Short sleep duration and adiposity in Chinese adolescents.

Objective: To investigate the relationship between sleep duration and adiposity measurements in rural Chinese adolescents.

Methods: This report is based on a cross-sectional analysis of 500 Chinese adolescent twins. Anthropometric measurements and direct adiposity measurements using dual-energy X-ray absorptiometry (DEXA) were taken for all subjects.

Patterns and interrelationships of body-fat measures among rural Chinese children aged 6 to 18 years.

Objectives: Our goal was to compare BMI and waist circumference with dual-energy radiograph absorptiometry-based measures of adiposity and to describe the pattern and interrelations of these surrogate and direct adiposity measures in prepubertal and pubertal rural Chinese children.

Methods: This was a cross-sectional study of 2493 children aged 6 to 18 years from a population-based cohort of twin pairs. Dual-energy radiograph absorptiometry-based measurements included total body fat, percentage of body fat, trunk fat, and percentage of trunk fat.

Efficacy of folic acid supplementation in stroke prevention: a meta-analysis.

Background: The efficacy of treatments that lower homocysteine concentrations in reducing the risk of cardiovascular disease remains controversial. Our aim was to do a meta-analysis of relevant randomised trials to assess the efficacy of folic acid supplementation in the prevention of stroke.

Methods: We collected data from eight randomised trials of folic acid that had stroke reported as one of the endpoints.

Age and gender specific lung function predictive equations provide similar predictions for both a twin population and a general population from age 6 through adolescence.

Background: There have been numerous studies of asthma in twins, but no study has evaluated whether lung function predictive models yield similar results between twin and general populations. We sought to evaluate this in late childhood and adolescent subjects.

Methods: We generated cross-sectional, sex- and age-specific regression models of FEV(1), and FVC, in a community-based cohort of 3140 healthy, non-smoking Chinese twins using generalized estimating equations to adjust for correlations within twin pairs.

Menstrual cycle lengths and bone mineral density: a cross-sectional, population-based study in rural Chinese women ages 30-49 years.

Introduction: The menstrual cycle involves periodic fluctuations in estrogen and progesterone levels. Longer cycles have been associated with longer follicular phase, delayed estrogen peak and a lower mean oestradiol level of the entire cycle.

Methods: We hypothesized that prolonged menstrual cycle length is associated with decreased bone mineral density (BMD) in a population of pre- and perimenopausal women.

Polymorphism in maternal LRP8 gene is associated with fetal growth.

Fetal growth restriction (FGR) affects >200,000 pregnancies in the United States annually and is associated with increased perinatal mortality and morbidity, as well as poorer long-term health for infants with FGR compared with infants without FGR. FGR appears to be a complex trait, but the role of genetic factors in the development of FGR is largely unknown. We conducted a candidate-gene association study of birth weight and FGR in two independent study samples obtained at the Boston Medical Center.