Wallace E. Herrell

SOME BACTERIOLOGIC, PHARMACOLOGIC, AND CLINICAL OBSERVATIONS ON TERRAMYCIN

Terramycin* is an interesting antibiotic agent described first by Finlay and colleagues. That this substance possessed considerable antimicrobial activity was evident from their report. Our preliminary studies on the substance have already been reported? We have continued our investigations of this antibiotic agent, and the present report concerns itself with some r e cent observations concerning acquired resistance to this substance, a summary of our available information concerning its absorption, ditrusion, and excretion and, in addition, a summary of our clinical experience in the treatment of 30 patients with this agent.

Bilateral granulosa cell tumors

Abstract Bilateral tumors of the ovaries were discovered when the child was fourteen weeks of age, and the tumors were successfully removed when she was sixteen weeks of age. Two years and eight months later these tumors were determined to be granulosa cell tumors. The patient seems to be the youngest yet to be reported to have had this disease. When this report was written, three years and two months subsequent to operation, the girl was apparently well. The case is one of that small group (5 to 10 per cent) of cases in which the condition occurs before puberty. It is further unique in that the tumors were bilateral; bilaterality occurs in not more than 5 per cent of all cases of granulosa cell tumor.

Mode of Action of Gramicidin

Conclusions 1. Gramicidin and tyrocidine depress the surface tension of aqueous solutions. Tyrocidine is more active in this regard than is gramicidin. 2. The ability of gramicidin to depress surface tension is improved by the addition of organic solvents such as glycerin which increases the solubility of gramicidin. 3. Serum decreases the activity of tyrocidine less than it does the activity of gramicidin, sodium oleate and aerosol OT. 4. The bactericidal and hemolytic effects of gramicidin are destroyed by heat but its property of altering surface tension is heat stable.

Hemolytic Effect of Gramicidin

Summary Gramicidin has a powerful hemolytic action against rabbits and sheeps erythrocytes in vitro. This activity is marked even in the presence of serum, plasma and tissue extract. The presence or absence of complement did not appear to affect the process.

Treatment of Brucellosis with Aureomycin or Terramycin Combined with Dihydrostreptomycin

Two combinations of antibiotics have been used in treating culturally proved brucellosis: (1) the simultaneous administration of aureomycin® and dihydrostreptomycin; (2) the simultaneous use of terramycin and dihydro-streptomycin. Both combinations are equally effective. The recovery rate with either method has been 95 per cent. The combined use of terramycin or aureomycin and dihydro-streptomycin has not been presented as a specific treatment of brucellosis, but results to date justify the conclusion that either combination is far superior to any other currently available therapy. Furthermore, the undesirable toxic reactions sometimes experienced with other methods have not occurred.

Effect of Serum on Hemolysis by Gramicidin and Tyrocidine

Summary When gramicidin or tyrocidine in minimal effective amounts is added to suspensions of washed sheep erythrocytes, the rate of hemolysis is much more rapid with tyrocidine than with gramicidin but the latter, a!though slower in action, ultimately causes a greater degree of hemolysis than the former. Comparative experiments have been done to determine the influence of horse serum on the rate and amount of hemolysis caused by gramicidin and tyrocidine. The hemolytic activity of both substances is decreased in the presence of only 1% of horse serum. Five percent of serum causes further inhibition of the hemolytic activity of gramicidin and completely prevents hemolysis by tyrocidine. Increasing the amount of serum beyond 5% did not result in a further decrease of the hemolytic activity of gramicidin.