Aptitude de trois souches de moisissures à produire des enzymes extracellulaires en milieu solide au Burkina Faso

Objectif: La présente étude a pour objectif la caractérisation physiologique de trois souches de moisissures S1, S2 et S3 isolées respectivement du maïs, de l’arachide et du riz au biais de leur capacité à produire des enzymes extracellulaires.Méthodologie et résultats: Au total, soixante-seize (76) échantillons d’aliments locaux ont été collectés dans des marchés centraux de trois villes du Burkina Faso. Deux cent soixante-douze (272) souches de moisissures ont été isolées et soumises au criblage indirect de production d’enzymes extracellulaires. Il consiste à estimer la production par mesure de la vitesse de croissance apicale des souches fongiques sur des milieux solides supplémentés par différents substrats carbonés. Le criblage a révélé l’activité protéolitique, amylolitiques, tannasiques, lipolitique et cellulosique de trois souches de moisissures. Selon les clés d’identification de Raper & Fennell (1965) et Pitt (1985), ces trois souches S1, S2 et S3 sont respectivement Aspergillus fumigatus, Aspergillus flavus et Penicillium citrinum.Conclusion et application: Les micro-organismes en général et les champignons en particulier constituent des sources d'enzymes plus facilement exploitables que celles des végétaux ou les animaux à cause de la simplicité de purification. Les enzymes fongiques restent toujours les outils clés de la biotechnologie et reflètent de plus en plus l’importance et le rôle infini des moisissures dans les différentes applications alimentaires. Parmi ces enzymes, les lipases, les phytases et les tannases sont perçues comme étant des enzymes importantes en industrie. Cependant, le principal obstacle qui freine les applications potentielles de ces enzymes est leur coût. Des souches locales productrices d’intéressantes enzymes pourraient contribuer à l’amoindrir.Mots clés: enzymes extracellulaires, aliments locaux, moisissures, milieu solide, croissance apicaleEnglish Title: The ability of three strains of fungi to produce extracellular enzymes on solid state in Burkina FasoEnglish AbstractObjective: The aim of this study is the physiological characterization of three fungi strains S1, S2 and S3 respectively isolated from maize, groundnuts and rice through their ability to produce extracellular enzymes.Methods and Results: A total of seventy-six (76) samples of local foods were collected in centrals markets of three cities in Burkina Faso. Two hundred and seventy-two (272) fungi strains were isolated and submitted to extracellular enzymes indirect screening production. It was consisted by measuring the apical growth rate of the fungi strains on solid media supplemented with various carbon substrates. The screening revealed the proteolytic, amylolitic, tannasic, lipolytic and cellulosic activities of three fungi strains. According to the Raper & Fennell (1965) and Pitt (1985) identification key, these three strains S1, S2 and S3 are respectively Aspergillus fumigatus, Aspergillus flavus and Penicillium citrinum.Conclusion and Application: Micro-organisms in general and filamentous fungi in particular are rich sources of enzymes more easily exploitable than those of plants or animals due to the simplicity in purification. Fungal enzymes remain biotechnology key tools and reflect increasingly important and the infinity role of mold in various food applications. Among these enzymes, lipases, phytases and tannases are perceived as important enzymes in industry. However, the main obstacle hindering the potential applications of these enzymes is their cost. Local fungi strains with interesting enzymes property could help cost decreasing.Keywords: extracellular enzymes, local foods, fungi, solid state, apical growt

Towards innovative solutions for monitoring precipitation in poorly instrumented regions: real-time system for collecting power levels of microwave links of mobile phone operators for rainfall quantification in Burkina Faso

Since the 1990s, mobile telecommunication networks have gradually become denser around the world. Nowadays, large parts of their backhaul network consist of commercial microwave links (CMLs). Since CML signals are attenuated by rainfall, the exploitation of records of this attenuation is an innovative and an inexpensive solution for precipitation monitoring purposes. Performance data from mobile operators’ networks are crucial for the implementation of this technology. Therefore, a real-time system for collecting and storing CML power levels from the mobile phone operator “Telecel Faso” in Burkina Faso has been implemented. This new acquisition system, which uses the Simple Network Management Protocol (SNMP), can simultaneously record the transmitted and received power levels from all the CMLs to which it has access, with a time resolution of one minute. Installed at “Laboratoire des Matériaux et Environnement de l’Université Joseph KI-ZERBO (Burkina Faso)”, this acquisition system is dynamic and has gradually grown from eight, in 2019, to more than 1000 radio links of Telecel Faso’s network in 2021. The system covers the capital Ouagadougou and the main cities of Burkina Faso (Bobo Dioulasso, Ouahigouya, Koudougou, and Kaya) as well as the axes connecting Ouagadougou to these citie

Genetic Diversity of Jatropha curcas in Burkina Faso Revealed by Microsatellite Markers

Jatropha curcas L. is a perennial oleaginous plant commonly used in tropical areas as a medicinal plant in the construction of defensive hedges against animals, and in the fight against water erosion. It produces oil which can be used as agrofuel or soap-making. Despite its potential, the species remain under-exploited and its genetic diversity is still not very well-known in Burkina Faso. This paper focuses on determining the level and structure of the genetic diversity of 50 accessions collected in three phytogeographical sectors of the country using 12 microsatellite markers. Resultsrevealed a total of 37 alleles in the studied population with an average of 3 alleles per locus, a number of 2.717 effective alleles, and a Shannon diversity index of 1.663. Mean observed heterozygosity and mean expected heterozygosity were 0.144 and 0.356, respectively. Accessions were structured into three genetic groups. The high genetic distance of 0.177 was observed between groups A and B, and a low genetic distance of 0.075 was observed between groups B and C. These preliminary results showed that microsatellites are promising tools that can be used for the characterization of J. curcas. They indicate that the population studied has a low genetic diversity, but it is sufficient to develop programs for conservation and sustainable development of the species

Confirmation de QTL et validation de marqueurs SNPs associés à la résistance du niébé à Colletotrichum capsici, agent responsable de la maladie des taches brunes

Le niébé (Vigna unguiculata (L.) Walp.) est une légumineuse à graine très importante et constitue la principale source de protéines végétales pour l’alimentation des populations d’Afrique Subsaharienne. Sa production au Burkina Faso est entravée par la maladie des taches brunes provoquée par un champignon, Colletotrichum capsici (Syd.) Butler et Bisby. C’est dans la perspective d’accroître la productivité du niébé que nous avons entrepris de renforcer la lutte variétale contre cet agent pathogène. L’identification de marqueurs SNPs (Single Nucleotide Polymorphism) et QTL liés à la résistance à la maladie des taches brunes a été entrepris à partir d’une population biparentale F2 issus du croisement entre la variété sensible Tiligré et celle résistante KN-1. L’analyse QTL de la résistance du niébé à C. capsici à partir de la méthode ICIM add. a permis de confirmer et de valider respectivement un QTL majeur dénommé qBBDR2.1 et 9 marqueurs SNPs convertis, lesquels ont été cartographiés sur le chromosome Vu02 du niébé. Ce QTL dominant a présenté des effets additifs élevés liés aux allèles favorables de KN-1 et des valeurs de PVE de l’ordre de 51,50% et 55,33%, respectivement aux 21ème et 28ème JAI. English title: Confirmation of QTL mapping and validation of SNPs markers associated to cowpea resistance to Colletotrichum capsici, causal agent of brown blotch disease Cowpea (Vigna unguiculata (L.)Walp.) is one of the most important grain legume crops and constitutes the main source of plant protein for people food in sub-Saharan Africa. Cowpea production in Burkina Faso is constrained by brown blotch disease caused by a fungal,  Colletotrichum capsici (Syd.) Butler and Bisby. In order to increase cowpea productivity we initiated a project to enhance host plant resistance to control the pathogen. The identification of SNP (Single Nucleotide Polymorphism) markers and QTL associated with brown blotch disease resistance was undertaken from a bi-parental F2 population resulting from a cross between the sensitive variety Tiligre and the resistant KN-1 to the disease. QTL analysis of cowpea resistance to C. capsici using the ICIM add method. Allowed to confirm and validate respectively a major QTL named qBBDR2.1 and 9 converted SNP markers, which were mapped on cowpea chromosome Vu02. This dominant QTL showed higher additive effects associated to alleles from KN-1 and PVE values of 51.50% and 55.33% respectively at 21 and 28 days after inoculatio

Mortalité néonatale au centre hospitalier universitaire de Tengandogo, Ouagadougou, Burkina Faso: une étude de cohorte retrospective: Neonatal mortality at Tengandogo University Hospital, Ouagadougou, Burkina Faso: a retrospective cohort study

Introduction: Selon l’organisation mondiale de la santé, les décès néonataux représentent 41% de la mortalité infanto-juvénile. L’Afrique subsaharienne a le taux de mortalité néonatale le plus élevé à 28‰. L’objectif de l’étude était de mesurer le taux de mortalité néonatale et d’identifier les facteurs associés au décès au Centre hospitalier universitaire de Tengandogo, Ouagadougou, Burkina Faso. Méthodes: Les nouveaux nés de 0 à 28 jours, hospitalisés entre le 1er janvier 2013 et le 31 décembre 2017 ont été inclus dans cette étude de cohorte rétrospective au service de néonatologie et de pédiatrie. Les informations ont été extraites à partir des dossiers cliniques. La survie a été estimée par la méthode de Kaplan Meier. Un modèle de Cox a permis d’identifier les facteurs associés. Résultats: Au total 641 nouveau-nés ont été inclus. Les enfants admis dès le premier jour de leur naissance représentaient 80%. La durée médiane de séjour était de 6 jours avec un intervalle interquartile de 3-12 jours. Les principaux diagnostics étaient la prématurité (36,05%), les infections néonatales (33,23%) et l’asphyxie (17,86%). Le taux de mortalité néonatale était de 22,25 pour 1000 personnes jours. Après ajustement, le poids de naissance inferieur 1500gramme (HRa = 4,13 ; IC 95% (2,58-6,67)) et la notion de réanimation à la naissance (HRa2,62 ; IC 95% [1,64-4,39)) étaient les facteurs de risque. Conclusion: Le taux de mortalité néonatale reste élevé. Le suivi prénatal, la prévention des infections, le renforcement des moyens de réanimation et la compétence des acteurs sont essentiels pour réduire ce taux. Introduction: According to the World Health Organization, neonatal deaths account for 41% of infant and child mortality. Sub-Saharan Africa has the highest neonatal mortality rate at 28‰. The objective of the study was to measure the neonatal mortality rate and identify factors associated with death at the Tengandogo University Hospital, Ouagadougou, Burkina Faso. Method: New-borns aged 0 to 28 days, hospitalised between 1 January 2013 and 31 December 2017 were included in this retrospective cohort study in the neonatology and paediatrics department. Information was extracted from clinical records. Survival was estimated by the Kaplan Meier method. A Cox model was used to identify associated factors. Results: A total of 641 new-borns were included. Children admitted on the first day of birth accounted for 80%. The median length of stay was 6 days with an interquartile range of 3-12 days. The main diagnoses were prematurity (36.05%), neonatal infections (33.23%) and asphyxia (17.86%). The neonatal mortality rate was 22.25 per 1000 person days. After adjustment, birth weight below 1500 grams (HRa = 4.13; 95% CI (2.58-6.67)) and the notion of resuscitation at birth (HRa2.62; 95% CI (1.64-4.39)) were the risk factors. Conclusion: The neonatal mortality rate remains high. Prenatal follow-up, infection prevention, strengthening of resuscitation resources and competence of actors are essential to reduce this rate

Screening of BRCA1 (c.5177_5180delGAAA rs80357867 and c.4986+6T>C rs80358086) and the BRCA2 (c.6445_6446delAT rs80359592) genes for breast cancer prevention in Burkina Faso

BACKGROUND: The objective of this study is to search for mutations in the BRCA1 (c.5177_5180delGAAA and c.4986+6T>C) and BRCA2 genes (c.6445_6446delAT) in a population of women diagnosed with breast cancer.METHODS: This is a case-control study that involved 140 participants, including 70 patients with histologically diagnosed breast cancer and 70 healthy women without breast cancer. Mutations in the BRCA1 (rs80357867, rs80358086) and BRCA2 (rs80359592) genes were tested by real-time PCR. The 95% confidence interval Odds Ratio (OR) was used to estimate the associations between specific genotypes and breast cancer.RESULTS: The study revealed that no mutations were detected for rs80359592. Similarly, no reference allele (TTTC/TTTC) of rs80357867 was found in this study. However, the homozygous double mutant (-/) genotype of this rs80357867 was observed in 11.43% and 1.43% of patients and controls respectively, while 88.57% of patients and 98.57% of controls had a heterozygous deletion (TTTC/-). Concerning rs80358086, 8.57% of the patients had a heterozygous mutation (A/G) with no significantly risk association with occurrence of breast cancer (OR = 6.46; 95% CI: 0.75-55.21; p = 0.11). In addition, this heterozygous mutation was significantly associated with a family history of breast cancer (OR=128; 95% CI: 9.46-1730.93) and breast cancer risk in nonmultiparous women (OR=6; 95% CI: 1-35.90; p= 0.05) but no association with overweight/obesity (OR=1.66; 95% CI: 0.18-15.35; p=1).CONCLUSION: This study shows high frequencies of heterozygous mutation of rs80357867 and rs80358086 from patients. In Burkina Faso, these results could help with early diagnosis of breast cancer in patients

Immunologic response in treatment-naïve HIV-2-infected patients:the IeDEA West Africa cohort

Introduction: Response to antiretroviral therapy (ART) among individuals infected with HIV-2 is poorly described. We compared the immunological response among patients treated with three nucleoside reverse-transcriptase inhibitors (NRTIs) to boosted protease inhibitor (PI) and unboosted PI-based regimens in West Africa. Methods: This prospective cohort study enrolled treatment-naïve HIV-2-infected patients within the International Epidemiological Databases to Evaluate AIDS collaboration in West Africa. We used mixed models to compare the CD4 count response to treatment over 12 months between regimens. Results: Of 422 HIV-2-infected patients, 285 (67.5%) were treated with a boosted PI-based regimen, 104 (24.6%) with an unboosted PI-based regimen and 33 (7.8%) with three NRTIs. Treatment groups were comparable with regard to gender (54.5% female) and median age at ART initiation (45.3 years; interquartile range 38.3 to 51.8). Treatment groups differed by clinical stage (21.2%, 16.8% and 17.3% at CDC Stage C or World Health Organization Stage IV for the triple NRTI, boosted PI and unboosted PI groups, respectively, p=0.02), median length of follow-up (12.9, 17.7 and 44.0 months for the triple NRTI, the boosted PI and the unboosted PI groups, respectively, p<0.001) and baseline median CD4 count (192, 173 and 129 cells/µl in the triple NRTI, the boosted PI and the unboosted PI-based regimen groups, respectively, p=0.003). CD4 count recovery at 12 months was higher for patients treated with boosted PI-based regimens than those treated with three NRTIs or with unboosted PI-based regimens (191 cells/µl, 95% CI 142 to 241; 110 cells/µl, 95% CI 29 to 192; 133 cells/µl, 95% CI 80 to 186, respectively, p=0.004). Conclusions: In this observational study using African data, boosted PI-containing regimens had better immunological response compared to triple NRTI combinations and unboosted PI-based regimens at 12 months. A randomized clinical trial is still required to determine the best initial regimen for treating HIV-2 infected patients

Additional Screening and Treatment of Malaria During Pregnancy Provides Further Protection Against Malaria and Nonmalarial Fevers During the First Year of Life.

Background: Although consensus exists that malaria in pregnancy (MiP) increases the risk of malaria in infancy, and eventually nonmalarial fevers (NMFs), there is a lack of conclusive evidence of benefits of MiP preventive strategies in infants. Methods: In Burkina Faso, a birth cohort study was nested to a clinical trial assessing the effectiveness of a community-based scheduled screening and treatment of malaria in combination with intermittent preventive treatment with sulfadoxine-pyrimethamine (CSST/IPTp-SP) to prevent placental malaria. Clinical episodes and asymptomatic infections were monitored over 1 year of follow-up to compare the effect of CSST/IPTp-SP and standard IPTp-SP on malaria and NMFs. Results: Infants born during low-transmission season from mothers receiving CSST/IPTp-SP had a 26% decreased risk of experiencing a first clinical episode (hazard ratio, 0.74 [95% confidence interval, .55-0.99]; P = .047). CSST/IPTp-SP interacted with birth season and gravidity to reduce the incidence of NMFs. No significant effects of CSST/IPTp-SP on the incidence of clinical episodes, parasite density, and Plasmodium falciparum infections were observed. Conclusions: Our findings indicate that CSST/IPTp-SP strategy may provide additional protection against both malaria and NMFs in infants during the first year of life, and suggest that malaria control interventions during pregnancy could have long-term benefits in infants