523 research outputs found
Étude de la toxicité aiguë et subchronique de l’extrait aqueux de Passiflora foetida Linn. (Passifloraceae) chez les rats et les souris
Cette étude été réalisée dans le but d’évaluer la toxicité aiguë et subchronique de Passiflora foetida chez les rats et les souris. Pour l’étude de la toxicité aiguë, les animaux de chaque espèce répartis en 8 lots de 10 chacun (5 mâles et 5 femelles) ont reçu des doses uniques allant de 60 à 180 mg/kg (souris) ou de 40 à 160 mg/kg (rats) de poids corporel (P.C) de l’extrait aqueux de Passiflora foetida (EAPF) et du NaCl 9‰ (témoins) par voie intraperitonéale (i.p.). Ensuite, 6 autres lots de 10 souris (5 mâles et 5 femelles) ont été traités oralement avec des doses de 2000 à 13000 mg/kg et du NaCl 9‰ (témoins). Les comportements des animaux ont été observés après chaque traitement. Dans l’étude de la toxicité subchronique, 4 lots de 6 rats (3 mâles et 3 femelles) ont été gavés quotidiennement pendant 28 jours avec des doses de 600, 800, 1200 mg/kg et du NaCl 9‰. Les résultats ont montré que les doses létales 50% (DL50) par voie i.p. étaient de 121,62 et 89,74 mg/kg de P.C respectivement chez les souris et les rats. En outre, la DL50 par voie orale chez les souris était supérieure à 13000 mg/kg de P.C. Les poids relatifs des organes (reins, foie, poumons, et coeur) prélevés chez les rats à la fin du traitement subchronique n’ont pas significativement varié. Les analyses hématologiques et biochimiques ont montré des réductions significatives du nombre d’hématies et de l’hématocrite à la dose de 1200 mg/kg d’une part et de l’ALT, de l’AST, du cholestérol à 800 et 1200 mg/kg d’autre part. L’étude histopathologique a révélé des cas d’apoptose cellulaire hépatique et de nécrose tubulaire des reins uniquement chez quelques animaux traités avec la plus forte dose. En conclusion, EAPF est toxique par voie i.p. et exerce une action hémolytique à forte dose. Cependant, il pourrait avoir des effets protecteurs sur le foie et le système cardiovasculaire.Mots clés: Apoptose, nécrose tubulaire, action hémolytique, système cardiovasculair
Study of the Root System of Local and Improved Sorghum Cultivars Grown in Mali
Roots play a fundamental role in plant growth by supplying water and mineral to the stem and
leaves. These underground organs are much less known than the aerial organs mainly due to the
difficult access to the root systems in soil. In spite of this, only a few studies were conducted on
roots. Given the importance of roots for plant growth, a better understanding of their functioning
may help solve some issues such as water stress that can affect the performance of the crops. A
total of 100 sorghum cultivars collected in the Sahelian zone of Mali an area receiving an annual
rainfall of 200 to 600 mm, were used in a root characterization study. The plant materials were
composed of 4 races and 5 intermediates sorghum races. Seeds of the entries were planted
directly in PVC tubes of 1m containing soil and arranged in completely randomized design with
three replications; in one planting date. Each tube was planted in a dugout ground to 50 cm deep.
The tubes were distant of 0.50 m within each row and 0.75 m between rows. The trial was watered
from the tap every two days until harvest. The results showed high variability among the varieties
studied for root length and root density, with a root length reaching over 1.00m. The study did not
identify any pattern in the root systems of the four races and their five intermediates races.
However, there was a positive correlation between root length and density indicating an increase in
root length correspond to an increased root density. The diversity found in the root system could be
a basis for improving root architecture in breeding populations and the evaluation of the behaviour
of the sorghum varieties with different root systems in water stress conditions
A randomised trial in Mali of the effectiveness of weekly iron supplements given by teachers on the haemoglobin concentrations of schoolchildren
Objective: To assess the effect on the haemoglobin concentrations of schoolchildren of weekly iron tablets administered by teachers.
Design: Sixty schools were randomly assigned to two groups: in 30 schools children were given weekly for 10 weeks a tablet providing 65 mg of iron and 0.25 mg of folic
acid; in the other 30 schools no iron tablets were given. All children were dewormed and given vitamin A before the study began. The haemoglobin concentration of up to
20 randomly selected children in each school was estimated before and 2 weeks after the end of treatment.
Setting: Rural community schools in Kolondieba district of Mali.
Subjects: Some 1113 schoolchildren aged 6-19 years with a mean of 11.4 years.
Results: The haemoglobin concentration of treated children rose on average by 1.8 g l -1 (P < 0.001) and the prevalence of anaemia fell by 8.2% (P < 0.001); in
untreated children the haemoglobin concentration fell by an average of 22.7 g l -1 (P < 0.001) and the prevalence of anaemia rose by 9.4% (P < 0:001). The fall in haemoglobin concentration among untreated girls of 24.0 g l21 was greater than in untreated boys (20.3 g l -1 (P < 0.001).
Conclusions: Weekly iron tablets given by teachers prevented a general fall in the haemoglobin concentrations of untreated children, and led to a small but statistically
significant rise among treated children (P < 0.001). Young children benefited more than children aged </=12 years, and girls benefited more than boys
Hepatitis B testing and treatment in HIV patients in The Gambia - compliance with international guidelines and clinical outcomes
Background Compliance with WHO guidelines on HBV screening and treatment in HIV-coinfected patients is often challenging in resource limited countries and has been poorly assessed in sub-Saharan Africa. Methods Between 2015 and 2016, we assessed physician’s compliance with WHO guidelines on HIV-HBV coinfection in the largest HIV clinic in The Gambia, and the hepatic outcomes in HIV-HBV coinfected patients as compared to randomly selected HIV-monoinfected controls. Results 870 HIV-infected patients regularly seen in this clinic agreed to participate in our study. Only 187 (21.5%, 95% CI 18.8–24.3) had previously been screened for HBsAg, 23 (12.3%, 95% CI 8.0–17.9) were positive of whom none had liver assessment and only 6 (26.1%) had received Tenofovir. Our HBV testing intervention was accepted by all participants and found 94/870 (10.8%, 95% CI 8.8–13.1) positive, 78 of whom underwent full liver assessment along with 40 HBsAg-negative controls. At the time of liver assessment, 61/78 (78.2%) HIV-HBV coinfected patients received ART with 7 (11.5%) on Tenofovir and 54 (88.5%) on Lamivudine alone. HIV-HBV coinfected patients had higher APRI score compared to controls (0.58 vs 0.42, p = 0.002). HBV DNA was detectable in 52/53 (98.1%) coinfected patients with 14/53 (26.4%) having HBV DNA >20,000 IU/L. 10/12 (83.3%) had at least one detectable 3TC-associated HBV resistance, which tended to be associated with increase in liver fibrosis after adjusting for age and sex (p = 0.05). Conclusions Compliance with HBV testing and treatment guidelines is poor in this Gambian HIV programme putting coinfected patients at risk of liver complications. However, the excellent uptake of HBV screening and linkage to care in our study suggests feasible improvements
Efficacite de l’hydroxyde de cuivre contre la nervation noire du chou (Brassica oleracea l.) Causee par la bacterie xanthomonas campestris pv. Campestris
Pour tester l’efficacité de l’hydroxyde de cuivre contre la nervation noire du chou, des expérimentations ont été conduites sur le site maraîcher de Houèto (commune d’Abomey-Calavi), au cours desgrande et petite saisons de pluies de l’année 2013. Le dispositif de bloc aléatoire complet dispersé à quatre répétitions et cinq traitements a été utilisé. Les parcelles témoins, traitées avec l’oxyde de cuivre 1 kg/ha et avec l’hydroxyde de cuivre aux doses de 2,25 kg/ha, 3 kg/ha et 4,5 kg/ha étaient les traitements à comparer. La sensibilité de Xanthomonas campestris pv. campestris (Xcc) à l’hydroxyde de cuivre, l’incidence et la sévérité de la nervation noire du chou étaient les paramètres évalués au cours des expérimentations. La bactérie Xcc a été positivement confirmée. Pendant la grande saison de pluies, la sévérité a été significativement faible dans les parcelles traitées avec l’hydroxyde de cuivre aux doses de 3 kg/ha (7,11 %) et 4,5 kg/ha (7,09 %). Par contre, en petite saison de pluies, la maladie s’était faiblement manifestée sur tout le site expérimental avec une sévérité inférieure à 0,05 %. L’incidence était aussi plus élevée au cours de la grande saison de pluies (79,6 % à 82,5 %) comparée à la petite saison de pluies (0,9 % à 1,6 %). Les doses de 3 kg/ha et 4,5 kg/ha d’hydroxyde de cuivre ont été les plus efficaces contre la nervation noire du chou.Mots clés : Nervation noire du chou, hydroxyde de cuivre, efficacité, Xanthomonas campestris pv. campestrisEnglish abstractEfficiency of copper hydroxide on cabbage (Brassica oleracea l.) Black rot caused by xanthomonas campestris pv. CampestrisTo test the efficiency of copper hydroxide against the cabbage black rot, trials were conducted on the garden site of Houeto village (Abomey-Calavi), during the big and the short rainy seasons in 2013. The randomized complete block design with four repetitions and five treatments have been used. Untreated control plot, plot treated with copper oxide at 1 kg/ha and plots treated with copper hydroxide at 2.25 kg/ha, 3 kg/ha and 4.5 kg/ha were the five considered treatments. The susceptibility of Xanthomonas campestris pv. campestris (Xcc) to the copper hydroxide, the incidence and the severity of cabbage black rot, were the evaluated parameters during the two trials. Xcc was positively confirmed. During the big rainy season, the severity was significantly low in plots treated with copper hydroxide at 3 kg/ha (7.11 %) and 4.5 kg/ha (7.09 %). While during the short rainy season, the disease was weak in the whole experimental site with a severity varying between 0.02 % and 0.03 %. The incidence was also high during the big rainy season (79.6 % to 82.5 %) and weak during to the short rainy season (0.9 % to 1.6 %). The doses of 3 kg/ha and 4.5 kg/ha of copper hydroxide were efficient on cabbage black rot.Key words : Cabbage black rot, copper hydroxide, efficiency, Xanthomonas campestris pv. campestri
Development and Utilisation of Improved WhiteSeeded, Tan-Plant Grain Sorghum Cultivars in Mali
The pedigree breeding method was successfully adopted to develop high yielding, white-seeded, grain sorghum cultivars with other attributes including “tan” plants, sensitivity to photoperiod and excellent adaptation to the Sudanian and Sahelian agro-ecological conditions in Mali. The new cultivars possess an excellent grain quality which added value for processing. The breeding process included crossing of local guinea race cultivars and improved or introduced Caudatum race varieties, selected from F2, F3, F4, F5 and F6 generations, conducting yield and grain quality trials of advanced lines on station and on-farm with farmer participatory selection. Processing quality of the grain was evaluated through measuring the decortication yield of each cultivar using the TADD (Tangential Abrasive Dehuller Device); measuring shelf life of processed flour in bags made of polyethylene for 3 months; manufacturing of new products by partially substituting wheat flour with flour of new sorghum varieties in pastry and biscuits. The study revealed a series of improved lines with "tan" plants, white grain, Guinea race type characterised by a loose panicle, long glumes and a hard grain. The best example of new cultivars N’Tenimissa, was described as the first white, “tan” plant, straw-coloured glume, photoperiod sensitive and high yielding sorghum cultivar with a white endosperm, and a thin pericarp developed in Mali. The cultivar has almost the same decortication yield with already adopted varieties by farmers. Its flour yield is similar to that of local guinea cultivars, and its flour is nearly as white as wheat flour. The analysis of various organoleptic parameters indicated that partially substituting wheat with 20% sorghum flour made the preferred biscuit by consumers prompting the commercial manufacturing of a biscuit called Deliken by the General Alimentation du Mali (GAM). A commercial sorghum supply chain was initiated by linking smallholders producing the new cultivar to a grain trader for selling the grain to the industry. This shows a path for the future in the diversification of uses of a local staple crop, sorghum. It is based on a strong Public-Private Partnership to link smallholders to the commercial supply chain, providing an incentive for farmers to grow new and highly productive cultivars for the development of value-added products
Possible alternative for national supply of seed potatoes (Solanum tuberosum L.) from in vitro culture at the Agro-physio-genetic and Plants Biotechnology laboratory of IPR / IFRA of Katibougou, Mali
The enhancement of the potential for reducing food insecurity and poverty through potato cultivation in Mali is largely limited by difficult access to quality seed. In trying to find ways to reduce these shortcomings outlined above that work has been done. The objective of this work was to assess the economic profitability of the local potato seed sourcing scheme from in vitro propagation and to analyze the competitiveness of the sourcing scheme from imported elite seed. The technical and economic feasibility of the local potato seed supply scheme was assessed at five levels. The first concerns the production of vitro-plants in the laboratory, the second the production of mini zero generation tubers (G0). Regarding the other three levels of evaluation, they were carried out in collaboration with the seed cooperatives by successive multiplication from mini-tubers to obtain seeds of one “G1”, two “G2” and three “G3” generations". The profitability of the procurement scheme from the elite imported and multiplied once seed was evaluated in order to analyze its competitiveness in relation to the local circuit. The valuation indicates positive profit margins. However, it should be noted that the economic efficiency coefficients of vitro-propagation (0.77) and tunnel multiplication (0.75) are less than 1. The production cost of one kilogram of G3 is equal to at 463.39 F CFA. A profit margin of 456.61 F CFA / kg emerges between this unit production cost and the selling price of imported seeds, which amounts on average to 920 F CFA / kg. The production of plants is technically feasible and profitable with a cost price of one kg of G3 in the order of 500 to 600 F CFA against 900 to 1000 F CFA / kg for imported seed.
La valorisation du potentiel de réduction de l’insécurité alimentaire et de la pauvreté à travers la culture de la pomme de terre au Mali est limitée en grande partie par l’accès difficile à la semence de qualité. En essayant de trouver des moyens pour réduire ces insuffisances soulignées ci-dessus que ce travail a été effectué. Le présent travail avait pour objectif d’évaluer la rentabilité économique du schéma d’approvisionnement locale en semences de pomme de terre à partir de la vitro propagation et d’analyser la compétitivité du schéma d’approvisionnement à partir de la semence élite importées. La faisabilité technico-économique du schéma d’approvisionnement local en semences de pomme de terre était évaluée à cinq niveaux. Le premier concerne la production de vitro-plants au laboratoire, le deuxième la production de mini tubercules de génération zéro (G0). Pour ce qui concerne les trois autres niveaux d’évaluation, ils ont été réalisés en collaboration avec les coopératives semencières par multiplications successives à partir de mini-tubercules pour obtenir des semences de génération une «G1», deux «G2» et trois «G3». La rentabilité, du schéma d’approvisionnement à partir de la semence élite importée et multipliée une fois, a été évaluée en vue d’analyser sa compétitivité en rapport avec le circuit local. L’évaluation indique des marges bénéficiaires positives. Cependant, il faut remarquer que les coefficients d’efficacité économiques de la vitro-propagation (0,77) et de la multiplication sous tunnels (0,75) sont inférieurs à 1. Le coût de production d’un kilogramme de G3 est égal à 463,39 F CFA. Une marge bénéficiaire de 456,61 F CFA / kg se dégage entre ce coût de production unitaire et le prix de vente des semences importées qui s’élève en moyenne à 920 F CFA / kg. La production de plants est techniquement faisable et rentable avec un coût de revient d’un kg de G3 de l’ordre de 500 à 600 F CFA contre 900 à 1 000 F CFA / kg pour la semence importée
Spatial distribution of the chromosomal forms of anopheles gambiae in Mali
<p>Abstract</p> <p>Background</p> <p>Maps of the distribution of malaria vectors are useful tools for stratification of malaria risk and for selective vector control strategies. Although the distribution of members of the <it>Anopheles gambiae </it>complex is well documented in Africa, a continuous map of the spatial distribution of the chromosomal forms of <it>An. gambiae s.s. </it>is not yet available at country level to support control efforts.</p> <p>Methods</p> <p>Bayesian geostatistical methods were used to produce continuous maps of the spatial distribution of the chromosomal forms of <it>An. gambiae s.s</it>. (Mopti, Bamako, Savanna and their hybrids/recombinants) based on their relative frequencies in relation to climatic and environmental factors in Mali.</p> <p>Results</p> <p>The maps clearly show that each chromosomal form favours a particular defined eco-climatic zone. The Mopti form prefers the dryer northern Savanna and Sahel and the flooded/irrigated areas of the inner delta of the Niger River. The Savanna form favours the Sudan savanna areas, particularly the South and South-Eastern parts of the country (Kayes and Sikasso regions). The Bamako form has a strong preference for specific environmental conditions and it is confined to the Sudan savanna areas around urban Bamako and the Western part of Sikasso region. The hybrids/recombinants favour the Western part of the country (Kayes region) bordering the Republic of Guinea Conakry.</p> <p>Conclusion</p> <p>The maps provide valuable information for selective vector control in Mali (insecticide resistance management) and may serve as a decision support tool for the basis for future malaria control strategies including genetically manipulated mosquitoes.</p
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