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161.
The role of sexual dimorphic adipose tissue fat accumulation in the development of insulin resistance is well known. However, whether vitamin A status and/or its metabolic pathway display any sex- or depot (visceral/subcutaneous)-specific pattern and have a role in sexual dimorphic adipose tissue development and insulin resistance are not completely understood. Therefore, to assess this, 5 weeks old Wistar male and female rats of eight from each sex were provided either control or diabetogenic (high fat, high sucrose) diet for 26 weeks. At the end, consumption of diabetogenic diet increased the visceral fat depots (p < 0.001) in the males and subcutaneous depot (p < 0.05) in the female rats, compared to their sex-matched controls. On the other hand, it caused adipocyte hypertrophy (p < 0.05) of visceral depot (retroperitoneal) in the females and subcutaneous depot of the male rats. Although vitamin A levels displayed sex- and depot-specific increase due to the consumption of diabetogenic diet, the expression of most of its metabolic pathway genes in adipose depots remained unaltered. However, the mRNA levels of some of lipid droplet proteins (perilipins) and adipose tissue secretory proteins (interleukins, lipocalin-2) did display sexual dimorphism. Nonetheless, the long-term feeding of diabetogenic diet impaired the insulin sensitivity, thus affected glucose clearance rate and muscle glucose-uptake in both the sexes of rats. In conclusion, the chronic consumption of diabetogenic diet caused insulin resistance in the male and female rats, but did not corroborate with sexual dimorphic adipose tissue fat accumulation or its vitamin A status.  相似文献   
162.
Genetic selection and better control of the environment of the pigs have resulted in increased production levels concerning both reproduction and growth. Such high performances imply high physiological demands that may deteriorate health and welfare. The aims of this paper are to review the physiological challenges that pigs are facing, to identify possible consequences on health and welfare, to propose ways of detecting and correcting problems whenever possible. At weaning, piglets are submitted to abrupt changes in food supply, housing and social environment. Behavioural changes and efficient adaptations of the digestive tract are critical for their health and welfare. Physiological demands to support these adaptations and risks of failure are inversely related to the age of the pigs. During fattening, modern pigs have high daily weight gain especially of lean tissue as well as elevated feed conversion rate. These high growth performances are suspected to favour stress and disease susceptibility, undesirable behaviours as well as leg weakness, but further experimental data are necessary to validate these effects and find their origin. In reproductive females, high prolificacy generates elevated foetal demands for nutrients and space that are not fully met as shown by an increased number of light piglets having difficulties to adapt successfully to the neonatal life. During lactation, sows with high milk production have high nutrient requirements leading to intense catabolism that may affect their health, welfare and future reproductive abilities.  相似文献   
163.

Background

The occurrence of obstetric anal sphincter injuries (OASIS) - which may have serious, long-term effects on affected women, including faecal incontinence, despite primary repair - varies widely between countries and have been chosen one of the indicators for patient safety in Organisation for Economic Cooperation and Development (OECD) countries and in Nordic countries.

Findings

The aim of the study was to assess risks of OASIS among five university teaching hospitals and 14 non-university central hospitals with more than 1,000 deliveries annually during 1997-2007 in Finland. Women with singleton vaginal deliveries divided into two populations consisting of all 168,637 women from five university hospitals and all 255,660 women from non-university hospitals, respectively, derived from population-based register. Primiparous and multiparous women with OASIS (n = 2,448) were compared in terms of possible risk factors to primiparous and multiparous women without OASIS, respectively, using stepwise logistic regression analysis. The occurrences of OASIS varied from 0.7% to 2.1% in primiparous and from 0.1% to 0.3% in multiparous women among the university hospitals. Three-fold inter-hospital differences in OASIS rates did not significantly change after adjustment for patient mix or the use of interventions. In non-university hospitals OASIS rates varied from 0.2% to 1.4% in primiparous and from 0.02% to 0.4% in multiparous women, and the results remained virtually unchanged after adjustment for known risks.

Conclusions

Up to 3.2-fold inter-hospital differences in OASIS risk demonstrates significant differences in the quality of Finnish obstetric care.
  相似文献   
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166.
Personality traits are basic dimensions of behavioral variation, and twin, family, and adoption studies show that around 30% of the between‐individual variation is due to genetic variation. There is rapidly growing interest in understanding the evolutionary basis of this genetic variation. Several evolutionary mechanisms could explain how genetic variation is maintained in traits, and each of these makes predictions in terms of the relative contribution of rare and common genetic variants to personality variation, the magnitude of nonadditive genetic influences, and whether personality is affected by inbreeding. Using genome‐wide single nucleotide polymorphism (SNP) data from > 8000 individuals, we estimated that little variation in the Cloninger personality dimensions (7.2% on average) is due to the combined effect of common, additive genetic variants across the genome, suggesting that most heritable variation in personality is due to rare variant effects and/or a combination of dominance and epistasis. Furthermore, higher levels of inbreeding were associated with less socially desirable personality trait levels in three of the four personality dimensions. These findings are consistent with genetic variation in personality traits having been maintained by mutation–selection balance.  相似文献   
167.

Background  

The fatty acids of anaerobic ammonium oxidizing (anammox) bacteria contain linearly concatenated cyclobutane moieties, so far unique to biology. These moieties are under high ring strain and are synthesised by a presently unknown biosynthetic pathway.  相似文献   
168.
Glycosylation of proteins and lipids is important in cellular communication and maintenance of tissues. B3GTL (beta3-glycosyltransferase-like) is a novel glycosyltransferase that is found in multicellular animals ranging from mammals to insects and nematodes. The aim of this work was to identify and characterize the B3GTL gene in the mouse and to study its expression in various tissues. The murine gene codes for a protein which shares 84% amino acid sequence identity with its human ortholog, and contains all the primary structural features that characterize B3GTL proteins. The murine and human B3GTL genes share an identical exon/intron organization, and both genes utilize multiple polyadenylation signals. Their promoter regions show extensive conservation, implying that the two genes also share regulatory similarities. This notion was reinforced by Northern hybridization analysis of mouse tissues, which showed the tissue distribution of B3GTL mRNA to be similar to that previously found in human tissues, with the heart, kidney, and brain being major sites of expression in both species. The localization of B3GTL mRNA was studied by in situ hybridization in an extensive collection of mouse tissues, of which the granular cells of the olfactory bulb and the epithelium of the seminal vesicle displayed particularly strong signals. Together, these analyses indicate that the B3GTL mRNA is subject to strong tissue-specific and developmental regulation. The findings reported here make possible the design of a B3GTL "knock-out" mouse, provide a framework for analyzing the regulation of the gene, and provide an extensive catalog of tissues in which this novel protein acts.  相似文献   
169.
Adiponectin gene haplotype is associated with preeclampsia   总被引:2,自引:0,他引:2  
We determined whether the polymorphism of the gene encoding adiponectin contributes to susceptibility to preeclampsia. The study involved 133 Finnish women with preeclampsia and 245 healthy control subjects. All women were genotyped for two single nucleotide polymorphisms (SNPs), SNP45 in exon 2 and SNP276 in intron 2, in the adiponectin gene. Chi2 analysis was used to assess genotype and allele frequency differences between the preeclamptic and control groups. In addition, the pair of loci haplotype analysis, using the expectation-maximization (EM) algorithm, was used to examine the estimated haplotype frequencies of the two SNPs, among the two groups. The TT genotype versus the pooled G genotypes in SNP276 was associated with protection against preeclampsia (p = 0.012) at an odds ratio of 0.27 (95% confidence interval [CI]: 0.09-0.80). Also the genotype and allele frequency distributions of SNP276 differed significantly between the preeclampsia group and the control group (p = 0.035 and p = 0.043, respectively). Single-point genotype and allele distributions in SNP45 of the adiponectin gene were not statistically different between the groups. In the haplotype estimation analysis, the pooled G haplotypes versus the TT haplotype were significantly overrepresented in the preeclampsia group (p = 0.042 +/- 0.005). Polymorphisms of the adiponectin gene show a weak, but statistically significant, haplotype association with susceptibility to preeclampsia in Finnish women.  相似文献   
170.
Peatland buffer zones with sedimentation ponds are established with the intention of capturing solids and nutrients liberated in drained forestry catchments. As noted in earlier fertilization experiments, added nitrogen (N) immediately increases nitrous oxide (N2O) emissions in such buffers, and we expected the same to happen after disturbances in the catchment caused by clear-cutting, soil preparation, and ditch cleaning. We measured N2O fluxes, water table dynamics, and vegetation cover from a wetland one year before and two years after the clear-cut and buffer establishment. The low pre-harvest emissions did not increase, but N2O emissions from the sedimentation pond exceeded those from humic lakes with a high N load. In the soil profile, N2O concentrations were high, indicating a potential to produce N2O in the buffer. In one sub-site the soil N2O concentration was below the atmospheric level, which was in accordance with the high concentrations of carbon dioxide (CO2) and methane (CH4). The change in vegetation along the overland flow paths could be explained by a shift in the species thriving in wet conditions but not in those requiring higher nutrient levels. In spite of the apparent potential of soil to produce N2O, the fluxes to the atmosphere remained low. Transformation of N2O to unobserved N2 may explain some of the low N emissions, together with the low concentrations entering the buffer.  相似文献   
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