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1.
Shuzo Miyamoto Yoshihiro Matsuda Shin-ichiro Sano Hiroshi Shiraki Hachro Nakagawa 《Neurochemical research》1992,17(7):723-727
The activity of ammoniagenesis from guanine nucleotides was found to increase significantly in rat brain after infusion of kainic acid into the striatum. Among the enzymes involved in degrading guanine nucleotides, nucleoside diphosphatase was markedly increased in the lesioned striatum. The enzyme activity began to increase 2 days after the infusion, and reached the maximum on the 13th day, the level being 4 times as high as that of the intact contralateral region. The increased activity was due to Type L enzyme, judging from its substrate specificity. Puromycin and cycloheximide inhibited this increase, indicating that the increased activity resulted from an increase in the net synthesis of the enzyme. These findings suggest that Type L NDPase might play some important roles in gliosis after neuronal lesion. 相似文献
2.
Close linkage of MEN2A with RBP3 locus in Japanese kindreds 总被引:7,自引:0,他引:7
Masayuki Yamamoto Shin-ichiro Takai Tetsuro Miki Kazuyoshi Motomura Makoto Okazaki Isamu Nishisho Hideo Tateishi Akira Miyauchi Tasuku Honjo A. J. Pakstis Takesada Mori 《Human genetics》1989,81(3):287-288
Summary The gene responsible for multiple endocrine neoplasia type 2A (MEN2A) has recently been assigned to the pericentromeric region of chromsome 10 in European Caucasian kindreds by linkage analysis using a DNA marker, interstitial retinol-binding protein 3 (RBP3). We have found tight linkage between the MEN2A and RBP3 loci in Japanese MEN2A kindreds. The maximum lod score is 5.19 at a recombination fraction of 0.00. This result suggests that mutation of a certain gene close to RBP3 is responsible for MEN2A irrespective of ethnic backgrounds. 相似文献
3.
A system for induction of synthesis of 相似文献
4.
Seiichi Tokura Yoshihiro Ikeuchi Shin-ichiro Nishimura Norio Nishi 《International journal of biological macromolecules》1983,5(4):249
A new type polyamide containing a glucose unit in the main chain has been synthesized by the polymerization of C1, C3, C4 blocked C6-carboxymethylglucosamine, prepared from chitin. The deblocking procedure gave the water-soluble polyamide, of MW 1.5 × 104, which can be regarded as a model for the recognition site of lectin. 相似文献
5.
Masashi Yamada Hiroshi Ohnishi Shin-ichiro Sano Toshiyuki Araki Atsushi Nakatani Toshihiko Ikeuchi & Hiroshi Hatanaka 《Journal of neurochemistry》1999,73(1):41-49
Shp2, a protein tyrosine phosphatase possessing SH2 domains, is utilized in the intracellular signaling of various growth factors. Shp2 is highly expressed in the CNS. Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, which also shows high levels of expression in the CNS, exerts neurotrophic and neuromodulatory effects in CNS neurons. We examined how BDNF utilizes Shp2 in its signaling pathway in cultured cerebral cortical neurons. We found that BDNF stimulated coprecipitation of several tyrosine-phosphorylated proteins with anti-Shp2 antibody and that Grb2 and phosphatidylinositol 3-kinase (PI3-K) were coprecipitated with anti-Shp2 antibody in response to BDNF. In addition, both anti-Grb2 and anti-PI3-K antibodies coprecipitated Shp2 in response to BDNF. The BDNF-stimulated coprecipitation of the tyrosine-phosphorylated proteins, Grb2, and PI3-K with anti-Shp2 antibody was completely inhibited by K252a, an inhibitor of TrkB receptor tyrosine kinase. This BDNF-stimulated Shp2 signaling was markedly sustained as well as BDNF-induced phosphorylation of TrkB and mitogen-activated protein kinases. In PC12 cells stably expressing TrkB, both BDNF and nerve growth factor stimulated Shp2 signaling similarly to that by BDNF in cultured cortical neurons. These results indicated that Shp2 shows cross-talk with various signaling molecules including Grb2 and PI3-K in BDNF-induced signaling and that Shp2 may be involved in the regulation of various actions of BDNF in CNS neurons. 相似文献
6.
Bo Zhang Akira Matsunaga David L. Rainwater Shin-ichiro Miura Keita Noda Hiroaki Nishikawa Yoshinari Uehara Kazuyuki Shirai Masahiro Ogawa Keijiro Saku 《Journal of lipid research》2009,50(9):1832-1841
Electronegative LDL, a charge-modified LDL (cm-LDL) subfraction that is more negatively charged than normal LDL, has been shown to be inflammatory. We previously showed that pravastatin and simvastatin reduced the electronegative LDL subfraction, fast-migrating LDL (fLDL), as analyzed by capillary isotachophoresis (cITP). The present study examined the effects of rosuvastatin on the more electronegative LDL subfraction, very-fast-migrating LDL (vfLDL), and small, dense charge-modified LDL (sd-cm-LDL) subfractions. Patients with hypercholesterolemia or those who were being treated with statins (n = 81) were treated with or switched to 2.5 mg/d rosuvastatin for 3 months. Rosuvastatin treatment effectively reduced cITP cm-LDL subfractions of LDL (vfLDL and fLDL) or sdLDL (sd-vfLDL and sd-fLDL), which were closely related to each other but were different from the normal subfraction of LDL [slow-migrating LDL (sLDL)] or sdLDL (sd-sLDL) in their relation to the levels of remnant-like particle cholesterol (RLP-C), apolipoprotein (apo) C-II, and apoE. The percent changes in cm-LDL or sd-cm-LDL caused by rosuvastatin were correlated with those in the particle concentrations of LDL or sdLDL measured as LDL-apoB or sdLDL-apoB and the levels of HDL-C, RLP-C, apoC-II, and apoE. In conclusion, rosuvastatin effectively reduced both the vfLDL subfraction and sd-cm-LDL subfractions as analyzed by cITP. 相似文献
7.
Koshiishi Yuichi Murata-Okubo Michiko Fujisawa Shin-ichiro Shimoi Gaku Hirayama Hiroki Kameyama Yuichi Souma Kousaku Wada Kenta 《Molecular biology reports》2020,47(4):2521-2527
Molecular Biology Reports - The emu (Dromaius novaehollandiae) is a useful poultry animal farmed for fat, meat, and eggs. Genetic structure and relationships among farmed emu populations in Japan... 相似文献
8.
Michihiro Ito Ikuo Sato Masumi Ishizaka Shin-ichiro Yoshida Motoo Koitabashi Shigenobu Yoshida Seiya Tsushima 《Applied and environmental microbiology》2013,79(5):1619-1628
Deoxynivalenol (DON) is a natural toxin of fungi that cause Fusarium head blight disease of wheat and other small-grain cereals. DON accumulates in infected grains and promotes the spread of the infection on wheat, posing serious problems to grain production. The elucidation of DON-catabolic genes and enzymes in DON-degrading microbes will provide new approaches to decrease DON contamination. Here, we report a cytochrome P450 system capable of catabolizing DON in Sphingomonas sp. strain KSM1, a DON-utilizing bacterium newly isolated from lake water. The P450 gene ddnA was cloned through an activity-based screening of a KSM1 genomic library. The genes of its redox partner candidates (flavin adenine dinucleotide [FAD]-dependent ferredoxin reductase and mitochondrial-type [2Fe-2S] ferredoxin) were not found adjacent to ddnA; the redox partner candidates were further cloned separately based on conserved motifs. The DON-catabolic activity was reconstituted in vitro in an electron transfer chain comprising the three enzymes and NADH, with a catalytic efficiency (kcat/Km) of 6.4 mM−1 s−1. The reaction product was identified as 16-hydroxy-deoxynivalenol. A bioassay using wheat seedlings revealed that the hydroxylation dramatically reduced the toxicity of DON to wheat. The enzyme system showed similar catalytic efficiencies toward nivalenol and 3-acetyl deoxynivalenol, toxins that frequently cooccur with DON. These findings identify an enzyme system that catabolizes DON, leading to reduced phytotoxicity to wheat. 相似文献
9.
Shin-ichiro Katsuda Hidefumi Waki Masao Yamasaki Tadanori Nagayama Hirotaka O-Ishi Kiyoaki Katahira Noboru Machida Masamitsu Hasegawa Tsuyoshi Shimizu 《Experimental Animals》2002,51(1):83-93
Postnatal changes in the rheological properties of the aortic wall were investigated in relation to morphological development of the wall in Sprague-Dawley (SD) rats at 3, 8 and 20 weeks old. The mechanical tensile characteristics of the longitudinal wall strip excised from the proximal thoracic aorta were assessed with stress-strain and stress-relaxation tests. Wall tension in the low and medium strain ranges was significantly lower in 3-week-old rats than in 8-week-old rats and in 8-week-old rats than in 20-week-old rats. Wall stress was significantly lower in 3-week-old rats than in 8- and 20-week-old rats mainly in the medium strain range, but was significantly greater in 3-week-old rats than in 8- and 20-week-old rats in the high strain range. The value of incremental elastic modulus at 3 weeks old was significantly smaller than that at 8 and 20 weeks old at a strain of 0.25 and significantly larger than that at 8 and 20 weeks old at a strain of 0.50. The value of relaxation strength at 5 min after the stretching was significantly greater at 3 weeks old than that at 8 and 20 weeks old. The wall was viscoelastic in the low and medium strain ranges at 3 weeks though large wall stress was generated in the high strain range. Histological investigation revealed that the smooth muscle layer, fine elastin fiber connecting thick elastin fibers and wall thickness were thin at 3 weeks old in comparison with those at 8 and 20 weeks old, though there was no significant difference in number of nuclei of the smooth muscle cells among the three age groups. Changes in the tensile characteristics of the wall reflected well those of the microstructure of the wall with growth. The rheological properties and microstructure of the aortic wall were close to maturation at 8 weeks in SD rats. 相似文献
10.
Yamada Y Yokoyama S Fukuda N Kidoya H Huang XY Naitoh H Satoh N Takakura N 《Biochemical and biophysical research communications》2007,353(1):182-188
Umbilical cord blood (CB) is a promising source for regeneration therapy in humans. Recently, it was shown that CB was a source of mesenchymal stem cells as well as hematopoietic stem cells, and further that the mesenchymal stem cells could differentiate into a number of cells types of mesenchymal lineage, such as cardiomyocytes (CMs), osteocytes, chondrocytes, and fat cells. Previously, we reported that brown adipose tissue derived cells (BATDCs) differentiated into CMs and these CMs could adapt functionally to repair regions of myocardial infarction. In this study, we examined whether CB mononuclear cells (CBMNCs) could effectively differentiate into CMs by coculturing them with BATDCs and determined which population among CBMNCs differentiated into CMs. The results show that BATDCs effectively induced CBMNCs that were non-hematopoietic stem cells (HSCs) (educated CB cells: e-CBCs) into CMs in vitro. E-CBCs reconstituted infarcted myocardium more effectively than non-educated CBMNCs or CD34-positive HSCs. Moreover, we found that e-CBCs after 3 days coculturing with BATDCs induced the most effective regeneration for impaired CMs. This suggests that e-CBCs have a high potential to differentiate into CMs and that adequate timing of transplantation supports a high efficiency for CM regeneration. This strategy might be a promising therapy for human cardiac disease. 相似文献