Analyse physico-chimique de l’eau de l’unité d’hémodialyse du chr de Saint- Louis (Sénégal)

L’insuffisance rénale chronique est un des problèmes majeurs de la santé publique dans le monde. Au Sénégal, une étude récente réalisée dans la population générale adulte avait retrouvé une prévalence de l’ordre de 6,1%. «L’eau pour dilution de concentrées d’hémodialyse» est produite en continue et utilisée en grande quantité chez l’hémodialysé chronique, donc il apparaît primordial de veiller à sa bonne qualité. Au Sénégal, aucune étude n’a été faite à ce jour pour évaluer l’efficacité du système de traitement de l’eau pour dilution des concentrés de dialyse dans les différents centres de dialyse du pays. L’objectif de ce travail est de contrôler l’efficacité du système de traitement de l’eau pour dilution de concentrées d’hémodialyse afin de s’assurer de son innocuité. Les prélèvements ont été effectués au niveau de trois points clés du circuit de traitement de l’eau pour hémodialyse. A l’entrée et à la sortie de l’osmoseur, à la sortie de la boucle de distribution. Les analyses ont été effectuées à l’aide d’électrodes spécifiques. Les valeurs de potentiels ont permis de tracer les courbes d’étalonnage. La détermination par régression des pentes et des ordonnées à l’origine de la relation de Nernst donne E(mV ) = B - A Log Cm avec des coefficients de corrélation variant entre 0,988 et 0,999 prouvant que 98% au moins des variations de tensions mesurées (E) sont attribuables à la concentration. L’analyse physico-chimique des teneurs en chlorures, nitrates et fluorures révèle des teneurs plus élevées à l’entrée de l’osmoseur qu’à la sortie. Ces basses valeurs découlent du rôle de l’osmoseur qui filtre une grande partie des électrolytes. Par contre, à la sortie de la boucle de distribution les teneurs en électrolytes des différents échantillons étaient plus importantes que celles à la sortie de l’osmoseur. Cette forte concentration en électrolytes atteste d’une pollution par la boucle de distribution de l’eau déjà filtrée par l’osmoseur. L’intérêt de cette étude réside dans le fait qu’elle met en lumière l’importance du contrôle de la qualité de l’eau pour l’hémodialyse et la nécessité d’un bon planning de maintenance préventive efficace de l’ensemble de la boucle de traitement d’eau au sein de chaque centre.© 2016 International Formulae Group. All rights reserved.Mots clés: Hémodialyse, eau, chlorures, fluorures, nitrates, électrodes spécifiquesEnglish Title: Physicochemical analysis of Saint–Louis regional hospital’s hemodialysis unit’s water (Senegal)English AbstractChronic kidney disease is a major public health problem worldwide. In Senegal, a recent study in the general adult population found a prevalence of about 6,1%. "Water for diluting concentrated hemodialysis" is produced and used continuously at high levels in hemodialysis chronic. It is therefore essential to ensure its quality. In Senegal, no study has been done to assess the effectiveness of water treatment system for dialysis concentrates dilution in different dialysis centers of the country. The objective of this work is to monitor the effectiveness of the water treatment system for hemodialysis concentrated dilution to ensure its safety. The samples were taken on key issues of hemodialysis water’s treatment circuit. Three levels of sampling were selected. At the entrance and at the outlet of the reverse osmosis unit at the outlet of the distribution loop. Analyses were performed using specific electrodes. Potential values allowed us to map the calibration curves. Determination by regression of slopes and intercepts of the Nernst relation gives with correlation coefficients ranging from 0.988 to 0.999 showing that at least 98% of the measured voltages fluctuations (E) are attributable to the concentration. Physicochemical analysis of the levels of chlorides, nitrates and fluorides reveals higher levels at the entrance of the reverse osmosis unit than at the outlet. These low values resulting of the role of reverse osmosis which filter much of the electrolytes. For against, at the outlet of the distribution loop the electrolyte content of the different samples were greater than those at the outlet of the reverse osmosis unit. This high electrolyte concentration attests to pollution of the water distribution loop already filtered by reverse osmosis. The interest of this study lies in the fact that it highlights the importance of monitoring the quality of water for hemodialysis and the need for good planning for effective preventive maintenance throughout the water treatment loop within each center.© 2016 International Formulae Group. All rights reserved.Keywords: Hemodialysis, water, nitrates, fluoride, chloride, specific electrode

Gene expression profiling in blood from cerebral malaria patients and mild malaria patients living in Senegal

International audienceBACKGROUND:Plasmodium falciparum malaria remains a major health problem in Africa. The mechanisms of pathogenesis are not fully understood. Transcriptomic studies may provide new insights into molecular pathways involved in the severe form of the disease.METHODS:Blood transcriptional levels were assessed in patients with cerebral malaria, non-cerebral malaria, or mild malaria by using microarray technology to look for gene expression profiles associated with clinical status. Multi-way ANOVA was used to extract differentially expressed genes. Network and pathways analyses were used to detect enrichment for biological pathways.RESULTS:We identified a set of 443 genes that were differentially expressed in the three patient groups after applying a false discovery rate of 10%. Since the cerebral patients displayed a particular transcriptional pattern, we focused our analysis on the differences between cerebral malaria patients and mild malaria patients. We further found 842 differentially expressed genes after applying a false discovery rate of 10%. Unsupervised hierarchical clustering of cerebral malaria-informative genes led to clustering of the cerebral malaria patients. The support vector machine method allowed us to correctly classify five out of six cerebral malaria patients and six of six mild malaria patients. Furthermore, the products of the differentially expressed genes were mapped onto a human protein-protein network. This led to the identification of the proteins with the highest number of interactions, including GSK3B, RELA, and APP. The enrichment analysis of the gene functional annotation indicates that genes involved in immune signalling pathways play a role in the occurrence of cerebral malaria. These include BCR-, TCR-, TLR-, cytokine-, FcεRI-, and FCGR- signalling pathways and natural killer cell cytotoxicity pathways, which are involved in the activation of immune cells. In addition, our results revealed an enrichment of genes involved in Alzheimer's disease.CONCLUSIONS:In the present study, we examine a set of genes whose expression differed in cerebral malaria patients and mild malaria patients. Moreover, our results provide new insights into the potential effect of the dysregulation of gene expression in immune pathways. Host genetic variation may partly explain such alteration of gene expression. Further studies are required to investigate this in African populations

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Agroecology: Fostering improved access to land and natural resources

National audienceThis presentation discusses the experience of Gora Ndiaye, President of the Pan African Association of Gardens and the Ecological and Organic Agriculture Platform for Senegal and how an integrated agroforestry, agroecology and community supported agriculture can regenerate depleted soils and create incentives for youths to enter farming. The Agro-Ecological Farm School in Kaydara was established to address the challenges of villages being emptied of their youth, who move to the city or foreign countries. Young people no longer know how to live on their land where the soil is impoverished by monoculture conducted for decades and consequent erosion. The farmers are selling their land. Young people who want to stay in the village will soon be ‘landless’. The farm is located in the Fatick region, 150 km south of Dakar. It opened its doors in 2007 to welcome the first candidates for internship training. The action of the farm is to train farmers, young and old, women and men, in agroecological practices of diverse and complementary activities taking into account the necessity to restore soil fertility, protect the environment, and manage water. The registration criterion for a candidate to training was namely the ownership of at least one hectare of land. However this was not applicable at the opening of the training center. In order to resolve the case of young people without land ‘motivated’ by agroecology, land was acquired and allocated to those few young people at the start. The process has evolved since 2007 and gradually strategy has evolved: several mayors are now working with them to anchor agroecology in their land. Twenty young people from one same municipality were trained, and granted their 20 hectares of land with 80 hectares reserved by the Mayor council for future candidates. In another municipality 3 hectares were planned for the installation of 12 young people. In Fimela, where the farm is situated, local authorities have invested in the villages to explain the staffing approach of a hectare of land each young candidate following the training, so 20 hectares have been mobilized for 20 young people. The engagement with municipalities serves to accompany the youth as they develop their farms to help also contribute to reforestation of the commons: 10,000 coconut trees have been planted in 5 years. The choice of coconut is due to environmental and economic reasons: the coconut tree’s speed of growth, the shade it provides to understory plants, the sustainable production of the coconut’s economic value by use of all its parts (nuts, leaves, trunk), the brake it presents to marine erosion, its fibrous roots, its majestic beauty. The engagement with municipalities also supports women in the production of reproducible seeds. Young farmers are in internship for a period of 9 months to 2 years. During their training they are provided different capital necessary for their installation: » Land capital; » The vegetable capital: fruit trees (mainly coconut trees), forest trees, forage; » The wildlife capital: poultry, rabbits, or donkeys. According to the choice of young farmers; » The seed capital; » The capital of agro-ecological knowledge and technological knowledge; » Financial capital consists of the sales revenue of their productions (2/3 for students, 1/3 for the Farm School). They design their personal project for their farm and submit it to the end of their training period. This project was highlighted for its pertinence and consistence with the principles and objectives of agroecology as it contributes to promote youth employment and prevent rural depopulation, ensure food security or food sovereignty of families, improve living conditions and offer prospects, fight against desertification, land degradation and salinization, restore soil fertility and preserve biodiversity

Agroecology: Fostering improved access to land and natural resources

This presentation discusses the experience of Gora Ndiaye, President of the Pan African Association of Gardens and the Ecological and Organic Agriculture Platform for Senegal and how an integrated agroforestry, agroecology and community supported agriculture can regenerate depleted soils and create incentives for youths to enter farming. The Agro-Ecological Farm School in Kaydara was established to address the challenges of villages being emptied of their youth, who move to the city or foreign countries. Young people no longer know how to live on their land where the soil is impoverished by monoculture conducted for decades and consequent erosion. The farmers are selling their land. Young people who want to stay in the village will soon be ‘landless’. The farm is located in the Fatick region, 150 km south of Dakar. It opened its doors in 2007 to welcome the first candidates for internship training. The action of the farm is to train farmers, young and old, women and men, in agroecological practices of diverse and complementary activities taking into account the necessity to restore soil fertility, protect the environment, and manage water. The registration criterion for a candidate to training was namely the ownership of at least one hectare of land. However this was not applicable at the opening of the training center. In order to resolve the case of young people without land ‘motivated’ by agroecology, land was acquired and allocated to those few young people at the start. The process has evolved since 2007 and gradually strategy has evolved: several mayors are now working with them to anchor agroecology in their land. Twenty young people from one same municipality were trained, and granted their 20 hectares of land with 80 hectares reserved by the Mayor council for future candidates. In another municipality 3 hectares were planned for the installation of 12 young people. In Fimela, where the farm is situated, local authorities have invested in the villages to explain the staffing approach of a hectare of land each young candidate following the training, so 20 hectares have been mobilized for 20 young people. The engagement with municipalities serves to accompany the youth as they develop their farms to help also contribute to reforestation of the commons: 10,000 coconut trees have been planted in 5 years. The choice of coconut is due to environmental and economic reasons: the coconut tree’s speed of growth, the shade it provides to understory plants, the sustainable production of the coconut’s economic value by use of all its parts (nuts, leaves, trunk), the brake it presents to marine erosion, its fibrous roots, its majestic beauty. The engagement with municipalities also supports women in the production of reproducible seeds. Young farmers are in internship for a period of 9 months to 2 years. During their training they are provided different capital necessary for their installation: » Land capital; » The vegetable capital: fruit trees (mainly coconut trees), forest trees, forage; » The wildlife capital: poultry, rabbits, or donkeys. According to the choice of young farmers; » The seed capital; » The capital of agro-ecological knowledge and technological knowledge; » Financial capital consists of the sales revenue of their productions (2/3 for students, 1/3 for the Farm School). They design their personal project for their farm and submit it to the end of their training period. This project was highlighted for its pertinence and consistence with the principles and objectives of agroecology as it contributes to promote youth employment and prevent rural depopulation, ensure food security or food sovereignty of families, improve living conditions and offer prospects, fight against desertification, land degradation and salinization, restore soil fertility and preserve biodiversity

Evaluating the Social Impacts of Eco- and Ethical Fish Labeling on Small-scale Producers in Senegal

This paper provides an overview of ongoing work undertaken in Senegal to understand the implications of fisheries certification on the octopus value-chain. It analyses the opportunities to increase social and economic benefits for poorer groups and to establish a more gender sensitive approach to eco labelling through the implementation of upgrading strategies addressing equity gaps. It will describe the octopus value chain and give details on how the introduction of certification, such as an eco- or ethical fish label, may affect different actors in the chain and their ability to capture benefits. Over the past few years there has been a large increase in the interest for eco- and fair trade labelled produce, and there is increasing interest both by the fisheries themselves to gain market access and by international buyers who are keen to protect their reputation on responsible sourcing. While there are a number of potential benefits of certification including a promotion of sustainable fisheries management and increased investment in development, there are also a number of challenges, potential unintended consequences and social and economic elements that will not be addressed by certification. For instance, octopus certification is constrained by the limited number of countries exported to and the interest of buyers to produce certified and ethical labelled octopus. This research provides an analysis of the key issues in Senegal related to the proposed octopus certification. It also proposes responses to encourage a pro-poor and gender sensitive approach through supporting upgrading strategies that will be explored within the ongoing project

Agroecology: Fostering improved access to land and natural resources

This presentation discusses the experience of Gora Ndiaye, President of the Pan African Association of Gardens and the Ecological and Organic Agriculture Platform for Senegal and how an integrated agroforestry, agroecology and community supported agriculture can regenerate depleted soils and create incentives for youths to enter farming. The Agro-Ecological Farm School in Kaydara was established to address the challenges of villages being emptied of their youth, who move to the city or foreign countries. Young people no longer know how to live on their land where the soil is impoverished by monoculture conducted for decades and consequent erosion. The farmers are selling their land. Young people who want to stay in the village will soon be ‘landless’. The farm is located in the Fatick region, 150 km south of Dakar. It opened its doors in 2007 to welcome the first candidates for internship training. The action of the farm is to train farmers, young and old, women and men, in agroecological practices of diverse and complementary activities taking into account the necessity to restore soil fertility, protect the environment, and manage water. The registration criterion for a candidate to training was namely the ownership of at least one hectare of land. However this was not applicable at the opening of the training center. In order to resolve the case of young people without land ‘motivated’ by agroecology, land was acquired and allocated to those few young people at the start. The process has evolved since 2007 and gradually strategy has evolved: several mayors are now working with them to anchor agroecology in their land. Twenty young people from one same municipality were trained, and granted their 20 hectares of land with 80 hectares reserved by the Mayor council for future candidates. In another municipality 3 hectares were planned for the installation of 12 young people. In Fimela, where the farm is situated, local authorities have invested in the villages to explain the staffing approach of a hectare of land each young candidate following the training, so 20 hectares have been mobilized for 20 young people. The engagement with municipalities serves to accompany the youth as they develop their farms to help also contribute to reforestation of the commons: 10,000 coconut trees have been planted in 5 years. The choice of coconut is due to environmental and economic reasons: the coconut tree’s speed of growth, the shade it provides to understory plants, the sustainable production of the coconut’s economic value by use of all its parts (nuts, leaves, trunk), the brake it presents to marine erosion, its fibrous roots, its majestic beauty. The engagement with municipalities also supports women in the production of reproducible seeds. Young farmers are in internship for a period of 9 months to 2 years. During their training they are provided different capital necessary for their installation: » Land capital; » The vegetable capital: fruit trees (mainly coconut trees), forest trees, forage; » The wildlife capital: poultry, rabbits, or donkeys. According to the choice of young farmers; » The seed capital; » The capital of agro-ecological knowledge and technological knowledge; » Financial capital consists of the sales revenue of their productions (2/3 for students, 1/3 for the Farm School). They design their personal project for their farm and submit it to the end of their training period. This project was highlighted for its pertinence and consistence with the principles and objectives of agroecology as it contributes to promote youth employment and prevent rural depopulation, ensure food security or food sovereignty of families, improve living conditions and offer prospects, fight against desertification, land degradation and salinization, restore soil fertility and preserve biodiversity