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51.
In a cross-sectional study of 2,802 perimenopausal caucasian women, carriage of at least one mutated allele of the 17-alpha-hydroxysteroid dehydrogenase type 1 (17-alpha HSD) vlV A-->C single nucleotide polymorphism (SNP) was associated with a significantly increased body mass index (mean 24.3 +/- 4.4 kg/m(2) vs. 23.5 +/- 4.2 kg/m(2); P<.001), and obesity was more frequent among mutant allele carriers (P=.06; odds ratio 1.38; 95% confidence interval 0.97-1.95), providing evidence of 17-alpha HSD as a candidate gene of perimenopausal obesity.  相似文献   
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In a prospective case-control study of 127 normozoospermic and 435 non-normozoospermic Caucasian men, the genotype frequencies of a polymorphism of the interleukin-1 beta gene (IL-1beta Taq C-->T) were statistically significantly different between groups (homozygous wild-type C/C [57%], heterozygous C/T [42%], and homozygous mutant T/T [1%] vs. C/C [57%], C/T [36%], T/T [7%] for normozoospermic and non-normozoospermic men, respectively; odds ratio, 4.8; 95% confidence interval, 1.13 to 20.28). This association was restricted to men with the oligoasthenoteratozoospermia (OAT) syndrome. We conclude that the investigated polymorphism is associated with sperm pathology in Caucasians.  相似文献   
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Sociodemographic factors including low maternal education, low economic status, inferior quality of housing, diminished access to water and sanitation facilities, and crowding in the household are associated with increased diarrhoea in the rural setting of many developing countries. To assess the relationship of these variables with diarrhoea rates in children in an urban setting we monitored the episodes of diarrhoea of children less than 6 years of age from 1921 families living in 51 clusters throughout Dhaka city, Bangladesh, for 3 1/2 months. Comparing incidence density ratios, we found that, of the factors listed above, only low family income and living in a one-room house were statistically associated with increased diarrhoea and that none of these variables was associated with a meaningfully increased risk of diarrhoea. We conclude that the risk factors for increased episodes of diarrhoea in the urban setting appear to be different from those of the rural setting.  相似文献   
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We examined the relationship between uses of the sari that are potential health hazards and episodes of diarrhoea in children younger than 6 years in 247 families living in 51 slums in Dhaka, Bangladesh. These misuses appeared to be common (median of three per observation period) and were largely unrecognized by the women as possible sources of disease transmission. There appeared to be a positive correlation between the number of misuses of the sari and episodes of childhood diarrhoea.  相似文献   
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MRP14 (S100A9) is the major calcium-binding protein of neutrophils and monocytes. Targeted gene disruption reveals an essential role of this S100 protein for transendothelial migration of phagocytes. The underlying molecular mechanism comprises major alterations of cytoskeletal metabolism. MRP14, in complex with its binding partner MRP8 (S100A8), promotes polymerization of microtubules. MRP14 is specifically phosphorylated by p38 mitogen-activated protein kinase (MAPK). This phosphorylation inhibits MRP8/MRP14-induced tubulin polymerization. Phosphorylation of MRP14 is antagonistically regulated by binding of MRP8 and calcium. The biologic relevance of these findings is confirmed by the fact that MAPK p38 fails to stimulate migration of MRP14(-/-) granulocytes in vitro and MRP14(-/-) mice show a diminished recruitment of granulocytes into the granulation tissue during wound healing in vivo. MRP14(-/-) granulocytes contain significantly less polymerized tubulin, which subsequently results in minor activation of Rac1 and Cdc42 after stimulation of p38 MAPK. Thus, the complex of MRP8/MRP14 is the first characterized molecular target integrating MAPK- and calcium-dependent signals during migration of phagocytes.  相似文献   
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Previous studies using the Hep G2-based VA cells showed that ethanol metabolism resulted in both cytotoxicity and impaired DNA synthesis, causing reduced accumulation of cells in culture. To further characterize the ethanol oxidation-mediated impairment of DNA synthesis we analyzed the cell-cycle progression of VA cells. These studies showed approximately a 6-fold increase in the percentage of cells in the G2/M phase of the cell cycle after 4 days of ethanol exposure. The G2/M transition requires activity of the cyclin-dependent kinase, Cdc2. Cdc2 is positively regulated by association with cyclin B1, and negatively regulated by phosphorylation of amino acids Thr14 and Tyr15. Immunoblot analysis revealed that ethanol metabolism had little affect on total Cdc2 content in these cells, but resulted in the accumulation of up to 20 times the amount of cyclin B1, indicating that cyclin B1 was available for formation of Cdc2/cyclin B1 complexes. Co-immunoprecipitation revealed that 6 times more Cdc2/cyclin B1 complexes were present in the ethanol-treated cells compared with the controls. Investigation of the phosphorylation state of Cdc2 revealed that ethanol oxidation increased the amount of the phosphorylated inactive form of Cdc2 by approximately 3-fold. Thus, the impairment in cell-cycle progression could not be explained by a lack of cyclin B1, or the ability of Cdc2 and cyclin B1 to associate, but instead resulted, at least in part, from impaired Cdc2 activity. In conclusion, ethanol oxidation by VA cells results in a G2/M cell-cycle arrest, mediated by accumulation of the phosphorylated inactive form of Cdc2.  相似文献   
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