Samuel Saslaw

Enhancement of Growth of certain Fungi by Streptomycin.

Summary Streptomycin incorporated into a synthetic liquid medium enhanced the growth of laboratory strains of S. schenckii, C. immitis, P. verrucosa, T. mentagrophytes, and H. capsulatum which had not been previously exposed to this antibiotic.

A Method for Demonstrating Antibodies in Rabbit Sera Against Histoplasmin by the Collodion Agglutination Technic

Summary A method for utilizing suspensions of collodion particles sensitized with histoplasmin for the determination of antibodies against histoplasmin is described. The sensitized suspensions uniformly showed the presence of antibodies against histoplasmin in rabbits which had been immunized with 3 different strains of H. capsulatum. Anti-sera against B. dermatitidis reacted in low dilution, while that of B. braziliensis, S. schenckii, C. neoformans and C. albicans as well as normal rabbit sera failed to agglutinate the histoplasmin-coated particles. These results suggest the use of this technic with human sera. The findings of such studies are now being analyzed in this laboratory.

Use of mucin in experimental infections of mice with Histoplasma capsulatum.

Summary and Conclusions H. capsulatum in the yeast phase when suspended in 5% hog gastric mucin and administered intraperitoneally into white mice caused a high percentage of fatal indections. Equivalent challenge doses of the organism suspended in saline rarely caused dleath. It was observed that by varying the number of organisms administered in mucin the mortality rate as well as the time interval between injection and death could be altered to suit the experimental requirements. Certain investigations on experimental histoplasmosis heretofore have been limited by the relative resistance of white mice to infection with H. capsulatum. “Virulence-enhancement” by mucin offers a means of extending the scope of such studies.

Tobramycin: in vitro and clinical evaluation in 30 patients.

Clinical evaluation of intramuscular tobramycin was accomplished in 30 patients with respiratory, soft tissue, urinary tract, bone or septicemic infections due to gram negative bacilli. Median sensitivity to tobramycin of Pseudomonas aeruginosa isolates (19 strains) was 0.62 µg/ml and range 0.31–2.5 µg/ml; less activity was observed for Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae and Enterobacter species isolates but median minimum inhibitory concentrations were ≤ 2.5 µg/ml. Therapy resulted in clinical and bacteriologic cures in 16 patients (53 per cent) including 13 of 16 (81 per cent) with urinary tract infections; 9 of the 14 patients who did not obtain bacteriologic cure had satisfactory clinical responses. Tobramycin was effective for selected gram negative bacillary infections and particularly for P. aeruginosa.