Objectives: WGS and phenotypic methods were used to determine the prevalence of azithromycin resistance in Salmonella enterica isolates from the UK and to identify the underlying mechanisms of resistance.
Methods: WGS by Illumina HiSeq was carried out on 683 Salmonella spp. isolates.
The advent of a miniaturized DNA sequencing device with a high-throughput contextual sequencing capability embodies the next generation of large scale sequencing tools. The MinION™ Access Programme (MAP) was initiated by Oxford Nanopore Technologies™ in April 2014, giving public access to their USB-attached miniature sequencing device. The MinION Analysis and Reference Consortium (MARC) was formed by a subset of MAP participants, with the aim of evaluating and providing standard protocols and reference data to the community.
View Article and Find Full Text PDFBloodstream infection (BSI) by microorganisms can lead to sepsis. This condition has a high mortality rate, which rises significantly with delays in initiation of appropriate antimicrobial treatment. Current culture methods for diagnosing BSI have long turnaround times and poor clinical sensitivity.
View Article and Find Full Text PDFShort-read, high-throughput sequencing technology cannot identify the chromosomal position of repetitive insertion sequences that typically flank horizontally acquired genes such as bacterial virulence genes and antibiotic resistance genes. The MinION nanopore sequencer can produce long sequencing reads on a device similar in size to a USB memory stick. Here we apply a MinION sequencer to resolve the structure and chromosomal insertion site of a composite antibiotic resistance island in Salmonella Typhi Haplotype 58.
View Article and Find Full Text PDFBackground: Recurrence of tuberculosis after treatment makes management difficult and is a key factor for determining treatment efficacy. Two processes can cause recurrence: relapse of the primary infection or re-infection with an exogenous strain. Although re-infection can and does occur, its importance to tuberculosis epidemiology and its biological basis is still debated.
View Article and Find Full Text PDFObjectives: Lead antituberculosis (anti-TB) molecules with novel mechanisms of action are urgently required to fuel the anti-TB drug discovery pipeline. The aim of this study was to validate the use of the high-throughput spot culture growth inhibition (HT-SPOTi) assay for screening libraries of compounds against Mycobacterium tuberculosis and to study the inhibitory effect of ibuprofen (IBP) and the other 2-arylpropanoic acids on the growth inhibition of M tuberculosis and other mycobacterial species.
Methods: The HT-SPOTi method was validated not only with known drugs but also with a library of 47 confirmed anti-TB active compounds published in the ChEMBL database.
In Tanzania sputum culture for tuberculosis (TB) is resource intensive and available only at zonal facilities. In this study overnight pooled sputum collection technique was compared with standard spot morning collection among pulmonary TB suspects at Kibong'oto National TB Hospital in Tanzania. A spot sputum specimen performed at enrollment, an overnight pooled sputum, and single morning specimen were collected from 50 subjects and analyzed for quality, quantity, and time to detection in Bactec MGIT system.
View Article and Find Full Text PDFAntimicrob Agents Chemother
December 2011
Low antituberculosis (TB) drug levels are common, but their clinical significance remains unclear, and methods of measurement are resource intensive. Subjects initiating treatment for sputum smear-positive pulmonary TB were enrolled from Kibong'oto National TB Hospital, Tanzania, and levels of isoniazid, rifampin, ethambutol, and pyrazinamide were measured at the time of typical peak plasma concentration (C(2 h)). To evaluate the significance of the effect of observed drug levels on Mycobacterium tuberculosis growth, a plasma TB drug activity (TDA) assay was developed using the Bactec MGIT system.
View Article and Find Full Text PDFObjectives: Fluoroquinolones are used in second-line treatment of tuberculosis (TB) and have a potential role in shortening TB treatment duration. The wide use of fluoroquinolones in the treatment of other infections, including respiratory tract infections in patients with (undiagnosed) active TB, could result in fluoroquinolone-resistant Mycobacterium tuberculosis. We determined the rate of fluoroquinolone resistance in M.
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