Showing papers on "Bacillus anthracis published in 1971"

Antibiotic Susceptibility of Bacillus Species

Abstract: Organisms of the genus Bacillus are aerobic, sporeforming, usually gram-positive rods which, with the exception of Bacillus anthracis, have been implicated infrequently in human disease. These organisms are ubiquitous and commonly occur as contaminants in cultures of clinical material. However, well-documented cases of disseminated infection with these organisms in man have been described [1-3]. Recently, we observed a fatal case of pneumonia and bacteremia due to Bacillus cereus in a patient with subacute lymphocytic leukemia. Lack of information on the susceptibility of Bacillus species to antimicrobial agents was a handicap in treating this patient. Patients with markedly impaired host resistance are now frequently encountered, and information on the antimicrobial susceptibility of "non-pathogenic" bacteria that may infect these patients is desirable. For this reason, the in-vitro susceptibilities to selected antibiotics of 49 strains representing six species of Bacillus were studied.

Anthrax Indirect Microhemagglutination Test

Abstract: A new application of the indirect microhemagglutination (IMH) test has been developed for anthrax. The antigen was prepared by DEAE cellulose, Dowex 1-X1, and Sephadex G-50 column chromatography of a culture filtrate of the avirulent, non-proteolytic, non-encapsulated Vollum strain of Bacillus anthracis grown anaerobically in a chemically defined liquid medium. Tanned, sensitized sheep red blood cells (SRBC) were tested with complement-inactivated SRBC-absorbed serum samples from 72 anthrax patients, 91 persons who had been vaccinated against anthrax, and 103 controls. The IMH test detected antibodies in 93% of patients, 98% of vaccinees, and none of the controls. Run-to-run reproducibility was 76% within one twofold dilution, and 93% within two twofold dilutions. The IMH test proved more sensitive and less time-consuming than the currently used agar-gel precipitation inhibition (AGPI) test.

Agar diffusion method for the differentiation of Bacillus anthracis.

Abstract: A method was developed for identification of Bacillus anthracis based on elaboration of protective antigen by individual colonies and its detection by double-diffusion precipitation in agar plates.

Effect of the method of agitation on the accumulation of protective antigen in cultures of Bacillus anthracis.

Abstract: Accumulation of protective antigen was essentially independent of culture volume, provided the organisms were kept in suspension by stirring. Agitation by orbited shaking was unsatisfactory.