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71.
Yoshihito Ueno Shinji Ishihara Yasutomo Ito Yukio Kitade 《Nucleosides, nucleotides & nucleic acids》2013,32(4-6):475-487
The synthesis and properties of oligonucleotides (ONs) containing 9-(2,3,4-trihydroxybutyl)adenine, A C2 and A C3, are described. The ON containing A C2 involves the 3′ → 4′ and 3′ → 5′ phosphodiester linkages in the strand, whereas that containing A C3 possesses the 3′ → 4′ and 2′ → 5′ phosphodiester linkages. It was found that incorporation of the analogs, A C2 or A C3, into ONs significantly reduces the thermal and thermodynamic stabilities of the ON/DNA duplexes, but does not largely decrease the thermal and thermodynamic stabilities of the ON/RNA duplexes as compared with the case of the ON/DNA duplexes. It was revealed that the base recognition ability of A C2 is greater than that of A C3 in the ON/RNA duplexes. 相似文献
72.
Motohiro Morioka † Kohji Fukunaga Shinji Nagahiro †Masahito Kurino Yukitaka Ushio †Eishichi Miyamoto 《Journal of neurochemistry》1995,64(5):2132-2139
Abstract: The exposure of cultured rat hippocampal neurons to 500 µ M glutamate for 20 min induced a 55% decrease in the total Ca2+ /calmodulin-dependent protein kinase II (CaM kinase II) activity. The Ca2+ -independent activity and autophosphorylation of CaM kinase II decreased to the same extent as the changes observed in total CaM kinase II activity, and these decreases in activities were prevented by pretreatment with MK-801, an N -methyl- d -aspartate (NMDA)-type receptor antagonist, and the removal of extracellular calcium but not by antagonists against other types of glutamate receptors and protease inhibitors. Similarly, the decrease in the CaM kinase II activity was induced by a Ca2+ ionophore, ionomycin. Immunoblot analysis with the anti-CaM kinase II antibody revealed a significant decrease in the amount of the enzyme in the soluble fraction, in contrast with the inverse increase in the insoluble fraction; thus, the translocation was probably induced during treatment of the cells with glutamate. These results suggest that glutamate released during brain ischemia induces a loss of CaM kinase II activity in hippocampal neurons, by stimulation of the NMDA receptor, and that inactivation of the enzyme may possibly be involved in the cascade of the glutamate neurotoxicity following brain ischemia. 相似文献
73.
Hidehiko Kondo Iichiro Shimomura Ken Kishida Hiroshi Kuriyama Yasunaka Makino Hitoshi Nishizawa Morihiro Matsuda Norikazu Maeda Hiroyuki Nagaretani Shinji Kihara Yoshihisa Kurachi Tadashi Nakamura Tohru Funahashi Yuji Matsuzawa 《European journal of biochemistry》2002,269(7):1814-1826
Aquaporin adipose (AQPap), which we identified from human adipose tissue, is a glycerol channel in adipocyte [Kishida et al. (2000) J. Biol. Chem. 275, 20896-20902]. In the current study, we determined the genomic structure of the human AQPap gene, and identified three AQPap-like genes that resembled (approximately 95%) AQPap, with little expression in human tissues. The AQPap promoter contained a putative peroxisome proliferator response element (PPRE) at -46 to -62, and a putative insulin response element (IRE) at -542/-536. Deletion of the PPRE abolished the pioglitazone-mediated induction of AQPap promoter activity in 3T3-L1 adipocytes. Deletion and single base pair substitution analysis of the IRE abolished the insulin-mediated suppression of the human AQPap gene. Analysis of AQPap sequence in human subjects revealed three missense mutations (R12C, V59L and G264V), and two silent mutations (A103A and G250G). The cRNA injection of the missense mutants into Xenopus oocytes revealed the absence of the activity to transport glycerol and water in the AQPap-G264V protein. In the subject homozygous for AQPap-G264V, exercise-induced increase in plasma glycerol was not observed in spite of the increased plasma noradrenaline. We suggest that AQPap is responsible for the increase of plasma glycerol during exercise in humans. 相似文献
74.
We have reported previously that recombinant human erythropoietin (rhEPO) produced from Sp2/0-Ag14 transformant had a low biological activity in vivo as compared with other human EPOs. rhEPO from SP2/0 has now been found to have a lower amount of sialic acid and different sugar chains from other hEPOs. This recombinant molecule contains disialobranches as major and complex sugar chains which showed broad peaks on gel-filtration chromatography. These differences may be responsible for its low in vivo bioactivity. 相似文献
75.
Isolation and characterization of thermotolerant bacterium utilizing ammonium and nitrate ions under aerobic conditions 总被引:1,自引:0,他引:1
Takenaka S Zhou Q Kuntiya A Seesuriyachan P Murakami S Aoki K 《Biotechnology letters》2007,29(3):385-390
A thermotolerant bacterium, identified as Bacillus licheniformis, completely utilized 0.1% (w/v) NH4NO3 at 30 and 50°C under aerobic condition. The addition of 0.5 mM Fe2+ to the NH4NO3 medium markedly promoted the utilization of NH4+ and NO3−. At 50°C, of total nitrogen originally provided, 24% was taken up into the cells and 20% remained in the culture supernatant.
Residual nitrogen (56%) was probably removed into the atmosphere. The cell extracts contained enzymes involved in denitrification.
GC-MS demonstrated that NH4 15NO3 had been converted to 15N2O. These results indicate that the strain has denitrification ability under aerobic condition. 相似文献
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80.
Hiroki Nakagawa Shinji Ishigami Kiyoshi Sekiguchi Kunio Kurata Nagao Ogura 《Phytochemistry》1981,20(6):1229-1230
Evidence is presented for the selective breakdown of altered tomato β-fructofuranosidase molecules by a neutral protease from Bacillus subtilis. 相似文献