L'infection par le VIH chez les femmes en âge de procréer à Sassandra (Côte d'Ivoire)

Le travail, réalisé en 1988-1989, a consisté à comparer les caractéristiques socio-démographiques des femmes en âge de procréer (15-49 ans) d'une sous-préfecture rurale de Côte d'Ivoire (Sassandra) avec leur statut sérologique VIH afin de dégager des variables explicatives de cette séropositivité. Il n'a pas été possible de tester que 521 femmes sur les 1084 qui constituaient la population de départ, mais les deux sous-populations ne diffèrent que par les lieux de naissance et de résidence. La séropositivité tréponémique est élevée, de façon homogène. Pour la séropositivité du VIH, le taux global de séropositivité est de 6,1 plus ou moins 0,02 %, soit un taux intermédiaire (différences non significatives) entre ceux trouvés lors de l'enquête nationale en zone rurale (4,9 %) et en zone urbaine (7,3 %). Ce taux de séropositivité est lié au lieu de naissance (même après ajustement sur le taux de présentation); les femmes nées dans la région sont plus souvent positives que les autres et les femmes nées dans les villages plus souvent que celles nées en ville (p = 0,005 et 0,02). En revanche, les femmes mariées sont moins souvent positives que les femmes non mariées et que celles vivant en union libre (p = 0,02 et 0,0005); la polygamie semble apporter une certaine protection envers le VIH par rapport à la monogamie. Enfin les femmes séropositives ont eu plus souvent des enfants mort-nés et moins souvent des enfants décédés que les femmes séronégatives (p = 0,02 et 0,03). Il est proposé de renforcer les activités de surveillance prénatale et de les renforcer surtout en zone rurale pour prévenir de nouvelles infections par le VIH. (Résumé d'auteur

Temporal sampling helps unravel the genetic structure of naturally occurring populations of a phytoparasitic nematode. 2. Separating the relative effects of gene flow and genetic drift

International audienceStudying wild pathogen populations in natural ecosystems offers the opportunity to better understand the evolutionary dynamics of biotic diseases in crops and to enhance pest control strategies. We used simulations and genetic markers to investigate the spatial and temporal population genetic structure of wild populations of the beet cyst nematode Heterodera schachtii on a wild host plant species, the sea beet (Beta vulgaris spp. maritima), the wild ancestor of cultivated beets. Our analysis of the variation of eight microsatellite loci across four study sites showed that (i) wild H. schachtii populations displayed fine-scaled genetic structure with no evidence of substantial levels of gene flow beyond the scale of the host plant, and comparisons with simulations indicated that (ii) genetic drift substantially affected the residual signals of isolation-by-distance processes, leading to departures from migration–drift equilibrium. In contrast to what can be suspected for (crop) field populations, this showed that wild cyst nematodes have very low dispersal capabilities and are strongly disconnected from each other. Our results provide some key elements for designing pest control strategies , such as decreasing passive dispersal events to limit the spread of virulence among field nematode populations

Potential spironolactone effects on collagen metabolism biomarkers in patients with uncontrolled blood pressure.

BACKGROUND: An increase in myocardial collagen content may contribute to the development of heart failure; this might be inhibited or reversed by mineralocorticoid receptor antagonists (MRAs). We investigated changes in serum concentrations of the collagen synthesis biomarkers N-terminal propeptide of procollagen type III (PIIINP) (primary outcome) and C-terminal propeptide of procollagen type I (PICP) (secondary outcome) after non-randomised initiation of spironolactone as add-on therapy among patients with resistant hypertension enrolled in the 'Anglo-Scandinavian Cardiac Outcomes' trial (ASCOT). METHODS: An age/sex matching plus propensity-scored logistic regression model incorporating variables related to the outcome and spironolactone treatment was created to compare patients treated with spironolactone for a 9-month period versus matched controls. A within-person analysis comparing changes in serum biomarker concentrations in the 9 months before versus after spironolactone treatment was also performed. RESULTS: Patients included in the between-person analysis (n=146) were well matched: the mean age was 63±7 years and 11% were woman. Serum concentrations of PIIINP and PICP rose in 'controls' and fell during spironolactone treatment (adjusted means +0.52 (-0.05 to 1.09) vs -0.41 (-0.97 to 0.16) ng/mL, p=0.031 for PIIINP and +4.54(-1.77 to 10.9) vs -6.36 (-12.5 to -0.21) ng/mL, p=0.023 for PICP). For the within-person analysis (n=173), spironolactone treatment was also associated with a reduction in PICP (beta estimate=-11.82(-17.53 to -6.10) ng/mL, p<0.001) but not in PIIINP levels. CONCLUSIONS: Treatment with spironolactone was associated with a reduction in serum biomarkers of collagen synthesis independently of blood pressure in patients with hypertension, suggesting that spironolactone might exert favourable effects on myocardial collagen synthesis and fibrosis. Whether this effect might contribute to slowing the progression to heart failure is worth investigating

Enseignants et enseignements au cœur de la transmission des savoirs

Ce recueil est consacré à la question de la transmission des savoirs abordée non pas comme un transfert individuel, de personne à personne, dans le cadre de la famille ou de l’atelier, mais comme un système formel combinant de façon plus structurée un ou des enseignements. Cette problématique a fait l’objet de très nombreuses conférences, d’une extrême diversité, présentées lors du 143e Congrès national des sociétés historiques et scientifiques tenu à Paris, en 2018. Leur point commun est principalement de s’interroger sur la transmission des savoirs par l’enseignement, son éventuelle formalisation, ses acteurs, ses méthodes et ses outils, voire ses enjeux. Le Congrès national des sociétés historiques et scientifiques rassemble chaque année universitaires, membres de sociétés savantes et jeunes chercheurs. Ce recueil est issu de travaux présentés lors du 143e Congrès sur le thème « La transmission des savoirs »

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570