[Cloning and Expression of Tibetan Sheep-origin Echinococcus granulosus Antigen B Gene and Protein Identification Using Immunological Method].

Objective: To clone and express the Tibetan Sheep-origin Echinococcus granulosus Antigen B8/2 Gene, and immunologically identify the encoded protein. Methods: The cDNA of EgAgB8/2 gene was amplified by RT-PCR. The prokaryotic expression vector pET-EgAgB8/2 was constructed and transformed into E. coli BL21（DE3） for expression. Proteins were extracted, separated in SDS-PAGE and identified by Western blotting. Results: The cloned EgAgB8/2 gene was 335 bp in length, and had a 98%-100% sequence homology with the reported cDNA sequence of EgAgB8/2, indicating the successful construction of the pET-EgAgB8/2 vector. SDS-PAGE revealed large amount of proteins in supernatant. Western blotting further confirmed the expression of the target protein. Conclusion: The EgAgB8/2 gene of Tibetan Sheep-origin in Qinghai is successfully cloned, and the constructed pET-EgAgB8/2 vector can be used to express the target protein.

[Analysis of the clinical information of 1,066 cases undergoing prostate magnetic resonance examination].

OBJECTIVE: To evaluate the variation of clinical data and referred purpose of prostate magnetic resonance (MR) examination in the past 12 years in Peking University First Hospital. METHODS: One thousand and sixty-six patients underwent prostate MR examination (1,296 exams) from May 1992 to Sept. 2004. The clinical data of the patients were retrospectively analyzed. The number of patients was counted and three groups were classified (diagnosing group, staging group and follow-up group) according to the purpose of prostate MR examination per year. For the diagnosing group, the clinical data of patient's age, symptom, level of serum prostate specific antigen (PSA), and the result of ultrasound or digital rectal examination (DRE) were evaluated. RESULTS: (1)The number of patients increased year by year in the past 12 years, and the majority of the increased patients required differential diagnosis. (2) Diagnosing group: the percentage of patients with the symptom of BPH increased year by year. The average level of serum PSA dropped and the percentage of patients with elevated PSA or with nodules detected by ultrasound or DRE referred for detection of prostate cancer or with the symptom of metastasis decreased. CONCLUSION: With the widespread screening of prostate cancer, more patients of early prostate carcinoma and non-tumoral lesion in prostate gland are examined by MR imaging.