RESUMO
It is unknown whether MIRU-VNTR (Mycobacterial Interspersed Repetitive Unit-Variable Number of Tandem Repeat) is associated with drug resistance of Mycobacterium tuberculosis. The purpose of this study was to explore the ability of 24 MIRU loci to predict the drug resistance of Isoniazid (INH), Rifampicin (RFP), Streptomycin (SM), Ethambutol (EMB) and Pyrazinamide (PZA). We collected the drug resistance and MIRU loci information of 109 strains of M. tuberculosis from an open database. The results of multivariate logistic regression showed that the VNTR polymorphism of MTUB04 was related to INH resistance [odds ratio (OR) = 2.82, P = 0.00], RFP resistance (OR = 1.91, P = 0.02), SM resistance (OR = 1.98, P = 0.01) and EMB resistance (OR = 1.95, P = 0.03). MIRU40 was associated with INH resistance (OR = 2.22, P = 0.00). MTUB21 was connected with INH resistance (OR = 1.63, P = 0.02) and SM resistance (OR = 1.69, P = 0.01). MIRU26 was correlated with SM resistance (OR = 1.52, P = 0.04). MIRU39 was associated with EMB resistance (OR = 4.07, P = 0.02). The prediction power of MIRU loci were 0.84, 0.70, 0.85, and 0.74 respectively for INH (predicted by MTUB04, MIRU20, and MTUB21), RFP (predicted by MTUB04), SM (predicted by MTUB21 and MIRU26) and EMB (MTUB04 and MIRU39) through ROC analysis. Our results showed that MIRU loci were related to anti-tuberculosis drug and could predict the drug resistance of tuberculosis.
RESUMO
Objective According to results from the two-month consecutive surveillance program in Maanshan,six suspected cases of non-O1 non-O139 Vibrio (V.) cholerae infection,were found that called for identification of pathogens as well as molecular-epidemiological analysis to determine the aggregation of the epidemic situation.Methods Biochemical and serotype identification,hemolysis test,and drug sensitive test were used to detect the drug resistance spectrum.Real-time PCR and conventional PCR were used to detect the presence of V.cholerae specific genes,virulent genes and its related genes,including ompW,ctx,tcpA,toxR,hlyA,zot,ace,rstR and g ⅢCTX.Pulsed-field gel electrophoresis (PFGE) was used to analyze the molecular type of strains.Results All the six isolates of non-O 1 non-O 139 V.cholerae were identified by biochemical and serologic tests,and appeared to be β hemolytic.Twelve out of the 14 kinds of drugs showed 100％ sensitive.All isolates were positive of ompW gene by real-time PCR,but negative for ctx,tcpA,zot,ace,rstR and gⅢ CTK.Five of the six isolates were positive for toxR and hlyA,except for strain 1001434446.All strains had different PFGE types,but two strains had similar types.All strains had a low similarity compared to the toxigenic V.cholerae.Conclusion Six cases ofnon-O1 and non-O139 nontoxigenic V.cholerae infection appeared in the same period.Along with epide(m)iological information,we noticed that these cases had a sporadic nature,but frequently appeared in the same area.We got the impression that public health measurements should be strengthened,with special attention paid to those diarrhea outbreaks caused by non-O 1 /non-O 139 strains since V.cholerae had appeared in low incidence.
