820 research outputs found
Placental PHLDA2 expression is increased in cases of fetal growth restriction following reduced fetal movements
Background
Maternal perception of reduced fetal movements (RFM) is associated with increased risk of fetal growth restriction (FGR) and stillbirth, mediated by placental insufficiency. The maternally expressed imprinted gene PHLDA2 controls fetal growth, placental development and placental lactogen production in a mouse model. A number of studies have also demonstrated abnormally elevated placental PHLDA2 expression in human growth restricted pregnancies. This study examined whether PHLDA2 was aberrantly expressed in placentas of RFM pregnancies resulting in delivery of an FGR infant and explored a possible relationship between PHLDA2 expression and placental lactogen release from the human placenta.
Methods
Villous trophoblast samples were obtained from a cohort of women reporting RFM (N = 109) and PHLDA2 gene expression analysed. hPL levels were assayed in the maternal serum (N = 74).
Results
Placental PHLDA2 expression was significantly 2.3 fold higher in RFM pregnancies resulting in delivery of an infant with FGR (p < 0.01), with highest levels of PHLDA2 expression in the most severe cases. Placental PHLDA2 expression was associated with maternal serum hPL levels (r = −0.30, p = 0.008, n = 74) although this failed to reach statistical significance in multiple linear regression analysis controlling for birth weight (p = 0.07).
Conclusions
These results further highlight a role for placental PHLDA2 in poor perinatal outcomes, specifically FGR associated with RFM. Furthermore, this study suggests a potential relationship between placental PHLDA2 expression and hPL production by the placenta, an association that requires further investigation in a larger cohort
Effectiveness of a School-Based Physical Activity Intervention on Cognitive Performance in Danish Adolescents: LCoMotion-Learning, Cognition and Motion:A Cluster Randomized Controlled Trial
BACKGROUND:Physical activity is associated not only with health-related parameters, but also with cognitive and academic performance. However, no large scale school-based physical activity interventions have investigated effects on cognitive performance in adolescents. The aim of this study was to describe the effectiveness of a school-based physical activity intervention in enhancing cognitive performance in 12-14 years old adolescents. METHODS:A 20 week cluster randomized controlled trial was conducted including seven intervention and seven control schools. A total of 632 students (mean (SD) age: 12.9 (0.6) years) completed the trial with baseline and follow-up data on primary or secondary outcomes (74% of randomized subjects). The intervention targeted physical activity during academic subjects, recess, school transportation and leisure-time. Cognitive performance was assessed using an executive functions test of inhibition (flanker task) with the primary outcomes being accuracy and reaction time on congruent and incongruent trials. Secondary outcomes included mathematics performance, physical activity levels, body-mass index, waist-circumference and cardiorespiratory fitness. RESULTS:No significant difference in change, comparing the intervention group to the control group, was observed on the primary outcomes (p's>0.05) or mathematics skills (p>0.05). An intervention effect was found for cardiorespiratory fitness in girls (21 meters (95% CI: 4.4-38.6) and body-mass index in boys (-0.22 kg/m2 (95% CI: -0.39-0.05). Contrary to our predictions, a significantly larger change in interference control for reaction time was found in favor of the control group (5.0 milliseconds (95% CI: 0-9). Baseline to mid-intervention changes in physical activity levels did not differ significantly between groups (all p's>0.05). CONCLUSIONS:No evidence was found for effectiveness of a 20-week multi-faceted school-based physical activity intervention for enhancing executive functioning or mathematics skills compared to a control group, but low implementation fidelity precludes interpretation of the causal relationship. TRIAL REGISTRATION:www.ClinicalTrials.gov NCT02012881
Neurodevelopmental consequences in offspring of mothers with preeclampsia during pregnancy: underlying biological mechanism via imprinting genes
Purpose
Preeclampsia is known to be a leading cause of mortality and morbidity among mothers and their infants. Approximately 3–8% of all pregnancies in the US are complicated by preeclampsia and another 5–7% by hypertensive symptoms. However, less is known about its long-term influence on infant neurobehavioral development. The current review attempts to demonstrate new evidence for imprinting gene dysregulation caused by hypertension, which may explain the link between maternal preeclampsia and neurocognitive dysregulation in offspring.
Method
Pub Med and Web of Science databases were searched using the terms “preeclampsia,” “gestational hypertension,” “imprinting genes,” “imprinting dysregulation,” and “epigenetic modification,” in order to review the evidence demonstrating associations between preeclampsia and suboptimal child neurodevelopment, and suggest dysregulation of placental genomic imprinting as a potential underlying mechanism.
Results
The high mortality and morbidity among mothers and fetuses due to preeclampsia is well known, but there is little research on the long-term biological consequences of preeclampsia and resulting hypoxia on the fetal/child neurodevelopment. In the past decade, accumulating evidence from studies that transcend disciplinary boundaries have begun to show that imprinted genes expressed in the placenta might hold clues for a link between preeclampsia and impaired cognitive neurodevelopment. A sudden onset of maternal hypertension detected by the placenta may result in misguided biological programming of the fetus via changes in the epigenome, resulting in suboptimal infant development.
Conclusion
Furthering our understanding of the molecular and cellular mechanisms through which neurodevelopmental trajectories of the fetus/infant are affected by preeclampsia and hypertension will represent an important first step toward preventing adverse neurodevelopment in infants
Associations between objectively measured physical activity levels and executive functions in Danish 12-14 year old adolescents - baseline findings from the Learning, Cognition and Motion (LCoMotion) cluster-randomized controlled trial
Intervention effects on dietary intake among children by maternal education level: results of the Copenhagen School Child Intervention Study (CoSCIS)
Dietary intake among Danish children, in general, does not comply with the official recommendations. The objectives of the present study were to evaluate the 3-year effect of a multi-component school-based intervention on nutrient intake in children, and to examine whether an intervention effect depended on maternal education level. A total of 307 children (intervention group: n 184; comparison group: n 123) were included in the present study. All had information on dietary intake pre- and post-intervention (mean age 6·8 and 9·5 years for intervention and comparison groups, respectively) assessed by a 7-d food record. Analyses were conducted based on the daily intake of macronutrients (energy percentage (E%)), fatty acids (E%), added sugar (E%) and dietary fibre (g/d and g/MJ). Analyses were stratified by maternal education level into three categories. Changes in nutrient intake were observed in the intervention group, mainly among children of mothers with a short education ( < 10 years). Here, intake of dietary fibre increased (β = 2·1 g/d, 95 % CI 0·5, 3·6, P= 0·01). Intake of protein tended to increase (β = 0·6 E%, 95 % CI − 0·01, 1·2, P= 0·05), while intake of fat (β = − 1·7 E%, 95 % CI − 3·8, 0·3, P= 0·09) and SFA (β = − 0·9, 95 % CI − 2·0, 0·2, P= 0·10) tended to decrease. Also, a significant intervention effect was observed on the intake of SFA among children of mothers with a long education (β = − 0·8, 95 % CI − 1·5, − 0·03, P= 0·04). This multi-component school-based intervention resulted in changes in the dietary intake, particularly among children of mothers with a short education. As the dietary intake of this subgroup generally differs most from the recommendations, the results of the present study are particularly encouraging
Associations between objectively measured physical activity levels and executive functions in Danish 12-14 year old adolescents - baseline findings from the Learning, Cognition and Motion (LCoMotion) cluster-randomized controlled trial
Search for heavy lepton resonances decaying to a boson and a lepton in collisions at TeV with the ATLAS detector
A search for heavy leptons decaying to a boson and an electron or a muon is presented. The search is based on collision data taken at TeV by the ATLAS experiment at the CERN Large Hadron Collider, corresponding to an integrated luminosity of 20.3 fb, Three high-transverse-momentum electrons or muons are selected, with two of them required to be consistent with originating from a boson decay. No significant excess above Standard Model background predictions is observed, and 95% confidence level limits on the production cross section of high-mass trilepton resonances are derived. The results are interpreted in the context of vector-like lepton and type-III seesaw models. For the vector-like lepton model, most heavy lepton mass values in the range 114-176 GeV are excluded. For the type-III seesaw model, most mass values in the range 100-468 GeV are excluded
Measurement of the muon reconstruction performance of the ATLAS detector using 2011 and 2012 LHC proton–proton collision data
This paper presents the performance of the ATLAS muon reconstruction during the LHC run with pp collisions at √s = 7–8 TeV in 2011–2012, focusing mainly on data collected in 2012. Measurements of the reconstruction efficiency and of the momentum scale and resolution, based on large reference samples of J/ψ → μμ, Z → μμ and ϒ → μμ decays, are presented and compared to Monte Carlo simulations. Corrections to the simulation, to be used in physics analysis, are provided. Over most of the covered phase space (muon |η| < 2.7 and 5 ≲pT ≲pT 100 GeV) the efficiency is above 99% and is measured with per-mille precision. The momentum resolution ranges from 1.7% at central rapidity and for transverse momentum pT ≃ 10 GeV, to 4% at large rapidity and pT ≃ 100 GeV. The momentum scale is known with an uncertainty of 0.05% to 0.2% depending on rapidity. A method for the recovery of final state radiation from the muons is also presented
Search for dark matter in events with heavy quarks and missing transverse momentum in collisions with the ATLAS detector
This article reports on a search for dark matter pair production in association with bottom or top quarks in of collisions collected at TeV by the ATLAS detector at the LHC. Events with large missing transverse momentum are selected when produced in association with high-momentum jets of which one or more are identified as jets containing -quarks. Final states with top quarks are selected by requiring a high jet multiplicity and in some cases a single lepton. The data are found to be consistent with the Standard Model expectations and limits are set on the mass scale of effective field theories that describe scalar and tensor interactions between dark matter and Standard Model particles. Limits on the dark-matter--nucleon cross-section for spin-independent and spin-dependent interactions are also provided. These limits are particularly strong for low-mass dark matter. Using a simplified model, constraints are set on the mass of dark matter and of a coloured mediator suitable to explain a possible signal of annihilating dark matter
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