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Search Results: 1 - 10 of 16929 matches for " Liana Konovaloff;Carvalho "
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Detection of Lymnaea columella infection by Fasciola hepatica through Multiplex-PCR
Magalh?es, Kelly Grace;Passos, Liana Konovaloff Jannotti;Carvalho, Omar dos Santos;
Memórias do Instituto Oswaldo Cruz , 2004, DOI: 10.1590/S0074-02762004000400013
Abstract: 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.
Resistência de Biomphalaria peregrina de Santa Rita do Sapucaí, Minas Gerais, a infec??o com três cepas de Schistosoma mansoni
Souza, Cecília Pereira de;Passos, Liana Konovaloff Janotti;Carvalho, Omar dos Santos;
Memórias do Instituto Oswaldo Cruz , 1988, DOI: 10.1590/S0074-02761988000400009
Abstract: the descendants of the planorbid snail biomphalaria peregrina, collected in the region of santa rita do sapucaí, minas gerais, brazil, were exposed to miracidia of three strains of schistosoma mansoni: "le" strain from belo horizonte, state of minas gerais; "sj", strain from s?o josé dos campos, state of s?o paulo and "al" strain from state of alagoas. of 300 snails exposed to miracidia of the three strains, none was infected. on the other hand, 300 biomphalaria glabrata of the control groups showed infection rates of 61.1 to 95.3% with three strains. the mortality rates of b. peregrina and b. glabrata were 20% and 28%, respectively.
First report on the presence of Biomphalaria straminea in the municipality of Jaboticatubas, State of Minas Gerais, Brazil
Massara Cristiano Lara,Carvalho Omar dos Santos,Caldeira Roberta Lima,Jannotti-Passos Liana Konovaloff
Memórias do Instituto Oswaldo Cruz , 2002,
Abstract: This is the first report on occurrence of Biomphalaria straminea in the district of S o José de Almeida (municipality of Jaboticatubas) State of Minas Gerais, Brazil. The presence of B. glabrata and B. tenagophila had already been reported in this area. Such municipality is part of the metropolitan region of Belo Horizonte and comprises 60% of the Tourist Complex of Serra do Cipó. Since the 1950s throughout the 1990s, a schistosomiasis prevalence ranging from 15 to 40% has been observed. Although no B. straminea specimen has been found naturally infected in the region, descendants of these snails collected in the area, showed to be experimentally susceptible to Schistosoma mansoni infection reaching rates from 14.6 to 28.6%. Even not being found naturally infected, in the State of Minas Gerais, the possibility that the species B. straminea may keep endemicity foci of schistosomiasis should be regarded, as in the Northeastern region of Brazil where the high density of this planorbid and the social-economic and sanitary conditions enable to the transmission.
First report on the presence of Biomphalaria straminea in the municipality of Jaboticatubas, State of Minas Gerais, Brazil
Massara, Cristiano Lara;Carvalho, Omar dos Santos;Caldeira, Roberta Lima;Jannotti-Passos, Liana Konovaloff;Schall, Virgínia Torres;
Memórias do Instituto Oswaldo Cruz , 2002, DOI: 10.1590/S0074-02762002000900007
Abstract: this is the first report on occurrence of biomphalaria straminea in the district of s?o josé de almeida (municipality of jaboticatubas) state of minas gerais, brazil. the presence of b. glabrata and b. tenagophila had already been reported in this area. such municipality is part of the metropolitan region of belo horizonte and comprises 60% of the tourist complex of serra do cipó. since the 1950s throughout the 1990s, a schistosomiasis prevalence ranging from 15 to 40% has been observed. although no b. straminea specimen has been found naturally infected in the region, descendants of these snails collected in the area, showed to be experimentally susceptible to schistosoma mansoni infection reaching rates from 14.6 to 28.6%. even not being found naturally infected, in the state of minas gerais, the possibility that the species b. straminea may keep endemicity foci of schistosomiasis should be regarded, as in the northeastern region of brazil where the high density of this planorbid and the social-economic and sanitary conditions enable to the transmission.
Angiostrongylus cantonensis (Nematode: Metastrongyloidea) in molluscs from harbour areas in Brazil
Carvalho, Omar dos Santos;Scholte, Ronaldo Guilherme Carvalho;Mendon?a, Cristiane Lafeta Furtado de;Passos, Liana Konovaloff Jannotti;Caldeira, Roberta Lima;
Memórias do Instituto Oswaldo Cruz , 2012, DOI: 10.1590/S0074-02762012000600006
Abstract: 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.
Biomphalaria molluscs (Gastropoda: Planorbidae) in Rio Grande do Sul, Brazil
Pepe, Michele Soares;Caldeira, Roberta Lima;Carvalho, Omar dos Santos;Muller, Gertrud;Jannotti-Passos, Liana Konovaloff;Rodrigues, Alice Pozza;Amaral, Hugo Leonardo;Berne, Maria Elisabeth Aires;
Memórias do Instituto Oswaldo Cruz , 2009, DOI: 10.1590/S0074-02762009000500020
Abstract: the present study was aimed at characterising biomphalaria species using both morphological and molecular (pcr-rflp) approaches. the specimens were collected in 15 localities in 12 municipalities of the southern region of the state of rio grande do sul, brazil. the following species were found and identified: biomphalaria tenagophila guaibensis, biomphalaria oligoza and biomphalaria peregrina. specimens of the latter species were experimentally challenged with the le schistosoma mansoni strain, which showed to be refractory to infection.
Hybridism between Biomphalaria cousini and Biomphalaria amazonica and its susceptibility to Schistosoma mansoni
Teodoro, Tatiana Maria;Jannotti-Passos, Liana Konovaloff;Carvalho, Omar dos Santos;Grijalva, Mario J;Baús, Esteban Guilhermo;Caldeira, Roberta Lima;
Memórias do Instituto Oswaldo Cruz , 2011, DOI: 10.1590/S0074-02762011000700011
Abstract: molecular techniques can aid in the classification of biomphalaria species because morphological differentiation between these species is difficult. previous studies using phylogeny, morphological and molecular taxonomy showed that some populations studied were biomphalaria cousini instead of biomphalaria amazonica. three different molecular profiles were observed that enabled the separation of b. amazonica from b. cousini. the third profile showed an association between the two and suggested the possibility of hybrids between them. therefore, the aim of this work was to investigate the hybridism between b. cousini and b. amazonica and to verify if the hybrids are susceptible to schistosoma mansoni. crosses using the albinism factor as a genetic marker were performed, with pigmented b. cousini and albino b. amazonica snails identified by polymerase chain reaction-restriction fragment length polymorphism. this procedure was conducted using b. cousini and b. amazonica of the type locality accordingly to paraense, 1966. in addition, susceptibility studies were performed using snails obtained from the crosses (hybrids) and three s. mansoni strains (le, sj, al). the crosses between b. amazonica and b. cousini confirmed the occurrence of hybrids. moreover, hybrids can be considered potential hosts of s. mansoni because they are susceptible to le, sj and al strains (4.4%, 5.6% and 2.2%, respectively). these results indicate that there is a risk of introducing schistosomiasis mansoni into new areas.
Biomphalaria tenagophila: dynamics of populations of resistant and susceptible strains to Schistosoma mansoni, with or without pressure of the parasite
Rosa, Florence Mara;Godard, Ana Lúcia Brunialti;Negr?o-Correa, Deborah;Rodrigues, Horácio Antonio;Carvalho, Omar dos Santos;Caldeira, Roberta Lima;Teles, Horácio Manoel Santana;Maciel, Engels;Jannotti-Passos, Liana Konovaloff;Coelho, Paulo Marcos Zech;
Memórias do Instituto Oswaldo Cruz , 2006, DOI: 10.1590/S0074-02762006000900038
Abstract: resistant (taim, rs) and susceptible albino (joinville, sc) biomphalaria tenagophila populations were kept together, at different proportions, throughout a 18-month-period. some of the snail groups were submitted to schistosoma mansoni infection. the targets of this study were (a) to analyze the populational dynamics among resistant and susceptible individuals to s. mansoni; (b) to study the resistance phenotype in descendants of cross-breeding; (c) to observe whether the parasite could exert any kind of selection in those snail populations. throughout the experiment it could be observed that the susceptible b. tenagophila strain (joinville) underwent a selective pressure of the parasite that was negative, since the individuals showed a high mortality rate. although b. tenagophila (taim) population presented a higher mortality rate without pressure of the parasite, this event was compensated by a reproductive capacity. b. tenagophila taim was more fecund than b. tenagophila joinville and was able to transmit the resistance character to their descendants. f1 generation obtained by cross-breeding between resistant and susceptible lineages was completely resistant to s. mansoni infection, irrespective of the taim proportion. moreover, less than 5% of f2 progeny were susceptible to s. mansoni infection.
Susceptibility of Biomphalaria tenagophila and Biomphalaria straminea to Schistosoma mansoni infection detected by low stringency polymerase chain reaction
JANNOTTI-PASSOS, Liana Konovaloff;SOUZA, Cecilia Pereira de;
Revista do Instituto de Medicina Tropical de S?o Paulo , 2000, DOI: 10.1590/S0036-46652000000500010
Abstract: 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.
Susceptibility of Biomphalaria tenagophila and Biomphalaria straminea to Schistosoma mansoni infection detected by low stringency polymerase chain reaction
JANNOTTI-PASSOS Liana Konovaloff,SOUZA Cecilia Pereira de
Revista do Instituto de Medicina Tropical de S?o Paulo , 2000,
Abstract: 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.
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