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Sample records for biomphalaria straminea dunker

  1. Growth changes induced by gamma radiation on Biomphalaria straminea (Dunker, 1848

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    Motta Mauricy A da

    1999-01-01

    Full Text Available Doses of 60Co gamma radiation with 2.5; 5; 7.5; 10; 15; 20; 25; 30; 35; 40; 45; 50; 55; 60; 80; 160; 320 and 640 Gy were applied to 1,080 snails Biomphalaria straminea, an intermediate host of Schistosoma mansoni, divided in groups containing 30 mollusks. In addition, 60 non irradiated snails were kept as control. Fifty percent of the population was kept in colonies (allowing cross fertilization while the other half was maintained in sexual isolation (allowing self fertilization and during one month their growth was observed through the daily measurement of the shell diameter. Results showed that after 20 Gy doses the growth in shell diameter of irradiated snails was greater than that of the control group after 30 days. At this dose the snail size was the greatest, among all isolated groups. The 80 Gy doses also induced the final shell diameter of isolated snails to be greater then that observed in the control groups. As this effect was most evident among the isolated snails, a possible hormonal role may have been involved in the observed phenomena, which is under investigation with the objective of identifying any future applications that this could have to schistosomiasis control.

  2. Susceptibility of Biomphalaria straminea (Dunker, 1848) from Serra da Mesa Dam, Goiás, Brazil to infection with three strains of Schistosoma mansoni Sambon, 1907.

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    Fernandez, Monica Ammon; Thiengo, Silvana Carvalho

    2002-01-01

    Ecological changes from water resources development projects often affect the epidemiology of water-associated diseases. In order to investigate the occurrence and distribution of freshwater snails of medical and veterinary importance in the area of influence of the Serra da Mesa Hydroelectric a survey has been performed since 1997 and revealed the occurrence of well-established populations of Biomphalaria straminea (Dunker, 1848) in the 8 municipalities surrounding the lake. Areas of epidemiologic risk for schistosomiasis were selected and studies of parasite-mollusc compatibility were undertaken using specimens from 19 populations of B. straminea and 3 strains (CM, EC and PB) originally isolated from B. straminea. Among 1,135 specimens used 15 became infected (infection index of 1.3%) and 8 populations were susceptible to the schistosome strains: B. straminea from Campinorte (Castelão, susceptible to CM and EC strains, and Planeta Agua, EC strain), Colinas (Tocantinzinho river, CM and EC strains), Minaçu (Canabrava river, EC strain), Niquelândia (Codemin, CM and PB strains, and Almas river, CM strain), Uruaçu (touristic area, PB strain) and Santa Rita do Novo Destino (Maranhão river, CM and EC strains). These results, associated with marked social and ecological changes occurred, strongly suggest the possibility of B. straminea coming to act as a vector of schistosomiasis in the studied area.

  3. Malacological assessment and natural infestation of Biomphalaria straminea (Dunker, 1848 by Schistosoma mansoni (Sambon, 1907 and Chaetogaster limnaei (K. von Baer, 1827 in an urban eutrophic watershed

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    M. Callisto

    Full Text Available The objective of this study was to perform a malacological assessment at the Ibirité reservoir watershed in the metropolitan region of Belo Horizonte (Minas Gerais and to evaluate the natural infestation rate of Biomphalaria straminea (Gastropoda: Planorbidaeby Schistosoma mansoni (Platyhelminthes: Trematoda and Chaetogaster limnaei (Oligochaeta: Naididae. The samples were collected from July to August 2002. The B. straminea individuals collected were kept in the laboratory; the natural infestation rate by S. mansoni and C. limnaei was assessed weekly. The malacological assessment identified fivemollusk species present in the Ibirité reservoir watershed: B. straminea, Physa marmorata, Lymnea sp., Melanoides tuberculatus,and Pomacea austrum. Laboratory observations showed that the B. straminea individuals were infected by C. limnaei rather than S. mansoni. Although there was no infection of B. straminea by S. mansoni,presence of B. straminea in itself merits close attention due to possible risk of human schistosomiasis by the local population.

  4. Comparative study of the fecundity and fertility of Biomphalaria glabrata (Say, 1818 and Biomphalaria straminea (Dunker, 1848 in a laboratory through self-fertilization and cross-fertilization Estudo comparativo da fecundidade e fertilidade de Biomphalaria glabrata (Say, 1818 e Biomphalaria straminea (Dunker, 1848 em laboratório por autofecundação e fecundação cruzada

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    Marta Julia F.S. Costa

    2004-06-01

    Full Text Available The aim of this study was to compare the fecundity and fertility of B. glabrata and B. straminea by cross- and self-fertilization. To attain this objective, laboratory-raised strains of B. glabrata and B. straminea were used. The former originated from natural breeding grounds in the municipality Paulista, state of Pernambuco, Brazil. The latter originated from irrigation ditches in the municipality of Petrolândia, in the same state. Snail populations of B. glabrata and B. straminea were maintained for 240 days in laboratory. Their fecundity was evaluated by noting the number of egg-masses, eggs and eggs per mass. Their fertility was evaluated by the number of viable eggs and the hatching rate. B. straminea was markedly more fecund than B. glabrata through cross- and self-fertilization, namely: greater egg-mass; higher egg production and more eggs per mass. Regarding fertility, there seemed to be no preferential period for occlusion to occur or a trend in the rhythm of producing viable eggs.O objetivo deste trabalho foi comparar a fecundidade e fertilidade de Biomphalaria glabrata e Biomphalaria straminea em condições de laboratório considerando a autofecundação e a fecundação cruzada. Durante oito meses, foram registrados em laboratório, o número de cápsulas ovíferas (desovas, ovos por cápsula ovífera, ovos totais, taxa de eclosão e percentual de ovos férteis dos moluscos criados individualmente e agrupados. Foram utilizados exemplares de B. glabrata de Paulista, PE e B. straminea oriunda de Petrolândia, PE. As observações foram divididas por faixa etária no periódo de 0 a 240 dias. Os resultados obtidos neste trabalho mostram que B. straminea apresenta um potencial reprodutivo maior do que B. glabrata, tanto para moluscos criados em grupo quanto para os criados individualmentes. A comparação dos valores encontrados para fecundidade dentro da mesma espécie sugere que a autofecundação como estratégia reprodutiva,

  5. Development of Schistosoma mansoni in Biomphalaria tenagophila, Biomphalaria straminea and Biomphalaria glabrata Desenvolvimento do Schistosoma mansoni em Biomphalaria tenagophila, Biomphalaria straminea e Biomphalaria glabrata

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    Cecilia Pereira de Souza

    1995-06-01

    Full Text Available 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.Foi feito estudo comparativo do desenvolvimento do Schistosoma mansoni na fase intra-molusco, através de cortes histológicos, em Biomphalaria tenagophila, B. straminea e B. glabrata. Duzentos moluscos de cada espécie foram expostos individualmente a 50 miracídios de S. mansoni da linhagem AL. Nenhuma larva foi observada nos exemplares fixados 72 horas após a exposição. Nos exemplares eliminando cercárías, 31 dias após a exposição, foram observadas reações teciduais de encapsulamento de larvas em B. tenagophila e B. straminea, na região cefalopodal, colar do manto e dutos renais. Nas glândulas digestivas das duas espécies não foram observadas reações. Em B. glabrata foi registrada a presença de numerosos esporocistos e cercárias sem reação tecidual na gl

  6. Biomphalaria straminea no Peru e sua suscetibilidade a cepas brasileiras de Schistosoma mansoni

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    C.A. Cuba Cuba

    1977-12-01

    Full Text Available Em Maio de 1973, um dos autores (C.A.C. coletou na localidade de Imacita, Província de Bagua, Departamento de Amazonas, vários espécimes de Biomphalaria straminea (Dunker, 1848, uma espécie que, até então, não havia sido assinalada no Peru. Descendentes destes indivíduos foram submetidos a provas de suscetibilidade às cepas BH e SJ de Schistosoma mansoni que, em condições naturais, evoluem em B. glabrata de Belo Horizonte e B. tenagophila de São José dos Campos, respectivamente. Oitenta espécimens foram expostos à cepa BH dos quais em 13 ou 16,2% a infecção evoluiu caracteristicamente até a formação de esporocistos secundários sem haver, contudo, eliminação de cercárias, mesmo no indivíduo que apresentou uma sobrevivência de 88 dias após a exposição. Não se verificou cura espontânea neste lote. Entre as 40 B. straminea expostas à cepa SJ 9 ou 22,5% infectaram-se, sendo que apenas duas eliminaram poucas cercárias aos 57 e 77 dias após a exposição, por dois dias consecutivos, tendo uma morrido e uma se curado espontaneamente. A cura espontânea do parasitismo foi notado em mais dois indivíduos, nos quais a infecção foi observada através da concha. Cortes histológicos seriados de 9 caramujos, expostos individualmente a 50 miracídios da cepa BH e fixados entre 6 e 120 horas após a exposição, mostraram esporocistos em desenvolvimento e esporocistos invadidos por amebócitos, sem formação de granulomas por parte do hospedeiro, fato assinalado em caramujos suscetíveis. A população estudada comportou-se experimentalmente de modo semelhante a outras populações de B. straminea testadas em laboratório, isto é, com baixa suscetibilidade, embora tal comportamento não afaste a possibilidade dela vir a manter o ciclo do parasita em sua área de distribuição.In May 1973 one of the Authors (C.A.C. collected specimens of Biomphalaria straminea (Dunker 1848 at imacita, Bagua Province, Amazonas, Pem. This

  7. Primeira ocorrência de Biomphalaria straminea no Sul Goiano, Brasil First occurrence of Biomphalaria straminea in the South Goiano, Brazil

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    Carlos Henrique Marchiori

    1999-12-01

    Full Text Available Relata-se a primeira ocorrência do Biomphalaria straminea no Sul do Estado de Goiás, em ambiente natural. Trinta exemplares de Biomphalaria straminea foram coletados em janeiro de 1998, em Cachoeira Dourada de Goiás. Verificou-se que a falta de saneamento e de educação sanitária da população e a presença do caramujo são condições fundamentais para o estabelecimento de um foco de transmissão.The objective of this note is to report the occurrence of the Biomphalaria straminea in the county of Cachoeira Dourada in the south of Goiás, and with that enhance the knowledge about its geographical distribution in the state. More than identify the species, the collection of thirty samples helped study and verify the presence of cercariae, especially because they were found in a setting which offers proper conditions to the development of a focal transmission site of schistosomiasis.

  8. Susceptibility of Biomphalaria tenagophila and Biomphalaria straminea to Schistosoma mansoni infection detected by low stringency polymerase chain reaction

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    JANNOTTI-PASSOS Liana Konovaloff

    2000-01-01

    Full Text Available 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.

  9. Predicting the spatial distribution of Biomphalaria straminea, a potential intermediate host for Schistosoma mansoni, in China

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    Mohamed R. Habib

    2016-11-01

    Full Text Available Schistosomiasis is one of the most prevalent parasitic diseases impacting human health in the tropics and sub-tropics. The geographic distribution of Schistosoma mansoni, the most widespread species, includes areas in Africa, the Middle East, South America and the Caribbean. Snails of the genus Biomphalaria act as intermediate host for S. mansoni. Biomphalaria straminea is not indigenous in China but was accidentally introduced to Hong Kong from South America and has spread to other habitats in the southern parts of the country. This species is known for its great dispersal capacity that highlights the importance of the snail as a potential host for S. mansoni in China. In this connection, although no such infection has been recorded in the field so far, the continuous expansion of China’s projects in endemic areas of Africa and import of the infection via returning workers or visitors deserve attention. The purpose of this study was to map and predict the spatial distribution of B. straminea in China. Snail occurrence data were assembled and investigated using MaxEnt software, along with climatic and environmental variables to produce a predictive risk map. Of the environmental variables tested, the precipitation of warmest quarter was the most contribution factor for snail’s spatial distribution. Risk areas were found in southeastern China and it is expected that they will guide policies and control programmes to potential areas area of snail abundance and used for spatial targeting of control interventions for this invasive species.

  10. Nonhemocyte sources of selected lysosomal enzymes in Biomphalaria glabrata, B. tenagophila and B. straminea (Mollusca: Pulmonata

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    Gary E. Rodrick

    1981-09-01

    Full Text Available The specific activities of acid phosphatase, alkaline phosphatase, β-glucuronidase, lysozymes, glutamate-oxalacetate transaminase and glutamate-pyruvate transaminate were determined in the head-foot and digestive gland of Brazilian Biomphalaria glabrata (Touros, B. tenagophila (Caçapava and B. straminea (Monsenhor Gil. All six enzymes were detected inthe 3000g supernatant. Both cytoplasmic enzymes, glutamate-oxalacetate and glutamate-pyruvate transaminase exhibited the highest specific activities. In the case of the four hydrolytic enzymes assayed, β-glucuronidase exhibited the highest specific activity while lysozyme showed the lowest activity. All six enzymes are thought to be produced by cells within the head-foot and digestive gland of B. glabrata, B. tenagophila and B. straminea.Foram determinadas, na massa cefalopedal e na glândula digestiva de Biomphalaria glabrata de Touros (Rio Grande do Norte B. tenagophila de Cacapava (Sao Paulo e B. straminea de Monsenhor Gil (Piauí, as atividades específicas das seguintes enzimas: fosfatase acida, fosfatase alcalina, beta-glucuronidase, lisozima, transaminase glutâmico-oxalacetica e transaminase glutâmico-piruvica. As seis enzimas referidas foram detectadas no sobrenadante a 3000g. Ambas as enzimas citoplasmaticas - transaminases glutamico-oxalacetica e glutamico-piruvica - mostraram as atividades específicas mais altas. No caso das quatro enzimas hidrolíticas, a beta-glucuronidase revelou a mais alta atividade específica, enquanto a lisozima revelou a mais baixa. E admitido que todas as seis enzimas sao produzidas por celulas presentes na massa cefalopedal e na glândula digestiva das tres especies de moluscos examinadas.

  11. Estudo da potencialidade de populações de Biomphalaria straminea do Estado de Minas Gerais, como hospedeiras do Schistosoma mansoni Potentiality of the Biomphalaria straminea populations of the State of Minas Gerais, as hosts of Schistosoma mansoni

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    Cecília Pereira de Souza

    1983-09-01

    Full Text Available Caramujos de Biomphalaria straminea, descendentes de exemplares coletados em nove municípios do Estado de Minas Gerais, foram infectados experimentalmente com três cepas de Schistosoma mansoni: "LE", procedente de Belo Horizonte (MG; "SJ", procedente de São José dos Campos (SP e "AL" procedente do Nordeste (AL. As taxas de infeção variaram de 0,0 a 24,0% com a cepa "LE"; de 0,0 a 16% com a cepa "SJ" e de 2,0 a 9,0% com a cepa "AL". Os índices de infecção experimental obtidos foram semelhantes aos registrados por outros autores, para B. straminea dessa região. Comparou-se o número de cercárias de cepa "LE", eliminadas por oito exemplares de B. straminea de Baldim e oito Biomphalaria glabrata do controle, após 30 minutos de exposição à luz. O número de cercárias eliminadas por B. straminea foi de 4.550, aproximadamente cinco vezes menor que o de B. glabrata, 22.679. Discute-se a potencialidade desses moluscos como hospedeiros do S. mansoni nessa região.The decendents of Biomphalaria straminea snails collected in nine regions from the State of Minas Gerais were experimentally infected with three strains of Schistosoma mansoni: "LE", from Belo Horizonte, Minas Gerais; "SJ", from São José dos Campos, State of São Paulo and "AL", from State of Alagoas. The infection rates obtained were of 0 to 24% (LE strain, 0 to 16% (SJ strain and 2 to 9% (AL strain. These infection rates were similar to those obtained by other authors for B. straminea from this region. Comparation were made between the numbers of cercariae (LE strain shed by eight specimens of B. straminea from Baldim and eight B. glabrata of the control group, after 30 minutes of exposure to light. B. straminea shed 4,550 cercariae, about five times less than B. glabrata (22,679. The authors discuss the potentiality of theses molluscs as hosts of S. mansoni in this region.

  12. Suscetibilidade de biomphalaria glabrata, B. straminea e B. tenagophila a diferentes cepas de schistosoma mansoni

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    Luiz Candido de Souza Dias

    1987-08-01

    Full Text Available Em condições experimentais foi estudada a suscetibilidade de Biomphalaria glabrata, B. straminea e B. tenagophila a quatro linhagens humanas (MAP, PTH, UPH, e OuH e duas de roedores silvestres (PTR e VPR do Schistosoma mansoni. Grupos de 50 moluscos foram expostos individualmente a 10 miracídios e observados durante 70 dias. Avaliou-se a suscetibilidade dos moluscos ao parasito por meio da % de animais com esporocistos, % de moluscos que eliminavam cercárias e mortalidade conjunta dos animais expostos e infectados. Exemplares de B. glabrata mineira infectaram-se com cepa simpátrica (MAP e com 5 alopátricas do Estado de São Paulo (PTH, VPH, OuH, PTR e VPR. B. glabrata paulista mostrou altas taxas de infecção com as cepas MAP, VPR e OuH do trematódeo. Quatro % dos exemplares B. straminea de São Paulo eliminavam cercárias de cepas simpátricas; com cepa mineira apenas 4% apresentaram esporocistos na vigência de 20 miracídios por molusco; as menores taxas de mortalidade foram registradas com essa espécie de molusco, não sendo maior do que 20%. B. tenagophila paulista foi suscetível apenas às linhagens simpáticas sendo 6% a maior taxa de moluscos que eliminaram cercárias. Os resultados indicam que os movimentos populacionais humanos dentro do território paulista e para fora dele são importantes na disseminação da esquistossomose mansônica.

  13. Susceptibility of Argentinean Biomphalaria tenagophila and Biomphalaria straminea to infection by Schistosoma mansoni and the possibility of geographic expansion of mansoni schistosomiasis

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    Luciana Franceschi Simoes

    2013-10-01

    Full Text Available Introduction Human migration and the presence of natural vectors (mollusks of Schistosoma mansoni are the primary causes of the expansion of mansoni schistosomiasis into southern areas of South America. Water conditions are favorable for the expansion of this disease because of the extensive hydrographic network, which includes the basins of the Paraná and Uruguay rivers and favors mollusk reproduction. These rivers also aid agriculture and tourism in the area. Despite these favorable conditions, natural infection by S. mansoni has not yet been reported in Argentina, Uruguay, or Paraguay. Methods Two species of planorbid from Argentina, Biomphalaria straminea and B. tenagophila, were exposed to the miracidia of five Brazilian strains of S. mansoni. Results Biomphalaria tenagophila (Atalaya, Buenos Aires province was infected with the SJS strain (infection rate 3.3%, confirming the experimental susceptibility of this Argentinian species. Biomphalaria straminea (Rio Santa Lucía, Corrientes province was susceptible to two Brazilian strains: SJS (infection rate 6.7% and Sergipe (infection rate 6.7%. Conclusions These results demonstrate that species from Argentina have the potential to be natural hosts of S. mansoni and that the appearance of foci of mansoni schistosomiasis in Argentina is possible.

  14. First report on the presence of Biomphalaria straminea in the municipality of Jaboticatubas, State of Minas Gerais, Brazil.

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    Massara, Cristiano Lara; Carvalho, Omar dos Santos; Caldeira, Roberta Lima; Jannotti-Passos, Liana Konovaloff; Schall, Virgínia Torres

    2002-01-01

    This is the first report on occurrence of Biomphalaria straminea in the district of São 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.

  15. First report on the presence of Biomphalaria straminea in the municipality of Jaboticatubas, State of Minas Gerais, Brazil

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    Cristiano Lara Massara

    2002-10-01

    Full Text Available This is the first report on occurrence of Biomphalaria straminea in the district of São 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.

  16. Study of the snail intermediate hosts for Schistosoma mansoni on Itamaracá Island in northeast Brazil: spatial displacement of Biomphalaria glabrata by Biomphalaria straminea

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    Constança S. Barbosa

    2014-05-01

    Full Text Available In 2012 a malacological survey of the breeding sites of Biomphalaria glabrata and B. straminea, the two intermediate host snails of Schistosoma mansoni, was carried out on Itamaraca Island in Pernambuco, Brazil. This study has now been extended by studying the competition between the two species. Snails were collected and dissected to identify the species and tests were performed to verify S. mansoni infection. Student’s t test was used to compare the proportion between the two species and their breeding sites and a parasitological survey was conducted among local residents, using the Kato-Katz method. The spatial distribution of the two snail species was determined using TerraView, while a snail density map was constructed by Kernel estimate. The survey identified two breeding sites for B. glabrata with 17 specimens and 19 breeding sites for B. straminea with 459 snails, all of them negative for S. mansoni infection. The statistical analysis revealed that the proportion of the numbers of specimens and breeding sites of B. straminea (37.84 ± 9.01 were significantly greater than those of B. glabrata (8.50 ± 6.50. Parasitological examinations from 41 residents diagnosed two cases of schistosomiasis with parasite loads of 60 and 84 eggs per 1 g of stool, respectively. This indiction of a competitive process between the two snail species requires monitoring of schistosomiasis in the resident and travelling human populations occupying this environment, which could potentially result in social and economic changes on the island risking its attraction as a centre for eco-tourism.

  17. Ocorrência de Biomphalaria straminea (Pulmonata: Planorbidae na estação de aqüicultura do IBAMA em Uberlândia, MG

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    Elisângela de Paula Silveira

    1997-10-01

    Full Text Available Este trabalho avalia a ocorrência de moluscos planorbídeos na estação de psicultura do IBAMA em Uberlândia, Minas Gerais. Constatou-se a presença de Biomphalaria straminea em 39,5% dos tanques de criação. Nenhum dos caramujos estava infectado por Schistosoma mansoni, mas investigações complementares devem ser realizadas na área.This work evaluates the occurrence of freshwater snails in the IBAMA's fish breeding station in Uberlandia, Minas Gerais State. We verified the presence of Biomphalaria straminea in 39.5% of all breeding tanks. None of the snails were infected by Schistosoma mansoni, but futher investigation should be done in the area.

  18. Biomphalaria straminea (Mollusca: Planorbidae) as an intermediate host of Drepanocephalus spp. (Trematoda: Echinostomatidae) in Brazil: a morphological and molecular study.

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    Pinto, Hudson A; Griffin, Matt J; Quiniou, Sylvie M; Ware, Cynthia; Melo, Alan L

    2016-01-01

    Species of trematodes belonging to the genus Drepanocephalus are intestinal parasites of piscivorous birds, primarily cormorants (Phalachrocorax spp.), and are widely reported in the Americas. During a 4-year malacological study conducted on an urban lake in Brazil, 27-collar-spined echinostome cercariae were found in 1665/15,459 (10.7 %) specimens of Biomphalaria straminea collected. The cercariae were identified as Drepanocephalus spp. by sequencing the 18S (SSU) rDNA, ITS1/5.8S rDNA/ITS2 (ITS), 28S (LSU) rDNA region, cytochrome oxidase subunit 1 (CO1), and nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1) markers. In experimental life cycle studies, metacercariae developed in laboratory-reared guppies (Poecilia reticulata); however, attempts to infect birds and rodents were unsuccessful. Two closely related morphotypes of cercariae were characterized. One species, identified by molecular markers as a genetic variant of Drepanocephalus auritus (99.9 % similarity at SSU, ITS, LSU; 97.2 % at CO1; 95.8 % at ND1), differs slightly from an archived North American isolate of this species also sequenced as part of this study. A second species, putatively identified as Drepanocephalus sp., has smaller cercariae and demonstrates significant differences from D. auritus at the CO1 (11.0 %) and ND1 (13.6 %) markers. Aspects related to the morphological taxonomic identification of 27-collar-spined echinostome metacercariae are briefly discussed. This is the first report of the involvement of molluscs of the genus Biomphalaria in the transmission of Drepanocephalus and the first report of D. auritus in South America.

  19. [The occurrence of Biomphalaria straminea (Pulmonata: Planorbidae) on an aquaculture farm of IBAMA in Uberlândia, MG. Instituto Brasileiro do Meio Ambiente a dos Recursos Naturais Renováveis].

    Science.gov (United States)

    Silveira, E de P; Marçal Júnior, O; Machado, M I

    1997-01-01

    This work evaluates the occurrence of freshwater snails in the IBAMA's fish breeding station in Uberlândia, Minas Gerais State. We verified the presence of Biomphalaria straminea in 39.5% of all breeding tanks. None of the snails were infected by Schistosoma mansoni, but further investigation should be done in the area.

  20. Atração miraxonal exercida por Biomphalaria straminea, Lymnaea columella e Physa sp, sobre miracídios de Schistosoma mansoni da linhagem BH The miraxonal attraction exercised by Biomphalaria straminea, Lymnaea columella and Physa sp over miracidia of Schistosoma mansoni

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    Luiz A. Magalhães

    1991-02-01

    Full Text Available Utilizando-se um artefato de vidro composto de duas câmaras unidas por um canal, testamos a atração miraxonal exercida por Biomphalaria straminea, Lymnaea columella e Physa sp, sobre larvas de Schistosoma mansoni da linhagem BH. Os moluscos, ou suas águas de condicionamento (SCW, foram colocados aleatoriamente em uma das câmaras, contendo o restante do artefato somente água declorada. Dez miracídios foram depositados no centro do canal. O comportamento dos miracídios foi observado por 15 min. Foram feitas dez replicações de cada experimento, utilizando-se espécimens de moluscos e miracídios diferentes. Verificou-se que todos os moluscos e suas SCW exerceram atração miraxonal, sendo que Physa sp atraiu mais que Lymnaea columella. Foi isolado um único exemplar de B. straminea que exerceu efeito repulsivo sobre os miracídios de S. mansoni.The attraction exercised over Schistosoma mansoni miracidia by Biomphalaria straminea, Lymnaea columella and Physa sp using a specially designed apparatus consisting of two circular glass chambers joined by an open channel were studied. The molluscs or their snail-conditioned water (SCW was placed in one of the chambers (randomly chosen. In the channel ten miracidia was deposited and the count of miracidia in each of the three compartments (the two chambers and the channel was recorded during fifteen minutes. Ten replications of each experiment with different specimens of molluscs and miracidia were made. Statistical and ad-hoc exploratory data analysis showed that: a the three species of molluscs and their SCW attract the miracidia; b Physa sp attract more miracidia then L. columella. There was an isolated single B. straminea specimen that had a repulsive effect to the miracidia.

  1. Biomphalaria kuhniana (Clessin, 1883, planorbid mollusc from South America Biomphalaria kuhniana (Clessin, 1883, molusco planorbídeo da América do Sul

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    W. Lobato Paraense

    1988-03-01

    Full Text Available The validity of Biomphalaria kuhniana (Clessin, 1883 is confirmed through morphological study of specimens from Surinam (type locality and the area of Tucurui (Tocantins river, state of Pará, Brazil in comparison with B. straminea (Dunker, 1848, and throught crossing experiments which revealed complete reproductive isolation between the two species. The full-grown shell of kuhniana is smaller (about 7.5 mm than that of straminea (11 mm to 16.5 mm. Anatomically they differ in the degree of corrugation of the vaginal wall (little developed in kuhniana, conspicuous in straminea, number and shape of prostatic diverticula (kuhniana 4 to 9, shorter and less branched; straminea 9 to 18, longer and more branched,number of muscle layers at the middle of the penis (two in kuhniana, three in straminea, distal segment of the spermiduct usually straight or slightly wavy in kuhniana, more or less curly in straminea. Differences between B. kuhniana and B. intermedia (paraense & Deslandes, 1962 are less marked. The latter has a shell up to about 12 mm in diameter, 7 to 15 prostatic diverticula, two muscle layers at the middle of the penis, and a vaginal wall with a combination of a more or less developed corrugation (or sometimes a mere swelling on the left of the spermathecal duct and a rudimentary pouch on the right of the duct. A Biomphalaria straminea complex is proposed to include that species as well as B. kuhniana and B. intermedia.A validade de Biomphalaria Kuhniana (Clessin, 1883 é confirmada pelo estudo morfológico de espécimes do Suriname (localidade tipo e da área de Tucuruí (rio Tocantins, Estado do Pará, Brasil, em comparação com B. straminea (Dunker, 1848, e por experiências de cruzamento que revelaram completo isolamento reprodutivo entre as duas espécies. A concha adulta de Kuhniana é menor (cerca de 7,5 mm que a de straminea (11 mm a 16.5 mm. As duas espécies distinguem-se anatomicamente pelo grau de enrugamento da parede vaginal

  2. Dispersão de Biomphalaria straminea, hospedeira intermediária do Schistosoma mansoni, através da distribuição de peixes The spreading of Biomphalaria straminea, intermediate host of Schistosoma mansoni through the distribution of fishes

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    Renato de R. Corrêa

    1970-12-01

    Full Text Available Foi focalizado, pela primeira vez o encontro de B. straminea no Estado de São Paulo. Esta espécie vem juntar-se aos planorbídeos já assinalados em nosso Estado. Foram descritos os criadouros, onde a B. straminea foi coletada, localizados em tanques de criação de peixes nas Estações de Piscicultura de Barra Bonita e Americana, Estado de São Paulo, e em um aquário particular na capital dêsse Estado. Fêz-se referência ao transporte de peixes oriundos de zonas do país onde ocorre aquela espécie, Amazonas e Ceará, como responsável pela introdução daquele molusco no Estado. Destacou-se êsse achado pelo perigo que representa a distribuição de peixes da maneira como vem sendo feita atualmente em nosso país, tendo sido julgado necessário o estabelecimento de quarentena para aquêles vindos de zonas infestadas por espécies hospedeiras intermediárias do S. mansoni. Foram relatadas as medidas de combate aos caramujos efetuadas imediatamente após aquela descoberta e os resultados obtidos. Conclui-se que a dispersão passiva da B. straminea pelo transporte de peixes, deve ampliar a distribuição geográfica dêsse planorbídeo, já assinalado na Venezuela, Guianas e no Brasil, sendo que neste último ocorre em tôdas as Unidades Federativas, exceto, no Rio Grande do Sul, Santa Catarina, Rio de Janeiro e Territórios.Up the present, the works of collecting planorbids done in 226 municipalities for the elaboration of the geographical distribution chart in the State of São Paulo (Brazil, showed the presence of two intermediate host species of Schistosoma mansoni: Biomphalaria tenagophila and Biompralaria glabrata. Although the technicians from the Psiculture Stations, have not found snails in the water inside the containers used for the transportation of fishes, the ecological conditions of B. straminea in the latest researches are such as to indicate that they have been introduced, in our State through fish transportation imported

  3. 藁杆双脐螺在中国内陆的分布现状与传病风险%Distribution and schistosomiasis transmission risks of Biomphalaria stra-minea in inland China

    Institute of Scientific and Technical Information of China (English)

    黄少玉; 张启明; 李晓恒; 邓卓晖

    2014-01-01

    藁杆双脐螺可作为曼氏血吸虫中间宿主,1981年证实在深圳市局部地区有该螺孳生;2013年再次调查发现,该螺已在深圳市、以及周边的东莞市和惠州市等地大范围蔓延扩散,并已在当地形成较优势种群,有进一步扩散的趋势。由于深圳市及周边地区与国际交流密切,劳务输出等人口流动性大,且目前我国由境外输入的曼氏血吸虫病病例报道亦逐渐增多,因此曼氏血吸虫病在我国传播或流行的潜在风险因素正在逐步增加,必须引起高度重视,及早采取相应的防控措施,加强监测,降低该病在我国传播或流行的风险。本文就藁杆双脐螺在中国内陆的发现、分布、扩散蔓延及传病风险等进行了综述,并提出相关的防控建议。%Biomphalaria straminea,the intermediary host of Schistosoma mansoni,was found by survey in local areas of Shen-zhen City in 1981,which was the first finding of the snail in inland China. By 2013,the snail had spread in large range of Shen-zhen City and overspread to the surrounding regions,Dongguan City and Huizhou City. Due to the facts that Shenzhen City has many international communications and is a key area of labor export,with high population mobility,while the reports of S. manso-ni infection in the returnees of our country from Africa have been increasing recently,it must be paid a high attention to whether the epidemic or transmission of schistosomiasis mansoni may happen under the present circumstance. This paper initially discusses the finding,distribution,spreading and overspreading and transmission risk of B. straminea in inland China and puts forward some related control suggestions.

  4. Morphological and polymerase chain reaction-restriction fragment lenght polymorphism characterization of Biomphalaria kuhniana and Biomphalaria amazonica from Colombia

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    Luz E Velásquez

    2002-10-01

    Full Text Available In Colombia, five Biomphalaria planorbid species are known: B. kuhniana, B. straminea, B. peregrina, B. canonica and B. oligoza(var. B. philippiana. Among them, B. straminea is intermediate host of Schistosoma mansoni and B. peregrina has been found to be experimentally susceptible to this parasite. B. straminea is commonly confused with B. kuhniana and they have been clustered together with B. intermedia in the complex named B. straminea. The difficulties involved in the specific identification, based on morphological data, have motivated the use of new techniques as auxiliary tools in cases of inconclusive morphological identification of such planorbid. In the present study, five Biomphalaria populations from the Colombian Amazon region and from Interandian Valleys were morphologically identified and characterized by polymerase chain reaction-restriction fragment lenght polymorphism directed at the internal transcribed spacer region of the rRNA gene, followed by digestion of the generated fragment with restriction enzymes (DdeI, AluI, RsaI, MvaI and HaeIII. Known profiles of the Brazilian species B. straminea, B. peregrina, B. kuhniana, B. intermedia and B. amazonica, besides B. kuhniana from Colombia, were used for comparison. The five populations under study were morphologically and molecularly identified as B. kuhniana and B. amazonica.

  5. Biomphalaria glabrata no Estado do Piauí Biomphalaria glabrata in the State of Piaui

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    W. Lobato Paraense

    1984-09-01

    Full Text Available É registrado o primeiro encontro do molusco planorbideo Biomphalaria glabrata, hospedeiro intermediário do Schistosoma mansoni, no Estado do Piauí, coletado em vários criadouros na cidade de Parnaíba. O exame de 694 exemplares revelou a presença de formas evolutivas de algumas espécies de trematodeos, mas não de Schistosomatidea. Nenhum caso autoctone de xistosomose foi até agora identificado na população humana da cidade. A presença da B. glabrata em Parnaíba amplia em 20 km para leste a área de sua distribuição na Região Litoral Norte da Grande Região Nordeste do Brasil onde era conhecida até em Avaioses no extremo leste da parte maranhense da referida Região. Outros moluscos também coletados nos mesmos criadouros foram Biomphalaria straminea, Drepanotrema lucidum. D. cimex, D. depressissimum, Physidae e Ampullarriidae.The occurrence of Biomphalaria glabrata is recorded for the first time in the state of Piauí, where it was collected from several breeding places in the city of Parnaíba. Examination of 694 specimens showed that a part of them were infected with trematodes other than Schistosomatidae. So far no autochthonous cases of schistosomiasis have been identified in the city. The presence of B. glabrata in Parnaíba extends by 20 Km eastward its range on the Northern Coastal region of the Great Northeastern region of Brazil, where it had been found as far as Araioses, on the eastern extreme of the state of Maranhão. Other snail species collected from the same breeding places were Biomphalaria straminea, Drepanotrema lucidum, D. cimex, D. depressissimum, Physidae and Ampullariidae.

  6. Bioactivities of Chuquiraga straminea sandwith.

    Science.gov (United States)

    Mendiondo, María Elena; Juáreza, Berta E; Zampini, Catiana; Isla, Maria Inés; Ordoñez, Roxana

    2011-07-01

    Methanolic extracts of Chuquiraga straminea Sandwith, subfamily Barnadesioideae (Asteraceae) showed the presence of quercetin-3-O-glucoside, quercetin-3-O-rutinoside, kaempferol, kaempferol-3-O-glucoside and kaempferol-3-O-rutinoside. Antioxidant and antimicrobial activity was determined. The total extracts showed antioxidant activity by DPPH and ABTS method (SC50 14.5 to 34.9 microg/mL). A significantly positive correlation was observed between the antioxidant activity and the total phenolics (R2 > 0.93). The extracts were active against ten methicillin resistant and sensitive Staphylococcus aureus strains isolated from nosocomial infection (MIC values between 200 to 800 microg/mL). These preliminary studies are highly interesting as they open new ways for further applications in the treatment of infections by methicillin resistant S. aureus.

  7. The distribution of Biomphalaria spp. in different habitats in relation to physical, biological, water contact and cognitive factors in a rural area in Minas Gerais, Brazil

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    Kloos Helmut

    2001-01-01

    Full Text Available A total of 256 sites in 11 habitats were surveyed for Biomphalaria in Melquiades rural area (State of Minas Gerais in August and November 1999 and in March 2000. Of the 1,780 Biomphalaria collected, 1,721 (96.7% were B. glabrata and 59 (3.3% B. straminea. Snails were found in all habitats except in wells, with the largest mean numbers in tanks, seepage ponds and canals, and the smallest numbers in springs, rice fields and fishponds. People's knowledge of the occurrence of Biomphalaria at the collection sites and the presence of Biomphalaria ova were strongly correlated with the occurrence of snails, and distance between houses and collection sites, as well as water velocity were inversely correlated with Biomphalaria occurrence (p < 0.001. The strongest predictor o f Biomphalaria occurrence was the presence of tilapia fish in fishponds. Fourteen Biomphalaria (0.8% of all snails found at 6 sites were infected with Schistosoma mansoni. Suggestions are made for the utilization of local people's knowledge in snail surveys and further studies are recommended on the possible use of tilapia for biological control of Biomphalaria in fishponds, as well as modeling of S. mansoni transmission and reinfection.

  8. Spatial distribution of Biomphalaria spp., the intermediate host snails of Schistosoma mansoni, in Brazil.

    Science.gov (United States)

    Scholte, Ronaldo G C; Carvalho, Omar S; Malone, John B; Utzinger, Jürg; Vounatsou, Penelope

    2012-09-01

    Schistosomiasis mansoni remains an important parasitic disease of man, endemic in large parts of sub-Saharan Africa, the Middle East, South America and the Caribbean. The aetiological agent is the trematode Schistosoma mansoni, whereas aquatic snails of the genus Biomphalaria act as intermediate hosts in the parasite life cycle. In Brazil, the distribution of Biomphalaria spp. is closely associated with the occurrence of schistosomiasis. The purpose of this study was to map and predict the spatial distribution of the intermediate host snails of S. mansoni across Brazil. We assembled snail "presenceonly" data and used a maximum entropy approach, along with climatic and environmental variables to produce predictive risk maps. We identified a series of risk factors that govern the distribution of Biomphalaria snails. We find that high-risk areas for B. glabrata are concentrated in the regions of Northeast and Southeast and the northern part of the South region. B. straminea are found in the Northeast and Southeast regions, and B. tenagophila are concentrated in the Southeast and South regions. Our findings confirm that the presence of the intermediate host snails is correlated with the occurrence of schistosomiasis mansoni. The generated risk maps of intermediate host snails might assist the national control programme for spatial targeting of control interventions and to ultimately move towards schistosomiasis elimination in Brazil.

  9. Production of Aneuploid Pinctada martensii Dunker in Tetraploid Induction

    Institute of Scientific and Technical Information of China (English)

    何毛贤; 林岳光; 沈琪; 胡建兴; 姜卫国

    2001-01-01

    Aneuploidy embryos of Pinctada martensii Dunker are produced during tetraploid induction by inhibiting the first polar body in eggs from triploid fertilized with haploid sperms with cytochalasin B treatment. Chromosome analysis reveals that there are 88.18 ±6.79% aneuploidy embryos, and 28.70% aneuploids in pearl oysters of one-year age These aneuploids have five chromosomal conditions, such as 2n + 1(29), 2n + 2 (30), 3n-2 (40), 3n-1(41) and 3n + 1 (43). Results of growth measurement show that there is no significant difference between aneuploids (as a group) and diploids in body size and weight (p > 0.10), but the aneuploide is obviously different from triploid (p < 0.01). The mean body size and weight of aneuploids in diploid condition (2n ± 1 and 2n ± 2) are significantly smaller than those of diploids (p < 0.01),but aneuploids within triploid condition (3n ± 1 and 3n ± 2) are not smaller than diploids in body size and weight (p > 0.1).This study indicates Pinctada martensii Dunker could tolerate aneuploidy by 7 ~ 14% of the haploid genome, and that aneuploids of this species are viable under certain conditions.

  10. Malacological survey of Biomphalaria snails in municipalities along the Estrada Real in the southeast of the State of Minas Gerais, Brazil

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    Sandra Helena Cerrato Tibiriçá

    2011-04-01

    Full Text Available INTRODUCTION: The increasing practice of ecotourism and rural tourism in the State of Minas Gerais, Brazil, highlights the importance of studies concerning the occurrence of potential intermediate hosts of Schistosoma mansoni. This study aimed to identify species of Biomphalaria snails in municipalities along the Estrada Real, an important Brazilian tourism project. METHODS: The specimens were collected in different water collections of 36 municipalities along the Estrada Real in the southeast of the State of Minas Gerais. Biomphalaria species were characterized using both morphological and molecular approaches. The research was conducted between August 2005 and September 2009 and all the sites visited were georeferenced using GPS. RESULTS: Six Biomphalaria species were found in 30 of the 36 municipalities studied: glabrata, tenagophila, straminea, peregrina, occidentalis and schrammi. The first three species of Biomphalaria, recognized as intermediate hosts of S. mansoni, were present in 33.3%, 47.2% and 8.3% of the municipalities studied, respectively. The mollusks were found in different types of water collections and no infection by S. mansoni was detected. The highest occurrence of Biomphalaria concentration was verified in the area covered by the Caminho Novo route (Diamantina/MG to Rio de Janeiro/RJ. CONCLUSIONS: Considering the occurrence of schistosomiasis in the State of Minas Gerais and the socioeconomic repercussions involved in the Estrada Real Project, this work focuses on the vulnerability of water collections due to the presence of Biomphalaria mollusks and emphasizes the need for epidemiological surveillance and sanitary and educational measures integrated with the local community and tourism sectors.

  11. Ivermectin efficacy against Biomphalaria, intermediate host snail vectors of Schistosomiasis.

    Science.gov (United States)

    Katz, Naftale; Araújo, Neusa; Coelho, Paulo Marcos Zech; Morel, Carlos Medicis; Linde-Arias, Ana Rosa; Yamada, Takeshi; Horimatsu, Yuki; Suzuki, Koh; Sunazuka, Toshiaki; Ōmura, Satoshi

    2017-03-15

    The impact of ivermectin on adult snails of the genus Biomphalaria (B. glabrata, B. tenagophila and B. straminea), B. glabrata infected with Schistosoma mansoni, snail egg-masses cercariae and miracidia, as well as on guppy fish (Poecilia reticulata) was examined and evaluated. Biomphalaria snails, egg-masses, parasite stages and guppies were all exposed to different concentrations of ivermectin for 24 h, followed by regular observations of mortality. The calculated lethal doses of ivermectin were around an LD50 of 0.03 μg ml(-1), and an LD90 of 0.3 μg ml(-1) for the three species of snails. Specimens of B. glabrata actually shedding parasite cercariae all died when exposed to ivermectin at a concentration of a mere 0.01 μg ml(-1). Ivermectin B1a, the major (80%) component of commercially available ivermectin, proved to be inactive, and it was the minor (20%) component, ivermectin B1b, which caused snail death. Snail egg-masses were not affected, even at the highest concentration of 100 μg ml(-1). With respect to S. mansoni parasite stages, 0.2 μg ml(-1) ivermectin killed 50% of cercariae and miracidia within five minutes, rising to 90% after 30 min. Mortality of guppy fish within 24 h of exposure to ivermectin at concentrations of 0.5 μg ml(-1) and 0.01 μg ml(-1), were 100% and 30%, respectively. The concentration of 0.01 μg ml(-1) that killed Schistosoma mansoni-infected snails only caused 30% mortality in guppy fish. Ivermectin can be considered a promising molluscicide, especially as it is more potent against infected snails than uninfected ones, although it has no impact on egg-masses. Ivermectin and its derivatives could be explored in the search for a new agent to help control schistosomiasis transmission.The Journal of Antibiotics advance online publication, 15 March 2017; doi:10.1038/ja.2017.31.

  12. Characterization of South American Snails of the Genus Biomphalaria (Basommatophora: Planorbidae) and Schistosoma mansoni (Platyhelminthes: Trematoda) in Molluscs by PCR-RFLP

    Science.gov (United States)

    Teodoro, Tatiana Maria; Jannotti-Passos, Liana Konovaloff; Lira-Moreira, Pollanah M.; Goveia, Christiane De Oliveira; Carvalho, Omar dos Santos

    2016-01-01

    The identification of snails of the genus Biomphalaria can be done using morphological characteristics which depends on the size of the snails and skill and knowledge of researcher. These methods sometimes are not adequate for identification of species. The PCR-RFLP, using the ITS region of the rDNA, has been used to identify Brazilian species of the genus Biomphalaria. Nevertheless, there is a lack of information about snails from other Latin American countries. In addition, some snails may be infected by Schistosoma mansoni and when submitted to PCR-RFLP they show molecular profiles different from those previously standardized for the other mollusc species. In this work the molecular profiles of 15 species and the subspecies were established by PCR-RFLP of ITS-rDNA with the enzyme DdeI. Moreover, the molecular profiles of host species, B. glabrata, B. straminea, B. tenagophila, and B. prona, infected by S. mansoni were also established. The molluscs were dissected to permit morphological identification. These results contribute to a correct identification of snails of the genus Biomphalaria and detection of these snails infected by S. mansoni. PMID:27981045

  13. Characterization of South American Snails of the Genus Biomphalaria (Basommatophora: Planorbidae and Schistosoma mansoni (Platyhelminthes: Trematoda in Molluscs by PCR-RFLP

    Directory of Open Access Journals (Sweden)

    Roberta Lima Caldeira

    2016-01-01

    Full Text Available The identification of snails of the genus Biomphalaria can be done using morphological characteristics which depends on the size of the snails and skill and knowledge of researcher. These methods sometimes are not adequate for identification of species. The PCR-RFLP, using the ITS region of the rDNA, has been used to identify Brazilian species of the genus Biomphalaria. Nevertheless, there is a lack of information about snails from other Latin American countries. In addition, some snails may be infected by Schistosoma mansoni and when submitted to PCR-RFLP they show molecular profiles different from those previously standardized for the other mollusc species. In this work the molecular profiles of 15 species and the subspecies were established by PCR-RFLP of ITS-rDNA with the enzyme DdeI. Moreover, the molecular profiles of host species, B. glabrata, B. straminea, B. tenagophila, and B. prona, infected by S. mansoni were also established. The molluscs were dissected to permit morphological identification. These results contribute to a correct identification of snails of the genus Biomphalaria and detection of these snails infected by S. mansoni.

  14. Malacological survey of Biomphalaria snails in municipalities along the Estrada Real in the southeast of the State of Minas Gerais, Brazil Pesquisa malacológica de Biomphalaria em municípios da Estrada Real, situados no sudeste do Estado de Minas Gerais

    Directory of Open Access Journals (Sweden)

    Sandra Helena Cerrato Tibiriçá

    2011-04-01

    Full Text Available INTRODUCTION: The increasing practice of ecotourism and rural tourism in the State of Minas Gerais, Brazil, highlights the importance of studies concerning the occurrence of potential intermediate hosts of Schistosoma mansoni. This study aimed to identify species of Biomphalaria snails in municipalities along the Estrada Real, an important Brazilian tourism project. METHODS: The specimens were collected in different water collections of 36 municipalities along the Estrada Real in the southeast of the State of Minas Gerais. Biomphalaria species were characterized using both morphological and molecular approaches. The research was conducted between August 2005 and September 2009 and all the sites visited were georeferenced using GPS. RESULTS: Six Biomphalaria species were found in 30 of the 36 municipalities studied: glabrata, tenagophila, straminea, peregrina, occidentalis and schrammi. The first three species of Biomphalaria, recognized as intermediate hosts of S. mansoni, were present in 33.3%, 47.2% and 8.3% of the municipalities studied, respectively. The mollusks were found in different types of water collections and no infection by S. mansoni was detected. The highest occurrence of Biomphalaria concentration was verified in the area covered by the Caminho Novo route (Diamantina/MG to Rio de Janeiro/RJ. CONCLUSIONS: Considering the occurrence of schistosomiasis in the State of Minas Gerais and the socioeconomic repercussions involved in the Estrada Real Project, this work focuses on the vulnerability of water collections due to the presence of Biomphalaria mollusks and emphasizes the need for epidemiological surveillance and sanitary and educational measures integrated with the local community and tourism sectors.INTRODUÇÃO: O aumento das práticas de ecoturismo e turismo rural, em Minas Gerais, Brasil, evidencia a importância de se realizarem estudos sobre a ocorrência de hospedeiros intermediários do Schistosoma mansoni, no estado. O

  15. Plant regeneration from protoplasts of Gentiana straminea Maxim

    Directory of Open Access Journals (Sweden)

    Shi Guomin

    2016-04-01

    Full Text Available A protocol is described for plant regeneration from protoplasts of Gentiana straminea Maxim. via somatic embryogenesis. Protoplasts were isolated from embryogenic calli in an enzyme solution composed of 2% Cellulase Onozuka R-10, 0.5% Macerozyme R-10, 0.5% Hemicellulase, and 0.5 M sorbitol with a yield of 3.0 × 106 protoplasts per gram of fresh weight. Liquid, solid-liquid double layer (sLD and agar-pool (aPL culture systems were used for protoplast culture. The aPL culture was the only method that produced embryogenic, regenerative calli. With aPL culture, the highest frequencies of protoplast cell division and colony formation were 39.6% and 16.9%, respectively, on MS medium supplemented with 2 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D and 0.5 mg/L N6-benzylaminopurine (BA. Microcalli were transferred to solid MS medium containing a reduced concentration of 2,4-D (0.5 mg/L to promote the formation of embryogenic calli. Somatic embryos developed into plantlets on MS medium supplemented with 2 mg/L BA at a rate of 43.7%.

  16. Biomphalaria species distribution and its effect on human Schistosoma mansoni infection in an irrigated area used for rice cultivation in northeast Brazil

    Directory of Open Access Journals (Sweden)

    Delmany Moitinho Barboza

    2012-09-01

    Full Text Available The role of irrigated areas for the spread of schistosomiasis is of worldwide concern. The aim of the present study was to investigate the spatial distribution of the intermediate snail host Biomphalaria in an area highly endemic for schistosomiasis due to Schistosoma mansoni, evaluating the relationship between irrigation and types of natural water sources on one hand, and the influence of place and time of water exposure on the intensity of human infection on the other. A geographical information system (GIS was used to map the distribution of the intermediate snail hosts in Ilha das Flores, Sergipe, Brazil, combined with a clinical/epidemiological survey. We observed a direct correlation between the intensity of human infection with S. mansoni and irrigation projects. Malacological studies to identify snail species and infection rates showed that B. glabrata is the main species responsible for human schistosomiasis in the municipality, but that B. straminea also plays a role. Our results provide evidence for a competitive selection between the two snail species in rice fields with a predominance of B. glabrata in irrigation systems and B. straminea in natural water sources.

  17. Confirmation of natural hybrids between Gentiana straminea and G. siphonantha (Gentianaceae) based on molecular evidence

    Institute of Scientific and Technical Information of China (English)

    Xiaojuan LI; Liuyang WANG; Huiling YANG; Jianquan LIU

    2008-01-01

    A few individuals with intermediate morpho-logy always appeared in the sympatric distributions of Gentiana straminea and G. siphonantha. These intermedi-ate individuals were hypothesized to be the hybrids of two species after a careful evaluation of their morphological characteristics. To test this hypothesis, sequence compar-ison of the internal transcribed spacer (ITS) regions of the nuclear ribosomal and trnS (GCU)-trnG (UCC) inter-genic spacer region of the chloroplast DNA from Gentiana straminea, G. siphonantha and the putative hybrids was performed. The results suggest that most intermediate individuals were the natural hybrids between G. straminea and G. siphonantha. In addition, we exam-ined the sequence variation among the individuals of both parent species and analyzed the possibility leading to the incongruent identification in some individuals based on morphologic and molecular evidences, respectively. The intraspecific diversification of DNA fragments within both parent species and their high variability in hybrid swarms probably resulted from chloroplast genome recombination and incomplete lineage sorting during the early stages of speciation origin of the parent species.

  18. Breeding of Biomphalaria tenagophila in mass scale

    Directory of Open Access Journals (Sweden)

    Florence Mara Rosa

    2013-02-01

    Full Text Available An efficient method for breeding Biomphalaria tenagophila (Taim lineage/RS was developed over a 5-year-period (2005-2010. Special facilities were provided which consisted of four cement tanks (9.4 x 0.6 x 0.22 m, with their bottom covered with a layer of sterilized red earth and calcium carbonate. Standard measures were adopted, as follows: each tank should contain an average of 3000 specimens, and would be provided with a daily ration of 35,000 mg complemented with lettuce. A green-house effect heating system was developed which constituted of movable dark canvas covers, which allowed the temperature to be controlled between 20 - 24 ºC. This system was essential, especially during the coldest months of the year. Approximately 27,000 specimens with a diameter of 12 mm or more were produced during a 14-month-period. The mortality rates of the newly-hatched and adult snails were 77% and 37%, respectively. The follow-up of the development system related to 310 specimens of B. tenagophila demonstrated that 70-day-old snails reached an average of 17.0 ± 0.9 mm diameter. The mortality rates and the development performance of B. tenagophila snails can be considered as highly satisfactory, when compared with other results in literature related to works carried out with different species of the genus Biomphalaria, under controlled laboratory conditions.

  19. Hybridism between Biomphalaria cousini and Biomphalaria amazonica and its susceptibility to Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Tatiana Maria Teodoro

    2011-11-01

    Full Text Available 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.

  20. Biomphalaria alexandrina in Egypt: Past, present and future

    Indian Academy of Sciences (India)

    Iman F Abou-El-Naga

    2013-09-01

    The African species of Biomphalaria appeared as a result of the relatively recent west-to-east trans-Atlantic dispersal of the Biomphalaria glabrata-like taxon. In Egypt, Biomphalaria alexandrina is the intermediate host for Schistosoma mansoni. Biomphalaria alexandrina originated in the area between Alexandria and Rosetta and has historically been confined to the Nile Delta. Schistosoma mansoni reached Egypt via infected slaves and baboons from the Land of Punt through migrations that occurred as early as the Vth Dynasty. The suggestion of the presence of Schistosoma mansoni infection in Lower Egypt during Pharaonic times is discussed despite the fact that that there is no evidence of such infection in Egyptian mummies. It is only recently that Biomphalaria alexandrina colonized the Egyptian Nile from the Delta to Lake Nasser. This change was likely due to the construction of huge water projects, the development of new water resources essential for land reclamation projects and the movement of refugees from the Suez Canal zone to the Delta and vice versa. The situation with respect to Biomphalaria in Egypt has become complicated in recent years by the detection of Biomphalaria glabrata and a hybrid between both species; however, follow-up studies have demonstrated the disappearance of such species within Egypt. The National Schistosoma Control Program has made great strides with respect to the eradication of schistosoma; however, there has unfortunately been a reemergence of Schistosoma mansoni resistant to praziquantel. There are numerous factors that may influence the prevalence of snails in Egypt, including the construction of water projects, the increase in reclaimed areas, global climate change and pollution. Thus, continued field studies in addition to the cooperation of several scientists are needed to obtain an accurate representation of the status of this species. In addition, the determination of the genome sequence for Biomphalaria alexandrina and the

  1. Biomphalaria alexandrina in Egypt: past, present and future.

    Science.gov (United States)

    Abou-El-Naga, Iman F

    2013-09-01

    The African species of Biomphalaria appeared as a result of the relatively recent west-to-east trans-Atlantic dispersal of the Biomphalaria glabrata-like taxon. In Egypt, Biomphalaria alexandrina is the intermediate host for Schistosoma mansoni. Biomphalaria alexandrina originated in the area between Alexandria and Rosetta and has historically been confined to the Nile Delta. Schistosoma mansoni reached Egypt via infected slaves and baboons from the Land of Punt through migrations that occurred as early as the Vth Dynasty. The suggestion of the presence of Schistosoma mansoni infection in Lower Egypt during Pharaonic times is discussed despite the fact that that there is no evidence of such infection in Egyptian mummies. It is only recently that Biomphalaria alexandrina colonized the Egyptian Nile from the Delta to Lake Nasser. This change was likely due to the construction of huge water projects, the development of new water resources essential for land reclamation projects and the movement of refugees from the Suez Canal zone to the Delta and vice versa. The situation with respect to Biomphalaria in Egypt has become complicated in recent years by the detection of Biomphalaria glabrata and a hybrid between both species; however, follow-up studies have demonstrated the disappearance of such species within Egypt. The National Schistosoma Control Program has made great strides with respect to the eradication of schistosoma; however, there has unfortunately been a reemergence of Schistosoma mansoni resistant to praziquantel. There are numerous factors that may influence the prevalence of snails in Egypt, including the construction of water projects, the increase in reclaimed areas, global climate change and pollution. Thus, continued field studies in addition to the cooperation of several scientists are needed to obtain an accurate representation of the status of this species. In addition, the determination of the genome sequence for Biomphalaria alexandrina and the

  2. Freshwater snails and schistosomiasis mansoni in the State of Rio de Janeiro, Brazil: I - metropolitan mesoregion

    Directory of Open Access Journals (Sweden)

    Thiengo Silvana C

    2001-01-01

    Full Text Available In order to elaborate a planorbid chart of the State of Rio de Janeiro a survey of freshwater gastropods in the Metropolitan Mesoregion of this State was performed and revealed the occurrence of 20 species: Antillorbis nordestensis (Lucena, 1954; Biomphalaria glabrata (Say, 1818; Biomphalaria schrammi (Crosse, 1864; Biomphalaria straminea (Dunker, 1848; Biomphalaria tenagophila (Orbigny, 1835; Burnupia sp.; Drepanotrema anatinum (Orbigny, 1835; Drepanotrema cimex (Moricand, 1839; Drepanotrema lucidum (Pfeiffer, 1839; Ferrissia sp.; Gundlachia ticaga (Marcus & Marcus, 1962; Heleobia davisi Silva & Thomé, 1985; Lymnaea columella Say, 1817; Melanoides tuberculatus (Müller, 1774; Physa cubensis Pfeiffer, 1839; Physa marmorata Guilding, 1828; Pomacea sp.; Pomacea canaliculata (Lamarck, 1822; Pomacea lineata (Spix, 1827 and Pomacea sordida (Swainson, 1823. Among the planorbid species B. tenagophila was the most frequent, occurring in all municipalities surveyed. The present study extends the distribution of B. straminea in the State of Rio de Janeiro and reports new records for A. nordestensis, B. schrammi, G. ticaga, H. davisi and the genera Burnupia and Ferrissia. An account about the current transmission areas of schistosomiasis mansoni in this Mesoregion is presented as well.

  3. Nomina nova in Platyhelminthes pro Macrorhynchus von Graff, 1882 (non [Gmelin, 1801]; non Dunker, 1843), and Leptocleidus Mueller, 1936 (non Andrews, 1922).

    Science.gov (United States)

    Hornung, Jahn J

    2016-08-19

    Two genus-group names of flat-worms-Leptocleidus Mueller, 1936 and Macrorhynchus von Graff, 1882-are junior homonyms that are preoccupied by fossil diapsid reptile genera-Leptocleidus Andrews, 1922, and Macrorhynchus Dunker, 1843-and an extant teleost fish genus-Macrorhynchus [Gmelin, 1801] ex La Cépède, 1800. These are replaced by nomina nova (Pharyngodytes nom. nov.; Graffiellus nom. nov.). Macrorhynchus [Gmelin, 1801] is an objective senior synonym of Macrorhyncus Dumeríl, 1805 ex La Cépède, 1800 (syn. nov.), and a senior homonym of Macrorhynchus Dunker, 1843, and Macrorhynchus von Graff, 1882.

  4. Biomphalaria prona (Gastropoda: Planorbidae: a morphological and biochemical study

    Directory of Open Access Journals (Sweden)

    W. Lobato Paraense

    1992-06-01

    Full Text Available Two samples of Biomphalaria prona (Martens, 1873 from Lake Valencia (type locality and seven from other Venezuelan localities were studied morphologically (shell and reproductive system and biochemically (allozyme electrophoresis. In spite of marked differences in shell characters, all of them proved indistinguishable under the anatomic and biochemical criteria. So far B. prona has been considered an endemic species, restricted to Lake Valencia. It is now demonstrated that the extralacustrine populations refered to Biomphalaria havanensis (Pfeiffer, 1839 by several authors correspond in shell characters to an extreme variant of B. prona from the Lake and really belong to the last*mentioned species. They may be regarded as the result of a process of directional selection favoring a shell phenotype other than those making up the modal class in the Lake.

  5. Inheritance of Schistosoma mansoni infection incompatibility in Biomphalaria alexandrina snails

    OpenAIRE

    Iman F Abou El Naga; Eissa, Maha M.; Shereen F Mossallam; Safaa I Abd El-Halim

    2010-01-01

    In this study, we looked at the inheritance of susceptibility and resistance to Schistosoma mansoni infection in the first generation of crossbred Biomphalaria alexandrina snails. Our ultimate goal is to use such information to develop a biological method of controlling schistosomiasis. We infected laboratory-bred snails with S. mansoni miracidia and examined cercarial shedding to determine susceptibility and resistance. Five parental groups were used: Group I contained 30 susceptible snails,...

  6. Marcacao de caramujos Biomphalaria glabrata por radionuclideos para trabalhos em campos Radionuclide labeling of Biomphalaria glabrata snails for fiel studies

    Directory of Open Access Journals (Sweden)

    Miguel Archanjo Muniz Leal

    1982-03-01

    Full Text Available Os autores marcam caramujos Biomphalaria glabrata com 75Se, 59Fe, 89Sr e 90Sr e através das curvas de captação, decaimento e distribuição dos radionuclídeos na concha/partes moles do caramujo, concluem que o radioestrõncio pode ser utilizado em experiências em campo sobre dispersão e dinâmica de população de caramujos.The authors mark snails Biomphalaria glabrata with 75Se, 59Fe, 89Sr and 90Sr and through curves of uptake and decay and distribution of the radionuclides in the shell/soft parts conclude that radiostrontium can be used in field experiments on dispersion and dynamics of snail populations.

  7. Differentiation of the sibling species Biomphalaria occidentalis and Biomphalaria tenagophila by the electrophoretic patterns of their hemoglobin

    Directory of Open Access Journals (Sweden)

    James B. Bailey

    1986-09-01

    Full Text Available A simple and rapid method for differentialing the sibling species Biomphalaria tenagophila and Biomphalaria occidentalis by agarose gel electrophoresis (AGE is described. Snail hemolymph is used as the test sample and the red colaration of the hemoglobin fraction permits visualization of the migration patterns without resorting to specific stains. Moreover, hemolymph samples may be obtained without killing the snail, thus permitting its use for other studies for breeding.É descrito um método simples e rápido para distinguir as espécies crípticas Biomphalaria tenagophila e B. occidentalis por eletroforese em gel de agarose. A prova é feita com hemolinfa do molusco, permitindo a cor vermelha da fração hemoglobina visualizar os padrões de migração sem necessidade de recorrer a colorações específicas. Além disso, as amostras de hemolinfa podem ser obtidas sem sacrificar o molusco, que poderá ser usado para outros estudos ou para criação.

  8. A bird's eye survey of central american planorbid molluscs

    Directory of Open Access Journals (Sweden)

    Paraense W Lobato

    2003-01-01

    Full Text Available In the course of two trips to Central America (June 1967 and JulyAugust 1976 I had the opportunity of collecting topotypic specimens of Planorbis nicaraguanus Morelet, 1849, anatomically defined in this paper, and of P. yzabalensis Crosse & Fischer, 1879, the identity of the latter with Drepanotrema anatinum (Orbigny, 1835 is confirmed. The following planorbid species were also found: Helisoma trivolvis (Say, 1817 in Nicaragua, Guatemala, Costa Rica and Belize; H. duryi (Wetherby, 1879 in Costa Rica; Biomphalaria helophila (Orbigny, 1835 in Guatemala, Belize, Nicaragua, Costa Rica and El Salvador; B. kuhniana (Clessin, 1883 in Panama; B. obstructa (Morelet,1849 in Guatemala, Belize and El Salvador; B. straminea (Dunker, 1848 in Costa Rica; B. subprona (Martens, 1899 in Guatemala; D. anatinum (Orbigny,1835 in Belize, Guatemala, Nicaragua and Costa Rica; D. depressissimum (Moricand,1839 in Nicaragua, Costa Rica and Panama; D. lucidum (Pfeiffer, 1839 in Guatemala, Belize and Nicaragua; D. surinamense (Clessin, 1884 in Costa Rica and Panama; and Gyraulus percarinatus sp. n. in Panama. The occurrence of B. kuhniana and D. surinamense is first recorded in Central America, and Gyraulus percarinatus is the first representative of the genus provenly occurring in the American continent south of the United States. The following synonymy is proposed: Planorbis declivis Tate, 1870 = Biomphalaria helophila (Orbigny, 1835; Planorbis isthmicus Pilsbry, 1920 = Biomphalaria kuhniana (Clessin, 1883; Planorbis cannarum Morelet, 1849 and Segmentina donbilli Tristram, 1861 = Biomphalaria obstructa (Morelet, 1849; and Planorbis yzabalensis Crosse & Fischer, 1879 = Drepanotrema anatinum (Orbigny, 1835, confirming Aguayo (1933.

  9. Phylogenetic analysis of Biomphalaria tenagophila (Orbigny, 1835 (Mollusca: Gastropoda

    Directory of Open Access Journals (Sweden)

    Liana K Jannotti-Passos

    2010-07-01

    Full Text Available Mitochondrial DNA of Biomphalaria tenagophila, a mollusc intermediate host of Schistosoma mansoni in Brazil, was sequenced and characterised. The genome size found for B. tenagophila was 13,722 bp and contained 13 messenger RNAs, 22 transfer RNAs (tRNA and two ribosomal RNAs (rRNA. In addition to sequencing, the mitochondrial DNA (mtDNA genome organization of B. tenagophila was analysed based on its content and localization of both coding and non-coding regions, regions of gene overlap and tRNA nucleotide sequences. Sequences of protein, rRNA 12S and rRNA 16S nucleotides as well as gene organization were compared between B. tenagophila and Biomphalaria glabrata, as the latter is the most important S. mansoni intermediate host in Brazil. Differences between such species were observed regarding rRNA composition. The complete sequence of the B. tenagophila mitochondrial genome was deposited in GenBank (accession EF433576. Furthermore, phylogenetic relationships were estimated among 28 mollusc species, which had their complete mitochondrial genome deposited in GenBank, using the neighbour-joining method, maximum parsimony and maximum likelihood bootstrap. B. tenagophila was positioned at a branch close to B. glabrata and Pulmonata molluscs, collectively comprising a paraphyletic group, contrary to Opistobranchia, which was positioned at a single branch and constituted a monophyletic group.

  10. Weight loss and survival of Biomphalaria Glabrata deprived of water

    Directory of Open Access Journals (Sweden)

    Marc Vianey-Liaud

    1986-06-01

    Full Text Available Immature and mature Biomphalaria glabrata are kept out of water at relative humidities varying from 0 to 100%. When snails are submitted to a saturated atmosphere, they show a slow weight loss and survival may be long. If relative humidity (RH decreases, weight loss becomes important and survival is short. A reduced RH (0 to 65% produces similar effects. During desiccation, fasting has no noticeable effect; survival depends essentially on weight loss.Biomphalaria glabrata maduros ou imaturos são mantidos fora da água, variando a umidade de 0 a 100%. Quando caramujos são submetidos a uma atmosfera saturada, sofrem uma lenta perda de peso e a sobrevivência pode ser longa. Se a umidade relativa decresce, a perda de peso será importante e a sobrevida será abreviada. Uma umidade relativa de 0 a 65% pode produzir efeitos similares. Durante a dessecação, a privação de alimento não tem efeito notável, a sobrevivência dependendo essencialmente da perda de peso.

  11. Identification of Biomphalaria havanensis and Biomphalaria obstructa populations from Cuba using polymerase chain reaction and restriction fragment length polymorphism of the ribosomal RNA intergenic spacer

    Directory of Open Access Journals (Sweden)

    Teofânia HDA Vidigal

    2001-07-01

    Full Text Available In Cuba, several Biomphalaria species have been reported such as B. orbignyi, B. schrammi, B. helophila, B. havanensis and B. peregrina; only the latter three are considered as potential hosts of Schistosoma mansoni. The specific identification of Biomphalaria species is based on anatomical and morphological characters of genital organs and shells. The correct identification of these snails is complicated by the high variation in these characters, similarity among species and in some cases by the small size of the snails. In this paper, we reported the classical morphological identification, the use of PCR and RFLP analysis of the internal transcribed spacer region of the ribosomal RNA genes for molecular identification of seven snail populations from different localities in Cuba. Using morphological and molecular analysis, we showed that among the studied Cuban Biomphalaria populations only B. havanensis and B. obstructa species were found.

  12. Nueva especie de Planorbidae (Gastropoda: Basommatophora en la Patagonia chilena: Biomphalaria cristiani sp. nov. First record of Planorbidae (Mollusca: Basommatophora in Chilean Patagonia: Biomphalaria cristiani sp. nov.

    Directory of Open Access Journals (Sweden)

    Carmen Fuentealba

    2012-11-01

    Full Text Available En Chile la familia Planorbidae está representada por el género Biomphalaria Preston, 1910, compuesta por siete especies distribuidas desde Isluga hasta el río Puelo. De estas especies, solo B.peregrina, ampliamente distribuida en el neotrópico, y Biomphalaria aymara de Isluga, han sido reconocidas sobre la base de la morfología del sistema reproductor y la rádula, caracteres que fueron utilizados en el presente estudio para diferenciar a Biomphalaria cristiani como nueva especie del grupo y primer registro de la familia en la Patagonia chilena, ampliando su actual rango de distribución. Los caracteres que permiten la diagnosis de B. cristiani son el saco vaginal vestigial truncado, ausencia del desarrollo de los músculos suspensores del pene, vaina del pene corta en relación al prepucio, oviducto largo en relación al espermioducto y vaso deferente más delgado y largo que la vaina del pene, de tamano similar al prepucio. La localidad tipo de Biomphalaria cristiani sp. nov. es Laguna Cisnes (47°7'10.02"S, 72°27'40.65"W, región de Aysén.The family Planorbidae in Chile is represented by the genus Biomphalaria Preston, 1910, consisting of seven species distributed from Isluga to Puelo River. Of these species, only Biomphalaria peregrina widely distributed in the neotropical and Biomphalaria aymara from Isluga are recognized based on the morphology of the reproductive system and radula, characters that were used in the following study to differentiate Biomphalaria cristiani as a new species of this group and first record of the family in Chilean Patagonia, extending its current distribution range. The characters for the diagnosis of B. cristiani are: truncated vestigial vaginal pouch, lack of development of the penis retractor muscles, penis sheath shorter than the prepuce, oviduct longer than the spermiduct and vas deferens thinner and longer than the penis sheath, similar size to the prepuce. The type locality of B. cristiani nov. sp

  13. Compatibility of Ugandan Schistosoma mansoni isolates with Biomphalaria snail species from Lake Albert and Lake Victoria

    DEFF Research Database (Denmark)

    Adriko, Moses; Standley, Claire J.; Tinkitina, Benjamin

    2013-01-01

    In order to investigate the capacity of being intermediate host for Schistosoma mansoni, the Ugandan F1 generation of Biomphalaria snail species that were laboratory-bred from parent populations originally collected from either Lake Victoria or Lake Albert was challenged with sympatric and non......-sympatric S. mansoni isolates. After a prepatent period of 20 days, a daily 10-hourly snail shedding for cercariae was done to determine the infection rate, cercarial production per hour and survival period of infected snails. The study suggests that when parasite strains from a different geographical origin...... is used for infection, survival of infected snails increase, leading to an increased transmission potential. Although earlier literature had indicated that the Lake Victoria Biomphalaria sudanica is refractory to S. mansoni, we showed that all Ugandan Biomphalaria spp., including B. sudanica from all...

  14. Identification of the immune expressed sequence tags of pearl oyster (Pinctada martensii, Dunker 1850) responding to Vibrio alginolyticus challenge by suppression subtractive hybridization.

    Science.gov (United States)

    Wang, Yanhong; Fu, Dingkun; Luo, Peng; He, Xiaocui

    2012-09-01

    One hemolymph subtracted cDNA library of pearl oyster (Pinctada martensii, Dunker 1837) was constructed using the suppression subtractive hybridization (SSH) in response to Vibrio alginolyticus. A total of 1089 clones were sequenced. All the consensuses were recognized based on the BLAST searches in NCBI, and revealed that 376 (58%) of them had no significant matches to reported sequences in the database. 267 ESTs were in significant matches after homologous sequence searches. Hypothesized genes inferred from EST sequences were categorized into six groups according to their putative biological functions: replication, transcription and translation; cellular processes; responded to stimuli; metabolism and biosynthesis; signal transduction genes; "other" category. The five genes, pearlin gene promoter PGPPm, serine/threonine kinase STKPm, limbic system-associated membrane protein LSAMPPm, nacrein gene intron 6 NGIPm6 and ferritin-like protein FLPPm, were analyzed using real-time PCR. All these genes were significantly expressed after V. alginolyticus challenge.

  15. Report on the Temporary Rearing Technique of Solen grandis Dunker%大竹蛏亲体暂养技术简报

    Institute of Scientific and Technical Information of China (English)

    侯和要; 彭作波; 林玉川; 王君霞

    2004-01-01

    通过对大竹蛏(Solen grandis Dunker)亲蛏(体长9~12 cm,体重45.76±6.78 g)从采捕运输到人工暂养培育的一系列试验工作,结果表明:亲蛏的挑选以体长9~13 cm、活泼健康、肥满度好的3龄个体为最佳.经7天试验,采用细沙作为底质进行亲蛏暂养的效果良好,成活率达98.5%,个体排卵量约300万粒;不铺任何底质暂养的亲蛏,成活率仅16.4%,不能正常排放精卵.

  16. Contribution to the histology of Biomphalaria glabrata Contribuição à histologia da Biomphalaria glabrata

    Directory of Open Access Journals (Sweden)

    Queli Teixeira Lemos

    1999-08-01

    Full Text Available A combination of histological techniques applied to the study of Biomphalaria glabrata yielded some interesting new data about the histology of this snail, a major intermediate host of Schistosoma mansoni in Brazil. Three kinds of pigments were identified: a dark pigment which bleached following oxidation with potassium permanganate; a lipofuchsin-like, diastase-resistant PAS-positive pigment and an iron-containing pigment, probably related to hemosiderin. Calcium was detected in small deposits within the connective tissue and forming a dense core inside the chitinous radular teeth. The presence of fibrils, staining with sirius-red and birefringence under polarized light strongly suggest primitive collagen tissue. The radular apparatus appeared as a storing site for glycogen, while abundant Alcian-blue positive material (proteoglycans was extremely concentrated in the radular sac.Uma combinação de várias técnicas histológicas permitiu alguns achados de interesse para a histologia da Biomphalaria glabrata, principal hospedeiro intermediário do Schistosoma mansoni no Brasil. Três tipos de pigmentos foram identificados: um pigmento escuro, que se descora após oxidação pelo permanganato de potássio; outro que é semelhante à lipofuscina, que se cora pelo PAS e é diastase- resistente, e um pigmento que contém ferro, provalvelmente, relacionado com a hemossiderina. O cálcio foi identificado em pequenos depósitos no interior do tecido conjuntivo e formando pequenos núcleos no interior dos dentes quitinosos da rádula. A presença de fibrilas coradas pelo sírius-vermelho, exibindo birrefrigência sob luz polarizada, sugere fortemente a presença de um tecido colágeno primitivo. O aparelho radular foi visto como um local de armazenamento do glicogênio, enquanto a presença de abundante material amorfo positivo para o azul de alciano (proteoglicano apareceu em grande concentração no saco radular.

  17. Cercarial production from Biomphalaria alexandrina infected with Schistosoma mansoni.

    Science.gov (United States)

    Chu, K Y; Dawood, I K

    1970-01-01

    The present paper deals with longitudinal and cross-sectional methods of counting cercariae shed from Biomphalaria alexandrina in Egypt, both experimentally and naturally infected with schistosomes. By the longitudinal method, the daily output of cercariae was counted from the first shedding from experimentally infected snails and from the day of collection from naturally infected ones. The results show that the size of the snails at the time of shedding exerts a very large effect on the output of cercariae and that the numbers obtained in the laboratory are not representative of cercarial output in the field. By the cross-sectional method, the cercarial output in the first 24 hours from infected snails collected in different months from the field was counted. The results show that output is size-specific. When the size-specific output is adjusted to the size-composition of infected snails taken from the field, it is estimated that the daily output from infected snails in the field may be 957.7 cercariae. However, this number may vary with the season.

  18. Compatibility of Schistosoma mansoni Cameroon and Biomphalaria pfeifferi Senegal.

    Science.gov (United States)

    Southgate, V R; Tchuenté, L A; Théron, A; Jourdane, J; Ly, A; Moncrieff, C B; Gryseels, B

    2000-11-01

    The vectorial capacity of Biomphalaria pfeifferi from Ndiangue, Senegal, was investigated with an allopatric isolate of Schistosoma mansoni from Nkolbisson, Cameroon. The snail infection rate after exposure to a single miracidium per snail (MD1) was 56. 3 %, and 91.6%, for snails exposed to 5 miracidia per snail (MD5). The minimum pre-patent period was 21 days. The mean total cercarial production for the MDI group was 18,511 cercariae per snail, and 9757 cercariae for the MD5 group. The maximum production of cercariae for 1 day was 4892 observed in a snail from the MDI group at day 43 post-infection. The mean longevity of snails was higher in group MD1 (88 days p.i.) than in group MD5 (65 days p.i.). The chronobiological emergence pattern revealed a circadian rhythm with one shedding peak at mid-day. Comparisons are made with the vectorial capacity of the sympatric combination of B. pfeifferi Senegal/S. mansoni Senegal.

  19. Inheritance of Schistosoma mansoni infection incompatibility in Biomphalaria alexandrina snails

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    Iman F Abou El Naga

    2010-03-01

    Full Text Available In this study, we looked at the inheritance of susceptibility and resistance to Schistosoma mansoni infection in the first generation of crossbred Biomphalaria alexandrina snails. Our ultimate goal is to use such information to develop a biological method of controlling schistosomiasis. We infected laboratory-bred snails with S. mansoni miracidia and examined cercarial shedding to determine susceptibility and resistance. Five parental groups were used: Group I contained 30 susceptible snails, Group II contained 30 resistant snails, Group III contained 15 susceptible and 15 resistant snails, Group IV contained 27 susceptible and three resistant snails and Group V contained three susceptible and 27 resistant snails. The percentage of resistant snails in the resulting progeny varied according to the ratio of susceptible and resistant parents per group; they are 7%, 100%, 68%, 45% and 97% from Groups I, II, III, IV and V, respectively. On increasing the percentage of resistant parent snails, the percentage of resistant progeny increased, while cercarial production in their susceptible progeny decreased.

  20. On the origin of the Biomphalaria glabrata hemocytes

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    Samaly dos Santos Souza

    2006-10-01

    Full Text Available A histologic, morphometric and ultrastructural study performed on Biomphalaria glabrata submitted to infection with Schistosoma mansoni miracidia failed to provide significant evidences that the so-called amebocyte-producing organ (APO is really the central organ for hemocyte production. In infected snails no general reactive changes appeared in the APO, the mitoses were seen only occasionally, and the possibility of cellular hyperplasia was ruled out by morphometric measurements. Under the electron microscope the APO cells presented an essentially epithelial structure, without features indicative of transition toward hemocytes. On the other hand, the present findings pointed to a multicentric origin for the mollusck hemocytes, as earlier studies had indicated. Dense foci of hemocyte collections appeared sometimes around disintegrating sporocysts and cercariae in several organs and tissues of the infected snails, including a curious accumulation of such cells inside the ventricular cavity of the heart. In the heart and other sites, features suggestive of transformation of vascular space endothelial lining cells into hemocytes were apparent. To some extent, the postulated multicentric origin for B. glabrata hemocytes recapitulates earlier embryologic findings in vertebrates, when mesenchymal vascular spaces generate the circulating and phagocytic blood cells.

  1. Seleção genética de Biomphalaria glabrata e Biomphalaria tenagophila visando a alteração da suscetibilidade e resistência ao Schistosoma mansoni Genetic selection of Biomphalaria glabrata and Biomphalaria tenagophila seeking the alteration of the susceptibility and resistance to the Schistosoma mansoni

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    Nádia Regina Borim Zuim

    2005-10-01

    Full Text Available Gerações 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 adaptação do trematódeo ao hospedeiro intermediário. As gerações dos planorbídeos foram obtidas por autofecundação dos moluscos que se apresentaram suscetíveis ou resistentes após a exposição aos miracídios de Schistosoma mansoni. Para Biomphalaria glabrata foram obtidas as gerações: Parental, F1S (Suscetível, F1R (Resistente, F2S e F2R. Para a Biomphalaria tenagophila foram estudadas as gerações: Parental, F1S, F1R e F50S. A comparação das taxas de infecção apresentadas pelas diferentes gerações 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 implicações epidemiológicas.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.

  2. Genetic Variation between Biomphalaria alexandrina Snails Susceptible and Resistant to Schistosoma mansoni Infection

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    Suzanne M. F. El-Nassery

    2013-01-01

    Full Text Available Much effort has been made to control schistosomiasis infection in Egypt. However, enduring effects from such strategies have not yet been achieved. In this study, we sought to determine the genetic variability related to the interaction between Biomphalaria alexandrina snails and Schistosoma mansoni. Using RAPD-PCR with eight (10 mers random primers, we were able to determine the polymorphic markers that differed between snails susceptible and resistant to Schistosoma mansoni infection using five primers out of the eight. Our results suggest that the RAPD-PCR technique is an efficient means by which to compare genomes and to detect genetic variations between schistosomiasis intermediate hosts. The RAPD technique with the above-noted primers can identify genomic markers that are specifically related to the Biomphalaria alexandrina/Schistosoma mansoni relationship in the absence of specific nucleotide sequence information. This approach could be used in epidemiologic surveys to investigate genetic diversity among Biomphalaria alexandrina snails. The ability to determine resistant markers in Biomphalaria alexandrina snails could potentially lead to further studies that use refractory snails as agents to control the spread of schistosomiasis.

  3. Alien Planorbid (Mollusca, Gastropoda Pulmonata) from South West Africa erroneously recorded as Biomphalaria Pfeifferi

    NARCIS (Netherlands)

    Bruggen, van A.C.

    1974-01-01

    In 1970 I published a record of the freshwater snail Biomphalaria pfeifferi (Krauss, 1848) (fam. Planorbidae) for South West Africa: "Sandamap Farm, Spitzkoppe" (Van Bruggen, 1970: 45, figs. 1-13). Dr. D. S. Brown of the Medical Research Council (London) kindly drew my attention to the fact that jud

  4. Genetic variation between Biomphalaria alexandrina snails susceptible and resistant to Schistosoma mansoni infection.

    Science.gov (United States)

    El-Nassery, Suzanne M F; Abou-El-Naga, Iman F; Allam, Sonia R; Shaat, Eman A; Mady, Rasha F M

    2013-01-01

    Much effort has been made to control schistosomiasis infection in Egypt. However, enduring effects from such strategies have not yet been achieved. In this study, we sought to determine the genetic variability related to the interaction between Biomphalaria alexandrina snails and Schistosoma mansoni. Using RAPD-PCR with eight (10 mers) random primers, we were able to determine the polymorphic markers that differed between snails susceptible and resistant to Schistosoma mansoni infection using five primers out of the eight. Our results suggest that the RAPD-PCR technique is an efficient means by which to compare genomes and to detect genetic variations between schistosomiasis intermediate hosts. The RAPD technique with the above-noted primers can identify genomic markers that are specifically related to the Biomphalaria alexandrina/Schistosoma mansoni relationship in the absence of specific nucleotide sequence information. This approach could be used in epidemiologic surveys to investigate genetic diversity among Biomphalaria alexandrina snails. The ability to determine resistant markers in Biomphalaria alexandrina snails could potentially lead to further studies that use refractory snails as agents to control the spread of schistosomiasis.

  5. A New Method for Fixing Biomphalaria glabrata for Histologic Studies, Using Shell Perforation

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    Barbosa Luciene

    2002-01-01

    Full Text Available A new technique for fixation of Biomphalaria glabrata for histologic studies is described. It consists in performing several external holes in the shell, before placing the entire snail into the fixative. It is a very practical and quick procedure that showed excellent results when compared to the usual techniques.

  6. Construction of a full-length cDNA library of Solen grandis dunker and identification of defense- and immune-related genes

    Science.gov (United States)

    Sun, Guohua; Liu, Xiangquan; Ren, Lihua; Yang, Jianmin; Wei, Xiumei; Yang, Jialong

    2013-11-01

    The basic genetic characteristics, important functional genes, and entire transcriptome of Solen grandis Dunker were investigated by constructing a full-length cDNA library with the `switching mechanism at the 5'-end of the RNA transcript' (SMART) technique. Total RNA was isolated from the immune-relevant tissues, gills and hemocytes, using the Trizol reagent, and cDNA fragments were digested with Sfi I before being ligated to the pBluescript II SK* vector. The cDNA library had a titer of 1048 cfu μL-1 and a storage capacity of 1.05×106 cfu. Approximately 98% of the clones in the library were recombinants, and the fragment lengths of insert cDNA ranged from 0.8 kb to 3.0 kb. A total of 2038 expressed sequence tags were successfully sequenced and clustered into 965 unigenes. BLASTN analysis showed that 240 sequences were highly similar to the known genes (E-value 80%), accounting for 25% of the total unigenes. According to the Gene Ontology, these unigenes were related to several biological processes, including cell structure, signal transport, protein synthesis, transcription, energy metabolism, and immunity. Fifteen of the identified sequences were related to defense and immunity. The full-length cDNA sequence of HSC70 was obtained. The cDNA library of S. grandis provided a useful resource for future researches of functional genomics related to stress tolerance, immunity, and other physiological activities.

  7. Benthic communities on hard substrates covered by Limnoperna fortunei Dunker (Bivalvia, Mytilidae at an estuarine beach (Río de la Plata, Argentina

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    Fernando G. Spaccesi

    2012-01-01

    Full Text Available The structure and composition of benthic communities on hard substrates covered by the nonindigenous bivalve Limnoperna fortunei Dunker, the golden mussel, were quantified in the middle zone of the Río de la Plata Estuary (Argentina from April 2001 through March 2002. A total of 26 taxa were recorded. L. fortunei and Nematoda were the central and dominant groups, with a prodigious abundance of over 80%. The prevalence of L. fortunei, rather than the environmental variables, regulated the dynamics of the associated invertebrate fauna. The golden mussel alters both the structure and function of benthic native communities on hard substrates, allows a higher surface available for colonization and refuge, and provides food source to deposit-feeding organisms in the form of organic or residual material. The mussel also increases the abundance and diversity of taxa on hard substrata - such as Oligochaeta, Hirudinea, Tardigrada, Chironomidae, Copepoda, Tanaidacea, and Hydrachnidia. Similarities and nonparametric multidimensional-scaling analyses indicated that the benthic composition had a seasonal variation. L. fortunei has an environmental impact, an ability to invade new freshwater ambiences worldwide and ecological characteristic comparable to those of Dreissena polymorpha Pallas (the zebra mussel of North America and Europe.

  8. Mass migration of juvenile Biomphalaria glabrata snails bred under semi-natural conditions

    OpenAIRE

    Frederico Simões Barbosa

    1989-01-01

    For the development of studies on snail interspecific competition special in-door laboratory channels were built. In the all five channels seeded with adult specimens of Biomphalaria glabrata mass migration of juvenile snails outside the water was observed. Most of the migrant snails presented apertural lamellae. Data collected during the period of two years, showed the regression of the migration phenomenon and the disappearance of the lamellate snails.

  9. A bacterial artificial chromosome library for Biomphalaria glabrata, intermediate snail host of Schistosoma mansoni

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    Coen M Adema

    2006-10-01

    Full Text Available To provide a novel resource for analysis of the genome of Biomphalaria glabrata, members of the international Biomphalaria glabrata Genome Initiative (biology.unm.edu/biomphalaria-genome.html, working with the Arizona Genomics Institute (AGI and supported by the National Human Genome Research Institute (NHGRI, produced a high quality bacterial artificial chromosome (BAC library. The BB02 strain B. glabrata, a field isolate (Belo Horizonte, Minas Gerais, Brasil that is susceptible to several strains of Schistosoma mansoni, was selfed for two generations to reduce haplotype diversity in the offspring. High molecular weight DNA was isolated from ovotestes of 40 snails, partially digested with HindIII, and ligated into pAGIBAC1 vector. The resulting B. glabrata BAC library (BG_BBa consists of 61824 clones (136.3 kb average insert size and provides 9.05 × coverage of the 931 Mb genome. Probing with single/low copy number genes from B. glabrata and fingerprinting of selected BAC clones indicated that the BAC library sufficiently represents the gene complement. BAC end sequence data (514 reads, 299860 nt indicated that the genome of B. glabrata contains ~ 63% AT, and disclosed several novel genes, transposable elements, and groups of high frequency sequence elements. This BG_BBa BAC library, available from AGI at cost to the research community, gains in relevance because BB02 strain B. glabrata is targeted whole genome sequencing by NHGRI.

  10. Evaluation of radiosensitivity hemocytes of Biomphalaria glabrata exposed to gamma radiation; Avaliacao da radiossensibilidade de hemocitos de Biomphalaria glabrata expostos a radiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Silva, L.R.S.; Amaral, A.J., E-mail: luannaribeiro_lua@hotmail.com [Universidade Federal de Pernambuco (UFPE), Recife-PE (Brazil). Dept. de Energia Nuclear; Silva, E.B. [Universidade Federal de Pernambuco (UFPE), Vitoria de Santo Antao, PE (Brazil). Centro Academico de Vitoria; Amancio, F.F.; Melo, A.M.M.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia

    2013-06-15

    The mollusc Biomphalaria glabrata have characteristics that allow them to be identified as an animal model ideal for monitoring areas exposed to chemical agents and physical. This study evaluated the effect of ionizing radiation from Cobalt-60 in haemocytes present in the hemolymph of Biomphalaria glabrata, with the goal of using these cells as indicators of the presence of radiation in aquatic environments. The mollusks were divided into five groups: one control and four subjected doses of 25, 35, 45 and 55 Gy of gamma radiation. After 48 hours of irradiation, the clam hemolymph was collected and slides were prepared and stained with Giemsa for analyses under a light microscope. Statistical analysis was performed using ANOVA and Tukey's test, p <0.05. The results showed that the total number of cells after irradiation reduced compared to control except at a dose of 55 Gy. During data analysis, morphological changes were observed in haemocytes of mollusks subjected to doses of 35, 45 and 55 Gy. These modifications consisted of nucleus bilobulated and nucleo plasmatic bridges. Another change was exclusively observed in the cellular exposure of 55 Gy, where hemocytes showed misshapen nuclei and cytoplasm vacuolisation, suggestive of apoptosis. It is concluded that hemocytes are sensitive to radiation and can be used as indicators of the presence of high doses of ionizing radiation in aquatic environments. (author)

  11. Prospecção do molusco invasor Limnoperna fortunei (Dunker, 1857 nos principais corpos hídricos do estado do Paraná, Brasil

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    Debora Pestana

    2010-01-01

    Full Text Available Foram realizadas coletas nos principais corpos hídricos do Paraná objetivando a prospecção de larvas do mexilhão dourado, Limnoperna fortunei (Dunker, 1857. Essa espécie de molusco vem colonizando diversos corpos hídricos na América do Sul desde sua introdução na Argentina, em 1991. Já atingiu os rios Paraná e Paraguai, tendo sua presença reportada nos estados do Mato Grosso do Sul, Paraná, São Paulo, Minas Gerais e Rio Grande do Sul. As coletas foram feitas no inverno e na primavera de 2007 e no verão e no outono de 2008, em 14 pontos amostrais ao longo dos rios Iguaçu, Piquiri, Ivaí (afluentes do rio Paraná e Tibagi (afluente do rio Paranapanema. O presente estudo determinou a presença da espécie ao longo de todos os pontos do rio Iguaçu, em dois pontos do rio Piquiri e um ponto amostral do rio Tibagi. No rio Ivaí, sua presença não foi detectada em nenhum dos pontos, em nenhuma estação do ano. Com base nos resultados obtidos, foi feito um mapa de ocorrência da espécie no estado do Paraná. Esses resultados são úteis para embasar a tomada de decisão a respeito do avanço da espécie, no sentido de monitorar sua presença e/ou prevenir sua entrada em outros corpos hídricos do estado.Were collected in the main water bodies of the state of Paraná (Brazil it will seek the golden mussel larvae, Limnoperna fortunei (Dunker, 1857. This species of mussel is colonizing various water bodies in South America since its introduction in Argentina in 1991. Already reached the Paraná and Paraguay rivers, having reported their presence in the states of Mato Grosso do Sul, Paraná, Sao Paulo, Minas Gerais and Rio Grande do Sul. Samples were collected in winter and spring of 2007 and summer and autumn 2008 in 14 sampling points along the rivers Iguaçu, Piquiri, Ivaí (tributaries of the Paraná River and Tibagi (tributary of the Paranapanema river. This study determined the presence of this species throughout all parts of the

  12. Biomphalaria Tenagophila Guaibensis ssp. n. from Southern Brazil and Uruguay (pulmonata: Planorbidae. I. Morphology

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    W. Lobato Paraense

    1984-12-01

    Full Text Available A new subspecies of planorbid snail, biomphalaria tenagophila guaibensis, is described. It has been found along the coastal belt of the Brazilian state of rio grande do Sul and the middle part of Uruguay, from Porto Alegre to Mercedes. It differs from the nominate subspecies, Biomphalaria tenagophila tenagophila, in the appearance of the penial complex (prepuce longer and proportionally slenderer in B. t. guaibensis, shorter and proportionally stouter in b. t. tenagophila, in the ratio between the lengths of the penial sheath and the prepuce, in the ratio between the lengths of the uterine complex and the penial complex, and in a coefficient of difference of 2.44 for the ratio between the penis sheath and prepuce and of 2.02 for the ratio between the uterine complex and penial complex. The shell and the other organs of the genital system are similar in both subspecies. B. t. guaibensis is very similar to Biomphalaria occidentalis Paraense, 1981, but is readily separated from it by the presence of a vaginal pouch, which is lacking in the latter, besides showing highly significant difference in the penis sheath: prepuce and uterine complex: penial complex ratios. Crossbreeding experiments which lend additional support to the recognition of B. t. guaibensis as a subspecies will be reported elsewhere.É descrita uma nova subespécie de molusco planorbídeo, Biomphalaria tenagophila guaibensis, que tem sido encontrada ao longo da faixa costeira do Estado do Rio Grande do Sul e da parte média do Uruguai, de Porto Alegre a Mercedes. Distingue-se da espécie nominativa, Biomphalaria tenagophila tenagophila, pelo aspecto do complexo peniano (prepúcio mais longo e proporcionalmente mais delgado em B. t. guaibensis, mais curto e proporcionalmente mais grosso em b. t. tenagophila0, pela razão entre os comprimentos da bainha do pênis e do prepúcio, pela razão entre os comprimentos do complexo uterino e do complexo peniano, e por um coeficiente de

  13. Contribuição ao estudo da biologia de Biomphalaria occidentalis Paraense, 1981 e de Biomphalaria tenagophila (d'Orbigny, 1835, em condições de laboratório A contribution to the study of the biology of Biomphalaria occidentalis Paraense, 1981 and of Biomphalaria tenagophila (d'Orbigny, 1835, under laboratory conditions

    Directory of Open Access Journals (Sweden)

    Maísa Rose Domenico Elmor

    1992-10-01

    Full Text Available Com o objetivo de comparar a duração do período embrionário, a fecundidade e a fertilidade de Biomphalaria occidentalis Paraense, 1981 com a de B, tenagophila (d'Orbigny, 1835, exemplares de ambas as espécies foram criados em aquários dotados das mesmas características. Os ovos depostos pelos caramujos foram contados sob lupa binocular e seu desenvolvimento embrionário foi observado até a eclosão. Assim foi obtido o número total de posturas e de ovos por caramujo, bem como o número total de ovos eclodidos por postura para cada período de trinta dias, ou seja, a taxa de eclosão por período. O experimento teve a duração de doze meses e os resultados obtidos são válidos para condições de laboratório.Specimens of Biomphalaria occidentalis and Biomphalaria tenagophila were reared in S.Paulo, Brazil under laboratory conditions, with a view to know their biological characteristics. Oviposition and eggs/oviposition ratio were recorded over twelve months so as to obtain information on the number of egg-masses per animal and the number of eggs per egg-mass, as also the number of hatched eggs per egg-mass for each period of 30 days, i.e., the hatching-rate per period. The incubation period was about the same for both species, but the oviposition and egg oviposition ratio were greater in B. tenagophila.

  14. Duration of pairing and use of allosperm in Biomphalaria glabrata (Gastropoda: Planorbidae Duração do acasalamento e uso do aloesperma em Biomphalaria glabrata (Gastropode: Planorbidae

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    Marc Vianey-Liaud

    1989-03-01

    Full Text Available Virgin homozygous black pigmented and albino Biomphalaria glabrata are paired during a period varying from 1 to 20 days. The rate of cross-fertilized parents is statistically similar for the various lengths of pairing. As a whole, nearly 80% of the albino snails produce a pigmented progeny. This production begins as soon as the snails are mated and continues after their separation. To measure the actual use of the allosperm, its use during the postmating period must be added to the length of mating. So, it appears that the real use of the allosperm is statistically constant (mean slightly inferior to 8 weeks and not related to the length of the previous pairing.Espécimes virgens de Biomphalaria glabrata (um melâncio e um albino são acasalados durante um período variável de 1 a 20 dias. A proporção de espécimes parentais albinos fecundados por cruzamento é semelhante estatisticamente para os diversos períodos de acasalamento. Em conjunto, cerca de 80% dos albinos produziram descendência pigmentada. Essa produção começa assim que os moluscos são acasalados e continua depois que são separados. Para medir a utilização real do aloesperma, sua utilização durante o período de pós-acasalamento. Parece, assim, que a utilização real do aloesperma é estatisticamente constante (média ligeiramente inferior a oito semanas e não relacionada a duração do acasalamento anterior.

  15. Susceptibility of Biomphalaria amazonica and Biomphalaria occidentalis from Manso Dam, Mato Grosso, Brazil to infection with three strains of Schistosoma mansoni

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    Monica Ammon Fernandez

    2006-10-01

    Full Text Available As well as malaria and yellow fever, schistosomiasis is one of the main endemic diseases associated to environments which suffered some impact related to the development of great economic projects, as for example the construction of hydroelectric power stations. Aiming to investigate the occurrence and distribution of freshwater snails of medical and veterinary importance in the area which suffered impact from the Manso hydroelectric power station a survey was performed during the period of 2002 to 2003 and revealed the occurrence of populations of Biomphalaria amazonica and Biomphalaria occidentalis. Studies on parasite-mollusc compatibility were undertaken using five B. amazonica colonies (Barão de Melgaço, Poconé, Santo Antônio do Leverger, and Chapada dos Guimarães, in the Manso and Casca rivers, and four B. occidentalis colonies (Cuiabá, Santo Antônio do Leverger, and Chapada dos Guimarães, in the Água Fria district and Casca river were exposed to miracidia of Schistosoma mansoni. Of 257 snails of B. amazonica used, 17 became infected (infection index of 6.61% and all specimens of B. occidentalis proved unsusceptible. According to the strains used, of the 158 snails exposed to BH miracidia, 6 became infected (3.79%; of the 44 exposed to SJ miracidia, 6 became infected (13.63%; and of the 55 snails of B. amazonica exposed to EC miracidia, 5 became infected (9.09%. These results point out the low possibility of introduction of schistosomiasis in those areas, but we believe it can not be discarded as due the presence of B. amazonica.

  16. Caracterização da microbiota bacteriana de Biomphalaria glabrata (Say, 1818)(Mollusca: Gastropoda)

    OpenAIRE

    Silva, Tatiana Maria da

    2012-01-01

    Devido a grande importância da microbiota no desenvolvimento de parasitas nos invertebrados, muitos estudos vêm sendo desenvolvidos para o melhor entendimento desta interação. Desta forma, a associação entre microrganismos e seus hospedeiros invertebrados, vetores de doenças, está se tornando cada vez mais evidente. Com base nisto, o objetivo do presente estudo foi caracterizar a microbiota bacteriana de caramujos da espécie Biomphalaria glabrata, principal hospedeiro interm...

  17. Transmission studies of intestinal schistosomiasis in Lake Albert, Uganda and experimental compatibility of local Biomphalaria spp

    DEFF Research Database (Denmark)

    Kazibwe, F.; Makanga, B.; Rubaire-Akiiki, C.

    2010-01-01

    . Peak production times in both species were between 12.00 and 14.00h indicating greatest infection risk from lake water exposure is during the early afternoon. Laboratory-bred snails were exposed to locally hatched miracidia and susceptibility of Biomphalaria spp. was confirmed experimentally......) were culled and S. mansoni adult worms were retrieved from 10 animals. Taken as a whole, these observations highlight the local importance of B. stanleyi in transmission of intestinal schistosomiasis and clearly demonstrate the risk of infection on the Lake Albert shoreline. To mitigate this risk local...

  18. Sequential histological changes in Biomphalaria glabrata during the course of Schistosoma mansoni infection

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    Queli Teixeira Lemos

    2001-07-01

    Full Text Available Biomphalaria glabrata, highly susceptible to Schistosoma mansoni, were seen to shed less and less cercariae along the time of infection. Histological examination kept a close correlation with this changing pattern of cercarial shedding, turning an initial picture of no-reaction (tolerance gradually into one of hemocyte proliferation with formation of focal encapsulating lesions around disintegrating sporocysts and cercariae, a change that became disseminated toward the 142nd day post miracidial exposure. Findings were suggestive of a gradual installation of acquired immunity in snails infected with S. mansoni.

  19. Effect of self-fertilization on Biomphalaria tenagophila (Orbigny, 1835 (Pulmonata: Planorbidae

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    Tuan Roseli

    1998-01-01

    Full Text Available Biomphalaria tenagophila is a simultaneous hermaphrodite freshwater snail, which can breed by self and cross-fertilization. It is, therefore, well suited for studying reproduction as an evolutive strategy. Several characteristics (shell size and age at sexual maturity, egg fecundity and fertility were analyzed in four consecutive self-fertilized generations and compared to cross-fertilized individuals. The reproductive parameters were similar in the two groups. Shell size was significantly greater in the fourth self-fertilized generation than in the cross-fertilized individuals.

  20. Antigenic community between Schistosoma mansoni and Biomphalaria glabrata: on the search of candidate antigens for vaccines

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    N Chacón

    2002-10-01

    Full Text Available We have previously confirmed the presence of common antigens between Schistosoma mansoni and its vector, Biomphalaria glabrata. Cross-reactive antigens may be important as possible candidates for vaccine and diagnosis of schistosomiasis. Sera from outbred mice immunized with a soluble Biomphalaria glabrata antigen (SBgA of non-infected B. glabrata snails recognized molecules of SBgA itself and S. mansoni AWA by Western blot. Recognition of several molecules of the SBgA were inhibited by pre-incubation with AWA (16, 30, 36, 60 and 155 kDa. The only specific molecule of AWA, inhibited by SBgA, was a 120 kDa protein. In order to determine which epitopes of SBgA were glycoproteins, the antigen was treated with sodium metaperiodate and compared with non-treated antigen. Molecules of 140, 60 and 24 kDa in the SBgA appear to be glycoproteins. Possible protective effects of the SBgA were evaluated immunizing outbred mice in two different experiments using Freund's Adjuvant. In the first one (12 mice/group, we obtained a significant level of protection (46% in the total worm load, with a high variability in worm recovery. In the second experiment (22 mice/group, no significant protection was observed, neither in worm load nor in egg production per female. Our results suggest that SBgA constitutes a rich source of candidate antigens for diagnosis and prophylactic studies.

  1. Fases larvais do mexilhão dourado Limnoperna fortunei (Dunker (Mollusca, Bivalvia, Mytilidae na Bacia do Guaíba, Rio Grande do Sul, Brasil Larval stages of the golden mussel Limnoperna fortunei (Dunker (Bivalvia, Mytilidae in Guaíba Basin, Rio Grande do Sul State, Brazil

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    Cíntia P. dos Santos

    2005-09-01

    Full Text Available Desde o final de 1998, um pequeno bivalve invasor, o "mexilhão dourado", Limnoperna fortunei (Dunker, 1857, oriundo do sudeste asiático, está presente no sul do Brasil. Foi provavelmente transportado, não intencionalmente, através de água de lastro para a Bacia do Guaíba, Rio Grande do Sul, Brasil. Em nosso meio, este molusco vem causando problemas de "macrofouling" com grandes prejuízos econômicos e danos à fauna e flora. As coletas foram qualitativas e quantitativas quinzenais no período de um ano, no lago Guaíba, Praia do Veludo (30°12'35"S, 51°11'68"W, ao sul do município de Porto Alegre. Utilizou-se rede de plâncton com abertura de malha equivalente a 36 mm, filtrando-se a quantidade de 30 litros de água. Descrevem-se brevemente as diferentes fases larvais com parâmetros do comprimento. Primeiramente reconhece-se um estágio ciliado, desenvolvendo-se em trocófora (comprimento de 80 µm a 125 µm com quatro fases distintas, e valvadas com a larva "D" (120 µm a 150 µm, o veliger de charneira reta (150 µm a 190 µm, o veliger umbonado (190 µm a 220 µm e o pediveliger (220 µm a 250 µm. Quando pós-larvas ou plantígradas (comprimento em torno de 300 µm, começam a secretar o fio de bisso, permitindo a fixação ao substrato. Constatou-se a presença de larvas durante todos os meses amostrados, com picos nos meses de outubro a dezembro.Since the end of 1998 a small invasive bivalve, the golden mussel Limnoperna fortunei (Dunker, 1857, originating from Southeast Asia, is present in Southern Brazil. It was probably brought not intentionally in ballast water to the Guaíba Basin in Rio Grande do Sul State. In this environment, the golden mussel is causing macrofouling very rapidly with grate financial loss and damages to the native fauna and flora. Quali-quantitative samplings twice a month were performed during one year in the Guaíba lake, at Veludo Beach (30°12'35"S, 51°11'68"W southward of the municipality of Porto

  2. Compatibility in the Biomphalaria glabrata/Echinostoma caproni model: potential involvement of adhesion genes.

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    Bouchut, A; Roger, E; Coustau, C; Gourbal, B; Mitta, G

    2006-02-01

    Because susceptibility or resistance of Biomphalaria glabrata to the trematode Echinostoma caproni correlates with differential hemocytic adhesive properties, we compared the expression of genes involved in adhesion processes between hemocytes from susceptible and resistant snails. Quantitative reverse transcriptase-PCR analysis revealed four genes whose transcripts were differentially represented between hemocytes from resistant and susceptible snails. These genes encode two dermatopontin-like, one matrilin-like and one cadherin-like proteins. Expression analyses performed following parasite exposure suggested that dermatopontins may be involved in the compatibility differences between these strains. We also investigated expression levels on whole snails of different genes potentially involved in extracellular matrix structure or coagulation. Our results support the hypothesis that susceptible snails possess a hemolymph coagulation-like system that is more potent than that of resistant snails. This system may prevent hemocyte migration towards the parasite larvae and therefore facilitate parasite settlement in susceptible snails.

  3. Apparent competition through facilitation between Melanoides tuberculata and Biomphalaria glabrata and the control of schistosomiasis

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    Giovanelli Alexandre

    2003-01-01

    Full Text Available Interactions between two species that result in reduced growth rates for both and extinction of one of the species are generally considered cases of asymmetric interspecific competition. Exploitative or interference competition is the usual mechanism invoked. Here we describe another mechanism producing the same result, named apparent competition through facilitation (ACF, observed between Melanoides tuberculata and Biomphalaria glabrata populations. The superior competitor actually gives some benefit to the other species, whose population becomes unstable with progressively increasing oscillations, leading to extinction. A model of ACF using difference equations suggests initial dynamics distinct from traditional interspecific competition. The dynamics of two freshwater snails in the field and in laboratory experiments suggest ACF, and these relations should be considered in studies of schistosomiasis control. ACF could occur in natural populations, but might have gone undetected because the final result is similar to traditional interspecific competition.

  4. Genetical exchanges between one Biomphalaria glabrata (Gastropoda: Planorbidae and a varying number of partners Trocas genéticas entre uma Biomphalaria glabrata (Gastropoda: Planorbidae e um número variado de parceiros

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    Marc Vianey-Liaud

    1987-12-01

    Full Text Available When one pigmented Biomphalaria glabrata is mated with 1 to 20 albino snails, the percentage of albino parent producing pigmented offspring decreases while the percentage of parent laying albino offspring increases. If the number of snaisl/group increases, the mean duration of the use of allosperm decreases.Quando uma Biomphalaria glabrata pigmentada é posta em presença de um a vinte parceiros albinos, a percentagem de indivíduos parentais que produzem, por fecundação cruzada, uma descendência pigmentada, decresce. Ao contrário, a proporção de indivíduos parentais cuja descendência é de albinos aumenta. Quando o número de caramujos albinos por grupo aumenta, a duração média da utilização dos espermatozóides estranhos recebidos do parceiro pigmentado decresce.

  5. Sobre o encontro de Biomphalaria glabrata (Say, 1818 em dois municípios do Estado de São Paulo, Brasil The finding of Biomphalaria glabrata (Say, 1818 in two counties of S.Paulo State, Brazil

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    Horácio Manuel Santana Teles

    1986-06-01

    Full Text Available Relata-se o encontro de Biomphalaria glabrata (Say, 1818 em dois municípios do Estado de São Paulo (Brasil: Capital do Estado (São Paulo e Ribeirão Preto. No primeiro foram capturados exemplares melânicos na Represa Billings; no segundo, indivíduos albinos que colonizavam um aquário de peixes ornamentais.This study reports the finding of Biomphalaria glabrata (Say, 1818 in two counties of the State of S. Paulo (Brazil: in the capital (S.Paulo itself and in Ribeirão Preto. In the former melanic snails were collected from the Billings reservoir, in the latter collection was made of albinic specimens which had established a colony in an aquarium.

  6. Molecular approach for detecting early prepatent Schistosoma mansoni infection in Biomphalaria alexandrina snail host.

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    Farghaly, Adel; Saleh, Ayman A; Mahdy, Soad; Abd El-Khalik, Dalia; Abd El-Aal, Naglaa F; Abdel-Rahman, Sara A; Salama, Marwa A

    2016-09-01

    The present study aimed to evaluate a polymerase chain reaction (PCR) assay used for detection of Schistosoma mansoni infection in Biomphalaria alexandrina snails in early prepatent period and to compare between it and the ordinary detection methods (shedding and crushing). Biomphalaria alexandrina snails are best known for their role as intermediate hosts of S. mansoni. DNA was extracted from infected snails in addition to non-infected "negative control" (to optimized the efficiency of PCR reaction) and subjected to PCR using primers specific to a partial sequence of S. mansoni fructose-1,6-bus phosphate aldolase (SMALDO). SMALDO gene was detected in the infected laboratory snails with 70, 85, and 100 % positivity at the 1st, 3rd, and 7th day of infection, respectively. In contrast, the ordinary method was not sensitive enough in detection of early prepatent infection even after 7 days of infection which showed only 25 % positivity. By comparing the sensitivity of the three methods, it was found that the average sensitivity of shedding method compared to PCR was 23.8 % and the average sensitivity of crushing method compared to PCR was 46.4 % while the sensitivity of PCR was 100 %. We conclude that PCR is superior to the conventional methods and can detect positive cases that were negative when examined by shedding or crushing methods. This can help in detection of the areas and times of high transmission which in turn will be very beneficial in planning of the exact timing of the proper control strategy.

  7. Avaliação da bioatividade dos extratos de cúrcuma (Curcuma longa L., Zingiberaceae em Artemia salina e Biomphalaria glabrata Bioactivity evaluation of the turmeric (Curcuma longa L., Zingiberaceae extracts in Artemia salina and Biomphalaria glabrata

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    Carlos R. M. da Silva Filho

    2009-12-01

    Full Text Available A cúrcuma é o rizoma limpo, em boas condições, seco e moído da Curcuma longa L., uma planta herbácea da família Zingiberaceae. Visando novas alternativas para o controle da esquistossomose, os extratos de Curcuma longa L. foram testados para a avaliação da atividade moluscicida contra caramujos adultos da espécie Biomphalaria glabrata, e toxicidade (ensaio de letalidade com Artemia salina. A oleoresina e o óleo essencial de cúrcuma foram ativos contra Artemia salina (CL50 = 80,43 e CL50 = 319,82 μg/mL, respectivamente e também ativos contra os indivíduos adultos de Biomphalaria glabrata (CL50 = 58,3 e CL50 = 46,73 μg/mL, respectivamente. A partir dos resultados obtidos pôde ser concluído que ambos os extratos podem constituir uma alternativa no controle da população desses caramujos e na redução da esquistossomose.The turmeric is the clean rhizome at good conditions, dried and powdered of Curcuma longa L., an herbaceous plant of Zingiberaceae family. Aiming new alternatives for Schistosomiasis control, the Curcuma longa L. extracts were tested for molluscicidal activity evaluation against adult snails of Biomphalaria glabrata specie, and the toxicity (Brine Shrimp Lethality-BSL-bioassay. The oleoresin and the essential oil of turmeric were active against Artemia salina (CL50 = 80.43 and CL50 = 319.82 μg.mL-1, respectively and also active against the adult snails of Biomphalaria glabrata (CL50 = 58.3 and CL50 = 46.73 μg.mL-1, respectively. From the obtained results it was concluded that both extracts can constitute an alternative to population control of these snails and in the reduction of Schistosomiasis.

  8. Histamine Immunoreactive Elements in the Central and Peripheral Nervous Systems of the Snail, Biomphalaria spp., Intermediate Host for Schistosoma mansoni.

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    Habib, Mohamed R; Mohamed, Azza H; Osman, Gamalat Y; Sharaf El-Din, Ahmed T; Mossalem, Hanan S; Delgado, Nadia; Torres, Grace; Rolón-Martínez, Solymar; Miller, Mark W; Croll, Roger P

    2015-01-01

    Histamine appears to be an important transmitter throughout the Animal Kingdom. Gastropods, in particular, have been used in numerous studies establishing potential roles for this biogenic amine in the nervous system and showing its involvement in the generation of diverse behaviours. And yet, the distribution of histamine has only previously been described in a small number of molluscan species. The present study examined the localization of histamine-like immunoreactivity in the central and peripheral nervous systems of pulmonate snails of the genus Biomphalaria. This investigation demonstrates immunoreactive cells throughout the buccal, cerebral, pedal, left parietal and visceral ganglia, indicative of diverse regulatory functions in Biomphalaria. Immunoreactivity was also present in statocyst hair cells, supporting a role for histamine in graviception. In the periphery, dense innervation by immunoreactive fibers was observed in the anterior foot, perioral zone, and other regions of the body wall. This study thus shows that histamine is an abundant transmitter in these snails and its distribution suggest involvement in numerous neural circuits. In addition to providing novel subjects for comparative studies of histaminegic neurons in gastropods, Biomphalaria is also the major intermediate host for the digenetic trematode parasite, which causes human schistosomiasis. The study therefore provides a foundation for understanding potential roles for histamine in interactions between the snail hosts and their trematode parasites.

  9. Ionotropic Receptors Identified within the Tentacle of the Freshwater Snail Biomphalaria glabrata, an Intermediate Host of Schistosoma mansoni.

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    Di Liang

    Full Text Available Biomphalaria glabrata (B. glabrata is an air-breathing aquatic mollusc found in freshwater habitats across the Western Hemisphere. It is most well-known for its recognized capacity to act as a major intermediate host for Schistosoma mansoni, the human blood fluke parasite. Ionotropic receptors (IRs, a variant family of the ionotropic glutamate receptors (iGluR, have an evolutionary ancient function in detecting odors to initiate chemosensory signaling. In this study, we applied an array of methods towards the goal of identifying IR-like family members in B. glabrata, ultimately revealing two types, the iGluR and IR. Sequence alignment showed that three ligand-binding residues are conserved in most Biomphalaria iGluR sequences, while the IRs did exhibit a variable pattern, lacking some or all known glutamate-interactingresidues, supporting their distinct classification from the iGluRs. We show that B. glabrata contains 7 putative IRs, some of which are expressed within its chemosensory organs. To further investigate a role for the more ancient IR25a type in chemoreception, we tested its spatial distribution pattern within the snail cephalic tentacle by in situ hybridization. The presence of IR25a within presumptive sensory neurons supports a role for this receptor in olfactory processing, contributing to our understanding of the molecular pathways that are involved in Biomphalaria olfactory processing.

  10. Predation of Biomphalaria glabrata during the development of Belostoma anurum (Hemiptera, Belostomatidae Predação de Biomphalaria glabrata durante o desenvolvimento de Belostoma anunan (Hemiptera, Belostomatidae

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    M.H. Pereira

    1993-10-01

    Full Text Available Belostoma anurum was reared under laboratory conditions. Specimens were exposed to semi-natural conditions of photo period. The mortality rate was 26.3% during the post embryonic period (38.6 ± 0.7 days. During this time the average predation of Biomphalaria glabrata was of 99.0 ± 9.4 snails. The mean increment ratio of length and dry weight per instar was of 1.4 ± 0.1 and 2.8 ± 0.5, respectively. The predation by B. anurum adults can be divided into two different periods: phase I (4.8 ± 1.4 snails/day and phase II (1.8 ± 0.5 snails/day. The higher predation in phase I suggested the sexual maturation of the belostomatid.Belostoma anurum foi criada no laboratório em condição semi-natural de fotoperíodo. A taxa de mortalidade durante o período pós-embrionário (38,6 ± 0,7 dias foi de 26,3%. Durante este período a predação média de B. glabrata foi de 99,0 ± 9,4 caramujos. A média de incremento de comprimento e de peso seco por estádio ninfal foi de 1,4 ± 0,1 e 2,8 ± 0,5, respectivamente. A predação por adultos de B. anurum pode ser dividida em duas fases significativamente distintas: fase I (4,8 ± 1,4 caramujos/dia e fase II (1,8 ± 0,5 caramujos/ dia. A maior predação verificada na fase I deve-se provavelmente à maturação sexual do belostomatídeo.

  11. Hydrological stress as a limiting factor of the invasion of Limnoperna fortunei (Dunker, 1857 in the Upper Paraná River (Brazil Estresse hidrológico como fator limitante para a invasão de Limnoperna fortunei (Dunker,1857 no Alto Rio Paraná (Brasil

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    Mônica de Cássia Souza Campos

    2012-03-01

    Full Text Available Limnoperna fortunei (Dunker, 1857, is an asiatic mussel that arrived in South America in 1991. Since 2004, we have noticed that the advance of this species in the lower Paranaíba River, a tributary of the Upper Paraná River, is slow when compared to the average speed of 240 km/year in the Paraná River (middle and lower course. AIM: The goal of this work is to understand what factors are limiting the spread of L. fortunei in this stretch of the Paranaíba River. METHODS: Its occurrence and dispersion were sampled twelve times between March 2006 and November 2007 in the Paranaíba River, including the São Simão hydroelectric reservoir. Physicochemical characteristics of the water were analysed, and a Stream Length-Gradient Index calculated for the study area. RESULTS: Adult mussels were easily found attached to the hulls of barges that travel on this stretch of the Paraná-Tietê waterway and on vessels that were docked in the harbours of grain exporters located in São Simão (GO. However, no larvae or adults were found near the harbours or upstream from them at the São Simão hydroelectric reservoir. The pH and concentration of calcium and dissolved oxygen values among lotic habitats and the reservoir were similar: DO values were close to 7 mg.L-1, the average pH was near 7, average values of total Ca ranged between 4 and 6 mg.L-1 and the chlorophyll-a levels were not restrictive to the mussel. CONCLUSION: Physical and chemical water parameters show that habitats were suitable for establishment of the mussel. In addition to a low pressure of propagules, this paper proposes some hydrological variables, such as the energy of the fluvial stretches, expressed by the Stream Length-Gradient Index and changes in flow downstream of the dam as barriers to the establishment of the species, discouraging larval settlement, and decreasing survival and recruitment.Limnoperna fortunei (Dunker, 1857, é um molusco asiático que chegou na América do Sul

  12. Environmental Epidemiology of Intestinal Schistosomiasis in Uganda: Population Dynamics of Biomphalaria (Gastropoda: Planorbidae in Lake Albert and Lake Victoria with Observations on Natural Infections with Digenetic Trematodes

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    Candia Rowel

    2015-01-01

    Full Text Available This study documented the population dynamics of Biomphalaria and associated natural infections with digenetic trematodes, along the shores of Lake Albert and Lake Victoria, recording local physicochemical factors. Over a two-and-a-half-year study period with monthly sampling, physicochemical factors were measured at 12 survey sites and all freshwater snails were collected. Retained Biomphalaria were subsequently monitored in laboratory aquaria for shedding trematode cercariae, which were classified as either human infective (Schistosoma mansoni or nonhuman infective. The population dynamics of Biomphalaria differed by location and by lake and had positive relationship with pH (P<0.001 in both lakes and negative relationship with conductivity (P=0.04 in Lake Albert. Of the Biomphalaria collected in Lake Albert N=6,183, 8.9% were infected with digenetic trematodes of which 15.8% were shedding S. mansoni cercariae and 84.2% with nonhuman infective cercariae. In Lake Victoria, 2.1% of collected Biomphalaria  N=13,172 were infected with digenetic trematodes with 13.9% shedding S. mansoni cercariae, 85.7% shedding nonhuman infective cercariae, and 0.4% of infected snails shedding both types of cercariae. Upon morphological identification, species of Biomphalaria infected included B. sudanica, B. pfeifferi, and B. stanleyi in Lake Albert and B. sudanica, B. pfeifferi, and B. choanomphala in Lake Victoria. The study found the physicochemical factors that influenced Biomphalaria population and infections. The number and extent of snails shedding S. mansoni cercariae illustrate the high risk of transmission within these lake settings. For better control of this disease, greater effort should be placed on reducing environmental contamination by improvement of local water sanitation and hygiene.

  13. Environmental Epidemiology of Intestinal Schistosomiasis in Uganda: Population Dynamics of Biomphalaria (Gastropoda: Planorbidae) in Lake Albert and Lake Victoria with Observations on Natural Infections with Digenetic Trematodes

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    Rowel, Candia; Fred, Besigye; Sousa-Figueiredo, Jose C.; Kabatereine, Narcis B.; Stothard, J. Russell

    2015-01-01

    This study documented the population dynamics of Biomphalaria and associated natural infections with digenetic trematodes, along the shores of Lake Albert and Lake Victoria, recording local physicochemical factors. Over a two-and-a-half-year study period with monthly sampling, physicochemical factors were measured at 12 survey sites and all freshwater snails were collected. Retained Biomphalaria were subsequently monitored in laboratory aquaria for shedding trematode cercariae, which were classified as either human infective (Schistosoma mansoni) or nonhuman infective. The population dynamics of Biomphalaria differed by location and by lake and had positive relationship with pH (P < 0.001) in both lakes and negative relationship with conductivity (P = 0.04) in Lake Albert. Of the Biomphalaria collected in Lake Albert (N = 6,183), 8.9% were infected with digenetic trematodes of which 15.8% were shedding S. mansoni cercariae and 84.2% with nonhuman infective cercariae. In Lake Victoria, 2.1% of collected Biomphalaria  (N = 13,172) were infected with digenetic trematodes with 13.9% shedding S. mansoni cercariae, 85.7% shedding nonhuman infective cercariae, and 0.4% of infected snails shedding both types of cercariae. Upon morphological identification, species of Biomphalaria infected included B. sudanica, B. pfeifferi, and B. stanleyi in Lake Albert and B. sudanica, B. pfeifferi, and B. choanomphala in Lake Victoria. The study found the physicochemical factors that influenced Biomphalaria population and infections. The number and extent of snails shedding S. mansoni cercariae illustrate the high risk of transmission within these lake settings. For better control of this disease, greater effort should be placed on reducing environmental contamination by improvement of local water sanitation and hygiene. PMID:25705680

  14. Molluscicidal and ovicidal activities of plant extracts of the Piperaceae on Biomphalaria glabrata (Say, 1818).

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    Rapado, L N; Nakano, E; Ohlweiler, F P; Kato, M J; Yamaguchi, L F; Pereira, C A B; Kawano, T

    2011-03-01

    Schistosomiasis is a tropical disease caused by Schistosoma and occurs in 54 countries, mainly in South America, the Caribbean region, Africa and the eastern Mediterranean. Currently, 5 to 6 million Brazilian people are infected and 30,000 are under infection risk. Typical of poor regions, this disease is associated with the lack of basic sanitation and very frequently to the use of contaminated water in agriculture, housework and leisure. One of the most efficient methods of controlling the disease is application of molluscicides to eliminate or to reduce the population of the intermediate host snail Biomphalaria glabrata. Studies on molluscicidal activity of plant extracts have been stimulated by issues such as environmental preservation, high cost and recurrent resistance of snails to synthetic molluscicides. The aim of this study was to determine the molluscicide action of extracts from Piperaceae species on adult and embryonic stages of B. glabrata. Fifteen extracts from 13 Piperaceae species were obtained from stems, leaves and roots. Toxicity of extracts was evaluated against snails at two different concentrations (500 and 100 ppm) and those causing 100% mortality at 100 ppm concentration were selected to obtain the LC₉₀ (lethal concentration of 90% mortality). Piper aduncum, P. crassinervium, P. cuyabanum, P. diospyrifolium and P. hostmannianum gave 100% mortality of adult snails at concentrations ranging from 10 to 60 ppm. These extracts were also assayed on embryonic stages of B. glabrata and those from P. cuyabanum and P. hostmannianum showed 100% ovicidal action at 20 ppm.

  15. Larvicidal Activity against Aedes aegypti and Molluscicidal Activity against Biomphalaria glabrata of Brazilian Marine Algae

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    Guedes, Elíca Amara Cecília; de Carvalho, Cenira M.; Ribeiro Junior, Karlos Antonio Lisboa; Lisboa Ribeiro, Thyago Fernando; de Barros, Lurdiana Dayse; de Lima, Maria Raquel Ferreira; Prado Moura, Flávia de Barros; Goulart Sant'Ana, Antônio Euzebio

    2014-01-01

    This study investigated the biological activities of five benthic marine algae collected from Northeastern Region of Brazil. The tested activities included larvicidal activity against Aedes aegypti, molluscicidal activity against Biomphalaria glabrata, and toxicity against Artemia salina. Extracts of Ulva lactuca (Chlorophyta), Padina gymnospora, Sargassum vulgare (Phaeophyta), Hypnea musciformis, and Digenea simplex (Rhodophyta) were prepared using different solvents of increasing polarity, including dichloromethane, methanol, ethanol, and water. Of the extracts screened, the dichloromethane extracts of H. musciformis and P. gymnospora exhibited the highest activities and were subjected to bioassay-guided fractionation in hexane and chloroform. The chloroform fractions of the P. gymnospora and H. musciformis extracts showed molluscicidal activity at values below 40 μg·mL−1 (11.1460 μg·mL−1 and 25.8689 μg·mL−1, resp.), and the chloroform and hexane fractions of P. gymnospora showed larvicidal activity at values below 40 μg·mL−1 (29.018 μg·mL−1 and 17.230 μg·mL−1, resp.). The crude extracts were not toxic to A. salina, whereas the chloroform and hexane fractions of P. gymnospora (788.277 μg·mL−1 and 706.990 μg·mL−1) showed moderate toxicity, indicating that the toxic compounds present in these algae are nonpolar. PMID:24688787

  16. Extra-cellular matrix changes in Schistosoma mansoni-infected Biomphalaria glabrata

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    Borges Claudia Maria da Cunha

    2003-01-01

    Full Text Available Reactivity of snails against parasites exhibits a primitive focal reaction, with encapsulation, phagocytosis and destruction of parasite larvae by macrophage-like cells - the hemocytes. This reaction mimics granulomatous inflammation seen in higher animals. However, different from the latter, little is known about the participation of extra-cellular matrix in such snail defense reactions. Normal and Schistosoma mansoni-infected Biomphalaria glabrata of different strains were submitted to cytological, histological, ultrastructural and biochemical methods in order to investigate the behavior of extra-cellular tissues at the site of anti-parasite reactions. In spite of the presence of two cell-types in peripheral hemolymph, only one cell-type was present at the sites of tissue reactions. Although pre-existent collagen and elastic fibers and microfibrils sometimes appeared slightly compressed around focal reactions, no evidences of duplication, synthesis or deposition of connective-tissue extra-cellular components were observed within or around the zones of reactive cell accumulations. Thus, tissue reactions against S. mansoni in the snail B. glabrata appeared exclusively dependent on one specific population of hemocytes.

  17. A novel bacterial pathogen of Biomphalaria glabrata: a potential weapon for schistosomiasis control?

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    David Duval

    2015-02-01

    Full Text Available Schistosomiasis is the second-most widespread tropical parasitic disease after malaria. Various research strategies and treatment programs for achieving the objective of eradicating schistosomiasis within a decade have been recommended and supported by the World Health Organization. One of these approaches is based on the control of snail vectors in endemic areas. Previous field studies have shown that competitor or predator introduction can reduce snail numbers, but no systematic investigation has ever been conducted to identify snail microbial pathogens and evaluate their molluscicidal effects.In populations of Biomphalaria glabrata snails experiencing high mortalities, white nodules were visible on snail bodies. Infectious agents were isolated from such nodules. Only one type of bacteria, identified as a new species of Paenibacillus named Candidatus Paenibacillus glabratella, was found, and was shown to be closely related to P. alvei through 16S and Rpob DNA analysis. Histopathological examination showed extensive bacterial infiltration leading to overall tissue disorganization. Exposure of healthy snails to Paenibacillus-infected snails caused massive mortality. Moreover, eggs laid by infected snails were also infected, decreasing hatching but without apparent effects on spawning. Embryonic lethality was correlated with the presence of pathogenic bacteria in eggs.This is the first account of a novel Paenibacillus strain, Ca. Paenibacillus glabratella, as a snail microbial pathogen. Since this strain affects both adult and embryonic stages and causes significant mortality, it may hold promise as a biocontrol agent to limit schistosomiasis transmission in the field.

  18. Steroid Androgen Exposure during Development Has No Effect on Reproductive Physiology of Biomphalaria glabrata.

    Science.gov (United States)

    Kaur, Satwant; Baynes, Alice; Lockyer, Anne E; Routledge, Edwin J; Jones, Catherine S; Noble, Leslie R; Jobling, Susan

    2016-01-01

    Gastropod mollusks have been proposed as alternative models for male reproductive toxicity testing, due to similarities in their reproductive anatomy compared to mammals, together with evidence that endocrine disrupting chemicals can cause effects in some mollusks analogous to those seen in mammals. To test this hypothesis, we used the freshwater pulmonate snail, Biomphalaria glabrata, for which various genetic tools and a draft genome have recently become available, to investigate the effects of two steroid androgens on the development of mollusk secondary sexual organs. Here we present the results of exposures to two potent androgens, the vertebrate steroid; 5α-dihydrotestosterone (DHT) and the pharmaceutical anabolic steroid; 17α-methyltestosterone (MT), under continuous flow-through conditions throughout embryonic development and up to sexual maturity. Secondary sexual gland morphology, histopathology and differential gene expression analysis were used to determine whether steroid androgens stimulated or inhibited organ development. No significant differences between tissues from control and exposed snails were identified, suggesting that these androgens elicited no biologically detectable response normally associated with exposure to androgens in vertebrate model systems. Identifying no effect of androgens in this mollusk is significant, not only in the context of the suitability of mollusks as alternative model organisms for testing vertebrate androgen receptor agonists but also, if applicable to other similar mollusks, in terms of the likely impacts of androgens and anti-androgenic pollutants present in the aquatic environment.

  19. Steroid Androgen Exposure during Development Has No Effect on Reproductive Physiology of Biomphalaria glabrata.

    Directory of Open Access Journals (Sweden)

    Satwant Kaur

    Full Text Available Gastropod mollusks have been proposed as alternative models for male reproductive toxicity testing, due to similarities in their reproductive anatomy compared to mammals, together with evidence that endocrine disrupting chemicals can cause effects in some mollusks analogous to those seen in mammals. To test this hypothesis, we used the freshwater pulmonate snail, Biomphalaria glabrata, for which various genetic tools and a draft genome have recently become available, to investigate the effects of two steroid androgens on the development of mollusk secondary sexual organs. Here we present the results of exposures to two potent androgens, the vertebrate steroid; 5α-dihydrotestosterone (DHT and the pharmaceutical anabolic steroid; 17α-methyltestosterone (MT, under continuous flow-through conditions throughout embryonic development and up to sexual maturity. Secondary sexual gland morphology, histopathology and differential gene expression analysis were used to determine whether steroid androgens stimulated or inhibited organ development. No significant differences between tissues from control and exposed snails were identified, suggesting that these androgens elicited no biologically detectable response normally associated with exposure to androgens in vertebrate model systems. Identifying no effect of androgens in this mollusk is significant, not only in the context of the suitability of mollusks as alternative model organisms for testing vertebrate androgen receptor agonists but also, if applicable to other similar mollusks, in terms of the likely impacts of androgens and anti-androgenic pollutants present in the aquatic environment.

  20. Influence of experimental illumination and seasonal variation on crossbreending mating in the snail Biomphalaria Glabrata

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    F. Pimentel-Souza

    1988-03-01

    Full Text Available The crossbreeding activities of the Schistosoma mansoni vector snail Biomphalaria glabrata were counted in a laboratory aquarium throughout the year under two regimes of 12h light: 12h dark from 7 A., M. to 10 P. M. Mating increased significantly in Authmn and Winter and just missed a significant inverse correlation with temperature and a direct one with locomotion. Other similar experiments were carried out to compare mating under various ilumination conditions in complete daily cycle measurements. Mating counts decreased under the regimes which submited snail to a total exposure of 12h light and 12 dark during a daily cycle in the following sequence: 12h light: 12h dark alternating hourly with light gradient, 12h light: 12h dark, 1h light: 1h dark and 12h dark: 12h light. Under two constant illuminations, the mating scored less than under the previous conditions, except under 12h light. Under darkeness the mating count was lower than light conditions. There was no way to differentiate the night and day rhythms of mating on different days in each regime, except for mating under 12h light: 12 dark alternating with light gradient, constant dark and 12h dark: 12h light conditions. Mating increased in certain light and temperature conditions, in wich the intensities, should have an optimum value.

  1. Effects of high dose rate gamma radiation on survival and reproduction of Biomphalaria glabrata

    Energy Technology Data Exchange (ETDEWEB)

    Cantinha, Rebeca S.; Nakano, Eliana [Instituto Butantan, Sao Paulo, SP (Brazil). Lab. de Parasitologia], e-mail: rebecanuclear@gmail.com, e-mail: eliananakano@butantan.gov.br; Borrely, Sueli I. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil). Centro de Tecnologia das Radiacoes], e-mail: sborrely@ipen.br; Amaral, Ademir; Melo, Ana M.M.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia (GERAR)], e-mail: amaral@ufpe.br; Silva, Luanna R.S. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia. Lab. de Radiobiologia], e-mail: amdemelo@hotmail.com, e-mail: luannaribeiro_lua@hotmail.com

    2009-07-01

    Ionizing radiations are known as mutagenic agents, causing lethality and infertility. This characteristic has motivated its application on animal biological control. In this context, the freshwater snail Biomphalaria glabrata can be considered an excellent experimental model to study effects of ionizing radiations on lethality and reproduction. This work was designed to evaluate effects of {sup 60}Co gamma radiation at high dose rate (10.04 kGy/h) on B. glabrata. For this purpose, adult snails were selected and exposed to doses ranging from 20 to 100 Gy, with 10 Gy intervals; one group was kept as control. There was not effect of dose rate in the lethality of gamma radiation; the value of 64,3 Gy of LD{sub 50} obtained in our study was similar to that obtained by other authors with low dose rates. Nevertheless, our data suggest that there was a dose rate effect in the reproduction. On all dose levels, radiation improved the production of embryos for all exposed individuals. However, viability indexes were below 6% and, even 65 days after irradiation, fertility was not recovered. These results are not in agreement with other studies using low dose rates. Lethality was obtained in all groups irradiated, and the highest doses presented percentiles of dead animals above 50%. The results demonstrated that doses of 20 and 30 Gy were ideal for population control of B. glabrata. Further studies are needed; nevertheless, this research evidenced great potential of high dose rate gamma radiation on B. glabrata reproductive control. (author)

  2. Toxicity of some glucose/mannose-binding lectins to Biomphalaria glabrata and Artemia salina.

    Science.gov (United States)

    dos Santos, Aldenir Feitosa; Cavada, Benildo Sousa; da Rocha, Bruno Anderson Matias; do Nascimento, Kyria Santiago; Sant'Ana, Antônio Euzébio Goulart

    2010-01-01

    Schistosomiasis or bilharzia, which affects millions of people living in Africa, Asia and Latin America, is closely associated with certain species of aquatic snails. One way of attacking the disease is to eradicate the host snails. Molluscicidal activities of natural compounds are especially important in the widespread control of this tropical disease. As part of our search for natural compounds with molluscicidal properties for the vector control of schistosomiasis, we are now evaluating for the first time the toxicity of the plant lectins from Canavalia brasiliensis (ConBr), Cratylia floribunda (CFL), Dioclea guianensis (Dgui), Dioclea grandiflora (DGL) and Dioclea virgata (Dvir) to Biomphalaria glabrata Say and Artemia salina Leach. Results indicate that all the samples were toxic to A. salina Leach, some of them with values of lethal concentration that kills 90% of the population (LC(90))<10 microg mL(-1). They are also active against B. glabrata Say, killing 100% of adult snails, at a concentration of 50 microg mL(-1). The lectins CFL and Dgui possess properties lethal to mollusks, with values of LC(90)=50.3 microg mL(-1) and LC(90)=41.0 microg mL(-1), respectively.

  3. Profile of organic acid concentrations in the digestive gland and hemolymph of Biomphalaria glabrata under estivation

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    José Clecildo Barreto Bezerra

    1999-11-01

    Full Text Available Using high performance liquid chromatography (HPLC analysis it was possible to determine simultaneously the concentration of organic acids (pyruvate, lactate, succinate, fumarate, malate, acetate, propionate, acetoacetate, and ß-hydroxybutyrate in the digestive gland and the extracellular concentration of these same acids in the hemolymph of estivating Biomphalaria glabrata, the intermediate host of Schistosoma mansoni. After a 7 day period of estivation, there was a significant increase in the tissue levels of lactate, succinate, malate and acetate compared to non-estivating snails. After 14 days of estivation, the levels of lactate and acetate were also significantly elevated. The hemolymph concentrations of pyruvate and acetate increased significantly after 7 days and acetate concentrations continued to be significantly increased up to 14 days of estivation. The other organic acids studied, such as ketone body acetoacetate and ß-hydroxybutyrate or the volatile acid propionate, did not accumulate. Their tissue concentrations, however, increased on the 7th day of estivation and reached normal levels within two weeks of estivation for some of them. One should take into consideration how the reduction in metabolism can be handled under aerobic conditions, and what role anaerobic pathways may play in both energy formation and redox balance processes.

  4. H+ channels in embryonic Biomphalaria glabrata cell membranes: Putative roles in snail host-schistosome interactions

    Science.gov (United States)

    Wright, Brandon J.; Bickham-Wright, Utibe; Yoshino, Timothy P.; Jackson, Meyer B.

    2017-01-01

    The human blood fluke Schistosoma mansoni causes intestinal schistosomiasis, a widespread neglected tropical disease. Infection of freshwater snails Biomphalaria spp. is an essential step in the transmission of S. mansoni to humans, although the physiological interactions between the parasite and its obligate snail host that determine success or failure are still poorly understood. In the present study, the B. glabrata embryonic (Bge) cell line, a widely used in vitro model for hemocyte-like activity, was used to investigate membrane properties, and assess the impact of larval transformation proteins (LTP) on identified ion channels. Whole-cell patch clamp recordings from Bge cells demonstrated that a Zn2+-sensitive H+ channel serves as the dominant plasma membrane conductance. Moreover, treatment of Bge cells with Zn2+ significantly inhibited an otherwise robust production of reactive oxygen species (ROS), thus implicating H+ channels in the regulation of this immune function. A heat-sensitive component of LTP appears to target H+ channels, enhancing Bge cell H+ current over 2-fold. Both Bge cells and B. glabrata hemocytes express mRNA encoding a hydrogen voltage-gated channel 1 (HVCN1)-like protein, although its function in hemocytes remains to be determined. This study is the first to identify and characterize an H+ channel in non-neuronal cells of freshwater molluscs. Importantly, the involvement of these channels in ROS production and their modulation by LTP suggest that these channels may function in immune defense responses against larval S. mansoni. PMID:28319196

  5. New scope on the relationship between rotifers and Biomphalaria alexandrina snails

    Institute of Scientific and Technical Information of China (English)

    Shereen Farouk Mossallam; Eglal Ibrahim Amer; Iman Fathy Abou-El-Naga

    2013-01-01

    Objective: To investigate the effect of rotifer internalization into snail tissue on the development of schistosomes. Methods:Susceptible laboratory-bred Biomphalaria alexandrina (B. alexandrina) snails were exposed to lab-maintained rotifers; Philodina spp., two weeks before and after being infected with Schistosoma mansoni (S. mansoni) miracidia. The consequent histopathological impact on snail tissues and cercarial biology were investigated before and after emergence from snails. Results:Contamination of B. alexandrina snails with philodina, two weeks before miracidial exposure, was found to hinder the preliminary development of S. mansoni cercariae inside the snail tissues. Furthermore, when snails were contaminated with rotifers two weeks post miracidial exposure; growth of already established cercariae was found to be retarded. The consequent influence of internalized rotifers within the snail tissue was clearly reflected on cercarial emergence, activity and infectivity along the four weeks duration of shedding. In the present study, comparison of snail histopathological findings and altered cercarial biology observed between the experimental and control groups indicated that the rotifers may have affected the levels of snail's energy reservoirs, which eventually was found to have had an adverse impact on reproduction, growth and survival of the parasite within the snail host, coupled with its performance outside the snail. Conclusions:In future biological control strategies of schistosomiasis, ritifers should be considered as a parasitic scourge of humanity.

  6. Steroid Androgen Exposure during Development Has No Effect on Reproductive Physiology of Biomphalaria glabrata

    Science.gov (United States)

    Lockyer, Anne E.; Routledge, Edwin J.; Jones, Catherine S.; Noble, Leslie R.; Jobling, Susan

    2016-01-01

    Gastropod mollusks have been proposed as alternative models for male reproductive toxicity testing, due to similarities in their reproductive anatomy compared to mammals, together with evidence that endocrine disrupting chemicals can cause effects in some mollusks analogous to those seen in mammals. To test this hypothesis, we used the freshwater pulmonate snail, Biomphalaria glabrata, for which various genetic tools and a draft genome have recently become available, to investigate the effects of two steroid androgens on the development of mollusk secondary sexual organs. Here we present the results of exposures to two potent androgens, the vertebrate steroid; 5α-dihydrotestosterone (DHT) and the pharmaceutical anabolic steroid; 17α-methyltestosterone (MT), under continuous flow-through conditions throughout embryonic development and up to sexual maturity. Secondary sexual gland morphology, histopathology and differential gene expression analysis were used to determine whether steroid androgens stimulated or inhibited organ development. No significant differences between tissues from control and exposed snails were identified, suggesting that these androgens elicited no biologically detectable response normally associated with exposure to androgens in vertebrate model systems. Identifying no effect of androgens in this mollusk is significant, not only in the context of the suitability of mollusks as alternative model organisms for testing vertebrate androgen receptor agonists but also, if applicable to other similar mollusks, in terms of the likely impacts of androgens and anti-androgenic pollutants present in the aquatic environment. PMID:27448327

  7. Parental transfer of the antimicrobial protein LBP/BPI protects Biomphalaria glabrata eggs against oomycete infections.

    Directory of Open Access Journals (Sweden)

    Olga Lucia Baron

    Full Text Available Vertebrate females transfer antibodies via the placenta, colostrum and milk or via the egg yolk to protect their immunologically immature offspring against pathogens. This evolutionarily important transfer of immunity is poorly documented in invertebrates and basic questions remain regarding the nature and extent of parental protection of offspring. In this study, we show that a lipopolysaccharide binding protein/bactericidal permeability increasing protein family member from the invertebrate Biomphalaria glabrata (BgLBP/BPI1 is massively loaded into the eggs of this freshwater snail. Native and recombinant proteins displayed conserved LPS-binding, antibacterial and membrane permeabilizing activities. A broad screening of various pathogens revealed a previously unknown biocidal activity of the protein against pathogenic water molds (oomycetes, which is conserved in human BPI. RNAi-dependent silencing of LBP/BPI in the parent snails resulted in a significant reduction of reproductive success and extensive death of eggs through oomycete infections. This work provides the first functional evidence that a LBP/BPI is involved in the parental immune protection of invertebrate offspring and reveals a novel and conserved biocidal activity for LBP/BPI family members.

  8. Spatial and seasonal trends of a natural population of Biomphalaria occidentalis in northeastern Argentina

    Directory of Open Access Journals (Sweden)

    Alejandra Rumi

    1992-06-01

    Full Text Available This study aims to analyze the age of a population of Biomphalaria occidentalis on a pound of Riachuelo river basin, wich is one of the three most important Middle Paraná river affluents in Corrientes province. Samples were drawn from three stations, were spatial and temporal numerical variations of the snail, as well as its relation with different environmental parameters, mainly temperature, rainfall, pH and conductivity, were analyzed. Snail abundance is given in number of individuals/hour. The differences between the three sampling stations, estimated by nonparametric tests, was nonsignificant. A relative scale to the greatest shell diameter was employed to build the age pyramids. Temporal fluctuations of snail abundance correlated negatively with the highest monthly accumulated temperatures (P < 0.05. Although different floristic compositions were observed at the three stations, no significant numerical variations were detected in B. occidentalis spatial distribution. Reproductive activity took place between March-April and November with overlapping cohort system. During summer (December-Febuary mortality increased along with temperature and reproductive activity was not evident.

  9. Polyethyleneimine (PEI mediated siRNA gene silencing in the Schistosoma mansoni snail host, Biomphalaria glabrata.

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    Matty Knight

    2011-07-01

    Full Text Available An in vivo, non-invasive technique for gene silencing by RNA interference (RNAi in the snail, Biomphalaria glabrata, has been developed using cationic polymer polyethyleneimine (PEI mediated delivery of long double-stranded (ds and small interfering (si RNA. Cellular delivery was evaluated and optimized by using a 'mock' fluorescent siRNA. Subsequently, we used the method to suppress expression of Cathepsin B (CathB with either the corresponding siRNA or dsRNA of this transcript. In addition, the knockdown of peroxiredoxin (Prx at both RNA and protein levels was achieved with the PEI-mediated soaking method. B. glabrata is an important snail host for the transmission of the parasitic digenean platyhelminth, Schistosoma mansoni that causes schistosomiasis in the neotropics. Progress is being made to realize the genome sequence of the snail and to uncover gene expression profiles and cellular pathways that enable the snail to either prevent or sustain an infection. Using PEI complexes, a convenient soaking method has been developed, enabling functional gene knockdown studies with either dsRNA or siRNA. The protocol developed offers a first whole organism method for host-parasite gene function studies needed to identify key mechanisms required for parasite development in the snail host, which ultimately are needed as points for disrupting this parasite mediated disease.

  10. Molecular identification of symbionts from the pulmonate snail Biomphalaria glabrata in Brazil.

    Science.gov (United States)

    Hertel, Lynn A; Barbosa, Contança S; Santos, Ricardo A A L; Loker, Eric S

    2004-08-01

    The icthyosporean, Capsaspora owczarzaki, a known predator of Schistosoma mansoni sporocysts in vitro, is more prevalent in laboratory-reared strains of the intermediate snail host, Biomphalaria glabrata resistant to S. mansoni, than from the susceptible M line strain. We examined whether B. glabrata resistant to the NIH-PR-1 strain of S. mansoni from 2 regions in Brazil were also host to C. owczarzaki. Symbiont presence was examined using hemolymph culturing and nested polymerase chain reaction of snail genomic DNA with primers designed to specifically amplify sequences from relatives of the Icthyosporea. All B. glabrata of the resistant Salvador strain from the laboratory of Dr. Lobato Paraense in Rio de Janeiro, Brazil (n = 46) tested negative for symbionts. Three of 18 semiresistant 10-R2 B. glabrata from the laboratory of Dr. Barbosa in Recife, Brazil tested positive for C. owczarzaki. Another icthyosporean, Anurofeca sp., was identified from 1, 10-R2 snail and from 2 of 12 field-collected B. glabrata from Praia do Forte Orange, Ilha de Itamaracá. Snails from 2 other sites, Hotel Colibri, Pontezinha and Praia do Sossego, Ilha de Itamaracá, were negative for Anurofeca. Two genera of ciliates were also identified. Paruroleptus sp. was found in 4, 10-R2 snails and Trichodina sp. was identified in 2 field-collected snails from Praia do Forte Orange and Praia do Sossego.

  11. Influence of gamma radiation on the levels of polyphenols and lethality of ethanol extracts of Anacardium occidentale Linn., against Biomphalaria glabrata; Influencia da radiacao gama na acao moluscicida de extratos de cajueiro em Biomphalaria glabrata

    Energy Technology Data Exchange (ETDEWEB)

    Santos, G.H.F.; Silva, E.B., E-mail: santosghf@hotmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Energia Nuclear. Grupo de Radioprotecao e Radioecologia; Melo, A.M.M.A.; Lima, C.S.A [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica; Amorim, E.L.C.; Peixoto Sobrinho, T.J.S. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Farmacia

    2013-08-15

    Plant materials rich in phenolic compounds, such as Anacardium occidentale Linn., Have been used as alternatives to synthetic pesticides in Biomphalaria glabrata control programs, intermediate host of Schistosoma mansoni. Studies show that ionizing radiation can influence the content of phenolic compounds and thus their biological actions. The aim of this study was to evaluate the influence of gamma radiation of {sup 60}Co in polyphenol composition of hydroalcoholic extracts of bark and leaves of A. occidentale and evaluate the toxicity of these extracts to embryos and adults of B. glabrata. To achieve this goal this, the extracts were irradiated at 10 kGy, the controls being maintained from 0 kGy and positive (CaCO{sub 3}) and negative (H{sub 2}O). We quantified the total phenols by the Folin-Ciocalteau and tannins by precipitation of casein. Extracts were used at a concentration of 100 mg/L. The results showed that the radiation caused the changes to the leaves, the percentage of polyphenols and tannins, and the percentage of lethality in embryos and adults Biomphalaria glabrata, these percentages being: 13 ± 5 (0 kGy) and 27 ± 2.5 (10 kGy), and 36.67 ± 5.77 (0 kGy), and 56.67 ± 5.77 (10 kGy), respectively. Gamma radiation caused significant changes in the levels of polyphenols in the extracts of leaves of Anacardium ocidentale Linn., translated by the increased toxicity of this extract against embryos and adults of Biomphalaria glabrata. This indicates that gamma radiation can be used as an agent potentiating the toxicity of plant extracts on the alternate use of these materials as molluscicides. (author)

  12. Estudo sobre a cópula interespecífica entre moluscos planorbídeos Biomphalaria glabrata e B. tenagophila Inter-specific mating between planorbid snails Biomphalaria glabrata and B. tenagophila

    Directory of Open Access Journals (Sweden)

    Luiz A. Magalhães

    1973-09-01

    Full Text Available Foi estudada a freqüência da cópula interespecífica entre espécimes de Biomphalaria glabrata e B. tenagophila. Os resultados da experiência levaram a conclusão de que há preferência pela cópula intraespecífica, ocorrendo, contudo, cópulas interespecíficas.An experiment on the inter-specific mating of B. glabrata and B. tenagophila snails was related. The results led to conclude that the snails prefer intra-specific mates, even though inter-specific ones occur.

  13. 马氏珠母贝饥饿补偿生长的初步研究%Preliminary study on compensatory growth in pearl oyster Pinctada martensi Dunker,following starvation

    Institute of Scientific and Technical Information of China (English)

    何毛贤; 袁涛; 黄良民

    2010-01-01

    采取饥饿处理时间不等(3、6、9和12d)、但总持续时间相等的方法研究马氏珠母贝Pinctada martensi (Dunker)稚贝在饥饿处理后的生长和存活.结果表明,S12组(饥饿12d)的存活率最低,恢复期的壳长和体重最小,表明饥饿强度大会对其生长和存活造成较大的影响;饥饿处理后的稚贝都表现出补偿生长现象,S9组(饥饿9d)的特定生长率最高,S3组(饥饿3d)的最低,但饥饿组间的差异不明显,其壳长和体重大小排列为S3>S6>S9>S12,恢复期延长,其生长恢复到正常水平.

  14. 青海省不同产地秦艽花中獐牙菜苷和异荭草苷含量的HPLC分析%Content analysis of sweroside and isoorientin in Gentiana straminea flower from different locations of Qinghai Province by HPLC

    Institute of Scientific and Technical Information of China (English)

    张兴旺; 陈晨; 陶燕铎; 梅丽娟; 邵赟

    2010-01-01

    @@ 秦艽花为龙胆科(Gentianaceae)植物麻花秦艽(Gentiana straminea Maxim.)的干燥花,藏药名为"解吉嘎保",为常用藏药材之一,具有清热解毒的作用,可用于治疗胃肠炎、肝炎及胆囊炎等症[1].

  15. Estudo quantitativo de metais presentes na hemolinfa de Biomphalaria glabrata (Gastropoda, infectadas e não infectadas com Schistosoma mansoni Quantitative study of metal present in the hemolymph of Biomphalaria glabrata (Gastropoda, infected and uninfected with Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Marco Antonio Vasconcelos Santos

    2005-04-01

    Full Text Available Inicialmente, desenvolveu-se um estudo para quantificar e comparar as concentrações de alguns metais presentes em duas amostras de hemolinfa do caramujo Biomphalaria glabrata (infectados e não-infectados com Schistosoma mansoni. A espectrometria de emissão óptica com fonte de plasma induzido (ICP-OES, foi utilizada para analisar os metais nas duas amostras. Os metais estudados foram: alumínio, cálcio, cádmio, cobalto, cromo, cobre, ferro, potássio, magnésio, manganês, chumbo e zinco. Os resultados mostram que, a princípio, os metais não são fatores determinantes no processo de defesa desses organismos contra este parasita, quando presente nos seus tecidos.We conducted a preliminary study to quantify and compare two concentrations of the same metals present in the hemolymph of snail Biomphalaria glabrata. In this context, we used Induction Coupled Plasma Optical Emission Spectroscopy technique (ICP-OES, to analyze the metals in the two samples (snails infected and not infected with Schistosoma mansoni. The metals studied were: aluminum, calcium, cadmium, cobalt, chromium, copper, iron, potassium, magnesium, manganese, lead and zinc. Preliminary results showed that such metals are not involved in the defense of these organisms against the parasite, when present in their tissues.

  16. Distribuição de Biomphalaria glabrata (Say, 1818 (Pulmonata, Planorbidae no Estado de São Paulo, Brasil Notes on the distribution of Biomphalaria glabrata (Say, 1818 (Pulmonata, Planorbidae in the S. Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    Horacio Manuel Santana Teles

    1987-12-01

    Full Text Available São apresentadas informações atualizadas sobre a distribuição geográfcia de Biomphalaria glabrata (Say, 1818 no Estado de São Paulo (Brasil, em razão do importante papel que tal espécie de planorbídeo desempenha na epidemiologia da esquistossomose mansônica. Registrou-se que a maior área colonizada por B. glabrata corresponde à região abrangida pelos municípios dos limites oeste-sudoeste do Estado, enquadrada na bacia hidrográfica do Rio Paranapanema. São comentados os prováveis mecanismos envolvidos na dispersão do caramujo.It is reported the present distribution of Biomphalaria glabrata (Say, 1818 in the S. Paulo State. The presence of this intermediate host of schistosomiasis is at the present time recorded in 27 municipalities. This snail had been identified as the most important transmissor of the disease in several places in Brazil. The probable dispersion mechanisms involved in the distribution of the snail are commented on.

  17. Effect of cadmium, lead and arsenic on the oviposition, hatching and embryonic survival of Biomphalaria glabrata

    Energy Technology Data Exchange (ETDEWEB)

    Ansaldo, Martin [Instituto Antartico Argentino, Direccion Nacional del Antartico, Cerrito 1248, (1010) Buenos Aires (Argentina)], E-mail: tincho@qb.fcen.uba.ar; Nahabedian, Daniel E. [Departamento de Quimica Biologica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, (1428), Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (Argentina); Di Fonzo, Carla [Departamento de Quimica Biologica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, (1428), Buenos Aires (Argentina); Wider, Eva A. [Departamento de Quimica Biologica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, (1428), Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (Argentina)

    2009-03-01

    Biomphalaria glabrata is a widespread freshwater gastropod mollusc. The easy aquaculture of these organisms allow its use as an accessible tool for contamination bioassays. B. glabrata showed marked metabolic responses when exposed to cadmium, lead and arsenic. Those responses could also affect the reproduction of the snails. Taking into account this hypothesis, B. glabrata were exposed for 96 h (acute laboratory bioassays) to different concentrations of cadmium (0.1, 0.05 and 0 mg/L), lead (0.5, 0.1, 0.05 and 0 mg/L) and arsenic (0.5, 0.1, 0.05 and 0 mg/L). Snails were removed from the aquaria while eggs were left in the same contaminant concentrations. The effect of the assayed toxicants on snail reproduction was registered as the alterations of the total number of laid eggs (TNLE), hatching time and embryonic survival. At 0.10 mg/L cadmium significantly decreased the TNLE (p < 0.05) and no embryos survived. The lowest assayed level (0.05 mg/L) of cadmium, delayed the hatching time twice when it was compared with the control group (p < 0.01). Lead decreased the TNLE at 0.5 mg/L level (p < 0.01). The other assayed doses (0.05 and 0.10 mg/L) also decreased embryonic survival significantly (p < 0.05 and p < 0.01 respectively) and extended twice the time to hatching (p < 0.01). The 0.50 mg/L level killed all embryos. Arsenic at all studied concentrations decreased the TNLE (p < 0.05) while the hatching time was increased by 50%. Embryo survival only decreased at the highest level (0.5 mg/L) of arsenic assayed. In summary, the acute exposure (96 h) to cadmium lead and arsenic, altered the reproduction of B. glabrata, modifying the TNLE, hatching time and embryonic survival.

  18. Assessment of toxicity of Moringa oleifera flower extract to Biomphalaria glabrata, Schistosoma mansoni and Artemia salina.

    Science.gov (United States)

    Rocha-Filho, Cláudio A A; Albuquerque, Lidiane P; Silva, Luanna R S; Silva, Patrícia C B; Coelho, Luana C B B; Navarro, Daniela M A F; Albuquerque, Monica C P A; Melo, Ana Maria M A; Napoleão, Thiago H; Pontual, Emmanuel V; Paiva, Patrícia M G

    2015-08-01

    This study reports the effect of an aqueous extract from Moringa oleifera Lam. flowers on Biomphalaria glabrata embryos and adults and on Schistosoma mansoni adult worms. The extract contains tannins, saponins, flavones, flavonols, xanthones, and trypsin inhibitor activity. The toxicity of the extract on Artemia salina larvae was also investigated to determine the safety of its use for schistosomiasis control. After incubation for 24h, the flower extract significantly (p<0.05) delayed the development of B. glabrata embryos and promoted mortality of adult snails (LC50: 2.37±0.5mgmL(-1)). Furthermore, treatment with the extract disrupted the development of embryos generated by snails, with most of them remaining in the blastula stage while control embryos were already in the gastrula stage. Flower extract killed A. salina larvae with a LC50 value (0.2±0.015mgmL(-1)) lower than that determined for snails. A small reduction (17%) in molluscicidal activity was detected when flower extract (2.37mgmL(-1)) was exposed to tropical environmental conditions (UVI index ranging from 1 to 14, temperature from 25 to 30°C, and 65% relative humidity). Toxicity to A. salina was also reduced (LC50 value of 0.28±0.01mgmL(-1)). In conclusion, M. oleifera flower extract had deleterious effects on B. glabrata adults and embryos. However, unrestricted use to control schistosomiasis should be avoided due to the toxicity of this extract on A. salina.

  19. The endocrine disruptor effect of the herbicides atrazine and glyphosate on Biomphalaria alexandrina snails.

    Science.gov (United States)

    Omran, Nahla Elsayed; Salama, Wesam Mohamed

    2016-04-01

    Atrazine (AZ) and glyphosate (GL) are herbicides that are widely applied to cereal crops in Egypt. The present study was designed to investigate the response of the snailBiomphalaria alexandrina(Mollusca: Gastropoda) as a bioindicator for endocrine disrupters in terms of steroid levels (testosterone (T) and 17β-estradiol (E)), alteration of microsomal CYP4501B1-like immunoreactivity, total protein (TP) level, and gonadal structure after exposure to sublethal concentrations of AZ or GL for 3 weeks. In order to study the ability of the snails' recuperation, the exposed snails were subjected to a recovery period for 2 weeks. The results showed that the level of T, E, and TP contents were significantly decreased (p ≤ 0.05) in both AZ- and GL-exposed groups compared with control (unexposed) group. The level of microsomal CYP4501B1-like immunoreactivity increased significantly (p ≤ 0.05) in GL- and AZ-exposed snails and reach nearly a 50% increase in AZ-exposed group. Histological investigation of the ovotestis showed that AZ and GL caused degenerative changes including azoospermia and oocytes deformation. Interestingly, all the recovered groups did not return back to their normal state. It can be concluded that both herbicides are endocrine disrupters and cause cellular toxicity indicated by the decrease of protein content and the increase in CYP4501B1-like immunoreactivity. This toxicity is irreversible and the snail is not able to recover its normal state. The fluctuation of CYP4501B1 suggests that this vertebrate-like enzyme may be functional also in the snail and may be used as a biomarker for insecticide toxicity.

  20. 3D-ultrastructure, functions and stress responses of gastropod (Biomphalaria glabrata rhogocytes.

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    Maria Kokkinopoulou

    Full Text Available Rhogocytes are pore cells scattered among the connective tissue of different body parts of gastropods and other molluscs, with great variation in their number, shape and size. They are enveloped by a lamina of extracellular matrix. Their most characteristic feature is the "slit apparatus", local invaginations of the plasma membrane bridged by cytoplasmic bars, forming slits of ca. 20 nm width. A slit diaphragm creates a molecular sieve with permeation holes of 20×20 nm. In blue-blooded gastropods, rhogocytes synthesize and secrete the respiratory protein hemocyanin, and it has been proposed-though not proven-that in the rare red-blooded snail species they might synthesize and secrete the hemoglobin. However, the cellular secretion pathway for respiratory proteins, and the functional role(s of the enigmatic rhogocyte slit apparatus are still unclear. Additional functions for rhogocytes have been proposed, notably a role in protein uptake and degradation, and in heavy metal detoxification. Here we provide new structural and functional information on the rhogocytes of the red-blooded freshwater snail Biomphalaria glabrata. By in situ hybridization of mantle tissues, we prove that rhogocytes indeed synthesize hemoglobin. By electron tomography, the first three dimensional (3D reconstructions of the slit apparatus are provided, showing detail of highly dense material in the cytoplasmic bars close to the slits. By immunogold labelling, we collected evidence that a major component of this material is actin. By genome databank mining, the complete sequence of a B. glabrata nephrin was obtained, and localized to the rhogocytes by immunofluorescence microscopy. The presence of both proteins fit the ultrastructure-based hypothesis that rhogocytes are related to mammalian podocytes and insect nephrocytes. Reactions of the rhogocytes to deprivation of food and cadmium toxification are also documented, and a possible secretion pathway of newly synthesized

  1. Usnic acid potassium salt: an alternative for the control of Biomphalaria glabrata (Say, 1818.

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    Mônica C B Martins

    Full Text Available In Brazil, the snail Biomphalaria glabrata is the most important vector of schistosomiasis due to its wide geographical distribution, high infection rate and efficient disease transmission. Among the methods of schistosomiasis control, the World Health Organization recommends the use of synthetic molluscicides, such as niclosamide. However, different substances of natural origin have been tested as alternatives for the control or eradication of mollusks. The literature describes the antitumor, antimicrobial and antiviral properties of usnic acid as well as other important activities of common interest between medicine and the environment. However, usnic acid has a low degree of water solubility, which can be a limiting factor for its use, especially in aquatic environments, since the organic solvents commonly used to solubilize this substance can have toxic effects on aquatic biota. Thus, the aim of the present study was to test the potassium salt of usnic acid (potassium usnate with regard to molluscicidal activity and toxicity to brine shrimp (Artemia salina. To obtain potassium usnate, usnic acid was extracted with diethyl ether isolated and purified from the lichen Cladonia substellata. Biological assays were performed with embryos and adult snails of B. glabrata exposed for 24 h to the usnate solution solubilized in dechlorinated water at 2.5; 5 and 10 µg/ml for embryos, 0.5; 0.9; 1;5 and 10 µg/ml for mollusks and 0.5; 1; 5; 10 µg/ml for A. salina. The lowest lethal concentration for the embryos and adult snails was 10 and 1 µg/ml, respectively. No toxicity to A. salina was found. The results show that modified usnic acid has increased solubility (100% without losing its biological activity and may be a viable alternative for the control of B. glabrata.

  2. Usnic acid potassium salt: an alternative for the control of Biomphalaria glabrata (Say, 1818).

    Science.gov (United States)

    Martins, Mônica C B; Silva, Monique C; Silva, Luanna R S; Lima, Vera L M; Pereira, Eugênia C; Falcão, Emerson P S; Melo, Ana M M A; da Silva, Nicácio Henrique

    2014-01-01

    In Brazil, the snail Biomphalaria glabrata is the most important vector of schistosomiasis due to its wide geographical distribution, high infection rate and efficient disease transmission. Among the methods of schistosomiasis control, the World Health Organization recommends the use of synthetic molluscicides, such as niclosamide. However, different substances of natural origin have been tested as alternatives for the control or eradication of mollusks. The literature describes the antitumor, antimicrobial and antiviral properties of usnic acid as well as other important activities of common interest between medicine and the environment. However, usnic acid has a low degree of water solubility, which can be a limiting factor for its use, especially in aquatic environments, since the organic solvents commonly used to solubilize this substance can have toxic effects on aquatic biota. Thus, the aim of the present study was to test the potassium salt of usnic acid (potassium usnate) with regard to molluscicidal activity and toxicity to brine shrimp (Artemia salina). To obtain potassium usnate, usnic acid was extracted with diethyl ether isolated and purified from the lichen Cladonia substellata. Biological assays were performed with embryos and adult snails of B. glabrata exposed for 24 h to the usnate solution solubilized in dechlorinated water at 2.5; 5 and 10 µg/ml for embryos, 0.5; 0.9; 1;5 and 10 µg/ml for mollusks and 0.5; 1; 5; 10 µg/ml for A. salina. The lowest lethal concentration for the embryos and adult snails was 10 and 1 µg/ml, respectively. No toxicity to A. salina was found. The results show that modified usnic acid has increased solubility (100%) without losing its biological activity and may be a viable alternative for the control of B. glabrata.

  3. Effects of endosulfan and ethanol on the reproduction of the snail Biomphalaria tenagophila: a multigeneration study.

    Science.gov (United States)

    Oliveira-Filho, Eduardo Cyrino; Grisolia, Cesar Koppe; Paumgartten, Francisco Jose Roma

    2009-04-01

    Endosulfan (END) is an insecticide used in agriculture and as a wood preservative. Since END is practically insoluble in water, ethanol (ETOH) is often employed as a carrier solvent to spike it in the test medium in aquatic toxicity assays. In this study were investigated the effects of END and ETOH on the reproduction of the freshwater snail Biomphalaria tenagophila exposed over three successive generations. END (0, 0.001, 0.01, 0.1 mg L(-1)) was dissolved in the medium water using ETOH (up to 19.8 mg L(-1)) as carrier solvent. ETOH (19.8, 198, 1980 mg L(-1)) alone was tested as well. Adult snails (F(0)-generation) were exposed to END and ETOH for 8 weeks. The F(1)-generation continued to be exposed from embryo to reproductive maturity, while their descendants (F(2)) were exposed until day 10 after spawning. Effects on the fecundity (8-week production of eggs and egg-masses) of mature F(0) and F(1) snails were evaluated. Developmental toxicity was investigated in F(1) and F(2) embryos. END at the highest level tested (0.1 mg L(-1)) inhibited egg production by F(0) and F(1) snails. ETOH at levels 198 mg L(-1) also reduced fecundity of F(0) and F(1) an effect that was apparently aggravated by exposure over successive generations. END 0.1 mg L(-1) increased mortality and malformations and decreased hatching among F(1) embryos. ETOH drastically reduced the proportion of hatchings among F(2) embryos. The study-derived NOECs (no-observed-effect-concentrations) for END was 0.01 mg L(-1) (reduction in fecundity), and for ETOH were 19.8 mg L(-1) for reduction in fecundity and toxicity (hatching retardation).

  4. Radioprotective effect of the extract of Ziziphus joazeiro and Anacardium occidentale on embryos of Biomphalaria glabrata submitted to ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, Williams N.; Silva, Luanna R.S.; Silva, Edvane B. [Universidade Federal de Pernambuco (DEN/UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia; Silva, Ronaldo C. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Genetica; Lacerda, Laila B.N.; Silva, Hianna A.M.F.; Santos, Mariana L.O.; Sa, Jose L.F.; Melo, Ana M.M.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de de Biofisica e Radiobiologia. Lab. de Radiobiologia

    2011-07-01

    Electromagnetic radiations are energies that can be classified as non-ionizing and ionizing. This type of energy is propagated by a material medium and the vacuum. The important characteristic of ionizing radiation is the localized release of large amounts of energy. The biological effects of radiation result principally from damage to DNA, which is the critical target. Given these harmful effects caused by radiation highlights the importance of acquiring knowledge about the radioprotective substance, because they act to protect the living tissue, decreasing the damage he caused by the effects of radiation. In this study we investigated the radioprotective effect of extract hydroalcoholic of Ziziphus joazeiro and Anacardium occidentale on embryos of Biomphalaria glabrata. The embryos of Biomphalaria glabrata pigmented were divided into 18 groups of 100 specimens. The experimental groups were exposed to the extracts at a concentration of 200 ppm and then irradiated. For irradiation, we used a source of {sup 60}Co (Gammacell of Radionics Labs. Dose rate = 4.359 Gy/h). The viability of the embryos was examined using a stereoscopic microscope and statistical analysis was performed using the test Student-Newman-Keuls and {chi}{sup 2}. Our results showed that the extracts of hydroalcoholic Ziziphus joazeiro showed radioprotective effect and that the aqueous extract of the bark of Anacardium occidentale exhibited a reduction in its embryotoxic effect. (author)

  5. Schistosoma mansoni: continuous variation in susceptibility of the vector snail of schistosomiasis, Biomphalaria tenagophila I. Self-fertilization-lineage.

    Science.gov (United States)

    Mascara, D; Kawano, T; Magnanelli, A C; Silva, R P; Sant' Anna, O A; Morgante, J S

    1999-11-01

    Mascara, D., Kawano, T., Magnanelli, A. C., Silva, R. P. S., Sant' Anna, O. A., and Morgante, J. S. 1999. Schistosoma mansoni: continuous variation in susceptibility of the vector snail of schistosomiasis, Biomphalaria tenagophila I. Self-Fertilization-Lineage. Experimental Parasitology 93, 133-141. Artificial selection of Biomphalaria tenagophila snails for susceptibility to infection by Schistosoma mansoni (Brazilian SJ strain) was carried out from natural populations. After five self-fertilization generations, two lineages were isolated and were designated as SUSC (highly susceptible 93-100%) and RES (nonsusceptible 5-0%). Length of the prepatent period, cercarial production, and mortality of the hosts in postexposure were determined in all generations (F(1)-F(8)) and were analyzed as quantitative traits related to host susceptibility. Distribution patterns of frequencies were observed within snail families (samples derived from one F(0) snail), these traits showing a significant influence by selection applied to susceptibility. The multiple quantitative classes were described in terms of continuous variation. During the selection of SUSC lineage, classes with higher values of prepatent length and lower cercarial production were eliminated, and the heritability calculated for these two traits was 0.811 and 0.709, respectively. Experimental results were correlated with an increase in the level of susceptibility in the generations selected and are discussed in relation to inheritance patterns as well as the quantitative variation of susceptibility.

  6. Biomphalaria obstructa (Morelet, 1849: a study of topotypic specimens (Mollusca: pulmonata: planorbidae

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    W. Lobato Paraense

    1990-12-01

    Full Text Available A description of Biomphalaria obstructa (Morelet, 1849, based on specimens collected at its type locality - isla del carmen, state of Campeche, Mexico - is presented. The Shell is small, 13 mm in diameter, 3.5 mm in width and with 5.75 whorls in the largest specimen, thin, moderately lustrous and translucent, horn-colored. Whorls increasing regularly (neither slowly nor rapidly in diameter, rounded on the periphery side, bluntly angular on the left. Suture well-marked, deeper on the left. Right side widely concave, with first whorl deeply situated and partly hidden by the next. Left side shallower than right one, largely flattened, with first whorl plaintly visible. Aperture roundly heart-shaped, usually in the same plane as the body whorl but somewhat deflected to the left (less frequently to the right in some specimens. Peristome sharp, seldom blunt; a distinct callus on the parietal wall. A number of young shells develop one set (seldom more of apertural lamellae which tend to be resorbed as the shell grows. Absence of renal ridge. Ovotestis with about 70 mostly unbrached diverticula. Seminal vesicle beset with well-developed knoblike to fingerlike diverticula. Vaginal pouch more or less developed. Spermatheca club-shaped when empty, egg-shaped when full, and with intermediate forms between those extremes. Spermathecal body usually somewhat longer than the duct. Prostate with 7 to 20 (mean 12.06 ± 2.51 usually short diverticula which give off plumpish branches spreading out in a fan shape and overlapping to some extent their immediate neighbors. Foremost prostatic diverticulum nearly always partially or completely inserted between the spermathecal body and the uterine wall. Penial sheath consistently narrower and shorter than the prepuce. Muscular coat of the penis consisting of an inner longitudinal and an outer circular layers. Ratios between organ lengths: caudal to cephalic parts of female duct = 0.55 to 1.37 (mean 0.85 +- 0.17; cephalic

  7. Changes in energetic metabolism of Biomphalaria glabrata (Mollusca, Planorbidae in response to exogenous calcium

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    L. D. Silva

    Full Text Available Abstract Calcium is considered an essential element for the metabolism of aquatic snail Biomphalaria glabrata (Say, 1818, intermediate host of Schistosoma mansoni Sambon, 1907 in Brazil, and represents a limiting factor to its distribution and adaptation to the environment. This study investigated the effect of different concentrations of exogenous CaCO3 on the energetic metabolism of B. glabrata for better understanding the physiological interference of chemical elements dissolved in the environment with the physiology of this species. Sixty-day-old snails were distributed into six groups, five exposed to different concentrations of CaCO3 (20, 40, 60, 80 and 100 mg/L and a control group. The exposure to CaCO3 was assessed over time, with analysis of 15 snails of each group in the following intervals: 1, 14, 21 or 30 days for hemolymph extraction. Concentrations of calcium and glucose in the hemolymph were determined by commercial kits, and organic acids were extracted using an ion exchange column and analyzed by high-performance liquid chromatography. Concentration of calcium in the hemolymph showed no significant difference (p>0.05 from the control group and between the concentrations tested. Concentration of glucose decreased (p<0.05 in the treatments of exposure to 20 and 40 mg/L and increased when exposed to 80 and 100 mg/L CaCO3 compared to control and to other concentrations tested over 30 days. The organic acids pyruvate, oxaloacetate, citrate, succinate, fumarate, beta-hydroxybutyrate and lactate presented increased concentrations, while propionate and acetoacetate, decreased concentrations, when exposed to CaCO3 compared to control. Considering the influence of different periods of exposure to CaCO3, on the 14th day, there were stronger alterations in the metabolism of B. glabrata. In conclusion, exposure to CaCO3 reduced the concentration of glucose, which is metabolized into pyruvate, the final product of glycolysis, and also

  8. Aspectos imunológicos e parasitológicos em Biomphalaria tenagophila infectadas por Schistosoma mansoni e outros Digenea Immunological and parasitological aspects of Biomphalaria tenagophila infected by Schistosoma mansoni and other Digenea

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    Doralice de Souza Luro Balan

    1993-12-01

    Full Text Available Estudou-se o comportamento de amebócitos de Biomphalaria tenagophila infectadas por Schistosoma mansoni, por outros Digenea e a resistência à superinfecção, presente em infecções mistas. Foi verificada a atividade fagocitária dos amebócitos, o número destas células circulantes, a reação amebocitária nos tecidos, o perfil eletroforético da hemolinfa, além da reação de imunodifusão. Concluiu-se que moluscos infectados por outros Digenea apresentam resistência à superinfecção por S. mansoni, sendo que os amebócitos parecem não ter participação direta na destruição dos esporocistos de S. mansoni nesta eventualidade. Nos moluscos infectados observou-se maior número de amebócitos circulantes e aumento de capacidade fagocitária destas células.The behavior of Biomphalaria tenagophila amoebocytes was studied in infections produced by Schistosoma mansoni and other Digenea, The resistance to superinfection was also verified in mixed infections. Data on amoebocyte phagocytic activity, on the number of amoebocytes in hemolymph, and on amoebocyte tissue ractions were obtained and eletrophoretic and imunodiffusion examinations of the hemolymph were carried out. It was concluded that the snails infected with Digenea show resistance to superinfection with S. mansoni. Apparently sporocysts are not destroyed by the action of amoebocytes. An increase in amoebocyte phagocytic activity was discovered in infected snails. Immunoeletrophoresis shows quantitative and qualitative differences in the hemolymph of the infected snails.

  9. Molluscicidal activity of Physalis angulata L. extracts and fractions on Biomphalaria tenagophila (d'Orbigny, 1835 under laboratory conditions

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    Santos José Augusto A dos

    2003-01-01

    Full Text Available The main objective of this research is to evaluate the molluscicide activity of Physalis angulata L. Biomphalaria tenagophila specimens under laboratory conditions. Extracts and fractions were supplied by the Laboratório de Química de Produtos Naturais, Farmanguinhos-Fiocruz. Experiments were performed according to the methodology described by the World Health Organization for molluscicide tests using the concentrations from 0.1 to 500 mg/l of the extracts, fractions and of a pool of physalins modified steroids present in this species. The results show that ethyl acetate and acetone extracts from the whole plant, the ethanolic extracts of the roots and the physalins pool from stems and leaves were active. Only the whole plant extracts were available in sufficient quantity for the determination of LD50 and LD90 values.

  10. Dominant character of the molecular marker of a Biomphalaria tenagophila strain (Mollusca: Planorbidae resistant to Schistosoma mansoni

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    Rosa Florence Mara

    2004-01-01

    Full Text Available Biomphalaria tenagophila population from Taim (state of Rio Grande do Sul, Brazil is totally resistant toSchistosoma mansoni, and presents a molecular marker of 350 bp by polymerase chain reaction and restriction fragment length polymorphism of the entire rDNA internal transcriber spacer. The scope of this work was to determine the heritage pattern of this marker. A series of cross-breedings between B. tenagophila from Taim (resistant and B. tenagophila from Joinville, state of Santa Catarina (susceptible was carried out, and their descendants F1 and F2 were submitted to this technique. It was possible to demonstrate that the specific fragment from Taim is endowed with dominant character, since the obtained segregation was typically mendelian.

  11. Molluscicidal activity of Moringa oleiferaon Biomphalaria glabrata: integrated dynamics to the control of the snail host of Schistosoma mansoni

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    Cesar Luiz Pinto Ayres Coelho da Silva

    2013-10-01

    Full Text Available The ground seed of Moringa oleifera Lam., Moringaceae, has been evaluated for its molluscicidal activity against the snails Biomphalaria glabrata, Physa marmorata and Melanoides tuberculatus. The results show that M. oleifera is active against B. glabrata (LC50 0.419 g/l; LC90 1.021 g/l and P. marmorata (LC50 0.339 g/l; LC90 0.789 g/l but has no effect against M. tuberculatus. The great innovation of the use of M. oleifera, in addition to being innocuous to humans, is the present nutritional potential for humans and animals as well as providing an ecosystemic service as water purifier.

  12. The lethality of Euphorbia conspicua to adults of Biomphalaria glabrata, cercaria of Schistosoma mansoni and larvae of Artemia salina.

    Science.gov (United States)

    dos Santos, Aldenir F; de Azevedo, Denise P L; dos Santos Mata, Rosalina da C; de Mendonça, Dina I M Dinis; Sant'Ana, Antônio E Goulart

    2007-01-01

    Leaf extracts of Euphorbia conspicua (Euphorbiaceae), together with the latex and fractions derived therefrom, were evaluated for their molluscicidal and cercaricidal activities and their toxicities to brine shrimps. Whilst the leaf extracts were inactive against Biomphalaria glabrata, the latex, its triterpenic fraction and irritant fractions I and II exhibited high activities against adult snails with LC90 values of 4.87, 10.55, 0.64 and 0.10 microg/mL, respectively. The latex and its derived fractions were considered lethal to the cercaria of Schistosoma mansoni at concentrations of 100 microg/mL. The toxicities of the latex and the irritant fractions, but not of the triterpenic fraction, against Artemia salina were high with LC50 values < 10 microg/mL. The possible application of the latex of E. conspicua as an alternative natural molluscicide is considered.

  13. Lamella formation and emigration from the water by a laboratory colony of Biomphalaria glabrata (SAY in flow-through system

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    Ricardo D. A. Dannemann

    1992-01-01

    Full Text Available Lamella formation and emigration from the water were investigated in juvenile Biomphalaria glabrata reared at two temperatures in aquaria with a constant water flow. Most snails (97.4% reared at the lower temperature (21- C formed lamella at the shell aperture and emigrated from the water, whereas only 10.1% did so at 25- C. Eighty percent of emigrations at 21- C occurred within a period of 15 days, 70-85 days after hatching. A comparison of the studies done so far indicates that the phenomenon may be affected by the ageing of snail colonies kept in the laboratory and their geographic origin, rather than the rearing conditions. This hypothesis, however, requires experimental confirmation.

  14. Simultaneous infection of Schistosoma mansoni and S. rodhaini in Biomphalaria glabrata: impact on chronobiology and cercarial behaviour

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    Richards Louisa

    2008-12-01

    Full Text Available Abstract Background The chances of a schistosome cercaria encountering a suitable definitive host may be enhanced by emergence from the molluscan intermediate host with maximal glycogen stores and by an appropriate chronobiological rhythm. This study aimed to identify and characterize the effects of potential competitive interactions in the snail host Biomphalaria glabrata, between the closely-related Schistosoma mansoni and S. rodhaini, on phenotypic behavioural traits. It was predicted that inter-specific competition would affect chronobiological emergence rhythms and reduce the activity of schistosome swimming behavioural traits. Biomphalaria glabrata snails (120 were exposed to either S. mansoni or S. rodhaini single infections, or a mixed infection of both species simultaneously and the resulting cercarial phenotypic traits were characterised. Cercariae were identified from co-exposed snails by amplification and sequencing of the mitochondrial cytochrome oxidase subunit 1 (CO1. Results S. mansoni and S. rodhaini largely maintained their distinct chronobiological rhythms after mixed exposures and infections. However, inter-specific competition appeared to result in a restriction of the shedding pattern of S. rodhaini and slight shift in the shedding pattern of S. mansoni. Inter-specific competition also significantly lowered hourly cercarial production for both parasite species in comparison to single exposures and infections and reduced cercarial swimming activity. Conclusion Inter-specific competition was shown to influence cercarial production, chronobiology and activity and should therefore be investigated further in field situations to determine the effects of these changes on parasite fitness (incorporating both host finding and infectivity where these two species overlap. Importantly this competition did not result in a large change in chronobiological emergence of cercariae for either species indicating that it would not have a large

  15. Analysis of toxicity of Anacardium occidentale L. extract submitted to ionizing radiation on embryos of Biomphalaria glabrata and Artemia salina

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Hianna A.M.F.; Sa, Jose L.F.; Lima, Claudia S.A.; Amancio, Francisco F.; Melo, Ana M.M.A., E-mail: hiannaamfs@gmail.com, E-mail: luismuma6@gmail.com, E-mail: claudia.salima@gmail.com, E-mail: amancioff@bol.com.br, E-mail: amdemelo@hotmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Biofisica e Radiobiologia; Ribeiro, Luanna R.S.; Santos, Gustavo H.F.; Silva, Edvane B., E-mail: luannaribeiro_lua@hotmail.com, E-mail: santosghf@hotmail.com, E-mail: edvborges@yahoo.com.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia

    2013-07-01

    The use of gamma radiation as a sterilization method for herbs, herbal medicines and foods, shows positive results regarding the retention of such products, economy and safety of the method. However, it is known that this method of processing plant material can cause chemical changes in these products related to the type of material, its components and the dose received. Evaluated, in the present study, the action of gamma radiation as a modifier of toxicity extract of Anacardium occidentale Linn. To evaluate the toxicity of the extract irradiated at doses of 5.0, 7.5 and 10.0 kGy and concentrations of 250, 500 and 1000 mg/L was used bioassays with Artemia salina and Biomphalaria glabrata. For the test to A. salina, 520 specimens were used divided into groups of 10 larvae. For the bioassay with B. glabrata, 3900 specimens were used divided into groups of, approximately, 100 embryos. Larvae of A. salina and embryos were subjected to extracts irradiated and unirradiated for 24 hours. The bioassay with A. salina, showed a decrease, compared to extract unirradiated and irradiated at doses of 5.0 and 7.5 kGy, of extract irradiated with 10 kGy, where the mortality did not differ from the control group. In tests with embryos was observed an increase in the toxicity of the extract at a dose of 7.5 kGy and a decrease in the dose of 10.0 kGy. The radiation promoted changes in the toxicity of leaves extracts of Anacardium occidentale Linn. on embryos of Biomphalaria glabrata and Artemia salina. (author)

  16. Interaction between primary and secondary sporocysts of Schistosoma mansoni and the internal defence system of Biomphalaria resistant and susceptible to the parasite

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    Ana Carolina Alves de Mattos

    2011-06-01

    Full Text Available The outcome of the interaction between Biomphalaria and Schistosoma mansoni depends on the response of the host internal defence system (IDS and the escape mechanisms of the parasite. The aim of this study was to evaluate the responsiveness of the IDS (haemocytes and soluble haemolymph factors of resistant and susceptible Biomphalaria tenagophila lineages and Biomphalaria glabrata lineages in the presence of in vitro-transformed primary sporocysts and secondary sporocysts obtained from infected B. glabrata. To do this, we assayed the cellular adhesion index (CAI, analysed viability/mortality, used fluorescent markers to evaluate the tegumental damage and transplanted secondary sporocysts. B. tenagophila Taim was more effective against primary and secondary sporocystes than the susceptible lineage and B. glabrata. Compared with secondary sporocysts exposed to B. tenagophila, primary sporocysts showed a higher CAI, a greater percentage of dead sporocysts and were labelled by lectin from Glycine max and Alexa-Fluor 488 fluorescent probes at a higher rate than the secondary sporocysts. However, the two B. tenagophila lineages showed no cercarial shedding after inoculation with secondary sporocysts. Our hypothesis that secondary sporocysts can escape the B. tenagophila IDS cannot be confirmed by the transplantation experiments. These data suggest that there are additional mechanisms involved in the lower susceptibilty of B. tenagophila to S. mansoni infection.

  17. Padronização da técnica de marcação de caramujos Biomphalaria glabrata com radioestroncio Standardization of the technic of labeling Biomphalaria glabrata snails with radiostrontium

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    Miguel Archanjo Muniz Leal

    1982-06-01

    Full Text Available Caramujos Biomphalaria glabrata vetor da esquistossomose mansônica, utilizados em experiências de campo, nas quais se faz necessário sua identificação e/ou localização, devem ser marcados com radioestrôncio 85,89 ou 90. Sua marcação em laboratório deve ser procedida em aquários de vidro sem fundo de areia, temperatura de 26,5 ± 1ºC, pH ajustado ao valor encontrado no "habitat", aeração artificial, alimentação diária com pequenas porções de alface fresca e 25 ml de água desionizada por caramujo. O nível de atividade no caramujo pode ser estimado sabendo-se que para o tempo de marcação de 5 dias e atividades iniciais de 0,036 a 0,362 µCi/ml, a captação global para grupos de 10 caramujos está em torno de 84 ± 2% e que a marcação em água contendo cálcio, praticamente não se altera até concentrações de 50ppm. A sobrevida ao longo de nove semanas não foi influenciada pela presença de radioestrôncio no caramujo.The vector snail of schistosomiasis mansoni, Biomphalaria glabrata, when used in field experiments in which it is to be recovered and/or located, should be labeled with radiostrontium 85,89 or 90. The labeling in laboratory should be carried out in an artificially aerated aquarium with 25 ml of deionized water per snail, without sand at the bottom, at a temperature of 26.5 ± 1ºC, pH adjusted to the value found in the natural habitat, and the snails should be fed with small pieces of fresh lettuce. The level of snail activity can be estimated taking into account that, for a labeling time of 5 days and initial activities of 0.036 to 0.362 µCi/ml, the global uptake for groups of 10 snails is about 84 ± 2% and that labeling in calcium-containing water parctically does not change till a 50 ppm concentration. Survival along 9 weeks was not influenced by the presence of radiostrontium in the snail.

  18. Contribuição ao estudo da biologia de Biomphalaria occidentalis Paraense, 1981 e de Biomphalaria tenagophila (d'Orbigny, 1835, em condições de laboratório

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    Maísa Rose Domenico Elmor

    1992-10-01

    Full Text Available Com o objetivo de comparar a duração do período embrionário, a fecundidade e a fertilidade de Biomphalaria occidentalis Paraense, 1981 com a de B, tenagophila (d'Orbigny, 1835, exemplares de ambas as espécies foram criados em aquários dotados das mesmas características. Os ovos depostos pelos caramujos foram contados sob lupa binocular e seu desenvolvimento embrionário foi observado até a eclosão. Assim foi obtido o número total de posturas e de ovos por caramujo, bem como o número total de ovos eclodidos por postura para cada período de trinta dias, ou seja, a taxa de eclosão por período. O experimento teve a duração de doze meses e os resultados obtidos são válidos para condições de laboratório.

  19. Aspectos imunológicos e parasitológicos em Biomphalaria tenagophila infectadas por Schistosoma mansoni e outros Digenea

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    Doralice de Souza Luro Balan

    1993-12-01

    Full Text Available Estudou-se o comportamento de amebócitos de Biomphalaria tenagophila infectadas por Schistosoma mansoni, por outros Digenea e a resistência à superinfecção, presente em infecções mistas. Foi verificada a atividade fagocitária dos amebócitos, o número destas células circulantes, a reação amebocitária nos tecidos, o perfil eletroforético da hemolinfa, além da reação de imunodifusão. Concluiu-se que moluscos infectados por outros Digenea apresentam resistência à superinfecção por S. mansoni, sendo que os amebócitos parecem não ter participação direta na destruição dos esporocistos de S. mansoni nesta eventualidade. Nos moluscos infectados observou-se maior número de amebócitos circulantes e aumento de capacidade fagocitária destas células.

  20. Propiedad molusquicida de Euphorbia laurifolia A. Juss (Euphorbiaceae contra Biomphalaria glabrata Say hospedador intermediario de Schistosoma mansoni

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    José Ángel Mogollón-Morales

    2016-08-01

    Full Text Available En América Latina, los caracoles de Biomphalaria glabrata (Planorbidae son hospedadores intermediarios del parasito Schistosoma mansoni, agentes causantes de la schistosomiasis, una parasitosis que afecta a millones de personas en el mundo. El presente trabajo evalúa el papel de la especie Euphorbia laurifolia A. Juss (Euphorbiaceae contra B. glabrata. La actividad molusquicida se evaluó de acuerdo a los parámetros sugeridos por la Organización Mundial de la Salud. Se utilizaron caracoles de B. glabrata criados en el laboratorio. Se realizaron diferentes bioensayos utilizando extractos metanólico crudo, en n-hexano, en acetato de etilo y en metanol de las partes aéreas de E. laurifolia a diferentes concentraciones. Los resultados demostraron que esta especie posee una potente actividad letal con todos los extractos estudiados contra caracoles de B. glabrata, considerándose el mejor el extracto de acetato de etilo, el cual presentó una DL50 de 5,57 ppm.

  1. A multistrain approach to studying the mechanisms underlying compatibility in the interaction between Biomphalaria glabrata and Schistosoma mansoni.

    Science.gov (United States)

    Galinier, Richard; Roger, Emmanuel; Moné, Yves; Duval, David; Portet, Anaïs; Pinaud, Silvain; Chaparro, Cristian; Grunau, Christoph; Genthon, Clémence; Dubois, Emeric; Rognon, Anne; Arancibia, Nathalie; Dejean, Bernard; Théron, André; Gourbal, Benjamin; Mitta, Guillaume

    2017-03-01

    In recent decades, numerous studies have sought to better understand the mechanisms underlying the compatibility between Biomphalaria glabrata and Schistosoma mansoni. The developments of comparative transcriptomics, comparative genomics, interactomics and more targeted approaches have enabled researchers to identify a series of candidate genes. However, no molecular comparative work has yet been performed on multiple populations displaying different levels of compatibility. Here, we seek to fill this gap in the literature. We focused on B. glabrata FREPs and S. mansoni SmPoMucs, which were previously demonstrated to be involved in snail/schistosome compatibility. We studied the expression and polymorphisms of these factors in combinations of snail and schistosome isolates that display different levels of compatibility. We found that the polymorphism and expression levels of FREPs and SmPoMucs could be linked to the compatibility level of S. mansoni. These data and our complementary results obtained by RNA-seq of samples from various snail strains indicate that the mechanism of compatibility is much more complex than previously thought, and that it is likely to be highly variable within and between populations. This complexity must be taken into account if we hope to identify the molecular pathways that are most likely to be good targets for strategies aimed at blocking transmission of the parasite through the snail intermediate host.

  2. Bioactivity Evaluation of Plant Extracts Used in Indigenous Medicine against the Snail, Biomphalaria glabrata, and the Larvae of Aedes aegypti

    Science.gov (United States)

    dos Santos, Edilson Alves; de Carvalho, Cenira M.; Costa, Ana L. S.; Conceição, Adilva S.; Moura, Flávia de B. Prado; Santana, Antônio Euzébio Goulart

    2012-01-01

    This investigation examined the molluscicidal and larvicidal activity of eight plants that are used in the traditional medicine of the Pankararé indigenous people in the Raso da Catarina region, Bahia state, Brazil. The tested plants were chosen based on the results of previous studies. Only those plants that were used either as insect repellents or to treat intestinal parasitic infections were included in the study. Crude extracts (CEs) of these plants were tested for their larvicidal activity (against Aedes aegypti larvae in the fourth instar) and molluscicidal activity (against the snail Biomphalaria glabrata). The plant species Scoparia dulcis and Helicteres velutina exhibited the best larvicidal activities (LC50 83.426 mg/L and LC50 138.896 mg/L, resp.), and Poincianella pyramidalis, Chenopodium ambrosoides, and Mimosa tenuiflora presented the best molluscicidal activities (LC50 0.94 mg/L, LC50 13.51 mg/L, and LC50 20.22 mg/L, resp.). As we used crude extracts as the tested materials, further study is warranted to isolate and purify the most active compounds. PMID:22194773

  3. Comparative Study of the Molluscicidal Activity of Some Plant Extracts on the Snail Vector of Schistosoma mansoni, Biomphalaria alexandrina

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    M. Al-Hazmi

    2011-01-01

    Full Text Available Schistosomiasis is considered as one of the most important trematode disease of man. The most important goal of the present study is to use the natural plants as cheaper and available sources for snail control. The present investigation concerned with the evaluation of toxicological, biological and physiological effects of water suspension, cold water and boiled water extracts of Agave filifera whole plant, Ammi majus flowers and leaves and Canna indica flowers and leaves comparing with the effect of different sulphate compounds. The present work revealed that, copper sulphate as well as the water suspension of Ammi majus flowers and leaves disclosed the most potent effect on the cumulative mortality after 6 weeks exposure periods. Also, egg laying capacity and egg hatchability of Biomphalaria alexandrina snails were affected with the exposure to CuSO4 and water suspension of Ammi majus flowers. The sublethal doses (LC10 of copper sulphate and water suspension of the tested plants reduced the total protein and total lipid contents of the hemolymph of B. alexandrina snails. The activity of transaminases enzymes as well as acetylcholinesterase had been affected by the exposure to the sublethal doses of copper sulphate and the water suspension of the tested plants. Also, histopathological changes were recorded in hermaphrodite gland of B. alexandrina snails post 6 weeks of exposure.

  4. Biomphalaria tenagophila potencial vector of Schistosoma mansoni in the Paraná River basin (Argentina and Paraguay).

    Science.gov (United States)

    Borda, C Edgardo; Rea, María Josefa F

    2007-05-01

    Susceptibility and compatibility experiments were carried out with 700 Biomphalaria tenagophila from the Paraná River basin exposed to infection with Schistosoma mansoni. Individual infection was performed with 10 miracidia of SJ2 strain from the Paraiba valley (Brazil) originally infective to B. tenagophila. These snails were laboratory-breed progeny of B. tenagophila collected from six localities of Argentina and one from Paraguay. From Argentina: Rincón de Vences (7%) and Posadas (11%) became infected with S. mansoni and the calculation of Frandsen's index (TCP/100) shows that they were Class II poorly compatible. Those snails from Goya (22%), Maloyas (5%), and Berón de Astrada (3%) were Class III compatible to the S. mansoni. None of the 100 snails exposed from Caá-Catí became infected (Class 0 incompatible). Tested samples from Paraguay (Encarnación) were infected (20%) and compatible (Class III). It was also studied the persistence of the infection in 244 snails of the first generation (F1) of those that were susceptible from three places. It was demonstrated an increment of the susceptibility in the F1 from Maloyas (chi2 = 27.22; p = 0.0001) and Posadas (chi2 = 4.24; p = 0.04). The results point out the possibility that schistosomiasis might be able to spread into the Paraná River basin where B. tenagophila exists.

  5. Aspectos imunológicos e parasitológicos em Biomphalaria tenagophila infectadas por Schistosoma mansoni e outros Digenea

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    Balan Doralice de Souza Luro

    1993-01-01

    Full Text Available Estudou-se o comportamento de amebócitos de Biomphalaria tenagophila infectadas por Schistosoma mansoni, por outros Digenea e a resistência à superinfecção, presente em infecções mistas. Foi verificada a atividade fagocitária dos amebócitos, o número destas células circulantes, a reação amebocitária nos tecidos, o perfil eletroforético da hemolinfa, além da reação de imunodifusão. Concluiu-se que moluscos infectados por outros Digenea apresentam resistência à superinfecção por S. mansoni, sendo que os amebócitos parecem não ter participação direta na destruição dos esporocistos de S. mansoni nesta eventualidade. Nos moluscos infectados observou-se maior número de amebócitos circulantes e aumento de capacidade fagocitária destas células.

  6. Biomphalysin, a new β pore-forming toxin involved in Biomphalaria glabrata immune defense against Schistosoma mansoni.

    Science.gov (United States)

    Galinier, Richard; Portela, Julien; Moné, Yves; Allienne, Jean François; Henri, Hélène; Delbecq, Stéphane; Mitta, Guillaume; Gourbal, Benjamin; Duval, David

    2013-03-01

    Aerolysins are virulence factors belonging to the β pore-forming toxin (β-PFT) superfamily that are abundantly distributed in bacteria. More rarely, β-PFTs have been described in eukaryotic organisms. Recently, we identified a putative cytolytic protein in the snail, Biomphalaria glabrata, whose primary structural features suggest that it could belong to this β-PFT superfamily. In the present paper, we report the molecular cloning and functional characterization of this protein, which we call Biomphalysin, and demonstrate that it is indeed a new eukaryotic β-PFT. We show that, despite weak sequence similarities with aerolysins, Biomphalysin shares a common architecture with proteins belonging to this superfamily. A phylogenetic approach revealed that the gene encoding Biomphalysin could have resulted from horizontal transfer. Its expression is restricted to immune-competent cells and is not induced by parasite challenge. Recombinant Biomphalysin showed hemolytic activity that was greatly enhanced by the plasma compartment of B. glabrata. We further demonstrated that Biomphalysin with plasma is highly toxic toward Schistosoma mansoni sporocysts. Using in vitro binding assays in conjunction with Western blot and immunocytochemistry analyses, we also showed that Biomphalysin binds to parasite membranes. Finally, we showed that, in contrast to what has been reported for most other members of the family, lytic activity of Biomphalysin is not dependent on proteolytic processing. These results provide the first functional description of a mollusk immune effector protein involved in killing S. mansoni.

  7. Bioactivity Evaluation of Plant Extracts Used in Indigenous Medicine against the Snail, Biomphalaria glabrata, and the Larvae of Aedes aegypti

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    Edilson Alves dos Santos

    2012-01-01

    Full Text Available This investigation examined the molluscicidal and larvicidal activity of eight plants that are used in the traditional medicine of the Pankararé indigenous people in the Raso da Catarina region, Bahia state, Brazil. The tested plants were chosen based on the results of previous studies. Only those plants that were used either as insect repellents or to treat intestinal parasitic infections were included in the study. Crude extracts (CEs of these plants were tested for their larvicidal activity (against Aedes aegypti larvae in the fourth instar and molluscicidal activity (against the snail Biomphalaria glabrata. The plant species Scoparia dulcis and Helicteres velutina exhibited the best larvicidal activities (LC50 83.426 mg/L and LC50 138.896 mg/L, resp., and Poincianella pyramidalis, Chenopodium ambrosoides, and Mimosa tenuiflora presented the best molluscicidal activities (LC50 0.94 mg/L, LC50 13.51 mg/L, and LC50 20.22 mg/L, resp.. As we used crude extracts as the tested materials, further study is warranted to isolate and purify the most active compounds.

  8. Developmental toxicity, acute toxicity and mutagenicity testing in freshwater snails Biomphalaria glabrata (Mollusca: Gastropoda) exposed to chromium and water samples.

    Science.gov (United States)

    Tallarico, Lenita de Freitas; Borrely, Sueli Ivone; Hamada, Natália; Grazeffe, Vanessa Siqueira; Ohlweiler, Fernanda Pires; Okazaki, Kayo; Granatelli, Amanda Tosatte; Pereira, Ivana Wuo; Pereira, Carlos Alberto de Bragança; Nakano, Eliana

    2014-12-01

    A protocol combining acute toxicity, developmental toxicity and mutagenicity analysis in freshwater snail Biomphalaria glabrata for application in ecotoxicological studies is described. For acute toxicity testing, LC50 and EC50 values were determined; dominant lethal mutations induction was the endpoint for mutagenicity analysis. Reference toxicant potassium dichromate (K2Cr2O7) was used to characterize B. glabrata sensitivity for toxicity and cyclophosphamide to mutagenicity testing purposes. Compared to other relevant freshwater species, B. glabrata showed high sensitivity: the lowest EC50 value was obtained with embryos at veliger stage (5.76mg/L). To assess the model applicability for environmental studies, influent and effluent water samples from a wastewater treatment plant were evaluated. Gastropod sensitivity was assessed in comparison to the standardized bioassay with Daphnia similis exposed to the same water samples. Sampling sites identified as toxic to daphnids were also detected by snails, showing a qualitatively similar sensitivity suggesting that B. glabrata is a suitable test species for freshwater monitoring. Holding procedures and protocols implemented for toxicity and developmental bioassays showed to be in compliance with international standards for intra-laboratory precision. Thereby, we are proposing this system for application in ecotoxicological studies.

  9. Experimental and molecular study of cercariae of Clinostomum sp. (Trematoda: Clinostomidae) from Biomphalaria spp. (Mollusca: Planorbidae) in Brazil.

    Science.gov (United States)

    Pinto, H A; Caffara, M; Fioravanti, M L; Melo, A L

    2015-02-01

    Despite the large number of reports of species of Clinostomum from vertebrate hosts in South America, studies evaluating the molluscan transmitters of these parasites are scarce. In the present study, clinostomatoid cercariae shed from 0.02% (4/17,485) specimens of Biomphalaria spp., collected at the Pampulha reservoir, Belo Horizonte, Minas Gerais, Brazil, were used for experimental infection of Poecilia reticulata . Samples of cercariae from molluscs and metacercariae experimentally obtained from fish were subjected to morphological and molecular analyses and compared with species of Clinostomum reported in the Americas. The cercariae and metacercariae, here identified as Clinostomum sp., present general morphology similar to that reported for Clinostomum marginatum , however, from molecular point of view, differ significantly from North American C. marginatum and other species of Clinostomum reported in South America. These results suggest that the diversity of Clinostomum found in Brazil may be underestimated. Additional studies aimed at molecular characterization of South American species of Clinostomum, including the finding of specimens with sequences similar to that reported for C. marginatum in North America are required.

  10. Identification of protein components of egg masses indicates parental investment in immunoprotection of offspring by Biomphalaria glabrata (gastropoda, mollusca).

    Science.gov (United States)

    Hathaway, Jennifer J M; Adema, Coen M; Stout, Barbara A; Mobarak, Charlotte D; Loker, Eric S

    2010-04-01

    The macromolecules contributed by the freshwater gastropod Biomphalaria glabrata, intermediate host of Schistosoma mansoni, to developing offspring inside egg masses are poorly known. SDS-PAGE fractionated egg mass fluids (EMF) of M line and BB02 B. glabrata were analyzed by MALDI-TOF (MS and tandem MS). A MASCOT database was assembled with EST data from B. glabrata and other molluscs to aid in sequence characterization. Of approximately 20 major EMF polypeptides, 16 were identified as defense-related, including protease inhibitors, a hemocyanin-like factor and tyrosinase (each with possible phenoloxidase activity), extracellular Cu-Zn SOD, two categories of C-type lectins, Gram-negative bacteria-binding protein (GNBP), aplysianin/achacin-like protein, as well as versions of lipopolysaccharide binding protein/bacterial permeability-increasing proteins (LBP/BPI) that differed from those previously described from hemocytes. Along with two sequences that were encoded by "unknown" ESTs, EMF also yielded a compound containing a vWF domain that is likely involved in defense and a polypeptide with homology to the Aplysia pheromone temptin. Further study of B. glabrata pheromones is warranted as these could be useful in efforts to control these schistosome-transmitting snails. Several of the EMF polypeptides were contained in the albumen gland, the organ that produces most EMF. Thus, parental investment of B. glabrata in immunoprotection of its offspring is indicated to be considerable.

  11. Resistência de Biomphalaria peregrina de Santa Rita do Sapucaí, Minas Gerais, a infecção com três cepas de Schistosoma mansoni Resistance of Biomphalaria peregrina from Santa Rita do Sapucaí, State of Minas Gerais, Brazil, to infection with strain of Schistosoma mansoni

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    Cecília Pereira de Souza

    1988-12-01

    Full Text Available Descendentes do planorbídeo Biomphalaria peregrina, coletados em Santa Rita do Sapucaí, Minas Gerais, Brasil, foram expostos a miracídios de três cepas de Schistosoma mansoni: "LE" de Belo Horizonte, MG; "SJ" de São José dos Campos, SP e "AL" do Estado de Alagoas. Dentre 300 exemplares expostos, nenhum se infectou com as três cepas do trematódeo. Por outro lado, 300 exemplares de B. glabrata, dos grupos de controle, apresentaram taxas de infecção de 61,1 a 95,3% com as três cepas do trematódeo. As taxas de mortalidade de B. peregrina e de B. glabrata foram de 20,0 e de 28,0%, respectivamente.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 São José dos Campos, State of São 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.

  12. Resistance of Biomphalaria occidentalis from Varzea das Flores dam, Minas Gerais, to Schistosoma mansoni infection detected by low stringency polymerase chain reaction

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    Cecilia Pereira de Souza

    2001-04-01

    Full Text Available Biomphalaria occidentalis Paraense, 1981 from Varzea das Flores dam, MG, Brazil, was exposed to infection with Schistosoma mansoni. Individual infection was performed with 140 B. occidentalis and 100 B. glabrata snails using LE and SJ strains. Two groups of B. occidentalis were killed after seven day-miracidia exposure to detect S. mansoni DNA, through the low stringency polymerase chain reaction (LS-PCR, and were negative. The infection rates were 69.2% (LE strain and 96.7% (SJ strain for B. glabrata and 0% for B. occidentalis. LS-PCR enabled early resistance diagnosis.

  13. Production of Shistosoma mansoni cercariae by Biomphalaria glabrata from a focus in Belo Horizonte, Minas Gerais Produção de cercárias de Schistosoma mansoni por Biomphalaria glabrata de foco em Belo Horizonte, Minas Gerais

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    Cecília Pereira de Souza

    1994-12-01

    Full Text Available The snail density, levels of infection and the monthly production of Schistosoma mansoni cercariae by Biomphalaria glabrata were determined in a focus of Barreiro de Baixo (Belo Horizonte, MG, Brazil. During a period of 38 months (1984 to 1987 5,366 snails were collected of which 324 (6.03% were infected with S. mansoni. The total number of cercariae shed was 5,667,312. Each snail shed an average of 17,422 cercariae during the time that it was under study in the laboratory. The greatest longevity of infected snails was 218 days. Natural cure was observed in 42 (12.9% of the infected specimens about 130 days after collection. The average snail density in the focus during the period of study was 16.3 snails per scoop. The shedding of cercariae by snails collected from the field was compared with laboratory bred specimens infected in mass with the LE strain of S. mansoni from Belo Horizonte. The laboratory infected snails shed an average of 6,061 cercariae each, a value 2.8 times less than the field specimens due to a shorter life span. The prevalence of schistosomiasis in the focus was 14.3%.A densidade planorbídica, as taxas de infecção e a produção mensal de cercárias de Schistosoma mansoni por Biomphalaria glabrata, foram determinadas em foco do Barreiro de Baixo (Belo Horizonte MG, Brasil. Durante 38 meses, de 1984 a 1987, foram capturados 5.366 moluscos dentre os quais 324 (6,03% estavam infectados com o S. mansoni. O total de cercárias eliminadas foi de 5.667.312. Cada molusco eliminou em média 17.422 cercárias durante sua permanência no laboratório. A maior longevidade dos moluscos infectados foi de 218 dias. Foi observada a cura natural de 42 (12,9% dos exemplares infectados, após cerca de 130 dias de captura. A densidade planorbídica média, no foco durante esse período foi de 16,3 moluscos por conchada. A eliminação de cercárias pelos moluscos do campo foi comparada com a de exemplares criados no laboratório, infectados

  14. The role of behavior in the survival of Biomphalaria glabrata in biossays with the plant molluscicide Phytolacca dodecandra O papel do comportamento na sobrevivência de Biomphalaria glabrata submetida a bioensaios com o moluscicida vegetal Phytolacca dodecandra

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    P. Jurberg

    1988-03-01

    Full Text Available This work examines the role of behavior in the survival of Biomphalaria glabrata exposed to 25, 50 75 and 100 mgl-1 of Phytolacca dodecandra. Time-lapse cinematography was used to quantify accurately the following parameters: (a frequency of exits from the solution, (b time spent out of the solution and (c time elapsed until the first exit from the solution. These behavior patterns were statistically compared between surviving snails and those which later died. The proportion of surviving snails leaving the liquid medium was significantly higher than that of dying snails. In addition, the surviving group spent significantly more time out of the solution than the group which died, except for the 100 mgl-1 concentration. However, no significant difference was detected in the time elapsed until the first exit from the solution. It can be concluded that both the tendency to leave the P. dodecandra solutions, and the time spent out of them, contributed significantly to snail survival. Molluscicide bioassays should take into account the possibility that some behavior patterns of planorbids might contribute to the protection of the snails.Este trabalho investiga o papel do comportamento na sobrevivência de Biomphalaria glabarta exposta a 25, 50, 75 e 100 mgI-1 de Phytolacca dodecandra. Foi utilizada a técnica de cinematografia com lapso de tempo para quantificar acuradamente os seguintes parâmetros (a freqüência de saídas da solução, (b tempo de permanência fora da solução e (e tempo decorrido até a primeira saída da soluçao. Estes padrões comportamentais foram estatisticamente comparados no que se refere aos caramujos sobreviventes e aos que vieram a morrer. Dentre os camundongos que abandonaram o meio líquido, a proporção de sobreviventes foi significativamente maior que a de mortos. Além disso, um tempo significativamente maior de permanência fora da solução foi observado no grupo que sobreviveu, em relação ao grupo que veio

  15. Abundância e infecção do molusco Biomphalaria glabrata pelo Schistosoma mansoni no Estado do Rio de Janeiro, Brasil Abundance and Schistosoma mansoni infection of the snail Biomphalaria glabrata, Brazil

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    Alexandre Giovanelli

    2001-12-01

    Full Text Available OBJETIVOS: Investigar a distribuição espacial, a abundância e os índices de infecção natural de Biomphalaria glabrata, hospedeiro intermediário do Schistosoma mansoni, em localidade do Estado do Rio de Janeiro, RJ, Brasil. MÉTODOS: Na localidade de Pamparrão, município de Sumidouro, RJ, as coletas de moluscos foram realizadas bimestralmente no período de junho de 1991 a novembro de 1995. Foram estabelecidos 23 pontos de coleta ao longo do córrego Pamparrão e três de seus afluentes. Os moluscos capturados foram levados ao laboratório para diagnóstico da infecção. Para a análise dos dados, foram usados o coeficiente de Spearman (nível de 0,5% de significância e o teste de qui-quadrado. RESULTADOS: A abundância populacional de B. glabrata foi bastante variável ao longo do tempo e entre os ambientes amostrados. A maioria dos pontos de coleta apresentou correlação negativa com a pluviosidade. O afluente B destacou-se dos demais corpos d'água por apresentar taxas de infecção de B. glabrata elevadas (acima dos 25% em alguns pontos de coleta e persistentes. Foram encontrados mais moluscos infectados na estação seca do que na chuvosa (chi²=20,08; p=0,001. CONCLUSÕES: A população de moluscos foi influenciada negativamente pelo regime de chuvas, principalmente no córrego Pamparrão. A época de estiagem também parece ter favorecido a ocorrência de infecção, provavelmente devido ao menor volume de água dos córregos, o que aumentaria as chances de encontro do parasita com seu hospedeiro intermediário.OBJECTIVES: To investigate the spatial distribution, abundance and natural schistosomiasis infection levels in the snail Biomphalaria glabrata, the intermediate host of Schistosoma mansoni in an area of the State of Rio de Janeiro, Brazil. METHODS: In the Pamparrão area, Sumidouro county, RJ, Brazil, snail captures were carried out every other month from June 1991 to November 1995. There were 23 collecting sites along

  16. Résistance a la dessiccation de Biomphalaria glabrata adultes infestés par plusieurs miracidiums de Schistosoma mansoni

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    F. Lancastre

    1989-06-01

    Full Text Available Les auteurs ont soumis à 6 semaines d'anhydrobiose 1200 Biomphalaria adultes, saines, ou parasitées par 8 ± 2 miracidiums de Schistosoma mansoni depois 3 ou 12 jours, ou émettant des cercaires. Les planorbes étaient placées individuellement sur, ou dans de la terre humide, dans des boîtes closes ou aérées. La survie a été nulle chez les planorbes saines, infestées, ou déjà positives, placées dans les boîtes closes. Chez les mollusques placés dans les boîtes aérées, elle a été de 44% chez les témoins sains, et de 40,6% pour l'emsemble des infestées depuis 3 et 12 jours, avec chez ces derniers une meilleure survie lorsqu'ils étaient en surface. N n'est pas apparu de différence entre les infestations de 3 jours et de 12 jours. La mortalité et la production cercarienne sont infériéures à celles de planorbes infestées et gardées en eau. L'analyse des émissions montre une production des cercaires mâles siginificativement inférieure à celle des cercaires femelles ou mâles et femelles. Chez toutes les B. glabrata positives, les auteurs ont observé des variations périodiques dans la production des cercaires, quel que soit le sexe de celles-ci. De plus, chez les mollusques préalablement soumis à dessiccation, il existe de nombreus arrêts ou pauses dans l'émission des larves.

  17. Low genetic diversity in a snail intermediate host (Biomphalaria pfeifferi Krass, 1848) and schistosomiasis transmission in the Senegal River Basin.

    Science.gov (United States)

    Campbell, G; Noble, L R; Rollinson, D; Southgate, V R; Webster, J P; Jones, C S

    2010-01-01

    Population genetic perturbations of intermediate hosts, often a consequence of human pressure on environmental resources, can precipitate unexpectedly severe disease outbreaks. Such disturbances are set to become increasingly common following range changes concomitant with climate shifts, dwindling natural resources and major infrastructure changes such as hydroprojects. Construction of the Diama dam in the Senegal River Basin (SRB) reduced river salinity, enabling the freshwater snail intermediate host Biomphalaria pfeifferi to rapidly expand its distribution. A serious public health problem ensued, with an epidemic of intestinal schistosomiasis occurring in the previously schistosome-free Richard-Toll region within 2 years. The current study aimed to assess the population variability of B. pfeifferi in the SRB, and speculate upon its subsequent impact on host-parasite interactions following such engineered ecological change. Genetic variation at nine polymorphic microsatellite loci revealed little population differentiation in SRB snails compared with those from natural habitats in Zimbabwe, where Schistosoma mansoni transmission is much lower. 'Open' SRB habitats are associated with greater water contact, smaller population sizes and less genetic diversity, with sites downstream of Richard-Toll showing greater inter- and intrapopulation variation, concomitant with less frequent human contact. These observations may be explained by rapid expansion into pristine habitat selecting for high fecundity genotypes at the expense of schistosome resistance, presenting S. mansoni with genetically homogenous highly fecund susceptible populations around the focal point, promoting development of a highly compatible host-parasite relationship. Longitudinal study of such systems may prove important in predicting public health risks engendered by future environmental engineering projects.

  18. Toxic effects of Microgramma vacciniifolia rhizome lectin on Artemia salina, human cells, and the schistosomiasis vector Biomphalaria glabrata.

    Science.gov (United States)

    de Albuquerque, Lidiane Pereira; Pontual, Emmanuel Viana; Santana, Giselly Maria de Sá; Silva, Luanna Ribeiro Santos; Aguiar, Jaciana dos Santos; Coelho, Luana Cassandra Breitenbach Barroso; Rêgo, Moacyr Jesus Barreto de Melo; Pitta, Maira Galdino da Rocha; da Silva, Teresinha Gonçalves; Melo, Ana Maria Mendonça de Albuquerque; Napoleão, Thiago Henrique; Paiva, Patrícia Maria Guedes

    2014-10-01

    The present study evaluated the toxicity of Microgramma vacciniifolia rhizome lectin (MvRL) to Artemia salina, human tumour cell lines (larynx epidermoid carcinoma Hep-2, NCI-H292 lung mucoepidermoid carcinoma, and chronic myelocytic leukaemia K562), and normal peripheral blood mononuclear cells (PBMCs), as well as to Biomphalaria glabrata embryos and adults. MvRL was toxic to A. salina (LC50=159.9 μg/mL), and exerted cytotoxic effects on NCI-H292 cells (IC50=25.23 μg/mL). The lectin (1-100 μg/mL) did not affect the viability of K562 and Hep-2 tumour cells, as well as of PBMCs. MvRL concentration of 1, 10, and 100 μg/mL promoted malformations (mainly exogastrulation) in 7.8%, 22.5%, and 27.7% of embryos, respectively, as well as delayed embryo development in 42.0%, 69.5%, and 54.7% of embryos, respectively. MvRL at a concentration of 100 μg/mL killed B. glabrata embryos (17.7%) and adults (25%). Further, MvRL damaged B. glabrata reproductive processes, which was evidenced by observations that snails exposed to the lectin (100 μg/mL) deposited fewer eggs than those in the control group, and approximately 40% of the deposited eggs exhibited malformations. Comparison of these results with that from A. salina assay indicates that MvRL is adulticidal at the concentration range which is toxic to environment. In conclusion, the cytotoxicity of MvRL on tumour cell and absence of toxicity to normal cell indicate its potential as chemotherapeutic drug. Also, the study revealed that the lectin is able to promote deleterious effects on B. glabrata embryos at environmentally safe concentrations.

  19. Schistosoma mansoni in susceptible and resistant snail strains Biomphalaria tenagophila: in vivo tissue response and in vitro hemocyte interactions.

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    Rafael Nacif-Pimenta

    Full Text Available Schistosomiasis is a parasitic disease that is highly prevalent, especially in developing countries. Biomphalaria tenagophila is an important invertebrate host of Schistosoma mansoni in Brazil, with some strains (e.g. Cabo Frio being highly susceptible to the parasite, whereas others (e.g. Taim are completely resistant to infection. Therefore, B. tenagophila is an important research model for studying immune defense mechanisms against S. mansoni. The internal defense system (IDS of the snail comprises hemocytes and hemolymph factors acting together to recognize self from non-self molecular patterns to eliminate the threat of infection. We performed experiments to understand the cellular defenses related to the resistance and/or susceptibility of B. tenagophila to S. mansoni. During the early stages of infection, fibrous host cells of both snail strains were arranged as a thin layer surrounding the sporocysts. However, at later stages of infection, the cellular reactions in resistant snails were increasingly more intense, with thicker layers surrounding the parasites, in contrast to susceptible strains. All parasites were damaged or destroyed inside resistant snails after 10 h of infection. By contrast, parasites inside susceptible snails appeared to be morphologically healthy. We also performed experiments using isolated hemocytes from the two strains interacting with sporocysts. Hemocyte attachment started as early as 1 h after initial infection in both strains, but the killing of sporocysts was exclusive to hemocytes from the resistant strain and was time course dependent. The resistant strain was able to kill all sporocysts. In conclusion, our study revealed important aspects of the initial process of infection related to immune defense responses of strains of B. tenagophila that were resistant to S. mansoni compared with strains that were susceptible. Such information is relevant for the survival or death of the parasites and so is important

  20. Planorbidae, Lymnaeidae and Physidae of Ecuador (Mollusca: Basommatophora

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    W Lobato Paraense

    2004-06-01

    Full Text Available In the course of a trip to Ecuador I had the opportunity of collecting topotypic specimens of the following nominal species of pulmonate molluscs: Biomphalaria cousini Paraense, 1966; Planorbis equatorius Cousin, 1887; P. canonicus Cousin, 1887; Lymnaea cousini Jousseaume, 1887 and P. boetzkesi Miller, 1879. Additional findings were: Helisoma trivolvis (Say, 1817, Biomphalaria peregrina (Orbigny 1835, Drepanotrema anatinum (Orbigny, 1835, D. kermatoides (Orbigny, 1835, D. lucidum (Pfeiffer, 1839, D. surinamense (Clessin, 1884, Lymnaea columella Say, 1817 and Physa acuta Draparnaud, 1805. P. boetzkesi and P. canonicus are considered junior synonyms of Gyraulus hindsianus (Dunker, 1848 and Biomphalaria peregrina (Orbigny, 1835, respectively.

  1. Effect of the plant Azolla pinnata on survival, growth rate, fecundity and hatchability of egg-masses of Biomphalaria alexandrina snails.

    Science.gov (United States)

    Abdel Hafez, A M; Zidan, Z H; Abdel-Megeed, M I; el-Emam, M A; Ragab, F M; el-Deeb, F A

    1997-12-01

    Data indicated that Azolla pinnata plants variously reduce the growth rate of Biomphalaria alexandrina snails expressed as net increase in shell diameter (direct or indirect exposure). The plant density played an important role in this respect. The higher the plant density was the lower the growth rate and vice versa. Too, indirect exposure of newly hatched B. alexandrina resulted from exposed treated eggs reduced the growth rate of these snails. Data revealed that direct and/or indirect exposure to the abnormal high density (50,000 plants/L) resulted in complete kill of B. alexandrina snails after two weeks from continuous exposure. Snails exposed directly to Azolla at 50,000 and 25,000 plants/L failed to lay eggs. On the other hand, sanils exposed to 10,000 plants/L laid few eggs, resulted in low reproductive rate (57.94) compared with unexposed ones (110.6). The same trend of results was recorded with hatchability of Biomphalaria eggs.

  2. The molluscicidal activity of the latex of Euphorbia splendens var. hislopii on Melanoides tuberculata (Thiaridae, a snail associated with habitats of Biomphalaria glabrata (Planorbidae

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    Alexandre Giovanelli

    2001-01-01

    Full Text Available The use of the latex of Euphorbia splendens var. hislopii was considered as an effective control method for Biomphalaria glabrata in Sumidouro, Rio de Janeiro. However, the appearance and expansion of the snail Melanoides tuberculata since August 1997, with the concomitant reduction of the population of B. glabrata suggest that competitive exclusion might be taking place. Depending on the susceptibility of the thiarid to the E. splendens toxin, the natural control that is occurring could be interrupted by the employment of the latex if the planorbid were less susceptible to the toxin. The aim of this study is to investigate the molluscicidal activity of the latex on M. tuberculata. We used 420 M. tuberculata, from Sumidouro. Fourteen different latex concentrations were tested using World Health Organization general methodology. Probit analysis was used for LD90 and LD50 determination. The LD50 was 3.57 mg/l and LD90 was 6.22 mg/l. At the highest concentration (10 mg/l there was no survival. No significant differences among replicas (chi2 = 8.31; gl = 13; p > 0.05 were found. The LD90 dose for M. tuberculata was 13.8 times greater than that for B. glabrata, so that the molluscicide in the presence of the thiarid may have a synergic effect on reduction of Biomphalaria populations.

  3. A Novel Toll-Like Receptor (TLR Influences Compatibility between the Gastropod Biomphalaria glabrata, and the Digenean Trematode Schistosoma mansoni.

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    Emmanuel A Pila

    2016-03-01

    Full Text Available Schistosomiasis, a devastating disease caused by parasitic flatworms of the genus Schistosoma, affects over 260 million people worldwide especially in tropical and sub-tropical regions. Schistosomes must undergo their larval development within specific species of snail intermediate hosts, a trait that is shared among almost all digenean trematodes. This unique and long-standing host-parasite relationship presents an opportunity to study both the importance of conserved immunological features in novel immunological roles, as well as new immunological adaptations that have arisen to combat a very specific type of immunological challenge. While it is well supported that the snail immune response is important for protecting against schistosome infection, very few specific snail immune factors have been identified and even fewer have been functionally characterized. Here, we provide the first functional report of a snail Toll-like receptor, which we demonstrate as playing an important role in the cellular immune response of the snail Biomphalaria glabrata following challenge with Schistosoma mansoni. This TLR (BgTLR was identified as part of a peptide screen of snail immune cell surface proteins that differed in abundance between B. glabrata snails that differ in their compatibility phenotype to challenge by S. mansoni. The S. mansoni-resistant strain of B. glabrata (BS-90 displayed higher levels of BgTLR compared to the susceptible (M-line strain. Transcript expression of BgTLR was found to be very responsive in BS-90 snails when challenged with S. mansoni, increasing 27 fold relative to β-actin (non-immune control gene; whereas expression in susceptible M-line snails was not significantly increased. Knockdown of BgTLR in BS-90 snails via targeted siRNA oligonucleotides was confirmed using a specific anti-BgTLR antibody and resulted in a significant alteration of the resistant phenotype, yielding patent infections in 43% of the normally resistant

  4. 大竹蛏5个野生群体遗传多样性的微卫星分析%Microsatellite analysis of genetic diversity of five wild populations of Solen grandis (Dunker)

    Institute of Scientific and Technical Information of China (English)

    张志伟; 张雨; 陈爱华; 张志勇; 陆勤勤; 张朝晖; 姚国兴; 蔡永祥; 吴杨平; 曹奕

    2015-01-01

    The grand jackknife clam Solen grandis (Dunker, 1861) is a commercial marine bivalve that is found in coastal waters of China, Japan, and Korea from the shallow subtidal to depths of 20 m. It has high nutritive and medical value according to traditional Chinese medicine. In addition, it is adaptable and has high growth rates and great market potential. Currently, this clam is only available from natural sources. Over the last few decades, however, overfishing and environmental pollution have caused dramatic declines in natural stocks of S. grandis, and production is low and unstable. Fortunately, methods of artificial breeding and cultivation of the jackknife clam are developing. Previous studies on S. grandis focused primarily on morphological and ecological characteristics, allozyme analysis, and evalua-tion of its nutrition components. Little is known about the molecular ecology of S. grandis or its genetic background. Thus, it is important to evaluate genetic differences among populations along the coast of China. In this study, 14 mi-crosatellite DNA markers were used to examine the genetic diversity and differentiation among five wild populations of the grand jackknife clam. A total of 150 samples were collected from Dandong (DD) in Liaoning Province, Qinhuang-dao (QHD) in Hebei Province, Rizhao (RZ) in Shandong Province, Lyusi (LS) in Jiangsu Province, and Beihai (BH) in Guangxi Province. Comparisons of 199 alleles among the five populations showed that, in the fourteen loci, polymor-phism information content (PIC)values ranged from 0.696 to 0.853 with high polymorphism. The number of alleles ranged from 8 to 22 and the average number (AM) and richness(AR) of alleles were 14.2 and 11.05, respectively. Ex-pected (He) and observed heterozygosity (Ho) ranged 0.769–0.826 and 0.809–0.858, respectively, suggesting high levels of genetic diversity in all populations. Only the Sg16 locus in the DD population deviated significantly from Hardy-Weinberg equilibrium

  5. Implications of water hardness in ecotoxicological assessments for water quality regulatory purposes: a case study with the aquatic snail Biomphalaria glabrata (Say, 1818

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    EC Oliveira-Filho

    Full Text Available Water hardness is a property depending on the presence of alkaline earth metals, mainly calcium and magnesium. Among the strategies for water quality monitoring, ecotoxicological assays are performed to minimize impacts and classify water bodies. For these laboratory evaluations parameters are previously defined in the guidelines, including water hardness for both cultivation and testing medium. The present work was performed to evaluate the effects of different levels of water hardness on the survival and reproduction of the freshwater snail Biomphalaria glabrata and discuss the influence of natural water hardness on the results of ecotoxicological tests with these environmental samples. Comparing the groups it was possible to observe that those maintained in waters with least hardness had lower reproductive success, while the groups maintained in highest hardness showed better reproduction. These data show that waters with low hardness make the reproduction of the snail B. glabrata unfeasible, and this reveal a problem for ecotoxicity assays using natural water samples.

  6. Aspectos ultraestruturais de hemócitos de Biomphalaria glabrata Say (1818 (Gastropoda: Planorbidae analisados sob microscopia eletrônica de transmissão Ultrastructural aspects of hemocytes from Biomphalaria glabrata Say (1818 (Gastropoda: Planorbidae analysed with transmission eletronic microscopy

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    Marco Antonio Vasconcelos Santos

    2009-09-01

    Full Text Available Os hemócitos do caramujo Biomphalaria glabrata, um importante transmissor do trematódeo Schistosoma mansoni no Brasil, foram coletados de especimens na região Bragantina, localizada a oeste do estado do Pará. Os hemócitos foram examinados por meio de microscopia eletrônica de transmissão. As células foram fixadas pelo método de rotina com o uso do tampão PHEM (PIPES, HEPES, EGTA e Magnésio. Foram descritos os aspectos ultra-estruturais celulares como inclusões citoplasmáticas limitadas por membranas, mitocôndrias, retículos endoplasmáticos e outros. As observações mostram que esse tampão possui a propriedade de preservação do citoesqueleto celular, apresentando bons resultados na preservação das estruturas dos hemócitos e suas organelas.The blood cells of the pulmonate snail Biomphalaria glabrata from the region of Bragantina in the state of Pará, an important vector of the trematode Schistosoma mansoni in Brazil, were collected and fixed by routine method with PHEM buffer and examined with transmission electron microscopy. Ultrastructural cellular aspects like cytoplasmic inclusions, mitochondrion, vesicles and others organelles are described. The buffer used resulted in good preservations of the hemocytes and their organelles.

  7. Comportamento de Biomphalaria glabrata (Say, 1818 como critério de toxicidade em ensaios biológicos com moluscicidas Behavior of Biomphalaria glabrata (Say, 1818 as a parameter of toxicity in biological assays with molluscicides

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    Otávio S. Pieri

    1981-06-01

    Full Text Available Visando à aplicação sistemática de parâmetros comportamentais como indicadores da ação tóxica de moluscicidas empregados no combate aos hospedeiros intermediários do Schistosoma mansoni, um procedimento para avaliação quantitativa do efeito de dose sobre o comprotamento de Biomphalaria glabrata foi desenvolvido, com base no paradigma recomendado pela O.M.S. para ensaios biológicos e envolvendo registro comportamental por cenematografia ocm lapso de tempo: caramujos com 5 7/8 ± 1/8 giros eram subemtidos a diferentes concentrações subletais de sulfato de cobre durante 24 horas e em seguida transferidos para recuperação em água destilada desionizada; a partir da análise dos registros foram computados (a a freqüência total de subidas à superfície por indivíduo, (b a frqüência total de saídas da água por indivíduo e (c a proporção média de indivíduos no terço superior do recipiente de teste. O método Litchfield-Wilcoxon foi empregaod para determinação de índices de referência (denominados "concentrações de efieto comportamental de 50%" ou CEC50 em relação a cada parâmetro, e os valores obtidos - (a 0,010, (b 0,006 e (c 0,029 ppm de cobre - não só evidenciaram a exeqüibilidade da aplicação sistemática de critérios comportamentais de toxidade, como se revelaram capazes de detectar o efieto tóxico do produto em concentrações muito infereiores às obtidas nas determinações convencionais de letalidade. Os dados também mostraram alterações na atividade dos caramujos em decorrência do ciclo de iluminação dia-noite. Embora o esclarecimento dos aspectos etológicos envolvidos no problema do controle químico do vetor dependa da análise das relações entre o indivíduo e seu ambiente natural, estudos de laboratório com mensurações acuradas de parâmetros relacionados a comportamentos de proteção podem fornecer subsídios relevantes a respeito.The possibility of using reliable behavioural

  8. Content Determination of Isoorientin in Different Parts of Tibetan Medicine Gentiana straminea Maxim. Based on RP-HPLC Method%基于RP-HPLC法的藏药麻花艽不同部位异荭草素含量的测定

    Institute of Scientific and Technical Information of China (English)

    聂颖杰; 林鹏程

    2010-01-01

    [目的]建立麻花艽(Gentiana straminea Maxim.)不同部位中异荭草素的RP-HPLC检测方法.[方法]色谱条件为:Hypersil ODS柱(4.6 mm×250.0 mm,5 μm),以40%甲醇-水溶液(含0.02 %磷酸)等度洗脱,流速1 ml/min,柱温35 ℃,检测波长254 nm.[结果]在设定的色谱条件下,异荭草素与其他组分达到基线分离,线性范围为0.089 9~0.539.0 μg,r= 0.999 9.加标回收率为99.7%,RSD为0.49%.[结论]方法快速、准确,结果可靠.

  9. Assessment of the impact of changes in temperature in Biomphalaria glabrata (Say, 1818 melanic and albino variants infected with Schistosoma mansoni (Sambon, 1907

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    E. A. F. Camargo

    Full Text Available Abstract Fluctuations in population density of planorbid hosts of S. mansoni are influenced by climatic factors. The knowledge about interference from changes in water temperature in these populations is an important aspect of the epidemiology of schistosomiasis. In this experiment, it is explored the influence of different temperatures on the development of Schistosoma mansoni in Biomphalaria glabrata melanic and albino variants. The results indicated an intrinsic relationship between temperature and development of the parasite in the intramollusc phase, independent of the pigmentation of the mantle of the molluscs. The higher the temperature, the shorter the period necessary for the development of the parasite was while the higher the mortality of infected mollusks. It is concluded that, in the presence of climate change, the increasement of temperature in cold and flooded regions may encourage the establishment of new foci of transmission of schistosomiasis by changing the geographic extent and extending the epidemiological transmission potential. In warm climates, higher temperatures, however, could compromise the transmission of the disease because of biological stress suffered by parasite and host. Under these conditions, it can result in the death of the parasite or a change in their ability to infect new host species of molluscs in new areas. Mantle pigmentation patterns in molluscs have not shown significant interference in the development of the parasite.

  10. Physiological changes in Biomphalaria glabrata say, 1818 (Pulmonata: Planorbidae caused by sub-lethal concentrations of the latex of Euphorbia splendens var. hislopii N.E.B (Euphorbiaceae

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    Clélia Christina Mello-Silva

    2006-02-01

    Full Text Available Molluscides have been used as one of the strategies to control schistosomiasis. Many plant extracts with molluscidal effects have been tested, but the action of the latex of Euphorbia splendens var. hislopii is considered the most promising because it meets the recommendations of the World Health Organization (WHO. The objective of this study was to determine the lethal dose and identify the effects of the different doses of latex of E. splendens var. hislopii on the physiology of Biomphalaria glabrata submitted to treatment for 24 h. The concentrations of glucose, uric acid and total proteins in the hemolymph and of glycogen in the digestive gland and cephalopodal mass were determined. The LD50 value was 1 mg/l. The highest escape index was found to be at a concentration of 0.6 mg/l. The results showed that the latex of E. splendens var. hislopii caused a sharp reduction in the reserves of glycogen in the digestive gland and elevation of the protein content in the hemolymph of B. glabrata.

  11. Controle biológico de Biomphalaria glabrata (Say, 1818 através de Tilapia nilotica (Hasselquist, 1757, em laboratório (Pulmonata, Planorbidae. Pisces, Cichlidae

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    Roberto Milward de Andrade

    1982-12-01

    Full Text Available O peixe cichdeo Tilapia nilotica (Hasse/quist, 1757 I = Sarotherodon niloticus Linnaeus, 1758 foi capaz de impedir o crescimento de 4 populações de 20 espécimens (14-16 mm de diâmetro de Biomphalaria glabrata (Say, 1818, mantidas em aquários de vidro, durante cinco semanas, em laboratório. No Aquário nº 1 foi introduzido um alevino com 55 mm de comprimento (não computada a nadadeira caudal; no de nº 2, um com 63 mm; no de nº 3, dois alevinos: com 40 e 46 mm, respectivamente; e, finalmente, no de nº 4, três espécimens: com 38,39 e 42 mm, respectivamente. Os peixes destruíram as desovas dos planorbíneos depositadas nas paredes de vidro dos aquários - impedindo, assim, as eclosões e, consequentemente, o aumento das quatro populações em estudo. Reversamente, quando retirados, as populações de planorbíneos cresceram em número. Não obstante, salienta-se a necessidade de investigações de campo, afim de avaliar a atividade predatória daquele ciclídeo em condições naturais.

  12. Effect of Niclosamide (Bayluscide WP 70 (R, Anacardium occidentale hexane extract and Euphorbia splendens latex on behavior of Biomphalaria glabrata (Say, 1818, under laboratory conditions

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    Pedro Jurberg

    1995-04-01

    Full Text Available The repellent effect of the molluscicides Niclosamide (Bayluscide WP 70 (R, Anacardium occidentale and the latex of Euphorbia splendens on Biomphalaria glabrata was observed through the investigation of the occurrence of escape behavior among molluscs that were exposed to dosages lower than the LD 50. The total number of individuals out of water among the surviving snails in the control group provided a "Natural Escape Index". The comparison between this total and the total number of surviving snails in each group exposed to the different dosages of the molluscicides after 24 hr provided the "Molluscicide Escape Index" and the detection of a "Repellency Range" to these snails. The escape indexes for Niclosamide, A. occidentale and E. splendens were 10, 6.22 and 6.44 respectively. Repellency occurred at the following concentration ranges: 0.01, 0.02 and 0.03 ppm Bayluscide, 0.1, 0.2 and 0.3 ppm A. occidentale and 0.05, 0.10, 0.15 and 0.20 ppm E. splendens. The Natural Escape Index obtained in the control group was zero.

  13. Distribution and Schistosoma mansoni infection of Biomphalaria glabrata in different habitats in a rural area in the Jequitinhonha Valley, Minas Gerais, Brazil: environmental and epidemiological aspects

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    Helmut Kloos

    2004-11-01

    Full Text Available This paper examines the distribution and infection of Biomphalaria glabrata with Schistosoma mansoni in all aquatic snail habitats in a rural area in the state of Minas Gerais, Brazil, in relation to physico/biotic and behavioral factors. Snail and environmental surveys were carried out semi-annually between July 2001 and November 2002 at 106 sites. Collected snails were examined in the laboratory for infection. B. glabrata densities were highest in overflow ponds, irrigation ponds, springs, canals and wells, and lowest in fishponds and water tanks. Snail densities were higher during the hot, rainy season except for streams and canals and were statistically associated with the presence of fish, pollution, and vegetation density. Tilapia fish and an unidentified Diptera larva were found to be predators of B. glabrata but ducks were not. Twenty-four of the 25 infected snails were collected in 2001(1.4% infection rate and only one in 2002, after mass chemotherapy. The occurrence of B. glabrata in all 11 snail habitats both at and away from water contact sites studied indicates widespread risk of human infection in the study area. In spite of the strong association between B. glabrata and tilapia in fishponds we do not recommend its use in schistosomiasis control for ecological reasons and its relative inefficiency in streams and dams.

  14. Impact of the age of Biomphalaria alexandrina snails on Schistosoma mansoni transmission: modulation of the genetic outcome and the internal defence system of the snail

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    Iman Fathy Abou-El-Naga

    2015-08-01

    Full Text Available Of the approximately 34 identified Biomphalariaspecies,Biomphalaria alexandrinarepresents the intermediate host of Schistosoma mansoniin Egypt. Using parasitological and SOD1 enzyme assay, this study aimed to elucidate the impact of the age of B. alexandrinasnails on their genetic variability and internal defence against S. mansoniinfection. Susceptible and resistant snails were reared individually for self-reproduction; four subgroups of their progeny were used in experiment. The young susceptible subgroup showed the highest infection rate, the shortest pre-patent period, the highest total cercarial production, the highest mortality rate and the lowest SOD1 activity. Among the young and adult susceptible subgroups, 8% and 26% were found to be resistant, indicating the inheritance of resistance alleles from parents. The adult resistant subgroup, however, contained only resistant snails and showed the highest enzyme activity. The complex interaction between snail age, genetic background and internal defence resulted in great variability in compatibility patterns, with the highest significant difference between young susceptible and adult resistant snails. The results demonstrate that resistance alleles function to a greater degree in adults, with higher SOD1 activity and provide potential implications for Biomphalariacontrol. The identification of the most susceptible snail age enables determination of the best timing for applying molluscicides. Moreover, adult resistant snails could be beneficial in biological snail control.

  15. The Influence of Self-fertilization performance and Copulation Behaviour in Reproduction by Cross-fertilization in Groups of Biomphalaria tenagophila (Mollusca, Planorbidae

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    Freitas June Springer de

    1997-01-01

    Full Text Available The following hypotheses were tested for groups of simultaneous hermaphrodites Biomphalaria tenagophila: (a snails that have low reproductive success during the process of self-fertilization do not increase their reproductive success after the end of grouping; (b the copulation behaviour and the presence of one snail whose eggs have a low viability rate influence the partner's reproductive success by cross-fertilization. Groups were constituted by a homozygous pigmented snail and two albinos: one with a viability rate higher than 70% ("good reproducers" and the other less than 10% ("bad reproducers". All pigmented snails had viability rates higher than 70%. The "good" and "bad" reproducer albino snails had similar copulation behaviour. However, after the end of grouping, the "bad reproducers" continued to have viability rates less than 10% over 30 days. In 100% of the cases that pigmented snails copulated (performing either a male role or simultaneously male and female roles exclusively with "good" reproducer albinos, they presented high reproductive success (producing, on average of 8.4 pigmented embryos/egg-mass. However, in 100% of the cases that pigmented snails copulated with both partners, the "good" reproducer albino snails produced none or very few embryos (the highest average was 2.2 pigmented embryos/egg-mass. Therefore, the production of viable embryos by cross-fertilization was more influenced by self-fertilization performance than by copulation behaviour. The presence of a snail whose eggs have a low viability rate could decrease their partners reproductive success

  16. Activation of anaerobic metabolism in Biomphalaria glabrata (Mollusca: Gastropoda) experimentally infected by Angiostrongylus cantonensis (Nematoda, Metastrongylidae) by high-performance liquid chromatography.

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    Tunholi-Alves, Vinícius Menezes; Tunholi, Victor Menezes; Castro, Rosane N; Sant'Ana, Luiza D'Oliveira; Santos-Amaral, Luciana; de Oliveira, Ana Paula Martins; Garcia, Juberlan; Thiengo, Silvana Carvalho; Pinheiro, Jairo; Maldonado, Arnaldo

    2014-02-01

    The activity of lactate dehydrogenase and the concentrations of glucose in the hemolymph and of glycogen in the digestive gland and cephalopedal mass of Biomphalaria glabrata experimentally infected with Angiostrongylus cantonensis were evaluated. Additionally, high performance liquid chromatography (HPLC) was used to determine the hemolymph concentrations of some carboxylic acids (oxalic, piruvic, lactic and succinic). After one, two and three weeks of infection, the snails were dissected to collect the hemolymph and separate the tissues. A significant reduction of the levels of glucose in the hemolymph was observed as of the first week of infection in relation to the control group. The lactate dehydrogenase activity of the infected group was significantly higher than the average of the control group. This increase was accompanied by a reduction of the levels of piruvic acid and an increase in the levels of lactic acid in the hemolymph of the parasited snails, confirming the acceleration of the anaerobic metabolism, necessary for the host to obtain energy and maintain its redox balance. In parallel, there was a decrease in the glycogen content of the storage tissues, with that reduction being significantly greater in the cephalopedal mass than the digestive gland, demonstrating that in this interaction system, the mobilization of glycogen was not sufficient to maintain and reestablish the normal glycemia of the infected snails.

  17. Nitric oxide production by Biomphalaria glabrata haemocytes: effects of Schistosoma mansoni ESPs and regulation through the extracellular signal-regulated kinase pathway

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    Kirk Ruth S

    2009-04-01

    Full Text Available Abstract Background Schistosoma mansoni uses Biomphalaria glabrata as an intermediate host during its complex life cycle. In the snail, the parasite initially transforms from a miracidium into a mother sporocyst and during this process excretory-secretory products (ESPs are released. Nitric oxide (NO and its reactive intermediates play an important role in host defence responses against pathogens. This study therefore aimed to determine the effects of S. mansoni ESPs on NO production in defence cells (haemocytes from schistosome-susceptible and schistosome-resistant B. glabrata strains. As S. mansoni ESPs have previously been shown to inhibit extracellular signal-regulated kinase (ERK phosphorylation (activation in haemocytes from susceptible, but not resistant, B. glabrata the regulation of NO output by ERK in these cells was also investigated. Results Haemocytes from resistant snails challenged with S. mansoni ESPs (20 μg/ml over 5 h displayed an increase in NO production that was 3.3 times greater than that observed for unchallenged haemocytes; lower concentrations of ESPs (0.1–10 μg/ml did not significantly increase NO output. In contrast, haemocytes from susceptible snails showed no significant change in NO output following challenge with ESPs at any concentration used (0.1–20 μg/ml. Western blotting revealed that U0126 (1 μM or 10 μM blocked the phosphorylation (activation status of ERK in haemocytes from both snail strains. Inhibition of ERK signalling by U0126 attenuated considerably intracellular NO production in haemocytes from both susceptible and resistant B. glabrata strains, identifying ERK as a key regulator of NO output in these cells. Conclusion S. mansoni ESPs differentially influence intracellular NO levels in susceptible and resistant B. glabrata haemocytes, possibly through modulation of the ERK signalling pathway. Such effects might facilitate survival of S. mansoni in its intermediate host.

  18. Altered Gene Expression in the Schistosome-Transmitting Snail Biomphalaria glabrata following Exposure to Niclosamide, the Active Ingredient in the Widely Used Molluscicide Bayluscide.

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    Si-Ming Zhang

    Full Text Available In view of the call by the World Health Organization (WHO for elimination of schistosomiasis as a public health problem by 2025, use of molluscicides in snail control to supplement chemotherapy-based control efforts is likely to increase in the coming years. The mechanisms of action of niclosamide, the active ingredient in the most widely used molluscicides, remain largely unknown. A better understanding of its toxicology at the molecular level will both improve our knowledge of snail biology and may offer valuable insights into the development of better chemical control methods for snails. We used a recently developed Biomphalaria glabrata oligonucleotide microarray (31K features to investigate the effect of sublethal exposure to niclosamide on the transcriptional responses of the snail B. glabrata relative to untreated snails. Most of the genes highly upregulated following exposure of snails to niclosamide are involved in biotransformation of xenobiotics, including genes encoding cytochrome P450s (CYP, glutathione S-transferases (GST, and drug transporters, notably multi-drug resistance protein (efflux transporter and solute linked carrier (influx transporter. Niclosamide also induced stress responses. Specifically, six heat shock protein (HSP genes from three super-families (HSP20, HSP40 and HSP70 were upregulated. Genes encoding ADP-ribosylation factor (ARF, cAMP response element-binding protein (CREB and coatomer, all of which are involved in vesicle trafficking in the Golgi of mammalian cells, were also upregulated. Lastly, a hemoglobin gene was downregulated, suggesting niclosamide may affect oxygen transport. Our results show that snails mount substantial responses to sublethal concentrations of niclosamide, at least some of which appear to be protective. The topic of how niclosamide's lethality at higher concentrations is determined requires further study. Given that niclosamide has also been used as an anthelmintic drug for decades and

  19. The molluscicidal activity of niclosamide (Bayluscide WP70® on Melanoides tuberculata (Thiaridae, a snail associated with habitats of Biomphalaria glabrata (Planorbidae

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    Alexandre Giovanelli

    2002-07-01

    Full Text Available The aim of this study was to determine the toxicity of niclosamide (Bayluscide ® on Melanoides tuberculata and Biomphalaria glabrata under laboratory conditions. The latter species is the intermediate host of Schistosoma mansoni (Sambon 1917. M. tuberculata was successfully used as competitor of B. glabrata in biological control programs in French West Indies. Both molluscicide and biological control using M. tuberculata have proved to be successful in reducing the population density of B. glabrata. The associated use of molluscicide in this area would be an effective measure if M. tuberculata were less susceptibility to the molluscicide than B. glabrata. Three hundreds individuals each of B. glabrata and of M. tuberculata, collected in Sumidouro, State of Rio de Janeiro, were used in the experiment. The molluscs were exposed to 14 different concentrations of niclosamide as recommended by the World Health Organization. Probit analysis was used to determine the LC 50 and LC 90. The LC 50 and LC 90 values for B. glabrata were 0.077 mg/l and 0.175 mg/l, respectively and the LC 50 and LC 90 values for M. tuberculata were 0.082 mg/l and 0.221 mg/l respectively. As the lethal concentrations of niclosamide were approximately the same to both species, this could be a disadvantage when controlling B. glabrata with niclosamide in an area of M. tuberculata occurrence. It migth therefore be preferable to utilize the latex extracted from the Euphorbia splendens, which presented a much higher efficiency for B. glabrata than to M. tuberculata.

  20. Alterations in the fatty acid profile, antioxidant enzymes and protein pattern of Biomphalaria alexandrina snails exposed to the pesticides diazinon and profenfos.

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    Bakry, Fayez A; El-Hommossany, Karem; Abd El-Atti, Mahmoud; Ismail, Somaya M

    2016-04-01

    The use of pesticides is widespread in agricultural activities. These pesticides may contaminate the irrigation and drainage systems during agriculture activities and pests' control and then negatively affect the biotic and a biotic component of the polluted water courses. The present study aimed to evaluate the effect of the pesticides diazinon and profenfos on some biological activities of Biomphalaria alexandrina snails such as fatty acid profile, some antioxidant enzymes (thioredoxin reductase (TrxR), sorbitol dehydrogenase (SDH), superoxide dismutase (SOD), catalase (CAT) as well as glutathione reductase (GR) and lipid peroxidation (LP)) and protein patterns in snails' tissues exposed for 4 weeks to LC10 of diazinon and profenfos. The results showed that the two pesticides caused considerable reduction in survival rates and egg production of treated snails. Identification of fatty acid composition in snail tissues treated with diazinon and profenfos pesticides was carried out using gas-liquid chromatography (GLC). The results declared alteration in fatty acid profile, fluctuation in percentage of long chain and short chain fatty acid contributions either saturated or unsaturated ones, and a decrease in total lipid content in tissues of snails treated with these pesticides. The data demonstrate that there was a significant inhibition in the activities of tissues SOD, CAT, glutathione reductase (GR), TrxR, and SDH in tissues of treated snails, while a significant elevation was detected in LP as compared to the normal control. On the other hand, the electrophoretic pattern of total protein showed differences in number and molecular weights of protein bands due to the treatment of snails. It was concluded that the residues of diazinon and profenfos pesticides in aquatic environments have toxic effects onB. alexandrina snails.

  1. Resistência de cepa de Biomphalaria tenagophila, originária de Londrina (Paraná, Brasil à infecção por duas cepas de Schistosoma mansoni

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    Pedro P. Chieffi

    1975-08-01

    Full Text Available Exemplares de Biomphalaria tenagophila, originários de Londrina, mostraram-se resistentes à infecção por cepa simpátrica de Schistosoma mansoni e por cepa originária de Belo Horizonte (MG. Variando-se o diâmetro e a idade dos caramujos submetidos à infecção e aumentando-se o número de miracidios a que cada caramujo foi exposto, não se conseguiu obter cercárias de S. mansoni, 70 dias após a tentativa de infecção.Strains of Biomphalaria tenagophila from Londrina showed complete resistence to infection with Schistosoma mansoni, when the snails were exposed to the sympatric strain of the trematode or to the strain from Belo Horizonte, Minas Gerais State. The resistence has been retained even when the diameter of the shell of the snails and the number of miracidia used to infect each snail, were altered.

  2. Biomphalaria glabrata transcriptome: cDNA microarray profiling identifies resistant- and susceptible-specific gene expression in haemocytes from snail strains exposed to Schistosoma mansoni

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    Rollinson David

    2008-12-01

    Full Text Available Abstract Background Biomphalaria glabrata is an intermediate snail host for Schistosoma mansoni, one of the important schistosomes infecting man. B. glabrata/S. mansoni provides a useful model system for investigating the intimate interactions between host and parasite. Examining differential gene expression between S. mansoni-exposed schistosome-resistant and susceptible snail lines will identify genes and pathways that may be involved in snail defences. Results We have developed a 2053 element cDNA microarray for B. glabrata containing clones from ORESTES (Open Reading frame ESTs libraries, suppression subtractive hybridization (SSH libraries and clones identified in previous expression studies. Snail haemocyte RNA, extracted from parasite-challenged resistant and susceptible snails, 2 to 24 h post-exposure to S. mansoni, was hybridized to the custom made cDNA microarray and 98 differentially expressed genes or gene clusters were identified, 94 resistant-associated and 4 susceptible-associated. Quantitative PCR analysis verified the cDNA microarray results for representative transcripts. Differentially expressed genes were annotated and clustered using gene ontology (GO terminology and Kyoto Encyclopaedia of Genes and Genomes (KEGG pathway analysis. 61% of the identified differentially expressed genes have no known function including the 4 susceptible strain-specific transcripts. Resistant strain-specific expression of genes implicated in innate immunity of invertebrates was identified, including hydrolytic enzymes such as cathepsin L, a cysteine proteinase involved in lysis of phagocytosed particles; metabolic enzymes such as ornithine decarboxylase, the rate-limiting enzyme in the production of polyamines, important in inflammation and infection processes, as well as scavenging damaging free radicals produced during production of reactive oxygen species; stress response genes such as HSP70; proteins involved in signalling, such as importin 7

  3. The effect of increasing water temperatures on Schistosoma mansoni transmission and Biomphalaria pfeifferi population dynamics: an agent-based modelling study.

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    Nicky McCreesh

    Full Text Available There is increasing interest in the control and elimination of schistosomiasis. Little is known, however, about the likely effects of increasing water-body temperatures on transmission.We have developed an agent-based model of the temperature-sensitive stages of the Schistosoma and intermediate host snail life-cycles, parameterised using data from S. mansoni and Biomphalaria pfeifferi laboratory and field-based observations. Infection risk is calculated as the number of cercariae in the model, adjusted for their probability of causing infection.The number of snails in the model is approximately constant between 15-31°C. Outside this range, snail numbers drop sharply, and the snail population cannot survive outside the range 14-32°C. Mean snail generation time decreases with increasing temperature from 176 days at 14°C to 46 days at 26°C. Human infection risk is highest between 16-18°C and 1pm and 6-10pm in calm water, and 20-25°C and 12-4pm in flowing water. Infection risk increases sharply when temperatures increase above the minimum necessary for sustained transmission.The model suggests that, in areas where S. mansoni is already endemic, warming of the water at transmission sites will have differential effects on both snails and parasites depending on abiotic properties of the water-body. Snail generation times will decrease in most areas, meaning that snail populations will recover faster from natural population reductions and from snail-control efforts. We suggest a link between the ecological properties of transmission sites and infection risk which could significantly affect the outcomes of interventions designed to alter water contact behaviour--proposing that such interventions are more likely to reduce infection levels at river locations than lakes, where infection risk remains high for longer. In cooler areas where snails are currently found, increasing temperatures may significantly increase infection risk, potentially leading

  4. Freshwater snails and Schistosomiasis mansoni in the state of Rio de Janeiro, Brazil: III - Baixadas Mesoregion

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    Silvana C Thiengo

    2002-10-01

    Full Text Available In this paper, the third of a series dealing with the survey of freshwater gastropods of the state of Rio de Janeiro, the results of collections carried out in the Mesoregion Baixadas from 2000 to 2002 are presented. Twenty-two species, belonging to seven families, were found. As to the snail intermediate hosts of Schistosoma mansoni, the most frequent species was Biomphalaria tenagophila besides some new findings of Biomphalaria straminea. No specimens were found harboring larval forms of S. mansoni although different kinds of cercariae had been observed.

  5. Effects of Different Levels of Echinostoma caproni Miracidial Dose on Glucose and Maltose Composition of Biomphalaria glabrata Snails as Determined by High Performance Thin-Layer Chromatography-Densitometry

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    Dolcie DeGrandchamp

    2015-04-01

    Full Text Available The effects of 5, 25, and 40 Echinostoma caproni miracidia on the sugar content of young adult and mature adult Biomphalaria glabrata were studied using high performance thin layer chromatography (HPTLC-densitometry. Analysis was done on the snail’s digestive gland gonad complex (DGG at two and four weeks postmiracidial exposure. The sugars were extracted from the DGG using 70% ethanol and analyzed on silica gel HPTLC plates with a preadsorbent zone using 1-butanol-glacial acetic acid-diethyl ether-deionized water (27:18:5:3 mobile phase. The separated bands were then detected using alpha-naphthol-sulfuric reagent and quantified by densitometry at 515 nm. Significant differences were found in the maltose content between two and four weeks post exposure for both age groups. Additionally, significantly lower maltose and glucose levels were observed in the high exposure groups of both ages.

  6. A comparative parasitologic study on Biomphalaria glabrata snail and C3H/He mice infected with human and murine isolates of Schistosoma mansoni derived from Sumidouro, Rio de Janeiro, Brazil

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    Nilcéa Freire

    2003-09-01

    Full Text Available Experiments were carried out to analyze the biological characteristics of two sympatric isolates of Schistosoma mansoni derived from humans and murines in a low endemic transmission area (Sumidouro county, state of Rio de Janeiro, Brazil. Sympatric reared-laboratory Biomphalaria glabrata and C3H/He mice were used as experimental hosts. Parameters assessed comprised: precercarial period, infectivity and mortality (snails, prepatent period, infectivity (percentage of cercariae maturation into adult worm and intestinal egg count (mice. The murine isolate showed a shorter precercarial period and higher infectivity than human isolate (p 0.05. These data suggest that both isolates are local sub-populations, providing support for the hypotheses that in a same biotope mixed populations or sub-populations circulate among their main host (human beings and/or rodent as an anfixenous infection.

  7. African schistosomiasis in mainland China: risk of transmission and countermeasures to tackle the risk

    OpenAIRE

    Wang, Wei; Liang, You-Sheng; Hong, Qing-Biao; Dai, Jian-Rong

    2013-01-01

    Schistosomiasis is a major disease of public health importance in humans occurring in 76 countries of the tropics and sub-tropics. In China, schistosomiasis japonica is one of the highest priorities in communicable disease control defined by the central government. Since 1970s, the habitats of Biomphalaria straminea, an intermediate host of Schistosoma mansoni in South America, have been identified in Hong Kong Special Administrative Region and Shenzhen city, Guangdong province of China. With...

  8. Avaliação da atividade tóxica em Artemia salina e Biomphalaria glabrata de extratos de quatro espécies do gênero Eleocharis (Cyperaceae

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    A.L.T.G. Ruiz

    2005-06-01

    Full Text Available O gênero Eleocharis R. Br. compreende cerca de 200 espécies, ocorrendo em ambientes úmidos tais como brejos e margens de rios e lagos. Procurando novos agentes moluscicidas, os extratos de Eleocharis acutangula (Roxb. Schult., Eleocharis interstincta (Vahl Roem. & Schult., Eleocharis maculosa (Vahl Roem. & Schult. e Eleocharis sellowiana Kunth foram testados para atividade moluscicida, contra caramujos adultos e desovas, e toxicidade (ensaio de letalidade com Artemia salina. O extrato hexânico de Eleocharis acutangula (parte subterrânea fresca foi ativo contra Artemia salina (CL50 = 476,00 mg/mL, enquanto os demais extratos apresentaram CL50 >> 10³ mg/mL, sugerindo baixa toxicidade. O extrato hidro-etanólico de Eleocharis sellowiana (parte subterrânea fresca foi ativo contra desovas de Biomphalaria glabrata (CL50 = 24,27 mg/mL mas inativo contra indivíduos adultos. Os demais extratos testados não apresentaram atividade moluscicida.

  9. Characterization of the Life Cycle of a Fish Eye Fluke, Austrodiplostomum ostrowskiae (Digenea: Diplostomidae), with Notes on Two Other Diplostomids Infecting Biomphalaria havanensis (Mollusca: Planorbidae) from Catfish Aquaculture Ponds in Mississippi, USA.

    Science.gov (United States)

    Rosser, Thomas G; Alberson, Neely R; Khoo, Lester H; Woodyard, Ethan T; Pote, Linda M; Griffin, Matt J

    2016-04-01

    Ocular diplostomiasis is caused by trematode species in the family Diplostomidae, specifically those in the genera Austrodiplostomum, Diplostomum, and Tylodelphys. Diplostomid trematodes are globally distributed parasites of fish. Heavy infections of diplostomids that parasitize the eyes of fish can result in acute mortality while chronic infections are often characterized by impaired vision or blindness. In the southeastern United States, commercial catfish production is threatened by piscivorous birds and the many trematode species that parasitize them. The life cycles typically involve a piscivorous avian definitive host, a mollusk first intermediate host, and a fish second intermediate host. A survey of parasites infecting the snail host Biomphalaria havanensis (= B. obstructa ) in catfish production ponds was undertaken. Snails were collected from 2 separate ponds during the summer of 2014 and observed for the release of trematode cercariae. A total of 1,740 snails were collected. Three distinct longifurcate pharyngeate cercariae were observed and these cercariae were characterized morphologically and molecularly. Sequencing of ∼4,200 base pairs (bp) of the nuclear ribosomal genes and ∼450 bp of the mitochondrial cytochrome c oxidase gene revealed 3 genetically distinct species. One morphotype shared 99-100% sequence identity with metacercariae from the aqueous and vitreous humors of gizzard shad Dorosoma cepedianum and channel catfish Ictalurus punctatus as well as an adult trematode, Austrodiplostomum ostrowskiae, a parasite of the double-crested cormorant Nannopterum auritus. The remaining 2 cercariae morphotypes shared 99-100% sequence identity with an unidentified Tylodelphys sp. and Austrodiplostomum sp. metacercaria from the brain and eyes of several freshwater fish. Herein we molecularly link the cercaria, metacercaria, and adult stage of the life cycle of A. ostrowskiae, identifying the snail host for this parasite, in addition to providing notes

  10. Ciclo biológico de Paraibatrema inesperata n.g., n.sp. (Trematoda, Paramphistomidae, a partir de metacercárias desenvolvidas em Biomphalaria tenagophila (D'Orbigny, 1835 (Mollusca, Planorbidae

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    Marlene Tiduko Ueta

    1981-03-01

    Full Text Available Em exemplares de B. tenagophila, capturados em ambiente natural, foram encontradas paranfistomocercárias de precoce encistamento. Procedeu-se à infecção, per os, de animais de biotério; em camundongos e ratos, verificou-se o desenvolviemnto de trematóide paranfistomídeo desconhecido e que, por suas características, não se enquadra nos g~eneros conhecidos de Paramphistomidae de mamíferos. Para o parasito em apreço é proposta a denominação Paraibatema inesperata n.g, n.sp.. A partir de miracídios, oriundos de ovos eliminados pelos roedores em experiência, procurou-se infectar B. tenagophila e B. glabrata, criadas no moluscário. Verificou-se ser ativa a penetração dos miracídios no tecido do molusco, sendo freqüente a formação de tumorações nas antenas. A evolução experimental no hospedeiro intermediário apresenta-se lenta; ao fim de 40 dias de pós-infecção, não se observou a formação de esporocistos, rédias e cercárias.The new genus and new species of paramphistomid trematode, Paraibatrema inesperata n.g, n.sp., are proposed. The parasite was originally found as a quickly encysting paramphistome cercaria from specimens of the planorbid snail Biomphalaria tenagophila caught in natural habitats. Experimental infection resulted from intubation of metacercariae into the stomach of white mice and rats, which passed eggs in the feces 20 days later. Specimens of B. tenagophila and B. glabrata have been exposed to miracidia from eggs passed by mice. Penetration of the molluscan tegument was observed, but it seems that the larval development of the parasite is slow, inasmuch as no rediae and cercariae have been obtained as yet.

  11. A malacological survey in the Manso Power Plant, State of Mato Grosso, Brazil: new records of freshwater snails, including transmitters of schistosomiasis and exotic species

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    Monica Ammon Fernandez

    2014-07-01

    Full Text Available Introduction Schistosomiasis is a parasitic disease of public health concern in Brazil, and the construction of hydroelectric dams, in addition to increasing permanent human settlement and tourism, has created conditions suitable for the establishment of mollusks that can transmit schistosomiasis. Such areas require a number of actions to prevent the establishment of schistosomiasis. This paper reports on a freshwater malacological survey carried out in the geographical area of the Manso Power Plant. Methods Mollusks were collected in 18 municipalities in the State of Mato Grosso between February 2002 and February 2004 (qualitative study and from April 2009 to February 2011 (quantitative study. Results Thirty-one species of mollusks were collected, including newly recorded species (Antillorbis nordestensis and Burnupia ingae. In addition, the geographic distributions of known species, including Biomphalaria straminea, a snail vector of Schistosoma mansoni, were expanded. A total of 4,507 specimens were collected in the APM Manso reservoir (Usina Hidrelétrica de Aproveitamento Múltiplo de Manso during the quantitative study, and Biomphalaria amazonica was found in six of the 10 localities analyzed. The Afroasiatic species Melanoides tuberculata, introduced after February 2009, was the dominant species (relative abundance 94.96%. Conclusions The study area is epidemiologically important due to the occurrence of B. straminea and B. amazonica, which are vectors of schistosomiasis, and M. tuberculata, a snail host of Centrocestus formosanus, which is responsible for centrocestiasis transmission. Observations of M. tuberculata and the exotic freshwater clams Corbicula fluminea and Corbicula largillierti raise concerns about biodiversity.

  12. Freshwater gastropods of the Baixada Maranhense Microregion, an endemic area for schistosomiasis in the State of Maranhão, Brazil: I - qualitative study

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    Selma Patricia Diniz Cantanhede

    2014-01-01

    Full Text Available Introduction: The Baixada Maranhense Microregion currently has the highest prevalence of schistosomiasis in the State of Maranhão, likely because this parasitosis is characterized as an occupational disease, and increased contact with water increases the risk of infection by Schistosoma mansoni. This paper reports the results of the first comprehensive freshwater malacological survey performed in the Baixada Maranhense Microregion. Methods: Freshwater mollusks were collected from the twenty-one municipalities of the Baixada Maranhense Microregion and from Bacurituba and Cajapió and were evaluated for infection by trematodes. Results: A total of 9,129 mollusks were collected (sixteen species, which included the first records of six species in the State of Maranhão: Gundlachia radiata, G. ticaga, Hebetancylus moricandi, Plesiophysa guadeloupensis, Pomacea bridgesii diffusa and Omalonyx sp. Biomphalaria glabrata was found in five municipalities, whereas B. straminea was found in nine. Biomphalaria glabrata and B. straminea were observed in syntopy in Pinheiro and São Bento. Of the 990 specimens of B. glabrata and the 2,109 specimens of B. straminea that were exposed to and/or analyzed for the presence of larval trematodes, only a single specimen of B. glabrata (0.1% from São Bento shed S. mansoni. Other larval trematodes were first observed in mollusks from the State of Maranhão. Conclusions: These results indicate that the study area is epidemiologically important due to the presence of two natural vectors of schistosomiasis and the active transmission of schistosomiasis, which was confirmed in the infected specimen that was collected in this study.

  13. Structure and Function of the Digestive System of Solen Grandis Dunker

    Institute of Scientific and Technical Information of China (English)

    SHENG Xiuzhen; ZHAN Wenbin; REN Sulian

    2003-01-01

    Structure and function of the digestive system of a bivalve mollusc, Solen grandis, were studied using light microscopy and histochemical methods. The wall of digestive tube consists of four layers: the mucosal epithelium, connective tissue, muscular and fibrosa or serosa (only in the portion of rectum) from the inner to the outer. The ciliated columnar epithelial cells, dispersed by cup-shaped mucous cells, rest on a thin base membrane. There are abundant blood spaces in connective tissue layer. The digestive diverticula are composed of multi-branched duct and digestive tubules. The digestive tubules are lined with digestive and basophilic secretory cells, and surrounded by a layer of smooth muscle fibers and connective tissues. Activities of acid and alkaline phosphatases, esterase and lipase are detected in the digestive cells, and the epithelia of stomach and intestine, suggesting that these cells are capable of intracellular digesting of food materials and absorbing.Besides, acid phosphatase and esterase activities are present in the posterior portion of esophagus. Phagocytes are abundant in blood spaces and the lumens of stomach and intestine, containing brown granules derived from the engulfed food materials. The present work indicates that phagocytes play important roles in ingestion and digestion of food materials, which is supported as well by the activities of acid phosphatase, esterase and lipase detected in blood spaces.

  14. Population sampling of the golden mussel, Limnoperna fortunei (Dunker, 1857, based on artificial ceramic substrate

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    Paulo Eduardo Aydos Bergonci

    2009-09-01

    Full Text Available The ceramic substrate (21cm in length, 6cm in width and 1.3cm in depth was tested for the Limnoperna fortunei population, sampling at two localities in the Jacuí delta (Jacuí Canal (Canal do Jacuí – CJ and Port Docks (Cais do Porto – PO in Rio Grande do Sul state, Brazil. The individuals were quantified through the superimposition of a squared (1cm2 and segmented (sI, sII e sIII sheet on the substrate. Using Kruskal-Wallis and Mann-Whitnney, the recruit and adult average densities were compared in each segment, surface (smooth and pipe-shaped and sampling locality (α = 0.05. In CJ, the extreme and intermediate (adult segments differed statistically (p < 0.0001, as well as the ceramic substrate surfaces (recruits (p = 0.04. The recruit and adult densities between the CJ and PO localities also differed between themselves (p < 0.0001. The method was efficient for the invasive population sampling.

  15. The scientific literature on Limnoperna fortunei (Dunker 1857) from 1982 to 2012.

    Science.gov (United States)

    Barbosa, Fabiana G

    2014-09-01

    Limnoperna fortunei (golden mussel) is a freshwater bivalve native to Southeast Asia, but is becoming an invasive species in several aquatic ecosystems in the world. In this study, a scientometric analysis was performed to identify the patterns, trends and gaps of knowledge for this invasive species. A survey of the published literature was conducted using the database of the Thomson Institute for Scientific Information (ISI). A total of 107 papers were surveyed that were published between 1982 and 2012 in 60 journals. The number of papers on L. fortunei over the years has increased, especially within the last eight years of the study period. Argentina, Brazil, and Japan are the countries that contributed the most papers to the literature on invasive bivalve. The majority of papers were field-observational studies. Among some important gaps that need to be addressed are the relatively small number and/or lack of studies conducted in the native countries and in countries invaded by L. fortunei, the lack of internationally collaborative publications in these countries, as well as a low number of internationally collaborative studies.

  16. Dunker jäi Lätis pika ninaga / Piret Reiljan

    Index Scriptorium Estoniae

    Reiljan, Piret, 1983-

    2007-01-01

    Ilmunud ka: Delovõje Vedomosti 15. aug. lk. 9. Dunkri Kaubanduse AS pidi loobuma Läti importalkoholi hulgimüüja Lion ostmisest, kuna pooled ei jõudnud tehingu maksumuses kokkuleppele. Kommenteerib Alexander Bondarev. Tabel: Dunkri käive kasvas mullu üle 40%. Lisa: Lion. Vt. samas: Tehingu katkemine pidurdab laienemist

  17. Anthropogenic pollution stimulates oxidative stress in soft tissues of mussel Crenomytilus grayanus (Dunker1853)

    Science.gov (United States)

    Belcheva, Nina N.; Zakhartsev, Maxim V.; Dovzhenko, Nadezhda V.; Zhukovskaya, Avianna F.; Kavun, Victor Ya.; Chelomin, Victor P.

    2011-06-01

    The digestive gland and gills of the mussel Crenomytilus grayanus extracted from three locations — (i) sampled from a clean and (ii) polluted site and (iii) transplanted from the nonpolluted to polluted site - were analysed for antioxidant enzymes (superoxide dismutase, catalase, glutathione reductase), total oxyradical scavenging capacity and levels of lipid peroxidation products (malondialdehyde, conjugated dienes and lipofuscin). Perturbation of redox status was found in both digestive gland and gill tissues of mussels living in the polluted area. As the activities of superoxide dismutase and catalase were 1.2-3 times higher, the total oxyradical scavenging capacity was lower by 20-35% and the levels of lipid peroxidation products were 2-7 times higher compared to mussels from the reference site. In transplanted mussels, the lipid peroxidation process in both tissues was significantly stimulated (the level of conjugated dienes was increased 1.7-2.5-fold; malondialdehyde and lipofuscin contents were increased 3.5-5-fold) and the total oxyradical scavenging capacity fell by 50-70%. In addition, the transplantation generally resulted in transient and variable responses of antioxidant enzymes for both tissues. Complex response-behaviour of the antioxidant enzymes strongly points to the necessity of employing a combined approach that takes into account activities of antioxidant enzymes and the total oxyradical scavenging capacity, as well as measurement of oxidative damage (e.g., lipid peroxidation) to evaluate the physiological health of molluscs.

  18. Moluscos vectores da esquistossomose mansônica no lado leste do Rio São Francisco, no Estado da Bahia

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    Air Colombo Barretto

    1981-06-01

    Full Text Available Pela primeira vez foi realizado um levantamento malacológico de espécies vectoras de Schistosoma mansoni na região do lado Oeste do Rio São Francisco, no Estado da Bahia. Observou-se que nas áreas onde a única espécie encontrada foi B. straminea, a esquistossomose não constitui um problema médico. Entretanto, nas áreas onde foi coletado B. glabraata, além de B. straminea, a esquistossomose se apresenta com características de alta endemicidade. A ausência de moluscos, apesar da abundância de água, foi observada em extensas áreas, quase despovoadas. Esse quadro poderá se modificar em futuro bem próximo, devido â construção de novas estradas, bem como pela implantação de projetos de irrigação. Baseados nos presentes resultados e, em dados da literatura, os autores correlacionam a distribuição geográfica das espécies vectoras com a endemicidade da esquistossomose no Brasil.Snail vectors of Schistosomiasis mansoni west of the San Francisco River, State of Bahia, were surveyed for the first time. In areas where the only vector found was Biomphalaria straminea, Schistosomiasis does not appear to be a medical problem. However, in areas where B. glabrata was collected, in addition t B. straminea, schistosomiasis was highly endemic. In spite of an abundance of surface water, no sanils were found in sparsely populated areas. This could change as a result of proposed schemes of new roads and irrigation systems. The results presented here have been combined with previously data in order to demonstrate a correia tion between the geografic distribuition of different species of snail vectors and the endemicity of schistosomiasis mansoni throughout Brazil.

  19. Registro de ocorrência de vetores da esquistossomose mansônica em açude do Sertão de Pernambuco

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    Gazin Pierre

    2000-01-01

    Full Text Available O Sertão de Pernambuco não é área endêmica nem focal para esquistossomose mansônica. O presente trabalho registra a ocorrência de Biomphalaria straminea em açude da região, constatando que suas águas têm características físico-químicas favoráveis à proliferação destes moluscos. Chama a atenção para a possibilidade da introdução da doença no semi-árido, diante da crescente multiplicação de barragens.

  20. [Risk assessment and control measures for import of African schistosomiasis into China].

    Science.gov (United States)

    Liang, You-Sheng; Wang, Wei; Hong, Qing-Biao; Dai, Jian-Rong

    2013-06-01

    The habitats of Biomphalaria straminea, the intermediate host of Schistosoma mansoni, have been found in Hong Kong Special Administrative Region and Shenzhen City of People's Republic of China. Currently, there is a sharp increase in the number of Africa-aid projects and workers moving to Africa, and more and more cases infected with S. mansoni or S. haematobium returning from African countries have been detected in China. The possibility of transmission of African schistosomiasis in Chinese mainland, in the context of global climate warming, has received much attention. This paper illustrates the risk of transmission of African schistosomiasis in China based on biological and epidemiological features, and proposes interventions to tackle the risk.

  1. Invading freshwater snails and biological control in Martinique Island, French West Indies

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    Jean-Pierre Pointier

    2001-09-01

    Full Text Available Eight alien freshwater snail species were introduced into Martinique Island during the last 50 years. The introduced snails include four planorbids (Biomphalaria straminea, Helisoma duryi, Amerianna carinata and Gyraulus sp., three thiarids (Melanoides tuberculata, M. amabilis and Tarebia granifera and one ampullarid (Marisa cornuarietis. Four of these species rapidly colonized the whole Martinican hydrographic system whereas the other four remained restricted to some particular sites. The invasion processes were documented during the last 20 years and showed (i a rapid invasion of the island by several morphs of M. tuberculata at the beginning of the 80's; (ii the introduction of T. granifera in 1991 and M. amabilis in 1997; and (iii the rapid spread of these last two species throughout the island. In the years following its introduction, M. tuberculata was used in biological control experiments against the snail hosts of schistosomiasis, B. glabrata and B. straminea. Experiments were conducted with success in several groups of water-cress beds which constituted the latest transmission sites for schistosomiasis at the beginning of the 80's. A malacological survey carried out in 2000 all over the island showed the absence of B. glabrata but the presence of some residual populations of B. straminea. Long-term studies carried out in Martinique have shown that the thiarids are able to maintain relatively stable populations over a long period of time, thus preventing recolonization by the snail hosts. Within this context the invasion of the hydrographic system of Martinique by thiarid snails has resulted in an efficient and sustainable control of the intermediate hosts of schistosomiasis.

  2. Feeding behavior of the invasive bivalve Limnoperna fortunei (Dunker, 1857 under exposure to toxic cyanobacteria Microcystis aeruginosa

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    V Gazulha

    Full Text Available The aim of this study was to test the effects of cyanobacteria toxicity on feeding behavior of the golden mussel Limnoperna fortunei. First, it was tested the hypothesis that L. fortunei preferentially graze on non-toxic phytoplankton and reject toxic cyanobacteria. Second, it was tested the hypothesis that toxic cyanobacteria negatively affect feeding and survival of L. fortunei. The present study is the first to evaluate the effects of toxic cyanobacteria on L. fortunei feeding and survival. In the short-term grazing, golden mussel filtration rates were evaluated in the presence of toxic and non-toxic strains of cyanobacteria Microcystis aeruginosa, and non-toxic phytoplankton Nitzschia palea. Highest filtration rates were registered when mussels fed on Nitzschia. Despite that, golden mussel expelled Nitzschia cells in large quantities and preferentially ingested Microcystis cells, both toxic and non-toxic strains. In the long-term grazing, mussels were exposed to toxic and non-toxic strains of Microcystis during 5 days. Filtration rates were not significantly different for toxic and non-toxic Microcystis throughout exposure period. The results have demonstrated cyanobacteria toxicity is not the main factor influencing L. fortunei feeding behavior. Survival of L. fortunei feeding on toxic cyanobacteria shows the potential of this invasive bivalve as a vector to the transference of cyanotoxins to higher trophic levels.

  3. Estratégia competitiva entre Biomphalaria glabrata e Biomphalaria tenagophila: estudos de laboratório

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    Mairy Barbosa Loureiro dos Santos

    1989-01-01

    Full Text Available Observation about conhabitation among B. glabrata and B. tenagophila revealed a greater vulnerability of B. tenagophila population during the process of competition when its density was severaly decreased in 12 trials, moderate in 2 trials. It was higher than B. glabrata in only one trial. Some snail water chemical parameters analysed such as pH, alkalinity, conductivity and oxygen dissolve, an the viability rate of batch of eggs didn't give subsidy to explain the competition mechanism. The newly-born survival, in the situation of cohabitation, was low for both species. This reveals the existence of intra and interspecific competitive interacition. The fertility rate reduction of B. tenagophila during the cohabitation was considered as a cause of its exlusion. One of the factors that seems to have influenced the fertility rate was a possible wrong crossing.

  4. Estudos preliminares com bromoacetamida, um novo moluscicida

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    Naftale Katz

    1985-09-01

    Full Text Available A bromoacetamida tem sido testada como moluscicida na República Popular da China, para tratamento de criadouros de Oncomelania, hospedeiro do Schistosoma japonicum, com bons resultados. O produto é solúvel em água, o que simplifica seu uso. Foram feitos ensaios biológicos preliminares deste produto em caramujos adultos (Biomphalaria glabrata, B. tenagophila e B. straminea, recém-eclodidos e desovas. Paralelamente foram feitos ensaios com o pentaclorofenol para avaliar a suscetibilidade dos caramujos. O produto foi testado também sobre peixes, Lebistes reticulatus. Os moluscos testados mediam 8-10 mm de diâmetro; os recém-eclodidos tinham 1-3 dias de idade e as desovas 0-1 dia de idade. A temperatura da água durante os experimentos variou de 24,3 a 27,0°C. O produto foi ativo para caramujos adultos, recém-eclodidos e desovas, em concentrações em tomo de 1 a 4 ppm. Para os peixes o produto foi menos tóxico do que para os caramujos (CLço 7,5 ppm. Estes resultados indicam que a bromoacetamida apresenta propriedades moluscicidas promissoras para o controle da Biomphalaria spp.

  5. Potential schistosome-vector snails and associated trematodes in ricefields of Corrients province, Argentina: preliminary results

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    Alejandra Rumi

    1990-09-01

    Full Text Available Considering the possibility of introduction of schistosomiasis mansoni into Argentina as a consequence of dam construction on the Rio De La Plata basin, preliminary studies have been carried out on agrosystems such as ricefields in Corrientes province with the following purposes: 1 to survey and estimate the relative abundance of planorbids and identify potential vector species; 2 to identify environmental factors capable of influencing Biomphalaria population dynamics; and 3 to find out snail-parasite associations and estimate snail infection rates in order to detect possible competitive interactions between larval stages of native trematodes that could be used in biological control of Schistosoma mansoni. Three potential schistosome vectors were detected in ricefields, namely Biomphalaria straminea, B. tenagophila and B. peregrina, although B. orbignyi, a species refractory to infection with S. mansoni, proved the most frequent and abundant. Positive correlations (P0.05 was found in total iron, phosphates (SRP, pH and soil granulometry. Echinocercariae developed from rediae and belonging to Petasiger sp., Paryphostomum sp., and other undetermined species were found.

  6. RE-EVALUATION OF SCHISTOSOMIASIS MANSONI IN MINAS GERAIS, BRAZIL. III. "NOROESTE DE MINAS" MESOREGION

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    CARVALHO Omar S.

    1998-01-01

    Full Text Available This study was conducted to assess the presence of schistosomiasis mansoni in the "Noroeste de Minas" mesoregion, an area considered non-endemic. A malacologic survey and parasitologic stool examinations were undertaken in 13 municipalities of the mesoregion. A sample of 3,283 primary school students was submitted to fecal examination by the Kato-Katz method. A total of 3,627 planorbids was collected and examined. The molluscs were identified as Biomphalaria straminea in seven municipalities (Unaí, Bonfinópolis de Minas, Paracatu, João Pinheiro, Vazante, Lagamar and Lagoa Grande and as Biomphalaria peregrina in one (Presidente Olegário. All planorbids were negative for Schistosoma mansoni. Four students were diagnosed with schistosomiasis in the municipalities of Buritis, Formoso, Paracatu and Unaí, but none of these cases was considered autochthonous. The data obtained indicate that the "Noroeste de Minas" mesoregion continues to be non-endemic for schistosomiasis mansoni, although the presence of intermediate hosts associated with parasitized individuals emphasizes the need for epidemiological surveillance of schistosomiasis in this mesoregion.

  7. Estudos preliminares com bromoacetamida, um novo moluscicida

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    Naftale Katz

    1985-09-01

    Full Text Available A bromoacetamida tem sido testada como moluscicida na República Popular da China, para tratamento de criadouros de Oncomelania, hospedeiro do Schistosoma japonicum, com bons resultados. O produto é solúvel em água, o que simplifica seu uso. Foram feitos ensaios biológicos preliminares deste produto em caramujos adultos (Biomphalaria glabrata, B. tenagophila e B. straminea, recém-eclodidos e desovas. Paralelamente foram feitos ensaios com o pentaclorofenol para avaliar a suscetibilidade dos caramujos. O produto foi testado também sobre peixes, Lebistes reticulatus. Os moluscos testados mediam 8-10 mm de diâmetro; os recém-eclodidos tinham 1-3 dias de idade e as desovas 0-1 dia de idade. A temperatura da água durante os experimentos variou de 24,3 a 27,0°C. O produto foi ativo para caramujos adultos, recém-eclodidos e desovas, em concentrações em tomo de 1 a 4 ppm. Para os peixes o produto foi menos tóxico do que para os caramujos (CLço 7,5 ppm. Estes resultados indicam que a bromoacetamida apresenta propriedades moluscicidas promissoras para o controle da Biomphalaria spp.Bromocetamide has been tested as molluscicide, with good results, in the People's Republic of China, on Oncomelania, host of Schistosoma japonicum. We have conducted preliminary assays with bromoacetamide on adult snails (B. glabrata, B. tenagophila and B. straminea, newly hatched smails and egg-masses. This product has been also tested on fishes (Lebistes reticulatus. Comparative assays have been made with pentaclorophenol to evaluate the suceptibility of the snails. Snails tested had a diameter of 8-10 mm; the newly hatched were 1-3 days old and the eggs-masses. 0-1 day old. The temperature of the water varied from 24.3 to 27.5° C. Bromoacetamide was active on adult and newly hatched snails and egg-masses, in concentrations from 1-4ppm. The product was less toxic for jish (LC90 = 7,5 ppm. These results indicate that bromoacetamide has promising molluscicide

  8. A potential vector of Schistosoma mansoni in Uruguay Um vetor potencial do Schistosoma mansoni no Uruguai

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    W. Lobato Paraense

    1989-09-01

    Full Text Available Susceptibily experiments were carried out with a Biomphalaria straminea-like planorbid snail (Biomphalaria aff. straminea, species inquirenda from Espinillar, near Salto (Uruguay, in the area of the Salto Grande reservoir, exposed individually to 5 miracidia of Schistosoma mansoni (SJ2 and BH2 strains. Of 130 snails exposed to the SJ2 strain, originally infective to Biomphalaria tenagophila, 30 became infected (23%. The prepatent (precercaria period ranged from 35 to 65 days. The cercarial output was irregular, following no definite pattern, varying from 138 to 76,075 per snail (daily average 4.3 to 447.5 and ending up with death. Three specimens that died, without having shed cercarie, on days 69 (2 and 80 after exposure to miracidia, had developing secondary sporocysts in their tissues, justifying the prospect of a longer precercarial period in these cases. In a control group of 120 B. teangophila, exposed to the SJ2 strain, 40 became infected, showing an infection rate (33.3% not significantly different from that of the Espinillar snail (X [raised to the power of] 2 = 3.26. No cercarie were produced by any of the Espinilar snails exposed to miracidia of the BH2 strain, originally infective to Biomphalaria glabrata. Four specimens showed each a primary sporocyst in one tentacle, which disappeared between 15 and 25 days post-exposure, and two others died with immature, very slender sporocysts in their tissues on days 36 and 54. In a control group of 100 B. glabrata exposed to BH2 miracidia, 94 shed cercariae (94% and 6 remained negative. Calculation of Frandsen's (1979a, b TCP/100 index shows that "Espinillar Biomphalaria-SJ2 S. mansoni" is a vector-parasite "compatible" combination. Seeing that tenagophila-borne schistosomiasis is prevalent in Rio de Janeiro and São Paulo states and has recently spread sothwards to Santa Catarina state, and the range of B. tenagophila overlaps taht of the Espinillar Biomphalaria, the possibility of

  9. O uso da casca da castanha do caju, Anacardium occidentale, como moluscicida alternativo The use of cashew nut shell of caju (Anacardium occidentale as alternative molluscicide

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    Cecília Pereira de Souza

    1992-10-01

    Full Text Available Bioensaios usando extratos hexânicos de cascas da castanha do caju, Anacardium occidentale, coletadas no Ceará em 1972 (amostra 1 e em 1987 (amostra 2 foram feitos sobre moluscos adultos e desovas de Biomphalaria glabrata, B. tenagophila e B. straminea, no laboratório e no campo. As cascas, 18,5 g, sem triturar amostra 1, também foram testadas sobre moluscos adultos e desovas das três espécies. A toxidez do extrato foi testada ainda sobre peixes (Poecilia reticulata e girinos. As concentrações letais CL90, amostra 1, foram de 2,0 a 2,2 ppm para os moluscos das três espécies. Para B. glabrata adultos, recém-eclodidos e desovas as CL90, amostra 2, foram de 2,0, 0,5 e 30,0 ppm respectivamente. As cascas causaram mortalidade de 40 a 80% dos moluscos e de 22 a 35% dos embriões, ocasionando redução de 40 a 55% na oviposição das três espécies. O extrato hexânico, amostra 2, foi inócuo para girinos e peixes até 2 ppm. No campo, em poços com água parada, tratados com 20 ppm do extrato, amostra 1, ocorreu 97,1% de mortalidade de B. straminea e 100% de B. glabrata e B. tenagophila. Com a niclosamida a 3 ppm ocorreu 100% de mortalidade das três espécies.Bioassays using hexanolic extracts of cashew nut shells, of Anacardium occidentale, collected in Ceará in 1972 (Sample 1 and 1987 (Sample 2 were undertaken with adult snails and egg masses of Biomphalaria glabrata, B. tenagophila and B. straminea both in the laboratory and in the field. Non extracted shells, 18.5 g, sample 1, were also tested with adult snails and egg masses of the three species. The toxicity of extract was tested with fish (Poecilia reticulata and tadpoles. The lethal concentration, CL90, of sample 1 was from 2.0 to 2.2 ppm for adult snails of the three species. With sample 2, the CL90 was 2.0, 0.5 and 30.0 ppm for B. glabrata adults, newly hatched snails and egg mass respectively. Non extracted shells caused 40 - 80% mortality of adult snails, 22 - 35% mortality

  10. Levantamento malacológico em parques urbanos de Belo Horizonte, Minas Gerais, Brasil A malacological survey in city parks in Belo Horizonte, Minas Gerais, Brasil

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    Carlos Tito Guimarães

    1997-04-01

    Full Text Available Existem atualmente na região metropolitana de Belo Horizonte 18 parques urbanos (também denominados "parques ecológicos" com coleções hídricas (lagoas, nascentes, córregos etc. Pesquisas iniciais em 17 destes parques mostraram a ocorrência de moluscos hospedeiros intermediários do Schistosoma mansoni em pelo menos quatro deles. Capturas mensais nestes parques, de agosto/94 a fevereiro/96, mostraram os seguintes resultados em relação aos planorbíneos: Parque Julien Rien: 1.145 exemplares de Biomphalaria glabrata (2 mm a 13 mm; Parque Betânia: 149 exemplares de B. glabrata (4 mm a 13 mm; Parque Santa Lúcia: 2.431 exemplares de B. straminea (3 mm a 9 mm e Parque Lagoa do Nado: três exemplares de B. tenagophila (3 mm a 10 mm. As visitas aos parques terão prosseguimento e, após um diagnóstico sobre a situação de cada parque, serão sugeridas às autoridades municipais medidas de controle e/ou erradicação adequadas a cada área.The Greater Metropolitan Area of Belo Horizonte currently contains 18 city parks (also known as "ecological parks" with various bodies of water (lakes, springs, streams, etc. Initial research in 17 of these parks showed the occurrence of intermediate mollusk hosts for Schistosoma mansoni in at least 4. Monthly captures done from August 1994 to February 1996 showed the following results for these planorbids: Julien Rien Park: 1,145 specimens of Biomphalaria glabrata (2 to 13 mm; Betânia Park: 149 specimens of B. glabrata (4 to 13 mm; Santa Lúcia Park: 2,431 specimens of B. straminea (3 to 9 mm; and Lagoa do Nado Park: 3 specimens of B. tenagophila (3 to 10 mm. Visits to the parks will continue, and after a diagnosis of each park's situation, control and/or eradication measures suitable for each one will be proposed to the municipal authorities.

  11. Atual distribuição geográfica dos moluscos hospedeiros intermediários do Schistosoma mansoni em Belo Horizonte, MG, Brasil Current geographic distribution of intermediate hosts mollusca of Schistosoma mansoni in Belo Horizonte, MG, Brazil

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    Cecília Pereira de Souza

    1981-12-01

    Full Text Available Procedeu-se ao levantamento malacológico do município de Belo Horizonte, MG, com o objetivo de avaliar a distribuição, densidade e taxa de infecção dos moluscos hospedeiros intermediários do Schistosoma mansoni. Foram coletadas 3.261 Biomphalaria glabrata em 1979-81, das quais 100 (3,1% estavam infectadas com S. mansoni. Registrou-se a existência de 36 criadouros (35,0% de B. glabrata em 102 locais pesquisados, sendo 23 na bacia hidrográfica de Pampulha e 13 na do ribeirão do Arrudas. Foram encontrados 2 criadouros de B. tenagophila e 2 de B. straminea. Registrou-se também a presenca de exemplares de Pomacea haustrum, Physa sp e Drepanotrema cimex. Compararam-se os dados obtidos atualmente com os publicados em 1967. Houve reducao de mais de 50% no número de criadouros de B.glabrata, principalmente em decorrencias da expansão e progresso da cidade. Na zona periférica a esquistossomose continua endêmica, havendo necessidade de novas obras de saneamento básico para se conseguir o controle da doença.Malacological surveys were conducted in Belo Horizonte with a view to obtain new data on the distribution and density of schistosomose bearing snails and their natural rate of infection by Schistosoma mansoni. Of 3.261 Biomphalaria glabrata collected during 1979-81, 100 (3,1% were found naturally infected. One hundred and two water collections were surveyed and 36 (35% were found harboring the mentioned snail species (23 of them in the watershed of Pampulha, 13 in the tributaires of the Arrudas creek. The species B. tenagophila was found in two waterbodies, and B. straminea in two other. Other snail species collected were Pomacea haustrum, Physa sp and Drepanotrema cimex. Data of this survey were compared with data published in 1967 and 50% reduction in the snail breeding places was observed. This reduction was due mainly to public works and engineering activities accompanying the growth of city. Schistosomiasis is still present in the

  12. Four alien medical mollusk found in Dapeng Peninsula,Shenzhen City%深圳大鹏半岛4种入侵医学贝类的发现

    Institute of Scientific and Technical Information of China (English)

    曹世奎; 庄馨; 胡观冠

    2014-01-01

    Objective To investigate the alien snails in Dapeng Peninsula Shenzhen City. Methods The survey on the snail diversity in Dapeng Peninsula was carried out from August 2012 to Jan 2013 and the species of the alien snails were iden⁃tified according to the shell morphology. Results Four species of alien snails including Achatina fulica Pomacea canalicula⁃ta Physa acuta and Biomphalaria straminea were found in Dapeng Peninsula P. acuta was found in all of the collected sites A. fulica and P. canaliculata were distributed in five regions except Yangmeikeng area and B. straminea was just found in Dapeng Town. Conclusion Four species of important alien snails invade widely in Dapeng Peninsula Shenzhen City. As their potential risk to the disease transmission and agriculture production the relative departments should strengthen the control and prevention.%目的:了解深圳大鹏半岛入侵螺类物种。方法于2012年8月至2013年1月对深圳大鹏半岛进行软体动物资源调查,通过贝壳形态学观察等鉴定入侵螺种。结果大鹏半岛境内发现4种入侵螺类,均为医学贝类,分别为褐云玛瑙螺(Achatina fulica)、小管福寿螺(Pomacea canaliculata)、尖膀胱螺(Physa acuta)和藁杆双脐螺(Biomphalaria stra⁃minea)。其中尖膀胱螺在全部采集地点均有发现,褐云玛瑙螺和小管福寿螺在除杨梅坑外的调查点均有分布,藁杆双脐螺仅分布于大鹏镇。结论4种重要外来螺类在深圳大鹏半岛广泛入侵,鉴于其在疾病传播和农业生产上具有的潜在危害,需加强预防控制。

  13. Colonization of artificial substrate by golden mussel, Limnoperna fortunei (Dunker, 1857, in the Jacuí River Delta, Rio Grande do Sul State, Brazil.

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    Maria Cristina Dreher Mansur

    2009-03-01

    Full Text Available In order to test a colonization method for Limnoperna fortunei, experiments were carried out in the Jacuí River Delta (Rio Grande do Sul State, using wood substrate (X form. The sampling localities are in the Jacuí River Delta: Jacuí Canal (CJ and Port Docks (PO. In December (2005, three replicas of substrate were exposed at different depth levels (1; 1.5 and 2m in each sampling locality (total of 18 replicas. In March, all substrates were collected from the water and transported to the laboratory. The substrates were dehumidified in a Pasteur oven (60°C. The individual adults (> 0.5mm incrusted on different sides of the substrate (upperside, underside, lateral sides 1 and 2 were removed and quantified under a stereoscopic microscope. The average densities (ind.m-2 and standard errors of golden mussel adults were: CJ, 309.19 ± 30.70 and PO, 39.40 ± 6.00. The Kruskal-Wallis test (α = 0.05 did not present any significant differences between the depth levels (p = 0.715 or substrate sides (p = 0.617. However, the U Test presented differences (p < 0.0001 between sampling localities. The average densities of adult individuals verified in this study were situated between extreme values recorded earlier for wood substrate colonization, i. e. they were higher than those obtained for the Paraguay River and lower than those obtained for the Paraná River.

  14. Rural tourism as risk factor for the transmission of schistosomiasis in Minas Gerais, Brazil.

    Science.gov (United States)

    Enk, Martin J; Caldeira, Roberta L; Carvalho, Omar S; Schall, Virginia T

    2004-01-01

    Recently, the booming rural tourism in endemic areas of the state of Minas Gerais was identified as a contributing factor in the dissemination of the infection with Schistosoma mansoni. This article presents data from six holiday resorts in a rural district approximately 100 km distant from Belo Horizonte, MG, Brazil, where a possibly new and until now unperceived way of transmission was observed. The infection takes place in swimming pools and little ponds, which are offered to tourists and the local population for fishing and leisure activities. The health authorities of the district reported cases of schistosomiasis among the local population after visiting these sites. As individuals of the non-immune middle class parts of the society of big urban centers also frequent these resorts, infection of these persons cannot be excluded. A malacological survey revealed the presence of molluscs of the species Biomphalaria glabrata and Biomphalaria straminea at the resorts. The snails (B. glabrata) of one resort tested positive for S. mansoni. In order to resolve this complex problem a multidisciplinary approach including health education, sanitation measures, assistance to the local health services, and evolvement of the local political authorities, the local community, the tourism association, and the owners of the leisure resorts is necessary. This evidence emphasizes the urgent need for a participative strategic plan to develop the local tourism in an organized and well-administered way. Only so this important source of income for the region can be ensured on the long term without disseminating the disease and putting the health of the visitors at risk.

  15. Rural tourism as risk factor for the transmission of schistosomiasis in Minas Gerais, Brazil

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    Martin J Enk

    2004-08-01

    Full Text Available Recently, the booming rural tourism in endemic areas of the state of Minas Gerais was identified as a contributing factor in the dissemination of the infection with Schistosoma mansoni. This article presents data from six holiday resorts in a rural district approximately 100 km distant from Belo Horizonte, MG, Brazil, where a possibly new and until now unperceived way of transmission was observed. The infection takes place in swimming pools and little ponds, which are offered to tourists and the local population for fishing and leisure activities. The health authorities of the district reported cases of schistosomiasis among the local population after visiting these sites. As individuals of the non-immune middle class parts of the society of big urban centers also frequent these resorts, infection of these persons cannot be excluded. A malacological survey revealed the presence of molluscs of the species Biomphalaria glabrata and Biomphalaria straminea at the resorts. The snails (B. glabrata of one resort tested positive for S. mansoni. In order to resolve this complex problem a multidisciplinary approach including health education, sanitation measures, assistance to the local health services, and evolvement of the local political authorities, the local community, the tourism association, and the owners of the leisure resorts is necessary. This evidence emphasizes the urgent need for a participative strategic plan to develop the local tourism in an organized and well-administered way. Only so this important source of income for the region can be ensured on the long term without disseminating the disease and putting the health of the visitors at risk.

  16. Molecular investigation of Neorickettsia risticii in trematodes and snails in a region with serological evidence of this agent in horses, state of Rio de Janeiro

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    R.L. Costa

    Full Text Available ABSTRACT In Brazil, some studies have indicated that Neorickettsia risticii circulates in horses, but it is unclear which are the possible intermediate vectors of this bacterium in the country. The aim of this study was to use molecular techniques in order to analyze the presence of N. risticii in snails and larval stages of trematodes in farms in a region with a history of seroreactive horses towards this bacterium, in Rio de Janeiro, Brazil. Convenience sampling was used in the studied region. The collected snails were exposed to incandescent light (60W for 2-4 hours in order to investigate trematodes in larval forms. Deoxyribonucleic acid (DNA was extracted from snail tissue and trematode. Real-time PCR (qPCR technique was used to investigate the presence of a 16S rRNA gene fragment of N. risticii. Snail specimens (n=410 were collected from 11 horse-breeding farms, and the following species were identified: Melanoides tuberculata, Pomacea sp., Biomphalaria tenagophila, Physa acuta, Drepanotrema anatinum and Biomphalaria straminea. Only 3.17% (n=13/410 of the collected snails were infected by trematodes. The cercariae obtained from these snails were classified as Megalourous cercariae, Pleurolophocercus cercariae and Furcocercous cercariae. There was no amplification of the target DNA of N. risticii in the snail and trematode samples tested by qPCR. Based on these data, the transmission of N. risticii by trematodes using these snail species in this region does not appear to occur or occurs at very low rates. Thus, further studies are needed in order to clarify which species of invertebrate hosts are infected by this bacterium and potentially participate in the transmission chain of equine neorickettsiosis in the state of Rio de Janeiro, Brazil.

  17. Casos autoctones de esquistossomose mansonica em criancas de Recife, PE

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    Constanca Simoes Barbosa

    2013-08-01

    Full Text Available OBJETIVO : Investigar criadouros com moluscos hospedeiros e casos humanos autóctones para esquistossomose. MÉTODOS : Entre julho de 2010 e setembro de 2012 foram realizados: (1 levantamento malacológico para busca ativa de criadouros, coleta e identificação de caramujos Biomphalaria positivos para Schistosoma mansoni em Recife, PE; (2 inquérito de prevalência com 2.718 escolares, de sete a 14 anos, para diagnóstico de casos de esquistossomose; (3 exame clínico e ultrassonografia nos casos positivos para S. mansoni. Os casos foram investigados quanto à sua autoctonia e avaliados clinicamente. Os casos e criadouros foram georreferenciados e espacializados. RESULTADOS : Foram identificados 30 criadouros de B. straminea , quatro deles potenciais focos de transmissão, uma vez que os testes moleculares identificaram DNA de S. mansoni nos caramujos coletados. Foram diagnosticadas 14 crianças com esquistossomose; entre elas, cinco foram consideradas casos autóctones da doença. CONCLUSÕES : Ações emergenciais pela vigilância em saúde são necessárias para evitar que a esquistossomose se endemize em Recife, como acontece em localidades litorâneas do estado de Pernambuco.

  18. African schistosomiasis in mainland China: risk of transmission and countermeasures to tackle the risk.

    Science.gov (United States)

    Wang, Wei; Liang, You-Sheng; Hong, Qing-Biao; Dai, Jian-Rong

    2013-08-28

    Schistosomiasis is a major disease of public health importance in humans occurring in 76 countries of the tropics and sub-tropics. In China, schistosomiasis japonica is one of the highest priorities in communicable disease control defined by the central government. Since 1970s, the habitats of Biomphalaria straminea, an intermediate host of Schistosoma mansoni in South America, have been identified in Hong Kong Special Administrative Region and Shenzhen city, Guangdong province of China. With the sharp growth in the China-aided projects in Africa and labor services export to Africa, a gradual rise in the cases infected with S. haematobium or S. mansoni is reported in those returning from Africa to China. The existence of intermediate snail hosts and import of infectious source of schistosomiasis results in concern about the transmission of African schistosomiasis in mainland China in the context of global climate change. This paper evaluates the risk of transmission of African schistosomiasis in China, and proposes countermeasures and research priorities to tackle the risk.

  19. Levantamento malacológico em parques urbanos de Belo Horizonte, Minas Gerais, Brasil

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    Carlos Tito Guimarães

    1997-04-01

    Full Text Available Existem atualmente na região metropolitana de Belo Horizonte 18 parques urbanos (também denominados "parques ecológicos" com coleções hídricas (lagoas, nascentes, córregos etc. Pesquisas iniciais em 17 destes parques mostraram a ocorrência de moluscos hospedeiros intermediários do Schistosoma mansoni em pelo menos quatro deles. Capturas mensais nestes parques, de agosto/94 a fevereiro/96, mostraram os seguintes resultados em relação aos planorbíneos: Parque Julien Rien: 1.145 exemplares de Biomphalaria glabrata (2 mm a 13 mm; Parque Betânia: 149 exemplares de B. glabrata (4 mm a 13 mm; Parque Santa Lúcia: 2.431 exemplares de B. straminea (3 mm a 9 mm e Parque Lagoa do Nado: três exemplares de B. tenagophila (3 mm a 10 mm. As visitas aos parques terão prosseguimento e, após um diagnóstico sobre a situação de cada parque, serão sugeridas às autoridades municipais medidas de controle e/ou erradicação adequadas a cada área.

  20. Levantamento malacológico em parques urbanos de Belo Horizonte, Minas Gerais, Brasil

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    Guimarães Carlos Tito

    1997-01-01

    Full Text Available Existem atualmente na região metropolitana de Belo Horizonte 18 parques urbanos (também denominados "parques ecológicos" com coleções hídricas (lagoas, nascentes, córregos etc. Pesquisas iniciais em 17 destes parques mostraram a ocorrência de moluscos hospedeiros intermediários do Schistosoma mansoni em pelo menos quatro deles. Capturas mensais nestes parques, de agosto/94 a fevereiro/96, mostraram os seguintes resultados em relação aos planorbíneos: Parque Julien Rien: 1.145 exemplares de Biomphalaria glabrata (2 mm a 13 mm; Parque Betânia: 149 exemplares de B. glabrata (4 mm a 13 mm; Parque Santa Lúcia: 2.431 exemplares de B. straminea (3 mm a 9 mm e Parque Lagoa do Nado: três exemplares de B. tenagophila (3 mm a 10 mm. As visitas aos parques terão prosseguimento e, após um diagnóstico sobre a situação de cada parque, serão sugeridas às autoridades municipais medidas de controle e/ou erradicação adequadas a cada área.

  1. Schistosomiasis mansoni in Bananal (State of São Paulo, Brazil: II. Intermediate hosts

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    Horacio Manuel Santana Teles

    2002-10-01

    Full Text Available We conducted monthly snail captures in Bananal, State of São Paulo, Brazil, between March 1998 and February 2001, to identify Schistosoma mansoni vectors, estimate seasonal population changes, and delimit foci. We also evaluated the impact of improvements in city water supply and basic sanitation facilities. We identified 28,651 vector specimens, 28,438 as Biomphalaria tenagophila, 49 of them (0.2% infected with S. mansoni, and 213 as B. straminea, none of the latter infected. Vectors predominated in water bodies having some vegetation along their banks. Neither population density nor local vegetation could be linked to vector infection. We found the first infected snails in 1998 (from March to May. Further captures of infected snails ocurred, without exception, from July to December, when rainfall was least. Irrespective of season, overall temperature ranged from 16.5ºC to 21ºC; pH values, from 6.0 to 6.8. Neither factor was associated with snail population density. Frequent contact of people with the river result from wading across it, extracting sand from its bottom, fishing, washing animals, etc. Despite a marked reduction in contamination, cercaria shedding persists. Whatever the location along its urban course, contact with river Bananal, particularly of the unprotected skin, entails risks of infection.

  2. Mollusks (Gastropoda and Bivalvia) of the Multiple-Use Reserve Martín García Island, Río de la Plata River: biodiversity and ecology.

    Science.gov (United States)

    César, I I; Martín, S M; Rumi, A; Tassara, M

    2012-02-01

    The Island of Martin Garcia is located in the Upper Río de la Plata, to the south of mouth the Uruguay River. The aim of the present study was to analyse the biodiversity of the island freshwater mollusks and their relationships to environmental variables. Twelve sampling sites were selected, five were along the littoral section of the island and seven were Inland ponds. Seven major environmental variables were measured: water and air temperature, percentage of oxygen saturation, dissolved oxygen, electrical conductivity, total dissolved solids and pH. Twenty-seven mollusk species were found, Antillorbis nordestensis, Biomphalaria tenagophila tenagophila , B. t. guaibensis, B. straminea, B. peregrina, Drepanotrema kermatoides, D. cimex, D. depressissimum, Chilina fluminea, C. rushii, C. megastoma, Uncancylus concentricus, Hebetancylus moricandi, Stenophysa marmorata, Heleobia piscium, H. parchappii, Potamolithus agapetus, P. buschii, P. lapidum, Pomacea canaliculata, P. megastoma, Asolene platae, Corbicula fluminea, Eupera platensis, Pisidium sterkianum, P. taraguyense and Limnoperna fortunei. UPGMA clustering of species based on their occurrence in different ecological conditions revealed two main species groups. The Canonical Correspondence Analysis suggests that the species distribution is related to the physico-chemical condition of water. Axis two of the ordination diagram displayed the approximately 95.6% of the correlation between species and environmental variables. Dissolved oxygen, conductivity, water temperature and pH showed the highest fluctuations during the sampling period. The species richness (S) showed relationships mainly with water temperature and conductivity. The biodiversity of the gastropods and bivalves from Martín García Island amounts to up to 26 species. Among the Gastropoda, the Planorbidae family made the most sizeable contribution. The Lithogliphidae P. agapetus (26.28%) and P. buschii (9.50%) showed the highest relative

  3. Molluscicidal activity of crown of Christ (Euphorbia splendens var. hislopii (Euphorbiaceae latex submitted to pH variation

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    Vasconcellos Maurício Carvalho

    2003-01-01

    Full Text Available Laboratory and field bioassays have confirmed the specificity of the molluscicidal activity of the Euphorbia splendens var. hislopii latex (crown of Christ (Euphorbiaceae over snails of the species Biomphalaria glabrata, B. tenagophila, B. straminea, B. pfeifferi and Bulinus sp. in the control of Schistosoma mansoni. In the present study, the effect of the pH variation on lethal concentration (LC90 over B. tenagophila was evaluated. Bioassays with the aqueous solutions of the latex ranging from 0.4 to 12 µl/l were adjusted for pH of 5.0; 6.0; 7.0 and 8.0, and tested in accordance with methods standardized by World Health Organization. The results obtained indicated that the minor concentration of the latex occurred at pH 6.0 (LC90 = 3.2 µl/l and the maximum at pH 8.0 (LC90 = 10.3 µl/l. Lethal concentrations adjusted for pH 5.0 and 7.0 were 3.4 µl/l and 4,7µl/l, respectively. From the results it could be concluded that the molluscicidal toxicity was not altered when the concentrations were adjusted for pH 5.0 and 6.0, as we observed that mortality rate was 100% starting at a concentration of 2.0 µl/l, not the same for the concentrations with adjustment for pH 7.0 and 8.0.

  4. Risk assessment and control measures for import of African schistosomiasis into China%非洲输入性血吸虫病在中国的传播风险及其应对措施

    Institute of Scientific and Technical Information of China (English)

    梁幼生; 汪伟; 洪青标; 戴建荣

    2013-01-01

    中国香港和深圳地区相继出现曼氏血吸虫中间宿主—藁杆双脐螺孳生地;在我国援非项目和赴非务工人员数量剧增的同时,赴非洲回国人员中感染曼氏或埃及血吸虫的报道亦逐渐增多;在全球气候持续变暖的大环境下,非洲血吸虫病会否在中国境内传播或流行,再度引起了广泛关注.本文从生物学和流行病学角度,就其传播风险作一剖析,并提出相关应对措施.%The habitats of Biomphalaria straminea,the intermediate host of Schistosoma mansoni,have been found in Hong Kong Special Administrative Region and Shenzhen City of People' s Republic of China.Currently,there is a sharp increase in the number of Africa-aid projects and workers moving to Africa,and more and more cases infected with S.mansoni or S.haematobium returning from African countries have been detected in China.The possibility of transmission of African schistosomiasis in Chinese mainland,in the context of global climate warming,has received much attention.This paper illustrates the risk of transmission of African schistosomiasis in China based on biological and epidemiological features,and proposes interventions to tackle the risk.

  5. 海洋酸化对马氏珠母贝受精及早期发育的影响%Effect of ocean acidification on fertilization and early development of the pearl oyster Pinctada martensii Dunker

    Institute of Scientific and Technical Information of China (English)

    刘文广; 林坚士

    2012-01-01

    自2010年7月1日至3日,在pH值为8.1、7.7和7.4条件下研究了海洋酸化对马氏珠母贝(PinctadamartensiiDunker)受精及早期发育的影响。结果显示,海洋酸化对不同pH值下马氏珠母贝的受精率无显著影响。pH8.1、pH7.7和pH7.4试验纽幼虫的壳长、壳高的值逐渐增大,pH8.1组幼虫的壳长、壳高的值大于同期其他两组的值,且在实验的第24、36、48小时与其他两组同期幼虫的壳长、壳高的值差异显著,这表明海洋酸化显著影响马氏珠母91幼虫的生长。实验期间,pH8.1试验组幼虫的存活率和畸形率没有显著变化,而pH7.7和pH7.4组幼虫的存活率显著低于pH8.1组。pH7.4组幼虫的畸形率显著高于同期pH8.1和pH7.7组幼虫的畸形率,表明在海洋酸化的环境中幼虫的发育受到影响。本文将为海洋酸化的相关研究提供基础数据。%Effects of ocean acidification on fertilization and early development ofPinctada martensii were investi- gated at pH 8.1, 7.7 and 7.4 from July 1 to July 3 in 2010. The results indicated that COz-driven ocean acidification had no significant effect on fertilization. The shell lengths and heights in the groups ofpH 8.1, 7.7 and 7.4 increased gradually, and showed significant differences between the group of PH 8.1 and the other two groups. This indicated that ocean acidification influenced the growth of t3. martensii. During the experiment, the survival rate and the rate of abnormal larvae showed no significant difference in the pH 8.1 group. The survival rates in the pH 7.7 and 7.4 group were significantly lower than that in the pH 8.1 group. The rate of abnormal larvae in the pH 7.4 group was significantly higher than those in the other two groups. The development of the larvae was influenced by ocean acidification. The study provided basic information for exploring the effect of ocean acidification on growth and development of pearl oyster.

  6. Spatial variation of the length and humid weight of Limnoperna fortunei (Dunker, 1857 in Jacuí River Delta and Guaíba Lake Basin (Rio Grande do Sul State, Brazil

    Directory of Open Access Journals (Sweden)

    Paulo Eduardo Aydos Bergonci

    2008-12-01

    Full Text Available Natural clusters of golden mussels (Limnoperna fortunei were sampled in January 2005, in four stations of the Jacuí River Delta (Garças Creek (DAG and Jacuí Channel (DCJ and Guaiba Lake (Veludo beach (GPV and Pombas Pier (GPP, in Rio Grande do Sul State, Brazil. Measurements of the length and humid weight of 180 collected specimens were tested based on Kruskal-Wallis (α = 0.05 followed by the SNK test of significance for the different populations. This test did not show any significant differences between stations GPV and GPP for the length (p = 0.247 or humid weight (p = 0.912. However, differences were found between DAG and DCJ for these parameters, which also differed from those found for other stations (p < 0.001. Environmental characteristics (water current, food support, etc. and the effects of predation possibly have some influence on the differences among populations found in this study.

  7. Determinação do período de desenvolvimento e da viabilidade das desovas de duas populações de Biomphalaria glabrata e Biomphalaria tenagophila (Mollusca, Planorbidae

    Directory of Open Access Journals (Sweden)

    L. A. Magalhães

    1971-12-01

    Full Text Available Foram estudadas comparativamente as desovas ãe populações de B. glabrata e B. tenagophila, concluindo-se que nas condições da experiência, houve diferença significativa no que se refere ao período de desenvolvimento dos ovos. Foi verificada que a probabilidade de eclosão com relação ao número de dias de desenvolvimento dos ovos apresentou, em ambas as populações, uma distribuição de Poisson.

  8. Estudo do crescimento de moluscos pertencentes a populações de Biomphalaria glabrata e B. tenagophila

    Directory of Open Access Journals (Sweden)

    Luiz A. Magalhães

    1969-01-01

    Full Text Available Os autores estudam, comparativamente o crescimento de duas populações de moluscos planorbídeos pertencentes às espécies B. glabrata e B. tenagophila. Concluem que não há diferença significativa entre o crescimento dos caramujos oriundos das populações estudadas.

  9. Susceptibility of Biomphalaria alexandrina to the plant Azolla pinnata and some herbicides in relation to infection with Schistosoma mansoni miracidia.

    Science.gov (United States)

    Zidan, Z H; Hafez, A M; Abdel-Megeed, M I; el-Emam, M A; Ragab, F M; el-Deeb, F A

    1998-04-01

    Molluscicidal activity of the herebicides 2,4-D and Graminol, as well as both extracts and dry powder of the plant Azolla pinnata were evaluated against B. alexandrina snails. It was observed that 2,4-D proved to be the most toxic compound among he tested ones, showing LC90 of 52 ppm after 24 h of exposure. Ethanol extract of Azolla showed the highest molluscicidal activity against the tested snails compared with the other extracts and dry powder (LC90 = 3300 ppm). Ethanol extract at 6600 ppm after 3 h of exposure killed 100% and 19.4% of S. mansoni miracidia and cercariae, respectively. The molluscicidal activity of 2,4-D was not influenced by the presence of Azolla (900 plants/liter) for 7 days, while Graminol effect was significantly reduced. However, the infectivity of S. mansoni miracidia to B. alexandrina snails was not affected by Azolla existence.

  10. Influence de l'anhydrobiose sur l'infestation de Biomphalaria glabrata par un miracidium de Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Félix Lancastre

    1987-12-01

    Full Text Available Sur 410 B. glabrata infestées par 1 miracidium de S. mansoni, 300 ont été placées dans des boîtes aérées, sur de la terre humide, et soumises à 6 semaines de dessiccation progressive. Au terme de l'expérience, il y avait 71 survivantes (23.66%, dont 9 positives. Les 110 autres planorbes ont cosntitué le lot témein, avec 106 survivantes (96.36% à la première semaine d'apparition des cercaires. L'étude hebdomadaire des émissions cercariennes a montré des variations périodiques pour les deux sexes, une plus grande production de certaines femelles chez les témoins, mais une production de cercaires mâles ou femelles semblable chez les mollusques ayant subi l'anhydrobiose. Le faible nombre de ces dernies n'a pas permis une étude comparée significative de la survie des porteurs de formes larvaires mâles et femelles. La durée du développement du parasite chez son hôte ne semble pas modifiée si l'on tient compte de la phase d'estivation.

  11. Toxicity of lapachol and isolapachol and their potassium salts against Biomphalaria glabrata, Schistosoma mansoni cercariae, Artemia salina and Tilapia nilotica.

    Science.gov (United States)

    Lima, Nadja Maria Fernandes; dos Santos, Aldenir Feitosa; Porfírio, Zenaldo; Goulart, Marília O F; Sant'Ana, Antônio Euzébio G

    2002-07-01

    The toxicity of soluble derivatives (potassium salt) of lapachol and isolapachol in different stages of the life cycle of Schistosoma mansoni is evaluated. The potassium salts of isolapachol and lapachol showed significant molluscicidal activity against the adult snail (LC90Artemia salina Leach) indicated very high toxicity for the potassium salt of isolapachol (LC90=1.54 ppm), differently from the potassium salt of lapachol that can be considered non toxic (LC90=176.3 ppm). The same tendency is observed with piscicidal activity, for which the isolapachol salt has showed higher toxicity. The obtained selectivity ratios concerning LC50 and LC90 for lapachol, in relation to Tilapia nilotica lethality assay are 2.33 and 1.26, respectively. Despite the piscicidal toxicity, the use of the salt of lapachol can be recommended for field tests in Schistosomiasis, with caution.

  12. Effects of Enhanced UV-B Radiation on Antioxydative Enzymes in Gentiana straminea Leaves%增强UV-B辐射对麻花艽叶片的抗氧化酶的影响

    Institute of Scientific and Technical Information of China (English)

    李惠梅; 师生波

    2005-01-01

    以青藏高原的特有植物麻花艽为材料,研究麻花艽叶片抗氧化酶系统对增强UV-B辐射的响应.结果表明:在UV-B处理初期,麻花艽叶片SOD、POD的酶活性都能增加,但随着处理时间的延长,SOD、POD的活性呈现下降趋势.麻花艽叶片CAT的酶活性在UV-B处理后下降明显,但作为清除叶绿体中H2O2的关键酶AP的酶活性表现为明显地增加趋势,说明在对麻花艽叶片增强UV-B辐射反应中AP起有着重要作用.MDA的含量随UV-B处理时间延长而增加,表明UV-B降低了细胞内活性氧自由基的清除能力,膜脂过氧化作用加剧,导致了对麻花艽叶片的伤害效应.

  13. Environ: E00280 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available E00280 Gentiana macrophylla root (non-JP) Gentianae macrophyllae radix Large gentia...n root Crude drug Alkaloid, Gentianin [CPD:C06525], Gentianidine Gentiana macrophylla [TAX:50765], Gentiana ...straminea [TAX:50768], Gentiana crassicaulis [TAX:308434], Gentiana dahurica [TAX:225203] Same as: D10233 Gentianaceae (genti...an family) Gentiana macrophylla, Gentiana straminea, Gentiana crassicaulis, Genti

  14. [Latin American malacology. Freshwater mollusks from Argentina].

    Science.gov (United States)

    Rumi, Alejandra; Gregoric, Diego E Gutiérrez; Núñez, Verónica; Darrigran, Gustavo A

    2008-03-01

    . Species of sanitary interest are the propagators of: schistosomiasis -Biomphalaria peregrina, B. straminea y B. tenagophila, Planorbidae-, fasciolasis -Lymnaea viatrix and L. columnella, Lymnaeidae- and dermatitis -Chilina gibbosa and C. fluminea, Chilinidae. Invasive species are: Corbicula fluminea (Corbiculidae) and Limnoperna fortunei (Mytilidae). The construction of new areas for the protection and conservation of the high risk endemic species of freshwater molluscs is a priority. It is necessary to give special attention to the species of the patagonic mountain range and of the mesopotamic area of the Del Plata Basin.

  15. [Intestinal schistosomiasis in the freshwater mangrove of Guadalupe (French Antilles). Ecology of the vector, Biomphalaria glabrata and its parasite Schistosoma mansoni (author's transl)].

    Science.gov (United States)

    Pointier, J P; Theron, A

    1979-01-01

    In the freshwater mangrove of Dubelloy-Devarieux (Guadalupe), the dynamics of populations of B. glabrata and the transmission of S. mansoni, mostly depends on the alternation of dry and rainy season. The flooding of the mangrove (in september), permits a yearly renewal of the malacological populations. The sizes analysis of the snails shows that the life cycle of B. glabrata include two rainy seasons separated by one dry season. The prevalence of B. glabrata (0,25%) and cercariae densities (0,8 c/l) are very slow. The acrophase of the rhythm of presence in standing waters is reached at 2 pm. Men and rats are infected. The infections of rats is of 20% at the beginning of the rainy season and of 100% at the end of the rainy season. Principal factors involved in the infection of rats are discussed.

  16. Strukturelle Charakterisierung hämolymphproteingebundener N-Glykane und immunhistochemische Lokalisierung antigener Strukturen von Biomphalaria glabrata, die mit Glykokonjugaten des Humanparasiten Schistosoma mansoni kreuzreagieren

    OpenAIRE

    Lehr, Tobias

    2007-01-01

    In der vorliegenden Arbeit wurden N-Glykane der Zwischenwirtsschnecke Biomphala¬ria glabrata, die mit Glykokonjugaten des Humanparasiten Schistosoma mansoni serolo¬gisch kreuzreagieren, strukturell charakterisiert. Dazu waren die N-Glykane aus Hämolymphproteinen nicht-infizierter Schnecken nach proteolytischem Verdau enzyma¬tisch freigesetzt, durch Immunaffinitätschromatographie unter Verwendung von immobilisierten Antikörpern gegen lösliche Eiantigene von S. mansoni (anti-SEA) angereichert, ...

  17. Altered Gene Expression in the Schistosome-Transmitting Snail Biomphalaria glabrata following Exposure to Niclosamide, the Active Ingredient in the Widely Used Molluscicide Bayluscide

    OpenAIRE

    Si-Ming Zhang; Buddenborg, Sarah K.; Adema, Coen M.; John T Sullivan; Loker, Eric S

    2015-01-01

    In view of the call by the World Health Organization (WHO) for elimination of schistosomiasis as a public health problem by 2025, use of molluscicides in snail control to supplement chemotherapy-based control efforts is likely to increase in the coming years. The mechanisms of action of niclosamide, the active ingredient in the most widely used molluscicides, remain largely unknown. A better understanding of its toxicology at the molecular level will both improve our knowledge of snail biolog...

  18. Compatibilidad entre nueve cepas de Biomphalaria glabrata de áreas endémicas y no endémicas y una cepa de Schistosoma mansoni venezolanas

    Directory of Open Access Journals (Sweden)

    Pino Luz A.

    1999-01-01

    Full Text Available Se infectaron experimentalmente 9 lotes de 32 caracoles B. glabrata (de 5 a 7mm de diámetro con miracidios de la cepa C5 de Schistosoma mansoni a razón de 5 miracidios por caracol, pertenecientes a las siguientes cepas: En el área endémica de transmisión de Esquistosomiasis mansoni a Sector Puerta Negra, Lago Valencia, b Cagua c Ingenio Bolívar (Estado Aragua d Mariara e Caserío El 25 f Güigüe (Estado Carabobo. Fuera del área endémica de transmisión g Anzoátegui (Estado Lara, h Chabasquén (Estado Portuguesa, i Sector La Elvira, Caripe (Estado Monagas. El período prepatente intramolusco, osciló entre 23 y 25 días, para las 9 cepas evaluadas. La duración total de la infección fue muy variable desde 20 días para la cepa Chabasquén, hasta 93 días para la de Güigüe.La producción total promedio de cercarias al tercer día de iniciada la emisión varió desde X = 74,4 para la cepa de Mariara, hasta X = 591,7 para la cepa de Chabasquén. Se evidenció la existencia de diferencias estadísticamente significativas (H = 97,4, P < 0,05 en la producción total de cercarias al tercer día de iniciada la emisión, detectándose diferencias estadísticamente significativas para casi todas las 36 combinaciones, excepto para las cuatro siguientes: Mariara/Ingenio Bolívar, Cagua/Caserío El 25, Lago de Valencia/Güigüe y Güigüe/Caripe.En lo que respecta al porcentaje de caracoles que presentaron cura espontánea, los valores mas elevados se obtuvieron en las cepas del Lago de Valencia (88,8%, Cagua (85,2%, Chabasquén (82,6%, Caripe (82,6% y Anzoátegui (80%. Mientras que el porcentaje mas bajo se obtuvo para la cepa de Güigüe (21,4%.

  19. Florae Malesianae Precursores XXXII. Some new Cyperaceae

    NARCIS (Netherlands)

    Kern, J.H.

    1963-01-01

    Herba perennis, rhizomate lignoso, adscendente. Culmus erectus, radicibus crassis teretibus 2—3 mm diam. sustensus, dense foliatus, c. 50 cm altus. Folia linearia, rigida, opaca, glaucescentia, basin conduplicatam versus straminea, apice sensim in flagellum triquetrum scaberrimum angustata, usque ad

  20. Influência do magnésio metálico e diferentes sais de magnésio em desovas de Biomphalaria glabrata (Say, 1818 Influence of metallic magnesium and various magnesium salts on egg-masses of Biomphalaria glabrata (Say, 1818

    Directory of Open Access Journals (Sweden)

    Nelymar Martineli Mendes

    1983-12-01

    Full Text Available Soluções de magnésio metálico e diferentes sais de magnésio foram testadas em laboratório, a fim de comprovar a ação das mesmas sobre a oviposição de B. glabrata. Usaram-se, para cada solução, dez caramujos adultos originários da Pampulha, Belo Horizonte-MG (Brasil, criados em laboratório. No experimento I foram estudadas soluções em água desclorada de magnésio elementar (Mg, cloreto de magnésio (MgCl2.6H2O, carbonato de magnésio [(MgCO34.Mg(OH2.nH2O], nitrato de magnésio [Mg(NO32. 6H2O] e sulfato de magnésio (MgSO4.7H2O, e no experimento II, Mg, Mg + latossolo, MgCO3, MgCO3 + latossolo, sempre nas concentrações de 500 e 1.000 ppm. Durante duas semanas os planorbídeos permaneceram em água para adaptação; em seguida, por quatro semanas em exposição com as soluções testadas e, posteriormente, em água por mais duas semanas para recuperação. A cada sete dias as desovas eram contadas, eliminadas e as soluções renovadas. Foi observado que as soluções de Mg e MgCO3, isoladamente ou associada ao latossolo, produziram uma diminuição significativa do número de desovas dos caramujos, mas não parada completa de oviposição, quando comparados os períodos de adaptação com os de exposição. As soluções de Mg e MgCO3 não devem ser consideradas como produtos promissores para o controle da população de B. glabrata, em virtude da diminuição das desovas só terem sido observadas quando foram utilizadas concentrações muito altas.Solutions of magnesium metallic and other salts of magnesium were tested in the laboratory to study the action on B. glabrata oviposition. For each solution, 10 adult snails from Pampulha, Belo Horizonte-MG (Brazil, reared in the laboratory, were used. In experiment I solutions, in dechlorinated water, of magnesium (Mg, magnesium chloride (MgCl2. 6H2O, magnesium carbonate [(MgCO34.Mg(OH2.nH2O], magnesium nitrate [Mg(NO32.6H2O] and magnesium sulfate (MgSO4.7H2O were tested; and in experiment II, solutions of Mg, Mg + latosoil, MgCO3, MgCO3 + latosoil, always at concentrations of 500 and 1000 ppm. The snails were kept in dechlorinate water for an adaptation period of two weeks. Then, in the solutions tested, for an exposure period of four weeks, and then in dechlorinated water for a recuperation period of a further two weeks. Each seven days egg-masses were counted and eliminated and the solutions renewed. It was observed that the solutions of Mg and MgCO3 alone or in association with the latosoil were responsible for a significant decrease in the number of egg-masses, but not a complete stopping of oviposition, when adaptation and exposure periods were compared. The solutions of Mg and MgCO3 must not be considered as possible molluscicide for the control of B. glabrata populations, since the activity was detected only when a high concentration of those substances were used.

  1. Verificação de antagonismo entre larvas de Schistosoma mansoni e larvas de outros Digenea em Biomphalaria tenagophila, molusco planobídeo de criadouro natural situado na região de Campinas, SP, Brasil Verification of the antagonism between larvae of Schistosoma mansoni and those of other Digenea in Biomphalaria tenagophila, a planorbid molusc from a natural breeding ground in the region of Campinas, SP, Brazil

    Directory of Open Access Journals (Sweden)

    Soely Maria Pissini Machado

    1988-12-01

    Full Text Available Foi observado o comportamento de larvas de S. mansoni em moluscos prévia e naturalmente infectados por larvas de outros Digenea. Foi verificado que as larvas de S. mansoni não se desenvolveram nos moluscos previamente infectados com purcocercárias longifurcadas com ocelos ou com furcocercárias longifurcadas sem ocelos. Observou-se resistência parcial ao desenvolvimento de S. mansoni nos moluscos previamente infectados por equinostomocercárias ou por distomocercárias com acúleo. A ausência de reação amebocitária em torno dos esporocistos de S. mansoni nos moluscos infectados por outros digenéticos parece indicar a não participação dos amebócitos na resistência oferecida ao desenvolvimento das larvas de S. mansoni.The objective of the present work is to study the development of S. mansoni larvae in snails found naturally infected by other digenetic trematode larvae. It was found that S. mansoni larvae did not develop in snails previoulsy infected by furcicercariae either with or without ocelli. Partial resistance to the development of S. mansoni was observed in snails previously infected by cercariae of Echinostomatidae or by cercariae with aculeus of Distomata. Absence of amoebocitary reaction around the S. mansoni sporocysts in snails previously infected by other digenetic trematodes indicates that amoebocytes did not play any role in the resistance mechanism.

  2. Environmental Assessment for Type III Fuel Hydrant System at Grissom Air Reserve Base

    Science.gov (United States)

    2011-10-01

    Armoracia aquatica Aster furcatus Carex sparganioides var. cephaloidea Carex straminea Coeloglossum vir ide var. virescens Cypripedium calceolus var...American Badger Michaux’s Stitchwort Lake Cress forked Aster Thinleaf Sedge Straw Sedge Long-bract Green Orchis Small Yellow Ladys-slipper Tufted

  3. Flexible nets: disorder and induced fit in the associations of p53 and 14-3-3 with their partners

    OpenAIRE

    Uversky Vladimir N; Yang Mary Qu; Yang Jack Y; Meng Jingwei; Oldfield Christopher J; Dunker A Keith

    2008-01-01

    Abstract Background Proteins are involved in many interactions with other proteins leading to networks that regulate and control a wide variety of physiological processes. Some of these proteins, called hub proteins or hubs, bind to many different protein partners. Protein intrinsic disorder, via diversity arising from structural plasticity or flexibility, provide a means for hubs to associate with many partners (Dunker AK, Cortese MS, Romero P, Iakoucheva LM, Uversky VN: Flexible Nets: The r...

  4. Freshwater snails (Mollusca: Gastropoda) from the Commonwealth of Dominica with a discussion of their roles in the transmission of parasites

    Science.gov (United States)

    We collected six species of freshwater snails from Dominica, including Biomphalaria kuhniana, Gundlachia radiata Helisoma (= Planorbella) trivolvis, Melanoides tuberculata, Neritina punctulata, and Physa marmorata. Our collections indicate that un-reported species such as Gundlachia radiata and Hel...

  5. Molluscicidal saponins from a Zimbabwean strain of Phytolacca dodecandra

    DEFF Research Database (Denmark)

    Thiilborg, S. T.; Christensen, S. B.; Cornett, Claus

    1994-01-01

    -hydroxyoleanolic acid. Two of the saponins were submitted to a preliminary screening for molluscicidal activity against the schistosomiasis transmitting snail Biomphalaria glabrata and showed, respectively, strong and weak activity. In addition, four saponins previously reported from other strains of Phytolacca...

  6. Estudo dos dados obtidos de uma população de Biomphalaria glabrata de Belo Horizonte infectada por schistosoma mansoni da mesma cidade, e de uma população de B. tenagophila de Campinas. infectada por S. mansoni de São José dos Campos

    Directory of Open Access Journals (Sweden)

    Luiz A. Magalhães

    1969-01-01

    Full Text Available O autor estuda os dados obtidos pela infecção de moluscos de Campinas e de Belo Horizonte por miracídios de S. mansoni. Chega à conclusão de que a população de Belo Horizonte mostrou-se mais susceptível à infecção pelo helminto do que a população de moluscos Campinas.

  7. Molluscicidal effect of suspension concentrate of niclosamide against Biomphalaria glabrata, an intermediate host of Schistosoma mansoni%氯硝柳胺悬浮剂杀灭曼氏血吸虫中间宿主光滑双脐螺效果观察

    Institute of Scientific and Technical Information of China (English)

    戴建荣; 汪伟; 李洪军; 陶永辉; Gerald C Coles; 梁幼生

    2009-01-01

    目的 观察氯硝柳胺悬浮剂(SCN)对光滑双脐螺的杀灭效果.方法 用SCN、50%氯硝柳胺乙醇胺盐可湿性粉剂(WPN)和氯硝柳胺原药分别配制成药物有效浓度为1.000、0.500、0.250、0.125 mg/L和0.063 mg/L的溶液,在实验室浸泡光滑双脐螺成螺,计算LC50.采用上述3种剂型的氯硝柳胺分别配制成药物有效浓度为0.500、0.250、0.125、0.063mg/L和0.032 mg/L的溶液,浸泡螺卵,计算LC50.结果 将成螺浸泡在SCN、WPN和氯硝柳胺溶液中,24 h LC50分别为0.218、0.218 mg/L和0.203 mg/L;48 h LC50分别为0.189、0.203 mg/L和0.189 me,/L;72 h LC50分别为0.165、0.218 mg/L和0.177 mg/L.将螺卵浸泡在SCN、WPN和氯硝柳胺溶液中,24 h LC50分别为0.153、0.173 mg/L和0.171 mg/L;48 hLC50分别为0.085、0.096 mg/L和0.155 mg/L;72 h LC50分别为0.077、0.097 mg/L和0.087 mg/L.结论 SCN对光滑双脐螺成螺和螺卵均具有与WPN和原药相同的杀灭效果.

  8. A Benzoic Acid Derivative and Flavokawains from Piper species as Schistosomiasis Vector Controls

    Directory of Open Access Journals (Sweden)

    Ludmila N. Rapado

    2014-04-01

    Full Text Available The search of alternative compounds to control tropical diseases such as schistosomiasis has pointed to secondary metabolites derived from natural sources. Piper species are candidates in strategies to control the transmission of schistosomiasis due to their production of molluscicidal compounds. A new benzoic acid derivative and three flavokawains from Piper diospyrifolium, P. cumanense and P. gaudichaudianum displayed significant activities against Biomphalaria glabrata snails. Additionally, “in silico” studies were performed using docking assays and Molecular Interaction Fields to evaluate the physical-chemical differences among the compounds in order to characterize the observed activities of the test compounds against Biomphalaria glabrata snails.

  9. Phytochemical study and evaluation of the molluscicidal activity of Calophyllum brasiliense Camb (Clusiaceae); Estudo fitoquimico e avaliacao da atividade moluscicida do Calophyllum brasiliense Camb (Clusiaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Gasparotto Junior, Arquimedes; Brenzan, Mislaine Adriana; Piloto, Izabel Cristina; Cortez, Diogenes Aparicio Garcia [Universidade Estadual de Maringa, PR (Brazil). Dept. de Farmacia e Farmacologia]. E-mail: dagcortez@uem.br; Nakamura, Celso Vataru; Dias Filho, Benedito Prado [Universidade Estadual de Maringa, PR (Brazil). Dept. de Analises Clinicas; Rodrigues Filho, Edson; Ferreira, Antonio Gilberto [Sao Carlos Univ., SP (Brazil). Dept. de Quimica

    2005-07-15

    The bioassay-guided fractionation against Biomphalaria glabrata of hydroalcoholic extracts of Calophyllum brasiliense aerial parts led to the isolation of the coumarin, named (-) mammea A/BB. The compound had its structure determined by both spectroscopic techniques (NMR {sup 1}H, NMR {sup 13}C, gHSQC, gHMBC and MS) and some literature comparison data. The probit analysis of (-) mammea A/BB showed LD{sub 50} = 0.67 ppm and LD{sub 90} = 1.47 ppm. In addition, the dichloromethane extract obtained from C. brasiliense leaves with significant molluscicidal activity against Biomphalaria glabrata was analyzed by HPLC-UV. (author)

  10. Estudo fitoquímico e avaliação da atividade moluscicida do Calophyllum brasiliense Camb (Clusiaceae Phytochemical study and evaluation of the molluscicidal activity of Calophyllum brasiliense Camb (Clusiaceae

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    Arquimedes Gasparotto Jr.

    2005-08-01

    Full Text Available The bioassay-guided fractionation against Biomphalaria glabrata of hydroalcoholic extracts of Calophyllum brasiliense aerial parts led to the isolation of the coumarin, named (- mammea A/BB. The compound had its structure determined by both spectroscopic techniques (NMR ¹H, NMR 13C, gHSQC, gHMBC and MS and some literature comparison data. The probit analysis of (- mammea A/BB showed LD50 = 0.67 ppm and LD90 = 1.47 ppm. In addition, the dichloromethane extract obtained from C. brasiliense leaves with significant molluscicidal activity against Biomphalaria glabrata was analyzed by HPLC-UV.

  11. Modeling the distribution of Schistosoma mansoni and host snails in Uganda using satellite sensor data and Geographical Information Systems

    DEFF Research Database (Denmark)

    Stensgaard, Anna-Sofie; Jørgensen, A; Kabatereine, N B

    2005-01-01

    The potential value of MODIS satellite sensor data on Normalized Difference Vegetation Index (NDVI) and land surface temperatures (LST) for describing the distribution of the Schistosoma mansoni-"Biomphalaria pfeifferi"/Biomphalaria sudanica parasite-snail system in inland Uganda, were tested....... The parasite, however, appears to be restricted in its distribution in both the north-eastern and the south-western regions of Uganda. The absence of disease in the south-west can not be attributed to the absence of snail hosts. Results suggest a combination of satellite sensor data on temperature and standard...

  12. A benzoic acid derivative and flavokawains from Piper species as schistosomiasis vector controls.

    Science.gov (United States)

    Rapado, Ludmila N; Freitas, Giovana C; Polpo, Adriano; Rojas-Cardozo, Maritza; Rincón, Javier V; Scotti, Marcus T; Kato, Massuo J; Nakano, Eliana; Yamaguchi, Lydia F

    2014-04-23

    The search of alternative compounds to control tropical diseases such as schistosomiasis has pointed to secondary metabolites derived from natural sources. Piper species are candidates in strategies to control the transmission of schistosomiasis due to their production of molluscicidal compounds. A new benzoic acid derivative and three flavokawains from Piper diospyrifolium, P. cumanense and P. gaudichaudianum displayed significant activities against Biomphalaria glabrata snails. Additionally, "in silico" studies were performed using docking assays and Molecular Interaction Fields to evaluate the physical-chemical differences among the compounds in order to characterize the observed activities of the test compounds against Biomphalaria glabrata snails.

  13. Contribuição ao levantamento da carta planorbídica do Estado de São Paulo: Pesquisa de focos com formas evolutivas do Schistosoma mansoni. II. Município de Peruibe (Litoral Sul do Estado de São Paulo Contribution to the survey of the planorbid chart of the State of São Paulo (Brazil: Investigation of foci with evolutive forms of Schistosoma mansoni. II. Peruibe county (Southern coast of the State of São Paulo

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    Mário Demar Perez

    1969-12-01

    Full Text Available Em levantamento realizado em Peruibe, em janeiro de 1966, foram identificados focos de Biomphalaria tenagophila infestados com formas evolutivas do Schistosoma mansoni.In this work the occurence of Biomphalaria tenagophila naturally parasited by evolutive forms of Schistosoma mansoni is registered in the city of Peruibe, situated in the Southern Littoral of the State of São Paulo (Brazil. Besides B. tenagophila, in the region it occurs also Drepanotrema cimex, a species not proved to be a host of Schistosoma mansoni and whose occurence had not yet been recorded in Peruibe.

  14. Diagnóstico da esquistossomose mansônica mediante técnica de imunofluorescência com esporocistos em tecidos de planorbídeos Diagnosis of mansoni schistosomiasis by means of immunofluorescent technique using sporocysts in planorbid tissues

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    Ana Maria Aparecida Guaraldo

    1981-12-01

    Full Text Available Propõe-se uma técnica de imunofluorescência para diagnóstico da esquistossomose mansônica, adotando-se tecidos de Biomphalaria glabrata contendo esporocistos secundários de Schistosoma mansoni. A reação de imunofluorescência indireta é executada sobre cortes histológicos preparados por inclusão em parafina.An immunofluorescent technique is proposed for diagnosis of mansoni schistosomiasis using Biomphalaria glabrata tissue with secondary sporocysts. The indirect immunofluorescent reaction is carried out on histological sections prepared by embedding in paraffin.

  15. The molluscicidal activity of coumarins from Ethulia conyzoides and of dicumarol

    DEFF Research Database (Denmark)

    Kady, M M; Brimer, L; Furu, P

    1992-01-01

    The molluscicidal principles of Ethulia conyzoides were identified as ethuliacoumarin A (1) and isoethuliacoumarin A (2). Ethuliacoumarin A possessed an LC90 between 19 and 23.5 ppm depending on the age of the snail against Biomphalaria glabrata, and between 12 and 15 ppm against Bulinus truncatu...

  16. Genetic variability and identification of the intermediate snail hosts of Schistosoma mansoni

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    Teofânia HDA Vidigal

    1998-01-01

    Full Text Available Studies based on shell or reproductive organ morphology and genetic considerations suggest extensive intraspecific variation in Biomphalaria snails. The high variability at the morphological and genetic levels, as well as the small size of some specimens and similarities between species complicate the correct identification of these snails. Here we review our work using methods based on polymerase chain reaction (PCR amplification for analysis of genetic variation and identification of Biomphalaria snails from Brazil, Argentina, Uruguay and Paraguay. Arbitrarily primed-PCR revealed that the genome of B. glabrata exihibits a remarkable degree of intraespecific polymorphism. Low stringency-PCR using primers for 18S rRNA permited the identification of B. glabrata, B. tenagophila and B. occidentalis. The study of individuals obtained from geographically distinct populations exhibits significant intraspecific DNA polymorphism, however specimens from the same species, exhibit some species specific LSPs. We also showed that PCR-restriction fragment of length polymorphism of the internal transcribed spacer region of Biomphalaria rDNA, using DdeI permits the differentiation of the three intermediate hosts of Schistosoma mansoni. The molecular biological techniques used in our studies are very useful for the generation of new knowledge concerning the systematics and population genetics of Biomphalaria snails.

  17. Diagnosing Medical Parasites: A Public Health Officers Guide to Assisting Laboratory and Medical Officers

    Science.gov (United States)

    2009-01-01

    and rediae develop, or penetrate and encyst in other animals such as amphibians or fish. (SOURCE: PHIL 3393 - CDC/Alexander J. da Silva, PhD...Arabian Peninsula, Brazil, Surinam , Venezuela and the West Indies. The intermediate host is an aquatic snail of the genus Biomphalaria. Man is the

  18. A faunistic study on the leafhoppers of northwestern Iran (Hemiptera, Cicadellidae

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    Tandis Abdollahi

    2015-04-01

    Full Text Available The leafhopper fauna of northwestern Iran: Azarbaijan-e-Sharghi, Azarbaijan-e-Gharbi and Ardabil provinces is listed from previously published records and from our current work. Sixty-nine species are included with four species (Mogangella straminea Dlabola, 1957, Doratura stylata (Boheman, 1847, Macrosteles sordidipennis (Stål, 1858 and Psammotettix seriphidii Emeljanov, 1962 listed as new for Iran and Balclutha punctata (Fabricius, 1775, as a new record for the region. A distribution map of the species in northwestern Iran is given.

  19. Moluscos vectores da esquistossomose mansônica no lado leste do Rio São Francisco, no Estado da Bahia

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    Air Colombo Barretto

    1981-06-01

    Full Text Available Pela primeira vez foi realizado um levantamento malacológico de espécies vectoras de Schistosoma mansoni na região do lado Oeste do Rio São Francisco, no Estado da Bahia. Observou-se que nas áreas onde a única espécie encontrada foi B. straminea, a esquistossomose não constitui um problema médico. Entretanto, nas áreas onde foi coletado B. glabraata, além de B. straminea, a esquistossomose se apresenta com características de alta endemicidade. A ausência de moluscos, apesar da abundância de água, foi observada em extensas áreas, quase despovoadas. Esse quadro poderá se modificar em futuro bem próximo, devido â construção de novas estradas, bem como pela implantação de projetos de irrigação. Baseados nos presentes resultados e, em dados da literatura, os autores correlacionam a distribuição geográfica das espécies vectoras com a endemicidade da esquistossomose no Brasil.

  20. Problemas para la elaboración y tipificación de tests en distintos ambientes culturales

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    Nuria Cortada de Kohan

    1972-01-01

    Full Text Available This paper points out the difficulties of translating and standardizing several tests of verbal and general ability, specific aptitudes and personality inventories. The problems are mainly Iinguistic. They indude difficulties in correct translation and varying frequency of use in the different languages. A number of examples are given of responses to items by normals and psychiatric patients in Argentina. Because of the many problems involved, the suggestion is made that serious considerations be given to the construction of a new type of instrument. References are made to the work of Dunker, Bloom, Píaget and Rimoldi ho emphasize the study of processes rather than produces. The methodology presented by Rimoldi appears to be more devoid of cultural biases and should have greater usefulness in cross cultural studies.

  1. Climatic Signals in the Last 200 Years from Stable Isotope Record in the Shells of Freshwater Snails in Lake Xingcuo,Eastern Tibet Plateau,China

    Institute of Scientific and Technical Information of China (English)

    吴敬禄; A.LUECKE; 等

    2002-01-01

    Lake Xingcuo is a small closed,hard-water lake ,situated on eastern Tibet Plateau.Stable isotope data(δ18O and δ13C) from the freshwater snail Gyraulus sibirica(Dunker)in a34 cm long,radioactive isotope-dated sediment core represent the last 200 years of Lake Xingcuo environmental history.Carbon and oxygen isotope ratios in the shells of the freshwater snail bear information on the isotopic composition of the water in which the shells were formed ,which in turn characterizes the climatic conditions prevailing during the snail's life span.Whole-shell and incremental growth data were collected from modern and fossil shells from Lake Xingcuo.The δ18O values of modern shells from Lake Xingcuo are in equilibrium with high δ13CTDIC.By calibrating δ18O and δ13C in the shell Gyraulus sibirica(Dunker)with in-strument-measured data for the period 1954-1992,we found that the δ18O of the snail shells is an efficient indicator to reveal air temperature in the warmer half year instead of that around the whole year,and that there is a certain positive correlation between index δ18O and the run-ning average temperature in the warmer half-yiar period.Climatic variability on eastern Tibet Plateau,for the last two centuries,has been successfully inferred from the δ18O record in freshwater snails in the sediments of Lake Xingcuo.As such,the last 200 years of palaeocli-matic record for this region can be separated into three periods representing oscillations between warming and cooling,which are confirmed by the Guliya ice record on the Tibet Plateau.

  2. Climatic Signals in the Last 200 Years from Stable Isotope Record in the Shells of Freshwater Snails in Lake Xingcuo, Eastern Tibet Plateau, China

    Institute of Scientific and Technical Information of China (English)

    WU JINGLU(吴敬禄); LI SHIJIE(李世杰); A.LUECKE; WANG SUMIN(王苏民)

    2002-01-01

    Lake Xingcuo is a small closed, hard-water lake, situated on eastern Tibet Plateau.Stable isotope data (δ 18O and δ 13C) from the freshwater snail Gyraulus sibirica (Dunker) in a 34 cm long, radioactive isotope-dated sediment core represent the last 200 years of Lake Xingcuo environmental history. Carbon and oxygen isotope ratios in the shells of the freshwater snail bear information on the isotopic composition of the water in which the shells were formed,which in turn characterizes the climatic conditions prevailing during the snail's life span.Whole-shell and incremental growth data were collected from modern and fossil shells from Lake Xingcuo. The δ 18O values of modern shells from Lake Xingcuo are in equilibrium with those of modern waters, while δ 13C values are indicative of snail dietary carbon and a lake with high δ 13CTDIC. By calibrating δ 18O and δ 13C in the shell Gyraulus sibirica (Dunker) with in strument-measured data for the period 1954 - 1992, we found that the δ 18O of the snail shells is an efficient indicator to reveal air temperature in the warmer half year instead of that around the whole year, and that there is a certain positive correlation between index δ 18O and the running average temperature in the warmer half-year period. Climatic variability on eastern Tibet Plateau, for the last two centuries, has been successfully inferred from the δ 18O record in freshwater snails in the sediments of Lake Xingcuo. As such, the last 200 years of palaeoclimatic record for this region can be separated into three periods representing oscillations between warming and cooling, which are confirmed by the Guliya ice record on the Tibet Plateau.

  3. Use of indicator kriging to investigate schistosomiasis in minas gerais state, Brazil.

    Science.gov (United States)

    Guimarães, Ricardo J P S; Freitas, Corina C; Dutra, Luciano V; Felgueiras, Carlos A; Drummond, Sandra C; Tibiriçá, Sandra H C; Oliveira, Guilherme; Carvalho, Omar S

    2012-01-01

    Geographic Information Systems (GISs) are composed of useful tools to map and to model the spatial distribution of events that have geographic importance as schistosomiasis. This paper is a review of the use the indicator kriging, implemented on the Georeferenced Information Processing System (SPRING) to make inferences about the prevalence of schistosomiasis and the presence of the species of Biomphalaria, intermediate hosts of Schistosoma mansoni, in areas without this information, in the Minas Gerais State, Brazil. The results were two maps. The first one was a map of Biomphalaria species, and the second was a new map of estimated prevalence of schistosomiasis. The obtained results showed that the indicator kriging can be used to better allocate resources for study and control of schistosomiasis in areas with transmission or the possibility of disease transmission.

  4. Use of Indicator Kriging to Investigate Schistosomiasis in Minas Gerais State, Brazil

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    Ricardo J. P. S. Guimarães

    2012-01-01

    Full Text Available Geographic Information Systems (GISs are composed of useful tools to map and to model the spatial distribution of events that have geographic importance as schistosomiasis. This paper is a review of the use the indicator kriging, implemented on the Georeferenced Information Processing System (SPRING to make inferences about the prevalence of schistosomiasis and the presence of the species of Biomphalaria, intermediate hosts of Schistosoma mansoni, in areas without this information, in the Minas Gerais State, Brazil. The results were two maps. The first one was a map of Biomphalaria species, and the second was a new map of estimated prevalence of schistosomiasis. The obtained results showed that the indicator kriging can be used to better allocate resources for study and control of schistosomiasis in areas with transmission or the possibility of disease transmission.

  5. Molluscicidal properties of some species of Annona.

    Science.gov (United States)

    dos Santos, A F; Sant'Ana, A E

    2001-03-01

    In search for plant molluscicides for the vector control of schistosomiasis, ethanolic extracts from different parts of six species of the Annonaceae family were evaluated against adult forms and egg masses of Biomphalaria glabrata. Results from accurate experiments indicate that the majority of analyzed extracts possess properties lethal to Biomphalaria glabrata, some of them with significant LD90 values (Annona crassiflora M: [pulp and seed (LD50 = 13.21), steem (2.34), root bark (3.79)], Annona glabra L. [seed (17.02)], Annona muricata [leaf (8.75)]. Emphasis is held mainly into Annona muricata L. (leaf) and Annona squamosa Veil. (root) for presenting additional toxicity toward snail egg masses.

  6. Population dynamics of aquatic snails in Pampulha reservoir

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    J. R. Freitas

    1987-01-01

    Full Text Available An attempt was made to determine more accurately the density of molluskan populations in the Pampulha reservoir, using the quadrate method, intending to detect the fluctuation of the populations density, the habitat conditions and the possible competitive interactions among Biomphalaria tenagophila, Melanoides tuberculata, Pomacea haustrum and Biomphalaria glabrata, through the analysis of populational parameters. Among the most significative facts observed in the reservoir it has to be mentioned: the almost disappearance of B. glabrata; the invasion, colonization, fixation and fast growing of M. tuberculata population until reaching about 11,000 individuals/[square metre]; the density fluctuations of B. tenagophila, P. haustrum and M. tuberculata alives and deads; differences on the habitat preference of these three molluskan species at the edge (at the limit earth-water, at 0.70m and 1.40m from the shore line; monthly mortality rates and reproduction seasons of the species.

  7. Large-scale determinants of intestinal schistosomiasis and intermediate host snail distribution across Africa

    DEFF Research Database (Denmark)

    Stensgaard, Anna-Sofie; Utzinger, Jürg; Vounatsou, Penelope

    2013-01-01

    to climate change. Here, we combine a growing degree day model for Schistosoma mansoni with species distribution models for the intermediate host snail (Biomphalaria spp.) to investigate large-scale environmental determinants of the distribution of the African S. mansoni-Biomphalaria system and potential...... impacts of climatic changes. Snail species distribution models included several combinations of climatic and habitat-related predictors; the latter divided into "natural" and "human-impacted" habitat variables to measure anthropogenic influence. The predictive performance of the combined snail......-parasite model was evaluated against a comprehensive compilation of historical S. mansoni parasitological survey records, and then examined for two climate change scenarios of increasing severity for 2080. Future projections indicate that while the potential S. mansoni transmission area expands, the snail ranges...

  8. Acute Effects of (Bis)tributyltin Oxide on Marine Organisms. Summary of Work Performed 1981 to 1983

    Science.gov (United States)

    1989-05-01

    A-9 msm fjm ■ llll«UWIJiaiilHMlgiMMiWW»^fp«f^ 01 c t ro *-< c 0) > c c 3 r^ t-J o ra "ai ^ ra w (13 c v^. X) ro ü i_ y) y. o o c o o...Chronic Intoxication Effects of illtralow Molluscicide Concentra- tions on Lebistes reticulatus and Biomphalaria glahrata. Schistosomiasis Program Report

  9. Terpenes isolated of Coussarea platyphylla Muell. Arg. (Rubiaceae); Terpenos isolados de Coussarea platyphylla Muell. Arg. (Rubiaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Francieli Casassa Vieira de; Marques, Fabio Goncalves; Silva, Cleuza Conceicao da; Santin, Silvana Maria de Oliveira [Universidade Estadual de Maringa, PR (Brazil). Dept. de Quimica], e-mail: smoliveira@uem.br; Nakamura, Celso Vataru [Universidade Estadual de Maringa, PR (Brazil). Dept. de Microbiologia; Zamuner, Maria Lucilia Motinha [Universidade Estadual de Maringa, PR (Brazil). Dept. de Farmacia e Farmacologia; Souza, Maria Conceicao de [Universidade Estadual de Maringa, PR (Brazil). Dept. de Biologia

    2009-07-01

    The phytochemical investigation of Coussarea platyphylla led to the isolation of triterpenes betulonic and betulinic acid, monoterpenes monotropein and monotropein salt, the diterpene trans-phytol and steroids. The structures of the isolated compounds were assigned on the basis of spectroscopic data, including two-dimensional NMR methods. The antiproliferative properties against human cancer cell lines and molluscicidal activity against Biomphalaria glabrata of the crude methanolic extract and of its fractions were investigated. (author)

  10. Evaluation of the molluscicidal properties of Euphorbia splendens var. hislopii (n. e. b. (Euphorbiaceae - 1: experimental test in a lentic habitat

    Directory of Open Access Journals (Sweden)

    Nelymar Martineli Mendes

    1992-03-01

    Full Text Available The latex of Euphorbia splendens var. hislopii, at concentrations between 5 to 12 mg/l, kills 100% of the population of Biomphalaria glabrata in a lentic habitat, after 24 h. The lyophilized latex, stocked for 18 months, killed only 34.2% of the snails, at the concentration of 5 mg/l, and 96.0% at 12 mg/l. No lethal effect was observed among Pomacea haustrum exposed to the same concentrations of the molluscicide.

  11. Acetogenins in Annona muricata L. (annonaceae) leaves are potent molluscicides.

    Science.gov (United States)

    Luna, J De S; De Carvalho, J M; De Lima, M R F; Bieber, L W; Bento, Edson De S; Franck, X; Sant'ana, A E G

    2006-03-01

    An ethanolic extract of the leaves of Annona muricata was shown to be toxic to adult forms of the snail Biomphalaria glabrata (LC50 9.32 microg mL(-1)) and to larvae of the brine shrimp Artemia salina (LC50 0.49 microg mL(-1)). Activity-guided fractionation of the extract gave rise to a sample with high molluscicidal activity that contained the acetogenins, annonacin (90%), isoannonacin (6%) and goniothalamicin (4%).

  12. Terpenos isolados de Coussarea platyphylla Müll. Arg. (Rubiaceae Terpenes isolated of Coussarea platyphylla Müll. Arg. (Rubiaceae

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    Francieli Casassa Vieira de Araujo

    2009-01-01

    Full Text Available The phytochemical investigation of Coussarea platyphylla led to the isolation of triterpenes betulonic and betulinic acid, monoterpenes monotropein and monotropein salt, the diterpene trans-phytol and esteroids. The structures of the isolated compounds were assigned on the basis of spectroscopic data, including two-dimensional NMR methods. The antiproliferative properties against human cancer cell lines and molluscicidal activity against Biomphalaria glabrata of the crude methanolic extract and of its fractions were investigated.

  13. Planorbidae, Lymnaeidae and Physidae of Peru (Mollusca: Basommatophora

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    Paraense W Lobato

    2003-01-01

    Full Text Available In the course of several trips to Peru I had the opportunity of collecting topotypic specimens of Biomphalaria andecola (Orbigny, 1835, B. helophila (Orbigny, 1835, B. pucaraensis (Preston, 1909, Drepanotrema limayanum (Lesson, 1830, D. kermatoides (Orbigny, 1835, and Lymnaea viatrix Orbigny, 1835, besides B. tenagophila (Orbigny, 1835, Helisoma trivolvis (Say, 1817, H. duryi (Wetherby, 1879, Physa acuta Draparnaud, 1801, and seemingly P. peruviana Gray, 1828. B. pucaraensis is considered a junior synonym of B. peregrina (Orbigny, 1835.

  14. The complete chloroplast genome sequence of Gentiana lawrencei var. farreri (Gentianaceae and comparative analysis with its congeneric species

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    Peng-Cheng Fu

    2016-09-01

    Full Text Available Background The chloroplast (cp genome is useful in plant systematics, genetic diversity analysis, molecular identification and divergence dating. The genus Gentiana contains 362 species, but there are only two valuable complete cp genomes. The purpose of this study is to report the characterization of complete cp genome of G. lawrencei var. farreri, which is endemic to the Qinghai-Tibetan Plateau (QTP. Methods Using high throughput sequencing technology, we got the complete nucleotide sequence of the G. lawrencei var. farreri cp genome. The comparison analysis including genome difference and gene divergence was performed with its congeneric species G. straminea. The simple sequence repeats (SSRs and phylogenetics were studied as well. Results The cp genome of G. lawrencei var. farreri is a circular molecule of 138,750 bp, containing a pair of 24,653 bp inverted repeats which are separated by small and large single-copy regions of 11,365 and 78,082 bp, respectively. The cp genome contains 130 known genes, including 85 protein coding genes (PCGs, eight ribosomal RNA genes and 37 tRNA genes. Comparative analyses indicated that G. lawrencei var. farreri is 10,241 bp shorter than its congeneric species G. straminea. Four large gaps were detected that are responsible for 85% of the total sequence loss. Further detailed analyses revealed that 10 PCGs were included in the four gaps that encode nine NADH dehydrogenase subunits. The cp gene content, order and orientation are similar to those of its congeneric species, but with some variation among the PCGs. Three genes, ndhB, ndhF and clpP, have high nonsynonymous to synonymous values. There are 34 SSRs in the G. lawrencei var. farreri cp genome, of which 25 are mononucleotide repeats: no dinucleotide repeats were detected. Comparison with the G. straminea cp genome indicated that five SSRs have length polymorphisms and 23 SSRs are species-specific. The phylogenetic analysis of 48 PCGs from 12 Gentianales

  15. Malacological survey and geographical distribution of vector snails for schistosomiasis within informal settlements of Kisumu City, western Kenya

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    Opisa Selpha

    2011-12-01

    Full Text Available Abstract Background Although schistosomiasis is generally considered a rural phenomenon, infections have been reported within urban settings. Based on observations of high prevalence of Schistosoma mansoni infection in schools within the informal settlements of Kisumu City, a follow-up malacological survey incorporating 81 sites within 6 informal settlements of the City was conducted to determine the presence of intermediate host snails and ascertain whether active transmission was occurring within these areas. Methods Surveyed sites were mapped using a geographical information system. Cercaria shedding was determined from snails and species of snails identified based on shell morphology. Vegetation cover and presence of algal mass at the sites was recorded, and the physico-chemical characteristics of the water including pH and temperature were determined using a pH meter with a glass electrode and a temperature probe. Results Out of 1,059 snails collected, 407 (38.4% were putatively identified as Biomphalaria sudanica, 425 (40.1% as Biomphalaria pfeifferi and 227 (21.5% as Bulinus globosus. The spatial distribution of snails was clustered, with few sites accounting for most of the snails. The highest snail abundance was recorded in Nyamasaria (543 snails followed by Nyalenda B (313 snails. As expected, the mean snail abundance was higher along the lakeshore (18 ± 12 snails compared to inland sites (dams, rivers and springs (11 ± 32 snails (F1, 79 = 38.8, P Biomphalaria snails was higher in the inland (2.7% compared to the lakeshore sites (0.3% (P = 0.0109. B. sudanica was more abundant in sites along the lakeshore whereas B. pfeifferi and B. globosus were more abundant in the inland sites. Biomphalaria and Bulinus snails were found at 16 and 11 out of the 56 inland sites, respectively. Conclusions The high abundance of Biomphalaria and Bulinus spp. as well as observation of field-caught snails shedding cercariae confirmed that besides Lake

  16. The helminth community of Apodemus sylvaticus (Rodentia, Muridae in the Sierra de Gredos (Spain

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    Fuentes, M. V.

    2005-02-01

    Full Text Available The Spanish mountain range of Gredos was included in the studies conducted on the Iberian peninsula to investigate helminth fauna of small mammals. The helminth community of the wood mouse, Apodemus sylvaticus (Rodentia, Muridae, was analysed. Qualitatively, 13 helminth species were detected: Plagiorchis sp. I and Plagiorchis sp. II (Trematoda; Taenia parva larvae, T. martis larvae, T. taeniaeformis larvae, Rodentolepis straminea and R. fraterna (Cestoda; and Trichuris muris, Heligmosomoides polygyrus, Syphacia stroma, S. frederici, Aspiculuris tetraptera and Rictularia proni (Nematoda. Quantitatively, the highest prevalence (65.0% and the mean abundance (36.9% of H. polygyrus stand out. In comparison with the other mountain ranges studied, analysis of the global results demonstrates that the helminth fauna of the host species studied is diverse despite the adverse climatic conditions. This could be related to both the particular ecological characteristics and the appropriate state of preservation of this ecosystem.

  17. Avaliação da atividade moluscicida da Gymnema sylvestre R. Br., (Asclepiadaceae Evaluation of molluscicidal activity of Gymnema sylvestre R. Br., (Asclepiadaceae

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    Andréa Brustolin

    2000-05-01

    Full Text Available A Gymnema sylvestre R. Br. (Asclepiadaceae é uma trepadeira lenhosa nativa da Índia. As folhas são utilizadas na medicina popular como antidiabética, estomáquica, diurética refrigerante, adstringente e tônica. O extrato metanólico bruto e suas frações das partes aéreas foram utilizados para avaliar a atividade moluscicida de caramujos (Biomphalaria glabrata. O extrato metanólico bruto e suas frações foram analisados em cromatografia em camada delgada, determinados os índices hemolítico e de espuma; e realizados os ensaios físico-químicos das partes aéreas desta espécie. Das cinco frações obtidas do extrato metanólico bruto, a fração metanólica apresentou maior atividade moluscicida e demonstrou a presença de compostos hemolíticos em cromatografia de camada delgadaGymnema sylvestre R. Br. (Asclepiadaceae is a native plant found in India. The leaves are used in folk medicine as antidiabetic, stomachic, diuretic, astringent and tonic. The methanolic extract and fractions obtained from aerial parts were used to evaluate the molluscicidal activity against the snail (Biomphalaria glabrata. The methanolic extract and its fractions were analyzed by thin-layer chromatography, foam and the hemolitic index were measured, and the physical and chemical characteristics of aerial parts of this species were analyzed. The methanolic extract yielded five fractions, the methanolic fraction presented moluscicidal activity against Biomphalaria glabrata and showed content of hemolitic compound by thin-layer chromatography

  18. Bioactive plants from Argentina and Bolivia.

    Science.gov (United States)

    Bardón, Alicia; Borkosky, Susana; Ybarra, María I; Montanaro, Susana; Cartagena, Elena

    2007-04-01

    Antibacterial and molluscicidal activities of methanol and chloroform extracts of 16 plant species belonging to the families Compositae and Melastomataceae were evaluated. The chloroform extract of Vernonanthura tweediana and the methanol extract of Senecio santelisis resulted to be very toxic to brine shrimp nauplii (LC(50)=1 microg/ml). Chloroform extracts of S. santelisis and Senecio leucostachys as well as the methanol extract of Wedelia subvaginata displayed molluscicidal effects on Biomphalaria peregrina showing LC(100)Grindelia scorzonerifolia and Vernonia incana against two strains of Staphylococcus aureus.

  19. Evaluation of the molluscicidal property of Euphorbia splendens var. Hispolii (N.E.B. (Euphorbiaceae: 2. Investigation in lotic habitat

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    D. F. Baptista

    1992-12-01

    Full Text Available The latex of Euphorbia splendens var. hispolii in 12 ppm concentration (12 mg/l caused 100% mortality for a Biomphalaria tenagophila population in a lotic habitat after 9 hr of dripfeed application. For sentinel snails, in cages placed at the water surface and buried under 0.10 m, the mortality rates varied with the distance from the application point and were: 100% (0 m; 92.6% (50 m and 94.7% (100. No lethal effects were observed for the other living species in this habitat (Pomacea haustrum and Poecilia reticulata.

  20. Molluscicidal acridone alkaloids from Angostura paniculata: isolation, structures, and synthesis.

    Science.gov (United States)

    Vieira, P C; Kubo, I; Kujime, H; Yamagiwa, Y; Kamikawa, T

    1992-08-01

    Two novel acridone alkaloids, cuspanine [1] and cusculine [2], were isolated from the CH2Cl2 extract of the leaves of Angostura paniculata (Rutaceae). Their structures were established as 1-hydroxy-2,3,5,6-tetramethoxy-9-acridone for 1 and 1,2,3,5,6-pentamethoxy-9-acridone for 2 by means of spectroscopic studies, in particular nmr. These structural assignments were confirmed by synthesis, using a direct metallation method as a key reaction. Both alkaloids exhibited moderate molluscicidal activity against an aquatic snail, Biomphalaria glabrata, and cytotoxicity against several types of carcinoma cell lines.

  1. Modeling the potential distribution of the invasive golden mussel Limnoperna fortunei in the Upper Paraguay River system using limnological variables

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    MD Oliveira

    Full Text Available The invasive golden mussel, Limnoperna fortunei (Dunker, 1857, was introduced into the La Plata River estuary and quickly expanded upstream to the North, into the Paraguay and Paraná rivers. An ecological niche modeling approach, based on limnological variables, was used to predict the expansion of the golden mussel in the Paraguay River and its tributaries. We used three approaches to predict the geographic distribution: 1 the spatial distribution of calcium concentration and the saturation index for calcium carbonate (calcite; 2 the Genetic Algorithm for Rule-Set Production (GARP model; and the 3 Maximum Entropy Method (Maxent model. Other limnological variables such as temperature, dissolved oxygen, pH, and Total Suspended Solids (TSS were used in the latter two cases. Important tributaries of the Paraguay River such as the Cuiabá and Miranda/Aquidauana rivers exhibit high risk of invasion, while lower risk was observed in the chemically dilute waters of the middle basin where shell calcification may be limited by low calcium concentrations and carbonate mineral undersaturation.

  2. Size-selective predation of the catfish Pimelodus pintado (Siluriformes: Pimelodidae on the golden mussel Limnoperna fortunei (Bivalvia: Mytilidae

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    João P. Vieira

    2013-02-01

    Full Text Available This paper describes the size-selective predation on Limnoperna fortunei (Dunker, 1857 by Pimelodus pintado (Azpelicueta, Lundberg & Loureiro, 2008 from the time it arrived at the Mirim Lagoon basin (2005. Sampling was carried out using bottom trawl in depths of 3-6 m, from January to November 2005, and from October to November 2008. Pimelodus pintado began to prey upon L. fortunei soon after its arrival (austral spring of 2005. On the spring of 2008, L. fortunei was found to be the most important food item of P. pintado. The variation in length of the mussels (0.7-3.2 cm, with a mode of 1.3 cm indicates that the species is now fully established in the system. Our data indicates that large individuals of P. pintado incorporate more mussels in their diets than small individuals. However, regardless of their size, P. pintado individuals predate only on small (<1.4 cm representatives of L. fortunei. This prey size corresponds to a phase when the mussel is more mobile and readily available for fish. Larger, more aggregated prey groups that are attached to hard substrates are avoided by fish predators.

  3. Modeling the potential distribution of the invasive golden mussel Limnoperna fortunei in the Upper Paraguay River system using limnological variables.

    Science.gov (United States)

    Oliveira, M D; Hamilton, S K; Calheiros, D F; Jacobi, C M; Latini, R O

    2010-10-01

    The invasive golden mussel, Limnoperna fortunei (Dunker, 1857), was introduced into the La Plata River estuary and quickly expanded upstream to the North, into the Paraguay and Paraná rivers. An ecological niche modeling approach, based on limnological variables, was used to predict the expansion of the golden mussel in the Paraguay River and its tributaries. We used three approaches to predict the geographic distribution: 1) the spatial distribution of calcium concentration and the saturation index for calcium carbonate (calcite); 2) the Genetic Algorithm for Rule-Set Production (GARP) model; and the 3) Maximum Entropy Method (Maxent) model. Other limnological variables such as temperature, dissolved oxygen, pH, and Total Suspended Solids (TSS) were used in the latter two cases. Important tributaries of the Paraguay River such as the Cuiabá and Miranda/Aquidauana rivers exhibit high risk of invasion, while lower risk was observed in the chemically dilute waters of the middle basin where shell calcification may be limited by low calcium concentrations and carbonate mineral undersaturation.

  4. Cognitive maps across cultures and across sciences.

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    Horacio J. A. Rimoldi

    2004-01-01

    Full Text Available En el presente trabajo se discuten aquellas investigaciones que se refieren a la forma con la cual los sujetos buscan y procesan la información. Este tema fue estudiado tiempo ha por los psicólogos de la Gestalt (Kohler, Wertheimer, Dunker y por algunos matemáticos tales como Polya, Russel, Whitehead. Tempranas investigaciones acerca de la resolución de problemas llevaron al estudio y aprendizaje del adiestramiento en medicina. Luego, el concepto de isomorfismo fue investigado a través de diferentes sistemas de relaciones que rigen en distintas ciencias y medios culturales. El estudio de los procesos llevó a considerar el orden como un componente fundamental, que requiere nuevos métodos para apreciar cómo el orden en que se da la información, en la secuencia de acontecimientos que identifica una táctica, influye en los resultados. Así se desarrolló el sistema de puntaje que maximiza la evaluación de la eficiencia en la resolución de problemas.

  5. Green Fluorescence of Cytaeis Hydroids Living in Association with Nassarius Gastropods in the Red Sea.

    Science.gov (United States)

    Prudkovsky, Andrey A; Ivanenko, Viatcheslav N; Nikitin, Mikhail A; Lukyanov, Konstantin A; Belousova, Anna; Reimer, James D; Berumen, Michael L

    2016-01-01

    Green Fluorescent Proteins (GFPs) have been reported from a wide diversity of medusae, but only a few observations of green fluorescence have been reported for hydroid colonies. In this study, we report on fluorescence displayed by hydroid polyps of the genus Cytaeis Eschscholtz, 1829 (Hydrozoa: Anthoathecata: Filifera) found at night time in the southern Red Sea (Saudi Arabia) living on shells of the gastropod Nassarius margaritifer (Dunker, 1847) (Neogastropoda: Buccinoidea: Nassariidae). We examined the fluorescence of these polyps and compare with previously reported data. Intensive green fluorescence with a spectral peak at 518 nm was detected in the hypostome of the Cytaeis polyps, unlike in previous reports that reported fluorescence either in the basal parts of polyps or in other locations on hydroid colonies. These results suggest that fluorescence may be widespread not only in medusae, but also in polyps, and also suggests that the patterns of fluorescence localization can vary in closely related species. The fluorescence of polyps may be potentially useful for field identification of cryptic species and study of geographical distributions of such hydroids and their hosts.

  6. Green Fluorescence of Cytaeis Hydroids Living in Association with Nassarius Gastropods in the Red Sea.

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    Andrey A Prudkovsky

    Full Text Available Green Fluorescent Proteins (GFPs have been reported from a wide diversity of medusae, but only a few observations of green fluorescence have been reported for hydroid colonies. In this study, we report on fluorescence displayed by hydroid polyps of the genus Cytaeis Eschscholtz, 1829 (Hydrozoa: Anthoathecata: Filifera found at night time in the southern Red Sea (Saudi Arabia living on shells of the gastropod Nassarius margaritifer (Dunker, 1847 (Neogastropoda: Buccinoidea: Nassariidae. We examined the fluorescence of these polyps and compare with previously reported data. Intensive green fluorescence with a spectral peak at 518 nm was detected in the hypostome of the Cytaeis polyps, unlike in previous reports that reported fluorescence either in the basal parts of polyps or in other locations on hydroid colonies. These results suggest that fluorescence may be widespread not only in medusae, but also in polyps, and also suggests that the patterns of fluorescence localization can vary in closely related species. The fluorescence of polyps may be potentially useful for field identification of cryptic species and study of geographical distributions of such hydroids and their hosts.

  7. GESTÃO DA INOVAÇÃO SUSTENTÁVEL: UM ESTUDO DE CASO EM UMA EMPRESA DE FERTIZANTES BIOLÓGICOS

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    Melhores Trabalhos .

    2015-02-01

    Full Text Available O presente buscou identificar como ocorre a gestão da inovação sustentável em uma empresa de fertilizantes biológicos, tendo como base nos  modelos de Tidd, Bessant e Pavitt (2008  e Hansen, Grosse-Dunker e Reichwald (2009. Mais especificamente foi explorada uma empresa de fertilizantes Biológicos de Cruz Alta/RS,  premiada em 2013 no prêmio Vencedores do Agronegócio. Os dados do estudo, de caráter qualitativo e descritivo, foram obtidos a partir de entrevistas semiestruturadas com o gestor da empresa e complementados por dados secundários publicados em  web site  da empresa. As análises de conteúdo dos dados obtidos evidenciaram a existência da prática de Gestão da Inovação Sustentável uma vez que a empresa trabalha com produtos 100% naturais, inovadores e sustentáveis,  e possui parcerias com stakeholders para geração de tecnologia e investimentos em produtos. No entanto a empresa necessita ampliação no sistema de produto-serviço e da comunicação dos benefícios do produto.

  8. Green Fluorescence of Cytaeis Hydroids Living in Association with Nassarius Gastropods in the Red Sea

    KAUST Repository

    Prudkovsky, Andrey A.

    2016-02-03

    Green Fluorescent Proteins (GFPs) have been reported from a wide diversity of medusae, but only a few observations of green fluorescence have been reported for hydroid colonies. In this study, we report on fluorescence displayed by hydroid polyps of the genus Cytaeis Eschscholtz, 1829 (Hydrozoa: Anthoathecata: Filifera) found at night time in the southern Red Sea (Saudi Arabia) living on shells of the gastropod Nassarius margaritifer (Dunker, 1847) (Neogastropoda: Buccinoidea: Nassariidae). We examined the fluorescence of these polyps and compare with previously reported data. Intensive green fluorescence with a spectral peak at 518 nm was detected in the hypostome of the Cytaeis polyps, unlike in previous reports that reported fluorescence either in the basal parts of polyps or in other locations on hydroid colonies. These results suggest that fluorescence may be widespread not only in medusae, but also in polyps, and also suggests that the patterns of fluorescence localization can vary in closely related species. The fluorescence of polyps may be potentially useful for field identification of cryptic species and study of geographical distributions of such hydroids and their hosts.

  9. Data supporting functional diversity of the marine bacterium Cobetia amphilecti KMM 296

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    Larissa Balabanova

    2016-09-01

    Full Text Available Data is presented in support of functionality of hyper-diverse protein families encoded by the Cobetia amphilecti KMM 296 (formerly Cobetia marina KMM 296 genome (“The genome of the marine bacterium Cobetia marina KMM 296 isolated from the mussel Crenomytilus grayanus (Dunker, 1853” [1] providing its nutritional versatility, adaptability and biocontrol that could be the basis of the marine bacterium evolutionary and application potential. Presented data include the information of growth and biofilm-forming properties of the food-associated isolates of Pseudomonas, Bacillus, Listeria, Salmonella and Staphylococcus under the conditions of their co-culturing with C. amphilecti KMM 296 to confirm its high inter-species communication and anti-microbial activity. Also included are the experiments on the crude petroleum consumption by C. amphilecti KMM 296 as the sole source of carbon in the presence of sulfate or nitrate to ensure its bioremediation capacity. The multifunctional C. amphilecti KMM 296 genome is a promising source for the beneficial psychrophilic enzymes and essential secondary metabolites.

  10. Levantamento malacológico da Bacia Hidrográfica do Lago Soledade, Ouro Branco, (Minas Gerais, Brasil Malacological survey at the Soledade Lake, in Ouro Branco (Minas Gerais, Brazil

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    Roney Elias da Silva

    1994-10-01

    Full Text Available Em estudo malacológico realizado na Bacia Hidrográfica do Lago Soledade, Ouro Branco, MG, no período de setembro de 1986 a março de 1991, foram coletados 46.579 moluscos, representados por 07 espécies de 05 famílias. Foram coletados 39.176 exemplares de Biomphalaria tenagophila, 1.296 de B. glabrata, sete exemplares de Drepanotrema cimex, 2.527 de Physa sp, 417 de Lymnaea sp, 92 de Pomacea haustrum e, a partir de março/1990, 3.064 exemplares de Melanoides tuberculata (Melanniidae = Thiaridae. Dos moluscos que apresentaram positividade para diversas larvas de trematódeos, quatro exemplares de B. tenagophila estavam positivos para S. mansoni.A malacological survey was carried out at the Soledade Lake, in Ouro Branco, State of Minas Gerais, for the period 1986-1991. A total amount of 46,579 mollusks was collected, and among them seven species corresponding to five families could be found, as follows: 39,176 specimens of Biomphalaria tenagophila; 1,296 B. glabrata; 7 Drepanotrema cimex; 2,527 Physa sp; 417 Lymnaea sp; 92 Pomacea hastrum, and 3,064 specimens of Melanoides tuberculata (Melanniidae=Thiaridae were collected from March/1990 onwards. Four specimens of B. tenagophila were found to be positive for Schistosoma mansoni.

  11. Experimental Evaluation of the Pathogenicity of Different Strains of Schistosoma mansoni

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    Antônio Aurélio Euzébio

    2012-01-01

    Full Text Available The pathogenesis of three different Schistosoma mansoni strains from the Brazilian states of Minas Gerais (BH strain and São Paulo (SJ and SD strains was evaluated in experimentally infected mice. Observations of the most severe clinical cases among local patients treated (SD strain in the city of Campinas (São Paulo, Brazil formed the basis of this study. Mice were used as definitive hosts and were infected with cercariae from Biomphalaria tenagophila (SJ and SD strains and Biomphalaria glabrata (BH strains. The parameters analyzed were as follows: number of S. mansoni eggs in mice feces; number of granulomas per tissue area in liver, spleen, lungs, pancreas, and ascending colon; measurements of hepatic and intestinal granulomas; number of adult worms; and measurements of trematode eggs. The comparison among the three strains indicated that the SD strain, isolated in Campinas, presented a higher worm recovery relative to the number of penetrating cercariae. In addition, when compared to the SJ and BH strains, the SD strain demonstrated similar pathogenicity to the BH strain, with a greater quantity of granulomas in the viscera, as well as larger granulomas and eggs. Furthermore, a greater quantity of trematode eggs was also shed in the feces.

  12. Experimental Evaluation of the Pathogenicity of Different Strains of Schistosoma mansoni.

    Science.gov (United States)

    Euzébio, Antônio Aurélio; Zuim, Nádia Regina Borim; Linhares, Arício Xavier; Magalhães, Luiz Augusto; Zanotti-Magalhães, Eliana Maria

    2012-01-01

    The pathogenesis of three different Schistosoma mansoni strains from the Brazilian states of Minas Gerais (BH strain) and São Paulo (SJ and SD strains) was evaluated in experimentally infected mice. Observations of the most severe clinical cases among local patients treated (SD strain) in the city of Campinas (São Paulo, Brazil) formed the basis of this study. Mice were used as definitive hosts and were infected with cercariae from Biomphalaria tenagophila (SJ and SD strains) and Biomphalaria glabrata (BH strains). The parameters analyzed were as follows: number of S. mansoni eggs in mice feces; number of granulomas per tissue area in liver, spleen, lungs, pancreas, and ascending colon; measurements of hepatic and intestinal granulomas; number of adult worms; and measurements of trematode eggs. The comparison among the three strains indicated that the SD strain, isolated in Campinas, presented a higher worm recovery relative to the number of penetrating cercariae. In addition, when compared to the SJ and BH strains, the SD strain demonstrated similar pathogenicity to the BH strain, with a greater quantity of granulomas in the viscera, as well as larger granulomas and eggs. Furthermore, a greater quantity of trematode eggs was also shed in the feces.

  13. A geoprocessing approach for studying and controlling schistosomiasis in the state of Minas Gerais, Brazil

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    Ricardo José de Paula Souza Guimarães

    2010-07-01

    Full Text Available Geographical information systems (GIS are tools that have been recently tested for improving our understanding of the spatial distribution of disease. The objective of this paper was to further develop the GIS technology to model and control schistosomiasis using environmental, social, biological and remote-sensing variables. A final regression model (R² = 0.39 was established, after a variable selection phase, with a set of spatial variables including the presence or absence of Biomphalaria glabrata, winter enhanced vegetation index, summer minimum temperature and percentage of houses with water coming from a spring or well. A regional model was also developed by splitting the state of Minas Gerais (MG into four regions and establishing a linear regression model for each of the four regions: 1 (R² = 0.97, 2 (R² = 0.60, 3 (R² = 0.63 and 4 (R² = 0.76. Based on these models, a schistosomiasis risk map was built for MG. In this paper, geostatistics was also used to make inferences about the presence of Biomphalaria spp. The result was a map of species and risk areas. The obtained risk map permits the association of uncertainties, which can be used to qualify the inferences and it can be thought of as an auxiliary tool for public health strategies.

  14. Estudos sobre o comportamento dos Planorbídeos: I - uma técnica de observação e registro comportamental por cinematografia Studies on the behavior of planorbids: I - a technique for behavioral observation and recording by use of cinematography

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    Otávio S. Pieri

    1980-01-01

    Full Text Available Uma técnica envolvendo cinematografia com lapso de tempo foi elaborada para o estudo da atividade comportamental dos planorbídeos em condições de laboratório. As observações realizam-se em uma câmara dotada de ciclo de iluminação dia-noite, e os registros são feitos com uma filmadora super-8, operada quadro a quadro, sob luz de flash estroboscópico. Essa técnica tem permitido mensurações rigorosas de diferentes aspectos do comportamento de Biomphalaria glabrata (say, 1818, e pode ser utilizada na análise do nível de resposta dos planorbídeos aos moluscicidas, em testes experimentais, e dos comportamentos de proteção frente a condições adversas em geral.A technique involving time-lapse cinematography was developed for studying the behavioral repertoire of planorbids in laboratory conditions. Observations were carried out within a chamber with controlled light and temperature; recording was done by single frame shooting at 10 second intervals, with synchronized strobed flash. This technique has allowed accurate measurements of different aspects of the activity of Biomphalaria glabrata (Say, 1818, and can be useful in analysing the level of response of planorbids to molluscicides, in experimental tests, as well as their protective behavior under general adverse conditions.

  15. Molluscicidal activity of 2-hydroxy-[1,4]naphthoquinone and derivatives

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    Celso A. Camara

    2008-06-01

    Full Text Available The toxic profile of lawsone (2-hydroxy-[1,4]naphthoquinone and a series of [1,4]naphthoquinone derivatives was evaluated against the brine shrimp Artemia salina and against the mollusk Biomphalaria glabrata, the main transmitting vector of schistosomiasis in Brazil. Of the seventeen compounds tested nine fell below the threshold of 100 µg/mL set for potential molluscicidal activity by the World Health Organization. As a general rule derivatives with non-polar substituents presented the highest molluscicidal activities. These substances showed significant toxicity in A. salina lethality bioassay.A toxicidade da lausona (2-hidroxi-1,4-naftoquinona e de diversos derivados foi avaliada frente à Artemia salina e ao molusco Biomphalaria glabrata, o principal vetor de transmissão da esquistossomose no Brasil. Entre os dezessete compostos testados, nove apresentaram um perfil de toxicidade menor que 100 µg/mL, sendo potenciais agentes moluscicidas de acordo com as designações da Organização Mundial da Saúde. No presente estudo, os compostos contendo substituintes apolares exibiram as maiores atividades. Estes compostos também se mostraram significantemente tóxicos frente à A. salina.

  16. Lymnaea columella: two new Brazilian localities in the states of Amazonas and Bahia

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    W. Lobato Paraense

    1986-03-01

    Full Text Available The occurrence of Lymnaea columella is recorded in Tefé, Amazonas state, where it was found together with Drepanotrema anatinum, Physa marmorata and pomacea sp. L. columella was also collected in Salvador, Bahia state, at the dique do Tororó, an urban lake formely mentioned (as "lac Baril" by Moricand (1853 as a breeding-place of Biomphalaria glabrata, Drepanotrema cimex, D. depressissimum, Pomacea lineata, P. decussata and Ancylus moricandi. The four first-mentioned species, as well as physa cubensis and Hemisinus brasiliensis, were also collected now. This is the first record of a lymnaeid in the Northeastern region of Brazil.É registrada a ocorrência de Lymnaea columella em Tefé, Estado do Amazonas, onde foi encontrada juntamente com Physa marmorata e Pomacea sp. L. columella foi também coletada em Salvador, Estado da Bahia, no Dique do Tororó, lago urbano antes mencionado por Moricand (1853 como criadouro de Biomphalaria glabrata, Drepanotrema cimex, D. depressissimum, Pomacea lineata, P. decussata e Ancylus moricandi. As quatro primeiras espécies mencionadas, assim como Physa cubensis e Hemisinus brasiliensis, também foram agora coletadas. Este é o primeiro registro de um limneídeo na região Nordeste do Brasil

  17. Experimental evaluation of Odonata nymph in the biocontrol of schistosomiasis intermediate hosts

    Institute of Scientific and Technical Information of China (English)

    Aly Younes; Hanaa El-Sherief; Fathia Gawish; Marwa Mahmoud

    2016-01-01

    Objective: To evaluate the predatory potential of the Odonata nymph on freshwater snails that serve as intermediate hosts for Schistosoma species (Bulinus truncatus and Biomphalaria alexandrina). Methods: Observations on the searching, attacking and devouring of the two snail types with series of laboratory-based predation experiments, whose aims were to determine daily predation rate, differential predation, prey preference considering small-, medium-and large-sized snails were conducted. Results: Laboratory evaluation revealed that, the Odonata nymph could kill and consume the two intermediate hosts. The number of snails consumed differed according to the snail type, size and density. The times taken for searching and handling times were dependent on the snail size, type and satiation of the predator. The predation rate varied also with respect to snail type, size and density. This study also evaluated that Odonata nymphs consumed more Bulinus truncatus than Biomphalaria alexandrina per unit time, and that there may be a preference for smaller than larger snails. Conclusions: According to our observation, the predator, Hemianax ephippiger nymph may be a suitable biocontrol agent in connection with Schistosoma intermediate hosts.

  18. Revisión y bionomía del género Syncirsodes Butler 1882 (Lepidoptera: Geometridae Revision and bionomy of the genus Syncirsodes Butler 1882 (Lepidoptera: Geometridae

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    PATRICIA A. BOCAZ

    2005-03-01

    Full Text Available El género Syncirsodes Butler 1882, es redefinido y las especies son taxonómicamente revisadas y redescritas. Las especies que conforman el género son las siguientes: S. primata (Walker 1862, S. subornata (Walker 1863, S. straminea (Butler 1882, S. distictaria (Mabille 1885 y S. hyadesi (Mabille 1885. El ejemplar alotipo de la especie A. primata Walker (1862 corresponde a la hembra de S. distictaria. Las especies deustata Felder & Rogenhofer (1875 y arenosa, carnea, cinerea, squamosa y turbida descritas por Butler (1882 son los sinónimos junior de S. primata Walker (1862. La ausencia de la armadura genital del material tipo y la falta de otros ejemplares nos hace mantener como válida la especie S. subornata. El género se distribuye principalmente en la región Andina, solo S. subornata se encuentra en la provincia Pampa. Se describen además los estados inmaduros y la bionomía de S. distictaria y S. primata. Se entregan claves, dibujos de la genitalia, la distribución y fotografías de las diferentes especiesThe genus Syncirsodes Butler 1882 is redefined and its species are taxonomically revised and described. The species are as follows: S. distictaria (Mabille 1885, S. primata (Walker 1862, S. hyadesi (Mabille 1885, S. straminea (Butler 1882 and S. subornata (Walker 1863. The specimen allotype of A. primata Walker (1862 corresponds to the female of S. distictaria. The species deustata Felder & Rogenhofer (1875 and arenosa, carnea, cinerea, squamosa and turbida described by Butler (1882 are junior synonyms of S. primata Walker (1862. The absence of the genitalia of the type and the lack of other specimens make us maintain to S. subornata as a valid species. The genus is distributed mainly in the Andean region, only S. subornata is in the Pampa province. Immature stages and bionomy of S. distictaria and S. primata are described, and an identification key, data on the distribution as well illustrations of the adult moths are provided

  19. DNA sequence-based analysis of the Pseudomonas species.

    Science.gov (United States)

    Mulet, Magdalena; Lalucat, Jorge; García-Valdés, Elena

    2010-06-01

    Partial sequences of four core 'housekeeping' genes (16S rRNA, gyrB, rpoB and rpoD) of the type strains of 107 Pseudomonas species were analysed in order to obtain a comprehensive view regarding the phylogenetic relationships within the Pseudomonas genus. Gene trees allowed the discrimination of two lineages or intrageneric groups (IG), called IG P. aeruginosa and IG P. fluorescens. The first IG P. aeruginosa, was divided into three main groups, represented by the species P. aeruginosa, P. stutzeri and P. oleovorans. The second IG was divided into six groups, represented by the species P. fluorescens, P. syringae, P. lutea, P. putida, P. anguilliseptica and P. straminea. The P. fluorescens group was the most complex and included nine subgroups, represented by the species P. fluorescens, P. gessardi, P. fragi, P. mandelii, P. jesseni, P. koreensis, P. corrugata, P. chlororaphis and P. asplenii. Pseudomonas rhizospherae was affiliated with the P. fluorescens IG in the phylogenetic analysis but was independent of any group. Some species were located on phylogenetic branches that were distant from defined clusters, such as those represented by the P. oryzihabitans group and the type strains P. pachastrellae, P. pertucinogena and P. luteola. Additionally, 17 strains of P. aeruginosa, 'P. entomophila', P. fluorescens, P. putida, P. syringae and P. stutzeri, for which genome sequences have been determined, have been included to compare the results obtained in the analysis of four housekeeping genes with those obtained from whole genome analyses.

  20. Phylogenetic diversity of Moroccan cork oak woodlands fungi

    Directory of Open Access Journals (Sweden)

    Abourouh M.

    2009-01-01

    Full Text Available Interspecific variation among 87 sporocarps of fungi belonging to 15 genera and 39 species were evaluated by analyzing the internal transcribed spacer (ITS of the rDNA region using restriction fragment length polymorphism (RFLP. The ITS region was first amplified by polymerase chain reaction (PCR with specific primers and then cleaved with different restriction enzymes. Amplification products, which ranged between 500 and 950 base pairs (bp, were obtained for all the isolates analyzed. The degree of polymorphism observed did not allow proper identification of most of the species. Cleavage of amplified fragments with the restriction enzymes Alu I, EcoR I and Hinf I revealed extensive polymorphism. The fifteen genera and most species presented specific restriction patterns. The only species not identifiable by a specific pattern belonged to the genera Russula (R. decipiens and R. straminea. These species might be considered as closely related species. The Pisolithus sporocarps had two ITS-RFLP types with one dominating. ITS sequencing confirms that the two RFLP types correspond to two distinct species of Pisolithus. Our data show the potential of ITS region PCR-RFLP for the molecular characterization of ectomycorrhizal fungi and their identification and monitoring in artificial inoculation programs.

  1. Efeitos biológicos da Pfaffia glomerata (Spreng. Pedersen e da Pfaffia paniculata (Martius Kuntze (Amaranthaceae Biological effects of Pfaffia glomerata (Spreng. Pedersen and Pfaffia paniculata (Martius Kuntze (Amaranthaceae

    Directory of Open Access Journals (Sweden)

    Diógenes Aparício Garcia Cortez

    1999-07-01

    Full Text Available A Pfaffia glomerata (Spreng. Pedersen e da Pfaffia paniculata (Martius Kuntze (Amaranthaceae são plantas nativas da região alagada das ilhas de Porto Rico, Paraná, Brasil. São utilizadas na medicina popular como tônico, afrodisíaco e antidiabético. O extrato bruto metanólico, obtido das raízes das duas espécies, foi utilizado para avaliar a atividade moluscicida de caramujos (Biomphalaria glabrata. Além disso, o potencial hipoglicemiante da Pfaffia glomerata foi investigado em ratos tratados com aloxana. As saponinas do extrato bruto metanólico da P. glomerata e da P. paniculata foram analisadas em cromatografia em camada delgada e foi determinado o índice hemolítico. O extrato bruto metanólico obtido da Pfaffia glomerata apresentou maior conteúdo de saponinas hemolíticas e maior atividade moluscicida em relação à Pfaffia paniculata. Todavia, o tratamento com extrato de Pfaffia glomerata não promoveu efeitos significativos sobre os níveis glicêmicos.Pfaffia glomerata (Spreng. Pedersen. (Amaranthaceae and Pfaffia paniculata (Martius Kuntze are native plants found in the flooded area of the islands of Porto Rico, state of Paraná, Brazil. They are used in folk medicine as tonics, aphrodisiacs, and to treat diabetes. The methanolic extract obtained from roots of both species was used to evaluate the molluscicidal activity against the periwinkle Biomphalaria glabrata and the hypoglycemic activity of Pfaffia glomerata was investigated in rats with diabetes induced by alloxan. The saponins from the methanolic extract of P. glomerata and P. paniculata were analyzed by thin-layer chromatography and scum and the hemolitic index was measured. The methanolic extract obtained from Pfaffia glomerata showed higher content of hemolytic saponin than Pfaffia paniculata and presented molluscicidal activity against Biomphalaria glabrata from 200 ppm. However, the treatment with P. glomerata extract did not promote any significant effect on

  2. Climate change, genetics or human choice: why were the shells of mankind's earliest ornament larger in the pleistocene than in the holocene?

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    Peter R Teske

    Full Text Available BACKGROUND: The southern African tick shell, Nassarius kraussianus (Dunker, 1846, has been identified as being the earliest known ornamental object used by human beings. Shell beads dated from approximately 75,000 years ago (Pleistocene era were found in a cave located on South Africa's south coast. Beads made from N. kraussianus shells have also been found in deposits in this region dating from the beginning of the Holocene era (<10,000 years ago. These younger shells were significantly smaller, a phenomenon that has been attributed to a change in human preference. METHODOLOGY/PRINCIPAL FINDINGS: We investigated two alternative hypotheses explaining the difference in shell size: a N. kraussianus comprises at least two genetic lineages that differ in size; b the difference in shell size is due to phenotypic plasticity and is a function of environmental conditions. To test these hypotheses, we first reconstructed the species' phylogeographic history, and second, we measured the shell sizes of extant individuals throughout South Africa. Although two genetic lineages were identified, the sharing of haplotypes between these suggests that there is no genetic basis for the size differences. Extant individuals from the cool temperate west coast had significantly larger shells than populations in the remainder of the country, suggesting that N. kraussianus grows to a larger size in colder water. CONCLUSION/SIGNIFICANCE: The decrease in fossil shell size from Pleistocene to Holocene was likely due to increased temperatures as a result of climate change at the beginning of the present interglacial period. We hypothesise that the sizes of N. kraussianus fossil shells can therefore serve as indicators of the climatic conditions that were prevalent in a particular region at the time when they were deposited. Moreover, N. kraussianus could serve as a biomonitor to study the impacts of future climate change on coastal biota in southern Africa.

  3. 2K09 and thereafter : the coming era of integrative bioinformatics, systems biology and intelligent computing for functional genomics and personalized medicine research.

    Science.gov (United States)

    Yang, Jack Y; Niemierko, Andrzej; Bajcsy, Ruzena; Xu, Dong; Athey, Brian D; Zhang, Aidong; Ersoy, Okan K; Li, Guo-Zheng; Borodovsky, Mark; Zhang, Joe C; Arabnia, Hamid R; Deng, Youping; Dunker, A Keith; Liu, Yunlong; Ghafoor, Arif

    2010-12-01

    Significant interest exists in establishing synergistic research in bioinformatics, systems biology and intelligent computing. Supported by the United States National Science Foundation (NSF), International Society of Intelligent Biological Medicine (http://www.ISIBM.org), International Journal of Computational Biology and Drug Design (IJCBDD) and International Journal of Functional Informatics and Personalized Medicine, the ISIBM International Joint Conferences on Bioinformatics, Systems Biology and Intelligent Computing (ISIBM IJCBS 2009) attracted more than 300 papers and 400 researchers and medical doctors world-wide. It was the only inter/multidisciplinary conference aimed to promote synergistic research and education in bioinformatics, systems biology and intelligent computing. The conference committee was very grateful for the valuable advice and suggestions from honorary chairs, steering committee members and scientific leaders including Dr. Michael S. Waterman (USC, Member of United States National Academy of Sciences), Dr. Chih-Ming Ho (UCLA, Member of United States National Academy of Engineering and Academician of Academia Sinica), Dr. Wing H. Wong (Stanford, Member of United States National Academy of Sciences), Dr. Ruzena Bajcsy (UC Berkeley, Member of United States National Academy of Engineering and Member of United States Institute of Medicine of the National Academies), Dr. Mary Qu Yang (United States National Institutes of Health and Oak Ridge, DOE), Dr. Andrzej Niemierko (Harvard), Dr. A. Keith Dunker (Indiana), Dr. Brian D. Athey (Michigan), Dr. Weida Tong (FDA, United States Department of Health and Human Services), Dr. Cathy H. Wu (Georgetown), Dr. Dong Xu (Missouri), Drs. Arif Ghafoor and Okan K Ersoy (Purdue), Dr. Mark Borodovsky (Georgia Tech, President of ISIBM), Dr. Hamid R. Arabnia (UGA, Vice-President of ISIBM), and other scientific leaders. The committee presented the 2009 ISIBM Outstanding Achievement Awards to Dr. Joydeep Ghosh (UT

  4. Compatibility and sex in a snail-schistosome system.

    Science.gov (United States)

    Webster, J P

    2001-04-01

    Knowledge of the genetics underlying resistance to parasitic infection has important repercussions for our understanding of infection dynamics and the mechanisms of host-parasite co-evolution. The aim here was to determine for a Biomphalaria glabrato-Schistosoma mansoni system whether (1) resistance is dominant over susceptibility, (2) it is possible to crossbreed snails to be simultaneously resistant and/or susceptible to more than one parasite strain and (3) compatibility genotype affects reproductive strategy. Using replicate snail strains artificially selected for either resistance or susceptibility to single replicate parasite strains, individual snails from each line were paired with a selected partner of matched or non-matched compatibility status and cross-breeding was identified by RAPD-PCR. The resulting compatibility phenotype of all offspring was determined. Support for all 3 hypotheses were obtained. The results are discussed in terms of their applied and theoretical implications.

  5. [Molluscacide activity of a mixture of 6-n-alkyl salicylic acids (anacardic acid) and 2 of its complexes with copper (II) and lead (II)].

    Science.gov (United States)

    Mendes, N M; de Oliveira, A B; Guimarães, J E; Pereira, J P; Katz, N

    1990-01-01

    The molluscicide activity of hexanic extract from Anacardium occidentale L. (cashew) nut shell, of copper (II) complex, of lead (II) complex and anacardic acid has been compared in the laboratory in an attempt to obtain better stability than anacardic acid. This was obtained from the hexanic extract of the cashew nut shell by precipitation with lead (II) hydroxide or cupric sulfate plus sodium hydroxide or (II) cupric hydroxide followed by treatment of lead (II) complex with a diluted solution of sulfuric acid. Ten products of the mixture obtained were tested on adults snails of Biomphalaria glabrata at 1 to 10 ppm. The most active products were copper (II) complex, obtained by cupric sulfate plus sodium hydroxide, and anacardic acid (sodium hydroxide) which presented activity at 4 ppm. The anacardic acid's lead content was above the limits accepted by the United States standards.

  6. The life cycle of Zygocotyle lunata (Trematoda, Paramphistomoidea in the subtropical region of South America El ciclo de vida de Zygocotyle lunata (Trematoda, Paramphistomoidea en la región subtropical de América del Sur

    Directory of Open Access Journals (Sweden)

    Margarita Ostrowski de Núñez

    2011-06-01

    Full Text Available The life cycle of the trematode Zygocotyle lunata (Diesing, 1836 is studied, beginning with cercariae from naturally infected Biomphalaria peregrina (d'Orbigny, 1835 and B. tenagophila (d'Orbigny, 1835 from Buenos Aires Province and Salta Province (Argentina, respectively. Adults were recovered from Gallus domesticus (Linnaeus, 1758 and Mus musculus (Linnaeus, 1758. Egg development lasted for 15-23 days at 23-24 C, and 10-12 days at 28-30 C; it was delayed after successive passages through mice, and ceased thereafter. In the snail, sporocysts, located beneath the mantle border, occurred up to 37 days post exposure (PE. Rediae invaded the entire snail body; developing cercarial bodies within rediae were recognized by the presence of a short tail, excretory canals, and eye-spot pigment. Cercariae emerged from snails as early as 20-26 days PE, encysting immediately on any substrate. These can be easily differentiated from those of Paramphistomum Fischoeder, 1901 spp. and Cotylophoron Stiles and Goldberger, 1910 spp., which have lateral excretory tubes forming a ring at the midlevel of the body and usually lack pharyngeal appendages. Metacercariae were infective for at least 6 months. Mature adults were observed 27-32 days PE in mice and 35 days PE in chicks. Biomphalaria tenagophila represents a new intermediate natural host record and Salta Province a new geographic area; Dendrocygna viduata (Linnaeus, 1766 and D. bicolor (Vieillot, 1816 from Venezuela are new host records for Z. lunata.El ciclo de vida del trematode Zygocotyle lunata (Diesing, 1836 (Paramphistomoidea: Zygocotylidae fue estudiado experimentalmente, comenzando con cercarias emergidas de Biomphalaria peregrina (d'Orbigny, 1835 y B. tenagophila (d'Orbigny, 1835 infectadas naturalmente, provenientes de las provincias de Buenos Aires y Salta (Argentina, respectivamente. Los adultos fueron obtenidos de Gallus domesticus (Linnaeus, 1758 y Mus musculus (Linnaeus, 1758. El desarrollo del

  7. Dicty_cDB: Contig-U10720-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ) BGBV-aae37f05.b1 Snail_EST_pSMART Biomphalaria gl... 38 0.004 2 ( FG612470 ) stem_S086_C06.SEQ Opium poppy... stem cDNA library P... 32 0.004 3 ( FG605739 ) stem_S001_F08.SEQ Opium poppy stem cDNA library P... 32 0.00...4 3 ( FG606058 ) stem_S005_E09.SEQ Opium poppy stem cDNA library P... 32 0.004 3 ( FG613261 ) stem_S096_C09.SEQ Opium... poppy stem cDNA library P... 32 0.004 3 ( FG611387 ) stem_S072_B09.SEQ Opium... poppy stem cDNA library P... 32 0.004 3 ( FG613260 ) stem_S096_C08.SEQ Opium poppy stem cDNA library P

  8. [Comparative study of schistosomiasis transmission (urinary and intestinal forms) at 10 sites in Burkina Faso (in sub-Saharan Africa)].

    Science.gov (United States)

    Zongo, D; Kabre, B G; Dayeri, D; Savadogo, B; Poda, J N

    2012-01-01

    Despite great progress in schistosomiasis control over the past decade in Burkina Faso, this disease remains a public health problem. This study analyzes parasitologic data from investigations of Schistosoma haematobium, S. mansoni, and mollusks. The prevalence rate of S. haematobium varies from 3.3% to 50.4%; that for S. mansoni (tested only in the western part of the country) from 3.3% to 39.1%. Prevalence rates are higher in school-aged boys than girls, but the reverse is true among adults. Studies of mussels showed the presence of Biomphalaria pfeifferi, Bulinus truncatus, Bulinus senegalensis and Bulinus globosus in these areas. Our results indicate that behavioral factors as well as the dynamics and the distribution of the intermediate mollusks play a major role in the persistence of the disease.

  9. [Parasitological profile of two forms of schistosomiasis (urinary and intestinal forms) at ten sites in Burkina Faso (Sub-Saharan Africa country)].

    Science.gov (United States)

    Zongo, Dramane; Kabre, B Gustave; Dayeri, Dianou; Savadogo, Boubacar; Poda, Jean-Noël

    2013-01-01

    In spite of great progress in schistosomiasis control during the last decade in Burkina Faso, this disease remains a public health concern in the country. Indeed, our study consisted of the analysis of parasitological data related to Schistosoma haematobium and Schistosoma mansoni and in malacological investigations. The prevalence rate of Schistosoma haematobium varies from 3.3% to 50.4% and from 3.3% to 39.1% for Schistosoma mansoni, but only in the western part of Burkina Faso. Schoolboys are more infested than girls, but the phenomenon is reversed in adults. Biomphalaria pfeifferi, Bulinus truncatus, Bulinus senegalensis and Bulinus globosus were collected during this study. Thus, the behavioral factors as well as the dynamics and the distribution of the intermediate mollusks play a major role in the persistence of the disease.

  10. Dicty_cDB: Contig-U05543-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ctyostelium discoideum slug cDNA, clone SSJ403. 476 e-130 1 ( GO123462 ) CAGA20969.fwd CAGA Alvinella pompej...ana Normalized... 50 1e-07 2 ( GO107945 ) CAFZ7778.fwd CAFZ Alvinella pompejana I...ncyte regu... 50 1e-07 2 ( GO123461 ) CAGA20969.rev CAGA Alvinella pompejana Normalized... 50 1e-07 2 ( GO10...7944 ) CAFZ7778.rev CAFZ Alvinella pompejana Incyte regu... 50 1e-07 2 ( GO162865 ) CAGA40243.rev CAGA Alvin...... 32 0.063 3 ( EV821460 ) BGBV-aae59d10.g1 Snail_EST_pSMART Biomphalaria gl... 32 0.070 3 ( GO162866 ) CAGA40243.fwd CAGA Alvin

  11. Cloning and Characterization of an Abalone (Haliotis discus hannai) Actin Gene

    Institute of Scientific and Technical Information of China (English)

    MA Hongming; XU Wei; MAI Kangsen; LIUFU Zhiguo; CHEN Hong

    2004-01-01

    An actin encoding gene was cloned by using RT-PCR, 3' RACE and 5' RACE from abalone Haliotis discus hannai. The full length of the gene is 1532 base pairs, which contains a long 3' untranslated region of 307 base pairs and 79 base pairs of 5' untranslated sequence. The open reading frame encodes 376 amino acid residues. Sequence comparison with those of human and other mollusks showed high conservation among species at amino acid level. The identities was 96%, 97% and 96% respectively compared with Aplysia californica, Biomphalaria glabrata and Homo sapience β-actin. It is also indicated that this actin is more similar to the human cytoplasmic actin(β-actin)than to human muscle actin.

  12. Hemozoin formation in Echinostoma trivolvis rediae.

    Science.gov (United States)

    Pisciotta, John M; Ponder, Elizabeth L; Fried, Bernard; Sullivan, David

    2005-09-01

    Rediae of the trematode Echinostoma trivolvis, from naturally infected Helisoma trivolvis snails, form a black pigment while inside the snail host. Here we examine the black pigment to show that the insolubility characteristics in detergent and weak base solution are identical to Plasmodium falciparum hemozoin. Laser desorption mass spectrometry of the purified pigment demonstrates the presence of heme. Examination of purified pigment under polarized light microscopy illuminates ordered birefringent crystals. Field emission in lens scanning electron microscopy reveals irregular ovoid crystals of 200-300 nm in diameter. The purified pigment crystals seeded extension of monomeric heme onto the crystal which by Fourier Transform Infrared analysis is beta-hematin. Rediae of a second echinostome parasite, Echinostoma caproni, from experimentally infected Biomphalaria glabrata, do not produce measurable or recoverable heme crystals. These observations are consistent with heme crystal formation by a hematophagous parasite within a non-vertebrate intermediate host.

  13. Types of trematodes infecting freshwater snails found in irrigation canals in the East Nile locality, Khartoum, Sudan

    DEFF Research Database (Denmark)

    Mohammed, Nidal A. I.; Madsen, Henry; Ahmed, Abdel Aziz A. R. M.

    2016-01-01

    Background: The planorbid freshwater snails of the two genera, Biomphalaria and Bulinus -have been vigorously studied due to the role they play as intermediate hosts of schistosomiasis. In Sudan specifically, most studies have focused on the chemical and ecological control of the two genera......, but few studies have looked at their biological control. This study explored the coexistence of other species of freshwater snails and the two genera along with their trematode infections in relation to a number of environmental factors in the East Nile locality, Khartoum state, Sudan. Methods: Freshwater...... snails from irrigation canals (abueshreens) were sampled monthly from January 2004 to December 2005. The snails were examined for trematode infections by cercarial emergence immediately after collection and then weekly for an additional four weeks to allow for the maturation of prepatent infections...

  14. Associations between trematode infections in cattle and freshwater snails in highland and lowland areas of Iringa Rural District, Tanzania.

    Science.gov (United States)

    Nzalawahe, Jahashi; Kassuku, Ayub A; Stothard, J Russell; Coles, Gerald C; Eisler, Mark C

    2015-09-01

    The epidemiology of trematode infections in cattle was investigated within highland and lowland areas of Iringa Rural District, in southern Tanzania. Fecal samples were collected from 450 cattle in 15 villages at altitudes ranging from 696 to 1800 m above the sea level. Freshwater snails were collected from selected water bodies and screened for emergence of cercariae. The infection rates in cattle were Fasciola gigantica 28·2%, paramphistomes 62·8% and Schistosoma bovis 4·8%. Notably, prevalence of trematode infections in cattle was much higher in highland (altitude > 1500 m) as compared with lowland (altitude snails collected included Lymnaea natalensis, Bulinus africanus, Bulinus tropicus, Bulinus forskali, Biomphalaria pfeifferi, Melanoides tuberculata and Bellamya constricta with a greater proportion of highland (75%) than lowland (36%) water bodies harbouring snails. Altitude is a major factor shaping the epidemiology of F. gigantica and paramphistomes infections in cattle in Iringa Rural District with greater emphasis upon control needed in highland areas.

  15. Identification of planorbids from Venezuela by polymerase chain reaction amplification and restriction fragment length polymorphism of internal transcriber spacer of the RNA ribosomal gene

    Directory of Open Access Journals (Sweden)

    Caldeira Roberta L

    2000-01-01

    Full Text Available Snails of the genus Biomphalaria from Venezuela were subjected to morphological assessment as well as polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP analysis. Morphological identification was carried out by comparison of characters of the shell and the male and female reproductive apparatus. The PCR-RFLP involved amplification of the internal spacer region ITS1 and ITS2 of the RNA ribosomal gene and subsequent digestion of this fragment by the restriction enzymes DdeI, MnlI, HaeIII and MspI. The planorbids were compared with snails of the same species and others reported from Venezuela and present in Brazil, Cuba and Mexico. All the enzymes showed a specific profile for each species, that of DdeI being the clearest. The snails were identified as B. glabrata, B. prona and B. kuhniana.

  16. Distribution of freshwater snails in the river Niger basin in Mali with special reference to the intermediate hosts of schistosomes

    DEFF Research Database (Denmark)

    Madsen, Henry; Coulibaly, Godefroy; Furu, Peter

    1987-01-01

    Snail surveys were carried out in various parts of Mali. All areas surveyed are part of the Niger basin being either affluents or irrigation schemes fed by this river. The snail species present varied greatly between areas. The following potential hosts of schistosomes were recorded: Biomphalaria...... pfeifferi, Bulinus truncatus, B. globosus, B. umbilicatus, B. forskalii and B. senegalensis. In the large irrigation schemes, i.e. 'Office du Niger' and Baguinéda, only B. pfeifferi and B. truncatus appear to be intermediate hosts. Snail distribution appeared to some extent to be focal and high snail...... densities appeared to be associated with human water contact activities, which apparently create favourable biotopes for the snails. This is probably due to an alteration of the vegetation and an increase of the trophic status of the site by contamination with food remnants and other debris. The larger...

  17. Schistosomiasis risk mapping in the state of Minas Gerais, Brazil, using a decision tree approach, remote sensing data and sociological indicators

    Directory of Open Access Journals (Sweden)

    Flávia T Martins-Bedê

    2010-07-01

    Full Text Available Schistosomiasis mansoni is not just a physical disease, but is related to social and behavioural factors as well. Snails of the Biomphalaria genus are an intermediate host for Schistosoma mansoni and infect humans through water. The objective of this study is to classify the risk of schistosomiasis in the state of Minas Gerais (MG. We focus on socioeconomic and demographic features, basic sanitation features, the presence of accumulated water bodies, dense vegetation in the summer and winter seasons and related terrain characteristics. We draw on the decision tree approach to infection risk modelling and mapping. The model robustness was properly verified. The main variables that were selected by the procedure included the terrain's water accumulation capacity, temperature extremes and the Human Development Index. In addition, the model was used to generate two maps, one that included risk classification for the entire of MG and another that included classification errors. The resulting map was 62.9% accurate.

  18. Modelling spatial distribution of snails transmitting parasitic worms with importance to human and animal health and analysis of distributional changes in relation to climate

    DEFF Research Database (Denmark)

    Pedersen, Ulrik Bo; Midzi, Nicholas; Mduluza, Takafira

    2014-01-01

    The environment, the on-going global climate change and the ecology of animal species determine the localisation of habitats and the geographical distribution of the various species in nature. The aim of this study was to explore the effects of such changes on snail species not only of interest...... to naturalists but also of importance to human and animal health. The spatial distribution of freshwater snail intermediate hosts involved in the transmission of schistosomiasis, fascioliasis and paramphistomiasis (i.e. Bulinus globosus, Biomphalaria pfeifferi and Lymnaea natalensis) were modelled by the use...... of a maximum entropy algorithm (Maxent). Two snail observation datasets from Zimbabwe, from 1988 and 2012, were compared in terms of geospatial distribution and potential distributional change over this 24-year period investigated. Climate data, from the two years were identified and used in a species...

  19. Anacardic acid: molluscicide in cashew nut shell liquid.

    Science.gov (United States)

    Sullivan, J T; Richards, C S; Lloyd, H A; Krishna, G

    1982-03-01

    The components of anacardic acid, (a mixture of 6-n-C (15) alkylsalicylic acids whose side chains vary in degrees of unsaturation) have been isolated by high pressure liquid chromatography from a crude extract of cashew nut shell, Anacardium occidentale, and tested for toxicity to fresh water snails, Biomphalaria glabrata. The triene component is the most toxic form (LC (50) 0.35 ppm), the diene and monoene components are less toxic (LC (50) 0.9 and 1.4 ppm), and the saturated component is relatively nontoxic (LC (50) > 5 ppm). Since decarboxylated anacardic acid (cardanol) and salicylic acid do not kill snails at concentrations up to 5 ppm, it appears that both, carboxyl group and unsaturated side chain are absolutely required for molluscicidal activity. The mechanism of toxicity of anacardic acid to snails is unknown.

  20. Relação entre a patogenicidade do Schistosoma mansoni em camundongos e a susceptibilidade do molusco vetor: III. Mortalidade, pesos corporal e das vísceras Relationship between the pathogenicity of Schistosoma mansoni in mice and the susceptibility of the vector mollusc: III. Mortality, body weight and viscera weights

    Directory of Open Access Journals (Sweden)

    Eliana Maria Zanotti-Magalhães

    1995-08-01

    Full Text Available Estudou-se a relação entre o desenvolvimento da hepatomegalia, da esplenomegalia, peso corporal e taxa de mortalidade em camundongos experimentalmente infectados por Schistosoma mansoni com o grau de susceptibilidade de Biomphalaria glahrata e B. tenagophila nas quais se desenvolveram as cercárias infectantes respectivamente, das linhagens BH e SJ. Foram utilizados como hospedeiro definitivo camundongos Swiss, SPF e como hospedeiros intermediários populações de moluscos selecionados geneticamente para o caráter susceptibilidade. Foram observados menores pesos corporais e das visceras em camundongos infectados com cercárias provenientes de moluscos que apresentaram elevado grau de susceptibilidade. A maior susceptibilidade dos moluscos à infecção pelo S. mansoni correspondeu a uma menor sobrevivência dos camundongos infectados. Os resultados fazem crer que a maior adaptação do parasita ao hospedeiro intermediário, traduzidos pelas taxas mais elevadas de susceptibilidade, pode levar a um comportamento diferente deste parasita no hospedeiro definitivo.The relationship between the development of hepatomegaly, splenomegaly, body weight and mortality rate and the degree of susceptibility of Biomphalaria glabrata and B. tenagophila at which infective cercariae developed was studied. The study utilized Swiss mice, SPF, as definitive hosts and populations of snails genetically selected for character susceptibility as intermediate hosts. Low body weight and smaller viscera were observed in infected mice with cercariae originating from snails that showed a high degree of susceptibility. The higher susceptibility of molluscs infected with S. mansoni corresponded to a lower survival of the infected mice. These results lead to the conclusion that the higher degree of adaptation of the parasite to its intermediate hosts, evidenced by the high indexes of susceptibility, leads to different behaviour on the part of this parasite in its definitive

  1. Composição e sazonalidade dos moluscos do alto rio Paraná, Brasil, e sua potencialidade como hospedeiros intermediários de digenéticos - DOI: 10.4025/actascibiolsci.v30i3.5018 Composition and seasonality of mollusks from the upper Paraná river, Brazil, and their potentiality as intermediate hosts for digeneans - DOI: 10.4025/actascibiolsci.v30i3.5018

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    Gilberto Cezar Pavanelli

    2008-10-01

    Full Text Available Este trabalho analisa a composição e a sazonalidade das espécies de moluscos potenciais hospedeiros intermediários de trematódeos digenéticos, bem como fornece informações a respeito das possíveis infecções por diplostomídeos nesta comunidade, em ambientes lênticos da planície de inundação do alto rio Paraná. Foram coletadas e analisadas dez espécies de moluscos, e houve nítida sazonalidade na densidade e abundância dos moluscos, correlacionada significativamente com a temperatura da água. Os maiores valores observados foram entre os meses de novembro de 2002 a fevereiro de 2003. Apenas Biomphalaria peregrina caracterizou-se como hospedeiro para Diplostomidae, pois nesta espécie foram encontradas 32 cercárias de Hysteromorpha triloba em março de 2003.This study analyzes the composition and seasonality of mollusk species as potential intermediate hosts for digenean trematodes, and also supplies information regarding the possible infections by diplostomidae in that community, in lentic environments of the upper Paraná river floodplain. Ten species of mollusks were collected and analyzed, with noticeable seasonality in the density and abundance of mollusks, significantly correlated with water temperature. The highest values observed were in the period between November 2002 and February 2003. Only Biomphalaria peregrina was characterized as a host for diplostomidae, given that 32 cercariae of Hysteromorpha triloba were found in this species in March 2003.

  2. Ensaios preliminares em laboratório para verificar a ação moluscicida de algumas espécies da flora brasileira Preliminary laboratory tests of the molluscicide activity of some species of Brazilian flora

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    Nelymar Martineli Mendes

    1984-10-01

    Full Text Available Estudou-se em laboratório a atividade moluscicida de 68 extratos de 23 plantas brasileiras. As soluções em água desclorada dos extratos hexânicos e etanólico, nas concentrações de 1, 10 e 100 ppm, foram testadas sobre caramujos adultos e desovas de Biomphalaria glabrata, criados em laboratório. As plantas que demonstraram ação moluscicida na concentração de 100 ppm foram: Arthemisia verlotorum Lamotte, Caesalpinia peltophoroides Benth, Cassia rugosa G.Don., Eclipta alba Hassk, Euphorbia pulcherrima Willd, Euphorbia splendens Bojer, Joannesia princeps Vell, Leonorus sibiricus L.,Macrosiphonia guaranitica Muell,Nerium oleander L., Palicourea nicotianaefolia Cham, e Schlech., Panicum maximum M., Rumex crispus L., Ruta graveolens L., e Stryphnodendron barbatiman M.The molluscicide activity of sixty-eight extracts from twenty-three Brazilian plants was studied in the laboratory. The solutions, in dechlorinated water, of hexanic and ethylic extracts at 1, 10 and 100 ppm concentrations, were tested on adult snails and egg masses of Biomphalaria glabrata, reared in the laboratory. The plants with molluscicide activity on adult snails and/or egg masses at 100 ppm concentration were: Arthemisia verlotorum Lamotte, Caesalpinia peltophoroides Benth, Cassia rugosa G. Don, Eclipta alba Hassk, Euphorbia pulcherrima Willd, Euphorbia splendens Bojer, Joannesia princeps Vell, Leonorus sibiricus L., Macrosiphonia guaranitica Muell, Nerium oleander L., Palicourea nicotianaefolia Cham. and Schlech., Panicum maximum M., Rumex crispus L., Ruta graveolens L. and Stryphnodendron barbatiman M.

  3. Verificação da resposta de miracídios de Schistosoma mansoni a substâncias provenientes de moluscos planorbídeos: pesquisa de substâncias quimiotáxicas Response of Schistosoma mansoni miracidia to snail substance: research on chemiotaxic substances

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    Beatriz de Camargo Brasio

    1985-04-01

    Full Text Available Foi testada a atividade miraxonal da água de condicionamento (SCW e da hemolinfa de Biomphalaria glabrata e de B. tenagophila frente a miracídios de Schistosoma mansoni das linhagens BH e SJ. Foram pesquisados e isolados alguns componentes de SCW. Com os componentes isolados de SCW e com a hemolinfa foram preparados blocos de ágar. Esses blocos, assim preparados, foram colocados frente a miracídios de S. mansoni para avaliação da atividade miraxonal. Foram detectadas diferenças entre a ação miraxonal da hemolinfa e das substâncias isoladas de SCW. Observaram-se diferenças significativas entre os efeitos miraxonais das duas espécies de moluscos pesquisados frente a miracídios das linhagens BH e SJ.Several substances isolated from SCW (snail conditioned water and from snail hemolymph were tested for a possible chemiotaxic effect on Schistosoma mansoni miracidia. Two strains of miracidia were considered (SJ and BH. Agar plates prepared with one of the substances were exposed to sixty miracidia for five minutes. The number of contacts and contacts with return were counted. Ten replications were made. Eight types (and four sub types of agar plates were prepared: normal water (control, SCW (Biomphalaria glabrata and B. tenagophila, hemolymph (B. glabrata and B. tenagophila and amonia, calcium, magnesium, sodium and potassium. Log-linear models were fitted to the data to study the proportions of attraction to each substance and to compare them. Any possible differences in proportions of attraction between the two S. mansoni strains were tested.

  4. The Use of DNA Barcoding on Recently Diverged Species in the Genus Gentiana (Gentianaceae in China.

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    Juan Liu

    Full Text Available DNA barcoding of plants poses particular challenges, especially in differentiating, recently diverged taxa. The genus Gentiana (Gentianaceae is a species-rich plant group which rapidly radiated in the Himalaya-Hengduan Mountains in China. In this study, we tested the core plant barcode (rbcL + matK and three promising complementary barcodes (trnH-psbA, ITS and ITS2 in 30 Gentiana species across 6 sections using three methods (the genetic distance-based method, Best Close Match and tree-based method. rbcL had the highest PCR efficiency and sequencing success (100%, while the lowest sequence recoverability was from ITS (68.35%. The presence of indels and inversions in trnH-psbA in Gentiana led to difficulties in sequence alignment. When using a single region for analysis, ITS exhibited the highest discriminatory power (60%-74.42%. Of the combinations, matK + ITS provided the highest discrimination success (71.43%-88.24% and is recommended as the DNA barcode for the genus Gentiana. DNA barcoding proved effective in assigning most species to sections, though it performed poorly in some closely related species in sect. Cruciata because of hybridization events. Our analysis suggests that the status of G. pseudosquarrosa needs to be studied further. The utility of DNA barcoding was also verified in authenticating 'Qin-Jiao' Gentiana medicinal plants (G. macrophylla, G. crassicaulis, G. straminea, and G. dahurica, which can help ensure safe and correct usage of these well-known Chinese traditional medicinal herbs.

  5. The Use of DNA Barcoding on Recently Diverged Species in the Genus Gentiana (Gentianaceae) in China.

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    Liu, Juan; Yan, Hai-Fei; Ge, Xue-Jun

    2016-01-01

    DNA barcoding of plants poses particular challenges, especially in differentiating, recently diverged taxa. The genus Gentiana (Gentianaceae) is a species-rich plant group which rapidly radiated in the Himalaya-Hengduan Mountains in China. In this study, we tested the core plant barcode (rbcL + matK) and three promising complementary barcodes (trnH-psbA, ITS and ITS2) in 30 Gentiana species across 6 sections using three methods (the genetic distance-based method, Best Close Match and tree-based method). rbcL had the highest PCR efficiency and sequencing success (100%), while the lowest sequence recoverability was from ITS (68.35%). The presence of indels and inversions in trnH-psbA in Gentiana led to difficulties in sequence alignment. When using a single region for analysis, ITS exhibited the highest discriminatory power (60%-74.42%). Of the combinations, matK + ITS provided the highest discrimination success (71.43%-88.24%) and is recommended as the DNA barcode for the genus Gentiana. DNA barcoding proved effective in assigning most species to sections, though it performed poorly in some closely related species in sect. Cruciata because of hybridization events. Our analysis suggests that the status of G. pseudosquarrosa needs to be studied further. The utility of DNA barcoding was also verified in authenticating 'Qin-Jiao' Gentiana medicinal plants (G. macrophylla, G. crassicaulis, G. straminea, and G. dahurica), which can help ensure safe and correct usage of these well-known Chinese traditional medicinal herbs.

  6. THE ORIENTATION OF CaCO3 ARAGONITE CRYSTALS FROM SEVERAL ORGANISMS%几种生物CaCO3霰石结晶的取向性

    Institute of Scientific and Technical Information of China (English)

    蒋新农; 李敬之; 徐学红

    2001-01-01

    The CaCO3 crystals are widely distributed in organisms. Thecalcite, aragonite and vaterite are the main crystal polymorphisms of CaCO3. In this paper, CaCO3 crystals were obtained from the nacreous layers of Hyriopsis cumingii Lea and Pinctada martensii Dunker, the internal shell of a cuttlefish and the otolith of Pseudosciaena crocea. X-ray diffraction measurement was used to analyze the crystal orientation of CaCO3 crystals: The results showed that each kind of natural CaCO3 crystal has an orientation on specific plane. In detail, the crystal orientations of the nacreous layers are higher than the internal shell, and the orientation of the otolith is the lowest. Except the nacreous layers of Pinctada martensii, whose highest peak is on the crystal plane (312), all the other three natural samples have the highest peak on the crystal plane (012). As to ground CaCO3 crystals, the differences between their corresponding d values are very small, so each ground sample has the CaCO3 aragonite structure characterized by the JCPDS card (5-0453).%CaCO3结晶广泛分布于生物界,其主要结晶形式为方解石、霰石及球霰石。用X-射线衍射法对三角帆蚌及合浦珍珠母贝的珍珠层、墨鱼骨和大黄鱼耳石的CaCO3结晶进行测定,发现各样品均有一定取向性,以三角帆蚌和合浦珍珠母贝珍珠层的取向性为最强,墨鱼骨的取向性次之,大黄鱼耳石的取向性最小,以上材料粉末样的衍射分析表明,各样品对应d值间差异极小,均为X射线衍射卡(5-0453)所表征的CaCO3霰石结构。

  7. Distribución del género Diplodon (Mollusca: Bivalvia: Hyriidae en territorio Argentino mediante el uso de Colecciones Biológicas

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    Santiago Hernán Torres

    2013-10-01

    Full Text Available Los bivalvos nacaríferos dulciacuícolas (“náyades”, son especies infaunales, endémicas de la RegiónNeotropical, pertenecientes a las familias Hyriidae (Swaison, 1840 y Etheriidae (Swaison, 1840. La alteración del ambiente y la competencia con especies invasoras como Corbicula fluminea (Müller, 1774 y Limnoperna fortunei (Dunker, 1857, impactan sobre las poblaciones naturales. En esta comunicación, se presenta el inicio de un Proyecto de investigación sobre la distribución geográfica de las especies del género Diplodon en la Argentina. Estas especies son un componente importante de la infauna de los cuerpos lóticos y lénticos, viviendo en fondos limosos, limo-arenosos, excepcionalmente en sustratos duros, con un régimen nutricio filtrador, teniendo un papel importante como recicladores de materia orgánica. Conocer la distribución de los bivalvos pertenecientes al género Diplodon en el territorio Argentino permitirá el reconocimiento de potenciales áreas prioritarias para su conservación. Sobre la base de la bibliografía disponible y los ejemplares de las especies del genero Diplodon depositados en la Colección Malacológica del Museo de La Plata (FCNyM-UNLP, se confeccionó una matriz de datos que incluye la identificación del ejemplar, la colección en que se encuentra depositado, el número de catálogo, la localidad y la fecha de colecta. Cada localidad fue ubicada mediante el uso de cartas geográficas de Argentina y revisiones bibliográficas en imágenes satelitales de GoogleEarth, asignando las coordenadas para cada punto. Como resultado del trabajo se obtiene la distribución de estas especies nativas y se discute el grado de solapamiento con las dos especies de bivalvos invasores y el impacto de actividades humanas. 

  8. Genomics, molecular imaging, bioinformatics, and bio-nano-info integration are synergistic components of translational medicine and personalized healthcare research.

    Science.gov (United States)

    Yang, Jack Y; Yang, Mary Qu; Arabnia, Hamid R; Deng, Youping

    2008-09-16

    Supported by National Science Foundation (NSF), International Society of Intelligent Biological Medicine (ISIBM), International Journal of Computational Biology and Drug Design and International Journal of Functional Informatics and Personalized Medicine, IEEE 7th Bioinformatics and Bioengineering attracted more than 600 papers and 500 researchers and medical doctors. It was the only synergistic inter/multidisciplinary IEEE conference with 24 Keynote Lectures, 7 Tutorials, 5 Cutting-Edge Research Workshops and 32 Scientific Sessions including 11 Special Research Interest Sessions that were designed dynamically at Harvard in response to the current research trends and advances. The committee was very grateful for the IEEE Plenary Keynote Lectures given by: Dr. A. Keith Dunker (Indiana), Dr. Jun Liu (Harvard), Dr. Brian Athey (Michigan), Dr. Mark Borodovsky (Georgia Tech and President of ISIBM), Dr. Hamid Arabnia (Georgia and Vice-President of ISIBM), Dr. Ruzena Bajcsy (Berkeley and Member of United States National Academy of Engineering and Member of United States Institute of Medicine of the National Academies), Dr. Mary Yang (United States National Institutes of Health and Oak Ridge, DOE), Dr. Chih-Ming Ho (UCLA and Member of United States National Academy of Engineering and Academician of Academia Sinica), Dr. Andy Baxevanis (United States National Institutes of Health), Dr. Arif Ghafoor (Purdue), Dr. John Quackenbush (Harvard), Dr. Eric Jakobsson (UIUC), Dr. Vladimir Uversky (Indiana), Dr. Laura Elnitski (United States National Institutes of Health) and other world-class scientific leaders. The Harvard meeting was a large academic event 100% full-sponsored by IEEE financially and academically. After a rigorous peer-review process, the committee selected 27 high-quality research papers from 600 submissions. The committee is grateful for contributions from keynote speakers Dr. Russ Altman (IEEE BIBM conference keynote lecturer on combining simulation and machine

  9. Biological and environmental factors associated with risk of schistosomiasis mansoni transmission in Porto de Galinhas, Pernambuco State, Brazil Factores biológicos y ambientales asociados al riesgo de transmisión de la esquistosomiasis mansoni en la localidad de Porto de Galinhas, Pernambuco, Brasil Fatores biológicos e ambientais associados ao risco de transmissão da esquistossomose mansoni na localidade de Porto de Galinhas, Pernambuco, Brasil

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    Onicio Batista Leal Neto

    2013-02-01

    Full Text Available Schistosomiasis has expanded to the coast of Pernambuco State, Brazil, where there are frequent reports of Biomphalaria glabrata snails and human cases of the disease. This study analyzes factors related to schistosomiasis transmission risk in Porto de Galinhas. A one-year malacological survey was conducted to identify biological, abiotic, and environmental factors related to the host snail breeding sites. Data analysis used Excel 2010, GTM Pro, and ArcGis 10. A total of 11,012 B. glabrata snails were captured in 36 breeding sites, and 11 schistosomiasis transmission foci were identified. A negative correlation was found between breeding site temperature and snail density and infection rate, and a positive correlation with pH and salinity. The rainy season showed a positive correlation with snail density and infection rate. The study emphasizes the factors involved in the maintenance of schistosomiasis breeding sites, in light of persistence of this disease in Porto de Galinhas for more than 10 years.La esquistosomiasis se expande hacia el litoral de Pernambuco, Brasil, donde han sido frecuentes los registros de caracoles Biomphalaria glabrata y casos humanos de la enfermedad. Este estudio presenta factores relacionados con el riesgo de transmisión de la esquistosomiasis en la localidad Porto de Galinhas. Durante un año se llevó a cabo una investigación malacológica para identificar factores biológicos, abióticos y ambientales, relacionados con los criaderos de los moluscos huéspedes. Para el análisis de los datos se utilizaron los softwares Excel 2010, GTM Pro y ArcGis 10. Se recogieron 11.012 caracoles B. glabrata en los 36 criaderos identificados, siendo diagnosticados 11 focos de transmisión de la esquistosomiasis. Se verificó la correlación negativa entre la temperatura de los criaderos, densidad y tasa de infección de los caracoles, y la correlación positiva entre el pH y salinidad. El período de lluvia presentó una

  10. Assessment of toxicity and genotoxicity of the reactive azo dyes Remazol Black B and Remazol Orange 3R and effectiveness of electron beam irradiation in the reduction of color and toxic effects; Avaliacao da toxicidade e genotoxicidade dos corantes azo reativos Remazol Preto B e Remazol Alaranjado 3R e da eficacia da radiacao com feixe de eletrons na reducao da cor e efeitos toxicos

    Energy Technology Data Exchange (ETDEWEB)

    Pinheiro, Alessandro de Sa

    2011-07-01

    The textile industries play an important role in national and global economy. But, their activities are considered potentially polluting. The use of large volumes of water and the production of colored wastewater with high organic matter are among the main issues raised, especially during the stage of dyeing and washing of the textile process. The reactive azo dyes are the main colors used in the industry for dyeing of cotton in Brazil and worldwide. Because of its low setting and variations in the fiber production process, about 30% of the initial concentration used in the dyeing baths are lost and will compose the final effluent. These compounds have a low biodegradability, are highly soluble in water and therefore are not completely removed by conventional biological processes. In addition, other processes do not promote degradation but the transference to solid environment. The dyes discarded without treatment in the water body can cause aesthetic modifications, alter photosynthesis and gas solubility, as well as being toxic and genotoxic. The main objectives of this study were to evaluate the toxicity and genotoxicity of two reactive azo dyes (Remazol Black B - RPB and Remazol Orange 3R - R3AR) and the percentage of color and toxicity reduction after the use of electron beam radiation. The acute toxicity assays performed with Vibrio fischeri, Daphnia similis and Biomphalaria glabrata showed different response patterns for dyes. The different chemical forms of dyes were slightly toxic to Vibrio fischeri and only the RPB dye (vinylsulphone) was toxic (EC50{sub 15min} = 6,23 mg L-1). In tests with Daphnia similis, the dye RPB was slightly toxic in its pattern form, sulphatoethylsulphone, (CE50{sub 48h} = 91,25 mg L{sup -1}) and showed no toxicity in other chemical forms. However, the RA3R dye was toxic to the dafnids and the vinylsulphone form very toxic (EC50{sub 48h} = 0,54 mg L-1). No toxicity was observed in Biomphalaria glabrata assays. Chronic toxicity was

  11. Ocorrência de linhagens humana e silvestre de Schistosoma mansoni, na pré-amazônia: I - estudo em moluscos Occurrence of wild and human strains of Schistosoma mansoni in lower Amazonia: I - study in moluscs

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    Othon de Carvalho Bastos

    1982-10-01

    Full Text Available Foram isoladas na região da Baixada Maranhense (Brasil, linhagens humana (H e silvestre(S de Schistosoma mansoni a partir de miracídios eclodidos de ovos encontrados em fezes de doentes humanos autóctones da Região e de fígados de roedores silvestres naturalmente infectados. Biomphalaria glabrata, descentes de caramujos coletados no campo, foram expostos, isoladamente, aos miracídios H e S, mantidos isolados em moluscário e observados durante 100 dias. Moluscos normais foram mantidos nas mesmas condições de ambiente em que foram submetidos os infectados e tomados como controle da experiência. Foram anotados os indices de infecção dos moluscos, as datas da eliminação de cercárias, quantidade de larvas eliminadas e mortalidade dos moluscos. Os dados sugeriram melhor adaptação do esquistossomo da linhagem H à B. glabrata. A linhagem S, por sua vez, foi três vezes mais virulenta do que a linhagem H. Estes dados foram comparados com os encontrados na literatura especializada e verificado diversidades nos comportamentos parasitológicos das linhagens em estudo, quando comparados com os encontrados nas linhagens H e S oriundas do Vale do Rio Paraíba do Sul, no Estado de São Paulo (Brasil.The wild (W and human (H strains of Schistosoma mansoni were isolated in the Lowland Region of the Maranhão State (Brazil. The snail progenies from Biomphalaria glabrata collected from that region were exposed to the W miracidia, obtained from livers of wild rodents, and H miracidia from eggs in human stools. A control gruop of normal snails was kept in the same conditions as the infected one. The date of the elimination of cercariae, the quantity of eliminated larvae, the infection index of the moluscs and the mortality rate of the snails were recorded. These data suggested better adaptation of the H strain to B. glabrata. The W strain presented three times more virulence to snails than the H strain. These results were compared with published

  12. Schistosomiasis mansoni in an area of low transmission: II. Risk factors for infection Esquistossomose mansônica em área de baixa transmissão: II. Fatores de risco para infecção

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    Oswaldo Marçal Júnior

    1993-08-01

    Full Text Available Risk factors for Schistosoma mansoni infection were identified using a 1:1 matched case-control design. The work was conducted in the municipality of Pedro de Toledo, São Paulo State, Brazil, an area where the snail host is Biomphalaria tenagophila. Information on water contact patterns, knowledge, attitudes and pratices (kap, socioeconomic and sanitary conditions were obtained by mean of questionnaires. The crude odds ratio estimates and the adjusted odds ratio estimates using the logistic regression model are presented. Most of the examined individuals admitted recent water contacts (90.6% of the cases. The most frequent reason for contact was swimming, playing and fishing and the preferential site of contact was the river. According to the logistic regression technique, the main risk factors for infection were: a water contact through swimming, playing and fishing; b fording; c bad hygiene. We concluded that recreational activities are the main reasons for schistosomiasis transmission in Pedro de Toledo and leisure alternatives should be offered to the local population.A partir de um estudo de caso-controle por pareamento (1:1 foram determinados os fatores de risco para infecção por Schistosoma mansoni. O trabalho foi desenvolvido no município de Pedro de Toledo, São Paulo, Brasil, área onde Biomphalaria tenagophila é o hospedeiro intermediário. Por meio de questionários foram obtidas informações sobre o padrão de contato com águas naturais; percepção da doença e condições sanitárias e socio-econômicas. Os fatores de risco foram estimados individualmente e através de modelo logístico. A maioria dos pesquisados admitiu contatos recentes com águas naturais (90,6% dos casos. O motivo mais freqüente para estes contatos foi nadar, brincar e pescar. O rio representou o principal local de contato com águas naturais. De acordo com a técnica de regressão logística, os principais fatores de risco foram: a contato com

  13. Genetic variation between susceptible and non-susceptible snails to Schistosoma infection using random amplified polymorphic DNA analysis (RAPDs Variação genética entre moluscos susceptíveis e não susceptíveis à infecção pelo Schistosoma através da análise do DNA polimórfico amplificado aleatóriamente (RAPDs

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    Abdel-Hamid Zaki ABDEL-HAMID

    1999-09-01

    Full Text Available Susceptibility of snails to infection by certain trematodes and their suitability as hosts for continued development has been a bewildering problem in host-parasite relationships. The present work emphasizes our interest in snail genetics to determine what genes or gene products are specifically responsible for susceptibility of snails to infection. High molecular weight DNA was extracted from both susceptible and non-susceptible snails within the same species Biomphalaria tenagophila. RAPD was undertaken to distinguish between the two types of snails. Random primers (10 mers were used to amplify the extracted DNA by the polymerase chain reaction (PCR followed by polyacrylamide gel electrophoresis (PAGE and silver staining. The results suggest that RAPD represents an efficient means of genome comparison, since many molecular markers were detected as genetic variations between susceptible and non-susceptible snails.A susceptibilidade de moluscos à infecção por certos trematódeos e a sua capacidade como hospedeiro para o contínuo desenvolvimento é o problema mais deslumbrante nas relações parasita hospedeiro. O presente trabalho, focaliza nosso interesse na genética dos moluscos para determinar quais genes ou produtos gênicos são especificamente responsáveis pela susceptibilidade do molusco à infecção. DNA de alto peso molecular, foi extraído de ambos moluscos susceptíveis e não susceptíveis da espécie Biomphalaria tenagophila. Iniciadores aleatórios com 10 pares de bases foram usados na amplificação aleatória (RAPD de ambos os DNAs e análise por eletroforese em gel de poliacrilamida e coloração com prata. Os resultados mostram que a amplificação aleatória do DNA representa um eficiente caminho para a comparação dos genomas desde que marcadores moleculares foram detectados como variantes genéticos entre os moluscos susceptíveis e não susceptíveis.

  14. Comportamento da cepa LE de Schistosoma mansoni, após passagem em hospedeiro humano infectado acidentalmente

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    Neusa Araújo

    1986-12-01

    Full Text Available Uma auxiliar de laboratório infectou-se acidentalmente, com cercárias de Schistosoma mansoni, cepa LE, mantida rotineiramente em nossos laboratórios. Decorridos 5 meses, o exame parasitológico de fezes revelou 108 ovos/g . A pacientefoi tratada com oxamniquine, porém a infecção continuou ativa (6 ovos/g. Foi então obtido o isolado SSF mantido no modelo Biomphalaria glabrata - camundongo albino. Os resultados obtidos no estudo comparativo, entre o isolado SSF e a cepa LE, que lhe deu origem, mostraram que a duração do período pré-patente e o índice de infectividade em camundongos, bem como a resposta aos agentes esquistossomicidas (hycanthone, oxamniquine epraziquantel não apresentaram diferenças estatisticamente significativas. Por outro lado, o número de miracídios obtidos dos intestinos e fígados dos camundongos infectados foi o dobro com a cepa LE, quando comparados com aquele do isolado SSF. Também a variação do peso dos animais foi bastante diferente. Concluiu-se que apenas uma passagem pelo hospedeiro humano não mudou substancialmente as características da cepa estudada.A laboratory technician was accidentally infected with the LE strain of Schistosoma mansoni cercariae maintained in our laboratories. After 5 months infection parasitological examination revealed 108 eggs/g faeces. Althrough treated with oxamniquine, the infection still persisted (6 eggs/g of faeces. An isolate (SSF was obtained from that person and maintained in Biomphalaria glabrata - Swiss mouse by alternate passage. The experimental comparative results between the newly obtained SSF isolate and the original LE strain showed that the differences in pre-patent period, the mice infectivity level and the schistosomicidal response to hycanthone, oxamniquine and praziquantel was not statistically significant. On the other hand the number of miracidia recovered from intestines and livers of equally infected mice was twice as miich in the LE strain than

  15. Brine shrimp bioassay of some species of Solanum from Northestern Brazil Bioatividade em Artemia salina de várias espécies de Solanum do Nordeste Brasileiro

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    Tania Maria S. Silva

    2007-03-01

    Full Text Available The methanolic extracts of 13 Specieis of the genus Solanum (Solanaceae have been tested for bioactivity in Artemia salina. The extracts investigated were prepared from various parts (aerial parts, roots and fruits of S. asperum, S. capsicoides, S. palinacantum, S. paludosum, S. paniculatum, S. paraibanum, S. sisymbriifolium, S. crinitum, S. diamantinense, S. megalonyx, S. torvum, S. asterophorum and S. stipulaceum. The lethal concentrations were determined for the extracts and among thirteen plants tested, four appear to be inactive. The extracts of the fruits of S. asperum (LC50 = 420.5 µg/mL and S. paludosum (LC50 = 548.0 µg/mL, aerial parts of S. diamantinense (LC50 = 481.0 µg/mL and S. sisymbrifolium (LC50 = 382.7 µg/mL, and the roots of S. asperum (LC50 = 593.4 µg/mL and S. stipulaceum (LC50 = 823.1 µg/mL, all of which previously showed molluscicidal activity against Biomphalaria glabrata were also found to be active in the present study with brine shrimp.Os extratos metanólicos de 13 espécies de Solanum (Solanaceae foram testados para verifificação da bioatividade em Artemia salina. As espécies testadas (partes aéreas, raízes e frutos foram: S. asperum, S. capsicoides, S. palinacantum, S. paludosum, S. paniculatum, S. paraibanum, S. sisymbriifolium, S. crinitum, S. diamantinense, S. megalonyx, S. torvum, S. asterophorum e S. stipulaceum. Das treze espécies testadas, quatro foram inativas. Os extratos dos frutos de S. asperum (CL50 = 420,5 µg/mL e S. paludosum (CL50 = 548,0 µg/mL, partes aéreas de S. diamantinense (CL50 = 481,0 µg/mL e S. sisymbrifolium (CL50 = 382,7 µg/mL, e das raízes S. asperum (CL50 = 593,4 µg/mL e S. stipulaceum (CL50 = 823,1 µg/mL que mostraram atividade moluscicida contra Biomphalaria glabrata também mostraram atividade tóxica em Artemia salina.

  16. Interaction of gamma radiation on the functionality of the molluscicidal extract of Anacardium occidentale Linn

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Gustavo Henrique Farias dos [Grupo de Estudos em Radioprotecao e Radioecologia (GERAR) . Departamento de Energia Nuclear. Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Silva, Edvane Borges da [Centro Academico de Vitoria. Universidade Federal de Pernambuco (UFPE), Vitoria de Santo Antao, PE (Brazil); Amorim, Elba Lucia C.; Peixoto Sobrinho, Tadeu J.S., E-mail: elba@ufpe.br [Departamento de Ciencias Farmaceuticas. Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Melo, Ana Maria Mendonca de Albuquerque; Lima, Claudia Sampaio de Andrade [Departamento de Biofisica e Radiobiologia. Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2011-07-01

    Biological control of Biomphalaria glabrata that is the intermediate host of Schistosoma mansoni, through molluscicides has been an alternative against schistosomiasis. Many studies have been developed to obtain molluscicide products, from plants. Anacardium occidentale L. (cashew), a plant rich in phenolic compounds shows molluscicidal activity in earlier assays. However there is an interest of enhancing the action of bioactive substances in order to use it in small concentrations, reducing costs in their utilization. This study were conducted using ethanolic extracts of bark and leaves of A. occidentale, before and after exposure to gamma radiation from {sup 60}Co, checking their secondary metabolites, their biological activity against Biomphalaria glabrata and environmental toxicity. The extracts of A. occidentale were obtained by cold maceration in 70% ethanol, filtered, dried and divided into two experimental groups: control (0 kGy) and irradiated at a dose of 10 kGy. The quantification of metabolites was performed in six replicates for the determination of total phenols by Folin-Ciocalteau method and tannins, the precipitation of casein. Tests for biological control of embryos and adults of B. glabrata snails and assessment of environmental toxicity (using Artemia salina larvae) were performed in triplicate, following a period of 24 hours of exposure to extracts at a concentration of 100 mg/L and its respective controls. Data were expressed as percentages of means and standard deviations. The results showed that the gamma radiation from {sup 60}Co resulted in leaf extracts, increased levels of total phenols and tannins, which enhanced the lethality for embryos and adults of B. glabrata. There was a reduction of the toxicity of leaf extracts after irradiation in the Artemia salina. Since in extracts of bark, gamma radiation did not alter the levels of total phenols and tannins, however, it was noted potentiation of lethality of adult snails of B. glabrata. The

  17. Esquistossomose na área hiperendêmica de Taquarendi: I Infecção pelo Schistosoma mansoni e formas graves Schistosomiasis in hyperendemic area of Taquarendi: I- Schistosoma mansoni infection and severe clinical forms

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    José Carlos Bina

    2003-04-01

    Full Text Available A localidade de Taquarendi (Bahia está situada em zona de caatinga, porém com pequena faixa de terra irrigada, onde se encontram caramujos Biomphalaria glabrata. Dos 1.532 habitantes, 1.105 (72,1% submeteram-se ao exame clínico e, destes, 1.058 (95,7% fizeram exame parasitológico de fezes. A prevalência da esquistossomose foi de 73,1%, sendo que 16,2% destes eliminavam mais de 1.000 ovos por grama de fezes. O exame clínico mostrou que o lobo esquerdo do f��gado estava aumentado e/ou endurecido em 54% dos pacientes e o baço foi palpado em 21,8%. Foram classificados como hepatosplênicas 9,8% dos examinados e como portadores da forma hepatintestinal avançada 3,7%. Houve relação direta entre estas formas clínicas da doença e a intensidade da carga parasitária acima de 1.000 ovos de S. mansoni por grama de fezes.The study was carried out in Taquarendi (Bahia, a caatinga zone with a small irrigated strip of land, where Biomphalaria glabrata snails are found. From the 1,532 inhabitants, 1,105 (72.1% were submitted to clinical examination and 1058 out of them (95.7% made stool examinations. Prevalence of schistosomiasis was 73.1% and 16.2% of these patients eliminated more than 1,000 eggs per gram of stool. By clinical examination, the size and the consistency of the left liver lobe were increased in 54% of the individuals and the spleen was palpable in 21.8%. The diagnosis of hepatosplenomegaly and of the advanced hepatointestinal clinical form was made, respectively, in 9.8% and 3.7%. A direct relationship between such clinical forms of the disease and the worm load over 1.000 S. mansoni eggs/g of fezes was found.

  18. Molluscicidal and Mosquitocidal activities of the essential oils of Thymus capitatus Hoff. et Link. and Marrubium vulgare L.

    Science.gov (United States)

    Salama, Maha M; Taher, Eman E; El-Bahy, Mohamed M

    2012-01-01

    Steam distillation of essential oils of aerial parts of Thymus capitatus and Marrubium vulgare L. collected at North cost of Egypt yielded 0.5% and 0.2%, respectively. Results of Gas chromatography-mass spectrometry analyses of the two samples identified 96.27% and 90.19% of the total oil composition for T. capitatus and M. vulgare, respectively. The two oil samples appeared dominated by the oxygenated constituents (88.22% for T. capitatus and 57.50% for M. vulgare), composed of phenols, mainly carvacrol (32.98%) and thymol (32.82%) in essential oil of T. capitatus, and thymol (34.55%) in essential oil of M. vulgare. It was evaluated the molluscicidal activity of T. capitatus and M. vulgare essential oils on adult and eggs of Biomphalaria alexandrina as well as their mosquitocidal activity on Culex pipiens. The LC50 and LC90 of T. capitatus essential oil against adult snails was 200 and 400 ppm/3hrs, respectively, while for M. vulgare it was 50 and 100 ppm/3hrs, respectively. Moreover, M. vulgare showed LC100 ovicidal activity at 200 ppm/24 hrs while T. capitatus oil showed no ovicidal activity. It was verified mosquitocidal activity, with LC50 and LC90 of 100 and 200 ppm/12hrs respectively for larvae, and 200 and 400 ppm/12hrs respectively for pupae of C. pipiens.

  19. Rural tourism: a risk factor for schistosomiasis transmission in Brazil

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    Martin Johannes Enk

    2010-07-01

    Full Text Available This paper reports an outbreak of acute schistosomiasis among 38 tourists who rented a country house in the district of Igarapé, the metropolitan region of Belo Horizonte, Brazil, during a holiday period in 2006. A total number of 32 individuals were positive for Schistosoma mansoni. Results of stool examinations revealed individual S. mansoni egg counts per gram of faeces (epg ranging from 4-768 epg with a geometric mean egg count of 45. The most frequent clinical symptoms were abdominal pain (78.1%, headache (75%, fever (65.6%, dry cough (65.2% and both diarrhoea and asthenia (59.4%. A malacological survey of the area, where 22 specimens of Biomphalaria glabrata were collected, revealed three (13.6% specimens eliminating Schistosoma cercariae. This investigation re-confirms a recently described pattern of schistosomiasis infection, resulting in the acute form of the disease and connected to rural tourism, which contributes to the spread of the disease among the middle-class and into non-endemic areas. The lack of specific knowledge about acute schistosomiasis among health services causes an increased number of unnecessary diagnostic procedures and delays in accurate diagnosis and treatment, resulting in considerable discomfort for the patients.

  20. Immunolocalization of Schistosoma mansoni and Schistosoma haematobium antigens reacting with their Egyptian snail vectors.

    Science.gov (United States)

    El-Dafrawy, Shadia M; Mohamed, Amira H; Hammam, Olfat A; Rabia, Ibrahim

    2007-12-01

    The reaction of the haemolymph and the tissue of infected intermediate hosts, Biomphalaria alexandrina and Bulinus truncatus to Schistosoma mansoni and S. haematobium antigens were investigated using the indirect immunoperoxidase technique. A new technique, Agarose cell block was used in collection of haemolymph which helped in collecting plenty of well formed cells in comparison to the ordinary one using the cytospin. Collected haemolymph and prepared tissues of uninfected and infected B. alexandria and B. truncatus were fixed and then reacted with anti-S. mansoni and anti-S. haematobium IgG polyclonal antibodies. The haemolymph and tissue of infected B. alexandrina and B. truncatus gave a positive peroxidase reaction represented by a brown colour. In haemolymph, the positive peroxidase reaction was detected mainly in the cytoplasm of the amoebocytes. In the tissue, it was detected in epithelial cells lining the tubules, male cells in the lumen of the tubules and in female oogonia cells along the periphery of the tubules. The similarity in the strength and distribution of positive reaction in B. alexandrina and B. truncates was observed as compared to control. Thus, the immunoperoxidase technique proved to be an effective indicator for the schistosome-antigen in the snails.

  1. Schistosome/mollusk: genetic compatibility.

    Science.gov (United States)

    Oliveira, A L D; Da Silva, D; Zanotti-Magalhaes, E M; Abdel-Hamid, A Z; Ribeiro-Paes, J T

    2008-01-01

    Schistosomiasis remains one of the most prevalent parasitic infections and has significant economic and public health consequences in many developing countries. Economic development and improvement in standard of living in these countries are dependent on the elimination of this odious disease. For the control of Schistosomiasis, understanding the host/parasite association is important, since the host parasite relationship is often complex and since questions remain concerning the susceptibility of snails to infection by respective trematodes and their specificity and suitability as hosts for continued parasite development. Thus, the long term aim of this research is to learn more about the genetic basis of the snail/parasite relationship with the hope of finding novel ways to disrupt the transmission of this disease. In the current research, genetic variability among susceptible and resistant strains within and between Biomphalaria glabrata and B. tenagophila was investigated using RAPD-PCR. The results indicate great genetic variations within the two snail species using three different primers (intrapopulational variations), while specimens from the same snail species showed few individual differences between the susceptible and resistant strains (interpopulational variation).

  2. [Schistosomiasis in an ecotourism area in Minas Gerais State, Brazil].

    Science.gov (United States)

    Massara, Cristiano Lara; Amaral, Graciela Larissa; Caldeira, Roberta Lima; Drummond, Sandra Costa; Enk, Martin Johannes; Carvalho, Omar dos Santos

    2008-07-01

    This paper discusses schistosomiasis transmission in São José da Serra, a village with a population of 500 in the county of Jaboticatubas, Minas Gerais State, Brazil. The area receives thousands of visitors a year for ecotourism. The study was motivated by a case of acute schistosomiasis involving a couple that spent the 2007 Carnival (Mardi Gras) holiday in the area. Stool tests from 268 local residents (53.6% of the population) showed that 35 (13%) were positive for the infection. A comparison with a previous survey (2005) in the same location showed an increase in the schistosomiasis-positive rate from 9.6% to 12.5%, among the 56 individuals who participated in both surveys. A malacological survey of 65 Biomphalaria glabrata snails showed one specimen (1.5%) eliminating cercariae. In a similar survey in 2005, no positive snail specimens were found. The study indicates that active schistosomiasis transmission is occurring in the area, and that integrated educational programs are needed for both the local community and tourists.

  3. Comportamento da cepa LE de Schistosoma mansoni, após passagem em hospedeiro humano infectado acidentalmente

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    Neusa Araújo

    1986-12-01

    Full Text Available Uma auxiliar de laboratório infectou-se acidentalmente, com cercárias de Schistosoma mansoni, cepa LE, mantida rotineiramente em nossos laboratórios. Decorridos 5 meses, o exame parasitológico de fezes revelou 108 ovos/g . A pacientefoi tratada com oxamniquine, porém a infecção continuou ativa (6 ovos/g. Foi então obtido o isolado SSF mantido no modelo Biomphalaria glabrata - camundongo albino. Os resultados obtidos no estudo comparativo, entre o isolado SSF e a cepa LE, que lhe deu origem, mostraram que a duração do período pré-patente e o índice de infectividade em camundongos, bem como a resposta aos agentes esquistossomicidas (hycanthone, oxamniquine epraziquantel não apresentaram diferenças estatisticamente significativas. Por outro lado, o número de miracídios obtidos dos intestinos e fígados dos camundongos infectados foi o dobro com a cepa LE, quando comparados com aquele do isolado SSF. Também a variação do peso dos animais foi bastante diferente. Concluiu-se que apenas uma passagem pelo hospedeiro humano não mudou substancialmente as características da cepa estudada.

  4. Bioactivity of miltefosine against aquatic stages of Schistosoma mansoni, Schistosoma haematobium and their snail hosts, supported by scanning electron microscopy

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    El Bardicy Samia

    2011-05-01

    Full Text Available Abstract Background Miltefosine, which is the first oral drug licensed for the treatment of leishmaniasis, was recently reported to be a promising lead compound for the synthesis of novel antischistosomal derivatives with potent activity in vivo against different developmental stages of Schistosoma mansoni. In this paper an in vitro study was carried out to investigate whether it has a biocidal activity against the aquatic stages of Schistosoma mansoni and its snail intermediate host, Biomphalaria alexandrina , thus being also a molluscicide. Additionally, to see whether miltefosine can have a broad spectrum antischistosomal activity, a similar in vitro study was carried out on the adult stage of Schistosoma haematobium, the second major human species, its larval stages and snail intermediate host, Bulinus truncutes. This was checked by scanning electron microscopy. Results Miltefosine proved to have in vitro ovicidal, schistolarvicidal and lethal activity on adult worms of both Schistosoma species and has considerable molluscicidal activity on their snail hosts. Scanning electron microscopy revealed several morphological changes on the different stages of the parasite and on the soft body of the snail, which further strengthens the current evidence of miltefosine's activity. This is the first report of mollusicidal activity of miltefosine and its in vitro schistosomicidal activity against S.haematobium. Conclusions This study highlights miltefosine not only as a potential promising lead compound for the synthesis of novel broad spectrum schistosomicidal derivatives, but also for molluscicidals.

  5. Confirmed local endemicity and putative high transmission of Schistosoma mansoni in the Sesse Islands, Lake Victoria, Uganda

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    Kabatereine Narcis B

    2011-03-01

    Full Text Available Abstract The Sesse Islands, in the Ugandan portion of Lake Victoria, have long been considered a low transmission zone for intestinal schistosomiasis. Based on observations of high prevalence of Schistosoma mansoni infection in the northern-most islands of this archipelago, a follow-up survey was conducted to ascertain whether transmission was endemic to this island group, combining parasitological and malacological surveys. Prevalence of intestinal schistosomiasis was again observed to be high, as was intensity of infections which, combined with low reported incidence of treatment, suggests that chemotherapy-based control initiatives are not being maximally effective in this region as high levels of population movement between islands and districts are confounding. The local disease transmission was confirmed by the observations of high abundance of Biomphalaria, as well as field-caught snails shedding S. mansoni cercariae. DNA sequencing of 12 cercariae revealed common mitochondrial cox1 haplotypes, as well as, novel ones, consistent with the high genetic diversity of this parasite in Lake Victoria. Intestinal schistosomiasis is firmly endemic in parts of the Sesse Islands and more broadly, this island group provides an insight into the future challenges to be faced by the Ugandan National Control Programme in regularly reaching these rather remote, inaccessible and largely itinerant communities.

  6. Activity of Euphorbia splendens var. hislopii N.E.B. (Euphorbiaceae latex against Lymnaea columella (Say, 1817 (Pulmonata: Lymnaeidae, intermediate host of Fasciola hepatica, Linnaeus, 1758 (Trematoda: Fasciolidae. 2: limited field-testing

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    Vasconcellos Mauricio Carvalho de

    2003-01-01

    Full Text Available The molluscicidal evaluation of Euphorbia splendens var. hislopii (Crown of thorns against Lymnaea columella snails, intermediate host of Fasciola hepatica, in irrigation ditches of the Pisciculture Station at Universidade Federal Rural do Rio de Janeiro, was studied under limited field conditions. An aqueous solution of the latex at 5 mg/l was tested in two irrigation ditches (experimental and control ditches, after initial sampling of the snail population present. Twenty-four hours after application of the product, it was verified that 97.4% of free L. columella snails and 100% of snails of the same species captive in cages and used as sentinels at three points equidistant from the application site in the experimental ditch, died. For Biomphalaria tenagophila and Melanoides tuberculata snails, present in the experimental ditch, the mortality was 100%, for the species Pomacea spp. the mortality was 40%. No mortality was verified in the free mollusks, or in the sentinels in the ditch used as control. E. splendens var. hislopii latex is thus an efficient natural molluscicide, which may be used as an alternative control agent against L. columella.

  7. Effect of crude extract of Solanum xanthocarpum against snails and mosquito larvae.

    Science.gov (United States)

    Changbunjong, Tanasak; Wongwit, Waranya; Leemingsawat, Somjai; Tongtokit, Yuwadee; Deesin, Vanida

    2010-03-01

    The ethanolic crude extract from Solanum xanthocarpum was investigated for its molluscicidal activity against Biomphalaria glabrata, the snail vector of Schistosoma mansoni, and Indoplanorbis exustus, the snail vector of intestinal echinostomiasis and Schistosoma spindale, together with the larvicidal activity against the larvae of Aedes aegypti, mosquito vector of dengue hemorrhagic fever and Culex quinquefasciatus, the mosquito vector of urban bancroftian filariasis. The bioassays were carried out following the methods recommended by the World Health Organization. For molluscicidal activity, the LC50 against Bi. glabrata and I. exustus were reported at 163.85 and 198.00 mg/l while the LC90 were 219.33 and 236.80 mg/l, respectively. Regarding mosquito larvicidal activity, the LC50 against the larvae of Ae. aegypti and Cx. quinquefasciatus were 788.10 and 573.20 mg/l, while the LC90 were 1288.91 and 1066.93 mg/l, respectively. These results suggest a preparation of ingredients from this plant may be used as a biological larvicide for these vectors in the field.

  8. Saponins from Swartzia langsdorffii: biological activities

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    Magalhães Aderbal Farias

    2003-01-01

    Full Text Available The presence of saponins and the molluscicidal activity of the roots, leaves, seeds and fruits of Swartzia langsdorffii Raddi (Leguminosae against Biomphalaria glabrata adults and eggs were investigated. The roots, seeds and fruits were macerated in 95% ethanol. These extracts exerted a significant molluscicidal activity against B. glabrata, up to a dilution of 100 mg/l. Four mixtures (A2, B2, C and D of triterpenoid oleanane type saponins were chromatographically isolated from the seed and fruit extracts. Two known saponins (1 and 2 were identified as beta-D-glucopyranosyl-[alpha-L-rhamnopyranosyl-(1->3- beta-D-glucuronopyranosyl-(1->3]-3beta-hydroxyolean-12-ene-28 -oate, and beta-D-glucopyranosyl-(1->3-beta-D-glucuronopyranosyl-(1 ->3]-3beta-hydroxyolean-12-ene-28-oate, respectively. These two saponins were present in all the mixtures, together with other triterpenoid oleane type saponins, which were shown to be less polar, by reversed-phase HPLC. The saponin identifications were based on spectral evidence, including ¹H-¹H two-dimensional correlation spectroscopy, nuclear Overhauser and exchange spectroscopy, heteronuclear multiple quantum coherence, and heteronuclear multiple-bond connectivity experiments. The toxicity of S. langsdorffii saponins to non-target organisms was prescreened by the brine shrimp lethality test.

  9. Caracterización molecular de diferentes morfos de Melanoides tuberculata (Mollusca: Thiaridae mediante microsatélites

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    David P.

    2001-06-01

    Full Text Available M. tuberculataes un molusco asiático invasor de ecosistemas tropicales y subtropicales. En Amé-rica, su uso como control biológico ha sido probado en el desplazamiento de poblaciones deBiomphalaria spp. (Mollusca: Planorbidae, hospedadores intermediarios de Schistosoma mansoni(Trematoda: Digenea. A su vez, M. tuberculataes una especie que presenta gran plasticidad feno-típica, reconociéndose varias entidades morfológicas (morfos a lo largo de su rango de distribu-ción. Este trabajo pretende identificar la combinación de alelos microsatelitales característicos de10 morfos americanos. En este orden de ideas, se realizó una extracción de ADN con bufferValsecchi y baño María 90-95ºC (5-15’; se hizo una PCR utilizando primers específicos para M.tuberculata, y finalmente un análisis de secuencias microsatelitales con un secuenciador automá-tico.

  10. Hydrology and density feedbacks control the ecology of intermediate hosts of schistosomiasis across habitats in seasonal climates.

    Science.gov (United States)

    Perez-Saez, Javier; Mande, Theophile; Ceperley, Natalie; Bertuzzo, Enrico; Mari, Lorenzo; Gatto, Marino; Rinaldo, Andrea

    2016-06-07

    We report about field and theoretical studies on the ecology of the aquatic snails (Bulinus spp. and Biomphalaria pfeifferi) that serve as obligate intermediate hosts in the complex life cycle of the parasites causing human schistosomiasis. Snail abundance fosters disease transmission, and thus the dynamics of snail populations are critically important for schistosomiasis modeling and control. Here, we single out hydrological drivers and density dependence (or lack of it) of ecological growth rates of local snail populations by contrasting novel ecological and environmental data with various models of host demography. Specifically, we study various natural and man-made habitats across Burkina Faso's highly seasonal climatic zones. Demographic models are ranked through formal model comparison and structural risk minimization. The latter allows us to evaluate the suitability of population models while clarifying the relevant covariates that explain empirical observations of snail abundance under the actual climatic forcings experienced by the various field sites. Our results link quantitatively hydrological drivers to distinct population dynamics through specific density feedbacks, and show that statistical methods based on model averaging provide reliable snail abundance projections. The consistency of our ranking results suggests the use of ad hoc models of snail demography depending on habitat type (e.g., natural vs. man-made) and hydrological characteristics (e.g., ephemeral vs. permanent). Implications for risk mapping and space-time allocation of control measures in schistosomiasis-endemic contexts are discussed.

  11. p63 gene structure in the phylum mollusca.

    Science.gov (United States)

    Baričević, Ana; Štifanić, Mauro; Hamer, Bojan; Batel, Renato

    2015-08-01

    Roles of p53 family ancestor (p63) in the organisms' response to stressful environmental conditions (mainly pollution) have been studied among molluscs, especially in the genus Mytilus, within the last 15 years. Nevertheless, information about gene structure of this regulatory gene in molluscs is scarce. Here we report the first complete genomic structure of the p53 family orthologue in the mollusc Mediterranean mussel Mytilus galloprovincialis and confirm its similarity to vertebrate p63 gene. Our searches within the available molluscan genomes (Aplysia californica, Lottia gigantea, Crassostrea gigas and Biomphalaria glabrata), found only one p53 family member present in a single copy per haploid genome. Comparative analysis of those orthologues, additionally confirmed the conserved p63 gene structure. Conserved p63 gene structure can be a helpful tool to complement or/and revise gene annotations of any future p63 genomic sequence records in molluscs, but also in other animal phyla. Knowledge of the correct gene structure will enable better prediction of possible protein isoforms and their functions. Our analyses also pointed out possible mis-annotations of the p63 gene in sequenced molluscan genomes and stressed the value of manual inspection (based on alignments of cDNA and protein onto the genome sequence) for a reliable and complete gene annotation.

  12. Molluscicidal and Mosquitocidal Activities of the Essential oils of Thymus capitatus Hoff. et Link. and Marrubium vulgare L.

    Directory of Open Access Journals (Sweden)

    Maha M. Salama

    2012-10-01

    Full Text Available Steam distillation of essential oils of aerial parts of Thymus capitatus and Marrubium vulgare L. collected at North cost of Egypt yielded 0.5% and 0.2%, respectively. Results of Gas chromatography-mass spectrometry analyses of the two samples identified 96.27% and 90.19% of the total oil composition for T. capitatus and M. vulgare, respectively. The two oil samples appeared dominated by the oxygenated constituents (88.22% for T. capitatus and 57.50% for M. vulgare, composed of phenols, mainly carvacrol (32.98% and thymol (32.82% in essential oil of T. capitatus, and thymol (34.55% in essential oil of M. vulgare. It was evaluated the molluscicidal activity of T. capitatus and M. vulgare essential oils on adult and eggs of Biomphalaria alexandrina as well as their mosquitocidal activity on Culex pipiens. The LC50 and LC90 of T. capitatus essential oil against adult snails was 200 and 400 ppm/3hrs, respectively, while for M. vulgare it was 50 and 100 ppm/3hrs, respectively. Moreover, M. vulgare showed LC100 ovicidal activity at 200 ppm/24 hrs while T. capitatus oil showed no ovicidal activity. It was verified mosquitocidal activity, with LC50 and LC90 of 100 and 200 ppm/12hrs respectively for larvae, and 200 and 400 ppm/12hrs respectively for pupae of C. pipiens.

  13. Antifungal and molluscicidal saponins from Serjania salzmanniana.

    Science.gov (United States)

    Ekabo, O A; Farnsworth, N R; Henderson, T O; Mao, G; Mukherjee, R

    1996-04-01

    An investigation of Serjania salzmanniana for biologically active substances has led to the isolation of two novel saponins, salzmannianoside A (3-O-[[beta-D- glucopyranosyl-(1-->4)]-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L- arabinopyranosyl] gypsogenin) [3] and salzmannianoside B (3-O-[[beta-D-glucopyranosyl-(1-->4)]-[alpha-L- arabinopyranosyl-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)] -alpha-L-arabinopyranosyl] hederagenin) (4). Two known saponins, pulsatilla saponin D (3-O-[[beta-D- glucopyranosyl-(1-->4)]-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L- arabinopyranosyl] hederagenin) (1) and 3-O-[[beta-D-glucopyranosyl-(1-->4)]-[alpha-L-rhamnopyranosyl-(1-->2)]-a lpha-L- arabinopyranosyl] oleanolic acid (2) were also isolated from this plant. The structures of 3 and 4 were elucidated by FABMS and 2D NMR techniques. All these four saponins were mollusicidal, causing 70-100% mortality at 10 ppm against Biomphalaria alexandrina, a vector of Schistosoma mansoni in the Nile Valley. The saponins also showed antifungal activity against Cryptococcus neoformans and Candida albicans at minimal inhibitory concentrations of 8 and 16 micrograms/mL, respectively.

  14. Schistosoma mansoni: quantification of skin penetration and early migration by differential external radioassay and autoradiography

    Energy Technology Data Exchange (ETDEWEB)

    Georgi, J.R. (New York State College of Veterinary Medicine, Ithaca (USA))

    1982-04-01

    Eleven gamma-emitting radionuclides (/sup 49/Sc, /sup 54/Mn, /sup 59/Fe, /sup 60/Co, /sup 65/Zn, /sup 75/Se (as selenomethionine, selenocystine, selenite and selenate), /sup 109/Cd, /sup 125/Sb, /sup 133/Ba, /sup 137/Cs and /sup 203/Hg) were screened as labelling agents for Schistosoma mansoni cercariae by incubation of infected Biomphalaria glabrata snails in radioactive solution. Only (/sup 75/Se)methionine yielded satisfactorily labelled cercariae. Differential external radioassay, a new technique employing partial body shielding within a total body counter, permitted separate estimation of tail and body radioactivity of conscious mice previously exposed by tail immersion to /sup 75/Se-labelled cercariae, with measurements repeated as often as desired. Approximately 39% of the /sup 75/Se present in emergent cercariae was retained by schistosomula transformed in vitro but this was subject to considerable variation, especially in schistosomula transformed in vivo. Secreted or catabolized label from penetrant cercariae and schistosomula was rapidly removed from the skin by the bloodstream. Numbers of schistosomula in tail skin were directly proportional to the number of reduced silver foci counted on tail autoradiograms; only a very small fraction of tail radioactivity represented unbound ('spurious') label. Migration of schistosomula away from skin was 50% complete at 3.8-4.3 days, as determined by probit analysis of autoradiographic data.

  15. Relação entre a patogenicidade do Schistosoma mansoni em camundongos e a susceptibilidade do molusco vetor: III. Mortalidade, pesos corporal e das vísceras

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    Zanotti-Magalhães Eliana Maria

    1995-01-01

    Full Text Available Estudou-se a relação entre o desenvolvimento da hepatomegalia, da esplenomegalia, peso corporal e taxa de mortalidade em camundongos experimentalmente infectados por Schistosoma mansoni com o grau de susceptibilidade de Biomphalaria glahrata e B. tenagophila nas quais se desenvolveram as cercárias infectantes respectivamente, das linhagens BH e SJ. Foram utilizados como hospedeiro definitivo camundongos Swiss, SPF e como hospedeiros intermediários populações de moluscos selecionados geneticamente para o caráter susceptibilidade. Foram observados menores pesos corporais e das visceras em camundongos infectados com cercárias provenientes de moluscos que apresentaram elevado grau de susceptibilidade. A maior susceptibilidade dos moluscos à infecção pelo S. mansoni correspondeu a uma menor sobrevivência dos camundongos infectados. Os resultados fazem crer que a maior adaptação do parasita ao hospedeiro intermediário, traduzidos pelas taxas mais elevadas de susceptibilidade, pode levar a um comportamento diferente deste parasita no hospedeiro definitivo.

  16. Sobre um foco urbano de esquistossomose em área metropolitana da região sudeste do Brasil

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    Guimarães Carlos Tito

    1993-01-01

    Full Text Available Descreve-se foco de transmissão ativa de esquistossomose mansoni em Belo Horizonte, MG, Brasil, localizado no Parque "Julien Rien", uma área de lazer com 48.500 m², criada pela Prefeitura Municipal, em 1980, na zona sul da cidade. Em capturas feitas durante 10 anos (1983-1992 foram coletados 3.361 exemplares de Biomphalaria glabrata (diâmetro médio= 9,3 mm, dos quais 23 (0,7% estavam infectados pelo Schistosoma mansoni. O encontro de moluscos hospedeiros intermediários do S. mansoni em áreas urbanizadas (pequenos lagos artificiais cimentados de parques, jardins, prédios públicos, e outros pode estar relacionado com a introdução de peixes e plantas aquáticas. É sugerida, como medida profilática, a não introdução de peixes e plantas aquáticas nesses locais, a não ser após período de quarentena de, no mínimo, 30 dias.

  17. The development of snail control methods on an irrigated sugar-cane estate in northern Tanzania.

    Science.gov (United States)

    Fenwick, A

    1970-01-01

    In an attempt to prevent the transmission of Schistosoma mansoni on an irrigated sugar-cane estate, molluscicide experiments were carried out to find the optimum methods for controlling the intermediate-host snails, Biomphalaria pfeifferi. The ease of application of N-tritylmorpholine led to its adoption as the molluscicide of choice for the two separate irrigation systems on the estate. Experiments on the frequency and duration of molluscicide treatments were carried out, and from these it was concluded that 5-day applications of N-tritylmorpholine at 0.025 ppm every 7 weeks might lead to a break in transmission by control of the snails.In another set of trials, drainage ditches were treated alternately with N-tritylmorpholine and niclosamide ethanolamine salt, and although the chemicals differed only slightly in their effect, the latter-being ovicidal-was chosen to be applied at approximately 4 ppm by knapsack sprayer every 8 weeks. Extra treatment of small pools with the same compound was carried out during the long rains when irrigation was unnecessary and most of the canals were dry.It is pointed out that the effect of the control methods on S. mansoni transmission will need to be evaluated by studying the incidence of the disease in the population.

  18. Molluscan cells in culture: primary cell cultures and cell lines.

    Science.gov (United States)

    Yoshino, T P; Bickham, U; Bayne, C J

    2013-06-01

    In vitro cell culture systems from molluscs have significantly contributed to our basic understanding of complex physiological processes occurring within or between tissue-specific cells, yielding information unattainable using intact animal models. In vitro cultures of neuronal cells from gastropods show how simplified cell models can inform our understanding of complex networks in intact organisms. Primary cell cultures from marine and freshwater bivalve and gastropod species are used as biomonitors for environmental contaminants, as models for gene transfer technologies, and for studies of innate immunity and neoplastic disease. Despite efforts to isolate proliferative cell lines from molluscs, the snail Biomphalaria glabrata Say, 1818 embryonic (Bge) cell line is the only existing cell line originating from any molluscan species. Taking an organ systems approach, this review summarizes efforts to establish molluscan cell cultures and describes the varied applications of primary cell cultures in research. Because of the unique status of the Bge cell line, an account is presented of the establishment of this cell line, and of how these cells have contributed to our understanding of snail host-parasite interactions. Finally, we detail the difficulties commonly encountered in efforts to establish cell lines from molluscs and discuss how these difficulties might be overcome.

  19. Biological studies on the snail intermediate hosts of schistosomiasis with a special emphasis on using larval echinostomes as biocontrol agent against larval schistosomes and snails.

    Science.gov (United States)

    Rashed, A A

    2002-12-01

    The present investigation deals with the infectivity of the two snail intermediate hosts of schistosomiasis, Biomphalaria alexandrina and Bulinus truncatus collected from nine drains in Sharkia Governorate, Egypt. The rate of infection among the snails was general low being 0% in many drains. Regarding B. alexandrina, the rate of infection ranged from 4-16%, and in B. truncatus ranged from 4-8%. Infection with larval echinostomes was dominant over larval schistosomes in the two snail vectors. The distribution of larval schistosomes was restricted to the hepatopancreas of the two snail vectors, while larval echinostomes were distributed in head, foot, kidney, haemocoelic cavity, hepatopancreas...etc. The predation of larval schistosomes by larval echinostomes and the severe histopathological effects induced by larval ecbinostomes strongly enhances using them as biocontrol agent. The physico-chemical parameters and pollution condition in the drains seem to have no effect on the process of snails infectivity. It is concluded that larval echinostomes can resist the polluting conditions in the drain. The two snail vectors exhibit very minimal or rare host response against larval echinostomes. Probably, the toxicants and pollutants in the drain may act as stressor that makes the snails much more susceptible to infection by larval trematodes.

  20. Evaluation of the toxicity and molluscicidal and larvicidal activities of Schinopsis brasiliensis stem bark extract and its fractions

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    Clisiane C.S. Santos

    2014-06-01

    Full Text Available Dengue fever and schistosomiasis are major public health issues for which vector control using larvicide and molluscicide substances present in plants provides a promising strategy. This study evaluated the potential toxicity of the extract of hydroethanol Schinopsis brasiliensis Engl., Anacardiaceae, stem bark and its chloroform, hexane, ethyl acetate, and hydromethanol fractions against Artemia salina and Aedes Aegypti larvae and snails Biomphalaria glabrata. All of the assays were performed in triplicate and the mean mortality rates were used to determine the LC50and LC90 values using the probit method. The hydroethanol hydromethanol extract and fraction were free of toxicity towards A. salina(LC50 > 1000 µg/ml, while chloroform fraction was moderately toxic (LC50313 µg/ml; ethyl acetate and hexane fractions displayed low toxicity, with LC50 557 and 582 µg/ml, respectively. Chloroform, hexane, and ethyl acetate fractions showed larvicidal potential towards A. aegypti (LC50 values of 345, 527 and 583 µg/ml, respectively, while chloroform and ethyl acetate fractions were highly toxic to B. glabrata (LC90values of 68 and 73 µg/ml, respectively. Based on these findings, ethyl acetate, chloroform, and hexane fractions should be further investigated for their potential use against the vectors of dengue and schistosomiasis.

  1. Molluscicidal activity of chlorophyll extraction against the freshwater snails

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    Mona Said Mahmoud

    2013-09-01

    Full Text Available Objective: To evaluate the molluscicidal activity of chlorophyll extract as a photodynamic substance against the snails Lymnaea stagnalis, Biomphalaria spp. and Physa marmorata. Methods: Chlorophyllin was extracted from deep-frozen spinach. Snails were incubated in chlorophyllin containing water with 2.5, 5.0, 10.0 and 15.0 µg/mL. All samples were kept in darkness overnight for incubation. After incubation, three samples were irradiated with simulated solar radiation for 3 h. After irradiation, the vitality of the organisms was determined. Results: The photodynamically active chlorophyllin, at low concentrations, was able to kill snails within a few hours under exposure of solar radiation. Besides, it had a killing effect by about 70% and 100% on the snails’ eggs and the newly hatched snails, respectively, after 3 h exposure to solar radiation. Conclusion: The derivates of chlorophyll was a very interesting substance for photodynamic freshwater snail control. Hence, it might be a promising and cheap new strategy which probably had the potential to replace the synthetic molluscicides for snail control.

  2. Evaluation of the antischistosomal activity of sulfated α-D-glucan from the lichen Ramalina celastri free and encapsulated into liposomes

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    R.V.S. Araújo

    2011-04-01

    Full Text Available The antischistosomal activity of the sulfated polysaccharide α-D-glucan (Glu.SO4 extracted from Ramalina celastri was evaluated after encapsulation into liposomes (Glu.SO4-LIPO in Schistosoma mansoni-infected mice. The effect of treatment with Glu.SO4 and Glu.SO4-LIPO (10 mg/kg on egg elimination, worm burden and hepatic granuloma formation was assessed using female albino Swiss mice, 35-40 days of age, weighing 25 ± 2 g, infected with 150 cercariae/animal (Biomphalaria glabrata, BH strain. Four groups (N = 10 were studied, two controls (empty liposomes and NaCl and two treated groups (Glu.SO4-LIPO and Glu.SO4 using a single dose. Parasitological analysis revealed that Glu.SO4-LIPO was as efficient as Glu.SO4 in reducing egg elimination and worm burden. Treatment with free Glu.SO4 and Glu.SO4-LIPO induced a statistically significant reduction in the number of granulomas (62 and 63%, respectively. Lectin histochemistry showed that wheat germ agglutinin intensely stained the egg-granuloma system in all treated groups. On the other hand, peanut agglutinin stained cells in the control groups, but not in the treated groups. The present results suggest a correlation between the decreasing number of hepatic egg-granulomas and the glycosylation profile of the egg-granuloma system in animals treated with free Glu.SO4 or Glu.SO4-LIPO.

  3. Social Organization in Parasitic Flatworms--Four Additional Echinostomoid Trematodes Have a Soldier Caste and One Does Not.

    Science.gov (United States)

    Garcia-Vedrenne, Ana E; Quintana, Anastasia C E; DeRogatis, Andrea M; Martyn, Kayla; Kuris, Armand M; Hechinger, Ryan F

    2016-02-01

    Complex societies where individuals exhibit division of labor with physical polymorphism, behavioral specialization, and caste formation have evolved several times throughout the animal kingdom. Recently, such complex sociality has been recognized in digenean trematodes; evidence is limited to 6 marine species. Hence, the extent to which a soldier caste is present throughout the Trematoda is sparsely documented, and there are no studies detailing the structure of a species lacking such a social structure. Here we examine colony structure for an additional 5 echinostomoid species, 4 of which infect the marine snail Cerithidea californica and 1 (Echinostoma liei) that infects the freshwater snail Biomphalaria glabrata . For all species, we present redia morphology (pharynx and body size) and the distribution of individuals of different castes throughout the snail body. When morphological evidence indicated the presence of a soldier caste, we assessed behavior by measuring attack rates of the different morphs toward heterospecific trematodes. Our findings indicate that each of the 4 species from C. californica have a permanent soldier caste while E. liei does not. The observed intra- and inter-specific variation of caste structure for those species with soldiers, and the documentation of colony structure for a species explicitly lacking permanent soldiers, emphasizes the diverse nature of trematode sociality and the promise of the group to permit comparative investigations of the evolution and ecology of sociality.

  4. Taxonomic revision of the fossil pulmonate mollusks of Itaboraí Basin (Paleocene, Brazil

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    Rodrigo Brincalepe Salvador

    2013-01-01

    Full Text Available The limestones of Itaboraí Basin (Middle Paleocene, Rio de Janeiro, Brazil, harbor a rich fossil molluscan fauna consisting exclusively of pulmonate snails, both terrestrial and freshwater. An extensive taxonomic revision of this paleofauna is conducted here. A new genus, Cortana, is described as well as two new species, Eoborus fusiforme and Gastrocopta itaboraiensis. The revised classification is as follows: Austrodiscus lopesi (Charopidae; Biomphalaria itaboraiensis (Planorbidae; "Brachypodella" britoi (Urocoptidae; Brasilennea arethusae, Brasilennea guttula, Brasilennea minor (Cerionidae; Bulimulus fazendicus, Bulimulus trindadeae, Cortana carvalhoi, Cyclodontina coelhoi, Itaborahia lamegoi, Leiostracus ferreirai, Plagiodontes aff. dentatus (Orthalicidae; Cecilioides sommeri (Ferussaciidae; Eoborus rotundus, Eoborus sanctijosephi, Eoborus fusiforme (Strophocheilidae; Gastrocopta mezzalirai, Gastrocopta itaboraiensis (Gastrocoptidae; Temesa magalhaesi (Clausiliidae. The species Strobilopsis mauryae was considered a synonym of Brasilennea arethusae; Bulimulus sommeri a synonym of Itaborahia lamegoi; and Vorticifex fluminensis a synonym of Eoborus sanctijosephi. Itaboraí Basin has the most ancient records of the families Orthalicidae, Gastrocoptidae, Ferussaciidae and Strophocheilidae. Moreover, the basin's records of Charopidae, Clausiliidae, Cerionidae, and Urocoptidae are among the most ancient in the world and, among these, those of Cerionidae, Clausiliidae and Urocoptidae deserve special attention since they are greatly removed from these families' current distribution. Additionally, Itaboraí has the most ancient records for the genera Austrodiscus, Brachypodella, Bulimulus, Cecilioides, Cyclodontina, Eoborus, Gastrocopta, Leiostracus, Plagiodontes and Temesa. There are three endemic genera in the basin: Brasilennea, Cortana and Itaborahia. Further discussion on paleobiogeography and evolution of this paleofauna is also provided.

  5. Micronuclei as biomarkers of genotoxicity of gamma radiation in aquatic environments

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Luanna R.S.; Silva, Edvane B.; Melo, Ana M.M.A. [Universidade Federal de Pernambuco (GERAR/DEN/UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia; Silva, Ronaldo C. da [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Genetica; Amancio, Francisco F. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia. Lab. de Radiobiologia

    2011-07-01

    Ionizing radiation is a genotoxic agent, inducing gene mutations and cellular death. Several efforts have been defendants in the development of techniques for measurement of radiation damage in biological systems. Among these techniques, micronuclei test has been showing as a great bio marker of DNA damage, being used in environmental monitoring to detect genotoxic agents in the environment. Additionally, organisms as Biomphalaria glabrata, freshwater molluscs, presents itself as an excellent model to assess damage caused by physical and chemical agents, due their biological and environmental characteristics. The snails were divided into groups of 5 individuals exposed to doses of 0 (control), 25, 35, 45 and 55 Gy of {sup 60}Co. After 48 hours of irradiation, the hemo lymph was collected and prepared the slides, which were stained with Giemsa and analyzed the cellular changes in haemocytes Statistical analysis was accomplished through chi-square test, ANOVA and Tukey test (p< 0,05). The results indicated that B. glabrata showed to be sensitive to gamma radiation. The snails irradiated with 35 Gy showed a decrease of haemocytes, while that of 55 Gy increased. Cellular and morphological changes were observed at doses of 35, 45 and 55 Gy and the dose of 55 Gy, the most radiotoxic. (author)

  6. Spatial distribution of schistosomiasis foci on Itamaracá Island, Pernambuco, Brazil

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    CS Barbosa

    2004-08-01

    Full Text Available Acute cases of schistosomiasis have been found on the coastal area of Pernambuco, Brazil, due to environmental disturbances and disorderly occupation of the urban areas. This study identifies and spatially marks the main foci of the snail host species, Biomphalaria glabrata on Itamaracá Island. The chaotic occupation of the beach resorts has favoured the emergence of transmission foci, thus exposing residents and tourists to the risk of infection. A database covering five years of epidemiological investigation on snails infected by Schistosoma mansoni in the island was produced with information from the geographic positioning of the foci, number of snails collected, number of snails tested positive, and their infection rate. The spatial position of the foci were recorded through the Global Positioning System (GPS, and the geographical coordinates were imported by AutoCad. The software packages ArcView and Spring were used for data processing and spatial analysis. AutoCad 2000 was used to plot the pairs of coordinates obtained from GPS. Between 1998 and 2002 5009 snails, of which 12.2% were positive for S. mansoni, were collected in Forte Beach. A total of 27 foci and areas of environmental risk were identified and spatially analyzed allowing the identification of the areas exposed to varying degrees of risk.

  7. Studies on the biology of schistosomiasis with emphasis on the Senegal river basin

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    Southgate VR

    2001-01-01

    Full Text Available The construction of the Diama dam on the Senegal river, the Manantali dam on the Bafing river, Mali and the ensuing ecological changes have led to a massive outbreak of Schistosoma mansoni in Northern Senegal, associated with high intensity of infections, due to intense transmission, and the creation of new foci of S. haematobium. Data on the vectorial capacity of Biomphalaria pfeifferi from Ndombo, near Richard Toll, Senegal are presented with sympatric and allopatric (Cameroon S. mansoni. Comparisons are made on infectivity, cercarial production, chronobiology of cercarial emergence and longevity of infected snails. Recent data on the intermediate host specificity of different isolates of S. haematobium from the Lower and Middle Valley of the Senegal river basin (SRB demonstrate the existence of at least two strains of S. haematobium. The role of Bulinus truncatus in the transmission of S. haematobium in the Lower and Middle Valleys of the SRB is reviewed. Both S. haematobium and S. mansoni are transmitted in the same foci in some areas of the SRB.

  8. Molluscicidal activity of chlorophyll extraction against the freshwater snails

    Institute of Scientific and Technical Information of China (English)

    Mona Said Mahmoud; Peter Richter; Hatem Abdel Mawgoud Shalaby; Omnia Mohamed Kandil; Donat-Peter Hder

    2013-01-01

    Objective: To evaluate the molluscicidal activity of chlorophyll extract as a photodynamic substance against the snails Lymnaea stagnalis, Biomphalaria spp. and Physa marmorata.Methods:Chlorophyllin was extracted from deep-frozen spinach. Snails were incubated in chlorophyllin containing water with 2.5, 5.0, 10.0 and 15.0 µg/mL. All samples were kept in darkness overnight for incubation. After incubation, three samples were irradiated with simulated solar radiation for 3 h. After irradiation, the vitality of the organisms was determined. Results: The photodynamically active chlorophyllin, at low concentrations, was able to kill snails within a few hours under exposure of solar radiation. Besides, it had a killing effect by about 70%and 100% on the snails’ eggs and the newly hatched snails, respectively, after 3 h exposure to solar radiation.Conclusion:The derivates of chlorophyll was a very interesting substance for photodynamic freshwater snail control. Hence, it might be a promising and cheap new strategy which probably had the potential to replace the synthetic molluscicides for snail control.

  9. Studies on the molluscicidal activity of Agave angustifolia and Pittosporum tobira on schistosomiasis transmitting snails.

    Science.gov (United States)

    Ibrahim, Abdalla M; Abdel-Gawad, Mahfouz M; El-Nahas, Hanan A; Osman, Nadia S

    2015-04-01

    In the search for new molluscicidal plants for controlling the snail vectors of schistosomiasis, laboratory evaluation was made to assess the molluscicidal activity of Agave angustifolia and Pittosporum tobira plants against Biomphalaria alexandrina snails. Results indicated that both plants have promising molluscicidal activity as the LC90 of the dry powder of both plants was 120 ppm. Both plants showed marked cercaricidal and miracidicidal potencies against S. mansoni larvae. The LC90 of both plants (120 ppm) killed most B. alexandrina eggs within 24 h of exposure. The sub-lethal concentrations of both plants markedly suppressed the survival rate of B. alexandrina snails and the mortality increased with increasing the concentrations and the exposure period up to 10 successive weeks. The accumulative toxic effect of these concentrations was continuous during the recovery period. Also, the reproductive rates of exposed snails were greatly affected even through the recovery period. This depression in reproductive ability of snails was accompanied by histological damage in the hermaphrodite glands of exposed snails. Meanwhile, the growth of snails was estimated weekly and it showed great inhibition in exposed snails comparing with the control ones.

  10. Drug resistance in Schistosomiasis: a review

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    John I. Bruce

    1987-01-01

    Full Text Available Drug resistance associated with the treatment of human schistosomiasis appears to be an emerging problem requiring more attention from the scientific community than the subject currently receives. Drug-resistant strains of Schistosoma mansoni have been isolated by various investigators as a result of laboratory experimentation or from a combination of field and laboratory studies. Review of this data appears to indicate that the lack of susceptibility observed for some of the isolated strains cannot be ascribed solely to previous administration of antischistosome drugs and thus further studies are required to elucidate this phenomena. Strains of S. mansoni have now been identified from Brazil which are resistant to oxamniquine, hycanthone and niridazole; from Puerto Rico which are resistant to hycanthone and oxamniquine; and from Kenya which are resistant to niridazole and probably oxamniquine. Strains derived by in vitro selection and resistant to oxamniquine and possibly to oltipraz are also available. All of these strains are currently maintained in the laboratory in snails and mice, thus providing for the first time an opportunity for indepth comparative studies. Preliminary data indicates that S. haematobium strains resistant to metrifonate may be occurring in Kenya. This problem could poise great difficulty in the eventual development of antischistosomal agents. Biomphalaria glabrata from Puerto Rico and Brazil were found to be susceptible to drug-resistant S. mansoni from each country.

  11. Schistosomiasis mansoni in areas of low transmission: epidemiological characterization of Venezuelan foci

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    Alarcón de Noya B

    2002-01-01

    Full Text Available Severe schistosomiasis is a rare event in Venezuela nowadays, after a successful national campaign by the Schistosomiasis Control Program. Unfortunately, this program has practically disappeared, and snail surveillance in field is not a priority, anymore. Thus, schistosomiasis has become a neglected disease in this country. However, surveys in different populations from the endemic area have shown particular epidemiological features described herein. In five communities we evaluated 2,175 persons and searched for the presence of Biomphalaria glabrata snails. Some markers were used for classifying schistosomiasis foci: mean age of the persons with Schistosoma mansoni eggs in the stools, serological tests, presence of B. glabrata snails, and intensity of infection. Places without B. glabrata snails and with few schistosomiasis cases were defined as "past transmission sites"; a site with abundant snails but few cases was defined as "potential risk"; "new transmission" foci were characterized by the presence of infected snails and young people passing eggs in the stools. A "re-emergent" focus has shared these last features, showing in addition a place where schistosomiasis had been reported before. Recent evidences of active transmission with the increasing dispersion of B. glabrata snails, point out the necessity for the re-establishment of the Schistosomiasis Control Program in Venezuela.

  12. Acute schistosomiasis diagnosis: a new tool for the diagnosis of schistosomiasis in a group of travelers recently infected in a new focus of Schistosoma mansoni

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    Rafaella Fortini Queiroz Grenfell

    2013-04-01

    Full Text Available Introduction The diagnosis of schistosomiasis mansoni on early stages of infection is important to prevent late morbidity. A simple, cheap, sensitive and specific assay for routine diagnosis of schistosome infection based on the detection of specific IgG for schistosomula tegument antigens (ELISA-SmTeg was developed by our group. Methods We describe here an acute outbreak involving a travel group of 80 individuals from a non-endemic area of the State of Minas Gerais, Brazil. These individuals were in contact with a freshwater pool where Biomphalaria glabrata was found. Results obtained from our new methodology were compared to IgG antibody titers against soluble worm antigenic preparation (SWAP by ELISA and, also to parasitological examination, nuclear magnetic resonance and clinical findings. Results ELISA-SmTeg was capable of detecting 64 positive cases among the 80 individuals participating at the survey with a positivity ratio of 80% and a higher sensitivity than ELISA-SWAP that was only sensitive for 56% of positive cases. Besides, a significant correlation was found for the severity of the infection and the specific IgG titers against SmTeg. Conclusions Our data showed that ELISA-SmTeg might serve as the initial diagnostic tool for acute stages of the infection in community-based helminth control programs or for the surveillance of individuals from non-endemic areas.

  13. Acute schistosomiasis outbreak in the metropolitan area of Belo Horizonte, Minas Gerais: alert about the risk of unnoticed transmission increased by growing rural tourism

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    Martin J Enk

    2003-09-01

    Full Text Available The present article describes the occurrence of 17 cases of acute schistosomiasis in the metropolitan area of Belo Horizonte, state of Minas Gerais, Brazil. All individuals affected took a bath in a swimming pool of a holiday resort that was provided with water from a nearby brook. The apparently clean water and the absence of snails in the pool gave the wrong impression that there was no risk for infection. During a malacological survey at the site snails of the species Biomphalaria glabrata were found and tested positive for Schistosoma mansoni. All the patients live in the middle-class area of Barreiro, metropolitan area of Belo Horizonte and have medium grade school education. The difficulties in establishing the right diagnosis is expressed by the search for medical attention in 17 different medical facilities, the wide range of laboratory test and the inadequate treatment administration. A lack of knowledge about the disease was found in all groups studied. The booming rural tourism in endemic areas is identified as a probable risk factor for infection, especially for individuals of the non-immune middle and upper class parts of the society in urban centers. Special attention is given to a multidisciplinary approach to the complex issue of disease control and prevention.

  14. Modelling spatial distribution of snails transmitting parasitic worms with importance to human and animal health and analysis of distributional changes in relation to climate

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    Ulrik B. Pedersen

    2014-05-01

    Full Text Available The environment, the on-going global climate change and the ecology of animal species determine the localisation of habitats and the geographical distribution of the various species in nature. The aim of this study was to explore the effects of such changes on snail species not only of interest to naturalists but also of importance to human and animal health. The spatial distribution of freshwater snail intermediate hosts involved in the transmission of schistosomiasis, fascioliasis and paramphistomiasis (i.e. Bulinus globosus, Biomphalaria pfeifferi and Lymnaea natalensis were modelled by the use of a maximum entropy algorithm (Maxent. Two snail observation datasets from Zimbabwe, from 1988 and 2012, were com- pared in terms of geospatial distribution and potential distributional change over this 24-year period investigated. Climate data, from the two years were identified and used in a species distribution modelling framework to produce maps of pre- dicted suitable snail habitats. Having both climate- and snail observation data spaced 24 years in time represent a unique opportunity to evaluate biological response of snails to changes in climate variables. The study shows that snail habitat suit- ability is highly variable in Zimbabwe with foci mainly in the central Highveld but also in areas to the South and West. It is further demonstrated that the spatial distribution of suitable habitats changes with variation in the climatic conditions, and that this parallels that of the predicted climate change.

  15. LSENS - GENERAL CHEMICAL KINETICS AND SENSITIVITY ANALYSIS CODE

    Science.gov (United States)

    Bittker, D. A.

    1994-01-01

    which provides the relationships between the predictions of a kinetics model and the input parameters of the problem. LSENS provides for efficient and accurate chemical kinetics computations and includes sensitivity analysis for a variety of problems, including nonisothermal conditions. LSENS replaces the previous NASA general chemical kinetics codes GCKP and GCKP84. LSENS is designed for flexibility, convenience and computational efficiency. A variety of chemical reaction models can be considered. The models include static system, steady one-dimensional inviscid flow, reaction behind an incident shock wave including boundary layer correction, and the perfectly stirred (highly backmixed) reactor. In addition, computations of equilibrium properties can be performed for the following assigned states, enthalpy and pressure, temperature and pressure, internal energy and volume, and temperature and volume. For static problems LSENS computes sensitivity coefficients with respect to the initial values of the dependent variables and/or the three rates coefficient parameters of each chemical reaction. To integrate the ODEs describing chemical kinetics problems, LSENS uses the packaged code LSODE, the Livermore Solver for Ordinary Differential Equations, because it has been shown to be the most efficient and accurate code for solving such problems. The sensitivity analysis computations use the decoupled direct method, as implemented by Dunker and modified by Radhakrishnan. This method has shown greater efficiency and stability with equal or better accuracy than other methods of sensitivity analysis. LSENS is written in FORTRAN 77 with the exception of the NAMELIST extensions used for input. While this makes the code fairly machine independent, execution times on IBM PC compatibles would be unacceptable to most users. LSENS has been successfully implemented on a Sun4 running SunOS and a DEC VAX running VMS. With minor modifications, it should also be easily implemented on other

  16. Avaliação das atividades antimicrobiana, citotóxica, moluscicida e antioxidante de Bromelia antiacantha Bertol. (Bromeliaceae Evaluation of antimicrobial, cytotoxic, molluscicidal and antioxidant activities of Bromelia antiacantha Bertol. (Bromeliaceae

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    L.M. Manetti

    2010-12-01

    Full Text Available A Bromelia antiacantha Bertol. (Bromeliaceae, conhecida como gravatá ou caraguatá, apresenta características medicinais, alimentícias e ornamentais. Neste trabalho foram avaliadas as atividades antifúngica, antibacteriana, citotóxica, moluscicida e antioxidante de extratos alcoólicos das folhas e frutos desta espécie. Na avaliação da atividade antimicrobiana pelo método de microdiluição os extratos alcoólicos não foram eficientes frente à cepa referência do fungo Candida albicans (ATCC 90028, cepas clínicas de C. albicans e C. glabrata, e frente às bactérias S. aureus (ATCC 6538, P. aeruginosa (ATCC 9027 e E. coli (ATCC 8739. A atividade citotóxica, avaliada pelo bioensaio de toxicidade sobre náuplios de Artemia salina Leach (TAS, foi positiva para ambos extratos, com valores de DL50 variando em torno de 620 µg mL-1 e 360 µg mL-1, para os extratos alcoólicos dos frutos e das folhas, respectivamente. A atividade moluscicida, avaliada frente a caramujos da espécie Biomphalaria glabrata (Molusca, Gastropoda, não mostrou toxicidade aguda para soluções de 400 µg mL-1. As propriedades antioxidantes dos extratos investigadas in vitro mediante o método de DPPH• foram consideradas modestas (~ 35% de inibição na concentração de 1000 µg mL-1. Dentre as atividades biológicas que foram testadas a atividade citotóxica foi a mais pronunciada.Bromelia antiacantha Bertol. (Bromeliaceae, popularly known as "gravatá" or "caraguatá", shows medicinal, nutritional and ornamental properties. In the present study, the alcoholic extracts of leaves and fruits of this species were evaluated for antifungal, antibacterial, cytotoxic, molluscicidal and antioxidant activities. The alcoholic extracts evaluated by microdilution method were not efficient against the standard strain of Candida albicans (ATCC 90028, clinical strains of C. albicans and C. glabrata, and S. aureus (ATCC 6538, P. aeruginosa (ATCC 9027 and E. coli (ATCC 8739

  17. The phytochemistry and biological aspects of Caryocaraceae family Aspectos fitoquímicos e biológicos da família Caryocaraceae

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    J. Ascari

    2013-01-01

    Full Text Available The Caryocaraceae family is constituted of 25 species distributed in two genera (Caryocar and Anthodiscus. Plants of this family have been used in several phytochemical studies for isolation and characterization of chemical compounds. Some of these studies evaluated in vitro and in vivo biological activities of extracts and pure substances isolated from plants of this family. Nine species of Anthodiscus genus have been described, while no phytochemical study related to them has been reported. On the other hand, Caryocar genus presents 16 species with several medicinal uses like for the treatment of colds and bronchitis, in the prevention of tumours, as a regulating agent of the menstrual flow, to treat ophthalmological problems and for the cure of hematomas and bruises. Some species of this genus were targeted by phytochemical studies and presented, in their composition, the following classes of secondary metabolites: triterpenes, fatty acids, tannins, carotenoids, triterpenic saponins, phenolic coumarins, phenolic glycosides, and others. The fruits of Caryocar species are very nutritive, containing in their composition fibers, proteins, carbohydrates and minerals. Seeds have been widely used as oil source with nutritional and cosmetic value. The biological evaluation of some species was carried out by using relevant biological assays such as: antioxidant, allelopathic and antifungal activities against Biomphalaria glabrata and toxicity on Artemia salina.A família Caryocaraceae é constituída por 25 espécies distribuídas em dois gêneros (Caryocar e Anthodiscus. Plantas desta família têm sido utilizadas em diversos estudos fitoquímicos para isolamento e caracterização de constituintes químicos. Alguns destes estudos avaliaram atividades biológicas in vitro e in vivo de extratos e substâncias puras isoladas a partir de plantas desta família. São descritas nove espécies dentro do gênero Anthodiscus e nenhum estudo fitoqu

  18. Avaliação da esquistossomose e de outras parasitoses intestinais, em escolares do município de Bambuí, Minas Gerais, Brasil Evaluation of the schistosomiasis and others intestinal parasitosis in the school children of Bambuí county, Minas Gerais, Brazil

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    Roberto Sena Rocha

    2000-10-01

    Full Text Available O objetivo desse trabalho foi determinar a prevalência das parasitoses em escolares de Bambuí, através de exames coprológicos (direto e Kato-Katz e reavaliar os criadouros de moluscos descritos no município. Dos 2.901 escolares examinados, 20,1% estavam parasitados, sendo que Giardia lamblia, Entamoeba coli, Ascaris lumbricoides e ancilostomídeos foram os parasitas mais freqüentes, com prevalências de 6,2%, 6,2%, 4,8% e 1,4%, respectivamente. Os ancilostomídeos foram significativamente mais freqüentes na zona rural e nos alunos com mais de 14 anos, enquanto a prevalência da E. coli foi maior na zona urbana e a G. lamblia mais freqüente na faixa etária de 0-6 anos. Somente três crianças eliminavam ovos de Schistosoma mansoni. O único hospedeiro intermediário encontrado foi a Biomphalaria glabrata e nenhuma delas estava eliminando cercárias de S. mansoni . Comparando-se estes dados a de levantamentos realizados anteriormente no município, observou-se uma queda na prevalência de todos os parasitas. Algumas hipóteses para tentar explicar esta queda são discutidas tais como: processo intenso de urbanização e a melhoria das condições sócio-sanitárias do município.This work was carried out with the purpose of determining the prevalence of intestinal parasitoses in the school children of Bambuí, through parasitological examinations (direct and Kato-Katz methods and reevaluating the snails' breeding places described in the county. Of the 2,091 school children examined, 20.1% had at least one parasitic infection. Giardia lamblia, Entamoeba coli, Ascaris lumbricoides and hookworm are the most frequent parasites, with a prevalence of 6.2%, 6.2%, 4.8% and 1.4%, respectively. The hookworms were significantly more frequent among students from the rural area and in those aged over 14 years, while the prevalence of E. coli was greater in the urban area and the G. lamblia was more frequent in children under 6 years old. Only three

  19. First records of freshwater molluscs from the ecological reserve El Edén, Quintana Roo, México Primeros registros de moluscos dulceacuícolas de la Reserva Ecológica El Edén, Quintana Roo, México

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    Roberto Cózatl-Manzano

    2007-12-01

    Full Text Available The diversity of the freshwater molluscs at El Edén was unknown. This is the first treatment of them, allowing us to compare spatial and temporal species distribution. Eleven species of freshwater molluscs were found in 2 surveys carried in March (dry season and September (rainy season 1998 at the reserve El Edén. A total of 266 individuals were collected; 8 pulmonates, Mayabina spiculata, Mexinauta impluviatus, Physa sp., Biomphalaria havanensis, Drepanotrema lucidum, Drepanotrema kermatoides, Planorbella (Pierosoma trivolvis, and Planorbula armigera; 2 prosobranchs, Pyrgophorus sp. and Pomacea flagellata; and one bivalve, Musculium transversum. Pulmonata dominate over Prosobranchia species in diversity. No significant differences were observed in diversity between dry and rainy seasons. However, species abundance recorded in both seasons was very low, probably due to a combination of inadequate food resources and disadvantageous climate (periodic conditions of drought and flooding. Further studies using a combination of different sampling methods and more frequent samplings are needed to confirm or identify these factors. We suggest that future studies should focus on cultivation of species with economic potential such as the apple snail Pomacea flagellata.La diversidad de moluscos dulceacuícolas de la Reserva Ecológica El Edén se desconocía; este estudio constituye su primer registro. Asimismo, esta investigación permite comparar la distribución espacial y temporal de las especies registradas. Las recolectas se efectuaron en marzo (temporada de sequía y septiembre (lluvia de 1998. Se registran 11 especies (266 individuos en total, 8 pulmonados: Mayabina spiculata, Mexinauta impluviatus, Physa sp., Biomphalaria havanensis, Drepanotrema lucidum, Drepanotrema kermatoides, Planorbella (Pierosoma trivolvis y Planorbula armigera; dos prosobranquios: Pyrgophorus sp. y Pomacea flagellata, y un bivalvo: Musculium transversum. Los pulmonados

  20. Actividad molusquicida del Piquerol A aislado de Piqueria trinervia (compositae sobre ocho especies de caracoles pulmonados The molluscicide activity of Piquerol A isolated from Piqueria trinervia (Compositae against eight species of pulmonate snails

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    Alejandro Cruz-Reys

    1989-03-01

    Full Text Available De las partes aéreas de la planta Piqueria trinervia (Compositae colectada en diveresas áereas de México, se aisló el Piquerol A. Este compuesto se probó como agente molusquicida contra ocho especies de caracoles pulmonados: Fossaria (Fossaria humilis, F. (Bakerilymnae sp., Pseudosuccinea columella, Stagnicola attenuata, de México; F. (B. cubensis y Physacubensis, de Cuba; P. Columella y Biomphalaria glabrata, de Brasil; B glabrata, de Puerto Rico; S. elodes, de Estados Unidos. Se utilizaron tres concentraciones 50, 25 y 5 ppm para cada una de las especies y 2 períodos de exposición, 6 y 24 horas, a 20-22ºC. En 50 ppm, después de 6 horas, y 25 ppm, después de 24 horas los ejemplares de todas las especies murieron. En 5 ppm después de 24 horas, se observaron mortalidades de 60 a 100%. En ningún caso se observó recuperación después de la exposición por 24 horas. El piquerol A es un terpeno biodegradable que presenta otras actividades biológicas. No se han hecho pruebas de toxicidad en otros animales ni pruebas de campo. Sin embargo, es una substacia con alto potencial de uso como molusquicida en zonas de transmisión focal. Es la primera que en México se hacen estudios sistemáticos sobre molusquicidas de origen vegetal.In laboratory trials an aqueous solution of Piquerol A from Piqueria trinervia, collected in several regions of Mexico, showed a molluscicide action on the adults of eight different pulmonates snails species. Fossaria (Fossaria humilis, F. (Bakerilymnaea sp., Pseudosuccinea columella and Stagnicola attenuata from Mexico; F. (B. cubensis and Physa cubensis from Cuba; P. columella and Biomphalaria glabrata from Brazil; B. glabrata from Puerto Rico; and S. elodes from USA. The solution was tested at 50, 25 and 5 ppm concentration, for two periods of 6 and 24 hours, at room temperature (20-22ºC. A 100% mortality was obtained for all species at 50 ppm concentration after 6 hours of exposure; the same percentage at 25

  1. Moluscos dulceacuícolas exóticos en Chile Exotic freshwater mollusks in Chile

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    Sergio Letelier V.

    2007-10-01

    Full Text Available Las especies de moluscos exóticas dulceacuícolas registradas en esta contribución, corresponden a ejemplares recolectados en humedales en acuarios comerciales o interceptados en barreras aduaneras, así como de referencias bibliográficas. Un total de 7 especies pertenecientes a 6 géneros fueron identificadas: Pomacea bridgesii; Helobia sp.; Thiara (Melanoides tuberculata; Melanoides maculata; Physa sp.; Physella venustula y Biomphalaria sp. Melanoides maculata fue recolectada en el río Lluta y clasificada como especie criptogénica. Los moluscos exóticos recolectados podrían tener éxito en su establecimiento si se considera la vulnerabilidad de los hábitats nativos debido al cambio en las condiciones climáticas globales o a las elevaciones térmicas producidas en el sector costero por los fenómenos de El Niño. En este sentido, las especies subtropicales observadas se podrían considerar como no endémicas y vectores potenciales de zoonosis parasitarias. Las principales vías de introducción de moluscos dulceacuícolas exóticos se derivaron del intercambio comercial, por lo cual, y frente a su incremento interregional, se hace necesario recopilar datos ecológicos y taxonómicos adecuados que permitan evaluar el riesgo de su establecimiento, así como servir de base para la aplicación de futuros tratamientos en bioseguridad.The exotic freshwater mollusk species we report here were collected in wetlands, commercial aquariums, or were given to us by government officials who intercepted some exotic species at customs offices. Other records came from the specialized literature. These species are Pomacea bridgesii; Helobia sp.; Thiara (Melanoides tuberculata; Melanoides maculata; Physa sp., Physella venustula and Biomphalaria sp. It is not clear how Melanoides maculata, found in the Río Lluta, reached Chile. The exotic species collected could expand their ranges in Chilean territory given global environmental and climate change or the

  2. Taxonomic revision of the fossil pulmonate mollusks of Itaboraí Basin (Paleocene, Brazil

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    Rodrigo Brincalepe Salvador

    2013-01-01

    Full Text Available The limestones of Itaboraí Basin (Middle Paleocene, Rio de Janeiro, Brazil, harbor a rich fossil molluscan fauna consisting exclusively of pulmonate snails, both terrestrial and freshwater. An extensive taxonomic revision of this paleofauna is conducted here. A new genus, Cortana, is described as well as two new species, Eoborus fusiforme and Gastrocopta itaboraiensis. The revised classification is as follows: Austrodiscus lopesi (Charopidae; Biomphalaria itaboraiensis (Planorbidae; "Brachypodella" britoi (Urocoptidae; Brasilennea arethusae, Brasilennea guttula, Brasilennea minor (Cerionidae; Bulimulus fazendicus, Bulimulus trindadeae, Cortana carvalhoi, Cyclodontina coelhoi, Itaborahia lamegoi, Leiostracus ferreirai, Plagiodontes aff. dentatus (Orthalicidae; Cecilioides sommeri (Ferussaciidae; Eoborus rotundus, Eoborus sanctijosephi, Eoborus fusiforme (Strophocheilidae; Gastrocopta mezzalirai, Gastrocopta itaboraiensis (Gastrocoptidae; Temesa magalhaesi (Clausiliidae. The species Strobilopsis mauryae was considered a synonym of Brasilennea arethusae; Bulimulus sommeri a synonym of Itaborahia lamegoi; and Vorticifex fluminensis a synonym of Eoborus sanctijosephi. Itaboraí Basin has the most ancient records of the families Orthalicidae, Gastrocoptidae, Ferussaciidae and Strophocheilidae. Moreover, the basin's records of Charopidae, Clausiliidae, Cerionidae, and Urocoptidae are among the most ancient in the world and, among these, those of Cerionidae, Clausiliidae and Urocoptidae deserve special attention since they are greatly removed from these families' current distribution. Additionally, Itaboraí has the most ancient records for the genera Austrodiscus, Brachypodella, Bulimulus, Cecilioides, Cyclodontina, Eoborus, Gastrocopta, Leiostracus, Plagiodontes and Temesa. There are three endemic genera in the basin: Brasilennea, Cortana and Itaborahia. Further discussion on paleobiogeography and evolution of this paleofauna is also provided.Os calc

  3. Evaluation of temporal, seasonal and geographic stability of the molluscicidal property of Euphorbia splendens latex Avaliação da estabilidade temporal, estacional e geográfica da ação moluscicida do latex da Euphorbia splendens

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    Virginia Torres Schall

    1992-06-01

    Full Text Available Laboratory tests with aqueous solutions of Euphorbia splendens var. hislopii latex have demonstrated seasonal stability of the molluscicidal principle, with LD90 values of 1.14 ppm (spring, 1.02 ppm (fall, 1.09 ppm (winter, and 1.07 ppm (summer that have been determined against Biomphalaria tenagophila in the field. Assays on latex collected in Belo Horizonte and Recife yielded LD90 values similar to those obtained with the reference substance collected in Rio de Janeiro (Ilha do Governador, demonstrating geographic stability of the molluscicidal effect. The molluscicidal action of aqueous dilutions of the latex in natura, centrifuged (precipitate and lyophilized, was stable for up to 124 days at room temperature (in natura and for up to 736 days in a common refrigerator at 10 to 12ºC (lyophilized product. A 5.0 ppm solution is 100% lethal for snails up to 13 days after preparation, the effect being gradually lost to almost total inactivity by the 30th day. This observation indicated that the active principle is instable. These properties together with the wide distribution of the plant, its resistance and adaptation to the tropical climate, its easy cultivation and the easy obtention of latex and preparation of the molluscicidal solution, make this a promising material for large-scale use in the control of schistosomiasisTestes de laboratório com soluções aquosas do látex da Euphorbia splendens var. hislopii demonstraram uma estabilidade estacional da atividade moluscicida do produto coletado na Ilha do Governador - RJ, encontrando-se as seguintes DL90: 1,14 ppm (primavera; 1,02 ppm (outono; 1,09 ppm (inverno e 1,07 ppm (verão sobre Biomphalaria tenagophila de campo. Ensaios com o látex da planta coletado em Belo Horizonte e Recife, identificaram DL90 semelhantes aos da substância de referência coletada no Rio, demonstrando uma estabilidade geográfica do efeito moluscicida. Usando diluições aquosas do latex in natura, centrifugado

  4. On the Ultrastructure and Function of Rhogocytes from the Pond Snail Lymnaea stagnalis.

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    Maria Kokkinopoulou

    Full Text Available Rhogocytes, also termed "pore cells", occur as solitary or clustered cells in the connective tissue of gastropod molluscs. Rhogocytes possess an enveloping lamina of extracellular matrix and enigmatic extracellular lacunae bridged by cytoplasmic bars that form 20 nm diaphragmatic slits likely to act as a molecular sieve. Recent papers highlight the embryogenesis and ultrastructure of these cells, and their role in heavy metal detoxification. Rhogocytes are the site of hemocyanin or hemoglobin biosynthesis in gastropods. Based on electron microscopy, we recently proposed a possible pathway of hemoglobin exocytosis through the slit apparatus, and provided molecular evidence of a common phylogenetic origin of molluscan rhogocytes, insect nephrocytes and vertebrate podocytes. However, the previously proposed secretion mode of the respiratory proteins into the hemolymph is still rather hypothetical, and the possible role of rhogocytes in detoxification requires additional data. Although our previous study on rhogocytes of the red-blooded (hemoglobin-containing freshwater snail Biomphalaria glabrata provided much new information, a disadvantage was that the hemoglobin molecules were not unequivocally defined in the electron microscope. This made it difficult to trace the exocytosis pathway of this protein. Therefore, we have now performed a similar study on the rhogocytes of the blue-blooded (hemocyanin-containing freshwater snail Lymnaea stagnalis. The intracellular hemocyanin could be identified in the electron microscope, either as individual molecules or as pseudo-crystalline arrays. Based on 3D-electron microscopy, and supplemented by in situ hybridization, immunocytochemistry and stress response experiments, we provide here additional details on the structure and hemocyanin biosynthesis of rhogocytes, and on their response in animals under cadmium and starvation stress. Moreover, we present an advanced model on the release of synthesized

  5. Private selective sweeps identified from next-generation pool-sequencing reveal convergent pathways under selection in two inbred Schistosoma mansoni strains.

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    Julie A J Clément

    Full Text Available BACKGROUND: The trematode flatworms of the genus Schistosoma, the causative agents of schistosomiasis, are among the most prevalent parasites in humans, affecting more than 200 million people worldwide. In this study, we focused on two well-characterized strains of S. mansoni, to explore signatures of selection. Both strains are highly inbred and exhibit differences in life history traits, in particular in their compatibility with the intermediate host Biomphalaria glabrata. METHODOLOGY/PRINCIPAL FINDINGS: We performed high throughput sequencing of DNA from pools of individuals of each strain using Illumina technology and identified single nucleotide polymorphisms (SNP and copy number variations (CNV. In total, 708,898 SNPs were identified and roughly 2,000 CNVs. The SNPs revealed low nucleotide diversity (π = 2 × 10(-4 within each strain and a high differentiation level (Fst = 0.73 between them. Based on a recently developed in-silico approach, we further detected 12 and 19 private (i.e. specific non-overlapping selective sweeps among the 121 and 151 sweeps found in total for each strain. CONCLUSIONS/SIGNIFICANCE: Functional annotation of transcripts lying in the private selective sweeps revealed specific selection for functions related to parasitic interaction (e.g. cell-cell adhesion or redox reactions. Despite high differentiation between strains, we identified evolutionary convergence of genes related to proteolysis, known as a key virulence factor and a potential target of drug and vaccine development. Our data show that pool-sequencing can be used for the detection of selective sweeps in parasite populations and enables one to identify biological functions under selection.

  6. Suscetibilidade aos agentes quimioterápicos de isolados de Schistosoma mansoni oriundos de pacientes tratados com oxamniquine e praziquantel e não curados

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    Neusa Araújo

    1996-10-01

    Full Text Available Foram estudados dez isolados de Schistosoma mansoni provenientes de pacientes residentes em Itaquara, Bahia, Brasil, tratados com oxamniquine eposteriormente com praziquantel, e ainda assim não curados. Caramujos (Biomphalaria glabrataj foram expostos a miracídios provenientes das fezes dos pacientes. Cercãrías eliminadas por estes caramujos e por moluscos coletados no peridomicílio dos pacientes foram utilizadas para infecção experimental de camundongos albinos. Os animais infectados foram tratados em dose única, via oral, com oxamniquine (25, 50 e 100 mg/kg ou praziquantel (100, 200 e 400mg/kg. Foram realizados estudos de análise e comparação de DNA de cercãrías de S. mansoni eliminadas pelos caramujos e de vermes adultos recolhidos de camundongos infectados experimentalmente com os isolados dos 10 pacientes e ainda de cercãrías de S. mansoni eliminadas por moluscos naturalmente infectados coletados em Itaquara. A cepa LE (mantida rotineiramente no laboratório foi usada como padrão de comparação da resposta aos agentes esquistossomicidas administrados. As respostas terapêuticas foram significativamente diferentes entre alguns dos isolados embora não fosse possível caracterizar nenhum como resistente. A análise dos perfis de amplificação de DNA nas cercãrías e nos vermes adultos dos isolados de S. mansoni demonstrou baixo grau de variabilidade indicando que estes são geneticamente próximos e revelando a ausência de rearranjos globais dentro dos genomas.

  7. Urinary Schistosomiasis in Urban and Semi-Urban Communities in South-Eastern Nigeria

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    Ogochukwu Caroline Okeke

    2013-09-01

    Full Text Available Background: In view of the massive rural-to-urban migration in Nigeria, investiga­tions on transmission of urinary schistosomiasis were carried out in ur­ban and semi-urban communities in Nike Lake area of Enugu State, Nigeria.Methods: Urine samples of school children were tested for micro-haematuria using reagent strips followed by microscopic examination for Schistosoma haemato­bium eggs. Water contact sites were also identified and sampled for snails.Results: The overall prevalence of S. haematobium eggs in school children was 4.64%. The mean intensity of infection was 1.14 + 0.41 eggs/10ml urine. Males had insignificantly higher prevalence and intensity of S. haematobium infec­tion than females. The youngest age group (4-7 years had no infection. The preva­lence of micro-haematuria (6.2% was higher than that of microscopy, and this correlated positively with prevalence (r=0.65, P < 0.01 and intensity (r=0.50, P < 0.01 of the infection. Potential intermediate host of human shistosome collected were: Bulinus globosus, B. senegalensis and Biomphalaria pfeifferi. How­ever, only B. globosus shed cercariae of S. haematobium, with a snail infection rate of 0.73%. Transmission was in the dry season coinciding with the drying of wells.Conclusion: The results revealed that urinary schistosomiasis is prevalent, and that B. globosus and not B. truncatus as previously reported is the main interme­diate host of urinary schistosomiasis in this part of Enugu State

  8. Molecular assessment of trematode co-infection and intraspecific competition in molluscan intermediate hosts.

    Science.gov (United States)

    Thiele, Elizabeth A; Minchella, Dennis J

    2013-01-01

    In natural populations of the human parasite Schistosoma mansoni, parasite distribution among snail intermediate hosts is generally overdispersed, such that a small proportion of hosts harbor the majority of parasite genotypes. Within these few infected snails, researchers have found that it can be common for hosts to harbor multiple parasite genotypes, creating circumstances in which co-infecting parasites are faced with potential competition over limited host resources. Much theoretical modeling has focused on parasite competition, especially regarding the influence of co-infection on parasite exploitation strategy evolution. However, particularly in the case of intra-molluscan intermediate stages, empirical investigations of parasite-parasite competition have often hinged on the untested assumption that co-exposure produces co-infection. That is, infected hosts exposed to multiple strains have been assumed to harbor multiple strains, regardless of the true nature of the infection outcome. Here we describe a real-time quantitative PCR method to distinguish the conditions of multiple- versus single-strain infection, as well as quantify the relative larval output of co-infecting strains. We applied the method to an empirical investigation of intraspecific parasite competition between S. mansoni strains within the intermediate snail host Biomphalaria glabrata, assessing co-exposure's effects on parasite infectivity and productivity and the concomitant effects on host fitness. Overall, there was no effect of parasite co-infection on snail life history traits relative to single-strain infection. Parasite infectivity significantly increased as a result of increasing overall miracidial dose, rather than co-exposure, though strain-specific productivity was significantly reduced in co-infections in manner consistent with resource competition. Moreover, we show that less than half of infected, co-exposed hosts had patent co-infections and demonstrate the utility of this

  9. Distribution and abundance of schistosomiasis and fascioliasis host snails along the Mara River in Kenya and Tanzania.

    Science.gov (United States)

    Dida, Gabriel O; Gelder, Frank B; Anyona, Douglas N; Matano, Ally-Said; Abuom, Paul O; Adoka, Samson O; Ouma, Collins; Kanangire, Canisius K; Owuor, Phillip O; Ofulla, Ayub V O

    2014-01-01

    We purposively selected 39 sampling sites along the Mara River and its two perennial tributaries of Amala and Nyangores and sampled snails. In addition, water physicochemical parameters (temperature, turbidity, dissolved oxygen, conductivity, alkalinity, salinity and pH) were taken to establish their influence on the snail abundance and habitat preference. Out of the 39 sites sampled, 10 (25.6%) had snails. The snail species encountered included Biomphalaria pfeifferi Krauss - the intermediate host of Schistosoma mansoni Sambon, Bulinus africanus - the intermediate host of Schistosoma haematobium, and Lymnaea natalensis Krauss - the intermediate host of both Fasciola gigantica and F. hepatica Cobbold. Ceratophallus spp., a non-vector snail was also encountered. Most (61.0%) of the snails were encountered in streamside pools. Schistosomiasis-transmitting host snails, B. pfeifferi and B. africanus, were fewer than fascioliasis-transmitting Lymnaea species. All the four different snail species were found to be attached to different aquatic weeds, with B. pfeifferi accounting for over half (61.1%) of the snails attached to the sedge, followed by B. africanus and Lymnaea spp., accounting for 22.2 and 16.7%, respectively. Ceratophallus spp. were non-existent in sedge. The results from this preliminary study show that snails intermediate hosts of schistosomiasis and fascioliasis exists in different habitats, in few areas along the Mara River, though their densities are still low to have any noticeable impacts on disease transmission in case they are infected. The mere presence of the vector snails in these focal regions calls for their immediate control and institution of proper regulations, management, and education among the locals that can help curtail the spread of the snails and also schistosomiasis and fascioliasis within the Mara River basin.

  10. Deep mRNA sequencing of the Tritonia diomedea brain transcriptome provides access to gene homologues for neuronal excitability, synaptic transmission and peptidergic signalling.

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    Adriano Senatore

    Full Text Available The sea slug Tritonia diomedea (Mollusca, Gastropoda, Nudibranchia, has a simple and highly accessible nervous system, making it useful for studying neuronal and synaptic mechanisms underlying behavior. Although many important contributions have been made using Tritonia, until now, a lack of genetic information has impeded exploration at the molecular level.We performed Illumina sequencing of central nervous system mRNAs from Tritonia, generating 133.1 million 100 base pair, paired-end reads. De novo reconstruction of the RNA-Seq data yielded a total of 185,546 contigs, which partitioned into 123,154 non-redundant gene clusters (unigenes. BLAST comparison with RefSeq and Swiss-Prot protein databases, as well as mRNA data from other invertebrates (gastropod molluscs: Aplysia californica, Lymnaea stagnalis and Biomphalaria glabrata; cnidarian: Nematostella vectensis revealed that up to 76,292 unigenes in the Tritonia transcriptome have putative homologues in other databases, 18,246 of which are below a more stringent E-value cut-off of 1x10-6. In silico prediction of secreted proteins from the Tritonia transcriptome shotgun assembly (TSA produced a database of 579 unique sequences of secreted proteins, which also exhibited markedly higher expression levels compared to other genes in the TSA.Our efforts greatly expand the availability of gene sequences available for Tritonia diomedea. We were able to extract full length protein sequences for most queried genes, including those involved in electrical excitability, synaptic vesicle release and neurotransmission, thus confirming that the transcriptome will serve as a useful tool for probing the molecular correlates of behavior in this species. We also generated a neurosecretome database that will serve as a useful tool for probing peptidergic signalling systems in the Tritonia brain.

  11. DETECTION OF IgM ANTIBODIES TO Schistosoma mansoni GUT-ASSOCIATED ANTIGENS FOR THE STUDY OF THE DYNAMICS OF SCHISTOSOMIASIS TRANSMISSION IN AN ENDEMIC AREA WITH LOW WORM BURDEN

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    KANAMURA Herminia Y.

    1998-01-01

    Full Text Available For a period of 2 years, five follow-up measures of prevalence and incidence rates were estimated in a prospective study of S. mansoni infection in a group of schoolchildren who were living in a rural area of the Municipality of Itariri (São Paulo, Brazil, where schistosomiasis is transmitted by Biomphalaria tenagophila. Infection was determined by the examination of three Kato-Katz stool slides, and the parasitological findings were analyzed in comparison to serological data. In the five surveys, carried out at 6-month intervals (March-April and September-October, the prevalences were, respectively, 8.6, 6.8, 9.9, 5.8 and 17.2% by the Kato-Katz, and 56.5, 52.6, 60.8, 53.5 and 70.1% by the immunofluorescence test (IFT. Geometric mean egg counts were low: 57.8, 33.0, 35.6, 47.3 and 40.9 eggs per gram of feces, respectively. Of the total of 299 schoolchildren, who submitted five blood samples at 6-month intervals, one for each survey, 40% were IFT-positive throughout the study, and 22% were IFT-negative in all five surveys. Seroconversion from IFT negative to positive, indicating newly acquired S. mansoni infection, was observed more frequently in surveys carried out during March-April (after Summer holidays, than during September-October. Seasonal trends were not statistically significant for detection of S. mansoni eggs in stool. The results indicate that the use of IgM-IFT is superior to parasitological methods for detection of incidence of S. mansoni infection in areas with low worm burden.

  12. Tetrapleura tetraptera: molluscicidal activity and chemical constituents.

    Science.gov (United States)

    Aladesanmi, Adetunji J

    2006-08-28

    Tetrapleura tetraptera (Schumach. And Thonn) Taub, Mimosaceae, commonly known as Aridan (fruit), A single stemmed, robust, perennial tree of about 30 m. It has a grey/brown, smooth/rough bark with glabrous yound branchlets. The flower is yellow/pink and racemes white the fruit has dark brown, four winged pods 12-25 x 3.5-6.5 cm. It is generally found in the lowland forest of tropical Africa. The fruit consists of a fleshy pulp with small, brownish-black seeds. The fruit possesses a fragrant, characteristically pungent aromatic odour, which is attributed to its insect repellent property. It is used as spices and aroma (exotic tropical scents) and fish poisoning. It is one of the molluscicidal medicinal plants of Nigeria, also useful in the management of convulsions, leprosy, inflammation and/or rheumatoid pains. The documented biological and-or pharmacological activities are found to be molluscicidal, cardio-vascular, neuromuscular, hypotensive, anti-convulsant, trypanocidal, hirudinicidal, schistosomiasis control, anti-ulcerative, ectoxicity, anti-inflammatory, hypoglycaemic, anti-microbial, emulsifying property, birth control, food value and the control of intestinal parasites. Activity-guided fractionation of the methanol extract of the fruits of T. tetraptera led to the isolation of a saponin glycoside with an oleanolic acid aglycone, a monodesmosidic diglycoside of the rare sapogenin 27-hydroxyolean-12 (13)-en-28-oic acid; echinocystic acid-3-0-sodium sulfate from the stembark, umbelliferone and ferulic acid from the leaves and branches respectively. Also isolated from the fruits were aridanin and three of its olean-12-en-28-oic acid derivatives. All the compounds isolated either from the fruits or other parts were found to exhibit strong molluscicidal properties against the schistosomiasis-transmitting snails Biomphalaria glabrata.

  13. Low-cost motility tracking system (LOCOMOTIS for time-lapse microscopy applications and cell visualisation.

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    Adam E Lynch

    Full Text Available Direct visualisation of cells for the purpose of studying their motility has typically required expensive microscopy equipment. However, recent advances in digital sensors mean that it is now possible to image cells for a fraction of the price of a standard microscope. Along with low-cost imaging there has also been a large increase in the availability of high quality, open-source analysis programs. In this study we describe the development and performance of an expandable cell motility system employing inexpensive, commercially available digital USB microscopes to image various cell types using time-lapse and perform tracking assays in proof-of-concept experiments. With this system we were able to measure and record three separate assays simultaneously on one personal computer using identical microscopes, and obtained tracking results comparable in quality to those from other studies that used standard, more expensive, equipment. The microscopes used in our system were capable of a maximum magnification of 413.6×. Although resolution was lower than that of a standard inverted microscope we found this difference to be indistinguishable at the magnification chosen for cell tracking experiments (206.8×. In preliminary cell culture experiments using our system, velocities (mean µm/min ± SE of 0.81 ± 0.01 (Biomphalaria glabrata hemocytes on uncoated plates, 1.17 ± 0.004 (MDA-MB-231 breast cancer cells, 1.24 ± 0.006 (SC5 mouse Sertoli cells and 2.21 ± 0.01 (B. glabrata hemocytes on Poly-L-Lysine coated plates, were measured and are consistent with previous reports. We believe that this system, coupled with open-source analysis software, demonstrates that higher throughput time-lapse imaging of cells for the purpose of studying motility can be an affordable option for all researchers.

  14. Low-cost motility tracking system (LOCOMOTIS) for time-lapse microscopy applications and cell visualisation.

    Science.gov (United States)

    Lynch, Adam E; Triajianto, Junian; Routledge, Edwin

    2014-01-01

    Direct visualisation of cells for the purpose of studying their motility has typically required expensive microscopy equipment. However, recent advances in digital sensors mean that it is now possible to image cells for a fraction of the price of a standard microscope. Along with low-cost imaging there has also been a large increase in the availability of high quality, open-source analysis programs. In this study we describe the development and performance of an expandable cell motility system employing inexpensive, commercially available digital USB microscopes to image various cell types using time-lapse and perform tracking assays in proof-of-concept experiments. With this system we were able to measure and record three separate assays simultaneously on one personal computer using identical microscopes, and obtained tracking results comparable in quality to those from other studies that used standard, more expensive, equipment. The microscopes used in our system were capable of a maximum magnification of 413.6×. Although resolution was lower than that of a standard inverted microscope we found this difference to be indistinguishable at the magnification chosen for cell tracking experiments (206.8×). In preliminary cell culture experiments using our system, velocities (mean µm/min ± SE) of 0.81 ± 0.01 (Biomphalaria glabrata hemocytes on uncoated plates), 1.17 ± 0.004 (MDA-MB-231 breast cancer cells), 1.24 ± 0.006 (SC5 mouse Sertoli cells) and 2.21 ± 0.01 (B. glabrata hemocytes on Poly-L-Lysine coated plates), were measured and are consistent with previous reports. We believe that this system, coupled with open-source analysis software, demonstrates that higher throughput time-lapse imaging of cells for the purpose of studying motility can be an affordable option for all researchers.

  15. The Last Fifteen Years of Schistosomiasis in Venezuela: Features and Evolution

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    Alarcón de Noya Belkisyolé

    1999-01-01

    Full Text Available Control of schistosomiasis in Venezuela has been a topic of major interest and controversy among the metaxenic parasitosis. A small area of transmission of approximately 15,000 km2 was thought to be eradicated some years ago. However, some epidemiological characteristics of our transmission area have limited the success on the way toward eradication. Since 1945, when the Schistosomiasis Control Program started, the prevalence in the endemic area has decreased from 14% in 1943 to 1.4% in 1996. Until 1982, the surveillance of active cases was based on massive stool examination. Since then, the Schistosomiasis Research Group (SRG recommended the additional use of serologic tests in the Control Program and the selective or massive chemotherapy depending on serological and parasitological prevalence of each community. At present, the real prevalence is underestimated due to the fact that approximately 80% of the individuals eliminate less than 100 eggs/g of feces. Those persons could be responsible for the maintenance of the foci going on and therefore limiting the impact of the control measures. Efforts of the SRG are being oriented toward improvement of immunodiagnostic tests by using defined antigens (enzymes and chemically synthesized peptides, derived from relevant molecules of the parasite, either for antibodies or antigens search. On the other hand, introduction of snail competitors has been a biological weapon in the control of the intermediate host in certain areas. However, the recent reinfestation of water courses by Biomphalaria glabrata, the increased prevalence in some areas, together with important administrative changes at the Control Program of the Minister of Health, have arisen new questions and doubts, challenging the eradication strategy proposed during the last decade.

  16. Schistosoma mansoni mucin gene (SmPoMuc expression: epigenetic control to shape adaptation to a new host.

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    Cecile Perrin

    Full Text Available The digenetic trematode Schistosoma mansoni is a human parasite that uses the mollusc Biomphalaria glabrata as intermediate host. Specific S. mansoni strains can infect efficiently only certain B. glabrata strains (compatible strain while others are incompatible. Strain-specific differences in transcription of a conserved family of polymorphic mucins (SmPoMucs in S. mansoni are the principle determinants for this compatibility. In the present study, we investigated the bases of the control of SmPoMuc expression that evolved to evade B. glabrata diversified antigen recognition molecules. We compared the DNA sequences and chromatin structure of SmPoMuc promoters of two S. mansoni strains that are either compatible (C or incompatible (IC with a reference snail host. We reveal that although sequence differences are observed between active promoter regions of SmPoMuc genes, the sequences of the promoters are not diverse and are conserved between IC and C strains, suggesting that genetics alone cannot explain the evolution of compatibility polymorphism. In contrast, promoters carry epigenetic marks that are significantly different between the C and IC strains. Moreover, we show that modifications of the structure of the chromatin of the parasite modify transcription of SmPoMuc in the IC strain compared to the C strain and correlate with the presence of additional combinations of SmPoMuc transcripts only observed in the IC phenotype. Our results indicate that transcription polymorphism of a gene family that is responsible for an important adaptive trait of the parasite is epigenetically encoded. These strain-specific epigenetic marks are heritable, but can change while the underlying genetic information remains stable. This suggests that epigenetic changes may be important for the early steps in the adaptation of pathogens to new hosts, and might be an initial step in adaptive evolution in general.

  17. Reconstructing Colonization Dynamics of the Human Parasite Schistosoma mansoni following Anthropogenic Environmental Changes in Northwest Senegal.

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    Frederik Van den Broeck

    2015-08-01

    Full Text Available Anthropogenic environmental changes may lead to ecosystem destabilization and the unintentional colonization of new habitats by parasite populations. A remarkable example is the outbreak of intestinal schistosomiasis in Northwest Senegal following the construction of two dams in the '80s. While many studies have investigated the epidemiological, immunological and geographical patterns of Schistosoma mansoni infections in this region, little is known about its colonization history.Parasites were collected at several time points after the disease outbreak and genotyped using a 420 bp fragment of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1 and nine nuclear DNA microsatellite markers. Phylogeographic and population genetic analyses revealed the presence of (i many genetically different haplotypes at the non-recombining mitochondrial marker and (ii one homogenous S. mansoni genetic group at the recombining microsatellite markers. These results suggest that the S. mansoni population in Northwest Senegal was triggered by intraspecific hybridization (i.e. admixture between parasites that were introduced from different regions. This would comply with the extensive immigration of infected seasonal agricultural workers from neighboring regions in Senegal, Mauritania and Mali. The spatial and temporal stability of the established S. mansoni population suggests a swift local adaptation of the parasite to the local intermediate snail host Biomphalaria pfeifferi at the onset of the epidemic.Our results show that S. mansoni parasites are very successful in colonizing new areas without significant loss of genetic diversity. Maintaining high levels of diversity guarantees the adaptive potential of these parasites to cope with selective pressures such as drug treatment, which might complicate efforts to control the disease.

  18. Histopatologia da esquistossomose mansoni em fígado de Mus musculus infectado por amostras humanas de fase aguda e crônica da periferia de Belo Horizonte, Minas Gerais

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    Amélia Dulce Vilela de Carvalho

    1986-06-01

    Full Text Available Exemplares de Biomphalaria glabrataforam infectados com miracídios obtidos de ovos de Schistosoma mansoni, encontrados em fezes de indivíduos de 7 a 18 anos, da região de Lagoa da Pampulha, Belo Horizonte, MG. Os pacientes de fase aguda se infectaram em uma primeira visita ao foco. Os da fase crônica eram moradores próximos aos focos. Para cada caso clínico, isolou-se a respectiva amostra do parasita. Foram infectados pela cauda 55 camundongos fêmeas com 70 ± 10 cercárias. Cortes histológicos de fígados, corados por HE, tricrômico de Gomori, impregnação metálica pela prata, e PAS foram observados à microscopia óptica. Não houve diferenças estatísticas em relação às médias das mensurações dos diâmetros dos granulomas referentes às amostras e datas de sacrifícios. Os granulomas apresentaram fase exsudativa do tipo Ha (reação de inflamação mista e IIIa (granuloma com células epitelióides. Com amostras de pacientes em fase aguda o padrão predominante foi a Ha na 7ª semana. Na 10.ª semana predominaram granulomas do tipo IIIa. Nas amostras de pacientes em fase crônica, verificou-se uma mescla de granulomas do tipo Ha e IIIa na 7ª semana. Na 10ª semana predominou o tipo IIIa. Alguns aspectos histopatológicos de fígados foram descritos e comparados com aqueles existentes na literatura.

  19. Experimental evaluation of Candonocypris novaezelandiae(Crustacea:Ostracoda) in the biocontrol of Schistosomiasis mansoni transmission

    Institute of Scientific and Technical Information of China (English)

    Fouad; Yousif; Sherif; Hafez; Samia; El; Bardicy; Menerva; Tadros; Hoda; Abu; Taleb

    2013-01-01

    Objective:To test Candonocypris novaezelandiae(Baird)(C.novaezelandiae),sub-class Ostracoda,obtained from the Nile,Egypt for its predatory activity on snail,Biomphalaria alexandrina(B.alexandrina),intermediate host of Schistosoma mansoni(S.mansoni)and on the free-living larval stages of this parasite(miracidia and cercariae).Methods:The predatory activity of C.novaezelandiae was determined on B.alexandrina snail(several densities of eggs,newly hatched and juveniles).This activity was also determined on S.mansoni miracidia and cercariae using different volumes of water and different numbers of larvae.C.novaezelandiae was also tested for its effect on infection of snails and on the cercarial production.Results:C.novaezelandiae was found to feed on the eggs,newly hatched and juvenile snails,but with significant reduction in the consumption in the presence of other diet like the blue green algae(Nostoc muscorum).This ostracod also showed considerable predatory activity on the free-living larval stages of S.mansoni which was affected by certain environmental factors such as volume of water,density of C.novaezelandiae and number of larvae of the parasite.Conclusions:The presence of this ostracod in the aquatic habitat led to significant reduction of snail population,infection rate of snails with schistosme miracidia as well as of cercarial production from the infected snails.This may suggest that introducing C.novaezelandiae into the habitat at schistosome riskv sites could suppress the transmission of the disease.

  20. Molecular characterisation of intermediate snail hosts and the search for resistance genes

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    David Rollinson

    1998-01-01

    Full Text Available The relationship between schistosomes and their intermediate hosts is an extremely intricate one with strains and species of the parasite depending on particular species of snail, which in turn may vary in their susceptibility to the parasites. In order to gain a better understanding of the epidemiology of the disease we have been investigating the use of molecular markers for snail identification and for studying host-parasite relationships. In this paper we will draw on examples concerning schistosomiasis in West and East Africa to illustrate how a molecular analysis can be used as part of a "total evidence" approach to characterisation of Bulinus species and provide insights into parasite transmission. Particular emphasis is given to ribosomal RNA genes (rRNA, random amplified polymorphic DNA (RAPDs and the mitochondrial gene cytochrome oxidase I (COI. Snails resistant to infection occur naturally and there is a genetic basis for this resistance. In Biomphalaria glabrata resistance to Schistosoma mansoni is known to be a polygenic trait and we have initiated a preliminary search for snail genomic regions linked to, or involved in, resistance by using a RAPD based approach in conjunction with progeny pooling methods. We are currently characterising a variety of STSs (sequence tagged sites associated with resistance. These can be used for local linkage and interval mapping to define genomic regions associated with the resistance trait. The development of such markers into simple dot-blot or specific PCR-based assays may have a direct and practical application for the identification of resistant snails in natural populations.

  1. The effects of the herbicide atrazine on freshwater snails.

    Science.gov (United States)

    Gustafson, Kyle D; Belden, Jason B; Bolek, Matthew G

    2015-07-01

    Atrazine has been shown to affect freshwater snails from the subcellular to community level. However, most studies have used different snail species, methods, endpoints, and atrazine exposure concentrations, resulting in some conflicting results and limiting our understanding. The goal of this study was to address these concerns by (1) investigating the acute and chronic effects of atrazine on four species of freshwater snails (Biomphalaria glabrata, Helisoma trivolvis, Physa acuta, and Stagnicola elodes) using the same methods, endpoints, and concentrations, and (2) summarizing the current literature pertaining to the effects of atrazine on freshwater snails. We conducted a 48 h acute toxicity test with an atrazine concentration higher than what typically occurs in aquatic environments (1000 µg/L). Additionally, we exposed snails to environmentally relevant atrazine concentrations (0, 0.3, 3, and 30 µg/L) for 28 days and assessed snail survival, growth, and reproduction. We also summarized all known literature pertaining to atrazine effects on freshwater snails. The literature summary suggests snails are often affected by environmentally relevant atrazine concentrations at the subcellular and cellular levels. These effects are typically not transitive to effects on survival, growth, or reproduction at the same concentrations. Our acute exposures corroborate the general trend of no direct effect on snail populations as atrazine did not directly affect the survival of any of the four snail species. Similarly, environmentally relevant concentrations did not significantly affect the survival, growth, or reproduction of any snail species. These results indicate that, in the absence of other possible stressors, the direct effects of environmentally relevant atrazine concentrations may not be realized at the snail population level.

  2. Specific versus non-specific immune responses in an invertebrate species evidenced by a comparative de novo sequencing study.

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    Emeline Deleury

    Full Text Available Our present understanding of the functioning and evolutionary history of invertebrate innate immunity derives mostly from studies on a few model species belonging to ecdysozoa. In particular, the characterization of signaling pathways dedicated to specific responses towards fungi and Gram-positive or Gram-negative bacteria in Drosophila melanogaster challenged our original view of a non-specific immunity in invertebrates. However, much remains to be elucidated from lophotrochozoan species. To investigate the global specificity of the immune response in the fresh-water snail Biomphalaria glabrata, we used massive Illumina sequencing of 5'-end cDNAs to compare expression profiles after challenge by Gram-positive or Gram-negative bacteria or after a yeast challenge. 5'-end cDNA sequencing of the libraries yielded over 12 millions high quality reads. To link these short reads to expressed genes, we prepared a reference transcriptomic database through automatic assembly and annotation of the 758,510 redundant sequences (ESTs, mRNAs of B. glabrata available in public databases. Computational analysis of Illumina reads followed by multivariate analyses allowed identification of 1685 candidate transcripts differentially expressed after an immune challenge, with a two fold ratio between transcripts showing a challenge-specific expression versus a lower or non-specific differential expression. Differential expression has been validated using quantitative PCR for a subset of randomly selected candidates. Predicted functions of annotated candidates (approx. 700 unisequences belonged to a large extend to similar functional categories or protein types. This work significantly expands upon previous gene discovery and expression studies on B. glabrata and suggests that responses to various pathogens may involve similar immune processes or signaling pathways but different genes belonging to multigenic families. These results raise the question of the importance

  3. Susceptibility of 7 freshwater gastropod species in Zimbabwe to infection with Gastrodiscus aegyptiacus (Cobbold, 1876 Looss, 1896 : short communication

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    S. Mukaratirwa

    2004-06-01

    Full Text Available Gastrodiscosis outbreaks due to Gastrodiscus aegyptiacus were recorded in horses in the vicinity of Harare, Zimbabwe, in the absence of Bulinus forskalii, B. senegalensis and Cleopatra sp. which are considered to be the only intermediate host snails. This suggested the possibility of other snail species acting as intermediate hosts in the life cycle of the trematode. A study was carried out to determine the susceptibility of 7 freshwater snail species to infection with G. aegyptiacus. First generation (F-1 of 5 freshwater pulmonate snail species, Bulinus tropicus, Bulinus globosus, Biomphalaria pfeifferi, Helisoma dyuri and Physa acuta that were bred in the laboratory, and 2 prosobranch snail species, Melanoides tuberculata and Cleopatra sp. that were collected from the field were used in this study. Data pertaining to mortalities and cercariae shedding were recorded throughout the experimental period. The prosobranch snails, M. tuberculata and Cleopatra sp. were susceptible to G. aegyptiacus with a minimum prepatent period of 45 days and 54 days, respectively. Bulinus tropicus, P. acuta and H. duryi were susceptible as evidenced by the presence of different generations of rediae and mature cercariae on dissection at 59 days post-infection although attempts to induce the snails to shed from 28 days post-infection did not produce cercariae. Bulinus globosus and Bio. Pfeifferi were refractory to infection. The results revealed the ability of G. aegyptiacus to infect M. tuberculata, Cleopatara sp., B. tropicus, P. acuta and H. duryi under experimental conditions and this may explain the recorded outbreaks of gastrodiscosis in equine populations in Zimbabwe in the absence of the known intermediate hosts. Bulinus tropicus is considered as the most likely major intermediate host of G. aegyptiacus because of its wide distribution in Zimbabwe and is well adapted to a wide variety of environments.

  4. Habitat characteristics for different freshwater snail species as determined biologically through macroinvertebrate information.

    Science.gov (United States)

    El-Khayat, Hanaa M M; Mahmoud, Kadria M A; Mostafa, Bayomy B; Tantawy, Ahmad A; El-Deeb, Fatma A; Ragb, Fawzy M; Ismail, Nahed M; El-Said, Kalil M; Taleb, Hoda M Abu

    2011-12-01

    Macro-invertebrates including freshwater snails collected from 643 sites over 8 successive seasons among the River Nile, branches, main canals and certain drains in eight Egyptian Governorates. Thirteen snail species and one bivalve species were identified. The most distributed were Lanistus carinatus and Physa acuta while the most abundant were Cleopatra bulimoides and Physa acuta during the whole study. The sites that harbored each snail species in all the examined water-courses were grouped seasonally and their biological assessment was determined by their minimum and maximum total point similarity percentage to that of the corresponded reference site and mean of the total points. Habitats for most snail species attained minimum total point's similarity percentage less than 21% (very poor habitat) during autumn and winter then spring while during summer very poor habitat was harbored by only few snail species. P. acuta was the only survived snails in habitat which attained 0 as a minimum total point's similarity percentage during two seasons and L. carinatus and Succinea cleopatra during one season. With respect to medically important snails very poor sites constituted 23% of Biomphalaria alexandrina sites, 14% of Lymnaea natalensis and 9.4% of Bulinus truncatus sites. The studied macroinvertebrate matrices, total number of organisms, taxa richness, the Ephemeroptera, Plecoptera, and Trichoptera (EPT) index, ratio of EPT index to chironomidae, ratio of scraper to filtering collector, contribution of dominant macroinvertebrate major group, comparison revealed descending tolerances from B. alexanrina followed by L. natalensis then B. truncates, but Hilsenhoff Biotic Index (HBI) showed the same tolerance to organic pollution.

  5. Alguns dados sobre o comportamento parasitológico das linhagens humana e silvestre do Schistosoma mansoni, no Vale do Rio Paraíba do Sul, SP (Brasil Some data on the parasitological behaviour of human (H and wild (S strains of S. mansoni, in the Paraiba do Sul River Valley, State of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Othon de Carvalho Bastos

    1978-06-01

    Full Text Available Verificou-se ser elevada a percentagem de animais parasitados por S. mansoni em roedores silvestres, de diferentes gêneros e espécies, capturados no Vale do Rio Paraíba do Sul, SP, Brasil onde se encontram com freqüência, casos humanos de esquistossomose mansônica. A partir de fígados de roedores naturalmente infectados foram obtidos miracídios para o isolamento da linhagem silvestre (S. Para o isolamento da linhagem humana (H, foram utilizados miracídios procedentes de fezes de doentes comprovadamente autóctones do Vale do Rio Paraíba. Estudou-se, comparativamente, o comportamento das duas linhagens em B. tenagophila que é o hospedeiro intermediário natural na região e em camundongo albino, utilizado como hospedeiro definitivo. Verificou-se que: a taxa de mortalidade de B. tenagophila infectadas com a linhagem "S" não é, estatisticamente, diferente da dos moluscos utilizados para controle; é significativa a diferença entre a taxa de mortalidade verificada nos moluscos infectados com a linhagem "S" e com a linhagem "H", a qual é consideravelmente maior nos moluscos infectados com a linhagem "H"; nos camundongos infectados com a linhagem "H" verificou-se ser significativo o coeficiente de correlação entre o número de granulomas hepáticos e o de trematódeos adultos; nos camundongos infectados com a linhagem ''S" não houve possibilidade do estabelecimento de tal correleção.Human (H and wild (S Schistosoma mansoni strains were obtained; the H strain from eggs colected in human feces and the S strain having its source in livers of several species of wild rodents. Results of the behaviour of these strains in Biomphalaria tenagophila and in albino Mus musculus are exposed in this work, summarized as follows: the mortality rate, statistically, did not differ in the group of infected snails and in the group of control snails; however, the difference between the mortality rates in snails infected with "H" strain and with "S

  6. Potential impacts of damming the Juba Valley, western Somalia: Insights from geomorphology and alluvial history

    Science.gov (United States)

    Williams, Martin

    2014-05-01

    In 1988 plans were well advanced to dam the Juba River in western Somalia. The aims of the Baardheere Dam Project were to generate hydroelectric power for the capital Mogadishu, and to provide water for irrigation in the Juba Valley. A reconnaissance survey on foot along 500 km of the river upstream of the proposed dam site at Baardheere and detailed geomorphic mapping from air photos provided a basis for reconstructing the late Quaternary alluvial history of the river and for assessing the potential impact of the proposed dam. The Juba River rises in the Ethiopian Highlands and is the only river in Somalia that flows to the sea. Its history reflects climatic events in Ethiopia, where the Rift Valley lakes were very low during the LGM (21±2 ka), and high for about 5, 000 years before and after then. Cave deposits in Somalia indicate wetter conditions at 13, 10, 7.5 and 1.5 ka. Alluvial terraces in the Juba Valley range in age from late Pleistocene to late Holocene but only attain a few metres above the present floodplain. This is because the dry tributary valleys contain limestone caves and fissures that divert any high flows from the parent river underground, a process not known when the project was first approved. The oldest preserved terrace was cemented by calcrete by 40 ka. Alluvial gravels were deposited at the outlet of dry tributary valleys during times of episodic high-energy flow between 26 ka and 28 ka. Finely laminated shelly sands accumulated at 10 ka to form the 5 m terrace. The 2 m terrace was laid down 3.2 ka ago as a slackwater deposit. The lack of high-level alluvial terraces raises doubts over plans to dam the river, since rapid leakage would occur from side valleys and the reservoir would not attain the height needed to generate hydroelectric power. It would submerge all existing arable land along the river. Finally, the presence in the late Holocene alluvium of the sub-fossil gastropods Bulinus truncatus and Biomphalaria pfeifferi, which are

  7. Epidemiology and control of intestinal schistosomiasis on the Sesse Islands, Uganda: integrating malacology and parasitology to tailor local treatment recommendations

    Directory of Open Access Journals (Sweden)

    Fenwick Alan

    2010-07-01

    Full Text Available Abstract Background Intestinal schistosomiasis is often widespread among the populations living around Lake Victoria and on its islands. The Sesse Island group (containing some 84 islands, however, is typically assumed to be a low prevalence zone, with limited transmission, but has never been surveyed in detail. Here, we present a rapid mapping assessment, bringing together snail and parasite information, at 23 sites for the presence of intermediate host snails and at 61 sites for the prevalence of intestinal schistosomiasis in school-aged children (N = 905. Two different diagnostic tools were used and compared at 45 of these sites: Kato-Katz thick faecal smears and circulating cathodic antigen (CCA urine dipsticks. Results Biomphalaria snails were found at 11 sites but in low numbers; none was found shedding schistosome cercariae. At 22 out of the 45 sites, local prevalence by urine and/or stool diagnostics was in excess of 50%, although mean prevalence of intestinal schistosomiasis overall was 34.6% (95% confidence intervals (CI = 31.0-38.3% by Kato-Katz and 46.5% (95% CI = 42.7-50.4% by CCA if 'trace' reactions were considered infection-positive (if considered infection-negative, mean prevalence was 28.1% (95% CI = 24.7-31.7%. Diagnostic congruence between CCA and Kato-Katz was poor and significant discordance in estimated prevalence by location was found, with each often inferring different mass drug administration regimes. Conclusions Accurate estimation of schistosome prevalence is important for determining present and future treatment needs with praziquantel; the wide range of schistosome prevalence across the Sesse Island group requires a treatment regime largely tailored to each island. In high prevalence locations, further malacological sampling is required to confirm the extent of local transmission, especially on the northern islands within the group. The observation that different diagnostic tests can provide varying results in

  8. [Schistosomiasis endemic in Burkina Faso].

    Science.gov (United States)

    Poda, J N; Traoré, A; Sondo, B K

    2004-02-01

    Burkina Faso, through the works of many teams of the OCCGE based in Bobo-Dioulasso, has signi-ficant data on several tropical endemics of which schistosomiasis. With the complementary works, it appears to be possible to establish a distribution of the schistosomiasis which reveals its importance. It will be the first stage of the planned national control program. The parasitologic data-gathering which covers the period of 1951 to 2000, used all the standard techniques. It is about Kato-Kartz and MIF for the intestinal schistosomiasis, centrifugation, filtration, serology reagent strips, macroscopy of urines and echography of the urinary system for the urinary schistosomiasis. All the eleven medical areas of the country have many sites submitted to parasitologic investigation. As regard the distribution of the two parasites involved with man (Schistosoma haematobium and S. mansoni), the data of prevalence (1% to 100%) and their distribution confirm their endemicity and the focal transmission. S. mansoni is located in eight medical areas particularly in the South and the West. S. haematobium is present in all the eleven medical areas of the country. In hydraulic planning as Sourou where the prevalences went from 23% to 70% for S. haematobium and from 0% to 69% for S. mansoni between 1987 and 1998. The situation requires a continuous monitoring. The spatial distribution of the six species of intermediate hosts shows that Bulinus truncatus and B. senegalensis Soudano-Sahelian species are present in all the ecological zones. B. globosus and Biomphalaria pfeifferi meet preferentially in the southern half of the country which reinforces the observation according to which the 14th northern parallel is often considered as the limit of septentrional extension of these two species. The other species Bulinus forskalii and B umbilicatus could have preference areas. All the species show a certain affinity with a type of biotope. The rarity and temporary aquatic systems lead to a

  9. Ecology of larval mosquitoes, with special reference to Anopheles arabiensis (Diptera: Culcidae) in market-garden wells in urban Dakar, Senegal.

    Science.gov (United States)

    Robert, V; Awono-Ambene, H P; Thioulouse, J

    1998-11-01

    The urban area of Dakar, Senegal, contains > 5,000 market-garden wells that provide permanent sites for mosquito larvae, in particular Anopheles arabiensis Patton, the major vector of malaria. A study of the bioecology of mosquito larvae was conducted over 1 yr with a monthly visit to 48 of these wells. Overall, 9,589 larvae were collected of which 80.1% were Culicinae and 11.9% Anophelinae. Larvae from stages III and IV (n = 853) were identified to 10 species. An. arabiensis represented 86% of the anophelines collected and An. ziemanni Grunberg 14%. The most common Culicinae species included Aedeomyia africana Neveu-Lemaire, Culex quinquefasciatus Say, and Mimomyia splendens Theobald. Maximum anopheline abundance was observed at the end of the dry season in June, whereas maximum Culicinae abundance was observed at the end of the rainy season in September. Most wells (67%) did not harbor any An. arabiensis larvae and in the remaining 33% the larval abundance was low, averaging 0.54 larvae in stages III-IV per tray sample. To identify factors that determine the abundance of larvae in these wells, a co-inertia (multivariate) analysis was carried out to account for physicochemical variables (depth, turbidity, temperature, pH, conductivity, Na+, Cl-, HCO3-, CO3--, and NO3- concentrations) and biological variables (abundance of mosquito species, predators [e.g., fish, Dytiscidae, Notonectidae, odonates], molluscs [Bulinus and Biomphalaria], and surface plants [water lettuce, Lemna, and filamentous algae]). The co-inertia analysis indicated that the abundance of An. arabiensis was associated with Cx. quinquefasciatus and Cx. decens for the physiochemical data but was not associated with other mosquito species for floro-faunistic data. The conditions associated with abundant An. arabiensis were warm temperature (28-30 degrees C), clear and not too deep water (odonates), the presence of water lettuce, and an absence of Lemna. These results indicate that many contributing

  10. Efficacy of praziquantel and reinfection patterns in single and mixed infection foci for intestinal and urogenital schistosomiasis in Cameroon.

    Science.gov (United States)

    Tchuem Tchuenté, Louis-Albert; Momo, Sabine C; Stothard, J Russell; Rollinson, David

    2013-11-01

    northern settings, three species of Bulinus (intermediate host snail of S. haematobium) were collected; i.e. Bulinus truncatus, B. globosus and B. senegalensis, however, Biomphalaria pfeifferi (intermediate host snail of S. mansoni) was much rarer despite repeated and intensive searching and was suggestive of limited local transmission potential of S. mansoni during this time. While this study highlights that performance of PZQ was satisfactory in this region, with somewhat greater impact upon intestinal than urogenital schistosomiasis, the dynamics of local transmission are shown, however, to be complex.

  11. A municipal level approach to the management of schistosomiasis control in Peri-Peri, MG, Brazil Avaliação de um programa municipalizado de controle da esquistossomose em Peri-Peri, MG -Brasil

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    Pedro Coura Filho

    1992-12-01

    Full Text Available A schistosomiasis control program was implemented between 1974/87 in Peri-Peri,. MG (622 inhabitants. Molluscicide (niclosamide was applied at three monthly intervals in water sources with Biomphalaria glabrata, and individuals eliminating Schistosoma mansoni eggs in the feces were treated annually with oxamniquine. From 1974 to 1983 the control measures were undertaken by staff of the "René Rachou" Research Center FIOCRUZ (CPqRR, and from 1984 to 1987 these measures were included in the Capim Branco basic health network activities. During both periods, the prevalence, incidence, intensity of infection and hepatosplenic form as well as the number of infected snails decreased significantly. The prevalence decreased from 43.5 to 4.4%, the incidence from 19.0 to 2.9%, the overall intensity of S. mansoni from 281 to 87 and of the hepatosplenic form from 5.9 to 0.0%. The results obtained suggest that the municipal management of control measures was as effective as the vertical program conducted by CPqRR staff.Um programa de controle da esquistossomose foi desenvolvido em Peri-Peri, MG (município de Capim Branco entre 1974/87. Foi aplicado moluscicida em intervalos de 3 meses nas coleções hídricas da área e indivíduos eliminando ovos de Schistosoma mansoni nas fezes foram tratados anualmente com oxamniquine. De 1974 a 1983 as medidas de controle foram realizadas pela equipe do Centro de Pesquisas "René Rachou" -FIOCRUZ, e de 1984 a 1987 foram incluídas nas atividades da rede básica de saúde de Capim Branco. Durante ambos períodos, a prevalência, incidência e intensidade da infecção e forma hepatosplênica assim como o índice de caramujos infectados decresceram significativamente. A prevalência decresceu de 43,5 para 4,4 %, a incidência de 19,0 para 2,9%, a intensidade da infecção de 281 ovos por grama de fezes para 87 e a forma hepatoesplênica de 5,9 para 0,0%. Os resultados obtidos sugerem que a inclusão das medidas de controle

  12. Laboratory assessment of the molluscicidal and cercariacidal activities of Balanites aegyptiaca

    Institute of Scientific and Technical Information of China (English)

    Eshetu Molla; Mirutse Giday; Berhanu Erko

    2013-01-01

    Objective: To assess the molluscicidal and cercariacidal activities of aqueous extracts ofBalanites aegyptiaca (B. aegyptiaca) against Ethiopian Biomphalaria pfeifferi (B. pfeifferi), Lymnaea natalensis (L. natalensis) and Schistosoma mansoni (S. mansoni) cercariae. Methods:Extracts of seeds, endocarp, mesocarp, and fruit of B. aegyptiaca were tested for their activities against adult B. pfeifferi and L. natalensis. The cercariacidal activity of the seeds of the plant was also evaluated against S. mansoni. Bioassays were carried out following the methods recommended by WHO. Snail mortalities were compared between each plant part and snail species, and LC50 and LC90 values for the plant parts tested were computed. The cercariacidal activity of the plant was assessed by exposing the mice to the cercariae pre-exposed to aqueous extract of B. aegyptiaca seeds. Results:For the molluscicidal activities of seeds, endocarp, mesocarp and whole fruit, the LC50 values against B. pfeifferi were 56.32, 77.53, 65.51 and 66.63 mg/L, respectively, while the respective LC90 values were 77.70, 120.04, 89.50 and 97.55 mg/L. Similarly, the LC50 values for the seeds, endocarp, mesocarp and whole fruit against L. natalensis were 80.33, 92.61, 83.52 and 87.84 mg/L, respectively, while the respective LC90 values were 102.30, 138.21, 115.42 and 127.69 mg/L. B. pfeifferi were found to be more susceptible to B. aegyptiaca than L. natalensis. S. mansoni cercariae exposed to 15 mg/L of extract of seeds were incapable of infecting mice. The mean egg load of tissue was reduced in mice infected with the cercariae exposed to 5 and 10 mg/L of the extract. Conclusions:The aqueous extracts of different parts of B. aegyptiaca exhibited reasonable molluscicidal activity against B. pfeifferi and L. natalensis, as well as cercariacidal activity against S. mansoni cercariae. However, comprehensive laboratory evaluation is recommended prior to field tests of the plant parts since their impact on other

  13. Guest Editorial

    Directory of Open Access Journals (Sweden)

    Mario Döller

    2009-10-01

    minimize the semantic gap in multimedia retrieval.Using the MPEG Query Format for Cross-Modal Identification Matthias Gruhne, Peter Dunker, Ruben Tous This article demonstrates the new multimedia query language (MPEG Query Format in a distributed cross modal retrieval environment.Bridging the Semantic Gap for Texture-based Image Retrieval and Navigation Najlae Idrissi, Jos´e Martinez, Driss Aboutajdine The authors in this paper propose a new approach for interpreting textures in natural terms in order to bridge the semantic gap in image retrieval.Semantic Restructuring of Natural Language Image Captions to Enhance Image Retrieval Kraisak Kesorn, Stefan Poslad Image captions provide useful information and hints for image retrieval. The article introduces a framework that combines Natural Language Processing approaches with Ontologies and LSI in order to extract concepts in image captions.Semantic Concept Mining Based on Hierarchical Event Detection for Soccer Video Indexing Maheshkumar H. Kolekar, Kannappan Palaniappan, Somnath Sengupta, Gunasekaran Seetharaman The detection of semantic concepts in the sports video domain is a challenging task. This article introduces a novel hierarchical framework that supports event sequence detection, semantic concept allocation (e.g., goal scored and summarization.A Multimodal Data Mining Framework for Revealing Common Sources of Spam Images Chengcui Zhang, Wei-Bang Chen, Xin Chen, Richa Tiwari, Lin Yang, Gary Warner Spamming is an overwhelming problem in the today’s communication flow. Related to this, the proposed framework provides means for detecting and clustering spam images in order to track spam gangs.Multimodal Preference Aggregation for Multimedia Information Retrieval Eric Bruno, Stephane Marchand-Maillet The authors present a novel information representation for multimodal data in combination with a machine-learning based retrieval algorithm and highlight their improved efficiency in contrary to the SVM algorithm

  14. Importância epidemiológica de alguns animais silvestres na esquistossomose mansônica Epidemiologic importance of some wild rodents in the schistosomiasis mansoni

    Directory of Open Access Journals (Sweden)

    Urara Kawazoe

    1983-10-01

    Full Text Available Com o intuito de averiguar a importância de alguns roedores como possíveis reservatórios do S. mansoni, na ausência do homem parasitado, foi realizada pesquisa, visando contribuir para o esclarecimento de aspectos ligados à cadeia epidemiológica da esquistossomose, bem como conhecer alguns parâmetros da biologia de certos roedores, em seu habitat semi-natural. O experimento foi realizado num viveiro de 952 m², no município de Taubaté, São Paulo (Brasil, numa área endêmica de esquistossomose mansônica humana, e teve a duração de três anos e seis meses (agosto de 1973 a dezembro de 1976. Foram utilizados como hospedeiros definitivos, Holochilus brasiliensis leucogaster, Zygodontomys lasiurus, Oryzomys nigripes eliurus e Cavia aperea aperea; como hospeideiro intermediário, Biomphalaria tenagophila e posteriormente B. glabrata. Entre agosto de 1973 e janeiro de 1976, não houve encontro de B. tenagophila eliminando cercárias de S. mansoni; não se verificou, também, infecção natural de roedores. Em agosto de 1975, houve introdução acidental de desovas da B. glabrata, cujos adultos, em 1976, apresentaram infecção por S. mansoni em três ocasiões, com índices de 2,0; 1,6 e 0,8%. No mesmo ano de 1976, dois Holochilus, nascidos no Viveiro, eliminaram ovos viáveis de S. mansoni. Foi possível obter dados de 41 H. b. leucogaster, 28 introduzidos e 14 nascidos no local. O exemplar que sobreviveu mais tempo completou 346 dias. Os animais nascidos no Viveiro e capturados pela primeira vez pesavam, em média, 20 a 50 g. Notou-se que o peso corporal aumentou com o tempo e parece não estacionar até a morte do animal. Z. lasiurus e C. a aperea não procriaram e nem adquiriram infecção ao S. mansoni. O. n. eliurus, procriou e permaneceu vivo, em média, menos de 100 dias; não foi observada eliminação de ovos do parasita. É pouco provável que H. b. leucogaster e B. tenagophila mantenham o ciclo da esquistossomose na aus

  15. Ecoepidemiologia da esquistossomose urbana na ilha de Itamaracá, Estado de Pernambuco Ecoepidemiology of urban schistosomiasis in Itamaracá Island, Pernambuco, Brazil

    Directory of Open Access Journals (Sweden)

    Constança Simões Barbosa

    2000-08-01

    Biomphalaria glabrata and 28 capture station were set up. Snails were collected and examined each month throughout a whole year. The results show a seasonal variation in the mollusk population density associated with infection rates and types of breading sites. The importance of this new epidemiological profile of schistosomiasis in the State of Pernambuco relies on the fact that it can be related with the drastic human interference on the environment. Ecological, environmental, and demographic factors as well as the epidemiological characteristics of the disease have social and economic repercussions.

  16. 三角帆蚌热休克蛋白60基因克隆及其表达分析%CLONING AND EXPRESSION ANALYSIS OF HEAT SHOCK PROTEIN 60 GENE FROM HYRIOPSIS CUMINGII

    Institute of Scientific and Technical Information of China (English)

    吴圣楠; 刘大伟; 刘毅; 胡宝庆; 张建强; 王艳; 王婷

    2014-01-01

    利用3′RACE技术,对高通量转录组测序所得三角帆蚌HSP60基因(hcHSP60)长片段(2629 bp)进行了3¢末端克隆,经拼接得到hcHSP60 cDNA全长序列。采用多种分子生物学软件对hcHSP60 cDNA全长序列进行了特征分析,并采用 RT-PCR 技术检测了其组织分布及经冷热应激后的表达变化。结果显示, hcHSP60 cDNA全长为2807 bp,其中开放阅读框为1707 bp,编码568个氨基酸,预测分子量大小为61.04 ku, pH 7.0时的理论等电点为5.63。序列中不存在信号肽与跨膜结构。氨基酸序列保守性分析表明, hcHSP60氨基酸序列与光滑双脐螺HSP60同源性最高(达82%),而与牙鲆、白云金丝鱼HSP60的同源性最低(为75%)。RT-PCR检测结果表明, hcHSP60在肝胰腺中的表达水平最高,而在血液中的表达水平最低。30℃与35℃水温处理三角帆蚌4h后,各组织中hcHSP60表达水平明显上升,表明hcHSP60可能在三角帆蚌耐热应激反应中起着重要作用。%Heat shock protein 60 (HSP60) is an important molecular chaperone protein that mainly exists in the mito-chondria of organism. In the present study, the cDNA sequence of Hyriopsis cumingii HSP60 (hcHSP60) was cloned by 3′rapid amplification of cDNA ends methods (3′-RACE) based on a long chain sequence of hcHSP60 (2629 bp) and was determined by high flux sequencing for transcriptome of H. cumingii blood cells, and its expression in the different tis-sues was detected by using reverse transcription-polymerase chain reaction (RT-PCR). Results showed that the full-length cDNA of hcHSP60 was 2807 bp that contains an open reading frame of 1707 bp, encoding a protein of 568 amino acid residues with 61.04 ku of predicted molecular weight and 5.63 of the theoretical isoelectric point, which was predicted to have no signal peptide and transmembrane helices. The deduced amino acid sequence of hcHSP60 shares the highest identity (82%) with HSP60 of Biomphalaria glabrata, and the phylogenetic

  17. Modul.LES: a multi-compartment, multi-organism aquatic life support system as experimental platform for research in ∆g

    Science.gov (United States)

    Hilbig, Reinhard; Anken, Ralf; Grimm, Dennis

    nitrogene-cycle (concentration of ammonium, nitrite and nitrate) as well as conductivity will be measured. For this long term mission an external food supply as has been used with OmegaHab is not sufficient and, therefore, in OmegaHab-XP a nutrition compartment has been added. OmegaHab-XP is a multi-trophic system, designed as a basic concept and test-bed for future multi-modular platform Modul.LES. OmegaHab-XP comprises four different trophic lev-els. The algae experimental container is used as CO2 / O2 exchanger and serves as oxygen source for all heterotrophic organisms. The fish compartment is divided into two areas -namely a hatchery (larval cichlid fish Oreochromis mossambicus) and a fish tank (subadult cichlids). Once the yolk sack is resorbed (stage 19) the juvenile fish are capable to leave the hatchery via escapements into the fish compartment. In order to enable the development of fish from larval yolk sack stages to subadult fish a nutrition compartment is enclosed: In this nutrition compartment the crustacean Hyalella azteca will reproduce and build up a stable population by feeding on the Rigid Hornwort (Ceratophyllum demersum). Younger crustaceans can cross the barrier to the fish tank and can serve as nutrition for fully developed subadult fish. Waste products of all organisms will be assimilated by the water snail Biomphalaria glabrata. The scientific concept of Modul.LES is to establish a multidisciplinary framework of scientists and areas of scientific research (biophysics, molecular-organismic biology, biochemistry etc.) to analyze impacts of g on plants and animals.

  18. Epidemiological studies of amphistome infections in cattle in the highveld and lowveld communal grazing areas of Zimbabwe

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    D.M. Pfukenyi

    2005-09-01

    Full Text Available During the period between January 1999 and December 2000, the distribution and seasonal patterns of amphistome infections in cattle in the highveld and lowveld communal grazing areas of Zimbabwe were determined through monthly coprological examination. Cattle faecal samples were collected from 12 and nine dipping sites in the highveld and lowveld communal grazing areas, respectively. Patterns of distribution and seasonal fluctuations of intermediate host-snail populations and the climatic factors influencing the distribution were also determined by sampling at monthly intervals for a period of 24 months (November 1998 to October 2000 in six dams and six streams in the highveld and in nine dams in the lowveld communal grazing areas. Each site was sampled for relative snail density and the vegetation cover and type, physical and chemical properties of water, and mean monthly rainfall and temperature were recorded. Aquatic vegetation and grass samples 0-1 m from the edges of the snail habitats were collected monthly to determine the presence or absence of amphistome metacercariae. Snails collected at the same time were individually checked for the emergence of larval stages of amphistomes. A total of 16 264 (calves 5 418, weaners 5 461 and adults 5 385 faecal samples were collected during the entire period of the study and 4 790 (29.5 % of the samples were positive for amphistome eggs. For both regions the number of animals positive for amphistome eggs differed significantly between the 2 years, with the second year having a significantly higher prevalence (P < 0.01 than the first year. Significantly higher prevalences were found in the highveld compared to the lowveld (P < 0.001, for adult cattle than calves (P < 0.01, and in the wet over the dry season (P < 0.01. Faecal egg output peaked from October to March in both years of the study. Bulinus tropicus, Bulinus forskalii and Biomphalaria pfeifferi were recorded from the study sites. The main

  19. 淡水螺类三旋丽卷螺的物种鉴定及其潜在适生区分析%Species identification of freshwater snail Planorbella trivolvis and analysis of its potential distribution

    Institute of Scientific and Technical Information of China (English)

    李晓恒; 高世同; 顾文彪; 张仪; 郭云海

    2015-01-01

    Objective To identify the species classification of an ornamental Planorbidae from a flower market in Shanghai and analyze its potential distribution in China. Methods In August 2013,six freshwater snail specimens were collected from the Wanshang flower market. The species was identified by morphology and molecular biology. An ecological niche model was constructed based on the native geographic presence occurrence data,and projected onto the whole of China to predict the poten⁃tial distribution. Results Their shell external morphology suggested that the specimens belonged to Planorbella trivolvis(Say 1817)of Planorbidae,which is native in North America. The sequence data of a fragment of the mitochondrial cytochrome c oxi⁃dase subunit I(COI)confirmed its identification. A total of 2 294 georeferenced occurrence points in North America were car⁃ried out from the Global Biodiversity Information Facility databases and 614 records with coordinates were used to produce a North American native niche model by a maximum entropy method(Maxent). The projection on China results suggested high probabilities of occurrence mostly in Henan Province and its borderland with nearby provinces. Conclusions P. trivolvis is sim⁃ilarly with Biomphalaria species from shell morphology. It is the first records of the species in China,and the field dispersal is not clear.%目的:对上海市场销售的一种观赏性扁卷螺科淡水螺类进行物种鉴定,同时分析其在中国的潜在适生区。方法于2013年8月在上海市某花鸟市场购买6只淡水螺类标本,通过形态与分子生物学技术进行物种鉴定。运用生态小生境模型建立原产地模型,预测其在中国的潜在适宜生存区域。结果依据贝壳外部形态鉴定为扁卷螺科丽卷螺属三旋丽卷螺,查阅文献表明该物种原产地为北美地区,为广分布物种。通过线粒体细胞色素C氧化酶I(COI)基因片段序列的分子进化距离及系

  20. The C.E.B.A. Mini Module on the STS-107 Mission: Data of Ground Experiments and Preliminary Results of the third Spaceflight of an Artificial Aquatic Ecosystem

    Science.gov (United States)

    Bluem, V.; Paris, F.; Bungart, S.

    The C.E.B.A.S MINI MODULE is the miniaturized version of an artificial aquatic ecosystem consisting of four subcomponents: a ZOOLOGICAL COMPONENT (aquarium for animals), a BOTANICAL COMPONENT (higher water plant bioreactor), a MICROBIAL COMPONENT (bacteria filter) and an ELECTRONICAL COMPONENT (data acquisition, control unit). It has a total volume of 8.6 liters and contains the ovoviviparous teleost Xiphophorus helleri (swordtail), larvae of the ovuliparous cichlid fish Oreochromis mossambicus, the pulmonate water snail Biomphalaria glabrata, the rootless (non-graivitropic) higher water plant Ceratophyllum demersum (hornweed) and special strains of ammonia oxidizing bacteria. This device was already flown twice successfully in space with the space shuttle missions STS- 89 and STS-90 (NEUROLAB) in 1998. It will fly a third time with the STS-107-mission the launch of which has been repeatedly shifted December 222, April 2001, October 2001) and is now finally scheduled for June 2002. The main focus of scientific interest in the past missions were system performance, reproductive biology (reproductive function of adult females including endocrine system, fertilization, gonadal development in juveniles), vestibular and immunological research in X. helleri, embryology and shell formation in B. glabrata, general morphology and physiology of C. demersum and groth rates of the bacteria. The standard load of the system were 4 adult and 200 neonate X. helleri, 30 adult B. glabrata and 30 g of C. demersum. The evaluation of these experiments showed that all reproductive functions and the immune system of the fishes snails remained undisturbed in space, that the snails developed normally and exhibited no disturbance of shell formation and that the plants showed growth and photosynthesis rates comparable to those on Earth. So, as a logical continuation, the main topics for the STS-107 mission are the remaining important questions in X. helleri biology: puberty, male sexual

  1. Estudo seccional sobre esquistossomose mansônica no Município de Riachuelo, Estado de Sergipe

    Directory of Open Access Journals (Sweden)

    Antonio Paulo de Menezes

    1980-12-01

    da esquistossomose mansônica, estando 12 naturalmente infectados. A única espécie encontrada foi a B. glabrata.A sectional dinic and epidemiological study was performed aiming to define the morbidity of the S. mansoni infection in the human population of Riachuelo, Sergipe, in Northeastern of Brazil. Eight hundred and fifty persons from the above community (25% were random-selected and studied: 835 of them had a stool examination done by Lutz sedimentation (Hoffman, Pons and Janer technique and S. mansoni egg counting by Katos' method. A skin test with antigen from adult worm was performed in 393 persons from the sample. The average prevalence of the S. mansoni infections in the population (viable eggs in the stool was 50.54%. The prevalence of the infection by S. mansoni in children under 5 years was considerable lower (6.15% than in the groups from 6-10 (41.5% and in those from 11 to 50 years (average of 75% of infection. The skin test positivity was marked higher than the stool examination in ali ihese groups, but there was a good correaltion between these two methods in ali groups. However in the groups over 50 years there was a drop to 48.3% in the stool positivity for S. mansoni eggs but the skin test remained with a very high positivity (94.11%. There was no difference of positivity either in the stools or in the skin test in relation to the sex but regarding to the race there was a higher prevalence of the infection in blacks and ",mestiços" than in whites. Clinically 73.17% of the infected people were classified in group I (intestinal infection, 24.39% in group II (hepato-intestinal and only 2.43% in the group III (hepatosplenic form. Biomphalaria glabrata was the single vector found in five focci surrounding the community. The infection rate by cercarias of S. mansoni in 1.208 snails colected was ofabout 1% (12 snails positives.