60 research outputs found
COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study
Background:
The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms.
Methods:
International, prospective observational study of 60â109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms.
Results:
âTypicalâ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (â€â18 years: 69, 48, 23; 85%), older adults (â„â70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each Pâ<â0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country.
Interpretation:
This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men
ContrÎle du métabolisme oxydatif musculaire par les peptides natriurétiques
En marge de leur effet sur la rĂ©gulation de la volĂ©mie, les peptides natriurĂ©tiques Ă©mergent depuis une vingtaine dâannĂ©es comme des hormones mĂ©taboliques reliant lâactivitĂ© cardiaque au mĂ©tabolisme Ă©nergĂ©tique. Des travaux rĂ©cents de notre Ă©quipe soulignent un nouveau rĂŽle de ces peptides dans le contrĂŽle du mĂ©tabolisme oxydatif musculaire et ouvrent de nouvelles perspectives dans lâĂ©tude des maladies chroniques affectant les muscles squelettiques
RÎle physiologique des peptides natriurétiques dans le contrÎle de la mobilisation des lipides chez l'homme
TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF
Aspects physiologiques et physiopathologiques du contrÎle de la lipolyse et de la mobilisation des lipides par les peptides natriurétiques
Nous avons montré que les peptides natriurétiques (PN) exercent un puissant effet lipolytique spécifiquement dans les adipocytes de l'Homme et des Primates. Au niveau cellulaire, leur effet implique la stimulation de récepteurs spécifiques des peptides natriurétiques de type A de la membrane plasmique, la production de GMPc et l'activation de la protéine kinase GMPcdépendante I, médiateur de la phosphorylation de la lipase hormono-sensible et de la stimulation de la lipolyse. Une perfusion locale d'ANP (Atrial Natriuretic Peptide), in situ dans le tissu adipeux sous-cutané via une sonde de microdialyse, augmente la lipolyse et le flux sanguin local chez des sujets de poids normal. Cet effet est altéré chez des individus en surpoids et restauré par un entraßnement en endurance. L'ANP stimule la mobilisation des lipides au cours d'exercices d'endurance. L'administration d'un -bloquant avant l'exercice potentialise paradoxalement cet effet en raison d'une majoration des niveaux circulants d'ANP. Aucune différence sexuelle dans la réponse lipolytique de l'ANP n'a été observée au cours d'un exercice. Une injection intraveineuse d'ANP à dose physiologique induit une mobilisation des lipides. Des concentrations plus fortes d'ANP, telles qu'observées au cours de l'insuffisance cardiaque, stimulent l'oxydation des lipides. L'insuffisance cardiaque s'accompagne d'une élévation chronique et soutenue des taux circulants de PN qui pourrait favoriser l'évolution vers la cachexie. Au contraire, une corrélation inverse entre les niveaux circulants de PN et l'indice de masse corporelle apparaßt chez des sujets obÚses. La base moléculaire de cette corrélation n'a pas été fonctionnellement
démontrée. Des études complémentaires sont nécessaires pour
évaluer clairement le rÎle physiopathologique des PN dans l'obésité et l'insuffisance cardiaque
Ătude du rĂŽle des lipases musculaires dans la rĂ©gulation du mĂ©tabolisme des lipides et de la sensibilitĂ© Ă l'insuline
TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF
Comment optimiser lâutilisation des lipides pendant un exercice physique ? Effet de lâentraĂźnement et diffĂ©rences sexuelles
La sĂ©dentaritĂ© conduit Ă des Ă©tats de surpoids et dâobĂ©sitĂ© dans nos sociĂ©tĂ©s
occidentales. Lâexercice physique a des effets bĂ©nĂ©ïŹques pour rĂ©duire les
réserves lipidiques chez les sujets en surpoids ou obÚses. Cependant, il est
nĂ©cessaire de pratiquer une activitĂ© physique adaptĂ©e qui permettra dâutiliser
au mieux les rĂ©serves lipidiques. Chez lâhomme, trois mĂ©canismes induisent la
lipolyse pendant lâexercice : lâaugmentation des catĂ©cholamines et des peptides
natriurĂ©tiques cardiaques et la baisse de lâinsuline. Pour un exercice physique
modéré, réalisé à jeun, 45 % de la dépense énergétique est fournie par les
lipides. Par contre, lâingestion de sucres diminue la lipolyse et en consĂ©quence
rĂ©duit lâoxydation des lipides. Deux Ă 4 heures aprĂšs la prise alimentaire,
lâutilisation des glucides est 2 fois plus importante que lorsque lâexercice est
réalisé 8 et 12 heures aprÚs la prise alimentaire. Un entraßnement régulier en
endurance augmente lâutilisation des lipides au cours dâexercices rĂ©alisĂ©s Ă
jeun. Quelle que soit lâintensitĂ© de lâeffort, les femmes en surpoids mobilisent
mieux les lipides que les hommes. Cette diffĂ©rence peut sâexpliquer par lâexcĂšs
de masse grasse chez la femme. De plus, lâutilisation des lipides est majorĂ©e
chez la femme aux exercices de faible intensité
Determinants of intramyocellular triglyceride turnover: implications for insulin sensitivity
Les peptides natriurétiques : une nouvelle voie de régulation de la lipolyse chez l'homme
Human fat cell lipolysis was considered until recently to be an exclusive cAMP/protein-kinase A (PKA)-regulated metabolic pathway under the control of catecholamines and insulin. Moreover, exercise-induced lipid mobilization in humans was considered to mainly depend on catecholamine action and interplay between fat cell beta- and alpha2-adrenergic receptors controlling adenylyl cyclase activity and cAMP production. We have recently demonstrated that natriuretic peptides stimulate lipolysis and contribute to the regulation of lipid mobilization in humans. Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) stimulate lipolysis in human isolated fat cells. Activation of the adipocyte plasma membrane type A guanylyl cyclase receptor (NPR-A), increase in intracellular guanosine 3',5'-cyclic monophosphate (cyclic GMP) levels and activation of hormone-sensitive lipase mediate the action of ANP. ANP does not modulate cAMP production and PKA activity. Increment of cGMP induces the phosphorylation of hormone-sensitive lipase and perilipin A via the activation of a cGMP dependent protein kinase-I (cGK-I). Plasma concentrations of glycerol and nonesterified fatty acids are increased by i.v. infusion of ANP in humans. Physiological relevance of the ANP-dependent pathway was demonstrated in young subjects performing physical exercise. ANP plays a role in conjunction with catecholamines in the control of exercise-induced lipid mobilization. This pathway becomes of major importance when subjects are submitted to chronic treatment with a beta-blocker. Oral beta-adrenoceptor blockade suppresses the beta-adrenergic component of catecholamine action in fat cells and potentiates exercise-induced ANP release by the heart. These findings may have several implications whenever natriuretic peptide secretion is altered such as in subjects with left ventricular dysfunction, congestive heart failure and obesity
Phosphodiesterase-5A and neutral endopeptidase activities in human adipocytes do not control atrial natriuretic peptide-mediated lipolysis.
International audienceBACKGROUND AND PURPOSE: Atrial natriuretic peptide (ANP) stimulates lipolysis in human adipocyte through a cGMP signalling pathway, the regulation of which is poorly known. Since phosphodiesterases (PDE) and neutral endopeptidase (NEP) play a major role in the regulation of the biological effects of natriuretic peptides in the cardiovascular and renal systems, we investigated whether these mechanisms could regulate cGMP signalling and ANP-mediated lipolysis in human adipocytes. EXPERIMENTAL APPROACH: The presence of cGMP-specific PDE and NEP in differentiated pre-adipocytes and in mature adipocytes was evaluated by real-time qPCR and Western blot. The effect of non-selective and selective inhibition of these enzymes on ANP-mediated cGMP signalling and lipolysis was determined in isolated mature adipocytes. KEY RESULTS: PDE-5A was expressed in both pre-adipocytes and adipocytes. PDE-5A mRNA and protein levels decreased as pre-adipocytes differentiated (10 days). PDE-5A is rapidly activated in response to ANP stimulation and lowers intracellular cGMP levels. Its selective inhibition by sildenafil partly prevented the decline in cGMP levels. However, no changes in baseline- and ANP-mediated lipolysis were observed under PDE-5 blockade using various inhibitors. In addition, NEP mRNA and protein levels gradually increased during the time-course of pre-adipocyte differentiation. Thiorphan, a selective NEP inhibitor, completely abolished NEP activity in human adipocyte membranes but did not modify ANP-mediated lipolysis. CONCLUSIONS AND IMPLICATIONS: Functional PDE-5A and NEP activities were present in human adipocytes, however these enzymes did not play a major role in the regulation of ANP-mediated lipolysis
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