Tailored Synthesis of Catalytically Active Cerium Oxide for N, N-Dimethylformamide Oxidation.

Cerium oxide nanopowder (CeOx) was prepared using the sol-gel method for the catalytic oxidation of N, N-dimethylformamide (DMF). The phase, specific surface area, morphology, ionic states, and redox properties of the obtained nanocatalyst were systematically characterized using XRD, BET, TEM, EDS, XPS, H2-TPR, and O2-TPO techniques. The results showed that the catalyst had a good crystal structure and spherelike morphology with the aggregation of uniform small grain size. The catalyst showed the presence of more adsorbed oxygen on the catalyst surface. XPS and H2-TPR have confirmed the reduction of Ce4+ species to Ce3+ species. O2-TPR proved the reoxidability of CeOx, playing a key role during DMF oxidation. The catalyst had a reaction rate of 1.44 mol g-1cat s-1 and apparent activation energy of 33.30 ± 3 kJ mol-1. The catalytic performance showed ~82 ± 2% DMF oxidation at 400 °C. This work's overall results demonstrated that reducing Ce4+ to Ce3+ and increasing the amount of adsorbed oxygen provided more suitable active sites for DMF oxidation. Additionally, the catalyst was thermally stable (~86%) after 100 h time-on-stream DMF conversion, which could be a potential catalyst for industrial applications.

Measurement and Numerical Simulation of Coal Spontaneous Combustion in Goaf under Y-type Ventilation Mode.

In the process of advancing the working face, the temperature rise and oxidation characteristics of residual coal in goaf and the prediction of index gas are of great significance to mine fire prevention and safety production. Based on the coal spontaneous combustion test, the oxygen consumption and heat release characteristics of coal spontaneous combustion were analyzed by taking coal samples at the working face and carrying out temperature-programmed experiments in the laboratory. The characteristic temperature and index gas of coal spontaneous combustion were determined as the judgment bases of "three zones" of spontaneous combustion in goaf, and the influencing factors of coal spontaneous combustion in goaf under Y-type ventilation were analyzed. Based on the test results, the changes of gas composition in goaf during the advancing of the W1310 working face were monitored. According to the actual situation of the W1310 working face in the Gaohe energy mine of Lu'an group, the multifield three-dimensional numerical simulation calculation and analysis of gas composition in goaf were carried out, and the distribution of oxygen concentration field in goaf under different air volume ratios of machine roadway and air roadway was studied. Through the analysis of the parameters of porous media in the goaf, combined with the actual situation, the user-defined function was compiled for the key parameters such as porosity, viscous resistance coefficient, and inertial resistance coefficient of porous media in the goaf. The three-dimensional seepage field, gas concentration field, oxygen concentration field, and pressure field of the gas components in goaf during the advancement of the goaf working face were simulated. The comparison of the numerical simulation results with the field-measured results shows good agreement. In order to consider safety, the numerical simulation results with a wide oxidation temperature rise zone are used for linear regression, and the regression equation is used to dynamically determine the O2 concentration at a point away from the goaf and to determine the "three-zone" state of the point, which is of great significance to guide the progress of the working face and safe production.

Safety of Recanalization Therapy in Acute Ischemic Stroke Patients on Direct Oral Anticoagulant Therapy: An Updated Systematic Review and Meta-Analysis.

This review provides an updated assessment of the safety of recanalization therapy for Acute Ischemic Stroke (AIS) patients receiving direct oral anticoagulants (DOAC) therapy. We checked the literature for published observational from 1st January 1950 to 31st March 2021. The rate of symptomatic intracerebral hemorrhage (sICH), arterial recanalization rate, good functional recovery, and mortality at 3 months were investigated, and data were expressed as Risk ratio (RR) with a 95% confidence interval (CI). Publication bias, sensitivity analysis, and meta-regression analyses were conducted utilizing STATA software. 17 articles [14 for endovascular therapy (EVT) and 3 intravenous thrombolysis for (IVT)] were finally included in the review. AIS patients with DOAC therapy showed a decreased rate of sICH (RR = 0.85, 95% CI = 0.72 to 1.00, P = 0.04), and lower probability of good functional recovery at three months (RR = 0.79, 95% CI = 0.73 to 0.85, P < 0.001) than patients without anticoagulation therapy post EVT. However, no significant differences in sICH rates in AIS patients with DOAC therapy after IVT (RR = 0.87, 95% CI = 0.48 to 1.58, P = 0.64) were observed. AIS patients not prescribed DOAC after EVT had a higher mortality risk (RR = 1.29, 95% CI = 1.15-1.44, P < 0.001). Patients with AIS on DOAC therapy were found to have a lower incidence of sICH following EVT. However, no evidence of an increased bleeding risk in patients previously treated with DOAC after IVT was observed. Therefore, more detailed studies with biological data to monitor compliance and details on the size and etiology/severity of the incident ischemic lesion is needed.

Prognosis of Subtypes of Acute Large Artery Atherosclerotic Cerebral Infarction by Evaluation of Established Collateral Circulation.

BACKGROUND: The prognosis of acute ischemic stroke is related to collateral circulation, which is different with different pathogenesis. OBJECTIVE: To explore the prognosis of acute large atherosclerotic (LAA) cerebral infarction with different pathogenesis by assessing the establishment of collateral circulation. METHODS: 108 patients with acute LAA cerebral infarction in our hospital, who failed to thrombolytic or thrombectomy in the acute phase were selected and classified by Chinese ischemic stroke subclassification (CISS). They were evaluated by National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS). CT angiography (CTA) of head and neck were used to evaluate the collateral circulation for patients with large vessel stenosis or occlusion within one week of admission. The CTA collateral scores (CS) were recorded in a dichotomized fashion (ie, poor vs good). RESULTS: Patients with good CS had significantly lower NIHSS score and good prognosis at 2 weeks and 3 months than patients with poor CS (P < 0.001). The arterial-to-arterial embolization mechanism was the highest in the ratio of good CS and good prognosis at 3 months (P < 0.001). Multivariate Logistic regression analysis showed that baseline NIHSS score (OR=1.407, 95%CI:1.153-1.717, P=0.001) was an independent factor affecting poor CS. The NIHSS score at baseline (OR=0.604, 95%CI:0.436-0.837, P=0.002) and good CS (OR=39.552, 95%CI:8.908-175.618, P=0.000) were important predictors of good prognosis at 3 months. CONCLUSION: The prognosis and collateral circulation of acute LAA cerebral infarction with different pathogenesis was different. Baseline NIHSS score and collateral circulation had great impact on prognosis at 3 months.

Transmission of Mycobacterium tuberculosis in China: a population-based molecular epidemiologic study.

BACKGROUND: Understanding the transmission of Mycobacterium tuberculosis is essential for the development of efficient tuberculosis control strategies. China has the second-largest tuberculosis burden in the world. Recent transmission and infection with M. tuberculosis, particularly drug-resistant strains, may account for many new tuberculosis cases. METHODS: We performed a population-based molecular epidemiologic study of pulmonary tuberculosis in China during 1 July 2009 to 30 June 2012. We defined clusters as cases with identical variable number tandem repeat genotype patterns and identified the risk factors associated with clustering, by logistic regression. Relative transmission rates were estimated by the sputum smear status and drug susceptibility status of tuberculosis patients. RESULTS: Among 2274 culture-positive tuberculosis patients with genotyped isolates, there were 705 (31.0%) tuberculosis patients in 287 clusters. Multidrug-resistant (MDR) tuberculosis (adjusted odds ratio [aOR], 1.86; 95% confidence interval [CI], 1.25-2.63) and infection with a Beijing family strain (aOR, 1.56; 95% CI, 1.23-2.96) were associated with clustering. Eighty-four of 280 (30.0%) clusters had a putative source case that was sputum smear negative, and 30.6% of their secondary cases were attributed to transmission by sputum smear-negative patients. The relative transmission rate for sputum smear negative compared with sputum smear-positive patients was 0.89 (95% CI, .68-1.10), and was 1.51 (95% CI, 1.00-2.24) for MDR tuberculosis vs drug-susceptible tuberculosis. CONCLUSIONS: Recent transmission of M. tuberculosis, including MDR strains, contributes substantially to tuberculosis disease in China. Sputum smear-negative cases were responsible for at least 30% of the secondary cases. Interventions to reduce the transmission of M. tuberculosis should be implemented in China.

[Prevalence and risk factors on the resistance related to second-line drugs among multi-drug resistant tuberculosis cases in Shanghai, China].

OBJECTIVE: To determine the prevalence and risk factors on second-line drug resistance in patients with multidrug resistant tuberculosis (MDR-TB) in Shanghai, China. METHODS: All pulmonary TB patients with sputum culture positivity detected in Shanghai during January to December, 2009, were enrolled. All of the pretreatment sputum-positive cultures samples were tested for routine specimen identification and routine drug susceptibility testing for first-line drugs (Isoniazid, Rifampin, Ethambutol and Streptomycin). Drug susceptibility testing on second-line anti-TB drugs (Ofloxacin, Amikacin, Kanamycin, Capreomycin, P-aminosalicylic acid and Prothionamide) was routinely performed on isolates of Mycobacterium (M.) TB with MDR. Logistic regression analysis was conducted to determine the risk factors regarding second-line drug resistance. RESULTS: A total of 1867 patients infected with M. TB isolates were diagnosed at the TB hospitals/clinics in Shanghai during the study period, of whom 112 (6.0%) were MDR-TB, in which 58 cases (51.8%) showed resistant to at least one of the second-line drugs tested and 10 cases belonged to extensively drug-resistant. In the multivariate analyses, MDR-TB patients who were aged 45 - 59 years (aOR = 4.76, P = 0.001), with sputum smear positivity (aOR = 6.51, P = 0.026) were significantly more likely to show resistance to second-line drugs. CONCLUSION: The prevalence of second-line drug resistance among MDR-TB patients was high in Shanghai. MDR-TB patients who were under age of 45 - 59 years and with sputum smear positivity would represent important common risk factors for the resistance to second-line drugs.

Discriminatory potential of a novel set of Variable Number of Tandem Repeats for genotyping Mycobacterium marinum.

Mycobacterium marinum is a free-living bacterium that infects fish and amphibians, but is also an opportunistic pathogen in humans. Although in previous studies, the bacterium has shown a small number of Variable Number of Tandem Repeat (VNTR) polymorphic loci, the discriminatory power of the known VNTR loci is unlikely to be sufficient to distinguish such a globally ubiquitous waterborne microorganism, which has a presumably high genetic variance. The object of this study was to test M. marinum isolates from east China for strain diversity using previously described loci as well as novel VNTR loci, and to identify more discriminating VNTR loci that could enrich the genotyping tools for M. marinum. We found that 7 of the 12 tested VNTR loci, of which 5 were known loci and 2 loci were newly identified, showed good discriminatory power for the 14 M. marinum clinical isolates (Hunter-Gaston Index [HGI] value=0.990). The pathogenicity of isolates representing different VNTR clusters was also studied in a zebrafish (Danio rerio) infection model; in this model, 6 isolates representing 4 VNTR clusters induced chronic infections, whereas the American strain ATCC BAA-535 caused acute and lethal infections.

[Comparison of the proteome of Mycobacterium tuberculosis with Bovine mycobacterium by immuno-proteomic technology].

OBJECTIVE: To compare the proteome of Mycobacterium tuberculosis (MTB) H(37)Rv strain with Bovine mycobacterium (Bacillus Calmette-Guerin, BCG) strain at the sub-cellular level. METHODS: Proteins of the cell wall, membrane and cytolymph of H(37)Rv and BCG were extracted by density gradient centrifugation. Sub-cellular proteome of H(37)Rv and BCG were analyzed using 2-dimensional liquid chromatography. The immunity reactions of H(37)Rv fractions with sera from patients (n = 5) and healthy controls (n = 5), as well as BCG fractions with sera from healthy controls (n = 5) were analyzed by ELISA. Data was analyzed by t test. RESULTS: Twenty-six fractions of H(37)Rv were found to elicit specific antibody response. Fraction M3Fr18 of H(37)Rv reacted with sera from patients. The A(450) [(721 ± 3) × 10(-3)] was higher than that with sera from healthy controls [(356 ± 6) × 10(-3)], as well as the A(450) of the corresponding fractions of BCG with sera from healthy controls [(414 ± 7) × 10(-3)]. The differences between the patient group and the 2 healthy control groups were significant (t = 1.852 and 1.037, all P < 0.01). Moreover, fraction M10Fr21 of H(37)Rv reacted with sera from the patients. The A(450) [(954 ± 6) × 10(-3)] was higher than that with sera from the healthy controls [(415 ± 6) × 10(-3)], as well as the A(450) of the corresponding fractions of BCG with sera from the healthy controls [(315 ± 4) × 10(-3)]. The differences between the patient group and the 2 healthy control groups were significant (t = 2.113 and 2.550, all P < 0.01). CONCLUSIONS: The combination of 2-dimensional liquid chromatography and immunology technology is useful in finding antigens associated with MTB infection. Fractions M3Fr18 and M10Fr21 can elicit specific immune reaction among MTB patients, suggesting that they may be specific antigens of MTB infection.

Validity and reliability testing of the Chinese (mainland) version of the 39-item Parkinson's Disease Questionnaire (PDQ-39).

The 39-item Parkinson's Disease Questionnaire (PDQ-39) has been tested in many languages, but not in Chinese mainland. We aimed to assess the Chinese (mainland) version of the PDQ-39. Seventy-one subjects with Parkinson's disease (PD) completed the PDQ-39 and the Medical Outcomes Study 36-item Short Form Health Survey (SF-36). All subjects were retested with the PDQ-39 a week later. The united Parkinson's disease rating scale (UPDRS) and the Hoehn and Yahr (H & Y) scale were also used to evaluate the subjects. Reliability was assessed by Cronbach's alpha and intra-class correlation coefficient (ICC). Validity was examined in terms of agreement with SF-36, UPDRS, and H & Y scales. The Chinese (mainland) version of the PDQ-39 demonstrated acceptable reliability (Cronbach's alpha: 0.84-0.88; ICC: 0.56-0.82). The item-total correlations (0.33-0.88) and scaling success rates (77.56%) indicated satisfactory convergent and discriminant validity of the PDQ-39 items. The correlations between related constructs of the PDQ-39 and UPDRS (r=0.44-0.68) and between those of the PDQ-39 and SF-36 (r=(-0.46)-(-0.69)) were all statistically significant (P<0.01). Except for stigma, cognitions, and bodily discomfort, all other dimensions of the PDQ-39 significantly discriminated patients at different H & Y stages indicated by the H & Y scale. Although our observations indicate that some problematic subscales of this version of the PDQ-39 could be improved upon, this study suggests acceptable reliability and validity of the Chinese (mainland) version of the PDQ-39.

[Evaluation of the GenoType MTBDRplus assay for rifampin and isoniazid susceptibility testing of Mycobacterium tuberculosis].

OBJECTIVE: to evaluate the ability of GenoType MTBDRplus Assay for detection of rifampin (RFP) and isoniazid (INH) resistance in Mycobacterium tuberculosis. METHODS: seventy-five clinical isolates were tested for traditional drug susceptibility testing and GenoType MTBDRplus assay. The results were compared to assess the sensitivity and specificity of GenoType MTBDRplus assay. RESULTS: the sensitivity of GenoType MTBDRplus assays for detection of RFP and INH resistance were 98.0% and 86.5%, respectively. In pan-susceptible isolates of Mycobacterium tuberculosis, the specificity was 100% for both RFP resistance and INH resistance. CONCLUSION: with its high sensitivity and specificity, GenoType MTBDRplus assay is a promising rapid method to detect INH and RFP resistant Mycobacterium tuberculosis strains in Shanghai.

Selection of mutations to detect multidrug-resistant Mycobacterium tuberculosis strains in Shanghai, China.

Novel tools are urgently needed for the rapid, reliable detection of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains of Mycobacterium tuberculosis. To develop such tools, we need information about the frequency and distribution of the mycobacterial mutations and genotypes that are associated with phenotypic drug resistance. In a population-based study, we sequenced specific genes of M. tuberculosis that were associated with resistance to rifampin and isoniazid in 242 phenotypically MDR isolates and 50 phenotypically pan-susceptible isolates from tuberculosis (TB) cases in Shanghai, China. We estimated the sensitivity and specificity of the mutations, using the results of conventional, culture-based phenotypic drug susceptibility testing as the standard. We detected mutations within the 81-bp core region of rpoB in 96.3% of phenotypically MDR isolates. Mutations in two structural genes (katG and inhA) and two regulatory regions (the promoter of mabA-inhA and the intergenic region of oxyR-ahpC) were found in 89.3% of the MDR isolates. In total, 88.0% (213/242 strains) of the phenotypic MDR strains were confirmed by mutations in the sequenced regions. Mutations in embB306 were also considered a marker for MDR and significantly increased the sensitivity of the approach. Based on our findings, an approach that prospectively screens for mutations in 11 sites of the M. tuberculosis genome (rpoB531, rpoB526, rpoB516, rpoB533, and rpoB513, katG315, inhA-15, ahpC-10, ahpC-6, and ahpC-12, and embB306) could detect 86.8% of MDR strains in Shanghai. This study lays the foundation for the development of a rapid, reliable molecular genetic test to detect MDR strains of M. tuberculosis in China.

Deaths among tuberculosis cases in Shanghai, China: who is at risk?

BACKGROUND: Information about the risk factors associated with death caused by tuberculosis (TB) or death with TB would allow improvements in the clinical care of TB patients and save lives. The present study sought to identify characteristics associated with increased risk of death during anti-TB treatment in Shanghai, a city in China with one of the country's highest TB mortality rates. METHODS: We evaluated deaths among culture positive pulmonary TB cases that were diagnosed in Shanghai during 2000-2004 and initiated anti-TB therapy. Demographic, clinical, mycobacteriological information and treatment outcomes were routinely collected through a mandatory reporting system. RESULTS: There were 7,999 culture positive pulmonary cases reported during the study period. The overall case fatality rate was 5.5% (440 cases), and approximately half (50.5%) of the deaths were attributed to causes other than TB. Eighty-six percent of the deaths were among TB cases age > or = 60 years. The significant independent risk factors for mortality during anti-TB treatment were advancing age, male sex, sputum smear positivity, and the presence of a comorbidity. CONCLUSION: More vigorous clinical management and prevention strategies by both the TB control program and other public health programs are essential to improve TB treatment outcomes. Earlier suspicion, diagnosis and treatment of TB, especially among persons older than 60 years of age and those with a comorbid condition, could reduce deaths among TB patients.

Prevalence of fluoroquinolone resistance among tuberculosis patients in Shanghai, China.

We determined the prevalence of fluoroquinolone resistance among the isolates of Mycobacterium tuberculosis from 605 pulmonary tuberculosis patients in Shanghai, China. Mutations in gyrA were found in 81.5% of phenotypically fluoroquinolone-resistant isolates and were used as a molecular marker of fluoroquinolone resistance. gyrA mutations were detected in 1.9% of strains pan-susceptible to first-line drugs and 25.1% of multidrug-resistant strains. Fluoroquinolone resistance was independently associated with resistance to at least one first-line drug and prior tuberculosis treatment.

Transmission of MDR and XDR tuberculosis in Shanghai, China.

BACKGROUND: Multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) are global health problems. We sought to determine the characteristics, prevalence, and relative frequency of transmission of MDR and XDR TB in Shanghai, one of the largest cities in Asia. METHODS: TB is diagnosed in district TB hospitals in Shanghai, China. Drug susceptibility testing for first-line drugs was performed for all culture positive TB cases, and tests for second-line drugs were performed for MDR cases. VNTR-7 and VNTR-16 were used to genotype the strains, and prior treatment history and treatment outcomes were determined for each patient. RESULTS: There were 4,379 culture positive TB cases diagnosed with drug susceptibility test results available during March 2004 through November 2007. 247 (5.6%) were infected with a MDR strain of M. tuberculosis and 11 (6.3%) of the 175 MDR patients whose isolate was tested for susceptibility to second-line drugs, were XDR. More than half of the patients with MDR and XDR were newly diagnosed and had no prior history of TB treatment. Nearly 57% of the patients with MDR were successfully treated. DISCUSSION: Transmission of MDR and XDR strains is a serious problem in Shanghai. While a history of prior anti-TB treatment indicates which individuals may have acquired MDR or XDR TB, it does not accurately predict which TB patients have disease caused by transmission of MDR and XDR strains. Therefore, universal drug susceptibility testing is recommended for new and retreatment TB cases.

[Multiple infections of Mycobacterium tuberculosis in treated patients].

OBJECTIVE: To identify multiple infections of Mycobacterium tuberculosis in tuberculosis patients. METHODS: From the clinical isolates of M. tuberculosis during 1999 to 2004 stored at Shanghai Municipal Center for Disease Control and Prevention, cases who had two isolates with different drug resistance patterns in the same treatment episode were selected. The first isolate from the selected patients was inoculated onto Middlebrook 7H11 agar plates, and 30 single colonies from each isolate were picked and genotyped by the 7 loci Variable Number Tandem Repeat (VNTR) method. RESULTS: Two out of 22 isolates had two different genotypes among their 30 single colonies, and the proportions of the two genotype colonies were 24:6 and 29:1. The other 20 isolates showed identical genotype pattern among their 30 single colonies. CONCLUSION: Multiple infections of M. tuberculosis occurred in tuberculosis patients in Shanghai.

Mixed infections of Mycobacterium tuberculosis in tuberculosis patients in Shanghai, China.

We applied a 7 loci Variable-Number-Tandem-Repeats (VNTR-7) analysis method to identify mixed infections of Mycobacterium tuberculosis and to estimate the rate of mixed infections among pulmonary tuberculosis patients in Shanghai, China. We validated the VNTR-7 method and used it to genotype an isolate from each of the 249 from pulmonary tuberculosis patients reported from the Songjiang and Chongming districts in Shanghai during 2006. We identified 14 patients with mixed infections, and the estimated rate of mixed infections was 5.6% (14/249) (95% CI 3.1%-9.2%). Mixed infections were observed more frequently among tuberculosis patients undergoing retreatment (15.6%) than among new cases (4.1%) (p<0.05), and among tuberculosis patients whose disease was caused by non-Beijing genotype strains (12.5%) versus Beijing genotype strains (3.5%) (p<0.05). The VNTR-7 method is a highly sensitive, practical tool with relatively high discriminatory power, making it useful for studying mixed infections.

Highly polymorphic variable-number tandem repeats loci for differentiating Beijing genotype strains of Mycobacterium tuberculosis in Shanghai, China.

The PCR-based variable-number tandem repeats (VNTR) typing method is a very promising tool for the molecular epidemiological study of Mycobacterium tuberculosis. The discriminatory power of the VNTR loci that were optimized in many previous studies has not been evaluated in Shanghai, an area where Beijing genotype strains dominate. In the present study, we first performed a literature search to identify VNTR loci that were at least 45 bp in length. Second, we determined the Hunter-Gaston discriminatory index (HGI) values of each of the 45 VNTR loci that we identified, using Beijing genotype strains from a 'test set' of isolates from a population with low migration in Chongming Island, Shanghai, China. Third, we optimized two sets of VNTR loci, which we named VNTR-7 and VNTR-16. The HGI value of VNTR-7 was slightly lower than that of IS6110 restriction fragment length polymorphisms (RFLP), and the HGI values of VNTR-16 and IS6110 RFLP were comparable. Our results suggest that VNTR-7, followed by VNTR-16 and IS6110 RFLP, can be used routinely as a tool to discriminate between M. tuberculosis isolates in population-based epidemiologic studies of M. tuberculosis transmission in Shanghai, China.

[The prevalence and risk factors of drug-resistant tuberculosis among migratory population in Shanghai, China].

OBJECTIVE: To determine the prevalence of and risk factors for drug-resistant tuberculosis among migratory population in Shanghai. METHODS: All sputum culture positive patients among migratory population, confirmed at any district (county) tuberculosis dispensary in Shanghai from February 2004 to January 2005, were enrolled. The drug susceptibility test was performed by the proportion method. Univariate and multivariate analysis were performed to determine the risk factors associated with drug resistance. RESULTS: 493 patients were enrolled during the study period, among whom 431 patients had bacterial identification and drug susceptibility results. Of the 431 strains, 427 (99.1%) strains were Mycobacterium tuberculosis and 4 (0.9%) strains were Mycobacterium non-tuberculosis. The prevalence of drug-resistant tuberculosis among new cases and re-treatment cases was 16.0% (62/387) and 40.0% (16/40), respectively. The prevalence of MDR-tuberculosis among new cases and re-treatment cases was 4.1% (16/387) and 22.5% (9/40), respectively. A history of previous treatment for tuberculosis and age group of 45 - 60 years were significantly associated with drug resistance. CONCLUSION: The prevalence of drug-resistant tuberculosis among migratory population was relatively high in Shanghai, suggesting the necessity to strengthen the tuberculosis control program for migratory population.

Association between embB codon 306 mutations and drug resistance in Mycobacterium tuberculosis.

embB306 mutants were detected in both ethambutol (EMB)-resistant and EMB-susceptible strains of Mycobacterium tuberculosis. Multidrug-resistant (MDR) strains had a higher proportion of embB306 mutants than non-MDR strains (odds ratio, 6.78; P < 0.001). The embB306 locus is a candidate marker for rapid detection of MDR and extremely drug resistant tuberculosis.

Transmission of drug-resistant tuberculosis among treated patients in Shanghai, China.

We sought to determine whether patients who had therapy failure with increasingly drug-resistant strains of tuberculosis had primary or acquired drug resistance, by genotyping the initial and subsequent drug-resistant clinical isolates of Mycobacterium tuberculosis collected from patients by the Shanghai Centers for Disease Control and Prevention over the course of a 5-year period. The vast majority of patients (27/32) had primary drug resistance, indicating transmission of a drug-resistant strain of M. tuberculosis. Only 16% (5/32) had acquired drug resistance because of a poor treatment regimen or nonadherence to an adequate regimen. Our findings highlight the urgency of increasing efforts to interrupt the transmission of drug-resistant tuberculosis in communities and facilities in Shanghai, China.