Comparison of regional fat measurements by dual-energy X-ray absorptiometry and conventional anthropometry and their association with markers of diabetes and cardiovascular disease risk.

BACKGROUND/OBJECTIVES: Fat distribution is a strong and independent predictor of type 2 diabetes (T2D) and cardiovascular disease (CVD) and is usually determined using conventional anthropometry in epidemiological studies. Dual-energy X-ray absorptiometry (DXA) can measure total and regional adiposity more accurately. Nonetheless, whether DXA provides more precise estimates of cardiovascular risk in relation to total and regional adiposity is not known. We determined the strength of the associations between DXA- and conventional anthropometry determined fat distribution and T2D and CVD risk markers. SUBJECTS/METHODS: Waist (WC) and hip circumference (HC) and DXA was used to measure total and regional adiposity in 4950 (2119 men) participants aged 29-55 years from the Oxford Biobank without pre-existing T2D or CVD. Cross-sectional associations were compared between WC and HC vs. DXA-determined regional adiposity (all z-score normalised) with impaired fasting glucose, hypertriglyceridemia, hypertension and insulin resistance (IR). RESULTS: Following adjustment for total adiposity, upper body adiposity measurements showed consistently increased risk of T2D and CVD risk markers except for abdominal subcutaneous fat in both sexes, and arm fat in men, which showed protective associations. Among upper adiposity depots, visceral fat mass showed stronger odds ratios (OR) ranging from 1.69 to 3.64 compared with WC 1.07-1.83. Among lower adiposity depots, HC showed modest protection for IR in both sexes (men: OR 0.80 (95% confidence interval 0.67, 0.96); women: 0.69 (0.56, 0.86)), whereas gynoid fat and in particular leg fat showed consistent and strong protective effects for all outcomes in both men and women. The differential effect of body fat distribution on CVD and T2D were more pronounced at higher levels of total adiposity. CONCLUSIONS: Compared with DXA, conventional anthropometry underestimates the associations of regional adiposity with T2D and CVD risk markers. After correcting for overall adiposity, greater subcutaneous fat mass in particular in the lower body is protective relative to greater android or visceral adipose tissue mass.

A common variant in the FTO locus is associated with waist-hip ratio in Indian adolescents.

BACKGROUND: Common variants in the FTO locus, and near MC4R locus, have been shown to have a robust association with obesity in children and adults among various ethnic groups. Associations with obesity traits among Indian adolescents have not been determined. OBJECTIVE: To study the association of rs9939609 (FTO) and rs17782313 (MC4R) to obesity related anthropometric traits in Indian adolescents. METHODS: Subjects for the current study were recruited from a cross-sectional cohort of 1,230 adolescents (age mean ± SD: 17.1 ± 1.9 years) from South India. RESULTS: The variant at the FTO locus was found to be associated with waist-hip ratio (WHR) but not with overall obesity in this population. No significant association was observed for obesity-traits and Mc4R variant rs17782313. CONCLUSION: The common variant of FTO (rs9939609) is associated with body fat distribution during early growth in Indian adolescents and may predispose to obesity and metabolic consequences in adulthood.

Anthropometric measurements for the prediction of the metabolic syndrome: a cross-sectional study on adolescents and young adults from southern india.

OBJECTIVES: To determine which anthropometric measurement correlates best with the metabolic abnormalities associated with the metabolic syndrome in adolescents and young adults. DESIGN: Cross-sectional study. SETTING: Schools, high schools and universities. PARTICIPANTS: 1359 adolescents and young adults aged 14-25 years. MAIN OUTCOME MEASURES: Anthropometric predictors of metabolic abnormalities as classified by International Diabetes Federation definition. RESULTS: The waist circumference (OR 1.56, 95% CI 1.0 to 2.43: p≤0.01) and the abdominal skin fold thickness (OR 1.44, 95% CI 1.02 to 2.04, p≤0.01) above the third quintile cut-offs were found to be significantly associated with metabolic abnormalities. The sensitivity of either one of these measurements in predicting metabolic abnormalities was 66.1% with a negative predictive value of 82.8%. Hyperglycaemia was significantly associated with an abdominal skin fold thickness over the fourth quintile alone (OR 1.63, 95% CI 1.24 to 2.1). All the anthropometric measurements correlated well with elevated triglycerides and hypertension. CONCLUSIONS: In a large community-based cross-sectional survey of subjects aged 14-25 years, the waist circumference and the abdominal skin fold thickness are important predictors of the metabolic abnormalities associated with metabolic syndrome. This simple clinical tool may help in a primary care setting to identify subjects who require a further biochemical evaluation and would considerably reduce the cost of unwarranted testing.

Immune responses to Epstein-Barr virus in individuals with systemic and organ specific autoimmune disorders.

PURPOSE: Autoimmune diseases usually manifest in genetically predisposed individuals following an environmental trigger. There are several viral infections including Epstein-Barr virus (EBV) implicated in the pathogenesis of autoimmune disorders. The aim of this study was to look at the antibody pattern to EBV proteins in the plasma of both systemic and organ specific autoimmune disorders, estimate pro-inflammatory plasma cytokines (IL-8 and TNF-alpha) among these autoimmune patients and compare the observations with those in normal healthy controls. MATERIALS AND METHODS: Samples from 44 rheumatoid arthritis patients, 25 Hashimoto's thyroiditis patients, appropriately age and sex matched healthy controls were tested for EBV IgM antibodies by an immunoblot assay and two cytokines (IL-8 and TNF-alpha) by commercial assays. RESULTS: Among the rheumatoid arthritis patients, 23 (52%) were positive for EBNA1 antibody, while 13 (52%) of the Hashimoto's thyroiditis patients and 12 (30%) of the healthy controls showed similar bands. The intensity of the bands was high in the autoimmune patients when compared to the bands seen in control samples. The difference in the EBNA1 reactivity between rheumatoid arthritis patients and controls were significant (P = 0.038). There was a significant difference in the IgM reactivity to VCAp19 protein between patients and controls (P = 0.011). CONCLUSION: Our study showed an increased EBV activation among the autoimmune patient groups compared to the normal healthy controls. Further studies are required to delineate the association between the aetiology of autoimmune disorders and EBV.

Identification of a novel mycobacterial transcriptional regulator and its involvement in growth rate dependence and stringent control.

A novel transcriptional regulator has been identified in the 400-bp upstream region of the guaA gene of Mycobacterium tuberculosis H37Rv that promotes the expression of lacZ gene in Mycobacterium smegmatis mc(2)155 and M. tuberculosis H37Rv but not in Escherichia coli DH5alpha. PCR-mediated deletion mutagenesis and cloning identified a 120-bp fragment upstream from the guaA gene to be the actual regulator. Primer extension analysis mapped the transcription start site to be the first 'G' residue of the translation start codon GTG of the guaA gene. Electrophoretic mobility shift assay showed strong binding of M. smegmatis RNA polymerase holoenzyme to the 400-bp fragment that expresses lacZ in mycobacterial species and a weak binding to the 280-bp fragment that expresses only in E. coli DH5alpha. Both promoter recombinants revealed varied response in the presence of purine nucleotides and exhibited down-regulation when subjected to amino acid starvation.

Transcriptional analysis of inducible acetamidase gene of Mycobacterium smegmatis.

Isolation and analysis of strong and regulatable promoters of mycobacteria should be useful tools to aid the expression of cloned genes in mycobacteria. In the present study, we have mapped the transcriptional start site of the inducible acetamidase gene of Mycobacterium smegmatis and studied the mechanism of its regulation. Northern blot, reverse transcription-PCR and primer extension analysis studies were used to determine the position of the promoter.