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1.
The ability of human uterine endometrium to aromatize androstenedione to estrogens was investigated using 10 normal and neoplastic tissues. Normal and neoplastic endometrial homogenates were incubated with [6,7-3H]androstenedione (A) and NADPH. Estrone (E1) and estradiol (E2) were subsequently isolated in amounts ranging from 0-17600 fmol/h/g and 0-377 fmol/h/g, respectively, from the incubates after purifications by using Bio-Rad AG1-X2 column, thin layer chromatographies and co-crystallization. The conversion of A to E1 and E2 was significantly higher in neoplastic tissues. 相似文献
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Import and processing of the precursor of cytochrome P-450(SCC) by bovine adrenal cortex mitochondria 总被引:3,自引:0,他引:3
Isolated bovine adrenal cortex mitochondria imported in vitro synthesized pre-P-450(SCC) and processed it to the mature form. Partial radio-sequencing of the processed P-450(SCC) gave a result identical with that for authentic P-450(SCC). Rat liver mitochondria also imported pre-P-450(SCC) and processed it to the mature form, whereas bovine heart mitochondria were unable to import and process pre-P-450(SCC) although both mitochondrial preparations imported and processed pre-adrenodoxin. The pre-P-450(SCC) processing activity of bovine adrenal cortex mitochondria was associated with the matrix side surface of the inner membrane. The processing protease could be solubilized by sodium cholate and partially purified by ammonium sulfate fractionation. The partially purified processing protease cleaved pre-P-450(SCC) at the correct position. It was also active in processing pre-P-450(11 beta) but inactive toward pre-adrenodoxin. Bovine heart mitochondria lacked the processing activity to pre-P-450(SCC). The localization of pre-P-450(SCC) and mature P-450(SCC) in bovine adrenal cortex mitochondria was examined. Mature P-450(SCC) processed by the mitochondria was found associated with the matrix-side surface of the inner membrane, which is the correct location of P-450(SCC) in the cell. In the presence of o-phenanthroline, pre-P-450(SCC) was imported into the organelles without being processed and remained soluble in the matrix. The incorporation of newly processed mature P-450(SCC) into the inner membrane was also observed when pre-P-450(SCC) was incubated with inner membrane vesicles. Mature P-450(SCC) generated in vitro from pre-P-450(SCC) by the partially purified processing protease was incorporated not only into the inner membrane vesicles but also into bovine adrenal cortex microsomes. These findings suggested that the processing of pre-P-450(SCC) occurred prior to the incorporation of mature-P-450(SCC) into the inner membrane. 相似文献
3.
Shigeo Koyasu Makoto Asada Akio Fukuda Yoshimi Okada 《Journal of molecular biology》1981,153(2):471-475
The mode of polymerization of two species of flagellins, flagellin A and flagellin B, in polar flagella of Caulobacter crescentus was examined. By immunological staining we found that 1 to 1.2 μm of the portion of the flagellar filament proximal to the cell was composed of flagellin B, whereas about 5 μm of the distal portion was composed of flagellin A. This result, together with the previous observation that a flagellin B-less mutant cannot form normal flagella but instead forms stubs in spite of their high level of flagellin A synthesis, indicates that flagellin B is very important for the formation of complete flagella and/or for the initiation of filament formation from the hook. 相似文献
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Synthesis of cytochrome c oxidase in the liver of Rana catesbeiana tadpole treated with griseofulvin
The effect of griseofulvin treatment on the synthesis of cytochrome c oxidase was studied with the liver of the tadpole, Rana catesbeiana. (1) In the liver of tadpole treated with griseofulvin, a ferrochelatase inhibitor, the synthesis of heme a, but not cytochrome c oxidase protein, is inhibited. (2) The apocytochrome c oxidase which is formed in the liver of tadpole treated with griseofulvin is converted to the active holoenzyme by exogenously added heme a. 相似文献
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Yuichi Esaki Kenji Obayashi Keigo Saeki Kiyoshi Fujita Nakao Iwata Tsuyoshi Kitajima 《Chronobiology international》2020,37(6):887-896
ABSTRACT Previous studies have found that keeping the room dark at night was associated with a decrease in manic symptoms for patients with bipolar disorder (BD). However, the association between light at night of real-life conditions and manic symptoms is unclear. We investigated the association between bedroom light exposure at night and manic symptoms in BD patients. One-hundred and eighty-four outpatients with BD participated in this cross-sectional study. The average light intensity at night during sleep was evaluated using a portable photometer for seven consecutive nights. Manic symptoms were assessed using the Young Mania Rating Scale (YMRS), and scores ≥5 were treated as a “hypomanic state.” The median (interquartile range) YMRS score was 2.0 (0–5.0), and 52 (28.2%) participants were in a hypomanic state. The prevalence of a hypomanic state was significantly higher in the participants with an average light intensity at night exposure of ≥3 lux than in those with <3 lux (36.7% versus 21.9%; P = .02). In multivariable logistic regression analysis adjusted for BD type, depressive symptoms, sleep duration, and daytime physical activity, the odds ratio (OR) for a hypomanic state was significantly higher for the participants with an average light intensity at night exposure of ≥3 lux than for those with <3 lux (OR: 2.15, 95% confidence interval: 1.09–4.22, P = .02). This association remained significant at the cutoff value of YMRS score ≥6 (OR: 2.51, 95% confidence interval: 1.15–5.46; P = .02). The findings of this study indicate bedroom light exposure at night is significantly associated with manic symptoms in BD patients. Although the results of this cross-sectional investigation do not necessarily imply causality, they may serve to inform beneficial nonpharmacological intervention and personalized treatment of BD patients. 相似文献