INTRODUCTION This study investigated the mechanisms of resistance in 36 E. coli isolated from waste, litter, soil and water samples collected from poultry farms in Southwestern Nigeria. METHODOLOGY Minimum inhibitory concentration (MIC) distributions of the isolates were determined using the methods of the Clinical and Laboratory Standard Institute and resistance genes detected by PCR. RESU...

OBJECTIVES The aim of this study was to determine the spread of plasmid-mediated quinolone resistance determinants [qnr-like, aac(6')-Ib-cr and qepA genes] among nalidixic acid-resistant enterobacterial strains isolated from outpatients from Southeast Brazil, their transferability and the genetic structures associated with the qnr genes. METHODS The qnrA, qnrB and qnrS genes were screened by ...

One hundred fifty AAC(6')-Ib-positive gram-negative isolates collected between 1981 and 1991 were examined by PCR for the presence of the aac(6')-Ib-cr variant and other plasmid-mediated quinolone resistance (PMQR) genes. None had the aac(6')-Ib-cr variant, qnrA, qnrS, qnrC, or qepA, but two strains collected in 1988 had qnrB alleles, making these the earliest known PMQR genes.

Background and Aims: Extended-spectrum β-lactamase (ESBL) producing gram negative bacteria are resistant to penicillins, narrow and extended-spectrum cephalosporins, and aztreonam; also they are frequently resistant to trimethoprim-sulfamethoxazole, aminoglycosides, and quinolones. This study aimed to investigate the prevalence of plasmid-mediated quinolone resistance (PMQR) determinants q...

With regard to antibiotic resistance studies in various model animals in the urban environment, the presented study focused on the rook, many behavioural and ecological aspects of which are important from an epidemiological point of view. A total of 130 Escherichia coli strains isolated from rook faeces during a two-year period (2011-2012) were investigated for antibiotic resistance and virulen...

OBJECTIVES Escherichia coli is regarded as the most important etiological agent of urinary tract infections. Fluoroquinolones are routinely used in the treatment of these infections; however, in recent years, a growing rate of resistance to these drugs has been reported globally. The aims of this study were to detect plasmid-mediated qnrA, qnrB, and qnrS genes among the quinolone-nonsusceptible...

INTRODUCTION Although independently acquired, plasmid-mediated quinolone resistance appears to be linked with extended-spectrum or AmpC-type beta-lactamases. Since no data are available in African countries, the prevalence of qnr genes at the University Hospital Ibn Rochd, Casablanca, Morocco, was investigated. METHODOLOGY Between October 2006 and March 2007, the following 39 randomly selecte...

A total of 514 consecutive clinical Escherichia coli isolates, irrespective of resistance background, were collected in the period 2002-2008 in Wenzhou, southern China, to investigate the prevalence of plasmid-mediated quinolone resistance (PMQR). The dominant PMQR gene was aac(6')-Ib-cr, followed by qnr, whereas qepA was absent. A total of 253 (49.2%) of these isolates were aac(6')-Ib-positive...

Background and Objectives Since the fluoroquinolones are the broad-spectrum antibiotics, they affect both Gram-negative and Gram-positive bacteria. These antibiotics are widely prescribed by physicians. As a result, some bacteria, especially Enterobacteriaceae, have shown a resistance to this family of antibiotics. The current study aimed at detecting the frequency of qnrA, qnrB, and qnrS genes...