102 research outputs found

    Down-Regulation of GABAA Receptor via Promiscuity with the Vasoactive Peptide Urotensin II Receptor. Potential Involvement in Astrocyte Plasticity

    Get PDF
    GABAA receptor (GABAAR) expression level is inversely correlated with the proliferation rate of astrocytes after stroke or during malignancy of astrocytoma, leading to the hypothesis that GABAAR expression/activation may work as a cell proliferation repressor. A number of vasoactive peptides exhibit the potential to modulate astrocyte proliferation, and the question whether these mechanisms may imply alteration in GABAAR-mediated functions and/or plasma membrane densities is open. The peptide urotensin II (UII) activates a G protein-coupled receptor named UT, and mediates potent vasoconstriction or vasodilation in mammalian vasculature. We have previously demonstrated that UII activates a PLC/PIPs/Ca2+ transduction pathway, via both Gq and Gi/o proteins and stimulates astrocyte proliferation in culture. It was also shown that UT/Gq/IP3 coupling is regulated by the GABAAR in rat cultured astrocytes. Here we report that UT and GABAAR are co-expressed in cerebellar glial cells from rat brain slices, in human native astrocytes and in glioma cell line, and that UII inhibited the GABAergic activity in rat cultured astrocytes. In CHO cell line co-expressing human UT and combinations of GABAAR subunits, UII markedly depressed the GABA current (ÎČ3Îł2>α2ÎČ3Îł2>α2ÎČ1Îł2). This effect, characterized by a fast short-term inhibition followed by drastic and irreversible run-down, is not relayed by G proteins. The run-down partially involves Ca2+ and phosphorylation processes, requires dynamin, and results from GABAAR internalization. Thus, activation of the vasoactive G protein-coupled receptor UT triggers functional inhibition and endocytosis of GABAAR in CHO and human astrocytes, via its receptor C-terminus. This UII-induced disappearance of the repressor activity of GABAAR, may play a key role in the initiation of astrocyte proliferation

    Power Inequality in Inter-communal Structures: The Simulated Impact of a Reform in the Case of the Municipalities in Western France

    No full text
    International audienceThis paper deals with an important issue concerning democratic government: how delegates are to be allocated among jurisdictions in a federal system. More precisely, we analyze the effect of the 2010 inter-municipal reform in France, which changed the allocation of delegates between municipalities within their inter-communal structures. Using the theory of power indices and a unique set of data gathering 377 inter-municipal structures for three French regions, we compare the fairness of the distribution of municipal delegates prior to the 2010 reform to that of the new distribution, by simulating the impact of the 2010 reform. We show that this inter-communal reform may have increased power inequalities among municipalities belonging to the same inter-communal structure.Cet article s’intĂ©resse Ă  une dimension importante d’un gouvernement dĂ©mocratique : la rĂ©partition des dĂ©lĂ©guĂ©s Ă©lus entre collectivitĂ©s dans une fĂ©dĂ©ration. Plus prĂ©cisĂ©ment, nous analysons l’effet d’une rĂ©forme votĂ©e en France en 2010 et qui a modifiĂ© la rĂ©partition des dĂ©lĂ©guĂ©s des communes au sein de leur intercommunalitĂ©. En mobilisant la thĂ©orie des indices de pouvoir et un jeu de donnĂ©es uniques renseignant les caractĂ©ristiques de 377 structures intercommunales dans trois rĂ©gions françaises, nous comparons l’équitĂ© de la rĂ©partition des dĂ©lĂ©guĂ©s municipaux avant la rĂ©forme de 2010 et l’équitĂ© aprĂšs cette rĂ©forme, en simulant ses effets. Nous montrons que la rĂ©forme des intercommunalitĂ©s a dĂ» accroĂźtre les inĂ©galitĂ©s de pouvoir entre communes membres d’une mĂȘme intercommunalitĂ©

    Power Inequality in Inter-municipal Structures: The Simulated Impact of a Reform in the Case of the Municipalities in Western France

    No full text
    This paper deals with an important issue concerning democratic government : how delegates are to be allocated among jurisdictions in a federal system. More precisely, we analyse the effect of the 2010 inter-municipal reform in France, which changed the allocation of delegates between municipalities within their inter-municipal structures. Using the theory of power indices and a unique set of data gathering 377 inter-municipal structures for three French regions, we compare the fairness of the distribution of municipal delegates prior to the 2010 reform to that of the newdistribution, by simulating the impact of the 2010 reform. We showthat this inter-municipal reformmay have increased power inequalities among municipalities belonging to the same inter-municipal structure.Cet article s’intĂ©resse Ă  une dimension importante d’un gouvernement dĂ©mocratique : la rĂ©partition des dĂ©lĂ©guĂ©s Ă©lus entre collectivitĂ©s dans une fĂ©dĂ©ration. Plus prĂ©cisĂ©ment, nous analysons l’effet d’une rĂ©forme votĂ©e en France en 2010 et qui amodifiĂ© la rĂ©partition des dĂ©lĂ©guĂ©s des communes au sein de leur intercommunalitĂ©. Enmobilisant la thĂ©orie des indices de pouvoir et un jeu de donnĂ©es uniques renseignant les caractĂ©ristiques de 377 structures intercommunales dans trois rĂ©gions françaises, nous comparons l’équitĂ© de la rĂ©partition des dĂ©lĂ©guĂ©smunicipaux avant la rĂ©forme de 2010 et l’équitĂ© aprĂšs cette rĂ©forme, en simulant ses effets. Nous montrons que la rĂ©forme des intercommunalitĂ©s a dĂ» accroĂźtre les inĂ©galitĂ©s de pouvoir entre communes membres d’une mĂȘme intercommunalitĂ©.Abidi Zineb, Leprince Matthieu, Merlin Vincent. Power Inequality in Inter-municipal Structures: The Simulated Impact of a Reform in the Case of the Municipalities in Western France. In: Économie & prĂ©vision, n°217, 2020. pp. 65-87

    Power Inequality in Inter-municipal Structures: The Simulated Impact of a Reform in the Case of the Municipalities in Western France

    No full text
    This paper deals with an important issue concerning democratic government: how delegates are to be allocated among jurisdictions in a federal system. More precisely, we analyse the effect of the 2010 inter-municipal reform in France, which changed the allocation of delegates between municipalities within their inter-municipal structures. Using the theory of power indices and a unique set of data gathering 377 inter-municipal structures for three French regions, we compare the fairness of the distribution of municipal delegates prior to the 2010 reform to that of the new distribution, by simulating the impact of the 2010 reform. We show that this inter-municipal reform may have increased power inequalities among municipalities belonging to the same inter-municipal structure.Cet article s’intĂ©resse Ă  une dimension importante d’un gouvernement dĂ©mocratique : la rĂ©partition des dĂ©lĂ©guĂ©s Ă©lus entre collectivitĂ©s dans une fĂ©dĂ©ration. Plus prĂ©cisĂ©ment, nous analysons l’effet d’une rĂ©forme votĂ©e en France en 2010 et qui a modifiĂ© la rĂ©partition des dĂ©lĂ©guĂ©s des communes au sein de leur intercommunalitĂ©. En mobilisant la thĂ©orie des indices de pouvoir et un jeu de donnĂ©es uniques renseignant les caractĂ©ristiques de 377 structures intercommunales dans trois rĂ©gions françaises, nous comparons l’équitĂ© de la rĂ©partition des dĂ©lĂ©guĂ©s municipaux avant la rĂ©forme de 2010 et l’équitĂ© aprĂšs cette rĂ©forme, en simulant ses effets. Nous montrons que la rĂ©forme des intercommunalitĂ©s a dĂ» accroĂźtre les inĂ©galitĂ©s de pouvoir entre communes membres d’une mĂȘme intercommunalitĂ©

    Vers une ville climato-intelligente : L’IOT au service du suivi des ülots de chaleur urbain

    No full text
    La ville intelligente (Smart City) doit faire face Ă  diffĂ©rents enjeux : optimisation de la consommation des ressources (eau, Ă©nergie), accĂšs Ă  l’information pour ses usagers (transport, parking
), bien-ĂȘtre au quotidien (environnement, amĂ©nagement du territoire, sĂ©curitĂ©) et anticipation des changements (climatiques, mode de vie et de travail
).L’observation du climat urbain est devenue ainsi essentielle et a connu un essor considĂ©rable au cours des derniĂšres dĂ©cennies. La croissance rapide des villes, en termes de population, a entraĂźnĂ© une augmentation des activitĂ©s urbaines et la crĂ©ation d’ülots de chaleur (ICU).Cette note prĂ©sente la solution mise en Ɠuvre pour l'observation de l'ICU Ă  Rennes. Le partenariat Ă©tabli entre LETG-Rennes, Rennes MĂ©tropole et les SociĂ©tĂ©s Wi6Labs et Alkante ont permis de dĂ©ployer un rĂ©seau de capteurs en temps rĂ©el s’appuyant sur la technologie LoRaWan. Ce projet a Ă©tĂ© cofinancĂ© par la Zone Atelier Armorique du CNRS, la ville de Rennes et Rennes MĂ©tropole

    Device and method for electrochemically releasing a composition in a controlled manner

    No full text
    According to a first aspect, the invention relates to a device (10) for electrochemically releasing a composition and comprising: one working electrode (30) comprising an electroactive conjugated polymer (40) containing or doped with said composition, a counter electrode (50), and a reference electrode (60). The device (10) is characterized in that it comprises electrical means (95, 100; 320; 165, 180) connected to the working electrode (30) and to the counter electrode (50) for obtaining at said working electrode (30) at least one composition releasing sequence (65) with respect to said reference electrode (60), each composition releasing sequence (65) comprising: a first voltametric pulse (70), followed by a rest period (80) during which no current is able to flow through said working electrode (30), followed by a second voltametric pulse (90), followed by an intermediate period (160) during which no current is able to flow through said working electrode (30)
    • 

    corecore