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551.
H Fujita  T Yamagami 《Life sciences》2001,70(2):219-227
A water-soluble Touchi-extract (TE) exerts a potent inhibitory activity against rat intestinal alpha-glucosidase in foodstuffs, and elicited anti-glycemic effects in rats and humans with single-bolus oral administration. In the present study, genetically modified diabetic model KKAy mice were used to examine the long-term effects of TE. Eight-week-old male KKAy mice were fed with CE-2 chow containing 0.08 and 0.4% of TE for 60 days. In the latter group, fasting blood glucose levels decreased (6.68 +/- 0.41 mmol/L) significantly (p<0.05) after a 60-day ingestion period compared with controls (8.75 +/- 0.54 mmol/L). Moreover, postprandial blood glucose levels were also significantly reduced (16.79 +/- 2.28 mmol/L; p<0.01) after ingesting TE for only 30 days compared with controls (28.49 +/- 0.59 mmol/L). On oral TE treatment for 60 days, postprandial increases in the blood glucose level after oral loading of sucrose (2 g/kg) at 30 (p<0.05) and 60 (p<0.01) min were significantly depressed compared with controls. Indexes for serum lipids; viz., total cholesterol (p<0.05) and triglyceride (p<0.01) levels significantly decreased after TE ingestion. Indexes for hepatic functions, such as glutamic-oxaloacetic transaminase (p<0.01), glutamic-pyruvic transaminase and gama-glutamyl transpeptide levels, were similarly suppressed. Organ weights of the heart, kidney, jejunum, liver and spleen increased in control KKAy mice due to hyperinsulinemia. Interestingly, the respective organ weights decreased (p<0.05, 0.01) and the jejunum length was reduced (p<0.05) significantly in the TE-treated groups. All in all, TE demonstrated an anti-hyperglycemic effect and may have potential use in the management of non-insulin-dependent diabetic mellitus.  相似文献   
552.
The pathogenesis of nonalcoholic steatohepatitis (NASH) is a two-stage process in which steatosis is the “first hit” and an unknown “second hit.” We hypothesized that “a binge” could be a “second hit” to develop NASH from obesity-induced simple steatosis. Thirty-week-old male Otsuka Long-Evans Tokushima fatty (OLETF) rats were administered 10 mL of 10% ethanol orally for 5, 3, 2, and 1 d/wk for 3 consecutive weeks. As control, male Otsuka Long-Evans Tokushima (OLET) rats were administered the same amount of alcohol. Various biochemical parameters of obesity, steatosis and NASH were monitored in serum and liver specimens in untreated and ethanol-treated rats. The liver sections were evaluated for histopathological alterations of NASH and stained for cytochrome P-4502E1 (CYP2E1) and 4-hydroxy-nonenal (4-HNE). Simple steatosis, hyperinsulinemia, hyperglycemia, insulin resistance, hypertriglycemia and marked increases in hepatic CYP2E1 and 4-HNE were present in 30-wk-old untreated OLETF rats. Massive steatohepatitis with hepatocyte ballooning was observed in the livers of all OLETF rats treated with ethanol. Serum and hepatic triglyceride levels as well as tumor necrosis factor (TNF)-α mRNA were markedly increased in all ethanol-treated OLETF rats. Staining for CYP2E1 and 4-NHE demonstrated marked increases in the hepatic tissue of all the groups of OLETF rats treated with ethanol compared with OLET rats. Our data demonstrated that “a binge” serves as a “second hit” for development of NASH from obesity-induced simple steatosis through aggravation of oxidative stress. The enhanced levels of CYP2E1 and increased oxidative stress in obesity play a significant role in this process.  相似文献   
553.
Abstract. Grid maps are used as a basic vegetation data base in Japan; they are simplified from vector-based vegetation maps. We estimated the frequency error or lack of information corresponding to reduced resolution and examined the reliable limits of this data base. We produced 10 grid maps on five different scales from 50 m to 1000 m using two different methods using both the whole cell (W-method) and only the central circle (C-method) from a vegetation map at scale 1: 25 000. We found that patches larger than the area of a cell on a vector-based map could be kept almost certainly on any map, but many patches of less than the cell size were lost. The number of missing patches with the C-method is fewer at every scale than those with the W-method. Though the value of Morisita's Cλ (p) index showed that the similarity with the original map was high - from the 50-m to the 200-m resolution - it was increasingly lower on the 400-m and 1000-m grid maps. The values of the Shannon index on the original map, 50-m and 100-m grid maps were not different, but they decreased from the 200-m to 1000-m grid maps. Because the vegetation data base of the Japanese Environment Agency used a 1000-m C-method grid map, we found that much information on patches less than 100 ha had disappeared. Information about dominant vegetation or large patches is almost accurate in this data base.  相似文献   
554.
Methionine enkephalin-like immunoreactivity (ME-LI) in the brain of El mice (seizure-susceptible strain) was measured by radioimmunoassay (RIA) to elucidate the relation between seizures and the opioid system. The lyophilized supernatants of tissue extracts were subjected to ME RIA. The concentration of ME-LI in 25-day-old El mice that had no seizures was significantly decreased in the hippocampus. At the age of 50 days when El mice displayed abortive seizures, the levels of ME-LI in both El(+) and nonstimulated El(o) mice were also significantly reduced in the hippocampus and septal area. It was further shown that the ME-LI concentrations in both 150-day-old adult El(+) during interictal periods and El(o) mice were markedly decreased in the cerebral cortex, septal area, and striatum, as compared with the corresponding regions in ddY mice (seizurenonsusceptible strain; the mother strain of El). The decrease of ME-LI in the El mouse brain was generally compatible with our previous findings concerning the up-regulation of opioid delta receptors in this species. These results suggest that the reduction of ME-LI in the El mouse brain is not due to convulsions, but could be associated with the pathogenesis of seizure diathesis and seizure manifestations in the El mouse.  相似文献   
555.

Background  

Duplicate genes are considered to have evolved through the partitioning of ancestral functions among duplicates (subfunctionalization) and/or the acquisition of novel functions from a beneficial mutation (neofunctionalization). Additionally, an increase in gene dosage resulting from duplication may also confer an advantageous effect, as has been suggested for histone, tRNA, and rRNA genes. Currently, there is little understanding of the effect of increased gene dosage on subcellular networks like signal transduction pathways. Addressing this issue may provide further insights into the evolution by gene duplication.  相似文献   
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