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141.
Mitsuru Ando Masayuki Nakagawa Toshiie Nakamura Kazuo Tomita 《Bioscience, biotechnology, and biochemistry》2013,77(4):803-809
Excretion, distribution and metabolism of the insecticide, Isoxathion, administered orally in male Wistar-strain rats, were investigated with a carbon-14 labeled chemical. During 96 hr, approximately 85% and 14% of the total radioactivity were excreted in the urine and feces. Distribution of isoxathion after oral administration in the rats was investigated by means of whole-body autoradiographic technique and measurement of radioactivity in the tissues. At least eleven radioactive metabolites were detected, four of which were structurally determined. They were 3-hydroxy-5-phenylisoxazole, 3-(β-d-glucopyranuronosyloxy)-5-phenylisoxazole, 5-phenyl-3-isoxazolyl sulfate and hippuric acid. 相似文献
142.
We reported previously that an ndhB gene disruptant, ΔndhB, had the same phenotype as wild-type tobacco plants under normal growth conditions. Two other groups have reported conflicting phenotypes with each other for ndhCKJ operon disruptants. Here, we generated two transformants in which the ndhCKJ operon was disrupted, and found that new transformants had the same phenotype as ΔndhB. After illumination with visible light, all ndh disruptants had higher levels of steady-state fluorescence than wild-type controls when measured under weak light, suggesting that reduction of the plastoquinone pool in ndh disruptants was greater than that in wild-type controls. The weak light itself could not reduce the plastoquinone much, so the reduction in the plastoquinone in the mutant was due to electron donation from stromal reductants generated during illumination with the strong light. These results supported the hypothesis that NAD(P)H dehydrogenase prevents overreduction in chloroplasts and suggested that chlororespiratory oxidase did not function under low light or in the dark. 相似文献
143.
Masayoshi Tabata Takahiro Kido Masayuki Totani Takashi Murachi 《Bioscience, biotechnology, and biochemistry》2013,77(7):1909-1910
(22R,23R,24S)-3α,5-Cyclo-22,23-diacetoxy-5a-ergostan-6-one (2b) is a new key intermediate of some naturally occurring brassinosteroids such as brassinolide (la), castasterone (lb), teasterone (lc) and typhasterol (Id). The cycloketone 2b was prepared in 10 steps via (22R,23R,24S)-6p- benzyloxy-3a,5-cyclo-22,23-dihydroxy-5a-ergostane (5) from stigmasterol. 2b was treated with a catalytic amount of /7-toluenesulfonic acid and sodium bromide to give an enone (7b), which was oxidized with osmium tetroxide and derived to give a 2a,3a-acetonide (8b). 8b was easily separated from its isomer by the use of silica gel column chromatography. 8b was oxidized with tri- fluoroperacetic acid and deacetylated to give la. 8b was deacetylated and deacetonized to give lb. 2b was treated with dilute sulfuric acid in acetic acid to give a 3/^-acetate (10). 10 was treated with sodium hydroxide to give lc. 2b was treated with hydrobromic acid to give a 3/i-bromide (12), which was treated with silver acetate to give a 3a-acetate (13). 13 was treated with sodium hydroxide to give Id. 相似文献
144.
Mitsuru Ando Toshiie Nakamura Masayuki Nakagawa 《Bioscience, biotechnology, and biochemistry》2013,77(12):2451-2456
Excretion, distribution and metabolism of the fungicide, hymexazol, (3-hydroxy-5-methylisoxazole), labeled with carbon-14 were examined after administration of a single oral dose to Wistar-strain rats. Hymexazol was rapidly absorbed and distributed in the tissues. During 96 hr, 97% of the total radioactivity was excreted in the urine and 0.89% in the feces, and 0.86% was found in the expired gasses for 24 hr. Two metabolites were detected in the urine, whose chemical structures were determined as 3-(β-d-glucopyranuronosyloxy)-5- methylisoxazole and 5-methyl-3-isoxazolyl sulfate. 相似文献
145.
Masayuki Nakagawa Toshiie Nakamura Kazuo Tomita 《Bioscience, biotechnology, and biochemistry》2013,77(11):2205-2208
Photolysis of 3-hydroxy-5-phenylisoxazole in methanol with a low-pressure mercury lamp afforded 5-phenyl-4-oxazolin-2-one, together with small amounts of benzoic acid and benzoylacetamide. Similarly, 3-hydroxy-5-methylisoxazole in distilled water afforded 5-methyl-4-oxazolin-2-one as the major product. Both isoxazoles were stable in sunlight for up to 20 days. 相似文献
146.
Kohei Oda Takanori Imanishi Yoshito Yamane Yoshie Ueno Yoshiharu Mori 《Bioscience, biotechnology, and biochemistry》2013,77(5):882-890
Addition of γ-aminobutyric acid (GABA) and angiotensin converting enzyme (ACE)-inhibitory peptides to the pickles was studied in order to develop a new type of pickles that reduce blood pressure. Based on the outcome of these studies, a new type of fermentation bed composed of rice bran and white miso has been successfully developed. The advantage of such pickles is that they not only contain both GABA and ACE-inhibitory peptides, but also that their taste and flavor are excellent, with colors close to the original ones. The new type of pickles could temporarily reduce blood pressure in two types of rats, spontaneously hypertensive rats and NaCl-sensitive model rats. Thus, the newly developed pickles appear to be beneficial for pickle business. 相似文献
147.
Youji Nakagawa Toru Hasebe Miyuki Ishiai Hideki Yamamura Yuzuru Iimura Masayuki Hayakawa 《Bioscience, biotechnology, and biochemistry》2013,77(4):714-717
We constructed a plasmid that expresses FLO11 encoding a cell surface glycoprotein of Saccharomyces cerevisiae under the control of a constitutive promoter. This plasmid conferred pellicle-forming ability on the non-pellicle-forming industrial strain of S. cerevisiae at the air–liquid interface of the glucose-containing liquid medium. The induced pellicle-forming cells exhibited tolerance to furfural, which is a key toxin in lignocellulosic hydrolysates, in ethanol production. 相似文献
148.
Vimbai Samukange Masayuki Kamo Kiyoshi Yasukawa 《Bioscience, biotechnology, and biochemistry》2013,77(9):1522-1528
Neutral salts activate and stabilize thermolysin. In this study, to explore the mechanism, we analyzed the interaction of 8-anilinonaphthalene 1-sulphonate (ANS) and thermolysin by ANS fluorescence. At pH 7.5, the fluorescence of ANS increased and blue-shifted with increasing concentrations (0–2.0?μM) of thermolysin, indicating that the anilinonaphthalene group of ANS binds with thermolysin through hydrophobic interaction. ANS did not alter thermolysin activity. The dissociation constants (Kd) of the complex between ANS and thermolysin was 33?±?2?μM at 0?M NaCl at pH 7.5, decreased with increasing NaCl concentrations, and reached 9?±?3?μM at 4?M NaCl. The Kd values were not varied (31?34?μM) in a pH range of 5.5?8.5. This suggests that at high NaCl concentrations, Na+ and/or Cl– ions bind with thermolysin and affect the binding of ANS with thermolysin. Our results also suggest that the activation and stabilization of thermolysin by NaCl are partially brought about by the binding of Na+ and/or Cl– ions with thermolysin. 相似文献
149.
Megumi?IdaEmail author Itsurou?Ida Naoki?Wada Makoto?Sohmiya Masayuki?Tazawa Kenji?Shirakura 《BioPsychoSocial medicine》2013,7(1):18
Background
The efficacy of physical exercise as an augmentation to pharmacotherapy with antidepressants for depressive patients has been documented. However, to clarify the effectiveness of exercise in the treatment of depression, it is necessary to distinguish the effect of the exercise itself from the effect of group dynamics. Furthermore, an objective measurement for estimation of the effect is needed. Previous reports adopted a series of group exercises as the exercise intervention and mainly psychometric instruments for the measurement of effectiveness. Therefore, this clinical study was done to examine the effectiveness of a single session of individual exercise on depressive symptoms by assessing the change in saliva free cortisol level, which reflects hypothalamic-pituitary-adrenocortical axis function that is disturbed in depressive patients.Method
Eighteen medicated patients, who met the DSM-IV-TR criteria for major depressive disorder, were examined for the change in saliva free cortisol levels and the change in subjective depressive symptoms before and after pedaling a bicycle ergometer for fifteen minutes. Within a month after the exercise session, participants conducted a non-exercise control session, which was sitting quietly at the same time of day as the exercise session.Results
Depressed patients who participated in this study were in remission or in mild depressive state. However, they suffered chronic depression and had disturbed quality of life. The saliva free cortisol level and subjective depressive symptoms significantly decreased after the exercise session. Moreover, the changes in these variables were significantly, positively correlated. On the other hand, although the subjective depressive symptoms improved in the control session, the saliva free cortisol level did not change.Conclusion
For the first time in depressive patients, we were able to show a decrease in the saliva free cortisol level due to physical exercise, accompanied by the improvement of subjective depressive symptoms. This identified a possible influence of exercise on the hypothalamic-pituitary-adrenal axis in depression.These results suggest the utility of assessing the effect of physical exercise by saliva free cortisol level in depressive patients who suffer from bio-psycho-social disability.150.
Yoshiyasu Fujimura Masayuki Takada Hiroko Fujita Takashi Inoue 《Landscape and Ecological Engineering》2013,9(2):305-309
In recent decades, the extent of Sasa palmata-dominant communities has increased in Sarobetsu Mire in northern Hokkaido, Japan, replacing the original Sphagnum bog vegetation. However, this marked increase in distribution of Sasa in the mire has not been formally documented or investigated in detail. Using aerial photo-interpretation, the present study updated the distribution maps of Sasa communities, showing the changes that have occurred to these communities between 1977 and 2003. The results revealed that the extent of Sasa communities has increased by 15.8 % from 6.60 km2 in 1977 to 7.64 km2 in 2003. The most marked increase occurred on the ground associated with drainage channels, although the oldest channels were constructed more than half a century ago, suggesting that some responses to the drainage of peat bog ecosystems may take a considerable period of time before becoming particularly evident. 相似文献