| Schistosomiasis japonica continues to be a significant parasitic disease in our country in terms of social and economic impact and public health importance. As a essential part of comprehensive measures for schistosomiasis, chemotherapy aimed to control and destroy source of infection by getting rid of infection rate and infectiosity of human and animals for its antiparasitic effect in the body. Drug treatment and snail elimination has been already considered to be two confirmative methods of comprehensive measures for schistosomiasis in countries that patients were primary orgin of infection. Artemisinin derivatives as artesunate have been shown to be efficacious in chemoprophylaxis of and chemotherapy for Schistosoma japonicum and Schistosoma mansoni infections and has played positive role in floods affair and epidemical treatment. In order to provide more effective and reasonable chemotherapy reference and basis for patients of immunodeficiency, study on the relationship between immune function of host and the antischistosomal effect of artesunate was made. In addition, autoflurescence of adult Schistosoma japonicum has been studied by fluorescence microscope and confocal laser scanning microscope in our research.Part 1 Influence of immune suppression on the antischistosomal effect of artesunateTo investigate the effects of artesunate against the Schistosoma japonicum in the condition of the host immunosuppressed. Mice infected with cercarie of Schistosoma japonicum were divided into four groups randomly: control group , hydrocortisone treated group (HC group), artesunate treated group (Art group) and hydrocortisone plus artesunate treated group(HC+Art group). HC was gived to the mice by the way of intraperitoneal injection from the 7th day after infection , 25mg/kg.d and continued 7 days.Then, Art was gived 400mg/kg by intragastric administration. All of the mice were sacrificed and the worms were obtained in the 7th week after infection. Counted the worms of every group separately and the data statistical analysis was runned by the software of SPSS 13.0. Similar method was used to model and experiment. After a week of HC administration, Art was gived to mice on the 21st day after infection.The flukes were obtained and stained with hydrochloric carmine 7 weeks post-infection. The results showed that the worm reduction rate of Art group was significantly different from HC+Art group (33.00% vs 19.92%), moreover, that did not differ significantly between HC group and HC+Art group (19.92% vs 19.28%). Samples stained with hydrochloric carmine also implied that intestinal canal damage of Art group were more serious than HC+Art group. It has been demonstrated that the antischistosomal effect of artesunate has a close relation with the immunological function of host. Especially, artesunate even could not work effectively under condition of immunosuppression. Normal immunity of the host may be one of the important preconditions of the antischistosomal effect of artesunate.Part 2 Study on autofluorescence and confocalλscanning characteristic of adult Schistosoma japonicumTo study the autofluorescence andλscanning characteristic of adult S. japonicum which would provid spectroscopical referenced information for fluorescence imaging analysis and biological identification. The flukes were obtained from laboratory-infected mice by conventional perfusion six weeks post-infection. The paired worms were separated in stroke-physiological saline solution to enable the male and felmale to be analyzed separatedly. Different excitation lights as ultraviolet light, blue light and green light were used to excitate the autofluorescence of adult S.japonicum. In order to gain spectroscopical information of male worms,λscanning procedure was selected on confocal laser scanning microscopy with seven different excitation lights which wavelengthes were 405nm,458nm,476nm,488nm,514nm,543nm and 633nm. The results showed that the adult worms emited several different kinds of autofluorescence irradiated by different excitation lights, including blue,flavo-green and red, and the optimal microscopic condition for observation was be excited by blue light;the autofluorescence distribution of female worms were complicated than male's.Analyzed by software installed in confocal laser scanning microscopy, theλscanning figures of oral sukers indicated that the fluorescence spectra of male worms distributed widly. Irradiated by excitation light of 405nm,488nm,514nm and 543nm respectively, the corresponding responsive emission wavelength is 490-510nm,550-570nm,560-580nm and 590-600nm,and lasers of 488nm and 514nm are considered befitting excitation lights.However, 458nm,476nm,633nm could not achieve satisfactory irradiating effect.
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