Nuclear Medicine Technology and Other Health Applications Project Title: Metabolism of Carbon Labeled Compounds RK-01-03-(e) 16. Technical Progress in FY 1973: (Cont'd) Although a few more patients were included this year in the collaborative studies of oxidation of galactose-U-C-14 to breath 14095 in hypothyroid patients and in patients with liver disease (initiated the previous year) at the Radiation Medicine Centre in Bombay, no definite results are available. The biosynthesis of galactose-U-C-13 (intended for the same application) was pursued at Los Alamos Scientific Laboratory but encountered technical difficulties, so the compound is not yet available. However, tentative arrangements were made for its use both at the University of New Mexico and at Brookhaven National Laboratory. Chemical synthesis of lactose-l-C-13 was initiated at Los Alamos Laboratory. This compound will be used in an oxidation test for lactose intolerance in patients at University of New Mexico hospitals. (Shreeve) A metabolic study of the L-isomers of carbon-14 labeled tryptophan, kynurenine, and hydroxykynurenine in patients with scleroderma was conducted at the F.W. Verwoord Hospital in Pretoria, South Africa. The purpose of the study was to determine whether the South African type of scleroderma had metabolic abnormalities similar to those of the American type. South African scleroderma patients were male caucasian miners whose The illness began with silicosis followed -by later development of scleroderma. Breath carbon dioxide samples were collected in sodium hydroxide over a 24-hour period after the C-14 labeled doses were given and 24-hour urine samples were collected for a three day period. The breath l4co, level for those given tryptophan-7a-C-14 was 6.3 - 8.9 percent; L-hydroxykynurenine~keto-C-14 was 30.6 - 37 percent and L-kynurenine-keto-C-14 was 48.6 - 63,3 percent. The values are similar to those found in the American scleroderma patients given the same compounds. Kynurenine, hydroxykynurenine, xanthurenic acid, kynurenic acid, picolinic acid, quinolinic acid, N-methylnicotinamide, N-methyl-2-pyridone-5-carboxamide and nicotinic acid will be isolated from the urine by carrier techniques and the carbon 14 content of these urinary components determined. The results from these analyses should help determine the particular metabolic abnormalities in males with this disease. This long range project has made little progress due to insufficient technical assistance. The South African Atomic Energy Board (SAAEB) is sending Dr. E.J.P. de Bruin to Brookhaven to spend a year of post-doctorate study at their expense and to belp with the @@laborative projects. Dr. de Bruin will work on the scleroderma, pel™#ra, and hepatic tumor problems. _ he tryptophan metabolic studies in prisoners with a sensitivity to primaquin drugs in the treatment of malaria, were expanded to include a study of kynurenine metabolism. [In collaboration with Dr. Carson at Stateville Prison, Illinois, urine samples were collected from five prisoners before and after loading with tryptophan. The urines were analyzed for 16 tryptophan metabolites to provide control values for other (See Continuation Sheet) L149242 RX- 84 .