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Locally homogeneous Kaehler manifolds and Transformation groups
Get PDFこのプロジェクトでは, 大きな対称性をもつリー群Gの可微分作用がX上にあるとき閉非球形リーマン多様体X/Γの幾何構造を調べた.変換群の観点から可縮空間Xへの群作用を調べることによりX/Γを調べた.X/Γはインフラ-可解多様体をファイバーとするSeifert fiberingの構造を持つことを示した.トポロジーの観点からは群Γは群拡大: 1→Δ→Γ→ Q→ 1を持つことがわかり,Seifert fiberingを通して軌道束の繰り返しによるリーマン多様体のインフラ可解タワーが得たられ,この構造定理を使って具体的な多様体(局所等質ケーラー多様体, また局所等質佐々木多様体)を特徴づけた.The following were the subjects of my research. I.Structure of Isometry groups with radical,and aspherical Riemannian manifolds with large symmetry. Classification of infra-solv tower of fiber bundles. (Isometry groups with radical,and aspherical Riemannian manifolds with large symmetry.II.Isometric classification of compact locally homogeneous aspherical Kaehler, Sasaki manifolds. We proved every compact aspherical Riemannian manifold admits a canonical series of orbibundle structures with infra-solv fibers which is called an infra-solv tower. Its length and the geometry of its base measure the degree of continuous symmetry of an aspherical Riemannian manifold. We show that the manifold has large local symmetry if it admits a tower of orbibundle fibrations with locally homogeneous fibers infra-solv tower whose base is a locally homogeneous space. We constructed examples of aspherical manifolds with large local symmetry, which do not support any locally homogeneous Riemannian metrics.科学研究費助成事業研究成果報告書 研究種目：基盤研究(C)（一般）, 研究期間：2018～2023, 課題番号：18K03284 研究分野：幾何学とトポロジー, 研究者番号：10125304. 8p
Search for antioxidant compounds with anti-necroptosis effects and investigation of novel treatments for cerebrovascular disease
Get PDF脳梗塞中心の細胞死は制御不可能とされ、治療が放棄されてきたが、近年、制御可能なネクローシス様細胞死とし て、「ネクロトーシス」の存在が発見された。ネクロトーシス抑制は、脳梗塞の治療領域を拡大する可能性が示唆さされた。本研究では、酸化ストレスが大きく関与する脳梗塞の治療薬として、抗酸化作用と抗ネクロトーシス作用の両方を兼ね備えた化合物を探索することを目的とした。申請者は、スクリーニングより候補化合物FAD041を見出した。FAD041は、酸化ストレス傷害対して強い細胞保護効果を示した。その作用メカニズムには、FAD041の抗酸化作用や抗ネクロトーシス作用が寄与する可能性が示唆された。Cell death in the center of cerebral infarction has been considered uncontrollable, and treatment has been abandoned. However, in recent years, the existence of " necroptosis" has been discovered as a controllable necrosis-like cell death. It has been suggested that inhibition of necroptosis may expand the treatment field for cerebral infarction. In this study, the aim was to search for a compound that has both antioxidant and anti-necroptosis effects as a treatment for cerebral infarction, which is closely related to oxidative stress. The applicant found a candidate compound, FAD041, through screening. FAD041 showed a strong cytoprotective effect against oxidative stress injury. It was suggested that the antioxidant and anti-necroptosis effects of FAD041 may contribute to the mechanism of action.科学研究費助成事業研究成果報告書 研究種目：若手研究, 研究期間：2020～2023, 課題番号：20K16531 研究分野：神経薬理学, 研究者番号：50711751. 9p
Thermoresponsive degradable hydrogels with renewable surfaces for protein removal
Get PDFMost biological materials used in the body undergo protein adsorption, which alters their biological functions. Previously, we introduced surface-degradable hydrogels as adsorbed protein-removing surfaces. However, only a few surface renewals were possible because of the hydrophilic nature of the hydrogels, which accelerated their degradation. In this research, we introduced thermoresponsive properties of hydrogels for limited degradation for protein removal. Hydrogels were synthesized by the radical polymerization of N-isopropylacrylamide (NIPAAm), 2-methylene-1,3-dioxepane, and poly(ethylene glycol) monomethacrylate (PEGMA). The synthesized hydrogels demonstrated thermoresponsive behavior derived from poly(NIPAAm). At 10 °C, the hydrogels swelled and exhibited bulk degradation. After 2 h, the prepared hydrogels were degraded completely. However, at 37 °C, the hydrogels shrunk and showed surface degradation. After 7 h of degradation, the swelling ratio of the hydrogels changed marginally. The proteins adsorbed on the hydrogel surfaces were removed via surface degradation. However, the fluorescence intensity of adsorbed proteins increased on the hydrogel surfaces without degradable functions. In addition, the fluorescence intensity of adsorbed proteins increased in the hydrogels without PEG graft chains, suggesting that the prepared thermoresponsive hydrogels with PEG chains could be used as potential biomaterial surface coating materials, exhibiting regenerative low-fouling ability.This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence
ゲンダイ シャカイ オ ケンコウ デ ユタカ ニ スゴソウ
Get PDF第43回（2024年度）城西大学公開講座 全4回 開催時間：午後1時45分～午後3時30分 会場：城西大学23号館209教室 後援：坂戸市・鶴ヶ島市・日高市・川越市・飯能市・東松山市・毛呂山町・越生町・鳩山町・川島町・東秩父村の各教育委員会、埼玉東上地域大学教育プラットフォーム(TJUP)、埼玉新聞社 受講料：無料 修了証書：全4回を受講された方には修了証書を後日郵
Analysis of the Effects of Brefeldin A on Deuterium-Labeled Sphinganine Metabolism Using Liquid Chromatography–Tandem Mass Spectrometry
Get PDFCeramide (Cer) is synthesized in the endoplasmic reticulum (ER) using sphinganine as the common backbone and is then transported to the Golgi apparatus to synthesize two complex sphingolipids, sphingomyelin (SM) and glucosylceramide (GlcCer). Brefeldin A (BFA) affects the structure of the Golgi apparatus, resulting in the redistribution of the Golgi proteins into the ER. Therefore, BFA has been used to examine the ER-to-Golgi trafficking of lipids, but the detailed lipid changes in cells upon BFA treatment are not fully understood. Here, we examined the metabolism of deuterium-labeled sphinganine in HEK293T cells treated with BFA using liquid chromatography–tandem mass spectrometry. The BFA-pretreated cells were incubated in the presence of deuterium-labeled sphinganine and BFA for 5 min to 8 h, and the levels of dihydroceramide, Cer, dihydrosphingomyelin, SM, GlcCer, and phosphatidylcholine (PC) were investigated. The levels of Cer species in BFA-treated cells were lower than those in untreated cells within 2 h of incubation, but following >4 h of incubation, the levels of C14–20 Cer, encompassing C14–20 acyl chains, were similar in BFA-treated and untreated cells. Furthermore, BFA treatment increased the levels of C14–20 GlcCer but had little effect on those of C22–24 GlcCer. Moreover, after incubation for >4 h, BFA treatment decreased the levels of saturated C30–32 PC but had almost little effect on those of PC containing a monounsaturated C32–34 acyl chain. Our findings showed that BFA affected the metabolism of various lipids depending on the length and saturation of the fatty acid chain.This is an open access article distributed under the terms of Creative Commons Attribution-NonCommercial 4.0 License (https://creativecommons.org/licenses/by-nc/4.0/). Published by The Pharmaceutical Society of Japa
Final Lecture by Professor Emeritus Masayuki Morita : To Eliminate International Conflicts
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Analysis of hypergeometric equations using various transformations
Get PDFmiddle convolutionなど種々の変換を用いて特殊関数としての超幾何関数を特徴づける微分方程式の解析を行った．不分岐不確定特異点をもつ常微分方程式に普遍開折の概念を導入した．解の普遍積分表示やstokes係数の変換理論を与え，rigidな場合はすべての特異点を変数とみて多変数超幾何微分方程式へ普遍拡張されることを示した．多変数超幾何微分方程式系について，新たな積分変換を導入し，今まで解析されていなかったrigidの枠からはみ出る広いクラスが扱えるようになり，解の積分表示，べき級数表示，接続公式などの結果を得た．I analyze hypergeometric equations which characterize hypergeometric functions as special functions by applying several transformations including middle convolutions. I define versal unfoldings of ordinary differential equations with unramified irregular singular points and give versal integral representations of their solutions and a transformation theorem of Stokes coefficients of them. If the equations are rigid, I prove that they are versally extended to hypergeometric systems with several variables regarding singular points as variables. Introducing new integral transformations, I analyze a wide class of hypergeometric systems with many variables which are not necessarily rigid and give integral representations of their solutions, power series expressions of them and their connection formulas etc.科学研究費助成事業研究成果報告書 研究種目：基盤研究(C)（一般）, 研究期間：2018～2023, 課題番号：18K03341 研究分野：代数解析学, 研究者番号：50011721. 17p
A Tricyclic Aromatic Polyketide Isolated from the Marine-derived Fungus Curvularia aeria
Get PDFA novel tricyclic polyketide, curvulanone (1), was isolated from the marine-derived fungus Curvularia aeria. The structure of 1 was determined by NMR and single-crystal X-ray crystallography. 1 had a cyclopentabenzopyranone with 3-acetic acid structure that is rarely found in natural compounds. Monoamine oxidase and sirtuin 1 inhibitory test was exhibited and 1 showed their inhibitory activity