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61.
Masayoshi Oyama Ken-ichi Nakashima Tetsuro Kamiya Manami Haba Tetsuro Ito Hiroko Murata Toshiyuki Tanaka Tetsuo Adachi Munekazu Iinuma Takeshi Kinoshita 《Phytochemistry letters》2013,6(2):215-218
Two novel flavonoids, named meliflavones A (1) and B (2), were isolated from the leaves of Melicope triphylla (Lam.) Merr., along with thirteen known compounds (3–15). Four of the polymethoxyflavonoids bearing a prenyloxy (3-methylbut-2-enyloxy) function (1, 3–5) induced the expression of extracellular-superoxide dismutase (EC-SOD) in a human leukemic U937 cell-based assay. 相似文献
62.
Tetsuro Ito Kouko Nishiya Masayoshi Oyama Toshiyuki Tanaka Jin Murata Dedy Darnaedi Munekazu Iinuma 《Phytochemistry letters》2013,6(4):667-670
Two O-glucosides of resveratrol dimers, ampelopsin F-11b-O-β-glucopyranosides with enantiomeric aglycones [cordifoloside A (1) and cordifoloside B (2)] and an enantiomer of the aglycone [(?)-ampelopsin F] were isolated from the leaves of Shorea cordifolia (Dipterocarpaceae). These structures were identified on the basis of spectroscopic evidence and their absolute configurations were elucidated using circular dichroism data. This is the first report on oligostilbenoids that demonstrates the co-occurrence of diastereomeric O-glucosides with enantiomeric aglycones in this family. 相似文献
63.
Yosuke Iizumi Masakatsu Oishi Tomoyuki Taniguchi Wakana Goi Yoshihiro Sowa Toshiyuki Sakai 《PloS one》2013,8(8)
Flavonoids have been reported to inhibit tumor growth by causing cell cycle arrest. However, little is known about the direct targets of flavonoids in tumor growth inhibition. In the present study, we developed a novel method using magnetic FG beads to purify flavonoid-binding proteins, and identified ribosomal protein S9 (RPS9) as a binding partner of the flavonoid apigenin. Similar to treatment with apigenin, knockdown of RPS9 inhibited the growth of human colon cancer cells at the G2/M phase by downregulating cyclin-dependent kinase 1 (CDK1) expression at the promoter level. Furthermore, knockdown of RPS9 suppressed G2/M arrest caused by apigenin. These results suggest that apigenin induces G2/M arrest at least partially by directly binding and inhibiting RPS9 which enhances CDK1 expression. We therefore raise the possibility that identification of the direct targets of flavonoids may contribute to the discovery of novel molecular mechanisms governing tumor growth. 相似文献
64.
Applied Entomology and Zoology - Invasion by the Argentine ant Linepithema humile (Mayr) (Hymenoptera: Formicidae) causes the collapse of global ecosystems. Attempts to exterminate this invasive... 相似文献
65.
Toshiyuki Yamaguchi Romanus Edy Prabowo Yuu Ohshiro Takaki Shimono Diana Jones Hiroshi Kawai 《Biofouling》2013,29(4):325-333
The Titan Acorn barnacle, Megabalanus coccopoma, a native of the tropical eastern Pacific, has become established in the western Atlantic (Brazil and the northern Gulf of Mexico to the Carolinas), northwestern Europe and the western Indian Ocean (Mauritius), and therefore its dispersal capabilities are well known. This study reports its introduction to Japan and confirms its occurrence in Australia. In an attempt to determine the source of this introduction, phylogeographic techniques, involving cytochrome c oxidase I sequences of various widely separate populations of M. rosa and M. volcano, were utilized. No significant genetic differentiation or haplotype patterns between widely separated populations of each of the three species were found. Lack of such differentiation indicates recent geographical isolation and thus negates a null hypothesis predicting that the occurrence of one of more of these species in Australia was natural. 相似文献
66.
Probability is closely related to biological organization and adaptation to the environment. Living systems need to maintain their organizational order by producing specific internal events non-randomly, and must cope with the uncertain environments. These processes involve increases in the probability of favorable events for these systems by reducing the degree of uncertainty of events. Systems with this ability will survive and reproduce more than those that have less of this ability. Probabilistic phenomena have been deeply explored using the mathematical theory of probability since Kolmogorov's axiomatization provided mathematical consistency for the theory. However, the interpretation of the concept of probability remains both unresolved and controversial, which creates problems when the mathematical theory is applied to problems in real systems. In this article, recent advances in the study of the foundations of probability from a biological viewpoint are reviewed, and a new perspective is discussed toward a comprehensive theory of probability for understanding the organization and adaptation of living systems. 相似文献
67.
Kazuto Ishikawa Takashi Ohmori Hirokuni Miyamoto Toshiyuki Ito Yoshifumi Kumagai Masatoshi Sonoda Jirou Matsumoto Hisashi Miyamoto Hiroaki Kodama 《Applied microbiology and biotechnology》2013,97(3):1349-1359
NO 3 ? is a major nitrogen source for plant nutrition, and plant cells store NO 3 ? in their vacuoles. Here, we report that a unique compost made from marine animal resources by thermophiles represses NO 3 ? accumulation in plants. A decrease in the leaf NO 3 ? content occurred in parallel with a decrease in the soil NO 3 ? level, and the degree of the soil NO 3 ? decrease was proportional to the compost concentration in the soil. The compost-induced reduction of the soil NO 3 ? level was blocked by incubation with chloramphenicol, indicating that the soil NO 3 ? was reduced by chloramphenicol-sensitive microbes. The compost-induced denitrification activity was assessed by the acetylene block method. To eliminate denitrification by the soil bacterial habitants, soil was sterilized with γ irradiation and then compost was amended. After the 24-h incubation, the N2O level in the compost soil with presence of acetylene was approximately fourfold higher than that in the compost soil with absence of acetylene. These results indicate that the low NO 3 ? levels that are often found in the leaves of organic vegetables can be explained by compost-mediated denitrification in the soil. 相似文献
68.
Masaki Setoguchi Shin Iimura Yuuichi Sugimoto Yoshiyuki Yoneda Jun Chiba Toshiyuki Watanabe Fumihito Muro Yutaka Iigo Gensuke Takayama Mika Yokoyama Tomoe Taira Misato Aonuma Tohru Takashi Atsushi Nakayama Nobuo Machinaga 《Bioorganic & medicinal chemistry》2013,21(1):42-61
We have carried out the optimization of substituents at the C-3 or the C-5 position on the pyrrolidine ring of VLA-4 antagonist 3 with 2-(phenylamino)-7-fluorobenzoxazolyl moiety for the purpose of improving in vivo efficacy while maintaining good aqueous solubility. As a result, we successfully increased in vitro activity in the presence of 3% human serum albumin and achieved an exquisite lipophilic and hydrophilic balance of compounds suitable for oral administrative regimen. The modification resulted in the identification of zwitterionic compound 7n with (5S)-[methoxy(methyl)amino]methylpyrrolidine, which significantly alleviated bronchial hyper-responsiveness to acetylcholine chloride at 12.5 mg/kg, p.o. in a murine asthma model and showed favorable aqueous solubility (JP1, 89 μg/mL; JP2, 462 μg/mL). Furthermore, this compound showed good oral bioavailability (F = 54%) in monkeys. 相似文献
69.
DNA-synthesis stimulatory activity was found in some tryptic fragments of human /¡-casein by using BALB/c3T3 cells, and two of them were identified as the /¡-casein fragments of Arg[l] to Lys[18] (/¡-CN(f 1 -18)) and of Gln[105] to Lys[l 17] (/¡-CN(fl05 -117)). 相似文献
70.
Ikuo Matsui Toshiyuki Kameyama Kunio Oishi Ko Aida 《Bioscience, biotechnology, and biochemistry》2013,77(3):833-835
The inhibitory effects of 3-nitro-2,4,6-trihydroxybenzamide derivatives on human 5-lipoxygenase (5-LO), a key enzyme in arachidonic acid cascades, were examined using 5-LO produced by Escherichia coli. Some of the tested compounds inhibited the conversion of arachidonic acid to 5-hydroperoxy-6,8,11,14-eicosatetraenoic acid (5-HPETE), and in particular the N-phenylbutyl derivative was about 30 times more active (IC50 = 35 μm) than caffeic acid (IC50 = 1000 μm), a known selective 5-LO inhibitor. 相似文献