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Sele o genética de Biomphalaria glabrata e Biomphalaria tenagophila visando a altera o da suscetibilidade e resistência ao Schistosoma mansoni
Zuim Nádia Regina Borim,Zanotti-Magalh?es Eliana Maria,Magalh?es Luiz Augusto,Linhares Arício Xavier
Revista da Sociedade Brasileira de Medicina Tropical , 2005,
Abstract: Gera es de Biomphalaria glabrata e Biomphalaria tenagophila selecionadas geneticamente para resistência e suscetibilidade ao Schistosoma mansoni das linhagens BH e SJ foram utilizadas no estudo da adapta o do trematódeo ao hospedeiro intermediário. As gera es dos planorbídeos foram obtidas por autofecunda o dos moluscos que se apresentaram suscetíveis ou resistentes após a exposi o aos miracídios de Schistosoma mansoni. Para Biomphalaria glabrata foram obtidas as gera es: Parental, F1S (Suscetível), F1R (Resistente), F2S e F2R. Para a Biomphalaria tenagophila foram estudadas as gera es: Parental, F1S, F1R e F50S. A compara o das taxas de infec o apresentadas pelas diferentes gera es mostrou que, em ambas as espécies, o aumento da suscetibilidade foi mais facilmente obtido do que o aumento da resistência. A dificuldade em aumentar a resistência do molusco ao S. mansoni tem fortes implica es epidemiológicas.
Suscetibilidade à infec??o pelo Schistosoma mansoni, de Biomphalaria glabrata e Biomphalaria tenagophila do Distrito Federal, Brasil
Coimbra Jr.,Carlos Everaldo A.;
Revista de Saúde Pública , 1981, DOI: 10.1590/S0034-89101981000500005
Abstract: the susceptibility of bimphalaria glabrata and biomphalaria tenagophila, collected in the federal district of brazil, to infection by schistosoma mansoni is here studied. the author also relates the geographical distribution of the snails' habitats and their living conditions to the source of the autochthonous cases known in the federal district.
Suscetibilidade de biomphalaria glabrata, B. straminea e B. tenagophila a diferentes cepas de schistosoma mansoni
Dias, Luiz Candido de Souza;Ueta, Marlene Tiduko;Guaraldo, Ana Maria Aparecida;
Revista do Instituto de Medicina Tropical de S?o Paulo , 1987, DOI: 10.1590/S0036-46651987000400004
Abstract: the susceptibility of 3 species of snails from, brazil, b. glabrata (minas gerais - mg - and s?o paulo - sp - states), b. tenagophila (sp) and b. straminea (sp) to experimental infection with 4 human (map, pth vph, and ouh) and 2 rodent (ptr and vpr both from sp) isolates of s. mansoni was studied. snails of each species were exposed individually to 10 miracidia and observed during a 70 day experimental period for mortality, sporocyst development and number of snails shedding cercariae. the b. glabrata from mg -was found to be susceptible to map (mg) and 5 from sp (pth, vph, ouh, ptr and vpr). the b. glabrata from sp -was found to be susceptible to map, ouh and vpr. high mortalites were observed among b. glabrata from sp. the b. stramlnea was found to be susceptible to map (only sporocysts), ouh and vpr parasites; mortality rates were lower in this species of snail than in the other species tested. b. tenagophila from sp was found to be susceptible only to sympatric strains, but with low infection rates. the results indicate the importance of transmission of schistosome by human migration from s?o paulo to other brazilian areas.
Sele??o de linhagens de Biomphalaria tenagophila e Biompnalaria glabrata visando maior suscetibilidade ao Schistosoma mansoni
Santana,José Valfrido de; Magalh?es,Luiz Augusto; Rangel,Humberto de Araújo;
Revista de Saúde Pública , 1978, DOI: 10.1590/S0034-89101978000100008
Abstract: populations of b. tenagophila and b. glabrata highly susceptible to strains s. mansoni from the valley of the paraíba do sul river (state of s. paulo) and from belo horizonte (state of minas gerais), were obtained after four generations using a schedule of individual selections in self-fertilized populations. the rapid genetic gains in susceptibility show that molluscan susceptibility to schistosomiasis infection is highly inheritable, and is apparently conditioned by few genes.
Sele??o genética de Biomphalaria glabrata e Biomphalaria tenagophila visando a altera??o da suscetibilidade e resistência ao Schistosoma mansoni
Zuim, Nádia Regina Borim;Zanotti-Magalh?es, Eliana Maria;Magalh?es, Luiz Augusto;Linhares, Arício Xavier;
Revista da Sociedade Brasileira de Medicina Tropical , 2005, DOI: 10.1590/S0037-86822005000500004
Abstract: generations of biomphalaria glabrata and biomphalaria tenagophila selected genetically for resistance and susceptibility to schistosoma mansoni of strains bh and sj were used in a study of the trematode adaptation to the intermediate host. descendants of the planorbids were obtained by self-fertilization of the mollusks that became susceptible or resistant after exposure to the miracidia of schistosoma mansoni. for biomphalaria glabrata they were obtained from the following generations: parental, f1s (susceptible), f1r (resistant), f2s and f2r. for biomphalaria tenagophila the studied generations were: parental, f1s, f1r and f50s. the comparison of the infection rates presented by the different generations showed that the increase in susceptibility was more easily obtained in both species. the difficulty in increasing the resistance of the mollusks to schistosoma mansoni has important epidemiologic implications.
Development of Schistosoma mansoni in Biomphalaria tenagophila, Biomphalaria straminea and Biomphalaria glabrata
Souza, Cecilia Pereira de;Cunha, Rita de Cássia Palma;Andrade, Zilton A.;
Revista do Instituto de Medicina Tropical de S?o Paulo , 1995, DOI: 10.1590/S0036-46651995000300004
Abstract: a comparative study of the development of schistosoma mansoni during the intra-molluscan phase was made by means of histological sections of biomphalaria tenagophila, b. straminea and b. glabrata from brazil. two hundred snails of each species were individually exposed to 50 miracidia of the s. mansoni, al line. no larvae were observed in the snails fixed 72 h after exposure. in specimens shedding cercariae, 31 days after exposure tissue reactions encapsulating the larvae were seen in b. tenagophila and b. straminea, in the head-foot, mantle collar and renal ducts. no tissue reactions occurred in the digestive glands of these two species. in b. glabrata the presence of numerous sporocysts and cercariae without tissue reactions was observed in the digestive gland, and other organs. the levels of infection of the snails and the average numbers of cercariae shed per day were 32.6% and 79±90 respectively for b. tenagophila, 11.3% and 112±100 for b. straminea and 75.3% and 432±436 for b. glabrata. the lower levels of infection and average numbers of cercariae shed by b. tenagophila and b. straminea are thus related to their more potent internal defense systems.
The effect of early infection with Echinostoma paraensei on the interaction of Schistosoma mansoni with Biomphalaria glabrata and Biomphalaria tenagophila
Garcia, Juberlan Silva;Maldonado Junior, Arnaldo;Bidau, Cláudio Juan;Corrêa, Ligia dos Reis;Lanfredi, Reinalda Marisa;Coelho, Paulo Marcos Zech;
Memórias do Instituto Oswaldo Cruz , 2010, DOI: 10.1590/S0074-02762010000400026
Abstract: infection caused by the trematode echinostoma paraensei has been shown to interfere in the natural resistance to infection by schistosoma mansoni. biomphalaria glabrata is susceptible to infection, while taim isolate biomphalaria tenagophila is resistant to infection by s. mansoni. these two snail species were assessed for infection with e. paraensei two days after exposure to s. mansoni miracidia. the number of b. tenagophila and b. glabrata infected with e. paraensei was lower in co-infected group, suggesting an antagonistic relationship. b. glabrata showed an increase in its susceptibility to s. mansoni, whereas b. tenagophila maintained its refractoriness to s. mansoni infection. weekly comparisons made between the e. paraensei cercariae released from b. tenagophila and b. glabrata mono-infected snails revealed no quantitative differences. in contrast, s. mansoni cercariae released were higher in the b. glabrata co-infected group. mortality rates were significantly greater in both species pertaining to co-infected group and unexpected mortalities were also observed in b. tenagophila exposed only to s. mansoni miracidia. our study revealed that the b. tenagophila taim isolate is susceptible to e. paraensei infection, although infection did not alter its resistance to s. mansoni infection.
Compara o da capacidade ovipositora entre 3 espécies de moluscos planorbidae, hospedeiros intermediários do Schistosoma mansoni no Brasil, Biomphalaria glabrata (SAY, 1818), Biomphalaria tenagophila (D'ORBIGNY, 1835) E Biomphalaria straminea (LUTZ, 1918)  [cached]
Odair Genaro
Semina : Ciências Sociais e Humanas , 1979, DOI: 10.5433/
Abstract: The author studied the reproductive potential of Biomphalaria glabrata, Biomphalaria tenagophila and Biomphalaria straminea and the results obtained were compared amongst them During a period of 30 days, between March and April, the number of egg-masses and the number of eggs in each of egg-masses, was recorded daily, in 20 samples of each species studied in the laboratory. The obtained strains of B. glabrata and B. tenagophila are originally from Londrina, Parana and the strain of B. straminea is originated from Limoeiro do Norte, Ceara. The results obtained which were different for each species, were significant in the relation total number of eggs produced during the mentioned period, considering that B. glabrata produced a total number of 16.314 eggs, B. straminea 6.611 and B. teangophila 2.049. Therefore, infering the medium number of eggs per mass and the medium number of eggs per snail B. glabrata showed to be potencially more abierfor reproduction than the other species studied. With reference to B. straminea this species showed in our experiments to be more fecund than B. tenagophila, becoming perhaps, the second more important intermediate host of Schistosoma mansoni in Brazil, fact which is reinforced, by its large distribution in the Northeast of Brazil.Biomphalaria tenagophila Biomphalaria straminea cujos resultados obtidos foram comparados entre si Assim, durante um período de 30 dias, compreendido entre os meses de mar o e abril, registrou-se diariamente o número de cápsulas ovígeras e o número de ovos de cada uma delas para 20 exemplares de cada espécie em quest o, em condi es de laboratório. As cepas obtidas de B. glabrata e B. tenagophila s o originárias de Londrina, Paraná e a cepa de B. straminea oriunda de Limoeiro do Norte, Ceará. Os resultados obtidos, diferentes para cada espécie foram significativos em rela o ao número total de ovos produzidos no período mencionado, considerando-se que B. glabrata produziu um total de 16.314 ovos, B. straminea 6.611 eK. tenagophila 2. lnferindo-se daí o número médio de ovos por cápsula e o número médio de ovos por caramujo, a B. glabrata mostrou-se potencialmente mais capaz para a reprodu o do que as outras espécies em quest o. No que se refere a B. straminea esta espécie revelou-se em nosso experimento ser mais fecunda que B. tenagophila, tornando-se talvez o segundo mais importante hospedeiro intermediário do Schistosoma mansoni no Brasil, a cujo favor fala sua ampla distribui o no Nordeste Brasileiro.
Differential lectin labelling of circulating hemocytes from Biomphalaria glabrata and Biomphalaria tenagophila resistant or susceptible to Schistosoma mansoni infection
Martins-Souza, RL;Pereira, CAJ;Martins Filho, OA;Coelho, PMZ;Corrêa Jr, A;Negr?o-Corrêa, D;
Memórias do Instituto Oswaldo Cruz , 2006, DOI: 10.1590/S0074-02762006000900029
Abstract: lectins/carbohydrate binding can be involved in the schistosoma mansoni recognition and activation of the biomphalaria hemocytes. therefore, expression of lectin ligands on biomphalaria hemocytes would be associated with snail resistance against s. mansoni infection. to test this hypothesis, circulating hemocytes were isolated from b. glabrata bh (snail strain highy susceptible to s. mansoni), b. tenagophila cabo frio (moderate susceptibility), and b. tenagophila taim (completely resistant strains), labelled with fitc conjugated lectins (cona, pna, sba, and wga) and analyzed under fluorescence microscopy. the results demonstrated that although lectin-labelled hemocytes were detected in hemolymph of all snail species tested, circulating hemocytes from both strains of b. tenagophila showed a larger number of lectin-labelled cells than b. glabrata. moreover, most of circulating hemocytes of b. tenagophila were intensively labelled by lectins pna-fitc and wga-fitc, while in b. glabrata small hemocytes were labeled mainly by cona. upon s. mansoni infection, lectin-labelled hemocytes almost disappeared from the hemolymph of taim and accumulated in b. glabrata bh. the role of lectins/carbohydrate binding in resistance of b. tengophila infection to s. mansoni is still not fully understood, but the data suggest that there may be a correlation to its presence with susceptibility or resistance to the parasite.
Alguns aspectos da biologia de Biomphalaria glabrata (Say, 1818) e Biomphalaria tenagophila (D'Orbigny, 1835) (Pulmonata, Planorbidae): I - Dura??o do período embrionário
Kawazoe,Urara;
Revista de Saúde Pública , 1976, DOI: 10.1590/S0034-89101976000100005
Abstract: the incubation periods of biomphalaria glabrata and biomphalaria tenagophila were compared during one year, in the laboratory. the average time for eggs hatching was 7,6 and 8,0 days for biomphalaria glabrata and biomphalaria tenagophila, respectively; the difference was not significant at the 5% level. the fastest development of the eggs was verified in the summer when the average water temperature was approximately 28°c. the analysis of the correlation coeficient showed that the influence of temperature on the egg development period was not strong: biomphalaria glabrata showed best correlation with minimum air temperature (36,2%) and with water temperature (36,0%), while biomphalaria tenagophila correlated best with minimum air temperature (27,0%).
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