Fourteen-day-old schistosomula obtained from mice previously infected were surgically transferred to the portal vein of receptor mice. Another group of mice was infected with cercariae by transcutaneous route. After 90 days, those groups were challenged with 100 cercariae, transcutaneously, as well as a control group. Two weeks later the animals were perfused and mature and immature worms count...

Since skin is the only route of entry of the parasite in schistosomiasis patients, intervention at the level of skin penetration should control the infection. Several compounds were screened for their ability to protect against cercarial penetration. Hinokitiol (beta-thujaplicin) was found to have a significant cercaricidal effect in vitro, although there is no information on its cercaricidal m...

The cercaria morphology of Echinochasmus japonicus was investigated using light and scanning electron microscopy. Cercariae, liberated from naturally infected snails (Parafossarulus manchouricus), had ovoid bodies and diminutive tails. The cercaria tegument was covered with minute spines. Four type II sensory papillae were observed on the dorsal side of the oral sucker, and type I papillae were...

Schistosoma mansoni cercariae in water were shown to possess a largely aerobic energy metabolism, the Krebs cycle being the main terminal of carbohydrate breakdown. A metabolic transition towards a more anaerobic breakdown of carbohydrate could be achieved by incubation conditions which also stimulated biological transformation. Incubation of cercariae in a simple salt medium containing 5 mM gl...

A comparative histopathological study of three snails species--Biomphalaria glabrata, B. tenagophila and B. straminea--which had been infected with Schistosoma mansoni miracidia revealed similar qualitative features; consisting of areas of sporocyst proliferation and differentiation associated with reactive host reaction, at the time they were actively eliminating great number of cercariae. How...

Present report demonstrates that repeated radiation of Schistosoma mansoni-infected Biomphalaria glabrata, totaling 15,000 rads, caused a sudden, albeit transient, suppression of cercarial shedding. Initially, sporocysts practically disappeared from the snail tissues. The more resistant developing cercariae presented nuclear clumping and vacuolation, before undergoing lysis. No host tissue reac...

Trematodes are recognized as a group of emerging parasites in tropical countries. We identified a trematode as a cause of ocular granulomas that developed in children who bathed in ponds or rivers in South India. DNA was isolated from patients' surgically excised granulomas and from the trematode cercariae (larvae) released by the snail Melanoides tuberculata in water in which the children bath...