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Sample records for biomphalaria straminea dunker

  1. 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,

  2. 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

  3. Modification of Biomphalaria straminea eggs enclose induced by gamma radiation

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    A vector of Schistosomiasis, the mollusk Biomphalaria straminea, can procreate by means of sexual - when in colonies - or by hermaphrodite fecundation, if isolated. In order to study its reproductive behavior under gamma radiation, 540 snails kept in colony and 540 maintained isolated in individual aquariums, were irradiated with doses, 0, 2,5, 5,0, 7,5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 80, 160, 320 and 640 Gy of gamma-rays from a 60 Co. source, and were observed during 30 days. Daily, the off spring were collected from the aquariums, its eggs counted and maintained in Petri's plate, in water. After eight days, the eggs were counted again and the difference with the first count representing the hatched eggs. As a result, the eggs from the snails kept in colony showed a greater number of encloses than those from the isolated snails, ranging from 2,5 to 40 Gy. Beyond this dose the difference between the two observed groups were statistically non significant, leading to suppose a greater resistance of the sexually fecundation to the influence of gamma-rays. (author). 16 refs, 1 fig, 1 tab

  4. 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

  5. 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.

  6. 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.

  7. Esquistossomose: nova ocorrência de Biomphalaria straminea em Belo Horizonte, Minas Gerais Schistosomiasis: new occurrence of Biomphalaria straminea in Belo Horizonte, Minas Gerais

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    Cecília Pereira de Souza

    1996-12-01

    Full Text Available Em Belo Horizonte, Minas Gerais, Brasil, a Biomphalaria straminea é encontrada na região da Pampulha. Recentemente, o molusco foi encontrado em valas da antiga Barragem de Santa Lúcia, foco extinto de esquistossomose transmitida por B. glabrata. Os moluscos foram coletados e examinados para verificar se estavam naturalmente infectados com Schistosoma mansoni. Os exemplares negativos foram usados para criação ou infecção com a cepa LE de S. mansoni, mantida no laboratório, e outra cepa VGS, obtida de ovos de fezes de escolar de Belo Horizonte. Dentre 1.890 moluscos capturados em 1994 e 1995, nenhum estava infectado com S. mansoni. Dentre 87 exemplares coletados no criadouro e expostos à cepa LE, nove (10,3% eliminaram cercárias; dentre 83 moluscos da F1, dez (12,0% eliminaram cercárias e dentre 88 exemplares coletados e expostos à cepa VGS, dez (11,3% eliminaram cercárias. Em Belo Horizonte, a esquistossomose é transmitida por B. glabrata e B. tenagophila. Entretanto, atualmente existe o risco de aparecimento de novo foco, no qual a B. straminea poderá vir a ser a transmissora, se medidas profiláticas adequadas não forem tomadas pelas autoridades responsáveis pela construção de um parque e lago no local.In Belo Horizonte, Minas Gerais, Brazil, the snail Biomphalaria straminea was found in the Pampulha region. Recently the snail was found in ditches in the old Santa Lúcia Reservoir, a now-extinct focus of schistosomiasis transmission by B. glabrata. The snails were collected and examined to verify whether they were naturally infected with Schistosoma mansoni. Negative specimens were used for breeding or infection with the LE strain of S. mansoni from the laboratory and another strain obtained from eggs found in the feces of a schoolchild (VGS from Belo Horizonte. Among the 1890 snails collected from 1994 to 1995, none were infected with S. mansoni. Among 87 snails collected and exposed to the LE strain, 9 (10.3% shed cercariae

  8. 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.

  9. Modification of Biomphalaria straminea eggs enclose induced by gamma radiation; Modificacoes da eclosao de ovos de Biomphalaria straminea induzidas pela radiacao gama

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    Melo, A.M.M.A.; Leal, M.A.M.; Motta, M.A. da [Pernambuco Univ., Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia

    1994-12-31

    A vector of Schistosomiasis, the mollusk Biomphalaria straminea, can procreate by means of sexual - when in colonies - or by hermaphrodite fecundation, if isolated. In order to study its reproductive behavior under gamma radiation, 540 snails kept in colony and 540 maintained isolated in individual aquariums, were irradiated with doses, 0, 2,5, 5,0, 7,5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 80, 160, 320 and 640 Gy of gamma-rays from a {sup 60} Co. source, and were observed during 30 days. Daily, the off spring were collected from the aquariums, its eggs counted and maintained in Petri`s plate, in water. After eight days, the eggs were counted again and the difference with the first count representing the hatched eggs. As a result, the eggs from the snails kept in colony showed a greater number of encloses than those from the isolated snails, ranging from 2,5 to 40 Gy. Beyond this dose the difference between the two observed groups were statistically non significant, leading to suppose a greater resistance of the sexually fecundation to the influence of gamma-rays. (author). 16 refs, 1 fig, 1 tab.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. Effects of Bayluscide WP 70® on the Survival and Water-leaving Behaviour of Biomphalaria straminea, Snail Host of Schistosomiasis in Northeast Brazil

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    Sarquis Otília

    1997-01-01

    Full Text Available The toxic and behavioural effects of niclosamide (Bayluscide WP 70® on Biomphalaria straminea from a highly endemic area of schistosomiasis in northeastern Brazil were investigated through laboratory bioassays. The LD50 and LD90 were 0.114 mg/l and 0.212 mg/l, respectively. Water-leaving behaviour occurred among 14% to 30% of the snails in the presence of sublethal doses of niclosamide and among 16% of the controls. It was concluded that both the relatively low susceptibility to niclosamide and water-leaving behaviour of local B. straminea may be responsible for the recolonization of transmission foci after mollusciciding. It was suggested that recently improved measures of snail control, such as controlled-release formulations of niclosamide and plant molluscicides should be considered in areas where snail control is recommended

  16. [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].

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    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.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. Molecular identification of similar species of the genus Biomphalaria (Mollusca: Planorbidae determined by a polymerase chain reaction-restriction fragment length polymorphism

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    Caldeira Roberta Lima

    1998-01-01

    Full Text Available The freshwater snails Biomphalaria straminea, B. intermedia, B. kuhniana and B. peregrina, are morphologically similar; based on this similarity the first three species were therefore grouped in the complex B. straminea. The morphological identification of these species is based on characters such as vaginal wrinkling, relation between prepuce: penial sheath:deferens vas and number of muscle layers in the penis wall. In this study the polymerase chain reaction restriction fragment length polymorphism technique was used for molecular identification of these molluscs. This technique is based on the amplification of the internal transcribed spacer regions ITS1 e ITS2 of the ribosomal RNA gene and subsequent digestion of these fragments by restriction enzymes. Six enzymes were tested: Dde I, Mnl I, Hae III, Rsa I, Hpa II e Alu I. The restriction patterns obtained with DdeI presented the best profile for separation of the four species of Biomphalaria. The profiles obtained with all the enzymes were used to estimate the genetic distances among the species through analysis of common banding patterns.

  4. Plant regeneration from protoplasts of Gentiana straminea Maxim

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    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%.

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

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    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.

  6. Toxicity of neem's oil, a potential biocide against the invasive mussel Limnoperna fortunei (Dunker 1857)

    OpenAIRE

    Pereyra, Patricio J.; Rossini, Gustavo B.; Gustavo Darrigran

    2012-01-01

    The golden mussel Limnoperna fortunei (Dunker 1857) is one of the most distributed Nuisance Invasive Species (NIS) in South America, and a threat of great concern for the industry of the area. In this study, we carried out toxicity tests made with a Neem's oil solution with L. fortunei larvae and benthonic adults (7, 13 and 19 ± 1 mm). Tests with non-target species (Daphnia magna, Lactuca sativa and Cnesterodon decemmculatus) were also made with the aim to evaluate the potential toxicity of t...

  7. 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.

  8. Levantamento planorbídico do Estado de São Paulo (Brasil: 4ª Região Administrativa Planorbidic survey of the 4th Administrative Region of the State of S. Paulo, Brazil

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    Jorge Faria Vaz

    1987-10-01

    Full Text Available A fim de conhecer a distribuição dos hospedeiros intermediários de S. mansoni no Estado de São Paulo (Brasil, a Superintendência de Controle de Endemias (SUCEN procedeu a amplo inquérito malacológico em todos os municípios paulistas que teve a duração de 4 anos. As pesquisas realizadas na 4ª Região Administrativa que tem sede em Sorocaba e que constituem o objeto do presente relato, mostraram que Biomphalaria tenagophila (d'Orbigny, 1835 ocorre em 26 dos 59 municípios nela compreendidos. Biomphalaria glabrata (Say, 1818 é encontrada em 9 municípios e Biomphalaria straminea (Dunker, 1848, em 2. Vários casos de esquistossomose em migrantes já foram observados na área estudada. B. tenagophila parece estar implicada na cadeia natural de transmissão de S. mansoni em Itu e em São Roque, municípios em que foram descobertos os dois únicos casos da doença, até agora considerados como autóctones em toda a região.In order to discover the actual distribution of the intermediate hosts of Schistosoma mansoni in the State of São Paulo, Brazil, a planorbidic survey was made in the 572 counties of the State. Investigation carried out in the State's 4th Administrative Region, which comprises 59 counties, has shown that Biomphalaria tenagophila (d'Orbigny, 1835, Biomphalaria glabrata (Say, 1818 and Biomphalaria straminea (Dunker, 1848 are found, respectively, in twenty nine, nine and two of the counties. Many cases of schistosomiasis were detected among migrants to the Region but, up to the present, only two patients - at Itu and São Roque - could have contracted, the disease in the studied area. It seems that the fluke was intermediated by B. tenagophila.

  9. Toxicity of Neem's oil, a potential biocide against the invasive mussel Limnoperna fortunei (Dunker 1857).

    Science.gov (United States)

    Pereyra, Patricio J; Rossini, Gustavo B; Darrigran, Gustavo

    2012-12-01

    The golden mussel Limnoperna fortunei (Dunker 1857) is one of the most distributed Nuisance Invasive Species (NIS) in South America, and a threat of great concern for the industry of the area. In this study, we carried out toxicity tests made with a Neem's oil solution with L. fortunei larvae and benthonic adults (7, 13 and 19 ± 1 mm). Tests with non-target species (Daphnia magna, Lactuca sativa and Cnesterodon decemmculatus) were also made with the aim to evaluate the potential toxicity of the Neem's solution in the environment. The LC(100) of Neem's solution obtained for larvae was 500 µl/L, a value much higher than the one obtained for D. magna and C. decemmaculatus. Thus, we recommend that it should not be used in open waters. However, since the adults were killed in 72 h and the larvae in 24 h, this product can be used in closed systems, in man-made facilities. PMID:22990602

  10. Toxicity of neem's oil, a potential biocide against the invasive mussel Limnoperna fortunei (Dunker 1857

    Directory of Open Access Journals (Sweden)

    Patricio J. Pereyra

    2012-12-01

    Full Text Available The golden mussel Limnoperna fortunei (Dunker 1857 is one of the most distributed Nuisance Invasive Species (NIS in South America, and a threat of great concern for the industry of the area. In this study, we carried out toxicity tests made with a Neem's oil solution with L. fortunei larvae and benthonic adults (7, 13 and 19 ± 1 mm. Tests with non-target species (Daphnia magna, Lactuca sativa and Cnesterodon decemmculatus were also made with the aim to evaluate the potential toxicity of the Neem's solution in the environment. The LC100 of Neem's solution obtained for larvae was 500 µl/L, a value much higher than the one obtained for D. magna and C. decemmaculatus. Thus, we recommend that it should not be used in open waters. However, since the adults were killed in 72 h and the larvae in 24 h, this product can be used in closed systems, in man-made facilities.O Mexilhão dourado Limnoperna fortunei (Dunker 1857 é uma das espécies invasoras melhor distribuídas na América do Sul, sendo motivo de grande preocupação para a indústria local. Neste estudo, nós realizamos ensaios de toxicidade de soluções de Óleo de Neem em larvas e adultos bentônicos de L. fortune (7, 13 e 19 ± 1 mm. Com o objetivo de avaliar o potencial tóxico do Óleo de Neem no ambiente também foram realizados testes com organismos não alvo (Daphnia magna, Lactuca sativa e Cnesterodon decemmculatus. A LC100 da solução de Neem para larvas foi 500 µl/L, um valor muito superior ao obtido para D. magna e C. decemmaculatus. Desta forma, nossa recomendação é que este óleo não deve ser utilizado em ambientes naturais abertos. No entanto, uma vez que os adultos morreram em 72h e as larvas em 24h, este produto pode ser utilizado em sistemas fechados construídos pelo homem.

  11. Breeding of Biomphalaria tenagophila in mass scale

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    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.

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

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    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.

  13. 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

  14. 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

  15. Reproductive ecology of the Qinghai-Tibet Plateau endemic Gentiana straminea (Gentianaceae), a hermaphrodite perennial characterized by herkogamy and dichogamy

    Science.gov (United States)

    Duan, Yuan-wen; He, Ya-ping; Liu, Jian-quan

    2005-05-01

    The combined occurrence of both herkogamy and dichogamy in a hermaphrodite species has been considered to strongly favour outcrossing. In this study, we investigated in detail the reproductive ecology of Gentiana straminea Maxim. (Gentianaceae), a hermaphrodite perennial endemic to the Qinghai-Tibet Plateau. In a series of observations and experiments over four consecutive years, we examined whether the combination of dichogamy and herkogamy in individual flowers completely prevents geitonogamous pollen transfer in this species. The mode of floral development clearly indicates that autonomous self-pollination is completely avoided through herkogamy and dichogamy in individual flowers. This implication was confirmed by the breeding experiments, since no seed was produced when flowers were isolated. However, this gentian proved to be highly self-compatible when geitonogamous selfing was artificially induced. Many flowers opened simultaneously on individual plants, the ratio of male to female phase flowers was close to 2:1 in each inflorescence at the full anthesis phase, and they were randomly distributed amongst the upper, middle and lower parts of each stem's inflorescence. On average, Bombus sushikini Skorikov, the most frequent visitor and only legitimate pollinator of G. straminea, visited nearly two flowers per inflorescence, and four flowers per plant. Among the pollinators' foraging bouts, the proportions of geitonogamous visits to inflorescences or flowers within an individual plant were 29% and 37%, respectively. Therefore, despite the strict dichogamous and herkogamous characteristics of the individual flowers, geitonogamous selfing might still prevail in G. straminea because of the size of its floral displays and the continuous visiting behavior of B. sushkini.

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

    OpenAIRE

    Queli Teixeira Lemos

    1999-01-01

    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 deposi...

  17. 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.

  18. 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.

  19. Characterization of Biomphalaria orbignyi, Biomphalaria peregrina and Biomphalaria oligoza by polymerase chain reaction and restriction enzyme digestion of the internal transcribed spacer region of the RNA ribosomal gene

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    Spatz Linus

    2000-01-01

    Full Text Available The correct identification of Biomphalaria oligoza, B. orbignyi and B. peregrina species is difficult due to the morphological similarities among them. B. peregrina is widely distributed in South America and is considered a potential intermediate host of Schistosoma mansoni. We have reported the use of the polymerase chain reaction and restriction fragment length polymorphism analysis of the internal transcribed spacer region of the ribosomal DNA for the molecular identification of these snails. The snails were obtained from different localities of Argentina, Brazil and Uruguay. The restriction patterns obtained with MvaI enzyme presented the best profile to identify the three species. The profiles obtained with all enzymes were used to estimate genetic similarities among B. oligoza, B. peregrina and B. orbignyi. This is also the first report of B. orbignyi in Uruguay.

  20. Atividade moluscicida de alguns produtos naturais sobre Biomphalaria glabrata Molluscicide activity of some natural products on Biomphalaria glabrata

    OpenAIRE

    Nelymar Martineli Mendes; Cecília Pereira de Souza; Neusa Araújo; José Pedro Pereira; Naftale Katz

    1986-01-01

    Foi avaliada, em laboratório, a ação moluscicida de extratos aquosos (macerado e fervido), hexânico e etanólico de Aristolochia brasiliensis, Caesalpinia peltophoroides, Caesalpinia pulcherrima, Delonix regia, Spathodea campanulata e Tibouchina scrobiculata. As soluções dos extratos obtidos foram testadas sobre caramujos adultos e desovas de Biomphalaria glabrata, criados em laboratório, nas concentrações de 1, 10, 20, 200 e 1000ppm. Dos extratos testado o mais ativo foi o etanólico das flore...

  1. 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.

  2. Atividade moluscicida de alguns produtos naturais sobre Biomphalaria glabrata Molluscicide activity of some natural products on Biomphalaria glabrata

    Directory of Open Access Journals (Sweden)

    Nelymar Martineli Mendes

    1986-03-01

    Full Text Available Foi avaliada, em laboratório, a ação moluscicida de extratos aquosos (macerado e fervido, hexânico e etanólico de Aristolochia brasiliensis, Caesalpinia peltophoroides, Caesalpinia pulcherrima, Delonix regia, Spathodea campanulata e Tibouchina scrobiculata. As soluções dos extratos obtidos foram testadas sobre caramujos adultos e desovas de Biomphalaria glabrata, criados em laboratório, nas concentrações de 1, 10, 20, 200 e 1000ppm. Dos extratos testado o mais ativo foi o etanólico das flores da D. regia (flamboyant que apresentou atividade moluscicida sobre caramujos adultos na concentração de 20ppm.The molluscicide activity of aqueous (macerated and boiled, hexamic and ethylic extracts of Aristolochia brasiliensis, Caesalpinia peltophoroides, Caesalpinia pulcherrima, Delonix regia, Spathodea campanulata and Tibouchina scrobiculata was evaluated in the laboratory. The solutions obtained from those extracts were tested on adults and egg masses of Biomphalaria glabrata reared in the laboratory at 1, 10, 20, 100 and 1000ppm concentrations. The most active of the extracts studied was D. regia flowers' (flamboyant ethylic extracts which presented molluscicidal activity on adult snails at 20ppm.

  3. 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

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    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.

  4. 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.

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    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

  5. 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.

  6. 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...

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

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    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.

  8. 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.

  9. 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.

  10. 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

    Directory of Open Access Journals (Sweden)

    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.

  11. Biomphalaria alexandrina as a bioindicator of metal toxicity.

    Science.gov (United States)

    Habib, Mohamed R; Mohamed, Azza H; Osman, Gamalat Y; Mossalem, Hanan S; Sharaf El-Din, Ahmed T; Croll, Roger P

    2016-08-01

    Heavy metals are common environmental pollutants to the aquatic ecosystems. Several aquatic species have been used as bioindicators and biomonitoring subjects for heavy metals pollution. In the present study, the effects of cadmium (Cd) and manganese (Mn) on the survival, attachment, locomotion, and feeding behaviours of the gastropod snail Biomphalaria alexandrina were determined. The short-term (96 h) LC50 for Cd and Mn were found to be 0.219 and 154.2 mg/l, respectively. Long-term exposures (16-20 days) to ascending concentrations of Cd (0.01-1 mg/l) and Mn (50-500 mg/l) also caused gradual decreases in the survival rate of B. alexandrina in a dose-dependent manner. Attachment, locomotion and feeding behaviours of snails exposed to lethal and sublethal concentrations of Cd and Mn at acute (96 h) and chronic exposure (24 days) intervals, respectively, were also recorded. Compared to controls, a significant decrease (p ≤ 0.05) was recorded in the different behaviours of exposed snails. These changes in behaviour would potentially impact the snail's ability to survive in the wild. Although Cd caused a more severe decline in snail survivorship than Mn, the behavioural effects of Mn were much more severe than Cd when the metals were roughly matched for lethality. In sum, the present study demonstrates B. alexandrina to be a sensitive bioindicator and model organism to assess heavy metals risk factors for severe toxicity in freshwater ecosystems. PMID:27209558

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. 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

  17. Atividade moluscicida do extrato butílico de Phytolaca dodecandra (Endod) sobre Biomphalaria glabrata Molluscicide activity of a buthanol extract of Phytolacca dodecandra (Endod) on Biomphalaria glabrata

    OpenAIRE

    Cecília Pereira de Souza; Nelimar Martinelli Mendes; Neusa Araújo; Naftale Katz

    1987-01-01

    O extrato butílico da Phytolacca dodecandra (tipo 44) obtido de frutos procedentes da Etiópia, foi testado como moluscicida em nosso laboratório e no campo. As concentrações letais, CL90, com 24 horas de exposição, para Biomphalaria glabrata adulta, recém-eclodidas e desovadas foram de 4,5, 23,0 e 102,0 ppm, respectivamente. Para peixes, Lebistes reticulatus, a CL90 foi de 2,0 ppm. Esses resultados foram semelhantes aos obtidos por Lemma em 1984, na Etiópia. Em dois criadouros com água parada...

  18. Repovoamento de criadouros de Biomphalaria glabrata após tratamento com niclosamida Repopulation of breeding habitats of Biomphalaria glabrata after treatment with niclosamide

    OpenAIRE

    Cecília Pereira de Souza; Nelymar Martineli Mendes

    1991-01-01

    Experimentos foram feitos no laboratório e no campo nos anos de 1980 a 1984, objetivando detectar as causas do repovoamento de criadouros de Biomphalaria glabrata após tratamento com niclosamida. Os bioensaios no laboratório mostraram que a suscetibilidade à niclosamida emulsionável de B. glabrata coletada mensalmente em um sistema de valas de irrigação, variou durante o ano. As concentrações letais CL90 foram 0,15 mgl-1 a 0,60 mgl-1, apresentando diferenças significantes estatisticamente (p ...

  19. Gamma 60Co DL50/30 of Biomphalaria glabrata (Say, 1818) DL50/30 raios gama de 60Co em Biomphalaria glabrata (Say, 1818)

    OpenAIRE

    Elaine Barros da Costa CARVALHO; Melo, Ana Maria Mendonça de Albuquerque; Mauricy Alves da MOTTA

    1999-01-01

    The variation of resistance to 60Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose) to increasing doses of gamma radiation. Doses of 10, 20, 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell 60Co irradiator, were applied to the test groups and two groups control (non-irradiated) of snails - isolated and colony...

  20. Schistosomiasis Control Using Piplartine against Biomphalaria glabrata at Different Developmental Stages

    OpenAIRE

    Rapado, Ludmila Nakamura; Pinheiro, Alessandro de Sá; Lopes, Priscila Orechio de Moraes Victor; Fokoue, Harold Hilarion; Scotti, Marcus Tullius; Marques, Joaquim Vogt; Ohlweiler, Fernanda Pires; Borrely, Sueli Ivone; Pereira, Carlos Alberto de Bragança; Kato, Massuo Jorge; Nakano, Eliana; Yamaguchi, Lydia Fumiko

    2013-01-01

    Background Schistosomiasis is one of the most significant diseases in tropical countries and affects almost 200 million people worldwide. The application of molluscicides to eliminate the parasite's intermediate host, Biomphalaria glabrata, from infected water supplies is one strategy currently being used to control the disease. Previous studies have shown a potent molluscicidal activity of crude extracts from Piper species, with extracts from Piper tuberculatum being among the most active. M...

  1. Neotropical planorbid snails with apertural lamellae: I. Biomphalaria helophila (Orbigny, 1835)

    OpenAIRE

    W. Lobato Paraense

    1996-01-01

    A definition of Biomphalaria helophila (Orbigny, 1835) is presented, based on examination of the shell and reproductive system of topotypic specimens and extended to a number of samples from other localities. The following nominal species and subspecies, collected from type localities, proved junior synonyms of B. helophila: Planorbis albicans Pfeiffer, 1839; Planorbis dentatus Gould, 1844; Planorbis dentiferus CB Adams, 1845; Planorbis dentiferus edentatus CB Adams, 1851; Planorbis dentiens ...

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

    OpenAIRE

    F. Pimentel-Souza; V. T. Schall; N. D. C. Barbosa; Schettino, M.; R. Lautner Júnior.

    1988-01-01

    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 measur...

  3. Circulating Biomphalaria glabrata hemocyte subpopulations possess shared schistosome glycans and receptors capable of binding larval glycoconjugates

    OpenAIRE

    YOSHINO, TIMOTHY P.; Wu, Xiao-Jun; Gonzalez, Laura A.; Cornelis H Hokke

    2012-01-01

    Host lectin-like recognition molecules may play an important role in innate resistance in Biomphalaria glabrata snails to larval schistosome infection, thus implicating parasite-expressed glycans as putative ligands for these lectin receptors. While host lectins may utilize specific glycan structures for parasite recognition, it also has been hypothesized that the parasite may use this system to evade immune detection by mimicking naturally-expressed host glycans, resulting in reduced immunor...

  4. 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.

  5. 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)

  6. 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

  7. Study on Bionic Wild Cultivation Technique of Gentiana Straminea in the Qinghai-Tibet Plateau%青藏高原麻花艽仿生栽培技术研究

    Institute of Scientific and Technical Information of China (English)

    田丰; 李永平; 俞科贤; 李福安; 魏全嘉; 王有庆; 王祖训

    2012-01-01

    采用对比设计对麻花艽仿生栽培方式和常规栽培进行试验.结果表明:在青海麻花艽适生地区采用仿生栽培方式种植麻花艽更接近麻花艽的野生环境.麻花艽的出苗期、第二年返青期均早于常规栽培方式;出苗密度、返青率、单株叶片数、叶长、单株鲜重、根鲜重等均显著高于常规栽培方式;龙胆苦苷含量与常规栽培没有显著差异.仿生栽培方式的人力、物力的投入量少于常规栽培.%Comparative experiment was carried out between bionic wild and conventional cultivation of Gentiana straminea in Qinghai-Tibet plateau. The results indicated that the growth situation of Gentiana straminea planted with bionic wild cultivation was almost same with plant grown in wild environment condition in Qinghai potential growth area. Emergence period and recovering date of Gentiana straminea in following year were earlier than plants planted with conventional cultivation;seedling density, recovering rate,the number of leaves, length of leaf,fresh weight per plant and fresh weight per plant root were obviously higher than plants planted with conventional cultivation; There was no significant difference on gentiopicroside content between bionic wild and conventional cultivation. The cost of manpower and materials on bionic cultivation were less than conventional cultivation.

  8. 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.

  9. Repovoamento de criadouros de Biomphalaria glabrata após tratamento com niclosamida Repopulation of breeding habitats of Biomphalaria glabrata after treatment with niclosamide

    Directory of Open Access Journals (Sweden)

    Cecília Pereira de Souza

    1991-08-01

    Full Text Available Experimentos foram feitos no laboratório e no campo nos anos de 1980 a 1984, objetivando detectar as causas do repovoamento de criadouros de Biomphalaria glabrata após tratamento com niclosamida. Os bioensaios no laboratório mostraram que a suscetibilidade à niclosamida emulsionável de B. glabrata coletada mensalmente em um sistema de valas de irrigação, variou durante o ano. As concentrações letais CL90 foram 0,15 mgl-1 a 0,60 mgl-1, apresentando diferenças significantes estatisticamente (p Experiments were undertaken both in the laboratory and in the field between 1980-1984 to evaluate the causes of repopulation of breeding places of Biomphalaria glabrata following treatment with Niclosamide. Laboratory bioassays showed that the susceptibility to emulsifiable Niclosamide of B. glabrata collected monthly from an irrigation ditch system varied during the year. Lethal concentrations (LC90 ranged between 0.15 mg/l-1 and 0.60 mg/l-1. Statistically significant differences (alpha=0.01 were evident between the months of May/82 and January/83 and December/82 and January/83, and were related to snail nutrition. In the field two types of foci of B. glabrata were treated with 10 ppm of Niclosamide. The first one consisted of a reservoir of 12000 1 of water in which 14.5% of snails were infected with Schistosoma mansoni. One application of molluscicide followed by cleaning of the reservoir eliminated all the snails. The second one consisted of an irrigation system in which 5.6% of the snails were infected with S. mansoni. One application of molluscicide without cleaning the ditches reduced the density of snails by 98%. The causes of the survival of 2.0% of the snails in the ditches are discussed in relation to the substratum of the breeding places and the treatment technique.

  10. Atividade moluscicida do extrato butílico de Phytolaca dodecandra (Endod sobre Biomphalaria glabrata Molluscicide activity of a buthanol extract of Phytolacca dodecandra (Endod on Biomphalaria glabrata

    Directory of Open Access Journals (Sweden)

    Cecília Pereira de Souza

    1987-09-01

    Full Text Available O extrato butílico da Phytolacca dodecandra (tipo 44 obtido de frutos procedentes da Etiópia, foi testado como moluscicida em nosso laboratório e no campo. As concentrações letais, CL90, com 24 horas de exposição, para Biomphalaria glabrata adulta, recém-eclodidas e desovadas foram de 4,5, 23,0 e 102,0 ppm, respectivamente. Para peixes, Lebistes reticulatus, a CL90 foi de 2,0 ppm. Esses resultados foram semelhantes aos obtidos por Lemma em 1984, na Etiópia. Em dois criadouros com água parada, tratados com 10ppm de estrato butílico e 3ppm de niclosamida, ocorreu 84,0 e 100,0% de mortalidade B. glabrata, respectivamente. Os dois produtos foram tóxicos para peixes (L. reticulatus no campo. É discutida a possibilidade do uso de moluscidas de origem vegetal, como alternativa para o combate a focos de esquistossomose no Brasil.A buthanol extract of Phytolacca dodecandra (type 44 obtained from Ethiopia berries, was tested as molluscicide in our laboratory and in the field. The lethal dose (LD90 for adult snails, newly hatched and egg-masses of Biomphalaria glabrata, in 24 hours exposure, were of 4.5, 23.0 and 102.0 ppm respectively. The LD90 for the fish Lebistes reticulatus was of 2.0 ppm. These results are similar to those of Lemma (1984 in Ethiopia. In two water ponds treated with 10 ppm of the buthanol extract or 3 ppm of niclosamide the mortality rates of B. glabrata were of 84.6 and 100.0%, respectively. Both treatments were toxic for L. reticulatus in the field trials. The possibility of using molluscicides derived from plants is discussed as an alternative for treatment of schistosomiasis foci in Brazil.

  11. 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.

  12. 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

    Directory of Open Access Journals (Sweden)

    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

  13. OVICIDAL EFFECT OF PIPERACEAE SPECIES ON Biomphalaria glabrata, Schistosoma mansoni HOST

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    Ludmila Nakamura Rapado

    2013-12-01

    Full Text Available SUMMARY Schistosomiasis is a neglected disease with public health importance in tropical and subtropical regions. An alternative to the disease control is the use of molluscicides to eliminate or reduce the intermediate host snail population causing a reduction of transmission in endemic regions. In this study nine extracts from eight Piperaceae species were evaluated against Biomphalaria glabrata embryos at blastula stage. The extracts were evaluated in concentrations ranging from 100 to 10 mg/L. Piper crassinervium and Piper tuberculatum extracts were the most active (100% of mortality at 20 mg/L and 30 mg/L respectively.

  14. OVICIDAL EFFECT OF PIPERACEAE SPECIES ON Biomphalaria glabrata, Schistosoma mansoni HOST

    Science.gov (United States)

    Rapado, Ludmila Nakamura; Lopes, Priscila Orechio de Moraes; Yamaguchi, Lydia Fumiko; Nakano, Eliana

    2013-01-01

    SUMMARY Schistosomiasis is a neglected disease with public health importance in tropical and subtropical regions. An alternative to the disease control is the use of molluscicides to eliminate or reduce the intermediate host snail population causing a reduction of transmission in endemic regions. In this study nine extracts from eight Piperaceae species were evaluated against Biomphalaria glabrata embryos at blastula stage. The extracts were evaluated in concentrations ranging from 100 to 10 mg/L. Piper crassinervium and Piper tuberculatum extracts were the most active (100% of mortality at 20 mg/L and 30 mg/L respectively). PMID:24213196

  15. Neotropical planorbid snails with apertural lamellae: I. Biomphalaria helophila (Orbigny, 1835

    Directory of Open Access Journals (Sweden)

    W Lobato Paraense

    1996-04-01

    Full Text Available A definition of Biomphalaria helophila (Orbigny, 1835 is presented, based on examination of the shell and reproductive system of topotypic specimens and extended to a number of samples from other localities. The following nominal species and subspecies, collected from type localities, proved junior synonyms of B. helophila: Planorbis albicans Pfeiffer, 1839; Planorbis dentatus Gould, 1844; Planorbis dentiferus CB Adams, 1845; Planorbis dentiferus edentatus CB Adams, 1851; Planorbis dentiens Morelet, 1849; Planorbula dentiens edentula Fischer & Crosse, 1880; Planorbis stagnicola Morelet, 1851; and Tropicorbis shimeki FC Baker, 1945. B. helophila was also identified in samples from Costa Rica, Guatemala, Haiti, Dominican Republic, Puerto Rico and Barbados.

  16. Effects of Plagiorchis elegans (Digenea: Plagiorchiidae) infection on the reproduction of Biomphalaria glabrata (Pulmonata: Planorbidae).

    Science.gov (United States)

    Zakikhani, M; Rau, M E

    1998-10-01

    Infection with the digenean parasite Plagiorchis elegans dramatically reduced the reproductive output of Biomphalaria glabrata exposed to the parasite as juveniles or adults. The total number of eggs produced by infected snails was reduced to approximately 7 and 13% of control values, respectively. Parasitic castration was attributed to the presence of mother sporocysts that readily established in the tissues of this incompatible host. Infection did not result in the production of cercariae but significantly shortened the life span of juvenile and adult B. glabrata by approximately 23 and 10%, respectively. Plagiorchis elegans also castrated its compatible host, Stagnicola elodes. PMID:9794632

  17. New insights into the amphibious life of Biomphalaria glabrata and susceptibility of its egg masses to fungal infection

    Science.gov (United States)

    Egg masses of an aquatic snail, Biomphalaria glabrata, matured, and juveniles subsequently eclosed and were mobile in a stable water film of transitory habitats simulated by two different simple test devices described here. The viability of eggs maintained in an unstable film due to low ambient mois...

  18. Morphological characterization of the hemocytes of the pulmonate snail Biomphalaria tenagophila

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    Margherita Anna Barracco

    1993-03-01

    Full Text Available The blood cells of the pulmonate snail Biomphalaria tenagophila, an important transmiter of the trematode Schistosoma mansoni in Brazil, were examined by ligth and transmission electron microscopy (TEM. Two hemocyte types were identified: hyalinocytes and granulocytes. Hyalinocytes are small young (immature, poorly spreading cells, which have a high nucleocytoplasmic ratio and are especially rich in free ribosomes. They do not appear to contain lysosome-like bodies and represent less than 10% of the circulating hemocytes. Granulocytes are larger hemocytes which readily spread on glass surface and which strongly react to the Gomori substrate, indicating the enzyme acid phosphatase usually found in lysosomes. Ultra-structurally, they contain a well-developed rough endoplasmic reticulum, dictyosomes and some some lysosome-like dense bodies. Granulocytes do not exhibit a characteristic granular aspect and the few granules observed in the cytoplasm should correspond to a lysosome system. They were named granulocytes instead of amoebocytes to use the same terminology adopted for Biomphalaria glabrata in order to make easier comparative studies. This is a preface study for more specific investigations on the functional activities of the blood cells of B. tenagophila and their interactions with the trematode parasite.

  19. 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.

  20. New polymeric formulation for control of biomphalaria Alexandria based on pharmaceutical waste gelatin

    International Nuclear Information System (INIS)

    In the recent years, important new areas of application for plastics have emerged in medicine such as devices for the controlled release of drugs. The increases in the use of plastic materials in all sectors of industry have led to a continuous increase in the generation of plastic wastes. Recycling allow the waste to be reintroduced into the consumption cycle. Pharmaceutical companies which manufacture soft gels with different shapes, sizes and colors based mainly on gelatin formulations produce huge amount of gelatin waste. Schistosomiasis is one of the most important public health problems in our country. We now report the utilization of gelatin scrap by incorporating them in biodegradable films containing the molluscicide niclosamide for control of Biomphalaria Alexandrina snails. The preparation of the gelatin films will be described. The release of niclosamide from the prepared blends was investigated. The prepared formulations proved to be useful compared with free niclosamide

  1. Measurement of Selected Enzymatic Activities in Solanum nigrum-Treated Biomphalaria arabica Snails

    Science.gov (United States)

    Al-Daihan, Sooad

    In the present study, glucose, acid and alkaline phosphatases (ACP and ALP), α-amylase and lipase were measured for the first time in tissue homogenates of Biomphalaria arabica snails, molluscan intermediate host for Schistosoma mansoni in Saudi Arabia. Also, the effect of sublethal concentrations (LC25) of dry powdered Solanum nigrum leaf was tested as plant molluscicide against this snail species. The tested enzymes were altered in molluscicide-treated snails compared to control. While ALP and amylase were slightly affected, ACP and lipase were significantly altered. Glucose as an important energy source for a successful schistosome-snail relationship was significantly reduced in molluscicide-treated snails. In conclusion, sublethal concentration of the molluscicide showed potent effect in disturbing snail biochemistry which may render them physiologically unsuitable for the developing of schistosome parasite. This could be considered as a promising strategy to control the disease.

  2. 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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. PMID:27605788

  5. 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

    Directory of Open Access Journals (Sweden)

    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

  6. 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

    OpenAIRE

    P. Jurberg; J. V. Barbosa; Rotenberg, L.

    1988-01-01

    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 ...

  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

    Directory of Open Access Journals (Sweden)

    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. Carbohydrate metabolism alterations in Biomphalaria glabrata infected with Schistosoma mansoni and exposed to Euphorbia splendens var. hislopii latex

    OpenAIRE

    Clélia Christina Mello-Silva; Mônica Magno Vilar; Maurício Carvalho Vasconcellos; Jairo Pinheiro; Maria de Lurdes de A Rodrigues

    2010-01-01

    This paper evaluates the alterations in the glycogen content of tissues (digestive gland and cephalopedal mass) and glucose in the haemolymph of Biomphalaria glabrata BH strain infected with Schistosoma mansoni BH strain and exposed to the latex of Euphorbia splendens var. hislopii. A reduction in the glycogen deposits was observed in infected snails exposed and not exposed to latex. However, the exposure to latex caused a greater depletion of the glycogen levels in both sites analysed, espec...

  9. Rheotaxis of Biomphalaria glabrata on vertical substrates and its role in the recolonization of habitats treated with molluscicides

    OpenAIRE

    P. Jurberg; C. L. P. A. Coelho da Silva; M. G. M. Barreto; Soares, M. S.

    1988-01-01

    The authors observed specimens of Biomphalaria glabrata climbing up the vertical wall of a ditch against the current. The snails that showed this behavior during application of a molluscicide in the breeding site survived and probably played a role in repopulation, which was observed three months later. These observations motivated field and laboratory investigations which led the authors to conclude that: a) this species is able to climb vertical surfaces both in field and laboratory situati...

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

    OpenAIRE

    José Augusto A dos Santos; Therezinha Coelho B Tomassini; Deise Cristina Drummond Xavier; Ivone Maria Ribeiro; Melissa Teixeira G da Silva; Zenildo Buarque de Morais Filho

    2003-01-01

    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 physalin...

  11. Controlled chaos of polymorphic mucins in a metazoan parasite (Schistosoma mansoni) interacting with its invertebrate host (Biomphalaria glabrata).

    OpenAIRE

    Emmanuel Roger; Christoph Grunau; Pierce, Raymond J.; Hirohisa Hirai; Benjamin Gourbal; Richard Galinier; Rémi Emans; Cesari, Italo M.; Céline Cosseau; Guillaume Mitta

    2008-01-01

    International audience Invertebrates were long thought to possess only a simple, effective and hence non-adaptive defence system against microbial and parasitic attacks. However, recent studies have shown that invertebrate immunity also relies on immune receptors that diversify (e.g. in echinoderms, insects and mollusks (Biomphalaria glabrata)). Apparently, individual or population-based polymorphism-generating mechanisms exists that permit the survival of invertebrate species exposed to p...

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

    Directory of Open Access Journals (Sweden)

    Mohamed R Habib

    Full Text Available 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.

  13. 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.

  14. Gamma 60Co DL50/30 of Biomphalaria glabrata (Say, 1818 DL50/30 raios gama de 60Co em Biomphalaria glabrata (Say, 1818

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    Elaine Barros da Costa CARVALHO

    1999-11-01

    Full Text Available The variation of resistance to 60Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose to increasing doses of gamma radiation. Doses of 10, 20, 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell 60Co irradiator, were applied to the test groups and two groups control (non-irradiated of snails - isolated and colony - were kept apart. After have been exposed, the snails were drew back to the aquaria where they were maintained before. The survival was estimated on a daily score of the alive animals in each group-dose, starting after the irradiation exposure day. As a result, the survival self-fertilization forms (DL50/30 = 218.2 Gy was found greater than in cross-fecundation forms. These data point to a low radio-resistance on the cross-fertilization forms - the sexual reproductive form - which is most found in nature. The lower radio-resistance of the cross-fertilization forms suggests the presence of some sex-linked hormonal factor related to this phenomenon.A variação da resistência entre indivíduos em autofecundação e fecundação cruzada de Biomphalaria glabrata foram estudadas. Uma população de 480 moluscos foi observada durante 29 dias, distribuída em 8 grupos de caramujos isolados e 8 grupos em colônias após a exposição (30 caramujos por grupo-dose a doses crescentes de radiação gama. Foram usadas doses de 10, 20, 40, 60, 80, 160, 320 e 640 Gy de um irradiador Gamma-Cell 60Co. Dois grupos não irradiados - isolado e colônia - foram separados como controle e após a irradiação todos os caramujos voltaram para aquários onde viviam antes. A sobrevida foi estimada pela contagem diária dos animais vivos em cada grupo-dose, a partir do dia da irradiação. O resultado mostrou maior sobrevivência nos grupos isolados (DL50/30 = 218.2 Gy que nos grupos

  15. 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.

  16. 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

    Directory of Open Access Journals (Sweden)

    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.

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

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    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.

  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. 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.

  20. A Novel Bacterial Pathogen of Biomphalaria glabrata: A Potential Weapon for Schistosomiasis Control?

    Science.gov (United States)

    Duval, David; Galinier, Richard; Mouahid, Gabriel; Toulza, Eve; Allienne, Jean François; Portela, Julien; Calvayrac, Christophe; Rognon, Anne; Arancibia, Nathalie; Mitta, Guillaume; Théron, André; Gourbal, Benjamin

    2015-01-01

    Background 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. Methodology/Principal findings 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. Conclusions/Significance 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. PMID:25719489

  1. Ecotoxicological effect of sublethal exposure to zinc oxide nanoparticles on freshwater snail Biomphalaria alexandrina.

    Science.gov (United States)

    Fahmy, Sohair R; Abdel-Ghaffar, Fathy; Bakry, Fayez A; Sayed, Dawlat A

    2014-08-01

    Freshwater snails are used as sensitive biomarkers of aquatic ecosystem pollution. The potential impacts of zinc oxide nanoparticles (ZnONPs) on aquatic ecosystems have attracted special attention due to their unique properties. The present investigation was designed to evaluate the possible mechanisms of ecotoxicological effects of ZnONPs on freshwater snail Biomphalaria alexandrina. ZnONPs showed molluscicidal activity against B. alexandrina snails, and the LC50 was 145 μg/ml. Two tested concentrations of ZnONPs were selected: The first concentration was equivalent to LC10 (7 μg/ml), and the second was equivalent to LC25 (35 μg/ml). Exposure to ZnONPs (7 and 35 μg/ml) for three consecutive weeks significantly induced malondialdehyde and nitric oxide with concomitant decreases in glutathione and glutathione-S-transferase levels in hemolymph and soft tissues of treated snails. Moreover, ZnONPs elicited a significant decrease in total protein and albumin contents coinciding with enhancement of total lipids and cholesterol levels as well as activities of aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase in hemolymph and soft tissues of treated snails. This study highlights the potential ecological implications of ZnONP release in aquatic environments and may serve to encourage regulatory agencies in Egypt to more carefully monitor and regulate the industrial use and disposal of ZnONPs. PMID:24736985

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

    International Nuclear Information System (INIS)

    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 60Co 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 LD50 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)

  3. 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

  4. Sequencing of simple sequence repeat anchored polymerase chain reaction amplification products of Biomphalaria glabrata

    Directory of Open Access Journals (Sweden)

    Caldeira Roberta L

    2002-01-01

    Full Text Available Simple sequence repeat anchored polymerase chain reaction amplification (SSR-PCR is a genetic typing technique based on primers anchored at the 5' or 3' ends of microsatellites, at high primer annealing temperatures. This technique has already been used in studies of genetic variability of several organisms, using different primer designs. In order to conduct a detailed study of the SSR-PCR genomic targets, we cloned and sequenced 20 unique amplification products of two commonly used primers, CAA(CT6 and (CA8RY, using Biomphalaria glabrata genomic DNA as template. The sequences obtained were novel B. glabrata genomic sequences. It was observed that 15 clones contained microsatellites between priming sites. Out of 40 clones, seven contained complex sequence repetitions. One of the repeats that appeared in six of the amplified fragments generated a single band in Southern analysis, indicating that the sequence was not widespread in the genome. Most of the annealing sites for the CAA(CT6 primer contained only the six repeats found within the primer sequence. In conclusion, SSR-PCR is a useful genotyping technique. However, the premise of the SSR-PCR technique, verified with the CAA(CT6 primer, could not be supported since the amplification products did not result necessarily from microsatellite loci amplification.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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

  7. 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.

  8. 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)

  9. Differential gene expression in haemocytes of the snail Biomphalaria glabrata: effects of Schistosoma mansoni infection.

    Science.gov (United States)

    Miller, A N; Raghavan, N; FitzGerald, P C; Lewis, F A; Knight, M

    2001-05-15

    Parasite encapsulation and destruction in Biomphalaria glabrata has been shown to involve the cellular component of the snail's internal defence system, the haemocytes. To identify genes involved in the immunobiology of these cells, we used the method of differential display reverse transcriptase polymerase chain reaction (DDRT-PCR) to investigate differential gene regulation in haemocytes isolated from Schistosoma mansoni exposed and unexposed snails. RNA isolated from circulating haemocytes from resistant snails (BS-90 stock), previously exposed to S. mansoni, was analysed using 12 different arbitrary primers in conjunction with an anchored Oligo d(T(11)CG) primer. Transcription profiles between haemocytes of parasite exposed and unexposed snails were compared and a total of 87 differentially regulated bands were identified and isolated. Of these, 65 bands were cloned and used as probes in Southern blots to show the presence of corresponding sequences in the snail genome. RT-PCR was performed to verify the regulation of these transcripts. DNA sequence analysis showed that the majority of the cloned sequences were novel, although a few showed a high degree of sequence similarity to other sequences in the DNA and protein databases. One of these included a differentially expressed transcript that showed a significant degree of sequence identity to E. coli transposase Tn5, an enzyme whose activity is normally associated with generating mobility and instability in the genome. PMID:11336750

  10. Gamma {sup 60} Co D L {sub 50/30} of Biomphalaria glabrata (Say, 1818)

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Elaine Barros da Costa; Melo, Ana Maria Mendonca de Albuquerque; Motta, Mauricy Alves da [Pernambuco Univ., Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia

    1999-12-01

    The variation of resistance to {sup 60} Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose) to increasing doses of gamma radiation. Doses of 10, 20 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell {sup 60} Co irradiator, were applied to the test groups and two groups control (non-irradiated) of snails - isolated and colony - were kept apart. After have been exposed, the snails were drew back to the aquaria where they were maintained before. The survival was estimated on a daily score of the alive animals in each group-dose, starting after the irradiation exposure day. As a result, the survival self-fertilization forms (DL{sub 50/30}=218.2 Gy) was found greater than in cross-fecundation forms. These data point to allow radio-resistance on the cross-fertilization forms - the sexual reproductive form - which is most found in nature. The lower radio-resistance of the cross-fertilization forms suggests the presence of some sex-linked hormonal factor related to this phenomenon. (author)

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

    Directory of Open Access Journals (Sweden)

    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.

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

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    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.

  13. Gamma 60 Co D L 50/30 of Biomphalaria glabrata (Say, 1818)

    International Nuclear Information System (INIS)

    The variation of resistance to 60 Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose) to increasing doses of gamma radiation. Doses of 10, 20 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell 60 Co irradiator, were applied to the test groups and two groups control (non-irradiated) of snails - isolated and colony - were kept apart. After have been exposed, the snails were drew back to the aquaria where they were maintained before. The survival was estimated on a daily score of the alive animals in each group-dose, starting after the irradiation exposure day. As a result, the survival self-fertilization forms (DL50/30=218.2 Gy) was found greater than in cross-fecundation forms. These data point to allow radio-resistance on the cross-fertilization forms - the sexual reproductive form - which is most found in nature. The lower radio-resistance of the cross-fertilization forms suggests the presence of some sex-linked hormonal factor related to this phenomenon. (author)

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Ecology of bacterial communities in the schistosomiasis vector snailBiomphalaria glabrata.

    Science.gov (United States)

    Ducklow, H W; Clausen, K; Mitchell, R

    1981-09-01

    The internal colony-forming bacterial flora of the schistosome intermediate host snailBiomphalaria glabrata (Say) has been characterized in ca. 500 individual snails from Puerto Rico, Guadeloupe, and St. Lucia, and from laboratory aquaria. Freshly captured wild snails harbor 2-40×10(6) CFU·g(-1), and healthy aquarium snails harbor 4-16×10(7) CFU·g(-1), whereas moribund individuals have 4-10 times as many bacteria as healthy individuals from the same habitats.Pseudomonas spp. are the most common predominant bacteria in normal snails, whereasAcinetobacter, Aeromonas, andMoraxella spp. predominate in moribund snails. External bacterial populations in water appear to have little effect on the composition and size of the flora in any snail. In addition to normal (healthy) and moribund snails, a third group of snails has been distinguished on the basis of internal bacterial density and predominating genera. These "high-density" snails may have undergone stresses and may harbor opportunistic pathogens. The microfloras of wild and laboratory-reared snails can be altered and stimulated to increase in density by crowding the snails or treating them with antibiotics. PMID:24227500

  16. 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)

  17. 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.

  18. Carbohydrate metabolism alterations in Biomphalaria glabrata infected with Schistosoma mansoni and exposed to Euphorbia splendens var. hislopii latex

    Directory of Open Access Journals (Sweden)

    Clélia Christina Mello-Silva

    2010-07-01

    Full Text Available This paper evaluates the alterations in the glycogen content of tissues (digestive gland and cephalopedal mass and glucose in the haemolymph of Biomphalaria glabrata BH strain infected with Schistosoma mansoni BH strain and exposed to the latex of Euphorbia splendens var. hislopii. A reduction in the glycogen deposits was observed in infected snails exposed and not exposed to latex. However, the exposure to latex caused a greater depletion of the glycogen levels in both sites analysed, especially from the third week onward. The utilisation of latex as a molluscicide to control the population of infected B. glabrata selectively is proposed.

  19. Molluscicide activity of the "Avelós" plant (Euphorbia tirucalli, L. ) on Biomphalaria glabrata, the mollusc vector of schistosomiasis

    OpenAIRE

    Pedro Jurberg; Januário Bispo Cabral Neto; Virgínia T. Schall

    1985-01-01

    An aqueous solution of the latex of Euphorbia tirucalli collected at sites receiving large amounts of sunlight showed molluscicide action on Biomphalaria glabrata, with LD50 obtained at the concentration of 28,0 ppm and LD90 at the concentration of 85,0 ppm. The toxicity of the product for fish was similar to that of Bayluscide and of copper sulfate used for comparison. However, the wide distribution of the plant, its easy propagation and the simple procedure for extraction of the active subs...

  20. 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.

  1. Schistosomiasis control using piplartine against Biomphalaria glabrata at different developmental stages.

    Directory of Open Access Journals (Sweden)

    Ludmila Nakamura Rapado

    Full Text Available BACKGROUND: Schistosomiasis is one of the most significant diseases in tropical countries and affects almost 200 million people worldwide. The application of molluscicides to eliminate the parasite's intermediate host, Biomphalaria glabrata, from infected water supplies is one strategy currently being used to control the disease. Previous studies have shown a potent molluscicidal activity of crude extracts from Piper species, with extracts from Piper tuberculatum being among the most active. METHODS AND FINDINGS: The molluscicidal activity of P. tuberculatum was monitored on methanolic extracts from different organs (roots, leaves, fruit and stems. The compounds responsible for the molluscicidal activity were identified using (1H NMR and ESIMS data and multivariate analyses, including principal component analysis and partial least squares. These results indicated that the high molluscicidal activity displayed by root extracts (LC50 20.28 µg/ml was due to the presence of piplartine, a well-known biologically-active amide. Piplartine was isolated from P. tuberculatum root extracts, and the molluscicidal activity of this compound on adults and embryos of B. glabrata was determined. The compound displayed potent activity against all developmental stages of B. glabrata. Next, the environmental toxicity of piplartine was evaluated using the microcrustacean Daphnia similis (LC50 7.32 µg/ml and the fish Danio rerio (1.69 µg/ml. The toxicity to these organisms was less compared with the toxicity of niclosamide, a commercial molluscicide. CONCLUSIONS: The development of a new, natural molluscicide is highly desirable, particularly because the commercially available molluscicide niclosamide is highly toxic to some organisms in the environment (LC50 0.25 µg/ml to D. similis and 0.12 µg/ml to D. rerio. Thus, piplartine is a potential candidate for a natural molluscicide that has been extracted from a tropical plant species and showed less toxic to

  2. Schistosomiasis Control Using Piplartine against Biomphalaria glabrata at Different Developmental Stages

    Science.gov (United States)

    Rapado, Ludmila Nakamura; Pinheiro, Alessandro de Sá; Lopes, Priscila Orechio de Moraes Victor; Fokoue, Harold Hilarion; Scotti, Marcus Tullius; Marques, Joaquim Vogt; Ohlweiler, Fernanda Pires; Borrely, Sueli Ivone; Pereira, Carlos Alberto de Bragança; Kato, Massuo Jorge; Nakano, Eliana; Yamaguchi, Lydia Fumiko

    2013-01-01

    Background Schistosomiasis is one of the most significant diseases in tropical countries and affects almost 200 million people worldwide. The application of molluscicides to eliminate the parasite's intermediate host, Biomphalaria glabrata, from infected water supplies is one strategy currently being used to control the disease. Previous studies have shown a potent molluscicidal activity of crude extracts from Piper species, with extracts from Piper tuberculatum being among the most active. Methods and Findings The molluscicidal activity of P. tuberculatum was monitored on methanolic extracts from different organs (roots, leaves, fruit and stems). The compounds responsible for the molluscicidal activity were identified using 1H NMR and ESIMS data and multivariate analyses, including principal component analysis and partial least squares. These results indicated that the high molluscicidal activity displayed by root extracts (LC50 20.28 µg/ml) was due to the presence of piplartine, a well-known biologically-active amide. Piplartine was isolated from P. tuberculatum root extracts, and the molluscicidal activity of this compound on adults and embryos of B. glabrata was determined. The compound displayed potent activity against all developmental stages of B. glabrata. Next, the environmental toxicity of piplartine was evaluated using the microcrustacean Daphnia similis (LC50 7.32 µg/ml) and the fish Danio rerio (1.69 µg/ml). The toxicity to these organisms was less compared with the toxicity of niclosamide, a commercial molluscicide. Conclusions The development of a new, natural molluscicide is highly desirable, particularly because the commercially available molluscicide niclosamide is highly toxic to some organisms in the environment (LC50 0.25 µg/ml to D. similis and 0.12 µg/ml to D. rerio). Thus, piplartine is a potential candidate for a natural molluscicide that has been extracted from a tropical plant species and showed less toxic to environment. PMID

  3. Usnic Acid Potassium Salt: An Alternative for the Control of Biomphalaria glabrata (Say, 1818)

    Science.gov (United States)

    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. PMID:25375098

  4. 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.

  5. Differential spatial repositioning of activated genes in Biomphalaria glabrata snails infected with Schistosoma mansoni.

    Science.gov (United States)

    Arican-Goktas, Halime D; Ittiprasert, Wannaporn; Bridger, Joanna M; Knight, Matty

    2014-09-01

    Schistosomiasis is an infectious disease infecting mammals as the definitive host and fresh water snails as the intermediate host. Understanding the molecular and biochemical relationship between the causative schistosome parasite and its hosts will be key to understanding and ultimately treating and/or eradicating the disease. There is increasing evidence that pathogens that have co-evolved with their hosts can manipulate their hosts' behaviour at various levels to augment an infection. Bacteria, for example, can induce beneficial chromatin remodelling of the host genome. We have previously shown in vitro that Biomphalaria glabrata embryonic cells co-cultured with schistosome miracidia display genes changing their nuclear location and becoming up-regulated. This also happens in vivo in live intact snails, where early exposure to miracidia also elicits non-random repositioning of genes. We reveal differences in the nuclear repositioning between the response of parasite susceptible snails as compared to resistant snails and with normal or live, attenuated parasites. Interestingly, the stress response gene heat shock protein (Hsp) 70 is only repositioned and then up-regulated in susceptible snails with the normal parasite. This movement and change in gene expression seems to be controlled by the parasite. Other differences in the behaviour of genes support the view that some genes are responding to tissue damage, for example the ferritin genes move and are up-regulated whether the snails are either susceptible or resistant and upon exposure to either normal or attenuated parasite. This is the first time host genome reorganisation has been seen in a parasitic host and only the second time for any pathogen. We believe that the parasite elicits a spatio-epigenetic reorganisation of the host genome to induce favourable gene expression for itself and this might represent a fundamental mechanism present in the human host infected with schistosome cercariae as well as in

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

    Directory of Open Access Journals (Sweden)

    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.

  7. 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.

  8. 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).

  9. 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. PMID:24215068

  10. The nuclear receptors of Biomphalaria glabrata and Lottia gigantea: implications for developing new model organisms.

    Directory of Open Access Journals (Sweden)

    Satwant Kaur

    Full Text Available Nuclear receptors (NRs are transcription regulators involved in an array of diverse physiological functions including key roles in endocrine and metabolic function. The aim of this study was to identify nuclear receptors in the fully sequenced genome of the gastropod snail, Biomphalaria glabrata, intermediate host for Schistosoma mansoni and compare these to known vertebrate NRs, with a view to assessing the snail's potential as a invertebrate model organism for endocrine function, both as a prospective new test organism and to elucidate the fundamental genetic and mechanistic causes of disease. For comparative purposes, the genome of a second gastropod, the owl limpet, Lottia gigantea was also investigated for nuclear receptors. Thirty-nine and thirty-three putative NRs were identified from the B. glabrata and L. gigantea genomes respectively, based on the presence of a conserved DNA-binding domain and/or ligand-binding domain. Nuclear receptor transcript expression was confirmed and sequences were subjected to a comparative phylogenetic analysis, which demonstrated that these molluscs have representatives of all the major NR subfamilies (1-6. Many of the identified NRs are conserved between vertebrates and invertebrates, however differences exist, most notably, the absence of receptors of Group 3C, which includes some of the vertebrate endocrine hormone targets. The mollusc genomes also contain NR homologues that are present in insects and nematodes but not in vertebrates, such as Group 1J (HR48/DAF12/HR96. The identification of many shared receptors between humans and molluscs indicates the potential for molluscs as model organisms; however the absence of several steroid hormone receptors indicates snail endocrine systems are fundamentally different.

  11. 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. PMID:25867917

  12. 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.

  13. 3D-ultrastructure, functions and stress responses of gastropod (Biomphalaria glabrata rhogocytes.

    Directory of Open Access Journals (Sweden)

    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

  14. Molluscicide activity of the "Avelós" plant (Euphorbia tirucalli, L. on Biomphalaria glabrata, the mollusc vector of schistosomiasis

    Directory of Open Access Journals (Sweden)

    Pedro Jurberg

    1985-12-01

    Full Text Available An aqueous solution of the latex of Euphorbia tirucalli collected at sites receiving large amounts of sunlight showed molluscicide action on Biomphalaria glabrata, with LD50 obtained at the concentration of 28,0 ppm and LD90 at the concentration of 85,0 ppm. The toxicity of the product for fish was similar to that of Bayluscide and of copper sulfate used for comparison. However, the wide distribution of the plant, its easy propagation and the simple procedure for extraction of the active substance, which is biodegradable, favor "avelós" as a promising agent in the control of schistosomiasis.Uma solução aquosa de Euphorbia tirucalli (avelós coletada em locais ensolarados mostrou atividade moluscicida para Biomphalaria glabrata obtendo-se a LD50 a uma concentração de 28,0 ppm e a LD90 a 85,0 ppm. A toxicidade do produto para peixes foi similar a de Bayluscide e sulfato de cobre testados comparativamente. Pela larga distribuição da planta e sua fácil propagação e extração da substância ativa, e pela ausência de efeito residual, a planta pode ser considerada como promissora para testes de campo em locais restritos.

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

    International Nuclear Information System (INIS)

    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 60Co (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 χ2. 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)

  16. 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)

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

    Directory of Open Access Journals (Sweden)

    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

  18. Circulating Biomphalaria glabrata hemocyte subpopulations possess shared schistosome glycans and receptors capable of binding larval glycoconjugates.

    Science.gov (United States)

    Yoshino, Timothy P; Wu, Xiao-Jun; Gonzalez, Laura A; Hokke, Cornelis H

    2013-01-01

    Host lectin-like recognition molecules may play an important role in innate resistance in Biomphalaria glabrata snails to larval schistosome infection, thus implicating parasite-expressed glycans as putative ligands for these lectin receptors. While host lectins may utilize specific glycan structures for parasite recognition, it also has been hypothesized that the parasite may use this system to evade immune detection by mimicking naturally-expressed host glycans, resulting in reduced immunorecognition capacity. By employing immunocytochemical (ICC) and Western blot assays using schistosome glycan-specific monoclonal antibodies (mABs) we sought to identify specific glycan epitopes (glycotopes) shared in common between larval Schistosoma mansoni and B. glabrata hemocytes, the primary immune effector cells in snails. Results confirmed the presence of selected larval glycotopes on subpopulations of hemocytes by ICC and association with numerous hemocyte proteins by Western blot analyses, including a trimannosyl core N-glycan (TriMan), and two fucosylated lacdiNAc (LDN) variants, F-LDN and F-LDN-F. Snail strain differences were seen in the prevalence of constitutively expressed F-LDN on hemocytes, and in the patterns of protein immunoreactivity with these mABs. In contrast, there was little to no hemocyte reactivity with mABs for Lewis X (LeX), LDN, LDN-F or LDN-DF. When intact hemocytes were exposed to larval transformation products (LTPs), distinct cell subpopulations displayed weak (LeX, LDN-DF) to moderate (LDN, LDN-F) glycotope reactivity by ICC, including snail strain differences in the prevalence of LDN-reactive cellular subsets. Far-Western blot analyses of the hemocytes following exposure to larval transformation proteins (LTPs) also revealed multiple mAB-reactive hemocyte protein bands for LeX, LDN, LDN-F, and LDN-DF. These results demonstrate the existence of complex patterns of shared larval glycan constitutively expressed on hemocytes and their proteins

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

    Directory of Open Access Journals (Sweden)

    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.

  20. 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.

  1. 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)

  2. Dominant lethal effect of gamma radiation of 60Co in Biomphalaria glabrata (SAY, 1818)

    International Nuclear Information System (INIS)

    Germ cell mutations are used in ecotoxicological studies as biomarkers of population effects and indicators of ecological changes. Biomphalaria glabrata, a freshwater mollusk, is a good experimental model for biomonitoring studies due to its biological characteristics and the ecological importance of this invertebrate group. The dominant lethal test was established in B. glabrata for the detection of germ cell mutations. Results with chemical mutagens showed that this system is efficient, specific and sensitive in the evaluation of germ cell mutations induced by reference mutagens. In this work, the dominant lethal effects of gamma radiation of 60Co were studied. A preliminary experiment was done to establish the dose range and to estimate the chronology of spermatogenesis in B. glabrata. This estimate is possible because of the uniformity in response to ionizing radiation between germ cells at homologous stages of spermatogenesis in widely different species. In general, pre-meiotic germ cells are less sensitive to the induction of lethal dominant mutations than post-meiotic cells. This effect can be attributed to: young gametogenic cells - mitotically active - have greater repair ability from sub-lethal DNA damage and there is a selective elimination of the damaged cells. In our system: induction of lethal dominant mutations causes an increase in the frequency of malformations and, cytotoxic effect is displayed as a reduction in the crossing rates. Total duration of spermatogenesis was estimated in approximately 36 days, with the following distribution of stages: 1 to 13 days - spermatogonia, 14 to 20 days - spermatocytes, 21 to 36 days - spermatids and spermatozoa. Based on this chronology, irradiated wild-type snails with 2,5; 10 and 20Gy and crossed with non-irradiated albino snails after 7, 17, 23, 30 and 36 days. The frequencies of malformations in the heterozygous wild-type offspring of the nonirradiated albino snails were used as indicator of germ cell

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

    OpenAIRE

    2002-01-01

    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. ...

  4. 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

    OpenAIRE

    Pedro Jurberg; Otília Sarquis; José Augusto A dos Santos; Regina da Conceição Reis Ferreira

    1995-01-01

    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 surviv...

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

    OpenAIRE

    Alexandre Giovanelli; Cesar Luiz Pinto Ayres Coelho da Silva; Luisa Medeiros; Maurício Carvalho Vasconcellos

    2001-01-01

    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 i...

  6. Effects of Varying Concentrations of the Crude Aqueous and Ethanolic Extracts of Dalbergia Sissoo Plant Parts on Biomphalaria Pfeifferi Egg Masses

    OpenAIRE

    Adenusi, Adedotun A; Odaibo, Alexander B

    2009-01-01

    This study evaluated, using replicated laboratory bioassays, the toxicities of the crude aqueous and ethanolic extracts of Dalbergia sissoo Roxb. 1832 (family Leguminosae) fruits, leaves, roots and stem bark against egg masses of Biomphalaria pfeifferi (Krauss, 1848), the snail intermediate host of Schistosoma mansoni (Sambon, 1907) in Nigeria. Viable 0–24 hr-old embryonated egg masses were separately exposed to five different concentrations (7.81–2000 mg/l) of extracts for 24 hrs, washed in ...

  7. Bases génétiques du polymorphisme de compatibilité dans l'interaction Schistosoma mansoni / Biomphalaria glabrata

    OpenAIRE

    Roger, Emmanuel

    2008-01-01

    The co-evolutionary dynamics that exist in certain invertebrate host / parasite interactions sometimes lead to a compatibility polymorphism, of which the molecular bases are unknown. To identify key molecules involved in this phenomenon in the Schistosoma mansoni / Biomphalaria glabrata model, we developed a comparative proteomics approach for the larval stages that interact with the invertebrate host. The qualitative and quantitative comparison of the proteomes of compatible and incompatible...

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Irrigation canals in Melo creek basin (Rio Espera and Capela Nova municipalities, Minas Gerais, Brazil): habitats to Biomphalaria (Gastropoda: Planorbidae) and potential spread of schistosomiasis.

    Science.gov (United States)

    Leite, M G P; Pimenta, E C; Fujaco, M A G; Eskinazi-Sant'Anna, E M

    2016-04-19

    This study analyzed the presence of Biomphalaria in Melo creek basin, Minas Gerais state, and its relationship to irrigation canals. Seventeen of these canals were used to determine a limnological, morphological and hydrological characterization during an annual seasonal cycle. Biomphalaria samples were sent to René Rachou Research Center/FIOCRUZ for identification and parasitological examination. Six canals were identified as breeding areas for mollusks and in one of them it was registered the coexistence of B. tenagophila (first report to this basin) and B. glabrata species. Results indicated that the low flow rate and speed of water flow were the main characteristics that contributed to this specific growth of the mollusks in the area. These hydraulic characteristics were created due to anthropogenic action through the canalization of lotic areas in Melo creek, which allowed ideal ecological conditions to Biomphalaria outbreak. The results emphasize the need of adequate handling and constant monitoring of the hydrographic basin, subject to inadequate phytosanitary conditions, aiming to prevent the occurrence and propagation of schistosomiasis. PMID:27097093

  10. Transmission of Schistosoma mansoni under experimental conditions using the bovine - Biomphalaria glabrata - bovine model Transmissão do Schistosoma mansoni em condições experimentais, usando o modelo bovino - Biomphalaria glabrata - bovino

    Directory of Open Access Journals (Sweden)

    Celina M. Modena

    1993-02-01

    Full Text Available Three calves experimentally infected with Schistosoma mansoni, and passing viable eggs in feces, as well as 5 normal calves (coming from a non-endemic area for schistosomiasis kept as controls, were maintained in an enclosure (850 m² in area. In this enclosure, a tank with water received 500 laboratory reared Biomphalaria glabrata. All the control calves were infected for a period ranging from 79 to 202 days after the beginning of the experiment, and afterwards presented viable S. mansoni eggs in feces. The mean worm recovery was 555. The snail population increased throughout the experimental period, showing a high number of B. glabrata infected with S. mansoni (42% on average. According to the present study, bovine has been suggested as having potentially a role in the maintenance of the life cycle of S. mansoniTrês bezerros, experimentalmente infectados com Schistosoma mansoni e passando ovos viáveis nas fezes, bem como 5 bezerros normais, oriundos de área não endêmica para esquistossomose e usados como controles, foram mantidos em uma área fechada de 850 m². Nesta área, foram colocados em um tanque com água 500 caramujos Biomphalaria glabrata criados em laboratório. Todos os bezerros controles foram infectados por um período de 79 a 202 dias após o começo do experimento e, mais tarde, apresentaram ovos viáveis de S. mansoni nas fezes. A recuperação média de vermes foi de 538. A população de moluscos aumentou durante o período experimental, mostrando um número significativo de B. glabrata infectados com S. mansoni (42% em média. De acordo com o resultado do presente trabalho, que foi conduzido em condições experimentais, foi sugerido que bovinos tem, potencialmente, um papel na manutenção do ciclo vital do S. mansoni

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

    Directory of Open Access Journals (Sweden)

    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.

  12. [Dynamic transmission of Schistosoma by Biomphalaria pfeifferi in the region of Man in Côte d'Ivoire].

    Science.gov (United States)

    Yapi Yapi, G; Touré, M; Boka, O M; Tia, E; Boby, O A-M

    2014-12-01

    Intestinal schistosomiasis by Schistosoma mansoni is a parasitary affection transmitted in West Africa by the mollusc Biomphalaria pfeifferi. Transmission dynamic of schistosomiasis by Biomphalaria pfeifferi has seldom been investigated in Côte d'Ivoire. In the framework of a research project on the epidemiology of schistosomiasis in the natural forest ecosystems, this study was performed longitudinally over a period of three years in Man region, in western Côte d'Ivoire. The trial set up from 1986 to 1989 and the project was funded by the World Health Organization. The general objective is to design a strategy of schistosomiasis control based on chemotherapy. The approach aims at interrupting or considerably reducing the reinfections, prolonging in that way the duration of the positive effects of the chemotherapy. The specific objectives assigned to the work consisted in studying the dynamic of the B. pfeifferi population and the infection of B. pfeifferi. To achieve our objectives, diverse methods (i: the molluscs sampling by two prospectors during 15 minutes per study site and ii: individual isolation of molluscs in test tubes with 5 or 10 mL of filtered water and exposure to light) have been used. They enabled us in the sampling of the intermediary host molluscs of Schistosoma and seek their infections. The results show that apparent high densities of B. pfeifferi can be observed at the end of the dry season and at the beginning of rainy seasons. In addition, the variation of relative abundance of intermediary host molluscs of Schistosoma is significantly influenced by rainfall and the system of water ways. The period of transmission of the infection to man is six months at Gueupleu village and ten months at Botonguiné village. In order to optimize the effect of chemotherapy in these sites of transmission characterized by a high level of endemy (68 %), an extreme mobility of human populations and a multiplicity of contamination sites, this study should not

  13. Epigenetic modulation, stress and plasticity in susceptibility of the snail host, Biomphalaria glabrata, to Schistosoma mansoni infection.

    Science.gov (United States)

    Knight, Matty; Ittiprasert, Wannaporn; Arican-Goktas, Halime D; Bridger, Joanna M

    2016-06-01

    Blood flukes are the causative agent of schistosomiasis - a major neglected tropical disease that remains endemic in numerous countries of the tropics and sub-tropics. During the past decade, a concerted effort has been made to control the spread of schistosomiasis, using a drug intervention program aimed at curtailing transmission. These efforts notwithstanding, schistosomiasis has re-emerged in southern Europe, raising concerns that global warming could contribute to the spread of this disease to higher latitude countries where transmission presently does not take place. Vaccines against schistosomiasis are not currently available and reducing transmission by drug intervention programs alone does not prevent reinfection in treated populations. These challenges have spurred awareness that new interventions to control schistosomiasis are needed, especially since the World Health Organization hopes to eradicate the disease by 2025. For one of the major species of human schistosomes, Schistosoma mansoni, the causative agent of hepatointestinal schistosomiasis in Africa and the Western Hemisphere, freshwater snails of the genus Biomphalaria serve as the obligate intermediate host of this parasite. To determine mechanisms that underlie parasitism by S. mansoni of Biomphalaria glabrata, which might be manipulated to block the development of intramolluscan larval stages of the parasite, we focused effort on the impact of schistosome infection on the epigenome of the snail. Results to date reveal a complex relationship, manifested by the ability of the schistosome to manipulate the snail genome, including the expression of specific genes. Notably, the parasite subverts the stress response of the host to ensure productive parasitism. Indeed, in isolates of B. glabrata native to central and South America, susceptible to infection with S. mansoni, the heat shock protein 70 (Bg-HSP70) gene of this snail is rapidly relocated in the nucleus and transcribed to express HSP70

  14. Aspectos histológicos das gônadas hermafroditas de Biomphalaria glabrata e Bradybaena similaris (Mollusca, Gastropoda, Pulmonata

    Directory of Open Access Journals (Sweden)

    Rinaldo Florêncio da Silva

    2009-01-01

    Full Text Available Biomphalaria glabrata (Say, 1818 é um gastrópode pulmonado de água doce que desperta grande interesse médico e veterinário. Bradybaena similaris (Férussac, 1821 é um gastrópode pulmonado terrestre considerado uma praga agrícola de plantações de hortaliças. Ambas as espécies são hospedeiras intermediárias de helmintos. Esses moluscos possuem uma gônada hermafrodita produtora de óvulos e espermatozóides de forma simultânea. Neste estudo foram avaliados aspectos histomorfológicos das gônadas hermafroditas de B. glabrata e B. similaris. A gônada de B. similaris encontra-se subdividida em lobos com glândulas em seu interior, o que não foi observado em B. glabrata. Além disso, em B. similaris as células germinativas estão acumuladas em determinados pontos e com a presença de um ovócito em cada folículo da gônada; não obstante, em B. glabrata as células germinativas encontraram-se justapostas e com mais de um ovócito em cada folículo.Biomphalaria glabrata (Say, 1818 is a freshwater pulmonate gastropod that represents great medical importance. Bradybaena similaris (Férussac, 1821 is a terrestrial pulmonate gastropod and an important plague to the different plant cultures with economic interest. Both species are intermediate hosts of helminths. These molluscs have hermaphrodites gonads producing eggs and sperm. Here, we examined histoformological aspects of hermaphrodites gonads of both B. glabrata and B. similaris. The gonad of B. similaris is subdivided into lobes and presence of glands in its interior, which was not observed in B. glabrata. Moreover, in B. similaris the germ cells are accumulated in some areas, and has one oocyte in each follicle in the gonad; however, in B. glabrata the germ cells are juxtaposed and more than one oocyte in each follicle.

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

    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.

  16. Evaluation of the molluscicidal potential of hydroalcoholic extracts of Jatropha gossypiifolia Linnaeus, 1753 on Biomphalaria glabrata (Say, 1818).

    Science.gov (United States)

    Pereira Filho, Adalberto Alves; França, Clícia Rosane Costa; Oliveira, Dorlam's da Silva; Mendes, Renato Juvino de Aragão; Gonçalves, José de Ribamar Santos; Rosa, Ivone Garros

    2014-01-01

    The action of extracts from the stem, leaves, and fruit of Jatropha gossypiifolia on Biomphalaria glabrata was studied by analyzing survival, feeding capacity and oviposition ability. The extracts were obtained by macerating the plant parts in 92% ethanol, which were then evaporated until a dry residue was obtained and phytochemically studied. The molluscicidal activity on B. glabrata was investigated using the procedures recommended by WHO (1965). The amount of food ingested and oviposition were measured during each experiment. The extract of leaves from J. gossypiifolia was shown to be a strong molluscicidal agent, causing 100% mortality of B. glabrata, even in the lowest concentration tested, of 25 ppm. Regarding the fruit extract, there was variation in the mortality, depending on the concentration used (100, 75, 50 and 25 ppm). The snails that were in contact with the fruit extract had significant reduction in feeding and number of embryos in comparison to the control. The stem extract did not present molluscicidal activity nor had any influence on the feeding and oviposition abilities of B. glabrata, in the concentrations tested. In conclusion, the extracts of leaves and fruits of J. gossypiifolia investigated in this work show molluscicidal effect and may be sources of useful compounds for the schistosomiasis control. PMID:25351545

  17. 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.

  18. 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.

  19. Correlation between steroid sex hormones, egg laying capacity and cercarial shedding in Biomphalaria alexandrina snails after treatment with Haplophyllum tuberculatum.

    Science.gov (United States)

    Rizk, Maha Z; Metwally, Nadia S; Hamed, Manal A; Mohamed, Azza M

    2012-10-01

    Schistosomiasis is considered the second most pre-valiant worldwide parasitic disease ranked next to malaria. It has significant economic and public health consequences in many developing countries. Several ways have been practiced in order to bring the disease under an adequate control through the breakage of the life cycle of the parasite. Snail control could be regarded as a rapid and efficient of reducing or eliminating transmission and remains among the methods of choice for schistosomiasis control. The aim of this work is to evaluate the role of Haplophyllum tuberculatum (family Rutaceae) as a plant molluscicide. The mortality rate of Biomphalaria alexandrina snails were monitored after treatment with three extracts of the plant aerial parts; petroleum ether, chloroform and ethanol. Chloroform extract that recorded the most potent effect was further evaluated through measuring the toxicity pattern against B. alexandrina snails, egg laying capacity, cercarial shedding, phenol oxidase enzyme and the levels of steroid sex hormones. Histopathological examination of hepatopancreas and ovotestis of treated snails were also done for result confirmation. Treatment of snails by chloroform extract recorded reduction in egg laying capacity, decrease in cercarial shedding, diminution in phenol oxidase enzyme, disturbance in steroid sex hormones and sever alternation of the histopathological picture of snails tissue. In conclusion, H. tuberculatum recorded molluscicidal potency against B. alexandrina snails. Further studies are needed for its environmental applications. PMID:22771439

  20. 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

  1. Sublethal Effects of Some New Textile Dyes On the Freshwater Snail Biomphalaria alexandrina, as a Biological Indicator

    International Nuclear Information System (INIS)

    The Eco toxicological effects of three synthetic textile dyes; fast violet (FV), fast orange (FO) and fast yellow (FY) which mainly used in textile industry in Egypt, were tested on the freshwater snail Biomphalaria alexandrina, that used as a bio-indicator. The results demonstrated that only the FV dye is lethal and the 72 hr LC 50 is 500 ppm. The FO and dyes did not show any lethal effect on the snails at the concentrations used throughout the experiment time. The sublethal toxic concentration of non-irradiated FV dye (100 ppm) showed an increase in cellular and humoral defense responses of the snails exposed to the dye for 72 hr. Although the profile of the snail's nucleoproteins revealed minor qualitative differences; were quantitative differences differences reflected in the intensity of the separated bands, as well as, the percentage of the protein content. The protein content significantly decreased in the snails exposed to FV-dye when compared to FO,FY and non-exposed control snails

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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. 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. PMID:25259848

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

    Directory of Open Access Journals (Sweden)

    C Edgardo Borda

    2007-03-01

    Full Text Available 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  7. 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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  9. 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

    Directory of Open Access Journals (Sweden)

    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

  10. 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

    Directory of Open Access Journals (Sweden)

    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

  11. Rheotaxis of Biomphalaria glabrata on vertical substrates and its role in the recolonization of habitats treated with molluscicides

    Directory of Open Access Journals (Sweden)

    P. Jurberg

    1988-06-01

    Full Text Available The authors observed specimens of Biomphalaria glabrata climbing up the vertical wall of a ditch against the current. The snails that showed this behavior during application of a molluscicide in the breeding site survived and probably played a role in repopulation, which was observed three months later. These observations motivated field and laboratory investigations which led the authors to conclude that: a this species is able to climb vertical surfaces both in field and laboratory situations; b the current of water, as a physical stimulus, is sufficient to trigger this behavior (rheotaxis; c rheotaxis on vertical surfaces depends on the presence of a necessarily moderate current; d there are indications that B. glabrata may undergo habituation with respect to rheotaxis on vertical walls, e the relationship between rheotaxis and habituation should be considered as a factor causing snail grouping in water bodies which may contribute to their localization in the field; f rheotaxis on vertical surfaces may facilitate population dispersal, and its occurrence should be considered when campaigns for the control of schistosomiasis transmission are planned. The authors present some proposals to avoid the manifestation of this behavior in some filed situations.Os autores observaram exemplares de Biomphalaria glabrata subindo contra corrente em uma parede vertical de uma vala, constatando que os caramujos que apresentavam esse comportamento durante a aplicação de miluscicida neste criadouro sobreviveram e, provavelmente, tiveram papel de repovoamento, que foi observado três meses após. Essas observações suscitaram investigações de campo e de laboratório, através das quais concluiram que: a esta espécie é capaz de subir em superfícies verticais em situações de campo e de laboratório; b a corrente da água enquanto estímulo físico, é suficiente para desencadear esse comportamento (reotaxia; c a reotaxia em superfícies verticais depende

  12. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  14. 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

    OpenAIRE

    Marco Antonio Vasconcelos Santos; José Antonio Picanço Diniz

    2009-01-01

    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 m...

  15. Molluscicidal Activity of the Methanol Extract of Callistemon viminalis (Sol. ex Gaertner) G.Don ex Loudon Fruits, Bark and Leaves against Biomphalaria alexandrina Snails

    Science.gov (United States)

    A Gohar, Ahmed; T Maatooq, Galal; R Gadara, Sahar; S Aboelmaaty, Walaa; M El-Shazly, Atef

    2014-01-01

    Methanol extracts of Callistemon viminalis (Sol. Ex Gaertner) G.Don Ex Loudon fruits, bark and leaves were tested for molluscicidal activity. Snails were collected and kept in dechlorinated water under standard condition. Ten adults Biomphalaria Alexandrina, of the same size, were introduced in plastic acquaria for each experiment. The fruits, barks and leaves were extracted with methanol and the methanol extracts were kept for testing as molluscicides. Different extracts proved to have molluscicidal activity against the vector of schistosomiasis, B. alexandrina snails. LC50 values for C. viminalis fruits, bark and leaves were 6.2, 32 and 40 ppm respectively. The C. viminalis fruits extract showed the highest effect against the tested snails. Histopathological studies proved that the site of action of all tested extracts was localized in the digestive system and hermaphrodite gland. PMID:25237345

  16. 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

    Directory of Open Access Journals (Sweden)

    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.

  17. 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

    Directory of Open Access Journals (Sweden)

    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

  18. A Comparative Study of the Organic Acid Content of the Hemolymph of Schistosoma mansoni-Resistant and Susceptible Strains of Biomphalaria glabrata

    Directory of Open Access Journals (Sweden)

    José Clecildo Barreto Bezerra

    1997-05-01

    Full Text Available The freshwater snail Biomphalaria glabrata is an intermediate host of the trematode Schistosoma mansoni. However, some strains of B. glabrata are resistant to successful infection by S. mansoni larvae. The present work examines the profile of organic acids present in S. mansoni-resistant and -susceptible strains of B. glabrata, in order to determine whether the type of organic acid present is related to susceptibility. The organic acids were extracted from the hemolymph of two susceptible B. glabrata strains (PR, Puerto Rico and Ba, Jacobina-Bahia from Brazil, and from the resistant strains 13-16-R1 and 10R2, using solid phase extraction procedures followed by high performance liquid chromatography. The organic acids obtained were analyzed and identified by comparison with known standards. Pyruvate, lactate, succinate, malate, fumarate, acetate, propionate, ß-hydroxybutyrate and acetoacetate were detected in all hemolymph samples. Under standard conditions, the concentration of each of these substances varied among the strains tested and appeared to be specific for each strain. An interesting variation was the low concentration of pyruvate in the hemolymph of PR-snails. Only the concentration of fumarate was consistently different (p£ 0.05 between resistant and susceptible strains

  19. Evaluation of the mitochondrial system in the gonad-digestive gland complex of Biomphalaria glabrata (Mollusca, Gastropoda) after infection by Echinostoma paraensei (Trematoda, Echinostomatidae).

    Science.gov (United States)

    Tunholi, Victor Menezes; Tunholi-Alves, Vinícius Menezes; Santos, Anderson Teixeira; Garcia, Juberlan da Silva; Maldonado, Arnaldo; da-Silva, Wagner Seixas; Rodrigues, Maria de Lurdes de Azevedo; Pinheiro, Jairo

    2016-05-01

    The effect of infection by Echinostoma paraensei on the mitochondrial physiology of Biomphalaria glabrata was investigated after exposure to 50 miracidia. The snails were dissected one, two, three and four weeks after infection for collection and mechanical permeabilization of the gonad-digestive gland (DGG) complex. The results obtained indicate that prepatent infection by this echinostomatid fluke significantly suppresses the phosphorylation state (respiratory state 3) and basal oxygen consumption of B. glabrata, demonstrating that the infection reduces the ability of the intermediate host to carry out aerobic oxidative reactions. Additionally, relevant variations related to the uncoupled mitochondrial (state 3u) of B. glabrata infected by E. paraensei were observed. Four weeks after exposure, a significant reduction in mitochondrial oxygen consumption after addition of ADP (3.68±0.26pmol O2/mg proteins) was observed in the infected snails in comparison with the respective control group (5.14±0.25). In the uncoupled state, the infected snails consumed about 62% less oxygen than the infected snails (7.87±0.84pmol O2/mg proteins) in the same period. These results demonstrate a reduction in oxidative decarboxylation rate of the tricarboxylic acid cycle and faster anaerobic degradation of carbohydrates in the infected snails. The possible mechanisms that explain this new metabolic condition in the infected organisms are discussed. PMID:27079167

  20. Effects of Plagiorchis elegans (Digenea: Plagiorchiidae) infection of Biomphalaria glabrata (Pulmonata: Planorbidae) on a challenge infection with Schistosoma mansoni (Digenea: Schistosomatidae).

    Science.gov (United States)

    Zakikhani, M; Smith, J M; Rau, M E

    2003-02-01

    Prior exposure of Biomphalaria glabrata to the eggs of an incompatible digenean, Plagiorchis elegans, rendered this snail host less suitable to a compatible species, Schistosoma mansoni. Although P. elegans failed to develop patent infections in B. glabrata, it reduced the production of S. mansoni cercariae by 88%. Concomitantly, host attributes such as reproduction, growth, and survival were compromised. The effect of P. elegans infection was most severe among snails that, in addition, had developed patent schistosome infections. Although few S. mansoni cercariae were produced, egg production by B. glabrata was only 4% of control values. Furthermore, no doubly infected snails survived for more than 3 wk after patency, whereas controls experienced no mortality during the same time period. The above effects were attributable to the establishment and persistence of P. elegans sporocysts in the tissues of the incompatible snail host. Their indirect antagonistic interaction with thelarval stages of S. mansoni may be mediated, in part, through their long-term stimulation of the host's internal defense mechanisms. These findings are discussed with a view to use P. elegans and other plagiorchiid digeneans as agents in the biological control of snails and snail-borne diseases. PMID:12659305

  1. 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.

  2. 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.

  3. 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.

  4. Study on Extraction of cpDNA from Endangered Medicinal Plant of Gentiana straminea Maxim . and Gentiana crassicaulis Duthie ex Burk%濒危药用植物麻花秦艽和粗茎秦艽cpDNA提取研究

    Institute of Scientific and Technical Information of China (English)

    高欢欢; 倪梁红; 胡志刚; 姚辉; 吴和珍; 潘宏林

    2013-01-01

    目的:对麻花秦艽和粗茎秦艽叶绿体基因组进行提取研究,为进一步研究秦艽叶绿体的基因组序列特征、遗传多样性以及资源保护研究奠定基础。方法:本文以麻花秦艽、粗茎秦艽为对象,采用改良的蔗糖密度梯度离心方法进行提取,优化纯化方法,分离得到秦艽叶绿体后测定cpDNA 浓度,检测其OD值并扩增ITS2序列验证其纯度。结果:获得高质量、高纯度的 cpDNA (0.1~0.4滋g/10 g),扩增ITS2序列验证其无核污染,满足后续测序要求。结论:cpDNA 的纯度和质量对叶绿体基因组测序的正确率和可信度具有重要的影响。本文获得了高纯度、高质量的秦艽cpDNA,为秦艽叶绿体基因组全序列的获得提供保障。%This study was aimed to show the extraction research of cpDNA in Gentiana straminea Maxim. and G. crassicaulis Duthie ex Burk., which will increase the knowledge about the chloroplast genome sequence characteris-tics, understand its genetic diversity and improve the efficiency of breeding schemes. G. straminea Maxim. and G. crassicaulis Duthie ex Burk. were taken as study objects. The improved sucrose-gradient centrifugation and purifica-tion methods were used to obtain the cpDNA, measure the concentration, detect the OD value, and amplify the ITS2 sequence to verify the nucleus pollution. The results showed that the high quality and purity cpDNA (0.1 - 0.4 μg/10 g) was demonstrated without other pollution after ITS2 sequence amplification, which met to the subsequent effi-cient sequencing of chloroplast genomes. The purity and mass have an important influence on the accuracy and cred-ibility of the cp genome sequencing. It was concluded that this study improved the sucrose-gradient centrifugation and purification with great effect of the purity and mass of cpDNA, and guaranteed the obtaining of complete cpDNA of Gentiana.

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

    Science.gov (United States)

    Zhang, Si-Ming; Buddenborg, Sarah K; Adema, Coen M; Sullivan, John T; 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 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 has been

  6. 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.

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

    Science.gov (United States)

    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. PMID:24215063

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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

  11. Colonização de Pomacea haustrum (Reeve, 1856 em localidade com esquistossomose mansoni: Baldim, MG (Brasil. (Prosobranchia, Pilidae Colonization of Pomacea haustrum (Reeve, 1856 at localility with Schistosomiasis mansoni: Baldim, MG (Brazil

    Directory of Open Access Journals (Sweden)

    Roberto Milward-de-Andrade

    1979-06-01

    Full Text Available Na localidade de Baldim, MG, Brasil, foram introduzidos, em agosto de 1972, 5.421 exemplares de Pomacea haustrum (Prosobranchia, Pilidae em 5 córregos e 2 valas, nos quais predominavam Biomphalaria glabrata (Say, 1818 e, secundariamente, B. straminea (Dunker, 1848. Entre 1968 e 1971, os índices de infecção da espécie B. glabrata por Schistosoma mansoni oscilaram de 2,1% a 11,9%. Em nenhum momento foram capturados B. straminea liberando cercárias daquele trematódeo. Após a introdução do pilídeo, apenas uma única vez detectou-se 2 (0,8% B. glabrata positivas. Observou-se decréscimo populacional de planorbineos e aumento de densidade de pomácea até 20,0 e 121,6 exemplares/m² em córregos e valas, respectivamente. A estimativa da densidade de F. haustrum foi feita através do método dos "quadrats". Foram coletados, de junho de 1968 a julho de 1972, 65,2% (1.526 dos planorbíneos. Porém, após a introdução do predador-competidor, foram registrados os seguintes dados: 1976, 15% (352; em 1977, 16,1% (377 e, em 1978, apenas 3,7% (87 do total dos exemplares capturados. As pomáceas, transferidas do ambiente lenítico (Sete Lagoas, MG, adaptaram-se às coleções lóticas de Baldim e foram capazes de substituir as populações originais de B. glabrata em vários biótopos, ou tornaram-se, pelo menos, dominantes, sem danos visíveis para os novos ecossistemas. Acredita-se que em outras situações análogas, Pomacea haustrum (Reeve, 1956 - e, por extensão, P. lineata (Spix, 1827, P. canaliculata (Lamark, 1822 e outras do mesmo táxon - poderão ser utilizadas, com sucesso, no controle biológico dos hospedeiros intermediários de Schistosoma mansoni.In the region of Baldim, MG (Brazil - a well-known Schistosoma mansoni endemic area where transmission control had already been unsuccessfully attempted through molluscicide, sanitary education and clinical treatment - 5,421 specimens of Pomacea haustrum (Prosobranchia, Pilidae were

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

    Directory of Open Access Journals (Sweden)

    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

  13. Estudos preliminares com bromoacetamida, um novo moluscicida

    OpenAIRE

    Naftale Katz; Cecília P. de Souza; Neusa Araújo

    1985-01-01

    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 c...

  14. Aspectos físico-químicos e biológicos relacionados à ocorrência de Biomphalaria glabrata em focos litorâneos da esquistossomose em Pernambuco

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    Petronildo Bezerra da Silva

    2006-10-01

    Full Text Available This study analyzes the physico-chemical and biological parameters of freshwater aquatic environments in coastal areas of the State of Pernambuco, Brazil, where snail vector foci and cases of schistosomiasis have been recorded. The tests were carried out using standard methods and sediments were analyzed using the X-ray fluorescence technique. The micro-algae were analyzed using conventional microscopy. The most abundant chemical elements in the sediments were Fe, Ca, Si and Al and there were high concentrations of electrolytes in comparison with data published in the literature. The mean values for salinity (7.7 g/L and sulfate (489 mg/L were much higher than normal for freshwater environments. The micro-algae identified are those that inhabit environments with higher levels of salinity. The snail Biomphalaria glabrata seems, therefore, to be more tolerant to salty environments and this constitutes a risk of spread of schistosomiasis.

  15. Aspectos físico-químicos e biológicos relacionados à ocorrência de Biomphalaria glabrata em focos litorâneos da esquistossomose em Pernambuco

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    Silva Petronildo Bezerra da

    2006-01-01

    Full Text Available This study analyzes the physico-chemical and biological parameters of freshwater aquatic environments in coastal areas of the State of Pernambuco, Brazil, where snail vector foci and cases of schistosomiasis have been recorded. The tests were carried out using standard methods and sediments were analyzed using the X-ray fluorescence technique. The micro-algae were analyzed using conventional microscopy. The most abundant chemical elements in the sediments were Fe, Ca, Si and Al and there were high concentrations of electrolytes in comparison with data published in the literature. The mean values for salinity (7.7 g/L and sulfate (489 mg/L were much higher than normal for freshwater environments. The micro-algae identified are those that inhabit environments with higher levels of salinity. The snail Biomphalaria glabrata seems, therefore, to be more tolerant to salty environments and this constitutes a risk of spread of schistosomiasis.

  16. 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.

  17. 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

    OpenAIRE

    Cecília Pereira de Souza; Nelymar Martineli Mendes; Liana Konovaloff Jannotti-Passos; José Pedro Pereira

    1992-01-01

    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 concentra...

  18. Ensaios preliminares do Guaiacum officinale L. como moluscicida Preliminary tests of Guaiacum officinale L. as molluscicide

    OpenAIRE

    Nelymar Martineli Mendes; José D. Gómez; Neusa Araújo; Carlos Leomar Zani; Naftale Katz

    1993-01-01

    Suspensões aquosas do pericarpo do fruto, da casca da raiz, das folhas e das sementes de Guaiacum officinale foram testadas como moluscicida, cercaricida e piscicida em diferentes concentrações. Em laboratório, a suspensão do pericarpo do fruto apresentou 100% de mortalidade a 100 ppm para desovas de B. glabrata, a 20 ppm para caramujos adultos de Biomphalaria glabrata, B. straminea e B. tenagophila, a 5 ppm para Lebistes reticulatus (peixes) e a 1 ppm para cercárias de Schistosoma mansoni. O...

  19. 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.

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Ensaios preliminares do Guaiacum officinale L. como moluscicida Preliminary tests of Guaiacum officinale L. as molluscicide

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    Nelymar Martineli Mendes

    1993-12-01

    Full Text Available Suspensões aquosas do pericarpo do fruto, da casca da raiz, das folhas e das sementes de Guaiacum officinale foram testadas como moluscicida, cercaricida e piscicida em diferentes concentrações. Em laboratório, a suspensão do pericarpo do fruto apresentou 100% de mortalidade a 100 ppm para desovas de B. glabrata, a 20 ppm para caramujos adultos de Biomphalaria glabrata, B. straminea e B. tenagophila, a 5 ppm para Lebistes reticulatus (peixes e a 1 ppm para cercárias de Schistosoma mansoni. O extrato etanólico do pericarpo do fruto não foi ativo para caramujo adulto de B. glabrata. As doses letais para 90% dos caramujos adultos (DL90, após 24 horas de exposição, usando a suspensão do pericarpo do fruto foram de: 15 ppm para B. glabrata; 14 ppm para B. straminea e 18 ppm para B. tenagophila. As DL90 das suspensões das casca da raiz, sementes e folhas contra B. glabrata foram de 57, 33 e 15 ppm, respectivamente. No campo, coma suspensão do pericarpo do fruto a mortalidade de caramujos adultos de B. glabrata foi de 68% a 20 ppm e 100% a 40 ppmAqueous suspensions of fruit's pericarp, leaves, root's bark and seeds of Guaiacum officinale were tested at different concentrations as molluscicide, cercaricide and piscicide. In the laboratory the suspension of fruit's pericarp produced 100% mortality for egg masses of B. glabrata at 100 ppm, for adult snails of Biomphalaria glabrata, B. straminea and B. tenagophila at 20 ppm, for Lebistes reticulatus (fishes at 5 ppm and Schistosoma mansoni's cercariae at 1 ppm. The ethanolic extract of fruit's pericarp was not active against adult snails of B. glabrata. The letal dose for adult snails(DL90 of the aqueous suspension of fruit's pericarp after 24 hours exposure, were: 15 ppm for B. glabrata; 14 ppm for B. straminea and 18 ppm for B. tenagophila. The DL90 of aqueous suspensions of root's bark, seeds and leaves were 57 ppm, 33 ppm and 15 ppm, respectively. In the field, B. glabrata adult snail

  7. A Multiplex-PCR approach to identification of the Brazilian intermediate hosts of Schistosoma mansoni

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    Vidigal THDA

    2002-01-01

    Full Text Available Due to difficulties concerning morphological identification of planorbid snails of the genus Biomphalaria, and given a high variation of characters and in the organs with muscular tissue, we designed specific polymerase chain reaction (PCR primers for Brazilian snail hosts of Schistosoma mansoni from available sequences of internal transcribed spacer 2 (ITS2 of the ribosomal RNA gene. From the previous sequencing of the ITS2 region, one primer was designed to anchor in the 5.8S conserved region and three other species-specific primers in the 28S region, flanking the ITS2 region. These four primers were simultaneously used in the same reaction (Multiplex-PCR, under high stringency conditions. Amplification of the ITS2 region of Biomphalaria snails produced distinct profiles (between 280 and 350 bp for B. glabrata, B. tenagophila and B. straminea. The present study demonstrates that Multiplex-PCR of ITS2-DNAr showed to be a promising auxiliary tool for the morphological identification of Biomphalaria snails, the intermediate hosts of S. mansoni.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. Critical analysis of molluscicide application in schistosomiasis control programs in Brazil.

    Science.gov (United States)

    Coelho, Pmz; Caldeira, R L

    2016-01-01

    In Brazil, Biomphalaria glabrata, B. tenagophila, and B. straminea are naturally infected by the trematode Schistosoma mansoni, the causative agent of schistosomiasis. Despite decades of governmental efforts through official control programs, schistosomiasis remains an important public health problem in the country: thousands of people are infected with the trematode each year and millions live in endemic areas. The World Health Organization recommends using a combination of molluscicide (niclosamide) and mass chemotherapy to control the transmission of schistosomiasis, with this treatment successfully reducing the morbidity of the disease. In the past, niclosamide has been used in official schistosomiasis control programs in Brazil. However, as B. glabrata recolonizes even after molluscicide application, the use of molluscicides has gradually decreased in the country until they were discontinued in 2002, mainly due to the rising global pressure to preserve the environment and the difficulties of obtaining licenses from the Brazilian Ministry of Environment to use toxic substances in aquatic ecosystems. Therefore, the discovery of new molluscicides, which could be more selective to Biomphalaria species and less harmful to the aquatic ecosystem, is necessary. In addition, political efforts to sensitize funders to provide grants for this field of research are required. In this context, this article aims to make a critical analysis of molluscicide application in schistosomiasis control programs in Brazil. PMID:27374126

  13. 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.

  14. 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.

  15. 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

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

    Directory of Open Access Journals (Sweden)

    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

  17. 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

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. 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.

  1. 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. PMID:15486645

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  5. Paenibacillus, a novel pathogen of Biomphalaria glabrata, an intermediate host for schistosomiasis

    OpenAIRE

    Duval, David; Galinier, Richard; Mouahid, Gabriel; Toulza, Eve; Rognon, Anne; Arancibia, Nathalie; Allienne, Jean-François; Mitta, Guillaume; Théron, André; Gourbal, Benjamin

    2014-01-01

    Schistosomiasis is the second most widespread tropical parasitic disease after malaria. To achieve the objective of schistosomiasis eradication in a decade, various research strategies and treatment programs were recommended and supported by WHO. One of these applicable approaches is based on the control of snail vectors in endemic area. Previous field studies have shown that competitor or predator introduction could be effective but no systemic investigation has ever been conducted to identi...

  6. 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

    ) 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......Despite ongoing preventive chemotherapy campaigns, intestinal schistosomiasis is hyper-endemic in shoreline communities living along Lake Albert, Uganda. To provide a deeper insight into the local epidemiology of Schistosoma mansoni, a variety of field-based studies were undertaken focusing upon...

  7. Differential spatial repositioning of activated genes in Biomphalaria glabrata snails infected with Schistosoma mansoni

    OpenAIRE

    Arican-Goktas, HD; Ittiprasert, W; Bridger, JM; Knight, M.

    2014-01-01

    Schistosomiasis is an infectious disease infecting mammals as the definitive host and fresh water snails as the intermediate host. Understanding the molecular and biochemical relationship between the causative schistosome parasite and its hosts will be key to understanding and ultimately treating and/or eradicating the disease. There is increasing evidence that pathogens that have co-evolved with their hosts can manipulate their hosts' behaviour at various levels to augment an infection. Bact...

  8. Differential spatial repositioning of activated genes in Biomphalaria glabrata snails infected with Schistosoma mansoni.

    OpenAIRE

    Arican-Goktas, Halime D.; Wannaporn Ittiprasert; Joanna M Bridger; Matty Knight

    2014-01-01

    Schistosomiasis is an infectious disease infecting mammals as the definitive host and fresh water snails as the intermediate host. Understanding the molecular and biochemical relationship between the causative schistosome parasite and its hosts will be key to understanding and ultimately treating and/or eradicating the disease. There is increasing evidence that pathogens that have co-evolved with their hosts can manipulate their hosts' behaviour at various levels to augment an infection. Bact...

  9. The nuclear receptors of Biomphalaria glabrata and Lottia gigantea: Implications for developing new model organisms

    OpenAIRE

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

    2015-01-01

    © 2015 Kaur et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited Nuclear receptors (NRs) are transcription regulators involved in an array of diverse physiological functions including key roles in endocrine and metabolic function. The aim of this study was to identify nuclear receptors in the fully seque...

  10. Schistosoma mansoni and Biomphalaria snails in Lake Victoria: distribution, genetics and ecological dynamics

    OpenAIRE

    Standley, Claire J

    2011-01-01

    Intestinal schistosomiasis, caused by the trematode parasite Schistosoma mansoni, is a disease of major public health importance in the Lake Victoria region. Accurate information pertaining to the disease's distribution can greatly assist in the maintenance and realignment of existing control strategies. Rapid mapping of disease prevalence is reliant on diagnostic technologies; in the case of intestinal schistosomiasis, traditional stool-based methods are beginning to be complimented with new...

  11. 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.

  12. Intermediate hosts of schistosoma mansoni in Brazil

    Directory of Open Access Journals (Sweden)

    Omar dos Santos Carvalho

    1992-01-01

    Full Text Available The Brazilian planorbidical chart is slowly but progressively been increased by new data. Distribution of vector species of Schistosoma mansoni, according to Paraense, 1986, may be thus resumed: Biomphalaria glabrata - delimited by paralells 13 and 21-S and meridians 39 and 45-W, area of greater dominance (Southerst Bahia, oriental half of Minas Gerais and Espírito Santo. It is observed along the coast line of the state of Sergipe, Alagoas, Pernambuco, Paraíba and Rio Grande do Norte. Starting from there, it is found towards the southwest, in the direction to the Sao Francisco River and South-Center of Minas Gerais. Isolated population may be observed in other states. Its presence is probably, associated to the transmission of schistosomiasis in all areas where it occurs. B. tenagophila - extends it self through a wide strip of coast-line the South of Bahia (17-45"S, 39-15'W, RS(33-41'S, 53-27'W. In Sao Paulo and Rio Grande do Sul states it is found further inland. It is important in schistosomiasis transmission in the Paraíba valley (SP. Isolated populations are observed in the Federal District and Minas Gerais state. B. straminea - better adapter species to climatic variation, having a more dense ditribution in the northeast (41-Wand 110-S, south of Bahia and northeast of Minas Gerais (150 and 180-S, 400 and 440-W It is less susceptible than B. glabrata, being however the most important responsible for the transmission of S. mansoni in the northeast, chiefly in the northeastern dry area, where it is almost the only transmissive species.

  13. 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.

  14. 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.

  15. 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

  16. [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.

  17. Factors associated with schistosomiasis mansoni in a population from the municipality of Jaboticatubas, State of Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Cristiano Lara Massara

    2004-08-01

    area identified snails of the species Biomphalaria straminea and B. glabrata. The latter showed 17 (0.6% specimens positive for S. mansoni. Qualitative studies have complemented such evidences, which allowed us to design a reference picture and specific indicators of the disease for the local population. Those data provided the essential information to continue the development of an already ongoing educative process, as well as projects on environmental improvements.

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

    OpenAIRE

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

  19. 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, ...

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

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    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%.

  1. 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

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    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.

  2. 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)

    OpenAIRE

    Nelymar Martineli Mendes; Naftale Katz

    1983-01-01

    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 [(MgCO3)4.Mg(OH)2.nH2O], nitrato de magnésio [Mg(NO3)2. 6H2O...

  3. 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...

  4. 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.

  5. Pseudomonas seleniipraecipitatus sp. nov.: A selenite reducing -proteobacteria isolated from soil

    Science.gov (United States)

    Abstract: A Gram-negative, yellow pigmented bacterium designated strain CA5 that reduced selenite to elemental red selenium (Se0) was isolated from soil. 16S rRNA gene sequence alignment identified the isolate as a novel Pseudomonas sp. with P. argentinensis, P. flavescens and P. straminea as its c...

  6. The unfoldomics decade: an update on intrinsically disordered proteins

    OpenAIRE

    Vacic Vladimir; Chen Jessica; Yang Jack Y; Romero Pedro; Meng Jingwei; Oldfield Christopher J; Dunker A Keith; Obradovic Zoran; Uversky Vladimir N

    2008-01-01

    Abstract Background Our first predictor of protein disorder was published just over a decade ago in the Proceedings of the IEEE International Conference on Neural Networks (Romero P, Obradovic Z, Kissinger C, Villafranca JE, Dunker AK (1997) Identifying disordered regions in proteins from amino acid sequence. Proceedings of the IEEE International Conference on Neural Networks, 1: 90–95). By now more than twenty other laboratory groups have joined the efforts to improve the prediction of prote...

  7. 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.

  8. 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.

  9. Latex of "Coroa de Cristo" (Euphorbia Splendens: an effective molluscicide

    Directory of Open Access Journals (Sweden)

    Maurício C. de Vasconcelos

    1986-12-01

    Full Text Available An aqueous solution of the latex of "coroa de cristo" (Euphorbia splendens var. hislopii showed molluscicide action (LD90 at a concentration lower than 0.5 ppm on Biomphalaria glabrata and B. tenagophila reared in laboratory and at a concentration lower than 4.0 ppm for field B. tenagophila.Foi estudada em laboratório a atividade moluscicida do látex da "coroa de cristo" (Euphorbia splendens var. hislopii. A planta apresentou ação moluscicida (DL90 a uma concentração inferior de 0,5ppm para Biomphalaria glabrata e Biomphalaria tenagophila de laboratório e inferior a 4ppm para caramuhos de campo.

  10. 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.

  11. 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)

  12. 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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  14. Dicty_cDB: Contig-U03225-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 3163 ) Biomphalaria glabrata chromosome UNK clone BG_BBa... 50 0.054 6 ( CO733545 ) SlLT02c06a08f1 squirrel ... 0.079 18 ( CO738531 ) SlLE04c20l23f1 squirrel embryo library 1 Spermoph... 40 0.

  15. Molluscicidal saponins from Phytolacca dodecandra

    DEFF Research Database (Denmark)

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

    1993-01-01

    -beta-D-xylopyranosyl-(1-->6)-O-beta-D-gluco-pyranosyl-(1-->3)]-beta -D-glucopyranosyloleanolic acid mainly by spectroscopic methods (LSIMS, H-1 NMR, COSY, NOESY, TOCSY, J-resolved H-1 NMR, C-13 NMR, HETCOR). The saponins are potent molluscicides against the schistosomiasis transmitting snail Biomphalaria glabrata with LC...

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

    Directory of Open Access Journals (Sweden)

    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. 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....... In contrast, the coumarin anticoagulant warfarin (3) did not show molluscicidal activity....

  18. Formas de apresentação do sofrimento psíquico: alguns tipos clínicos no Brasil contemporâneo

    Directory of Open Access Journals (Sweden)

    Christian Dunker Ingo Lenz

    2004-01-01

    Full Text Available The present article argues the patterns of the psychic suffering in the picture of the tending discourses of homogenization of the subjectivity. One understands for clinical type regular forms of presentation of the psychic suffering that endorse in its expression, different discoursive strategies. The patterns operates generating particular forms of subjectivity where its tension with the universal that determines it does not appear dialetically. The singularity is abstained in this process as constituent aspect of the subject. The discourse is taken in the meaning formulated by Lacan (1968. We take the notion of neurotic jouissance calculus (Dunker, 2003 to indicate the operations of discourse encripting of the organization of the suffering by the subject. The objective of the study is to describe as such clinical types finish for composing different relations between the subject, knowing and the jouissance. Configurations these that are congruent with certain ideological formations contemporaries, particularly the estetization of the subjectivity.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Karyotypes of three species of the marine Veneroida molluscs

    Institute of Scientific and Technical Information of China (English)

    Sun Zhenxing; Shao Yanqun; Guo Shengchao; Qin Yan; Yang Aiguo

    2003-01-01

    The karyotypes of three species of marine Veneroida molluscs, Solen grandis Dunker,Saxidomus purpuratus Sowerby and Mactra chinensis Philippi were studied by using the adult gill tissues. The chromosomes were prepared through injecting phytohemagglutinin (PHA) and colchicine, hypotonic treatment, chopping air-dry, and squashing technology. The results show that the diploid chromosome numbers of the three Veneroida species are the same as 2 n = 38. The karyotype of Solen grandis is 26m + 6sm + 2st + 4t, NF = 70, the karyotype of Saxidomus purpuratus is 32m + 2sm + 4st/t, NF = 72, and the karyotype of Mactra chinensis is 20m + 16sm + 2st/t, NF = 74. Satellite and sex chromosome were not found among the chromosomes of three species.

  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)

    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.

  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)

    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.

  3. Population dynamics of aquatic snails in Pampulha reservoir

    Directory of Open Access Journals (Sweden)

    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.

  4. Screening of Malian medicinal plants for antifungal, larvicidal, molluscicidal, antioxidant and radical scavenging activities.

    Science.gov (United States)

    Diallo, D; Marston, A; Terreaux, C; Touré, Y; Paulsen, B S; Hostettmann, K

    2001-08-01

    A total of 78 different extracts from 20 medicinal plants belonging to 14 plant families from Mali were tested for their antifungal, larvicidal, molluscicidal, antioxidant and radical scavenging activities. Dichloromethane, methanol, water and ethanol extracts were used. TLC autobiography for antifungal activity was run with Cladosporium cucumerinum and Candida albicans. Extracts were also tested on the larvae of the mosquitoes Aedes aegypti, Anopheles gambiae and Culex quinquefasciatus. Molluscicidal activities were established with the snails Biomphalaria glabrata, Biomphalaria pfeifferi and Bulinus truncatus. beta-Carotene and DPPH solutions sprayed on TLC plates were used for antioxidant and radical scavenging assays. Of the extracts investigated, 20% were antioxidant and radical scavengers, 19% fungicidal, 30% were larvicidal and 11% were molluscicidal. Three of the plant extracts, from Cussonia barteri (Araliaceae), Glinus oppositifolius (Aïzoaceae) and Lannea velutina (Anacardiaceae) gave positive responses in all four tests. PMID:11507731

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

    Directory of Open Access Journals (Sweden)

    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.

  6. 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. PMID:22291716

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

    Science.gov (United States)

    Fu, Peng-Cheng; Zhang, Yan-Zhao; Geng, Hui-Min

    2016-01-01

    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 taxa cp genomes

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

    OpenAIRE

    Nelymar Martineli Mendes; Darcilio Fernandes Baptista; Maurício Carvalho Vasconcellos; Virgínia Torres Schall

    1992-01-01

    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.

  9. 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

    OpenAIRE

    Pedro Coura Filho; Roberto Sena Rocha; Maria Fernanda Furtado de Lima e Costa; Naftale Katz

    1992-01-01

    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 C...

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

    OpenAIRE

    Clisiane C.S. Santos; Silvan S. Araújo; André L. L. M. Santos; Elis C.V. Almeida; Antônio S. Dias; Nicole P. Damascena; Deisylaine M. Santos; Matheus I.S. Santos; Karlos A.L.R. Júnior; Carla K. B. Pereira; Amanda C.B. Lima; Andrea Y.K.V. Shan; Antônio E. G. Sant'Ana; Charles S. Estevam; Brancilene S. de Araujo

    2014-01-01

    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 performe...

  11. The prolonged use of niclosamide as a molluscicide for the control of Schistosoma mansoni Uso prolongado da niclosamida como moluscicida para o controle do Schistosoma mansoni

    OpenAIRE

    Pedro Coura-Filho; Nelymar Martinelli Mendes; Cecilia Pereira de Souza; José Pedro Pereira

    1992-01-01

    Applications of niclosamide at three-monthly intervals were undertaken for 14 years in foci of Biomphalaria glabrata in the water sources of Peri-Peri (Capim Branco, MG). All the residents of the area were submitted to an annual fecal examination (Kato/Katz) and those individuals eliminating Schistosoma mansoni eggs were treated with oxamniquine. A malacological survey was undertaken at three-monthly intervals by means of ten scoops with a perforated ladle each ten metres along the two banks ...

  12. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  14. Schistosomiasis in Southern Brazil 17 years after the confirmation of the first autochthonous case

    OpenAIRE

    Demetrius da Silva Martins; Mariana Fabris Xavier; Franciéle de Souza Masiero; Juliana Cordeiro; Patrícia Jacqueline Thyssen

    2015-01-01

    INTRODUCTION: Schistosomiasis, a parasitic disease, is an important public health issue in Brazil, particularly Northern Brazil. Since the first recorded occurrence of Biomphalaria glabrata in the States of Santa Catarina and Rio Grande do Sul, it has spread to South Brazil. METHODS: Using the Information System for Notifiable Diseases (SINAN), we assessed the disease spread in Southern Brazil. RESULTS: In Rio Grande do Sul, nine localities had confirmed cases (n = 95, 2001-2013). CONCLUSIONS...

  15. Saponins from Swartzia langsdorffii: biological activities

    OpenAIRE

    2003-01-01

    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...

  16. The Holozoan Capsaspora owczarzaki Possesses a Diverse Complement of Active Transposable Element Families

    OpenAIRE

    Carr, Martin; Suga, Hiroshi

    2014-01-01

    Capsaspora owczarzaki, a protistan symbiont of the pulmonate snail Biomphalaria glabrata, is the centre of much interest in evolutionary biology due to its close relationship to Metazoa. The whole genome sequence of this protist has revealed new insights into the ancestral genome composition of Metazoa, in particular with regard to gene families involved in the evolution of multicellularity. The draft genome revealed the presence of 23 families of transposable element, made up from DNA transp...

  17. Bioassay guided isolation of a new C18-polyacetylene, (+)-9(Z),17-octadecadiene-12,14-diyne-1,11,16-triol, from Cassonia barteri.

    Science.gov (United States)

    Papajewski, S; Guse, J H; Klaiber, I; Roos, G; Süssmuth, R; Vogler, B; Walter, C U; Kraus, W

    1998-06-01

    A novel C18-polyacetylene, (+)-9( Z),17-octadecadiene-12,14-diyne-1,11,16-triol, has been isolated from the ethyl acetate extract of Cassonia barteri (Araliaceae) leaves collected in Cameroon. The structure determination was achieved by NMR, mass, IR, and UV spectroscopy. The new polyenyne shows antibacterial activity against Bacillus subtilis and Pseudomonas fluorescens, antifungal activity against Cladosporium cucumerinum, moiluscicidal activity against Biomphalaria glabrata at low concentrations, and in addition it possesses haemolytic activity. PMID:17253268

  18. 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)

  19. A family of fibrinogen-related proteins that precipitates parasite-derived molecules is produced by an invertebrate after infection

    OpenAIRE

    Adema, Coen M.; Lynn A Hertel; Miller, Robert D.; Eric S Loker

    1997-01-01

    After infection with the digenetic trematode Echinostoma paraensei, hemolymph of the snail Biomphalaria glabrata contains lectins comprised of 65-kDa subunits that precipitate polypeptides secreted by E. paraensei intramolluscan larvae. Comparable activity is lacking in hemolymph of uninfected snails. Three different cDNAs with sequence similarities to peptides derived from the 65-kDa lectins were obtained and unexpectedly found to encode fibrinogen-related proteins (FREPs). These FREPs also ...

  20. 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

    OpenAIRE

    Oswaldo Marçal Júnior; Luiz Koodi Hotta; Rosa Maria de Jesus Patucci; Carmen Moreno Glasser; Luiz Candido de Souza Dias

    1993-01-01

    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 ...

  1. 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%).

  2. Glycotope Sharing between Snail Hemolymph and Larval Schistosomes: Larval Transformation Products Alter Shared Glycan Patterns of Plasma Proteins

    OpenAIRE

    YOSHINO, TIMOTHY P.; Wu, Xiao-Jun; Liu, Hongdi; Gonzalez, Laura A.; Deelder, André M; Cornelis H Hokke

    2012-01-01

    Recent evidence supports the involvement of inducible, highly diverse lectin-like recognition molecules in snail hemocyte-mediated responses to larval Schistosoma mansoni. Because host lectins likely are involved in initial parasite recognition, we sought to identify specific carbohydrate structures (glycans) shared between larval S. mansoni and its host Biomphalaria glabrata to address possible mechanisms of immune avoidance through mimicry of elements associated with the host immunoreactivi...

  3. [Malacologic-schistosomal study of the refugee camps on the Plain of Ruzizi in the Democratic Republic of the Congo].

    Science.gov (United States)

    Baluku, B; Bagalwa, M; Basabose, K

    1999-01-01

    Bilharziasis due to Schistosoma mansoni is widespread in the eastern part of the People's Republic of the Congo, particularly in the Ruzizi plain area. The intermediate host is the fresh-water snail Biomphalaria pfeifferi whose ecology is now well documented. Bilharziasis due to Schistosoma haematobium and Schistosoma intercalatum have not yet been observed but the potential for this development is high given the presence of the intermediate hosts, i.e. Bulinus truncatus, Bulinus globosus, and Bulinus forskalii, and the migration of populations in the area. Malacological and cercariometric studies were undertaken in 3 refugee camps in 1995. Findings showed that Biomphalaria pfeifferi was present in all water systems tested but that levels varied from 21 p. 100 to 70 p. 100 from one camp to another. The rate of infestation by Biomphalaria pfeifferi varied from 37 to 20 p. 100 depending on the sampling site. Given the prevalence of Schistosoma mansoni in the population, extension of bilharziasis is likely in the Ruzizi plain area and its surroundings. Potential intermediary hosts for Schistosoma haematobium and Schistosoma intercalatum were of lower relative prevalence and were found in specific biotopes. The authors propose methods of controlling water snails and preventing infection of people and water systems. PMID:10472580

  4. Supplementary descriptive notes of the Sinella and Coecobrya (Collembola: Entomobryidae) species from North America, Hawaii and Japan.

    Science.gov (United States)

    Wu, Jun; Yan, Qibao; Zhang, Feng

    2016-01-01

    Many known collembolan species lack sufficient descriptive details so that further taxonomical comparison cannot be achieved. When sorting documents and materials from Prof. Jian-Xiu CHEN, Nanjing University, we found many old but valuable drafts on Sinella and Coecobrya species from North America, Hawaii and Japan. Supplementary descriptions, particularly chaetotaxy, were provided for the following species: S. agna Christiansen & Bellinger, 1980, S. alata Christiansen, 1960, S. baca Christiansen & Bellinger, 1980, S. barri Christiansen, 1960, S. hoffmani Wray, 1952, S. sexoculata (Schött, 1896), S. straminea (Folsom, 1899), S. yosiia Christiansen & Bellinger, 1992, C. akiyoshiana Yosii, 1956, C. borerae Christiansen & Bellinger, 1992, C. ishikawai Yosii, 1956, C. kukae Christiansen & Bellinger, 1992, C. lua Christiansen & Bellinger, 1992, C. nupa Christiansen & Bellinger, 1992, C. tibiotarsalis Yosii, 1964. Sinella cavernarum (Packard, 1888) was redescribed based on topotypes and more additional materials. PMID:27394318

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

    Directory of Open Access Journals (Sweden)

    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

  6. Esquistossomose mansoni em duas mesorregiões do Estado de Alagoas Schistosomiasis mansoni in two mesoregions of the State of Alagoas

    Directory of Open Access Journals (Sweden)

    Janira Lúcia Assumpção Couto

    2005-08-01

    Full Text Available No Brasil, índices elevados da esquistossomose mansônica correspondem, na grande maioria dos casos, à presença da espécie Biomphalaria glabrata, principal transmissora do Schistosoma mansoni, nas localidades endêmicas. Foi realizado estudo em 40 municípios endêmicos do Estado de Alagoas, com o objetivo de verificar a existência da espécie e sua importância na manutenção da esquistossomose nesse Estado. Desses municípios, 28 são pertencentes à mesorregião do leste Alagoano e 12 à mesorregião do Agreste Alagoano. Os moluscos procederam de diversos tipos de criadouros: riachos, córregos, valas, açudes, brejos e poços. As coletas foram realizadas no período de fevereiro de 1996 a dezembro de 1998. Para a identificação de Biomphalaria glabrata, foi efetuado o exame anatômico das partes moles, após remoção das conchas. A detecção de cercárias do Schistosoma mansoni foi realizada através da técnica de esmagamento, calculando-se o percentual de infecção. Em 32 (80% dos municípios estudados foi encontrada Biomphalaria glabrata, seis deles apresentando moluscos infectados com cercárias do parasita. Penedo apresentou a maior (6,6% taxa de infecção, seguindo-se Ibateguara (5,6%. Taxas menores foram observadas em Chã Preta (2,7%, em Murici (2,5%, Porto Real do Colégio (0,1% e Igreja Nova (0,1%. O inquérito copro-parasitológico efetuado pela Fundação Nacional de Saúde em 1997, 1998/1999 e 2000, confirmou a importância da endemia nessas regiões do Estado.In Brazil, high levels of schistosomiasis mansoni are linked to the presence of the species Biomphalaria glabrata, considered to be the main host of Schistosoma mansoni in endemic areas. This work conducted a survey of 40 endemic municipalities in the State of Alagoas, aiming at identifying this species and its important role in the maintenance of schistosomiasis. Among the municipalities surveyed, 28 lie in the mesoregion of the Leste Alagoano and 12, in the

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

    Science.gov (United States)

    Balabanova, Larissa; Nedashkovskaya, Olga; Podvolotskaya, Anna; Slepchenko, Lubov; Golotin, Vasily; Belik, Alexey; Shevchenko, Ludmila; Son, Oksana; Rasskazov, Valery

    2016-09-01

    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. PMID:27508225

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Cognitive maps across cultures and across sciences.

    Directory of Open Access Journals (Sweden)

    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.

  10. 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.

  11. Space-time variation of the relative abundance of Limnoperna fortunei in deep zones of São Gonçalo Channel, Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Michelle Lopes

    2012-12-01

    Full Text Available This work describes the spatial-temporal variation of the relative abundance and size of Limnoperna fortunei (Dunker, 1857 collected in São Gonçalo Channel through bottom trawl with a 0.5 cm mesh, at depths between 3 and 6 m. The estimative of mean relative abundance (CPUE ranged from 2,425.3 individuals per drag (ind./drag in the spring to 21,715.0 ind./drag in the fall, with an average of 9,515.3 ind./drag throughout the year. The estimated mean density of L. fortunei for the deep region of São Gonçalo Channel ranged from 1.2 to 10.3 ind./m², and it was recorded a maximum density of 84.9 ind./m² in the fall of 2008. The method of sampling using bottom trawl enabled the capture of L. fortunei under the soft muddy bottom of the channel, in different sizes ranging from 0.4 to 3.2 cm. This shows that the structure of the L. fortunei adult population under the bottom of the São Gonçalo Channel is composed mostly of small individuals (<1.4 cm, which represent up to 74% of the population collected.

  12. 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.

  13. Intermediate hosts of schistosoma mansoni in Brazil

    OpenAIRE

    Omar dos Santos Carvalho

    1992-01-01

    The Brazilian planorbidical chart is slowly but progressively been increased by new data. Distribution of vector species of Schistosoma mansoni, according to Paraense, 1986, may be thus resumed: Biomphalaria glabrata - delimited by paralells 13 and 21-S and meridians 39 and 45-W, area of greater dominance (Southerst Bahia, oriental half of Minas Gerais and Espírito Santo). It is observed along the coast line of the state of Sergipe, Alagoas, Pernambuco, Paraíba and Rio Grande do Norte. Starti...

  14. 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

    OpenAIRE

    Alejandro Cruz-Reys; Carolina Chavarin; Martha P. Campos Arias; Javier Taboada; Manuel Jímenez E.

    1989-01-01

    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 utiliza...

  15. Latex of "Coroa de Cristo" (Euphorbia Splendens): an effective molluscicide

    OpenAIRE

    Maurício C. de Vasconcelos; Virgínia T. Schall

    1986-01-01

    An aqueous solution of the latex of "coroa de cristo" (Euphorbia splendens var. hislopii) showed molluscicide action (LD90) at a concentration lower than 0.5 ppm on Biomphalaria glabrata and B. tenagophila reared in laboratory and at a concentration lower than 4.0 ppm for field B. tenagophila.Foi estudada em laboratório a atividade moluscicida do látex da "coroa de cristo" (Euphorbia splendens var. hislopii). A planta apresentou ação moluscicida (DL90) a uma concentração inferior de 0,5ppm pa...

  16. 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

    OpenAIRE

    Nelymar Martineli Mendes; José Pedro Pereira; Cecília Pereira de Souza; Maria de Lourdes Lima de Oliveira

    1984-01-01

    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 pulch...

  17. Schistosomiasis in Southern Brazil 17 years after the confirmation of the first autochthonous case

    Directory of Open Access Journals (Sweden)

    Demetrius da Silva Martins

    2015-06-01

    Full Text Available INTRODUCTION: Schistosomiasis, a parasitic disease, is an important public health issue in Brazil, particularly Northern Brazil. Since the first recorded occurrence of Biomphalaria glabrata in the States of Santa Catarina and Rio Grande do Sul, it has spread to South Brazil. METHODS: Using the Information System for Notifiable Diseases (SINAN, we assessed the disease spread in Southern Brazil. RESULTS: In Rio Grande do Sul, nine localities had confirmed cases (n = 95, 2001-2013. CONCLUSIONS: We confirmed disease expansion to Southern Brazil. We demonstrated the effectiveness of SINAN to monitor notifiable diseases. Our results are useful to develop preventive actions for schistosomiasis control.

  18. The molluscicidal properties of Apodytes dimidiata subsp. dimidiata (Icacinaceae).

    Science.gov (United States)

    Pretorius, S J; Joubert, P H; Scott, A H; Fourie, T G

    1991-06-01

    The molluscicidal and piscicidal activity of extracts from the leaves, berries and bark of the tree Apodytes dimidiata were evaluated experimentally. The leaves were highly toxic to both Bulinus africanus and Biomphalaria pfeifferi, the intermediate host snails of Schistosoma spp. B. pfeifferi profusely exuded mucus which appeared to render some protection against the toxic substance(s) of the plant but did not prevent their eventual demise. The LC10 after one-hour exposures of fish (Oreochromis mossambicus) was within molluscicidal levels. PMID:2051521

  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. 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...

  1. Biological screening of Brazilian medicinal plants

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    Alves Tânia Maria de Almeida

    2000-01-01

    Full Text Available In this study, we screened sixty medicinal plant species from the Brazilian savanna ("cerrado" that could contain useful compounds for the control of tropical diseases. The plant selection was based on existing ethnobotanic information and interviews with local healers. Plant extracts were screened for: (a molluscicidal activity against Biomphalaria glabrata, (b toxicity to brine shrimp (Artemia salina L., (c antifungal activity in the bioautographic assay with Cladosporium sphaerospermum and (d antibacterial activity in the agar diffusion assay against Staphylococcus aureus, Escherichia coli, Bacillus cereus and Pseudomonas aeruginosa. Forty-two species afforded extracts that showed some degree of activity in one or more of these bioassays.

  2. 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

  3. 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

    Directory of Open Access Journals (Sweden)

    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.

  4. 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.

  5. 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

    Directory of Open Access Journals (Sweden)

    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.

  6. Simian malaria at two sites in the Brazilian Amazon: I-The infection rates of Plasmodium brasilianum in non-human primates

    Directory of Open Access Journals (Sweden)

    Ricardo Lourenço-de-Oliveira

    1995-06-01

    Full Text Available The parasite that causes simian malaria in the Brazilian Amazon, Plasmodium brasilianum, is infective to man. In this region, where humans live within and in close proximity to the forest, it was suspected that this parasite could be the cause of a zoonosis. A study was performed in the areas surrounding two hydroelectric plants in the Amazon, Balbina and Samuel, aiming at determining the zoonotic potential of this parasite. P. brasilianum was detected in, respectively, 15.8% and 9.9% of 126 and 252 primates belonging to seven and eight species examined from Balbina and Samuel. The highest malaria infection rates were found among the red-howler monkey Alouatta seniculus straminea (32.3%, the bearded-saki Chiropotes satanas chiropotes (50% and the spider-monkey Ateles paniscus paniscus (2[1+] from Balbina and in the squirrel-monkey Saimiri ustus (21% and the black-faced-spider-monkey Ateles paniscus chamek (28.6% from Samuel.

  7. 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.

  8. 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.

  9. Simian malaria at two sites in the Brazilian Amazon. I--The infection rates of Plasmodium brasilianum in non-human primates.

    Science.gov (United States)

    Lourenço-de-Oliveira, R; Deane, L M

    1995-01-01

    The parasite that causes simian malaria in the Brazilian Amazon, Plasmodium brasilianum, is infective to man. In this region, where humans live within and in close proximity to the forest, it was suspected that this parasite could be the cause of a zoonosis. A study was performed in the areas surrounding two hydroelectric plants in the Amazon, Balbina and Samuel, aiming at determining the zoonotic potential of this parasite. P. brasilianum was detected in, respectively, 15.8% and 9.9% of 126 and 252 primates belonging to seven and eight species examined from Balbina and Samuel. The highest malaria infection rates were found among the red-howler monkey Alouatta seniculus straminea (32.3%), the bearded-saki Chiropotes satanas chiropotes (50%) and the spider-monkey Ateles paniscus paniscus (2[1+]) from Balbina and in the squirrel-monkey Saimiri ustus (21%) and the black-faced-spider-monkey Ateles paniscus chamek (28.6%) from Samuel. PMID:8544737

  10. A bio-stratigraphy evidence of summer monsoon drift on a large scale toward NW China during the Holocene Megathermal%全新世大暖期时中国夏季风向西北大幅度漂移的一个古生物地层学证据

    Institute of Scientific and Technical Information of China (English)

    李保生; 王丰年; 杜恕环; HOFMANN Jürgen; 陈德牛; 温小浩; 闫满存; ZHANG David Dian; 牛东风; 李志文; 邱世藩

    2010-01-01

    The lacustrine sediment contains a great amount of gasteropod fossils of the Holocene Megathermal (6~9 ka BP) of the Badanhaizi Lower Land located at southeastern margin of Badainjaran Desert, China. These areRadix cucunorica (Möellendorff),Succinea erythrophanaAncey,Gyraulus sibricus (Dunker),Radix lagotis (Schranck),Gyraulus albus(Müller),Lymnaea stagnalis(Linnaeus),Gyraulus convexiusculus (Hutton), in which, except terraneousSuccinea erythrophanaAncey, the rest belongs to freshwater gasteropods. They indicate then warm-humid climate, among which the existent northwesternmost of the extantGyraulus convexiusculus (Hutton) is of Nanniwan of Shanxi Province of Chinese warm temperate belt. Hence, it is assumed that during 6~9 ka B. P. the annual average temperature and precipitation of Badanhaizi probably were respectively 1.1℃ and 440 mm higher than those of the present-day; from Nanniwan to Badanhaizi, the climate belt almost migrated northwestward 700 km; the warm front of summer monsoon may moved to northwestward the range from Yumen to Ejin Qi in NE strike and further to the Sino-Mongolia boundary at that time, and its inlfuencing extension probably attained to Xingxingxia, the inner continent, of the boundary between Gansu and Xinjiang, China.%巴丹吉林沙漠东南部边缘巴丹海子全新世大暖期6~9 ka BP的湖相沉积中含有大量腹足类化石——Radix cucunorica(Möellendorff),Succinea erythrophanaAncey,Gyraulus sibricus (Dunker),Radix lagotis (Schranck),Gyraulus albus(Müller),Lymnaea stagnalis(Linnaeus), Gyraulus convexiusculus (Hutton),除Succinea erythrophanaAncey属陆生蜗牛外,余皆为淡水腹足类。这些化石代表了当时温暖湿润的气候环境。其中,现生的Gyraulus convexiusculus (Hutton)生活的最NW位置为地处暖温带的南泥湾,据此推知,6~9 ka BP时的巴丹海子的气温和降水至少较今分别高出1.1℃和440 mm;从南泥湾至巴丹海子,

  11. Space-time variation of the relative abundance of Limnoperna fortunei in deep zones of São Gonçalo Channel, Rio Grande do Sul, Brazil Variação espaço-temporal da abundância relativa de Limnoperna fortunei em zonas profundas do canal São Gonçalo, Rio Grande do Sul, Brasil

    Directory of Open Access Journals (Sweden)

    Michelle Lopes

    2012-01-01

    Full Text Available This work describes the spatial-temporal variation of the relative abundance and size of Limnoperna fortunei (Dunker, 1857 collected in São Gonçalo Channel through bottom trawl with a 0.5 cm mesh, at depths between 3 and 6 m. The estimative of mean relative abundance (CPUE ranged from 2,425.3 individuals per drag (ind./drag in the spring to 21,715.0 ind./drag in the fall, with an average of 9,515.3 ind./drag throughout the year. The estimated mean density of L. fortunei for the deep region of São Gonçalo Channel ranged from 1.2 to 10.3 ind./m², and it was recorded a maximum density of 84.9 ind./m² in the fall of 2008. The method of sampling using bottom trawl enabled the capture of L. fortunei under the soft muddy bottom of the channel, in different sizes ranging from 0.4 to 3.2 cm. This shows that the structure of the L. fortunei adult population under the bottom of the São Gonçalo Channel is composed mostly of small individuals (Este trabalho descreve a variação espaço-temporal da abundância relativa e tamanho de Limnoperna fortunei (Dunker, 1857 coletados no Canal São Gonçalo através de rede de arrasto de fundo com malha 0,5 cm, em profundidades entre 3 e 6 m. As estimativas de abundância relativa média (CPUE variaram de 2.425,3 ind./arrasto, na primavera a 21.715,0 ind./arrasto no outono, com média de 9.515,3 ind./ arrasto ao longo do ano. A densidade média estimada para L. fortunei para a região profunda do Canal São Gonçalo variou de 1,2 a 10,3 ind./m², sendo registrada uma densidade máxima de 84,9 ind./m² no outono de 2008. O método de coleta com arrasto de fundo possibilitou a captura de L. fortunei sob o fundo mole lodoso do canal, em tamanhos variando de 0,4 a 3,2 cm, revelando que a estrutura da população adulta de L. fortunei sob fundo do Canal São Gonçalo é composta, em sua maioria, por indivíduos pequenos (<1,4 cm, os quais representam até 74% da população coletada.

  12. 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

  13. 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. PMID:17402106

  14. 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.

  15. [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.

  16. [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.

  17. 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

    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...... irrigation canals or lakes in these schemes play an important role in the transmission of human schistosomes and transmission appears to be very focal in these habitats. Infected snails are almost exclusively found in well-defined human water contact sites (WCS). Local infection rates with schistosomes were......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...

  18. Forma pseudoneoplásica de esquistossomose pulmonar crônica sem hipertensão pulmonar Pseudotumoral presentation of chronic pulmonary schistosomiasis without pulmonary hypertension

    OpenAIRE

    Gisane Cavalcanti Rodrigues; Domício Carvalho Lacerda; Edson da Silva Gusmão; Fernando Antônio Colares; Vinícius Turano Mota

    2009-01-01

    A esquistossomose é uma doença que, no Brasil, é causada pelo Schistosoma mansoni e transmitida através da água por moluscos do gênero Biomphalaria. Essa espécie ocorre na África, nas Antilhas e na América do Sul. O parasita, ao atingir a fase adulta de seu ciclo biológico no sistema vascular do homem, alcança as veias mesentéricas. Cada fêmea põe cerca de 400 ovos por dia, e estes, a partir da submucosa, chegam à luz intestinal. Há relatos de casos a respeito de ovos de S. mansoni nos pulmõe...

  19. 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.

  20. Dicty_cDB: VHK492 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available to SW:EF2_CAEEL P29691 ELONGATION FACTOR 2 ;, mRNA sequence. 72 2e-09 1 BI502325 |BI502325.1 kt88b08.y1 Strong...ar to SW:EF2_CAEEL P29691 ELONGATION FACTOR 2 ;, mRNA sequence. 72 2e-09 1 BI324290 |BI324290.1 kt56e07.y1 Strong...yloides ratti L1 pAMP1 v3 Chiapelli McCarter Strongyloides ratti cDNA 5' similar to SW:EF2_CAEEL P29691 ELONG...its) Value N M26017 |M26017.1 D.discoideum elongation factor 2 mRNA, complete cds. 220 4e-54 1 CK149257 |CK1...49257.1 3017HFEX11E1 BgORESTES schistosome-exposed NHM 3017 Head/foot Biomphalaria glabrata cDNA clone ZB9166 similar to Elong

  1. 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

  2. Gastropod diversity, distribution and abundance in habitats with and without anthropogenic disturbances in Lake Victoria, Kenya

    DEFF Research Database (Denmark)

    Lange, C. N.; Kristensen, Thomas K.; Madsen, Henry

    2013-01-01

    We investigated freshwater gastropod diversity, abundance and distribution in habitats with and without anthropogenic disturbance in two localities, Ndere in the Winam Gulf and Mbita Point, Lake Victoria, Kenya, from May 2002 to January 2004. A total of 133 984 gastropod specimens belonging to 15...... species were recorded, 14 from Mbita and 12 from Ndere. Two species, Ferrissia kavirondica and Cleopatra cridlandi, which were recorded only from undisturbed habitats, could be indicators of least disturbed habitats. Water chemistry did differ between fish landing sites and undisturbed habitats at some...... sampling times, indicating that differences due to human impact do exist, but these are dependent on periods of calm weather. The study shows that anthropogenic disturbances cause ecological changes that can be exploited by some snail species, especially Biomphalaria choanomphala and Melanoides tuberculata...

  3. 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.

  4. An aquatic ecosystem in space.

    Science.gov (United States)

    Voeste, D; Andriske, M; Paris, F; Levine, H G; Blum, V

    1999-07-01

    The Closed Equilibrated Biological Aquatic System (CEBAS) Mini-Module experiment was designed to study aquatic ecosystem performance within a middeck locker on the Space Shuttle. CEBAS was flown aboard STS-89 in January 1998 with a population of four pregnant Xiphophorus helleri female fish and eleven adult Biomphalaria glabrata snails in the first compartment and 200 juvenile X. helleri and 48 adult and juvenile B. glabrata in the second compartment. A plant compartment contained eleven snails and 53 g of the aquatic angiosperm Ceratophyllum demersum. During the flight, Ceratophyllum fresh weight increased from 53 g to 117 g. All adult fish and 65 juveniles survived the flight experiment and 37 adult snails and 40 newly laid snail spawn packs were recovered after the flight. Oxygen production and pH were as expected.

  5. A study of the larvicidal and molluscicidal activities of some medicinal plants from northeast Brazil.

    Science.gov (United States)

    de S Luna, J; dos Santos, A F; de Lima, M R F; de Omena, M C; de Mendonça, F A C; Bieber, L W; Sant'Ana, A E G

    2005-02-28

    In a search for natural products that could be used to control the vectors of tropical diseases, 23 extracts of medicinal plants from the northeast of Brazil have been tested for molluscicidal activity against egg masses and adults of the snail Biomphalaria glabrata, for larvicidal activity against the larvae of the mosquito Aedes aegypti, and for general toxicity against the larvae of the brine shrimp Artemia salina. Of these extracts, two were active against the adult snail, one against snail egg masses, eight against the larvae of the mosquito, and 16 showed toxicity towards the brine shrimp. Chemical tests indicated that a wide variety of natural product classes were present in those extracts that showed significant activities in the bioassays. PMID:15707752

  6. Search for antifungal, molluscicidal and larvicidal compounds from African medicinal plants.

    Science.gov (United States)

    Marston, A; Maillard, M; Hostettmann, K

    1993-03-01

    African medicinal plants provide a rich source of biologically-active natural products. By the use of simple bioassays in conjunction with an approach involving bioactivity guided fractionation, it is possible to isolate novel compounds with interesting properties. Several hundred plant extracts have been submitted to different screens, including bioautography on TLC plates with the fungi Cladosporium cucumerinum and Candida albicans. Among the other test systems are a bioassay for molluscicidal activity with the schistosomiasis-transmitting snail Biomphalaria glabrata and a benchtop assay for larvicidal activity with larvae of the mosquito Aedes aegypti, the vector of yellow fever. Using a variety of modern separation techniques, a number of compounds with activity in these bioassays have been isolated. These include prenylated xanthones, tetracyclic phenols and saponins. The role of saponins and saponin-containing plants in the control of schistosomiasis is outlined. PMID:8510471

  7. 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...... snails and one Cleopatra bulimoides snail. Twenty different morphotypes of cercariae were recorded, seven of which appeared not to conform to previously described cercariae from Africa. Xiphidiocercariae type 1 was the most common type of cercariae recovered, accounting for 44.3 % of all infections...... intermediate hosts as the schistosomes. Further studies should be conducted to determine whether some of these trematodes could be manipulated for the biological control of schistosomiasis....

  8. 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

    Directory of Open Access Journals (Sweden)

    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.

  9. 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

  10. 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

    Directory of Open Access Journals (Sweden)

    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.

  11. 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。

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

    Directory of Open Access Journals (Sweden)

    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. 

  13. 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

    International Nuclear Information System (INIS)

    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 (EC5015min = 6,23 mg L-1). In tests with Daphnia similis, the dye RPB was slightly toxic in its pattern form, sulphatoethylsulphone, (CE5048h = 91,25 mg L-1) and showed no toxicity in other chemical forms. However, the RA3R dye was toxic to the dafnids and the vinylsulphone form very toxic (EC5048h = 0,54 mg L-1). No toxicity was observed in Biomphalaria glabrata assays. Chronic toxicity was assessed with the

  14. 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

  15. 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

    Directory of Open Access Journals (Sweden)

    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

  16. Atividade moluscicida da mistura de ácidos 6-n-alquil salicílicos (ácido anacárdico e dos seus complexos com cobre (II e chumbo (II

    Directory of Open Access Journals (Sweden)

    Nelymar Martineli Mendes

    1990-12-01

    Full Text Available Foi comparada, em laboratório, a atividade moluscicida do extrato hexânico da casca da castanha do caju - Anacardium occidentalel L. (EHCCC, do complexo de cobre (II, docomplexo de chumbo (II e do ácido anacárdico com objetivo de encontrar entre eles um produto que apresentasse maior estabilidade que o ácido anacárdico. Este foi preparado tratando o EHCCC com hidróxido de chumbo (II ou com o sulfato de cobre mais hidróxido de sódio ou com hidróxido de cobre (II. Em seguida, o complexo de chumbo (II ou os complexos de cobre (IIpreparados foram tratados com uma solução de ácido sulfúrico diluída. As misturas dos dez produtos obtidos foram testadas sobre caramujos adultos de Biomphalaria glabrata nas concentrações de la 10 ppm. Os mais ativos foram o complexo de cobre (II, obtido com sulfato de cobre mais hidróxido de sódio, e o ácido anacárdico (hidróxido de chumbo que apresentaram atividade a partir da concentração de 4 ppm. O teor de chumbo do ácido anacárdico (hidróxido de chumbo foi acima das normas recomendadas pelos Padrões de Saúde Pública dos Estados Unidos.The molluscicide activity of hexanic extract from Anacardium occidental L. (cashew nutshell, 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 I 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 4ppm. The anacardic acid's lead content was above the limits accepted by the United

  17. 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

    Directory of Open Access Journals (Sweden)

    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.

  18. 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

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

    International Nuclear Information System (INIS)

    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 60Co, 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 60Co 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 analysis

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

    Directory of Open Access Journals (Sweden)

    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

  1. 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

    Directory of Open Access Journals (Sweden)

    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.

  2. Fungal Planet description sheets: 214-280.

    Science.gov (United States)

    Crous, P W; Shivas, R G; Quaedvlieg, W; van der Bank, M; Zhang, Y; Summerell, B A; Guarro, J; Wingfield, M J; Wood, A R; Alfenas, A C; Braun, U; Cano-Lira, J F; García, D; Marin-Felix, Y; Alvarado, P; Andrade, J P; Armengol, J; Assefa, A; den Breeÿen, A; Camele, I; Cheewangkoon, R; De Souza, J T; Duong, T A; Esteve-Raventós, F; Fournier, J; Frisullo, S; García-Jiménez, J; Gardiennet, A; Gené, J; Hernández-Restrepo, M; Hirooka, Y; Hospenthal, D R; King, A; Lechat, C; Lombard, L; Mang, S M; Marbach, P A S; Marincowitz, S; Marin-Felix, Y; Montaño-Mata, N J; Moreno, G; Perez, C A; Pérez Sierra, A M; Robertson, J L; Roux, J; Rubio, E; Schumacher, R K; Stchigel, A M; Sutton, D A; Tan, Y P; Thompson, E H; van der Linde, E; Walker, A K; Walker, D M; Wickes, B L; Wong, P T W; Groenewald, J Z

    2014-06-01

    Novel species of microfungi described in the present study include the following from South Africa: Cercosporella dolichandrae from Dolichandra unguiscati, Seiridium podocarpi from Podocarpus latifolius, Pseudocercospora parapseudarthriae from Pseudarthria hookeri, Neodevriesia coryneliae from Corynelia uberata on leaves of Afrocarpus falcatus, Ramichloridium eucleae from Euclea undulata and Stachybotrys aloeticola from Aloe sp. (South Africa), as novel member of the Stachybotriaceae fam. nov. Several species were also described from Zambia, and these include Chaetomella zambiensis on unknown Fabaceae, Schizoparme pseudogranati from Terminalia stuhlmannii, Diaporthe isoberliniae from Isoberlinia angolensis, Peyronellaea combreti from Combretum mossambiciensis, Zasmidium rothmanniae and Phaeococcomyces rothmanniae from Rothmannia engleriana, Diaporthe vangueriae from Vangueria infausta and Diaporthe parapterocarpi from Pterocarpus brenanii. Novel species from the Netherlands include: Stagonospora trichophoricola, Keissleriella trichophoricola and Dinemasporium trichophoricola from Trichophorum cespitosum, Phaeosphaeria poae, Keissleriella poagena, Phaeosphaeria poagena, Parastagonospora poagena and Pyrenochaetopsis poae from Poa sp., Septoriella oudemansii from Phragmites australis and Dendryphion europaeum from Hedera helix (Germany) and Heracleum sphondylium (the Netherlands). Novel species from Australia include: Anungitea eucalyptorum from Eucalyptus leaf litter, Beltraniopsis neolitseae and Acrodontium neolitseae from Neolitsea australiensis, Beltraniella endiandrae from Endiandra introrsa, Phaeophleospora parsoniae from Parsonia straminea, Penicillifer martinii from Cynodon dactylon, Ochroconis macrozamiae from Macrozamia leaf litter, Triposporium cycadicola, Circinotrichum cycadis, Cladosporium cycadicola and Acrocalymma cycadis from Cycas spp. Furthermore, Vermiculariopsiella dichapetali is described from Dichapetalum rhodesicum (Botswana), Ophiognomonia

  3. Land use effect on invertebrate assemblages in Pampasic streams (Buenos Aires, Argentina).

    Science.gov (United States)

    Solis, Marina; Mugni, Hernán; Hunt, Lisa; Marrochi, Natalia; Fanelli, Silvia; Bonetto, Carlos

    2016-09-01

    Agriculture and livestock may contribute to water quality degradation in adjacent waterbodies and produce changes in the resident invertebrate composition. The objective of the present study was to assess land use effects on the stream invertebrate assemblages in rural areas of the Argentine Pampa. The four sampling events were performed at six sites in four streams of the Pampa plain; two streams were sampled inside a biosphere reserve, and another one was surrounded by extensive livestock fields. The fourth stream was sampled at three sites; the upstream site was adjacent to agricultural plots, the following site was adjacent to an intensive livestock plot and the downstream site was adjacent to extensive breeding cattle plots. Higher pesticide concentrations were found at the site adjacent to agricultural plots and higher nutrient concentrations at the sites adjacent to agricultural and intensive breeding cattle plots. The invertebrate fauna were also different at these sites. Multivariate analysis showed a relationship between nutrient concentrations and taxonomic composition. Amphipoda (Hyalella curvispina) was the dominant group in the reserve and extensive breeding cattle sites, but was not present in the agricultural site. Also, Chironomidae were absent from the agricultural site while present at other sites. Gasteropoda (Biomphalaria peregrina), Zygoptera, and Hirudinea were dominant at the most impacted agricultural and intensive breeding cattle sites. PMID:27581006

  4. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  7. 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.

  8. 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.

  9. Efficacy of temperature, and two commonly used molluscicides and fertilizers on Fasciola gigantica eggs.

    Science.gov (United States)

    Hassan, Aly A; Shoukary, Nahla M; Ismail, Nahed M M

    2008-08-01

    This study evaluated the effect of temperature, molluscicides (Copper sulphate and Niclosamide), fertilizers (Superphosphate and Ammonium sulphate) on the hatchability of Fasciola gigantica eggs. The results showed that hatchability decreased to 4% when eggs were incubated in bile secretion at 37 degrees C for 5 days and to 1.4% for 10 days, but few eggs incubated in water at 37 degrees C hatched. Bile secretion at 37 degrees C was a poor medium for in-vitro egg preservation. But, hatching occurred only when eggs were transferred to water at 26 degrees C. Temperature fluctuation from 26-4 degrees C or from 32-4 degrees C had an inhibitory effect on embryos development (35.2% & 32.3%, respectively) as compared to controls (60% & 63.9%, respectively). The incubation period (19 & 17 days) was higher than controls (14 & 12 days, respectively). The LC50 & LC90 of Copper sulphate and Niclosamide against Biomphalaria alexandrina and Lymnaea natalenesis had no toxic effect on Fasciola eggs. The higher concentrations of Copper sulphate (30 ppm) and Niclosamide (1 ppm) slightly lower eggs hatchability rate than controls. The rate decreased by increasing the exposure time from 3 to 6 hours with both molluscicides. Ammonium sulphate had a lethal effect on eggs, but Superphosphate had some inhibitory effect on egg development, which increased by increasing Superphosphate concentration or with the prolongation of the exposure time. PMID:18853633

  10. 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. PMID:18383803

  11. 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.

  12. 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

    2016-06-01

    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. PMID:27162339

  13. 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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    Mauricio Carvalho de Vasconcellos

    2003-10-01

    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.

  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. Digenetic larvae in Schistosome snails from El Fayoum, Egypt with detection of Schistosoma mansoni in the snail by PCR.

    Science.gov (United States)

    Aboelhadid, Shawky M; Thabet, Marwa; El-Basel, Dayhoum; Taha, Ragaa

    2016-09-01

    The present study aims to detect the digenetic larvae infections in Bulinus truncatus and Biomphalaria alexandrina snails and also PCR detection of Schistosoma mansoni infection. The snails were collected from different branches of Yousef canal and their derivatives in El Fayoum Governorate. The snails were investigated for infection through induction of cercarial shedding by exposure to light and crushing of the snails. The shed cercariae were S. mansoni, Pharyngeate longifurcate type I and Pharyngeate longifurcate type II from B. alexandrina, while that found in B. truncatus were Schitosoma haematobium and Xiphidiocercaria species cercariae. The seasonal prevalence of infection was discussed. Polymerase chain reaction was used for the detection of S. mansoni in the DNA from field collected infected and non infected snails. The results of PCR showed that the pool of B. alexandrina snails which shed S. mansoni cercariae in the laboratory, gave positive reaction in the samples. Pooled samples of field collected B. alexandrina that showed negative microscopic shedding of cercariae gave negative and positive PCR in a consecutive manner. Accordingly, a latent infection in the snail (negative microscopic) could be detected by using PCR. PMID:27605774

  16. Experimental evaluation of Candonocypris novaezelandiae (Crustacea: Ostracoda) in the biocontrol of Schistosomiasis mansoni transmission

    Science.gov (United States)

    Yousif, Fouad; Hafez, Sherif; El Bardicy, Samia; Tadros, Menerva; Taleb, Hoda Abu

    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 risky sites could suppress the transmission of the disease. PMID:23620849

  17. 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.

  18. Determination of the lethal doses LD50 and LD90 of Euphorbia splendens var. hislopii latex on Physa cubensis Pfeiffer

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    Aloysio da Silva Ferrão Filho

    2012-12-01

    Full Text Available The genus Physa are among the most common and widespread fresh-water snails and are frequently associated with the genus Lymnaea and Biomphalaria, typically occupying the same habitat and being hosts of trematodes that can cause disease in humans. Several studies have evaluated the control of snails through the use of plant-derived molluscicides; however, few such studies exist regarding the genus Physa. Determining the correct lethal doses of [latex of Euphorbia splendens] is important for the control of the Physa cubensis snail. In one experimental model, 150 snails from Jacarepaguá, Rio de Janeiro, RJ were used. After acclimatization for 72 hours, the snails were divided into groups of 10 and placed into beakers containing different doses, each at a temperature of 26±1ºC and a relative humidity of 80±10%. The results demonstrated LD50 of 1.08 µL/L and LD90 of 3.41 µL/L, without significant changes in the physical or chemical parameters of the solutions. We conclude that E. splendens latex had a significant effect on P. cubensis in the laboratory setting.

  19. 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)

  20. 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.

  1. Laboratory evaluation of B-2 as a molluscicide in the control of the snail intermediate hosts of schistosomiasis in South Africa.

    Science.gov (United States)

    Joubert, P H; Pretorius, S J

    1991-08-01

    There is a continuous need for the development and evaluation of new, inexpensive but highly effective molluscides for the control of freshwater snails acting as intermediate hosts of schistomiasis. For this reason B-2 (Hokko Chemical Industry Co. Ltd, Japan), also called Phebrol (sodium 2,5-dichloro-4-bromophenol), was evaluated in our laboratory as a candidate molluscicide for the control of freshwater snails in South Africa. Bulinus africanus and Biomphalaria pfeifferi, intermediate hosts of Schistosoma haematobium and Schistosoma mansoni respectively, were exposed to different B-2 concentrations for 24 and 48 hours. An indigenous fish species, Oreochromis mossambicus, which is common in local schistosomiasis endemic areas, was also exposed to the molluscicide. The calculated values obtained from a probit analysis (LC50, 24 hours: B. africanus = 2.6 mg 1(-1) and B. pfeifferi = 2.9 mg 1(-1), indicated that these species from southern Africa are less sensitive to B-2 than are B. truncatus and B. pfeifferi from northern Africa, which in turn are less sensitive than the Oncomelania spp. from Japan, China and the Philippines. It is expected that molluscicidal levels of B-2 would be harmful to O. mossambicus populations. Although B-2 has a marked potential for snail control in South Africa, niclosamide (Bayluscide) remains the molluscicide of choice. PMID:1796888

  2. OMNIHAB - a controlled environmental system for application in gravitational biology

    Science.gov (United States)

    Anken, Ralf; Hilbig, Reinhard; Anken, Ralf; Lebert, Michael; Häder, Donat

    Several "closed" habitats have been designed in the past for experiments with unicellular organisms as well as with multicellular animals and plants under long-term microgravity. Some of these environmental systems were flown successfully. The bioregenerative C.E.B.A.S.- Minimodul allowed the maintenance of higher plants (Ceratophyllum sp.), mollusks (Biomphalaria glabrata) and fish (swordtail Xiphophorus helleri, cichlid fish Oreochromis mossambicus) under spaceflight conditions (STS-89, STS-90 Neurolab, STS-107). A much simpler and smaller system, the OMEGAHAB, was successfully employed on the FOTON M-3 flight, containing cichlid fish larvae and unicellular algae (Euglena gracilis). Further aquatic habitats are under development (e.g., AquaHab, another aquatic research module especially dedicated to ground based, application-oriented research). These systems tend to be specialized, minimal ecosystems with limited research potential. Therefore, we propose to develop a controlled, multi-modular hardware to increase the diversity of experimental species to be flown together. Currently, a variety of plant and animal species are used as model systems. Combining as many of them as possible (and conducting a most effective sample-sharing among the different working groups) will strongly improve the cost-benefit ratio and thus effectiveness of a space- flight experiment in utilising limited resources at the maximum. The concept of OMNIHAB, an aquatic life support system comprising exchangeable modules, will be presented at the meeting.

  3. 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.

  4. 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

    2016-06-01

    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.

  5. 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.

  6. 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.

  7. 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.

  8. New insights into parental effects and toxicity: Mate availability and diet in the parental environment affect offspring responses to contaminants

    International Nuclear Information System (INIS)

    Parental effects manifest as alterations in offspring phenotype resulting from the parental phenotype and/or parental environment. We evaluated the effects of parental diet quality and mating strategy on the toxicant tolerance of offspring in Biomphalaria glabrata snails. We raised snails either individually (self-fertilizing) or in groups of three (outcrossing) on a diet of uncooked lettuce, fish food, cooked lettuce, or cooked lettuce plus fish food. We then exposed their offspring to cadmium and malathion challenges. Cadmium tolerance varied with parental diet and was greater in the offspring of outcrossing snails than self-fertilizing snails. Malathion tolerance was not affected by parental diet but was greater in the offspring of outcrossing snails. These results indicate that offspring responses to stressors are heavily influenced by parental experience, but may depend on the specific stressor and the mechanism of action and/or detoxification. -- Highlights: •We reared parental snails either alone or in groups and fed them one of four diets. •We exposed their juvenile offspring to cadmium and malathion survival challenges. •Outcrossing increased toxicant tolerance of juveniles compared to self-fertilizing. •Parental diet affected juvenile offspring tolerance to cadmium but not malathion. •Toxicant characteristics likely influenced parental effects on toxicant tolerance. -- Both parental diet composition and mating strategy can significantly alter the toxicant tolerance of offspring, and toxicant characteristics likely influence the probability of parental effects

  9. Saponins from Swartzia langsdorffii: biological activities

    Directory of Open Access Journals (Sweden)

    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.

  10. [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.

  11. 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.

  12. 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.

  13. 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.

  14. 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. PMID:26012228

  15. 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. PMID:22983292

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

    Science.gov (United States)

    Enk, Martin Johannes; Amaral, Graciela Larissa; Costa e Silva, Matheus Fernandes; Silveira-Lemos, Denise; Teixeira-Carvalho, Andréa; Martins-Filho, Olindo Assis; Correa-Oliveira, Rodrigo; Gazinnelli, Giovanni; Coelho, Paulo Marcos Zech; Massara, Cristiano Lara

    2010-07-01

    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. PMID:20721505

  17. Acute schistosomiasis outbreak in the metropolitan area of Belo Horizonte, Minas Gerais: alert about the risk of unnoticed transmission increased by growing rural tourism.

    Science.gov (United States)

    Enk, Martin J; Amorim, Amanda; Schall, Virginia T

    2003-09-01

    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. PMID:14595449

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

    Directory of Open Access Journals (Sweden)

    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.

  19. 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

    Directory of Open Access Journals (Sweden)

    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.

  20. Acute schistosomiasis outbreak in the metropolitan area of Belo Horizonte, Minas Gerais: alert about the risk of unnoticed transmission increased by growing rural tourism

    Directory of Open Access Journals (Sweden)

    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.

  1. Micronuclei as biomarkers of genotoxicity of gamma radiation in aquatic environments

    International Nuclear Information System (INIS)

    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 60Co. 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)

  2. 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.

  3. 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.

  4. 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

  5. The prolonged use of niclosamide as a molluscicide for the control of Schistosoma mansoni Uso prolongado da niclosamida como moluscicida para o controle do Schistosoma mansoni

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    Pedro Coura-Filho

    1992-10-01

    Full Text Available Applications of niclosamide at three-monthly intervals were undertaken for 14 years in foci of Biomphalaria glabrata in the water sources of Peri-Peri (Capim Branco, MG. All the residents of the area were submitted to an annual fecal examination (Kato/Katz and those individuals eliminating Schistosoma mansoni eggs were treated with oxamniquine. A malacological survey was undertaken at three-monthly intervals by means of ten scoops with a perforated ladle each ten metres along the two banks of the ditches and streams of the region. Where snails were found, molluscicide was applied by means of dripping or aspersion using a 3 ppm aqueous suspension of niclosamide. Initially, a mean of 14.3% of snails in the region were found to be eliminating cercariae. Following the first four applications of molluscicide, this was reduced to 0.0% and maintained at about 1.5% throughout the program. Thus, there was a continued possibility of schistosomiasis transmission in the area and it was observed that the population of snails reestablished itself within three months of molluscicide application. The results obtained in this study do not encourage the continual use of niclosamide as the only method of control of schistosomiasis.Aplicações trimestrais de niclosamida foram realizadas catorze anos em focos de Biomphalaria glabrata nas coleções hídricas de Peri-Peri, (Capim Branco, MG. Anualmente, os residentes da área eram submetidos a um exame coproscópio (Kato-Katz e os que eliminavam ovos de Schistosoma mansoni nas fezes eram tratados com oxarnniquine. O levantamento malacológico trimestral foi realizado através de dez conchadas a cada dez metros nas duas margens das valas e córregos da região. Onde eram encontrados caramujos aplicava-se o moluscicida pela técnica de gotejamento ou aspersão de suspensão aquosa da niclosamida a 3 ppm. O índice médio de caramujos eliminando cercarias na região era de 14,3%. Após as quatro primeiras aplica

  6. Alimentação e fecundidade de planorbídeos criados em laboratórios: IV - Helisoma duryi (Wetherby, 1879. (Pulmonata, Planorbidae Feeding and fecundity of planorbidae bred in the laboratory: IV - Helisoma duryi (Wetherby, 1879. (Putmonata, Planorbidae

    Directory of Open Access Journals (Sweden)

    Roberto Milward-de-Andrade

    1978-03-01

    Full Text Available Utilizando dois tipos distintos de alimentos: "Aquariol" (alimento utilizado para alimentar peixes ornamentais e alface, isolados e associados, na criação de Helisoma (Seminolina duryi (Wetherby, 1879 em laboratório, foi verificado que; 1. Os caramujos alimentados com alface fresca liberaram, em 17 semanas, 826 desovas on 17.707 ovos. 2. Os especimens alimentados com "aquariol" depuseram 534 desovas on 11.361 ovos. 3. O oferecimento dos dois materiais associados resultou no aumento da fertilidade, obtendo-se, assim, 1.355 desovas ou 34.645 ovos. 4. Em termos médios, cada conjunto de quinze exemplares (com 10 a 14 mm de diâmetro liberou, diariamente, 95,5 - 148,8 e 291,1 ovos/dia, segundo o tipo de alimento consumido: "aquariol", alface fresca, ou ambos associados. O número de desovas/dia, na mesma ordem enunciada, foi de 4,5 - 6,9 e 11,4, respectivamente. 5, Os exemplares utilizados descendiam de uma cepa supostamente recém introduzida no município de Formosa, GO (Brasile originária da Região Neártica (EUA. Foi comentada a possibilidade de controle biológico de diferentes espécies de Biomphalaria através de H. duryi - questão sobre a qual vêm desenvolvendo investigações biológicas e ecológicas.After experiments with two types of food, lettuce and "aquariol" (i.e., animal protein flour for ornamental fish both isolated and in association, in the breeding of Helisoma (Seminolina duryi (Wetherby, 1879, the following results: were obtained: 1. Snails fed on fresh lettuce yielded, at the end of 17 weeks, 826 egglavings or, better, 17,707 eggs. 2. Specimens fed on "aquariol" produced 534 egg clutches or 11,361 eggs. 3. Snails fed on both fresh lettuce and "aquariol" happened to provide 1,355 egglayings or 34,645 eggs. 4. On the average, each batch of 15 snails or three group of 5 ones (each specimen displyaing 10-14 mm diameter liberated 95.5, 148.8 and 291.1 eggs/day, in accordance with their type of meal - lettuce, "aquariol" or

  7. 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

    Directory of Open Access Journals (Sweden)

    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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. Long-term effect of mass chemotherapy, transmission and risk factors for Schistosoma mansoni infection in very low endemic communities of Venezuela.

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    Hofstede, Stefanie N; Tami, Adriana; van Liere, Genevieve A F S; Ballén, Diana; Incani, Renzo N

    2014-12-01

    The prevalence of Schistosoma mansoni infection in Venezuela has changed from high to low due mostly to successful control activities, including mass chemotherapy and molluscicide applications. This study examined the impact of mass chemotherapy on S. mansoni transmission and risk factors for infection 12 years after administration of praziquantel in Venezuela. Two relatively isolated rural communities were studied, one with snail control (Manuare) and the second without (Los Naranjos). A cross-sectional survey of randomly selected households included 226 (Manuare) and 192 (Los Naranjos) consenting participants. S. mansoni prevalence was determined using a combination of coprological (Kato-Katz) and serological (circumoval precipitin test, alkaline phosphatase immunoassay and Western blot) tests. Data on epidemiological and socioeconomic risk factors were obtained through individual structured interviews. Univariate analysis and multivariate logistic regression models identified independent risk factors for infection. Water sites were examined for the presence of Biomphalaria glabrata snails. Only one participant was positive by coprology. The overall prevalences according to the combined tests were 32.7% in Manuare and 26.6% in Los Naranjos. Lower prevalences (12.7% in Manuare and 13.2% in Los Naranjos) were found in children 25 years), contact with specific water sites, and being a farmer/non-specialised worker. Mass treatment with praziquantel applied once to endemic communities led to an important and long-lasting sustained reduction of S. mansoni infections independent of the application of snail control. A degree of low active transmission of S. mansoni persisted in the treated areas which was associated with similar factors in both communities. PMID:25128702

  14. Systematic Review and Meta-analysis of the Impact of Chemical-Based Mollusciciding for Control of Schistosoma mansoni and S. haematobium Transmission.

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    Charles H King

    2015-12-01

    Full Text Available Programs for schistosomiasis control are advancing worldwide, with many benefits noted in terms of disease reduction. Yet risk of reinfection and recurrent disease remain, even in areas with high treatment coverage. In the search for means to better prevent new Schistosoma infections, attention has returned to an older strategy for transmission control, i.e., chemical mollusciciding, to suppress intermediate host snail species responsible for S. mansoni and S. haematobium transmission. The objective of this systematic review and meta-analysis was to summarize prior experience in molluscicide-based control of Bulinus and Biomphalaria spp. snails, and estimate its impact on local human Schistosoma infection.The review was registered at inception with PROSPERO (CRD42013006869. Studies were identified by online database searches and hand searches of private archives. Eligible studies included published or unpublished mollusciciding field trials performed before January 2014 involving host snails for S. mansoni or S. haematobium, with a primary focus on the use of niclosamide. Among 63 included papers, there was large variability in terms of molluscicide dosing, and treatment intervals varied from 3-52 weeks depending on location, water source, and type of application. Among 35 studies reporting on prevalence, random effects meta-analysis indicated that, on average, odds of infection were reduced 77% (OR 0.23, CI95% 0.17, 0.31 during the course of mollusciciding, with increased impact if combined with drug therapy, and progressively greater impact over time. In 17 studies reporting local incidence, risk of new infection was reduced 64% (RR 0.36 CI95% 0.25, 0.5, but additional drug treatment did not appear to influence incidence effects.While there are hurdles to implementing molluscicide control, its impact on local transmission is typically strong, albeit incomplete. Based on past experience, regular focal mollusciciding is likely to contribute

  15. 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.

  16. 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.

  17. The effects of the herbicide atrazine on freshwater snails.

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    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.

  18. 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.

  19. 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.

  20. 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.

  1. Antiprotozoal and molluscicidal activities of five Brazilian plants

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    M.C.T. Truiti

    2005-12-01

    Full Text Available Leishmaniasis, Chagas' disease and schistosomiasis (bilharzia are parasitic diseases with wide distribution on the American continent, affecting millions of people. In the present study, biological assays for antiprotozoal and molluscicidal activities were carried out with ethanolic extracts of plant species from the Brazilian part of the Upper Paraná River. Crude extracts were obtained by percolation with absolute ethanol from the leaves of Cayaponia podantha Cogn., Nectandra falcifolia (Nees Castiglioni and Paullinia elegans Cambess., as well as from the aerial parts of Helicteres gardneriana St. Hil. & Naud. and Melochia arenosa Benth., all belonging to genera used in folk medicine. Trypanocidal activity of plants was assayed on epimastigote cultures in liver infusion tryptose. Anti-leishmanial activity was determined over cultures of promastigote forms of the parasite in Schneider's Drosophila medium. Microscopic countings of parasites, after their incubation in the presence of different concentrations of the crude extracts, were made in order to determine the percentage of growth inhibition. C. podantha and M. arenosa, at a concentration of 10 µg/mL, showed 90.4 ± 11.52 and 88.9 ± 2.20% growth inhibition, respectively, of epimastigote forms of Trypanosoma cruzi, whereas N. falcifolia demonstrated an LD50 of 138.5 µg/mL against promastigote forms of Leishmania (Viannia braziliensis. Regarding molluscicidal activity, the acute toxicity of the extracts on Biomphalaria glabrata was evaluated by a rapid screening procedure. M. arenosa was 100% lethal to snails at 200 µg/mL and showed an LD50 of 143 µg/mL. Screening of plant extracts represents a continuous effort to find new antiparasitic drugs.

  2. 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

  3. Genotypic variation in host response to infection affects parasite reproductive rate.

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    Tavalire, Hannah F; Blouin, Michael S; Steinauer, Michelle L

    2016-02-01

    Parasite fitness is largely influenced by a variation in host response due to the host's genetic background. Here we investigated the impact of host genotype on pathogen success in the snail vector of its castrating parasite, Schistosoma mansoni. We infected five inbred lines of Biomphalaria glabrata with two infection doses and followed their growth, reproductive output and parasite production throughout the course of infection. There was no difference in resistance to infection among inbred lines, but lines varied in their responses to infection and the numbers of parasites produced. Snails did not compensate for castration by increasing their fecundity during the early phase of infection (fecundity compensation). However, some lines were able to delay parasite shedding for up to 30 weeks, thus prolonging reproduction before the onset of castration. Here we propose this strategy as a novel defense against castrating pathogens in snails. Gigantism, a predicted outcome of castration due to energy reallocation, occurred early in infection (gigantism were also characterised by a high parasite production rate and low survivorship, perhaps indicating energy reallocation into parasite production and costly immune defense. We observed no differences in total parasite production among lines throughout the entire course of infection, although lines differed in their parasite reproductive rate. The average rate of parasite production varied among lines from 1300 to 2450 cercariae within a single 2h shedding period, resulting in a total production of 6981-29,509 cercariae over the lifetime of a single snail. Regardless of genetic background, snail size was a strong predictor of parasite reproduction: each millimetre increase in snail size at the time of the first shed resulted in up to 3500 more cercariae over the lifetime of the snail. The results of this study provide a detailed picture of variation in hosts' responses to infection and the resulting impacts on parasite

  4. 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.

  5. Glycotope sharing between snail hemolymph and larval schistosomes: larval transformation products alter shared glycan patterns of plasma proteins.

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    Timothy P Yoshino

    Full Text Available Recent evidence supports the involvement of inducible, highly diverse lectin-like recognition molecules in snail hemocyte-mediated responses to larval Schistosoma mansoni. Because host lectins likely are involved in initial parasite recognition, we sought to identify specific carbohydrate structures (glycans shared between larval S. mansoni and its host Biomphalaria glabrata to address possible mechanisms of immune avoidance through mimicry of elements associated with the host immunoreactivity. A panel of monoclonal antibodies (mABs to specific S. mansoni glycans was used to identify the distribution and abundance of shared glycan epitopes (glycotopes on plasma glycoproteins from B. glabrata strains that differ in their susceptibilities to infection by S. mansoni. In addition, a major aim of this study was to determine if larval transformation products (LTPs could bind to plasma proteins, and thereby alter the glycotopes exposed on plasma proteins in a snail strain-specific fashion. Plasma fractions ( 100 kDa from susceptible (NMRI and resistant (BS-90 snail strains were subjected to SDS-PAGE and immunoblot analyses using mAB to LacdiNAc (LDN, fucosylated LDN variants, Lewis X and trimannosyl core glycans. Results confirmed a high degree of glycan sharing, with NMRI plasma exhibiting a greater distribution/abundance of LDN, F-LDN and F-LDN-F than BS-90 plasma ( 100 kDa fraction. Our data suggest that differential binding of S. mansoni LTPs to plasma proteins of susceptible and resistant B. glabrata strains may significantly impact early anti-larval immune reactivity, and in turn, compatibility, in this parasite-host system.

  6. Glycotope sharing between snail hemolymph and larval schistosomes: larval transformation products alter shared glycan patterns of plasma proteins.

    Science.gov (United States)

    Yoshino, Timothy P; Wu, Xiao-Jun; Liu, Hongdi; Gonzalez, Laura A; Deelder, André M; Hokke, Cornelis H

    2012-01-01

    Recent evidence supports the involvement of inducible, highly diverse lectin-like recognition molecules in snail hemocyte-mediated responses to larval Schistosoma mansoni. Because host lectins likely are involved in initial parasite recognition, we sought to identify specific carbohydrate structures (glycans) shared between larval S. mansoni and its host Biomphalaria glabrata to address possible mechanisms of immune avoidance through mimicry of elements associated with the host immunoreactivity. A panel of monoclonal antibodies (mABs) to specific S. mansoni glycans was used to identify the distribution and abundance of shared glycan epitopes (glycotopes) on plasma glycoproteins from B. glabrata strains that differ in their susceptibilities to infection by S. mansoni. In addition, a major aim of this study was to determine if larval transformation products (LTPs) could bind to plasma proteins, and thereby alter the glycotopes exposed on plasma proteins in a snail strain-specific fashion. Plasma fractions ( 100 kDa) from susceptible (NMRI) and resistant (BS-90) snail strains were subjected to SDS-PAGE and immunoblot analyses using mAB to LacdiNAc (LDN), fucosylated LDN variants, Lewis X and trimannosyl core glycans. Results confirmed a high degree of glycan sharing, with NMRI plasma exhibiting a greater distribution/abundance of LDN, F-LDN and F-LDN-F than BS-90 plasma (LTPs significantly altered the reactivity of specific mABs to shared glycotopes on blots, mainly through the binding of LTPs to plasma proteins resulting in either glycotope blocking or increased glycotope attachment to plasma. Many LTP-mediated changes in shared glycans were snail-strain specific, especially those in the 100 kDa fraction. Our data suggest that differential binding of S. mansoni LTPs to plasma proteins of susceptible and resistant B. glabrata strains may significantly impact early anti-larval immune reactivity, and in turn, compatibility, in this parasite-host system. PMID:22448293

  7. 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.

  8. 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.

  9. Experimental evaluation of Candonocypris novaezelandiae(Crustacea:Ostracoda) in the biocontrol of Schistosomiasis mansoni transmission

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    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.

  10. 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.

  11. 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

  12. Guest Editorial

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    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

  13. Efficacy of praziquantel and reinfection patterns in single and mixed infection foci for intestinal and urogenital schistosomiasis in Cameroon.

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    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.

  14. Laboratory assessment of molluscicidal and cercariacidal effects of Glinus lotoides fruits

    Science.gov (United States)

    2014-01-01

    Background The negative impact of synthetic molluscicides on the environment and their high cost necessitated search for an alternative approach of using plant extracts for the control of schistosomiasis. The objective of this study was, therefore, to evaluate aqueous and ethyl acetate crude extracts of Glinus lotoides fruits for their cercariacidal activity and molluscicidal effect against schistosome snail intermediate hosts. Methods Assessment of the molluscicidal activity against Biomphalaria pfeifferi was made by immersion method in accordance with WHO guideline. The results of mortality were statistically analyzed using probit analysis. The attenuating effect of the plant on Schistosoma mansoni cercariae was determined using establishment of adult worms as a parasitological parameter post exposure. Results The 24 and 48 hour-LC50 values for the aqueous extract of G. lotoides fruits were 47.1 and 44.1 mg/L, respectively, whereas that of ethyl acetate were 66.1 and 59.6 mg/L, respectively. The 24 and 48 hour LC90 values for the aqueous extract of G. lotoides fruits were 56.96 and 51.0 mg/L, respectively, while that of ethyl acetate were 77.2 and 70.0 mg/L, respectively. The in vitro cercariacidal activity was determined after 2 hrs of exposure to the aqueous plant extract. It was found out that the LC50 and LC90 values were 18.7 and 41.7 mg/L, respectively. Besides, infectivity of Schistosoma mansoni cercariae to mice was determined by exposing mice to cercariae pre-treated with the sub-lethal concentrations (3.7, 11.6 and 18.7 mg/L) of the aqueous extract. A significant reduction in worm burden in mice was obtained at 11.6 mg/L (p molluscicidal activity against B. pfeifferi snails and cercariacidal activity against S. mansoni. Yet, further comprehensive evaluation is recommended for the possible use of G. lotoides against B. pfeifferi and the schistosome parasite. PMID:24713133

  15. Laboratory assessment of the molluscicidal and cercariacidal activities of Balanites aegyptiaca

    Science.gov (United States)

    Molla, Eshetu; Giday, Mirutse; Erko, Berhanu

    2013-01-01

    Objective To assess the molluscicidal and cercariacidal activities of aqueous extracts of Balanites 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

  16. Long term study on the effect of mollusciciding with niclosamide in stream habitats on the transmission of schistosomiasis mansoni after community-based chemotherapy in Makueni District, Kenya

    Science.gov (United States)

    2013-01-01

    Background Schistosoma mansoni infection is a persistent public health problem in many Kenyan communities. Although praziquantel is available, re-infection after chemotherapy treatment is inevitable, especially among children. Chemotherapy followed by intermittent mollusciciding of habitats of Biomphalaria pfeifferi, the intermediate host snail, may have longer term benefits, especially if timed to coincide with natural fluctuations in snail populations. Methods In this cohort study, the Kambu River (Intervention area) was molluscicided intermittently for 4 years, after mass chemotherapy with praziquantel in the adjacent community of Darajani in January 1997. The nearby Thange River was selected as a control (Non-intervention area), and its adjacent community of Ulilinzi was treated with praziquantel in December 1996. Snail numbers were recorded monthly at 9–10 sites along each river, while rainfall data were collected monthly, and annual parasitological surveys were undertaken in each village. The mollusciciding protocol was adapted to local conditions, and simplified to improve prospects for widespread application. Results After the initial reduction in prevalence attributable to chemotherapy, there was a gradual increase in the prevalence and intensity of infection in the non-intervention area, and significantly lower levels of re-infection amongst inhabitants of the intervention area. Incidence ratio between areas adjusted for age and gender at the first follow-up survey, 5 weeks after treatment in the non-intervention area and 4 months after treatment in the intervention area was not significant (few people turned positive), while during the following 4 annual surveys these ratios were 0.58 (0.39-0.85), 0.33 (0.18-0.60), 0.14 (0.09-0.21) and 0.45 (0.26-0.75), respectively. Snail numbers were consistently low in the intervention area as a result of the mollusciciding. Following termination of the mollusciciding at the end of 2000, snail populations and

  17. 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

  18. [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

  19. Ciclo Vital de Schistosoma mansoni através do Holochilus brasiliensis (Desmarest, 1818 em ambiente semi-natural (Trematoda, Shistosomatidae; Rodentia, Cricetidae

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    Omar dos Santos Carvalho

    1976-10-01

    Full Text Available Junto ao Lago da Pampulha, Belo Horizonte, MG, foram capturados (julho/72-novembro/73 28 exemplares de Holochilus brasiliensis, dos quais 11 (39,3% eliminavam nas fezes ovos viáveis de S. mansoni. Miracídios da cepa mencionada ("H" infectaram Biomphalaria glabrata e as cercárias obtidas também infectaram camundongos albinos, recuperando-se, ao final do experimento, 35,3% de vermes adultos. Por outro lado, cercárias de cepa humana ("LE" de S. mansoni infectaram sete exemplares de H. brasiliensis, nascidos em laboratório, recuperando-se no fim de 60 dias, 30,5% de vermes adultos. Estudos anatomapatológicos de H. brasiliensis demonstraram infecção generalizada, encontrando-se granuloma no esôfago, estômago, intestino (delgado e grosso, fígado, baço, pâncreas e linfonodos abdominais. Espessamentos fibrosos da íntima da veia porta, granulomas em espaços porta e fibrose incipiente dos espaços porta e interlobular foram lesões decorrentes da presença de ovos de S. mansoni encontrados no fígado. Em ambiente semi-natural, foi possível fechar o ciclo do S. mansoni sem direta participação humana, utilizando-se B. glabrata experimentalmente infectadas com trematódeos da cepa "LE", H. brasiliensis nascidos em laboratório e B. glabrata nascida no ambiente semi-natural estabelecido. Verificou-se que ambas as cepas ("H" e "LE" comportaram-se de maneira análoga, não sendo verificadas, também, diferenças morfológicas entre os ovos e vermes adultos de ambas. As observações, realizadas no campo e no laboratório demonstraram que o Holochilus brasiliensis é bom hospedeiro de Schistosoma mansoni. Assim, em determinadas áreas e sob certas condições ecológicas, o cricetídeo em questão poderá, efetivamente, integrar-se ao ciclo do trematódeo na natureza, independente ou paralelamente à presença do homem. Assinala-se, finalmente, que o presente trabalho relata o segundo fechamento do ciclo biológico de S. mansoni em condi

  20. The C.E.B.A.S.-Minimodule: Behaviour of an Artificial Aquatic Ecological System During Spaceflight

    Science.gov (United States)

    Bluem, V.; Andriske, M.; Paris, F.; Voeste, D.

    The C.E.B.A.S.-Minimodule, a closed aquatic ecosystem integrated into a middeck locker and consisting of a Zoological (animal tanks), a Botanical (plant bioreactor), a Microbial (bacteria filter) and an Electronic Component (data acquisition/control system) was flown on the STS-89 spaceshuttle mission in January 1998 for 9 days. Preflight the plant bioreactor was loaded with 53 g of Ceratophyllum demersum (coontail) and the animal tanks with 4 adult pregnant females of the fish, Xiphophorus helleri (sword-tails), 200 juveniles of the same species less than 1 week of age, 38 large and 30 juvenile Biomphalaria glabrata water snails. The filter compartment was filled with 200 g of lava grain inoculated with laboratory strains of ammonia-oxidizing bacteria. A ground reference was undertaken with the same biological setup with a delay of 4 d. After an adaptation period of 5 d the system was closed and integrated into the spaceshuttle one day before launch. Video recordings of the animals were automatically taken for 10 minutes in 2-hour periods; the tapes were changed daily by the astronauts. The chemical and physical data for the aquatic system were within the expected range and were closely comparable in comparison to the ground reference. After 9 d under space conditions, the plant biomass increased to 117 g. The plants were all found in very good condition. All 4 adult female fish were retrieved in a good physiological condition. The juvenile fishes had a survival rate of about 33 %. Almost 97 % of the snails had survived and produced more than 250 neonates and 40 spawning packs. All samples were distributed according to a defined schedule and satisfied all scientific needs of the involved 12 principal investigators. This was the first successful spaceflight of an artificial aquatic ecosystem containing vertebrates, invertebrates, higher plants and microorganisms self-sustained by its inhabitants only. C.E.B.A.S. in a modified form and biological setup is a

  1. Radiation Processing of Wastewater and Possibilities for Reuse

    International Nuclear Information System (INIS)

    In the framework of the CRP IPEN has worked on the irradiation and toxicity assessment for the improvement of dyes standard solutions and real complex effluents (textile) in order to achieve recommended quality for reuse of treated effluents during the process as well as for a suitable environmental discharge. Three different types of effluents were submitted to irradiation including standard solution of two reactive dyes (Remazol Black B - RPB and Remazol Orange 3R – R3AR). It was also identified that different chemical formulas of these reactive dyes can contribute to a higher toxic charge during effluents discharges. In general the toxicity control was carried out on crustaceans and luminescent bacteria but a lot of experiments were performed with the aquatic snail Biomphalaria glabrata, this last biological assay was developed at “Instituto Butantan (USP, SP)”. Irradiations and measurements with UV spectrophotometer resulted always on less colored effluents and most often on less toxic liquid residues, after irradiation. Percentage of reductions for toxicity and color depended on the effluent source and the radiation doses applied varied from 1 to 10 kGy. The decoloration of remazol black B and orange 3R solutions was effective for 1kGy and 2.5 kGy which is a relatively low dose and may contribute to a suitable cost for irradiation technology. Since the possibility of different formula of dyes be present at environment exist, the toxicity was measured for all of them and it was noted that vinylsulphone form was the worst in terms of effects for V.fischeri ( Black B 133%) and D.similis (Orange 3R). Regarding biological effects of these remazol dyes after irradiation, this same dye solution resulted at 60% removal only for V.fischeri (not for daphnids) and when treated with 5 kGy and 10 kGy. Irradiation of real textile BVT effluents resulted in good colour removal but the acute toxicity reduction varied widely 97% (0.5kGy), 54% (2.5kGy) and 19% (1.0k

  2. 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

  3. 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

  4. 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

  5. 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

  6. Ciclo Vital de Schistosoma mansoni através do Holochilus brasiliensis (Desmarest, 1818 em ambiente semi-natural (Trematoda, Shistosomatidae; Rodentia, Cricetidae

    Directory of Open Access Journals (Sweden)

    Omar dos Santos Carvalho

    1976-10-01

    Full Text Available Junto ao Lago da Pampulha, Belo Horizonte, MG, foram capturados (julho/72-novembro/73 28 exemplares de Holochilus brasiliensis, dos quais 11 (39,3% eliminavam nas fezes ovos viáveis de S. mansoni. Miracídios da cepa mencionada ("H" infectaram Biomphalaria glabrata e as cercárias obtidas também infectaram camundongos albinos, recuperando-se, ao final do experimento, 35,3% de vermes adultos. Por outro lado, cercárias de cepa humana ("LE" de S. mansoni infectaram sete exemplares de H. brasiliensis, nascidos em laboratório, recuperando-se no fim de 60 dias, 30,5% de vermes adultos. Estudos anatomapatológicos de H. brasiliensis demonstraram infecção generalizada, encontrando-se granuloma no esôfago, estômago, intestino (delgado e grosso, fígado, baço, pâncreas e linfonodos abdominais. Espessamentos fibrosos da íntima da veia porta, granulomas em espaços porta e fibrose incipiente dos espaços porta e interlobular foram lesões decorrentes da presença de ovos de S. mansoni encontrados no fígado. Em ambiente semi-natural, foi possível fechar o ciclo do S. mansoni sem direta participação humana, utilizando-se B. glabrata experimentalmente infectadas com trematódeos da cepa "LE", H. brasiliensis nascidos em laboratório e B. glabrata nascida no ambiente semi-natural estabelecido. Verificou-se que ambas as cepas ("H" e "LE" comportaram-se de maneira análoga, não sendo verificadas, também, diferenças morfológicas entre os ovos e vermes adultos de ambas. As observações, realizadas no campo e no laboratório demonstraram que o Holochilus brasiliensis é bom hospedeiro de Schistosoma mansoni. Assim, em determinadas áreas e sob certas condições ecológicas, o cricetídeo em questão poderá, efetivamente, integrar-se ao ciclo do trematódeo na natureza, independente ou paralelamente à presença do homem. Assinala-se, finalmente, que o presente trabalho relata o segundo fechamento do ciclo biológico de S. mansoni em condi

  7. Revisão de Anyphaeninae Bertkau a nível de gêneros na Região Neotropical (Araneae, Anyphaenidae Revision of Anyphaeninae Bertkau at genera level in the Neotropical Region (Araneae, Anyphaenidae

    Directory of Open Access Journals (Sweden)

    Antonio Domingos Brescovit

    1996-12-01

    Teudis leucochlorus Mello-Leitão with Umuara fasciata (Blackwall; Aysha fulviceps Keyserling with Xiruana gracilipes (Keyserling; Aysha mandibularis (Keyserling with Aljassa subpallida (L. Koch. Seventy new combinations are presented: Wulfilopsis frenata (Keyserling; W. pygmaea (Keyserling; W. tenuipes (Keyserling; W. tripunctata (Mello-Leitão; Patrera apora (Chamberlin; P.armata (Chickering; P.auricoma (L. Koch; P. cita (Keyserling; P. lauta (Chickering; P. longipes (Keyserling; P. procera (Keyserling; P. puta (O.P.-Cambridge; P. ruber (F.O.P.-Cambridge; P. stylifer (F.O.P.-Cambridge; P. virgata (Keyserling; Teudis bicornutus (Tullgren; T. buelowae (Mello-Leitão; T. comstocki (Soares & Camargo; T. morenus (Mello-Leitão; Jessica campesina (Bauab-Vianna; J. glabra (Keyserling; J. goodnight (Soares & Camargo; J. osoriana (Mello-Leitão; J. erythrostoma (Mello- Leitão; J. rubricephala (Mello-Leitão; Iguarima censoria (Keyserling; Katissa delicatula (Banks; K. elegans (Banks; K. lycosoides (Chickering; K. simplicipalpis (Simon; K. zimarae (Reimoser; Otoniella quadrivittata (Simon; Lupettiana mordax (O.P.-Cambridge; L. parvula (Banks; L. perpusilla (Banks; L. spinosa (Bryant; Timbuka bogotensis (L. Koch; T. granadensis (Keyserling; T. larvata (O.P.-Cambridge, T. masseneti (Berland; T.meridiana (L. Koch; Tafana quelchii (pocock; T. silhavyi (Caporiacco; T. straminea (L. Koch; Umuara fascia J(Blackwall; Aysha basilisca (Mello-Leitâo; A. diversicolor (Keyserling; A. heraldica (Mello-Leitão; A. gentilis (Keyserling; A. helvola (Keyserling; A. robusta (Keyserling; A. rubro- maculata (Keyserling; A. striolata (Keyserling; A. subruba (Keyserling; Xiruana affinis (Mello-Leitão; X. gracilipes (Keyserling; X. hirsuta (Mello-Leitão; X. tetraseta (Mello-Leitão; Aljassa annulipes (Caporiacco; A. notata (Keyserling; A. poicila (Chamberlin; A. subpallida(L. Koch; A. venezuelica (Caporiacco; Pippuhana calcar (Bryant; H. donaldi (Chickering; P. unicolor (Keyserling; Hatitia

  8. Epidemiological studies of amphistome infections in cattle in the highveld and lowveld communal grazing areas of Zimbabwe

    Directory of Open Access Journals (Sweden)

    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

  9. 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

  10. Novel laboratory approaches to multi-purpose aquatic bioregenerative closed-loop food production systems.

    Science.gov (United States)

    Blum, V; Andriske, M; Kreuzberg, K; Paassen, U; Schreibman, M P; Voeste, D

    1998-01-01

    Based on the construction principle of the Closed Equilibrated Biological Aquatic System (C.E.B.A.S.) two novel combined animal-plant production systems were developed in laboratory scale the first of which is dedicated to mid-term operation in closed state up to two years. In principle both consist of the "classic" C.E.B.A.S. subcomponents: animal tank (Zoological Component), plant cultivators (Botanical Component), ammonia converting bacteria filter (Microbial Component) and data acquisition/control unit (Electronical Component). The innovative approach in the first system is the utilization of minimally three aquatic plant cultivators for different species. In this one the animal tank has a volume of about 160 liters and is constructed as an "endless-way system" surrounding a central unit containing the heat exchanger and the bacteria filter with volumes of about 1.5 liters each. A suspension plant cultivator (1 liter) for the edible duckweed Wolffia arrhiza is externally connected. The second plant cultivator is a meandric microalgal bioreactor for filamentous green algae. The third plant growth facility is a chamber with about 2.5 liters volume for cultivation of the "traditional" C.E.B.A.S. plant species, the rootless buoyant Ceratophyllum demersum. Both latter units are illuminated with 9 W fluorescent lamps. In the current experiment the animal tank contains the live-bearing teleost fish Xiphophorus helleri and the small pulmonate water snail Biomphalaria glabrata because their physiological adaptation to the closed system conditions is well known from many previous C.E.B.A.S. experiments. The water temperature is maintained at 25 degrees C and the oxygen level is regulated between 4 and 7 mg/l by switching on and off the plant cultivator illuminations according to a suitable pattern thus utilizing solely the oxygen produced by photosynthesis. The animals and the microorganisms of filter and biofilm provide the plants with a sufficient amount of carbon

  11. 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.

  12. Infecção natural de roedores silvestres pelo Schistosoma mansoni Natural infection of sylvatic rodents by Schistosoma mansoni

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    Tânia Maria Correa Silva

    1989-06-01

    Full Text Available No município baiano de Planalto, 47% dos roedores silvestres capturados (Nectomys estavam infectados pelo Schistosoma mansoni, enquanto a prevalência desta infecção na população humana da área era de 3,26%. Os roedores habitam zonas peridomiciliares, têm hábitos aquáticos e eliminam ovos viáveis do S. mansoni. Albergam número variável de vermes e formam granulomas periovulares pequenos, principalmente no fígado e intestinos, sem fibrose hepática importante ou sinais de hipertensão porta. A deposição maior de ovos se faz a nível do intestino, sobretudo do jejuno, com passagem de grande número de ovos para as fezes. Miracídios isolados a partir dos ovos retirados dos roedores infectaram normalmente a Biomphalaria glabrata, com eliminação de cercárias, com as quais se provocou infecção no camundongo branco, em tudo semelhante aquelas causadas por outras cepas de origem humana. Também camundongos que foram deixados em contacto com as águas infestadas pelos roedores silvestres se infectaram facilmente, atestando o alto grau de transmissibilidade da área. Conclui-se que os roedores silvestres de planalto toleram bem a infecção esquistossomótica natural, são bons eliminadores de ovos viáveis do S. mansoni, estão infectados por uma cepa semelhante a que infecta o homem e podem ter um papel na manutenção do ciclo vital do S. mansoni na área estudada.In Planalto, a small locality in the interior of the Bahia state, Brazil, 47% of sylvatic rodents were found to be naturally infected with Schistosoma mansoni, whereas the prevalence of the infection in the inhabitants of the area was 3.26%. The rodents (Nectomys live near the houses, in contact with water passing viable schistosome eggs in the stools. Worm burden is variable amongst such rodents. Periovular granulomas are small, especially in liver and intestines, and hepatic fibrosis is mild or absent, with no morphological evidence of portal hypertension being noted

  13. 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.

  14. Aquatic modules for bioregenerative life support systems based on the C.E.B.A.S. biotechnology

    Science.gov (United States)

    Bluem, Volker; Paris, Frank

    2001-03-01

    Most concepts for bioregenerative life support systems are based on edible higher land plants which create some problems with growth and seed generation under space conditions. Animal protein production is mostly neglected because of the tremendous waste management problems with tetrapods under reduced weightlessness. Therefore, the "Closed Equilibrated Biological Aquatic System" (C.E.B.A.S.) was developed which represents an artificial aquatic ecosystem containing aquatic organisms which are adpated at all to "near weightlessness conditions" (fishes Xiphophorus helleri, water snails Biomphalaria glabrata, ammonia oxidizing bacteria and the rootless non-gravitropic edible water plant Ceratophyllum demersum). Basically the C.E.B.A.S. consists of 4 subsystems: a ZOOLOGICASL COMPONENT (animal aquarium), a BOTANICAL COMPONENT (aquatic plant bioreactor), a MICROBIAL COMPONENT (bacteria filter) and an ELECTRONICAL COMPONENT (data acquisition and control unit). Superficially, the function principle appears simple: the plants convert light energy into chemical energy via photosynthesis thus producing biomass and oxygen. The animals and microorganisms use the oxygen for respiration and produce the carbon dioxide which is essential for plant photosynthesis. The ammonia ions excreted by the animals are converted by the bacteria to nitrite and then to nitrate ions which serve as a nitrogen source for the plants. Other essential ions derive from biological degradation of animal waste products and dead organic matter. The C.E.B.A.S. exists in 2 basic versions: the original C.E.B.A.S. with a volume of 150 liters and a self-sustaining standing time of more than 13 month and the so-called C.E.B.A.S. MINI MODULE with a volume of about 8.5 liters. In the latter there is no closed food loop by reasons of available space so that animal food has to be provided via an automated feeder. This device was flown already successfully on the STS-89 and STS-90 spaceshuttle missions and the