CHOLERA, PLAGUE, SMALLPOX, TYPHUS FEVER, AND YELLOW 1 From medical officers of the Public Health Service, American consuls, and other sources. For reports received from Dee. 30, 1922, to June 29, 1923, see Public Health Reports for June 29, 1923. The tables of epidemic diseases are terminated semiannually and new tables begun. CHOLERA, PLAGUE, SMALLPOX, TYPHUS FEVER, AND YELLOW FEVER-Continued. Reports Received from June 30 to July 20, 1923—Continued. CHOLERA, PLAGUE, SMALLPOX, TYPHUS FEVER, AND YELLOW FEVER Continued. Reports Received from June 30 to July 20, 1923-Continued. CHOLERA, PLAGUE, SMALLPOX, TYPHUS FEVER, AND YELLOW FEVER-Continued. Reports Received from June 30 to July 20, 1923—Continued. PUBLIC HEALTH REPORTS VOL 38 AUGUST 3, 1923 STANDARDIZATION OF INSULIN. No. 31 1. TOXICITY OF INSULIN FOR WHITE RATS AS INFLUENCED BY TEMPERATURE OF ROOM IN WHICH ANIMALS ARE KEPT. BY CARL VOEGTLIN, Professor of Pharmacology, and EDITH R. DUNN, Scientific Assistant, Division of Pharmacology, Hygienic Laboratory, United States Public Health Service. One of the most difficult problems presented since the introduction of insulin for the treatment of diabetes has been the development of a satisfactory and relatively simple method for the determination of the therapeutic potency of this drug. It is, of course, very important that the physician should receive a product of uniform activity and free from any toxic impurities, and which will permit him to administer the proper dosage to his patients. As a result of the efforts of the Toronto investigators, a method of bio-assay has been worked out which is based on the determination of the dose of insulin which will reduce the blood sugar of fasting (24 hours) rabbits to a level where convulsions will occur. In practice it has been found that rabbits exhibit a great individual variation in susceptibility to insulin, and this has necessitated, according to information furnished by Doctor Clowes, of the Eli Lilly Co., the use of from 100 to 500 rabbits for the bio-assay of each lot of the drug. It is obvious that this means a very considerable expense in money and time. For this reason we have undertaken some work in order to secure, if possible, a simplification of the method. Experience with the biological standardization of arsphenamine and its substitutes has suggested the use of a standard strain of albino rats in place of rabbits, as previous experience has shown us that the standardization of the animals used in the bio-assay of drugs is of the greatest importance. It is almost impossible to secure a sufficient supply of standard rabbits. The idea occurred. to us that the determination of the minimum lethal dose (M. L. D.) of insulin in rats might serve as a pretty good index of the potency of such preparations. This method has, of course, one chief disadvantage, owing to the possibility of the disturbing interference of toxic impurities. However, the process of manufacture of insulin (1747) 55082-23-1 |