Chen J.,Huazhong University of Science and Technology |
Chen J.,Wuhan Tuberculosis Prevention and Treatment Center |
Chen Z.,Wuhan Tuberculosis Prevention and Treatment Center |
Li Y.,Huazhong University of Science and Technology |
And 6 more authors.
Brazilian Journal of Infectious Diseases
Objective: The study aimed to investigate gyrA and gyrB mutations in Mycobacterium tuberculosis (MTB) clinical strains from 93 patients with pulmonary tuberculosis in Hubei Province, China and analyze the association between mutation patterns of the genes and ofloxacin resistance level. Results: Among 93 MTB clinical isolates, 61 were ofloxacin-resistant by the proportion method, and 32 were ofloxacin-susceptible MDR-TB. No mutation in the gyrB gene was found in any MTB strains. In the 61 ofloxacin-resistant isolates, 54 mutations were observed in the gyrA gene. Only one mutation in the gyrA gene was found in ofloxacin-susceptible MDR-TB isolates. In this study, the mutation patterns of gyrA involved seven patterns of single codon mutation (A90 V, S91P, S91T, D94N, D94Y, D94G or D94A) and two patterns of double codons mutation (S91P & D94H, S91P & D94A). The ofloxacin minimal inhibitory concentrations (MICs) of three patterns of single codon mutations in the gyrA gene (codons 94, 90 and 91) showed a statistically significant difference (p < 0.0001). Conclusions: The gyrA mutations at codons 90, 91 and 94 constitute the primary mechanism of fluoroquinolone resistance in MTB, and mutations at codon 91 in the gyrA gene may be associated with low-level resistance to ofloxacin. © 2012 Elsevier Editora Ltda. All rights reserved. Source
Chena Z.,Wuhan Tuberculosis Prevention and Treatment Center |
Chena Z.,Huazhong University of Science and Technology |
Wanga W.,Wuhan Tuberculosis Prevention and Treatment Center |
Wanga W.,Huazhong University of Science and Technology |
And 6 more authors.
International Journal of Applied Research in Veterinary Medicine
Detection of Mycobacterium bovis (M bovis) is important for prevention of a cattle tuberculosis outbreak. In this study, a nanobio-sensor modifed by gold nanoparticles for detection of M bovis in milk was developed. The biosensor was fabricated frstly by dropping the mix solution of chitosan (Ch), Au nanoparticles (AuNPs), and alkaline phosphatase labeled goat anti-mouse IgG (ALP-IgG) on glassy carbon electrode (GCE) to form a robust flm with good bio-compatibility, then antibody against Myco-bacterium tuberculosis (anti-M.TB), which could identify M bovis, was immobilized on the composite flm through the reaction with ALP-IgG. The biosensor was able to detect M bovis with the detection limit 3.5×103 cfu/ml and a linear range from 104 to 106 cfu/ml. This strategy could be applied as a rapid platform for detection of M. bovis for cattle tuberculosis infection. © 2015 Veterinary Solutions LLC. All rights reserved. Source