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.

Okayama University Medical School Acta Medica Okayama 0386-300X 74 4 2020 Cytotoxic Effects of Alcohol Extracts from a Plastic Wrap (Polyvinylidene Chloride) on Human Cultured Liver Cells and Mouse Primary Cultured Liver Cells 327 334 EN Ken-ichi Yamamoto Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroko Kagawa Okayama University Hospital Sakae Arimoto Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Xian Wen Tan Department of Cell Chemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kento Yasui Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiyuki Oshiki Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University Masakiyo Sakaguchi Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Original Article 10.18926/AMO/60371 An increasing accumulation of microplastics and further degraded nanoplastics in our environment is suspected to have harmful effects on humans and animals. To clarify this problem, we tested the cytotoxicity of two types of plastic wrap on human cultured liver cells and mouse primary cultured liver cells. Alcohol extracts from plastic wrap, i.e., polyvinylidene chloride (PVDC), showed cytotoxic effects on the cells. Alcohol extracts of polyethylene (PE) wrap were not toxic. The commercially available PVDC wrap consists of vinylidene chloride, epoxidized soybean oil, epoxidized linseed oil as a stiffener and stabilizer; we sought to identify which component(s) are toxic. The epoxidized soybean oil and epoxidized linseed oil exerted strong cytotoxicity, but the plastic raw material itself, vinylidene chloride, did not. Our findings indicate that plastic wraps should be used with caution in order to prevent health risks. No potential conflict of interest relevant to this article was reported.

化学工業日報社 Acta Medica Okayama 0453-0683 58 2 2011 問われる産と学の決断と勇気 50 55 EN Toshiyuki Oshiki No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama Toward Industrial Applications of Homogeneous Catalysts EN Toshiyuki Oshiki No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 高濃度ギ酸から水素を製造する化学触媒法 EN Toshiyuki Oshiki No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 有機エレクトロニクス材料の中規模製造工程の開発 EN No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 地域の産学連携による省エネ型次世代触媒技術の開発 EN No potential conflict of interest relevant to this article was reported.

Elsevier Science BV. Acta Medica Okayama 0920-5861 164 1 2011 2-Diphenylphosphanyl-4-pyridyl(dimethyl) amine as an effective ligand for the ruthenium(II) complex catalyzed homogeneous hydration of nitriles under neutral conditions 552 555 EN Makoto Muranaka Isao Hyodo Wataru Okumura Toshiyuki Oshiki New homogeneous catalyst comprised of [Ru(methallyl)(2)(cod)] (cod = 1,5-cyclooctadiene) (1) and 2-diphenylphosphanyl-4-pyridyl(dimethyl) amine (2) is shown to efficiently catalyze the hydration of various nitriles under neutral conditions. The hydration proceeds in the presence of 0.5 mol% of the ruthenium catalyst at 80 degrees C in 1,2-dimethoxyethane solution and the corresponding amide is obtained within few hours without the formation of by products. Comparison of some phosphine ligands for the hydration reveals that the dimethylamino moiety of 2 improves the catalytic performance dramatically. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2007 水-有機多相系を制御する新規錯体触媒プロセスによるシンプル水和 反応の開発 EN Toshiyuki Oshiki 極性官能基をもつニトリルやエステルを錯体触媒により水和（加水分解）し、工業的に重要なアミドや脂肪酸を得るための究極のシンプルな新規製造プロセスの開発が目的です。その実現のためには、水と油（有機化合物）の多相系を「科学的」及び「工学的」に制御することが必要です。本研究では、新たに開発する多相系制御技術を協奏的に活用し、化学産業で強く求められている環境調和の省エネルギー型水和プロセスの完成を目指します。 No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2007 タンタル上のアルキン配位子交換反応の機構研究 EN Toshiyuki Oshiki 研究内容 シリルアルキン錯体の合成とその反応性。 アルキン交換反応の速度式と活性化パラメータの算出。 アルキン交換反応の新規錯体合成への応用。 No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2007 錯体触媒による革新的化学品製造技術の開発 EN Toshiyuki Oshiki Akinori Ishiduka 水和反応は原理的に副生成物が出ないため、本質的に環境への負荷が少ない反応です。この反応に適用できる高活性触媒を開発し、しかも溶媒なしでアミド製造が実現できたことは大きなイノベーションです。さらに、これを出発点として、他の化学品を省エネルギー型水和反応により製造する技術開発を民間企業との連携により現在進めています。岡山大学では、このような自然と人間の共生を目指した研究を通じて、我が国の産業技術開発を担う人材育成に取り組んでいます。 No potential conflict of interest relevant to this article was reported.