Génération de trajectoire aléatoire d’une cible de tir mobile

Cette étude a pour objet la conception du système de direction d’un véhicule automatique  de type automobile à trajectoire aléatoire (périodes et angles de rotation aléatoires), imprévisible dans le temps et l’espace. Le besoin a été exprimé par les Forces Armées et de Sécurité du Mali pour la formation des tireurs sur des cibles mobiles à trajectoire imprévisible. Le changement de direction est assuré par un moteur « pas-a-pas » actionnant les deux roues avant. Ce moteur est contrôlé par une carte électronique ARDUINO programmée pour générer des codes aléatoires de changement de direction et de pente de déviation. L’ensemble sera en mouvement entre deux murs parallèles. Le mouvement est rendu encore plus aléatoire par le changement de trajectoire induit automatiquement par le contact aléatoire de l’engin avec les parois des murs. Dans cet article, nous montrons les résultats obtenus par simulation informatique sans tenir compte du terrain et de la carrosserie qui pourront faire l’objet de publications ultérieure

Constitutive activation and accelerated maturation of peripheral blood t cells in healthy adults in burkina faso compared to Germany: The case of malaria?

<p>Abstract</p> <p>Objective</p> <p>It is not exactly known how frequent exposure to <it>Plasmodium falciparum </it>shapes the peripheral blood T-cell population in healthy West Africans.</p> <p>Methods</p> <p>The frequency of peripheral blood CD4⁺lymphocytes responding to <it>Plasmodium falciparum </it>merozoite surface protein 1 <it>(Pf</it>MSP-1) by production of interferon-gamma (IFN-γ), interleukin-2 (IL-2) or tumor necrosis factor-alpha (TNF-α) was determined using a commercially available flow cytometric activation assay (Fastlmmune) in 17 healthy adults in Nouna, Burkina Faso. T-cell activation and maturation in peripheral blood of healthy adults in Burkina Faso (n = 40) and Germany (n = 20) were compared using immunophenotyping and three-colour flow cytometry.</p> <p>Results</p> <p>Significant numbers of <it>Pf</it>MSV-1 -specific CD4⁺lymphocytes producing IFN-γ, IL-2 and/or TNF-α were detected in 14 healthy adults in Nouna. Cytokine profiles showed predominant production of IFN-γ and TNF-α. Compared to Germans, Burkinabé showed markedly lower proportions of CCR7⁺CD45RA⁺naïve CD4⁺cells and slightly higher frequencies of CD95⁺CD4⁺T-cells and of CD38⁺CD8⁺T-cells. The median antibody-binding capacity of CD95^dimCD4⁺T-cells in Burkinabé was more than twice the value observed in Germans (263 vs. 108 binding sites per cell, p < 0.0001).</p> <p>Conclusions</p> <p>We hypothesize that an IFN-γ-induced increase in the expression level of CD95 on CD4⁺lymphocytes may lower the activation threshold of resting naïve CD4⁺T-cells in healthy adults living in Burkina Faso. Bystander activation of these cells deserves further study as a molecular mechanism linking strong IFN-γ responses against <it>Plasmodium falciparum </it>to decreased susceptibility to parasitemia observed in specific ethnic groups in West Africa.</p

Effets de l’extrait aqueux de gomphrena celosioides (amaranthaceae) sur les enzymes hépatiques

Gomphrena celosioides est une plante utilisée en médecine traditionnelle dans le traitement des maladies hépatiques. Le tétrachlorure de carbone (CCl4) a été utilisé pour induire une hépato toxicité chez les rats. Ce hépatotoxique provoque une montée significative des taux des enzymes hépatiques et de la bilirubine. Les différents traitements avec l’extrait aqueux de Gomphrena celosioides (EAG) à la dose de 500 mg/kg de Poids Vif (PV) et de la silymarine (SIL) reconnue pour ses propriétés hépatotoxiques, à la dose de 300 mg/kg PV entrainent une baisse des taux de ces paramètres. Les traitements préventifs des animaux avec l’EAG et la SIL ont entraîné une baisse du taux des transaminases sériques, des phosphatases alcalines et de la bilirubine avec une protection de 65,06 % pour l’EAG et 78,34 % pour la SIL en ce qui concerne l’Alanine amino transférase (ALAT). Les traitements curatifs des animaux à l’EAG et à la SIL ont donné une protection de 56,35 % pour l’EAG contre 70,45% pour la SIL en ce qui concerne l’ALAT. L’activité hépato protectrice de l’EAG est donc plus protective que curative. Cette activité est comparable à celle de la SIL. Les mécanismes possibles de cette activité peuvent être dus à l’action des antioxydants contenus dans les flavonoïdes, présents dans l’EAG.Mots-clés : affections hépatiques, silymarine, médecine traditionnelle, hépato toxicité, flavonoïdes.The aqueous extract effect of Gomphrena celosioides in liver enzymes Gomphrena celosioides is a plant used in traditional medicine in the treatment of liver disease. Carbon tetrachloride (CCl4) was used to induce hepatotoxicity in rats. This hepatotoxic causes a significant rise in liver enzymes and bilirubin. The various treatments with the aqueous extract of Gomphrena celosioides (EAG) at a fixed dose of 500 mg/kg body weight (bw) and silymarin (SIL), which is known for its hepatoprotective properties, at a fixed dose of 300 mg/kg bw, decrease the activity of these parameters. Preventive treatments of animals with EAG and SIL resulted in a decrease in serum transaminases, alkaline phosphatase and bilirubin with the protection of 65, 06 % for EAG and 78, 34 % for SIL in Alanine Amino Transferase (ALT) respectively. With regards to ALT, curative treatments with EAG and SIL gave a protection of 56, 35 % for EAG against 70, and 45 % for SIL. The activity of EAG is more protective than curative. This activity is comparable to that of SIL. Possible mechanisms of this activity may be due to the action of antioxidants in flavonoids, whose presence is known in EAG.Keywords : liver disease, silymarin, traditional medicine, hepatotoxicity, flavonoids

Dynamics of antigenemia and transmission intensity of Wuchereria bancrofti following cessation of mass drug administration in a formerly highly endemic region of Mali

Background After seven annual rounds of mass drug administration (MDA) in six Malian villages highly endemic for Wuchereria bancrofti (overall prevalence rate of 42.7%), treatment was discontinued in 2008. Surveillance was performed over the ensuing 5 years to detect recrudescence. Methods Circulating filarial antigen (CFA) was measured using immunochromatographic card tests (ICT) and Og4C3 ELISA in 6–7 year-olds. Antibody to the W. bancrofti infective larval stage (L3) antigen, Wb123, was tested in the same population in 2012. Microfilaraemia was assessed in ICT-positive subjects. Anopheles gambiae complex specimens were collected monthly using human landing catch (HLC) and pyrethrum spray catch (PSC). Anopheles gambiae complex infection with W. bancrofti was determined by dissection and reverse transcriptase polymerase chain reaction (RT-PCR) of mosquito pools. Results Annual CFA prevalence rates using ICT in children increased over time from 0% (0/289) in 2009 to 2.7% (8/301) in 2011, 3.9% (11/285) in 2012 and 4.5% (14/309) in 2013 (trend χ 2  = 11.85, df =3, P = 0.0006). Wb123 antibody positivity rates in 2013 were similar to the CFA prevalence by ELISA (5/285). Although two W. bancrofti-infected Anopheles were observed by dissection among 12,951 mosquitoes collected by HLC, none had L3 larvae when tested by L3-specific RT-PCR. No positive pools were detected among the mosquitoes collected by pyrethrum spray catch. Whereas ICT in 6–7 year-olds was the major surveillance tool, ICT positivity was also assessed in older children and adults (8–65 years old). CFA prevalence decreased in this group from 4.9% (39/800) to 3.5% (28/795) and 2.8% (50/1,812) in 2009, 2011 and 2012, respectively (trend χ 2  = 7.361, df =2, P = 0.0067). Some ICT-positive individuals were microfilaraemic in 2009 [2.6% (1/39)] and 2011 [8.3% (3/36)], but none were positive in 2012 or 2013. Conclusion Although ICT rates in children increased over the 5-year surveillance period, the decrease in ICT prevalence in the older group suggests a reduction in transmission intensity. This was consistent with the failure to detect infective mosquitoes or microfilaraemia. The threshold of ICT positivity in children may need to be re-assessed and other adjunct surveillance tools considered

Antimicrobial susceptibility of extended-spectrum beta-lactamase producing Enterobacteriaceae causing urinary tract infections in Ouagadougou, Burkina Faso

Objective: To determine the frequency of extended-spectrum beta lactamase producing Enterobacteriaceae (ESBL) and other antibioticsresistant bacteria in urinary tract isolates.Study Design: prospective and experimental study.Methodology: Place and duration of study :YalgadoOuedraogo University Hospital Center, Charles De Gaulle Pediatric Hospital Center, Saint Camille Hospital and National Public Health Laboratory, Ouagadougou, from November 2014 to October 2015.AllEnterobacteriaceaestrains isolated from urinary samples of patients were identifiedusing API 20E chemical gallery (BioMerieux, France). All strains were subjected to an array of 14 antibiotics to study their drug susceptibility by using Kirby- Baeurdisk diffusion method. Detection of ESBL was carried out by double disk diffusion technique. Statistical analysis was performed by Microsoft Excel and Anova one-way GrapPad Prism version 5.01. Chi-square (χ2) test was used to determine significance. A p˂ 0.05was considered to be statistically significant.Results: A total of 324 isolates of Enterobacteriaceae were identified during the study period, including211(65%) E. coli, 75 (23%)Klebsiella spp., 18 (6%) Enterobacter spp., 11 (3%)Proteus spp., 5 (2%) Citrobacter spp., Serratia spp. 3 (1%).All the clinical isolates were susceptible to imipenem. Resistance to amikacinwas 14% (45/324); gentamicin 54% (175/324); tobramycin 58% (187/324); nalidixic acid 72% (234/324),ciprofloxacin 63% (204/324) and to cotrimoxazole 83% (269/324).The overall rate of the EBSL producing strains was 35% (114/324). Their susceptibility to antibiotics was (imipenem,amikacin, cefoxitin and fosfomycin) 100% (114/114), 93% (106/114), 74% (84/114) and 84% (96/114) respectively. ESBL positivity within individual organism group was highest inEscherichia coli 64% (73/324) followed byKlebsiellaspp. 28% (32/324), Enterobacterspp. 3% (4/324), Proteus spp. and Citrobacterspp. 2% (2/324).Conclusion: The results showeda high frequency of ESBL producing Enterobacteriaceae, especially Escherichia coli and Klebsiellaspp. The data points to theneed of routine detection and surveillance of ESBL producing bacteria in Burkina Faso.Keywords: Antimicrobial susceptibility, Enterobacteriaceae, Urine, Burkina Fas

Sélection participative des variétés de sorgho à l’aide d’essais multilocaux dans deux zones cibles

Variety development for sorghum requires multi-location testing for yielding ability. In West-Africa, where adaptation to specific zones of rainfall distribution is crucial for the success of a variety, these multi-location trials need to be conducted within any specific zone of adaptation. As most West-African countries lack sufficient research station capacity for this type of yield testing, we have developed a trial design and experiments with a sharing of roles and responsibilities between farmers, NGO's and researchers that allow for effective varietal differentiation in the target environment across a wide range of production conditions within a zone. The added advantage of farmer participation in this early stage of variety evaluation is that farmers also evaluate a wide range of other traits that are essential for making a variety a success

Key factors predicting suspected severe malaria case management and health outcomes: an operational study in the Democratic Republic of the Congo

BACKGROUND: Evidence suggests that pre-referral Rectal Artesunate (RAS) can be a life-saving intervention for severe malaria in remote settings in Africa. Recognition of danger signs indicative of severe malaria is critical for prompt and appropriate case management. METHODS: This was an observational study conducted in three Health Zones of the Democratic Republic of the Congo to determine the distribution of dangers signs for severe malaria and assess their impact on RAS use, referral completion, injectable treatment and ACT provision, and health outcomes including death. An individual-level analysis was carried out, using multilevel-mixed effects logistic regression models. Severely ill febrile children < 5 years seeking care from community-based healthcare providers were recruited into a patient surveillance system based on the presence of key danger signs. Clinical and case management data were collected comprehensively over a 28 days period. Treatment seeking was elicited and health outcomes assessed during 28 days home visits. RESULTS: Overall, 66.4% of patients had iCCM general danger signs. Age of 2-5 years and iCCM general danger signs predicted RAS use (aOR = 2.77, 95% CI 2.04-3.77). RAS administration positively affected referral completion (aOR = 0.63, 95% CI 0.44-0.92). After RAS rollout, 161 children died (case fatality ratio: 7.1%, 95% CI 6.1-8.2). RAS improved the health status of the children on Day 28 (aOR = 0.64, 95% CI 0.45-0.92) and there was a non-significant trend that mortality was higher in children not receiving RAS (aOR = 1.50, 95% CI 0.86-2.60). Full severe malaria treatment at the RHF including injectable anti-malarial and a course of ACT was highly protective against death (aOR = 0.26, 95% CI 0.09-0.79). CONCLUSIONS: The main findings point towards the fact that danger signs are reasonably well recognized by health provider at the primary care level, and that RAS could influence positively health outcomes of such severe disease episodes and death. Its effectiveness is hampered by the insufficient quality of care at RHF, especially the provision of a full course of ACT following parenteral treatment. These are simple but important findings that requires urgent action by the health system planners and implementers

Open access publication of public health research in African journals

There are many claims to the benefits of open access publishing in general and for Africa in particular. This study aimed to describe the characteristics of scholarly journals expected to publish articles on public health from a number of African countries. Using African Journals Online and African Index Medicus, 174 journals from 13 African countries were identified. The six countries above the group’s median gross domestic product (GDP) published 145 journals, while the seven countries at or below the median GDP published 29 journals. Two thirds of the journals were freely available to download, but only a third had a Creative Commons licence, and most were not indexed. Around half of the journals levied full article processing charges (APCs) – journals from countries at median GDP or below were less likely to charge APCs than those from countries above the median GDP. One of the key findings is that only a few journals were indexed, limiting the ability of potential readers to find the results of research performed in local settings. The results suggest a need to assist journals and researchers to make the work they publish more accessible to the audience who might want to use the results

Knowledge/Attitude/Practices of HPV & Cervical Cancer, Willingness to Participate in Vaccine Trial in Preparation for HIV & HPV Vaccine Trials in Mali

Oral Presentation from AIDS Vaccine 2012 Boston, MA, USA. 9-12 September 201

West Africa International Centers of Excellence for Malaria Research: Drug Resistance Patterns to Artemether-Lumefantrine in Senegal, Mali, and The Gambia.

In 2006, artemether-lumefantrine (AL) became the first-line treatment of uncomplicated malaria in Senegal, Mali, and the Gambia. To monitor its efficacy, between August 2011 and November 2014, children with uncomplicated Plasmodium falciparum malaria were treated with AL and followed up for 42 days. A total of 463 subjects were enrolled in three sites (246 in Senegal, 97 in Mali, and 120 in Gambia). No early treatment failure was observed and malaria infection cleared in all patients by day 3. Polymerase chain reaction (PCR)-adjusted adequate clinical and parasitological response (ACPR) was 100% in Mali, and the Gambia, and 98.8% in Senegal. However, without PCR adjustment, ACPR was 89.4% overall; 91.5% in Mali, 98.8% in Senegal, and 64.3% in the Gambia (the lower value in the Gambia attributed to poor compliance of the full antimalarial course). However, pfmdr1 mutations were prevalent in Senegal and a decrease in parasite sensitivity to artesunate and lumefantrine (as measured by ex vivo drug assay) was observed at all sites. Recrudescent parasites did not show Kelch 13 (K13) mutations and AL remains highly efficacious in these west African sites