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Urbanization and extreme flows are altering stream temperature dynamics, yet our understanding of the impact of urbanization and extreme flows on stream temperature is limited. We deployed 27 water temperature loggers in three headwater catchments over three summers. We categorized flow as low, high, or average and calculated daily water temperature anomalies. Comparing Z scores between flow conditions revealed the impact of extreme events on water temperature. We used multiple linear regressions to identify landscape predictors of water temperature. We found during low flows stream temperatures were significantly warmer. Additionally, urban landscape predictors were linked to reduced warming during low flows. Our study highlights that low flows increase extreme water temperature events; however, this effect was less pronounced in more urbanized sites. High flows did not significantly affect water temperature anomalies. These results underscore the vulnerability of rivers to extreme temperatures during low flows; however, landscape may help mitigate these effects. [ABSTRACT FROM AUTHOR]

Introduction/Aims: Muscle weakness, and its association with mobility limitations, has received little study in oculopharyngeal muscular dystrophy (OPMD) using quantitative and standardized assessments. The objectives of this study were to (1) document upper and lower limb muscle strength, upper limb functions, fatigue, and mobility capacities; (2) compare them with reference values and across participant age groups; and (3) explore associations between muscle strength, fatigue, and mobility capacities among adults with OPMD. Methods: Thirty‐four participants were included in this cross‐sectional study. The following variables were assessed: quantitative maximal isometric muscle strength, grip and pinch strength, fatigue, walking speed, walking endurance, sit‐to‐stand, and stair ascent and descent capacities. Results: Muscle strength was lower for older than younger participants for five muscle groups (P <.05). Walking endurance, sit‐to‐stand, stairs (ascent and descent), and strength of hip flexion, grip, and pinch were below 80% of reference values in participants ≥56 y old (55.3%–78.2%). Moderate to strong correlations were found between muscle strength and mobility capacities (ρ = 0.42–0.80, P <.05), and between fatigue and either muscle strength or mobility capacities (ρ = 0.42–0.75, P <.05). Discussion: This study highlights the impact of OPMD on strength, endurance, and functional capacity, among others, with patients being well below reference values even before the age of 65 y. In addition to helping health professionals to offer better clinical guidance, these results will improve clinical trial readiness. The next steps will be to assess the metrological properties of outcome measures and continue to document the disease progression rate. [ABSTRACT FROM AUTHOR]

Increasing awareness of the complexity of river ecosystems has led to the emergence of integrative disciplines that combine topics in river physical and ecological processes, exemplified by the disciplines of ecohydrology, hydroecology and ecohydraulics. However, the names of these disciplines are often referred to interchangeably without attention paid to their meaning. This ambiguity impairs the efficient development and widespread promotion of these fields of study and their applications. To address this issue, we strive to clarify the definitions and contributions of the different disciplines. This is done by exploring their interrelationships and providing a reference for the integration of disciplines in these evolving fields. Finally, we advocate for ecohydrology and ecohydraulics to be considered complementary, and not duplicative, disciplines within river science. We further argue that awareness of their similarities and differences is important to address key issues in river science and to ensure ecohydraulics finds its positioning with respect to other disciplines, as well as current and emerging societal and scientific challenges, such as climate change. [ABSTRACT FROM AUTHOR]

Aims Calcific aortic valve disease (CAVD) is characterized by the osteogenic transition of valve interstitial cells (VICs). In CAVD, lysophosphatidic acid (LysoPA), a lipid mediator with potent osteogenic activity, is produced in the aortic valve (AV) and is degraded by membrane-associated phospholipid phosphatases (PLPPs). We thus hypothesized that a dysregulation of PLPPs could participate to the osteogenic reprograming of VICs during CAVD. Methods and results The expression of PLPPs was examined in human control and mineralized AVs and comprehensive analyses were performed to document the gene regulation and impact of PLPPs on the osteogenic transition of VICs. We found that PLPP3 gene and enzymatic activity were downregulated in mineralized AVs. Multidimensional gene profiling in 21 human AVs showed that expression of PLPP3 was inversely correlated with the level of 5-methylcytosine (5meC) located in an intronic mammalian interspersed repeat (MIR) element. Bisulphite pyrosequencing in a larger series of 67 AVs confirmed that 5meC in intron 1 was increased by 2.2-fold in CAVD compared with control AVs. In isolated cells, epigenome editing with clustered regularly interspersed short palindromic repeats-Cas9 system containing a deficient Cas9 fused with DNA methyltransferase (dCas9-DNMT) was used to increase 5meC in the intronic enhancer and showed that it reduced significantly the expression of PLPP3. Knockdown experiments showed that lower expression of PLPP3 in VICs promotes an osteogenic programme. Conclusions DNA methylation of a MIR-based enhancer downregulates the expression of PLPP3 and promotes the mineralization of the AV. [ABSTRACT FROM AUTHOR]

Background: Children exposed to gestational diabetes mellitus (GDM) are at a higher risk of developing obesity and type 2 diabetes. This susceptibility might involve brown adipose tissue (BAT), which is suspected to protect against obesity. The objective of this study is to assess whether fetal exposure to maternal hyperglycemia is associated with DNA methylation variations in genes involved in BAT genesis and activation. Methods: DNA methylation levels at the PRDM16, BMP7, CTBP2, and PPARGC1α gene loci were measured in placenta samples using bisulfite pyrosequencing in E-21 (n = 133; 33 cases of GDM) and the HumanMethylation450 array in Gen3G (n = 172, all from non-diabetic women) birth cohorts. Glucose tolerance was assessed in all women using an oral glucose tolerance test at the second trimester of pregnancy. Participating women were extensively phenotyped throughout pregnancy, and placenta and cord blood samples were collected at birth. Results: We report that maternal glycemia at the second and third trimester of pregnancy are correlated with variations in DNA methylation levels at PRDM16, BMP7, and PPARGC1α and with cord blood leptin levels. Variations in PRDM16 and PPARGC1α DNA methylation levels were also correlated with cord blood leptin levels. Mediation analyses support that DNA methylation variations at the PPARGC1α gene locus explain 0.8% of the cord blood leptin levels variance independently of maternal fasting glucose levels (p = 0.05). Conclusions: These results suggest that maternal glucose in pregnancy could produce variations in DNA methylation in BAT-related genes and that some of these DNA methylation marks seem to mediate the impact of maternal glycemia on cord blood leptin levels, an adipokine regulating body weight. [ABSTRACT FROM AUTHOR]

Background Two asthma-associated regions 17q12- q21 and 5q31.1 harbour genes that show strong effect of genotype on expression levels. DNA methylation has an important role in gene regulation; therefore, we examined DNA methylation at promoters of 12 genes from 5q31 and 17q12-q21 regions. Our goal was to determine whether DNA methylation was associated with predisposition to asthma and whether such a relationship was independent from genetic association. Methods Using sodium bisulfite sequencing and pyrosequencing methylation assays, we examined the effect of genotype on DNA methylation in peripheral blood cells from individuals from the Saguenay-Lac-Saint- Jean asthma familial collection and lymphoblastoid cell lines. Results The local genotype influenced methylation levels of solute carrier family 22 (organic 3 cation/ carnitine transporter) member 5 (SLC22A5), zona pellucida binding protein 2 (ZPBP2) and gasdermin A GSDMA) promoter regions. The genotype had a dominant effect on ZPBP2 and GSDMA methylation with lower methylation levels in individuals that carry the asthma-predisposing alleles. Males also had lower methylation at the ZPBP2 promoter than females. We did not observe an effect of asthma status that would be independent of the genotype and the sex effects in the GSDMA, ZPBP2 and SLC22A5 regions; however, GSDMA and ZPBP2 data were suggestive of interaction between asthma and methylation levels in females and SLC22A5 in males. Conclusions The local genotype influences methylation levels at SLC22A5 and ZPBP2 promoters independently of the asthma status. Further studies are necessary to confirm the relationship between GSDMA-ZPBP2 and SLC22A5 methylation and asthma in females and males separately. [ABSTRACT FROM AUTHOR]

Interleukin 1 and its receptors are associated with allergic diseases such as asthma. In the present study, we measured DNA methylation at the IL1R1 and IL1R2 gene loci and assessed for associations with asthma-related phenotypes and gene expressions. We found that asthmatic and atopic individuals have higher IL1R2 promoter DNA methylation than control subjects. Additionally, we observed a negative correlation between DNA methylation at the IL1R2 promoter and IL1R2 mRNA expression. These results suggest for the first time that IL1R2 promoter DNA methylation is associated with its gene repression in allergic diseases such as asthma. [ABSTRACT FROM AUTHOR]

One of the challenges when modelling a complex variable such as water temperature in rivers is that it can be difficult to determine the sources of error and to ensure that the simulations are truly representative of the reality. Therefore, a heat budget study was completed in a controlled environment, which excluded advection and bottom fluxes but enabled observation of all the other fluxes. A 21.42 m3 pool was installed and insulated to limit heat exchange through the sides and bottom. All the major energy fluxes were monitored for a 50-day period. Different equations for individual heat budget terms were tested to determine their ability to reproduce the observations. This experiment also permitted to assess the relative importance of each component of the heat budget. Performance of each semi-empirical equation was determined by comparing predictions and measured values. It was thus possible to choose the formulae that best represented the measured heat exchange processes, while understanding the limits of some of the semi-empirical representations of heat exchange processes. The results highlight the importance of radiative terms into the heat budget because they controlled the major sources and sinks. The study also showed the importance of the wind function determination into the calculation of latent heat flux. The resulting water temperature model returned simulated hourly water temperature with an overall root mean square error of 0.71 °C/h and a modified Nash-Sutcliffe coefficient of 0.97. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

During the summer of 2001, the largest fish kill in the recorded history of the St. Lawrence River occurred. More than 25,000 dead carp were recovered. Preliminary analyses suggested hydroclimatic factors may have triggered the fish kill. Long time series of hydroclimatic variables were available upstream and downstream from the study area. In order to investigate if hydroclimatic conditions were extreme during the summer of 2001, frequency analyses were performed on time series of air and water temperature, water level, and solar radiation. During this period, the daily maximum water temperature was abnormally high (return period of 47 years) relative to other years. Air temperature was also high (return period of 22 years) and water level was very low (return period of 67 years). Results showed that hydroclimatic forcings were acting at two different time scales. First, short-term extremes are more likely to have direct impacts on ecosystems, such as lethal stress caused by oxygen depletion in shallow areas. Long-term extremes have indirect effects, which are more difficult to detect, such as immunosuppression. These results reiterate the importance of water temperature in aquatic habitat, particularly in the present context of global warming and climate change. [ABSTRACT FROM AUTHOR]

The aim of this study was to identify placental DNA methylation (DNAm) variations associated with adiposity at 3 years of age. We quantified placental DNAm using the Infinium MethylationEPIC BeadChips. We assessed associations between DNAm at single-CpGs and skinfold thickness using robust linear regression models adjusted for gestational age, child's sex, age at follow-up and cellular heterogeneity. We sought replication of DNAm association with child adiposity in an independent cohort. We quantified placental mRNA levels for annotated gene using qRT-PCR and tested for correlation with DNAm. Lower DNAm at cg22593959 and cg22436429 was associated with higher adiposity (β = −1.18, q = 0.002 and β = −0.82, q = 0.04). The cg22593959 is located in an intergenic region (chr7q31.3), whereas cg22436429 is within the TFAP2E gene (1p34.3). DNAm at cg22593959 and cg22436429 was correlated with mRNA levels at FAM3C (rs = −0.279, p = 0.005) and TFAP2E (rs = 0.216, p = 0.03). In an independent cohort, the association between placental DNAm at cg22593959 and childhood adiposity was of similar strength and direction (β = −3.8 ± 4.1, p = 0.36), yet non-significant. Four genomic regions were also associated with skinfold thickness within FMN1, MAGI2, SKAP2 and BMPR1B genes. We identified placental epigenetic variations associated with adiposity at 3 years of age suggesting that childhood fat accretion patterns might be established during fetal life. [ABSTRACT FROM AUTHOR]

Changes in fetal DNA methylation (DNAm) of the leptin (LEP) gene have been associated with exposure to maternal hyperglycemia, but their links with childhood obesity risk are still unclear. We investigated the association between maternal hyperglycemia, placental LEP DNAm (25 5′-C-phosphate-G-3′ (CpG) sites), neonatal leptinemia, and adiposity (i.e., BMI and skinfold thickness (ST) (subscapular (SS) + triceps (TR) skinfold measures, and the ratio of SS:TR) at 3-years-old, in 259 mother–child dyads, from Gen3G birth cohort. We conducted multivariate linear analyses adjusted for gestational age at birth, sex of the child, age at follow-up, and cellular heterogeneity. We assessed the causal role of DNAm in the association between maternal glycemia and childhood outcomes, using mediation analysis. We found three CpGs associated with neonatal leptinemia (p ≤ 0.002). Of these, cg05136031 and cg15758240 were also associated with BMI (β = −2.69, p = 0.05) and fat distribution (β = −0.581, p = 0.05) at 3-years-old, respectively. Maternal glycemia was associated with DNAm at cg15758240 (β = −0.01, p = 0.04) and neonatal leptinemia (β = 0.19, p = 0.004). DNAm levels at cg15758240 mediates 0.8% of the association between maternal glycemia and neonatal leptinemia (p < 0.001). Our results support that DNAm regulation of the leptin pathway in response to maternal glycemia might be involved in programming adiposity in childhood. [ABSTRACT FROM AUTHOR]

A previous genome-wide linkage scan of bronchial hyperresponsiveness (BHR) in the French Epidemiological study on the Genetics and Environment of Asthma (EGEA) families, performed in the presence of a gene×early-life environmental tobacco smoke (ETS) exposure interaction, showed the strongest interaction in the 17p11 region where linkage was detected only among unexposed siblings. Our goal was to conduct fine-scale mapping of 17p11 to identify single nucleotide polymorphisms (SNPs) interacting with ETS that influence BHR.Analyses were performed in 388 French EGEA asthmatic families, using a two-step strategy: 1) selection of SNPs displaying family-based association test (FBAT) association signals (p≤0.01) with BHR in unexposed siblings, and 2) a FBAT homogeneity test between exposed and unexposed siblings plus a robust log-linear interaction test.A single SNP reached the threshold (p≤3×10(-3)) for significant interaction with ETS using both interaction tests, after accounting for multiple testing. Results were replicated in 253 French-Canadian families, but not in 341 UK families, probably due in part to differences in phenotypic features between datasets.The SNP showing significant interaction with ETS belongs toDNAH9(dynein, axonemal, heavy chain 9), a promising candidate gene involved in respiratory cilia mobility and associated with primary ciliary dyskinesia, a disease associated with abnormalities of pulmonary function., (Copyright ©ERS 2016.)