Assessing soil nutrient change under long-term application of mineral fertilizer micro-dosing to pearl millet [Pennisetum glaucum (L.) R. Br.] on a sahelian sandy soil

In the Sahel, mineral fertilizer micro-dosing technique is known for its benefits to provide higher nutrient uptake and higher crop yields. A study was set up at ICRISAT research station at Sadoré in Niger, which aims at evaluating the sustainability of the technology in the long-term with emphasis on soil nutrients dynamics. The study has started since 2008 and was laid-out in a randomized complete block design that involved two pearl millet varieties, three planting densities, and four nutrients management options. For this study, a sub-set of the treatments from this long-term experiment was used. The nutrient management factor, which includes 4 levels was considered. The most important findings obtained indicated that the change in soil nutrient was markedly different on the planting hills and that from between hill. The change in soil pH-H2O values on the planting was -7.06 % for the control plots and -9.57 % for the plots applied with NPK. The total nitrogen content has dropped in the two different plots. The amplitude of drop has lowered with the application of NPK micro-dosing on the planting hills with respectively -5.11 % and -12.45 % in the control plots and the micro-dose plots. Positive change in available P was significantly observed (P≤0.05) in soil between hill with 1.08% in the control plots and 15.97 % in the amended plots. Both grain yield and total dry matter showed similar trend in which decreased yield was obvious over the time. In 2008, an average grain yield of 732 kg. ha-1 and 989 kg. ha-1 was obtained respectively for the control plots and 6g per hill of NPK plots. Whereas in 2016, 146 kg. ha-1 and 218 kg. ha-1 were produced respectively for the control plots and the mineral fertilizer micro-dosing plots. These findings indicated that in the Sahel low-input based millet cropping systems, for the mineral fertilizer micro-dosing technology to be sustainable in the long term, the improvement and maintenance of soil fertility should be considered as the cornerstone

Possibilities of sweet potato [Ipomoea batatas (L.) Lam] value chain upgrading as revealed by physico-chemical composition of ten elites landraces of Benin

Sweet potato is one of the most important food security promoted root crops in the world, especially in sub-Saharan Africa. Unfortunately, the crop is still neglected and underutilized in Benin Republic. To establish baseline data for its better utilization for upgrading its value chain, 10 selected local varieties (01 cream, 02 white, 03 yellow, and 04 orange flesh-colored) were compared for their macro-nutritional composition assessed using standard Association of Official Analytical Chemists (AOAC) procedures and spectrophotometry methods. The results indicate that sweet potato dry matter, protein, fiber, and ash content ranged from 46.11 to 25.9%, 4.09 to 1.97%, 1.81 to 3.00%, and 4.70 to 2.56%, respectively and orange flesh cultivars were found very rich. Pearson correlation analysis of variables revealed that dry mater content is positively correlated with carbohydrate and energy values, but negatively correlated with ash and fiber content, while starch content is strongly correlated with fiber content. Principal component analysis allowed us to classify the sweet potato varieties into 03 varietal groups among which Group 2 (05 varieties) exhibited rich fiber, ash, and protein contents and may be recommended for infant foods formulations. These results constitute important orientation for sweet potato processing chain organization in Benin and for the establishment of future nutrition and breeding programme.Key words: Benin, sweet potato, Ipomoea batatas, nutritional composition, orange flesh cultivar, value chain

From cassava to gari: Mapping of quality characteristics and end-user preferences in Cameroon and Nigeria

User's preferences of cassava and cassava products along the value chain are supported by specific root quality characteristics that can be linked to root traits. Therefore, providing an evidence base of user preferred characteristics along the value chain, can help in the functional choice of cassava varieties. In this respect, the present paper presents the results from focus group discussions and individual interviews on user preferred quality characteristics of raw cassava roots and the derived product, gari, ‐ one of the major cassava products in Sub Saharan Africa ‐ in major production and consumption areas of Cameroon and Nigeria. Choice of cassava varieties for farming is mainly determined by the multiple end‐uses of the roots, their agricultural yield and the processing determinants of roots that support their major high‐quality characteristics: size, density, low water content, maturity, colour and safety. Processing of cassava roots into gari goes through different technological variants leading to a gari whose high‐quality characteristics are: dryness, colour, shiny/attractive appearance, uniform granules and taste. Eba, the major consumption form of gari in Cameroon and Nigeria is mainly characterized by its textural properties: smoothness, firmness, stickiness, elasticity, mouldability. Recommendations are made, suggesting that breeding will have to start evaluating cassava clones for brightness/shininess, as well as textural properties such as mouldability and elasticity of cassava food products, for the purpose of supporting decision‐making by breeders and the development of high‐throughput selection methods of cassava varieties. Women are identified as important beneficiaries of such initiatives giving their disadvantaged position and their prominent role in cassava processing and marketing of gari

Rapid detection of multidrug resistant tuberculosis with a nitrate reductase assay using a liquid medium

IUATLD Conference, Paris, 200

Etude du systeme immunitaire des moustiques face aux insecticides: activites enzymatiques et mutations genetiques au sein des populations de Anopheles gambiae sensu lato (diptera: culicidae) dans la commune de Natitingou, au nord du Benin

Dans le but d’étudier le système immunitaire des moustiques face à l'utilisation des insecticides dans leur milieu écologique, une recherche a été initiée sur les activités enzymatiques et mutations génétiques de résistance au sein des populations  de Anopheles gambiae, principal vecteur du paludisme en Afrique subsaharienne dans la commune de Natitingou.Dans un premier temps, une enquête CAP (Connaissance, Attitude, Pratique) a été réalisée auprès des paysans afin de connaître les divers pesticides utilisés par ces derniers pour lutter contre les ravageurs des cultures. Puis, les femelles de Anopheles gambiae s.l âgées de 2-5 jours, issues des collectes larvaires des zones urbaines (Ourbourga, Kantaborifa), et rurales (Tigniti, Yimporima) dans la commune de Natitingou, ont été soumises aux tests de sensibilité réalisés avec des papiers imprégnés d’insecticides aux doses diagnostiques : perméthrine (0,75%), deltaméthrine (0,05%), DDT (4%) et du bendiocarb (0,1%). Enfin, nous avons recherché les mécanismes de résistance liés à la modification de cible Knock Down Resistance (KDR), de l’acétylcholinestérase (Ace1-R) sur les spécimens issus des tests de sensibilité et, les mécanismes enzymatiques (Glutathion-S-Transférase, estérase, monooxygénase P450 et protéine totale) à partir des populations F1 (issues de la population parentale après élevage).Les résultats des travaux indiquent : a)- une forte utilisation de pesticides chimiques par  les paysans entrainant une résistance de An. gambiae au DDT, perméthrine, deltaméthrine avec des taux de mortalités de 3% ; 23% et 30% respectivement contre une sensibilité vis-à-vis du bendiocarb quelle que soit la zone de collecte larvaire; b)- La mutation kdr semble être le principal mécanisme de résistance observé au sein de ces populations de An. gambiae avec une fréquence moyenne de 0,71 en zone rurale contre 0,68 en zone urbaine. La mutation Ace-1 a été également mise en évidence mais en de très faibles fréquences variant entre 0,02 à 0,05; c)-La présence d’activité enzymatique a été constatée dans toutes les populations de An. gambiae quelle que soit la localité.Ce travail a permis de montrer que les populations de An. gambiae de la commune de Natitingou ont un système immunitaire leur permettant d’être résistantes vis-à-vis des organochlorés, des pyréthrinoïdes et par une surproduction des enzymes. Ces résultats permettront ainsi aux décideurs de mieux gérer la résistance des vecteurs du paludisme aux insecticides pour mieux lutter contre le paludisme.Mots clés: Anopheles gambiae, Insecticides, Résistance, Natitingou, BéninEnglish Title: Immune system of mosquitoes against insecticides: enzymatic activities and genetic mutations in Anopheles gambiae sensu lato (diptera: culicidae) population in the district of Natitingou, northern-BeninEnglish AbstractIn order to study the immune system of the mosquito on the use of insecticide in their ecological environment, a study was carried out on enzyme activities and resistance genes in Anopheles gambiae population, the main malaria vector Sub-Saharan Africa in the district of Natitingou, northern BeninTo attend this goal, initially, Knowledge Attitude-Practice (KAP) surveys were organized at Natitingou, northern Benin in two urban areas (Ourbourga and Kantaborifa) and two rural areas (Tigniti and Yimporima). In each site, leaders of farmer’s organizations were interviewed using semi-structured questionnaires that focused on the treatment strategies, and the use of insecticides. This was complemented by bioassay tests to assess the susceptibility of An. gambiae where females aged to 2-5 were subjected to insecticide-impregnated papers (permethrin 0.75%, delthamethrin 0.05%, DDT 4%, and bendiocarb 0.1%) following WHO testing protocol. The species within An. gambiae complex, molecular form and presence of Knock Down mutation Resistance (KDR) and acetylcholinesterase (Ace-1R) mutation were determined by Polymerase Chain Reaction (PCR).Biochemical analysis was done in order to measure the Mixed Function Oxidase (MFO), non-specific esterase (NSE) and glutathione-S-transferases (GST) activity in individual 2-5 days old adult An. gambiae that had been reared from larvae and were not previously exposed to insecticides.This research showed: (i)-A wide spread of resistance to DDT, permethrin, delthamethrin with 3%, 23% and 30% of mortality rate respectively was found in samples of An. gambiae populations from Natitingou regardless the areas of collection. However, these populations were fully susceptible to bendiocarb; (ii)-The Kdr mutation was the main resistance mechanism detected in all the areas with frequency ranging between 0.68-0.71 The Ace-1 mutation was also found but at very low allelic frequency ranging between 0.02-0.05; (iii)-The activity of enzymes (oxidase, esterase and glutathion-S-transferases) was detected in all the mosquito populations.This work has highlighted multiple mechanisms of resistance in populations of Anopheles gambiae at Natitingou. This result will influence policy on recommendations about the use of bed nets and insecticides and will help to plan the future of malaria control.Keywords:  Anopheles gambiae, Insecticides, Resistance, Natitingou, Beni

Global burden of active smoking among people living with HIV on antiretroviral therapy: a systematic review and meta-analysis.

BACKGROUND: Although the high burden of both active smoking and human immunodeficiency virus (HIV) is clearly known, the relationship between them is still not well characterized. Therefore, we estimated the global prevalence of active smoking in people living with HIV (PLHIV) on antiretroviral therapy (ART) and investigated the association between exposure to active smoking and risk for suboptimal adherence to ART. Main text: We searched PubMed, Embase, and Web of Science to identify articles published until September 19, 2019. Eligible studies reported the prevalence of active smoking in PLHIV on ART or investigated the association between active smoking and ART adherence; or enough data to compute these estimates. We used a random-effects model to pool data and quantified heterogeneity (I2). The global prevalence of active smoking was 36.1% (95% CI: 33.7-37.2; 329 prevalence data; 462 104 participants) with substantial heterogeneity. The prevalence increased with level of country income; from 10.1% (95% CI: 6.8-14.1) in low-income to 45.2% (95% CI: 42.7-47.7) in high-income countries; P < 0.0001. With regards to the Joint United Nations Programme on HIV/AIDS (UNAIDS) regions, the prevalence was higher in West and Central Europe and North America 45.4% (42.7-48.1) and lowest in the two UNAIDS regions of sub-Saharan Africa: Eastern and Southern Africa 10.7% (95% CI: 7.8-14.0) and West and Central Africa 4.4% (2.9-6.3); P < 0.0001. Globally, we estimated that there were 4 110 669 PLHIV on ART who were active smokers, among which the highest number was from Eastern and Southern Africa (35.9%) followed by Asia and the Pacific (25.9%). Active smoking was significantly associated with suboptimal ART adherence: pooled odds ratio 1.57 (95% CI: 1.37-1.80; I2 = 56.8%; 19 studies; 48 450 participants); even after considering adjusted estimates: 1.67 (95% CI: 1.39-2.01; I2 = 53.0%; 14 studies). CONCLUSIONS: This study suggests a high prevalence of active smoking in PLHIV on ART and an association between active smoking and ART suboptimal adherence. As such, healthcare providers and policy makers should focus on adopting and implementing tobacco harm reduction strategies in HIV care, especially in sub-Saharan Africa known as epicenter of HIV pandemic with highest number of active tobacco smoking among PLHIV on ART

Infective endocarditis caused by on a prosthetic pulmonary valve with false positive serology for - The first described case.

We present a case of infective endocarditis (IE) on a prosthetic pulmonary valve in a 36-year-old patient with tetralogy of Fallot (TOF). The patient underwent valve replacement surgery and active antibiotic treatment against Gram-negative cocci (Piperacillin Tazobactam then Ceftriaxone) for a total duration of 42 days with a favourable outcome. The causative agent was which was identified on the infected valve by sequencing of 16S ribosomal RNA. To our knowledge, this is the first described case of a infective endocarditis on a pulmonary valve. Initially, serologies performed in clinical settings by immunofluorescence for antibodies showed a major increase in phase I IgG titers at 1024 (normal values &lt;16) corresponding with the diagnostic criteria for Q fever endocarditis. However, this diagnosis could not be confirmed by the National Reference Center, making it the first reported case of a false positive serology for during an infection due to&nbsp;spp.</p