Effects of gambogic acid on the regulation of steroid receptor coactivator-3 in A549 cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the effects of gambogic acid (GA) on the proliferation inhibition and apoptosis induction in Human lung adenocarcinoma A549 cells in vitro, as well as the regulation of steroid receptor coactivator-3 (SRC-3) to explore the relationship between them.</p><p><b>METHODS</b>The effect of GA on the growth of A549 cells was studied by MTT assay. Apoptosis was detected by Hoechst 33258 staining. The localization of SRC-3 was determined by confocal laser scanning microscopy. Western blot and RT-PCR technique were applied to assess the expression of SRC-3.</p><p><b>RESULTS</b>GA presented a striking proliferation inhibition potency on A549 cells in vitro, as well as apoptosis induction activity in a time- and dose-dependent manner. The IC(50) value for 24 h was (3.17 +/- 0.13) micromol/L. Overexpression of SRC-3 was found in A549 cells, whereas the SRC-3 protein and mRNA expression levels were significantly downregulated in A549 cells induced by GA in a dose-dependent manner. The location of SRC-3 was situated mainly in the cell nuclei.</p><p><b>CONCLUSION</b>GA exhibits a potent proliferation inhibition and apoptosis induction in human lung adenocarcinoma A549 cells, which might correspond to the downregulation of the expression of SRC-3. Thus, it promises to be a new target drug for lung cancer treatment.</p>

Experimental study on enzyme dot assay for detection of hemorrhagic fever with renal syndrome antigen / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To establish a new and efficient method(IEDA) for detection of hemorrhagic fever with renal syndrome virus (HFRSV) antigen.</p><p><b>METHODS</b>An immune enzyme dot assay (IEDA) with mixture of three sorts anti-HFRSV-IgG, which was obtained from rabbit vaccinated with EHFV R22, Chen and Hubei strain was employed to detect HFRSV antigen in serum and urine from epidemic hemorrhagic fever (EHF) patients, and compared with indirect immune fluorescence assay (I-IFA), 76 serum samples and 40 urine samples were detected in this study.</p><p><b>RESULTS</b>The results showed that the total positive rate of HFRSV antigen detected by IEDA was 73.68% in serum and 65.00% in urine, while that detected by I-IFA was 75.00% and 70.00%, respectively. The positive rate in primary phase (within 5 days) of HFRSV antigen detected by IEDA was 94.34% in serum and 83.33% in urine, while that detected by I-IFA was 64.42% and 55.56%, respectively, there was significant difference in both serum and urine detections. Correlation study showed a high correlation in the result of IEDA and I-IFA.</p><p><b>CONCLUSION</b>The results of this study suggested that the IEDA, as compared with I-IFA, was a more specific, sensitive, rapid and simple method with higher positive rate in primary phase. IEDA could be widely used for early diagnosis of HFRS in hospital at grassroots level.</p>

Observation of the Expression of HCV NS 5 Antigen in vitro by the SABC Immunological Techniques and Gold-labeled Colloid Electron Microscopy Method / 中国病毒学

To study the expression of HCV non-structure 5 antigen in vitro, a human HepG2 cell line was incubated with a HCV RNA positive serum. The S ABC i mmunological techniques and gold-labeled colloid electron microscopy method wer e employed to examine for the viral proteins in those cells. The HCV non-struct ure 5 antigen was first detected in the HepG2 cells at 72 hours post incubation. The antigen was continuously observed in the cytoplasm or on the membrane as we ll on the cell wall of the HepG2 cells even after 1, 2, 3 and 4 weeks post incub ation. The observation of HCV non-structure 5 antigen continuously expressed in the HepG2 cells strongly indicates that the cells may have been infected by HCV virus and the virus may have replicated in the cells. Therefore, the HepG2 cell line may be served as a potential host for establishment of HCV infection and p ropagation in vitro.