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1.
Int J Parasitol ; 41(13-14): 1385-96, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22051399

RESUMEN

Species of the subgenus Trypanosoma (Megatrypanum) have been reported in cattle and other domestic and wild ruminants worldwide. A previous study in Brazil found at least four genotypes infecting cattle (Bos taurus), but only one in water buffalo (Bubalus bubalis). However, the small number of isolates examined from buffalo, all inhabiting nearby areas, has precluded evaluation of their diversity, host associations and geographical structure. To address these questions, we evaluated the genetic diversity and phylogeographical patterns of 25 isolates from water buffalo and 28 from cattle from four separate locations in Brazil and Venezuela. Multigene phylogenetic analyses of ssrRNA, internal transcribed spacer of rDNA (ITSrDNA), 5SrRNA, glycosomal glyceraldehyde 3-phosphate dehydrogenase (gGAPDH), mitochondrial cytochrome b (Cyt b), spliced leader (SL) and cathepsin L-like (CATL) sequences positioned all isolates from sympatric and allopatric buffalo populations into the highly homogeneous genotype TthIA, while the cattle isolates were assigned to three different genotypes, all distinct from TthIA. Polymorphisms in all of these sequences separated the trypanosomes infecting water buffalo, cattle, sheep, antelope and deer, and suggested that they correspond to separate species. Congruent phylogenies inferred with all genes indicated a predominant clonal structure of the genotypes. The multilocus analysis revealed one monophyletic assemblage formed exclusively by trypanosomes of ruminants, which corresponds to the subgenus T. (Megatrypanum). The high degree of host specificity, evidenced by genotypes exclusive to each ruminant species and lack of genotype shared by different host species, suggested that the evolutionary history of trypanosomes of this subgenus was strongly constrained by their ruminant hosts. However, incongruence between ruminant and trypanosome phylogenies did not support host-parasite co-evolution, indicating that host switches have occurred across ruminants followed by divergences, giving rise to new trypanosome genotypes adapted exclusively to one host species.


Asunto(s)
Evolución Biológica , Búfalos/parasitología , Enfermedades de los Bovinos/parasitología , Filogenia , Rumiantes/parasitología , Trypanosoma/clasificación , Trypanosoma/genética , Tripanosomiasis/veterinaria , Animales , Brasil , Bovinos , Genotipo , Especificidad del Huésped , Datos de Secuencia Molecular , Filogeografía , Trypanosoma/aislamiento & purificación , Trypanosoma/fisiología , Tripanosomiasis/parasitología , Venezuela
2.
Protist ; 162(3): 503-24, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21420905

RESUMEN

We comparatively examined the nutritional, molecular and optical and electron microscopical characteristics of reference species and new isolates of trypanosomatids harboring bacterial endosymbionts. Sequencing of the V7V8 region of the small subunit of the ribosomal RNA (SSU rRNA) gene distinguished six major genotypes among the 13 isolates examined. The entire sequences of the SSU rRNA and glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH) genes were obtained for phylogenetic analyses. In the resulting phylogenetic trees, the symbiont-harboring species clustered as a major clade comprising two subclades that corresponded to the proposed genera Angomonas and Strigomonas. The genus Angomonas comprised 10 flagellates including former Crithidia deanei and C. desouzai plus a new species. The genus Strigomonas included former Crithidia oncopelti and Blastocrithidia culicis plus a new species. Sequences from the internal transcribed spacer of ribosomal DNA (ITS rDNA) and size polymorphism of kinetoplast DNA (kDNA) minicircles revealed considerable genetic heterogeneity within the genera Angomonas and Strigomonas. Phylogenetic analyses based on 16S rDNA and ITS rDNA sequences demonstrated that all of the endosymbionts belonged to the Betaproteobacteria and revealed three new species. The congruence of the phylogenetic trees of trypanosomatids and their symbionts support a co-divergent host-symbiont evolutionary history.


Asunto(s)
Betaproteobacteria/clasificación , Betaproteobacteria/genética , Simbiosis , Trypanosomatina/clasificación , Trypanosomatina/genética , Secuencia de Bases , Betaproteobacteria/aislamiento & purificación , Betaproteobacteria/ultraestructura , Evolución Biológica , Código de Barras del ADN Taxonómico/métodos , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Intergénico/química , ADN Intergénico/genética , ADN de Cinetoplasto/química , ADN de Cinetoplasto/genética , ADN Protozoario/química , ADN Protozoario/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Funciones de Verosimilitud , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Filogenia , Polimorfismo Genético , ARN Ribosómico 16S/genética , Subunidades Ribosómicas Pequeñas/genética , Análisis de Secuencia de ADN , Simbiosis/genética , Trypanosomatina/aislamiento & purificación , Trypanosomatina/ultraestructura
3.
Int J Parasitol ; 40(3): 345-55, 2010 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-19766649

RESUMEN

The genetic diversity and phylogeographical patterns of Trypanosoma species that infect Brazilian bats were evaluated by examining 1043 bats from 63 species of seven families captured in Amazonia, the Pantanal, Cerrado and the Atlantic Forest biomes of Brazil. The prevalence of trypanosome-infected bats, as estimated by haemoculture, was 12.9%, resulting in 77 cultures of isolates, most morphologically identified as Trypanosoma cf. cruzi, classified by barcoding using partial sequences from ssrRNA gene into the subgenus Schizotrypanum and identified as T. cruzi (15), T. cruzi marinkellei (37) or T. cf. dionisii (25). Phylogenetic analyses using nuclear ssrRNA, glycosomal glyceraldehyde 3-phosphate dehydrogenase (gGAPDH) and mitochondrial cytochrome b (Cyt b) gene sequences generated three clades, which clustered together forming the subgenus Schizotrypanum. In addition to vector association, bat trypanosomes were related by the evolutionary history, ecology and phylogeography of the bats. Trypanosoma cf. dionisii trypanosomes (32.4%) infected 12 species from four bat families captured in all biomes, from North to South Brazil, and clustered with T. dionisii from Europe despite being separated by some genetic distance. Trypanosoma cruzi marinkellei (49.3%) was restricted to phyllostomid bats from Amazonia to the Pantanal (North to Central). Trypanosoma cruzi (18.2%) was found mainly in vespertilionid and phyllostomid bats from the Pantanal/Cerrado and the Atlantic Forest (Central to Southeast), with a few isolates from Amazonia.


Asunto(s)
Quirópteros/parasitología , Variación Genética , Trypanosoma/clasificación , Trypanosoma/aislamiento & purificación , Tripanosomiasis/veterinaria , Animales , Brasil , Análisis por Conglomerados , Citocromos b/genética , ADN Protozoario/química , ADN Protozoario/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Genes de ARNr , Geografía , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Datos de Secuencia Molecular , Filogenia , Proteínas Protozoarias/genética , ARN Protozoario/genética , ARN Ribosómico 18S/genética , Análisis de Secuencia de ADN , Trypanosoma/genética , Tripanosomiasis/parasitología
4.
Vet. parasitol ; 160(1/2): 18-24, 2009. tab
Artículo en Inglés | Sec. Munic. Saúde SP, COVISA-Acervo | ID: sms-1338

RESUMEN

To identify natural infections by Leishmania spp. in insect vectors of cutaneous and visceral leishmaniasis, we performed field studies in natural and anthropic environments in the Guaicurus Settlement (Bodoquena Range) of the Bonito municipality, Mato Grosso do Sul state, Brazil. From October 2002 to October 2003, a total of 1395 sandfly females were captured with Shannon and light traps and dissected in search of flagellates. The sample is composed of a total of 13 species, with Lutzomyia almerioi (59.9%) and Lutzomyia longipalpis (31.4%) predominant. Infections by flagellates were directly observed in three of the dissected of Lu. almerioi females (0.36%). To increase the sensitivity of detection, DNA extracted from pools of the 1220 dissected females (Lu. almerioi 808, Lu. longipalpis 399 and Nyssomyia whitmani 13) was subjected to small subunit rRNA-based polymerase chain reactions (SSU-PCR). DNA from Leishmania (L.) infantum chagasi was detected in at least 0.37% of Lu. almerioi females and in 0.25% of Lu. longipalpis females. The DNA of the Leishmania (Viannia) sp. was detected in 0.12% of Lu. almerioi and in 0.70% of Lu. longipalpis. Leishmania (L.) amazonensis was found in 1.25% of Lu. longipalpis. Mixed infections of L. (Leishmania) sp. and L. (Viannia) sp. were found in 0.50% of Lu. longipalpis. When considering that each positive pool contained at least a single infected specimen, we found a 1.23% rate of Leishmania spp. infection among the total population of dissected female sand flies as determined by PCR. This is the first report of natural infection by L. (L.) infantum chagasi and L. (Viannia) sp. in Lu. almerioi. It is also the first report of infection by L. (Viannia) sp. in Lu. longipalpis. The observation that Lu. longipalpis and Lu. almerioi are naturally infected by agents of both cutaneous and visceral leishmaniases suggests that these two species play a role in the transmission of these diseases within the study area. Furthermore, the finding that Lu. longipalpis has been naturally infected by L. (L.) amazonensis and L. (Viannia) sp., and Lu. almerioi by L. (L.) infantum chagasi and L. (Viannia), suggests their participation as permissive vectors


Asunto(s)
Animales , Leishmania , Leishmaniasis Visceral , Leishmaniasis Cutánea , Infecciones , Insectos Vectores
5.
Mem Inst Oswaldo Cruz ; 101(2): 175-93, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16830711

RESUMEN

Investigation was undertaken on the behaviour of the phlebotomine fauna in caves, forests, and anthropic environments of the Serra da Bodoquena, between January 1998 and January 2000. This paper reports on the phlebotomines captured in forested areas with automatic light traps (ALT), Shannon traps (ST), aspiration (AN), at natural resting sites and by human attractiveness (HA) during 24 h. The diversity and abundance of the species were investigated with ALT installed at 16 points (ground level) and 6 in the canopy. Natural infection by flagellates was investigated in females captured with ST AN, and HA. The sandfly fauna was represented by 23 species. Twenty-two of these were captured with ALT 15 of them on the western side, and 20 on the eastern. Lutzomyia longipalpis and Nyssomyia whitmani were the most abundant on the former and this species together with Lutzomyia almerioi on the latter side. On the eastern side the ecotopes located close to caves rendered a significantly greater number (P < or = 0.01) of specimens than did more distant sites. On this side Lu. almerioi contributed with 56% of the total number of specimens. Lu. almerioi females were predominantly attracted by humans (96.4%) and by ST (93.2%) and three of the 2173 dissected (0.138%) presented natural infection by flagellates. The attraction of Lu. almerioi to humans occurred during all seasons, predominantly in the summer, and in nocturnal and diurnal periods. Thus it is bothersome to inhabitants of and visitors to the Bodoquena ridge and a potential vector of flagellates.


Asunto(s)
Insectos Vectores/fisiología , Psychodidae/fisiología , Animales , Brasil , Femenino , Humanos , Insectos Vectores/clasificación , Leishmaniasis/transmisión , Masculino , Densidad de Población , Psychodidae/clasificación , Estaciones del Año , Árboles
6.
Mem. Inst. Oswaldo Cruz ; 101(2): 175-193, Mar. 2006. mapas, graf
Artículo en Inglés | LILACS | ID: lil-430895

RESUMEN

Investigation was undertaken on the behaviour of the phlebotomine fauna in caves, forests, and anthropic environments of the Serra da Bodoquena, between January 1998 and January 2000. This paper reports on the phlebotomines captured in forested areas with automatic light traps (ALT), Shannon traps (ST), aspiration (AN), at natural resting sites and by human attractiveness (HA) during 24 h. The diversity and abundance of the species were investigated with ALT installed at 16 points (ground level) and 6 in the canopy. Natural infection by flagellates was investigated in females captured with ST, AN, and HA. The sand fly fauna was represented by 23 species. Twenty-two of these were captured with ALT, 15 of them on the western side, and 20 on the eastern. Lutzomyia longipalpis and Nyssomyia whitmani were the most abundant on the former and this species together with Lutzomyia almerioi on the latter side. On the eastern side the ecotopes located close to caves rendered a significantly greater number (P < 0.01) of specimens than did more distant sites. On this side Lu. almerioi contributed with 56 percent of the total number of specimens. Lu. almerioi females were predominantly attracted by humans (96.4 percent) and by ST (93.2 percent) and three of the 2173 dissected (0.138 percent) presented natural infection by flagellates. The attraction of Lu. almerioi to humans occurred during all seasons, predominantly in the summer, and in nocturnal and diurnal periods. Thus it is bothersome to inhabitants of and visitors to the Bodoquena ridge and a potential vector of flagellates.


Asunto(s)
Humanos , Animales , Masculino , Femenino , Insectos Vectores/fisiología , Psychodidae/fisiología , Brasil , Insectos Vectores/clasificación , Leishmaniasis/transmisión , Densidad de Población , Psychodidae/clasificación , Estaciones del Año , Árboles
7.
Rev. bras. entomol ; 47(2): 283-296, 2003. mapas, tab, graf
Artículo en Inglés | LILACS | ID: lil-352847

RESUMEN

The present paper deals with the phlebotomine species captured during the period from January 1998 to June 2000 in 12 caves located in the Serra da Bodoquena, situated in the south central region of Mato Grosso do Sul State, Brazil. Three of the caves are situated further north (in Bodoquena county), seven in the central area (Bonito county) and two in the south (Jardim county). These last two caves and three of those in Bonito are located at the west side of the ridge. Eighteen species of phlebotomines were captured within the caves: Brumptomyia avellari (Costa Lima, 1932), Brumptomyia brumpti (Larrousse, 1920), Brumptomyia cunhai (Mangabeira, 1942), Brumptomyia galindoi (Fairchild & Hertig, 1947), Evandromyia corumbaensis (Galati, Nunes, Oshiro & Rego, 1989), Lutzomyia almerioi Galati & Nunes, 1999, Lutzomyia longipalpis (Lutz & Neiva, 1912), Martinsmyia oliveirai (Martins, Falcão & Silva, 1970), Micropygomyia acanthopharynx (Martins, Falcão & Silva, 1962), Micropygomyia peresi (Mangabeira, 1942), Micropygomyia quinquefer (Dyar, 1929), Nyssomyia whitmani (Antunes & Coutinho, 1939), Psathyromyia campograndensis (Oliveira, Andrade-Filho, Falcão & Brazil, 2001), Psathyromyia punctigeniculata (Floch & Abonnenc, 1944), Psathyromyia shannoni (Dyar, 1929), Pintomyia kuscheli (Le Pont, Martinez, Torrez-Espejo & Dujardin, 1998), Sciopemyia sordellii (Shannon & Del Ponte, 1927) and Sciopemyia sp. A total of 29,599 phlebotomine sandflies was obtained. Lutzomyia almerioi was absolutely predominant (91.5 per cent) over the other species on both sides of the Bodoquena ridge, with the exception of the southern caves in which it was absent. It presents summer predominance, with nocturnal and diurnal activities. The species breeds in the caves and was captured during daytime both in the dark area and in the mouth of the caves. Martinsmyia oliveirai, the second most frequent sandfly, also presents a summer peak and only predominated over the other species in one cave, in which there were human residues.


Asunto(s)
Animales , Dípteros , Ecología , Psychodidae
8.
Rev. saúde pública ; 31(4): 378-90, ago. 1997. tab
Artículo en Portugués | LILACS | ID: lil-199526

RESUMEN

Nas Américas, Lutzomyia longipalpis tem sido incriminada como vetora da leishmaniose visceral em, praticamente, todas as áreas de ocorrência dessa parasitose. A notificaçäo de casos humanos a partir de 1980 e a presença de cäes com aspecto sugestivo de leishmaniose visceral no Município de Corumbá, Estado de Mato Grosso do Sul, Brasil, levaram a investigaçöes entomológicas na área, com o objetivo de identificar a populaçäo de flebotomíneo vetora. A pesquisa foi realizada no peri e intradomicílio de três residências urbanas e em ecótopo natural, representado por uma gruta, situado fora doperímetro urbano. As capturas, semanais em sua maioria, foram realizadas com armadilhas automáticas luminosas, no período de 1984 a 1986. Os dados metereológicos desse período foram obtidos junto à Estaçäo Metereológica da cidade e os de 1925 a 1982, de bibliografia. A fauna flebotomínea urbana, composta de oito espécies, mostrou-se semelhante à da gruta, porém nesta, a abundância das espécies foi maior. Na área urbana, Lu. cruzi predominou tanto no intra como no peridomicílio: no bairro central, representou 90,3 por cento dos espécimes e nos dois bairros periféricos, os seus percentuais foram menores. Lu. forattinii, também, teve freqüência expressiva em um dos bairros periféricos (39,0 por cento). Na gruta, Lu. corumbaensis foi a espécie predominante. Comenta-se o impacto das condiçöes climáticas e do inseticida aplicado na área urbana na freqüência das espécies, e da utilizaçäo da gruta como criadouro pelos flebotomíneos, com base na evoluçäo da razäo entre os sexos ao longo do período. Foram adicionadas informaçöes sobre antropofilia e de coleta com isca canina de Lu. forattinii. O predomínio de Lu. cruzi na área urbana; a expressiva freqüência de Lu. forattinii na periferia da cidade, bem como a sua antropofilia e o estreito grau de parentesco destas espécies com Lu. longipalpis, a principal vetora da leishmaniose visceral em outras áreas da América, säo aspectos que sugerem a participaçÝo de ambas na transmissäo da doença, em Corumbá.


Asunto(s)
Psychodidae , Vectores de Enfermedades , Efectos del Clima , Leishmaniasis Visceral/transmisión , Densidad de Población
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