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131.
Yoichi Ozawa Kenji Mori Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(7):1383-1386
Thirty eight new compounds with juvenile hormone (JH) activity were synthesized and evaluated biologically on Bombyx mori L. Among them, the activities of 7,8-epoxy-4,8-dimethyl-1 -(p-ethylphenoxy)-3-undecene and 7,8-epoxy-4,8-dimethyl-l-(p-methylphenoxy)-3-undencene were proved to be more than two thousand times as high as that of the C18-Cecropia JH (mixed isomers). Structure-activity relationship of these compounds was discussed. 相似文献
132.
Masanao Matsui Kenji Mori Yoichi Ozawa 《Bioscience, biotechnology, and biochemistry》2013,77(2):193-195
A synthesis of oospolactone (3,4-dimethyl-8-hydroxyisocoumarin), a metabolite of Oospora astringenes, is described. 相似文献
133.
Yoshiaki Iwamuro Michiko Murata Koichiro Kanamaru Yoichi Mikami Takuro Kisaki 《Bioscience, biotechnology, and biochemistry》2013,77(2):525-526
The aroL gene, encoding shikimate kinase of Brevibacterium lactofermentum, a coryneform glutamic acid-producing bacterium, was cloned. Recombinant plasmids containing the aroL gene caused elevated levels of shikimate kinase synthesis in B. lactofermentum. It was found that in addition to the aroL gene, the aroB and aroE genes, encoding dehydroquinate synthase and shikimate dehydrogenase, respectively, also existed on these recombinant plasmids, in complementation tests with various Escherichia coli and B. lactofermentum aromatic amino acid auxotrophs. The aroL, aroB and aroE genes of B. lactofermentum are located closely on the cloned DNA fragment, in that order. It was shown that at least these three aro genes form a cluster on the chromosome of B. lactofermentum. 相似文献
134.
Kazunori Sasaki Tomoyuki Oki Yumi Kai Yoichi Nishiba 《Bioscience, biotechnology, and biochemistry》2013,77(8):1308-1314
The purpose of this study was to investigate the effect of repeated harvesting on the content of caffeic acid (CA) and seven species of caffeoylquinic acids (CQAs) in sweet potato leaves using a newly developed high-performance liquid chromatography method. Six cultivars and two breeding lines were used in this study. Leaves were collected at monthly intervals from 1st harvest (May) to 4th harvest (August) in 2011 and 2012. ANOVA analysis revealed that the contents of CQAs were significantly different among all cultivars and breeding lines, but no significant differences were found for CA. No annual variation was confirmed in CA and CQAs. Repeated harvest of sweet potato leaves affected the content of only 4-CQA and 5-CQA. Post-hoc comparisons using Tukey’s method indicated that the contents of 4-CQA and 5-CQA in sweet potato leaves harvested at first time were significantly higher compared to those at the other harvest times. 相似文献
135.
Yoichi Ozawa Kenji Mori Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(10):2373-2378
Sixteen new Cecropia juvenile hormone (JH) analogs with different alkyl substituents at C–7 and C–11 were synthesized as stereoisomeric mixtures. The epoxides with n-propyl or n-butyl and methyl groups at C-11 and methyl or ethyl group at C-7 showed high JH activity on Bombyx mori L. Structure-activity relationship of the JH analogs was discussed. 相似文献
136.
Yoshio Nakao Tsuneo Kanamaru Masakazu Kikuchi Saburo Yamatodani 《Bioscience, biotechnology, and biochemistry》2013,77(10):2399-2404
The addition of penicillin to cells of Corynebacterium alkanolyticum No. 314 growing on n-paraffins medium caused the simultaneous excretion of phospholipids, UDP-N-acetylhexosamine derivatives and L-glutamic acid.Among many antibiotics which inhibit cell wall synthesis, only the inhibitors of peptideglycan transpeptidase such as penicillin G and cephaloridine were effective for inducing the excretion of phospholipids, UDP-N-acetylhexosamine derivatives and L-glutamic acid, while the others promoted only the excretion of UDP-N-acetylhexosamine derivatives.From the close relationship between the excretion of L-glutamic acid and the excretion of phospholipids, it was suggested that the action of penicillins and cephalosporins on the cell membrane resulted in the excretion of L-glutamic acid. 相似文献
137.
Masaru Suzuki Mitsuzo Kuno Yoshio Nakao 《Bioscience, biotechnology, and biochemistry》2013,77(2):365-371
In order to elucidate the biochemical mechanism of the alkaline protease accumulation from n-paraffins by a kabicidin-resistant mutant of Fusarium sp., the cell constituents and the extracellular products of the mutant strain were compared with those of the parent strain. No prominent differences in the cell constituents were observed between the parent and the mutant. From the analysis of the extracellular products, however the mutant was found to have a high productivity of some hydrolytic enzymes, such as amylase and ribonuclease, and ergosterol which is a structural constituent of fungal cell membrane. The relationship of secretion of ergosterol, resistance to kabicidin and accumulation of alkaline protease is discussed. 相似文献
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140.
Natural killer (NK) cell malignancies, particularly aggressive NK cell leukaemias and lymphomas, have poor prognoses. Although recent regimens with L-asparaginase substantially improved outcomes, novel therapeutic approaches are still needed to enhance clinical response. Resveratrol, a naturally occurring polyphenol, has been extensively studied for its anti-inflammatory, cardioprotective and anti-cancer activities. In this study, we investigated the potential anti-tumour activities of resveratrol against the NK cell lines KHYG-1, NKL, NK-92 and NK-YS. Resveratrol induced robust G0/G1 cell cycle arrest, significantly suppressed cell proliferation and induced apoptosis in a dose- and time-dependent manner for all four cell lines. In addition, resveratrol suppressed constitutively active STAT3 in all the cell lines and inhibited JAK2 phosphorylation but had no effect on other upstream mediators of STAT3 activation, such as PTEN, TYK2, and JAK1. Resveratrol also induced downregulation of the anti-apoptotic proteins MCL1 and survivin, two downstream effectors of the STAT3 pathway. Finally, resveratrol induced synergistic effect on the apoptotic and antiproliferative activities of L-asparaginase against KHYG-1, NKL and NK-92 cells. These results suggest that resveratrol may have therapeutic potential against NK cell malignancies. Furthermore, our finding that resveratrol is a bonafide JAK2 inhibitor extends its potential benefits to other diseases with dysregulated JAK2 signaling. 相似文献