Acta Medica Okayama 0737-3937 42 2 2023 Flavor retention characteristics of amorphous solid dispersion of flavors, prepared by vacuum-foam- and spray-drying under different conditions 227 237 EN Yuna Nitta Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Haruna Sato Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Rina Yamamoto Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Hiroyuki Imanaka Department of Applied Chemistry, 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 Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University We investigated the powderization of flavoring substances, using an amorphous solid dispersion (ASD) technique, in which hydrophobic molecules are separately embedded in a water-soluble carrier matrix. Six flavors, five carrier forming materials (polyvinylpyrrolidone/disaccharides), two solvents (methanol/ethanol) and two drying methods (vacuum-foam-/spray-drying) were employed. The drying conditions for the two drying processes were first examined, and under the optimal drying conditions, various flavor-carrier combinations and compositions of ASD samples were prepared and their flavor retention after drying and during storage under a vacuum were compared. Results demonstrated that flavor loss during drying and storage was minimized when the material was vacuum-foam-dried with polyvinylpyrrolidone. Vacuum-foam-drying in the presence of α-maltose or palatinose also resulted in a greater retention of flavor during drying and storage than a typical O/W emulsification-based powderization. These findings suggest that the ASD-based powderization of flavoring materials is a feasible alternative to the currently used produces. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0743-7463 39 44 2023 Analysis of Evaporation of Droplet Pairs by a Quasi-Steady-State Diffusion Model Coupled with the Evaporative Cooling Effect 15587 15596 EN Yutaka Yamada Faculty of Environmental, Life, Natural Science and Technology, Okayama University Kazuma Isobe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Akihiko Horibe Faculty of Environmental, Life, Natural Science and Technology, Okayama University Multidroplet evaporation is a common phase-change phenomenon not only in nature but also in many industrial applications, including inkjet printing and spray cooling. The evaporation behavior of these droplets is strongly affected by the distance between neighboring droplets, and in particular, evaporation suppression occurs as the distance decreases. However, further quantitative information, such as the temperature and local evaporation flux, is limited because the analytical models of multidroplet evaporation only treat vapor diffusion, and the effect of the latent heat transfer through the liquid–vapor phase change is ignored. Here, we perform a numerical analysis of evaporating droplet pairs that linked vapor diffusion from the droplet surface and evaporative cooling. Heat transfer through the liquid and gas phases is also considered because the saturation pressure depends on the temperature. The results show an increase in the vapor concentration in the region between the two droplets. Consequently, the local evaporation flux in the proximate region significantly decreases with decreasing separation distance. This means that the latent heat transfer through the phase change is diminished, and an asymmetrical temperature distribution occurs in the liquid and gas phases. These numerical results provide quantitative information about the temperature and local evaporation flux of evaporating droplet pairs, and they will guide further investigation of multiple droplet evaporation. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1463-9076 25 45 2023 Solvation free energies of alcohols in water: temperature and pressure dependences 31107 31117 EN Aoi Taira Department of Chemistry, Faculty of Science, Okayama University Ryuichi Okamoto Graduate School of Information Science, University of Hyogo Tomonari Sumi Department of Chemistry, Faculty of Science, Okayama University Kenichiro Koga Department of Chemistry, Faculty of Science, Okayama University Solvation free energies μ* of amphiphilic species, methanol and 1,2-hexanediol, are obtained as a function of temperature or pressure based on molecular dynamics simulations combined with efficient free-energy calculation methods. In general, μ* of an amphiphile can be divided into Image ID:d3cp03799a-t1.gif and Image ID:d3cp03799a-t2.gif, the nonpolar and electrostatic contributions, and the former is further divided into Image ID:d3cp03799a-t3.gif and Image ID:d3cp03799a-t4.gif which are the work of cavity formation process and the free energy change due to weak, attractive interactions between the solute molecule and surrounding solvent molecules. We demonstrate that μ* of the two amphiphilic solutes can be obtained accurately using a perturbation combining method, which relies on the exact expressions for Image ID:d3cp03799a-t5.gif and Image ID:d3cp03799a-t6.gif and requires no simulations of intermediate systems between the solute with strong, repulsive interactions and the solute with the van der Waals and electrostatic interactions. The decomposition of μ* gives us several physical insights including that μ* is an increasing function of T due to Image ID:d3cp03799a-t7.gif, that the contributions of hydrophilic groups to the temperature dependence of μ* are additive, and that the contribution of the van der Waals attraction to the solvation volume is greater than that of the electrostatic interactions. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1434-193X 26 47 2023 Electrochemical Coupling Reactions Using Non‐Transition Metal Mediators: Recent Advances e202300835 EN Koichi Mitsudo Division of Applied Chemistry Graduate School of Environmental Life, Natural Science and Technology, Okayama University 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 Seiji Suga Division of Applied Chemistry Graduate School of Environmental Life, Natural Science and Technology, Okayama University Indirect electrolysis method using appropriate mediators enables numerous chemical reactions. The general principles of mediators were described herein with a particular focus on non-transition metal mediators. Recent representative examples of bond formation reactions by indirect electrolysis are summarized and discussed here. No potential conflict of interest relevant to this article was reported.

AIP Publishing Acta Medica Okayama 1932-1058 17 5 2023 Diamond quantum sensors in microfluidics technology 054107 EN Masazumi Fujiwara Department of Chemistry, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University Diamond quantum sensing is an emerging technology for probing multiple physico-chemical parameters in the nano- to micro-scale dimensions within diverse chemical and biological contexts. Integrating these sensors into microfluidic devices enables the precise quantification and analysis of small sample volumes in microscale channels. In this Perspective, we present recent advancements in the integration of diamond quantum sensors with microfluidic devices and explore their prospects with a focus on forthcoming technological developments. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry Acta Medica Okayama 2041-6520 14 42 2023 An emissive charge-transfer excited-state at the well-defined hetero-nanostructure interface of an organic conjugated molecule and two-dimensional inorganic nanosheet 11914 11923 EN Tomokazu Umeyama Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo Daizu Mizutani Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Yuki Ikeda Department of Molecular Engineering, Graduate School of Engineering, Kyoto University W. Ryan Osterloh Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Futa Yamamoto Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo Kosaku Kato Graduate School of Natural Science and Technology, Okayama University Akira Yamakata Graduate School of Natural Science and Technology, Okayama University Masahiro Higashi Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Takumi Urakami Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Hirofumi Sato Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Hiroshi Imahori Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Precise engineering of excited-state interactions between an organic conjugated molecule and a two-dimensional semiconducting inorganic nanosheet, specifically the manipulation of charge-transfer excited (CTE) states, still remains a challenge for state-of-the-art photochemistry. Herein, we report a long-lived, highly emissive CTE state at structurally well-defined hetero-nanostructure interfaces of photoactive pyrene and two-dimensional MoS2 nanosheets via an N-benzylsuccinimide bridge (Py-Bn-MoS2). Spectroscopic measurements reveal that no charge-transfer state is formed in the ground state, but the locally-excited (LE) state of pyrene in Py-Bn-MoS2 efficiently generates an unusual emissive CTE state. Theoretical studies elucidate the interaction of MoS2 vacant orbitals with the pyrene LE state to form a CTE state that shows a distinct solvent dependence of the emission energy. This is the first example of organic-inorganic 2D hetero-nanostructures displaying mixed luminescence properties by an accurate design of the bridge structure, and therefore represents an important step in their applications for energy conversion and optoelectronic devices and sensors. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0022-2623 65 8 2022 Identification of a Vitamin-D Receptor Antagonist, MeTC7, which Inhibits the Growth of Xenograft and Transgenic Tumors In Vivo 6039 6055 EN Negar Khazan Wilmot Cancer Institute and Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Rochester Medical Center Kyu Kwang Kim Wilmot Cancer Institute and Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Rochester Medical Center Jeanne N. Hansen Department of Pediatrics, University of Rochester Medical Center Niloy A. Singh Wilmot Cancer Institute and Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Rochester Medical Center Taylor Moore Wilmot Cancer Institute and Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Rochester Medical Center Cameron W. A. Snyder Wilmot Cancer Institute and Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Rochester Medical Center Ravina Pandita Wilmot Cancer Institute and Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Rochester Medical Center Myla Strawderman Department of Biostatistics and Computational Biology, University of Rochester Medical Center Michiko Fujihara Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yuta Takamura Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Ye Jian Division of Surgery and of Microbiology and Immunology, University of Rochester Medical Center Nicholas Battaglia Division of Surgery and of Microbiology and Immunology, University of Rochester Medical Center Naohiro Yano Department of Surgery, Division of Surgical Research, Rhode Island Hospital, Alpert Medical School of Brown University Yuki Teramoto Department of Pathology and Laboratory Medicine, University of Rochester Medical Center Leggy A. Arnold Department of Chemistry and Biochemistry, University of Wisconsin Milwaukee Russell Hopson Department of Chemistry, Brown University Keshav Kishor Department of Chemistry, Birla Institute of Technology Sneha Nayak Department of Chemistry, Birla Institute of Technology Debasmita Ojha Department of Chemistry, Birla Institute of Technology Ashoke Sharon Department of Chemistry, Birla Institute of Technology John M. Ashton Genomics Core Facility, Wilmot Cancer Center, University of Rochester Medical Center Jian Wang Department of Pharmacology and Department of Biochemistry and Molecular Biology, Penn State College of Medicine, Penn State University Michael T. Milano Department of Radiation Oncology, University of Rochester Medical Center Hiroshi Miyamoto Department of Pathology and Laboratory Medicine, University of Rochester Medical Center David C. Linehan Division of Surgery and of Microbiology and Immunology, University of Rochester Medical Center Scott A. Gerber Division of Surgery and of Microbiology and Immunology, University of Rochester Medical Center Nada Kawar Center for Breast Health and Gynecologic Oncology, Mercy Medical Center Ajay P. Singh Rutgers, The State University of New Jersey Erdem D. Tabdanov CytoMechanobiology Laboratory, Department of Pharmacology, Penn State College of Medicine, Pennsylvania State University Nikolay V. Dokholyan Department of Pharmacology and Department of Biochemistry and Molecular Biology, Penn State College of Medicine, Penn State University Hiroki Kakuta Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Peter W. Jurutka School of Mathematical and Natural Sciences, Arizona State University, Health Futures Center Nina F. Schor Departments of Pediatrics, Neurology, and Neuroscience, University of Rochester Medical Center Rachael B. Rowswell-Turner Wilmot Cancer Institute and Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Rochester Medical Center Rakesh K. Singh Wilmot Cancer Institute and Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Rochester Medical Center Richard G. Moore Wilmot Cancer Institute and Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Rochester Medical Center Vitamin-D receptor (VDR) mRNA is overexpressed in neuroblastoma and carcinomas of lung, pancreas, and ovaries and predicts poor prognoses. VDR antagonists may be able to inhibit tumors that overexpress VDR. However, the current antagonists are arduous to synthesize and are only partial antagonists, limiting their use. Here, we show that the VDR antagonist MeTC7 (5), which can be synthesized from 7-dehydrocholesterol (6) in two steps, inhibits VDR selectively, suppresses the viability of cancer cell-lines, and reduces the growth of the spontaneous transgenic TH-MYCN neuroblastoma and xenografts in vivo. The VDR selectivity of 5 against RXRα and PPAR-γ was confirmed, and docking studies using VDR-LBD indicated that 5 induces major changes in the binding motifs, which potentially result in VDR antagonistic effects. These data highlight the therapeutic benefits of targeting VDR for the treatment of malignancies and demonstrate the creation of selective VDR antagonists that are easy to synthesize. No potential conflict of interest relevant to this article was reported.

Spandidos Publications Acta Medica Okayama 2049-9434 16 1 2021 Evaluation of skin sensitization based on interleukin‑2 promoter activation in Jurkat cells 3 EN Taichi Nagahata Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Yoshio Tsujino Graduate School of Science, Technology and Innovation, Kobe University Eiji Takayama Department of Oral Biochemistry, Asahi University School of Dentistry Haruka Hikasa Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Ayano Satoh Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Skin sensitization is an allergic reaction caused by certain chemical substances, and is an important factor to be taken into consideration when evaluating the safety of numerous types of products. Although animal testing has long been used to evaluate skin sensitization, the recent trend to regulate such testing has led to the development and use of alternative methods. Skin sensitization reactions are summarized in the form of an adverse outcome pathway consisting of four key events (KE), including covalent binding to skin proteins (KE1), keratinocyte activation (KE2), and dendritic cell activation (KE3). Equivalent alternative methods have been developed for KE1 to KE3, but no valid alternative has yet been developed for the evaluation of KE4 and T‑cell activation. Current alternative methods rely on data from KE1 to KE3 to predict the effect of chemicals on skin sensitization. The addition of KE4 data is expected to improve the accuracy and reproducibility of such predictions. The aim of this study was to establish an assay to evaluate KE4 T‑cell activation to supplement data on skin sensitization related to KE4. To evaluate T‑cell activation, the Jurkat T‑cell line stably expressing luciferase downstream of the pro‑inflammatory cytokine interleukin‑2 promoter was used. After exposure to known skin sensitizing agents and control substances, luciferase activity measurements revealed that this assay was valid for evaluating skin sensitization. However, two skin sensitizers known to have immunosuppressive effects on T‑cells reacted negatively in this assay. The results revealed that this assay simultaneously allows for monitoring of the skin sensitization and immuno‑suppressiveness of chemical substances and supplements KE4 T‑cell activation data, and may thus contribute to reducing the use of animal experiments. No potential conflict of interest relevant to this article was reported.

Pharmaceutical Society of Japan Acta Medica Okayama 0009-2363 71 2 2023 Identification of a Functionally Efficient and Thermally Stable Outward Sodium-Pumping Rhodopsin (BeNaR) from a Thermophilic Bacterium 154 164 EN Marie Kurihara Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Vera Thiel Department of Biological Sciences, Tokyo Metropolitan University Hirona Takahashi Department of Chemistry, Graduate School of Science, Okayama University of Science Keiichi Kojima Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University David M. Ward Department of Land Resources and Environmental Sciences, Montana State University Donald A. Bryant Department of Biochemistry and Molecular Biology, The Pennsylvania State University Makoto Sakai Department of Chemistry, Graduate School of Science, Okayama University of Science Susumu Yoshizawa Atmosphere and Ocean Research Institute, The University of Tokyo Yuki Sudo Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Rhodopsins are transmembrane proteins with retinal chromophores that are involved in photo-energy conversion and photo-signal transduction in diverse organisms. In this study, we newly identified and characterized a rhodopsin from a thermophilic bacterium, Bellilinea sp. Recombinant Escherichia coli cells expressing the rhodopsin showed light-induced alkalization of the medium only in the presence of sodium ions (Na+), and the alkalization signal was enhanced by addition of a protonophore, indicating an outward Na+ pump function across the cellular membrane. Thus, we named the protein Bellilinea Na+-pumping rhodopsin, BeNaR. Of note, its Na+-pumping activity is significantly greater than that of the known Na+-pumping rhodopsin, KR2. We further characterized its photochemical properties as follows: (i) Visible spectroscopy and HPLC revealed that BeNaR has an absorption maximum at 524 nm with predominantly (>96%) the all-trans retinal conformer. (ii) Time-dependent thermal denaturation experiments revealed that BeNaR showed high thermal stability. (iii) The time-resolved flash-photolysis in the nanosecond to millisecond time domains revealed the presence of four kinetically distinctive photointermediates, K, L, M and O. (iv) Mutational analysis revealed that Asp101, which acts as a counterion, and Asp230 around the retinal were essential for the Na+-pumping activity. From the results, we propose a model for the outward Na+-pumping mechanism of BeNaR. The efficient Na+-pumping activity of BeNaR and its high stability make it a useful model both for ion transporters and optogenetics tools. No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 2694-2453 3 5 2023 Highly Stretchable Stress-Strain Sensor from Elastomer Nanocomposites with Movable Cross-links and Ketjenblack 394 405 EN Ryohei Ikura Department of Macromolecular Science, Graduate School of Science and Forefront Research Center for Fundamental Sciences, Osaka University Kota Kajimoto Department of Macromolecular Science, Graduate School of Science, Osaka University Junsu Park Department of Macromolecular Science, Graduate School of Science and Forefront Research Center for Fundamental Sciences, Osaka University Shunsuke Murayama Graduate School of Organic Materials Engineering, Yamagata University Yusei Fujiwara Department of Mechanical Engineering, Osaka Institute of Technology Motofumi Osaki Department of Macromolecular Science, Graduate School of Science and Forefront Research Center for Fundamental Sciences, Osaka University Tomohiro Suzuki Kanagawa Technical Center, Yushiro Chemical Industry Co., Ltd. Hidenori Shirakawa Kanagawa Technical Center, Yushiro Chemical Industry Co., Ltd. Yujiro Kitamura Kanagawa Technical Center, Yushiro Chemical Industry Co., Ltd. Hiroaki Takahashi Kanagawa Technical Center, Yushiro Chemical Industry Co., Ltd. Yasumasa Ohashi Kanagawa Technical Center, Yushiro Chemical Industry Co., Ltd. Seiji Obata Research Core for Interdisciplinary Sciences, Okayama University Akira Harada SANKEN (The Institute of Scientific and Industrial Research), Osaka University Yuka Ikemoto Japan Synchrotron Radiation Research Institute Yuta Nishina Research Core for Interdisciplinary Sciences, Okayama University Yasutomo Uetsuji Department of Mechanical Engineering, Osaka Institute of Technology Go Matsuba Graduate School of Organic Materials Engineering, Yamagata University Yoshinori Takashima Department of Macromolecular Science, Graduate School of Science and Forefront Research Center for Fundamental Sciences, Osaka University Practical applications like very thin stress-strain sensors require high strength, stretchability, and conductivity, simultaneously. One of the approaches is improving the toughness of the stress-strain sensing materials. Polymeric materials with movable cross-links in which the polymer chain penetrates the cavity of cyclodextrin (CD) demonstrate enhanced strength and stretchability, simultaneously. We designed two approaches that utilize elastomer nanocomposites with movable cross-links and carbon filler (ketjenblack, KB). One approach is mixing SC (a single movable cross-network material), a linear polymer (poly(ethyl acrylate), PEA), and KB to obtain their composite. The electrical resistance increases proportionally with tensile strain, leading to the application of this composite as a stress- strain sensor. The responses of this material are stable for over 100 loading and unloading cycles. The other approach is a composite made with KB and a movable cross-network elastomer for knitting dissimilar polymers (KP), where movable cross-links connect the CD-modified polystyrene (PSCD) and PEA. The obtained composite acts as a highly sensitive stress-strain sensor that exhibits an exponential increase in resistance with increasing tensile strain due to the polymer dethreading from the CD rings. The designed preparations of highly repeatable or highly responsive stress-strain sensors with good mechanical properties can help broaden their application in electrical devices. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 2046-2069 12 6 2022 Flame retardance-donated lignocellulose nanofibers (LCNFs) by the Mannich reaction with (amino-1,3,5-triazinyl)phosphoramidates and their properties 3300 3308 EN Fumiaki Ono Okayama Biomass Innovation Creative Center Takumi Okihara Graduate School of Natural Science and Technology, Okayama University Noboru Osaka Faculty of Science, Okayama University of Science Noriyuki Nagaoka Advanced Research Center for Oral and Craniofacial Science, Okayama University Dental School Yuji Kameoka Marubishi Oil Chemical Co., Ltd Akira Ishikawa Marubishi Oil Chemical Co., Ltd Hironari Ooki Gen Gen Corporation Takumi Ito Gen Gen Corporation Daisuke Todome Faculty of Science, Okayama University of Science Shinya Uemoto Okayama Biomass Innovation Creative Center Mitsuaki Furutani Okayama Biomass Innovation Creative Center Tsutomu Inokuchi Graduate School of Natural Science and Technology, Okayama University Kenji Okada Department of Life Science, Kurashiki University of Science & the Arts Nitrogen/phosphorus-containing melamines (NPCM), a durable flame-retardant, were prepared by the successive treatment of ArOH (Ar = BrnC6H5−n, n = 0, 1, 2, and 3) with POCl3 and melamine monomer. The prepared flame-retardants were grafted through the CH2 unit to lignocellulose nanofibers (LCNFs) by the Mannich reaction. The resulting three-component products were characterized using FT-IR (ATR) and EA. The thermal behavior of the NPCM-treated LCNF fabric samples was determined using TGA and DSC analyses, and their flammability resistances were evaluated by measuring their Limited Oxygen Index (LOI) and the UL-94V test. A multitude of flame retardant elements in the fabric samples increased the LOI values as much as 45 from 20 of the untreated LCNFs. Moreover, the morphology of both the NPCM-treated LCNFs and their burnt fabrics was studied with a scanning electron microscope (SEM). The heat release lowering effect of the LCNF fabric against the water-based paint was observed with a cone calorimeter. Furthermore, the mechanical properties represented as the tensile strength of the NPCM-treated LCNF fabrics revealed that the increase of the NPCM content in the PP-composites led to an increased bending strength with enhancing the flame-retardance. No potential conflict of interest relevant to this article was reported.

Japanese Society for Medical and Biological Engineering Acta Medica Okayama 2187-5219 11 2022 Skin Electrical Impedance Model for Evaluation of the Thickness and Water Content of the Stratum Corneum 98 108 EN Osamu Uehara Medical Engineering Laboratory, ALCARE CO., Ltd. Toshimasa Kusuhara Department of Radiological Technology, Graduate School of Health Sciences, Okayama University Kenichi Matsuzaki Medical Engineering Laboratory, ALCARE CO., Ltd. Yoshitake Yamamoto Okayama University Takao Nakamura Department of Radiological Technology, Graduate School of Health Sciences, Okayama University Deterioration of the skin barrier function causes symptoms such as allergies because various chemical substances may enter the human body. Quantitative evaluation of the thickness and water content of the stratum corneum is useful as a measure of the skin barrier function in domains such as dermatology, nursing science, and cosmetics development. The stratum corneum is responsible for most of the skin barrier function, and two factors—the thickness and water content of the stratum corneum—are thus important. In this paper, the stratum corneum is regarded as a parallel model of resistance and capacitance. From measurements of the electrical impedance of the skin, we propose a new model for simultaneous estimation of the thickness and water content of the stratum corneum conventionally measured by a confocal laser scanning microscope and a confocal Raman spectrometer, respectively, and we discuss the results of the measurements. The electrical impedance of the skin was measured using a device that we developed. The measurement began 3 seconds after the electrodes on the measurement head of the device came into contact with the skin, and parameters including the impedance, which was obtained by applying an alternating current signal at two frequencies, were measured. We measured the thickness and water content of the stratum corneum using confocal laser microscopy and confocal Raman spectroscopy, respectively; investigated the relationship of the thickness and water content of the stratum corneum with the electrical impedance of the skin; and established a new potential model for estimating the thickness and water content of the stratum corneum from the parallel resistance and capacitance. The correlation coefficients of the verification data were 0.931 and 0.776, respectively; and the root-mean-squared error of the thickness of the stratum corneum was 2.3 µm, while the root-mean-squared error of the water content at the surface of the stratum corneum was 5.4 points. These findings indicate the feasibility of quantitative evaluation of the thickness and water content of the stratum corneum by measuring skin electrical impedance. No potential conflict of interest relevant to this article was reported.

Nature Portfolio Acta Medica Okayama 2041-1723 14 1 2023 Pivotal role for S-nitrosylation of DNA methyltransferase 3B in epigenetic regulation of tumorigenesis 621 EN Kosaku Okuda Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Kengo Nakahara Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Akihiro Ito Chemical Genomics Research Group, RIKEN Center for Sustainable Resource Science Yuta Iijima Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Ryosuke Nomura Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Ashutosh Kumar Laboratory for Structural Bioinformatics, Center for Biosystems Dynamics Research, RIKEN Kana Fujikawa Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Kazuya Adachi Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Yuki Shimada Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Satoshi Fujio Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Reina Yamamoto Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Nobumasa Takasugi Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Kunishige Onuma Division of Experimental Pathology, Faculty of Medicine, Tottori University Mitsuhiko Osaki Division of Experimental Pathology, Faculty of Medicine, Tottori University Futoshi Okada Division of Experimental Pathology, Faculty of Medicine, Tottori University Taichi Ukegawa Department of Synthetic and Medicinal Chemistry, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Yasuo Takeuchi Department of Synthetic and Medicinal Chemistry, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Norihisa Yasui Laboratory of Structural Biology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Atsuko Yamashita Laboratory of Structural Biology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Hiroyuki Marusawa Department of Gastroenterology and Hepatology, Graduate School of Medicine, Kyoto University Yosuke Matsushita Division of Genome Medicine, Institute of Advanced Medical Sciences, Tokushima University Toyomasa Katagiri Division of Genome Medicine, Institute of Advanced Medical Sciences, Tokushima University Takahiro Shibata Graduate School of Bioagricultural Sciences, Nagoya University Koji Uchida Laboratory of Food Chemistry, Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo Sheng-Yong Niu Broad Institute of MIT and Harvard Nhi B. Lang Neurodegeneration New Medicines Center, and Departments of Molecular Medicine and Neuroscience, The Scripps Research Institute Tomohiro Nakamura Neurodegeneration New Medicines Center, and Departments of Molecular Medicine and Neuroscience, The Scripps Research Institute Kam Y. J. Zhang Laboratory for Structural Bioinformatics, Center for Biosystems Dynamics Research, RIKEN Stuart A. Lipton Neurodegeneration New Medicines Center, and Departments of Molecular Medicine and Neuroscience, The Scripps Research Institute Takashi Uehara Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University DNA methyltransferases (DNMTs) catalyze methylation at the C5 position of cytosine with S-adenosyl-l-methionine. Methylation regulates gene expression, serving a variety of physiological and pathophysiological roles. The chemical mechanisms regulating DNMT enzymatic activity, however, are not fully elucidated. Here, we show that protein S-nitrosylation of a cysteine residue in DNMT3B attenuates DNMT3B enzymatic activity and consequent aberrant upregulation of gene expression. These genes include Cyclin D2 (Ccnd2), which is required for neoplastic cell proliferation in some tumor types. In cell-based and in vivo cancer models, only DNMT3B enzymatic activity, and not DNMT1 or DNMT3A, affects Ccnd2 expression. Using structure-based virtual screening, we discovered chemical compounds that specifically inhibit S-nitrosylation without directly affecting DNMT3B enzymatic activity. The lead compound, designated DBIC, inhibits S-nitrosylation of DNMT3B at low concentrations (IC50 <= 100nM). Treatment with DBIC prevents nitric oxide (NO)-induced conversion of human colonic adenoma to adenocarcinoma in vitro. Additionally, in vivo treatment with DBIC strongly attenuates tumor development in a mouse model of carcinogenesis triggered by inflammation-induced generation of NO. Our results demonstrate that de novo DNA methylation mediated by DNMT3B is regulated by NO, and DBIC protects against tumor formation by preventing aberrant S-nitrosylation of DNMT3B. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0022-3263 88 14 2023 Oxytrofalcatin Puzzle: Total Synthesis and Structural Revision of Oxytrofalcatins B and C 9920 9926 EN Kazuma Sugitate Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiki Yamashiro Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ibuki Takahashi Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-tobetsu, Hokkaido 0610293, Japan Koji Yamada Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido Takumi Abe Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University The previously reported structures of oxytrofalcatins B and C possess a benzoyl indole core. However, following synthesis and NMR comparison of both the proposed structure and the synthesized oxazole, we have revised the structure of oxytrofalcatins B and C as oxazoles. The synthetic route developed herein can further our understanding of the biosynthetic pathways that govern the production of natural 2,5-diaryloxazoles. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1932-7447 127 28 2023 Lithium-Ion Dynamics in Sulfolane-Based Highly Concentrated Electrolytes 13837 13845 EN Shuhei Ikeda Department of Materials Chemistry, Nagoya University Seiji Tsuzuki Advanced Chemical Energy Research Centre (ACERC), Institute of Advanced Sciences, Yokohama National University Taku Sudoh Department of Chemistry and Life Science, Yokohama National University Keisuke Shigenobu Research Institute for Interdisciplinary Science, Okayama University Kazuhide Ueno Advanced Chemical Energy Research Centre (ACERC), Institute of Advanced Sciences, Yokohama National University Kaoru Dokko Advanced Chemical Energy Research Centre (ACERC), Institute of Advanced Sciences, Yokohama National University Masayoshi Watanabe Advanced Chemical Energy Research Centre (ACERC), Institute of Advanced Sciences, Yokohama National University Wataru Shinoda Research Institute for Interdisciplinary Science, Okayama University, Here, we report the use of molecular dynamics simulations with a polarizable force field to investigate Li-ion dynamics in sulfolane (SL)-based electrolytes. In SL-based highly concentrated electrolytes (HCEs) (e.g., SL/Li = 2:1), Li displays faster translational motion than other components, which should be related to the structural and dynamical properties of SL. In HCEs, a transient conduction network that penetrated the simulation system was always observed. Rapid (<1 ns) Li-ion hopping between adjacent coordination sites was observed throughout the network. Additionally, SLs rotated in the same timeframe without disrupting the conduction network. This rotation is believed to promote the hopping diffusion in the network. This was followed by a rotational relaxation of the SL dipole axis around the non-polar cyclohydrocarbon segment of SL (∼3.3 ns), which involves a reorganization of the network structure and an enhancement of the translational motion of the coordinating Li ions. The observed lifetime of Li–SL coordination was longer (>11 ns). Hence, it was concluded that the faster Li translational motion was obtained due to the faster rotational relaxation time of SL rather than the lifetime of Li–SL binding. The faster rotation of SL is related to its amphiphilic molecular structure with compact non-polar segments. Transport properties, such as the Onsager transport coefficients, ionic conductivity, and transference number under anion-blocking conditions, were also analyzed to characterize the features of the SL-based electrolyte. No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 2470-1343 8 12 2023 Development of Pipetteless Paper-Based Analytical Devices with a Volume Gauge 11213 11219 EN Kaewta Danchana Department of Chemistry, Okayama University Hiroshi Iwasaki Department of Chemistry, Okayama University Yada Thayawutthikun Flow Innovation-Research for Science and Technology Laboratories (FIRST Labs), Mahidol University Phoonthawee Saetear Flow Innovation-Research for Science and Technology Laboratories (FIRST Labs), Mahidol University Takashi Kaneta Department of Chemistry, Okayama University In this work, we propose a new design for paper based analytical devices (PADs) that eliminate the need to use a micropipette for sample introduction. With this design, a PAD is equipped with a distance-based detection channel that is connected to a storage channel that indicates the volume of a sample introduced into the PAD. The analyte in the sample solution reacts with a colorimetric reagent deposited into the distance-based detection channel as the sample solution flows into the storage channel where the volume is measured. The ratio of the lengths of the detection channel and that of the storage channel (D/S ratio) are constant for a sample containing a certain concentration, which is independent of the introduced volume. Therefore, the PADs permit volume-independent quantification using a dropper instead of a micropipette because the length of the storage channel plays the role of a volume gauge to estimate the introduced sample volume. In this study, the D/S ratios obtained with a dropper were comparable to those obtained with a micropipette, which confirmed that precise volume control is unnecessary for this PAD system. The proposed PADs were applied to the determinations of iron and bovine serum albumin using bathophenanthroline and tetrabromophenol blue as colorimetric reagents, respectively. The calibration curves showed good linear relationships with coefficients of 0.989 for iron and 0.994 for bovine serum albumin, respectively. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1359-7345 59 49 2023 Development of light-induced disruptive liposomes (LiDL) as a photoswitchable carrier for intracellular substance delivery 7591 7594 EN Taichi Tsuneishi Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Keiichi Kojima Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Fumika Kubota Faculty of Pharmaceutical Sciences, Hokkaido University Hideyoshi Harashima Faculty of Pharmaceutical Sciences, Hokkaido University Yuma Yamada Faculty of Pharmaceutical Sciences, Hokkaido University Yuki Sudo Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Light-driven inward proton pump rhodopsin RmXeR was embedded in pH-sensitive liposomes. Substance release from the proteoliposomes was observed following light illumination both in vitro and in cells, indicating the successful production of light-induced disruptive liposomes (LiDL). Thus, LiDL is a photoswitchable carrier utilized for intracellular substance delivery. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2023 Chemical reactions induced by localized light and their application to metal nanofabrication EN Yuki TAKEUCHI Graduate School of Natural Science and Technology, Okayama university No potential conflict of interest relevant to this article was reported.

BMC Acta Medica Okayama 1743-8977 20 1 2023 An investigation of the internal morphology of asbestos ferruginous bodies: constraining their role in the onset of malignant mesothelioma 19 EN Maya-Liliana Avramescu The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University Christian Potiszil The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University Tak Kunihiro The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University Kazunori Okabe Bell Land General Hospital Eizo Nakamura The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University Background　Asbestos is a fibrous mineral that was widely used in the past. However, asbestos inhalation is associated with an aggressive type of cancer known as malignant mesothelioma (MM). After inhalation, an iron-rich coat forms around the asbestos fibres, together the coat and fibre are termed an "asbestos ferruginous body" (AFB). AFBs are the main features associated with asbestos-induced MM. Whilst several studies have investigated the external morphology of AFBs, none have characterised the internal morphology. Here, cross-sections of multiple AFBs from two smokers and two non-smokers are compared to investigate the effects of smoking on the onset and growth of AFBs. Morphological and chemical observations of AFBs were undertaken by transmission electron microscopy, energy dispersive x-ray spectroscopy and selected area diffraction.<br> Results　The AFBs of all patients were composed of concentric layers of 2-line or 6-line ferrihydrite, with small spherical features being observed on the outside of the AFBs and within the cross-sections. The spherical components are of a similar size to Fe-rich inclusions found within macrophages from mice injected with asbestos fibres in a previous study. As such, the spherical components composing the AFBs may result from the deposition of Fe-rich inclusions during frustrated phagocytosis. The AFBs were also variable in terms of their Fe, P and Ca abundances, with some layers recording higher Fe concentrations (dense layers), whilst others lower Fe concentrations (porous layers). Furthermore, smokers were found to have smaller and overall denser AFBs than non-smokers.<br> Conclusions　The AFBs of smokers and non-smokers show differences in their morphology, indicating they grew in lung environments that experienced disparate conditions. Both the asbestos fibres of smokers and non-smokers were likely subjected to frustrated phagocytosis and accreted mucopolysaccharides, resulting in Fe accumulation and AFB formation. However, smokers' AFBs experienced a more uniform Fe-supply within the lung environment compared to non-smokers, likely due to Fe complexation from cigarette smoke, yielding denser, smaller and more Fe-rich AFBs. Moreover, the lack of any non-ferrihydrite Fe phases in the AFBs may indicate that the ferritin shell was intact, and that ROS may not be the main driver for the onset of MM. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0022-3093 592 2022 Effect of bond valence sum on the structural modeling of lead borate glass 121751 EN Masaaki Nagao Graduate School of Environmental and Life Science, Okayama University Shinichi Sakida Environmental Management Center, Okayama University Yasuhiko Benino Graduate School of Environmental and Life Science, Okayama University Tokuro Nanba Graduate School of Environmental and Life Science, Okayama University Atsushi Mukunoki JGC Japan Corporation Tamotsu Chiba JGC Japan Corporation Takahiro Kikuchi JGC Japan Corporation Tomofumi Sakuragi Radioactive Waste Management Funding and Research Center Hitoshi Owada Radioactive Waste Management Funding and Research Center The structural model of 66.7PbO-33.3B2O3 glass was constructed using a reverse Monte Carlo (RMC) method, in which bond valence sum (BVS) was added as a constraint condition to suppress formation of unrealistic local structures. Based on the crystal structures, the optimal BVS calculating conditions were determined. As a result, BVS distributions with small deviation were successfully achieved without lowering the reproducibility of other experimental constraints. The geometric asymmetry of PbOn polyhedra was evaluated from the eccentric distance between Pb and gravity center of oxygen atoms. The average eccentric distance was shorter than that in the lead borate crystals, indicating less asymmetry of PbOn units in the RMC glass model. The connectivity between BOn and PbOn units was investigated. It was consequently concluded that the glass had a different network structure from the crystal with the same composition, which might be due to the different chemical bonding character between the lead borate glasses and crystals. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1433-7851 62 21 2023 Bifunctional Iminophosphorane‐Catalyzed Enantioselective Nitroalkane Addition to Unactivated α,β‐Unsaturated Esters e202303391 EN Daniel Rozsar Department of Chemistry, University of Oxford, Chemistry Research Laboratory Alistair J. M. Farley Department of Chemistry, University of Oxford, Chemistry Research Laboratory Iain McLauchlan Department of Chemistry, University of Oxford, Chemistry Research Laboratory Benjamin D. A. Shennan Department of Chemistry, University of Oxford, Chemistry Research Laboratory Ken Yamazaki Division of Applied Chemistry, Okayama University Darren J. Dixon Department of Chemistry, University of Oxford, Chemistry Research Laboratory Herein we describe the enantioselective intermolecular conjugate addition of nitroalkanes to unactivated α,β-unsaturated esters, catalyzed by a bifunctional iminophosphorane (BIMP) superbase. The transformation provides the most direct access to pharmaceutically relevant enantioenriched γ-nitroesters, utilizing feedstock chemicals, with unprecedented selectivity. The methodology exhibits a broad substrate scope, including β-(fluoro)alkyl, aryl and heteroaryl substituted electrophiles, and was successfully applied on a gram scale with reduced catalyst loading, and, additionally, catalyst recovery was carried out. The formal synthesis of a range of drug molecules, and an enantioselective synthesis of (S)-rolipram were achieved. Additionally, computational studies revealed key reaction intermediates and transition state structures, and provided rationale for high enantioselectivities, in good agreement with experimental results. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0195-928X 44 5 2023 Synthesis and Characterization of Silica-Encapsulated n-Tetracosane and the Effect of Surface Modification by Silane Coupling Agents 69 EN Kyosuke Okuno Graduate School of Natural Science and Technology, Okayama University Kazuma Isobe Graduate School of Natural Science and Technology, Okayama University Akihiko Horibe Graduate School of Natural Science and Technology, Okayama University Yutaka Yamada Graduate School of Natural Science and Technology, Okayama University Microencapsulation of n-tetracosane, whose melting point is approximately 50 degrees C, in a silica shell has been performed through the sol-gel method using tetraethyl orthosilicate (TEOS) as the precursor for silica-shell formation. Additionally, two types of silane coupling agents were used to modify the surface of the microcapsules to change the wettability. The morphology of the microcapsules was observed by scanning electron microscopy. The chemical composition was characterized by Fourier transform infrared spectroscopy. The results confirmed the presence of n-tetracosane and silica in the synthesized microcapsules. Wettability analysis showed hydrophobic and hydrophilic features because of the added silane coupling agents. From the results of differential scanning calorimetry measurements, the encapsulation ratio of the microcapsules increased with decreasing TEOS/n-tetracosane ratio, and the highest encapsulation ratio was 87.1 % at a TEOS/n-tetracosane ratio of 0.25. The pH in the microcapsule solution was affected by addition of a silane coupling agent, and shifting the pH to the basic side lowered the encapsulation ratio owing to enhancement of silica condensation. After 100 differential scanning calorimetry cycles, there was no significant degradation in the phase-change temperatures and enthalpies, which confirmed the good phase-change stability and repeatability. Therefore, the microcapsules are a potential material for thermal-energy-storage systems to effectively utilize energy. No potential conflict of interest relevant to this article was reported.

eLife Sciences Publications Ltd. Acta Medica Okayama 2050-084X 12 2023 Chloride ions evoke taste sensations by binding to the extracellular ligand-binding domain of sweet/umami taste receptors e84291 EN Nanako Atsumi Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Keiko Yasumatsu Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuriko Takashina School of Pharmaceutical Sciences, Okayama University Chiaki Ito Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Norihisa Yasui Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Robert F. Margolskee Monell Chemical Senses Center Atsuko Yamashita Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Salt taste sensation is multifaceted: NaCl at low or high concentrations is preferably or aversively perceived through distinct pathways. Cl- is thought to participate in taste sensation through an unknown mechanism. Here, we describe Cl- ion binding and the response of taste receptor type 1 (T1r), a receptor family composing sweet/umami receptors. The T1r2a/T1r3 heterodimer from the medaka fish, currently the sole T1r amenable to structural analyses, exhibited a specific Cl- binding in the vicinity of the amino-acid-binding site in the ligand-binding domain (LBD) of T1r3, which is likely conserved across species, including human T1r3. The Cl- binding induced a conformational change in T1r2a/T1r3LBD at sub- to low-mM concentrations, similar to canonical taste substances. Furthermore, oral Cl- application to mice increased impulse frequencies of taste nerves connected to T1r-expressing taste cells and promoted their behavioral preferences attenuated by a T1r-specific blocker or T1r3 knock-out. These results suggest that the Cl- evokes taste sensations by binding to T1r, thereby serving as another preferred salt taste pathway at a low concentration. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1932-7447 127 5 2023 Uniform Formation of a Characteristic Nanocomposite Structure of Biogenous Iron Oxide for High Rate Performance as the Anode of Lithium-Ion Batteries 2223 2230 EN Masakuni Takahashi Graduate School of Natural Science and Technology, Okayama University Ryo Sakuma Graduate School of Natural Science and Technology, Okayama University Hideki Hashimoto Graduate School of Natural Science and Technology, Okayama University Tatsuo Fujii Graduate School of Natural Science and Technology, Okayama University Jun Takada Graduate School of Natural Science and Technology, Okayama University Recently, Fe2O3 has been considered as an alternative anode material for lithium-ion batteries (LIBs) owing to its high theoretical capacity (approximately 1000 mA h g-1), low cost, and nontoxicity. However, its rate performance remains poor relative to that of the conventional graphite anode. In this study, Fe2O3-based anodes were prepared through the annealing of biogenous Fe2O3 (L-BIOX) samples produced by an aquatic Fe-oxidizing bacterium. The effect of the annealing temperature on the performance of the synthesized Fe2O3-based material as the anode of an LIB was investigated. Electrochemical measurements revealed that the annealed L-BIOX samples at 300-700 degrees C exhibited higher rate performances than the unannealed material. Particularly, the sample annealed at 700 degrees C exhibited the highest capacity among the synthesized materials and showed a higher performance than the previously reported Fe2O3-based anodes. It exhibited a capacity of 923 mA h g-1 even at a high current density of 2 A g-1. After annealing at 700 degrees C and discharging, the synthesized biogenous material had a uniform nanocomposite structure composed of alpha-Fe2O3 nanoparticles dispersed in an amorphous matrix of Li-Si-P oxide. To form this uniform nanostructure, the solid-state diffusion resistance of the Li+ ions in the active material was reduced, which consequently improved the rate performance of the electrode. Therefore, this study provides substantial insights into the development and improvement of the performance of novel Fe2O3-based nanomaterials as the anode of LIBs. No potential conflict of interest relevant to this article was reported.

岡山大学全学教育・ 学生支援機構 Acta Medica Okayama 2432-9665 7 2023 Learning in seismic time: Japanese and Chilean education in the Anthropocene 16 24 EN Dong Kwang Kim Okayama University Peodair Leih Universidad Andres Bello Ian Teo Australian Council for Educational Research Brigid Freeman University of Melbourne 10.18926/64994 Scientific consensus agrees that over recent decades and generations, Earth has entered a new geological epoch, termed the Anthropocene. Whereas previous new epochs are postulated to have followed comet strikes and solar realignment, it is demonstrable that it is now human activity that most affects climate change, the release and transformation of chemicals, and general endangerment to life forms. At the same time, human societies throughout history can be seen to have adjusted to effects beyond their control. This is particularly clear in countries marked by frequent seismic activity, with Japan and Chile being prime examples. Particularly, changes in educational policy over the last hundred years appear to correlate to responses to major seismic catastrophes in these countries, with this article proposing to supplement understandings of educational policy evolution with consideration of the legacies of such cataclysms and the revised priorities they elicit. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2076-3417 12 3 2022 Reconditioning of Diamond Coated Tools and Its Impact on Cutting Performance for CFRP Laminates 1288 EN Alexander Soldatov Graduate School of Natural Science and Technology, Okayama University Alexey Remnev ITAC Ltd., Group of ShinMaywa Industries Akira Okada Graduate School of Natural Science and Technology, Okayama University In recent years, CVD diamond-coated tungsten carbide (WC-Co) tools have been widely utilized due to their benefits in the machining of non-ferrous alloys and polymer composite materials, especially carbon-fiber-reinforced plastics (CFRPs). The reconditioning of such coated tools is economically attractive due to their high cost and short tool life. The decoating of the remaining diamond film from the used tools and the subsequent surface preparation by wet chemical pretreatment are essential steps for new CVD diamond film formation. Previously, it was shown that reactive ion beam etching (RIBE) could effectively remove CVD diamond films. However, some degree of WC-Co tool substrate damage is expected due to the high ion energy in RIBE and the chemical activity in wet etching. This study addresses the effects of RIBE decoating and surface pretreatment steps on WC-Co tools with a complex shape in terms of the ion-induced surface damage, geometry alteration, and adhesion of a subsequently re-applied CVD diamond film. Moreover, the cutting performance of the tools subjected to the RIBE decoating and repeated film deposition was studied via CFRP cutting tests. It has been shown that the RIBE decoated and recoated tools had a high level of cutting performance comparable to the new tools. No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 2470-1343 8 2023 Detection of Membrane Potential-Dependent Rhodopsin Fluorescence Using Low-Intensity Light Emitting Diode for Long-Term Imaging 4826 4834 EN Shiho Kawanishi Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Keiichi Kojima Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Atsushi Shibukawa Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayuki Sakamoto Department of Optical Neural and Molecular Physiology, Graduate School of Biostudies Yuki Sudo Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Faculty of Medicine, Dentistry and Pharmaceutical Sciences Microbial rhodopsin is a family of photoreceptive membrane proteins that commonly consist of a seven-transmembrane domain and a derivative of vitamin-A, retinal, as a chromophore. In 2011, archaeorhodopsin-3 (AR3) was shown to exhibit voltage-dependent fluorescence changes in mammalian cells. Since then, AR3 and its variants have been used as genetically encoded voltage indicators, in which mostly intense laser stimulation (1-1000 W/cm(2)) is used for the detection of dim fluorescence of rhodopsin, leading to high spatiotemporal resolution. However, intense laser stimulation potentially causes serious cell damage, particularly during long-term imaging over minutes. In this study, we present the successful detection of voltage-sensitive fluorescence of AR3 and its high fluorescence mutant Archon1 in a variety of mammalian cell lines using low-intensity light emitting diode stimulation (0.15 W/cm2) with long exposure time (500 ms). The detection system enables real-time imaging of drug-induced slow changes in voltage within the cells for minutes harmlessly and without fluorescence bleaching. Therefore, we demonstrate a method to quantitatively understand the dynamics of slow changes in membrane voltage on long time scales. No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 2470-1343 7 50 2022 Oligoarginine-Conjugated Peptide Foldamers Inhibiting Vitamin D Receptor-Mediated Transcription 46573 46582 EN Mami Takyo National Institute of Health Sciences Yumi Sato National Institute of Health Sciences Naoya Hirata National Institute of Health Sciences Keisuke Tsuchiya National Institute of Health Sciences Hiroaki Ishida Laboratory of Drug Design and Medicinal Chemistry, Showa Pharmaceutical University Takashi Kurohara National Institute of Health Sciences Yuta Yanase National Institute of Health Sciences Takahito Ito National Institute of Health Sciences Yasunari Kanda National Institute of Health Sciences Keiko Yamamoto Laboratory of Drug Design and Medicinal Chemistry, Showa Pharmaceutical University Takashi Misawa National Institute of Health Sciences Yosuke Demizu National Institute of Health Sciences The vitamin D receptor (VDR) is a nuclear receptor, which is involved in several physiological processes, including differentiation and bone homeostasis. The VDR is a promising target for the development of drugs against cancer and bone-related diseases. To date, several VDR antagonists, which bind to the ligand binding domain of the VDR and compete with the endogenous agonist 1 alpha,25(OH)D3, have been reported. However, these ligands contain a secosteroidal skeleton, which is chemically unstable and complicated to synthesize. A few VDR antagonists with a nonsecosteroidal skeleton have been reported. Alternative inhibitors against VDR transactivation that act via different mechanisms are desirable. Here, we developed peptide-based VDR inhibitors capable of disrupting the VDR-coactivator interaction. It was reported that helical SRC2-3 peptides strongly bound to the VDR and competed with the coactivator in vitro. Therefore, we designed and synthesized a series of SRC2-3 derivatives by the introduction of nonproteinogenic amino acids, such as beta-amino acids, and by side-chain stapling to stabilize helical structures and provide resistance against digestive enzymes. In addition, conjugation with a cell-penetrating peptide increased the cell membrane permeability and was a promising strategy for intracellular VDR inhibition. The nona-arginine-conjugated peptides 24 with side-chain stapling and 25 with cyclic beta-amino acids showed strong intracellular VDR inhibitory activity, resulting in suppression of the target gene expression and inhibition of the cell differentiation of HL-60 cells. Herein, the peptide design, structure-activity relationship (SAR) study, and biological evaluation of the peptides are described. No potential conflict of interest relevant to this article was reported.

Royal Society of Chemistry (RSC) Acta Medica Okayama 1477-0520 21 3 2022 Chemical synthesis and antifouling activity of monoterpene–furan hybrid molecules 632 638 EN Hiroyoshi Takamura Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Yuya Kinoshita Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Takefumi Yorisue Institute of Natural and Environmental Sciences, University of Hyogo Isao Kadota Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Geraniol, a monoterpene, and furan are structural motifs that exhibit antifouling activity. In this study, monoterpene-furan hybrid molecules with potentially enhanced antifouling activity were designed and synthesized. The nine synthetic hybrids showed antifouling activity against the cypris larvae of the barnacle Balanus (Amphibalanus) amphitrite with EC50 values of 1.65-4.70 mu g mL(-1). This activity is higher than that of geraniol and the reference furan compound. This hybridization approach to increase antifouling activity is useful and can also be extended to other active structural units. No potential conflict of interest relevant to this article was reported.

Nature Portfolio Acta Medica Okayama 2399-3669 5 1 2022 High-resolution spectroscopy of buffer-gas-cooled phthalocyanine 161 EN Yuki Miyamoto Research Institute for Interdisciplinary Science, Okayama University Reo Tobaru Research Institute for Interdisciplinary Science, Okayama University Yuiki Takahashi Division of Physics, Mathematics, and Astronomy, California Institute of Technology Ayami Hiramoto Research Institute for Interdisciplinary Science, Okayama University Kana Iwakuni Institute for Laser Science, University of Electro-Communications Susumu Kuma Atomic, Molecular and Optical Physics Laboratory, RIKEN Katsunari Enomoto 5Department of Physics, University of Toyama Masaaki Baba Molecular Photoscience Research Center, Kobe University For over five decades, studies in the field of chemical physics and physical chemistry have primarily aimed to understand the quantum properties of molecules. However, high-resolution rovibronic spectroscopy has been limited to relatively small and simple systems because translationally and rotationally cold samples have not been prepared in sufficiently large quantities for large and complex systems. In this study, we present high-resolution rovibronic spectroscopy results for large gas-phase molecules, namely, free-base phthalocya-nine (FBPc). The findings suggest that buffer-gas cooling may be effective for large molecules introduced via laser ablation. High-resolution electronic spectroscopy, combined with other experimental and theoretical studies, will be useful in understanding the quantum properties of molecules. These findings also serve as a guide for quantum chemical calculations of large molecules. No potential conflict of interest relevant to this article was reported.

Nature Portfolio Acta Medica Okayama 2045-2322 12 1 2022 Defect-free and crystallinity-preserving ductile deformation in semiconducting Ag2S 19458 EN Masaaki Misawa Faculty of Natural Science and Technology, Okayama University Hinata Hokyo Department of Physics, Kumamoto University Shogo Fukushima Department of Physics, Kumamoto University Kohei Shimamura Department of Physics, Kumamoto University Akihide Koura Department of Physics, Kumamoto University Fuyuki Shimojo Department of Physics, Kumamoto University Rajiv K. Kalia Collaboratory for Advanced Computing and Simulations, Department of Physics and Astronomy, Department of Computer Science, Department of Chemical Engineering and Materials Science, and Department of Biological Science, University of Southern California Aiichiro Nakano Collaboratory for Advanced Computing and Simulations, Department of Physics and Astronomy, Department of Computer Science, Department of Chemical Engineering and Materials Science, and Department of Biological Science, University of Southern California Priya Vashishta Collaboratory for Advanced Computing and Simulations, Department of Physics and Astronomy, Department of Computer Science, Department of Chemical Engineering and Materials Science, and Department of Biological Science, University of Southern California Typical ductile materials are metals, which deform by the motion of defects like dislocations in association with non-directional metallic bonds. Unfortunately, this textbook mechanism does not operate in most inorganic semiconductors at ambient temperature, thus severely limiting the development of much-needed flexible electronic devices. We found a shear-deformation mechanism in a recently discovered ductile semiconductor, monoclinic-silver sulfide (Ag2S), which is defect-free, omni-directional, and preserving perfect crystallinity. Our first-principles molecular dynamics simulations elucidate the ductile deformation mechanism in monoclinic-Ag2S under six types of shear systems. Planer mass movement of sulfur atoms plays an important role for the remarkable structural recovery of sulfur-sublattice. This in turn arises from a distinctively high symmetry of the anion-sublattice in Ag2S, which is not seen in other brittle silver chalcogenides. Such mechanistic and lattice-symmetric understanding provides a guideline for designing even higher-performance ductile inorganic semiconductors. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1523-7060 24 42 2022 Total Synthesis of Scabrolide F 7845 7849 EN Hiroyoshi Takamura Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Yuki Sugitani Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Ryohei Morishita 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 The first total synthesis of scabrolide F, a norcembranolide isolated from the soft coral Sinularia scabra, is described. Hydroxycarboxylic acid, which is the key synthetic intermediate, was synthesized in a convergent manner by fragment coupling. The obtained hydroxycarboxylic acid was subjected to macrolactonization and subsequent transannular ring-closing metathesis (RCM) to furnish scabrolide F. The synthetic protocol can be extended to the total synthesis of other norcembranolides. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1996-1944 15 21 2022 Does Multifunctional Acrylate's Addition to Methacrylate Improve Its Flexural Properties and Bond Ability to CAD/CAM PMMA Block? 7564 EN Yukinori Maruo Department of Prosthodontics, Okayama University Kumiko Yoshihara Health Research Institute, National Institute of Advanced Industrial Science and Technology Masao Irie Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Noriyuki Nagaoka Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School Takuya Matsumoto Department of Biomaterials, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shogo Minagi Department of Prosthodontics, Okayama University This study investigated the effects of a multifunctional acrylate copolymer-Trimethylolpropane Triacrylate (TMPTA) and Di-pentaerythritol Polyacrylate (A-DPH)-on the mechanical properties of chemically polymerized acrylic resin and its bond strength to a CAD/CAM polymethyl methacrylate (PMMA) disk. The methyl methacrylate (MMA) samples were doped with one of the following comonomers: TMPTA, A-DPH, or Trimethylolpropane Trimethacrylate (TMPTMA). The doping ratio ranged from 10 wt% to 50 wt% in 10 wt% increments. The flexural strength (FS) and modulus (FM) of PMMA with and without comonomer doping, as well as the shear bond strength (SBS) between the comonomer-doped PMMA and CAD/CAM PMMA disk, were evaluated. The highest FS (93.2 +/- 4.2 MPa) was obtained when doped with 20 wt% of TMPTA. For TMPTMA, the FS decreased with the increase in the doping ratio. For SBS, TMPTA showed almost constant values (ranging from 7.0 to 8.2 MPa) regardless of the doping amount, and A-DPH peaked at 10 wt% doping (8.7 +/- 2.2 MPa). TMPTMA showed two peaks at 10 wt% (7.2 +/- 2.6 MPa) and 40 wt% (6.5 +/- 2.3 MPa). Regarding the failure mode, TMPTMA showed mostly adhesive failure between the CAD/CAM PMMA disk and acrylic resin while TMPTA and A-DPH showed an increased rate of cohesive or mixed failures. Acrylate's addition as a comonomer to PMMA provided improved mechanical properties and bond strength to the CAD/CAM PMMA disk. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 1520-6106 126 38 2022 Roles of the Flexible Primary Coordination Sphere of the Mn4CaOx Cluster: What Are the Immediate Decay Products of the S-3 State? 7212 7228 EN Hiroshi Isobe Research Institute for Interdisciplinary Science, Okayama University Mitsuo Shoji Center for Computational Science, University of Tsukuba, Takayoshi Suzuki Research Institute for Interdisciplinary Science, Okayama University Jian-Ren Shen Research Institute for Interdisciplinary Science, Okayama University Kizashi Yamaguchi Institute for NanoScience Design, Osaka University The primary coordination sphere of the multinuclear cofactor (Mn4CaOx) in the oxygen-evolving complex (OEC) of photosystem II is absolutely conserved to maintain its structure and function. Recent time-resolved serial femtosecond crystallography identified large reorganization of the primary coordination sphere in the S-2 to S-3 transition, which elicits a cascade of events involving Mn oxidation and water molecule binding to a putative catalytic Mn site. We examined how the crystallographic fields, created by transient conformational states of the OEC at various time points, affect the thermodynamics of various isomers of the Mn cluster using DFT calculations, with an aim of comprehending the functional roles of the flexible primary coordination sphere in the S-2 to S-3 transition and in the recovery of the S-2 state. The results show that the relative movements of surrounding residues change the size and shape of the cavity of the cluster and thereby affect the thermodynamics of various catalytic intermediates as well as the ability to capture a new water molecule at a coordinatively unsaturated site. The implication of these findings is that the protein dynamics may serve to gate the catalytic reaction efficiently by controlling the sequence of Mn oxidation/reduction and water binding/release. This interpretation is consistent with EPR experiments; g similar to 5 and g similar to 3 signals obtained after near-infrared (NIR) excitation of the S-3 state at 4 K and a g similar to 5 only signal produced after prolonged incubation of the S-3 state at 77 K can be best explained as originating from water-bound S-2 clusters (S-total = 7/2) under a S-3 ligand field, i.e., the immediate one-electron reduction products of the oxyl-oxo (S-total = 6) and hydroxo-oxo (S-total = 3) species in the S-3 state. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2022 The aetiology of mesothelioma: morphological and chemical analyses of asbestos ferruginous bodies EN AVRAMESCU MAYA LILIANA Graduate School of Natural Science and Technology, Okayama university No potential conflict of interest relevant to this article was reported.

The Chemical Society of Japan Acta Medica Okayama 0366-7022 51 9 2022 Polyiodide Production Triggered by Acidic Phase of Aqueous Solution Confined in Carbon Nanospace 971 974 EN Takahiro Ohkubo Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Yuri Hirano Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Hiroki Nakayasu Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Yasushige Kuroda Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Polyiodide species were synthesized by the acceleration of an acidic environment in the nanospace of single-walled carbon nanotubes (SWCNT) with light irradiation. Raman and EXAFS results strongly support the production of polyiodide species after the adsorption of CsI on SWCNT from aqueous solution. Interestingly, the reaction was initiated by the nano-confined acidic phase formed in a basic environment. The acidic phase plays an essential role as an oxidant for the production of the diiodine that is a source of polyiodide. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2076-3417 12 19 2022 Machine Learning and Inverse Optimization for Estimation of Weighting Factors in Multi-Objective Production Scheduling Problems 9472 EN Hidetoshi Togo Graduate School of Natural Science and Technology, Okayama University Kohei Asanuma Graduate School of Engineering Science, Osaka University Tatsushi Nishi Graduate School of Natural Science and Technology, Okayama University Ziang Liu Graduate School of Natural Science and Technology, Okayama University In recent years, scheduling optimization has been utilized in production systems. To construct a suitable mathematical model of a production scheduling problem, modeling techniques that can automatically select an appropriate objective function from historical data are necessary. This paper presents two methods to estimate weighting factors of the objective function in the scheduling problem from historical data, given the information of operation time and setup costs. We propose a machine learning-based method, and an inverse optimization-based method using the input/output data of the scheduling problems when the weighting factors of the objective function are unknown. These two methods are applied to a multi-objective parallel machine scheduling problem and a real-world chemical batch plant scheduling problem. The results of the estimation accuracy evaluation show that the proposed methods for estimating the weighting factors of the objective function are effective. No potential conflict of interest relevant to this article was reported.

Frontiers Media S.A. Acta Medica Okayama 1663-9812 13 2022 Anxiolytic-like effects of hochuekkito in lipopolysaccharide-treated mice involve interleukin-6 inhibition 890048 EN Soichiro Ushio Department of Pharmacy, Okayama University Hospital Yudai Wada Department of Clinical Pharmacy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Mizuki Nakamura Department of Clinical Pharmacy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Daiki Matsumoto Department of Clinical Pharmacy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kota Hoshika Department of Clinical Pharmacy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shoya Shiromizu Department of Pharmacy, Okayama University Hospital Naohiro Iwata Department of Pharmacy, Okayama University Hospital Satoru Esumi Department of Pharmacy, Okayama University Hospital Makoto Kajizono Department of Pharmacy, Okayama University Hospital Yoshihisa Kitamura Department of Pharmacy, Okayama University Hospital Toshiaki Sendo Department of Pharmacy, Okayama University Hospital Hochuekkito (HET) is a Kampo medicine used to treat postoperative and post-illness general malaise and decreased motivation. HET is known to regulate immunity and modulate inflammation. However, the precise mechanism and effects of HET on inflammation-induced central nervous system disorders remain unclear. This study aimed to assess the effect of HET on inflammation-induced anxiety-like behavior and the mechanism underlying anxiety-like behavior induced by lipopolysaccharide (LPS). Institute of Cancer Research mice were treated with LPS (300 mu g/kg, intraperitoneally), a bacterial endotoxin, to induce systemic inflammation. The mice were administered HET (1.0 g/kg, orally) once a day for 2 weeks before LPS treatment. The light-dark box test and the hole-board test were performed 24 h after the LPS injection to evaluate the effects of HET on anxiety-like behaviors. Serum samples were obtained at 2, 5, and 24 h after LPS injection, and interleukin-6 (IL-6) levels in serum were measured. Human and mouse macrophage cells (THP-1 and RAW264.7 cells, respectively) were used to investigate the effect of HET on LPS-induced IL-6 secretion. The repeated administration of HET prevented anxiety-like behavior and decreased serum IL-6 levels in LPS-treated mice. HET significantly suppressed LPS-induced IL-6 secretion in RAW264.7 and THP-1 cells. Similarly, glycyrrhizin, one of the chemical constituents of HET, suppressed LPS-induced anxiety-like behaviors. Our study revealed that HET ameliorated LPS-induced anxiety-like behavior and inhibited IL-6 release in vivo and in vitro. Therefore, we postulate that HET may be useful against inflammation-induced anxiety-like behavior. No potential conflict of interest relevant to this article was reported.

Nature Portfolio Acta Medica Okayama 2045-2322 12 1 2022 Cancer stem cells induced by chronic stimulation with prostaglandin E2 exhibited constitutively activated PI3K axis 15628 EN Hideki Minematsu Laboratory of Nao‑Biotechnology, Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Said M. Afify Division of Biochemistry, Chemistry Department, Faculty of Science, Menoufa University Yuki Sugihara R&D Center, Katayama Chemicals Ind., Co. Ltd, Ina, Minoh Ghmkin Hassan Department of Biotechnology and Drug Discovery, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Maram H. Zahra Department of Biotechnology and Drug Discovery, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Akimasa Seno Department of Biotechnology and Drug Discovery, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Masaki Adachi R&D Center, Katayama Chemicals Ind., Co. Ltd, Ina, Minoh Masaharu Seno Department of Biotechnology and Drug Discovery, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Previously, our group has demonstrated establishment of Cancer Stem Cell (CSC) models from stem cells in the presence of conditioned medium of cancer cell lines. In this study, we tried to identify the factors responsible for the induction of CSCs. Since we found the lipid composition could be traced to arachidonic acid cascade in the CSC model, we assessed prostaglandin E2 (PGE2) as a candidate for the ability to induce CSCs from induced pluripotent stem cells (iPSCs). Mouse iPSCs acquired the characteristics of CSCs in the presence of 10 ng/mL of PGE2 after 4 weeks. Since constitutive Akt activation and pik3cg overexpression were found in the resultant CSCs, of which growth was found independent of PGE2, chronic stimulation of the receptors EP-2/4 by PGE2 was supposed to induce CSCs from iPSCs through epigenetic effect. The bioinformatics analysis of the next generation sequence data of the obtained CSCs proposed not only receptor tyrosine kinase activation by growth factors but also extracellular matrix and focal adhesion enhanced PI3K pathway. Collectively, chronic stimulation of stem cells with PGE2 was implied responsible for cancer initiation enhancing PI3K/Akt axis. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 76 4 2022 5-Nitro-2-(3-phenylpropylamino) Benzoic Acid Inhibits the Proliferation and Migration of Lens Epithelial Cells by Blocking CaMKII Signaling 415 421 EN Haijun Kang Department of Ophthalmology, Suining Central Hospital Dongmei Huang Department of Cardiovascular, Suining Central Hospital Gangjin Kang Department of Ophthalmology, The Affiliated Hospital of Southwest Medical University Xu Yang Department of Ophthalmology, Suining Central Hospital Heng Li Department of Ophthalmology, Suining Central Hospital Siyuan Liu Department of Ophthalmology, Suining Central Hospital Wenjun Gou Department of Ophthalmology, Suining Central Hospital Linglin Liu Department of Ophthalmology, Suining Central Hospital Yuyan Qiu Department of Ophthalmology, Suining Central Hospital Original Article 10.18926/AMO/63896 Posterior capsule opacification (PCO) is a post-surgery complication of cataract surgery, and lens epithelial cells (LECs) are involved in its development. A suppressive effect on LECs is exerted by the non specific chloride channel inhibitor 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) exerts. Herein, the growth and migration inhibitory effects of NPPB on LECs were assessed, and the mechanism underlying the effects were investigated by focusing on Ca2+/CaMKII signaling. LECs were treated with different concentrations of NPPB, and the changes in cell viability, cell-cycle distribution, anchorage-dependent growth, migration, Ca2+ level, and CaMKII expression were evaluated. NPPB inhibited LECs’ proliferation and induced G1 cell-cycle arrest in the cells. Regarding LECs’ mobility, NPPB suppressed the cells’ anchorage-dependent growth ability and inhibited their migration. Changes in cell phenotypes were associated with an increased intracellular Ca2+ level and down-regulation of CaMKII. Together these results confirmed the inhibitory effect of NPPB on the proliferation and migration of LECs, and the effect was shown to be associated with the induced level of Ca2+ and the inhibition of CaMKII signaling transduction. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 76 4 2022 Therapeutic Approaches Targeting miRNA in Systemic Lupus Erythematosus 359 371 EN Sumie Hiramatsu-Asano Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Jun Wada Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Review 10.18926/AMO/63887 Systemic lupus erythematosus (SLE) is a potentially fatal systemic autoimmune disease, and its etiology involves both genetic and environmental factors such as sex hormone imbalance, genetic predisposition, epigenetic regulation, and immunological factors. Dysregulation of microRNA (miRNA) is suggested to be one of the epigenetic factors in SLE. miRNA is a 22-nucleotide single-stranded noncoding RNA that contributes to post-transcriptional modulation of gene expression. miRNA targeting therapy has been suggested to be useful for the treatment of cancers and other diseases. Gene knockout and miRNA targeting therapy have been demonstrated to improve SLE disease activity in mice. However, these approaches have not yet reached the level of clinical application. miRNA targeting therapy is limited by the fact that each miRNA has multiple targets. In addition, the expression of certain miRNAs may differ among cell tissues within a single SLE patient. This limitation can be overcome by targeted delivery and chemical modifications. In the future, further research into miRNA chemical modifications and delivery systems will help us develop novel therapeutic agents for SLE. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0163-3864 85 8 2022 First Total Synthesis of Reassigned Echinosulfonic Acid D 2122 2125 EN Takumi Abe Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ren Nakajima Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiki Yamashiro Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Daisuke Sawada Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Echinosulfonic acid D, a sponge metabolite whose structure was recently reassigned, was synthesized for the first time. The key step is the double indolization of dimethylbarbituric acid using the umpolung indole reagent, followed by a hydrolysis/decarboxylation/esterification sequence. No potential conflict of interest relevant to this article was reported.

ROYAL SOC CHEMISTRY Acta Medica Okayama 2041-6520 13 2022 Annulative coupling of vinylboronic esters: aryne-triggered 1,2-metallate rearrangement 9580 9585 EN Haruki Mizoguchi Graduate School of Natural Science and Technology, Okayama University Hidetoshi Kamada Graduate School of Natural Science and Technology, Okayama University Kazuki Morimoto Graduate School of Natural Science and Technology, Okayama University Ryuji Yoshida Graduate School of Natural Science and Technology, Okayama University Akira Sakakura Graduate School of Natural Science and Technology, Okayama University A stereoselective annulative coupling of a vinylboronic ester ate-complex with arynes producing cyclic borinic esters has been developed. An annulation reaction that proceeded through the formation of two C-C bonds and a C-B bond was realized by exploiting a 1,2-metallate rearrangement of boronate triggered by the addition of a vinyl group to the strained triple bond of an aryne. The generated aryl anion would then cyclize to a boron atom to complete the annulation cascade. The annulated borinic ester could be converted to boronic acids and their derivatives by oxidation, halogenation, and cross-coupling. Particularly, halogenation and Suzuki-Miyaura coupling proceeded in a site-selective fashion and produced highly substituted alkylboronic acid derivatives. No potential conflict of interest relevant to this article was reported.

AIP Publishing Acta Medica Okayama 0021-9606 156 22 2022 Osmotic second virial coefficients for hydrophobic interactions as a function of solute size 221104 EN Hidefumi Naito Department of Chemistry, Faculty of Science, Okayama University Ryuichi Okamoto 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 To gain quantitative insight into how the overall strength of the hydrophobic interaction varies with the molecular size, we calculate osmotic second virial coefficients B for hydrophobic spherical molecules of different diameters σ in water based on molecular simulation with corrections to the finite-size and finite-concentration effects. It is shown that B (&lt;0) changes by two orders of magnitude greater as σ increases twofold and its solute-size dependence is best fit by a power law B ∝ σ<jats:sup> α</jats:sup> with the exponent α ≃ 6, which contrasts with the cubic power law that the second virial coefficients of gases obey. It is also found that values of B for the solutes in a nonpolar solvent are positive but they obey the same power law as in water. A thermodynamic identity for B derived earlier [K. Koga, V. Holten, and B. Widom, J. Phys. Chem. B 119, 13391 (2015)] indicates that if B is asymptotically proportional to a power of σ, the exponent α must be equal to or greater than 6. No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 2470-1343 2022 Characteristics of Vertical Ga2O3 Schottky Junctions with the Interfacial Hexagonal Boron Nitride Film 26021 26028 EN Venkata Krishna Rao Rama Graduate School of Natural Science and Technology, Okayama University Ajinkya K. Ranade Department of Physical Science and Engineering, Nagoya Institute of Technology Pradeep Desai Department of Physical Science and Engineering, Nagoya Institute of Technology Bhagyashri Todankar Department of Physical Science and Engineering, Nagoya Institute of Technology Golap Kalita Department of Physical Science and Engineering, Nagoya Institute of Technology Hiroo Suzuki Graduate School of Natural Science and Technology Masaki Tanemura Department of Physical Science and Engineering, Nagoya Institute of Technology Yasuhiko Hayashi We present the device properties of a nickel (Ni)- gallium oxide (Ga2O3) Schottky junction with an interfacial hexagonal boron nitride (hBN) layer. A vertical Schottky junction with the configuration Ni/hBN/Ga2O3/In was created using a chemical vapor-deposited hBN film on a Ga(2)O(3 )substrate. The current-voltage characteristics of the Schottky junction were investigated with and without the hBN interfacial layer. We observed that the turn-on voltage for the forward current of the Schottky junction was significantly enhanced with the hBN interfacial film. Furthermore, the Schottky junction was analyzed under the illumination of deep ultraviolet light (254 nm), obtaining a photoresponsivity of 95.11 mA/W under an applied bias voltage (-7.2 V). The hBN interfacial layer for the Ga2O3-based Schottky junction can serve as a barrier layer to control the turn-on voltage and optimize the device properties for deep-UV photosensor applications. Furthermore, the demonstrated vertical heterojunction with an hBN layer has the potential to be significant for temperature management at the junction interface to develop reliable Ga2O3-based Schottky junction devices. No potential conflict of interest relevant to this article was reported.

American Chemical Society (ACS) Acta Medica Okayama 0887-0624 36 18 2022 Structure Selectivity of Mixed Gas Hydrates and Group 14 Clathrates 10667 10674 EN Masakazu Matsumoto Research Institute for Interdisciplinary Science, Okayama University Hideki Tanaka Toyota Physical and Chemical Research Institute The structure selectivity of mixed gas hydrates and group 14 clathrates is examined on the basis of statistical mechanical theories and the empirical rule on the topological constraint of the Frank-Kasper phases. The most stable structure is revealed by the generalized phase diagram, where the chemical potential differences in the three canonical forms of clathrates are independent variables. The most stable structure incorporating individual guest species is evaluated by the locus of the chemical potential differences on this generalized phase diagram. We show that the method developed here is simple but powerful to estimate roughly phase behaviors of clathrate compounds in a wide range of thermodynamic conditions, which is demonstrated by two applications: the generalized phase diagram of group 14 element clathrates and the phase behavior of mixed gas hydrates. The present theory leads to proposals of phase change agents, of which the addition sensitively influences the structure selectivity, encompassing even minor structures. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1422-0067 23 12 2022 Control of STING Agonistic/Antagonistic Activity Using Amine-Skeleton-Based c-di-GMP Analogues 6847 EN Yuta Yanase National Institute of Health Sciences Genichiro Tsuji National Institute of Health Sciences Miki Nakamura Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Division of Pharmaceutical Science of Okayama University Norihito Shibata National Institute of Health Sciences Yosuke Demizu Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Division of Pharmaceutical Science of Okayama University Stimulator of Interferon Genes (STING) is a type of endoplasmic reticulum (ER)-membrane receptor. STING is activated by a ligand binding, which leads to an enhancement of the immune-system response. Therefore, a STING ligand can be used to regulate the immune system in therapeutic strategies. However, the natural (or native) STING ligand, cyclic-di-nucleotide (CDN), is unsuitable for pharmaceutical use because of its susceptibility to degradation by enzymes and its low cell-membrane permeability. In this study, we designed and synthesized CDN derivatives by replacing the sugar-phosphodiester moiety, which is responsible for various problems of natural CDNs, with an amine skeleton. As a result, we identified novel STING ligands that activate or inhibit STING. The cyclic ligand 7, with a cyclic amine structure containing two guanines, was found to have agonistic activity, whereas the linear ligand 12 showed antagonistic activity. In addition, these synthetic ligands were more chemically stable than the natural ligands. No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 1932-7447 126 22 2022 Role of Oxygen Vacancy in the Photocarrier Dynamics of WO3 Photocatalysts: The Case of Recombination Centers 9257 9263 EN Kosaku Kato Graduate School of Natural Science and Technology, Okayama University Yohei Uemura Institute for Molecular Science Kiyotaka Asakura Institute for Catalysis, Hokkaido University Akira Yamakata Graduate School of Natural Science and Technology, Okayama University Defects in powder photocatalysts determine the photocatalytic activity. The addition of defects sometimes enhances the activity, but sometimes decreases it. However, the factors determining the difference between these cases have not been fully elucidated yet. Herein, we investigated the effects of oxygen vacancies on photocarrier dynamics in WO3 powder using broadband transient absorption spectroscopy. It was found that the decay of deeply trapped electrons was accelerated when the number of oxygen vacancies was increased by H-2 reduction. This result suggests that oxygen vacancies in WO3 mainly act as recombination centers. This is in contrast to many other photocatalysts such as TiO2 and SrTiO3, where the carrier lifetime increases with increasing oxygen vacancy concentration. These differences can be attributed to the difference in the distance between oxygen vacancies. When defects are dispersed, trapped electrons need to travel over long distances by repeatedly hopping and tunneling between defects to combine with holes, resulting in decelerated recombination. In contrast, when the defects are connected or located close together, the trapped electrons can readily migrate among defects, leading to enhanced recombination. Control of the distance between defects is thus important for enhancing photocatalytic activity. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 0947-6539 28 37 2022 Design and Synthesis of Glycosylated Cholera Toxin B Subunit as a Tracer of Glycoprotein Trafficking in Organelles of Living Cells e202201253 EN Yuta Maki Department of Chemistry, Graduate School of Science, Osaka University Kazuki Kawata Department of Chemistry, Graduate School of Science, Osaka University Yanbo Liu Department of Chemistry, Graduate School of Science, Osaka University Kang‐Ying Goo Department of Chemistry, Graduate School of Science, Osaka University Ryo Okamoto Department of Chemistry, Graduate School of Science, Osaka University Yasuhiro Kajihara Department of Chemistry, Graduate School of Science, Osaka University Ayano Satoh Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Glycosylation of proteins is known to be essential for changing biological activity and stability of glycoproteins on the cell surfaces and in body fluids. Delivering of homogeneous glycoproteins into the endoplasmic reticulum (ER) and the Golgi apparatus would enable us to investigate the function of asparagine-linked (N-) glycans in the organelles. In this work, we designed and synthesized an intentionally glycosylated cholera toxin B-subunit (CTB) to be transported to the organelles of mammalian cells. The heptasaccharide, the intermediate structure of various complex-type N-glycans, was introduced to the CTB. The synthesized monomeric glycosyl-CTB successfully entered mammalian cells and was transported to the Golgi and the ER, suggesting the potential use of synthetic CTB to deliver and investigate the functions of homogeneous N-glycans in specific organelles of living cells. No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 2470-1343 7 15 2022 Eco-Benign Orange-Hued Pigment Derived from Aluminum-Enriched Biogenous Iron Oxide Sheaths 12795 12802 EN Katsunori Tamura Graduate School of Natural Science and Technology, Okayama University Yuri Oshima Graduate School of Natural Science and Technology, Okayama University Yuta Fuse Graduate School of Natural Science and Technology, Okayama University Noriyuki Nagaoka Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Tatsuki Kunoh Graduate School of Natural Science and Technology, Okayama University Makoto Nakanishi Graduate School of Natural Science and Technology, Okayama University Tatsuo Fujii Graduate School of Natural Science and Technology, Okayama University Tokuro Nanba Graduate School of Environmental and Life Science, Okayama University Jun Takada Graduate School of Natural Science and Technology, Okayama University Inorganic pigments have been widely used due to their low cost of production, strong hiding power, and chemical resistance; nevertheless, they have limited hue width and chromaticity. To eliminate these disadvantages, we herein propose the use of an ingenious biotemplate technique to produce Al-enriched biogenic iron oxide (BIOX) materials. Spectrophotometric color analysis showed that high levels of Al inclusion on heat-treated BIOX samples produced heightened yellowish hues and lightness. The Al-enriched BIOX sheaths exhibited a stable tubular structure and excellent thermal stability of color tones after heating at high temperatures and repetitive heat treatments. Ultrastructural analysis and mechanical destruction experiments revealed that the highly chromatic orange-hue of these pigments are ascribed probably to an ingenious cylindrical nanocomposite architecture composed of putative Fe-included low crystalline Al oxide regions and hematite particles embedded therein. The present work therefore demonstrates that the bioengineered material can serve as an epochal orange-hued inorganic pigment with low toxicity and marked thermostability that should meet large industrial demand. No potential conflict of interest relevant to this article was reported.

American Chemical Society Acta Medica Okayama 2379-3694 7 4 2022 Dip-and-Read, Organic Solvent-Compatible, Paper-Based Analytical Devices Equipped with Chromatographic Separation for Indole Analysis in Shrimp 1194 1200 EN Sasikarn Seetasang Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University Takashi Kaneta Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University We developed an organic solvent-compatible paper-based analytical device (PAD) for the quantitative analysis of indole, which is an indicator of shrimp freshness. Although indole is insoluble in water, ethyl acetate is a suitable solvent to dissolve and extract indole from shrimp. The PADs are fabricated using a cutting method that allows the use of an organic solvent because no hydrophobic barrier is needed to form fluidic channels. Ehrlich's reagent consists of 4-(dimethylamino)benzaldehyde and p-dimethylaminobenzaldehyde and was deposited onto the reaction zone of the PAD followed by lamination to prevent evaporation of the ethyl acetate. Samples are introduced into the PAD via immersion in organic sample solutions. When the PAD is immersed into an indole solution of ethyl acetate in a closed bottle, the sample solution penetrates the channel of the PAD and successively flows into the detection zone to form a hydrophilic colored product. The PADs provide a linear relationship between the logarithm of the indole concentration and the color intensity within a range of 1.0-20 ppm with correlation coefficients of r2 > 0.99. The limits of detection and quantification are 0.36 and 0.71 ppm, respectively. Relative standard deviations for both the intraday (n = 2) and interday (n = 3) precision were less than 2.5%. In the indole analysis of shrimp, the PADs separated the interfering orange-colored astaxanthin in the extract from the colored product of indole via the paper chromatographic principle. We used the PADs to investigate the degradation of shrimp, and the results showed a rapid increase in the indole level after 7 days. High-performance liquid chromatography verified the accuracy of the PADs by showing good agreement with the obtained indole levels. No potential conflict of interest relevant to this article was reported.

American Physical Society (APS) Acta Medica Okayama 2470-0045 105 4 2022 Lattice Boltzmann model for capillary interactions between particles at a liquid-vapor interface under gravity 045316 EN Yasushi Mino Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Hazuki Tanaka Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Koichi Nakaso Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Kuniaki Gotoh Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Hiroyuki Shinto Department of Chemical Engineering, Fukuoka University A computational technique based on the lattice Boltzmann method (LBM) is developed to simulate the wettable particles adsorbed to a liquid-vapor interface under gravity. The proposed technique combines the improved smoothed-profile LBM for the treatment of moving solid particles in a fluid and the free-energy LBM for the description of a liquid-vapor system. Five benchmark two-dimensional problems are examined: (A) a stationary liquid drop in the vapor phase; a wettable particle adsorbed to a liquid-vapor interface in (B) the absence and (C) the presence of gravity; (D) two freely moving particles at a liquid-vapor interface in the presence of gravity (i.e., capillary flotation forces); and (E) two vertically constrained particles at a liquid-vapor interface (i.e., capillary immersion forces). The simulation results are in good quantitative agreement with theoretical estimations, demonstrating that the proposed technique can reproduce the capillary interactions between wettable particles at a liquid-vapor interface under gravity. No potential conflict of interest relevant to this article was reported.

American Geophysical Union (AGU) Acta Medica Okayama 2169-9313 125 10 2020 Feedback of Slab Distortion on Volcanic Arc Evolution: Geochemical Perspective From Late Cenozoic Volcanism in SW Japan e2019JB019143 EN Tai Truong Nguyen Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Hiroshi Kitagawa Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Ivan Pineda‐Velasco Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Eizo Nakamura Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University Southwest Japan is an island arc formed by subduction of the Philippine Sea (PHS) plate. The Quaternary magmatism in this region is characterized by eruptions of high-Sr andesites and dacites, considered to have been derived by melting of the PHS plate. The loci of these volcanoes spatially coincide with seismic discontinuities of the subducted PHS plate. Thus, the magmatism is interpreted as the result of slab melting at the plate tears. However, the processes that promote slab tearing remain unclear. In this study, we applied geochronological and geochemical analyses to late Cenozoic volcanic rocks in southwest Japan as tracers of slab morphology. Two different magma types, ocean-island basalt (OIB) and island-arc basalt (IAB), have occurred over 12 million years (Myr). These two magmas are attributed to different integrations of melts extracted from an originally fertile mantle; the OIBs from high temperature melt (1,300–1,400°C) were extracted at a depth of 40–80 km, whereas the IABs were extracted from a shallower, lower temperature region (30–60 km, 1,200–1,350°C). Secular change in Sr enrichment of IAB likely arose due to a transition of slab-derived fluids, incorporated into magmas as they formed, from water- to melt-dominant one. Progressive shallowing of the subducted PHS plate is responsible for secular change in the properties of slab-derived fluids as well as rollback of OIB volcanoes. Production of chemically variable magmas in the Chugoku district is the surface expression of distorting slab morphology by interaction between mantle and the subducting plate. No potential conflict of interest relevant to this article was reported.

American Geophysical Union (AGU) Acta Medica Okayama 2169-9313 127 5 2022 Bilateral Heterogeneity in an Upwelling Mantle via Double Subduction of Oceanic Lithosphere e2021JB023328 EN Nghiem Van Dao The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University Hiroshi Kitagawa The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University Eizo Nakamura The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University Katsura Kobayashi The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Thanh Xuan Ngo Department of Geology, Hanoi University of Mining and Geology Son Hai Trinh Vietnam Institute of Geoscience and Mineral resources Vietnam is a major field of Cenozoic volcanism in Southeast (SE) Asia. Two contrasting models have been proposed to explain the mantle upwelling and volcanism in this region; collision of the Indian and Eurasian continents or subduction of the Pacific or Indo-Australian oceanic lithosphere. To place constraints on the origin of the intraplate volcanism in SE Asia, new geochronological and geochemical data for Cenozoic basalts in Vietnam are presented. Based largely on Sr-Nd-Pb isotope systematics, it was found that the sources of basalts from Central and Southern Vietnam are chemically distinct forming a sharp boundary at 13.5°N. The basalts north of the boundary show isotopic features similar to Enriched Mantle type 2 (EM2) ocean island basalts. Whereas the basalts south of the boundary show isotopic features similar to Enriched Mantle type 1 (EM1) ocean island basalts. The EM1 and EM2 basalts display positive Sr anomalies and elevated Pb/Ce and Th/La ratios, respectively. Such features suggest the origins of the sources through the recycling of deeply-subducted crustal lithologies. Furthermore, subduction of dense oceanic lithosphere can induce a convecting cell in the upper mantle. Therefore, we suggest that the chemically different basalts from Central and Southern Vietnam represent the surface expression of melting in two different convecting cells, one is driven by subduction of the Pacific plate and the other by subduction of the Indo-Australian plate. No potential conflict of interest relevant to this article was reported.

The Geological Society of America Acta Medica Okayama 1553-040X 18 3 2022 Lithium in garnet as a tracer of subduction zone metamorphic reactions: The record in ultrahigh-pressure metapelites at Lago di Cignana, Italy 1020 1029 EN Gray E. Bebout Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University Tsutomu Ota Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University Takuya Kunihiro Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University William D. Carlson Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin Eizo Nakamura Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University Lithium is of great interest as a tracer of metamorphic reactions and related fluid-mineral interactions because of its potential to isotopically fractionate during inter- and intracrystalline diffusional processes. Study of its transfer through subduction zones, based on study of arc volcanic and metamorphic rocks, can yield insight regarding ocean-to-mantle chemical cycling. We investigated major- and trace-element concentrations and delta Li-7 in garnet in ultrahigh-pressure (UHP) Lago di Cignana metasedimentary rocks, relating these observations to reconstructed prograde devolatilization history. In all garnet crystals we studied, heavy rare earth elements (HREEs), Y, and Li showed strong zoning, with elevated concentrations in cores (15-50 ppm Li) and marked high-concentration anomalies (up to 117 ppm Li, 5500 ppm Y; little or no major-element shift) as growth annuli, in which some crystals showed subtle elevation in delta Li-7 greater than analytical error of similar to 3 parts per thousand (2 sigma). Rutile inclusions appeared abruptly at annuli and outward toward rims, accompanied by inclusions of a highly zoned, Ca- and rare earth element-rich phase and decreased Nb concentrations in garnet. These relationships are interpreted to reflect prograde garnet-forming reaction(s), in part involving titanite breakdown to stabilize rutile, which resulted in delivery of more abundant Y and HREEs at surfaces of growing garnet crystals to produce annuli. Co-enrichments in Li and Y + REEs are attributed to mutual incorporation via charge-coupled substitutions; thus, increased Li uptake was a passive consequence of elevated concentrations of Y + REEs. The small-scale fluctuations in delta Li-7 (overall range of similar to 9 parts per thousand) observed in some crystals may correlate with abrupt shifts in major-and trace-element concentrations, suggesting that changes in reactant phases exerted some control on the evolution of delta Li-7. For one garnet crystal, late-stage growth following partial resorption produced deviation in major- and trace-element compositions, including Li concentration, accompanied by a 10 parts per thousand-15 parts per thousand negative shift in delta Li-7, perhaps reflecting a change in the mechanism of incorporation or source of Li. These results highlight the value of measuring the major- and trace-element and isotope compositions of garnets in high-pressure and UHP metamorphic rocks in which matrix mineral assemblages are extensively overprinted by recrystallization during exhumation histories. Lithium concentrations and isotope compositions of the garnets can add valuable information regarding prograde (and retrograde) reaction history, kinetics of porphyroblast growth, intracrystalline diffusion, and fluid-rock interactions. This work, integrated with previous study of devolatilization in the Schistes Lustres/Cignana metasedimentary suite, indicates retention of a large fraction of the initially subducted sedimentary Li budget to depths approaching those beneath volcanic fronts, despite the redistribution of this Li among mineral phases during complex mineral reaction histories. No potential conflict of interest relevant to this article was reported.