Introduction des trocas (Trochus niloticus, L.) à Lifou par transplantation de juvéniles produits en aquaculture

Une opération d'introduction de trocas (#Trochus niloticus L.$) a été effectuée à Lifou (Iles Loyauté) avec des juvéniles produits en aquaculture. Cette opération représente une tentative de constitution à moyen terme d'un stock de trocas exploitable par les pêcheurs locaux. (Résumé d'auteur

Localization of deformation in thin shells under indentation

Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (pages 72-77).We perform a hybrid experimental and numerical study of the localization of deformation in thin spherical elastic shells under indentation. Past a critical indentation, the deformation of the shell ceases to be axisymmetric and sharp points of localized curvature form. In plates, these sharp points are known as d-cones. By way of analogy, regions of localization in shells are referred to as s-cones, for 'shell-cones'. We quantify how the formation and evolution of s-cones is affected by the indenter's curvature. Juxtaposing results from precision model experiments and Finite Element simulations enables the exploration of the frictional nature of the shell-indenter contact. The numerics also allow for a characterization of the relative properties of strain energy focusing, at the different loci of localization. The predictive power of the numerics is taken advantage of to further explore parameter space and perform numerical experiments that are not easily conducted physically. This combined experimental and computational approach allows us to gain invaluable physical insight towards rationalizing this geometrically nonlinear process.by Alice M. Nasto.S.M

Pharmacokinetics, safety, and efficacy of a single co-administered dose of diethylcarbamazine, albendazole and ivermectin in adults with and without Wuchereria bancrofti infection in Cote d\u27Ivoire

BackgroundA single co-administered dose of ivermectin (IVM) plus diethylcarbamazine (DEC) plus albendazole (ALB), or triple-drug therapy, was recently found to be more effective for clearing microfilariae (Mf) than standard DEC plus ALB currently used for mass drug administration programs for lymphatic filariasis (LF) outside of sub-Saharan Africa. Triple-drug therapy has not been previously tested in LF-uninfected individuals from Africa. This study evaluated the pharmacokinetics (PK), safety, and efficacy of triple-drug therapy in people with and without Wuchereria bancrofti infection in West Africa.MethodsIn this open-label cohort study, treatment-naïve microfilaremic (>50 mf/mL, n = 32) and uninfected (circulating filarial antigen negative, n = 24) adults residing in Agboville district, Côte d’Ivoire, were treated with a single dose of IVM plus DEC plus ALB, and evaluated for adverse events (AEs) until 7 days post treatment. Drug levels were assessed by liquid chromatography and mass spectrometry. Persons responsible for assessing AEs were blinded to participants’ infection status.FindingsThere was no difference in AUC0-inf or Cmax between LF-infected and uninfected participants (P>0.05 for all comparisons). All subjects experienced mild AEs; 28% and 25% of infected and uninfected participants experienced grade 2 AEs, respectively. There were no severe or serious adverse events. Only fever (16 of 32 versus 4 of 24, PConclusionsModerate to heavy W. bancrofti infection did not affect PK parameters for IVM, DEC or ALB following a single co-administered dose of these drugs compared to uninfected individuals. The drugs were well tolerated. This study confirmed the efficacy of the triple-drug therapy for clearing W. bancrofti Mf and has added important information to support the use of this regimen in LF elimination programs in areas of Africa without co-endemic onchocerciasis or loiasis.Trial registrationClinicalTrials.gov NCT02845713.</div

Contamination du lait caillé et de l’oeuf consommé en Côte d’Ivoire par des pesticides organochlorés

La présente étude vise à évaluer l’aspect sanitaire de l’alimentation humaine à travers deux produits à forte consommation en Côte d’Ivoire : le lait caillé et l’oeuf. Ainsi, 30 échantillons de lait caillé ont été achetés et 30 échantillons d’oeufs de poulet ont été collectés dans trois fermes dans la ville d’Abidjan. Ces échantillons ont été traités dans le but de déterminer les résidus de 12 POC (Pesticides OrganoChlorés). Les analyses ont été réalisées au CG sur colonne capillaire avec un détecteur à capture d'électrons. Les résultats observés révèlent une contamination du lait caillé et de l’oeuf par 5 POC. Ainsi, des charges moyennes en μg/kg des isomères hexachlorocyclohexane (HCH) allant de 0,125 à 0,997 et de 1,870 à 35,907, de l’endosulfan allant de 0,045 à 0,563 et non détecté, de la dieldrine allant de 0,025 à 0,263 et de 5,727 à 69,710 et du Dichlorodiphenyltrichloroethane (DDT) et métabolites allant de 0,133 à 0,813 et de 21,105 à 75,22, ont été respectivement déterminées dans le lait caillé et dans l’oeuf. La teneur résiduelle moyenne des isomères HCH, des cyclodiènes (dieldrine, et endosulfane) et du DDT et ses métabolites constituent respectivement 40%, 40% et 20% de la moyenne du total des POC mesurés dans le lait caillé et respectivement 20%, 20% et 60% de celle mesurée dans l’oeuf.Mots-clés: pesticides organochlorés, lait caillé, oeuf, Côte d’Ivoire. Contamination of the curdled milk and the egg consumed in Ivory Coast by organochlorinated pesticides This study aims to determine the levels of organochlorinated pesticides (OCPs) in the curdled milk and egg. Thus, 30 samples of curdled milk were purchased and 30 egg samples were collected from three farms in the area of the lagoons. These samples were processed in order to determine the residues 12 OCPs. Analyses were performed by GC capillary column with electron capture detector. The observed results indicate contamination of curdled milk and egg by 5 OCPs. Thus, average loads in μg/kg of hexachlorocyclohexane (HCH) isomers ranging from 0.125 to 0.997 and 1.870 to 35.907, endosulfan ranging from 0.045 to 0.563 and undetected, dieldrin ranging from 0.025 to 0.263 and 5.727 to 69.710 and dichlorodiphenyltrichloroethane (DDT) and metabolites ranging from 0.133 to 0.813 and 21, 105 to 75.22, respectively, were determined in the curdled milk and egg. The average residual HCH isomers, cyclodiene (dieldrin and endosulfan) and DDT and its metabolites is respectively 40%, 40% and 20% of the average total OCPs measured in curdled milk and respectively 20%, 20 % and 60% of that measured in the bud.Keywords: organochlorinated pesticides, curdled milk, egg, Ivory Coast

Investigation of rodent reservoirs of emerging pathogens in Côte d'Ivoire, West Africa

Background: One of the main health problems in West Africa remains upsurge of emerging pathogens. Ebola virus disease outbreak occurred in 2014 in Liberia, Guinea and Sierra Leone, Monkeypox virus in Nigeria in 2017 and most recently Lassa virus in Nigeria, Togo and Benin in 2018.&nbsp; These pathogens have animal reservoirs as vectors for transmission. Proper investigation of the pathogens in their rodent vectors could help&nbsp; reduce and manage their emergence and spread. Methodology: This study was conducted with an approval from the Côte d’Ivoire Bioethics Community. Small mammal trappings were carried out in&nbsp; 9 sites within three zones namely, peri-urban, peri-rural and protected areas. Liver, lung and kidney tissues from trapped small mammals were&nbsp; sampled in accordance with the recommended conditions of biosafety and bioethics. The organs were transported in liquid nitrogen to the&nbsp; laboratory. Molecular tests were used to detect pathogens. Orthopoxviruses and Monkeypox virus were detected in the organs by PCR using&nbsp; consensus primers targeting the virus surface membrane haemagglutinin (HA) genes, while Leptospira species were detected by PCR using primers&nbsp; targeting the rrs and lfb1 genes. Results: Out of 4930 night-traps, 256 (5.19%) small mammals were trapped including Crocidura, Rattus, Lophuromys, Praomys, Mus and Mastomys.&nbsp; Leptospira species were detected in 6 genera from 7 study sites and the infected small mammals accounted for 13.3%. Leptospira sp was detected&nbsp; mainly in the rodent vector genera Rattus (32.3%), Lophuromys (29.0%), and Praomys (16.1%). Three species of Leptospira were detected and&nbsp; Leptospira interrogans was the most common frequent species (74.2%). Monkeypox virus was not detected from studied small mammals. Conclusion: The initial data from our investigation indicates the presence of Leptospira sp in rodent vectors, Rattus, Lophuromys and Praomys,&nbsp; which are the potential small mammalian reservoirs of this pathogen in Cote d’Ivoire

Molecular diagnostics by PCR of poxviruses (Orthopoxvirus (OPV) and Molluscum contagiosum virus (MCV)) in Cote d'Ivoire West Africa

The Orthopoxvirus (OPV) and the Molluscum contagiosum virus (MCV) are Poxviruses involved in viruses skin lesions in humans. OPV infects many vertebrates and MCV mainly infects humans. A diagnostic confusion is often observed between the clinical lesions due to the different Poxviruses firstly and secondly with other viruses like the virus of the chickenpox. In Côte d'Ivoire, the diagnosis of MCV remains essentially clinical and that of OPV is non-existent despite the risk of circulation of the virus. This study aims to implementthe molecular detection of the OPV and the MVC in Côte d'Ivoire. Material and method: Cowpoxvirus DNA and 21 DNA extracts from suspicious cutaneous lesions of the MCV were analyzed by conventional PCR. The consensus primers (EACP1, EACP2) designed from the surface hemagglutin gene were used for the detection of the OPVs and the primers (MCV1, MCV2) targeting the K fragment of the MCV were used for the MCV’s detection . A growing dilution series of the Cowpoxvirus DNA and the MCV allowed the study of the method’s sensitivity used. The DNAs of S.aureus, M. ulcerans, VZV, HSV, the Measles virus and Varicella virus were used for the specificity tests. Results: The detection of the OPV from the Cowpoxvirus viral strain was positive with a positivity threshold at 10-1 dilution. That of the MCV DNA from the suspected MCV's lesion was positive with a positivity threshold of up to 10 -6 dilution. No non-specific amplification was observed with the DNAs of the other pathogens responsible for lesions Cutaneous. The clinical diagnosis of the MCV was confirmed by PCR in 18 out of the 21 patients, ie 85.71%. On the 3 patients with a negative MCV PCR, 2 were positive for the OPV PCR , reflecting the risk of confusion between clinical lesions due to Poxviruses.Keyvords: Molecular diagnostic, Poxviruses, West Afric

Interrupting seasonal transmission of Schistosoma haematobium and control of soil-transmitted helminthiasis in northern and central Côte d’Ivoire: a SCORE study protocol

© The Author(s). 2018 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. The attached file is the published version of the article

Population genetic structure of Schistosoma haematobium and Schistosoma haematobium x Schistosoma bovis hybrids among school-aged children in Côte d'Ivoire

While population genetics of Schistosoma haematobium have been investigated in West Africa, only scant data are available from Cote d'Ivoire. The purpose of this study was to analyze both genetic variability and genetic structure among S. haematobium populations and to quantify the frequency of S. haematobium x S. bovis hybrids in school-aged children in different parts of Cote d'Ivoire. Urine samples were subjected to a filtration method and examined microscopically for Schistosoma eggs in four sites in the western and southern parts of Cote d'Ivoire. A total of 2692 miracidia were collected individually and stored on Whatman((R)) FTA cards. Of these, 2561 miracidia were successfully genotyped for species and hybrid identification using rapid diagnostic multiplex mitochondrial cox1 PCR and PCR Restriction Fragment Length Polymorphism (PCR-RFLP) analysis of the nuclear ITS2 region. From 2164 miracidia, 1966 (90.9%) were successfully genotyped using at least 10 nuclear microsatellite loci to investigate genetic diversity and population structure. Significant differences were found between sites in all genetic diversity indices and genotypic differentiation was observed between the site in the West and the three sites in the East. Analysis at the infrapopulation level revealed clustering of parasite genotypes within individual children, particularly in Duekoue (West) and Sikensi (East). Of the six possible cox1-ITS2 genetic profiles obtained from miracidia, S. bovis cox1 x S. haematobium ITS2 (42.0%) was the most commonly observed in the populations. We identified only 15 miracidia (0.7%) with an S. bovis cox1 x S. bovis ITS2 genotype. Our study provides new insights into the population genetics of S. haematobium and S. haematobium x S. bovis hybrids in humans in Cote d'Ivoire and we advocate for researching hybrid schistosomes in animals such as rodents and cattle in Cote d'Ivoire

Impact of different mass drug administration strategies for gaining and sustaining control of <i>Schistosoma mansoni</i> and <i>Schistosoma haematobium</i> infection in Africa

This report summarizes the design and outcomes of randomized controlled operational research trials performed by the Bill & Melinda Gates Foundation-funded Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) from 2009 to 2019. Their goal was to define the effectiveness and test the limitations of current WHO-recommended schistosomiasis control protocols by performing large-scale pragmatic trials to compare the impact of different schedules and coverage regimens of praziquantel mass drug administration (MDA). Although there were limitations to study designs and performance, analysis of their primary outcomes confirmed that all tested regimens of praziquantel MDA significantly reduced local; Schistosoma; infection prevalence and intensity among school-age children. Secondary analysis suggested that outcomes in locations receiving four annual rounds of MDA were better than those in communities that had treatment holiday years, in which no praziquantel MDA was given. Statistical significance of differences was obscured by a wider-than-expected variation in community-level responses to MDA, defining a persistent hot spot obstacle to MDA success. No MDA schedule led to elimination of infection, even in those communities that started at low prevalence of infection, and it is likely that programs aiming for elimination of transmission will need to add supplemental interventions (e.g., snail control, improvement in water, sanitation and hygiene, and behavior change interventions) to achieve that next stage of control. Recommendations for future implementation research, including exploration of the value of earlier program impact assessment combined with intensification of intervention in hot spot locations, are discussed