SYNOPSIS The effects of purified beta-lactamase from Bacillus cereus on the activity of four cephalosporins are described. Drug inactivation was measured spectrophotometrically and confirmed by microbiological assay and by microbiological techniques involving determinations of minimum inhibitory concentrations and growth curves of Staphylococcus aureus NCTC 6571 (Oxford) in broth containing dru...

Cefotiam was evaluated by a comparative open-label randomized trial with cephalothin in the therapy of skin and soft tissue infections in 39 patients. The most common organism isolated was Staphylococcus aureus (78%). We established evidence of primary infection with gram-negative bacilli in four patients, three of whom were diabetic. Eight patients had mixed infections or superinfections. No p...

Blood levels of cefazolin and cephalothin were determined in two separate crossover studies in 20 healthy male adults, each after intravenous and intramuscular administration. Pharmacokinetic parameters were calculated from the intravenous data based upon a two-compartment open model. The rate constants controlling the distribution between the central and peripheral compartments, the overall el...

The in vitro susceptibility of 155 strains of anaerobic bacteria to five cephalosporin antibiotics was tested. Cefoxitin was the most active against 33 isolates of Bacteroides fragilis; 82% of the strains were sensitive at 16 mug/ml. At 64 mug/ml cefazolin and cephaloridine were also generally effective. Cephalothin and cephalexin were relatively inactive versus B. fragilis. Cefoxitin, cephalor...

Filter paper discs were impregnated with a solution containing 20 mg of triphenyltetrazolium chloride per millilitre, and used in the typing of catalase-positive Campylobacter species. Also used were filter paper discs impregnated with cephalothin at 30 micrograms/ml, 60 micrograms/ml and 3 mg/ml and nalidixic acid at the same concentrations, as well as commercially available discs containing 3...

The ampicillin resistance of clinical isolates of Shigella sonnei is due to beta-lactamase production. Two kinds of resistance are found: low level, nontransmissible; and high level, tranmissible. The nontransmissible type of resistance results from a chromosomal mutation which increases the production of a beta-lactamase that hydrolyses cephalosporins relatively rapidly and gives cephalothin r...

The cross-reactivity of mouse anti-benzylpenicilloyl antibodies against cephalothin-haptens and cephalothin-polymers was divergent depending on the source and isotype of antibodies and the methods to raise them. High cross-reactivity nearly equal to the reactivity to homologous haptens and polymers was obtained only with the IgE antibody of C57BL/6J mouse raised shortly after an immunizing inje...

The bactericidal activity of five antibiotics for Legionella micdadei was determined by the construction of time-kill curves. Erythromycin, rifampin, penicillin G, cephalothin, and gentamicin were bactericidal for L. micdadei at readily achievable concentrations. The minimal bactericidal concentrations, defined as those producing 99.9% killing within 24 h, were: erythromycin, 4.6; rifampin, 0.1...

The rapid fixed-time assay for penicillinase was modified for measuring beta-lactamase activity with twelve substrates, i.e., benzylpenicillin, ampicillin, cloxacillin, methicillin, carbenicillin, cefazolin, cephalothin, cephaloglycin, cephalexin, cephalosporin C, 7-aminocephalosporanic acid, and cefoxitin. The method depends upon the reduction of iodine by the hydrolyzed substrate. Determined ...