The assay system for antibody responses against Em2, the most specific antigen for serodiagnosis of alveolar echinococcosis (AE), has been established by enzyme-linked immunosorbent assay (ELISA) but not by Western blot assay, since Em2 antigen is not protein but carbohydrate in nature. Recently we reported that previously undescribed protein epitopes, designated Em18 and Em16 due to their molecular weights, were good serologic markers for AE by Western blot analysis. It has been shown that Em18 and Em16 are the only two epitopes recognized by commercially available weak positive (cut off) sera for the Em2plus-ELISA.

To determine the minimum effective dose of praziquantel against Hymenolepis diminuta in rats, 5.0 mg/kg, 2.5 mg/kg, 1.0 mg/kg, 0.5 mg/kg, 0.1 mg/kg, or 0.05 mg/kg praziquantel were given to each of five experimentally infected rats in six groups. Faecal samples from each rat were examined for worms on day 10. Based on the results of faecal examination and autopsy, the minimum effective dose of praziquantel against Hymenolepis diminuta in rats was determined to be 0.5 mg/kg.

Female ICR mice, 5 to 6 weeks old, were exposed by stomach tube to 25 metacercarial cysts of Echinostoma caproni per mouse. At 14 days post-exposure, mice were fed by stomach tube clorsulon (1000 mg/kg, 25 mg/kg, 500 mg/kg and 100 mg/kg) or rafoxanide (50 mg/kg, 25 mg/kg and 5 mg/kg) dissolved in dimethy lsulphoxide (DMSO) carrier and mebendazole (1000mg/kg and 500 mg/kg) or arprinocid (100 mg/kg and 50 mg/kg) suspended in a2:1 polyethylene glycol (PEG)/DMSO carrier. All drugs were obtained from Meerck In. (Rahway, New Jersey, USA) and only single dose regimes were used. Experimentally infected mice that served as controls received either DMSO or 2:1 PEG/DMSO carriers or were not given the carrier. Mice were necropsied 15v, 16, 18 and 20 days post-exposure to worms. Doses of 100 mg/kg of clorsulon and 50 mg/kg of rafoxanide were 100% effective in eliminating the echinostomes on day 1 post-administration of the anthelmintics. Mebendazole and arprinocid were ineffection in eliminating worms at 1 or 2 days post drug daministration.

Fifteen female ICR mice, 6–8 weeks old, were each exposed to 25 metacercarial cysts of Echinostoma caproni. To determine the effects of withholding food on survival, size and distribution of E. caproni in ICR mice, two groups of five each were maintained without food for 1 day (group A) or 2 days (group B) prior to necropsy. Group C consisted of five mice maintained with food for the duration of the experiment. All mice were necropsied at 12 days postinfection. There was no significant difference in worm survival, body area or distribution between group A and C or group B and C mice. The results of this experiment show that short-duration removal of food has no effect on worm survival, size or distribution of E. caproni adults in the small intestine of the ICR mouse.

Errata

Volume 69 Pages 113–117 For “mm” read “μm” throughout