110 research outputs found
Voyage dâĂ©tude en Occitanie: " ĂcosystĂšmes forestiers et impact de la gestion sur leur fonctionnement Ă long terme"
A quoi ressemble une forĂȘt sans transformation anthropique majeure, intĂ©rĂȘt de leur Ă©tude, diffĂ©rences fondamentales entre une forĂȘt gĂ©rĂ©e en "bon pĂšre de famille" et un Ă©cosystĂšme forestier naturel. Gestion de la cohabitation dâune activitĂ© pastorale, des ongulĂ©s sauvages (et de leur chasse), de la fourniture de bois de chauffage aux sociĂ©taires et de la production de bois dâĆuvre. ItinĂ©raires sylvicoles adaptĂ©s Ă certains sols chimiquement trĂšs pauvres
ConnectivitĂ© spatiale et diversitĂ© des espĂšces: Mise en place dâun rĂ©seau de conservation dans le Parc National du Mercantour
La thĂ©matique des forĂȘts anciennes et des forĂȘts matures a Ă©tĂ© au cĆur du sĂ©minaire physique du GT ForĂȘt-Eau, avec l'organisation le 27 octobre 2015 d'une journĂ©e d'Ă©changes et de visite, associant une douzaine de partenaires (INRA, IRSTEA, Purpan, RNF, FPNR, CBNMC...). Au delĂ , PNF [Parcs Nationaux de France] continuera Ă suivre les diffĂ©rents projets en cours, menĂ©s par des Parcs nationaux ou d'autres partenaires, et Ă envisager d'autres projets collectifs pour aller plus loin dans la connaissance des forĂȘts anciennes et matures
Inventaire et Ă©valuation des vieilles forĂȘts des PyrĂ©nĂ©es de Midi-PyrĂ©nĂ©es
Les 11, 12 et 13 fĂ©vrier 2016, ce sont dĂ©roulĂ©es les 5e Rencontres Naturalistes de Midi-PyrĂ©nĂ©es dans le Gers, Ă Auch. Tous les 3 ans, ce rendez-vous incontournable des amateurs et professionnels de la biodiversitĂ© de Midi-PyrĂ©nĂ©es et dâailleurs, a rassemblĂ© plus de 600 participants sur les 3 jours. Le succĂšs de cet Ă©vĂ©nement nâaurait pas Ă©tĂ© aussi complet sans lâaide des bĂ©nĂ©voles et des associations partenaires. Les 5e Rencontres Naturalistes se sont ouvertes sur les discours de Nadia BaĂŻtiche-Moine, Adjointe au Maire dâAuch, de JĂ©rĂŽme Calas, PrĂ©sident de Nature Midi-PyrĂ©nĂ©es et de Ronny Guardia-Mazzoleni, Conseiller rĂ©gional Languedoc-Roussillon-Midi-PyrĂ©nĂ©es. Au cours de ces 3 jours, ce sont prĂšs de 35 communications sur la faune, la flore et les espaces naturels, agricoles et forestiers qui ont Ă©tĂ© prĂ©sentĂ©es : une vĂ©ritable synthĂšse des diffĂ©rents travaux menĂ©s en Midi-PyrĂ©nĂ©es depuis 3 ans dans le domaine de la connaissance et de la prĂ©servation de notre riche patrimoine naturel rĂ©gional. Les nombreux participants dâhorizons divers (associations, conservatoires, services de lâEtat, laboratoires de recherche, Ă©tablissements scolaires, PNR ou collectivitĂ©s) ont eu Ă©galement lâoccasion de profiter des temps de pause pour Ă©changer autour dâune vingtaine de posters scientifiques et de diffĂ©rentes expositions
Lactate dehydrogenases promote glioblastoma growth and invasion via a metabolic symbiosis
Lactate is a central metabolite in brain physiology but also contributes to tumor development. Glioblastoma (GB) is the most common and malignant primary brain tumor in adults, recognized by angiogenic and invasive growth, in addition to its altered metabolism. We show herein that lactate fuels GB anaplerosis by replenishing the tricarboxylic acid (TCA) cycle in absence of glucose. Lactate dehydrogenases (LDHA and LDHB), which we found spatially expressed in GB tissues, catalyze the interconversion of pyruvate and lactate. However, ablation of both LDH isoforms, but not only one, led to a reduction in tumor growth and an increase in mouse survival. Comparative transcriptomics and metabolomics revealed metabolic rewiring involving high oxidative phosphorylation (OXPHOS) in the LDHA/B KO group which sensitized tumors to cranial irradiation, thus improving mouse survival. When mice were treated with the antiepileptic drug stiripentol, which targets LDH activity, tumor growth decreased. Our findings unveil the complex metabolic network in which both LDHA and LDHB are integrated and show that the combined inhibition of LDHA and LDHB strongly sensitizes GB to therapy.publishedVersio
Indole-pyridinyl-ethanones as novel inhibitors of indoleamine-2,3 dioxygenase (IDO), a promising target for anti-cancer immunotherapy
CAGIRE: a wide-field NIR imager for the COLIBRI 1.3 meter robotic telescope
The use of high energy transients such as Gamma Ray Bursts (GRBs) as probes
of the distant universe relies on the close collaboration between space and
ground facilities. In this context, the Sino-French mission SVOM has been
designed to combine a space and a ground segment and to make the most of their
synergy. On the ground, the 1.3 meter robotic telescope COLIBRI, jointly
developed by France and Mexico, will quickly point the sources detected by the
space hard X-ray imager ECLAIRs, in order to detect and localise their
visible/NIR counterpart and alert large telescopes in minutes. COLIBRI is
equipped with two visible cameras, called DDRAGO-blue and DDRAGO-red, and an
infrared camera, called CAGIRE, designed for the study of high redshift GRBs
candidates. Being a low-noise NIR camera mounted at the focus of an
alt-azimutal robotic telescope imposes specific requirements on CAGIRE. We
describe here the main characteristics of the camera: its optical, mechanical
and electronics architecture, the ALFA detector, and the operation of the
camera on the telescope. The instrument description is completed by three
sections presenting the calibration strategy, an image simulator incorporating
known detector effects, and the automatic reduction software for the ramps
acquired by the detector. This paper aims at providing an overview of the
instrument before its installation on the telescope.Comment: Accepted by Experimental Astronom
Cartographie des forĂȘts anciennes de France : objectifs, bilan et perspectives
Il y a dix ans dĂ©marraient les premiers travaux de vectorisation, Ă l'Ă©chelle rĂ©gionale, des forĂȘts de la carte d'Etat-Major, en vue de l'Ă©tablissement d'une carte nationale des forĂȘts Ă longue continuitĂ© de l'Ă©tat boisĂ©. OĂč en est-on aujourd'hui ? Nous faisons le point de l'avancement des travaux et en tirons les premiers enseignements, en rĂ©pondant aux questions suivantes : Quels sont les dĂ©finitions et concepts sous-jacents Ă ces travaux ? Pourquoi cartographier les forĂȘts dites "anciennes" ou "rĂ©centes" ? L'analyse des institutions ayant rĂ©alisĂ© le travail montre que ce sont principalement les milieux de la conservation qui ont Ă©tĂ© moteurs dans ces travaux. Mais la production et la qualitĂ© des produits bois sont aussi concernĂ©s par cette cartographie. Le rĂŽle actuel de puits de carbone des forĂȘts françaises ne peut par exemple se comprendre qu'au travers de cette dynamique forestiĂšre ancienne. Pourquoi une focalisation sur la premiĂšre moitiĂ© du XIXe siĂšcle comme date de rĂ©fĂ©rence ? Que signifie la notion de minimum forestier ? Quelles en sont les limites ? Quels sont les supports de donnĂ©es les plus intĂ©ressantes pour cette cartographie ? Pourquoi la carte d'Etat-Major est une source particuliĂšre d'information, dans l'objectif de la cartographie des forĂȘts anciennes, parmi la multitude de cartes ou statistiques disponibles Ă diffĂ©rentes dates et Ă©chelles ? Quelles sont les mĂ©thodes d'acquisition de la donnĂ©e ? Quelle est la prĂ©cision spatiale des cartes d'occupation du sol obtenues ? Les principaux problĂšmes posĂ©s par l'utilisation de la carte d'Etat-Major seront prĂ©sentĂ©s, ainsi que la façon dont diffĂ©rents projets y ont rĂ©pondu. Quels rĂ©sultats ont Ă©tĂ© obtenus ? Nous reviendrons entre autres sur l'estimation de la surface forestiĂšre française Ă la date de son minimum. Les cartes dĂ©jĂ rĂ©alisĂ©es, sur 33% du territoire, permettent de dessiner avec prĂ©cision et de comparer les changements d'occupation du sol dans diffĂ©rentes rĂ©gions de France, en termes de pourcentage de dĂ©boisement, reboisement et taux de forĂȘt ancienne dans la forĂȘt actuelle. Les Ă©volutions du couvert forestier issues d'autres sources non cartographiques sont-elles confirmĂ©es ? Le lien avec le type de propriĂ©tĂ© fonciĂšre est particuliĂšrement intĂ©ressant Ă analyser. Dans plusieurs zones de France (PyrĂ©nĂ©es, Luberon, Alpes, Lorraine, Nord-Pas-de-Calais...) ont Ă©tĂ© rĂ©alisĂ©s des croisements entre ces cartes et les bases de donnĂ©es rĂ©gionales de relevĂ©s floristiques (Inventaire forestier national, conservatoires botaniques). Ce nouveau type d'analyse permet d'identifier rapidement les espĂšces vĂ©gĂ©tales liĂ©es Ă la continuitĂ© de l'Ă©tat boisĂ©, dites espĂšces de forĂȘts anciennes, et les traits de vie qui leur sont associĂ©s. Nous prĂ©senterons une synthĂšse de ces rĂ©sultats. Dans la moitiĂ© des zones dĂ©jĂ cartographiĂ©es, ce sont toutes les occupations du sol anciennes qui ont Ă©tĂ© numĂ©risĂ©es et non seulement les forĂȘts. Nous Ă©voquerons l'intĂ©rĂȘt de ce cadastre ancien, au-delĂ des seules questions forestiĂšres, pour le suivi de la dynamique Ă long terme des prairies, des milieux humides, des vignes ou des milieux urbanisĂ©s. Les techniques de vectorisation des occupations anciennes du sol Ă©voluent vers une simplification et une accĂ©lĂ©ration qui laisse prĂ©sager une fin du travail plus rapide que prĂ©vue initialement, parfois au dĂ©triment de la qualitĂ©. L'extension Ă la France entiĂšre permettra une vision Ă la fois Ă petite Ă©chelle mais localement prĂ©cise des mouvements des masses forestiĂšres. Nous discuterons les perspectives de recherche et les dĂ©veloppements en cours, ouverts par ces progrĂšs
Natalizumab treatment shows low cumulative probabilities of confirmed disability worsening to EDSS milestones in the long-term setting.
Abstract Background Though the Expanded Disability Status Scale (EDSS) is commonly used to assess disability level in relapsing-remitting multiple sclerosis (RRMS), the criteria defining disability progression are used for patients with a wide range of baseline levels of disability in relatively short-term trials. As a result, not all EDSS changes carry the same weight in terms of future disability, and treatment benefits such as decreased risk of reaching particular disability milestones may not be reliably captured. The objectives of this analysis are to assess the probability of confirmed disability worsening to specific EDSS milestones (i.e., EDSS scores â„3.0, â„4.0, or â„6.0) at 288 weeks in the Tysabri Observational Program (TOP) and to examine the impact of relapses occurring during natalizumab therapy in TOP patients who had received natalizumab for â„24 months. Methods TOP is an ongoing, open-label, observational, prospective study of patients with RRMS in clinical practice. Enrolled patients were naive to natalizumab at treatment initiation or had received â€3 doses at the time of enrollment. Intravenous natalizumab (300âŻmg) infusions were given every 4 weeks, and the EDSS was assessed at baseline and every 24 weeks during treatment. Results Of the 4161 patients enrolled in TOP with follow-up of at least 24 months, 3253 patients with available baseline EDSS scores had continued natalizumab treatment and 908 had discontinued (5.4% due to a reported lack of efficacy and 16.4% for other reasons) at the 24-month time point. Those who discontinued due to lack of efficacy had higher baseline EDSS scores (median 4.5 vs. 3.5), higher on-treatment relapse rates (0.82 vs. 0.23), and higher cumulative probabilities of EDSS worsening (16% vs. 9%) at 24 months than those completing therapy. Among 24-month completers, after approximately 5.5 years of natalizumab treatment, the cumulative probabilities of confirmed EDSS worsening by 1.0 and 2.0 points were 18.5% and 7.9%, respectively (24-week confirmation), and 13.5% and 5.3%, respectively (48-week confirmation). The risks of 24- and 48-week confirmed EDSS worsening were significantly higher in patients with on-treatment relapses than in those without relapses. An analysis of time to specific EDSS milestones showed that the probabilities of 48-week confirmed transition from EDSS scores of 0.0â2.0 to â„3.0, 2.0â3.0 to â„4.0, and 4.0â5.0 to â„6.0 at week 288 in TOP were 11.1%, 11.8%, and 9.5%, respectively, with lower probabilities observed among patients without on-treatment relapses (8.1%, 8.4%, and 5.7%, respectively). Conclusions In TOP patients with a median (range) baseline EDSS score of 3.5 (0.0â9.5) who completed 24 months of natalizumab treatment, the rate of 48-week confirmed disability worsening events was below 15%; after approximately 5.5 years of natalizumab treatment, 86.5% and 94.7% of patients did not have EDSS score increases of â„1.0 or â„2.0 points, respectively. The presence of relapses was associated with higher rates of overall disability worsening. These results were confirmed by assessing transition to EDSS milestones. Lower rates of overall 48-week confirmed EDSS worsening and of transitioning from EDSS score 4.0â5.0 to â„6.0 in the absence of relapses suggest that relapses remain a significant driver of disability worsening and that on-treatment relapses in natalizumab-treated patients are of prognostic importance
The CEP5 Peptide Promotes Abiotic Stress Tolerance, As Revealed by Quantitative Proteomics, and Attenuates the AUX/IAA Equilibrium in Arabidopsis.
Peptides derived from non-functional precursors play important roles in various developmental processes, but also in (a)biotic stress signaling. Our (phospho)proteome-wide analyses of C-TERMINALLY ENCODED PEPTIDE 5 (CEP5)-mediated changes revealed an impact on abiotic stress-related processes. Drought has a dramatic impact on plant growth, development and reproduction, and the plant hormone auxin plays a role in drought responses. Our genetic, physiological, biochemical, and pharmacological results demonstrated that CEP5-mediated signaling is relevant for osmotic and drought stress tolerance in Arabidopsis, and that CEP5 specifically counteracts auxin effects. Specifically, we found that CEP5 signaling stabilizes AUX/IAA transcriptional repressors, suggesting the existence of a novel peptide-dependent control mechanism that tunes auxin signaling. These observations align with the recently described role of AUX/IAAs in stress tolerance and provide a novel role for CEP5 in osmotic and drought stress tolerance
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