scholarly journals Evaluation of the In Vivo Activity of Tribendimidine against Schistosoma mansoni, Fasciola hepatica, Clonorchis sinensis, and Opisthorchis viverrini

2006 ◽  
Vol 51 (3) ◽  
pp. 1096-1098 ◽  
Author(s):  
Jennifer Keiser ◽  
Xiao Shu-Hua ◽  
Jacques Chollet ◽  
Marcel Tanner ◽  
Jürg Utzinger
Keyword(s):  
Schistosoma Mansoni ◽  
Fasciola Hepatica ◽  
Clonorchis Sinensis ◽  
Opisthorchis Viverrini ◽  
High Doses

ABSTRACT We examined the in vivo activity of tribendimidine against selected trematodes. A single 150-mg/kg dose of tribendimidine achieved a 99.1% reduction of Clonorchis sinensis in rats. A 400-mg/kg dose of tribendimidine reduced Opisthorchis viverrini in hamsters by 95.7%. High doses of tribendimidine showed no activity against Schistosoma mansoni and Fasciola hepatica.

scholarly journals Helminth infection-induced carcinogenesis: spectrometric insights from the liver flukes, Opisthorchis and Fasciola

2019 ◽  
Author(s):  
Maria João Gouveia ◽  
Maria Y. Pakharukova ◽  
Banchob Sripa ◽  
Gabriel Rinaldi ◽  
Paul J. Brindley ◽  
...  
Keyword(s):  
Dna Adducts ◽  
Liver Fluke ◽  
Helminth Infection ◽  
Fasciola Hepatica ◽  
Clonorchis Sinensis ◽  
Opisthorchis Viverrini ◽  
International Agency ◽  
Fresh Water Fish ◽  
Liver Flukes ◽  
Group 1

AbstractChronic infections with the flatworm parasites Opisthorchis viverrini, Clonorchis sinensis and Schistosoma haematobium are classified as group 1 biological carcinogens, i.e. definitive causes of cancer. In addition, we reported findings that support the inclusion of Opisthorchis felineus in this list of biological carcinogens. By contrast, infections with close phylogenetic relatives including Fasciola hepatica have not been associated with carcinogenesis. Earlier reports revealed of oxysterol metabolites of Opisthorchis liver fluke origin conjugated with DNA bases, suggesting that the generation of these DNA-adducts may underlie the mutagenicity and carcinogenicity of the infection with these food-borne pathogens. Here we employed liquid chromatography-mass spectrometry (LC-MS/MS) to investigate, compare and contrast spectrograms of soluble extracts from F. hepatica adult worms from bile ducts of cattle with those from O. viverrini and O. felineus from experimentally-infected hamsters. F. hepatica displayed a complex spectrophotometric profile. F. hepatica and Opisthorchis spp. shared several common compounds including oxysterol-like metabolites, bile acids and DNA-adducts, but the spectrometric profiles of these Opisthorchis species included far fewer compounds than F. hepatica. These findings support the postulate that oxysterol-like metabolites of parasite origin can initiate carcinogenesis and they point to a molecular basis for the inconsistencies among major groups of liver flukes concerning infection-induced malignancy.Author SummarySeveral species of trematodes are parasites of the human hepatobiliary tract. Infection with two of these flukes, Clonorchis sinsensis and Opisthorchis viverrini, fresh water fish-borne parasites that occur in East Asia is classified as group 1 carcinogens by the International Agency for Research on Cancer (IARC), i.e. definitive causes of cancer in humans. By contrast, infection with a different liver fluke, Fasciola hepatica, does not lead to malignant transformation of the biliary tract. Given the close phylogeny of all three parasites, this difference in carcinogenicity is intriguing and, if explained, likely of value in novel therapeutic approaches. The importance of the current findings is informative because they present a mass spectrometric analysis and catalog of the similarities and differences between fluke of the genus Opisthorchis and F. hepatica, potentially identifying carcinogenic metabolites of liver fluke origin. These metabolites can be expected to provide deeper understanding of helminth infection induced malignancy.

Studies on the excystment of trematode metacercariae in vivo

1974 ◽  
Vol 48 (1) ◽  
pp. 85-91 ◽  
Author(s):  
M. F. A. Asanji ◽  
M. O. Williams
Keyword(s):  
Small Intestine ◽  
Definitive Host ◽  
Fasciola Hepatica ◽  
Clonorchis Sinensis ◽  
Body Cavity ◽  
The Body ◽  
Parorchis Acanthus ◽  
Migratory Route ◽  
Ph Range

AbstractMetacercariae of two species of trematode (Clinostomum tilapiae, Postodiplostomum nanum) excysted in the stomach of birds, while those of three species (Parorchis acanthus, Posthodiplostomum sp., Postliodiplostomoides leonensis) excysted in the duodenum. Differences were related to the structure of the cyst wall. All could excyst in birds which were not the definitive host and the speed of excystment depended on the speed of movement of food in the gut. All, except P. acanthus, also excysted in the body cavity of the mouse.There have been few previous reports on the site of excystment of metacercarial cysts in vivo and most indicate that the duodenum is the site for most species studied, e.g. Clonorchis sinensis (Faust and Khaw, 1927), Parorchis avitus (Stunkard and Cable, 1932), Cryptocotyle lingua (Smyth, 1962) and Fasciola hepatica (Smyth, 1966). In their study of the migratory route of Paragonimus westermani in rats, cats and guinea-pigs Yokogawa et al. (1962) found that excystment occurred in the small intestine where the pH range was 5.0–6.0. Also, although the site of excystment has been established for some species, very little quantitative work has been reported about the percentage excystment in vivo and results of work on these lines is reported in this paper.

Passive immunization of mice against Schistosoma mansoni with an IgM monoclonal antibody

Parasitology ◽  
1982 ◽  
Vol 84 (1) ◽  
pp. 83-91 ◽  
Author(s):  
M. A. Smith ◽  
J. A. Clegg ◽  
D. Snary ◽  
A. J. Trejdosiewicz
Keyword(s):  
Monoclonal Antibody ◽  
Schistosoma Mansoni ◽  
Fasciola Hepatica ◽  
Passive Immunization ◽  
Immune Serum ◽  
The Other ◽  
Passive Protection ◽  
Igm Antibody

SUMMARYTwo hybridomas secreting monoclonal IgM antibody to Schistosoma mansoni have been isolated following fusion of spleen cells from Balb/c mice immunized with living S. mansoni and NS1 myeloma cells. One monoclonal IgM antibody (WP66.4) mediated about the same level of passive protection against a challenge infection as immune serum from mice with a chronic S. mansoni infection. The other monoclonal antibody (WP66.2) did not give a significant level of passive protection. This result indicates that the effective monoclonal antibody recognizes an antigen which may be a valuable candidate for experimental vaccination. In vitro one monoclonal antibody (WP66.4) caused a much higher level of complement-dependent cytotoxicity than the other (WP66.2), suggesting a possible mechanism for the effect observed in vivo. With indirect immunofluorescence both monoclonal antibodies reacted with surface determinants on living S. mansoni schistosomula, adult worms and miracidia but these determinants were not detected on cercariae or lung schistosomula. Neither monoclonal antibody cross-reacted with S. haematobium schistosomula or Fasciola hepatica metacercariae, indicating a possible use for these reagents in differential diagnosis of S. mansoni infections.

In Vivo Effect of Suloctidil as an Antiplatelet Agent

1979 ◽  
Vol 41 (03) ◽  
pp. 465-474 ◽  
Author(s):  
Marcia R Stelzer ◽  
Thomas S Burns ◽  
Robert N Saunders
Keyword(s):  
Ex Vivo ◽  
Antiplatelet Agent ◽  
Ratio Method ◽  
Platelet Aggregate ◽  
Permanent Effect ◽  
Platelet Aggregates ◽  
5 Ht Uptake ◽  
High Doses

SummaryThe relationship between the effects of suloctidil in vivo as an antiplatelet agent and in vitro as a modifier of platelet serotonin (5-HT) parameters was investigated. Suloctidil was found to be effective in reducing platelet aggregates formation in the retired breeder rat as determined using the platelet aggregate ratio method (PAR) with an ED50 of 16.1 mg/kg 24 hours post administration. In contrast to the hypothesis that 5-HT depletion is involved in the anti-aggregatory mechanism of suloctidil, no correlation was found between platelet 5- HT content and this antiplatelet activity. Reduction of platelet 5-HT content required multiple injections of high doses (100 mg/kg/day) of suloctidil. Suloctidil administration for 8 days at 100 mg/kg/day, which lowered platelet 5-HT content by 50%, resulted in no permanent effect on ex vivo platelet 5-HT uptake or thrombin-induced release, nor alteration in the plasma 5-HT level. However, these platelets exhibited a short-lived, significant increase in percent leakage of 5-HT after 30 minutes of incubation. Therefore, suloctidil treatment at high doses may with time result in platelet 5-HT depletion, however this effect is probably not related to the primary anti-aggregatory activity of the drug.

scholarly journals To Divide or Not to Divide? How Deuterium Affects Growth and Division of Chlamydomonas reinhardtii

Biomolecules ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 861
Author(s):  
Veronika Kselíková ◽  
Vilém Zachleder ◽  
Kateřina Bišová
Keyword(s):  
Cell Cycle ◽  
Chlamydomonas Reinhardtii ◽  
Cell Cycle Progression ◽  
Model Organism ◽  
Cycle Progression ◽  
Synchronous Cultures ◽  
Multiple Fission ◽  
First Choice ◽  
High Doses

Extensive in vivo replacement of hydrogen by deuterium, a stable isotope of hydrogen, induces a distinct stress response, reduces cell growth and impairs cell division in various organisms. Microalgae, including Chlamydomonas reinhardtii, a well-established model organism in cell cycle studies, are no exception. Chlamydomonas reinhardtii, a green unicellular alga of the Chlorophyceae class, divides by multiple fission, grows autotrophically and can be synchronized by alternating light/dark regimes; this makes it a model of first choice to discriminate the effect of deuterium on growth and/or division. Here, we investigate the effects of high doses of deuterium on cell cycle progression in C. reinhardtii. Synchronous cultures of C. reinhardtii were cultivated in growth medium containing 70 or 90% D2O. We characterize specific deuterium-induced shifts in attainment of commitment points during growth and/or division of C. reinhardtii, contradicting the role of the “sizer” in regulating the cell cycle. Consequently, impaired cell cycle progression in deuterated cultures causes (over)accumulation of starch and lipids, suggesting a promising potential for microalgae to produce deuterated organic compounds.

scholarly journals Moluscos límnicos de uma área do Alto Araguaia (Brasil)

1991 ◽  
Vol 25 (3) ◽  
pp. 179-183 ◽  
Author(s):  
Horácio Manuel Santana Teles ◽  
Renata Piva Almeida Leite ◽  
Francisco Luiz Rodrigues
Keyword(s):  
Schistosoma Mansoni ◽  
Fasciola Hepatica ◽  
Biomphalaria Straminea

São mostrados os resultados do levantamento dos moluscos de água doce de 5 municípios da área de influência de uma usina hidrelétrica em estudo, formada pelas redondezas da Cachoeira Couto Magalhães no Rio Araguaia. Foram examinados 624 moluscos procedentes de amostras coletadas em 20 coleções hídricas. O exame revelou a ocorrência de 8 gastrópodos pulmonados e um prosobrânquio, além de um bivalvo esferídeo. Devido ao envolvimento com a saúde pública, merece destaque o encontro de Biomphalaria straminea e Lymnaea columella, respectivamente hospedeiros intermediários de Schistosoma mansoni e Fasciola hepatica.

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