A simple gas chromatographic (GC) method has been developed to determine 2,4- and 2,6-diaminotoluenes in polyurethane foam. Diaminotoluenes were reacted with heptafluorobutyric anhydride in toluene, and the products, bis-heptafluorobutyrates, were determined by GC, using a 3% silicone OV-330 column. The 2,4- and 2,6-diaminotoluenes can be detected as heptafluorobutyryl derivatives by using an electron capture detector at levels of 5 and 2 pg, respectively. Finally, 2.7-3.0 micrograms/g of 2,4- and 1.3-1.9 micrograms/g of 2,6-diaminotoluene were detected in 3 commercial polyurethane foams.

Chromatography, Gas↗

PubMedDate not supplied

HLA antigen and susceptibility to leprosy.

Fifty-nine leprosy patients (31 tuberculoid, 28 lepromatous) have been HLA typed and compared to 125 healthy individuals who have had no known contact with leprosy patients in the past. HLA antigens were determined by the microdroplet lymphocyte toxicity method developed by Prof. Terasaki of UCLA. In order to detect 31 HLA antigens, a total of 58 antisera were used in a No. T-7 research tray. AW24 antigen showed the most remarkable deviation. The frequency of this antigen in leprosy patients was 25.4% and that in normal subjects of the control group was 63.2%. The difference in frequency between the two groups was statistically significant when the p value was corrected for the number of antigens being tested. Uncorrected p values of the BW39, A9, and B8 antigens were also statistically significant. Frequencies of the majority of HLA antigens in tuberculoid leprosy patients were similar to those of corresponding HLA antigens in lepromatous leprosy patients.

HLA Antigens↗