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91.
Effects of dietary soybean peptides on hepatic production of ketone bodies and secretion of triglyceride by perfused rat liver 总被引:2,自引:0,他引:2
Tamaru S Kurayama T Sakono M Fukuda N Nakamori T Furuta H Tanaka K Sugano M 《Bioscience, biotechnology, and biochemistry》2007,71(10):2451-2457
Soybean protein isolate (SPI) was digested with protease to produce a peptides containing the low-molecular fraction (LD3) or a mixture of high- and low-molecular fractions (HD1). Rats were fed a diets containing SPI, LD3, or HD1 at a protein level equivalent to the 20% casein diet for 4 weeks. The serum triglyceride concentration was lower in rats fed SPI, LD3, and HD1 diets than in rats fed the casein diet, and the differences were significant for the cholesterol-enriched diet. The value for the LD3 group was the lowest among all groups for both the cholesterol-free and -enriched diets. The level of triglyceride in the post-perfused liver was significantly lower in the LD3 and HD1 groups and the SPI group than in the casein group irrespective of the presence of cholesterol in the diet. In the cholesterol-free diet, LD3 feeding as compared to casein feeding caused a reduction in triglyceride secretion from the liver to perfusate and an increment of hepatic ketone body production. The addition of cholesterol to the diets somewhat attenuated these effects of LD3. These results suggest that the low-molecular fraction in soybean peptides causes triglyceride-lowering activity through a reduction in triglyceride secretion from the liver to the blood circulation and the stimulation of fatty acid oxidation in the liver. There is a possibility that soybean peptides modulate triglyceride metabolism by changes in the hepatic contribution. 相似文献
92.
Yamamoto M Kamata T DO ND Adachi Y Kinjo M Ando T 《Bioscience, biotechnology, and biochemistry》2007,71(11):2860-2863
Female moths of Lyclene dharma dharma (Arctiidae, Lithosiinae) produced three pheromone components (I-III), which strongly stimulated male antennae. Using GC-MS analysis and chemical derivatizations, the following structures were estimated: 6-methyl-2-octadecanone (I), 14-methyl-2-octadecanone (II), and 6,14-dimethyl-2-octadecanone (III). While the stereochemistry of the chiral centers could not be determined because it was difficult to collect a sufficient amount of the natural pheromone, the plain structures of I and II were confirmed by synthesis of the racemic mixtures starting from diols. These methyl-branched ketones have not been identified as a natural product, indicating that they constitute a new chemical group of lepidopteran female sex pheromones. 相似文献
93.
Miyazawa Atsuhiro Kanahara Nobuhisa Kogure Masanobu Otsuka Ikuo Okazaki Satoshi Watanabe Yoshinori Yamasaki Fumiaki Nakata Yusuke Oda Yasunori Hishimoto Akitoyo Iyo Masaomi 《Molecular biology reports》2022,49(3):2015-2024
Molecular Biology Reports - GABAergic system dysfunction has been implicated in the etiology of schizophrenia and of cognitive impairments in particular. Patients with treatment-resistant... 相似文献
94.
Onishi M Inoue M Araki T Iwabuchi H Sagara Y 《Bioscience, biotechnology, and biochemistry》2011,75(2):261-267
The potent odorants in the crust and crumb of white bread were identified and quantified by gas chromatography-mass spectrometry and gas chromatography/olfactometry. The weight loss ratio of the samples baked at 220 °C was controlled in the range of 0-28%. The odorants were classified into 5 types by the transfer characteristics: i) All amounts of odorant transferred from the crust to external space (type-I). ii) All transferred from the crust to the crumb and external space (type-II). iii) Certain amount remaining in the crust and the rest transferred to the crumb and external space (type-III). iv) All transferred from the crumb to external space (type-IV). v) Certain amount remaining in the crumb and the rest transferred to the crust and external space (type-V). The odorants of type-IV were not apparent after the crust had formed. The results indicate that the crust could be a barrier to prevent the odorants from being transferred to external space. 相似文献
95.
Antimalarial activity of endoperoxide compound 6-(1,2,6,7-tetraoxaspiro[7.11]nonadec-4-yl)hexan-1-ol
Sato A Hiramoto A Morita M Matsumoto M Komich Y Nakase Y Tanigawa N Hiraoka O Hiramoto K Hayatsu H Higaki K Kawai S Masuyama A Nojima M Wataya Y Kim HS 《Parasitology international》2011,60(3):270-273
Plasmodium falciparum, the major causative parasite for the disease, has acquired resistance to most of the antimalarial drugs used today, presenting an immediate need for new antimalarial drugs. Here, we report the in vitro and in vivo antimalarial activities of 6-(1,2,6,7-tetraoxaspiro[7.11]nonadec-4-yl)hexan-1-ol (N-251) against P. falciparum and Plasmodium berghei parasites. The N-251 showed high antimalarial potencies both in the in vitro and the in vivo tests (EC50 2.3 × 10−8 M; ED50 15 mg/kg (per oral)). The potencies were similar to that of artemisinin in vitro and greater than artemisinin's activity in vivo (p.o.). In addition, N-251 has little toxicity: a single oral administration at 2000 mg/kg to a rat gave no health problems to it. Administration of N-251 to mice bearing 1% of parasitemia (per oral 68 mg/kg, 3 times a day for 3 consecutive days) resulted in a dramatic decrease in the parasitemia: all the 5 mice given N-251 were cured without any recurrence, with no diarrhea or weight loss occurring in the 60 days of experiment. N-251 deserves more extensive clinical evaluation, desirably including future trials in the human. 相似文献
96.
Mammalian germ cells undergo global reprogramming of DNA methylation during their development. Global DNA demethylation occurs around the time when the primordial germ cells colonize the embryonic gonads and this coincides with dynamic changes in chromatin composition. Global de novo DNA methylation takes place with remarkably different dynamics between the two sexes, prospermatogonia attaining methylation during fetal stages and oocytes attaining methylation postnatally. Our hypothesis was that dynamic changes in chromatin composition may precede or accompany the wave of global DNA de novo methylation as well. We used immunocytochemistry to measure global DNA methylation and chromatin components in male and female mouse fetal germ cells compared to control somatic cells of the gonad. We found that global DNA methylation levels sharply increased in male germ cells at 17.5 days post coitum, but remained low in female germ cells at all fetal stages. Global changes in chromatin composition: i, preceded global DNA methylation in fetal germ cells; ii, sex specifically occurred in male but not in female germ cells; iii, affected active and repressive histone marks and iv, included histone tail and histone globular domain modifications. Our data suggest that dynamic changes of chromatin composition may provide a framework for the pattern of male-specific de novo DNA methylation in prospermatogonia. 相似文献
97.
98.
Culture and hybridization experiments on an ulva clade including the Qingdao strain blooming in the yellow sea 总被引:1,自引:0,他引:1
In the summer of 2008, immediately prior to the Beijing Olympics, a massive green tide of the genus Ulva covered the Qingdao coast of the Yellow Sea in China. Based on molecular analyses using the nuclear encoded rDNA internal transcribed spacer (ITS) region, the Qingdao strains dominating the green tide were reported to be included in a single phylogenetic clade, currently regarded as a single species. On the other hand, our detailed phylogenetic analyses of the clade, using a higher resolution DNA marker, suggested that two genetically separate entities could be included within the clade. However, speciation within the Ulva clade has not yet been examined. We examined the occurrence of an intricate speciation within the clade, including the Qingdao strains, via combined studies of culture, hybridization and phylogenetic analysis. The two entities separated by our phylogenetic analyses of the clade were simply distinguished as U. linza and U. prolifera morphologically by the absence or presence of branches in cultured thalli. The inclusion of sexual strains and several asexual strains were found in each taxon. Hybridizations among the sexual strains also supported the separation by a partial gamete incompatibility. The sexually reproducing Qingdao strains crossed with U. prolifera without any reproductive boundary, but a complete reproductive isolation to U. linza occurred by gamete incompatibility. The results demonstrate that the U. prolifera group includes two types of sexual strains distinguishable by crossing affinity to U. linza. Species identification within the Ulva clade requires high resolution DNA markers and/or hybridization experiments and is not possible by reliance on the ITS markers alone. 相似文献
99.
Seiza is a Japanese traditional floor sitting style, sitting down with both legs set at about a 180 degree angle and both femurs on both lower legs. We examined the influence of the somatic dysesthesia and decrease in voluntary toe flexion strength (VTF) induced by Seiza on the center of pressure (COP) sway. Fifteen adults participated in this experiment. COP Sway was measured immediately after a chair resting (pre-test), when a plantar dysethesia occurred (post-test A), and when a decrease (under 30% of maximal voluntary contraction (MVC)) in the VTF set in (post-test B). Tissue oxygenation kinetics in the soleus muscle and plantar somatosensory thresholds (ST) were measured just before each COP test and during Seiza. From starting Seiza, oxygenated hemoglobin/myoglobin decreased markedly and reached a plateau within about 6 min. ST abruptly increased at about 19 min from starting Seiza. VTF decreased to less than 30% MVC in 33% of the participants after 10 min from the acute increase in ST, and in 100% after 20 min. When sustaining Seiza for 19 min, ST rose and sway velocity and antero-posterior sway increased. With continued Seiza, VTF decreased to below 30% MVC at 10 - 20 min, and the above stated body sway further markedly increase. 相似文献
100.
Mevastatin induces apoptosis in HL60 cells dependently on decrease in phosphorylated ERK 总被引:1,自引:0,他引:1
Nishida S Matsuoka H Tsubaki M Tanimori Y Yanae M Fujii Y Iwaki M 《Molecular and cellular biochemistry》2005,269(1-2):109-114
Mevastatin which is an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme in cholesterol synthesis, suppress cell proliferation and induce apoptosis. However, the molecular mechanism of apoptosis induction is not well understood. So, in the present study, we attempted to clarify the mechanism by which mevastatin induces apoptosis in HL60 cells. It was found that mevastatin induced apoptosis. At that time, we observed an increase in caspase-3 activity and morphological fragmentation of the nuclei. The apoptosis induced by mevastatin was not inhibited by the addition of farnesyl pyrophosphate (FPP), squalene, ubiquinone, and isopentenyladenine, but was inhibited by the addition of geranylgeranyl pyrophosphate (GGPP). When we examined the survival signals at the time of apoptotic induction, we also observed that the administration of mevastatin had caused a remarkable decrease in the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2). However, other survival signals, such as nuclear factor kappa B (NF-kappaB), protein kinase B (Akt), and p38 mitogen-activated protein kinase (p38), exhibited no change. In addition, no quantitative change was observed in Bcl-2, which was an anti-apoptosis protein. It was also observed that apoptosis was induced when U0126, an MEK inhibitor, was added to the cells to inhibit ERK. These results suggested that mevastatin induced apoptosis when it inhibited GGPP biosynthesis and consequently decreased the level of phosphorylated ERK, which was a survival signal; moreover, at that time, there was no influence on NF-kappaB, Akt, p38, and Bcl-2. The results of this study also suggested that mevastatin could be used as an anticancer agent. 相似文献