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41.
Eriko Kudo Manabu Taura Kouki Matsuda Masako Shimamoto Ryusho Kariya Hiroki Goto Shinichiro Hattori Shinya Kimura Seiji Okada 《Bioorganic & medicinal chemistry letters》2013,23(3):606-609
The anti-HIV-1 activity of GUT-70, a natural product derived from the stem bark of Chlophyllum brasiliense, was evaluated. GUT-70 inhibited HIV-1 replication in both acutely and chronically infected cells through suppression of NF-κB. Our results strengthen the idea that NF-κB pathway is one of the potential targets to control HIV-1 replication and that GUT-70 could serve as a lead compound to develop novel therapeutic agents against HIV-1 infection. 相似文献
42.
Prostaglandins are biologically active substances used in a wide range of medical treatments. Prostaglandins have been supplied mainly by chemical synthesis; nevertheless, the high cost of prostaglandin production remains a factor. To lower the cost of prostaglandin production, we attempted to produce prostaglandins using a liverwort, Marchantia polymorpha L., which accumulates arachidonic acid, which is known as a substrate of prostaglandins. Here we report the first bioproduction of prostaglandins in plant species by introducing a cyclooxygenase gene from a red alga, Gracilaria vermiculophylla into the liverwort. The transgenic liverworts accumulated prostaglandin F2α, prostaglandin E2 and prostaglandin D2 which were not detected in the wild-type liverwort. Moreover, we succeeded in drastically increasing the bioproduction of prostaglandins using an in vitro reaction system with the extracts of transgenic liverworts. 相似文献
43.
Kenzo Kaifu Sachie Miyazaki Jun Aoyama Shingo Kimura Katsumi Tsukamoto 《Environmental Biology of Fishes》2013,96(4):439-446
The diet of Japanese eels, Anguilla japonica, was investigated using stomach content and stable isotope analyses. Stable isotope enrichment of carbon and nitrogen (Δδ13C and Δδ15N) was first estimated for A. japonica by comparing the isotopic signatures (δ13C and δ15N) of reared eels to that of their food. The estimated isotope enrichment was then applied to the diet estimation of A. japonica in the Kojima Bay-Asahi River system, Japan, combined with conventional stomach content analysis. Stable isotope enrichment varied among tissues, from 0.2‰ to 0.8‰ for carbon and from 1.3‰ to 2.1‰ for nitrogen. Nitrogen isotope enrichment of A. japonica muscle estimated in this study was 2.1‰, which was different from the previously reported mean δ15N enrichment of several animals of 3.4‰. These results indicate that isotope-based diet estimations for A. japonica need to use species- and tissue-specific values of isotope enrichment. In the diet analysis, stomach contents and stable isotopes revealed that (1) A. japonica appear to usually feed on a single type of prey species in each feeding session, (2) principal prey species were mud shrimp, Upogebia major, in brackish Kojima Bay and crayfish, Procambarus clarkia, in the Asahi River, (3) A. japonica in Kojima Bay primarily depend on the pelagic food web as a carbon source due to mud shrimp being filter feeders and eels in the Asahi River primarily depend on the littoral food web. Based on these results and the recently reported eel movements between Kojima Bay and the Asahi River, it appears that A. japonica can adapt to various feeding environments as opportunists, but also utilize the food resources by targeting a single type of prey species during a single feeding session. 相似文献
44.
Masakazu Goto Chisato Ito Mohammed Sani Yahaya Yoshihito Wakai Shiro Asano Yukari Oka 《Marine and Freshwater Behaviour and Physiology》2013,45(2):99-107
The number of microorganisms in the hindgut of dugongs (Dugong dugon) were estimated and their in vitro volatile fatty acid (VFA) production and degradation of eelgrass measured. Scanning electron microscopy showed that some rod bacteria attached to the surface of plant tissue degraded and eroded the cell walls. Number of starch-, lactate-, cellobiose-, pectin-, xylan- and cellulose-utilizing bacteria, sulfate-reducing bacteria and methane-producing bacteria were estimated at 109 ~ 1010 colony forming units g?1. Microorganisms degraded the cellulose and noncellulolytic components of the eelgrass, and about 47.3% of dry matter was degraded after 36?h in vitro incubation. The total VFA concentration was 10.5?mmol?dL?1 at 36?h incubation, which included 55.7?mol% acetate, 18.0?mol% n-butyrate and 15.1?mol% propionate. The gas composition of in vitro fermentation was 68.4% carbon dioxide, 22.2% methane and 9.4% hydrogen. 相似文献
45.
46.
Masato Hayakawa Tatsuya Ohyama Yoko Yamaguchi Shingo Iwabuchi Tomohiko Nakagawa Tamie Nakajima 《Molecular simulation》2013,39(9):644-656
To elucidate the specific interactions between the peroxisome proliferator-activated receptor (PPARα) and ligand GW409544 (GW), we obtained the solvated structures of the PPARα+GW complexes for human, mouse and rat by classical molecular mechanics calculations, and investigated their electronic properties by ab initio fragment molecular orbital calculations. The results indicate that the positively charged amino acids (Lys and Arg) of PPARα make a major contribution to the binding between PPARα and GW. In addition, it was clarified that Ser280 and Tyr314 of human and rat PPARα have a large attractive interaction with GW, while Ser280, Tyr314 and His440 of mouse PPARα have large interaction. These results on the difference in specific interactions between human and mouse/rat PPARα will be useful for predicting the effects of new chemicals on the human body based on the biomedical studies for the experimental animals such as mouse and rat. 相似文献
47.
Shizuko Yamaguchi Tomoko Yoshikawa Shingo Ikeda Tsunehiko Ninomiya 《Bioscience, biotechnology, and biochemistry》2013,77(7):797-802
Taste effects of six newly synthesized ribonucleotide derivatives, i.e., disodium salts of 2-methyl-5′-inosinic acid · 6H2O, 2-ethyl-5′-inosinic acid · 1.5H2O, 2-N-methyl-5′-guanylic acid · 5.5H2O, 2-N-dimethyl-5′-guanylic acid · 2.5H2O, 2-methylthio-5′-inosinic acid · 6H2O and 2-ethylthio-5′-inosinic acid · 2H2O, were studied. Stimulus thresholds (detection thresholds) of these derivatives ranged from about 0.02 to 0.006 g/100ml. Flavor-enhancing activities of them were 2.3 to 8.0 times larger than that of disodium 5′-inosinate · 7.5H2O IMP) in the synergistic effect with monosodium glutamate. Furthermore, the quality of taste of all the derivatives was recognized to be the same kind to that of IMP. 相似文献
48.
Several 4-thiazolone derivatives were synthesized by condensation of appropriate aryl cyanide and ethyl thioglycolate (or derivative), and factors affecting to the reaction rate are discussed. Keto-enol tautomerization of the 4-thiazolones is briefly discussed. 相似文献
49.
50.
Ryosuke Tateishi Shuichiro Shiina Masaaki Akahane Jiro Sato Yuji Kondo Ryota Masuzaki Hayato Nakagawa Yoshinari Asaoka Tadashi Goto Kuni Otomo Masao Omata Haruhiko Yoshida Kazuhiko Koike 《PloS one》2013,8(4)