scholarly journals Genotypic Diversity of Ciprofloxacin Nonsusceptibility and Its Relationship with Minimum Inhibitory Concentrations in Nontyphoidal Salmonella Clinical Isolates in Taiwan

Antibiotics ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1383
Author(s):  
Shiuh-Bin Fang ◽  
Tsai-Ling Yang Lauderdale ◽  
Chih-Hung Huang ◽  
Pei-Ru Chang ◽  
Yuan-Hung Wang ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genotypic Diversity ◽  
Quinolone Resistance ◽  
Clinical Isolates ◽  
Chain Reactions ◽  
Polymerase Chain Reactions ◽  
Minimum Inhibitory Concentrations ◽  
Polymerase Chain ◽  
Chromosomal Mutations ◽  
The Relationship

This study analyzed the genetic diversity of ciprofloxacin (CIP) nonsusceptibility and the relationship between two major mechanisms and minimum inhibitory concentrations (MICs) of CIP in nontyphoidal Salmonella (NTS). Chromosomal mutations in quinolone resistance-determining regions (QRDRs) and plasmid-mediated quinolone resistance (PMQR) genes were searched from ResFinder, ARG-ANNOT, and PubMed for designing the sequencing regions in gyrA, gyrB, parC, and parE, and the 13 polymerase chain reactions for PMQR genes. We found that QRDR mutations were detected in gyrA (82.1%), parC (59.0%), and parE (20.5%) but not in gyrB among the 39 isolates. Five of the 13 PMQR genes were identified, including oqxA (28.2%), oqxB (28.2%), qnrS (18.0%), aac(6′)-Ib-cr (10.3%), and qnrB (5.1%), which correlated with the MICs of CIP within 0.25–2 μg/mL, and it was found that oxqAB contributed more than qnr genes to increase the MICs. All the isolates contained either QRDR mutations (53.8%), PMQR genes (15.4%), or both (30.8%). QRDR mutations (84.6%) were more commonly detected than PMQR genes (46.2%). QRDR mutation numbers were significantly associated with MICs (p < 0.001). Double mutations in gyrA and parC determined high CIP resistance (MICs ≥ 4 μg/mL). PMQR genes contributed to intermediate to low CIP resistance (MICs 0.25–2 μg/mL), thus providing insights into mechanisms underlying CIP resistance.

scholarly journals Detection of Mycobacterium tuberculosis complex and non-tuberculous mycobacteria by multiplex polymerase chain reactions

1999 ◽  
Vol 5 (1) ◽  
pp. 61-70
Author(s):  
A. S. Mustafa
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Mycobacterium Tuberculosis Complex ◽  
Clinical Isolates ◽  
Tuberculosis Complex ◽  
Clinical Specimens ◽  
Chain Reactions ◽  
Polymerase Chain Reactions ◽  
Polymerase Chain

The ability of two-band and three-band multiplex polymerase chain reactions to detect and differentiate Mycobacterium tuberculosis complex from non-tuberculous mycobacteria was evaluated. The polymerase chain reactions differentiated between M. tuberculosis and non-tuberculous mycobacteria when standard strains and clinical isolates of mycobacteria were tested. The sensitivity of the two-band and three-band techniques to detect M. tuberculosis in clinical specimens, compared with smear and/or culture, was 88% and 75% respectively. Although both techniques showed 100% specificity, the superior sensitivity of the two-band technique suggests that it could be more useful in the diagnosis of tuberculosis and in differentiating M. tuberculosis complex from non-tuberculous mycobacteria

Assessment of genetic diversity of Mithun (Bos frontalis) population in Bhutan using microsatellite DNA markers

2016 ◽  
Vol 59 ◽  
pp. 1-6 ◽  
Author(s):  
Sangay Tenzin ◽  
Jigme Dorji ◽  
Tashi Dorji ◽  
Yoshi Kawamoto
Keyword(s):  
Genetic Diversity ◽  
Genetic Bottleneck ◽  
Chain Reactions ◽  
Mode Shift ◽  
Low Level ◽  
Polymerase Chain Reactions ◽  
Expected Heterozygosity ◽  
Hair Samples ◽  
Microsatellite Dna Markers ◽  
Polymerase Chain

Summary Genetic diversity of Mithun population in Bhutan was studied using 14 microsatellite markers. Two sets of two-step polymerase chain reactions were performed with multiplex and individual markers for genotyping 105 hair samples collected from Arong in Samdrupjongkhar (AS, 36) and Wangdigang in Zhemgang (WZ, 69). Fifty-three alleles were detected with average of 3.89 alleles and polymorphism information content of 0.44 ± 0.03 per locus. A low level of genetic variability within population was present with observed heterozygosity at 0.50 ± 0.06 and expected heterozygosity at 0.48 ± 0.06. Analysis of molecular variance attributed 58 percent of total variation to within the individuals. Mean F IS and F IT were −0.056 and 0.005 respectively, indicated low level of population differentiation and limited out-breeding. The normal L-shaped distribution of allelic frequencies without any mode-shift revealed the absence of recent genetic bottleneck in Mithun populations. Therefore to manage inbreeding in the small Mithun population of Bhutan, periodic assessment of inbreeding levels and exchange of animals between farms is recommended to reduce frequency of introduction of animals from India.

scholarly journals Investigation of Lethal Concurrent Outbreak of Chlamydiosis and Pigeon Circovirus in a Zoo

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1654
Author(s):  
Wei-Tao Chen ◽  
Chin-Ann Teng ◽  
Cheng-Hsin Shih ◽  
Wei-Hsiang Huang ◽  
Yi-Fan Jiang ◽  
...  
Keyword(s):  
Disease Outbreaks ◽  
Chlamydia Psittaci ◽  
Bursa Of Fabricius ◽  
Chain Reactions ◽  
Renal Epithelium ◽  
Polymerase Chain Reactions ◽  
Transmission Electron ◽  
Intracytoplasmic Inclusion Bodies ◽  
Polymerase Chain ◽  
Streptopelia Orientalis

During the spring, an outbreak of sudden death involving 58 birds occurred in a zoo. Histopathological examinations revealed variable numbers of intracytoplasmic basophilic microorganisms in the macrophages, hepatocytes, and renal epithelium of most birds, along with occasional botryoid intracytoplasmic inclusion bodies within histiocytes in the bursa of Fabricius. Based on the results of histopathological examinations, immunohistochemical staining, transmission electron microscopy, and polymerase chain reactions, genotype B Chlamydia psittaci infection concurrent with pigeon circovirus (PiCV) was diagnosed. A retrospective survey, including two years before the outbreak and the outbreak year, of C. psittaci and PiCV infections of dead birds in the aviaries, revealed that the outbreak was an independent episode. The findings of this study indicate that concurrent infection with C. psittaci and PiCV might lead to lethal outbreaks of chlamydiosis, particularly Streptopelia orientalis. In addition, persistently monitoring both pathogens and identifying potential PiCV carriers or transmitters might also help prevent lethal disease outbreaks.

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