Expression and activity of 20α-hydroxysteroid dehydrogenase (AKR1C1) in abdominal subcutaneous and omental adipose tissue in women

We have examined the expression and activity of 20a-hydroxysteroid dehydrogenase (20a-HSD) in abdominal adipose tissue in women. This recently-characterized enzyme from the aldoketoreductase 1C family (AKR1C1) is responsible for the conversion of progesterone into 20a-hydroxyprogesterone. Abdominal subcutaneous (SC) and omental (OM) adipose tissue biopsies were obtained from a sample of 32 women aged 47.7+-5.9 years (BMI: 27.6+-5.0 kg/m2 ) undergoing abdominal hysterectomies. Body composition and body fat distribution measurements were performed before the surgery by dual energy x-ray absorptiometry and computed tomography respectively. The expression of 20a-HSD was determined by real-time RT-PCR, and its activity was measured in whole tissue homogenates. Messenger RNA and activity of the enzyme were detected in both the SC and OM fat depots, the two measures being significantly higher in the SC compartment. Women characterized by a visceral adipose tissue area greater than or equal to 100 cm2 had an increased 20a-HSD conversion rate in their omental adipose tissue compared to women without visceral obesity (13.99+-2.07 vs. 7.92+-0.83 fmol/ug protein/24h, p<0.05). Accordingly, a positive correlation was found between omental adipose tissue 20a-HSD activity and computed tomography-measured visceral adipose tissue area (r=0.36, p<0.05). Significant positive correlations were also found between omental 20a-HSD activity and omental adipocyte diameter (r=0.49, p<0.05) and omental adipose tissue LPL activity (r=0.36, p=0.06). In conclusion, 20a-HSD activity and mRNA were detected in SC and OM adipose tissue in women, and omental 20a-hydroxylation of progesterone was highest in women with visceral obesity. Further studies are required to establish whether local conversion of progesterone may impact on the metabolism and function of adipocytes located within the abdominal cavity

La qualité de vie des citoyens à Alma : résultats de l'enquête de 1998

Cette enquête sur la qualité de vie des citoyens de la municipalité d'Alma s'inscrit dans le projet de « modélisation du suivi des impacts sociaux de l'aluminerie d'Alma ». La première étape de ce projet de recherche longitudinale et mulîimodale consiste à faire le portrait de référence1 d'Alma et de sa région d'appartenance avant la construction de la nouvelle usine. L'enquête sur la qualité de vie des Almatois s'inscrit dans ce projet, se voulant une première mesure des perceptions des citoyens par rapport à ce qui constitue l'essentiel de leur qualité de vie. Elle a été conçue sur le mode longitudinal, pour être répétée dans l'avenir, ce qui permettra de faire le suivi dans l'évolution des perceptions et la mesure de la réalisation des attentes des répondants sur une période de cinq ans, soit avant, pendant et après la construction de la nouvelle usine

A call for benchmarking transposable element annotation methods.

International audienceDNA derived from transposable elements (TEs) constitutes large parts of the genomes of complex eukaryotes, with major impacts not only on genomic research but also on how organisms evolve and function. Although a variety of methods and tools have been developed to detect and annotate TEs, there are as yet no standard benchmarks-that is, no standard way to measure or compare their accuracy. This lack of accuracy assessment calls into question conclusions from a wide range of research that depends explicitly or implicitly on TE annotation. In the absence of standard benchmarks, toolmakers are impeded in improving their tools, annotators cannot properly assess which tools might best suit their needs, and downstream researchers cannot judge how accuracy limitations might impact their studies. We therefore propose that the TE research community create and adopt standard TE annotation benchmarks, and we call for other researchers to join the authors in making this long-overdue effort a success

Bovine Polledness – An Autosomal Dominant Trait with Allelic Heterogeneity

The persistent horns are an important trait of speciation for the family Bovidae with complex morphogenesis taking place briefly after birth. The polledness is highly favourable in modern cattle breeding systems but serious animal welfare issues urge for a solution in the production of hornless cattle other than dehorning. Although the dominant inhibition of horn morphogenesis was discovered more than 70 years ago, and the causative mutation was mapped almost 20 years ago, its molecular nature remained unknown. Here, we report allelic heterogeneity of the POLLED locus. First, we mapped the POLLED locus to a ∼381-kb interval in a multi-breed case-control design. Targeted re-sequencing of an enlarged candidate interval (547 kb) in 16 sires with known POLLED genotype did not detect a common allele associated with polled status. In eight sires of Alpine and Scottish origin (four polled versus four horned), we identified a single candidate mutation, a complex 202 bp insertion-deletion event that showed perfect association to the polled phenotype in various European cattle breeds, except Holstein-Friesian. The analysis of the same candidate interval in eight Holsteins identified five candidate variants which segregate as a 260 kb haplotype also perfectly associated with the POLLED gene without recombination or interference with the 202 bp insertion-deletion. We further identified bulls which are progeny tested as homozygous polled but bearing both, 202 bp insertion-deletion and Friesian haplotype. The distribution of genotypes of the two putative POLLED alleles in large semi-random sample (1,261 animals) supports the hypothesis of two independent mutations

Simulating rewetting events in intermittent rivers and ephemeral streams: a global analysis of leached nutrients and organic matter

Climate change and human pressures are changing the global distribution and extent of intermittent rivers and ephemeral streams (IRES), which comprise half of the global river network area. IRES are characterized by periods of flow cessation, during which channel substrates accumulate and undergo physico‐chemical changes (preconditioning), and periods of flow resumption, when these substrates are rewetted and release pulses of dissolved nutrients and organic matter (OM). However, there are no estimates of the amounts and quality of leached substances, nor is there information on the underlying environmental constraints operating at the global scale. We experimentally simulated, under standard laboratory conditions, rewetting of leaves, riverbed sediments, and epilithic biofilms collected during the dry phase across 205 IRES from five major climate zones. We determined the amounts and qualitative characteristics of the leached nutrients and OM, and estimated their areal fluxes from riverbeds. In addition, we evaluated the variance in leachate characteristics in relation to selected environmental variables and substrate characteristics. We found that sediments, due to their large quantities within riverbeds, contribute most to the overall flux of dissolved substances during rewetting events (56‐98%), and that flux rates distinctly differ among climate zones. Dissolved organic carbon, phenolics, and nitrate contributed most to the areal fluxes. The largest amounts of leached substances were found in the continental climate zone, coinciding with the lowest potential bioavailability of the leached organic matter. The opposite pattern was found in the arid zone. Environmental variables expected to be modified under climate change (i.e. potential evapotranspiration, aridity, dry period duration, land use) were correlated with the amount of leached substances, with the strongest relationship found for sediments. These results show that the role of IRES should be accounted for in global biogeochemical cycles, especially because prevalence of IRES will increase due to increasing severity of drying events

Endocrinologie du tissu adipeux

Titre de l'écran-titre (visionné le 31 juillet 2023

Verified Given Clause Procedures

International audienceResolution and superposition provers rely on the given clause procedure to saturate clause sets. Using Isabelle/HOL, we formally verify four variants of the procedure: the well-known Otter and DISCOUNT loops as well as the newer iProver and Zipperposition loops. For each of the variants, we show that the procedure guarantees saturation, given a fair data structure to store the formulas that wait to be selected. Our formalization of the Zipperposition loop clarifies some fine points previously misunderstood in the literature

Unifying Splitting

AVATAR is an elegant and effective way to split clauses in a saturation prover using a SAT solver. But is it refutationally complete? And how does it relate to other splitting architectures? To answer these questions, we present a unifying framework that extends a saturation calculus (e.g., superposition) with splitting and that embeds the result in a prover guided by a SAT solver. The framework also allows us to study locking, a subsumption-like mechanism based on the current propositional model. Various architectures are instances of the framework, including AVATAR, labeled splitting, and SMT with quantifiers

Superposition for Higher-Order Logic

We recently designed two calculi as stepping stones towards superposition for full higher-order logic: Boolean-free λ-superposition and superposition for first-order logic with interpreted Booleans. Stepping on these stones, we finally reach a sound and refutationally complete calculus for higher-order logic with polymorphism, extensionality, Hilbert choice, and Henkin semantics. In addition to the complexity of combining the calculus’s two predecessors, new challenges arise from the interplay between λ-terms and Booleans. Our implementation in Zipperposition outperforms all other higher-order theorem provers and is on a par with an earlier, pragmatic prototype of Booleans in Zipperposition