Publications by authors named "Tong-Yang Xiao"
Article Synopsis
- * Researchers analyzed 146 isolates, identifying various mutations and assessing their impact on EMB resistance through minimum inhibitory concentration testing and statistical modeling.
- * Results showed that certain mutations (Met306Val, Met306Ile, Gly406Ala, and Gln497Arg) were significantly related to EMB resistance, with some mutations strongly correlating with high-level resistance, highlighting the complex genetic factors influencing EMB susceptibility.
Mutations are Associated with Variable Levels of Rifampin and Rifabutin Resistance in .
Infect Drug Resist
November 2022
Article Synopsis
- The study aimed to investigate how specific genetic mutations relate to resistance against the antibiotics rifampin (RIF) and rifabutin (RFB) in bacteria.
- Researchers analyzed 177 clinical isolates, identifying multiple mutations and their impact on the minimum inhibitory concentrations (MICs) for RIF and RFB.
- The findings revealed distinct mutation patterns linked to high-level resistance, underscoring the complexity of rifamycin resistance and its implications for tuberculosis treatment options.*
Article Synopsis
- - The study aimed to explore mutations in the RpoB gene and their role in developing resistance to rifampin (RIF), using structural analysis.
- - Researchers sequenced the RpoB gene in 175 tuberculosis isolates and identified 34 mutations across 17 sites; many of these mutations impact the interaction between RpoB and RIF.
- - Key mutations like S450L and H445D were linked to high-level RIF resistance, offering insights that could inform the creation of new antibiotics and diagnostic methods for tuberculosis.
Article Synopsis
- - The study examined drug-resistant tuberculosis (TB) in 189 patients at a Chinese TB hospital, focusing on the prevalence, risks, and genetic factors associated with the disease.
- - Results showed that 28.6% of the isolates were resistant to at least one anti-TB drug, with 9.5% classified as multidrug-resistant and 1.1% as extensively drug-resistant, particularly affecting rural and previously treated patients.
- - Genetic analysis revealed that 58.7% of the isolates were Beijing genotype strains, with specific mutations identified, but no clear link between genotype and drug resistance was found.
Beijing genotype of Mycobacterium tuberculosis is less associated with drug resistance in south China.
Int J Antimicrob Agents
December 2019
Article Synopsis
- * Results showed that 34.8% of the isolates were resistant to at least one of seven tested drugs, with multidrug-resistant and extensively drug-resistant tuberculosis rates at 17.0% and 1.4%, respectively.
- * Although drug resistance was more common in Beijing genotype strains, the study found no significant difference in drug resistance between the Beijing and non-Beijing genotypes, particularly among previously treated patients.
Article Synopsis
- This study investigated the potential of a new Mycobacterium tuberculosis antigen called Rv0674 for diagnosing and vaccinating against tuberculosis (TB).* -
- Results showed that TB patients had a stronger immune response (higher IgG levels) to Rv0674 compared to healthy controls, with decent sensitivity (77.1%) and specificity (81.1%) in serological tests.* -
- The research suggests Rv0674 could be a promising candidate for a TB diagnosis tool and vaccine, as it activates important immune responses in test subjects.*
Article Synopsis
- The study aimed to better understand macrolide susceptibility and resistance mechanisms in non-tuberculous mycobacteria (NTM) in China for improved infection treatment.
- Testing involved 310 clinical NTM isolates with four macrolides, revealing varied resistance patterns, particularly showing M. abscessus subsp. massiliense was mostly susceptible while M. fortuitum was highly resistant.
- Key resistance mutations were identified, but known mechanisms (23S rRNA and erm) did not explain all resistance cases, suggesting further research is needed to uncover additional resistance factors in different NTM species.
Article Synopsis
- The study focuses on the EmbCAB proteins and their link to ethambutol (EMB) resistance in Mycobacterium tuberculosis from China, noting that mutations in these proteins contribute to resistance.
- Researchers sequenced 125 isolates and tested their sensitivity to EMB by assessing growth across 10 concentrations, discovering that 82.6% of EMB-resistant strains had at least one mutation in the studied region.
- The findings indicate that specific and multiple mutations significantly influence EMB resistance levels, with a notable association between high-level resistance and the presence of multiple mutations.
Article Synopsis
- Rapid detection of second-line drug resistance in multi-drug tuberculosis (MDR-TB) is crucial for timely treatment initiation.
- This study utilized multiplex allele-specific PCR (MAS-PCR) to identify specific mutations linked to resistance against the drugs ofloxacin (OFX) and kanamycin (KAN) in 139 MDR-TB isolates from China.
- MAS-PCR showed sensitivities of 67.3% for OFX and 76.5% for KAN, with 100% specificity, indicating it as a reliable method for quick identification of drug resistance in MDR-TB patients.
Article Synopsis
- Genotyping and DNA sequencing of 235 M. tuberculosis isolates from China revealed specific mutations in the lysX gene that serve as markers for Beijing and modern Beijing strains.
- These findings were supported by analysis of 24 additional M. tuberculosis genomes from various countries.
- A new, efficient multiplex allele-specific PCR method was developed to quickly detect these mutations in lysX, successfully identifying all Beijing and modern Beijing strains in the tested samples.
Identification of mutations conferring streptomycin resistance in multidrug-resistant tuberculosis of China.
Diagn Microbiol Infect Dis
October 2015
Article Synopsis
- - We studied mutations in 140 multidrug-resistant tuberculosis (MDR-TB) strains from China, focusing on three genes: rpsL, rrs, and gidB, and found that 65.7% were resistant to streptomycin (STR), mainly from the Beijing strain.
- - The study showed a strong correlation between STR resistance and the Beijing family of tuberculosis (P=0.00) and highlighted that specific mutations in rpsL and rrs were common in STR-resistant isolates.
- - Detecting mutations in these genes had high effectiveness, with 94.6% sensitivity and 91.7% specificity, making them reliable indicators for STR resistance, which could aid the development of rapid
Article Synopsis
- * A study of 139 MDR-TB isolates in China revealed that 56.8% were resistant to EMB, with a significant portion (82.2%) belonging to the Beijing family, and that 79.1% of isolates had mutations in the embCAB operon.
- * The most frequent mutations were found in the embB gene, especially at codon 306, which closely correlated with EMB resistance; however, using embB306-497 DNA sequencing for detection was highly sensitive but only moderately