A heat-labile sonic extract of a nonleukotoxic strain of Actinobacillus actinomycetemcomitans caused a dose-dependent inhibition of proliferation of human keratinocytes. Exposure of cells to heat-labile sonic extract for periods as brief as 10 min produced significant suppression of [3H]thymidine uptake 72 h later. I propose that alteration of epithelial barriers may be one pathogenic mechanism...

An extensive blood culture protocol, including prolonged incubation of cultures, for 215 patients believed to have had endocarditis yielded only 3 clinically relevant results. Twenty-four Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, and Kingella (i.e., HACEK) organisms were recovered from standard 5-day blood cultures during the same time period. Specialized methods and not extended...

Florfenicol in vitro activities for a total of 756 bacterial isolates from respiratory tract infections of cattle and swine were comparatively investigated by the agar diffusion method and the microdilution broth method. Florfenicol showed high in vitro activity against Pasteurella multocida, Mannheimia haemolytica, Actinobacillus pleuropneumoniae, and Streptococcus suis, with all of the isolat...

The minimal inhibitory concentrations of 45 antimicrobial agents were determined for 14 strains of Bacterium actinomycetem comitans (Actinobacillus actinomycetem-comitans). All the strains showed good susceptibility to tetracyclines and chloramphenicol, but not to lincomycins. Some strains were clearly resistant to penicillins, cephalosporins, and nitroimidazoles. The lowest minimum inhibitory ...

Reported is a case of Actinobacillus actinomycetemcomitans endocarditis which developed after dental prophylaxis with vancomycin and erythromycin. In vitro results indicated that this isolate and 20 additional isolates were resistant to vancomycin and that potentially useful bactericidal antibiotics for the prophylaxis and treatment of A. actinomycetemcomitans infections included gentamicin, su...

A 5' nuclease TaqMan PCR was developed for the quantitative detection of the periodontopathic bacteria Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis. The relative numbers of bacteria were measured by the comparative threshold cycle method. This simplified method is a way of obtaining the relative quantities of these organisms from specimens and of monitoring the effect of th...

Three cases of pyogenic vertebral osteomyelitis occurred in which unusual, fastidious, Gram negative coccobacilli belonging to the "HB" group were isolated. The organisms were Haemophilus aphrophilus in case 1, intermediate between H aphrophilus and Actinobacillus actinomycetemcomitans in case 2, and Eikenella corrodens in case 3. All HB bacteria are sensitive to a wide range of antibiotics.