The contribution of α<Subscript>1B</Subscript>-adrenoceptor subtype in the renal vasculature of fructose-fed Sprague–Dawley rats

Purpose  

Fructose feeding induces a moderate increase in blood pressure, insulin resistance, and hyperinsulinemia. This study investigated the role of α_1B-adrenoceptor subtype in the control of renal hemodynamic responses to exogenously administered angiotensin II (Ang II) and a set of adrenergic agonists in a model of high fructose-fed rats.     

Urinary α<Subscript>1</Subscript>-microglobulin excretion as biomarker of renal toxicity in trichloroethylene-exposed persons

Objectives Concern on human renal toxicity and carcinogenicity of trichloroethylene is based on findings of increased incidences of renal cell cancers in persons with long-lasting and high occupational exposures to this solvent. The full tumour development is likely to require promotional stimuli, by repetitive episodes of high peak exposures to trichloroethylene, leading to nephrotoxicity. This process is visualised by the excretion of tubular marker proteins in the urine of exposed persons. For this purpose, surveillance of ₁-microglobulin excretion is being suggested by the Deutsche Forschungsgemeinschaft.Methods The present study assessed the applicability of ₁-microglobulin as a biomarker of proximal tubule damage in the prevention of nephrotoxicity by trichloroethylene exposures. For this purpose, ₁-microglobulin excretions were assessed in trichloroethylene-exposed and non-exposed subgroups of both cases (diseased with renal cancer) and controls (not diseased with renal cancer) of a recent case–control study.Results The median of ₁-microglobulin excretions in non-exposed persons was below the detection limit, but it was clearly elevated in exposed persons. The Wilcoxon rank sum test showed a significant difference (P=0.0090). Consistent with the underlying concept, renal cell cancer cases who had been exposed to trichloroethylene had higher ₁-microglobulin excretions than non-exposed cases (P=0.0005) and also had higher ₁-microglobulin excretions than exposed controls (P=0.0004). Of 20 trichloroethylene-exposed renal cell cancer cases only three (15%) displayed a normal ₁-microglobulin excretion of <5 mg/l. By contrast, 41 (52%) out of 79 non-exposed renal cancer cases showed normal excretions of the biomarker.Conclusion The present data are in agreement with the concept of pathogenesis of renal cell cancers developing under high (suggested: >500 ppm peak exposures) and long-term (several years) exposure to trichloroethylene. They also visualise the potential value of ₁-microglobulin excretion as a routine biomarker of renal toxicity that may be used in the medical surveillance of trichloroethylene-exposed persons.     

Association of Heart Rate Variability of the Elderly with Personal Exposure to PM<Subscript>1</Subscript>, PM<Subscript>1–2.5</Subscript>, and PM<Subscript>2.5–10</Subscript>

Environmental epidemiologic studies have shown that elderly people are susceptible to particulate air pollution. The decreases in heart rate variability are important indices of health effect caused by particulate matter. The objective of this study was to investigate the effects of submicron particle (PM₁), PM_1–2.5, and coarse particle (PM_2.5–10) on heart rate variability parameters in the elderly. Results of our study indicated that short-term and medium-term PM exposures were associated with the reduction of heart rate variability in the elderly, with stronger effects found for coarse particles in comparison with particles of other size ranges.     

Determination of Aflatoxin M<Subscript>1</Subscript> in Breast Milk Samples in Tabriz–Iran

The aim of this study was to examine the exposure of lactating mothers to aflatoxins using aflatoxin M₁ in breast milk as a biomarker for exposure and to detect its determining factors and possible effects on child growth. A 9% sample of 2022 lactating women who exclusively breastfed their infants, including 91 lactating women of urban areas of Tabriz city and 91 lactating women of its rural areas were recruited by a geographical clustered sampling method. Breast milk samples and information on food intake were collected from subjects using structured food-frequency questionnaire. Extraction of AFM₁ was performed with the ELISA test procedure. Aflatoxin M₁ was detected in breast milk of 20 out of 91 mothers (22%) in concentrations of 6.96 ± 0.94 (pg/ml) in rural areas. Aflatoxin M₁ contamination was not present in samples of urban areas. The presence of aflatoxin M₁ was significantly associated with consumption of local milk (β = 0.71, P < 0.001) and stunted growth in children (β = −0.31, P < 0.015). These findings emphasize the need for developing strategies to reduce exposure to aflatoxin, possibly involving interventions targeted at reducing contamination of foods.     

Effect of dietary supplementation on the prognostic value of urinary and serum 8-isoprostaglandin F2<Subscript>α</Subscript> in chemically-induced mammary carcinogenesis in the rat

Backround  

The aim of the present study was to assess the effects of zinc or copper and polyphenolic compounds on the 8-isoprostaglandin F_2α concentration in the serum and urine of rats with mammary cancer (adenocarcinoma) induced with 7,12-dimethylbenz[a]antracene. The research focused on the kinetics of alterations in urinary 8-isoPGF_2α at the early stage of carcinogenesis as well as the influence of dietary factors on the process. The impact of selected compounds on the intensity of DMBA - induced carcinogenesis was also assessed.     

Carbonaceous Species of PM<Subscript>2.5</Subscript> in Megacity Delhi,India During 2012–2016

Organic carbon (OC) and elemental carbon (EC) in PM_2.5 were estimated to study the seasonal and inter-annual variability of atmospheric total carbonaceous aerosols (TCA) at an urban site of megacity Delhi, India for 5 years from January, 2012 to December, 2016. The annual average (±?standard deviation) concentrations of PM_2.5, OC, EC and TCA were 128?±?81, 16.6?±?12.2, 8.4?±?5.8 and 34.5?±?25.2 µg m^?3, respectively. During the study, significant seasonal variations in mass concentrations of PM_2.5, OC, EC and TCA were observed with maxima in winter and minima in monsoon seasons. Significant correlations between OC and EC, and OC/EC ratio suggested that vehicular emissions, fossil fuel combustion and biomass burning could be major sources of carbonaceous aerosols of PM_2.5 at the sampling site of Delhi, India.     

A high-fat meal impairs muscle vasodilatation response to mental stress in humans with Glu27 β<Subscript>2</Subscript>-adrenoceptor polymorphism

Background  

Forearm blood flow responses during mental stress are greater in individuals homozygous for the Glu27 allele. A high-fat meal is associated with impaired endothelium-dependent dilatation. We investigated the impact of high-fat ingestion on the muscle vasodilatory responses during mental stress in individuals with the Glu27 allele and those with the Gln27 allele of the β₂-adrenoceptor gene.     

Physiological Stress of High NH<Stack><Subscript>4</Subscript><Superscript>+</Superscript></Stack> Concentration in Water Column on the Submersed Macrophyte <Emphasis Type="Italic">Vallisneria Natans</Emphasis> L.

The submersed macrophyte, Vallisneria natans L., was cultured in laboratory with NH₄⁺-enriched tap water (1 mg L⁻¹ NH₄-N) for 2 months and the stressful effects of high ammonium (NH₄⁺) concentrations in the water column on this species was evaluated. The plant growth was severely inhibited by the NH₄⁺ supplement in the water column. The plant carbon and nitrogen metabolisms were disturbed by the NH₄⁺ supplement as indicated by the accumulation of free amino acids and the depletion of soluble carbohydrates in the plant tissues. The results suggested that high NH₄⁺ concentrations in the water column may hamper the restoration of submersed vegetation in eutrophic lakes.     

How does a 10-fold pulse increase of aircraft-related NO<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript> impact the global burdens of O<Subscript>3</Subscript> and secondary organic aerosol (SOA)?

Aircraft emissions are an important and growing global source of nitrogen oxides (NO _x ). At cruising altitude, the atmosphere is particularly NO _x -sensitive and aircraft emissions contribute to ozone (O₃) production and oxidation of volatile organic pollutants that ultimately produce secondary organic aerosol (SOA). Rapid growth of the global fleet of aircraft and the number of flights require a careful investigation on the atmospheric impact of potential increases in total aircraft-emitted NO _x . In this study, we simulated atmospheric composition before, during and after two 10× pulses of total aircraft NO _x emissions, one in winter and one in summer of 2007. Results showed that the initial NO _x enhancement (up to 3.25% averaged over the globe) was removed after the first 2 months and the change in O₃ burden increases for 5 months (up to 3.1 and 2.7% averaged over the globe, respectively, for winter and summer perturbations). The NO _x and O₃ enhancements follow previously observed temporal patterns, but SOA showed strong season-specific results. During the summer, the NO _x pulse decreased total secondary organic gases (SOGs) and SOA burdens, suggesting an inverse relationship with enhanced oxidation. During the winter, the NO _x pulse increased the SOG and SOA burdens with SOA lagging SOG. The SOG enhancement has a spatio-temporal pattern similar to NO _x . The highest changes in SOA and SOG burdens of different regions during the summer and winter pulse increases were below 1.6%. However, O₃ pollution with burden increases as high as 8% in the winter months and 6% in the summer months of the northern hemisphere may even represent an air quality concern.     

Ambient PM<Subscript>10</Subscript> impacts brought by the extreme flooding event of March 24–26, 2015, in Copiapó, Chile

On March 24–26, 2015, the Chilean city of Copiapó (27° 22′ S, 70° 20′ W), located in the hyperarid Atacama Desert, suffered an intense flooding brought by an extreme, unique rainfall event with a 35-year record of daily precipitation. A receptor model (positive matrix factorization, version 5) analysis, applied to ambient PM₁₀ chemical speciation from three short-term sampling campaigns, resolved four sources: crustal/road dust, sea salt, secondary sulfates, and emissions from Paipote copper smelter located 8 km east of Copiapó. Wind trajectories computed with US NOAA’s Hybrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT) supported the above source identification and explained variability in source contributions. It was found that crustal/road dust increased 50 μg/m³, in April 8–10, 2015, as compared with values in November 2014 and October–November 2015, respectively. This was the dominant PM₁₀ source after the flooding and before debris were cleaned up, being on order of magnitude higher that the other source contributions. The Paipote copper smelter contributed with primary PM₁₀ emissions and secondary sulfates; this combined contribution averaged 11.8 μg/m³. Sea salt contributions contributed an average of 3.3 μg/m³. In normal conditions, crustal/road dust averaged 2.9 μg/m³, but the other resolved sources also contributed with crustal elements as their emissions are transported by winds to Copiapó. The positive matrix factorization solution included an unresolved concentration of 7.4 μg/m³. The small number of samples and the lack of measurements of nitrate, ammonia, and organic and elemental carbon may explain this result. Hence, sources such as secondary nitrates and combustion sources plus fugitive dust from sources surrounding Copiapó might be included in that unresolved concentration.     

The relationship of high PM<Subscript>2.5</Subscript> days and subsequent asthma-related hospital encounters during the fireplace season in Phoenix,AZ, 2008–2012

Exposure to particulate matter less than 2.5 μm in diameter (PM_2.5) exacerbates asthma and increases mortality. In Phoenix, AZ, the highest PM_2.5 values frequently occur during the winter fireplace season and air quality health standards are often exceeded during the Christmas and New Year’s holidays. It was clear that enhanced messaging was needed by air quality and public health authorities to discourage biomass fires (BMF) on days when unhealthful levels of pollution were likely to be caused by that activity. Demonstrating adverse health outcomes would bolster this effort. We conducted this study to evaluate associations between elevated PM_2.5 exposures during the fireplace season and asthma-related hospital admissions in Phoenix; days with average PM_2.5 > 35 μg/m³ were categorized as elevated PM_2.5 exposure. We used hospital discharge data to identify patients with an asthma-related hospital encounter and who lived within an 8-km radius of a PM_2.5 monitor. To estimate the risk of a hospital encounter following an elevated PM_2.5 event, we used generalized estimating equations, specified with a Poisson distribution, and exposure lags of 0–3 days. Controlling for influenza, temperature, humidity, rain, and year, these analyses generated elevated estimates of emergency department visit risk among adults on lag days 2 (relative risk [RR] 1.19; 95 % CI 1.06, 1.34) and 3 (RR 1.20, 95 % CI 1.05, 1.37). Elevated PM_2.5 was not associated with hospital encounters among children. Our findings suggest that adults may be at elevated risk of asthma-related hospital encounters during the fireplace season.     

Source apportionment studies in six Indian cities—drawing broad inferences for urban PM<Subscript>10</Subscript> reductions

PM₁₀ is a critical air pollutant in urban areas of India. Out of 176 cities, 140 exceeded annual PM₁₀ standard of 60 μg m^?3 in 2010. A detailed PM₁₀ source apportionment study was conducted in six Indian cities during 2007–2010, providing insight to urban PM₁₀ issues. Data on emission inventory along with carbon, secondary inorganic aerosol (SIA) and crustal components of ambient PM₁₀ were analyzed to get broad actions for urban PM₁₀ reduction. Road dust and vehicles emerged as two major sources accounting for ~30 to 70 % and ~15 to 20 % of PM₁₀ emissions, respectively. Maximum concentration of EC, SIA, and crustal components varied between 10.3–38.0, 15.5–30.2, and 17.5–40.6 μg m^?3, respectively. Kerbside locations showed higher EC levels. Background SO₄ ^2? and NO₃ ^? levels were ~70–80 % of city average. Controlling dust from road segments with high traffic volume, emissions from heavy duty vehicles, and efficient public transport emerged as key actions. Reducing SO₂ and NO_x emissions from industries in nonattainment cities will reduce SIA. The six-city project represents a large range of activity, geophysical, and meteorological profiles, and as such would represent source mix of many Indian cities and towns. It would, therefore, be reasonable to apply broad inferences from the study to other Indian cities and towns.     

Assessment of heavy metal characteristics and health risks associated with PM<Subscript>2.5</Subscript> in Xi’an,the largest city in northwestern China

Fine particulate matters (PM_2.5) samples were collected in Xi’an, northwestern China, from May 2015 to April 2016. The concentrations, seasonal variations, potential sources, and health risks for personal exposure for ten metallic elements (i.e., Ba, Zn, Cu, As, Ni, Pb, Mn, Cr, Cd, and Hg) bounded to PM_2.5 were determined and assessed in this study. The results showed that the average PM_2.5 mass concentration in Xi’an was 62.1?±?35.0 μg m^?3 during the sampling period. The annual concentration of the total quantified elements was 2459.5?±?1789.8 ng m^?3, with relatively higher values in winter (3334.9?±?1690.9 ng m^?3) and spring (2809.4?±?2465.4 ng m^?3), in comparison of those in summer (1857.6?±?1162.7 ng m^?3) and autumn (1252.5?±?842.4 ng m^?3). Two elements of Ba (678.0?±?684.9 ng m^?3) and Zn (1264.8?±?725.3 ng m^?3) had greater fluctuations in concentrations and were accounted for more than 80% of the concentration of total quantified elements for each season. The concentrations of As in Xi’an exceeded the national standard in China. The enrichment factors (EFs) of most target heavy metals were high, exceeding 100 for Zn, As, Pb, Cd, and Hg, attributed to strong influences from human activities. Moreover, the largest enrichment of heavy metals in PM_2.5 occurred in Xi’an in winter. Principle component analysis (PCA) was applied for source apportionment. Coal and other fuel combustion, vehicle exhaust, and industrial activities were the three major pollution sources which contributed 43.6, 29.9, and 15.3%, respectively, of the total variance of PM_2.5. The health risk assessment showed that the non-cancer risks of As, Pb, and Cr for children were greater than 1, as well as of As for adults. The cancer risks of As and Cr were higher than 1?×?10^?6, indicating that the two elements had high potentials for both non-cancer and cancer risks. Our finding suggests that the PM_2.5 and related heavy metal pollutions in Xi’an were serious and posed high potential health risks. Effective controls and measures should be established in the studied area.     

Antioxidant Defenses of Mycorrhizal Fungus Infection Against SO<Subscript>2</Subscript>-Induced Oxidative Stress in <Emphasis Type="Italic">Avena nuda</Emphasis> Seedlings

Colonization of arbuscular mycorrhizal fungi Glomus mosseae increased Avena nuda seedling tolerance to SO(2) exposure, as indicated by elevated total plant biomass and ameliorative photosynthetic rate, when compared to the non-mycorrhizal plants. This is associated with an improved antioxidant capacity as shown by enhanced superoxide dismutase and catalase activity, increased ascorbic acid and glutathione content, and reduced malondialdehyde and hydrogen peroxide level in the mycorrhizal plants relative to the non-mycorrhizal plants under SO(2) exposure. The mycorrhizal fungi colonization had no effect on the stomatal conductance. To our knowledge, this is the first finding of this sort.     

Model-based estimation of the attributable fraction for cross-sectional,case–control and cohort studies using the <Emphasis FontCategory="NonProportional">R</Emphasis> package <Emphasis FontCategory="NonProportional">AF</Emphasis>

The attributable fraction (or attributable risk) is a widely used measure that quantifies the public health impact of an exposure on an outcome. Even though the theory for AF estimation is well developed, there has been a lack of up-to-date software implementations. The aim of this article is to present a new R package for AF estimation with binary exposures. The package AF allows for confounder-adjusted estimation of the AF for the three major study designs: cross-sectional, (possibly matched) case–control and cohort. The article is divided into theoretical sections and applied sections. In the theoretical sections we describe how the confounder-adjusted AF is estimated for each specific study design. These sections serve as a brief but self-consistent tutorial in AF estimation. In the applied sections we use real data examples to illustrate how the AF package is used. All datasets in these examples are publicly available and included in the AF package, so readers can easily replicate all analyses.     

Effects of Elevated Ozone on Photosynthetic CO<Subscript>2</Subscript> Exchange and Chlorophyll <Emphasis Type="Italic">a</Emphasis> Fluorescence in Leaves of <Emphasis Type="Italic">Quercus mongolica</Emphasis> Grown in Urban Area

The aim of this study was to determine the responses of photosynthesis in leaves of Quercus mongolica to elevated O₃ exposure in an urban area. The results showed that the photosynthesis parameters were all decreased by the elevated O₃ during the whole season. Especially, light-saturated net photosynthetic rate (A) was reduced about 72% after 45 days exposure, and over the whole growing season, the differences were significant (p < 0.05) compared with control. The reduction is related to both stomatal and non-stomatal factors, including a decrease (about 9%) in the maximum quantum yield of PSII photochemistry (F _v/F _m) detected after 90 days O₃ exposure.     

Carbonaceous species and physicochemical characteristics of PM<Subscript>10</Subscript> in coal mine fire area—a case study

When exposed to air, coal catches fire due to self-oxidation. Coal mine fire is one of the major sources of particulate matter (PM) emissions in coal mining areas. Coal mine is widespread in India with Jharia Coalfield having a number of coal seams and coal dumps under fire. The understanding of magnitude and character of particulate matter emitted from coal mine fire areas is important in order to understand its health impacts, about which not many studies have been carried out. The paper presents findings of a study aimed to characterize physical and chemical properties of airborne respirable particle (PM₁₀) in the fire-affected area at Jharia Coalfield, India. The study was carried out for a period of 8 months from October 2011 to June 2012. The mean concentrations of PM₁₀ were 338.0, 369.0, and 357.0 μg m^?3 during summer, winter, and post-monsoon, respectively. Scanning electron microscopy (SEM) showed the presence of rounded, spherical, and oval formed particulate in ambient air that is characteristics of combustion sources. Dominance of irregular-shaped particulate in all samples indicated road dust as the source. Abundance of fine PM (<4 mm) indicated burning process to be the source. For the “qualitative analysis,” techniques like Fourier transform infrared (FTIR) spectroscopy, gas chromatography–mass spectrometry (GC-MS), and inductively coupled plasma optical emission spectrometry (ICP-OES) were used. Chemical analysis shows the presence of elements like Fe, Al, Cu, Si, Na, Cr, Mn, Zn, Cd, Ni, K, and Pb. Anionic concentrations of SO₄ ^2?, NO₃ ^?,Cl^?, F^?, and PO₄ ^2? were analyzed using ion chromatography. Carbonaceous aerosol analysis results indicated that concentrations of carbonaceous species were 19.51 μg m^?3 for organic carbon (OC) and 238.0 μg m^?3 for elemental carbon (EC) in PM₁₀ samples.     

Expanding the concept of parental control: a role for overt and covert control in children's snacking behaviour?

The existing literature on parental control and children's diets is confusing. The present paper reports two studies to explore an expanded conceptualisation of parental control with a focus on overt control which 'can be detected by the child' and covert control which 'cannot be detected by the child'. In study 1, 297 parents of children aged between 4 and 11 completed a measure of overt control and covert control alongside ratings of their child's snacking behaviour as a means to assess who uses either overt or covert control and how these aspects of parental control relate to a child's snacking behaviour. The results showed that lighter parents and those with children perceived as heavier were more likely to use covert control and those from a higher social class were more likely to use overt control. Further, whilst greater covert control predicted a decreased intake of unhealthy snacks, greater overt control predicted an increased intake of healthy snacks. In study 2, 61 parents completed the same measure of overt and covert control alongside the three control subscales of the Child Feeding Questionnaire [Birch, L.L., Fisher, J.O., Grimm-Thomas, Markey, C.N., Sawyer, R. (2001). Confirmatory factor analysis of the Child Feeding Questionnaire: A measure of parental attitudes, beliefs and practices about child feeding and obesity proneness. Appetite, 36, 201-210] to assess degrees of overlap between these measures. The results showed that although these five measures of control were all positively correlated, the correlations between the new and existing measures indicated a maximum of 21% shared variance suggesting that covert and overt control are conceptually and statistically separate from existing measures of control. To conclude, overt and covert control may be a useful expansion of existing ways to measure and conceptualise parental control. Further, these constructs may differentially relate to snacking behaviour which may help to explain some of the confusion in the literature.     

A defect in Δ<Superscript>6</Superscript> and Δ<Superscript>5</Superscript> desaturases may be a factor in the initiation and progression of insulin resistance,the metabolic syndrome and ischemic heart disease in South Asians

The high incidence of insulin resistance and the metabolic syndrome in South Asians remains unexplained. I propose that a defect in the activity of Δ⁶ and Δ⁵ desaturases and consequent low plasma and tissue concentrations of polyunsaturated fatty acids such as γ-linolenic acid (GLA), dihomo-γ-linolenic acid (DGLA), arachidonic acid (AA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and formation of their anti-inflammatory products prostaglandin E₁ (PGE₁), prostacyclin (PGI₂), PGI₃, lipoxins, resolvins, protectins, maresins and nitrolipids could be responsible for the high incidence of insulin resistance, the metabolic syndrome and ischemic heart disease (IHD) in South Asians. This proposal is supported by the observation that South Asian Indians have lower plasma and tissue concentrations of GLA, DGLA, AA, EPA and DHA, the precursors of PGE₁, PGI₂, PGI₃, lipoxins, resolvins, protectins, and nitrolipids, the endogenous molecules that prevent platelet aggregation, vasoconstriction, thrombus formation, leukocyte activation and possess anti-inflammatory action and thus, are capable of preventing the development of insulin resistance, atherosclerosis, hypertension, type 2 diabetes mellitus and premature ischemic heart disease. Genetic predisposition, high carbohydrate intake, lack of exercise, tobacco use and low birth weight due to maternal malnutrition suppress the activity of Δ⁶ and Δ⁵ desaturases that leads to low plasma and tissue concentrations of polyunsaturated fatty acids and their products. This implies that adequate provision of polyunsaturated fatty acids and co-factors needed for their metabolism, and efforts to enhance the formation of their beneficial metabolites PGE₁, PGI₂, PGI₃, lipoxins, resolvins, protectins, maresins and nitrolipids could form a novel approach in the prevention and management of these diseases in this high-risk population.     

Influence of common variants in <Emphasis Type="Italic">FTO</Emphasis> and near <Emphasis Type="Italic">INSIG2</Emphasis> and <Emphasis Type="Italic">MC4R</Emphasis> on growth curves for adiposity in African– and European–American youth

Recent genome-wide association (GWA) studies identified several common variants for obesity: rs9939609 in FTO, rs7566605 near INSIG2 and both rs17782313 and rs17700633 near the MC4R gene. This study aimed to assess the influence of these polymorphisms on development of adiposity in European– (EA) and African–American (AA) youth in two ongoing longitudinal studies including 986 and 606 participants with age ranges of 10–25.8 and 4.0–23.9 years, respectively. Individual growth curve modeling was conducted separately in the two studies. We tested the effect of the SNPs on levels and increase with age (i.e., slope) of weight, body mass index (BMI), waist circumference and skinfolds from childhood to adulthood, and potential moderation by ethnicity or gender. Beta coefficients computed in the two studies were pooled using meta-analysis. Rs9939609 was associated with logtransformed levels of BMI (β = 0.021, P = 0.01), weight (β = 0.019, P = 0.04) and waist circumference (β = 0.012, P = 0.04). Rs17782313 was associated with triceps (β = 0.05, P = 0.02). Significant interactions of rs17700633 with gender were observed on subscapular-, suprailiac- and sum of skinfolds, with significant associations limited to males (P < 0.05). No significant interactions with ethnicity were found. Only one effect on the slope was observed, rs17700633 showed a significant interaction with age on triceps (β = 0.004, P = 0.04). In two longitudinal studies of EA and AA youth, we replicated the effect of FTO and common variants near MC4R on general and central adiposity. These variants did not affect the increase with age of adiposity from childhood to adulthood with one exception. Common variants for obesity identified in GWA studies have detectable but modest effects on growth curves for adiposity in EA and AA youth.