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51.
Chie Tomikawa Takayuki Ohira Yasushi Inoue Takuya Kawamura Akihiko Yamagishi Tsutomu Suzuki Hiroyuki Hori 《FEBS letters》2013
Thermoplasma acidophilum is a thermo-acidophilic archaeon. We purified tRNALeu (UAG) from T. acidophilum using a solid-phase DNA probe method and determined the RNA sequence after determining via nucleoside analysis and m7G-specific aniline cleavage because it has been reported that T. acidophilum tRNA contains m7G, which is generally not found in archaeal tRNAs. RNA sequencing and liquid chromatography–mass spectrometry revealed that the m7G modification exists at a novel position 49. Furthermore, we found several distinct modifications, which have not previously been found in archaeal tRNA, such as 4-thiouridine9, archaeosine13 and 5-carbamoylmethyuridine34. The related tRNA modification enzymes and their genes are discussed. 相似文献
52.
Koji Ochiai Satoshi Takita Akihiko Kojima Tomohiko Eiraku Kazuhiko Iwase Tetsuya Kishi Akira Ohinata Yuichi Yageta Tokutaro Yasue David R. Adams Yasushi Kohno 《Bioorganic & medicinal chemistry letters》2013,23(1):375-381
(?)-6-(7-Methoxy-2-(trifluoromethyl)pyrazolo[1,5-a]pyridin-4-yl)-5-methyl-4,5-dihydropyridazin-3(2H)-one (KCA-1490) exhibits moderate dual PDE3/4-inhibitory activity and promises as a combined bronchodilatory/anti-inflammatory agent. N-alkylation of the pyridazinone ring markedly enhances potency against PDE4 but suppresses PDE3 inhibition. Addition of a 6-aryl-4,5-dihydropyridazin-3(2H)-one extension to the N-alkyl group facilitates both enhancement of PDE4-inhibitory activity and restoration of potent PDE3 inhibition. Both dihydropyridazinone rings, in the core and extension, can be replaced by achiral 4,4-dimethylpyrazolone subunits and the core pyrazolopyridine by isosteric bicyclic heteroaromatics. In combination, these modifications afford potent dual PDE3/4 inhibitors that suppress histamine-induced bronchoconstriction in vivo and exhibit promising anti-inflammatory activity via intratracheal administration. 相似文献
53.
Kentaro Takai Yasunao Inoue Yasuko Konishi Atsushi Suwa Yoshiharu Uruno Harumi Matsuda Tomokazu Nakako Mutsuko Sakai Hiroyuki Nishikawa Gakuji Hashimoto Takeshi Enomoto Atsushi Kitamura Yasuaki Uematsu Akihiko Kiyoshi Takaaki Sumiyoshi 《Bioorganic & medicinal chemistry letters》2013,23(16):4644-4647
We designed and synthesized N-substituted 8-azatetrahydroquinolone derivatives as selective M1 and M4 muscarinic acetylcholine receptors agonists. Optimization of selected derivatives led to the discovery of compound 7 as a highly potent M1 and M4 agonist with weak hERG inhibition. Oral administration of compound 7 improved psychosis-like behavior in rats. 相似文献
54.
Akihiko Kojima Satoshi Takita Tatsunobu Sumiya Koji Ochiai Kazuhiko Iwase Tetsuya Kishi Akira Ohinata Yuichi Yageta Tokutaro Yasue Yasushi Kohno 《Bioorganic & medicinal chemistry letters》2013,23(19):5311-5316
We previously identified KCA-1490 [(?)-6-(7-methoxy-2-trifluoromethyl-pyrazolo[1,5-a]pyridin-4-yl)-5-methyl-4,5-dihydro-3-(2H)-pyridazinone], a dual PDE3/4 inhibitor. In the present study, we found highly potent selective PDE4 inhibitors derived from the structure of KCA-1490. Among them, N-(3,5-dichloropyridin-4-yl)-7-methoxy-2-(trifluoromethyl)pyrazolo[1,5-a]pyridine-4-carboxamide (2a) had good anti-inflammatory effects in an animal model. 相似文献
55.
56.
Tateki Hayashi Akihiko Terao Shinji Ueda Mitsuo Namiki 《Bioscience, biotechnology, and biochemistry》2013,77(11):3139-3144
Ascorbic acid-protein mixtures of low moisture content stored for 2~3 days in aerobic conditions at 60°C produced a red coloration, which was shown to have resulted from an amino-carbonyl reaction of oxidized ascorbic acid (dehydroascorbic acid, DHA) by the facts that DHA-casein or ovalbumin systems yielded a rapid red coloration in low moisture conditions as well as in an ethanol suspension. Zein showed only a weak red coloration with DHA. An apparent decrease in the free amino group, as determined by the TNBS method, was observed to be associated in parallel with the red pigment formation. The electrophoretic pattern of ovalbumin changed significantly upon incubation with DHA, together with the formation of the red pigment. The red pigment extracted from a DHA-casein system showed an absorption spectrum, TLC Rf value, and hydrolyzed products (DHA and scorbamic acid) identical to those of 2,2′-nitrilo di-2(2)-deoxy-l-ascorbic acid mono ammonium salt, produced from DHA and amino acid. Formation of the red pigment was also observed in the reaction of DHA with Nα-acetyl lysine. These results indicate that the ε-amino group of lysine in protein can be attributed to the formation of a red pigment identical with NDA. 相似文献
57.
Yusuke Sakai Makiko Koike Hideko Hasegawa Kosho Yamanouchi Akihiko Soyama Mitsuhisa Takatsuki Tamotsu Kuroki Kazuo Ohashi Teruo Okano Susumu Eguchi 《PloS one》2013,8(7)
Cell sheet engineering is attracting attention from investigators in various fields, from basic research scientists to clinicians focused on regenerative medicine. However, hepatocytes have a limited proliferation potential in vitro, and it generally takes a several days to form a sheet morphology and multi-layered sheets. We herein report our rapid and efficient technique for generating multi-layered human hepatic cell (HepaRG® cell) sheets using pre-cultured fibroblast monolayers derived from human skin (TIG-118 cells) as a feeder layer on a temperature-responsive culture dish. Multi-layered TIG-118/HepaRG cell sheets with a thick morphology were harvested on day 4 of culturing HepaRG cells by forceful contraction of the TIG-118 cells, and the resulting sheet could be easily handled. In addition, the human albumin and alpha 1-antitrypsin synthesis activities of TIG-118/HepaRG cells were approximately 1.2 and 1.3 times higher than those of HepaRG cells, respectively. Therefore, this technique is considered to be a promising modality for rapidly fabricating multi-layered human hepatocyte sheets from cells with limited proliferation potential, and the engineered cell sheet could be used for cell transplantation with highly specific functions. 相似文献
58.
59.
Ryosuke Fujiwara Shuhei Noda Yoshifumi Kawai Tsutomu Tanaka Akihiko Kondo 《Biotechnology letters》2016,38(9):1543-1549
Objectives
To find a novel host for the production of 4-vinylphenol (4VPh) by screening Streptomyces species.Results
The conversion of p-coumaric acid (pHCA) to 4VPh in Streptomyces mobaraense was evaluated using a medium containing pHCA. S. mobaraense readily assimilated pHCA after 24 h of cultivation to produce 4VPh. A phenolic acid decarboxylase, derived from S. mobaraense (SmPAD), was purified following heterologous expression in Escherichia coli. SmPAD was evaluated under various conditions, and the enzyme’s kcat/Km value was 0.54 mM ?1 s?1. Using intergenetic conjugation, a gene from Rhodobacter sphaeroides encoding a tyrosine ammonia lyase, which catalyzes the conversion of l-tyrosine to p-coumaric acid, was introduced into S. mobaraense. The resulting S. mobaraense transformant produced 273 mg 4VPh l?1 from 10 g glucose l?1.Conclusion
A novel strain suitable for the production of 4VPh and potentially other aromatic compounds was isolated.60.
Kengo Sasaki Jun Inoue Daisuke Sasaki Namiko Hoshi Tomokazu Shirai Itsuko Fukuda Takeshi Azuma Akihiko Kondo Ro Osawa 《Biotechnology journal》2019,14(5)
Compositional alteration of the gut microbiota is associated with ulcerative colitis (UC). Here, a model culture system is established for the in vitro human colonic microbiota of UC, which will be helpful for determining medical interventions. 16S ribosomal RNA sequencing confirms that UC models are successfully developed from fecal inoculum and retain the bacterial species biodiversity of UC feces. The UC models closely reproduce the microbial components and successfully preserve distinct clusters from the healthy subjects (HS), as observed in the feces. The relative abundance of bacteria belonging to the family Lachnospiraceae significantly decreases in the UC models compared to that in HS, as observed in the feces. The system detects significantly lower butyrogenesis in the UC models than that in HS, correlating with the decreased abundance of Lachnospiraceae. Interestingly, the relative abundance of Lachnospiraceae does not correlate with disease activity (defined as partial Mayo score), suggesting that Lachnospiraceae persists in UC patients at a decreased level, irrespective of the alteration in disease activity. Moreover, the system shows that administration of Clostridium butyricum MIYAIRI restores butyrogenesis in the UC model. Hence, the model detects deregulation in the intestinal environment in UC patients and may be useful for simulating the effect of probiotics. 相似文献