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1.
Epidemiol Serv Saude ; 27(3): e2017343, 2018 10 22.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-30365698

RESUMEN

OBJECTIVE: to describe the geographical distribution of intermediate hosts of Schistosoma mansoni in five Brazilian states. METHODS: this was a descriptive cross-sectional study; municipalities were selected in the states of Paraná (78), Minas Gerais (120), Bahia (82), Pernambuco (51) , and Rio Grande do Norte (98), for the period 2012 to 2014; these municipalities were chosen because they did not have current records of the presence of snails vectores de S. mansoni. The molluscs were captured and taxonomically identified and examined for S. mansoni cercariae. RESULTS: the work was carried out in 427 municipalities (99.5% of the 429 selected); the presence of mollusks was registered in 300 (70.2%) municipalities; Biomphalaria glabrata were found in 62 (21%) municipalities, B. straminea in 181 (60%), B. tenagophila in three (1%); B. glabrata/B. straminea association was found in 53 municipalities (18%) and B. glabrata/B. tenagophila association in one (0.3%) municipality. CONCLUSION: B. glabrata, B. straminea and B. tenagophila distribution records obtained in this study are consistent with previously known distribution.


Asunto(s)
Biomphalaria/parasitología , Vectores de Enfermedades/clasificación , Schistosoma mansoni/aislamiento & purificación , Esquistosomiasis mansoni/transmisión , Animales , Biomphalaria/clasificación , Brasil , Estudios Transversales , Especificidad de la Especie
2.
Epidemiol. serv. saúde ; 27(3): e2017343, 2018. tab, graf
Artículo en Portugués | LILACS | ID: biblio-975180

RESUMEN

Objetivo: descrever a distribuição geográfica dos hospedeiros intermediários do Schistosoma mansoni em cinco estados brasileiros. Métodos: estudo transversal; foram selecionados municípios dos estados do Paraná (78), Minas Gerais (120), Bahia (82), Pernambuco (51) e Rio Grande do Norte (98), nos anos de 2012 a 2014; esses municípios foram escolhidos por não possuírem registros atualizados da presença de caramujos hospedeiros intermediários de S. mansoni; moluscos foram capturados, taxonomicamente identificados e examinados para verificação de cercárias de S. mansoni. Resultados: os trabalhos foram realizados em 427 municípios (99,5% dos 429 selecionados); foi registrada presença de moluscos em 300 (70,2%) municípios e a ocorrência de Biomphalaria glabrata em 62 (21%) municípios, B. straminea em 181 (60%), B. tenagophila em três (1%); associação de B. glabrata/B. straminea foi encontrada em 53 (18%), e de B. glabrata/B. tenagophila em um (0,3%). Conclusão: os registros de B. glabrata, B. straminea e B. tenagophila estão de acordo com a distribuição conhecida.


Objetivo: describir la distribución geográfica de los hospedadores intermediarios de Schistosoma mansoni en cinco estados brasileños. Métodos: estudio epidemiológico transversal; el estudio fue realizado en municipios de los estados de Paraná (78), Minas Gerais (120), Bahia (82), Pernambuco (51) y Rio Grande do Norte (98), entre 2012 y 2014; estos municipios fueron elegidos por no poseer registros actualizados de la presencia de caracoles vectores de S. mansoni; los moluscos fueron capturados, taxonómicamente identificados y examinados para la verificación de cercarias de S. mansoni. Resultados: los trabajos fueron realizados en 427 municipios (99,5% de 429 municipios seleccionados); fue registrada presencia de moluscos en 300 (70,2%) municípios; la presencia de Biomphalaria glabrata fue registrada en 62 (21%) municipios, B. straminea en 181 (60%) y B. tenagophila en três (1%); se observó asociación de B. glabrata con B. straminea en 53 (18%) y de B. glabrata con B. tenagophila en uno (0,3%). Conclusión: los registros de Biomphalaria están de acuerdo con la distribución conocida.


Objective: to describe the geographical distribution of intermediate hosts of Schistosoma mansoni in five Brazilian states. Methods: this was a descriptive cross-sectional study; municipalities were selected in the states of Paraná (78), Minas Gerais (120), Bahia (82), Pernambuco (51) , and Rio Grande do Norte (98), for the period 2012 to 2014; these municipalities were chosen because they did not have current records of the presence of snails vectores de S. mansoni. The molluscs were captured and taxonomically identified and examined for S. mansoni cercariae. Results: the work was carried out in 427 municipalities (99.5% of the 429 selected); the presence of mollusks was registered in 300 (70.2%) municipalities; Biomphalaria glabrata were found in 62 (21%) municipalities, B. straminea in 181 (60%), B. tenagophila in three (1%); B. glabrata/B. straminea association was found in 53 municipalities (18%) and B. glabrata/B. tenagophila association in one (0.3%) municipality. Conclusion: B. glabrata, B. straminea and B. tenagophila distribution records obtained in this study are consistent with previously known distribution.


Asunto(s)
Humanos , Masculino , Femenino , Schistosoma mansoni , Esquistosomiasis , Biomphalaria , Vectores de Enfermedades , Estudios Transversales , Estudios Ecológicos , Mapeo Geográfico
3.
Parasitol Res ; 114(8): 2835-43, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25924794

RESUMEN

The ubiquitination and deubiquitination of proteins can alter diverse cellular processes, such as proteolysis, trafficking, subcellular localisation, DNA repair, apoptosis and signal transduction. Deubiquitinating enzymes (DUBs) are responsible for removing ubiquitin from their target proteins. Previous reports have shown the presence of two subfamilies of DUBs in Schistosoma mansoni: Ub carboxyl-terminal hydrolase (UCH) and Ub-specific protease (USP). In this study, we analysed the ovarian tumour (OTU) and Machado-Joseph disease protein domain (MJD) proteases found in the Schistosoma mansoni genome database. An in silico analysis identified two different MJD subfamily members, SmAtaxin-3 and SmJosephin, and five distinct OTU proteases, SmOTU1, SmOTU3, SmOTU5a, SmOTU6b and SmOtubain. The phylogenetic analysis showed the evolutionary conservation of these proteins. Furthermore, the 3D structures confirmed the similarity of these proteins with human proteins. In addition, we performed quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and observed distinct expression profiles for all of the investigated transcripts between the cercariae, schistosomula and adult worm stages. Taken together, our data suggest that MJD and OTU subfamily members contribute to regulating the activity of the Ub-proteasome system during the life cycle of this parasite.


Asunto(s)
Endopeptidasas/metabolismo , Regulación Enzimológica de la Expresión Génica , Complejo de la Endopetidasa Proteasomal/metabolismo , Procesamiento Proteico-Postraduccional , Schistosoma mansoni/enzimología , Animales , Cercarias , Femenino , Proteínas del Helminto/metabolismo , Humanos , Estadios del Ciclo de Vida , Filogenia , Schistosoma mansoni/genética , Schistosoma mansoni/crecimiento & desarrollo , Ubiquitinación
4.
Mem. Inst. Oswaldo Cruz ; 109(1): 1-8, 02/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-703649

RESUMEN

Several genes related to the ubiquitin (Ub)-proteasome pathway, including those coding for proteasome subunits and conjugation enzymes, are differentially expressed during the Schistosoma mansoni life cycle. Although deubiquitinating enzymes have been reported to be negative regulators of protein ubiquitination and shown to play an important role in Ub-dependent processes, little is known about their role in S. mansoni . In this study, we analysed the Ub carboxyl-terminal hydrolase (UCHs) proteins found in the database of the parasite’s genome. An in silico ana- lysis (GeneDB and MEROPS) identified three different UCH family members in the genome, Sm UCH-L3, Sm UCH-L5 and Sm BAP-1 and a phylogenetic analysis confirmed the evolutionary conservation of the proteins. We performed quantitative reverse transcription-polymerase chain reaction and observed a differential expression profile for all of the investigated transcripts between the cercariae and adult worm stages. These results were corroborated by low rates of Z-Arg-Leu-Arg-Gly-Gly-AMC hydrolysis in a crude extract obtained from cercariae in parallel with high Ub conjugate levels in the same extracts. We suggest that the accumulation of ubiquitinated proteins in the cercaria and early schistosomulum stages is related to a decrease in 26S proteasome activity. Taken together, our data suggest that UCH family members contribute to regulating the activity of the Ub-proteasome system during the life cycle of this parasite.


Asunto(s)
Animales , Endopeptidasas/genética , Schistosoma mansoni/enzimología , Ubiquitina Tiolesterasa/genética , Cercarias/enzimología , Cercarias/genética , Secuencia Conservada/genética , Evolución Molecular , Expresión Génica , Genoma de los Helmintos/genética , Genoma/genética , Estadios del Ciclo de Vida/genética , Ratones Endogámicos BALB C , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Alineación de Secuencia , Schistosoma mansoni/genética , Schistosoma mansoni/crecimiento & desarrollo , Transcriptoma/fisiología , Transcitosis/fisiología , Ubiquitina Tiolesterasa/clasificación , Proteasas Ubiquitina-Específicas/genética , Ubiquitinación/fisiología
5.
Mem Inst Oswaldo Cruz ; 109(1): 1-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24271000

RESUMEN

Several genes related to the ubiquitin (Ub)-proteasome pathway, including those coding for proteasome subunits and conjugation enzymes, are differentially expressed during the Schistosoma mansoni life cycle. Although deubiquitinating enzymes have been reported to be negative regulators of protein ubiquitination and shown to play an important role in Ub-dependent processes, little is known about their role in S. mansoni . In this study, we analysed the Ub carboxyl-terminal hydrolase (UCHs) proteins found in the database of the parasite's genome. An in silico ana- lysis (GeneDB and MEROPS) identified three different UCH family members in the genome, Sm UCH-L3, Sm UCH-L5 and Sm BAP-1 and a phylogenetic analysis confirmed the evolutionary conservation of the proteins. We performed quantitative reverse transcription-polymerase chain reaction and observed a differential expression profile for all of the investigated transcripts between the cercariae and adult worm stages. These results were corroborated by low rates of Z-Arg-Leu-Arg-Gly-Gly-AMC hydrolysis in a crude extract obtained from cercariae in parallel with high Ub conjugate levels in the same extracts. We suggest that the accumulation of ubiquitinated proteins in the cercaria and early schistosomulum stages is related to a decrease in 26S proteasome activity. Taken together, our data suggest that UCH family members contribute to regulating the activity of the Ub-proteasome system during the life cycle of this parasite.


Asunto(s)
Endopeptidasas/genética , Schistosoma mansoni/enzimología , Ubiquitina Tiolesterasa/genética , Animales , Cercarias/enzimología , Cercarias/genética , Secuencia Conservada/genética , Evolución Molecular , Expresión Génica , Genoma/genética , Genoma de los Helmintos/genética , Estadios del Ciclo de Vida/genética , Ratones Endogámicos BALB C , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Schistosoma mansoni/genética , Schistosoma mansoni/crecimiento & desarrollo , Alineación de Secuencia , Transcriptoma/fisiología , Transcitosis/fisiología , Ubiquitina Tiolesterasa/clasificación , Proteasas Ubiquitina-Específicas/genética , Ubiquitinación/fisiología
6.
Mem Inst Oswaldo Cruz ; 107(6): 740-6, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22990962

RESUMEN

Angiostrongylus cantonensis is the most common aetiological agent of human eosinophilic meningoencephalitis. Following a report indicating the presence of this parasite in Brazil in 2007, the present study was undertaken to investigate the presence of A. cantonensis in the surrounding Brazilian port areas. In total, 30 ports were investigated and the following molluscs were identified: Achatina fulica, Belocaulus sp., Bradybaena similaris sp., Cyclodontina sp., Helix sp., Leptinaria sp., Melampus sp., Melanoides tuberculata, Phyllocaulis sp., Pomacea sp., Pseudoxychona sp., Rhinus sp., Sarasinula marginata, Streptaxis sp., Subulina octona, Succinea sp., Tomigerus sp., Wayampia sp. and specimens belonging to Limacidae and Orthalicinae. Digestion and sedimentation processes were performed and the sediments were examined. DNA was extracted from the obtained larvae and the internal transcribed spacer region 2 was analysed by polymerase chain reaction-restriction fragment length polymorphism after digestion with the endonuclease ClaI. Of the 30 ports investigated in this study, 11 contained molluscs infected with A. cantonensis larvae. The set of infected species consisted of S. octona, S. marginata, A. fulica and B. similaris. A total of 36.6% of the investigated ports were positive for A. cantonensis, indicating a wide distribution of this worm. It remains uncertain when and how A. cantonensis was introduced into South America.


Asunto(s)
Angiostrongylus cantonensis/aislamiento & purificación , Vectores de Enfermedades , Moluscos/parasitología , Animales , Brasil , Moluscos/clasificación , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción
7.
Mem. Inst. Oswaldo Cruz ; 107(6): 740-746, set. 2012. ilus, mapas, tab
Artículo en Inglés | LILACS | ID: lil-649488

RESUMEN

Angiostrongylus cantonensis is the most common aetiological agent of human eosinophilic meningoencephalitis. Following a report indicating the presence of this parasite in Brazil in 2007, the present study was undertaken to investigate the presence of A. cantonensis in the surrounding Brazilian port areas. In total, 30 ports were investigated and the following molluscs were identified: Achatina fulica, Belocaulus sp., Bradybaena similaris sp., Cyclodontina sp., Helix sp., Leptinaria sp., Melampus sp., Melanoides tuberculata, Phyllocaulis sp., Pomacea sp., Pseudoxychona sp., Rhinus sp., Sarasinula marginata, Streptaxis sp., Subulina octona, Succinea sp., Tomigerus sp., Wayampia sp. and specimens belonging to Limacidae and Orthalicinae. Digestion and sedimentation processes were performed and the sediments were examined. DNA was extracted from the obtained larvae and the internal transcribed spacer region 2 was analysed by polymerase chain reaction-restriction fragment length polymorphism after digestion with the endonuclease ClaI. Of the 30 ports investigated in this study, 11 contained molluscs infected with A. cantonensis larvae. The set of infected species consisted of S. octona, S. marginata, A. fulica and B. similaris. A total of 36.6% of the investigated ports were positive for A. cantonensis, indicating a wide distribution of this worm. It remains uncertain when and how A. cantonensis was introduced into South America.


Asunto(s)
Animales , Angiostrongylus cantonensis/aislamiento & purificación , Vectores de Enfermedades , Moluscos/parasitología , Brasil , Moluscos/clasificación , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción
9.
Belo Horizonte; s.n; 26 abr. 2007. xii,116 p. ilus, mapas, tab.
Tesis en Portugués | LILACS | ID: lil-457776

RESUMEN

Com o advento da técnica de seqüenciamento automático de nucleotídeos tornou-se possível, em um curto intervalo de tempo, um aumento considerável de informações sobre o genoma de diversos organismos. Oseqüenciamento de DNA mitocondrial de moluscos vem aumentando consideravelmente nos últimos anos. Do gênero Biomphalaria, somente uma espécie (B. glabrata) tinha o seu genoma mitocondrial totalmente seqüenciado. Neste trabalho foi seqüenciado e caracterizado o DNAmt de Biomphalaria tenagophila, molusco hospedeiro intermediário do Schistosoma mansoni no Brasil. Esta espécie possui linhagens suscetíveis à infecção pelo S. mansoni, bem como cepa totalmente resistente, como é o caso da linhagem geográfica da Reserva Biológica do Taim (RS), foco do presente estudo. O tamanho do genoma encontrado foi de 13.722 pb:13 RNAs mensageiros (RNAm), 22 RNAs de transferência (RNAt) e 2 RNAs ribossomais (RNAr). Além do seqüenciamento, foi analisada a organização do genoma de B. tenagophila pelo conteúdo e localização das regiões codificantes e não codificantes, regiões de sobreposições de genes. Foi realizada a comparação das seqüências dos aminoácidos; dos códons de iniciação e de parada das seqüências nucleotídicas dos RNAt, dos RNAr12S e dos RNAr16S e da organização dos genes entre B. tenagophila e B. glabrata, hospedeira intermediária mais importante do Brasil. Além disso, foram desenhadas as estruturas secundárias de 6 RNAt, de B. tenagophila; e estimada a relação filogenética entre moluscos que tinham seu genoma mitocondrial completo depositado no GenBank, utilizando os métodos de agrupamento de vizinho, da máxima parcimônia e da máxima verossimilhança. Foram encontradas diferenças no tamanho e na composição dos genes entre B. tenagophila e B. glabrata. A ordem gênica mitocondrial de B. tenagophila foi a mesma de B. glabrata. A seqüência completa do genoma mitocondrial de B. tenagophila foi depositada no banco de dados GenBank com o número de acesso EF433576.


Asunto(s)
Biomphalaria , ADN Mitocondrial , Moluscos , Brasil
12.
Mem. Inst. Oswaldo Cruz ; 101(supl.1): 179-184, Oct. 2006. mapas, tab
Artículo en Inglés | LILACS | ID: lil-441244

RESUMEN

This study focuses on the geographic distribution of the snail of the genus Biomphalaria and evaluates its infectivity by Schistosoma mansoni in 5264 specimens collected in the municipality of Juiz de Fora, Minas Gerais, Brazil. Of the 31 locations studied, 6 were reservoirs, 11 rudimentary holding ponds, 7 irrigation ditches, 5 lakes, 1 ornamental pond, and 1 waterfall. Intermediate hosts were found only in the rudimentary ponds and ditches, which were 100 percent positive. Using morphological and molecular analysis techniques, B. tenagophila, B. peregrina, and B. straminea were identified. This is the first report of B. stramínea in the municipality, and evaluation of its infective potential revealed susceptibility of 25.4 percent. Although we did not find specimens of Biomphalaria infected by S. mansoni, the data obtained indicate the presence of intermediate hosts, especially in the irrigation ditches in Juiz de Fora, and their proximity to contaminated areas.


Asunto(s)
Animales , Biomphalaria/clasificación , Vectores de Enfermedades/clasificación , Schistosoma mansoni , Brasil , Biomphalaria/parasitología , Densidad de Población
13.
Mem Inst Oswaldo Cruz ; 101 Suppl 1: 179-84, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17308767

RESUMEN

This study focuses on the geographic distribution of the snail of the genus Biomphalaria and evaluates its infectivity by Schistosoma mansoni in 5264 specimens collected in the municipality of Juiz de Fora, Minas Gerais, Brazil. Of the 31 locations studied, 6 were reservoirs, 11 rudimentary holding ponds, 7 irrigation ditches, 5 lakes, 1 ornamental pond, and 1 waterfall. Intermediate hosts were found only in the rudimentary ponds and ditches, which were 100% positive. Using morphological and molecular analysis techniques, B. tenagophila, B. peregrina, and B. straminea were identified. This is the first report of B. stramínea in the municipality, and evaluation of its infective potential revealed susceptibility of 25.4%. Although we did not find specimens of Biomphalaria infected by S. mansoni, the data obtained indicate the presence of intermediate hosts, especially in the irrigation ditches in Juiz de Fora, and their proximity to contaminated areas.


Asunto(s)
Biomphalaria/clasificación , Vectores de Enfermedades/clasificación , Schistosoma mansoni , Animales , Biomphalaria/parasitología , Brasil , Densidad de Población
15.
Appl Environ Microbiol ; 70(11): 6657-64, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15528531

RESUMEN

Thirty-three strains of Brevibacillus laterosporus, including three novel strains isolated from Brazilian soil samples, were examined for genetic variability by the use of different PCR-based methods. Molecular markers that could characterize bacterial strains with regards to their pathogenic potential were investigated. In addition, toxicity was assessed by the use of insects belonging to the orders Lepidoptera and Coleoptera and the mollusk Biomphalaria glabrata. Among the targets tested, Biomphalaria glabrata demonstrated the highest degree of sensitivity to B. laterosporus, with some strains inducing 90 to 100% mortality in snails aged 3 and 12 days posteclosion. Larvae of the coleopteron Anthonomus grandis were also susceptible, presenting mortality levels of between 33 and 63%. Toxicity was also noted towards the lepidopteron Anticarsia gemmatalis. In contrast, no mortality was recorded among test populations of Tenebrio molitor or Spodoptera frugiperda. The application of intergenic transcribed spacer PCR and BOX-PCR generated 15 and 17 different genotypes, respectively. None of the molecular techniques allowed the identification of a convenient marker that was associated with any entomopathogenic phenotype. However, a 1,078-bp amplicon was detected for all strains of B. laterosporus when a primer for amplification of the BOXA1R region was used. Similarly, a 900-bp amplicon was generated from all isolates by use of the primer OPA-11 for randomly amplified polymorphic DNA analysis. These amplicons were not detected for other phenotypically related Brevibacillus species, indicating that they represent markers that are specific for B. laterosporus, which may prove useful for the isolation and identification of new strains of this species.


Asunto(s)
Bacillus/clasificación , Bacillus/genética , Variación Genética , Control Biológico de Vectores , Animales , Bacillus/crecimiento & desarrollo , Biomphalaria/crecimiento & desarrollo , Escarabajos/crecimiento & desarrollo , ADN Espaciador Ribosómico/análisis , Marcadores Genéticos , Larva/crecimiento & desarrollo , Lepidópteros/crecimiento & desarrollo , Reacción en Cadena de la Polimerasa , Técnica del ADN Polimorfo Amplificado Aleatorio , Esporas Bacterianas/crecimiento & desarrollo
16.
Mem Inst Oswaldo Cruz ; 99(4): 421-4, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15322633

RESUMEN

From complete mitochondrial DNA sequence of Fasciola hepatica available in Genbank, specific primers were designed for a conserved and repetitive region of this trematode. A pair of primers was used for diagnosis of infected Lymnaea columella by F. hepatica during the pre-patent period simultaneously with another pair of primers which amplified the internal transcribed spacer (ITS) region of rDNA from L. columella in a single Multiplex-PCR. The amplification generated a ladder band profile specific for F. hepatica. This profile was observed in positive molluscs at different times of infection, including adult worms from the trematode. The Multiplex-PCR technique showed to be a fast and safe tool for fascioliasis diagnosis, enabling the detection of F. hepatica miracidia in L. columella during the pre-patent period and identification of transmission areas.


Asunto(s)
Fasciola hepatica/aislamiento & purificación , Lymnaea/parasitología , Reacción en Cadena de la Polimerasa/normas , Animales , ADN de Helmintos/genética , ADN Mitocondrial/genética , ADN Espaciador Ribosómico/genética , Fasciola hepatica/genética , Lymnaea/genética , Reacción en Cadena de la Polimerasa/métodos
17.
Mem. Inst. Oswaldo Cruz ; 99(4): 421-424, Jun. 2004. ilus
Artículo en Inglés | LILACS | ID: lil-363861

RESUMEN

From complete mitochondrial DNA sequence of Fasciola hepatica available in Genbank, specific primers were designed for a conserved and repetitive region of this trematode. A pair of primers was used for diagnosis of infected Lymnaea columella by F. hepatica during the pre-patent period simultaneously with another pair of primers which amplified the internal transcribed spacer (ITS) region of rDNA from L. columella in a single Multiplex-PCR. The amplification generated a ladder band profile specific for F. hepatica. This profile was observed in positive molluscs at different times of infection, including adult worms from the trematode. The Multiplex-PCR technique showed to be a fast and safe tool for fascioliasis diagnosis, enabling the detection of F. hepatica miracidia in L. columella during the pre-patent period and identification of transmission areas.


Asunto(s)
Animales , Fasciola hepatica , Lymnaea , Reacción en Cadena de la Polimerasa , ADN de Helmintos , ADN Mitocondrial , ADN Espaciador Ribosómico
18.
Mem Inst Oswaldo Cruz ; 97(3): 407-10, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12048573

RESUMEN

Fascioliasis is a parasitic disease of domestic ruminants that occurs worldwide. The lymnaeid intermediate hosts of Fasciola hepatica include Lymnaea columella, which is widely distributed in Brazil. A colony of L. columella from Belo Horizonte, MG, was reared in our laboratory to be used in studies of the F. hepatica life cycle, the intermediate host-parasite relationship and development of an anti-helminthic vaccine. In the first experiment 1,180 snails were exposed to miracidia of F. hepatica eggs removed from the biliary tracts of cattle from the State of Rio Grande do Sul. In the second and third experiments the snails were exposed to miracidia that had emerged from F. hepatica eggs from Uruguay, maintained in rabbits. The rates of infection in the first, second and third experiments were 0, 42.1 and 0% respectively. Over 15,806 metacercariae were obtained and stored at 4 degrees C. Four rabbits weighing 1.5 kg each were infected with 32-44 metacercariae and two with 200. Three rabbits begin to eliminate eggs of the parasite in the feces from 84 days after infection onwards. The biological cycle of F. hepatica in L. columella and the rabbit was completed within 124 days.


Asunto(s)
Fasciola hepatica/crecimiento & desarrollo , Estadios del Ciclo de Vida/fisiología , Lymnaea/parasitología , Animales , Brasil , Bovinos , Interacciones Huésped-Parásitos , Conejos , Uruguay
19.
Mem. Inst. Oswaldo Cruz ; 97(3): 407-410, Apr. 2002. tab
Artículo en Inglés | LILACS | ID: lil-307961

RESUMEN

Fascioliasis is a parasitic disease of domestic ruminants that occurs worldwide. The lymnaeid intermediate hosts of Fasciola hepatica include Lymnaea columella, which is widely distributed in Brazil. A colony of L. columella from Belo Horizonte, MG, was reared in our laboratory to be used in studies of the F. hepatica life cycle, the intermediate host-parasite relationship and development of an anti-helminthic vaccine. In the first experiment 1,180 snails were exposed to miracidia of F. hepatica eggs removed from the biliary tracts of cattle from the State of Rio Grande do Sul. In the second and third experiments the snails were exposed to miracidia that had emerged from F. hepatica eggs from Uruguay, maintained in rabbits. The rates of infection in the first, second and third experiments were 0, 42.1 and 0 percent respectively. Over 15,806 metacercariae were obtained and stored at 4ºC. Four rabbits weighing 1.5 kg each were infected with 32-44 metacercariae and two with 200. Three rabbits begin to eliminate eggs of the parasite in the feces from 84 days after infection onwards. The biological cycle of F. hepatica in L. columella and the rabbit was completed within 124 days


Asunto(s)
Animales , Bovinos , Conejos , Fasciola hepatica , Estadios del Ciclo de Vida , Lymnaea , Brasil , Interacciones Huésped-Parásitos , Uruguay
20.
Rev. Inst. Med. Trop. Säo Paulo ; 42(5): 291-4, Sept.-Oct. 2000. ilus, tab
Artículo en Inglés | LILACS | ID: lil-270232

RESUMEN

In order to determine Schistosoma mansoni infection rates in Biomphalaria tenagophila and B. straminea, low stringency polymerase chain reaction (LS-PCR) technique was used as a complementary method to light exposure technique. LS-PCR has already been standardized in our laboratory to detect the trematode DNA in B. glabrata. Higher S. mansoni infection rates were detected using conventional method and LS-PCR. The parasite DNA profile was detected in both species after 7-day exposure to miracidia, using LS-PCR. This technique enables early detection of schistosomiasis transmission focuses, in endemic areas, before the beginning of cercariae shedding


Asunto(s)
Animales , Biomphalaria/parasitología , Reacción en Cadena de la Polimerasa/métodos , Schistosoma mansoni/fisiología , Interacciones Huésped-Parásitos , Luz
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