14 research outputs found
Insectes ravageurs et champignons parasites associés au dépérissement des peuplements de Tectona grandis (teck) régénérés à Téné, zone semi-décidue de Côte d’Ivoire
Les rejets de souche de teck sont l’objet d’attaque par des ravageurs et champignons capables de freiner leur croissance et développement. L’objectif est d’identifier les insectes ravageurs et les champignons parasites associés au dépérissement des rejets de teck régénérés à partir des souches. Au plan méthodologique, les ravageurs ont été caractérisés par repérage et exploration des dégâts corticaux et sous-corticaux des rejets de teck. Les champignons ont été isolés à partir des racines de rejets présentant des symptômes d’infection fongique. Les résultats ont mis en évidence la présence des termites (g. Ancistrotermes), des criquets puants (Zonocerus variegatus) et des coléoptères (Xyleborus aquilus). L’isolement et l’identification fongiques ont montré les espèces, Phellinus noxius, Fusarium verticilioides et les genres, Fusarium, Trichoderma, Penicillium et Aspergillus. Phellinus noxius, reconnu comme agent de pourriture brune racinaire provoque le dépérissement puis la mort des rejets de teck.© 2015 International Formulae Group. All rights reserved.Mots clés: Rejet de souche de teck, termites, criquets, coléoptères, champignons, dégâtsEnglish Title: Ravager insects and fungi associate to dieback of stand of Tectona grandis (teak) regenerate at Téné, semi deciduous zone of Côte d’IvoireEnglish AbstractSprouts of tools were attacked by ravagers and fungi capable to stop their growth and development. The objective of this work is to identify ravager insects and parasitizes fungi associate to dieback of sprouted from  tools of Teak. Methodologically, ravagers were characterized by search and exploration of cortical and subcortical damages of teak. Fungi were isolated from roots of sprout of stool presenting symptom of fungical infection. Results showed the presence of termites (g. Ancistrotermes), stinking crickets (Zonocerus variegatus) and beetles Xyleborus aquilus). Isolation and identification revealed the presence of fungal species Phellinus noxius, Fusarium verticilioides and genius, Fusarium, Trichoderma, Penicillium and Aspergillus. Phellinus noxius, known like agent of brown root rot incite dieback and sprouts death.© 2015 International Formulae Group. All rights reserved.Keywords: Sprouted from tools of teak, termites, crickets, beetles, fungi, damag
Pattern of congenital heart diseases in Rwandan children with genetic defects
Introduction: Congenital heart diseases (CHD) are commonly associated with genetic defects. Our study aimed at determining the occurrence and pattern of CHD association with genetic defects among pediatric patients in Rwanda.Methods: A total of 125 patients with clinical features suggestive of genetic defects were recruited. Echocardiography and standard karyotype studies were performed in all patients.Results: CHDs were detected in the majority of patients with genetic defects. The commonest isolated CHD was ventricular septal defect found in many cases of Down syndrome. In total, chromosomal abnormalities represented the majority of cases in our cohort and were associated with various types of CHDs.Conclusion: Our findings showed that CHDs are common in Rwandan pediatric patients with genetic defects. These results suggest that a routine echocardiography assessment combined with systematic genetic investigations including standard karyotype should be mandatory in patients presenting characteristic clinical features in whom CHD is suspected to be associated with genetic defect.Key words: Congenital heart disease, genetic defects, pediatric patients, Rwand
Assessment of soil degradation and chemical compositions in Rwandan tea-growing areas
This study has focused on the processes of soil degradation and chemical element concentration in tea-growing regions of Rwanda, Africa. Soil degradation accelerated by erosion is caused not only by topography but also by human activities. This soil degradation involves both the physical loss and reduction in the amount of topsoil associated with nutrient decline. Soil samples were collected from eleven tropical zones in Rwanda and from variable depth within each collecting site. Of these, Samples from three locations in each zone were analyzed in the laboratory, with the result that the pH of all soil samples is shown to be less than 5 (pH<5) with a general average of 4.4. The elements such as iron (Fe), copper (Cu), manganese (Mn), and zinc (Zn) are present in high concentration levels. In contrast calcium (Ca) and sodium (Na) are present at low-level concentrations and carbon (C) was found in minimal concentrations. In addition, elements derived from fertilizers, such as nitrogen (N), phosphorous (P), and potassium (K) which is also from minerals such as feldspar, are also present in low-level concentrations. The results indicate that the soil in certain Rwandan tea plantations is acidic and that this level of pH may help explain, in addition to natural factors, the deficiency of some elements such as Ca, Mg, P and N. The use of chemical fertilizers, land use system and the location of fields relative to household plots are also considered to help explain why tea plantation soils are typically degraded
Importance of local hypoxia on endothelial phenotype for an in vitro approach to bone marrow angiogenesis
International audienceThe vasculature of bone marrow differs from that in other organs, and its characteristics should be considered when exploring the medullar angiogenesis associated with hematological malignancies. We show here that the human bone marrow sinusoidal cell line HBME-1 has a specific expression pattern of angiogenic factors and receptors, characterized by a unique VEGFR3(+), Tie2(-) signature, that resembles the in vivo pattern. Moreover, the HBME-1 cultured for up to 3 days in hypoxic conditions, similar to those found in the bone marrow, specifically downregulated expression of VEGFR1, VEGFR2 and ETAR. Thus, a model using bone marrow sinusoidal cells cultured under reduced oxygen tension may be more relevant than classical in vitro endothelial cultures for understanding the interactions between endothelial and malignant cells in the medullar microenvironment
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Improving district facility readiness: a 12-month evaluation of a data-driven health systems strengthening intervention in rural Rwanda
Background: While health systems strengthening (HSS) interventions are recommended by global health policy experts to improve population health in resource-limited settings, few examples exist of evaluations of HSS interventions conducted at the district level. In 2009, a partnership between Partners In Health (PIH), a non-governmental organization, and the Rwandan Ministry of Health (RMOH) was provided funds to implement and evaluate a district-level HSS intervention in two rural districts of Rwanda. Design: The partnership provided limited funds to 14 health centers for targeted systems support in 2010; six others received support prior to the intervention (reference). RMOH health systems norms were mapped across the WHO HSS framework, scored from 0 to 10 and incorporated into a rapid survey assessing 11 domains of facility readiness. Stakeholder meetings allowed partnership leaders to review results, set priorities, and allocate resources. Investments included salary support, infrastructure improvements, medical equipment, and social support for patients. We compared facility domain scores from the start of the intervention to 12 months and tested for correlation between change in score and change in funding allocation to assess equity in our approach. Results: We found significant improvements among intervention facilities from baseline to 12 months across several domains [infrastructure (+4, p=0.0001), clinical services (+1.2, p=0.03), infection and sanitation control (+0.6, p=0.03), medical equipment (+1.0, p=0.02), information use (+2, p=0.002)]. Composite score across domains improved from 6.2 at baseline to 7.4 at 12 months (p=0.002). Across facilities, 50% had composite scores greater than the average score among reference facilities (7.4) at 12 months compared to none at baseline. Conclusions: Rapid facility surveys, stakeholder engagement, and information feedback can be used for gap analysis and resource allocation. This approach can achieve effective use of limited resources, improve facility readiness, and ensure consistency of facility capacity to provide quality care at the district level
Genetic Analysis of Rwandan Patients With Cystic Fibrosis-Like Symptoms: Identification of Novel Cystic Fibrosis Transmembrane Conductance Regulator and Epithelial Sodium Channel Gene Variants.
Background The defect in chloride and sodium transport in cystic fibrosis (CF) patients is a consequence of CFTR loss of function and of an abnormal interaction between CFTR and ENaC. A few patients were described with CF-like symptoms, a single CFTR mutation and an ENaC mutation. Methods To study African patients with CF-like symptoms and to relate the disease to gene mutations of both CFTR and ENaC genes, we collected clinical data and DNA samples from 60 African patients with a CF phenotype. The CFTR gene was first analyzed in all patients by dHPLC followed by direct sequencing, whereas the SCNN1A, SCNN1B and SCNN1G subunits of ENaC gene were analyzed by sequencing in the five patients who carried only one CF mutation. The frequency of all identified ENaC variants was established in a control group of 200 healthy individuals and in the 55 CF-like patients without any CFTR mutation Results Three CFTR mutants, including one previously undescribed missense mutation (p.A204T), and a 5T/7T variant were identified in five patients. ENaC gene sequencing in these 5 patients detected 8 ENaC variants: c.72T>C and p.V573I in SCNN1A; p.V348M, p.G442V, c.1473 + 28C>T, and p.T577T in SCNN1B; and p.S212S, c.1176 + 30G>C in SCNN1G. In the 55 CF-like patients without any CFTR mutation, we identified five of these eight ENaC variants, including the frequent p.G442V polymorphism, but we did not detect the presence of the p.V348M, p.T577T, and c.1176 + 30G>C ENaC variants. Moreover, these last three ENaC variants, p.V348M, p.T577T, and c.1176 + 30G>C, were not found in the control group. Conclusion Our data suggest that CF-like syndrome in Africa could be associated with CFTR and ENaC mutations
Pattern of congenital heart diseases in Rwandan children with genetic defects.
peer reviewedINTRODUCTION: Congenital heart diseases (CHD) are commonly associated with genetic defects. Our study aimed at determining the occurrence and pattern of CHD association with genetic defects among pediatric patients in Rwanda. METHODS: A total of 125 patients with clinical features suggestive of genetic defects were recruited. Echocardiography and standard karyotype studies were performed in all patients. RESULTS: CHDs were detected in the majority of patients with genetic defects. The commonest isolated CHD was ventricular septal defect found in many cases of Down syndrome. In total, chromosomal abnormalities represented the majority of cases in our cohort and were associated with various types of CHDs. CONCLUSION: Our findings showed that CHDs are common in Rwandan pediatric patients with genetic defects. These results suggest that a routine echocardiography assessment combined with systematic genetic investigations including standard karyotype should be mandatory in patients presenting characteristic clinical features in whom CHD is suspected to be associated with genetic defect