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981.
982.
Tea has long been believed to be a healthy beverage, and its beneficial effects are almost all attributed to catechins. The effect of catechins on postprandial hypertriglyceridemia in rats was investigated in this study. A lipid emulsion administered orally to rats with (-)-epigallocatechin gallate at a dose of 100 mg/kg resulted in the increase in plasma triacylglycerol being significantly inhibited after 1 and 2 h compared to the case without (-)-epigallocatechin gallate. The effect of (-)-epigallocatechin was weaker than that of (-)-epigallocatechin gallate. A tea extract (THEA-FLAN 90S), mainly composed of catechins with a galloyl moiety, dose-dependently suppressed postprandial triacylglycerol after the administration of a lipid emulsion at doses of 50-200 mg/kg. The administration of the tea extract alone at a dose of 200 mg/kg had no effect on the plasma triacylglycerol level. These results strongly suggest that catechins with a galloyl moiety would be promising agents for suppressing dietary fat absorption through the small intestine.  相似文献   
983.
We investigated the optimum culture conditions for the production of a novel enzyme, N-substituted formamide deformylase, which acts mainly on N-benzylformamide, in Arthrobacter pascens F164. The highest enzyme activity was obtained when this strain F164 was cultivated in a synthetic medium with N-benzylformamide as sole nitrogen source. This deformylase was found to be an inducible enzyme depending on N-benzylformamide.  相似文献   
984.
The virulence of Yersinia enterocolitica is known to be highly dependent on its virulence plasmid. However, it remains unclear whether the virulence plasmid is engaged also in the induction of cell-mediated immunity that is essential for protective immunity in the host. In this study, we have compared the induction of type 1 helper T cell immunity against Y. enterocolitica using a virulent strain (P+) harboring the pYV plasmid and an avirulent strain (P-) harboring no pYV. Spleen cells from both groups of mice immunized with 1/10 LD50 of P+ strain and those with 1/10 LD50 of P- strain produced a high level of gamma interferon (IFN-gamma) upon stimulation with heat-killed bacteria, and CD4+ T cells were exclusively responsible for IFN-gamma production. When crude Yersinia outer proteins (Yops) were used for antigenic stimulation, IFN-gamma response of immune spleen cells against crude Yops was observed only in mice immunized with P+ strain. Flowcytometric analysis revealed a significant level of increase in IFN-gamma-producing CD8+ T cells as well as the increase in IFN-gamma-producing CD4+ T cells against crude Yops. These results suggest that the virulence plasmid of Y. enterocolitica is involved in the induction of Th1-type of possibly protective T cells in infected mice.  相似文献   
985.
Compound 7 was identified as the active metabolite of 6 by HPLC and mass spectral analysis. Modification of lead compound 7 by transformation of its N-oxide 6-6 biaryl ring system and fused aromatics produced a series of non-basic fXa inhibitors with excellent potency in anti-fXa and anticoagulant assays. The optimized compounds 73b and 75b showed sub to one digit micromolar anticoagulant activity (PTCT2). Particularly, anti-fXa activity was detected in plasma of rats orally administered with 1mg/kg of compound 75b.  相似文献   
986.
Adrenomedullin (AM) is postulated to exert organ-protective effects. It is expressed in the renal glomeruli, but its roles in the glomerular podocytes have been poorly elucidated. In the present study, we investigated the expression and regulation of AM in recently established conditionally immortalized mouse podocyte cell line in vitro and podocyte injury model in vivo. The cultured differentiated podocytes expressed AM mRNA and secreted measurable amount of AM. AM secretion from the podocytes was increased by H(2)O(2), hypoxia, puromycin aminonucleoside (PAN), albumin overload, and TNF-alpha. Real-time RT-PCR analysis revealed that AM mRNA expression in the podocytes was enhanced by PAN and TNF-alpha, both of which were suppressed by mitochondrial antioxidants. Furthermore, AM expression was upregulated in the glomerular podocytes of PAN nephrosis rats. These results indicated that AM expression in the podocytes was upregulated by stimuli or condition relevant to podocyte injury, suggesting its potential role in podocyte pathophysiology.  相似文献   
987.
988.
989.
In 3T3-L1 adipocytes, insulin or anisomycin stimulated phosphorylation of IRS-1 at Ser(307) and Ser(636/639), both of which were partially reduced by the mTOR inhibitor, rapamycin, or the JNK inhibitor, SP600125, and were further inhibited by a combination of them. Interestingly, anisomycin-induced p70(S6K) phosphorylation was reduced by SP600125, while insulin-induced p70(S6K) phosphorylation was not. Furthermore, unlike insulin, anisomycin failed to elicit translocation or degradation of IRS-1. These results indicate that mTOR and JNK play roles in phosphorylating IRS-1 serine residues, and that insulin and anisomycin are different in terms of the relationship of activation between mTOR and JNK, and the effects on IRS-1 localization and stability.  相似文献   
990.
The human MrgX3 gene, belonging to the mrgs/SNSRs (mas related genes/sensory neuron specific receptors) family, was overexpressed in transgenic rats using the actin promoter. Two animal lines showed cataracts with liquification/degeneration and swelling of the lens fiber cells. The transient epidermal desquamation was observed in line with higher gene expression. Histopathology of the transgenic rats showed acanthosis and focal parakeratosis. In the epidermis, there was an increase in cellular keratin 14, keratin 10, and loricrin, as well as PGP 9.5 in innervating nerve fibers. These phenotypes accompanied an increase in the number of proliferating cells. These results suggest that overexpression of the human MrgX3 gene causes a disturbance of the normal cell-differentiation process.  相似文献   
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