Browsing by Autor "Simonne De Doncker"

Now showing 1 - 8 of 8

A new focus of cutaneous leishmaniasis due to Leishmania amazonensis in a Sub Andean region of Bolivia
(Elsevier BV, 1998) Eliana C. Martinez; François Le Pont; M Torrez; Jenny Telleria; Fernando Regla Vargas; M Muñoz; Simonne De Doncker; Jean‐Claude Dujardin; Jean‐Pierre Dujardin
American tegumentary leishmaniasis: antigen-gene polymorphism, taxonomy and clinical pleomorphism
(Elsevier BV, 2004) Ana Lineth García; A. Kindt; Kelly Wilber Quispe‐Tintaya; Harry Bermudez; Alejandro Llanos‐Chea; Jorge Arévalo; Anne‐Laure Bañuls; Simonne De Doncker; D. Le Ray; Jean‐Claude Dujardin
American tegumentary leishmaniasis: direct species identification of Leishmania in non-invasive clinical samples
(Oxford University Press, 2006) Ana Lineth García; Rudy Parrado; Simonne De Doncker; Hernán Bermúdez; Jean‐Claude Dujardin
Species identification is highly relevant for improved prognosis and adequate treatment of American tegumentary leishmaniasis (ATL). PCR-based methods are available for this purpose but should be simplified to improve accessibility. As a first step in this process, this paper describes a simplified protocol for collection of clinical samples. Using samples from 44 Bolivian patients with confirmed ATL, we demonstrated that hsp70 PCR-RFLP on skin scrapings collected with a tooth pick allowed identification of the parasite species with a sensitivity of 95% and specificity of 100%. Our method should greatly facilitate individual patient management and epidemiological surveillance of ATL.
Association of the Endobiont Double-Stranded RNA Virus LRV1 With Treatment Failure for Human Leishmaniasis Caused byLeishmania braziliensisin Peru and Bolivia
(Oxford University Press, 2015) Vanessa Adaui; Lon‐Fye Lye; Natalia S. Akopyants; Mirko Zimic; Alejandro Llanos‐Cuentas; Lineth García; Ilse Maes; Simonne De Doncker; Deborah E. Dobson; Jorge Arévalo
Cutaneous and mucosal leishmaniasis, caused in South America by Leishmania braziliensis, is difficult to cure by chemotherapy (primarily pentavalent antimonials [Sb(V)]). Treatment failure does not correlate well with resistance in vitro, and the factors responsible for treatment failure in patients are not well understood. Many isolates of L. braziliensis (>25%) contain a double-stranded RNA virus named Leishmaniavirus 1 (LRV1), which has also been reported in Leishmania guyanensis, for which an association with increased pathology, metastasis, and parasite replication was found in murine models. Here we probed the relationship of LRV1 to drug treatment success and disease in 97 L. braziliensis-infected patients from Peru and Bolivia. In vitro cultures were established, parasites were typed as L. braziliensis, and the presence of LRV1 was determined by reverse transcription-polymerase chain reaction, followed by sequence analysis. LRV1 was associated significantly with an increased risk of treatment failure (odds ratio, 3.99; P = .04). There was no significant association with intrinsic Sb(V) resistance among parasites, suggesting that treatment failure arises from LRV1-mediated effects on host metabolism and/or parasite survival. The association of LRV1 with clinical drug treatment failure could serve to guide more-effective treatment of tegumentary disease caused by L. braziliensis.
In vitro promastigote fitness of putative Leishmania (Viannia) braziliensis/Leishmania (Viannia) peruviana hybrids
(Elsevier BV, 1999) Mary Cruz Torrico; Simonne De Doncker; Jorge Arévalo; D. Le Ray; Jean‐Claude Dujardin
Karyotype plasticity in NeotropicalLeishmania: an index for measuring genomic distance amongL. (V.) peruvianaandL. (V.) braziliensispopulations
(Cambridge University Press, 1995) Jean‐Claude Dujardin; Jean‐Pierre Dujardin; Michel Tibayrenc; G. Timperman; Simonne De Doncker; D. Jacquet; Jorge Arévalo; Alejandro Llanos‐Cuentas; Humberto Guerra; Harry Bermudez
A method for phenetic analysis of karyotype data has been developed for Leishmania populations. Measurement of size difference between chromosomes recognized by a given DNA probe in different isolates led to the formulation of a Chromosome Size Difference Index (CSDI). The method was applied to phenetic analysis of 4 sets of chromosomes--each set being recognized by a different probe--in 37 L. (Viannia) peruviana isolates sampled along a North-South transect through the Peruvian Andes and, in 11 L. (V.) braziliensis isolates from the Amazonian forest (Peru, Bolivia and Brazil). Karyotype variability was better accounted for by CSDI than by a method based on disjunctive encoding of karyotype data. CSDI evidenced the nature of relationships between L. braziliensis and L. peruviana and it provided a coherent picture of geographical and genomic differentiation among parasite populations. The latter did cluster according to their geographical origin. L. braziliensis was found karyotypically more homogeneous than L. peruviana. Within L. peruviana, Northern populations were closer to L. braziliensis than to Southern L. peruviana populations. The validity of karyotypic populations, or karyodemes, was sustained.
Leishmaniasis in the Lowlands of Bolivia (Leishbol): Part III. Status of the Disease in an Area of Spontaneous Agricultural Colonization
(1989) M. Recacoechea; G Villarroel; S. Balderrama; R. Urjel; Simonne De Doncker; D. Jacquet; D. Le Ray
Leishmaniasis in the Lowlawnds of Bolivia (Leishbol): Part VIII. Characterization and Identification of Bolivian Isolates by PFG Karyotyping
(1989) J. Cl. Dujardin; Nadesan Gajendran; R. Hamers; G. Matthijsen; R. Urjel; M. Recacoechea; G Villarroel; Harry Bermudez; P. Desjeux; Simonne De Doncker