186 research outputs found

    Insecticide-treated curtains reduce the prevalence and intensity of malaria infection in Burkina Faso

    Get PDF
    A large, randomized controlled trial to investigate the impact of insecticide-treated curtains (ITC) on child mortality was conducted in an area of seasonal, holoendemic malaria in Burkina Faso. 158 communities totalling some 90,000 people were censused and grouped into 16 geographical clusters, 8 of which were randomly selected to receive ITC in June-July 1994, just prior to the rainy season. In September-October 1995, at the peak period of malaria transmission, a cross-sectional survey was conducted in 84 of the villages. A random sample of 905 children aged 6-59 months was identified and visited. 763 children (84%) were present at the time of the visit and recruited into the study. Mothers were asked about fever in the past 24 h, the child's temperature was taken, and a sample of blood collected to identify and quantify malaria infections and to measure haemoglobin (Hb) levels. Children protected by ITC were less likely to be infected with Plasmodium falciparum (risk ratio = 0.92; 95% CI 0.86, 0.98) or P. malariae (risk ratio = 0.42, 95% CI 0.19, 0.95). The mean intensity of P. falciparum infections was lower among children protected by ITC (899 vs. 1583 trophozoites/microliter; P < 0.001), while the mean Hb level was 0.4 g/dl higher (P < 0.001). While we found no evidence that ITC had an impact on the prevalence of malaria-associated fever episodes, the confidence intervals around our estimates of the impact of ITC on malaria morbidity were wide. We conclude that widespread implementation of ITC in this area of high malaria transmission led to a modest reduction in the prevalence of malaria infection and to a more substantial reduction in the intensity of these infections which caused increased Hb levels. We were unable to demonstrate any impact of ITC on malaria morbidity, but the wide confidence intervals around our point estimates do not preclude the possibility of a substantial impact

    Child mortality in a West African population protected with insecticide-treated curtains for a period of up to 6 years

    Get PDF
    Objectives To determine the impact of insecticide-treated curtains (ITC) on all-cause child mortality (6–59 months) over a period of six years. To determine whether initial reductions in child mortality following the implementation of ITC are sustained over the longer term or whether “delayed” mortality occurs. Methods A rural population of ca 100 000 living in an area with high, seasonal Plasmodium falciparum transmission was studied in Burkina Faso. Annual censuses were conducted from 1993 to 2000 to measure child mortality. ITC to cover doors, windows, and eaves were provided to half the population in 1994 with the remainder receiving ITC in 1996. Curtains were re-treated or, if necessary, replaced annually. Findings Over six years of implementation of ITC, no evidence of the shift in child mortality from younger to older children was observed. Estimates of the reduction in child mortality associated with ITC ranged from 19% to 24%. Conclusions In our population there was no evidence to suggest that initial reduction in child mortality associated with the introduction of insecticide-treated materials was subsequently compromised by a shift in child mortality to older-aged children. Estimates of the impact of ITC on child mortality in this population range from 19% to 24%. Keywords Malaria/epidemiology/mortality; Bedding and linens/utilization/statistics; Child, Preschool; Infant mortality; Plasmodium falciparum/immunology; Malaria, Falciparum/prevention and control/transmission; Anopheles; Mosquito control; Permethrin; Remission induction; Age factors; Regression analysis; Incidence; Survival rate; Randomized controlled trials; Burkina Faso/epidemiology (source: MeSH, NLM). Mots clĂ©s Paludisme/Ă©pidĂ©miologie/mortalitĂ©; Literie et linge/utilisation/statistique; Enfant Ăąge prĂ©-scolaire; MortalitĂ© nourrisson; Plasmodium falciparum/immunologie; Paludisme plasmodium falciparum/prĂ©vention et contrĂŽle/transmission; AnophĂšles; Lutte contre moustique; PermĂ©thrine; Traitement induction rĂ©mission; Facteur Ăąge; Analyse rĂ©gression; Incidence; Taux survie; Essai clinique randomisĂ©; Burkina Faso/Ă©pidĂ©miologie (source: MeSH, INSERM). Palabras clave Paludismo/epidemiologĂ­a/mortalidad; Ropa de cama y ropa blanca/utilizaciĂłn/estadĂ­stica; Infante; Mortalidad infantil; Plasmodium falciparum/inmunologĂ­a; Paludismo falciparum/prevenciĂłn y control/ transmisiĂłn; Anopheles; Control de mosquitos; Permetrina; InducciĂłn de remisiĂłn; Factores de edad; AnĂĄlisis de regresiĂłn; Incidencia; Tasa de supervivencia; Ensayos controlados aleatorios; Burkina Faso/epidemiologĂ­a (fuente: DeCS, BIREME). Bulletin of the World Health Organization 2004;82:85-91

    Task sharing for family planning services, Burkina Faso

    Full text link
    © 2019, World Health Organization. All rights reserved. Problem In Burkina Faso, the coverage of services for family planning is low due to shortage of qualified health staff and limited access to services. Approach Following the launch of the Ouagadougou Partnership, an alliance to catalyse the expansion of family planning services, the health ministry created a consortium of family planning stakeholders in 2011. The consortium adopted a collaborative framework to implement a pilot project for task sharing in family planning at community and primary health-care centre levels in two rural districts. Stakeholders were responsible for their areas of expertise. These areas included advocacy; monitoring and evaluation; and capacity development of community health workers (CHWs) to offer oral and injectable contraceptives to new users and of auxiliary nurses and auxiliary midwives to provide implants and intrauterine devices. The health ministry implemented supportive supervision cascades involving relevant planning and service levels. Local setting In Burkina Faso, only 15% (2563/17 087) of married women used modern contraceptives in 2010. Relevant changes Adoption of new policies and clinical care standards expanded task sharing roles in family planning. The consortium trained a total of 79 CHWs and 124 auxiliary nurses and midwives. Between January 2017 and December 2018, CHWs provided injectables to 3698 new users, and auxiliary nurses or midwives provided 726 intrauterine devices and 2574 implants to new users. No safety issues were reported. Lessons learnt The pilot project was feasible and safe, however, financial constraints are hindering scale-up efforts. Supportive supervision cascades were critical in ensuring success

    Dnmt2/Trdmt1 as mediator of RNA polymerase II transcriptional activity in cardiac growth

    Get PDF
    Dnmt2/Trdmt1 is a methyltransferase, which has been shown to methylate tRNAs. Deficient mutants were reported to exhibit various, seemingly unrelated, defects in development and RNA-mediated epigenetic heredity. Here we report a role in a distinct developmental regulation effected by a noncoding RNA. We show that Dnmt2-deficiency in mice results in cardiac hypertrophy. Echocardiographic measurements revealed that cardiac function is preserved notwithstanding the increased dimensions of the organ due to cardiomyocyte enlargement. Mechanistically, activation of the P-TEFb complex, a critical step for cardiac growth, results from increased dissociation of the negatively regulating Rn7sk non-coding RNA component in Dnmt2-deficient cells. Our data suggest that Dnmt2 plays an unexpected role for regulation of cardiac growth by modulating activity of the P-TEFb complex. © 2016 Ghanbarian et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

    Modern insulation materials for warming of walls

    Get PDF
    Biodiversity hotspots understandably attract considerable conservation attention. However, deserts are rarely viewed as conservation priority areas, due to their relatively low productivity, yet these systems are home to unique species, adapted to harsh and highly variable environments. While global attention has been focused on hotspots, the world's largest tropical desert, the Sahara, has suffered a catastrophic decline in megafauna. Of 14 large vertebrates that have historically occurred in the region, four are now extinct in the wild, including the iconic scimitar-horned oryx (Oryx dammah). The majority has disappeared from more than 90% of their Saharan range, including addax (Addax nasomaculatus), dama gazelle (Nanger dama) and Saharan cheetah (Acinonyx jubatus hecki) - all now on the brink of extinction. Greater conservation support and scientific attention for the region might have helped to avert these catastrophic declines. The Sahara serves as an example of a wider historical neglect of deserts and the human communities who depend on them. The scientific community can make an important contribution to conservation in deserts by establishing baseline information on biodiversity and developing new approaches to sustainable management of desert species and ecosystems. Such approaches must accommodate mobility of both people and wildlife so that they can use resources most efficiently in the face of low and unpredictable rainfall. This is needed to enable governments to deliver on their commitments to halt further degradation of deserts and to improve their status for both biodiversity conservation and human well-being. Only by so-doing will deserts be able to support resilient ecosystems and communities that are best able to adapt to climate change. © 2013 John Wiley & Sons Ltd

    Assessment of the Food Habits of the Moroccan Dorcas Gazelle in M’Sabih Talaa, West Central Morocco, Using the trnL Approach

    Get PDF
    Food habits of the Moroccan dorcas gazelle, Gazella dorcas massaesyla, previously investigated in the 1980s using microhistological fecal analysis, in the M’Sabih Talaa Reserve, west central Morocco, were re-evaluated over three seasons (spring, summer and autumn 2009) using the trnL approach to determine the diet composition and its seasonal variation from fecal samples. Taxonomic identification was carried out using the identification originating from the database built from EMBL and the list of plant species within the reserve. The total taxonomic richness in the reserve was 130 instead of 171 species in the 1980s. The diet composition revealed to be much more diversified (71 plant taxa belonging to 57 genus and 29 families) than it was 22 years ago (29 identified taxa). Thirty-four taxa were newly identified in the diet while 13 reported in 1986–87 were not found. Moroccan dorcas gazelle showed a high preference to Acacia gummifera, Anagallis arvensis, Glebionis coronaria, Cladanthus arabicus, Diplotaxis tenuisiliqua, Erodium salzmannii, Limonium thouini, Lotus arenarius and Zizyphus lotus. Seasonal variations occurred in both number (40–41 taxa in spring-summer and 49 taxa in autumn vs. respectively 23–22 and 26 in 1986–1987) and taxonomic type of eaten plant taxa. This dietary diversification could be attributed either to the difference in methods of analysis, trnL approach having a higher taxonomic resolution, or a potential change in nutritional quality of plants over time

    Development of a new version of the Liverpool Malaria Model. II. Calibration and validation for West Africa

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>In the first part of this study, an extensive literature survey led to the construction of a new version of the <it>Liverpool Malaria Model </it>(LMM). A new set of parameter settings was provided and a new development of the mathematical formulation of important processes related to the vector population was performed within the LMM. In this part of the study, so far undetermined model parameters are calibrated through the use of data from field studies. The latter are also used to validate the new LMM version, which is furthermore compared against the original LMM version.</p> <p>Methods</p> <p>For the calibration and validation of the LMM, numerous entomological and parasitological field observations were gathered for West Africa. Continuous and quality-controlled temperature and precipitation time series were constructed using intermittent raw data from 34 weather stations across West Africa. The meteorological time series served as the LMM data input. The skill of LMM simulations was tested for 830 different sets of parameter settings of the undetermined LMM parameters. The model version with the highest skill score in terms of entomological malaria variables was taken as the final setting of the new LMM version.</p> <p>Results</p> <p>Validation of the new LMM version in West Africa revealed that the simulations compare well with entomological field observations. The new version reproduces realistic transmission rates and simulated malaria seasons are comparable to field observations. Overall the new model version performs much better than the original model. The new model version enables the detection of the epidemic malaria potential at fringes of endemic areas and, more importantly, it is now applicable to the vast area of malaria endemicity in the humid African tropics.</p> <p>Conclusions</p> <p>A review of entomological and parasitological data from West Africa enabled the construction of a new LMM version. This model version represents a significant step forward in the modelling of a weather-driven malaria transmission cycle. The LMM is now more suitable for the use in malaria early warning systems as well as for malaria projections based on climate change scenarios, both in epidemic and endemic malaria areas.</p

    Exploring Functional ÎČ-Cell Heterogeneity In Vivo Using PSA-NCAM as a Specific Marker

    Get PDF
    BACKGROUND:The mass of pancreatic beta-cells varies according to increases in insulin demand. It is hypothesized that functionally heterogeneous beta-cell subpopulations take part in this process. Here we characterized two functionally distinct groups of beta-cells and investigated their physiological relevance in increased insulin demand conditions in rats. METHODS:Two rat beta-cell populations were sorted by FACS according to their PSA-NCAM surface expression, i.e. beta(high) and beta(low)-cells. Insulin release, Ca(2+) movements, ATP and cAMP contents in response to various secretagogues were analyzed. Gene expression profiles and exocytosis machinery were also investigated. In a second part, beta(high) and beta(low)-cell distribution and functionality were investigated in animal models with decreased or increased beta-cell function: the Zucker Diabetic Fatty rat and the 48 h glucose-infused rat. RESULTS:We show that beta-cells are heterogeneous for PSA-NCAM in rat pancreas. Unlike beta(low)-cells, beta(high)-cells express functional beta-cell markers and are highly responsive to various insulin secretagogues. Whereas beta(low)-cells represent the main population in diabetic pancreas, an increase in beta(high)-cells is associated with gain of function that follows sustained glucose overload. CONCLUSION:Our data show that a functional heterogeneity of beta-cells, assessed by PSA-NCAM surface expression, exists in vivo. These findings pinpoint new target populations involved in endocrine pancreas plasticity and in beta-cell defects in type 2 diabetes

    Mysid crustaceans as standard models for the screening and testing of endocrine-disrupting chemicals

    Get PDF
    Author Posting. © Springer, 2007. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Ecotoxicology 16 (2007): 205-219, doi:10.1007/s10646-006-0122-0.Investigative efforts into the potential endocrine-disrupting effects of chemicals have mainly concentrated on vertebrates, with significantly less attention paid to understanding potential endocrine disruption in the invertebrates. Given that invertebrates account for at least 95% of all known animal species and are critical to ecosystem structure and function, it remains essential to close this gap in knowledge and research. The lack of progress regarding endocrine disruption in invertebrates is still largely due to: (1) our ignorance of mode-of-action, physiological control, and hormone structure and function in invertebrates; (2) lack of a standardized invertebrate assay; (3) the irrelevance to most invertebrates of the proposed activity-based biological indicators for endocrine disruptor exposure (androgen, estrogen and thyroid); (4) limited field studies. Past and ongoing research efforts using the standard invertebrate toxicity test model, the mysid shrimp, have aimed at addressing some of these issues. The present review serves as an update to a previous publication on the use of mysid shrimp for the evaluation of endocrine disruptors (Verslycke et al., 2004a). It summarizes recent investigative efforts that have significantly advanced our understanding of invertebrate-specific endocrine toxicity, population modeling, field studies, and transgeneration standard test development using the mysid model.Supported by a Fellowship of the Belgian American Educational Foundation
    • 

    corecore