Neglected Tropical Diseases Pathogen and Human Genetic Interaction in the Genomic Era: Opportunities for (Sub-Saharan) African Scientists to Get on Board

The worldwide prevalence of the neglected tropical diseases (NTD) shows the diseases are affecting more than 1 billion. The burden of the Neglected tropical diseases cost to developing, the burden of the diseases cost to developing economies billions of dollars every year. The genomic research in the last decades providing a full sequence (some currently in the sequencing pipeline) of genomes of many of the organisms including those which are responsible of neglected tropical diseases, may help in the management of such diseases. With the human genome being sequenced, the understanding of the genomic interaction between human and NTD pathogen enable scientists to develop new strategies to prevent and treat these devastating diseases. In this context of genomic era, African scientists may interestingly play an insider role in order to be part of the history of the elimination of these diseases. However, a critical mass of African scientists in genomic area constitutes the first step toward this long way in struggle against NTD. Although the challenge is enormous, it is very important to recognize that some African countries and institutions are fully committed to develop and strengthen African leadership in genomic area, while some are conspicuously absent from this debate. Joining African competences and leadership through collaborative activities and moving forward remains the next challenge to really impact the control and elimination of the NTD

Teneurs en tanins de 15 ligneux fourragers du Burkina Faso

Face au recul progressif du fourrage herbacé, le bétail des villages de Diarabakoko et de Dionona est contraint en saison sèche de s’alimenter plus de fourrage des ligneux. Mais les teneurs en facteurs antinutritionnels particulièrement en tanins condensés de certaines espèces ligneuses peuvent limiter la consommation de leurs fourrages. L’objectif de l’étude est de caractériser et quantifier les tanins contenus dans les feuilles et/ou fruits de 15 ligneux fourragers couramment appétés. Les tanins ont été quantifiés par spectrométrie d’absorption UV-Vis à la longueur d’onde de 760 nm. Les tanins condensés ont été identifiés dans 53,33% des espèces étudiées avec des teneurs significativement différentes (P ˂ 0,05). Les teneurs des feuilles et des fruits ont varié respectivement de 0,810 ± 0,041 à 7,102 ± 0,117 g EAT/100 g MS et de 3,016 ± 0,056 à 8,074 ± 0,042 g EAT/100 g MS. Les teneurs en tanins galliques des feuilles ont oscillé entre 0,214 ± 0,006 et 3,627 ± 0,072 g EAT/100 g MS et celles des fruits entre 2,153 ± 0,006 et 2,380 ± 0,039 g EAT/100 g MS. Le fourrage des espèces étudiées sauf les feuilles de Acacia sieberiana et les fruits de Cassia sieberiana peuvent contribuer à la supplémentation des ruminants. Les teneurs en tanins peuvent servir de critère de choix supplémentaire des ligneux fourragers en aménagement pastoral et en agroforesterie.Mots-clés: Burkina Faso, ligneux fourragers, métabolites secondaires, tanins, teneurs, facteurs antinutritionnels. Tannins content of 15 woody forages from Burkina FasoFacing the progressive decline of herbaceous forage, ruminant animals from the villages of Diarabakoko and Dionona are forced in the dry season to feed more browse forages. But the levels of anti-nutritional factors particularly condensed tannins of some browses species may limit their consumption. The objective of the study was to characterize and quantify the tannins in the leaves and/or fruits of 15 common woody forage palatable. Tannins have been quantified by spectrophotometry UV-Vis absorption at wavelength of 760 nm. Condensed tannins were identified in 53.33% of the species studied with significantly different levels (P ˂ 0.05). The contents of leaves and fruits ranged respectively 0.810 ± 0.041 to 7.102 ± 0.117 g TAE/100 g DM and 3,016 ± 0.056 to 8.074 ± 0.042 g TAE/100 g DM. The contents of gallic tannins in leaves varied between 0.214 ± 0.006 and 3.627 ± 0.072 g TAE/100 g DM and those in fruits were between 2.153 ± 0.006 and 2.380 ± 0.039 g TAE/100 g DM. Forage species studied except the leaves of Acacia sieberiana and fruits of Cassia sieberiana can contribute to the supplementation of ruminants. Tannins content can be used as a supplementary criterion for selection of tree fodder in pasture management and in agroforestry.Keywords: Burkina Faso, browses, secondary metabolites, tannins, content, anti-nutritional factors

Évaluation de la qualité de composts à base de biomasses feuillées de deux espèces agroforestières à Cassou, Centre-Ouest, Burkina Faso

Albizia lebbeck (L.) Benth. and Gliricidia sepium (Jacq.) Kunth ex Walp. are species of the leguminosae group which are promoted in agroforestry. This study aimed at assessing the quality of leafy biomass composts of these two species in order to use them as green manure. For this, composts based on leafy biomasses of Albizia lebbeck and Gliricidia sepium have been characterized. The phytotoxicity tests of the composts was carried out using a germination test of Zea mays (L) and Arachis hypogaea (L). The effect of composts on the growth of Adansonia digitata L. and Sclerocarya birrea (A.Rich.) Hochst. subsp. Also evaluated. Comparison of means tests and repeated measures ANOVA were used to compare types of composts. The results show that these composts were not toxic. The average carbon, nitrogen, pHe and C / N ratios of the composts of Albizia lebbeck and Gliricidia sepium were in accordance with international standards. The effect of Gliricidia sepium compost on the growth of Adansonia digitata and Sclerocarya birrea was better than that of Albizia lebbeck and cow dung (P <0.05). The compost from the leafy biomass of Gliricidia sepium is of very good quality while that of Albizia lebbeck is of fairly good quality. The biomasses of these two species therefore constitute good material for composting. These results can be used to improve crop production in agroforestry. Albizia lebbeck (L.) Benth. et Gliricidia sepium (Jacq.) Kunth ex Walp. sont des espèces de légumineuses promues dans l’agroforesterie. Cette étude visait à évaluer la qualité des composts de biomasses feuillées de ces deux espèces afin de les utiliser comme engrais verts. Pour cela des composts à base de biomasses feuillées de Albizia lebbeck, de Gliricidia sepium ont été caractérisés. La phyto-toxicité des composts a été évaluée à l’aide d’un test de germination de Zea mays (L) et Arachis hypogaea (L). L’effet des composts sur la croissance de Adansonia digitata L. et Sclerocarya birrea (A.Rich.) Hochst.subsp. a également été évalué. Des tests de comparaisons de moyennes et une ANOVA à mesures répétées ont permis de comparer les types de composts. Les résultats montrent que les composts évalués n’étaient pas toxiques. Les teneurs moyennes en carbone, en azote, les pHe et les rapports C/N des composts de Albizia lebbeck et de Gliricidia sepium étaient conformes aux normes internationales. L’effet du compost de biomasse de Gliricidia sepium sur la croissance de Adansonia digitata et de Sclerocarya birrea était mieux que celui de Albizia lebbeck et la bouse de vache (P< 0,05). Le compost de biomasses feuillées de Gliricidia sepium est de très bonne qualité tandis que celui de Albizia lebbeck est d’assez bonne qualité. Les biomasses de ces deux légumineuses constituent donc un bon matériel pour le compostage. Ces résultats peuvent servir à améliorer la production végétale en agroforesterie

Spatial Dynamics And Risks Analysis Of Lowlands Degradation Potential Around Of Nakanbé-Dem Sub-Watershed In Center-Nord Of Burkina Faso (West Africa): Through Multi-Date Study And Satellite Tele-Analysis

Watershed degradation is a key issue for environmental change in the Sahel region and causes an unprecedented threat to the lowlands watershed and the livelihood of local people. This study analyzes the spatial dynamics and degradation risks of Nakanbé-Dem sub-watershed lowlands’potential. The study combines lowlands plants species assessment and digital processing. Lowlands spatio-temporal dynamics were assayed from landsat images of 1986, 1996, 2006 and 2016. Vegetation data and soil physical and chemical parameters allowed to characterize lowlands degradation states. Lowlands degradation risk assessment is based on flora analysis and remote sensing indices (Normalized Difference Vegetation Index, Normalized Difference Water Index, slope values and water accumulation zones). Spatio-temporal dynamics analysis between 1986 and 2016 showed a continuous degradation of Nakanbé-Dem lowlands potential. The coverage of farming land increased from 31 to 51% compared to the total lowland potential of 43320 ha. The riparian formations have decreased by 4.11% in the same period. As concerns the lowland beds, their coverage rate has continuously decreased from 24% in 1986 to 7.79% in 2016. The coverage rate of water bodies has not kept a linear evolution. It went from 2.27 to 2.62%, a slight increase of 0.35%. Soil and flora samples were taken from the three lowland geomorphological subunits: glacis, hillside and the central zone. Soil analyze concerned the following parameters: useful watercontent, saturation rate, carbon, nitrogen, potassium and bulk density. Flora parameters analyzed are: woody cover, density of regeneration individuals, tree density, quadratic diameter, tree height, ligneous plants species richness, herbaceous species richness. These different measurements have been taken on the glacis, hillside and central zone. Flora and soils analysis showed difference in lowlands topographic structures. Unlike hillside and glacis, their central zone is less degraded. It is characterized by an average specific richness of woody plants about 3.43% against 3.13 % for hillsides and 2. 44 % for glacis. Tree average density (129.29 in/ha), the number of trees large diameter (118. 55 in/ha) and woody cover (61.79 %) are higher in the central zone than on the hillsides and glacis. From Pedological aspects, central zone is characterized by a concentration great of organic matter (1.49%) (great rate of carbon and nitrogen) against 0.89 for glacis and 0.90 for hillsides. The useful water content (19.75 %) and the saturation rate (64.85) in the central zone are great. These values are low on the glacis (9.36 and 63,77) and hillsides (12.17 and 59.66).In the current context of persistent climatic pressure, the conquering of new farms will accelerate the growth of cropped acreages and increase the degradation risk of lowlands’ potential. Lowlands’ dynamic apprehension can serve as a basis of development and endogenous programs implementation to restore sub-watershed lowland’ potential

Contribution à l’étude de l’influence des paramètres d’élaboration et optimisation du procédé de mise en oeuvre de bio-composites en coques de cotonnier et polystyrène recyclé

L’élaboration d’un éco-matériau requière outre la caractérisation physico-chimique des matières premières utilisées, la maîtrise des paramètres du procédé de mise en oeuvre utilisés. Le présent travail est consacré à l’étude de l’influence des paramètres d’élaboration d’un biocompositeinjecté en coques de cotonnier et polystyrène recyclé, en vue d’optimiser le procédé de mise en œuvre et les propriétés du produit fini.Dans la démarche d’élaboration adoptée, deux procédés sont retenus:il s’agit del’extrusion,qui estutilisée pour l’élaboration ducompoundetde l’injection-moulage (des granulats issus de l’extrusion), utilisée pour fabriquerles éprouvettes et les produits finis. L’objectif visé est d’identifier les valeurs optimales des paramètres de mise en œuvredeces deux procédés en vue de l’élaboration des produits de qualité ayant notamment les propriétés mécaniques requisespour des applications diverses.Ainsi,après identification des paramètres optimisés de mise en œuvre, des éprouvettes ont été produites avec ces paramètres optimisés d’élaboration et leurs propriétés mécaniques tellesque:le module d’élasticité (E) ou module de Young, la contrainteà la rupture (σr),Le module d’élasticité en torsion ou module de cisaillement (G), les contraintes de traction,La résistance à l’impact du matériau appelée encore résilience (R),déterminéspar les essais de caractérisation et le meilleur matériau élaboré,identifié.Les résultats obtenus sont consignés dans le présent document à travers les courbes, tableaux et figuresqui suivent.Mots-clés: extrusion, injection, polystyrène recyclé/coques de cotonnier, paramètres d’élaboration. Contribution to the study of the influence of parameters to formulation and optimization of process implementation of bio-composite at cottonhulls and recycled polystyreneThe development of an eco-material requires further physico-chemical characterization of raw materials, control parameters of processof implementation used. This work is devoted to the study of the influence of processing parameters of a biocomposite injected cottonhullsand recycled polystyrene, in order to optimize the process of implementation and the properties of the finalproduct.In the development process adopted, two methods are used: this is extrusion, which is used for the preparation of the compound and injection molding (aggregates from extrusion),which isused for fabricate specimens and finalproducts.The objective is to identify the optimal parameter values for the implementation of these two methods for the development of quality products including having the required mechanical properties for various applications.Thus, after identification of optimized parameters forimplementation, test pieces were produced with the optimized parametersand mechanical properties as: the modulus of elasticity (E) or Young's modulus, the breaking stress (σr) the torsional spring or shear modulus (G),tensile stresses, the impact resistance of the material, also called resilience (R), determined by testing and characterization of the material produced better identified. The results obtained are reported in this paper through the curves, tables and figures that follow.Keywords: extrusion, injection, recycled polystyrene / cotton hulls, seed processing parameters

Typologie spatiale de la végétation sahélienne en relation avec les indicateurs de dégradation au Burkina Faso

La variation spatiale du couvert vegetal constitue un des determinismes majeurs de la qualite des ecosystemes. Elle influence la physionomie  spatiale de la vegetation ainsi que les mutations des ressources naturelles. Lfobjectif de ce travail est dfexaminer la typologie spatiale de la vegetation sahelienne selon le taux de couverture vegetale en decrivant les glacis selon le stade de degradation a travers une caracterisationfonctionnelle et structurale. La variation spatiale de la couverture vegetale a ete determinee par utilisation dfune image satellitaire de type Modis appuyee dfobservations visuelles et dfinvestigations de terrain. Erdas Imagine 9.2 et ArcGIS.10 ont ete utilises pour la cartographie synchronique de lfindice Normalise Differentiel  de Vegetation (NDVI). Le taux de  couverture vegetale a ete visuellement apprecie sur le terrain. Des relevesphytosociologiques et dendrometriques ont ete faits et des variables  environnementales ont ete examinees et caracterisees. Au terme de cette etude, trois stades de degradation bases sur le taux de couverture  vegetale ont ete definis: le stade tres degrade (NDVI faible et couverture vegetale < 10%), le stade moyennement degrade (NDVI moyen et 10% . couverture vegetale < 30%) et le stade peu degrade (NDVI eleve et couverture vegetale . 30%). Les analyses multivariees montrent une importante dissimilarite entre les stades de degradation des glacis. La caracterisation comparative des variables a revele des differences  significatives. Lfanalyse statistique en composantes principales (ACP) basee sur une approche correlative a permis la mise en evidence des meilleures variables indicatrices de chaque stade de degradation. Cette etude constitue un outil dfaide a la caracterisation des stades de degradation des glacis saheliens, etape importante pour le suivi de ladesertification pour un amenagement durable des ecosystemes.Mots cles: Images satellitaires, couverture vegetale, stades de  degradation, variables indicatrices, amenagement durable, Burkina Faso

Teneurs en coumarines de 15 ligneux fourragers du Burkina Faso

Les antinutritionnels ont été le plus souvent ignorés dans l’évaluation de la qualité des fourrages ligneux dont la part augmente continuellement dans le bol alimentaire des ruminants au Burkina Faso. L’objectif de l’étude a été de caractériser et de quantifier les coumarines dans les feuilles et/ou les fruits de 15 ligneux fourragers couramment appétés par les ruminants à Diarabakoko et Dionona. Des tests de caractérisation en tubes ont été réalisés sur les échantillons frais collectés pour détecter la présence des coumarines. Des dosages spectrophotométriques des coumarines ont été également réalisés à partir des extraits frais des échantillons. L’étude a révélé la présence des coumarines chez toutes les espèces à des teneurs oscillant respectivement entre 10,590 ±0,354 et 31,174±0,477 μg EC/g d’extraits frais des feuilles et entre 1,250 ±0,014 et 22,899±0,561 μg EC/g d’extraits frais des fruits (P˂0,05). L’analyse des variances a permis de distinguer 2 classes de teneurs en coumarines des feuilles dont la première a les plus faibles valeurs. Nos résultats constituent des critères supplémentaires pour le choix des ligneux fourragers en aménagement pastoral et en agroforesterie. Ils montrent aussi que le fourrage (feuilles et fruits) des espèces étudiées peut contribuer sans danger à la supplémentation des ruminants. Mots clés : Alimentation, antinutritionnels, fourrage, aménagement pastoral, ruminant

Quantitative determination of chemical and biochemical parameters during « soumbala » manufacturing process in two communities of Burkina Faso

« Soumbala » is traditionally used in Burkina Faso as a food condiment in different communities. This study was conducted to evaluate « soumbala » manufacturing process on its nutritional value in two communities. During this descriptive and analytical study, samples were taken in the « Gouin » and « Moose » communities. The results show that, the humidity rate was higher in « soumbala » and waste in the « Gouin » processus, whereas in the « Moose » one, the highest humidity rate was observed after the cooking step and in peeled boiled seeds. The ash level was higher in raw seeds and after cooking step in the « Gouin » community whereas in the « Moose » community, it was higher in raw seeds and waste. The pH determination showed a progressive increase in pH values during the « soumbala » manufacturing process in the two communities. Mineral elements assays showed a slight variation in grades along the « soumbala » manufacturing process. For biochemical analysis, lipids content increased during the « soumbala » production; protein levels increased a little at the early stages of « soumbala » manufacturing process in both communities and carbohydrates contents were higher in waste in the « Moose » community, whereas in the « Gouin » community, the highest contents were found in the raw seeds. The aflatoxins determination in « soumbala » showed levels below the detection limit of the used method. These results showed that it was imperative that approved standard protocols be adopted to maintain the nutritional quality of « soumbala » wherever it is produced

Novel Genotyping Tools for Investigating Transmission Dynamics of Plasmodium falciparum

Background. Differentiation between gametocyte-producing Plasmodium falciparum clones depends on both high levels of stage-specific transcripts and high genetic diversity of the selected genotyping marker obtained by a high-resolution typing method. By analyzing consecutive samples of one host, the contribution of each infecting clone to transmission and the dynamics of gametocyte production in multiclone infections can be studied. Methods. We have evaluated capillary electrophoresis based differentiation of 6 length-polymorphic gametocyte genes. RNA and DNA of 25 µL whole blood from 46 individuals from Burkina Faso were simultaneously genotyped. Results. Highest discrimination power was achieved by pfs230 with 18 alleles, followed by pfg377 with 15 alleles. When assays were performed in parallel on RNA and DNA, 85.7% of all pfs230 samples and 59.5% of all pfg377 samples contained at least one matching genotype in DNA and RNA. Conclusions. The imperfect detection in both, DNA and RNA, was identified as major limitation for investigating transmission dynamics, owing primarily to the volume of blood processed and the incomplete representation of all clones in the sample tested. Abundant low-density gametocyte carriers impede clone detectability, which may be improved by analyzing larger volumes and detecting initially sequestered gametocyte clones in follow-up sample