Epigenome-wide analysis links SMAD3 methylation at birth to asthma in children of asthmatic mothers

Background The timing and mechanisms of asthma inception remain imprecisely defined. Although epigenetic mechanisms likely contribute to asthma pathogenesis, little is known about their role in asthma inception. Objective We sought to assess whether the trajectory to asthma begins already at birth and whether epigenetic mechanisms, specifically DNA methylation, contribute to asthma inception. Methods We used the Methylated CpG Island Recovery Assay chip to survey DNA methylation in cord blood mononuclear cells from 36 children (18 nonasthmatic and 18 asthmatic subjects by age 9 years) from the Infant Immune Study (IIS), an unselected birth cohort closely monitored for asthma for a decade. SMAD3 methylation in IIS (n = 60) and in 2 replication cohorts (the Manchester Asthma and Allergy Study [n = 30] and the Childhood Origins of Asthma Study [n = 28]) was analyzed by using bisulfite sequencing or Illumina 450K arrays. Cord blood mononuclear cell–derived IL-1β levels were measured by means of ELISA. Results Neonatal immune cells harbored 589 differentially methylated regions that distinguished IIS children who did and did not have asthma by age 9 years. In all 3 cohorts methylation in SMAD3, the most connected node within the network of asthma-associated, differentially methylated regions, was selectively increased in asthmatic children of asthmatic mothers and was associated with childhood asthma risk. Moreover, SMAD3 methylation in IIS neonates with maternal asthma was strongly and positively associated with neonatal production of IL-1β, an innate inflammatory mediator. Conclusions The trajectory to childhood asthma begins at birth and involves epigenetic modifications in immunoregulatory and proinflammatory pathways. Maternal asthma influences epigenetic mechanisms that contribute to the inception of this trajectory

The Fatty Liver Index: a simple and accurate predictor of hepatic steatosis in the general population

BACKGROUND: Fatty liver (FL) is the most frequent liver disease in Western countries. We used data from the Dionysos Nutrition & Liver Study to develop a simple algorithm for the prediction of FL in the general population. METHODS: 216 subjects with and 280 without suspected liver disease were studied. FL was diagnosed by ultrasonography and alcohol intake was assessed using a 7-day diary. Bootstrapped stepwise logistic regression was used to identify potential predictors of FL among 13 variables of interest [gender, age, ethanol intake, alanine transaminase, aspartate transaminase, gamma-glutamyl-transferase (GGT), body mass index (BMI), waist circumference, sum of 4 skinfolds, glucose, insulin, triglycerides, and cholesterol]. Potential predictors were entered into stepwise logistic regression models with the aim of obtaining the most simple and accurate algorithm for the prediction of FL. RESULTS: An algorithm based on BMI, waist circumference, triglycerides and GGT had an accuracy of 0.84 (95%CI 0.81–0.87) in detecting FL. We used this algorithm to develop the "fatty liver index" (FLI), which varies between 0 and 100. A FLI < 30 (negative likelihood ratio = 0.2) rules out and a FLI ≥ 60 (positive likelihood ratio = 4.3) rules in fatty liver. CONCLUSION: FLI is simple to obtain and may help physicians select subjects for liver ultrasonography and intensified lifestyle counseling, and researchers to select patients for epidemiologic studies. Validation of FLI in external populations is needed before it can be employed for these purposes

Early growth patterns and cardiometabolic function at the age of 5 in a multiethnic birth cohort: the ABCD study

<p>Abstract</p> <p>Background</p> <p>The relation between fetal growth retardation and cardiovascular and metabolic diseases in later life has been demonstrated in many studies. However, debate exists around the potential independent role of postnatal growth acceleration. Furthermore, it is unknown whether a potential effect of growth acceleration on cardiovascular and metabolic function is confined to certain timeframes.</p> <p>The present study assesses the (predictive) role of prenatal and postnatal growth on 5 components of cardiovascular and metabolic function in children aged 5. The potential association of timing of postnatal growth acceleration with these outcomes will be explored.</p> <p>Methods and design</p> <p>Prospective multiethnic community-based cohort study of 8266 pregnancies (Amsterdam Born Children and their Development, ABCD study). Up till now, anthropometry of 5104 children from the original cohort was followed during the first 5 years of life, with additional information about birth weight, pregnancy duration, and various potential confounding variables.</p> <p>At age 5, various components of cardiovascular and metabolic function are being measured. Outcome variables are body size, body composition and fat distribution, insulin sensitivity, lipid profile, blood pressure and autonomic regulation of cardiovascular function.</p> <p>Discussion</p> <p>This study will be one of the first population-based prospective cohort studies to address the association between measures of both prenatal and postnatal growth and various components of cardiovascular and metabolic function. Specific attention is paid to the timing of acceleration in growth and its potential association with the outcome variables. Importantly, the longitudinal design of this study gives us the opportunity to gain more insight into growth trajectories associated with adverse outcomes in later life. If identified as an independent risk factor, this provides further basis for the hypothesis that accelerated growth during the first years of life is a modifiable factor for the prevention of cardiovascular and metabolic disorders in later life. Moreover, identification of specific vulnerable periods during development may reveal suitable timeframes for early interventions.</p

Cardio-metabolic risk in 5-year-old children prenatally exposed to maternal psychosocial stress: the ABCD study

<p>Abstract</p> <p>Background</p> <p>Recent evidence, both animal and human, suggests that modifiable factors during fetal and infant development predispose for cardiovascular disease in adult life and that they may become possible future targets for prevention. One of these factors is maternal psychosocial stress, but so far, few prospective studies have been able to investigate the longer-term effects of stress in detail, i.e. effects in childhood. Therefore, our general aim is to study whether prenatal maternal psychosocial stress is associated with an adverse cardio-metabolic risk profile in the child at age five.</p> <p>Methods/design</p> <p>Data are available from the Amsterdam Born Children and their Development (ABCD) study, a prospective birth cohort in the Netherlands. Between 2003-2004, 8,266 pregnant women filled out a questionnaire including instruments to determine anxiety (STAI), pregnancy related anxiety (PRAQ), depressive symptoms (CES-D), parenting stress (PDH scale) and work stress (Job Content Questionnaire).</p> <p>Outcome measures in the offspring (age 5-7) are currently collected. These include lipid profile, blood glucose, insulin sensitivity, body composition (body mass index, waist circumference and bioelectrical impedance analysis), autonomic nervous system activity (parasympathetic and sympathetic measures) and blood pressure.</p> <p>Potential mediators are maternal serum cortisol, gestational age and birth weight for gestational age (intrauterine growth restriction). Possible gender differences in programming are also studied.</p> <p>Discussion</p> <p>Main strengths of the proposed study are the longitudinal measurements during three important periods (pregnancy, infancy and childhood), the extensive measurement of maternal psychosocial stress with validated questionnaires and the thorough measurement of the children's cardio-metabolic profile. The availability of several confounding factors will give us the opportunity to quantify the independent contribution of maternal stress during pregnancy to the cardio-metabolic risk profile of her offspring. Moreover, the mediating role of maternal cortisol, intrauterine growth, gestational age and potential gender differences can be explored extensively. If prenatal psychosocial stress is indeed found to be associated with the offspring's cardio-metabolic risk, these results support the statement that primary prevention of cardiovascular disease may start even before birth by reducing maternal stress during pregnancy.</p

Maintenance of Large Subpopulations of Differentiated CD8 T-Cells Two Years after Cytomegalovirus Infection in Gambian Infants

BACKGROUND: In a previously published study, we found that large differentiated subpopulations of CD8 T-cells emerged rapidly after CMV infection in young infants and persisted throughout the following year. Here we describe a follow-up study conducted on the same infants to establish whether the differentiated subpopulations continued through the second year post-infection. METHODOLOGY / PRINCIPAL FINDINGS: CMV-specific cells identified using tetramers remained more activated and differentiated than the overall CD8 population. The large subpopulation of differentiated cytotoxic (CD28(-)CD62L(-)Bcl-2(low)CD95(+)perforin(+)) cells that emerged rapidly after infection remained stable after two years. No similar subpopulation was found in CMV-uninfected infants indicating that two years after infection, CMV remained a major factor in driving CD8 T-cell differentiation. Although markers of activation (CD45R0 and HLA-D) declined throughout the first year, HLA-D expression continued to decline during the second year and CD45R0 expression increased slightly. The age-related increase in IFNgamma response observed during the first year continued but was non-significant during the second year, indicating that the rate of functional improvement had slowed substantially. CONCLUSIONS / SIGNIFICANCE: The large differentiated subpopulations of CD8 T-cells that had emerged immediately after CMV infection persisted through the second year post-infection, while levels of activation and functional capacity remained fairly constant.Journal ArticleResearch Support, Non-U.S. Gov'tSCOPUS: ar.jinfo:eu-repo/semantics/publishe

HFE Gene Variants Modify the Association between Maternal Lead Burden and Infant Birthweight: A Prospective Birth Cohort Study in Mexico City, Mexico

<p>Abstract</p> <p>Background</p> <p>Neonatal growth is a complex process involving genetic and environmental factors. Polymorphisms in the hemochromatosis (<it>HFE</it>) iron regulatory genes have been shown to modify transport and toxicity of lead which is known to affect birth weight.</p> <p>Methods</p> <p>We investigated the role of <it>HFE C282Y</it>, <it>HFE H63 D</it>, and transferrin <it>(TF) P570 S </it>gene variants in modifying the association of lead and infant birthweight in a cohort of Mexican mother-infant pairs. Subjects were initially recruited between 1994-1995 from three maternity hospitals in Mexico City and 411 infants/565 mothers had archived blood available for genotyping. Multiple linear regression models, stratified by either maternal/infant <it>HFE </it>or <it>TF </it>genotype and then combined with interaction terms, were constructed examining the association of lead and birthweight after controlling for covariates.</p> <p>Results</p> <p>3.1%, 16.8% and 17.5% of infants (N = 390) and 1.9%, 14.5% and 18.9% of mothers (N = 533) carried the <it>HFE C282Y</it>, <it>HFE H63D</it>, and <it>TF P570 S </it>variants, respectively. The presence of infant <it>HFE H63 D </it>variants predicted 110.3 g (95% CI -216.1, -4.6) decreases in birthweight while maternal <it>HFE H63 D </it>variants predicted reductions of 52.0 g (95% CI -147.3 to 43.2). Interaction models suggest that both maternal and infant <it>HFE H63 D </it>genotype may modify tibia lead's effect on infant birthweight in opposing ways. In our interaction models, maternal <it>HFE H63 D </it>variant carriers had a negative association between tibia lead and birthweight.</p> <p>Conclusions</p> <p>These results suggest that the <it>HFE H63 D </it>genotype modifies lead's effects on infant birthweight in a complex fashion that may reflect maternal-fetal interactions with respect to the metabolism and transport of metals.</p

Historical biogeography of the leopard (Panthera pardus) and its extinct Eurasian populations

Background: Resolving the historical biogeography of the leopard (Panthera pardus) is a complex issue, because patterns inferred from fossils and from molecular data lack congruence. Fossil evidence supports an African origin, and suggests that leopards were already present in Eurasia during the Early Pleistocene. Analysis of DNA sequences however, suggests a more recent, Middle Pleistocene shared ancestry of Asian and African leopards. These contrasting patterns led researchers to propose a two-stage hypothesis of leopard dispersal out of Africa: an initial Early Pleistocene colonisation of Asia and a subsequent replacement by a second colonisation wave during the Middle Pleistocene. The status of Late Pleistocene European leopards within this scenario is unclear: were these populations remnants of the first dispersal, or do the last surviving European leopards share more recent ancestry with their African counterparts? Results: In this study, we generate and analyse mitogenome sequences from historical samples that span the entire modern leopard distribution, as well as from Late Pleistocene remains. We find a deep bifurcation between African and Eurasian mitochondrial lineages (~ 710 Ka), with the European ancient samples as sister to all Asian lineages (~ 483 Ka). The modern and historical mainland Asian lineages share a relatively recent common ancestor (~ 122 Ka), and we find one Javan sample nested within these. Conclusions: The phylogenetic placement of the ancient European leopard as sister group to Asian leopards suggests that these populations originate from the same out-of-Africa dispersal which founded the Asian lineages. The coalescence time found for the mitochondrial lineages aligns well with the earliest undisputed fossils in Eurasia, and thus encourages a re-evaluation of the identification of the much older putative leopard fossils from the region. The relatively recent ancestry of all mainland Asian leopard lineages suggests that these populations underwent a severe population bottleneck during the Pleistocene. Finally, although only based on a single sample, the unexpected phylogenetic placement of the Javan leopard could be interpreted as evidence for exchange of mitochondrial lineages between Java and mainland Asia, calling for further investigation into the evolutionary history of this subspecies

Engagement Across Developmental Periods

The goal of this chapter is to provide a cohesive developmental framework and foundation for which to understand student engagement across early childhood, middle childhood, and adolescence. Guided by the bioecological theory of human development and the person-environment fit perspective, this chapter extends Finn\u27s participation-identification model of engagement by mapping student engagement within a larger developmental sequence. This chapter discusses student engagement within specific developmental periods that are tied to the developmental tasks, opportunities, and challenges unique to early childhood, middle childhood, and adolescence. Student engagement is found to be a nuanced developmental outcome, and the differences may be a result of the maturation of biological, cognitive, and socioemotional developmental tasks and the changing contextual landscape for the children and adolescents. Recommendations for future research as well as policy implications are also discussed