Human salivary arginase and its deficiency in argininaemia.

Arginase from normal human mixed saliva was characterized. The enzyme was completely activated after a preincubation of 20 min at 55 degrees C and a Mn2+ final concentration of 5 mmol/l. The pH optimum was 9.

[CNS tumors with the clinical picture of meningitis].

Incidentally CNS tumours may simulate acute bacterial or viral meningitis, cerebral abscess, and tuberculous or luetic basal meningitis. 64 cases from the literature are analysed together with 2 personal observations. This form of presentation is found most frequently in high-grade malignancy, i.

[Congenital hypophosphatasia].

Hypophosphatasia represents an inborn enzymatic deficiency characterized by a reduced activity of alkaline phosphatase in serum and tissue and an increased urinary excretion of phosphoethanolamine. 278 cases have been described until the end of 1980. Based on the age of manifestation and the predominant clinical findings the following classification is possible: The prenatal form (49 cases) with caput membranaceum, skeletal deformities and respiratory distress has a mortality of 100%.

Hyperargininemia: the rat as a model for the human disease and the comparative response to enzyme replacement therapy with free arginase and arginase-loaded erythrocytes in vivo.

Rat erythrocytes lack arginase as do the erythrocytes of human homozygote patients with hyperargininemia due to arginase deficiency. The rat has physiological liver arginase activity and plasma arginine and ornithine levels between the homozygotes and the heterozygotes with hyperargininemia. In rats, one injection of free arginase induces a transient exogenous arginase effect which is abolished after 24 hr.

Measurement of arginine transport in human erythrocytes using their intrinsic arginase activity: implications for the treatment of familial hyperargininemia.

A procedure making use of the intracellular arginase activity has been developed for measuring the transport of arginine across the human erythrocyte membrane. (1) The arginine translocation is carrier mediated with simple Michaelis-Menten kinetics, showing one high affinity, low capacity transport system characterized by a half saturation constant KT of 0.177 +/- 0.