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A Balows

Publications and source records attributed to A Balows.

At least 37 records · Page 2Linked to original sources
PubMed1973

In-use evaluation of a commercially available set of quality control cultures.

Increasing awareness of the need for a uniform quality control program prompted an evaluation of a commercially available set (Bact-Chek) of eight organisms. A protocol was designed in which this set of control cultures was tested simultaneously in the clinical microbiology laboratory of a 400-bed hospital (the Berkshire Medical Center) and in the reference laboratories of the Bacteriology Section of the Center for Disease Control. The results indicate that the Bact-Chek organisms are essentially as advertised: they constitute a basic set of cultures for a quality control program in clinical microbiology. Ninety per cent of the media and reagents (excluding mycobacterial media and reagents) in the clinical laboratory were checked with this set of eight cultures. Additional cultures not in the set were used to check the remaining 10% of the media and reagents.

Bacteria↗
PubMed1973

Auxotab--a device for identifying enteric bacteria.

A multitest system called the Auxotab that uses ten dehydrated reagents on a paper card has been evaluated with 417 known stock cultures of Enterobacteriaceae. In double-blind studies with the Auxotab, 87% of the strains tested were correctly identified. Results of this study indicate that there is a need for modification of the product in regard to ease of handling, time required for use, and accuracy of identification of enteric bacteria.

Bacteriological Techniques↗
PubMed1973

Evaluation of the redesigned enterotube--a system for the identification of Enterobacteriaceae.

The redesigned Enterotube has been evaluated with 414 unknown Enterobacteriaceae cultures from the stock culture collection of the Center for Disease Control. When the Enterotube was used as recommended by the manufacturer, an average of 96.4% of these cultures were correctly identified. Only two groups (Salmonella and Edwardsiella) were identified with less than 90% accuracy (89.2 and 87.5%, respectively). The Enterotube now provides a convenient, rapid, and accurate test system for the identification of typically reacting enteric bacteria.

Bacteriological Techniques↗
PubMed1973

Micromethod system for identification of anaerobic bacteria.

A micromethod multitest system prepared by Analytab Products, Inc. and conventional tests employed at the Center for Disease Control for identification of anaerobes were compared. All procedures were conducted in an anaerobic glove box. A total of 104 cultures, including 18 reference strains and 86 diagnostic cultures, were examined. Ninety-one percent of the total tests performed with the two systems were in agreement. Greater than 90% agreement between the two systems was obtained with 12 of the 17 differential tests compared. The tests for nitrate reduction and H(2)S production gave the poorest agreement, 77.8 and 80.8%, respectively. Only 66% of the 86 diagnostic cultures could be presumptively identified with the micromethod system supplemented only with microscopy and colonial characteristics. However, when appropriate supplementary tests and gas-liquid chromatography were used with the micromethod system, 85% of the 86 strains could be identified. When Ehrlich reagent, instead of Kovac reagent, was used with the micromethod to test for indole, the agreement in identification was raised to 93%.

Anaerobiosis↗
PubMed1971

Antibiotic susceptibility patterns of recent isolates of Corynebacterium diphtheriae.

A variety of factors which might affect zone sizes were studied with strains of Corynebacterium diphtheriae; a standard disc method for antimicrobial sensitivity testing was used. Moderate variations in inoculum size, inoculum preparation, and pH of Mueller Hinton agar (MHA) did not appreciably affect zone sizes. The addition of blood to MHA was necessary to insure the growth of all C. diphtheriae strains on all lots of MHA. Zone diameters on MHA with blood were consistently 4 to 9 mm smaller than on plain MHA; however, zone diameters were within the sensitive range for seven antibiotic discs used on both media. Minimal inhibitory concentration (MIC) values for penicillin, erythromycin, and rifampin were determined by a plate dilution method. The geographical source, toxigenicity, and type of the strains showed no significant correlation with MIC values or zone diameters for eight antibiotic discs. When MIC values were compared to obtainable blood levels, all of the strains appeared to be sensitive with MIC values of </= 0.5 mug/ml for penicillin and </= 0.01 mug/ml for erythromycin and rifampin. Strains from persons who failed to have C. diphtheriae eliminated by one course of treatment with penicillin or erythromycin were examined. The susceptibility of these strains did not vary significantly from that of the other strains studied.

Animals↗
PubMed1971

R-B enteric differential system for identification of Enterobacteriaceae.

The R/B Enteric Differential System for identifying enteric bacteria has been evaluated with 451 "unknown" cultures from the stock culture collection of the Center for Disease Control. An average of 89.6% of these cultures were correctly identified by the R/B system, when used as recommended by the manufacturer but without the assistance of serology. This percentage ranged, however, from 47% for Klebsiella to 100% for Serratia and Providencia. Of 11 groups or genera of Enterobacteriaceae tested, only three (Enterobacter, Serratia, and Providencia) were identified with 95% or better accuracy. Four groups (Arizona, Citrobacter, Escherichia, and Salmonella) attained 90 to 95% accuracy of identification, and three groups (Edwardsiella, Proteus, and Shigella) scored between 85 and 90% accuracy. We recommend the R/B system as a screening device which is reasonably successful in grouping bacteria but not as a substitute for more exacting conventional procedures.

Bacteriological Techniques↗
PubMed1970

Susceptibility of Neisseria meningitidis strains from the civilian population to sulfadiazine, penicillin, and rifampin.

The minimal inhibitory concentration (MIC) values of sulfadiazine, penicillin, and rifampin for meningococcal strains isolated from civilians during 1970 were compared. The strains were isolated from various sources and geographical areas and represented several serogroups. The ranges of MIC values were as follows: 0.05 to 20 mg/100 ml for sulfadiazine, 0.01 to 0.4 mug/ml for penicillin, and 0.01 to 0.8 mug/ml for rifampin. There was no significant relationship between MIC values of sensitive or resistant sulfadiazine strains and the MIC values to the other two antimicrobial agents. Comparisons of sulfadiazine MIC values with inhibition zones around sulfathiazole discs showed excellent correlation, provided the strains were separated into sensitive and resistant groups on the basis of growth at 1 mg/100 ml. Regression curves for penicillin and rifampin sensitivity showed homologous sensitive populations with the strains studied.

Female↗