Acute and Sub-chronic (28-day) Oral Toxicity Studies of Hydroalcohol Leaf Extract of Ageratum conyzoides L (Asteraceae)

Purpose: Ageratum conyzoides is an annual herbaceous plant commonly used in African traditional medicine as a purgative, antipyretic, anti-ulcer and wound dressing agent. The objective of this study was to investigate the acute and sub-chronic toxicity of A. conyzoides leaves in Wistar rats. Methods: In the acute test, the limit test dose of 5000 mg/kg was administered to Wistar rats and then observed individually 1 h post-dosing, and at least once daily for 14 days. Sub-chronic toxicity was evaluated after administering daily oral doses of 500 and 1000 mg/kg body wt., for 28 days to the rats, Biochemical and haematological assessments as well as body and relative organ weights of the rats were carried out. Results: The limit dose of 5000 mg/kg did not cause any mortality or signs of acute toxicity in the rats tested during the observation period. In the sub-chronic tests, the results did not show any treatment–related abnormalities in terms of haematological and biochemical parameters. However, urea was significantly (p < 0.05) lower in the group treated with 500 mg/kg of A. conyzoides extract. The weekly body and organ weight of the rats showed no significant differences between the control and the rats treated with the extract except for liver where there was a significant increase (p < 0.05) in rats that received 1000 mg/kg, i.e., 3 ± 0.2 g as against 2.5 ± 0.1 g for the control. Conclusion: Our results suggest that the hydroalcohol extract of A. conyzoides is relatively safe when administered orally in rats.Keywords: Ageratum conyzoides, Acute and sub-chronic toxicity, Biochemical parameters, Haematological analysis, Wistar rats

Cetacean research in Senegal 1995-97, an overview. Scientific Committee document SC/49/SM10, International Whaling Commission, Bournemouth, UK

Historically Senegal is the West-African nation with the best kept faunistical records for cetaceans. We found verifiable evidence for at least 18 species, but limited life history data. Quantified information on interactions with soaring coastal fisheries is wanting. Here we present preliminary results of recent field work in central and central-south Senegal, which aim was to help design a long-term research plan with Senegalese scientists, offer training and reinitiate data collecting.With limited monitoring we encountered evidence of dolphin by-catches but no wide-spread directed dolphin fishery. However the presence of tell-tale conditions including spreading acceptance for consumption of dolphin meat and indications of overexploitation of some fish stocks are known warning signs. Future efforts should cover larger areas and generally be more intensive. Three carcasses of Atlantic hump-backed dolphin Sousa teuszii found on Sangomar island had rope tied around the tailstock. Fishermen at Djifer and Joal-Fadiouth confirmed regular incidental takes and landings. In the Siné-Saloum delta, inshore S. teuszii and T. truncatus are probably the most affected species. Senegal’s EEZ waters support large industrial fisheries which may constitute an additional source of by-caught small cetaceans. We here document 21 new specimen records and a series of sightings. Dolphins occurring in the Casamance river and upstream in the salt-water canals of the Saloum delta are identified as T. truncatus

Effet protecteur des feuilles de Opilia celtidifolia contre l’ulcère induit par l’éthanol chez le rat

Opilia celtidifolia est une plante traditionnellement utilisée contre les plaies et l’ulcère gastro duodénal. Le but de ce travail était d’étudier l’activité antiulcéreuse des extraits aqueux de cette de la plante. Des extraits aqueux, total et épuisé, ont été préparés par décoction. Le décoté total a été testé à 100 et 200 mg/kg et le décocté épuisé à100 mg/kg. Le Sucralfate a été utilisé comme témoin positif à la dose de 1000 mg/kg et le groupe non traité a reçu de l’eau distillée à10 ml/kg. Les extraits ont été administrés par voie intragastrique, une heure après, 0,5 ml d’éthanol à 90% a été administré aux animaux pour provoquer l’ulcère pendant une heure. Après ce temps, les rats ont été sacrifiés. L’estomac de chaque rat a été ouvert pour observer et compter les ulcères. L’indice d’ulcère a été exprimé et le pourcentage de protection a été calculé. A 100mg/kg, le décocté épuisé a induit une protection de la muqueuse de 75%, contre 31% pour le décocté total. Le Sucralfate, utilisé comme témoin a présenté une protection de 87,50%. Ces résultats démontrent que les feuilles de Opilia celtidifolia peuvent intervenir dans le traitement de l’ulcère gastrique. La mise au point d’un phytomédicament contre l’ulcère gastrique à base des feuilles de cette plante est donc envisageable.Mots clés : Opilia celtidifolia, protection, ulcère gastrique

Clinical features of the arterial hypertension in a medical emergency service in Abidjan

The authors studied the clinical features of high hypertension (blood pressure over 240 mmHg for the systolic and over 140 mmHg for the diastolic pressure) in 300 black African patients observed in the unit of medical emergency at Abidjan.In this unit arterial hypertension represented 8.27% of the cases and was the main cause of mortality (12.9 % VS 7.2 % for the others causes).The common complications were heart failure (29%), stroke (21 %), encephalopathy (19%) and renal failure (16%). Diabetes was associated in 8.33% of cases. The high rate of mortality is observed when there was stroke (25.4%) and renal fai lure (25%). There was significant increase in mortality linked to high blood pressure

The influence of the thickness of the Cds emitter layer on the performance of a CIGS solar cell with acceptor defects

In this work, we simulated a solar cell based on CIGS with simple default acceptor, using software (SCAPS) version 3.302 in order to study certain parameters. In particular, we have varied the thickness of the CdS emitter (0.05 mum, 0.04 mum and 0.03 mum) to study its influence on the performance of the cell. We were able to record that the energy efficiency increased from 16.50% for a thickness of 0.05 mum of the emitter to 16.87% for a thickness of 0.03 mum of the emitter. We also noted an improvement in other parameters, such as the form factor from FF = 79.81% to 80.10%, with the decrease in the thickness of the CdS. And from the Nyquist diagram, we also determined parameters like the series resistance to get an idea on the equivalent electrical circuit of the studied cell

Mobilité relative des métaux lourds issus de la décharge d’Akouédo et risque de contamination de la nappe du Continental Terminall (Abidjan - Côte d’Ivoire)

Relative mobility of heavy metals resulting from Akouédo landfill and assessment of Continental Terminal groundwater contamination risk(Abidjan-Côte d'Ivoire)The aim of this study is to know the geochemical mechanisms which control the vertical migration of heavy metals and to evaluate the risk of the Continental Terminal groundwater contamination resulting from Akouedo landfill. The chemical analyses of 56 samples showed that the soil of Akouedo landfill is rich in Cu (20-369.7 ppm), Fe (850-12500 ppm), Zn (18.6-1163.7 ppm), Pb (10.3-1450 ppm), Cd (1-11.5 ppm) and Cr (27.7-125ppm). Adsorption, principal geochemical mechanism in the soil, allows the retention of the majority of metals (Cu, Fe, Zn, Pb, Cd) on the organic matter (NTK and Corg) very abundant in the surface layers and on the clayed layers. But chromium is not much adsorbed and migrates more towards the deep layers. Cr is thus able to reach the groundwater easily and to cause a contamination of this one

Rift Valley fever outbreak, Mauritania, 1998: seroepidemiologic, virologic, entomologic, and zoologic investigations.

A Rift Valley fever outbreak occurred in Mauritania in 1998. Seroepidemiologic and virologic investigation showed active circulation of the Rift Valley fever virus, with 13 strains isolated, and 16% (range 1.5%-38%) immunoglobulin (Ig) M-positivity in sera from 90 humans and 343 animals (sheep, goats, camels, cattle, and donkeys). One human case was fatal