A rapid, miniaturized, urea broth test useful for detecting urease activity of yeasts was compare... more A rapid, miniaturized, urea broth test useful for detecting urease activity of yeasts was compared to Christensen urea agar. All urease-producing yeasts tested were positive on both media; however, 60% were reactive in the urea R broth within 30 min, and the remainder were reactive within 4 h. This urea multiwell test may be useful as a rapid screening method for detecting urease-producing yeasts recovered from clinical specimens and as an adjunct test with other rapid methods of yeast identification.
A total of 463 respiratory specimens, all smear positive for acid-fast bacteria, were inoculated ... more A total of 463 respiratory specimens, all smear positive for acid-fast bacteria, were inoculated onto routine solid media and into BACTEC 7H12 Middlebrook medium for detection of mycobacterial growth. Conventional drug susceptibility testing (1% proportion method) was performed ...
An enzymatic method involving a protease (pronase) for the elimination of interference factors in... more An enzymatic method involving a protease (pronase) for the elimination of interference factors in the latex test for cryptococcal antigen was developed and compared with dithiothreitol treatment. The two were equivalent in their ability to remove interference factors; however, the enzymatic method generally yielded higher titers. The method is simple, requires only 20 min, and makes the latex test for cryptococcal antigen specific.
An evaluation was undertaken to determine the optimal method for the in vitro susceptibility test... more An evaluation was undertaken to determine the optimal method for the in vitro susceptibility testing of 26 Nocardia asteroides complex isolates to the following antimicrobial agents: amikacin, ampicillin, amoxicillin-clavulanate, ceftriaxone, ciprofloxacin, erythromycin, imipenem, minocycline, and trimethoprim-sulfamethoxazole. Five testing methods were studied including the agar dilution, broth microdilution, and disk diffusion methods, the epsilometer test (E-test), and the BACTEC radiometric method. Results for each antimicrobial agent and each testing method were interpreted as indicating susceptibility, intermediate susceptibility, or resistance according to current guidelines of the National Committee for Clinical Laboratory Standards (NCCLS) for bacteria that grow aerobically and were then compared to a "gold standard" susceptibility test result. The gold standard result for each Nocardia isolate was established by a consensus of the results of the majority of testi...
A system has been developed for the identification of aerobic actinomycetes in the clinical labor... more A system has been developed for the identification of aerobic actinomycetes in the clinical laboratory based on analysis of whole cells for diaminopimelic acid and carbohydrates and on the ability of the organism to decompose casein, tyrosine, and xanthine media. The whole-cell analyses were performed by a simple thin-layer chromatographic procedure that is described. Eighteen reference cultures were correctly identified and, subsequently, 35 isolates from clinical material were grouped by using this system. The method is well suited for use in routine clinical laboratories.
A rapid, miniaturized, urea broth test useful for detecting urease activity of yeasts was compare... more A rapid, miniaturized, urea broth test useful for detecting urease activity of yeasts was compared to Christensen urea agar. All urease-producing yeasts tested were positive on both media; however, 60% were reactive in the urea R broth within 30 min, and the remainder were reactive within 4 h. This urea multiwell test may be useful as a rapid screening method for detecting urease-producing yeasts recovered from clinical specimens and as an adjunct test with other rapid methods of yeast identification.
A total of 463 respiratory specimens, all smear positive for acid-fast bacteria, were inoculated ... more A total of 463 respiratory specimens, all smear positive for acid-fast bacteria, were inoculated onto routine solid media and into BACTEC 7H12 Middlebrook medium for detection of mycobacterial growth. Conventional drug susceptibility testing (1% proportion method) was performed ...
An enzymatic method involving a protease (pronase) for the elimination of interference factors in... more An enzymatic method involving a protease (pronase) for the elimination of interference factors in the latex test for cryptococcal antigen was developed and compared with dithiothreitol treatment. The two were equivalent in their ability to remove interference factors; however, the enzymatic method generally yielded higher titers. The method is simple, requires only 20 min, and makes the latex test for cryptococcal antigen specific.
An evaluation was undertaken to determine the optimal method for the in vitro susceptibility test... more An evaluation was undertaken to determine the optimal method for the in vitro susceptibility testing of 26 Nocardia asteroides complex isolates to the following antimicrobial agents: amikacin, ampicillin, amoxicillin-clavulanate, ceftriaxone, ciprofloxacin, erythromycin, imipenem, minocycline, and trimethoprim-sulfamethoxazole. Five testing methods were studied including the agar dilution, broth microdilution, and disk diffusion methods, the epsilometer test (E-test), and the BACTEC radiometric method. Results for each antimicrobial agent and each testing method were interpreted as indicating susceptibility, intermediate susceptibility, or resistance according to current guidelines of the National Committee for Clinical Laboratory Standards (NCCLS) for bacteria that grow aerobically and were then compared to a "gold standard" susceptibility test result. The gold standard result for each Nocardia isolate was established by a consensus of the results of the majority of testi...
A system has been developed for the identification of aerobic actinomycetes in the clinical labor... more A system has been developed for the identification of aerobic actinomycetes in the clinical laboratory based on analysis of whole cells for diaminopimelic acid and carbohydrates and on the ability of the organism to decompose casein, tyrosine, and xanthine media. The whole-cell analyses were performed by a simple thin-layer chromatographic procedure that is described. Eighteen reference cultures were correctly identified and, subsequently, 35 isolates from clinical material were grouped by using this system. The method is well suited for use in routine clinical laboratories.
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