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No abstract is provided for this article.

Excess visceral adipose tissue (AT) and hyperinsulinemia are important correlates of an altered lipoprotein profile. It has also been reported that testosterone, adrenal C19 steroids and sex hormone-binding globulin (SHBG) concentrations are associated with plasma lipoprotein levels. The aim of the present study was to investigate the relative contributions of endogenous steroid hormone and SHBG levels, of visceral AT accumulation measured by computed tomography, and of fasting insulin and free fatty acid (FFA) concentrations to the variation of plasma lipoprotein levels in men. For this purpose, plasma concentrations of testosterone, dehydroepiandrosterone (DHEA), androstene-3β,17β-diol (Δ5-DIOL), androstenedione (Δ4-DIONE), estrone and estradiol, as well as SHBG levels were determined in a sample of 76 men covering a wide range of body fatness values. Higher testosterone levels were associated with a more favorable lipoprotein profile as it showed significant correlations with triglyceride (TG), total cholesterol and LDL-cholesterol (LDL-C) concentrations (r=−0.25, −0.25 and −0.27, respectively; P<0.05). Higher plasma adrenal C19 steroid levels were also associated with a favorable lipoprotein profile as DHEA, Δ4-DIONE and Δ5-DIOL levels were negatively correlated with total cholesterol (r=−0.24, −0.33 and −0.24, respectively; P<0.05) and LDL-C (r=−0.23, −0.31 and −0.28, respectively; P<0.05). SHBG levels were negatively correlated with TG concentrations (r=−0.33; P<0.005) whereas Δ 5-DIOL, testosterone and SHBG were negatively correlated with apolipoprotein B levels (−0.32≤r≤−0.43; P<0.005). Statistical adjustment for visceral AT area, fasting insulin, fasting free fatty acid (FFA) levels and total body fat mass eliminated most of the correlations between steroid and lipoprotein levels, while SHBG remained significantly correlated with lipoprotein concentrations after such adjustments. Multivariate analyses revealed that SHBG, Δ4-DIONE, Δ5-DIOL and metabolic variables all contributed to the variance in plasma lipoprotein concentrations (from 10 to 29% of explained variance). Visceral AT, fasting FFA and insulin levels as well as SHBG concentrations appeared to be independent correlates of lipoprotein concentrations. Thus, metabolic and anthropometric variables examined in the present study could have represented important confounding factors in previous studies which have examined the relationship of steroid hormones to plasma lipoprotein concentrations.

The melanocortin system includes five receptors (MC1R to MC5R), and mouse and human MC4R has been shown to be involved in the regulation of feeding, and mouse MC3R in body composition. To verify a possible similar effect of MC3R in humans, we analyzed one insertion and one single nucleotide polymorphism by restriction fragment length polymorphisms (RFLP), and a microsatellite (D20S32e) in relation to body composition and glucose metabolism.Eight hundred twelve subjects of the Québec Family Study (QFS) cohort were analyzed for body composition, food intake, and energy metabolism phenotypes. Southern Blot with the complete MC3R cDNA was used to detect a new +2138InsCAGACC variant by Pst1 restriction. PCR-RFLP with BsaJ1 was used to type amino acid polymorphism V81I arising from a G241A nucleotide change. PCR and automatic DNA sequencers were used for the analysis of the TG dinucleotide repeat D20S32e located between -1933/-1892 of MC3R. In a covariance analysis among genotypes, phenotypes were adjusted for age and sex as covariates. Food intake and energy metabolism phenotypes were also adjusted for body mass index (BMI), and leptin and abdominal fat, as assessed by a computed tomography scan, for fatness using six skinfold thicknesses.An association between the +2138InsCAGACC MC3R polymorphism was observed with fat mass (FM), percent body fat (%FAT), and total abdominal fat (ATF). Homozygote subjects for the +2138 insertion variant allele in normal weight (BMI < 25 kg/m(2)) and overweight (25 < or = BMI < 30 kg/m(2)) subjects showed a similar level of fatness despite the overall difference in BMI. In normal weight, homozygotes for the insertion allele showed higher mean values than heterozygotes and homozygotes for wild-type allele without insertion (%FAT: 24.0 +/- 1.1 versus 19.3 +/- 0.9 and 20.5 +/- 0.8, p = 0.0005; FM: 15.7 +/- 0.9 kg versus 11.7 +/- 0.7 kg and 12.6 +/- 0.6 kg, p = 0.0003). In contrast, overweight subjects homozygote for the variant allele showed lower mean values (%FAT: 27.0 +/- 1.2 versus 31.4 +/- 0.8 and 30.9 +/- 0.7, p = 0.002; FM: 18.3 +/- 1.0 kg versus 22.8 +/- 0.8 kg and 22.0 +/- 0.6 kg, p = 0.0001). This resulted in a similar level of body fat between both BMI groups for subjects homozygote for the insertion allele versus wild-type allele carriers (%FAT: +/-2-3% versus +/-10-12%; FM: +/-2 kg versus +/-9-11 kg). In obese subjects (BMI > or = 30 kg/m(2) ), a lower level of ATF was seen (-15%, p = 0.002). Other polymorphisms and phenotypes tested showed no association.A new 12138InsCAGACC MC3R polymorphism is associated with the level of adiposity and with body fat partitioning in interaction with corpulence in humans.

No abstract is provided for this article.

Background The true causes of the obesity epidemic are not well understood and there are few longitudinal population-based data published examining this issue. The objective of this analysis was to examine trends in occupational physical activity during the past 5 decades and explore how these trends relate to concurrent changes in body weight in the U.S. Methodology/Principal Findings Analysis of energy expenditure for occupations in U.S. private industry since 1960 using data from the U.S. Bureau of Labor Statistics. Mean body weight was derived from the U.S. National Health and Nutrition Examination Surveys (NHANES). In the early 1960's almost half the jobs in private industry in the U.S. required at least moderate intensity physical activity whereas now less than 20% demand this level of energy expenditure. Since 1960 the estimated mean daily energy expenditure due to work related physical activity has dropped by more than 100 calories in both women and men. Energy balance model predicted weights based on change in occupation-related daily energy expenditure since 1960 for each NHANES examination period closely matched the actual change in weight for 40–50 year old men and women. For example from 1960–62 to 2003–06 we estimated that the occupation-related daily energy expenditure decreased by 142 calories in men. Given a baseline weight of 76.9 kg in 1960–02, we estimated that a 142 calories reduction would result in an increase in mean weight to 89.7 kg, which closely matched the mean NHANES weight of 91.8 kg in 2003–06. The results were similar for women. Conclusion Over the last 50 years in the U.S. we estimate that daily occupation-related energy expenditure has decreased by more than 100 calories, and this reduction in energy expenditure accounts for a significant portion of the increase in mean U.S. body weights for women and men.

Background. The purpose of the study was to examine the 7-year stability of systolic (SBP) and diastolic (DBP) blood pressures in the Canadian population. Methods. The sample included 1,503 participants 7–69 years of age from the 1981 Canada Fitness Survey who were remeasured in Campbell's Survey of 1988. Both SBP and DBP were adjusted for the effects of body mass index (BMI) using regression procedures. Results. Interage correlations from baseline to follow-up ranged from −0.17 to 0.61 for SBP and from −0.22 to 0.51 for DBP. With few exceptions, correlations were positive and significant, and were highest and most consistent in adulthood. Further, between 27 and 39% of participants in the upper or lower quintiles in 1981 remained there in 1988. There were few differences in adiposity between those who remained in the upper or lower quintiles and those who did not. One exception was that males who remained in the upper quintile of SBP had greater values for BMI, sum of skinfolds, and waist circumference at baseline. Among adults, the best predictor of future blood pressure was baseline blood pressure, which accounted for between 12 and 34% of the variance in follow-up blood pressure, followed by age, follow-up BMI, and, in females, baseline physical activity levels. Conclusions. Blood pressure demonstrated low to moderate stability over 7 years in Canada, and baseline level of adiposity was related to the stability of SBP in males.

No abstract is provided for this article.

There is growing evidence that cortisol secretion and/or metabolism is associated with cardiovascular risk factors. Previous studies have shown that cardiovascular risk factors are associated with stimulated cortisol secretion and not with basal cortisol secretion. With the restriction enzyme Tth111I, a variant of the 5′-flanking region of the glucocorticoid receptor gene locus (GRL) was identified. The genotypes were compared for measurements of cortisol secretion and cardiovascular risk factors in a cohort (N = 284) of randomly selected middle-aged men. The frequency of the 3.4/3.4-, 3.4/3.8-, and 3.8/3.8-kilobase (kb) genotypes was 49.6%, 41.4%, and 9.0% respectively. The 3.8-kb homozygotes showed higher total and evening cortisol levels with a trend for elevated levels over the day. Neither stimulated or suppressed cortisol secretion nor anthropometric, endocrine, metabolic, and hemodynamic cardiovascular risk factors were significantly different among the genotypes. Since the polymorphism studied herein is localized at the 5′-flanking region of the GRL, the results suggest that elevated basal cortisol secretion is associated with a polymorphism of the promoter region.

The relations between habitual physical activity (PA), fibrinogen gene polymorphisms and plasma fibrinogen were investigated in 191 postmenopausal women. Subjects who reported PA at least 4 times/week had lower fibrinogen level (3.19 g/l; 95% CI 3.10; 3.27) than women reporting PA 2-3 times/week (3.43 g/l; 3.29; 3.58) or sedentary subjects (3.64 g/l; 3.33; 3.94). There were no differences in plasma fibrinogen across the alpha-fibrinogen (RsaI, TaqI) or beta-fibrinogen (MnlI, BclI, HindIII) genotypes, the frequencies of which were in a Hardy-Weinberg equilibrium. An interaction between RsaI, which was in complete linkage disequilibrium with TaqI, and PA on plasma fibrinogen was observed, even after adjustments for BMI, smoking and medication (p = 0.024). Among women homozygous for the common RsaI allele, the physically most active had lower fibrinogen level (p <0.001) compared to the physically less active subjects. These results suggest that, in postmenopausal women, the relation between physical activity and plasma fibrinogen is modulated by genetic variation in the alpha-fibrinogen gene.

Previous work revealed the potential of an inclined plate settler (IPS) for water treatment in emergency relief applications. Whilst preliminary data demonstrated the tested IPS prototype’s capacity to achieve stable turbidity reductions, further optimisation was warranted. This paper reports on the optimisation and preliminary field testing of an IPS prototype. Trials revealed that after system modification, treatment objectives with regards to turbidity reductions (i.e. < 5 NTU) could be achieved. Such positive results were largely due to the addition of a hydraulic flocculation (conditioning) stage.

A previously reported blood pressure (BP) quantitative trait locus on rat Chromosome 1 was isolated in a short congenic segment spanning 804.6 kb. The 804.6 kb region contained only two genes, LOC306664 and LOC306665. LOC306664 is predicted to translate into A Disintegrin-like and Metalloproteinase with Thrombospondin Motifs-16 (Adamts16). LOC306665 is a novel gene. All predicted exons of both LOC306664 and LOC306665 were sequenced. Non-synonymous variants were identified in only one of these genes, LOC306664. These variants were naturally existing polymorphisms among inbred, outbred and wild rats. The full-length rat transcript of Adamts16 was detected in multiple tissues. Similar to ADAMTS16 in humans, expression of Adamts16 was prominent in the kidney. Renal transcriptome analysis suggested that a network of genes related to BP was differential between congenic and S rats. These genes were also differentially expressed between kidney cell lines with or without knock-down of Adamts16. Adamts16 is conserved between rats and humans. It is a candidate gene within the homologous region on human Chromosome 5, which is linked to systolic and diastolic BP in the Quebec Family Study. Multiple variants, including an Ala to Pro variant in codon 90 (rs2086310) of human ADAMTS16, were associated with human resting systolic BP (SBP). Replication study in GenNet confirmed the association of two variants of ADAMTS16 with SBP, including rs2086310. Overall, our report represents a high resolution positional cloning and translational study for Adamts16 as a candidate gene controlling BP.