Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome associated with COVID-19: An Emulated Target Trial Analysis.

RATIONALE: Whether COVID patients may benefit from extracorporeal membrane oxygenation (ECMO) compared with conventional invasive mechanical ventilation (IMV) remains unknown. OBJECTIVES: To estimate the effect of ECMO on 90-Day mortality vs IMV only Methods: Among 4,244 critically ill adult patients with COVID-19 included in a multicenter cohort study, we emulated a target trial comparing the treatment strategies of initiating ECMO vs. no ECMO within 7 days of IMV in patients with severe acute respiratory distress syndrome (PaO2/FiO2 <80 or PaCO2 ≥60 mmHg). We controlled for confounding using a multivariable Cox model based on predefined variables. MAIN RESULTS: 1,235 patients met the full eligibility criteria for the emulated trial, among whom 164 patients initiated ECMO. The ECMO strategy had a higher survival probability at Day-7 from the onset of eligibility criteria (87% vs 83%, risk difference: 4%, 95% CI 0;9%) which decreased during follow-up (survival at Day-90: 63% vs 65%, risk difference: -2%, 95% CI -10;5%). However, ECMO was associated with higher survival when performed in high-volume ECMO centers or in regions where a specific ECMO network organization was set up to handle high demand, and when initiated within the first 4 days of MV and in profoundly hypoxemic patients. CONCLUSIONS: In an emulated trial based on a nationwide COVID-19 cohort, we found differential survival over time of an ECMO compared with a no-ECMO strategy. However, ECMO was consistently associated with better outcomes when performed in high-volume centers and in regions with ECMO capacities specifically organized to handle high demand. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/)

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 60 109 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: ‘Typical’ 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 (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P &lt; 0.001). 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

Operando Spectroscopic studies of methnol conversion over supported oxomolybdates catalysts

A study combining DFT calculations and complementary "in situ" and "operando" techniques is presented. The structure of oxomolybdate catalyst was found to be mandatory for the selected reaction. More precisely, our results converge to the same statement: isolated [MoO4] moieties are not active in methanol oxidation to formaldehyde

TiO2-supported oxorhenate catalysts: A multi-techniques operando study

The methanol conversion to methylal over a series of TiO2-anatase supported oxorhenate catalysts was investigated using operando UV-visible and Raman spectroscopy and compared to the catalytic activities afforded by a classical test. In dehydrated catalysts, two distinct structures were clearly identified and correlated to different catalytic behavior upon CH3OH/He – CH3OH/He/O2 – O2 cycling. Such differences, intimately linked to the rhenium surface coverage, are proposed to reflect different degrees of polymerization

A well-defined silica-supported dinuclear tungsten(III) amido species: synthesis, characterization and reactivity

International audienceGrafting of [W2(NMe2)6] onto dehydroxylated silica affords the well-defined surface species [(Si–O)W2(NMe2)5], characterized by elemental analysis, and infrared, Raman and NMR spectroscopies, and the catalytic reactivity of this supported tungsten(III) d3–d3 dimer and of its alkoxide derivatives towards alkynes has been probed

Adalimumab therapy in pediatric Crohn’s Disease: a two-year follow-up comparing ‘top-down’ and ‘step-up’ strategies.

International audienceObjective: European Crohn’s Colitis Organization (ECCO) and the European Society of Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) guidelines recommend the early use of anti-TNF biologicals in pediatric Crohn disease (CD) patients with positive predictors for poor outcome.The objective of the present study was to compare early "Top-Down" use of Adalimumab (ADA) immunomodulator/biologics-naïve patients to conventional "Step-Up" management.Methods: One hundred and twenty consecutive patients with a confirmed diagnosis of CD and treated with Adalimumab (ADA) between 2008 and 2019 were included and allocated to the ADA-Top Down (n=59) or ADA-Step Up group (n=61). The primary endpoint was prolonged steroid-/enteral nutrition-free clinical remission at 24 months, defined by a wPCDAI < 12.5. Clinical and biological data were collected at 12 and 24 months.Results: At start of ADA, disease activity was comparable between the ADA-Top Down group and the ADA-Step Up group (wPCDAI=31 ± 16 versus 31.3 ± 15.2 respectively, p=0.84). At 24 months, the remission rate was significantly higher in the ADA-Top Down group (73% versus 51%, p<0.01). After propensity score, the Top-Down strategy is still more effective than the Step-Up strategy in maintaining remission at 24 months (HR=0.36, 95%CI[0.15-0.87], p=0.02). Patients in the ADA-Top Down group were mainly on monotherapy compared to patients in the ADA-Step Up group (53/55 versus 28/55 respectively, p<0.001). Serum levels of Adalimumab were higher in the ADA-Top Down group than in the ADA-Step Up group (12.8µg/ml±4.3 versus 10.4µg/ml±3.9 respectively, p<0.01).There were no serious adverse events.Conclusion: Early use of ADA appears to be more effective in maintaining relapse-free remission at 2 years, while using it as monotherapy. These findings further favor the recommendation of early anti-TNF use in high-risk CD patients

Spectroscopie d'absorption X et catalyse hétérogène

La connaissance détaillée des mécanismes de réaction en catalyse hétérogène nécessite une description précise de la géométrie et de l'environnement local des sites actifs qui sont déterminants pour les performances catalytiques (conversion, sélectivité). La spectroscopie d'absorption X (XANES et EXAFS) est à l'heure actuelle l'une des techniques les plus appropriées pour déterminer la structure de ces phases. Elle donne en effet accès à la configuration électronique (état d'oxydation) et à la géométrie (nature et nombre d'atomes environnants) de l'atome absorbeur. Le développement des méthodologies XAS in situ et operando résolues dans le temps permet maintenant de disposer de ces informations aussi bien lors de l'activation du catalyseur qu'au cours de la réaction catalytique, et ce dans les conditions réelles de travail. Cet article souligne les potentialités actuelles de la spectroscopie d'absorption X en présentant divers exemples représentatifs de la catalyse hétérogène et couvrant les étapes successives du cycle de vie d'un catalyseur, allant du suivi de la synthèse à la genèse de la phase active lors de son activation, jusqu'à l'étude de l'évolution des sites en cours de réaction. Enfin des approches récentes sont présentées pour l'étude de catalyseurs modèles impliquant d'une part des développements instrumentaux et d'autre part l'interprétation des données spectrales par modélisation

Âge et sexualité

La sexualité est une question d’âge comme le rappellent les régulations juridiques, les catégories médicales et la production littéraire et artistique. À travers des études sur l’érotisme en Grèce archaïque, l’invention médicale de la ménopause à l’époque moderne, les débats des années 1970 sur la sexualité des mineurs ou encore l’homoérotisme vieux-jeune en Chine post-maoïste, ce dossier de Clio montre comment les normes d’âge et de sexualité contribuent différemment à chaque période historique à la définition et à la recomposition des normes de genre

Impact on disease mortality of clinical, biological, and virological characteristics at hospital admission and overtime in COVID‐19 patients

International audienc

Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome Associated with COVID-19: An Emulated Target Trial Analysis

International audienc