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Brandon Eilertson Fernanda Maruri Amondrea Blackman Miguel Herrera David C. Samuels Timothy R. Sterling 《Antimicrobial agents and chemotherapy》2014,58(6):3270-3275
Heteroresistance is the coexistence of populations with differing nucleotides at a drug resistance locus within a sample of organisms. Although Sanger sequencing is the gold standard for sequencing, it may be less sensitive than deep sequencing for detecting fluoroquinolone heteroresistance in Mycobacterium tuberculosis. Twenty-seven fluoroquinolone monoresistant and 11 fluoroquinolone-susceptible M. tuberculosis isolates were analyzed by Sanger and Illumina deep sequencing. Individual sequencing reads were analyzed to detect heteroresistance in the gyrA and gyrB genes. Heteroresistance to fluoroquinolones was identified in 10/26 (38%) phenotypically fluoroquinolone-resistant samples and 0/11 (P = 0.02) fluoroquinolone-susceptible controls. One resistant sample was excluded because of contamination with the laboratory strain M. tuberculosis H37Rv. Sanger sequencing revealed resistance-conferring mutations in 15 isolates, while deep sequencing revealed mutations in 20 isolates. Isolates with fluoroquinolone resistance-conferring mutations by Sanger sequencing all had at least those same mutations identified by deep sequencing. By deep sequencing, 10 isolates had a single fixed (defined as >95% frequency) mutation, while 10 were heteroresistant, 5 of which had a single unfixed (defined as <95% frequency) mutation and 5 had multiple unfixed mutations. Illumina deep sequencing identified a higher proportion of fluoroquinolone-resistant M. tuberculosis isolates with heteroresistance than did Sanger sequencing. The heteroresistant isolates frequently demonstrated multiple mutations, but resistant isolates with fixed mutations each had only a single mutation. 相似文献
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Fernanda Herrera Costa DDS MSc Victor Costa DDS MSc Jorge Esquiche León DDS PhD Ana Lia Anbinder DDS PhD Alfredo Ribeiro-Silva MD PhD Estela Kaminagakura DDS PhD 《Pediatric dermatology》2020,37(4):721-723
We report a case of atypical oral hairy leukoplakia (OHL) in a 9-year-old immunocompetent girl treated with fluticasone propionate nasal spray for allergic rhinitis. The OHL in childhood is uncommon and should be included in a differential diagnosis of white lesions in the oral mucosa. 相似文献
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Levels of serum retinol‐binding protein 4 before and after non‐surgical periodontal treatment in lean and obese subjects: An interventional study
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Association of Guideline‐concordant Acute Asthma Care in the Emergency Department With Shorter Hospital Length of Stay: A Multicenter Observational Study
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