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101.
Masaaki Tanaka Norihiro Sadato Tomohisa Okada Kei Mizuno Tetsuya Sasabe Hiroki C Tanabe Daisuke N Saito Hirotaka Onoe Hirohiko Kuratsune Yasuyoshi Watanabe 《BMC neurology》2006,6(1):9
Background
Although the neural mechanism of chronic fatigue syndrome has been investigated by a number of researchers, it remains poorly understood. 相似文献102.
Analysis of hepatic oxidative stress status by electron spin resonance spectroscopy and imaging 总被引:6,自引:0,他引:6
Togashi H Shinzawa H Matsuo T Takeda Y Takahashi T Aoyama M Oikawa K Kamada H 《Free radical biology & medicine》2000,28(6):846-853
Real-time detection of free radicals generated within the body may contribute to clarify the pathophysiological role of free radicals in disease processes. Of the techniques available for studying the generation of free radicals in biological systems, electron spin resonance (ESR) has emerged as a powerful tool for detection and identification. This article begins with a review of spin trapping detection of oxygen-centered radicals using X-band ESR spectroscopy and then describes the detection of superoxide and hydroxyl radicals by the spin trap 5,5-dimethyl-1-pyrroline-N-oxide and ESR spectroscopy in the perfusate from isolated perfused rat livers subjected to ischemia/reperfusion. This article also reviews the current status of ESR for the in vivo detection of free radicals and in vivo imaging of exogenously administered free radicals. Moreover, we show that in vivo ESR-computed tomography with 3-carbamoyl-2,2,5, 5-tetramethylpyrrolidine-1-oxyl may be useful for noninvasive anatomical imaging and also for imaging of hepatic oxidative stress in vivo. 相似文献
103.
Aoyama Y Uenaka M Kii M Tanaka M Konoike T Hayasaki-Kajiwara Y Naya N Nakajima M 《Bioorganic & medicinal chemistry》2001,9(11):3065-3075
3-Benzylazetidine-2-one derivatives were designed and evaluated as a novel series of chymase inhibitors. Structure-activity relationship studies of 3-benzylazetidine-2-ones led to compounds 23, which exhibited 3.1 nM inhibition of human chymase and enhancement of stability in human plasma (t(1/2) 6h). 相似文献
104.
Miyuki Nishi Fumiyo Aoyama Fumihiko Kisa Hua Zhu Mingzhai Sun Peihui Lin Hiroya Ohta Bo Van Shinichiro Yamamoto Sho Kakizawa Hideki Sakai Jianjie Ma Akira Sawaguchi Hiroshi Takeshima 《The Journal of biological chemistry》2012,287(40):33523-33532
Of the TRIM/RBCC family proteins taking part in a variety of cellular processes, TRIM50 is a stomach-specific member with no defined biological function. Our biochemical data demonstrated that TRIM50 is specifically expressed in gastric parietal cells and is predominantly localized in the tubulovesicular and canalicular membranes. In cultured cells ectopically expressing GFP-TRIM50, confocal microscopic imaging revealed dynamic movement of TRIM50-associated vesicles in a phosphoinositide 3-kinase-dependent manner. A protein overlay assay detected preferential binding of the PRY-SPRY domain from the TRIM50 C-terminal region to phosphatidylinositol species, suggesting that TRIM50 is involved in vesicular dynamics by sensing the phosphorylated state of phosphoinositol lipids. Trim50 knock-out mice retained normal histology in the gastric mucosa but exhibited impaired secretion of gastric acid. In response to histamine, Trim50 knock-out parietal cells generated deranged canaliculi, swollen microvilli lacking actin filaments, and excess multilamellar membrane complexes. Therefore, TRIM50 seems to play an essential role in tubulovesicular dynamics, promoting the formation of sophisticated canaliculi and microvilli during acid secretion in parietal cells. 相似文献
105.
We previously substantiated that Ci-TK, a tachykinin of the protochordate, Ciona intestinalis (Ci), triggered oocyte growth from the vitellogenic stage (stage II) to the post-vitellogenic stage (stage III) via up-regulation of the gene expression and enzymatic activity of the proteases: cathepsin D, carboxypeptidase B1, and chymotrypsin. In the present study, we have elucidated the localization, gene expression and activation profile of these proteases. In situ hybridization showed that the Ci-cathepsin D mRNA was present exclusively in test cells of the stage II oocytes, whereas the Ci-carboxypeptidase B1 and Ci-chymotrypsin mRNAs were detected in follicular cells of the stage II and stage III oocytes. Double-immunostaining demonstrated that the immunoreactivity of Ci-cathepsin D was largely colocalized with that of the receptor of Ci-TK, Ci-TK-R, in test cells of the stage II oocytes. Ci-cathepsin D gene expression was detected at 2h after treatment with Ci-TK, and elevated for up to 5h, and then slightly decreased. Gene expression of Ci-carboxypeptidase B1 and Ci-chymotrypsin was observed at 5h after treatment with Ci-TK, and then decreased. The enzymatic activities of Ci-cathepsin D, Ci-carboxypeptidase B1, and Ci-chymotrypsin showed similar alterations with 1-h lags. These gene expression and protease activity profiles verified that Ci-cathepsin D is initially activated, which is followed by the activation of Ci-carboxypeptidase B1 and Ci-chymotrypsin. Collectively, the present data suggest that Ci-TK directly induces Ci-cahtepsin D in test cells expressing Ci-TK receptor, leading to the secondary activation of Ci-chymotrypsin and Ci-carboxypeptidase B1 in the follicle in the tachykininergic oocyte growth pathway. 相似文献
106.
Ken-ichi Itoh Kaoru Nakamura Tadashi Aoyama Ryusuke Matsuba Tsuyoshi Kakimoto Masahiko Murakami Rio Yamanaka Toshiya Muranaka Hiroshi Sakamaki Toshio Takido 《Biotechnology letters》2012,34(11):2083-2086
Aromatic ketones were reduced using suspension culture of Chlorella sp. MK201 under fluorescent light illumination producing the corresponding chiral alcohols in high yields with excellent enantiomeric excess (ee). For example, 2′,3′,4′,5′,6′-pentafluoroacetophenone at 0.25?mg/ml was converted to the corresponding (S)-alcohol in 80?% yield with?>99?% ee by 1?mg dry wt of Chlorella/ml in 12?h illumination (2,000 lux). 相似文献
107.
Inoue Y Hasegawa S Yamada T Date Y Mizutani H Nakata S Matsunaga K Akamatsu H 《Pigment cell & melanoma research》2012,25(3):299-311
Retinoic acid (RA) is considered to control melanocytes; however, its precise mechanism remains unclear because of a bimodal effect, which promotes or inhibits melanin synthesis depending on the cell type, culture condition of melanocytes and skin conditions. In this study, we examined the effects of RA throughout each stage of differentiation of melanocytes using a mouse embryonic stem cell culture system to induce melanocytes. The results showed that RA has significantly different effects depending on the stage of differentiation of melanocytes. More specifically, RA promoted differentiation in earlier stages, wherein embryonic stem cells became melanoblasts via neural crest cells, and inhibited differentiation in later stages, wherein melanoblasts became melanocytes. It was revealed for the first time that melanocytes show markedly different reactions to RA depending on the stage of differentiation. 相似文献
108.
Suzuki H Shibata R Kito T Yamamoto T Ishii M Nishio N Ito S Isobe K Murohara T 《PloS one》2012,7(6):e39562
Advanced age is associated with decreased stem cell activity. However, the effect of aging on the differentiation capacity of induced pluripotent stem (iPS) cells into cardiovascular cells has not been fully clarified. We investigated whether iPS cells derived from young and old mice are equally capable of differentiating into vascular progenitor cells, and whether these cells regulate vascular responses in vivo. iPS cells from mouse embryonic fibroblasts (young) or 21 month-old mouse bone marrow (old) were used. Fetal liver kinase-1 positive (Flk-1(+)) cells, as a vascular progenitor marker, were induced after 3 to 4 days of culture from iPS cells derived from young and old mice. These Flk-1(+) cells were sorted and shown to differentiate into VE-cadherin(+) endothelial cells and α-SMA(+) smooth muscle cells. Tube-like formation was also successfully induced in both young and old murine Flk-1(+) cells. Next, hindlimb ischemia was surgically induced, and purified Flk-1(+) cells were directly injected into ischemic hindlimbs of nude mice. Revascularization of the ischemic hindlimb was significantly accelerated in mice transplanted with Flk-1(+) cells derived from iPS cells from either young or old mice, as compared to control mice as evaluated by laser Doppler blood flowmetry. The degree of revascularization was similar in the two groups of ischemic mice injected with iPS cell-derived Flk-1(+) cells from young or old mice. Transplantation of Flk-1(+) cells from both young and old murine iPS cells also increased the expression of VEGF, HGF and IGF mRNA in ischemic tissue as compared to controls. iPS cell-derived Flk-1(+) cells differentiated into vascular progenitor cells, and regulated angiogenic vascular responses both in vitro and in vivo. These properties of iPS cells derived from old mice are essentially the same as those of iPS cells from young mice, suggesting the functionality of generated iPS cells themselves to be unaffected by aging. 相似文献
109.
Shinpei Murasawa Katsuya Iuchi Shinichi Sato Tomomi Noguchi-Yachide Mikiko Sodeoka Tsutomu Yokomatsu Kosuke Dodo Yuichi Hashimoto Hiroshi Aoyama 《Bioorganic & medicinal chemistry》2012,20(21):6384-6393
A structure consisting of substituted hydantoin linked to a 5-(halophenyl)furan-2-yl group via an amide bond was identified as a promising scaffold for development of low-molecular-weight therapeutic agents to treat vascular dysfunction, including ischemia/reperfusion injury. Among the compounds synthesized, 5-(3,5-dichlorophenyl)-N-{2,4-dioxo-3-[(pyridin-3-yl)methyl]imidazolidin-1-yl}-2-furamide (17) possessed the most potent inhibitory activity against Ca2+-induced mitochondrial swelling. The structural development, synthesis and structure–activity relationship of these compounds are described. 相似文献
110.
Yuko Ishizaki Mitsue Maru Hirohiko Higashino Shoko Katsumoto Kyoko Egawa Yoshitoki Yanagimoto Teruyo Nagahama 《BioPsychoSocial medicine》2012,6(1):1-4