Objective To study the correlation between the drug-resistance variation and the genotypes of hepatitis B virus (HBV)detected by the PCR-reverse dot blot and the relation between the HBV variation loci with the liver function indexes and HBV DNA viral loading.Methods The serum samples from 462 patients with chronic hepatitis B treated by oral nucleoside drugs were screened.The PCR-reverse dot blot was adopted to detect the drug-resistance gene mutation loci and genotypes.The correla-tion between the HBV drug-resistance mutant with the genotypes,liver function indexes and HBV DNA viral loads was performed. Results Among 462 patients taking nucleoside drugs for treating chronic hepatitis B,45 drug-resistance mutants were detected with the mutation rate of 9.74%;in which,16 cases (35.5%)were 180M and 204I/V mutant,6 cases(13.3%)were 204V,13 ca-ses(28.9%)were 204I mutant,3 cases (6.7%)were 180V mutant and 3 cases(6.7%)were 236T mutant.The HBV genotyping showed 105 cases of genotype B,337 cases of genotype C,0 case of genotype D and 2 cases of other genotypes.Conclusion (1)The HBVgenotypes in Maoming area may be different from the genotypes in other southern regions and is dominated by HBV-C geno-type.(2)The PCR-reverse dot blot method is a detection method for fastly and accurately finding the drug-resistance loci after nu-cleosides therapy.(3)The clinical analysis demonstrates that the drug-resistance mutation loci has no correlation with the liver func-tion index ALT(P >0.05),but there was certain correlation between the drug-resistance mutation loci in hepatitis B and HBV DNA viral load(P <0.05).

Objective Plasma circulating DNA can be em-ployed in place of bone marrow examination for the auxiliary diagnosis of leukemia.This study aimed to explore the clinical application of the plasma DNA level in evaluating the effect of chemotherapy on chronic leukemia. Methods We collected blood samples from 52 patients with chronic myelogenous leukemia (CML) (33 in the chronic phase, 7 in the acceleration phase, and 12 in the blast phase) , 85 with chron-ic lymphocytic leukemia (CLL) (28 with complete remission, 27 with partial remission, and 30 with no remission), 4 patients with hairy cell leukemia (HCL), and 80 healthy subjects.We simultaneously obtained plasma DNA and recombinant plasmid DNA using the BI-LATEST DNA Kit and examined the human β-actin gene and the level of plasmid DNA by real-time quantitative PCR. Results Before chemotherapy, the median value of plasma DNA was 149.46(30.63-496.91)ng/ml in the CML and 101.54(69.10-258.14) ng/ml in the CLL patients, both significantly higher than in the healthy controls (19.05[12.67-25.92]ng/ml) (P<0.01).After chemotherapy, the plasma DNA level of the CML patients was remarkably decreased, but still higher than that of the controls ( P<0.01).The CML patients in the chronic phase showed a markedly higher level of plasma DNA (302.89[93.33-541.52]ng/ml) than those in the blast phase (43.19[23.54-70.03]ng/ml) and acceleration phase (28.11[16.21-92.07]ng/ml) (P<0.05).The CLL patients with CR exhibited a significantly lower level of plasma DNA (24.29[14.64-30.74]ng/ml) than those with PR (106.88 [96.23-143.25]ng/ml) and NR (460.73[284.57-653.38〗ng/ml) (P<0.01), but all dramatically higher than that of the healthy controls (P<0.01) Conclusion The quantification of plasma DNA has a clinical application value in evaluating the effect of chemo-therapy on chronic leukemia.

Objective To investigate the regulatory effects of miR-145 on MMP2 expression in lung adenocarcinoma cell A549 and the mechanism involved in the regulation.Methods Lipofectamine 2000 reagent-mediated miR-145 mimic or mimic negative control (NC) was transiently transfected into lung adenocarcinoma cell A549.The expression levels of miR-145 were determined by RT-PCR.MMP2 and β-catenin expression was detected by western blot.Lithium chloride (LiC1),the activator of Wnt/β-catenin pathway,and miR-145 mimic co-processed to act on A549 cells,then the expressions of MMP2 and β-catenin were detected by Western blot.Results The results of RT-PCR showed that the difference of miR-145 in miR-145 mimic group,NC group and blank group was statistically significant(F =296.30,P ＜0.05).western blot showed that the expression levels of MMP2 and nucleus β-catenin were significantly downregulated in miR-145 overexpression group compared with the control (q =8.98,26.59,all P ＜ 0.05).Additionally,the effects of co-processing factors on the cells showed that the activation of wnt/β-catenin pathway reversed the inhibition of miR-145 on MMP2 expression(q =49.47,P ＜ 0.05).Conclusion miR-145 may downregulate MMP2 expression through inhibition of Wnt/β-catenin pathway activity in lung adenocarcinoma cell A549.