Multiplication and preliminary characterization of west and central African pearl millet landraces

West Africa is a center of origin and diversity of pearl millet [Pennisetum glaucum (L.) R. Br.], but this diversity is neither well-understood nor fully accessible to and exploited by NARS breeders and farmers. The objective of the present study was to multiply and initially characterize 281 pearl millet accessions from all over West and Central Africa, with the final aim of promoting a more systematic and targeted exploitation of genetic diversity in adapted germplasm in West African pearl millet improvement programs

Mechanisms of adaptation to climate variability in West African pearl millet landraces – a preliminary

Landraces are generally expected to possess specific mechanisms of adaptation to their growing environments. In West and Central Africa (WCA), growing conditions of pearl millet (Pennisetum glaucum) are characterized, among other hazards, by highly variable beginnings and endings of the rainy season, and unpredictable drought stress at any time during the growing season. Adaptation to such unpredictable variable environment can be due to individual and/or populational buffering (Allard and Bradshaw 1964), two mechanisms initially defined by Lerner (1954) as developmental and genetic homeostasis. Individual buffering may be favored by phenotypic plasticity. Photoperiod-sensitive flowering is an example of phenotypic plasticity that can enhance adaptation to variable planting dates followed due to a scattered beginning of the rainy season in a region, as typical for WCA. It enhances simultaneous flowering of the cultivar in the target region, independent of the individual date of planting in different fields. This has particular advantages in terms of reducing bird damage and insect pressure; prolonging vegetative development in case of early planting but accelerating development in case of late planting; therefore fitting plant development to available rainfall patterns and resulting potentially in increased yielding stability. Populational buffering can be promoted by genetic heterogeneity in plant stand as different genotypes present in the population are specifically adapted to different environmental conditions (Bradshaw 1965). An example is intra-varietal variation for flowering time, which would assure that in case of a dry spell, not all plants in the field will be affected by drought in their most sensitive flowering stage

Uncertain pasts and risk-sensitive futures in sub-Saharan urban transformation

This chapter explores the status and the scope for transition of risk- sensitive and transformative urban development in diverse cities of sub-Saharan Africa. Sub-Saharan Africa is important because of its large proportions of urban populations with high vulnerability and growing exposure to risks. High rates of urban growth pose increasing risks as we go into the future, yet there is also opportunity to reduce risk through integrating risk management into development. However, this opportunity space is often constrained by limited capacities to plan and manage the rapid urbanisation process, particularly in informal settlements. Limited capacities to prevent processes of risk accumulation pose threats to poverty reduction and sustainable development. In this context, there is an increasingly urgent need for squarely recognising and addressing the underlying vulnerabilities of urban populations and their root causes. Transitioning towards such sustainable urban pathways will require the strengthening of capacities and accountability of city authorities and broader governance systems, both formal and informal

PD-1 Co-inhibitory and OX40 Co-stimulatory Crosstalk Regulates Helper T Cell Differentiation and Anti-Plasmodium Humoral Immunity

SummaryThe differentiation and protective capacity of Plasmodium-specific T cells are regulated by both positive and negative signals during malaria, but the molecular and cellular details remain poorly defined. Here we show that malaria patients and Plasmodium-infected rodents exhibit atypical expression of the co-stimulatory receptor OX40 on CD4 T cells and that therapeutic enhancement of OX40 signaling enhances helper CD4 T cell activity, humoral immunity, and parasite clearance in rodents. However, these beneficial effects of OX40 signaling are abrogated following coordinate blockade of PD-1 co-inhibitory pathways, which are also upregulated during malaria and associated with elevated parasitemia. Co-administration of biologics blocking PD-1 and promoting OX40 signaling induces excessive interferon-gamma that directly limits helper T cell-mediated support of humoral immunity and decreases parasite control. Our results show that targeting OX40 can enhance Plasmodium control and that crosstalk between co-inhibitory and co-stimulatory pathways in pathogen-specific CD4 T cells can impact pathogen clearance

A qualitative study of women’s and health providers’ attitudes and acceptability of mistreatment during childbirth in health facilities in Guinea

BACKGROUND: Reducing maternal morbidity and mortality remains a key health challenge in Guinea. Anecdotal evidence suggests that women in Guinea are subjected to mistreatment during childbirth in health facilities, but limited research exists on this topic. This study was conducted to better understand the social norms and the acceptability of four scenarios of mistreatment during childbirth, from the perspectives of women and service providers. METHODS: This study used qualitative methods including in-depth interviews (IDIs) and focus group discussions (FGDs) with women of reproductive age, midwives, nurses and doctors. This study was conducted in one urban area (Mamou) and one peri-urban area (Pita) in Guinea. Participants were presented with four scenarios of mistreatment during childbirth, including a provider: (1) slapping a woman; (2) verbally abusing a woman; (3) refusing to help a woman; and (4) forcing a woman to give birth on the floor. Data were collected in local languages (Pular and Malinké) and French, and transcribed and analyzed in French. We used a thematic analysis approach and manually coded the data using a codebook developed for the project. RESULTS: A total of 40 IDIs and eight FGDs were conducted with women of reproductive age, 5 IDIs with doctors, and 13 IDIs with midwives. Most women were not accepting of any of the scenarios, unless the action was perceived to be used to save the life of the mother or child. However, they perceived a woman’s disobedience and uncooperativeness to contribute to her poor treatment. Women reacted to this mistreatment by accepting poor treatment, refusal to use the same hospital, revenge against the provider or complaints to hospital management. Service providers were accepting of mistreatment when women were disobedient, uncooperative, or to save the life of the baby. CONCLUSIONS: This is the first known study on mistreatment of women during childbirth to be conducted in Guinea. Both women and service providers were accepting of mistreatment during childbirth under certain conditions. Any approach to preventing and eliminating mistreatment during childbirth must consider these important contextual and social norms and develop a comprehensive intervention that addresses root causes. Further research is needed on how to measure mistreatment during childbirth in Guinea

Cross-Clade Recognition of HIV-1 CAp24 by CD4+ T Cells in HIV-1-Infected Individuals in Burkina Faso and Germany

The presence of antigen-specific cellular immune responses may be an indicator of long-term asymptomatic HIV-1-disease. The detection of cellular immune responses to infection with different subtypes of HIV-1 may be hampered by genetic differences of immunodominant antigens such as the capsid protein CAp24. In Nouna, Burkina Faso, HIV-1 circulating recombinant forms CRF02_AG and CRF06_cpx are the 2 major strains detectable in HIV-1-infected individuals, while subtype B strains prevail in Europe and North America. Amino acid sequences of CAp24 were assessed in blood samples from 10 HIV-1-infected patients in Nouna, Burkina Faso. Production of interferon-gamma (IFN-γ) in peripheral blood CD4+ lymphocytes in response to recombinant HIV-1 proteins derived from clade B (including CAp24NL4-3) was measured using a modified flow-cytometry-based whole blood short term activation assay (FASTimmune, BDBiosciences). IFN-γ production following stimulation with a whole length CAp24 protein derived from clade B (CAp24NL4-3) was additionally quantified in comparison to a CAp24 protein derived from CRF02_AG (CAp24BD6-15) in 16 HIV-1-infected patients in Heidelberg, Germany. Amino acid sequence identity of CAp24 obtained from patients in Nouna ranged between 86 and 89% when compared to the clade B CAp24NL4-3 consensus sequence, between 90 and 95% when compared to the circulating recombinant form CRF06_CPX consensus sequence, and between 92 and 96% when compared to the CAp24BD6-15 consensus sequence. Significant numbers of HIV-1-specific CD4+ lymphocytes producing IFN-γ were detected in 4 of 10 HIV-1-infected patients. In 7 of 16 patients in Heidelberg, recombinant CAp24BD6-15 stimulated IFN-γ-production in CD4+ lymphocytes to a similar extent as the clade B-derived CAp24NL4-3. Thus, antigen-specific CD4+ lymphocytes from both West African and European patients infected with different strains of HIV-1 show relevant cross-clade recognition of HIV-1 CAp24 in a flow-cytometry-based whole blood short term activation assay

Urinary schistosomiasis among preschool-aged children in Sahelian rural communities in Mali

<p>Abstract</p> <p>Background</p> <p>Mass chemotherapy with praziquantel is the main control strategy for schistosomiasis in Mali. However, in the national control programme for schistosomiasis and soil-transmitted helminthiasis, infants and preschool-aged children are overlooked in preventive chemotherapy campaigns. We therefore determined the prevalence and intensity of urinary schistosomiasis in children between the ages 1-4 years in three villages across Diema health district, a rural community with endemic schistosomiasis in Mali. For <it>Schistosoma haematobium </it>diagnosis, a single urine sample of 10 ml obtained from each child was subjected to the standard urine filtration method.</p> <p>Results</p> <p>Of the 338 children examined 173 (51.2%) were infected. Both prevalence and intensity of infection varied significantly between communities (p < 0.01). There was no significant difference (p = 0.94) in infection rates between boys (51.2%) and girls (50.3%). Likewise, prevalence did not significantly increase with age (p = 0.86). The overall geometric mean of Williams (GMw) was 18.41 eggs/10 ml urine, with no significant association (p = 0.91) between boys (17.48 eggs/10 ml urine) and girls (19.69 eggs/10 ml urine). However, the GMw significantly increased with age (p = 0.04). Infection of preschool children would occur through early exposure to infected water bodies through both passive and active process.</p> <p>Conclusion</p> <p>Our study showed that preschool children living closely to lakes across in Mali are at high risk to be infected by schistosomiasis and contributed largely to the transmission; therefore schistosomiasis control interventions should also target infants in addition to school children and adults in endemic areas.</p

System-level determinants of immunization coverage disparities among health districts in Burkina Faso: a multiple case study

<p>Abstract</p> <p>Background</p> <p>Despite rapid and tangible progress in vaccine coverage and in premature mortality rates registered in sub-Saharan Africa, inequities to access remain firmly entrenched, large pockets of low vaccination coverage persist, and coverage often varies considerably across regions, districts, and health facilities' areas of responsibility. This paper focuses on system-related factors that can explain disparities in immunization coverage among districts in Burkina Faso.</p> <p>Methods</p> <p>A multiple-case study was conducted of six districts representative of different immunization trends and overall performance. A participative process that involved local experts and key actors led to a focus on key factors that could possibly determine the efficiency and efficacy of district vaccination services: occurrence of disease outbreaks and immunization days, overall district management performance, resources available for vaccination services, and institutional elements. The methodology, geared toward reconstructing the evolution of vaccine services performance from 2000 to 2006, is based on data from documents and from individual and group interviews in each of the six health districts. The process of interpreting results brought together the field personnel and the research team.</p> <p>Results</p> <p>The districts that perform best are those that assemble a set of favourable conditions. However, the leadership of the district medical officer (DMO) appears to be the main conduit and the rallying point for these conditions. Typically, strong leadership that is recognized by the field teams ensures smooth operation of the vaccination services, promotes the emergence of new initiatives and offers some protection against risks related to outbreaks of epidemics or supplementary activities that can hinder routine functioning. The same is true for the ability of nurse managers and their teams to cope with new situations (epidemics, shortages of certain stocks).</p> <p>Conclusion</p> <p>The discourse on factors that determine the performance or breakdown of local health care systems in lower and middle income countries remains largely concentrated on technocratic and financial considerations, targeting institutional reforms, availability of resources, or accessibility of health services. The leadership role of those responsible for the district, and more broadly, of those we label "the human factor", in the performance of local health care systems is mentioned only marginally. This study shows that strong and committed leadership promotes an effective mobilization of teams and creates the conditions for good performance in districts, even when they have only limited access to supports provided by external partners.</p> <p>Abstract in French</p> <p>See the full article online for a translation of this abstract in French.</p

Exceptional Diversity, Maintenance of Polymorphism, and Recent Directional Selection on the APL1 Malaria Resistance Genes of Anopheles gambiae

The three-gene APL1 locus encodes essential components of the mosquito immune defense against malaria parasites. APL1 was originally identified because it lies within a mapped QTL conferring the vector mosquito Anopheles gambiae natural resistance to the human malaria parasite, Plasmodium falciparum, and APL1 genes have subsequently been shown to be involved in defense against several species of Plasmodium. Here, we examine molecular population genetic variation at the APL1 gene cluster in spatially and temporally diverse West African collections of A. gambiae. The locus is extremely polymorphic, showing evidence of adaptive evolutionary maintenance of genetic variation. We hypothesize that this variability aids in defense against genetically diverse pathogens, including Plasmodium. Variation at APL1 is highly structured across geographic and temporal subpopulations. In particular, diversity is exceptionally high during the rainy season, when malaria transmission rates are at their peak. Much less allelic diversity is observed during the dry season when mosquito population sizes and malaria transmission rates are low. APL1 diversity is weakly stratified by the polymorphic 2La chromosomal inversion but is very strongly subdivided between the M and S “molecular forms.” We find evidence that a recent selective sweep has occurred at the APL1 locus in M form mosquitoes only. The independently reported observation of a similar M-form restricted sweep at the Tep1 locus, whose product physically interacts with APL1C, suggests that epistatic selection may act on these two loci causing them to sweep coordinately