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Publications (3)13.35 Total impact

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    Article: Human papillomavirus infection and cervical cytology in HIV-infected and HIV-uninfected Rwandan women.
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    ABSTRACT: Data on human papillomavirus (HPV) prevalence are essential for developing cost-effective cervical cancer prevention programs. In 2005, 710 human immunodeficiency virus (HIV)-positive and 226 HIV-negative Rwandan women enrolled in an observational prospective cohort study. Sociodemographic data, CD4+ cell counts, and cervical specimens were obtained. Cervicovaginal lavage specimens were collected from each woman and tested for >40 HPV types by a polymerase chain reaction assay; HPV types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68 were considered primary carcinogenic HPV types. The prevalence of HPV was higher in HIV-positive women than in HIV-negative women in all age groups. Among HIV-infected women, 69% were positive for >or=1 HPV type, 46% for a carcinogenic HPV type, and 10% for HPV-16. HPV prevalence peaked at 75% in the HIV-positive women aged 25-34 years and then declined with age to 37.5% in those >or=55 years old (Ptrend<.001). A significant trend of higher prevalence of HPV and carcinogenic HPV with lower CD4+ cell counts and increasing cytologic severity was seen among HIV-positive women. We found a higher prevalence of HPV infection in HIV-positive than in HIV-negative Rwandan women, and the prevalence of HPV and carcinogenic HPV infection decreased with age.
    The Journal of Infectious Diseases 06/2009; 199(12):1851-61. · 6.41 Impact Factor
  • Article: Genetic analysis of Rwandan patients with cystic fibrosis-like symptoms: identification of novel cystic fibrosis transmembrane conductance regulator and epithelial sodium channel gene variants.
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    ABSTRACT: The defect in chloride and sodium transport in cystic fibrosis (CF) patients is a consequence of CF transmembrane conductance regulator (CFTR) loss of function and an abnormal interaction between CFTR and the epithelial sodium channel (ENaC). A few patients were described with CF-like symptoms, a single CFTR mutation, and an ENaC mutation. 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 denaturing high-performance liquid chromatography followed by direct sequencing; whereas, the sodium channel non-voltage-gated 1 alpha (SCNN1A), sodium channel non-voltage-gated 1 beta (SCNN1B), and sodium channel non-voltage-gated 1 gamma (SCNN1G) subunits of the 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. 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 five patients detected the following eight 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 and 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. Our data suggest that CF-like syndrome in Africa could be associated with CFTR and ENaC mutations.
    Chest 11/2008; 135(5):1233-42. · 5.25 Impact Factor
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    Article: Neonatal screening for sickle cell disease in Central Africa: a study of 1825 newborns with a new enzyme-linked immunosorbent assay test.
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    ABSTRACT: To evaluate the feasibility of systematic neonatal screening for sickle cell disease in the region of Great Lakes in Central Africa using a new approach with limited costs. Between July 2004 and July 2006, 1825 newborn dried blood samples were collected onto filter papers in four maternity units from Burundi, Rwanda and the East of the Democratic Republic of Congo. We tested for the presence of haemoglobin C and S in the eluted blood by an enzyme-linked immunosorbent assay (ELISA) test using a monoclonal antibody. All ELISA-positive samples (multiple of the median (MoM) > or = 1.5) were confirmed by a simple molecular test. The statistica software version 7.1 was used to create graphics and to fix the MoM cut-off, and the chi(2) of Pearson was used to compare the genotype incidences between countries. Of the 1825 samples screened, 97 (5.32%) were positive. Of these, 60 (3.28%) samples were heterozygous for Hb S, and four (0.22%) for Hb C; two (0.11%) newborns were Hb SS homozygotes. The lower cost and the high specificity of ELISA test are appropriate for developing countries, and such systematic screening for sickle cell anaemia is therefore feasible.
    Journal of Medical Screening 01/2007; 14(3):113-6. · 1.69 Impact Factor