background :  pathogenic bacteria because of beta-lactam antibiotic resistance genes are dangerous to society. this resistance due to esbl genes, plasmids and transposons that by receiving or mutation occurs. the most important factor beta-lactam antibiotic resistance is beta lactamase enzymes. the purpose of this study was to evaluate the frequency of hospital opportunistic pathogenic bacteria...

The purpose of this study was to investigate the presence of beta-lactam-resistant bacteria in six different types of Portuguese cheese. The numbers of ampicillin resistant (AMP(r)) bacteria varied from 4.7 x 10(2) to 1.5 x 10(7) CFU/g. Within 172 randomly selected beta-lactam-resistant bacteria, 44 resistant phenotypes were found and 31.4% were multidrug resistant. The majority (85%) of the is...

The in vitro antibacterial activity of four beta-lactam antibiotics (cefatrizine [BL-S640], cefamandole, cefoxitin, and carbenicillin) and three aminoglycosides (amikacin, gentamicin, and tobramycin) was determined against 197 strains of cephalothin-resistant Enterobacteriaceae. Eighty strains were found to be gentamicin-sensitive, and 117 were found to be gentamicin-resistant. Carbenicillin wa...

Article history: Received on: 27/07/2016 Revised on: 24/08/2016 Accepted on: 30/09/2016 Available online: 28/12/2016 Beta lactam antibiotics are one of the most commonly prescribed antibiotic drug classes in medical practice. Cephalosporins differ from other beta lactam antibiotics in both their structure and spectrum of action. Beta lactam antibiotics, in general, may cause platelet deficiency...

A mouse model of intestinal colonization with vancomycin-resistant enterococci (VRE) was used to study the effect of different beta-lactam antibiotics on establishment of VRE colonization. A clinical VanB VRE isolate, Enterococcus faecium C68 (102 or 104 cfu), was inoculated by gastric gavage in conjunction with subcutaneous administration of antibiotics. The MIC of ceftriaxone and ticarcillin ...

We performed a prospective study of all inpatient and outpatient methicillin-resistant Staphylococcus aureus (MRSA) isolates identified at the University of Chicago Hospitals from November 2003 through November 2004. Differences in resistance to non-beta-lactam antimicrobial drugs were determined after stratification of the 578 MRSA isolates into 4 groups by patient age (pediatric vs. adult) an...

A rapid and specific high-performance liquid chromatography method with UV detection (HPLC-UV) for the simultaneous determination of 12 beta-lactam antibiotics (amoxicillin, cefepime, cefotaxime, ceftazidime, ceftriaxone, cloxacillin, imipenem, meropenem, oxacillin, penicillin G, piperacillin, and ticarcillin) in small samples of human plasma is described. Extraction consisted of protein precip...

Effects of several beta-lactam antibiotics on the acetaldehyde-metabolizing system were studied using germ-free rats. Administration of cefamandole (CMD) to the rats caused a decrease in liver mitochondrial low Km aldehyde dehydrogenase activity and an increase in blood acetaldehyde level during ethanol metabolism, similar to the case in conventional rats. Oral administration of CMD produced a ...

BACKGROUND Beta-lactamase production and porin decrease are the well-recognized mechanisms of acquired beta-lactam resistance in Klebsiella pneumoniae isolates. However, such mechanisms proved to be absent in K. pneumoniae isolates that are non susceptible to cefoxitin (FOX) and susceptible to amoxicillin+clavulanic acid in our hospital. Assessing the role of efflux pumps in this beta-lactam ph...

Using clinical strains of Serratia marcescens with low and high resistance to extended-spectrum beta-lactam antibiotics, the relative contribution of chromosomal beta-lactamase and defective outer membrane porins to resistance was determined. Low-level resistance was caused by overproduced beta-lactamase alone. High-level resistance was due to beta-lactamase overproduction and defects of porin ...