RESUMO
Mice infected with Schistosoma japonicum were treated with a single oral dose of levo-praziquantel 75mg/kg or racemic praziquantel 150mg/kg. 10min-7d after administration of the drugs, the infected mice were sacrificed and the parasites were studied. The tegumental antigen of the integral worms and of. the worm sections were tested by IFA.10-30 min after treatment more than 50% of the tegumental surface of adult worm showed weak and small fluorescent spots in treated groups. 1-6h after treatment, the sucker and extremity of adult worm showed brighter fluorescent spots. From 6h after treatment, there were very bright fluorescent spots on the whole worm surface. 3d after treatment, the fluorescent intensity was weaker than before, and there was no significant difference between the levo-praziquantel group and racemic praziquantel group in the exposure of tegumental surface antigen. The results demonstrated that levo-praziquantel, just like the racemic-praziquantel, could disturb the tegumental metabolic course of the schistosomes, caused tegumental damage and exposure of adult worm surface antigen.
RESUMO
Schistosoma japonicum were obtained from infected rabbits 24 hours after treatment with lower dose praziquantel (30~40mg/kg). The drug-induced tegu-mental surface alteiations of the worms were studied by rcanning electron microscopy. In comparison with untreated worms, the ultrastructures of oral and ventral suckers in both male and female worms were not affected by praziquantel. Major surface alterations including pronounced swellings, erosions and ulcerations were observed,The results showed that the female worms of S. japonicum and those treated with praziquantel at a dosage of 40 mg/kg were more seriously damaged than the male worms and those treated with praziquantel at other dosages.
RESUMO
Schistosoma japonicum were obtained from infected rabbits 24 hours after treatment with praziquantel at a single dose of 30,35,40 mg/kg. The drug-induced alterations of histochemistry of the worms have been studied.The results indicated that the glycogen content and AKP (alkaline phosphatase) activities of the worms decreased markedly or disappeared as compared with those of untreated worms; however, the activities of ACP (acid phosphatase) in both treated and untreated worms revealed no apparent change.
RESUMO
The trichomonadicidal activity of tinidazole (Fasigyn) was evaluated by the ire vitro cultivation of Trichomonas vaginalis and Trichomonas hominis with different drug concentrations. The results showed that, after 48-hour incubation with tinidazole, the 100% lethal concentration was 20?g/ml. The trichomonadicidal effect of tinidazole was one titre lower than that of metronidazole. With regard to T. hominis, after 48-hour incubation with tinidazole, the 100% lethal concentration was 20?g/ml. In comparison with metronidazole, the trichomonadicidal effect of tinidazole was similar.
RESUMO
DNA from five isolates of Entamoeba histolytica were examined for their pathogenicity by polymerase chain reaction. Three isolates SH-3,SH-6,SH-8 were isolated from patients with acute amoebic dysentery, whereas SH-5 and SH-7 were isolated from asymptomatic cyst passers. Gel electrophoresis of PCR products showed that primers P11 , P12 for pathogenic strains could amplify genomic DNA extracted from SH-8 , and primers P13, P14 for non-pathogenic strains could amplify genomic DNA extracted from SH-3, SH-5, SH-6 and SH-7. Furthermore, zymodeme analysis and the reactivity of McAb 4G6, which recognizes the 30 kDa antigen of pathogenic E. histolytica indicated that only SH-8 was pathogenic, while the others were nonpathogenic. The results of the genotypic analysis by PCR were in accord with the phenotypic properties.It is suggested that there are differences in genomic DNA between pathogenic and non-pathogenic strains. PCR is a highly sensitive and specific method for genomic DNA analysis of E. histolytica.