[Development of colloidal gold immunochromatography assay strip for schistosomiasis diagnosis in domestic animals].

OBJECTIVE: To develop a quick and easy colloidal gold immunochromatography assay (GICA) strip for schistosomiasis diagnosis in domestic animals. METHODS: The reconstruction of Streptococcal Protein G (SPG) was designed and its gene was subcloned into plasmid pET-28a(+) to express in Escherichia coli. The recombinant SPG was purified and labeled with colloidal gold. The Schistosoma japonicum soluble egg antigen (SEA) and rSPG were blotted on the nitrocellulose membrane for the test line and control line respectively. The specificity, sensitivity and cross-reaction of the strip method were detected. RESULTS: The rSPG was successfully expressed and purified to label with colloidal gold. The colloidal gold immunochromatography assay strips were assembled and they could detect the sera of S. japonicum infected BALB/c mice, New Zealand white rabbits, buffalo and sheep successfully. Besides, the sensitivity of GICA strip was 100% in the sera of mice and the serum of rabbits with S. japonicum infection. The specificity was 100% in the serum of mice and the sera of rabbits with free of infection. The sensitivity was 100% in the sera of sheep with miracidia of S. japonicum hatching from the stool and the specificity was 88.46% in the sera of sheep without that. The sensitivity was 94.44% in the sera of buffalo with miracidia hatching from the stool and the specificity was 100% in the sera of buffalo without that. The cross-reaction rate was 5.88% in Paramphistomum. CONCLUSION: The GICA strip can successfully detect a variety of S. japonicum infected domestic animals and may be a useful tool for screening on a large scale in the endemic areas.

[Distribution characteristics of deposited eggs and pathological changes in viscera of New Zealand white rabbits infected with Schistosoma japonicum at different time].

OBJECTIVE: To study the distribution characteristics of deposited eggs and pathological changes in the viscera of animal infected with Schistosoma japonicum at different time. METHODS: New Zealand white rabbits were infected artificially with quantitative S. japonicum miracidia, then the distribution characteristics and the hatchability of schistosome eggs as well as the pathological changes of the corresponding viscera of the rabbits 42 and 60 d post-infection were observed and compared. RESULTS: On the 42nd day post-infection, among all the viscera observed, the percentage of eggs deposited, the number of eggs per gram and the hatchability were the highest in the liver, while on the 60th day post-infection, the tissues and organs with the highest values of the above 3 indexes were the liver, rectum and upper section of the small intestine, respectively. From 42 day to 60 day post-infection, the liver of infected rabbits became swelling, hardening and lost elasticity, the color changed from black to dark grey, and egg nodules gradually appeared in the different sections of the small intestine, and also the mucosal hyperemia, edema and egg nodules were seen in the colon, cecum and rectum. The lesion levels tended to be correlated with the deposition of eggs. CONCLUSION: The amount and the density as well as the hatching rate of deposited eggs of S. japonicum in the viscera of infected rabbits at different time are different, and the lesion level in the host is correlated with the deposition of eggs.

[Relationship among pathological changes in Liver tissues and level of serum HBV DNA, HBeAg and ALT of 194 patients with chronic hepatitis B].

OBJECTIVE: To study the relationships among pathological and immunohistochemical changes in liver tissues, and the HBeAg, HBV DNA, ALT level in the patients with chronic hepatitis B. METHODS: Pathological and immunohistochemical examinations of liver tissue liver function tests, serum HBV and HBV DNA detection were performed in 194 patients with chronic hepatitis B. RESULTS: There was significant difference between the serum HBeAg positive group and the negative group in G2, G3-4 S2, S3-4 in liver tissues; The serum HBV DNA level of the groups S0 and S1-4, and the hepatic activity index between the groups G0-1 and G2-4 were significantly different. And the hepatic HBcAg positive group and HBcAg negative group were significantly different too. There was no significant difference between the HBsAg level in liver tissues as "+" group and the "++ - +++" group. The pathological diagnosis as S1 or (and) G2 is respectively 28.57%, 53.33%, 80.15%, 77.88% among the four groups with normal-mild-moderate-severe elevated serum ALT level. CONCLUSION: Serum HBV DNA correlated with HBcAg expression in liver tissue; the HBsAg level in liver tissues have no relationship with the serum HBV DNA level. The patients with low serum HBV DNA level may have high index of hepatic activity and hepatic fibrosis. Asymptomatic carriers and patients with low serum ALT level should be encouraged to accept liver biopsy. It can determine the degree of liver inflammation and fibrosis and timing of treatment.