25 research outputs found

    Species diversity and distribution of ruderal flora on landfills in Maradi city, Niger

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    Waste management continues to be a critical environmental issue in cities. It impacts on the well being of the population, the environment and the biodiversity. In the city of Maradi, in Niger, more interest is given to the problem in order to understand the whole waste management system. It is in this context that this study is carried out to investigate on the role of ruderal flora on the municipal solid wastes dumpsites and landfill sites in Maradi city. The specific objectives are to determine the floristic diversity and distribution of ruderal flora on the municipal solid waste disposal sites, and to identify potential species that can play an important role in the phytoremediation of these sites. In total, 65 species belonging to 52 genera and 24 families were recorded. These species can be categorised into two groups containing anthropic and nitrophilic species according to the ascending Hierarchical Classification (AHC) at 25% similarity. Characteristic species of the first group G1 are Amaranthus viridis and Cucurbita pepo, and Datura innoxia and Cucumis melo for the second group G2. Other ruderal species, namely Amaranthus spinosus L., Amaranthus viridis L., Celosia trygina L., Datura innoxia Mill., and an introduced woody species, Cuphea hyssopifolia Kunth., found are not included in the Maradi city list of species. Datura innoxia, Amaranthus viridis and Amaranthus spinosus are species known to tolerate different degrees of pollution and their ecology should be further study to better understand how they can be used for phytoremediation on this kind of sites

    Etiology and factors associated with pneumonia in children under 5 years of age in Mali: A prospective case-control study

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    Background: There are very limited data on children with pneumonia in Mali. The objective was to assess the etiology and factors associated with community-acquired pneumonia in hospitalized children <5 years of age in Mali. Methods: A prospective hospital-based case-control study

    Colonization Density of the Upper Respiratory Tract as a Predictor of Pneumonia-Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, and Pneumocystis jirovecii.

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    BACKGROUND.: There is limited information on the association between colonization density of upper respiratory tract colonizers and pathogen-specific pneumonia. We assessed this association for Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, and Pneumocystis jirovecii. METHODS.: In 7 low- and middle-income countries, nasopharyngeal/oropharyngeal swabs from children with severe pneumonia and age-frequency matched community controls were tested using quantitative polymerase chain reaction (PCR). Differences in median colonization density were evaluated using the Wilcoxon rank-sum test. Density cutoffs were determined using receiver operating characteristic curves. Cases with a pathogen identified from lung aspirate culture or PCR, pleural fluid culture or PCR, blood culture, and immunofluorescence for P. jirovecii defined microbiologically confirmed cases for the given pathogens. RESULTS.: Higher densities of H. influenzae were observed in both microbiologically confirmed cases and chest radiograph (CXR)-positive cases compared to controls. Staphylococcus aureus and P. jirovecii had higher densities in CXR-positive cases vs controls. A 5.9 log10 copies/mL density cutoff for H. influenzae yielded 86% sensitivity and 77% specificity for detecting microbiologically confirmed cases; however, densities overlapped between cases and controls and positive predictive values were poor (<3%). Informative density cutoffs were not found for S. aureus and M. catarrhalis, and a lack of confirmed case data limited the cutoff identification for P. jirovecii. CONCLUSIONS.: There is evidence for an association between H. influenzae colonization density and H. influenzae-confirmed pneumonia in children; the association may be particularly informative in epidemiologic studies. Colonization densities of M. catarrhalis, S. aureus, and P. jirovecii are unlikely to be of diagnostic value in clinical settings

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

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    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

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Pharmacological Approaches for the Modulation of the Potassium Channel KV4.x and KChIPs

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    Ion channels are macromolecular complexes present in the plasma membrane and intracellular organelles of cells. Dysfunction of ion channels results in a group of disorders named channelopathies, which represent an extraordinary challenge for study and treatment. In this review, we will focus on voltage-gated potassium channels (KV), specifically on the KV4-family. The activation of these channels generates outward currents operating at subthreshold membrane potentials as recorded from myocardial cells (ITO, transient outward current) and from the somata of hippocampal neurons (ISA). In the heart, KV4 dysfunctions are related to Brugada syndrome, atrial fibrillation, hypertrophy, and heart failure. In hippocampus, KV4.x channelopathies are linked to schizophrenia, epilepsy, and Alzheimer’s disease. KV4.x channels need to assemble with other accessory subunits (β) to fully reproduce the ITO and ISA currents. β Subunits affect channel gating and/or the traffic to the plasma membrane, and their dysfunctions may influence channel pharmacology. Among KV4 regulatory subunits, this review aims to analyze the KV4/KChIPs interaction and the effect of small molecule KChIP ligands in the A-type currents generated by the modulation of the KV4/KChIP channel complex. Knowledge gained from structural and functional studies using activators or inhibitors of the potassium current mediated by KV4/KChIPs will better help understand the underlying mechanism involving KV4-mediated-channelopathies, establishing the foundations for drug discovery, and hence their treatments.Ministerio de Ciencia e Innovacion (MICIU) Spain SAF201675021-R PID2019-104366RB-C21 RTI2018-097189-B-C22 PID2019-104366RBC22Instituto de Salud Carlos III CIBERCV program CB/11/00222Consejo Superior de Investigaciones Cientificas (CSIC) PIE 201820E104 2019AEP148 201880E109European Fund for Economic and Regional Development (FEDER)Spanish Ministry of Economy, Industry, and Competitivity (MINECO)Consejo Superior de Investigaciones Cientificas (CSIC) BES-2017-080184 FPU2017/02731Department of Atomic Energy (DAE)CUNY Research Scholars ProgramCollegiate Science Technology Entry Program (CSTEP)Hostos Office of Academic AffairsCSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI

    Effects of polyphenols and lipids from Pennisetum glaucum grains on T-cell activation: modulation of Ca2+ and ERK1/ERK2 signaling

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    International audienceBACKGROUND: Pearl millet (PM), i.e., Pennisetum glaucum, is widely grown in Africa and known for its anti-oxidant and anti-hyperlipidemic properties.METHODS: The P. glaucum grains were obtained from the region of Ouled Aïssa (South of Algeria). We assessed the effects of phenolic compounds and lipids, extracted from seeds of P. glaucum, on rat lymphocyte proliferation, activated by phorbol 12-myristate 13-acetate and ionomycin. In order to explore signaling pathway, triggered by these compounds, we assessed interleukin-2 (IL-2) mRNA expression and extracellular signal-regulated kinase-1/2 (ERK1/ERK2) phosphorylation. Finally, we determined increases in free intracellular Ca(2+) concentrations, [Ca(2+)]i, by employing Fura-2/AM in rat lymphocytes.RESULTS: The composition of P. glaucum grains in polyphenols was estimated to be 1660 µg gallic acid equivalents (GAE)/g. Lipids represented 4.5 %, and more than 72% of the fatty acids belonged to unsaturated family. Our investigation showed that both lipid and phenolic compounds inhibited mitogen-induced T-cell proliferation. Compared with phenolic compounds, lipids exerted weaker effects on ERK-1/ERK2 phosphorylation and Ca(2+) signaling in mitogen-activated T-cells.CONCLUSION: We conclude that the immunomodulatory effects of P. glaucum could be contributed by its phenolic and lipid contents
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