Ertapenem, imipenem, meropenem, ceftriaxone, piperacillin, piperacillin-tazobactam, clindamycin, and metronidazole were agar dilution MIC tested against 431 anaerobes. Imipenem, meropenem, and ertapenem were the most active beta-lactams (MICs at which 50% of the strains are inhibited [MIC(50)s], 0.125 to 0.25 microg/ml; MIC(90)s, 1.0 to 2.0 microg/ml). Time-kill studies revealed that ertapenem ...

Acquired resistance is through the production of AmpC Beta Lactamases (AmpC), Extended Spectrum Beta Lactamases (ESBL) and Metallo Beta-Lactamases Enzymes (MBL). Resistance to β-lactam antibiotics is associated with production of ESBL which can hydrolyze oxyimino β-lactams such as cefotaxime, ceftriaxone, ceftazidime and monobactams, however, without any effect on cephamycins, carbapenems and r...

cis-3-Acetoxy-4-(3-aryloxiran-2-yl)azetidin-2-ones were prepared through a Staudinger [2+2]-cyclocondensation between acetoxyketene and the appropriate epoxyimines in a highly diastereoselective way. Subsequent potassium carbonate-mediated acetate hydrolysis, followed by intramolecular ring closure through epoxide ring opening, afforded stereodefined 3-aryl-4-hydroxy-2-oxa-6-azabicyclo[3.2.0]he...

MICs of 21 beta-lactams were determined by agar dilution against 283 penicillin-susceptible (pen-S), 122 intermediate (pen-I) and 23 fully penicillin-resistant (pen-R) pneumococci. MICs of all beta-lactams increased with increasing MICs of penicillin. Clometocillin was the most active penicillin against pen-I or pen-R pneumococci. All oral cephalosporins except cefuroxime and cefpodoxime were l...

We report a multidrug-resistant strain of Leclercia adecarboxylata responsible for catheter-related bacteremia in a 47-year-old female with breast cancer. The isolated strain was resistant to several β-lactams, aminoglycosides, and folate pathway inhibitors and harbored bla(TEM-1) and bla(CTX-M) group 1 and intl1 genes (dfrA12-orfF-aadA2) as genetic determinants for resistance. Based on a revie...