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1.
Parasit Vectors ; 8: 566, 2015 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-26515286

RESUMEN

Unfortunately, the original version of this article [1] contained an error. Figure 1 in the original article, corresponded to the first coinertia analysis that was carried out with no data on the procyclin PE repeats for the T. brucei brucei strains. After including these data, the coinertia analysis was modified both in the directionality of the arrows in the Y Hyperspace and in the biplot generated by the interaction of the two coinertia axes. The modified coinertia analysis is included in Fig. 1.

2.
Parasit Vectors ; 8: 536, 2015 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-26467019

RESUMEN

BACKGROUND: Livestock trypanosomoses, caused by three species of the Trypanozoon subgenus, Trypanosoma brucei brucei, T. evansi and T. equiperdum is widely distributed throughout the world and constitutes an important limitation for the production of animal protein. T. evansi and T. equiperdum are morphologically indistinguishable parasites that evolved from a common ancestor but acquired important biological differences, including host range, mode of transmission, distribution, clinical symptoms and pathogenicity. At a molecular level, T. evansi is characterized by the complete loss of the maxicircles of the kinetoplastic DNA, while T. equiperdum has retained maxicircle fragments similar to those present in T. brucei. T. evansi causes the disease known as Surra, Derrengadera or "mal de cadeiras", while T. equiperdum is the etiological agent of dourine or "mal du coit", characterized by venereal transmission and white patches in the genitalia. METHODS: Nine Venezuelan Trypanosoma spp. isolates, from horse, donkey or capybara were genotyped and classified using microsatellite analyses and maxicircle genes. The variables from the microsatellite data and the Procyclin PE repeats matrices were combined using the Hill-Smith method and compared to a group of T. evansi, T. equiperdum and T. brucei reference strains from South America, Asia and Africa using Coinertia analysis. Four maxicircle genes (cytb, cox1, a6 and nd8) were amplified by PCRfrom TeAp-N/D1 and TeGu-N/D1, the two Venezuelan isolates that grouped with the T. equiperdum STIB841/OVI strain. These maxicircle sequences were analyzed by nucleotide BLAST and aligned toorthologous genes from the Trypanozoon subgenus by MUSCLE tools. Phylogenetic trees were constructed using Maximum Parsimony (MP) and Maximum Likelihood (ML) with the MEGA5.1® software. RESULTS: We characterized microsatellite markers and Procyclin PE repeats of nine Venezuelan Trypanosoma spp. isolates with various degrees of virulence in a mouse model, and compared them to a panel of T. evansi and T. equiperdum reference strains. Coinertia analysis of the combined repeats and previously reported T. brucei brucei microsatellite genotypes revealed three distinct groups. Seven of the Venezuelan isolates grouped with globally distributed T. evansi strains, while TeAp-N/D1 and TeGu-N/D1 strains clustered in a separate group with the T. equiperdum STIB841/OVI strain isolated in South Africa. A third group included T. brucei brucei, two strains previously classified as T. evansi (GX and TC) and one as T. equiperdum (BoTat-1.1). Four maxicircle genes, Cytochrome b, Cythocrome Oxidase subunit 1, ATP synthase subunit 6 and NADH dehydrogenase subunit 8, were identified in the two Venezuelan strains clustering with the T. equiperdum STIB841/OVI strain. Phylogenetic analysis of the cox1 gene sequences further separated these two Venezuelan T. equiperdum strains: TeAp-N/D1 grouped with T. equiperdum strain STIB818 and T. brucei brucei, and TeGu-N/D1 with the T. equiperdum STIB841/OVI strain. CONCLUSION: Based on the Coinertia analysis and maxicircle gene sequence phylogeny, TeAp-N/D1 and TeGu-N/D1 constitute the first confirmed T. equiperdum strains described from Latin America.


Asunto(s)
ADN de Cinetoplasto , Genes Protozoarios , Variación Genética , Genotipo , Repeticiones de Microsatélite , Trypanosoma/clasificación , Trypanosoma/genética , Animales , Análisis por Conglomerados , ADN Protozoario/química , ADN Protozoario/genética , Equidae/parasitología , Caballos/parasitología , Datos de Secuencia Molecular , Filogenia , Roedores/parasitología , Análisis de Secuencia de ADN , Homología de Secuencia , Trypanosoma/aislamiento & purificación , Venezuela
3.
Vet Parasitol ; 161(3-4): 194-200, 2009 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-19286320

RESUMEN

Nine Trypanosoma sp. Venezuelan isolates, initially presumed to be T. evansi, were collected from three different hosts, capybara (Apure state), horse (Apure state) and donkey (Guarico state) and compared by the random amplification polymorphic DNA technique (RAPD). Thirty-one to 46 reproducible fragments were obtained with 12 of the 40 primers that were used. Most of the primers detected molecular profiles with few polymorphisms between the seven horse, capybara and donkey isolates. Quantitative analyses of the RAPD profiles of these isolates revealed a high degree of genetic conservation with similarity coefficients between 85.7% and 98.5%. Ten of the primers generated polymorphic RAPD profiles with two of the three Trypanosoma sp. horse isolates, namely TeAp-N/D1 and TeGu-N/D1. The similarity coefficient between these two isolates and the rest, ranged from 57.9% to 68.4% and the corresponding dendrogram clustered TeAp-N/D1 and Te Gu-N/D1 in a genetically distinct group.


Asunto(s)
ADN Protozoario/genética , Técnica del ADN Polimorfo Amplificado Aleatorio , Trypanosoma/genética , Trypanosoma/aislamiento & purificación , Animales , Secuencia de Bases , ADN Protozoario/clasificación , Variación Genética , Filogenia , Trypanosoma/clasificación , Venezuela
4.
Exp Parasitol ; 121(1): 1-7, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18848544

RESUMEN

Trypanosoma evansi is the causative agent of equine trypanosomosis, disease that affects horse's productivity and health. Parasitological and molecular methods are mostly used to detect the infection. The aim of this work was evaluate PCR sensitivity to detect T. evansi using the primers 21/22-mer, ITS1, ESAG 6/7 and TBR 1/2 designed from repetitive (multicopies) genomic sequences. The results were compare with two parasitological tests in mice, micro-haematocrite centrifugation technique and direct microscopic examination. The results shows (a) that the minimum amount of DNA from blood of highly parasitaemic mice that was detectable by PCR was 0.001 ng, using the ESAG6/7 and TBR1/2 primer, (b) using TBR1/2 primer for parasites purified could detect 0.000001 ng and (c) in the prepatent period PCR detect the presence of parasites earlier than parasitological techniques. Nevertheless, the percentage of detection for PCR varies depending on primer employed with 60% and 66% for ITS1 and 21/22-mer, and 80% for ESAG6/7 and TBR1/2. Consequently, TBR1/2 and ESAG6/7 were the best primers to monitor T. evansi infections in mice. For epidemiological application, such comparative evaluation should be made for detection of T. evansi in livestock such as horses.


Asunto(s)
Reacción en Cadena de la Polimerasa/veterinaria , Trypanosoma/aislamiento & purificación , Tripanosomiasis/veterinaria , Animales , Bovinos , Centrifugación , Cartilla de ADN/química , ADN Protozoario/análisis , ADN Protozoario/sangre , Modelos Animales de Enfermedad , Equidae , Femenino , Enfermedades de los Caballos/diagnóstico , Enfermedades de los Caballos/parasitología , Caballos , Ratones , Parasitemia/diagnóstico , Parasitemia/parasitología , Parasitemia/veterinaria , Reacción en Cadena de la Polimerasa/normas , Roedores , Sensibilidad y Especificidad , Trypanosoma/genética , Tripanosomiasis/diagnóstico , Tripanosomiasis/parasitología
5.
Exp Parasitol ; 111(2): 126-9, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16023641

RESUMEN

Trypanosoma vivax is the principal etiological agent of bovine trypanosomosis, a widely disseminated disease in tropical and subtropical regions. Here, we present a simple and reproducible method for the purification of T. vivax from experimentally infected and immunosuppressed sheep, using an isopycnic Percoll gradient, followed by DEAE-cellulose chromatography, with an estimated yield of 11-15%. This method could be used for the purification of T. vivax geographical isolates from various locations and from different natural hosts.


Asunto(s)
Parasitemia/veterinaria , Enfermedades de las Ovejas/parasitología , Trypanosoma vivax/aislamiento & purificación , Tripanosomiasis Africana/veterinaria , Animales , Centrifugación Isopicnica/veterinaria , Cromatografía DEAE-Celulosa/veterinaria , Terapia de Inmunosupresión , Parasitemia/inmunología , Parasitemia/parasitología , Proteínas Protozoarias/análisis , Ovinos , Enfermedades de las Ovejas/inmunología , Trypanosoma vivax/química , Tripanosomiasis Africana/inmunología , Tripanosomiasis Africana/parasitología
6.
J Parasitol ; 86(5): 1137-40, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11128495

RESUMEN

Schistosoma mansoni egg antigens are mostly responsible for the granulomatous pathology in human intestinal schistosomiasis. Several previous studies have indicated that the induction of an immune response against some parasite enzymes may protect against pathology. The present work was designed to identify enzyme activities present in a standard soluble egg antigen (SEA) preparation. Simple colorimetric analyses were performed incubating SEA with 2-naphthyl, 2-naphthylamide (2NA), or p-nitrophenyl substrates at different pHs in the absence of added effectors. Results showed prominent acid phosphatase (pH 5.4), alkaline phosphatase (pH 8.5), and N-acetyl-beta-glucosaminidase (pH 5.4) activities. Relevant peptidase activities were also detected at pH 6.5-7.5 against 2NA derivatives of (1) aliphatic (alpha-Ala > beta-Ala > Leu > Met > S-benzyl-Cys), polar (Ser > Gln), basic (Arg > Lys > ornithine), and acidic (Glu) amino acids; (2) dipeptides: X-Ala (X = Gly > Leu > Lys > Asp), X-Arg (X = Ala > Arg > Phe > Gly > Pro > Asp), Ser-Met, and Phe-Pro; and (3) tripeptides (Ala-Phe-Pro > Phe-Pro-Ala). The data demonstrated that S. mansoni SEA contains a rich set of hydrolases with different specificities that might play a role in the egg physiology and possibly also in the host-parasite relationships.


Asunto(s)
Antígenos Helmínticos/metabolismo , Hidrolasas/metabolismo , Schistosoma mansoni/enzimología , Animales , Cricetinae , Óvulo/inmunología , Schistosoma mansoni/crecimiento & desarrollo , Schistosoma mansoni/inmunología , Esquistosomiasis mansoni/parasitología
7.
Am J Med ; 76(6): 1118-23, 1984 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6328993

RESUMEN

A well-documented case of cytomegalovirus- and Cryptosporidium-associated cholecystitis is described in a 19-year-old heterosexual Haitian man who had the acquired immune deficiency syndrome and acute acalculous gangrenous cholecystitis associated with these pathogens. This case adds to the spectrum of the manifestations of the profoundly immunocompromised state.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Colecistitis/etiología , Coccidiosis/etiología , Infecciones por Citomegalovirus/etiología , Gastroenteritis/etiología , Adulto , Colecistitis/microbiología , Colecistitis/parasitología , Colecistitis/patología , Coccidios/crecimiento & desarrollo , Coccidiosis/patología , Citomegalovirus/crecimiento & desarrollo , Infecciones por Citomegalovirus/patología , Vesícula Biliar/microbiología , Vesícula Biliar/patología , Gangrena , Gastroenteritis/microbiología , Gastroenteritis/parasitología , Haití/etnología , Humanos , Masculino , Estómago/parasitología , Estómago/patología , Estados Unidos
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