ObjectiveTo explore distribution characteristics of drug-resistant mutations and analyze drug-resistant genotypes in Mycobacterium tuberculosis in Deyang district, Sichuan. MethodsA total of 257 patients infected with Mycobacterium tuberculosis and positive for mycobacterium tuberculosis DNA who were detected from February 2010 to March 2013 were included in our research. Drug-resistance mutations were detected and analyzed using gene chip technology combining by polymerase chain reaction (PCR) and reverse dot hybridization (RDB). ResultsIn these 257 pulmonary tuberculosis patients, drug-resistance mutations were detected in 49 with pulmonary tuberculosis. Drug-resistance mutation rate at katG 315, rpsL 43, embB 306 and rpoB 531 (S531L) was 11.67% (30/257), 7.00% (18/257), 4.28% (11/257) and 3.89% (10/257), respectively. In 234 initially treated pulmonary tuberculosis patients, the rate of isoniazid-resistant genotype, rifampicin-resistant genotype, ethambutol-resistant genotype, streptomycin-resistant genotype and multi-drug resistant genotype was 9.83%, 4.27%, 3.42%, 5.13% and 2.99%, respectively. In 23 retreated pulmonary tuberculosis patients, these rates was 52.17%, 26.09%, 13.04%, 43.48% and 13.04%, respectively. ConclusionIn Deyang district, Sichuan, drug-resistant genotypes for isoniazid, rifampicin, ethambutol and streptomycin are detected in Mycobacterium tuberculosis. Most of the drug-resistant mutations occur at katG 315, rpsL 43, embB 306 and rpoB 531. The rates of drug-resistant genotypes and multi-drug resistance in initially treated pulmonary tuberculosis patients are lower than those in retreated patients. Multi-drug resistant rate is relatively low in our research.
ObjectiveTo investigate the correlation of spontaneous YMDD mutation in different hepatitis B virus (HBV) genotypes with HBV-related hepatocellular carcinoma (HCC). MethodFrom May 2010 to May 2012, 110 HBV-related hepatocellular cancer patients not treated by anti-virus drugs and 1 079 chronic HBV infectors (including asymptomatic HBV carriers, chronic hepatitis B patients, and HBV-related liver cirrhosis patients) were included in our study. HBV YMDD mutation was detected by fluorescence hybridization bioprobe polymerase chain reaction (PCR) and melting curve assay using Diagnosis Kit for HBV YMDD Mutation (Qiagen Biotechnology). Serum HBV genotype was detected by real time PCR using genotype specific TaqMan probe. According to data type, t-test, χ2-test and unconditional logistic regression were used for statistical analysis. ResultsIn the HCC group, genotype C virus, spontaneous YMDD mutation and genotype C virus with YMDD mutation were detected in 39 patients (35.5%), 16 patients (14.5%) and 14 patients (12.7%), respectively. In the chronic HBV infection group, HBV genotype C virus, spontaneous YMDD mutation and genotype C virus with YMDD mutation were detected in 153 patients (14.2%), 46 patients (4.3%) and 17 patients (1.6%), respectively. The difference between the two groups were statistically significant (χ2=33.368, P<0.001; χ2=21.353, P<0.001; χ2=48.889, P<0.001). Unconditional logistic regression analysis suggested that infection of genotype C virus and genotype C virus with spontaneous YMDD mutation might be important risk factors for the development of HCC[OR=2.943, 95%CI (1.778, 4.872), P<0.001; OR=5.989, 95%CI (2.394, 14.980), P<0.001]. ConclusionsInfection of genotype C virus with spontaneous YMDD mutation is tightly related with the occurrence of HCC and has important value for earlier warning of HCC.