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Background: The environment plays an important role in the dissemination of multidrug resistant bacteria, especially through the aquatic ecosystem, which is made up of liquid hospital effluents, rivers, but also spring water and drinking water. This study aims to determinate resistomes in some aquatic matrices in southern Benin.Methods: These samples were filtered through a membrane 0.22 µm thick. After filtration, the membrane was deposited on Muëller Hinton agar. Then the colonies resulting from this subculture were subjected to a microbiological examination by the conventional method. The antibiotic sensitivity test was carried out by the Kirby Bauer method according to the recommendations of the French Society of Microbiology. Resistance genes were looked for by standard PCR and the PCR products were used for agarose gel electrophoresis.Results: Of the 222 water samples collected, 265 bacterial strains were isolated, the majority of which were strains of Coagulase Negative Staphylococcus (CNS) with 37.74% (n = 100), followed by strains of Klebsiella pneumoniae (21.89%; n = 58), Escherichia coli (10.57%; n = 28). All isolated gram-negative bacilli strains are multidrug resistant with resistance of all strains to amoxicillin, ampicillin and amoxicillin + clavulanic acid. Of the 15 resistance genes sought in the genome of Gram-negative bacilli strains, only 8 were detected, namely the TEM, SHV, CTX-M15, VIM, NDM, SUL1, SUL2 and AADA genes. Strong resistance of CNS strains to amoxicillin, oxacillin and cefoxitin was observed. The Mec A gene was detected in all CNS strains. While the Van A and Van B genes were only detected in strains isolated from drinking water in sachets collected from producers and street sellers.Conclusion: These results show the dissemination of resistance genes in the aquatic ecosystem of Benin and once again confirms the urgency of a global fight against antimicrobial resistance.

To establish a baseline data on the susceptibility data to various insecticides for Anopheles gambiae sensu lato prior to the implementation of insecticide residual spray in the district of Copargo, Northern Benin, a study was conducted from June to December 2017 for this purpose. Adult females from field aged 2-5 days were subjected to insecticide- impregnated papers (permethrin 0.75%, delthamethrin 0.05%, DDT 4%, and bendiocarb 0.1%) following WHOPES. The species within An. gambiae complex, and the presence of knock down (kdr) and acetylcholinesterase (ace-1) mutations were searched from the An. gambiae populations subjected to the susceptible test. Results from this study showed that An. gambiae from Copargo district developed strong resistance to DDT (4% of mortality), permethrin (19%) and deltamethrin (43%) but were fully susceptible (mortality 100%) to bendiocarb. The PCRs showed the presence of two sub-species of An. gambiae, namely An. coluzzii, and An. arabiensis, with a predominance for An. coluzzii (77%). The kdr mutation was detected in all An. gambiae populations tested in very high frequency (> 95%) whereas the Ace-1 mutation was found at a very low frequency (< 2%). This study has shown that An. coluzzii is the most abundant specie found in the district of Copargo. The improper manner of the use of insecticide in this district for pests control exerted a huge pressure on mosquito larval population and contributed to the selection of pyrethroids resistance in An. gambiae s.l populations. The low frequency of Ace-1 mutation found in An. gambiae populations could lead the use of bendiocarb as a potential alternative against pyrethroid resistant An. gambiae for Insecticide Residual Spray activities.Keywords: Resistance; species; insecticide, Anopheles gambiae; Copargo; Benin. Etablissement de donnees de base sur la sensibilite de Anopheles Gambiae sensu lato vis-a-vis des insecticides en vue de la mise en place des strategies de pulverisations intradomiciliaires d’insecticides dans la commune de Copargo, nord- Bénin Dans le cadre de la mise en place des stratégies de pulvérisations intra domiciliaires d’insecticides pour lutter contre les vecteurs du paludisme dans la commune de Corpago au Nord-Est du Bénin, une étude sur la sensibilité des moustiques vis-à-vis des insecticides utilisés dans cette localité a été conduite de juin à décembre 2017. Les femelles adultes âgées de 2-5 jours ont été mises en contact des papiers insecticides (perméthrine 0,75%, deltaméthrine 0,05%, DDT 4% et bendiocarb 0,1%) suivant le protocole de l’Organisation Mondiale de la Santé. Les espèces du complexe Anopheles gambiae et les mutations knock down resistance (kdr) et acethylcholinestarase (ace-1) ont été recherchées au sein des populations de moustiques testés. Il ressort des travaux que les populations de An. gambiae ont développé une forte résistance vis-à-vis du DDT (4% de la mortalité), de la perméthrine (19%) et de la deltaméthrine (43%), mais restent entièrement susceptibles au bendiocarb. La PCR espèce a montré la présence de deux sous-espèces de An. gambiae: An. coluzzii et An. arabiensis, avec une prédominance de la sous espèce An. coluzzii (77%). La mutation kdr a été détectée chez toutes les populations de An. gambiae (> 95%), tandis que la mutation ace-1 a été retrouvée à une fréquence très faible (

Background: Biotic and abiotic factors have been reported to affect the larvicidal efficacy of Bacillus thuringiensis israelensis (Bti) and Bacillus sphaericus (Bs), although the extent to which they are affected has been poorly documented. This paper studies the effect of sunlight exposure on the efficacy of a new larvicide formulation based on both Bti and Bs, herein after referred to as BTBSWAX, applied against two different larval stages. Methods: The emergence of inhibition exhibited by BTBSWAX at three different dosages (1 g/m(2), 1.5 g/m(2), and 2 g/m(2)) was monitored under semi-field conditions using a total of 32 containers comprising 16 that were covered and 16 that were uncovered. Two experiments were conducted using first- and second-instar larvae of Anopheles gambiae, respectively. Results: BTBSWAX at 2 g/m(2) in covered containers exhibited high emergence inhibition (>80%) when larvae were exposed from 1st instar on day-6 post-treatment, whereas the emergence inhibition was only 28% in uncovered containers. For larvae exposed from 1st instar on day-12 post-treatment, the emergence inhibition was moderate (70%) in covered containers but was low (

L’émergence de la résistance aux antipaludiques était associée á l’accroissement dramatique de la mortalité due au paludisme dans certaines régions endémiques. Au Bénin, le paludisme est primairement causé par Plasmodium falciparum, l’une des espèces qui infectent l’homme. Le changement dans la politique de contrôle et de traitement du paludisme survenu courant 2005 - 2008, doit affecter aussi la recrudescence de la résistance aux antipaludiques retirés á l’utilisation dans le groupe cible. Dans la présente étude, les mutations conférant la résistance á certains antipaludiques ont été détectées et leur prévalence déterminée au sein d’une cohorte de 80 enfants vivant au Bénin, et souffrant du paludisme. Grâce á la PCR et au RFLP, nous avons déterminé les codons polymorphiques des gènes de la Dihydrofolate réductase (pfdhfr), codons 51, 59, et 108, de l’hydroptérase (pfdhps), codons 437, 540 associés á la résistance aux sulfadoxine et pyriméthamine, puis les gènes transporteur de résistance á la chloroquine (pfcrt), et de résistance multiple aux médicaments (pfmdr1), codons 76 et 86 de la résistance á la chloroquine. Pris individuellement, les taux de mutations étaient élevés, par exemple, codons pfcrt 76 ou pfdhfr 108, mais les combinaisons de mutations représentatives des résistances aux antipaludiques sont plutôt faibles, 33.75% pour la chloroquine, 9.25% pour la pyriméthamine et 6,5% pour la sulfadoxine. Nous concluons que les résistances aux antipaludiques étaient plus faibles et pouvaient décroitre davantage avec le maintien des mesures.Mots clés: Paludisme, mutations de résistance, PCR, RFLPEnglish AbstractThe emergence and spread of drug resistance in malaria has been associated with a dramatic increase in malaria mortality in some endemic regions. In Benin, malaria is primarily caused by Plasmodium falciparum, one of the species that infect humans. The change in malaria control strategies, although with remarkable results, has not stop resistance to some drugs that were used before the change in drug policy happened 2005 - 2008 in Benin. The present study was conducted to assess the prevalence of mutations involved in resistance to some anti-malaria drugs among 80 symptomatic children undergoing malaria episodes in Benin. Using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) assays, we assessed polymorphic codons on the plasmodium falciparum dihydrofolate reductase (pfdhfr) gene (51, 59, 108) and dihydropterase (pfdhps) gene (437, 540) associated with resistance to sulfadoxinepyrimethamine, and the chloroquine resistance transporter (pfcrt) gene (76), and multidrug resistance (pfmdr1) gene (86), mutations conferring chloroquine resistance. Although mutations were high at single gene codon levels, e.g. Pfcrt 76 or pfdhfr 108, combined resistance mutations were low, 33.75% for chloroquine, 9.25% for pyriméthamine and 6,5% for sulfadoxine résisitance. We conclude that drug resistance genes were lower that before and speculate that it will continue decreasing at least in this population to zero as control measures will be maintained.Keywords: malaria, drug resistance, PCR, RFLP

The aim of this study was to investigate the antibacterial activity of aqueous, ethanol, ethyl acetate and dichloromethane extracts of two different cashew tree parts (leaf and bark). The susceptibility of strains to the different extracts was evaluated in vitro by disc diffusion method on ten reference strains and nine foods strains. The minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) were determined respectively by macro-dilution method and seeding on solid medium. Among the four types of extracts, only the ethanol and ethyl acetate extracts of the two organs inhibited the growth of both bacteria and yeast. The MIC varies respectively between 0.039 and 0.625 mg/ml for reference strains and from 0.078 to 2.5 mg/ml for food isolated strains. Concerning MBC, it varies from 0.313 to 20 mg/ml for food isolated strains and from 0.078 to 20 mg/ml for reference strains. The ethanol and acetyl acetate extracts of the two cashew organs displays both a bacteriostatic and bactericidal effects on tested microorganisms. Our results suggest that extracts from cashew leaves may provide novel precursors for antimicrobial drug development research. Key words: Antibacterial activity, Anacardium occidentale L., Staphylococcus, Benin.

© 2015 Vodounon CA, et al.Background: We know, through recent studies, the existence of some morpho-biochemical peculiarities in the process of type 1 programmed death of patients' lymphocytes suffering from bronchial asthma, but little convincing data exist on the activity of enzymes involved in this physiological process. Therefore, the aim of our research was to study the enzymatic activity of secreting granules of patients' lymphocytes with bronchial asthma, according to the degree of severity. Method: The study was based on the role of granular extracts in the process of programmed death isolated lymphocytes from peripheral blood of relatively healthy individuals and asthmatic patients with different severity. The immunological characteristics of lymphocytes was done with the radial immune-diffusion method and ELISA test but the method of agarose gel electrophoresis help us to detect the catalytic activity of protein extracts of secreting granules of lymphocytes. Results: The results obtained showed that lymphocytes from asthmatic patients with severe severity are characterized by a decrease in cytotoxic T lymphocytes content balanced by an increase in T-Helper lymphocytes. We also noticed the enzymatic activity at all the groups studied but this activity was relatively high in asthmatics with severe severity. Furthermore, the study of the cationic dependence has allowed to establish an increase in enzymatic activity in all the groups studied after incubation of DNA in a medium containing Ca2+ with a pH of 7.5 unlike ions Mn2+ which seem to reduce the enzymatic activity. The expression of enzymatic activity in the presence of zinc allows us to suggest the presence of DNase acid in granules, which activity is not necessarily associated with divalent metal ions. Conclusion: Based on the above results, one might conclude that the secreting granules have a high enzymatic activity but with a strong cationic dependence. This not only allows a better understanding of the morphological changes observed during the course of apoptosis in lymphocytes of patients but also brings more to the knowledge of the enzymatic influence in the process of type 1 programmed death.

© 2015 Asian Network for Scientific. Bronchial Asthma is considered as the most spreading human chronic diseases. The diagnostic of the disease at its beginning is very difficult because the light forms of the disease can’t be diagnosed as the symptoms are not very well developed at the outbreak of the disease. The objective of this study was to correlate the climatic and geographic factors and the environmental conditions in the occurrence of Atopic Bronchial Asthma and other autoimmune phenomena, for example the prevalence of abzymes in the pathogenesis of Atopic Bronchial Asthma. In the present work, enzyme linked to immune sorbent assay method and the methods of electrophoresis in agarose gel were used. The results of our study showed the discovery of an excessive auto-antibodies to DNA in the blood vessels of patients with atopic bronchial asthma and there was a direct correlation dependence (r = 0.0005) between the level of auto-antibodies to DNA and the severity of the Atopic Bronchial Asthma. The detected auto-antibodies possess catalytic activity of DNA, enzymatic specificity which is associated with the degree of severity of disease. The auto antibodies in patients suffering from severe forms of Bronchial Asthma are specific for monofilament DNA and antibodies in the blood serum of the patients with the light form of asthma is heterogenic: besides antibodies with monofilament substratum, some specific antibodies with bi-filament DNA circulate. Therefore, in the serum of the patients suffering from Atopic Bronchial Asthma antibodies with Catalytic activity DNA was observed-that is abzymes. It was suggested that these “abzymes” maybe directly involved in the removal of debris produced by the metabolism of organism under physiological conditions. Considering all these facts, Abzymes can be regarded as serological markers of autoimmunity and needs to be tested while investigating autoimmunity especially in Atopic Bronchial Asthma and it may also serve as an additional criterion for the diagnosis of asthma even in the early stages and can also help in the evaluation of the effectiveness of the treatment.

The emergence of various diseases specifically severe diseases such as bronchial asthma is associated with apoptosis of lymphocytes. One of the major biochemical features of apoptosis is chromosome DNA fragmentation implemented by apoptotic nucleases. The inactivation of these apoptotic nucleases produces undigested DNA and is linked to a number of autoimmune disorders. Instead of this we have studied the enzymatic activities of the cytoplasmic and nucleic proteins of lymphocytes from healthy donors and patients with bronchial asthma. The study of enzymatic activities of the nuclease of lymphocytes was assessed by flow cytometry, spectrofluorimetiy and electrophoresis method in agarose gel. In the peripheral blood cells of healthy donors undergoing apoptosis, we found a DNAse activated by Ca2+ and Mg2+ ions. Lymphocytes of patients with bronchial asthma contain DNAses, the activity of which depends on the seriousness of the desease. In patients cells, the activity of the Mn2+-dependent DNAse increases, whereas the activity of the Ca2+, Mg2+-dependent DNase decreases. Taking into consideration the role of the Ca2+, Mg2+-dependent DNAse in apoptosis, we can propose that there is a link between the reduction of the rate of apoptosis of lymphocytes in patients with bronchial asthma and the dysfunction of the induction of "apoptotical" Ca2+, Mg2+-dependent nuclease. According to the results obtained, we can assume that why apoptosis of lymphocytes resist in patients with bronchial asthma is a reduction in concentration of endocellular calcium and an increase of manganese ions content, which results in the triggering of activation mechanism for Mn2+-dependent endonuclease activity. This leads to the change of DNA fragmentation nature in lymphocytes and as a consequence, to disorders in process of apoptotic bodies' formation, thus, hindering apoptosis of lymphocytes in patients with bronchial asthma. © 2013 Asian Network for Scientific Information.

Foods poisoning due to microbial toxins are widespread throughout the world. These foods poisoning are prevalent in African countries were street alimentation enable 80% of urban populations to feedthemselves easily and at lower price. The street foods constitute a major public health problem because of the multiplicity and the diversity of bacteria they can transport. So, the aim of our study was to assess the microbial quality of some street foods collected among the vendors in Cotonou city. The investigations on the selling sites and the analysis showed that there is perpetual risk of food contamination. Themajority of the vendors (84%) are women, and 78.67 % are illiterates. The microbiological analysis revealed that 77% of pathogenic bacteria were found among the ambulant vendors, 33% among semistationaryvendors and 26 among stationary vendors. All the concerned meals had a high charge of microbes indicating faecal pollution, of staphylococcal, salmonella and some yeast and mildew. However, considering the role of this kind of alimentation in African national economies, it is importantto find strategies leading a sanitary security, by epidemiologic surveillance of diseases transmitted by street foods. Les intoxications alimentaires dues à l’ingestion de toxines microbiennes sont répandues à travers le monde. Ces intoxications alimentaires sont très fréquentes dans les pays africains où l’alimentation de rue permet à plus de 80% des populations urbaines de s’alimenter facilement et à moindre coût. Les aliments vendus aux abords des rues de nos villes constituent donc un problème de majeure de santé publique de par la multiplicité et la diversité de la flore microbienne qu’ils véhiculent. Ainsi, notre étude a eu pour butd’étudier les possibilités de contamination de quelques aliments de rue prélevés chez des vendeurs dans la ville de Cotonou au Bénin. Les investigations sur les lieux de vente et les résultats d’analysemicrobiologique ont révélé la présence d’un risque perpétuel de contamination selon les types de distributeurs. La majorité (84%) des vendeurs était des femmes et 78,67% étaient illettrés. Les analysesmicrobiologiques ont montré que les aliments qui ne nécessitent pas de cuisson lors de la préparation avaient les plus fortes charges microbiennes. Soixante dix sept pour cent (77%) des germes pathogènes ont été détectés dans les aliments prélevés chez les vendeurs ambulants, 33% chez les semi-fixes et 26% chez les Fixes. Tous les plats incriminés ont des charges microbiennes en flore aérobie mésophile, indicateurs de pollution fécale, de staphylocoques et quelques levures et moisissures. Toutefois vu le rôle que joue cette alimentation dans les économies nationales de nos pays africains il est important de mettre en place plusieurs stratégies visant à une sécurité sanitaire par une surveillance épidémiologique des maladies transmises par les aliments de rue.