Variations spatio-temporelles du zooplancton d'un estuaire hyperhalin : la Casamance

La Casamance est un fleuve côtier du sud du Sénégal (Afrique de l'Ouest) pourvu d'une zone estuarienne relativement vaste. Le déficit pluviométrique de ces deux dernières décennies, combiné à une forte évaporation a contribué à une augmentation anormale de la salinité laquelle atteint 172 °/°° en amont, en fin de saison sèche 1986. La répartition spatio-temporelle du zooplancton semble dépendre de la température et de la salinité. Le zooplancton est abondant et diversifié (cinquante-six espèces adultes dont 55 % de copépodes et 13 types de larves; effectif pouvant atteindre 16500 individus/m3; indice de Shannon d'environ 3) tant que la salinité reste inférieure à 70 °/°°. En aval d'Adéane (93 km de l'embouchure), les salinités dépassent rarement cette valeur et les variations saisonnières du zooplancton suivent celles de la température (maximums en saison chaude de mars à novembre, et minimums en saison froide). En amont, la salinité, par l'amplitude de ses variations, devient le facteur prépondérant pour expliquer les variations spatio-temporelles du zooplancton,qui devient moint abondant et moins diversifié (6 à 18 espèces suivant les stations et les époques). (Résumé d'auteur

Profil épidémiologique et prise en charge de l’éclampsie au Sénégal: À propos de 62 cas

Introduction: L'objectif de cette étude etait d'apprécier les caractéristiques épidémiologiques et cliniques de l'éclampsie et d'évaluer la prise encharge et le pronostic maternel et périnatal.Méthodes: étude descriptive rétrospective sur 3 années (2007-2010) dans un service de Gynécologie Obstétrique de Dakar (Sénégal). Le critère d'inclusion était toute crise convulsive en période gravido-puerpérale dans un contexte de prééclampsie.Résultats: sur un total de 4587 accouchements, 62 cas d'éclampsie  étaient enregistrés représentant une incidence de 1,35%. Le profil retrouvéétait celui d'une jeune femme (24 ans), primipare (58.1%), habitant la  banlieue dakaroise (83.8%), porteuse d'une grossesse à terme (56.5%),mal suivie (82.3%) et référée par un poste de santé environnant (82.3%). La crise était survenue en antépartum et en post-partum dans 72.5 et 27,5% respectivement. Toutes les patientes présentaient une HTA ;  l''dème et la protéinurie étaient retrouvés dans 72.5 et 84%  respectivement. La majorité des patientes (88%) avait présenté plus de deux crises et l'état de mal éclamptique concernait 14.5% des cas. Le sulfate de magnésium était utilisé chez toutes les patientes. La césarienne était le mode d'accouchement largement adopté (75.5%) pour les  patientes reçues en antépartum. Le pronostic maternel était marqué par un cas de décès. La mortalité périnatale était de 130%. Conclusion: L'éclampsie est un problème de santé publique dans les pays en développement. Les principaux facteurs de risque sont la primiparité et l'âge jeûne. L'administration du sulfate de magnésium et la césarienne permettent d'améliorer le pronostic maternel et foetal. La prévention  passe nécessairement par un suivi prénatal de qualité

Water stress induces overexpression of superoxide dismutases that contribute to the protection of cowpea plants against oxidative stress

Water stress is known to induce active oxygen species in plants. The accumulation of these harmful species must be prevented by plants as rapidly as possible to maintain growth and productivity. The aim of this study was to determine the effect of water stress on superoxide dismutase isozymes (SOD, EC 1.15.1.1.) in two cowpea cultivars [Vigna unguiculata L. Walp., cv. Bambey 21 (B21) and cv. TN88-63]. Plants were submitted to water stress by withholding water supply and the expression of SOD was characterized during stress induction. In the same time, photosynthesis characteristics were determinedthrough the measurement of the quantum yield of PS II photochemistry and the energy absorption rate per reaction centre. Results show how water stress regulates the synthesis and the activity of superoxide dismutase isoforms and how these enzymes contribute to protect photosynthesis against the damageable effects of superoxide radicals in cowpea. Increased MnSOD and FeSOD activity and concentration were shown to be induced by water stress and associated with protection of photosystem II photochemistry and whole plant growth against oxidative stress in these plants. On the contrary, plants unable to express high MnSOD and/or FeSOD isoforms showed more sensitivity to water stress

Epidemiology of snakebites in Kedougou region (eastern Senegal) : comparison of various methods for assessment of incidence and mortality

Background: Although considered a public health issue in Senegal, the actual incidence and mortality from snakebite are not known. In the present study, an epidemiological survey was carried out in Kedougou region, southeastern Senegal, where envenomations, particularly by Echisocellatus, are frequent and severe. Methods: Three sources of data were used: records from health centers and reports by health professionals; traditional healers; and household surveys. Results: The annual incidence and mortality provided by health centers were 24.4 envenomations and 0.24 deaths per 100,000 population, respectively. The annual incidence recorded by traditional healers was 250 bites per 100,000 inhabitants, but the number of deaths was unknown. Finally, the household surveys reported an annual incidence of 92.8 bites per 100,000 inhabitants and an annual mortality rate of 2.2 deaths per 100,000 inhabitants. The differences in incidence and mortality between the different methods were explained by significant bias, resulting in particular from the complex patient's healthcare-seeking behavior. The incidence provided by health records should be used to specify the immediate quantitative requirements of antivenoms and places where they should be available first. Conclusion: Mandatory reporting of cases would improve the management of envenomation by simplifying epidemiological surveys. Patients' preference for traditional medicine should prompt health authorities to urge traditional healers to refer patients to health centers according to defined clinical criteria (mainly edema and bleeding or neurotoxic symptoms). Finally, household surveys were likely to reflect the actual epidemiological situation. Poison Control Center of Senegal should continue its work to sensitize stakeholders and train health staff

Absence of Helicobacter pylori in the oral cavity of 10 non-dyspeptic subjects demonstrated by real-time polymerase chain reaction

Helicobacter pylori plays a significant role in gastric disease. However, the presence of this bacterium in the oral cavity remains controversial. The aim of the present study was to detect and quantify H. pylori in 29 different sites of the oral cavity in non-dyspeptic subjects by means of real-time polymerase chain reactions (PCR). Ten subjects without gastric symptoms were studied. Samples from unstimulated saliva, three sites of the tongue, oral mucosa, and 12 sites of both supragingival and subgingival plaque were collected from each subject. DNA was extracted from the oral samples and analysed for the presence of H. pylori by real-time PCR (LightCycler) using JW23/22 primers which targeted the 16S rRNA gene. DNA from H. pylori DSM 4867 was used as a positive control. Amplification efficiency for the LightCycler 2.0 runs ranged from 1.8 to 2.4. Melting curve analysis identified all the positive control capillaries, which contained H. pylori reference DNA, as a single and narrow peak at a melting temperature between 84.5 and 84.9 degrees C. All the negative control capillaries with no template control and the 29 oral samples from each subject showed either no melting peaks or broad melting peaks below 80 degrees C, which were considered as primer dimers. Therefore, H. pylori was not detected from any of the 290 oral samples. As a conclusion, H. pylori seems not to be permanently present in the oral cavity of a non-dyspeptic population