Let Qnr be the graph with vertex set {?1,1}n in which two vertices are joined if their Hamming distance is at most r. The edge-isoperimetric problem for that: For every (n,r,M) such that 1?r?n and 1?M?2n, determine minimum edge-boundary size of a subset given M. In this paper, we apply different approaches to prove bounds problem. first approach linear programming second probabilistic. Our boun...

Multi-antibiotic-resistant Gram-negative pathogens are becoming more prevalent and an association exists between chromosomally conferred fluoroquinolone resistance and the presence of plasmid-borne resistances, such as extended spectrum beta-lactamases. This link is not wholly explained by strain spread or the presence of fluoroquinolone-modifying enzymes. Plasmid-encoded toxin-antitoxin addict...

INTRODUCTION Rapid dissemination of plasmid-mediated quinolone resistance (PMQR) has been reported in clinical isolates. METHODOLOGY A total of 149 clinical isolates of Enterobacteriaceae were collected in Beijing and screened for PMQR genes using polymerase chain reaction (PCR). Real-time quantitative PCR was used to study the expression of qnrS. RESULTS The rates of qnr and aac(6')-Ib-cr ...

The study set out to look at the clinical strain of A. faecalis's antibiotic susceptibility pattern. Both biochemical and molecular approaches were used identify A.faecalis. VITEK compact system was analyze strain's profile. use PCR evaluated determine presence resistance genes. It also determined whether determinants could be transferred. that feacalis showed imipenem, cefepime, ceftazidime, g...

Resistance to quinolones in Gram-negative bacteria is usually mediated by the following: (i) chromosomal mutations that alter the target enzymes, DNA gyrase and topoisomerase IV, in their quinolone resistance-determining regions (QRDR), (ii) changes in drug entry (loss of porin channels), and (iii) the presence of plasmid-mediated quinolone resistance (PMQR) determinants [qnrA, qnrB, qnrS, qnrC...