Explaining body composition by some covariate factors among the elderly Bengalee Hindu women of Calcutta, India.

Understanding the changes in body composition with passage of time and factors associated with them will help to improve our knowledge and understanding about these processes and could guide in the prevention of functional limitations and formulation of better health care among the elderly. The present cross-sectional work was under taken to study the effect of age, menopause, age at first conception, educational level and physical activity in explaining body composition among 200 elderly (55 years and above) Bengalee Hindu women of Calcutta, India. Body composition measures namely percentage of body fat (PBF), fat mass index (FMI), and fat free mass index (FFMI) were calculated from skinfolds thickness using standard equations. Multiple regression analyses of body composition variables by covariate factors revealed that Age, age of onset of menopause, age at first conception, educational level and frequency of walking cumulative explains 35%, 28% and 21% of PBF, FMI and FFMI respectively. Present study revealed that beside age, both biosocial (age of onset of menopause, age at first conception, education level) and physical activity as measured by brisk walking have significant contribution in explaining body composition among elderly females. Significant negative impact of physical activity on PBF, FMI and positive impact on FFMI in the present study were also evident. Therefore, brisk walking could be useful to increase body's fat free mass.

Comparison of anthropometric characteristics between normotensive and hypertensive individuals among a population of Bengalee Hindu elderly men in Calcutta, India.

A comparative investigation of 99 normotensive and 111 hypertensive Bengalee Hindu elderly men (aged 55 years and above) of Kalighat, South Calcutta, India, was undertaken to study differences in levels of adiposity, body fat distribution and body composition between these two groups. Results revealed that there were significant differences between normotensive (NT) and hypertensive (HT) subjects in the mean values for weight (p < 0.05), body mass index (BMI, p < 0.01); waist (p < 0.001) and hip circumferences (p < 0.05); waist-hip ratio (WHR, p < 0.001), conicity index (CI, p < 0.01) and fat free mass (FFM, p < 0.001). Percentile distributions for all these variables and indices showed consistently higher values among the HT patients as compared with NT subjects. However, the frequency of obesity (BMI > or = 25) was similar (NT = 6.1%, HT = 11.7%) in both groups. Thus, these results indicated that there existed significant differences in central adiposity and FFM between NT and HT subjects although their level of obesity was similar. Hypertensive individuals have significantly enhanced levels of central body fat distribution.

A twin study of the structure of human hair medulla.

The genetic basis of hair medulla was studied by the twin method. Hair samples from 17 pairs of monozygotic (9 female and 8 male), 23 pairs of like-sex dizygotic (6 female and 17 male) and 8 pairs of unlike-sex dizygotic twins were utilized and the number of hair strands examined was 9,600. The mean intrapair differences indicate the presence of a strong genetic basis of the character concerned.

Genetic basis of hair medulla by twin study.

Data on the incidence of medulla of human head hair based on 9,600 strands examined from 48 pairs of zygosity--determined German twins were quantified as medullary ratio and subjected to variance analysis to give information about genetic significance of the character concerned. The results of F test and heritability estimate yielded significant values indicating the presence of a strong genetic component of variability in the incidence of medulla of human head hair. Sex influence upon the character is found to be absent.

Genetic basis of human scalp hair weight: a twin study.

Human scalp hair weight has been measured in 48 pairs of German twins of known zygosity. Variance analysis indicates a strong genetic component in variability in human scalp hair weight. No sex variation upon the character is found.

Genetic basis of hair histomorphological variables.

The genetic basis of scalp hair histomorphological variables, such as incidence of medulla, diameter, area of cross-section, cross-sectional index, and weight has been examined in a Bengalee hair sample (India) by family study. The results of correlation analysis between different combinations of parents and offspring together with sibs indicate the involvement of a significant genetic component in variability. The estimates of heritability based on regression coefficients of parent--child are 0.725 (incidence of medullation), 0.534 (diameter), 0.466 (area of cross-section), 0.673 (cross-sectional index), and 0.369 (weight). Moreover, there is little evidence of X-linkage involved in the hair variables.

Variation in hair histological variables: medulla and diameter.

Two hair histological variables, the incidence of medullation and diameter, have been dealth with in twelve populations belonging to different ethnic groups and living in different geographical areas. Results of the F test comparing within-individual variance, between-individual variance and between-population variance of the hair variables concerned indicate that differentiation of various populations is possible. Sex differences for medulla and diameter of hair are observed in some populations included in the present study.

Efficient sequential search of genetic systems for diagnosis of twin zygosity.

Conventionally, the zygosity of twins into monozygotic (MZ) and dizygotic (DZ) is determined by utilizing several blood groups or other genetic markers. Existence of many blood groups or other genetic markers raises the crucial problem of choosing minimum number of blood groups and applying them in a sequence with minimum cost offering maximum effectiveness in classifying the twins by zygosity. In this note, a statistical approach to this problem is made and a solution provided. The efficient sequential search procedure utilizing the gene frequency of four blood groups from the German population of Nordrhein-Westfalen province and applying the results to a twin set of 72 pairs (32 MZ and 40 DZ) of the same population indicates that efficient sequences with 3 and 4 blood groups are AB0----P----Rh and AB0----P----Rh----MNSs, respectively. Further, it is understood that the efficient sequence for zygosity determination will be differing from population to population. As gene frequencies of blood systems differ in the various populations, this will effect the probability that a DZ twin pairs is concordant for a specific marker. Moreover, the relative cost may also turn out to be a decisive factor in the determination of the best sequence. Hence, indiscriminate use of several conventional blood group systems in the determination of zygosity of twins from a particular population should be discontinued. The formulae developed in this note are quite general and the procedure explained can easily be generalized to other situations.

Brief communication: Choice of washing method of hair samples for trace element analysis in environmental studies.

Determination of inseparable exogenous and endogenous levels of toxic trace elements such as lead in human scalp hair has been used to understand and assess population exposure to such elements. For any such analysis, washing of the hair samples to remove superficial contamination is the foremost requirement. However, the use of such washing methods prior to elemental analysis removes minute quantities of trace elements from the hair strands. This degree of loss is dependent on the washing method employed. In the present study, the element lead has been determined in human scalp hair after three methods of hair washing. It is apparent that the nonionic detergent-acetone method is best suited for securing valid lead analysis results in human scalp hair.

Twinning rate in the Muslim population of West Bengal.

Total birth records for the Bengalee Muslim population (BMP) and the Bengalee Hindu caste population (BHCP) for the period 1980-1988 were 17,720 and 119,107 respectively. Of these, the number of twin pairs were 363 BMP and 1,229 BHCP. These data were obtained from the registers of the following hospitals: Islamia Hospital, NRS Medical College and Hospitals and RG Kar Medical College and Hospitals, Calcutta and Medinipore Sadar Hospital, West Bengal, India. The twinning rates found were 20.48 and 10.57 per thousand deliveries in the BMP and BHCP respectively. The proportion of twins, 0.02048, in the BMP was significantly higher (Z = 12.38, p < or = 0.01) than that in the BHCP, 0.01057. This finding of a higher twinning rate in the BMP is corroborated by the fact that available data on the Muslim population of Srinagar in Kammu and Kashmir, and Lucknow and Kanpur in Uttar Pradesh show higher twinning rates than the other populations of India. This increased twinning rate may be due to the greater amount of inbreeding in the BMP.