Détermination Des Teneurs En Mercure (HG) Total Chez La Moule Perna Perna Et L’oursin Echinometra Lucunter De La Baie De Soumbédioune (Sénégal) Et Évaluation Des Risques Sanitaires

La baie de Soumbédioune où s’effectue une importante activité de cueillette et de commercialisation de fruits de mer, constitue le réceptacle d’énormes quantités d’eaux usées et de déchets provenant du canal 4 et des activités artisanales qui s’y effectuent. C’est dans ce contexte qu’une étude visant à déterminer le niveau de contamination par le mercure des moules (Perna perna) et des oursins (Echinometra lucunter) et à évaluer les risques sanitaires liés à consommation de ces produits a été réalisée. Elle a consisté à collecter des échantillons (crus et transformés) de ces deux espèces durant les périodes d’abondance et de non-abondance en 2018. L’analyseur direct de mercure DMA-80 a été utilisé pour déterminer teneurs en mercure contenues dans ces espèces. Les résultats obtenus après analyses montrent la présence de ce métal très toxique dans les parties comestibles de ces espèces mais à des concentrations en deçà de la norme établie par l’agence américaine pour la protection de l’environnement. Ces concentrations varient entre 0,0172 et 0,0475 mg.kg-1 pour les moules contre 0,0153 et 0,0274 mg.kg-1 pour les oursins. Les indices de risque sanitaire obtenus (oscillant entre 0,070 et 0,844) sont inférieurs à 1 révèlent que la consommation de ces espèces reste pour le moment sans danger. Néanmoins, elles devraient être consommées modérément en raison de la capacité du mercure à se bioaccumuler dans les organismes. Soumbedioune Bay, marked by an intense activity of exploitation and marketing of seafood, is the receptacle of huge quantities of wastewater from channel 4 and artisanal activities which are carried out there. That’s why a study aiming to determine the level of mercury contamination of mussels (Perna perna) and sea urchins (Echinometra lucunter) and to assess the health risks associated with their consumption was performed. It consisted to collect samples (non-transformed and transformed products) of these two species during the periods of abundance and non-abundance in 2018. The direct mercury analyzer DMA-80 was used to determine the mercury contents contained in these species. The results obtained after analyzes show the presence of this very toxic metal in the edible parts of these species but at concentrations below the standard established by the American agency for the protection of the environment. These concentrations vary between 0.0172 and 0.0475 mg.kg-1 for mussels against 0.0153 and 0.0274 mg.kg-1 for sea urchins. The health risk indices obtained (oscillating between 0.070 and 0.844) less than 1 reveal that the consumption of these species remains safe for the moment. However, they should be consumed moderately due to the ability of mercury to bioaccumulate in organisms

Étude comparative des peuplements ichtyologiques de l’Aire Marine Protégée de Joal-Fadiouth et des pêcheries des zones du pourtour non protégées à l’exploitation halieutique

L'effondrement des stocks de poisson est dû à la surexploitation des peuplements ichtyologiques consécutifs aux mauvaises pratiques de pêche au Sénégal. Cette situation a amené les écologistes marins et les gestionnaires de l'environnement à réévaluer les méthodes traditionnelles de gestion des ressources halieutiques. Pour connaitre la dynamique des peuplements ichtyologiques, nous avons mené une étude comparative des peuplements ichtyologiques de l’Aire Marine Protégée de Jaol-Fadiouth et des pêcheries des zones non protégées à l’exploitation halieutique durant la saison froide 2015. Ainsi, l’exploitation des données de pêches expérimentales réalisées au niveau de 16 stations dans les deux zones a permis de faire l’étude. L’analyse des paramètres environnementaux relevés sur chaque station montre que la zone de l’aire marine protégée est similaire à celle des zones non protégées à l’exploitation halieutique. Par conséquent, les éventuelles différences de peuplement ne s'expliquent pas par la variabilité des paramètres physicochimiques. L’analyse de paramètres physico-chimiques, des indicateurs de biodiversité à savoir : la richesse spécifique, les indices de diversité de Shannon-Weaver et d’équitabilité Pielou ont permis de déterminer les caractéristiques environnementales, la composition et la nature des peuplements, d'évaluer l'impact des mesures de gestion des différentes zones.   The collapse of fish stocks is due to the overexploitation of fish populations as a result of poor fishing practices in Senegal. This situation has led marine ecologists and environmental managers to re-evaluate traditional methods of managing fishery resources. In order to know the dynamics of the ichthyological populations, we conducted a comparative study of the ichthyological populations of the Jaol-Fadiouth Marine Protected Area and the fisheries of the areas not protected from fishing during the 2015 cold season. Thus, the exploitation of data from experimental fisheries carried out at 16 stations in the two areas allowed the study to be carried out. The analysis of the environmental parameters recorded at each station shows that the area of the marine protected area is similar to that of the areas not protected from fisheries exploitation. Therefore, any differences in population size cannot be explained by the variability of physico-chemical parameters. The analysis of physico-chemical parameters, biodiversity indicators such as species richness, the Shannon-Weaver diversity index and the Pielou equitability index allowed us to determine the environmental characteristics, the composition and the nature of the populations, and to evaluate the impact of the management measures of the different areas

In vitro vasorelaxation mechanisms of bioactive compounds extracted from Hibiscus sabdariffa on rat thoracic aorta

<p>Abstract</p> <p>Background</p> <p>In this study, we suggested characterizing the vasodilator effects and the phytochemical characteristics of a plant with food usage also used in traditional treatment of arterial high blood pressure in Senegal.</p> <p>Methods</p> <p>Vascular effects of crude extract of dried and powdered calyces of <it>Hibiscus sabdariffa </it>were evaluated on isolated thoracic aorta of male Wistar rats on organ chambers. The crude extract was also enriched by liquid-liquid extraction. The various cyclohexane, dichloromethane, ethyl acetate, butanol extracts obtained as well as the residual marc were subjected to Sephadex LH-20 column chromatography. The different methanolic eluate fractions were then analyzed by Thin Layer (TLC) and High Performance Liquid Chromatography (HPLC) and their vascular effects also evaluated.</p> <p>Results</p> <p>The H. Sabdariffa crude extract induced mainly endothelium-dependent relaxant effects. The endothelium-dependent relaxations result from NOS activation and those who not dependent to endothelium from activation of smooth muscle potassium channels. The phytochemical analysis revealed the presence of phenolic acids in the ethyl acetate extract and anthocyans in the butanolic extract. The biological efficiency of the various studied extracts, in term of vasorelaxant capacity, showed that: Butanol extract > Crude extract > Residual marc > Ethyl acetate extract. These results suggest that the strong activity of the butanolic extract is essentially due to the presence of anthocyans found in its fractions 43-67.</p> <p>Conclusion</p> <p>These results demonstrate the vasodilator potential of <it>hibiscus sabdariffa </it>and contribute to his valuation as therapeutic alternative.</p

Study of the woody flora in the mining areas of the commune of Sabodala (Kédougou, Senegal)

Le Sénégal oriental est une région très riche de par sa flore, sa faune mais également de par son sous-sol qui renferme d’intéressants indices ou gisements d’or, d’uranium, de fer, de cuivre, de nickel, de lithium, de marbre, de molybdène et de chrome. Cette exploitation n’est toutefois pas sans conséquences car les activités extractives causent d’énormes préjudices notamment à l’environnement. La présente étude se fixe comme objectif d’établir la situation de référence de la flore ligneuse de la zone. Ainsi à partir d’un échantillonnage de type aléatoire stratifié et d’un maillage systématique, l’étude de la flore du site a été faite en utilisant la méthode de l’inventaire itinérant. La flore de la zone d’exploitation minière de la commune de Sabodala et ses environs est riche de 103 espèces distribuées dans 75 genres et 32 familles. Les Fabaceae, Combretaceae et Malvaceae sont les familles majoritaires de cette flore. Le genre Combretum est le plus riche avec 7 espèces. Le spectre biologique montre une prédominance des microphanérophytes et des mésophanérophytes. Les espèces de l’élément-base soudanien sont majoritaires avec 35,3 %, indiquant le caractère soudanien de la zone. Ces résultats sont très importants dans les processus de reconstitution de la flore de la zone. Mots-clés: flore ligneuse, Goumbati-Kobokoto, savanes, zone soudanienneEastern Senegal is a very rich region for its flora and fauna but also for its subsoil which contains interesting gold, uranium, iron, copper, copper, nickel, lithium, marble, molybdenum and chromium deposits. However, this exploitation is not without consequences, as mining activities cause enormous damage, particularly to the environment. The objective of this study is to establish the reference situation of the woody flora of the area. Thus, using stratified random sampling and a systematic grid, the study of the site's flora was carried out using the mobile inventory method. The flora of the mining area of the commune of Sabodala and its surroundings is rich in 103 species distributed in 75 genera and 32 families. The Fabaceae, Combretaceae and Malvaceae are the majority families of this flora. The Combretum genus is the richest with 7 species. The biological spectrum shows a predominance of microphanerophytes and mesophanerophytes. The species of the Sudanian base element are the majority with 35.3%, indicating the Sudanian character of the area. These results are very important in the processes of reconstitution of the flora of the zone. Keywords: woody flora, Goumbati-Kobokoto, savannas, Sudanian zon

Right-heart infective endocarditis: apropos of 10 cases

The prevalence and characteristics of right heart endocarditis in Africa are not well known. The aim of this study was to describe the epidemiological, clinical and laboratory profiles of patients with right-heart infective endocarditis. This was a 10-year retrospective study conducted in 2 cardiology departments in Dakar, Senegal. All patients who met the diagnosis of right heart infective endocarditis according to the Duke's criteria were included. We studied the epidemiological, clinical as well as their laboratory profiles. There were 10 cases of right-heart infective endocarditis representing 3.04% of cases of infective endocarditis. There was a valvulopathy in 3 patients, an atrial septal defect in 1 patient, parturiency in 2 patients and the presence of a pacemaker in one patient. Anaemia was present in 9 patients whilst leukocytosis in 6 patients. The port of entry was found to be oral in three cases, ENT in one case and urogenital in two cases. Apart from one patient with vegetations in the tricuspid and pulmonary valves, the rest had localized vegetation only at the tricuspid valve. However, blood culture was positive in only three patients. There was a favorable outcome after antibiotic treatment in 4 patients with others having complications; three cases of renal impairment, two cases of heart failure and one case of pulmonary embolism. There was one mortality. Right heart infective endocarditis is rare but associated with potentially fatal complications.Pan African Medical Journal 2015; 2

Characterization of element and mineral content in Artemisia annua and Camellia sinensis leaves by handheld X-ray fluorescence

Tea infusion is the most frequently worldwide consumed beverage next to water, with about 20 billion cups consumed daily. Artemisia annua leaves contain comparable levels of nutrients and mineral elements (dry matter basis) to many marketed tea (Camellia sinensis) leading us to suspect that this crop could also serve as an alternative source of nutrients for humans. Analyzer moveable X-ray fluorescence is used to evaluate the content of major, minor and toxic elements in A. annua from two different countries compared to six marketed tea in Senegal. To ensure qualified results, certified reference materials were used to perform the calibration. The very low and often negligible levels of inherent elements in the leaves, which are far below recommended toxic levels, establishes A. annua and selected marketed tea as a good reservoir of elements that might favour its use as a potential herbal tonic by humans. The mineral elements are present in different kinds of herbal leaves in various proportions depending on soil composition and the climate in which the plant grows.Keywords: X-ray fluorescence (XRF), Artemisia annua, Camellia sinensis, elements, leaves, medicinal plantAfrican Journal of Biotechnology Vol. 12(26), pp. 4179-418

Reproductive biology of largescaled mullet, Parachelon grandisquamis (Actinopterygii: Mugiliformes: Mugilidae), in the Marine Protected Area of Niamone–Kalounayes (Casamance estuary, Senegal)

In Senegal, studies on the family Mugilidae are rare and little data is available on their reproductive biology. This study, carried out in the MPA of Niamone–Kalounayes (Casamance River estuary, Senegal) aims to enhance our knowledge of the reproductive biology of the largescale mullet, Parachelon grandisquamis (Valenciennes, 1836), a species highly prized by the local population as a food source. To better understand its reproductive biology, a series of monthly samplings over twelve (12) months from July 2021 to June 2022 was carried out. Experimental fisheries were carried out at six (6) stations located in secondary channels lined with mangroves, using a seine net (250 m long and 25 mm mesh side). A total of 361 individuals were sampled, including 321 female specimens and 40 male specimens. The calculated sex ratio was in favor of females (1:8), with a significant difference between the calculated sex ratio and the theoretical 1:1 sex ratio (χ2 = 218.73; P-value &amp;lt; 0.05). In the MPA of Niamone–Kalounayes, the breeding period of P. grandisquamis extends from March to July, from the end of the dry season up to the beginning of the wet season. The sizes at first sexual maturity were 17 cm in males and 18 cm in females, showing that in the MPA of Niamone–Kalounayes, males and females of P. grandisquamis reach sexual maturity at very close sizes (χ2 = 0.02; P &amp;gt; 0.05). As this species is subject to the intense fishery by many actors in the area, these findings may be proven useful in the process of developing a management plan for this particular species

Contribution to the Study of the Size Structure, the Length-Weight Relationship, the Condition Factor and the Sex-ration of Shrimp Farfantepenaeus notialis (Pérez Farfante, 1967) in the Estuary of Sine-Saloum (Senegal)

This study was carried out within the context of USAID/COMFISH project for establihing a biological data base for some fish species including shrimp Farfantepenaeus notialis to support management plans for these species. This study on Farfantepenaeus notialis in the Sine-Saloum estuary revealed that the sampled individuals are relatively small sizes.The average cephalothoracic sizes are less than 20 mm at Bettenty (male = 18.0 ± 2.9; female=18.5 ± 3.9) and at Foundiougne (male = 17.6 ± 2.9; female = 18.5 ± 3.8). The allometric rate «b» is more important at Bettenty (b = 2.94) than at Foundiougne (b = 2.75) and condition factor K is higher during the hot season in both locations (Bettenty: K = 0.80 in hot season; K = 0.78 in cold season; Foundiougne: K = 0.82 in hot season, K = 0.75 in cold season). The sex ratio of Farfantepenaeus notialis is in favor of females at Bettenty (54.6%) and at Foundiougne (51.2%). The size classes show that below 15 mm and beyond 20 mm, the number of female is higher than that of male. Beween 15 to 20 mm, male are higher.

Les pointes-ondes continues du sommeil: Aspects electro-encephalographiques au service de neurologie du Centre Hospitalier National Universitaire de Fann de Dakar

Introduction: Les pointes-ondes continues du sommeil, constituent une entité électroencéphalographique peu fréquente, mais au pronostic&nbsp; neuropsychologique potentiellement péjoratif.Objectif: L‘objectif de ce travail était de déterminer les aspects électroencéphalographiques chez des patients présentant des pointes-ondes continues du sommeil.Patients Et Methode: Nous avons réalisé une étude rétrospective descriptive sur 2 ans à la Clinique&nbsp; Neurologique du Centre Hospitalier National Universitaire de Fann à Dakar, portant sur des dossiers&nbsp; électroencéphalographiques d‘enfants présentant des pointes-ondes continues du sommeil. Les données&nbsp; personnelles, les caractéristiques de l‘activité électroencéphalographique de veille et de sommeil ont été recueillies.Resultats: Soixante-trois dossiers ont été colligés, soit une fréquence de 1,02% de la population globale et de 2,60% de la population d‘enfants. Le sex-ratio était de 1,42, l‘âge moyen de 6,65 +/- 2,63 ans. Les indications prédominantes étaient les crises généralisées tonico-cloniques et les crises focales motrices. Presque tous (96,97%) les enregistrements de veille comportaient des anomalies paroxystiques, à prédominance hémisphérique gauche le plus souvent et dans les régions péri-sylviennes. Environ 2 enfants sur 3 (63,49%) avaient des altérations des figures physiologiques du sommeil. Les pointes-ondes prédominaient au stade II du sommeil, légèrement dans l‘hémisphère gauche, plus fréquemment dans les régions péri-sylviennes. Le schéma de pointes-ondes continues du sommeil antérieures prédominait. L‘index de pointes-ondes variait entre 50 et 100%.Conclusion: Le diagnostic des pointes-ondes continues du sommeil doit être précoce. La précision des caractéristiques topographiques permet le diagnostic de déficits cognitifs latents, d‘où l‘intérêt des études de corrélation clinicoélectrique. &nbsp; English Title: Continuous spike-waves during slow sleep: electroencephalographic aspects in the neurological department of Fann National University Hospital of Daka

Djehuty : a mixed-initiative handwriting game for preschoolers

Learning to read and write is a fundamental right and a necessary skill for the personal, cultural, and economic development of people and their societies. However, children of developing countries, such as sub-Saharan areas, are currently at a greater risk of illiteracy. The current penetration of mobile technologies and the internet in sub-Saharan rural areas, however, offers a unique opportunity for tackling the challenge of literacy at a large scale. Motivated by the current shortage of preschool teachers for training handwriting in a personalised manner, this paper discusses the design of Djehuty, an educational gamified environment for preschoolers. Djehuty is equipped with an artificial intelligence module which generates a style of handwriting and suggests handwriting paths to the child in a mixed-initiative manner. The paper presents the key elements of the game prototype.peer-reviewe