Les relations adolescents-musées : comparaison France/États-Unis

À travers un état des lieux des relations adolescents-musées en France et aux États-Unis, l’auteur analyse le rôle et la spécificité de l’offre éducative diffusée par des dispositifs muséaux réservés aux adolescents en visite libre, montre que les efforts déployés ne sont pas toujours couronnés de succès et qu’au-delà du cadre de l’institution muséale, se pose la question de la place concédée à la classe d’âge adolescente dans la société

Chromatin remodeling — a novel strategy to control excessive alcohol drinking

Harmful excessive use of alcohol has a severe impact on society and it remains one of the major causes of morbidity and mortality in the population. However, mechanisms that underlie excessive alcohol consumption are still poorly understood, and thus available medications for alcohol use disorders are limited. Here, we report that changing the level of chromatin condensation by affecting DNA methylation or histone acetylation limits excessive alcohol drinking and seeking behaviors in rodents. Specifically, we show that decreasing DNA methylation by inhibiting the activity of DNA methyltransferase (DNMT) with systemic administration of the FDA-approved drug, 5-azacitidine (5-AzaC) prevents excessive alcohol use in mice. Similarly, we find that increasing histone acetylation via systemic treatment with several histone deacetylase (HDAC) inhibitors reduces mice binge-like alcohol drinking. We further report that systemic administration of the FDA-approved HDAC inhibitor, SAHA, inhibits the motivation of rats to seek alcohol. Importantly, the actions of both DNMT and HDAC inhibitors are specific for alcohol, as no changes in saccharin or sucrose intake were observed. In line with these behavioral findings, we demonstrate that excessive alcohol drinking increases DNMT1 levels and reduces histone H4 acetylation in the nucleus accumbens (NAc) of rodents. Together, our findings illustrate that DNA methylation and histone acetylation control the level of excessive alcohol drinking and seeking behaviors in preclinical rodent models. Our study therefore highlights the possibility that DNMT and HDAC inhibitors can be used to treat harmful alcohol abuse

Control of aversion by glycine-gated GluN1/GluN3A NMDA receptors in the adult medial habenula

The unconventional N-methyl-d-aspartate (NMDA) receptor subunits GluN3A and GluN3B can, when associated with the other glycine-binding subunit GluN1, generate excitatory conductances purely activated by glycine. However, functional GluN1/GluN3 receptors have not been identified in native adult tissues. We discovered that GluN1/GluN3A receptors are operational in neurons of the mouse adult medial habenula (MHb), an epithalamic area controlling aversive physiological states. In the absence of glycinergic neuronal specializations in the MHb, glial cells tuned neuronal activity via GluN1/GluN3A receptors. Reducing GluN1/GluN3A receptor levels in the MHb prevented place-aversion conditioning. Our study extends the physiological and behavioral implications of glycine by demonstrating its control of negatively valued emotional associations via excitatory glycinergic NMDA receptors

A novel anxiogenic role for the delta opioid receptor expressed in GABAergic forebrain neurons.

BACKGROUND: The delta opioid receptor (DOR) is broadly expressed throughout the nervous system; it regulates chronic pain, emotional responses, motivation, and memory. Neural circuits underlying DOR activities have been poorly explored by genetic approaches. We used conditional mouse mutagenesis to elucidate receptor function in GABAergic neurons of the forebrain. METHODS: We characterized DOR distribution in the brain of Dlx5/6-CreXOprd1(fl/fl) (Dlx-DOR) mice and tested main central DOR functions through behavioral testing. RESULTS: The DOR proteins were strongly deleted in olfactory bulb and striatum and remained intact in cortex and basolateral amygdala. Olfactory perception, circadian activity, and despair-like behaviors were unchanged. In contrast, locomotor stimulant effects of SNC80 (DOR agonist) and SKF81297 (D1 agonist) were abolished and increased, respectively. The Dlx-DOR mice showed lower levels of anxiety in the elevated plus maze, opposing the known high anxiety in constitutive DOR knockout animals. Also, Dlx-DOR mice reached the food more rapidly in a novelty suppressed feeding task, despite their lower motivation for food reward observed in an operant paradigm. Finally, c-fos protein staining after novelty suppressed feeding was strongly reduced in amygdala, concordant with the low anxiety phenotype of Dlx-DOR mice. CONCLUSIONS: We demonstrate that DORs expressed in the forebrain mediate the described locomotor effect of SNC80 and inhibit D1-stimulated hyperactivity. Our data also reveal an unanticipated anxiogenic role for this particular DOR subpopulation, with a potential novel adaptive role. In emotional responses, DORs exert dual anxiolytic and anxiogenic roles, both of which may have implications in the area of anxiety disorders

Deformation-based Morphometry MRI Reveals Brain Structural Modifications in Living Mu Opioid Receptor Knockout Mice

Mu opioid receptor (MOR) activation facilitates reward processing and reduces pain, and brain networks underlying these effects are under intense investigation. Mice lacking the MOR gene (MOR KO mice) show lower drug and social reward, enhanced pain sensitivity and altered emotional responses. Our previous neuroimaging analysis using Resting-state (Rs) functional Magnetic Resonance Imaging (fMRI) showed significant alterations of functional connectivity (FC) within reward/aversion networks in these mice, in agreement with their behavioral deficits. Here we further used a structural MRI approach to determine whether volumetric alterations also occur in MOR KO mice. We acquired anatomical images using a 7-Tesla MRI scanner and measured deformation-based morphometry (DBM) for each voxel in subjects from MOR KO and control groups. Our analysis shows marked anatomical differences in mutant animals. We observed both local volumetric contraction (striatum, nucleus accumbens, bed nucleus of the stria terminalis, hippocampus, hypothalamus and periacqueducal gray) and expansion (prefrontal cortex, amygdala, habenula, and periacqueducal gray) at voxel level. Volumetric modifications occurred mainly in MOR-enriched regions and across reward/aversion centers, consistent with our prior FC findings. Specifically, several regions with volume differences corresponded to components showing highest FC changes in our previous Rs-fMRI study, suggesting a possible function-structure relationship in MOR KO-related brain differences. In conclusion, both Rs-fMRI and volumetric MRI in live MOR KO mice concur to disclose functional and structural whole-brain level mechanisms that likely drive MOR-controlled behaviors in animals, and may translate to MOR-associated endophenotypes or disease in humans

Les sons de l'hôpital

A l'occasion de ses recherches pour le laboratoire, la sociologue Martine Leroux s'est intéressée à plusieurs reprises au monde de l'hôpital et à ses ambiances. Citons par exemple les recherches : Incidence des facteurs physiques d'environnement sur le bien-être des personnes âgées (1992), Les ambiances des espaces d'accueil du service de radiodiagnostic de l'Institut Gustave Roussy (1999) ou encore A l'écoute de l'hôpital (2003). Ce sont les deux dernières de ces recherches qui nous intéress..

Autour de la Collection Cressound : métadonnées, indexation et valorisation

"Field recording from the top of Hoogh Catherijne". Utrecht, 2013. Sebastiaan ter Burg | CC BY 3.0 http://commons.wikimedia.org/ Dans le cadre du Master 2 Productions et médiations des formes culturelles, parcours documentation à l’Université Pierre-Mendès-France de Grenoble, j’ai effectué mon stage de fin d’études de janvier à juillet 2015 (six mois)  au centre de documentation du laboratoire Cresson. Pendant ce stage, je me suis plus particulièrement intéressé aux questions du traitement do..