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排序方式: 共有394条查询结果,搜索用时 15 毫秒
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Renato M Salgado Luciane P Capelo Rodolfo R Favaro Jocelyn D Glazier John D Aplin Telma MT Zorn 《Reproductive biology and endocrinology : RB&E》2009,7(1):60
Background
Remodeling of the extracellular matrix is one of the most striking features observed in the uterus during the estrous cycle and after hormone replacement. Versican (VER) is a hyaluronan-binding proteoglycan that undergoes RNA alternative splicing, generating four distinct isoforms. This study analyzed the synthesis and distribution of VER in mouse uterine tissues during the estrous cycle, in ovariectomized (OVX) animals and after 17beta-estradiol (E2) and medroxyprogesterone (MPA) treatments, either alone or in combination. 相似文献54.
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Masayuki Tamura Yukiko Tsuji Tatsuya Kusunose Atsushi Okazawa Naofumi Kamimura Tetsuya Mori Ryo Nakabayashi Shojiro Hishiyama Yuki Fukuhara Hirofumi Hara Kanna Sato-Izawa Toshiya Muranaka Kazuki Saito Yoshihiro Katayama Masao Fukuda Eiji Masai Shinya Kajita 《Applied microbiology and biotechnology》2014,98(19):8165-8177
Pinoresinol reductase and pinoresinol/lariciresinol reductase play important roles in an early step of lignan biosynthesis in plants. The activities of both enzymes have also been detected in bacteria. In this study, pinZ, which was first isolated as a gene for bacterial pinoresinol reductase, was constitutively expressed in Arabidopsis thaliana under the control of the cauliflower mosaic virus 35S promoter. Higher reductive activity toward pinoresinol was detected in the resultant transgenic plants but not in wild-type plant. Principal component analysis of data from untargeted metabolome analyses of stem, root, and leaf extracts of the wild-type and two independent transgenic lines indicate that pinZ expression caused dynamic metabolic changes in stems, but not in roots and leaves. The metabolome data also suggest that expression of pinZ influenced the metabolisms of lignan and glucosinolates but not so much of neolignans such as guaiacylglycerol-8-O-4′-feruloyl ethers. In-depth quantitative analysis by liquid chromatography–tandem mass spectrometry (LC-MS/MS) indicated that amounts of pinoresinol and its glucoside form were markedly reduced in the transgenic plant, whereas the amounts of glucoside form of secoisolariciresinol in transgenic roots, leaves, and stems increased. The detected levels of lariciresinol in the transgenic plant following β-glucosidase treatment also tended to be higher than those in the wild-type plant. Our findings indicate that overexpression of pinZ induces change in lignan compositions and has a major effect not only on lignan biosynthesis but also on biosynthesis of other primary and secondary metabolites. 相似文献
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Kenji Takahashi Naofumi Kamimura Shojiro Hishiyama Hirofumi Hara Daisuke Kasai Yoshihiro Katayama Masao Fukuda Shinya Kajita Eiji Masai 《Biodegradation》2014,25(5):735-745
Sphingobium sp. strain SYK-6 is capable of degrading various lignin-derived biaryls. We determined the catabolic pathway of a phenylcoumaran-type compound, dehydrodiconiferyl alcohol (DCA) in SYK-6, and identified some of the DCA catabolism genes. In SYK-6 cells, the alcohol group of DCA was oxidized to the carboxyl group, first at the B-ring side chain and then at the A-ring side chain. The resultant metabolite was degraded to 5-formylferulate and vanillin through the decarboxylation and the Cα–Cβ cleavage of the A-ring side chain. Based on the DCA catabolic pathway, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) genes are thought to be involved in the conversion of DCA into an aldehyde intermediate (DCA-L) and the conversion of DCA-L into a carboxylic acid intermediate (DCA-C), respectively. SLG_05620 and SLG_24930, which belong to quinohemoprotein ADH and aryl ADH, respectively, were isolated as the genes responsible for the oxidation of DCA. In addition to these genes, multiple genes similar to SLG_05620 and SLG_24930 were found to confer DCA oxidation activities on Escherichia coli cells. In order to identify the DCA-L dehydrogenase genes, the DCA-L oxidation activities of the SYK-6 gene products of putative twenty-one ALDH genes were examined. Significant activities were observed in the four ALDH gene products, including the SLG_27910 product, which showed the highest activity. The disruption of SLG_27910 caused a decreased conversion of DCA-L, suggesting that SLG_27910 plays an important role in the DCA-L oxidation. In conclusion, no specific gene seems to be solely responsible for the conversion of DCA and DCA-L, however, the multiple genes encoding quinohemoprotein ADH and aryl ADH genes, and four ALDH genes are probably involved in the conversion processes. 相似文献
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Hiroyuki Inoue Osamu Takimura Hiroyuki Fuse Katsuji Murakami Kazuo Kamimura Yukiho Yamaoka 《Applied microbiology》2000,66(8):3492-3498
Triphenyltin (TPT)-degrading bacteria were screened by a simple technique using a post-column high-performance liquid chromatography using 3,3′,4′,7-tetrahydroxyflavone as a post-column reagent for determination of TPT and its metabolite, diphenyltin (DPT). An isolated strain, strain CNR15, was identified as Pseudomonas chlororaphis on the basis of its morphological and biochemical features. The incubation of strain CNR15 in a medium containing glycerol, succinate, and 130 μM TPT resulted in the rapid degradation of TPT and the accumulation of approximately 40 μM DPT as the only metabolite after 48 h. The culture supernatants of strain CNR15, grown with or without TPT, exhibited a TPT degradation activity, whereas the resting cells were not capable of degrading TPT. TPT was stoichiometrically degraded to DPT by the solid-phase extract of the culture supernatant, and benzene was detected as another degradation product. We found that the TPT degradation was catalyzed by low-molecular-mass substances (approximately 1,000 Da) in the extract, termed the TPT-degrading factor. The other fluorescent pseudomonads, P. chlororaphis ATCC 9446, Pseudomonas fluorescens ATCC 13525, and Pseudomonas aeruginosa ATCC 15692, also showed TPT degradation activity similar to strain CNR15 in the solid-phase extracts of their culture supernatants. These results suggest that the extracellular low-molecular-mass substance that is universally produced by the fluorescent pseudomonad could function as a potent catalyst to cometabolite TPT in the environment. 相似文献
59.
Investigation of topical application of procyanidin B-2 from apple to identify its potential use as a hair growing agent. 总被引:1,自引:0,他引:1
Procyanidin B-2 is a polyphenol compound we have identified in apple which acts as a hair-growing factor in the murine model both in vitro and in vivo. This report describes our investigation of the effects of 1% procyanidin B-2 tonic on human hair growth after sequential use for 6 months. A double-blind clinical test involving a total of 29 subjects was performed. Nineteen men in the procyanidin B-2 group and 10 men in the placebo control group were subjected to analyses. No adverse side effects were observed in either group. The hair-growing effect was evaluated using a macrophotography technique combined with measurements of the hair diameter of clipped hairs. The increase in number of total hairs in the designated scalp area (0.5 cm square = 0.25 cm2 area) of procyanidin B-2 group subjects after the 6-month trial was significantly greater than that of the placebo control group subjects (procyanidin B-2, 6.68 +/- 5.53 (mean +/- SD)/0.25 cm2; placebo, 0.08 +/- 4.56 (mean +/- SD)/0.25 cm2; P < 0.005, two-sample t test). The increase in number of terminal hairs, which are defined as hairs more than 60 microm in diameter, in the designated area (0.5 cm square = 0.25 cm2 area) of the procyanidin B-2 group subjects after the 6-month trial was significantly greater than that of the placebo control group subjects (procyanidin B-2, 1.99 +/- 2.58 (mean +/- SD)/0.25 cm2; placebo, -0.82 +/- 3.40 (mean +/- SD)/0.25 cm2; P < 0.02, two-sample t test). Procyanidin B-2 therapy shows potential as a safe and promising cure for male pattern baldness. 相似文献
60.
The purpose of this study was to examine the effect of graded conditioning contractions of the antagonist knee flexor muscles on the output characteristics of knee extensor muscles in healthy humans. Eight male university students performed maximum isometric contractions of knee extensors, preceded by isometric conditioning contractions of the antagonist knee flexors. The developed force and electromyographic (EMG) amplitudes of the knee extensors after the conditioning contraction were measured and compared with those of simple knee extension without conditioning. The forces of the conditioning flexor contraction were set at three levels: low (20% of maximum voluntary contraction: MVC), moderate (60% of MVC), and high (100% of MVC). The EMG amplitudes of the vastus medialis, vastus lateralis, and rectus femoris muscle were recorded and the root mean square amplitudes were calculated. The strongest enhancement of the extension force was obtained by moderate intensity conditioning contraction (108.95+/-1.87% of simple knee extension), although high intensity conditioning also induced a significant increase (105.41+/-2.69%). Low intensity conditioning did not cause a significant enhancement of the contraction force (103.17+/-2.99%). Similarly, the EMG amplitudes were significantly increased by moderate and/or high conditioning. These results suggest that antagonist conditioning contraction of moderate intensities is sufficient and may be optimal to potentiate knee extensor contraction. 相似文献