Université de Sherbrooke

About: Université de Sherbrooke is a education organization based out in Sherbrooke, Quebec, Canada. It is known for research contribution in the topics: Population & Receptor. The organization has 14922 authors who have published 28783 publications receiving 792511 citations. The organization is also known as: Universite de Sherbrooke & Sherbrooke University.

Protective Effects of GLP-1 on Glomerular Endothelium and Its Inhibition by PKCβ Activation in Diabetes

Abstract: To characterize glucagon-like peptide (GLP)-1 signaling and its effect on renal endothelial dysfunction and glomerulopathy. We studied the expression and signaling of GLP-1 receptor (GLP-1R) on glomerular endothelial cells and the novel finding of protein kinase A–dependent phosphorylation of c-Raf at Ser259 and its inhibition of angiotensin II (Ang II) phospho–c-Raf(Ser338) and Erk1/2 phosphorylation. Mice overexpressing protein kinase C (PKC)β2 in endothelial cells (EC-PKCβ2Tg) were established. Ang II and GLP-1 actions in glomerular endothelial cells were analyzed with small interfering RNA of GLP-1R. PKCβ isoform activation induced by diabetes decreased GLP-1R expression and protective action on the renal endothelium by increasing its degradation via ubiquitination and enhancing phospho–c-Raf(Ser338) and Ang II activation of phospho-Erk1/2. EC-PKCβ2Tg mice exhibited decreased GLP-1R expression and increased phospho–c-Raf(Ser338), leading to enhanced effects of Ang II. Diabetic EC-PKCβ2Tg mice exhibited greater loss of endothelial GLP-1R expression and exendin-4–protective actions and exhibited more albuminuria and mesangial expansion than diabetic controls. These results showed that the renal protective effects of GLP-1 were mediated via the inhibition of Ang II actions on cRaf(Ser259) and diminished by diabetes because of PKCβ activation and the increased degradation of GLP-1R in the glomerular endothelial cells.

Selection and genetic (co)variance in bighorn sheep

Abstract: Genetic theory predicts that directional selection should deplete additive genetic variance for traits closely related to fitness, and may favor the maintenance of alleles with antagonistically pleiotropic effects on fitness-related traits. Trait heritability is therefore expected to decline with the degree of association with fitness, and some genetic correlations between selected traits are expected to be negative. Here we demonstrate a negative relationship between trait heritability and association with lifetime reproductive success in a wild population of bighorn sheep (Ovis canadensis) at Ram Mountain, Alberta, Canada. Lower heritability for fitness-related traits, however, was not wholly a consequence of declining genetic variance, because those traits showed high levels of residual variance. Genetic correlations estimated between pairs of traits with significant heritability were positive. Principal component analyses suggest that positive relationships between morphometric traits constitute the main axis of genetic variation. Trade-offs in the form of negative genetic or phenotypic correlations among the traits we have measured do not appear to constrain the potential for evolution in this population.

The Euchromatic and Heterochromatic Landscapes Are Shaped by Antagonizing Effects of Transcription on H2A.Z Deposition

Abstract: A role for variant histone H2A.Z in gene expression is now well established but little is known about the mechanisms by which it operates. Using a combination of ChIP–chip, knockdown and expression profiling experiments, we show that upon gene induction, human H2A.Z associates with gene promoters and helps in recruiting the transcriptional machinery. Surprisingly, we also found that H2A.Z is randomly incorporated in the genome at low levels and that active transcription antagonizes this incorporation in transcribed regions. After cessation of transcription, random H2A.Z quickly reappears on genes, demonstrating that this incorporation utilizes an active mechanism. Within facultative heterochromatin, we observe a hyper accumulation of the variant histone, which might be due to the lack of transcription in these regions. These results show how chromatin structure and transcription can antagonize each other, therefore shaping chromatin and controlling gene expression.

Frontiers of biogeography : new directions in the geography of nature

Abstract: Preface - List of Contributors - Introduction: - PART I: PALEOBIOGEOGRAPHY - Introduction - Cenozoic and Mesozoic Paleogeography - Arid Lands Paleobiogeography - Quaternary Biogeography - Biogeography on a Dynamic Earth - PART II: PHYLOGEOGRAPHY AND DIVERSIFICATION - Introduction - The Past and Future Roles of Phylogeography in Historical Biogeography - Range Expansion, Extinction, and Biogeographic Congruence - Reticulations in Historical Biogeography - PART III: DIVERSITY GRADIENTS - Introduction - Beyond Species Richness - The Global Diversity Gradient - Diversity Emerging - Dynamic Hypotheses of Richness on Islands and Continents - PART IV: MARINE BIOGEOGRAPHY - Introduction - Island Life - A Marine Center of Origin - Pattern and Process in Marine Biogeography - PART V: CONSERVATION BIOLOGY - Introduction - How Do Biological Invasions Alter Diversity Patterns? - GIS-Based Predictive Biogeography in the Context of Conservation - Applying Species-Area Relationships to the Conservation of Species Diversity - Conservation Biogeography in Oceanic Archipelagoes - Concluding Remarks - References - Index -

The CHIPS Randomized Controlled Trial (Control of Hypertension in Pregnancy Study): Is Severe Hypertension Just an Elevated Blood Pressure?

Abstract: To determine whether clinical outcomes differed by occurrence of severe hypertension in the international CHIPS trial (Control of Hypertension in Pregnancy Study), adjusting for the interventions of “less tight” (target diastolic blood pressure [dBP] 100 mm Hg) versus “tight” control (target dBP 85 mm Hg). In this post-hoc analysis of CHIPS data from 987 women with nonsevere nonproteinuric preexisting or gestational hypertension, mixed effects logistic regression was used to compare the following outcomes according to occurrence of severe hypertension, adjusting for allocated group and the influence of baseline factors: CHIPS primary (perinatal loss or high-level neonatal care for >48 hours) and secondary outcomes (serious maternal complications), birth weight 9 /L, elevated liver enzymes with symptoms, maternal length of stay ≥10 days, and maternal readmission before 6 weeks postpartum. Three hundred and thirty-four (34.1%) women in CHIPS developed severe hypertension that was associated with all outcomes examined except for maternal readmission ( P =0.20): CHIPS primary outcome, birth weight P 9 /L ( P =0.006), and prolonged hospital stay ( P =0.03). The association between severe hypertension and serious maternal complications was seen only in less tight control ( P =0.02). Adjustment for preeclampsia (464, 47.3%) did not negate the relationship between severe hypertension and the CHIPS primary outcome ( P P =0.005), delivery at P P P =0.02). Severe hypertension is a risk marker for adverse maternal and perinatal outcomes, independent of BP control or preeclampsia co-occurrence. Clinical Trial Registration— URL: http://pre-empt.cfri.ca/. Unique identifier: ISRCTN 71416914. URL: https://www.clinicaltrials.gov/. Unique identifier: NCT01192412.