Impaired biliary secretion of immunoglobulin A in vitamin A-deficient rats.

The effect of vitamin A deficiency on biliary secretion of IgA was investigated. Rats used in this study were rendered vitamin A deficient following withdrawal of retinoic acid from the diet of retinoate-cycled animals. This procedure allows a precise control of both the onset of deficiency and dietary protein-energy input.

Alterations of the surface tegument of Opisthorchis viverrini exposed to praziquantel in vitro and in vivo.

The in vitro and in vivo effects of praziquantel on the ultrastructural surface of Opisthorchis viverrini were investigated using scanning electronmicroscopy. For the in vitro study, adult flukes were collected from experimentally infected hamsters, and were incubated for various time intervals at 37 degrees C in Earle's basal medium containing praziquantel at final concentrations of 0.01-100 micrograms/ml.