Utilisation du mélange équimolaire oxygène protoxyde d'azote en milieu préhospitalier

TOULOUSE3-BU Santé-Centrale (315552105) / SudocSudocFranceF

Sensitivity analysis of coniferous forest reflectance with canopy structure and undergrowth characteristics from satellite data and modelling (case study: Landes maritime pine forest)

National audienc

Estimation du LAI dans un écosystème cultivé de pin maritime à partir de mesures de fractions de trouées directionnelles

National audienc

Ex vivo model of herpes simplex virus type I dendritic and geographic keratitis using a corneal active storage machine

International audienceBackground: Herpetic keratitis (HK) models using whole human corneas are essential for studying virus-host relationships, because of high species specificity and the role of interactions between corneal cell populations that cell culture cannot reproduce. Nevertheless, the two current corneal storage methods (hypothermia and organ culture (OC)) do not preserve corneas in good physiological condition, as they are characterized by epithelial abrasion, stromal oedema, and excessive endothelial mortality.Methods: To rehabilitate human corneas intended for scientific use, we used an active storage machine (ASM) that restores two physiological parameters that are essential for corneal homeostasis: intraocular pressure and storage medium renewal (21mmHg and 2.6 μL/min, respectively). ASM storage regenerates a normal multilayer epithelium in 2 weeks. We infected six pairs of corneas unsuitable for graft by inoculating the epithelium with herpes simplex virus type 1 (HSV-1), and compared each ASM-stored cornea with the other cornea stored in the same medium using the conventional OC method.Results: Only corneas in the ASM developed a dendritic (n = 3) or geographic (n = 2) epithelial ulcer reproducing typical HSV-1-induced clinical lesions. Corneas in OC showed only extensive desquamations. None of the uninfected controls showed epithelial damage. Histology, immunohistochemistry, transmission electron microscopy and polymerase chain reaction on corneal tissue confirmed infection in all cases (excluding negative controls).Conclusions: The ASM provides an innovative ex vivo model of HK in whole human cornea that reproduces typical epithelial lesions

One threat, different answers:the impact of COVID-19 pandemic on cornea donation and donor selection across Europe

OBJECTIVES: To assess to which extent the COVID-19 pandemic affected corneal transplantation by virtue of donor selection algorithms in different European countries. DESIGN: Survey. SETTING: 110 eye banks in 26 European countries. PARTICIPANTS: 64 eye banks covering 95% of European corneal transplantation activity. INTERVENTIONS: A questionnaire listing the number of corneas procured and distributed from February to May 2018-2020 was circulated to eye banks. MAIN OUTCOME MEASURES: The primary outcome was the number of corneal procurements. Additional outcomes were national algorithms for donor selection, classified according to their stringency (donors with COVID-19 history, suspected for COVID-19, asymptomatic, PCR testing) and the pandemic severity in each country. We calculated Spearman's correlation coefficient to determine, two by two, the relationship between the 3-month decline in eye banking activity (procurement), the stringency of donor selection algorithm and the grading of pandemic severity (cases and deaths). A partial correlation was run to determine the relationship between decline and stringency while controlling for pandemic severity. RESULTS: Procurements decreased by 38%, 68% and 41%, respectively, in March, April and May 2020 compared with the mean of the previous 2 years, while grafts decreased, respectively, by 28%, 68% and 56% corresponding to 3866 untreated patients in 3 months. Significant disparities between countries and the decrease in activity correlated with stringency in donor selection independent of pandemic severity. CONCLUSIONS: Our data demonstrate significant differences between countries regarding donor screening algorithms based on precautionary principles and, consequently, a decrease in the donor pool, already constrained by a long list of contraindications. Fundamental studies are needed to determine the risk of SARS-CoV-2 transmission by corneal transplantation and guide evidence-based recommendations for donor selection to justify their substantial medical and economic impact

Figures de l’identité

Crise de l’identité collective, revendications communautaires, évolution des modèles sociopolitiques : autant de problématiques qui, malgré leur actualité et leur apparente modernité, constituaient déjà des défis majeurs dans l’Antiquité. Pour qui s’intéresse à la formation, à la transmission et à l’évolution des formes d’autoreprésentation collective, le monde romain offre défait un champ d’investigation privilégié, où les diverses communautés politiques, sociales ou littéraires n’ont eu de cesse d’interroger les fondements de leur identité en érigeant des figures modèles ou des contre-modèles. Fruit de réflexions menées pendant plusieurs années à l’ENS de Lyon par le laboratoire junior EMCA (Étude des modèles culturels dans l’Antiquité), cet ouvrage aborde la question de l’histoire des origines de la cité et des grands hommes du passé, des pratiques sociales de la vie quotidienne ou encore de la perception des différents genres poétiques. Patronné par André Laronde, il réunit les travaux de seize chercheurs, littéraires et historiens, qui, par ces regards croisés, lancent des éclairages nouveaux sur la question de l’identité collective dans le monde romain