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Carrière Audrey Lagarde Damien Jeanson Yannick Portais Jean-Charles Galinier Anne Ader Isabelle Casteilla Louis 《Journal of physiology and biochemistry》2020,76(2):241-250
Journal of Physiology and Biochemistry - Thermogenic (brown and beige) adipose tissues improve glucose and lipid homeostasis and therefore represent putative targets to cure obesity and related... 相似文献
34.
Samantha J. Morin Jeff Bowman Robby R. Marrotte Marie‐Jose Fortin 《Ecology and evolution》2020,10(17):9396-9409
The Canada lynx (Lynx canadensis) and the bobcat (Lynx rufus) are closely related species with overlap at their range peripheries, but the factors that limit each species and the interactions between them are not well understood. Habitat selection is a hierarchical process, in which selection at higher orders (geographic range, home range) may constrain selection at lower orders (within the home range). Habitat selection at a very fine scale within the home range has been less studied for both lynx and bobcat compared to selection at broader spatiotemporal scales. To compare this fourth‐order habitat selection by the two species in an area of sympatry, we tracked lynx and bobcat during the winters of 2017 and 2018 on the north shore of Lake Huron, Ontario. We found that both lynx and bobcat selected shallower snow, higher snowshoe hare abundance, and higher amounts of coniferous forest at the fourth order. However, the two species were spatially segregated at the second order, and lynx were found in areas with deeper snow, more snowshoe hare, and more coniferous forest. Taken together, our findings demonstrate that the lynx and bobcat select different resources at the second order, assorting along an environmental gradient in the study area, and that competition is unlikely to be occurring between the two species at finer scales. 相似文献
35.
Plant and Soil - Land cover change (LCC) from natural forest (NF) to plantations (PF) has occurred worldwide over the past several decades. However, the different LCC effects on soil aggregate C... 相似文献
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Olwen M. Grace Oscar A. Pérez-Escobar Eve J. Lucas Maria S. Vorontsova Gwilym P. Lewis Barnaby E. Walker Lúcia G. Lohmann Sandra Knapp Peter Wilkie Tiina Sarkinen Iain Darbyshire Eimear Nic Lughadha Alexandre Monro Yannick Woudstra Sebsebe Demissew A. Muthama Muasya Sandra Díaz William J. Baker Alexandre Antonelli 《Trends in plant science》2021,26(5):433-441
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Sébastien Ottaviani Anna Moltó Hang-Korng Ea Séverine Neveu Ghislaine Gill Lauren Brunier Elisabeth Palazzo Olivier Meyer Pascal Richette Thomas Bardin Yannick Allanore Frédéric Lioté Maxime Dougados Philippe Dieudé 《Arthritis research & therapy》2013,15(5):R123
Introduction
Gout is a common arthritis that occurs particularly in patients who frequently have associated comorbidities that limit the use of conventional therapies. The main mechanism of crystal-induced inflammation is interleukin-1 production by activation of the inflammasome. We aimed to evaluate the efficacy and tolerance of anakinra in gouty patients.Methods
We conducted a multicenter retrospective review of patients receiving anakinra for gouty arthritis. We reviewed the response to treatment, adverse events and relapses.Results
We examined data for 40 gouty patients (32 men; mean age 60.0 ± 13.9 years) receiving anakinra. Mean disease duration was 8.7 ± 8.7 years. All patients showed contraindications to and/or failure of at least two conventional therapies. Most (36; 90%) demonstrated good response to anakinra. Median pain on a 100-mm visual analog scale was rapidly decreased (73.5 (70.0 to 80.0) to 25.0 (20.0 to 32.5) mm, P <0.0001), as was median C-reactive protein (CRP) level (130.5 (55.8 to 238.8) to 16.0 (5.0 to 29.5) mg/l, P <0.0001). After a median follow-up of 7.0 (2.0 to 13.0) months, relapse occurred in 13 patients after a median delay of 15.0 (10.0 to 70.0) days. Seven infectious events, mainly with long-term use of anakinra, were noted.Conclusions
Anakinra may be efficient in gouty arthritis, is relatively well tolerated with short-term use, and could be a relevant option in managing gouty arthritis when conventional therapies are ineffective or contraindicated. Its long-term use could be limited by infectious complications. 相似文献38.
Julian Bertrand Bertrand Liagre Lamia Ghezali Jean-Louis Beneytout David Yannick Leger 《Apoptosis : an international journal on programmed cell death》2013,18(7):836-850
Cyclooxygenase-2 (COX-2) has been found to be highly expressed in many types of cancers and to contribute to tumorigenesis via the inhibition of apoptosis, increased angiogenesis and invasiveness. In hematological malignancies, COX-2 expression was found to correlate with poor patient prognosis. However, the exact role of COX-2 expression in these malignancies, and particularly in erythroleukemias, remains unclear. The aim of this work was to describe and understand the relationships between COX-2 expression and apoptosis rate in erythroleukemia cells after apoptosis induction by several anticancer agents. We used three different erythroleukemia cell lines in which COX-2 expression was modulated by transfection with either COX-2 siRNA or COX-2 cDNA. These cellular models were then treated with apoptosis inducers and apoptosis onset and intensity was followed. Cell signalling was evaluated in unstimulated transfected cells or after apoptosis induction. We found that COX-2 inhibition rendered erythroleukemia cells more sensitive to apoptosis induction and that in cells overexpressing COX-2 apoptosis induction was reduced. We demonstrated that COX-2 inhibition decreased the pro-survival Akt signalling and activated the negative regulator of Akt signalling, phosphatase and tensin homologue deleted on chromosome 10 (PTEN). Conversely, in COX-2 overexpressing cells, Akt signalling was activated and PTEN was inhibited. In these last cells, inhibition of casein kinase 2 or Akt signalling restored sensitivity to apoptotic agents. Our findings highlighted that COX-2 can positively regulate Akt signalling mostly through PTEN inhibition, partly via casein kinase 2 activation, and enhances survival of erythroleukemia cells exposed to anticancer agents. 相似文献
39.
Marion Fiorentino Guillaume Bastard Malick Sembène Sonia Fortin Pierre Traissac Edwige Landais Christèle Icard-Vernière Frank T. Wieringa Jacques Berger 《PloS one》2013,8(12)
Background
Urban areas in West Africa are not immune to undernutrition with recent urbanization and high food prices being important factors. School children often have a poor nutritional status, potentially affecting their health and schooling performance. Yet, generally school children do not benefit from nutrition programs. The objective of the study was to assess the anthropometric and micronutrient status of children from state schools in the Dakar area.Methods
School children (n = 604) aged from 5 to 17 y (52.5% girls, 47.5% ≥10 y) were selected through a two-stage random cluster sample of children attending urban primary state schools in the Dakar area (30 schools × 20 children). The prevalence of stunting (height-for-age<−2 z-scores) and thinness (BMI-for-age<−2 z-scores, WHO 2006, and three grades of thinness corresponding to BMI of 18.5, 17.0 and 16.0 kg/m2 in adults) were calculated from weight and height. Hemoglobin, plasma concentrations of ferritin (FER), transferrin receptors (TfR), retinol binding protein (RBP), and zinc, and urinary iodine concentrations were measured. Correction factors were used for FER and RBP in subjects with inflammation determined with C-reactive protein and α1-acid-glycoprotein.Results
4.9% of children were stunted, 18.4% were thin, 5.6% had severe thinness (BMI-for-age<−3 z-scores). Only one child had a BMI-for-age>2 z-scores. Prevalence of anemia, iron deficiency and iron deficiency anemia was 14.4%, 39.1% and 10.6% respectively. 3.0% had vitamin A deficiency, 35.9% a marginal vitamin A status, and 25.9% zinc deficiency. Urinary iodine was <50 µg/L in 7.3% of children and ≥200 µg/L in 22.3%. The prevalence of marginal vitamin A, zinc deficiency, high TfR was significantly higher in boys than in girls (P<0.05). Height-for-age and retinol were significantly lower in participants ≥10 y and <10 y respectively.Conclusion
Undernutrition, especially thinness, iron and zinc deficiencies in school children in the Dakar area requires special targeted nutrition interventions. 相似文献40.
Qing Zhao Ermias T. Azeria Mélanie-Louise Le Blanc Jér?me Lema?tre Daniel Fortin 《PloS one》2013,8(11)
Ecosystem-based forest management strives to develop silvicultural practices that best emulate natural disturbances such as wildfire to conserve biodiversity representative of natural forest ecosystems. Yet, current logging practices alter forest structure and reduce the proportion of old-growth forest and, consequently, can exert long-term effects on the dynamics of forest biota. The stand- and landscape-scale factors driving bird community dynamics in post-disturbance environment remain poorly understood. In this study, we examined bird community dynamics along successional gradients in boreal ecosystems originating from fire and logging in landscapes dominated by old-growth forest. We tested if bird species richness and community compositions in clear-cutting stands became comparable to those in natural stands after 70 years, and identified the relative contributions of stand- and landscape-scale forest attributes in bird community dynamics. Based on records of bird occurrences at 185 field sites in natural and clearcutting stands, we demonstrate that (1) both forest structures and bird communities underwent evident changes along successional gradients in post-clearcutting environment; (2) bird species richness and community composition in 60- to 70-years-old clearcutting stands still differed from those in 50- to 79-years-old natural stands, in spite of the fact that most forest attributes of clearcutting stands became comparable to those of natural stands after 40 years; and (3) landscape disturbances contributed more than stand characteristics in explaining the lack of convergence of mature forest species, residents, and short-distance migrants in post-clearcutting environment. Our study points out that more regards should be paid to improve the landscape configuration of the managed forests, and implies that old-growth forest retention within logged areas, combined with selection cutting and prolonged logging rotations, can better emulate fire and alleviate forest harvesting effects on bird community assemblages typical of natural boreal ecosystem. 相似文献