BACKGROUND A common mechanism of resistance to beta-lactam antibiotics is the production of beta-lactamase by Gram-negative bacteria. Recently, nonderivative extended-spectrum beta-lactamases (ESBLs) from the TEM and SHV enzymes, such as CTX-M, that were related to different geographical regions have been recognized. OBJECTIVES The aim of this study was to determine the frequency of the CTX-M...

Ceftazidime was considerably more active than cefuroxime against 180 strains of resistant species of nosocomial gram-negative bacteria. In terms of antibacterial spectrum and intrinsic activity, ceftazidime is an improvement upon existing beta-lactam antibiotics in clinical use and can be regarded as a possible alternative to gentamicin.

Over the years, antibiotics have been among primary drugs used to treat or prevent infections in animals and humans. ESBL AmpC producing isolates become common microorganisms medical institutions. They contributed immensely clinical challenges caused by nosocomial with minimal therapeutic options.The present study investigated prevalence of extended-spectrum beta-lactamases Ambler class C Enugu...

AmpC β-lactamase confers resistance to β-lactam antibiotics in many Gram negative bacteria. Inducible expression of AmpC requires an N-acetylglucosaminidase termed NagZ. Here we describe the synthesis and characterization of hydroxyazepane inhibitors of NagZ. We find that these inhibitors enhance the susceptibility of clinically relevant Pseudomonas aeruginosa to β-lactams.

The aim of the present study was to test whether the combination of a beta-lactam drug plus an aminoglycoside has advantage over monotherapy for severe gram-negative infections. Of 2,124 patients with gram-negative bacteremia surveyed prospectively, 670 were given inappropriate empirical antibiotic treatment and the mortality rate in this group was 34%, whereas the mortality rate was 18% for 1,...

Sir: Ampicillin, carbenicillin and cephalosporins are beta-lactam antibiotics effective against some gram-negative bacteria. However, they may be neutralized by enzymes, usually beta-lactamases. Different betalactamases have been found among enterobacteria1^ Although ampicillin and carbenicillin are closely related, cross resistance does not always exist. The occurrence of a segregation in the ...

Cephalosporins are ┚lactam antibiotics. In cephalosporin C, four membered ┚lactam ring (which is mainly responsible for the activity) is fused with six membered dihydrothiazine ring to form the basic nucleus, 7-aminocephalosporanic acid (7-ACA) and to which ┙aminoadipic acid side chain is attached through an amide bond (Fig 1). (Mandell and Sande,1991)Although cephalosporin was found to be acti...

The widespread use of antibiotics has resulted in a growing problem of antimicrobial resistance in the community and hospital settings. Antimicrobial classes for which resistance has become a major problem include the β-lactams, the glycopeptides, and the fluoroquinolones. In gram-positive bacteria, β-lactam resistance most commonly results from expression of intrinsic low-affinity penicillin-b...