La démarche diagnostique des troubles cognitifs chez l'âgé

Cet article retrace une recherche qualitative pluridisciplinaire. Les cinq auteurs - anthropologues, médecin psychiatre, psychologue et sociologue - ont développé une collaboration autour d'une problématique récurrente chez les personnes âgées: les troubles cognitifs associés à l'âge, les difficultés à les diagnostiquer et à communiquer le diagnostic aux patients et à leurs proches. Huit patients et leurs proches se sont rencontrés séparément lors de deux séries d'entretiens sur l'annonce du diagnostic Mild Cognitive Impairment (MCI). Les résultats montrent que la communication du diagnostic MCI n'insuffle pas un tournant dans la trajectoire des patients. Les propos des experts semblent n'avoir qu'un faible impact sur la compréhension qu'ont les patients et leurs accompagnants de la santé mentale des sujets diagnostiqués.

Réunion internationale de physique, chimie, biologie, Congrès du Palais de la découverte, Paris, octobre 1937. 3, Rayons cosmiques / J. Clay, P. M. S. Blackett, G. Lemaitre,... [et al.]

Collection : Actualités scientifiques et industrielles ; 720

Les hormones sexuelles. 2, Ovulation, menstruation, gestation / par E. Allen, G. Hartman, S. Zuckerman... [et al.]

Collection : Actualités scientifiques et industrielles ; 602, 6

G alpha-q/11 protein plays a key role in insulin-induced glucose transport in 3T3-L1 adipocytes.

We evaluated the role of the G alpha-q (Galphaq) subunit of heterotrimeric G proteins in the insulin signaling pathway leading to GLUT4 translocation. We inhibited endogenous Galphaq function by single cell microinjection of anti-Galphaq/11 antibody or RGS2 protein (a GAP protein for Galphaq), followed by immunostaining to assess GLUT4 translocation in 3T3-L1 adipocytes. Galphaq/11 antibody and RGS2 inhibited insulin-induced GLUT4 translocation by 60 or 75%, respectively, indicating that activated Galphaq is important for insulin-induced glucose transport. We then assessed the effect of overexpressing wild-type Galphaq (WT-Galphaq) or a constitutively active Galphaq mutant (Q209L-Galphaq) by using an adenovirus expression vector. In the basal state, Q209L-Galphaq expression stimulated 2-deoxy-D-glucose uptake and GLUT4 translocation to 70% of the maximal insulin effect. This effect of Q209L-Galphaq was inhibited by wortmannin, suggesting that it is phosphatidylinositol 3-kinase (PI3-kinase) dependent. We further show that Q209L-Galphaq stimulates PI3-kinase activity in p110alpha and p110gamma immunoprecipitates by 3- and 8-fold, respectively, whereas insulin stimulates this activity mostly in p110alpha by 10-fold. Nevertheless, only microinjection of anti-p110alpha (and not p110gamma) antibody inhibited both insulin- and Q209L-Galphaq-induced GLUT4 translocation, suggesting that the metabolic effects induced by Q209L-Galphaq are dependent on the p110alpha subunit of PI3-kinase. In summary, (i) Galphaq appears to play a necessary role in insulin-stimulated glucose transport, (ii) Galphaq action in the insulin signaling pathway is upstream of and dependent upon PI3-kinase, and (iii) Galphaq can transmit signals from the insulin receptor to the p110alpha subunit of PI3-kinase, which leads to GLUT4 translocation.

G-banded karyotype of the alpine shrew, Sorex alpinus (Mammalia, Soricidae), from the Sumava Mts

The G-banded karyotype of two individuals of the alpine shrew Sorer alpinus collected from the Sumava Mountains (Czech Republic) is presented. The diploid number of chromosomes was 56 and both the morphology and the G-banding pattern of chromosomes appeared to be very similar Gto those reported from the Alps and the Jura Mountains. This is the first report on the G-banded chromosomes of this species outside Switzerland and eastern France.

Les vrais principes de l'église, de la morale et de la raison, sur la constitution civile du clergé, renversés par les faux évêques des départemens, membres de l'Assemblée nationale, prétendue constituante ([Reprod.]) / [par G. N. Maultrot]

Collection : Les archives de la Révolution française ; 8.1417

Structural determinants involved in the activation and regulation of G protein-coupled receptors: lessons from the alpha1-adrenegic receptor subtypes.

The aim of a large number of studies on G protein-coupled receptors was centered on understanding the structural basis of their main functional properties. Here, we will briefly review the results obtained on the alpha1-adrenergic receptor subtypes belonging to the rhodopsin-like family of receptors. These findings contribute, on the one hand, to further understand the molecular basis of adrenergic transmission and, on the other, to provide some generalities on the structure-functional relationship of G protein-coupled receptors.

Characterization of the phosphorylation sites involved in G protein-coupled receptor kinase- and protein kinase C-mediated desensitization of the alpha1B-adrenergic receptor.

Catecholamines as well as phorbol esters can induce the phosphorylation and desensitization of the alpha1B-adrenergic receptor (alpha1BAR). In this study, phosphoamino acid analysis of the phosphorylated alpha1BAR revealed that both epinephrine- and phorbol ester-induced phosphorylation predominantly occurs at serine residues of the receptor. The findings obtained with receptor mutants in which portions of the C-tail were truncated or deleted indicated that a region of 21 amino acids (393-413) of the carboxyl terminus including seven serines contains the main phosphorylation sites involved in agonist- as well as phorbol ester-induced phosphorylation and desensitization of the alpha1BAR. To identify the serines invoved in agonist- versus phorbol ester-dependent regulation of the receptor, two different strategies were adopted, the seven serines were either substituted with alanine or reintroduced into a mutant lacking all of them. Our findings indicate that Ser394 and Ser400 were phosphorylated following phorbol ester-induced activation of protein kinase C, whereas Ser404, Ser408, and Ser410 were phosphorylated upon stimulation of the alpha1BAR with epinephrine. The observation that overexpression of G protein-coupled kinase 2 (GRK2) could increase agonist-induced phosphorylation of Ser404, Ser408, and Ser410, strongly suggests that these serines are the phosphorylation sites of the alpha1BAR for kinases of the GRK family. Phorbol ester-induced phosphorylation of the Ser394 and Ser400 as well as GRK2-mediated phosphorylation of the Ser404, Ser408, and Ser410, resulted in the desensitization of alpha1BAR-mediated inositol phosphate response. This study provides generalities about the biochemical mechanisms underlying homologous and heterologous desensitization of G protein-coupled receptors linked to the activation of phospholipase C.