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W H Traub

Publications and source records attributed to W H Traub.

At least 145 records · Page 8Linked to original sources
PubMed1972

Evaluation of the in vitro activity of tobramycin as compared with that of gentamicin sulfate.

The in vitro activity of tobramycin was quantitatively compared with that of gentamicin sulfate against 195 bacterial isolates from clinical material. Tobramycin was found to be twice as active as gentamicin against isolates of Pseudomonas aeruginosa. Conversely, gentamicin proved fourfold more active than tobramycin against isolates of Serratia marcescens. Both drugs were of comparable activity against isolates of Staphylococcus aureus and the majority of the enterobacterial isolates other than S. marcescens. On the basis of the obtained data, the following criteria are proposed for the interpretation of diffusion susceptibility tests with 10-mug discs of gentamicin and tobramycin. Enterobacteriaceae and isolates of S. aureus are designated as susceptible to gentamicin and tobramycin if the zones of inhibition measure 15 mm or more in diameter; zones of 14 mm or less are indicative of resistance. Pseudomonadaceae are interpreted as sensitive to tobramycin and gentamicin if the inhibition zones measure at least 15 and 12 mm in diameter, respectively.

Amino Sugars↗
PubMed1972

Bacteriocin typing of Serratia marcescens isolates of known serotype-group.

The number of isolates of Serratia marcescens that could be typed by sensitivity to bacteriocins was compared with the nature of the serotype/-group of each of the isolates. Ninety-four of 101 isolates (93.1%) could be bacteriocin-typed; this compares with 80 of the isolates (79.2%) that had been serotyped, and with 91 of the isolates (90.1%) that carried determinable O antigens. It is recommended that bacteriocin typing of S. marcescens be adopted by reference laboratories, because this technique is simple, inexpensive, and appears to be of somewhat higher epidemiological resolution than classic serological procedures.

Bacteriocins↗
PubMed1972

Continued surveillance of Serratia marcescens infections by bacteriocin typing: investigation of two outbreaks of cross-infection in an intensive care unit.

During an 8.5-month period, 198 additional isolates of Serratia marcescens were typed by bacteriocin sensitivity; 154 isolates were typable and were categorized according to our current system of 54 provisional bacteriocin sensitivity patterns. Two outbreaks of nosocomial infection due to S. marcescens occurred in our intensive care unit, involving two and five patients, respectively. The latter outbreak was caused by a strain of S. marcescens which was not sensitive to any of the 10 bacteriocins normally used. Therefore we developed a supplementary procedure based on bacteriocin production rather than bacteriocin sensitivity. Bacteriocin production was induced with mitomycin C, and the crude lysates were applied to 15 provisional bacteriocin indicator strains. The reverse typing procedure was necessary to determine the spread and ultimate subsidence of this particular outbreak of cross-infection.

Bacteriocins↗
PubMed1971

Medium-dependent activity of gentamicin sulfate against enterococci.

Routine disc diffusion susceptibility tests (Bauer-Kirby technique), employing 5% sheep blood-Mueller-Hinton agar and 10-mug gentamicin sulfate discs, disclosed that a significant number of clinical enterococcal isolates were sensitive to the antibiotic, as also revealed by the agar dilution technique. With few exceptions, the isolates proved resistant to this antibiotic when tested for susceptibility in Brain Heart Infusion and Trypticase soy broth or agar. The addition of 5% sheep blood to Trypticase soy and Brain Heart Infusion agars resulted in markedly enhanced activity of the antibiotic, indicating medium-dependent activity of gentamicin against enterococci. Human serum and urine failed to support optimal growth of enterococci. Thus, it was not possible to correlate the activity of gentamicin in any of the media examined with that in serum or urine.

Agar↗
PubMed1971

Bacteriocin (Marcescin) typing of clinical isolates of Serratia marcescens.

A simple, reproducible technique is described for bacteriocin typing of clinical isolates of Serratia marcescens. With 10 marcescin-producer strains, a total of 46 of 50 isolates (92%) of S. marcescens could be typed and categorized into 16 provisional types according to their sensitivity or tolerance to marcescins. The potential significance of this procedure with regard to delineation of outbreaks of nosocomial infection is discussed on the basis of preliminary epidemiological data.

Bacteriocins↗