The activity of NADH-cytochrome b5 reductase (NADH-methemoglobin reductase) is generally reduced in red cells of patients with recessive hereditary methemoglobinemia. To determine whether this lower activity is due to reduced concentration of an enzyme with normal catalytic properties or to reduced activity of an enzyme present at normal concentration, we measured erythrocyte reductase concentr...

Phenotypic expression of 5-phosphoribosyl 1-pyrophosphate (PRPP) synthetase superactivity was examined in lymphoblast lines derived from six unrelated male patients. Fibroblasts from these individuals have increased rates of PRPP and purine nucleotide synthesis and express four classes of kinetic derangement underlying enzyme superactivity: increased maximal reaction velocity (catalytic defect)...

1. Plasma aspartate transaminase and alkaline phosphatase activities were measured weekly for approximately 30 weeks in a group of healthy males and females. 2. The magnitude of variation of the enzyme activities within any individual was studied with respect to four criteria: (a) the individual’s normal range, (b) the normal range calculated for each sex separately, (c) the clinically accepted...

Leucocyte alkaline phosphatase activity was determined in both cell homogenates and cell extracts. Leucocytes were obtained from normal controls, pregnant females, and patients with various haematological disorders. Enzyme activity presented in terms of phosphorus per minute per 10 neutrophils was more in agreement with the reported cytochemical data in both normal and pathological cases, than ...

Abstract: Congenital enteropeptidase deficiency (CEP), also known as enterokinase deficiency. CEP is an uncommon autosomal recessive genetic disorder mostly characterized by severe chronic diarrhoea after delivery, hypoproteinemia, and failure to grow. Enteropeptidase activity anticipated play a significant role in protein digestion. For growth appropriate development newborns with congenital l...

In most instances, marked deficiency of the purine catabolic enzyme adenosine deaminase results in lymphopenia and severe combined immunodeficiency disease. Over a 2-yr period, we studied a white male child with markedly deficient erythrocyte and lymphocyte adenosine deaminase activity and normal immune function. We have documented that (a) adenosine deaminase activity and immunoreactive protei...

To determine whether decreased alkaline phosphatase activity in the granules from neutrophils of patients with chronic myelogenous leukemia (CML) was due to an absence of enzyme or the production of defective enzyme, we compared the immunologic properties of granule alkaline phosphatase derived from patients with CML with that of normal subjects and patients with polycythemia vera (PRy). Antise...

To determine whether decreased alkaline phosphatase activity in the granules from neutrophils of patients with chronic myelogenous leukemia (CML) was due to an absence of enzyme or the production of defective enzyme, we compared the immunologic properties of granule alkaline phosphatase derived from patients with CML with that of normal subjects and patients with polycythemia vera (PRy). Antise...

To determine whether decreased alkaline phosphatase activity in the granules from neutrophils of patients with chronic myelogenous leukemia (CML) was due to an absence of enzyme or the production of defective enzyme, we compared the immunologic properties of granule alkaline phosphatase derived from patients with CML with that of normal subjects and patients with polycythemia vera (PRV). Antise...