Oleanolic acid induces G₂/M phase arrest and apoptosis in human hepatocellular carcinoma Bel-7402 cells / 中国中药杂志

This study was to examine the mechanism of oleanolic acid (OA) induces G2/M phase arrest and apoptosis in human hepatocellular carcinoma Bel-7402 cells. MTT and trypan blue exclusion test assay were adopted to detect the proliferate status of cells treated with OA. We assayed the cell cycle by flow cytometry using PI staining. Apoptosis was determined by Annexin V-FITC staining and PI labeling. The expressions of cycle related proteins and apoptotic related proteins were determined by Western blot analysis. OA strongly inhibited human hepatoma cells proliferation. When Bel-7402 cells were pretreated with OA for 24 h, OA induced apoptosis and G₂/M phase cell cycle arrest in a concentration-dependent manner. Analysis of the cell cycle regulatory proteins demonstrated that OA decreased the protein levels of cyclin B1, but increased the protein levels of p-Cdk1 (Tyr15) and p-Cdc25C (Ser 216). Moreover, OA modulated the phosphorylation of protein kinases Chk1 and p2l. Western blotting assay also showed significant decrease of Bcl-2 protein expression and increase of Bax protein expression, the cytosol Cyt c level, cleaved-caspase-9 and cleaved-caspase-3 activity. These data suggest that OA produces anti-tumor effect via induction of G₂/M cell cycle arrest and apoptosis.

Gene mutation in the areas of PreC/C and BCP of HBV DNA / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To investigate the gene mutation in the areas of pre core/core (Pre C/C) and basic core promotor (BCP) of HBV DNA and its clinical significance.</p><p><b>METHODS</b>The nt 1 735-1 965 segment of HBV DNA was amplified with PCR in 54 cases with chronic hepatitis B and 10 cases with post-hepatitis cirrhosis. Then the PCR product was sequenced.</p><p><b>RESULTS</b>There were 168 site mutations in 48.5% (33/68) cases with hepatitis B. The first ten mutation sites were nt 1 764 (58.8%), 1 762 (48.5%), 1 799 (21.0%), 1 766 (14.7%), 1 896 (13.2%), 1 754 (8.8%), 1 899 (8.8%), 1 768 (7.4%), 1 814 (7.4%) and 1 913 (7.4%). Three rare mutations of nt 1907, 1 922 and 1 923 were also detected. The mutations of nt 1 896, 1 764 and 1 762 were found in 16.7%, 35.2% and 35.2% of chronic hepatitis, and in 30.0%, 60.0% and 60.0% respectively of post-hepatitis cirrhosis cases. There was statistical significance between the two groups (P < 0.01).</p><p><b>CONCLUSION</b>The mutations in the areas of Pre C/C and BCP of HBV DNA might possibly be associated with liver fibrosis. There are many mutation sites in HBV DNA and mutation occurs frequently, therefore gene sequencing is helpful to the design of gene chip and to clinical application.</p>

Molecular genetic mechanism of sodium arsenite on growth and development / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the effects of sodium arsenite on gene expression related to growth and development and explored the molecular mechanism of arsenic effects using gene chips.</p><p><b>METHODS</b>Normal human hepatic cells were dripped on chips and then hybrided with the first strand of cDNA from hepatic cell exposed to different concentration of sodium arsenite. Gene sequence of clone differently expressed was determined and then defined which gene it was and finally those genes which associated with growth and development were identified.</p><p><b>RESULTS</b>The p55 gene expression level of two experimental groups was severaly 2.21 and 2.93 times as the control group. The PL gene level of two experimental groups were 0.13 and 0.27 times as the control group, and the HOXA10 gene level was 0.22 and 0.35 times of the control group. These results indicated that sodium arsenite increase p55 gene expression, and inhibited PL and HOXA10 gene expression.</p><p><b>CONCLUSIONS</b>The sodium arsenite could affect the gene expression related to growth and development and it is shown that the molecular genetic mechanism of sodium arsenite is related to growth and development.</p>

Rapid detection of the genotyping of hepatitis C virus using DNA chip with coloration methods / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To develop a new DNA chip with coloration, which can be used for rapid and economical detection of the genotyping of hepatitis C virus (HCV).</p><p><b>METHODS</b>Probes and primers were designed according to the sequence of HCV 5' non-coding region (5' NCR) to fabricate DNA chip. Experimental group consisted of 60 positive serum samples and control group consisted of 20 negative serum samples. To obtain the aimed gene, then they were hybridized with DNA chip. Finally, the results showed in a nylon film. The results of DNA sequencing of samples were used as the control in double blind experimental.</p><p><b>RESULTS</b>Using DNA chip, HCV was detected in positive of all serum specimens of experimental group and negative in control group. The determination of HCV genotype by DNA chip showed corresponding rate of 96.7% with those by sequence assay.</p><p><b>CONCLUSION</b>It showed higher specialty and sensitivity using DNA chip to detect the genotype of HCV. It would be valuable for the clinical genotyping of HCV</p>

Establishing DNA chip technique for detecting hepatitis C virus genotypes and primary application / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To establish a new method based DNA chip technique for detecting HCV genotypes.</p><p><b>METHODS</b>Genotyping probes were designed according to the sequence of HCV 5' NCR to generate DNA chip. The probes on DNA chip contains 5 major genotypes and 8 subtypes. The DNA fragment amplified by labeling Cy5 fluorescence was hybridized with DNA chip.</p><p><b>RESULTS</b>Fifty-five out of 65 isolates detected by DNA chip belonged to 1b- DNA sequencing of form a part of the isolates was used as the control. The results of both were completely consistent.</p><p><b>CONCLUSION</b>The method is simple and rapid with high specificity and sensitivity. It can be applied in detection of HCV RNA and genotypes.</p>