A comparison was made of the in vitro activities of norfloxacin and of nine other orally administered antibacterial agents against 180 clinical isolates representing the bacterial species most frequently implicated in infections of the gastrointestinal tract in humans. The 90% minimal inhibitory concentrations showed norfloxacin to be 4, 15, 4, 17, 17, 17, and 33 times more active than the next...

The minimal bactericidal concentrations of N-formimidoyl thienamycin (N-f-thienamycin) against 21 strains of enterococci isolated from patients with infective endocarditis were determined by macro- and microdilution methods. By a macrodilution technique with the minimal bactericidal concentration defined as greater than or equal to 99.9% killing of an initial inoculum, all 21 strains of enteroc...

A pH indicator and dextrose were incorporated into growth media as a modification of microbial microtiter methods for determining the minimal inhibitory concentration of antimicrobial drugs. This modified method was tested to evaluate the ease of reading end points by changes in the indicator color. Application of the procedure to two media, three indicators, and eight species of bacteria indic...

The minimal inhibitory concentration of lincomycin and clindamycin for a large number of strains from multiple serogroups of streptococci was determined. The median minimal inhibitory concentration for streptococci from groups A, B, C, F, G, H, L, and M and nongroupable organisms ranged from 0.02 to 0.39 mug of lincomycin per ml and from </=0.01 to 0.09 mug of clindamycin per ml. Among the grou...

Six isolates of Legionnaires disease bacteria were tested for their susceptibility to 22 antimicrobial agents. The most active agent was rifampin (minimal inhibitory concentration, </=0.01 mug/ml). On the basis of minimal inhibitory concentration breakpoints that have been used to categorize susceptibility for most of these drugs, the organisms were susceptible to rifampin, cefoxitin, erythromy...

A total of 42 strains of Haemophilus influenzae type b isolated from pediatric patients were sensitive in vitro to temocillin (90% minimal inhibitory concentration = 0.25 microgram/ml). No difference in mean minimal inhibitory concentration between beta-lactamase producer (0.25 microgram/ml) and nonproducer (0.23 microgram/ml) strains was found. Various dosages of ampicillin or temocillin for t...

MK-0366, a new derivative of nalidixic acid, was tested against 250 urinary pathogens including Escherichia coli, Serratia marcescens, and Pseudomonas aeruginosa. This new agent was more active than any of the other antibiotics tested, which included carbenicillin, ampicillin, cephalexin, tetracycline, trimethoprim, trimethoprim-sulfamethoxazole, and nalidixic acid. Gentamicin-resistant P. aeru...

The physicochemical properties, composition and antimicrobial activity of cinnamon essential oil (Cinnamomum zeylanicum) were studied. The bioactivity of this essential oil against Paenibacillus larvae was analyzed by means of a combination of in vitro techniques, such as the tube dilution method and bioautography, a method employed to localize antibacterial activity on a chromatogram. Cinnamal...