ABSTRACT
BACKGROUND: Biometric information obtained from cross-sectional studies works as a mirror of individual and collective life conditions at a given moment and allows assessment of secular trends in growth. AIM: The purpose of this study was to evaluate growth and growth velocity for height and weight, to determine the BMI and the sexual maturation characteristics of a pre-selected urban sample of subjects from El Yopal and to compare the results with those from others countries. SUBJECTS AND METHODS: In 2000-2001, 1039 schoolchildren (517 girls and 522 boys) were evaluated in the age range of 6-18 years. Low, medium and high socio-economic status (SES) were determined from monthly family income. Sexual development (Tanner-Whitehouse scale) and age of menarche (status quo method) were also determined. The LMS method was used to establish biometric centiles and the general logistic model was used to establish the median age for different stages of puberty. RESULTS: Height, Girls: 155.4 cm, at 17.3 years with maximum yearly increment (myi) of 6.24 cm, at 11.10 years. Boys: 166.9 cm, at 18.0 years with myi of 6.48 cm, at 13.60 years. Weight, Girls: 52.5 kg, at 17.3 years with myi of 4.92 kg, at 11.98 years. Boys: 59.2 kg, at 18.0 years with myi of 4.88 kg, at 12.99 years. BMI at 18.0 years, Girls: 22.16 kg/m(2), Boys: 21.05 kg/m(2). Female puberty by stage of breast B2 began at 10.21 ± 1.16 years (mean ± SD). Male puberty by stage of genitalia G2 began at 11.53 ± 1.07 years. CONCLUSION: The findings show lower height values and lower weight values, except for the Cuban reference, for both sexes; an early onset of puberty in girls and a prolonged puberty in boys when compared with other Caribbean, Central and South American females and males.
Subject(s)
Body Height , Body Mass Index , Sexual Maturation , Adolescent , Age Factors , Biometry , Child , Colombia , Cross-Sectional Studies , Female , Humans , Male , Menarche , Puberty , Socioeconomic FactorsABSTRACT
Waist circumference (WC) is a measure of central adiposity related to elevated risk factor levels in children and adolescents. The aim of the present study was to describe WC percentiles in 7- to 10-year-old Brazilian children and to compare frequencies of obesity and overweight as defined by BMI and frequencies of excess and at risk of abdominal adiposity as defined by WC to the corresponding age and sex data from British references. A representative sample of 2919 schoolchildren of the city of Florianopolis (southern Brazil) was examined. Smoothed WC percentiles were derived using the least mean square method. Frequencies of overweight and obesity and of excess and at risk of abdominal adiposity were assessed using the 91st and 98th centiles of the British references as cut-off points. WC increased with age in both boys and girls, with higher values for boys at every age and percentile level. Nutritional status categories of children assessed by the 91st and 98th British BMI and WC centiles showed moderate agreement (weighted kappa = 0.58). Overweight was more frequent in Brazilian than British children: 15.1 % of girls and 20.1 % of boys were above the 91st percentile of the 1990 BMI for age British references. About one-quarter (22.0 % of girls and 26.9 % of boys) exceeded the 91st percentile of WC British references. The present data could be used to compare WC in children in other populations and may serve as a baseline for future studies of temporal trends in WC in Brazil.
Subject(s)
Adiposity , Obesity/epidemiology , Aging/physiology , Anthropometry/methods , Body Constitution , Body Mass Index , Brazil/epidemiology , Child , Female , Humans , Male , Nutritional Status , Obesity/diagnosis , Overweight , Prevalence , Reference Values , Sex CharacteristicsABSTRACT
The use of microporous membranes has been examined for the recovery of precipitated protein suspensions and related soluble protein. Membrane flux rates and soluble protein transmissions are reported for unstirred batch-cell studies and cross-flow experiments. The unstirred batch-cell gave soluble protein transmissions in the range 80-100% for feeds containing either soluble protein or a mix of soluble and isoelectrically precipitated protein. In all cases a sharp decline in flux was observed which was, for example, considerably greater for soluble protein at its isoelectric point, pH 4.6, than at pH 8.8. The presence of precipitated protein led to a further decrease in flux rate. In cross-flow studies, flux decline was eventually accompanied by a significant decline in soluble protein transmission. The flux protein-transmission characteristics of microporous membranes are discussed in terms of the interaction of the soluble and precipitated protein with the membrane.
