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81.
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83.
Kazuyuki Nakamura Hirofumi Kodera Tenpei Akita Masaaki Shiina Mitsuhiro Kato Hideki Hoshino Hiroshi Terashima Hitoshi Osaka Shinichi Nakamura Jun Tohyama Tatsuro Kumada Tomonori Furukawa Satomi Iwata Takashi Shiihara Masaya Kubota Satoko Miyatake Eriko Koshimizu Kiyomi Nishiyama Mitsuko Nakashima Yoshinori Tsurusaki Noriko Miyake Kiyoshi Hayasaka Kazuhiro Ogata Atsuo Fukuda Naomichi Matsumoto Hirotomo Saitsu 《American journal of human genetics》2013
84.
Takaaki Kubota Yuichiro Ishiguro Azusa Takahashi-Nakaguchi Jane Fromont Tohru Gonoi Jun’ichi Kobayashi 《Bioorganic & medicinal chemistry letters》2013,23(1):244-247
Three new polyketides, manzamenones L–N (1–3), have been isolated from an Okinawan marine sponge of the genus Plakortis. The structures of 1–3 were elucidated on the basis of spectroscopic data. Manzamenones L–N (1–3) were new dimeric fatty-acid derivatives consisting of a tetrahydroindenone with three carboxy groups and two hexadecanyl chains. Manzamenones M (2) and N (3) showed antimicrobial activity against several bacteria and fungi. 相似文献
85.
Yohei Takahashi Takaaki Kubota Sunao Yamamoto Jun’ichi Kobayashi 《Bioorganic & medicinal chemistry letters》2013,23(1):117-118
Metachromins are a series of sesquiterpenoid quinones isolated from Okinawan marine sponges. Inhibitory effects of metachromins L–Q (1–6), sesquiterpenoid quinones with an amino acid residue, and their related analogs (7–18) prepared from metachromins A (19) and C (20) against receptor tyrosine kinases EGFR and HER2 were investigated. Two analogs 11 and 12 showed relatively stronger inhibitory activity against EGFR, while metachromins L–Q (1-6) and seven analogs (8, 10, 11, and 15–18) showed inhibitory activities against HER2. 相似文献
86.
Yoshiro Kinoshita Michinori Misaka Shuhei Kubota Hisao Ishikawa 《Bioscience, biotechnology, and biochemistry》2013,77(11):1975-1981
A mixture of two thionocarbamates was subjected to the acid-catalyzed rearrangement. A sample of the reaction mixture was analyzed by glpc and resolved into four components. From the cross-over result, it has been concluded that the acid-catalyzed rearrangement of alkyl thionocarbamates into the isomeric thiolcarbamates proceeds by an intermolecular alkylating mechanism. This conclusion was supported by the detection of a transalkylated intermediate. 相似文献
87.
Kimiko Anno Hisako Terahata Yutsuki Hayashi Nobuko Seno 《Bioscience, biotechnology, and biochemistry》2013,77(5):495-499
A highly purified fucoidin was isolated from Pelvetia wrightii by an improved method, which involves the removal of alginate with calcium chloride solution and purification with cetylpyridinium chloride (CPC).To this end, the critical salt concentrations of the cetylpyridinium complex of alginic acid and fucoidin in salt solutions (KCl, NaCl, CaCl2) were determined.The fucoidin of this alga contained both fucose and galactose as its constituents, in a ratio of approximately 10:1, and it is considered to be a galactofucan sulfate. 相似文献
88.
Kenji Kano Tomonori Konse Motoko Okada Tanekazu Kubota Sachiko Ibe Tokuji Ikeda 《Bioscience, biotechnology, and biochemistry》2013,77(7):1795-1800
A polarographic method based on the Brdi?ka current (the polarographic catalytic hydrogen evolution current produced by proteins in the presence of cobalt salts) was applied to direct titration of subtilisin BPN′ (S.BPIST) with plasminostreptin (PS) at a concentration level of 10”8 m. The first and second dissociation constants of the S.BPN-PS complex were determined by fitting theoretical curves to the titration data, in which the multiple equilibria involving microscopically distinct forms of S.BPN-PS complex were taken into account. The intrinsic free energy change in the first binding of S.BPN′ to dimeric PS was larger than that in the second binding. The dependence of the microscopic dissociation constants of S.BPN′-PS complex on pH indicates the participation of ionizable groups of pKa 8.0 and 9.4 in the complex formation. The repulsive effect between negatively charged molecules of S.BPN′ and PS in the complex formation at elevated pH is suggested. 相似文献
89.
Kenji Kobata Ikue Takemura Gaku Tago Takayuki Moriya Kaori Kubota Sachie Nakatani 《Bioscience, biotechnology, and biochemistry》2013,77(7):1242-1245
Long-chain N-vanillyl-acylamides (LCNVAs) were generated from plant oils and vanillylamine (VA) by nucleophilic amidation without any catalytic reagents. The resulting LCNVAs varied according to the fatty acid composition of the plant oil used. Therefore, the LCNVAs contained in Capsicum oleoresins were products that were spontaneously generated from the oleoresin during storage. 相似文献
90.
Jun Shimizu Takao Kubota Erika Takada Kenji Takai Naruyoshi Fujiwara Nagisa Arimitsu Yuji Ueda Sueshige Wakisaka Tomoko Suzuki Noboru Suzuki 《PloS one》2016,11(4)
Gut microbiota compositional alteration may have an association with immune dysfunction in patients with Behcet’s disease (BD). We conducted a fecal metagenomic analysis of BD patients. We analyzed fecal microbiota obtained from 12 patients with BD and 12 normal individuals by sequencing of 16S ribosomal RNA gene. We compared the relative abundance of bacterial taxa. Direct comparison of the relative abundance of bacterial taxa demonstrated that the genera Bifidobacterium and Eggerthella increased significantly and the genera Megamonas and Prevotella decreased significantly in BD patients compared with normal individuals. A linear discriminant analysis of bacterial taxa showed that the phylum Actinobacteria, including Bifidobacterium, and the family Lactobacillaceae exhibited larger positive effect sizes than other bacteria in patients with BD. The phylum Firmicutes and the class Clostridia had large effect sizes in normal individuals. There was no significant difference in annotated species numbers (as numbers of operational taxonomic unit; OTU) and bacterial diversity of each sample (alpha diversity) between BD patients and normal individuals. We next assigned each sample to a position using three axes by principal coordinates analysis of the OTU table. The two groups had a significant distance as beta diversity in the 3-axis space. Fecal sIgA concentrations increased significantly in BD patients but did not correlate with any bacterial taxonomic abundance. These data suggest that the compositional changes of gut microbes may be one type of dysbiosis (unfavorable microbiota alteration) in patients with BD. The dysbiosis may have an association with the pathophysiology of BD. 相似文献