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991.
992.
Observational studies suggest there are clinical benefits to moderate red wine (RW) consumption. However, the effects on coronary vasculature and overall lifestyle are unclear. We investigated whether a lifestyle of regular long-term RW consumption is associated with changes in coronary plaque burden, calcium score, carotid intima/media thickness, endothelial function, and metabolic variables, compared with alcohol abstinence. Healthy volunteers were evaluated by coronary computed tomography angiography (CTA) as well as carotid and brachial artery ultrasound. Nutritional status, psychological status, and metabolic variables were assessed. The study included 101 drinkers [aged 58.9±7.3 years (means±SD)], from wine brotherhoods, and 104 abstainers, from Anglican, Evangelical and Catholic churches both in the city of São Paulo, Brazil. No significant differences in demographics were noted. Lesion prevalence per patient assessed by coronary CTA and classified as absent (0), 1-25, 26-49, and ≥50% stenosis was similar between groups. When analyzed by individual arteries, i.e., left anterior descending, circumflex, and right coronary, prevalence was also not different. On the other hand, calcium scores were higher among drinkers than abstainers (144.4±362.2 vs 122.0±370.3; P<0.01). However, drinkers reported less history of diabetes and exercised more. RW drinkers consumed 2127.9±387.7 kcal/day while abstainers consumed 1836.0±305.0 (P<0.0001). HDL cholesterol was significantly higher among drinkers compared to abstainers (46.9±10.9 vs 39.5±9.0 mg/dL; P<0.001), while fasting plasma glucose was lower (97.6±18.2 vs 118.4±29.6 mg/dL; P<0.02). Liver enzymes were normal in both groups. In conclusion, long-term wine drinkers displayed a similar plaque burden but greater calcium score than abstainers, despite a more atherogenic diet, and the mechanisms for the increased calcium scores in the former remain speculative.  相似文献   
993.
Many adult survivors of repaired congenital heart disease (CHD) are at premature risk of death. Sudden cardiac arrest (SCA) is 1 of the leading causes of death but little is known about determinants for SCA in adults with repaired lesions. We sought to determine incidence and risk factors for SCA in a study population of 936 adults with previously repaired CHD who had completed follow-up at a single tertiary center during a mean period of 9 ± 7 years. Mean age at first examination in our institution was 21 ± 7 years. Diagnostic categories included tetralogy of Fallot (216), coarctation of the aorta (157), transposition complexes (99), single ventricle (55), and other CHD (409). During a total follow-up of 8,387 person-years, 22 patients (2.6 per 1,000 person-years) presented with SCA. Incidence of SCA varied widely between specific lesions; the highest incidence was observed in transposition complexes (10 per 1,000 person-years). Independent predictors of SCA were retrospectively identified using multivariate Cox proportional hazard modeling. Age at initial examination and severely impaired subaortic ventricular systolic function were independent risk factors for SCA (severe subaortic ventricular systolic dysfunction, adjusted hazard ratio 29, 95% confidence interval 11 to 72, p <0.001). SCA occurred in 23% of patients with severe subaortic ventricular systolic dysfunction versus 0.7% of patients with nonsevere decreased subaortic ventricular function (p <0.001). In conclusion, severe subaortic ventricular systolic dysfunction is a dominant multivariate predictor of SCA in an unselected population of adult survivors after surgery for CHD. Our data support the consideration of primary prevention strategies in these patients.  相似文献   
994.
995.
Little information is available on transplacental transmission of Leishmania spp. We determined the frequency and impact of congenital infection caused by Leishmania panamensis or L. donovani in experimentally infected hamsters. A polymerase chain reaction showed that congenital transmission occurred in 25.8% (24 of 93) of offspring born to L. panamensis-infected hamsters and 14.6% (11 of 75) offspring born to L. donovani-infected hamsters. Mortality during lactation was higher in offspring born to L. panamensis-infected hamsters and offspring born to L. donovani-infected hamsters than controls, and lymphoproliferation to Leishmania was more frequent in offspring born to L. panamensis-infected hamsters (17.4%, 11 of 63) than in offspring born to L. donovani-infected hamsters (8.5%, 3 of 35). After weaning, only offspring born to L. donovani-infected hamsters had lower weight gain (P < 0.001) and hematocrit levels (P = 0.0045) than controls. Challenge of offspring born to L. panamensis-infected hamsters with L. panamensis showed no differences in lesion evolution, and offspring born to L. donovani-infected hamsters were more susceptible to L. donovani challenge than controls. Consequently, prenatal exposure of hamsters to L. donovani significantly increased the mortality risk and susceptibility to secondary homologous infection.  相似文献   
996.
997.
The rhizobium-legume symbiosis has been widely studied as the model of mutualistic evolution and the essential component of sustainable agriculture. Extensive genetic and recent genomic studies have led to the hypothesis that many distinct strategies, regardless of rhizobial phylogeny, contributed to the varied rhizobium-legume symbiosis. We sequenced 26 genomes of Sinorhizobium and Bradyrhizobium nodulating soybean to test this hypothesis. The Bradyrhizobium core genome is disproportionally enriched in lipid and secondary metabolism, whereas several gene clusters known to be involved in osmoprotection and adaptation to alkaline pH are specific to the Sinorhizobium core genome. These features are consistent with biogeographic patterns of these bacteria. Surprisingly, no genes are specifically shared by these soybean microsymbionts compared with other legume microsymbionts. On the other hand, phyletic patterns of 561 known symbiosis genes of rhizobia reflected the species phylogeny of these soybean microsymbionts and other rhizobia. Similar analyses with 887 known functional genes or the whole pan genome of rhizobia revealed that only the phyletic distribution of functional genes was consistent with the species tree of rhizobia. Further evolutionary genetics revealed that recombination dominated the evolution of core genome. Taken together, our results suggested that faithfully vertical genes were rare compared with those with history of recombination including lateral gene transfer, although rhizobial adaptations to symbiotic interactions and other environmental conditions extensively recruited lineage-specific shell genes under direct or indirect control through the speciation process.  相似文献   
998.
999.
1000.
Epidemiological studies of Paget's disease of bone (PDB) have shown a remarkable geographical variation in the prevalence rates of the disease. In South America, the frequency is considered to be low, despite scant epidemiological data on this continent regarding the disease. The aim of this study was to evaluate the prevalence and incidence of PDB in one institution in the city of Recife, Northeast Brazil. All patients aged 45?years and over attending the Pernambuco Osteoporosis Centre at the Endocrine and Diabetes Department between January 2006 and December 2009 were assessed. Period prevalence and incidence density were calculated for each year for males and females separately, with confidence intervals and hypothesis test for difference between proportions. A total of 7,752 patients were assessed of which 53 presented with PDB. The total prevalence was 6.8 per 1,000 patients, and the incidence density for PDB was 50.3 per 10,000 person-years. Both prevalence and incidence increased during the period. Our data show that prevalence and incidence rates of PDB in Recife are comparable to those from Southern Europe. To our knowledge, this is the first epidemiological study of PDB in South America.  相似文献   
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