Purine metabolic cycle in normal and leukemic leukocytes.

Purine metabolism and reutilization pathways were studied as they applied to normal and leukemic leukocytes. The enzyme activities were expressed in terms of the quantity of protein extracted and per 10(10) cells. Whereas the protein extracted and the enzyme activities from normal lymphocytes were relatively constant, considerable variation was noted in cases of chronic lymphocytic leukemia (CLL).

Silent cholinesterase gene: variations in the properties of serum enzyme in apparent homozygotes.

The cholinesterase activity of the sera of 25 subjects diagnosed as homozygotes for the silent cholinesterase gene was studied by a sensitive enzymatic method employing several thiocholine esters and various inhibitors, and by disc electrophoretic, immunochemical, and chromatographic methods.(a) With one exception, the sera fell into two classes by all criteria. One class (type I, 16 cases) had no normal serum cholinesterase.