Complete deficiency of adenine phosphoribosyltransferase. Report of a family

We studied the clinical and biochemical manifestations of complete adenine phosphoribosyltransferase deficiency in the kindred of a male homozygous child excreting stones of 2,8-dihydroxyade-nine. Abnormal amounts of adenine, 8-hydroxyade-nine and 2,8-dihydroxyadenine (25 per cent of total purine metabolites) appeared in the urine of the propositus and his clinically normal brother, but not in heterozygotes or a control. Adenine phosphoribosyl-transferase activity in erythrocytes was less than 1 per cent of normal in both homozygotes and varied from 20 to 57 per cent of normal in six heterozygotes. Heterozygotes exhibited neither hyperuricemia nor gout. Treatment of the propositus with allopurinol and a low purine diet stopped stone formation. In addition, excretion of 2,8-dihydroxyadenine decreased. An autosomal recessive mode of inheritance with variable expression in the phenotype is indicated. Homozygotes may be detected by their raised urinary adenine levels or absence of detectable erythrocyte adenine phosphoribosyltransferase activity (or both).

Cellular immunity to human basic myelin protein in women with dysplasia and carcinoma in situ of the cervix

Sensitization to human myelin basic protein or encephalitogenic factor (EF), and antigen thought to be analogous to different human tumours, can be measured by the macrophage migration inhibition test (MMI). The MMI test was done on one occasion in 51 women with dysplasia and carcinoma in situ of the cervix; 20 women with non-malignant gynaecological conditions served as controls. Sensitization to EF was found in 71 per cent of women with carcinoma in situ and 42 per cent of women with dysplasia. None of the controls showed sensitization. Sensitization could not be related to histological evidence for cellular infiltration within the cervix.

THE KINETICS OF CONSECUTIVE SECOND ORDER REACTIONS

A study of consecutive competitive second order reactions is reported. It is shown that identical equations can be obtained by two different approaches. A static method is described where equations are developed by considering the changes brought about in the system by the addition of small quantities of one of the reactants. Equations are also developed from the point of view of kinetics. These equations express the concentrations of the products as functions of the concentration of one of the reactants and the ratio of the velocity constants.