Environmental factors influence both abundance and genetic diversity in a widespread bird species.

Genetic diversity is one of the key evolutionary variables that correlate with population size, being of critical importance for population viability and the persistence of species. Genetic diversity can also have important ecological consequences within populations, and in turn, ecological factors may drive patterns of genetic diversity. However, the relationship between the genetic diversity of a population and how this interacts with ecological processes has so far only been investigated in a few studies. Here, we investigate the link between ecological factors, local population size, and allelic diversity, using a field study of a common bird species, the house sparrow (Passer domesticus). We studied sparrows outside the breeding season in a confined small valley dominated by dispersed farms and small-scale agriculture in southern France. Population surveys at 36 locations revealed that sparrows were more abundant in locations with high food availability. We then captured and genotyped 891 house sparrows at 10 microsatellite loci from a subset of these locations (N = 12). Population genetic analyses revealed weak genetic structure, where each locality represented a distinct substructure within the study area. We found that food availability was the main factor among others tested to influence the genetic structure between locations. These results suggest that ecological factors can have strong impacts on both population size per se and intrapopulation genetic variation even at a small scale. On a more general level, our data indicate that a patchy environment and low dispersal rate can result in fine-scale patterns of genetic diversity. Given the importance of genetic diversity for population viability, combining ecological and genetic data can help to identify factors limiting population size and determine the conservation potential of populations

Novel associations of UDP-glucuronosyltransferase 2B gene variants with prostate cancer risk in a multiethnic study.

BACKGROUND: We have previously shown that a functional polymorphism of the UGT2B15 gene (rs1902023) was associated with increased risk of prostate cancer (PC). Novel functional polymorphisms of the UGT2B17 and UGT2B15 genes have been recently characterized by in vitro assays but have not been evaluated in epidemiologic studies. METHODS: Fifteen functional SNPs of the UGT2B17 and UGT2B15 genes, including cis-acting UGT2B gene SNPs, were genotyped in African American and Caucasian men (233 PC cases and 342 controls). Regression models were used to analyze the association between SNPs and PC risk. RESULTS: After adjusting for race, age and BMI, we found that six UGT2B15 SNPs (rs4148269, rs3100, rs9994887, rs13112099, rs7686914 and rs7696472) were associated with an increased risk of PC in log-additive models (p < 0.05). A SNP cis-acting on UGT2B17 and UGT2B15 expression (rs17147338) was also associated with increased risk of prostate cancer (OR = 1.65, 95% CI = 1.00-2.70); while a stronger association among men with high Gleason sum was observed for SNPs rs4148269 and rs3100. CONCLUSIONS: Although small sample size limits inference, we report novel associations between UGT2B15 and UGT2B17 variants and PC risk. These associations with PC risk in men with high Gleason sum, more frequently found in African American men, support the relevance of genetic differences in the androgen metabolism pathway, which could explain, in part, the high incidence of PC among African American men. Larger studies are required

Heat shock proteins and exercise

Uno de mecanismos que posee el organismo para contrarrestar la ruptura de la homeostasis es la producción de proteínas de estrés o heat shock proteins (HSP). Aumentos en la temperatura corporal, en la concentración de Ca2+ y de ciertos corticoides así como disminuciones del pH, de la glucemia y del glucógeno se presentan, junto a la isquemia, como los principales agentes desencadenantes de la respuesta de HSP. La práctica de ejercicio físico integra gran parte de estos factores, lo que provoca una clara liberación de HSP muscular tras diferentes tipos de esfuerzos. Factores como la edad, el género, el nivel de entrenamiento, la intensidad y el volumen del ejercicio realizado o el tipo de fibra muscular, parecen tener una relación directa con las adaptaciones biológicas relacionadas con las HSP. Son necesarios más estudios para definir con mayor exactitud la función biológica de las HSP vinculada con el ejercicio físico

Using whole body vibration to improve jump ability in young recreational sportmen

The whole body vibrations (WBV) it is nowadays one of the most widely used methods for improvingthe explosive strength. In this study, 12 subjects participating in recreational physical activity were allocated to a5 sets of 60 s training, using a frequency of 30 Hz, an amplitude of 2.5 mm. and a isometric position (110 °bending knees) on a Galileo Fitness ® (Novotech, Germany) platform. The results showed an increase in SJ(+1.76 ± 4.05 cm) and CMJ (+1.10 ± 3.20 cm) in the post-test conducted just after the vibration. The values of the post-test performed 30 minutes after the squat jump remained above the ones of pre-test but just below the ones of the immediate post-test (+0.42 ± 4.43 cm). By contrast the values in the counter movement jump drop below the pre-test ones (-0.12 ± 2.45 cm). Based on these data it seems that when the frequency is not high it is necessary to use a greater amplitude in order to achieve the desired effects. The effect achieved after the vibration is transient, not remaining after 30 minutes

HIV test-seeking before and after the restriction of anonymous testing in North Carolina.

OBJECTIVES: This study assessed the impact on HIV test-seeking of North Carolina's restriction of anonymous testing to 18 of its 100 counties as of September 1, 1991. METHODS: Trends from 4 months prerestriction to the 16-month restriction period in counties retaining vs counties eliminating anonymous testing were compared. RESULTS: HIV testing increased throughout the state, but more rapidly where anonymous testing was retained than elsewhere: 64% vs 44%. These differences held for all sociodemographic subgroups and were most pronounced among adolescents and African Americans and other non-Whites. CONCLUSIONS: The data are consistent with a detrimental effect of elimination of anonymous testing, although confounding from differences in AIDS awareness or in repeat tests is possible

Cardiovascular risk factors, caloric intake and practice of physical activity in college students. A preliminary study.

The aim of this investigation were to determine the level of physical activity practice and to define the presence of cardiovascular risk factors associated with body composition and caloric intake in college students. A total of 81 college students (38 and 41 females and males, respectively) were submitted to a complete evaluation that consisted of an analysis of food-intake behavior, measures of several body composition variables (height, weight, body mass index, fat and muscle mass, waist and hip circumferences, waist-hip ratio, and sum of 6 skinfolds), blood pressure assessment, and physical activity level calculation. The results show sex differences in blood pressure and body composition variables; although an optimal food-intake patterns, a high level of physical activity practice and the absence of cardiovascular risk factors seem to generate healthy profiles in this population. Key words:cardiovascular risk factors, food-intake patterns, physical activity, college students

Interplay of gestational parent exposure to ambient air pollution and diet characteristics on preterm birth

Background: Despite many efforts, preterm birth (PTB) is poorly understood and remains a major public health problem in the United States. Toxicological work suggests gestational parent (GP) diet may modify the effect of ambient pollutants on birth outcomes. We assessed risk of PTB in humans in relation to fine particulate matter (PM2.5), ozone (O3), and nitrogen dioxide (NO2) and variation by diet. Methods: 684 GP-singleton infant pairs in the Newborn Epigenetics Study prospective birth cohort were attributed ambient air pollutant exposures for each trimester based on residence. Total energy intake, percent of energy intake from saturated fat, and percent of energy intake from total fat were dichotomized at the 75th percentile. &gt;We used log binomial regressions to estimate risk ratios (RR (95%CI)) for PTB by pollutant interquartile ranges, adjusting for GP age, pre-pregnancy body mass index, GP race/ethnicity, GP education, season of conception, household income, and each diet factor. We assessed departure from additivity using interaction contrast ratios (ICRs). We addressed missing covariate data with multiple imputation. Results: Point estimates suggest that O3 may be inversely associated with PTB when exposure occurs in trimester 2 (min RR: 0.77, 95% CI: 0.39, 1.49), but may be harmful when exposure occurs in trimester 3 (max RR: 1.51, 95% CI: 0.62, 3.64). Additionally, PM2.5 may be inversely associated with PTB when considered with total fat and saturated fat in trimester 2. Imprecise ICRs suggest departure from additivity (evidence of modification) with some pollutant-diet combinations. Conclusions: While confidence intervals are wide, we observed potential modification of pollutant associations by dietary factors. It is imperative that large cohorts collect the required data to examine this topic, as more power is necessary to investigate the nuances suggested by this work