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251.
Shuji Kitagawa Hiroko Fujisawa Fujio Kametani Hiromu Sakurai 《Free radical research》1992,15(6):319-324
Generation of active oxygen species by bovine blood platelets was examined by the electron spin resonance (ESR) spin trapping technique with 5,5-dimethyl-l-pyroline-l-oxide (DMPO). The hydroxyl spin-trapped adduct 5,5-dimethyl-2-hydroxy-l-pyrolidinyloxy (DMPO-OH) was formed in the presence of platelets, indicating the generation of hydroxyl radicals (· OH) by the platelets. Generation of · OH was observed even with platelets in the resting state, but was markedly enhanced when the platelets were activated with stimulants. Stronger stimulants such as the calcium ionophore ionomycin, induced greater radical gener-ation than the weaker stimulant ADP. When the platelets were stimulated by thrombin, generation of · OH was greatest after l.5 min, and depended on the dose of the stimulant. It was inhibited by inhibitors of platelet activation such as forskolin and phenolic antioxidants. 相似文献
252.
Daiki Hayashi Shuji Ueda Minoru Yamanoue Hitoshi Ashida 《Bioscience, biotechnology, and biochemistry》2018,82(1):65-73
Diabetic nephropathy (DN) is a diabetic vascular complication, and abnormal protein kinase C (PKC) activation from increased diacylglycerol (DG) production in diabetic hyperglycemia is one of the causes of DN. Diacylglycerol kinase (DGK) converts DG into phosphatidic acid. In other words, DGK can attenuate PKC activity by reducing the amount of DG. Recently, we reported that intraperitoneally administered d-α-tocopherol (vitamin E, αToc) induces an amelioration of DN in vivo through the activation of DGKα and the prevention of podocyte loss. However, the effect of the oral administration of αToc on DN in mice remains unknown. Here, we evaluated the effect of oral administration of αToc on DN and its molecular mechanism using streptozocin-induced diabetic mice. Consequently, the oral administration of αToc significantly ameliorated the symptoms of DN by preventing the loss of podocytes, and it was revealed that the inhibition of PKC?activity was involved in this amelioration. 相似文献
253.
Mizuki Yamada Tsutomu Takahashi Mai Hasegawa Mio Matsumura Kanna Ono Ryota Fujimoto Yuki Kitamura Yuki Murata Naoki Kakusawa Motohiro Tanaka Tohru Obata Yasuyuki Fujiwara Shuji Yasuike 《Bioorganic & medicinal chemistry letters》2018,28(2):152-154
Trisubstituted 5-organostibano-1H-1,2,3-triazoles (3a–f) were synthesized by the Cu-catalyzed azide-alkyne cycloaddition of various ethynylstibanes (1) with benzylazide (2) in the presence of CuBr (5 mol%) under aerobic conditions. The reaction of 5-stibanotriazoles with HCl afforded C5-unsubstituted 1,2,3-triazoles (4a–f). The antitumor activity of trisubstituted 5-organostibano-1H-1,2,3-triazoles (3a–f) and their 5-unsubstituted 1,2,3-triazoles (4a–f) were evaluated in several tumor cell lines. All 5-stibanotriazoles (3a–f) exerted an excellent antitumor activity. On the contrary, 5-unsubstituted 1,2,3-triazoles (4a–f) without a diphenylantimony group in the molecule exhibited very low antitumor activity compared with 5-stibanotriazoles (3a–f). In compounds of both the series, the substituted 4-butyl group appeared to decrease antitumor activity. However, results suggested that organometal (antimony) in the molecule was required for greater antitumor activity. In addition, all 5-stibanotriazoles (3a–f), but not all 5-unsubstituted 1,2,3-triazoles (4a–f), exhibited cytotoxicity in normal vascular endothelial cells derived from bovine aorta. Among the compounds (3b–e) that exhibited excellent antitumor activity, those with 4-methylphenyl (3b) and 1-cyclohexenyl (3e) showed relatively low cytotoxicity to vascular endothelial cells. Together, these results suggest that trisubstituted 5-organostibano-1H-1,2,3-triazoles, including compounds 3b and 3e, may serve as potential anticancer therapeutic drugs in the future. 相似文献
254.
Tomas Smejkal Shuji Hachisu James N. Scutt Nigel J. Willetts Danielle Sayer Laura Wildsmith Sophie Oliver Caroline Thompson Michel Muehlebach 《Bioorganic & medicinal chemistry letters》2018,28(3):339-343
Novel 2-aryl-cyclic-1,3-diones containing a 5-methoxy-[1,2,5]triazepane unit were explored towards an effective and wheat safe control of grass weeds. Their preparation builds on the ease of synthetic access to 7-membered heterocyclic [1,2,5]triazepane building blocks. Substitution and pattern hopping in the phenyl moiety revealed structure–activity relationships in good agreement with previously disclosed observations amongst the pinoxaden family of acetyl-CoA carboxylase inhibitors. In light of basic physicochemical, enzyme inhibitory and binding site properties, the N-methoxy functionality effectively acts as a bioisostere of the ether group in the seven-membered hydrazine ring. 相似文献
255.
Nathan Mise Takashi Sado Masako Tada Shuji Takada Nobuo Takagi 《Experimental cell research》1996,223(2):193
Mouse embryonal carcinoma (EC) cell lines are divided into two classes with or without the capability of reactivating the inactive X chromosome from a fusion partner of female lymphocyte. The 5′ region ofXistwas partially methylated in reactivating-competent EC cells but was fully methylated in reactivating-incompetent EC cells having a single X chromosome. Partial or heterogeneous methylation implies methylation of each CpG site in about half of the cell independently of methylation status of neighboring CpG sites. Fusion of the reactivating-competent EC cells with female lymphocytes induced not onlyde novomethylation in the 5′ region ofXistallele on the hitherto inactivated X chromosome, but also demethylation of the same region ofXiston the other X chromosome from the female somatic cell. In contrast, no such changes occurred in hybrid cells involving reactivating-incompetent EC cells. Thus, partial methylation of the 5′ region ofXistmost probably maintained by low maintenance and highde novomethylation efficiency is correlated with reactivation potential of the EC cell. It is possible that this unique methylation pattern is implicated in random X inactivation in EC-hybrid cellsin vitroand in epiblast cellsin vivo. 相似文献
256.
Masaki Fujita Tatsuya Morooka Shuji Fujimoto Tetsuhiro Moriya Kazunobu Amako 《Archives of microbiology》1995,164(6):444-447
Chromosomal DNA of 27 strains of Campylobacter fetus was analyzed by Southern blotting with a probe of the conserved region of sapA. The probe hybridized with 23 strains that produced type A lipopolysaccharide. These strains had more than six sapA homologs. In Southern blots of SalI-digested chromosomal DNA separated by pulsed-field gel electrophoresis, one fragment from 19 strains and two fragments from
4 strains hybridized. These data indicate that multiple sapA homologs are localized to a limited region on the chromosomal DNA of C. fetus and thus suggest the possibility of developing a typing system using this method.
Received: 28 June 1995 / Accepted: 19 September 1995 相似文献
257.
Yasuo Morimoto Ziro Nambu Isamu Tanaka Toshiaki Higashi Hiroshi Yamato Hajime Hori Shuji Cho Masamitsu Kido 《Biological trace element research》1995,48(3):287-296
To evaluate the effect of green nickel oxide (NiO) on the production of tumor necrosis factor (TNF) by alveolar macrophages,
alveolar macrophages were exposed to NiO in vitro and in vivo. For the in vitro study, rats alveolar macrophages were incubated
with NiO on a microplate for 24 h. TNF activity in the culture supernatant was determined by the L929 bioassay. Rats alveolar
macrophages cultured with 100 and 200 μg/mL of NiO in vitro induced the production of TNF, however, it was not statistically
significant compared with the control that was free from NiO exposure. For exposure in vivo, rats were divided into two groups.
Five were exposed to a daily concentration of 11.7±2.0 mg/m3 of NiO for an 8-hr/d, 5 d/wk, for 4 wk, and five rats (control) were kept in a cage and not exposed to NiO. Bronchoalveolar
lavage was performed and the recovered alveolar macrophages were incubated on a microplate for 24 h. TNF production by exposed
alveolar macrophages was significantly higher than that of controls. 相似文献
258.
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260.
Nanthawan Mekha Natteewan Poonwan Dr. Yuzuru Mikami Katsukiyo Yazawa Tohru Gonoi Shuji Hasegawa Kazuko Nishimura 《Mycoscience》1997,38(2):97-100
Results of random amplified polymorphic DNA (RAPD) analysis using three different primers showed that 16 strains ofPenicillium marneffei isolated from AIDS patients in Thailand belonged to a genetically homogenous group, but different slightly from an isolate
from bamboo rat in China. Six PCR fragments (from about, 200 to 600 bp) that were commonly observed in the RAPD fingerprint
of all strains were extracted and sequented. Usefulness of this sequence information for identification ofP. marneffei is discussed. 相似文献