PREVALENCE DES CARDIOPATHIES RHUMATISMALES CHEZ LES JEUNES COLLEGIENS A PARAKOU EN 2012 (BENIN).

RESUME : L’objectif était de déterminer la prévalence des cardiopathies rhumatismales dans le Collège d’Enseignement Général (CEG) Okédama de Parakou. Une étude transversale et descriptive a été menée sur deux mois (07 Mai au 05 Juillet 2012). Etaient inclus, tous les élèves présents, ayant accepté de participer à l’étude et dont les parents ont signé le consentement écrit. Le diagnostic de maladie rhumatismale a été posé sur la base des critères de Jones. La cardite rhumatismale a été retenue sur la base des critères échocardiographiques. Au total, 483 élèves ont été inclus. L’âge moyen était de 14,2 ±3,2 ans et la sex-ratio M/F de 0,46. Au terme des investigations, aucun élève n’a présenté de critères majeurs de Jones mais l’accumulation de deux critères mineurs a été retrouvée dans 1,9% des cas. La preuve biologique d’une infection à streptocoque bêta hémolytique du groupe A n’a été faite chez aucun élève. Finalement, aucun cas de cardiopathie rhumatismale n’a été retrouvé dans cet établissement. Une étude à grande échelle est nécessaire pour vérifier ces données

Evaluation of the role of endothelin in aortic stenosis

International audienceIntroductionCalcified aortic stenosis (AS) is the most common acquired valvulopathy for which there is still no pharmacological treatment. Endothelin-1 (ET-1) is not only a powerful vasoconstrictor but also a pro-inflammatory and pro-fibrotic peptide whose role in AS remains unclear.ObjectiveThe aim of this study was to characterize the role of ET-1 in the aortic valve calcification.MethodValvular endothelial cells (VEC), isolated from human aortic valves, were cultured in a cell perfusion system to assess ET-1 production in different fluid flow shear stress conditions. In addition, valvular interstitial cells (VIC) were cultured in a pro-calcifying culture medium with or without small-molecule and monoclonal antibody ETA and ETB receptor antagonists or agonists receptor ETB IRL-1620 during 10 days. Aortic valves from rats were also cultured and stimulated with ET-1 antagonists. Calcium content was assessed using an o-cresolphtalein-based assay and fluorescence by Osteosens. VEC prepro-ET-1 and VIC osteogenic mRNA expression levels were evaluated by RTqPCR.ResultsTurbulent shear stress, mimicking the flow conditions at the aortic side of the valve increased VEC prepro-ET-1 mRNA expression level and ET-1 release as compared to laminar shear stress. Unexpectedly, calcium content of aortic valves was increased after blockade of ETB receptor and this effect was potentiated by concomitant blockade of ETA receptor. In contrast, ETB receptor agonist decreased calcium content. The mRNA expression of osteopontin, RUNX2, and BMP2 was similarly increased by ETA and ETB blockade.ConclusionThese results support a protective role of the endothelin system against the development of AS. Further studies are warranted to characterize the intracellular pathways and to confirm these results in in vivo models

Minimal tillage and intermittent flooding farming systems show a potential reduction in the proliferation of Anopheles mosquito larvae in a rice field in Malanville, Northern Benin

Background Irrigation systems have been identified as one of the factors promoting malaria disease around agricultural farms in sub-Saharan Africa. However, if improved water management strategy is adopted during rice cultivation, it may help to reduce malaria cases among human population living around rice fields. This study aimed to assess the impact of the different irrigation practices on malaria transmission, as well as to evaluate the water management system that will best mitigate malaria transmission in Malanville, Benin. Methods Knowledge, Attitude and Practice (KAP) study was conducted on 104 households staying on and around the rice fields in Malanville. The study focused on the frequency of mosquito bites and preventive measures against malaria as well as soil preparation and rice planting methods. Mosquito larvae density was assessed in different water management system: continuous flooding (CF) or intermittent flooding (IF), deep tillage (DT) or minimal tillage (MT) and normal levelling (NL) or abnormal levelling (AL) in an experimental hut set-up. Larvae were collected using dipping methods and their density was determined. Results Three tillage systems, which include the use of tiller, plow and hoe, were identified on the rice field. Continuous flooding was the only irrigation system used by farmers. Retrospective data from Malanville Health Centre revealed higher malaria cases during rice production season, which was also confirmed by field participants. The density ofAnopheleslarvae was reduced by 80.8%, 30.8% and 40.7% (P = 0.000) during transplanting, tillering and maturation periods, respectively with intermittent flooding compared to continuous flooding. In addition, a clear reduction of larva density was observed with both intermittent flooding systems applied to minimal tillage (MT + IF + NL) and intermittent flooding applied to deep tillage (DT + IF + AL), showing that intermittent flooding could reduce the abundance of malaria vector in rice fields. Conclusion Recommending intermittent flooding technology for rice cultivation may not only be useful for water management but could also be an intentional strategy to control mosquitoes vector-borne diseases around rice farms