RESUMO
Schistosomiasis is a severely neglected disease with a wide geographical distribution. It affectsapproximately 210 million people in the world and at least 800 million people live in risk areas.The search for new drugs to treat this parasitosis is significant due to the appearance of strains of theworm that are resistant to the currently available drugs. The retrieval of compounds extracted fromplants that act on these parasites has increased scientific investigation of this subject. The presentstudy demonstrates, in vitro and in vivo, the action of crude extract of Piper tuberculatum on adultSchistosoma mansoni. The extract was shown to be quite effective in the in vitro tests, causing softtissue alterations and acting on the reproductive system of females and the mortality of the worms,with a greater effect on males. The in vivo experiment was performed with infected Mus musculusand a decrease in the number of eggs in the first and second oogram stages was found, suggestingaction on oviposition...
A esquistossomose, doença negligenciada grave e de larga distribuição geográfica, atinge cerca de210 milhões de pessoas no mundo e ao menos 800 milhões vivem em área de risco. A busca de novosmedicamentos para o tratamento desta parasitose é relevante em razão do aparecimento de linhagensdo verme resistentes aos fármacos disponíveis. A obtenção de compostos extraídos de plantas comação sobre parasitos tem incrementado a investigação científica sobre este assunto. O presentetrabalho mostra a ação in vitro e in vivo do extrato bruto de Piper tuberculatum sobre adultosde Schistosoma mansoni. O extrato mostrou-se bastante eficaz nos ensaios in vitro, provocandoalterações tegumentares, tendo ação no sistema reprodutor das fêmeas e na mortalidade dos vermes com maior ação sobre os machos. Como resultado em experimentos in vivo, realizados em Musmusculus infectados, observou-se a diminuição do número de ovos de 1º e 2º estágios em oogramas,o que sugere uma ação na postura de ovos...
Assuntos
Animais , Ratos , Animais de Laboratório , Esquistossomose mansoni/diagnóstico , Esquistossomose mansoni/epidemiologiaRESUMO
This study aimed to carry out malacological samples of limnic mollusks present in a commercial fishing pond area on Itapecerica da Serra, São Paulo/Brazil, between July 2006 to June 2007. Furthermore, parasitological studies were also performed on specimens found. A total of 19,863 limnic mollusks were collected, represented by six species: Biomphalaria straminea Dunker, 1848; Melanoides tuberculatus Müller, 1774; Lymnaea columella Say, 1817; Pomacea lineata Spix, 1827; Physa marmorata Guilding, 1828 and Anodontites trapesialis Lamarck, 1819, being this the first report of the occurrence of this species in fish and pay systems of Itapecerica da Serra. The parasitological examinations performed in 5,766 mollusks were negative, however, the greatest abundance of B. straminea, intermediate host of Schistosoma mansoni Sambon, 1907, becomes a concern. Thus, the need for increasing the malacological surveillance in the region due to the diversity of hydric collections in the municipality that has precarious sanitation conditions, high migration flow and the presence of imported and autochthonous cases of schistosomiasis.
Este trabalho teve como objetivo realizar levantamento da malacofauna límnica encontrada na área de um pesqueiro em Itapecerica da Serra, São Paulo - Brasil, no período de julho de 2006 a junho de 2007. Como complementação, foram feitos estudos parasitológicos em parte dos moluscos amostrados. Foram coletados 19.863 moluscos límnicos, representados por seis espécies: Biomphalaria straminea Dunker, 1848; Melanoides tuberculatus Müller, 1774; Lymnaea columella Say, 1817; Pomacea lineata Spix, 1827; Physa marmorata Guilding, 1828 e Anodontites trapesialis Lamarck, 1819. Este pode ser considerado o primeiro relato da ocorrência dessas espécies em pesqueiros de Itapecerica da Serra. Os exames parasitológicos realizados em 5.766 moluscos foram negativos, no entanto, a presença de B. straminea, hospedeiro intermediário do Schistosoma mansoni Sambon, 1907 é preocupante. Diante disso, é necessário intensificar a vigilância malacológica na região devido à diversidade de coleções hídricas do município, precárias condições de saneamento básico, alto fluxo migratório de pessoas e o relato de casos importados e autóctones de esquistossomose.
RESUMO
This study aimed to carry out malacological samples of limnic mollusks present in a commercial fishing pond area on Itapecerica da Serra, São Paulo/Brazil, between July 2006 to June 2007. Furthermore, parasitological studies were also performed on specimens found. A total of 19,863 limnic mollusks were collected, represented by six species: Biomphalaria straminea Dunker, 1848; Melanoides tuberculatus Müller, 1774; Lymnaea columella Say, 1817; Pomacea lineata Spix, 1827; Physa marmorata Guilding, 1828 and Anodontites trapesialis Lamarck, 1819, being this the first report of the occurrence of this species in fish and pay systems of Itapecerica da Serra. The parasitological examinations performed in 5,766 mollusks were negative, however, the greatest abundance of B. straminea, intermediate host of Schistosoma mansoni Sambon, 1907, becomes a concern. Thus, the need for increasing the malacological surveillance in the region due to the diversity of hydric collections in the municipality that has precarious sanitation conditions, high migration flow and the presence of imported and autochthonous cases of schistosomiasis.
Este trabalho teve como objetivo realizar levantamento da malacofauna límnica encontrada na área de um pesqueiro em Itapecerica da Serra, São Paulo - Brasil, no período de julho de 2006 a junho de 2007. Como complementação, foram feitos estudos parasitológicos em parte dos moluscos amostrados. Foram coletados 19.863 moluscos límnicos, representados por seis espécies: Biomphalaria straminea Dunker, 1848; Melanoides tuberculatus Müller, 1774; Lymnaea columella Say, 1817; Pomacea lineata Spix, 1827; Physa marmorata Guilding, 1828 e Anodontites trapesialis Lamarck, 1819. Este pode ser considerado o primeiro relato da ocorrência dessas espécies em pesqueiros de Itapecerica da Serra. Os exames parasitológicos realizados em 5.766 moluscos foram negativos, no entanto, a presença de B. straminea, hospedeiro intermediário do Schistosoma mansoni Sambon, 1907 é preocupante. Diante disso, é necessário intensificar a vigilância malacológica na região devido à diversidade de coleções hídricas do município, precárias condições de saneamento básico, alto fluxo migratório de pessoas e o relato de casos importados e autóctones de esquistossomose.
Assuntos
Animais , Doenças Transmissíveis , Pesqueiros , Helmintos , Moluscos/parasitologiaRESUMO
Schistosomiasis is a neglected tropical disease that remains a considerable public health problem worldwide. Since the mainstay of schistosomiasis control is chemotherapy with a single drug,praziquantel, drug resistance is a concern. Here, we examined the in vitro effects of dermaseptin 01(DS 01), an antimicrobial peptide found in the skin secretion of frogs of the genus Phyllomedusa, onSchistosoma mansoni adult worms. DS 01 at a concentration of 100 mg/ml reduced the worm motor activity and caused the death of all worms within 48 h in RPMI 1640 medium. At the highest sublethal concentration of antimicrobial peptide (75 mg/ml), a 100% reduction in egg output of paired female worms was observed. Additionally, DS 01 induced morphological alterations on the tegument of S. mansoni, and a quantitative analysis carried out by confocal microscopy revealed extensive destruction of the tubercles in a dose-dependent manner over the concentration range of 50 200 mg/ml. It was the first time that an anthelmintic activity towards schistosomes has been reported for a dermaseptin.
Assuntos
Peptídeos Catiônicos Antimicrobianos/administração & dosagem , Peptídeos Catiônicos Antimicrobianos/análise , Schistosoma mansoni , Schistosoma mansoni/parasitologia , Genoma Helmíntico , Microscopia Confocal/métodos , Tegumento Comum/anormalidadesRESUMO
Schistosomiasis is a neglected tropical disease that remains a considerable public health problem worldwide. Since the mainstay of schistosomiasis control is chemotherapy with a single drug, praziquantel, drug resistance is a concern. Here, we examined the in vitro effects of dermaseptin 01 (DS 01), an antimicrobial peptide found in the skin secretion of frogs of the genus Phyllomedusa, on Schistosoma mansoni adult worms. DS 01 at a concentration of 100 µg/ml reduced the worm motor activity and caused the death of all worms within 48 h in RPMI 1640 medium. At the highest sublethal concentration of antimicrobial peptide (75 µg/ml), a 100% reduction in egg output of paired female worms was observed. Additionally, DS 01 induced morphological alterations on the tegument of S. mansoni, and a quantitative analysis carried out by confocal microscopy revealed extensive destruction of the tubercles in a dose-dependent manner over the concentration range of 50-200 µg/ml. It was the first time that an anthelmintic activity towards schistosomes has been reported for a dermaseptin.
Assuntos
Proteínas de Anfíbios/farmacologia , Anti-Helmínticos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Proteínas de Anfíbios/química , Proteínas de Anfíbios/isolamento & purificação , Animais , Anti-Helmínticos/química , Anti-Helmínticos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Anuros , Relação Dose-Resposta a Droga , Feminino , Óvulo/efeitos dos fármacos , Schistosoma mansoni/fisiologia , Pele/química , Especificidade da EspécieRESUMO
Schistosomiasis is one of the world's greatly neglected tropical diseases, and its control is largely dependent on a single drug, praziquantel. Here, we report the in vitro effect of piplartine, an amide isolated from Piper tuberculatum (Piperaceae), on Schistosoma mansoni adult worms. A piplartine concentration of 15.8 µM reduced the motor activity of worms and caused their death within 24h in a RPMI 1640 medium. Similarly, the highest sub-lethal concentration of piplartine (6.3 µM) caused a 75% reduction in egg production in spite of coupling. Additionally, piplartine induced morphological changes on the tegument, and a quantitative analysis carried out by confocal microscopy revealed an extensive tegumental destruction and damage in the tubercles. This damage was dose-dependent in the range of 15.8-630.2 µM. At doses higher than 157.6 µM, piplartine induced morphological changes in the oral and ventral sucker regions of the worms. It is the first time that the schistosomicidal activity has been reported for piplartine.
Assuntos
Piperidonas/farmacologia , Extratos Vegetais/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Animais , Biomphalaria , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Cricetinae , Feminino , Masculino , Mesocricetus , Microscopia Confocal , Piper/química , Piperidonas/isolamento & purificação , Piperidonas/toxicidade , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Células VeroRESUMO
Schistosomiasis affects more than 200 million people worldwide; another 600 million are at risk of infection. The schistosomulum stage is believed to be the target of protective immunity in the attenuated cercaria vaccine model. In an attempt to identify genes up-regulated in the schistosomulum stage in relation to cercaria, we explored the Schistosoma mansoni transcriptome by looking at the relative frequency of reads in EST libraries from both stages. The 400 genes potentially up-regulated in schistosomula were analyzed as to their Gene Ontology categorization, and we have focused on those encoding-predicted proteins with no similarity to proteins of other organisms, assuming they could be parasite-specific proteins important for survival in the host. Up-regulation in schistosomulum relative to cercaria was validated with real-time reverse transcription polymerase chain reaction (RT-PCR) for five out of nine selected genes (56%). We tested their protective potential in mice through immunization with DNA vaccines followed by a parasite challenge. Worm burden reductions of 16-17% were observed for one of them, indicating its protective potential. Our results demonstrate the value and caveats of using stage-associated frequency of ESTs as an indication of differential expression coupled to DNA vaccine screening in the identification of novel proteins to be further investigated as potential vaccine candidates.
Assuntos
Perfilação da Expressão Gênica , Schistosoma mansoni/crescimento & desenvolvimento , Schistosoma mansoni/genética , Animais , Antígenos de Helmintos/biossíntese , DNA de Helmintos/química , DNA de Helmintos/genética , Etiquetas de Sequências Expressas , Proteínas de Helminto/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esquistossomose mansoni/prevenção & controle , Análise de Sequência de DNA , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologiaRESUMO
Developing a vaccine against schistosomiasis would be an important advance on the control of this chronic and debilitating disease that afflicts millions of people worldwide. Herein we describe the use of the non-toxic B subunit of cholera toxin (CTB) genetically fused to Sm14 - a fatty-acid binding protein from Schistosoma mansoni - as an attempt to elicit a mucosal immune response against the lung stage of this parasite by intranasal immunization. Recombinant proteins were expressed on a prokaryotic system, purified by affinity chromatography and both immunochemically and spectroscopically characterized. Intranasal immunization experiments were performed on BALB/c mice and vaccine efficacy was assessed analyzing the worm-burden after challenge infection with S. mansoni cercariae. The results demonstrate that Sm14 itself was not able to reduce the worm burden on intranasally vaccinated animals. The presence of CTB either in intranasal coadministration with or genetically fused to Sm14 did not significantly improve the protective response of Sm14 as a worm burden reduction of only 20% could be observed. In addition to that, however, CTB demonstrated a clear anti inflammatory effect on the liver of immunized mice, which displayed hepatic granulomas around trapped eggs 15% smaller than control groups, indicating that CTB displays an immunomodulatory effect on the inflammatory responses induced by the parasite egg toxins.
Assuntos
Humanos , Esquistossomose/imunologia , VacinasRESUMO
Schistosomiasis is one of the worlds greatly neglected tropical diseases, and its control is largely dependenton a single drug, praziquantel. Here, we report the in vitro effect of piplartine, an amide isolated from Piper tuberculatum (Piperaceae), on Schistosoma mansoni adult worms. A piplartine concentrationof 15.8 lM reduced the motor activity of worms and caused their death within 24 h in a RPMI 1640 medium.Similarly, the highest sub-lethal concentration of piplartine (6.3 lM) caused a 75% reduction in eggproduction in spite of coupling. Additionally, piplartine induced morphological changes on the tegument,and a quantitative analysis carried out by confocal microscopy revealed an extensive tegumental destructionand damage in the tubercles. This damage was dose-dependent in the range of 15.8630.2 lM. At doses higher than 157.6 lM, piplartine induced morphological changes in the oral and ventral sucker regions of the worms. It is the first time that the schistosomicidal activity has been reported forpiplartine.
Assuntos
Piper/parasitologia , Piper/toxicidade , Schistosoma mansoni/parasitologia , Esquistossomicidas/administração & dosagem , Esquistossomicidas/análise , Esquistossomicidas/uso terapêuticoRESUMO
Schistosomiasis affects more than 200 million people worldwide; another 600 million are at risk ofinfection. The schistosomulum stage is believed to be the target of protective immunity in the attenuated cercaria vaccine model. In an attempt to identify genes upregulated in the schistosomulum stage in relation to cercaria, we explored the Schistosoma mansoni transcriptome by looking at the relative frequency of reads in EST libraries from both stages. The 400 genes potentially up-regulated in schistosomula were analyzed as to their Gene Ontology categorization, and we have focused on those encoding-predicted proteins with no similarity to proteins of other organisms, assuming they could be parasite-specific proteins important for survival in the host. Up-regulation in schistosomulum relative to cercaria was validated with real-time reverse transcription polymerase chain reaction (RT-PCR) for five out of nine selected genes (56%). We tested their protective potential in mice through immunization with DNA vaccines followed by a parasite challenge. Worm burden reductions of 1617% were observed for one of them, indicating its protective potential. Our results demonstrate the value and caveats of using stage-associated frequency of ESTs as na indication of differential expression coupled to DNA vaccine screening in the identification of novel proteins to be further investigated as potential vaccine candidates.
Assuntos
Camundongos , Imunização , Produção de Produtos , Schistosoma mansoni/imunologia , Cercárias/imunologia , Transcriptoma/fisiologiaRESUMO
To observe the effects of the parasitic infection on the biology of B. tenagophila, field and laboratory populations of this mollusk from Itariri, in Vale do Ribeira, Brazil, were experimentally infected. Each mollusk received 10 miracidia of Schistosoma mansoni (SJ lineage) and was observed throughout the parasite's development. The biological variables were compared according to the criteria "group" and "infectious phase". The main damage caused by the parasitic infection manifested itself in reproduction, longevity and lesions on the shell of the mollusks in the patent phase. An infection rate of 58.8% was observed. Microanatomical study of the mollusk's digestive gland and ovotestis revealed the presence of evolving larval forms and cercariae. It was concluded that the effects of the parasitic infection on both populations were moderate, despite the low survival rate of the infected mollusks, the damage did not prevent either reproduction or the elimination of cercariae, which continued for a long time.
Assuntos
Biomphalaria/parasitologia , Schistosoma mansoni/fisiologia , Animais , Brasil , Feminino , Fertilidade , Interações Hospedeiro-Parasita , Masculino , Análise de SobrevidaRESUMO
To observe the effects of the parasitic infection on the biology of B. tenagophila, field and laboratory populations of this mollusk from Itariri, in Vale do Ribeira, Brazil, were experimentally infected. Each mollusk received 10 miracidia of Schistosoma mansoni (SJ lineage) and was observed throughout the parasite's development. The biological variables were compared according to the criteria "group" and "infectious phase". The main damage caused by the parasitic infection manifested itself in reproduction, longevity and lesions on the shell of the mollusks in the patent phase. An infection rate of 58.8 percent was observed. Microanatomical study of the mollusk's digestive gland and ovotestis revealed the presence of evolving larval forms and cercariae. It was concluded that the effects of the parasitic infection on both populations were moderate, despite the low survival rate of the infected mollusks, the damage did not prevent either reproduction or the elimination of cercariae, which continued for a long time.
Com objetivo de observar os efeitos da infecção parasitária na biologia de B. tenagophila, foram realizadas infecções experimentais em populações de campo e laboratório, ambas procedentes de Itariri, Vale do Ribeira, Brasil. Cada molusco recebeu 10 miracídios de Schistosoma mansoni (linhagem SJ), sendo observado durante o desenvolvimento dos parasitos. As variáveis biológicas foram comparadas segundo os critérios "grupo" e "fase de infecção". Os principais danos decorrentes do parasitismo se manifestaram na reprodução, na longevidade e em lesões na concha dos moluscos na fase patente. Foi encontrada uma taxa de infecção de 58,8 por cento. O estudo microanatômico da glândula digestiva e do ovoteste do molusco revelou a presença de formas larvárias em evolução e cercárias. Concluiu-se que os efeitos da infecção parasitária, sobre as duas populações, foram moderados, uma vez que os danos não impediram a reprodução e a eliminação de cercárias que se manteve por um longo período, apesar da baixa sobrevivência dos moluscos parasitados.
Assuntos
Animais , Feminino , Masculino , Biomphalaria/parasitologia , Schistosoma mansoni/fisiologia , Brasil , Fertilidade , Interações Hospedeiro-Parasita , Análise de SobrevidaRESUMO
BACKGROUND: Schistosomiasis affects more than 200 million individuals worldwide, with a further 650 million living at risk of infection, constituting a severe health problem in developing countries. Even though an effective treatment exists, it does not prevent re-infection, and the development of an effective vaccine still remains the most desirable means of control for this disease. METHODOLOGY/PRINCIPAL FINDINGS: Herein, we report the cloning and characterization of a S. mansoni Stomatin-like protein 2 (SmStoLP-2). In silico analysis predicts three putative sites for palmitoylation (Cys11, Cys61 and Cys330), which could contribute to protein membrane association; and a putative mitochondrial targeting sequence, similar to that described for human Stomatin-like protein 2 (HuSLP-2). The protein was detected by Western blot with comparable levels in all stages across the parasite life cycle. Fractionation by differential centrifugation of schistosome tegument suggested that SmStoLP-2 displays a dual targeting to the tegument membranes and mitochondria; additionally, immunolocalization experiments confirm its localization in the tegument of the adult worms and, more importantly, in 7-day-old schistosomula. Analysis of the antibody isotype profile to rSmStoLP-2 in the sera of patients living in endemic areas for schistosomiasis revealed that IgG1, IgG2, IgG3 and IgA antibodies were predominant in sera of individuals resistant to reinfection as compared to those susceptible. Next, immunization of mice with rSmStoLP-2 engendered a 30%-32% reduction in adult worm burden. Protective immunity in mice was associated with specific anti-rSmStoLP-2 IgG1 and IgG2a antibodies and elevated production of IFN-gamma and TNF-alpha, while no IL-4 production was detected, suggesting a Th1-predominant immune response. CONCLUSIONS/SIGNIFICANCE: Data presented here demonstrate that SmStoLP-2 is a novel tegument protein located in the host-parasite interface. It is recognized by different subclasses of antibodies in patients resistant and susceptible to reinfection and, based on the data from murine studies, shows protective potential against schistosomiasis. These results indicate that SmStoLP-2 could be useful in a combination vaccine.
Assuntos
Antígenos de Helmintos/análise , Antígenos de Helmintos/imunologia , Proteínas de Helminto/análise , Proteínas de Helminto/imunologia , Schistosoma mansoni/química , Schistosoma mansoni/imunologia , Esquistossomose mansoni/prevenção & controle , Animais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/genética , Clonagem Molecular , Feminino , Proteínas de Helminto/genética , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Interferon gama/metabolismo , Leucócitos Mononucleares/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Organelas/química , Esquistossomose mansoni/imunologia , Análise de Sequência de DNA , Fator de Necrose Tumoral alfa/metabolismo , VacinaçãoRESUMO
BACKGROUND: Schistosoma mansoni is the major causative agent of schistosomiasis. The parasite takes advantage of host signals to complete its development in the human body. Tumor necrosis factor-alpha (TNF-alpha) is a human cytokine involved in skin inflammatory responses, and although its effect on the adult parasite's metabolism and egg-laying process has been previously described, a comprehensive assessment of the TNF-alpha pathway and its downstream molecular effects is lacking. METHODOLOGY/PRINCIPAL FINDINGS: In the present work we describe a possible TNF-alpha receptor (TNFR) homolog gene in S. mansoni (SmTNFR). SmTNFR encodes a complete receptor sequence composed of 599 amino acids, and contains four cysteine-rich domains as described for TNFR members. Real-time RT-PCR experiments revealed that SmTNFR highest expression level is in cercariae, 3.5 (+/-0.7) times higher than in adult worms. Downstream members of the known human TNF-alpha pathway were identified by an in silico analysis, revealing a possible TNF-alpha signaling pathway in the parasite. In order to simulate parasite's exposure to human cytokine during penetration of the skin, schistosomula were exposed to human TNF-alpha just 3 h after cercariae-to-schistosomula in vitro transformation, and large-scale gene expression measurements were performed with microarrays. A total of 548 genes with significantly altered expression were detected, when compared to control parasites. In addition, treatment of adult worms with TNF-alpha caused a significantly altered expression of 1857 genes. Interestingly, the set of genes altered in adults is different from that of schistosomula, with 58 genes in common, representing 3% of altered genes in adults and 11% in 3 h-old early schistosomula. CONCLUSIONS/SIGNIFICANCE: We describe the possible molecular elements and targets involved in human TNF-alpha effect on S. mansoni, highlighting the mechanism by which recently transformed schistosomula may sense and respond to this host mediator at the site of cercarial penetration into the skin.
Assuntos
Regulação da Expressão Gênica , Proteínas de Helminto/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Schistosoma mansoni/genética , Esquistossomose mansoni/imunologia , Fator de Necrose Tumoral alfa/imunologia , Sequência de Aminoácidos , Animais , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Helminto/química , Proteínas de Helminto/metabolismo , Humanos , Dados de Sequência Molecular , Filogenia , Receptores Tipo I de Fatores de Necrose Tumoral/química , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Schistosoma mansoni/química , Schistosoma mansoni/classificação , Schistosoma mansoni/metabolismo , Esquistossomose mansoni/parasitologia , Alinhamento de Sequência , Transdução de Sinais , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
A total of 909 Biomphalaria tenagophila were collected from two areas in Guarulhos (Metropolitan area of São Paulo, São Paulo State, Brazil) to assess larval trematode infections. In all collection sites, only this species was found and 183 (20.13%) harbored trematode infections. In these collections, four morphologically distinguishable types of cercariae were identified by confocal microscopy. Xiphidiocercaria (Cercaria lutzi) was the most common type of cercaria recovered, contributing 76.5% of all infections. Schistosoma mansoni cercariae were recovered and comprised the total of 13.11%. Strigea cercaria (Cercaria caratinguensis) and Brevifurcate pharyngeate Clinostomatoide cercaria (Cercaria ocellifera) contributed 8.33% and 2.22% of all infections, respectively. Double infections (S. mansoni and C. lutzi) were found in twelve snails, contributing 6.55% of all infections. In all sites studied, small vertebrates were found in snail habitats and it was observed human contact with the water. The presence of trematode infected snails in large cities has public health implications. It further provides a starting point for some comprehensive studies on snail-related aspects of transmission and biology of trematode of medical and veterinary importance.
Assuntos
Biomphalaria/parasitologia , Schistosoma mansoni/isolamento & purificação , Trematódeos/isolamento & purificação , Animais , Brasil , Larva/classificação , Trematódeos/classificaçãoRESUMO
A total of 909 Biomphalaria tenagophila were collected from two areas in Guarulhos (Metropolitan area of São Paulo, São Paulo State, Brazil) to assess larval trematode infections. In all collection sites, only this species was found and 183 (20.13%) harbored trematode infections. In these collections, four morphologically distinguishable types of cercariae were identified by confocal microscopy. Xiphidiocercaria (Cercaria lutzi) was the most common type of cercaria recovered, contributing 76.5% of all infections. Schistosoma mansoni cercariae were recovered and comprised the total of 13.11%. Strigea cercaria (Cercaria caratinguensis) and Brevifurcate pharyngeate Clinostomatoide cercaria (Cercaria ocellifera) contributed 8.33% and 2.22% of all infections, respectively. Double infections (S. mansoni and C. lutzi) were found in twelve snails, contributing 6.55% of all infections. In all sites studied, small vertebrates were found in snail habitats and it was observed human contact with the water. The presence of trematode infected snails in large cities has public health implications. It further provides a starting point for some comprehensive studies on snail-related aspects of transmission and biology of trematode of medical and veterinary importance.
Um total de 909 exemplares de Biomphalaria tenagophila foi coletado de duas regiões em Guarulhos (área Metropolitana de São Paulo, Estado de São Paulo, Brasil) a fim de que fosse verificada infecção por larvas de trematódeos. Em todos os locais de coleta, somente essa espécie foi encontrada e 183 (20,13%) caramujos estavam infectados. Nestes locais, quatro tipos de cercárias foram identificadas com microscópio confocal. Xiphidiocercaria (Cercaria luzti) foi o tipo de cercária mais comum, contribuindo com 76,5% de toda infecção. Cercárias de Schistosoma mansoni foram encontradas, obtendo um total de 13,11%. Strigea cercaria (Cercaria caratinguensis) e Brevifurcate pharyngeate Clinostomatoide cercaria (Cercaria ocellifera) contribuíram com 8,33% e 2,22% de toda infecção, respectivamente. Dupla infecção foi encontrada em doze caramujos, contribuindo com 6,55% de toda infecção. Em todos os locais, pequenos vertebrados foram encontrados e foi observado contato humano com a água. A presença de caramujos infectados por trematódeos que infectam o homem em grandes cidades tem implicações na saúde pública. Deve-se salientar a importância de mais estudos epidemiológicos e biológicos destes parasitas de importância médica e veterinária.
Assuntos
Animais , Biomphalaria/parasitologia , Schistosoma mansoni/isolamento & purificação , Trematódeos/isolamento & purificação , Brasil , Larva/classificação , Trematódeos/classificaçãoRESUMO
The single cell gel electrophoresis or the comet assay was established in the freshwater snail Biomphalaria glabrata. For detecting DNA damage in circulating hemocytes, adult snails were irradiated with single doses of 2.5, 5, 10 and 20 Gy of (60)Co gamma radiation. Genotoxic effect of ionizing radiation was detected at all doses as a dose-related increase in DNA migration. Comet assay in B. glabrata demonstrated to be a simple, fast and reliable tool in the evaluation of genotoxic effects of environmental mutagens.
Assuntos
Bioensaio/métodos , Biomphalaria , Dano ao DNA , Monitoramento Ambiental/métodos , Animais , Biomphalaria/genética , Biomphalaria/efeitos da radiação , Ensaio Cometa , Relação Dose-Resposta à Radiação , Raios gama , Hemolinfa/efeitos da radiação , Sensibilidade e EspecificidadeRESUMO
Dominant lethal effects of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) were evaluated in the freshwater snail Biomphalaria glabrata. Wild-type snails were exposed during 10 days to 50, 75 and 100ppm of 2,4-D dimethylamine salt (2,4-D DMA) and paired with non-exposed albino snails 1, 11, 25 and 40 days after the exposure. The offspring of the non-exposed albino snails was scored for lethal malformations. One day after the exposure, a significant effect was observed at 75 and 100ppm without a dose-response relationship. After 11 days, the effect was observed only at the highest dose. After 25 days, significant increases in the dominant lethal effects occurred at 50 and 75ppm; effects were directly related to the doses. Background levels of lethal malformations were resumed after 40 days. Although the major and direct measure of dominant lethal mutations is the rate of lethal malformations in the heterozygous offspring of the albino snails, the sensitivity of the assay was substantially increased with the evaluation of all non-viable embryos, that are the sum of those with lethal malformations, identified or not as wild-type.
Assuntos
Ácido 2,4-Diclorofenoxiacético/toxicidade , Biomphalaria/efeitos dos fármacos , Animais , Biomphalaria/embriologia , Biomphalaria/genética , Relação Dose-Resposta a Droga , Embrião não Mamífero/anormalidades , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Feminino , Genes Dominantes/genética , Genes Letais/genética , Células Germinativas/efeitos dos fármacos , Células Germinativas/metabolismo , Células Germinativas/patologia , Herbicidas/toxicidade , Masculino , Testes de Mutagenicidade/métodos , Mutagênicos/toxicidade , Fatores de TempoRESUMO
Aqueous and alcoholic extracts were obtained from crushed dried leaves of tomato plant (Lycopersicon esculentum, Mill.) c.v. Cherry. By the use of a methanolic extraction and alkaline precipitation, a product named crude steroidal glycoalkaloid (GEb), was obtained. The presence of tomatidine was characterized in this product. In laboratory, the aqueous and alcoholic extracts and GEb have shown molluscicidal activity against Biomphalaria glabrata (Say, 1818). The crude steroidal glycoalkaloid presented a high molluscicidal activity (LC50 = 8.01 ppm and LC90 = 13.17 ppm), similar to that of tomatine. None of the compounds tested affected B. glabrata egg masses. The level of activity showed by the different extracts and by the GEb, pointed out the GEb as the only candidate able to be considered for further tests toward field trials as molluscicidal agent.
Foram obtidos extratos aquosos e alcoólicos a partir de pó de folhas secas de tomateiro (Lycopersicon esculentum, Mill.) c.v. Cereja. Por extração metanólica e precipitação alcalina, foi obtido um produto que denominamos "glicoalcalóide esteroidal bruto" (GEb), no qual foi caracterizada a presença de tomatina. Em ensaios laboratoriais, os extratos aquosos, alcoólicos e o GEb apresentaram atividade moluscicida em Biomphalaria glabrata (Say, 1818). O "glicoalcalóide esteroidal bruto" apresentou alta atividade moluscicida (CL50 = 8,01 ppm e CL90 = 13,17 ppm), comparável à atividade da tomatina. Desovas de B. glabrata mostraram-se resistentes aos extratos testados. Os níveis de atividade moluscicida apresentados pelos diversos extratos e o GEb, apontam apenas o GEb como candidato para a continuação dos estudos visando a sua possível utilização em campo.
RESUMO
Aqueous and alcoholic extracts were obtained from crushed dried leaves of tomato plant (Lycopersicon esculentum, Mill.) c.v. Cherry. By the use of a methanolic extraction and alkaline precipitation, a product named crude steroidal glycoalkaloid (GEb), was obtained. The presence of tomatidine was characterized in this product. In laboratory, the aqueous and alcoholic extracts and GEb have shown molluscicidal activity against Biomphalaria glabrata (Say, 1818). The crude steroidal glycoalkaloid presented a high molluscicidal activity (LC50 = 8.01 ppm and LC90 = 13.17 ppm), similar to that of tomatine. None of the compounds tested affected B. glabrata egg masses. The level of activity showed by the different extracts and by the GEb, pointed out the GEb as the only candidate able to be considered for further tests toward field trials as molluscicidal agent.
Foram obtidos extratos aquosos e alcoólicos a partir de pó de folhas secas de tomateiro (Lycopersicon esculentum, Mill.) c.v. Cereja. Por extração metanólica e precipitação alcalina, foi obtido um produto que denominamos "glicoalcalóide esteroidal bruto" (GEb), no qual foi caracterizada a presença de tomatina. Em ensaios laboratoriais, os extratos aquosos, alcoólicos e o GEb apresentaram atividade moluscicida em Biomphalaria glabrata (Say, 1818). O "glicoalcalóide esteroidal bruto" apresentou alta atividade moluscicida (CL50 = 8,01 ppm e CL90 = 13,17 ppm), comparável à atividade da tomatina. Desovas de B. glabrata mostraram-se resistentes aos extratos testados. Os níveis de atividade moluscicida apresentados pelos diversos extratos e o GEb, apontam apenas o GEb como candidato para a continuação dos estudos visando a sua possível utilização em campo.