1,072 research outputs found

    RÎle de HCaRG/COMMD5 dans le carcinome à cellules rénales : une histoire de transition.

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    Dans les annĂ©es 2000, la Dre Johanne Tremblay et son Ă©quipe identifient un gĂšne rĂ©gulĂ© nĂ©gativement par le calcium extracellulaire dans les glandes parathyroĂŻdiennes de rat hypertendu (SHR). Initialement nommĂ© Hypertension-related calcium regulated gene (HCaRG), puis COMM domain-containing 5 (COMMD5), ce gĂšne codant pour une petite protĂ©ine de 24,67 kDa fait partie d’une famille de 10 protĂ©ines ayant une structure carboxy-terminale homologue nommĂ©e domaine COMM. De nombreux rĂŽles ont Ă©tĂ© associĂ©s Ă  cette famille de protĂ©ines et l’analyse expressionnelle dans diffĂ©rents types de cancers montre une modulation, laissant penser qu’elles auraient un rĂŽle oncogĂ©nique ou suppresseur de tumeurs. Les Ă©tudes ont dĂ©montrĂ© que COMMD5 entraine une maturation des jonctions cellulaires, une diminution de la prolifĂ©ration et favorise la migration cellulaire. La surexpression de COMMD5 dans les tubules proximaux de rein accĂ©lĂšre la rĂ©paration suite Ă  un dommage aigu en limitant d’une part la prolifĂ©ration tout en favorisant la migration et la re-diffĂ©renciation cellulaire. Partant de ces observations, nous avons focalisĂ© nos Ă©tudes sur le dĂ©veloppement du carcinome Ă  cellules rĂ©nales, une pathologie affectant 300 000 personnes chaque annĂ©e dans le monde. L’hypothĂšse que nous avons Ă©mise Ă©tait que COMMD5 puisse potentiellement jouer un rĂŽle anti-oncogĂ©nique dans le cancer du rein en contrĂŽlant la prolifĂ©ration et la diffĂ©renciation cellulaires. Afin de vĂ©rifier notre hypothĂšse, nous avons Ă©tudiĂ© le rĂŽle de COMMD5 dans le maintien de l’intĂ©gritĂ© Ă©pithĂ©liale des cellules via la rĂ©gulation de la transition Ă©pithĂ©lio-mĂ©senchymateuse (EMT) et le contrĂŽle du rĂ©cepteur du facteur de croissance Ă©pidermique (EGFR). Nos rĂ©sultats ont dĂ©montrĂ© que COMMD5 est diminuĂ©e dans les carcinomes rĂ©naux et est corrĂ©lĂ©e avec la survie des patients. La prĂ©sence du facteur de transcription induit par l’hypoxie 1 (HIF1α), exprimĂ© dans la majoritĂ© des tumeurs solides rĂ©nales a induit une diminution de COMMD5. La perte de COMMD5 dans les cellules de tubules proximaux de reins humains (HK-2) a favorisĂ© la dĂ©-diffĂ©renciation et la tumorigĂ©nicitĂ© des cellules, mĂ©diĂ©es par l’activation de la transition Ă©pithĂ©lio-mĂ©senchymateuse. De plus, cette perte de COMMD5 a entrainĂ© Ă©galement une rĂ©organisation du cytosquelette d’actine ayant pour consĂ©quence la dĂ©rĂ©gulation endosomale du rĂ©cepteur de l’EGF et favorisant une activation prolongĂ©e. Dans les carcinomes rĂ©naux, la surexpression de COMMD5 a diminuĂ© la prolifĂ©ration cellulaire suivie d’une re-diffĂ©renciation grĂące Ă  deux mĂ©canismes. D’une part, COMMD5 a rĂ©gulĂ© nĂ©gativement la protĂ©ine HIF1α, induisant ainsi une transition mĂ©senchymo-Ă©pithĂ©liale (MET), tout en sĂ©questrant le facteur de transcription SNAIL dans le cytoplasme. D’autre part, COMMD5 contrĂŽle nĂ©gativement l’expression transcriptionnelle des rĂ©cepteurs ErbB par une hypermĂ©thylation de leurs promoteurs. Dans son ensemble, les rĂ©sultats innovant de cette thĂšse dĂ©montrent que COMMD5 est un gĂšne ayant des caractĂ©ristiques anti-oncogĂ©niques en contrĂŽlant la diffĂ©renciation cellulaire via le mĂ©canisme de transition Ă©pithĂ©lio-mĂ©senchymateux et la rĂ©gulation de l’expression des rĂ©cepteurs ErbB.In the 2000s, Dr. Johanne Tremblay and her team identified a gene that was negatively regulated by extracellular calcium in hypertensive rat parathyroid glands. Originally named Hypertension-related calcium regulated gene (HCaRG) and renamed COMM Domaincontaining 5 (COMMD5), this gene encoding a small protein of 24.67 kDa is part of a family of 10 proteins sharing a homologous structure in the carboxy-terminal position named COMM domain. Many roles have been associated and expressional analysis of different types of cancer shows a modulation suggesting that they have an oncogenic or tumor suppressor roles. Studies have shown that COMMD5 induces maturation of the cell junctions, decreased cell proliferation and promotes migration. The overexpression of COMMD5 in the renal proximal tubules accelerates repair by promoting cell proliferation and ultimately induces cell migration and redifferentiation after acute injury. Based on these observations, we focused on the development of renal cell carcinoma, a disease affecting 300,000 people each year worldwide. Our hypothesis is that COMMD5 plays a tumor suppressor role in kidney cancer by controlling cell proliferation and differentiation. To test our hypothesis, we investigated the role of COMMD5 in maintaining the epithelial integrity of cells through the regulation of epithelial to mesenchymal transition (EMT) and the control of epidermal growth factor receptors (EGFR). The results showed that COMMD5 is decreased in kidney carcinomas resulting of a great negative indicator of the survival prognostic. The presence of hypoxia-inducible factor 1a (HIF1α), expressed in the majority of solid tumors, leads to a decrease of COMMD5 in the proximal tubule cells (HK-2). Inhibition of COMMD5 promotes dedifferentiation and tumorigenicity of cells mediated by epithelial to mesenchymal transition. The loss of COMMD5 induces a reorganization of the actin cytoskeleton resulting in endosomal dysregulation of the EGFR receptor and promoting its activation. In renal cell carcinoma, COMMD5 overexpression decreases cell proliferation and induces their redifferentiation by two mechanisms: firstly, COMMD5 induces an inhibition of the HIF1α protein expression resulting in a mesenchymal to epithelial transition and sequesters the SNAIL transcription factor in the cytoplasm; secondly, COMMD5 negatively regulates the transcriptional expression of the ErbB receptors. Taken together, these results of this thesis show that COMMD5 is a gene showing tumor suppressor characteristics by controlling cellular differentiation and by regulating the expression of ErbB receptors

    Systematic review of conservation interventions to promote voluntary behavior change

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    Understanding human behavior is vital to developing interventions that effectively lead to proenvironmental behavior change, whether the focus is at the individual or societal level. However, interventions in many fields have historically lacked robust forms of evaluation, which makes it hard to be confident that these conservation interventions have successfully helped protect the environment. We conducted a systematic review to assess how effective nonpecuniary and nonregulatory interventions have been in changing environmental behavior. We applied the Office of Health Assessment and Translation systematic review methodology. We started with more than 300,000 papers and reports returned by our search terms and after critical appraisal of quality identified 128 individual studies that merited inclusion in the review. We classified interventions by thematic area, type of intervention, the number of times audiences were exposed to interventions, and the length of time interventions ran. Most studies reported a positive effect (n = 96). The next most common outcome was no effect (n = 28). Few studies reported negative (n = 1) or mixed (n = 3) effects. Education, prompts, and feedback interventions resulted in positive behavior change. Combining multiple interventions was the most effective. Neither exposure duration nor frequency affected the likelihood of desired behavioral change. Comparatively few studies tested the effects of voluntary interventions on non-Western populations (n = 17) or measured actual ecological outcome behavior (n = 1). Similarly, few studies examined conservation devices (e.g., energy-efficient stoves) (n = 9) and demonstrations (e.g., modeling the desired behavior) (n = 5). There is a clear need to both improve the quality of the impact evaluation conducted and the reporting standards for intervention results

    Flagship individuals in biodiversity conservation

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    Flagship species are an important tool for mobilizing support for conservation. Here, we extend this concept to include individual organisms, whose characteristics, fates, and connections to people can garner public attention, attract conservation support, and spur activism. Flagship individuals typically share a similar suite of characteristics, including (1) species-level traits associated with charisma; (2) individual traits that are unique or distinctive; (3) a high degree of exposure to humans; and (4) a known, noteworthy life history or fate. The interplay between these characteristics and human agency establishes unique connections between flagship individuals and people, and generates widespread media attention. We discuss how the selection and promotion of flagship individuals can inspire empathy and, ultimately, conservation action. Finally, we identify the limitations of the flagship individual approach, while arguing that, if carefully and strategically implemented, it has the potential to produce substantial benefits for conservation policy and practice

    Evolution of hypoxia and hypoxia-inducible factor asparaginyl hydroxylase regulation in chronic kidney disease

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    Background The roles of hypoxia and hypoxia inducible factor (HIF) during chronic kidney disease (CKD) are much debated. Interventional studies with HIF-α activation in rodents have yielded contradictory results. The HIF pathway is regulated by prolyl and asparaginyl hydroxylases. While prolyl hydroxylase inhibition is a well-known method to stabilize HIF-α, little is known about the effect asparaginyl hydroxylase factor inhibiting HIF (FIH). Methods We used a model of progressive proteinuric CKD and a model of obstructive nephropathy with unilateral fibrosis. In these models we assessed hypoxia with pimonidazole and vascularization with three-dimensional micro-computed tomography imaging. We analysed a database of 217 CKD biopsies from stage 1 to 5 and we randomly collected 15 CKD biopsies of various severity degrees to assess FIH expression. Finally, we modulated FIH activity in vitro and in vivo using a pharmacologic approach to assess its relevance in CKD. Results In our model of proteinuric CKD, we show that early CKD stages are not characterized by hypoxia or HIF activation. At late CKD stages, some areas of hypoxia are observed, but these are not colocalizing with fibrosis. In mice and in humans, we observed a downregulation of the HIF pathway, together with an increased FIH expression in CKD, according to its severity. Modulating FIH in vitro affects cellular metabolism, as described previously. In vivo, pharmacologic FIH inhibition increases the glomerular filtration rate of control and CKD animals and is associated with decreased development of fibrosis. Conclusions The causative role of hypoxia and HIF activation in CKD progression is questioned. A pharmacological approach of FIH downregulation seems promising in proteinuric kidney disease

    Allergic Rhinitis and its Impact on Asthma (ARIA) Phase 4 (2018) : Change management in allergic rhinitis and asthma multimorbidity using mobile technology

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    Allergic Rhinitis and its Impact on Asthma (ARIA) has evolved from a guideline by using the best approach to integrated care pathways using mobile technology in patients with allergic rhinitis (AR) and asthma multimorbidity. The proposed next phase of ARIA is change management, with the aim of providing an active and healthy life to patients with rhinitis and to those with asthma multimorbidity across the lifecycle irrespective of their sex or socioeconomic status to reduce health and social inequities incurred by the disease. ARIA has followed the 8-step model of Kotter to assess and implement the effect of rhinitis on asthma multimorbidity and to propose multimorbid guidelines. A second change management strategy is proposed by ARIA Phase 4 to increase self-medication and shared decision making in rhinitis and asthma multimorbidity. An innovation of ARIA has been the development and validation of information technology evidence-based tools (Mobile Airways Sentinel Network [MASK]) that can inform patient decisions on the basis of a self-care plan proposed by the health care professional.Peer reviewe

    Adherence to treatment in allergic rhinitis using mobile technology. The MASK Study

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    Background: Mobile technology may help to better understand the adherence to treatment. MASK-rhinitis (Mobile Airways Sentinel NetworK for allergic rhinitis) is a patient-centred ICT system. A mobile phone app (the Allergy Diary) central to MASK is available in 22 countries. Objectives: To assess the adherence to treatment in allergic rhinitis patients using the Allergy Diary App. Methods: An observational cross-sectional study was carried out on all users who filled in the Allergy Diary from 1 January 2016 to 1 August 2017. Secondary adherence was assessed by using the modified Medication Possession Ratio (MPR) and the Proportion of days covered (PDC) approach. Results: A total of 12143 users were registered. A total of 6949 users reported at least one VAS data recording. Among them, 1887 users reported >= 7 VAS data. About 1195 subjects were included in the analysis of adherence. One hundred and thirty-six (11.28%) users were adherent (MPR >= 70% and PDC = 70% and PDC = 1.50) and 176 (14.60%) were switchers. On the other hand, 832 (69.05%) users were non-adherent to medications (MPR Conclusion and clinical relevance: Adherence to treatment is low. The relative efficacy of continuous vs on-demand treatment for allergic rhinitis symptoms is still a matter of debate. This study shows an approach for measuring retrospective adherence based on a mobile app. This also represents a novel approach for analysing medication-taking behaviour in a real-world setting.Peer reviewe

    Measurement of the tt¯tt¯ production cross section in pp collisions at √s=13 TeV with the ATLAS detector

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    A measurement of four-top-quark production using proton-proton collision data at a centre-of-mass energy of 13 TeV collected by the ATLAS detector at the Large Hadron Collider corresponding to an integrated luminosity of 139 fb−1 is presented. Events are selected if they contain a single lepton (electron or muon) or an opposite-sign lepton pair, in association with multiple jets. The events are categorised according to the number of jets and how likely these are to contain b-hadrons. A multivariate technique is then used to discriminate between signal and background events. The measured four-top-quark production cross section is found to be 26+17−15 fb, with a corresponding observed (expected) significance of 1.9 (1.0) standard deviations over the background-only hypothesis. The result is combined with the previous measurement performed by the ATLAS Collaboration in the multilepton final state. The combined four-top-quark production cross section is measured to be 24+7−6 fb, with a corresponding observed (expected) signal significance of 4.7 (2.6) standard deviations over the background-only predictions. It is consistent within 2.0 standard deviations with the Standard Model expectation of 12.0 ± 2.4 fb

    Search for neutral long-lived particles in pp collisions at √s = 13 TeV that decay into displaced hadronic jets in the ATLAS calorimeter

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    A search for decays of pair-produced neutral long-lived particles (LLPs) is presented using 139 fb−1 of proton-proton collision data collected by the ATLAS detector at the LHC in 2015–2018 at a centre-of-mass energy of 13 TeV. Dedicated techniques were developed for the reconstruction of displaced jets produced by LLPs decaying hadronically in the ATLAS hadronic calorimeter. Two search regions are defined for different LLP kinematic regimes. The observed numbers of events are consistent with the expected background, and limits for several benchmark signals are determined. For a SM Higgs boson with a mass of 125 GeV, branching ratios above 10% are excluded at 95% confidence level for values of c times LLP mean proper lifetime in the range between 20 mm and 10 m depending on the model. Upper limits are also set on the cross-section times branching ratio for scalars with a mass of 60 GeV and for masses between 200 GeV and 1 TeV. [Figure not available: see fulltext.

    Measurement and interpretation of same-sign W boson pair production in association with two jets in pp collisions at s = 13 TeV with the ATLAS detector

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    This paper presents the measurement of fducial and diferential cross sections for both the inclusive and electroweak production of a same-sign W-boson pair in association with two jets (W±W±jj) using 139 fb−1 of proton-proton collision data recorded at a centre-of-mass energy of √s = 13 TeV by the ATLAS detector at the Large Hadron Collider. The analysis is performed by selecting two same-charge leptons, electron or muon, and at least two jets with large invariant mass and a large rapidity diference. The measured fducial cross sections for electroweak and inclusive W±W±jj production are 2.92 ± 0.22 (stat.) ± 0.19 (syst.)fb and 3.38±0.22 (stat.)±0.19 (syst.)fb, respectively, in agreement with Standard Model predictions. The measurements are used to constrain anomalous quartic gauge couplings by extracting 95% confdence level intervals on dimension-8 operators. A search for doubly charged Higgs bosons H±± that are produced in vector-boson fusion processes and decay into a same-sign W boson pair is performed. The largest deviation from the Standard Model occurs for an H±± mass near 450 GeV, with a global signifcance of 2.5 standard deviations

    Search for pair production of squarks or gluinos decaying via sleptons or weak bosons in final states with two same-sign or three leptons with the ATLAS detector

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    A search for pair production of squarks or gluinos decaying via sleptons or weak bosons is reported. The search targets a final state with exactly two leptons with same-sign electric charge or at least three leptons without any charge requirement. The analysed data set corresponds to an integrated luminosity of 139 fb−1 of proton-proton collisions collected at a centre-of-mass energy of 13 TeV with the ATLAS detector at the LHC. Multiple signal regions are defined, targeting several SUSY simplified models yielding the desired final states. A single control region is used to constrain the normalisation of the WZ + jets background. No significant excess of events over the Standard Model expectation is observed. The results are interpreted in the context of several supersymmetric models featuring R-parity conservation or R-parity violation, yielding exclusion limits surpassing those from previous searches. In models considering gluino (squark) pair production, gluino (squark) masses up to 2.2 (1.7) TeV are excluded at 95% confidence level
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