OBJECTIVE The aim of the present study was to confirm observations on the concomitant immunity to Schistosoma mansoni in mice and assess its effects on the resistance of mice to a challenge infection. METHODS Cercariae from infected Biomphalaria glabrata were used to infect mice. Twenty mice were infected with a single dose of S. mansoni cercariae. The animals were randomly divided into two g...

In the present study, the efficacy of 6 different species of medicinal plants belonging to 5 different families against Biomphalaria alexandrina snails and Schistosoma mansoni stages were examined. During screening test of water suspension and methanol extract, results revealed that Oreopanax reticulatum (Family: Araliaceae) had the strongest molluscicidal activity against Biomphalaria alexandr...

Recent studies have suggested that host lipids are both a requirement for the human parasite Schistosoma mansoni and may play a role in evasion of host immunity. To study lipid utilization by this organism we have followed the uptake of fluorescent fatty acid and phospholipid analogs in two parasite stages, cercariae and schistosomula. As determined by both morphological and biochemical methods...

The life cycle of Centrocestus formosanus (Digenea: Heterophyidae) was to be successfully completed in the laboratory in the present study. Hundreds of the thiarid snail, Melanoides tuberculata, were collected from the main water course Mansouriya Canal, Giza Governorate, Egypt. The snails were individually exposed to artificial light to determine possible infection with trematode larvae. Fifte...

BACKGROUND & OBJECTIVES Vector ecology and taxonomy of snails is a prerequisite for controlling schistosomiasis in the tropics. The ecology of the freshwater limpet genus Ferrissia was investigated for detection of cercariae larvae in them, and taxonomic description of a new species of the genus Ferrissia. METHODS This study was conducted in 15 perennial streams from five different hills of s...

Three species of the pulmonate snails of the family Planorbidae have been reported from Korea; Gyraulus convexiusculus, Hippeutis (Helicorbis) cantori and Segmentina (Polypylis) hemisphaerula. Of these 3 species, only H. cantori is reported as the molluscan intermediate host of Neodiplostomum seoulensis, one of the important snail-borne human intestinal trematodes in Korea. However, S. hemispha...

Schistosomiasis continues to plague populations living in disease-endemic areas, and exposure to infective cercariae results in more than 200 million cases worldwide. Laboratory experiments were conducted to test whether a cercaricidal film applied directly to the water surface can reduce viability of cercariae. A distillate from inexpensive cedarwood oil enriched for cedrol in a mixed oil frac...

A transcriptional product of a gene encoding cathepsin B-like peptidase in the bird schistosome Trichobilharzia regenti was identified and cloned. The enzyme was named TrCB2 due to its 77% sequence similarity to cathepsin B2 from the important human parasite Schistosoma mansoni. The zymogen was expressed in the methylotropic yeast Pichia pastoris; procathepsin B2 underwent self-processing in ye...

Small ubiquitin-related modifier (SUMO) is involved in numerous cellular processes including protein localization, transcription, and cell cycle control. SUMOylation is a dynamic process, catalyzed by three SUMO-specific enzymes and reversed by Sentrin/SUMO-specific proteases (SENPs). Here we report the characterization of these proteases in Schistosoma mansoni. Using in silico analysis, we ide...