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PubMed1990

Effect of cisplatin and other biological response modifiers on the activity of lysozyme, plasminogen activator and 5' nucleotidase by murine macrophages in vitro.

In vitro effect of cisplatin and other biological response modifiers has been studied. It is observed that in vitro treatment of macrophage monolayers with cisplatin, rIFN Y, LPS or MDP either alone or in combination showed significantly increased activity of lysozyme, plasminogen activator and decreased activity of 5' nucleotidase. Priming of macrophages with rIFN Y had a significant effect in enhancing the activity of lysozyme and plasminogen activator when subsequently treated with cisplatin, MDP or LPS.

5'-Nucleotidase↗
PubMedDate not supplied

The clinical biochemistry of 5'-nucleotidase.

This review delineates the subcellular distribution, biochemical characteristics, and metabolic functions of 5'-nucleotidase (5'NT), summarizes the analytical biochemistry of 5'NT, and assesses the clinical significance of 5'NT determinations in body fluids, cells, and tissues. Salient aspects of the clinical biochemistry of 5'NT, discussed herein, are as follows: (A) Serum 5'NT activity is generally elevated in hepatobiliary diseases, especially with intrahepatic obstruction, but, unlike serum alkaline phosphatase, serum 5'NT activity is not increased in infancy, childhood, pregnancy, or osteoblastic disorders. (B) In cancer patients, elevated serum 5'NT activity does not always indicate hepatobiliary involvement; in some cases, 5'NT may be released into serum from the primary tumor or local metastases. (C) Genetic deficiency of erythrocyte pyrimidine 5'NT activity is a common cause of hereditary non-spherocytic hemolytic anemia. (D) Acquired deficiency of erythrocyte pyrimidine 5'NT activity occurs in patients with beta-thalassemia and lead poisoning. (E) 5'NT activity is low in circulating monocytes, increases markedly upon their differentiation to tissue macrophages, and subsequently diminishes during macrophage activation. (F) Lymphocyte ecto-5'NT activity, a plasma membrane marker of cell maturation, is generally low in immunodeficiency states, and undergoes characteristic changes in patients with certain lymphomas and leukemias.

5'-Nucleotidase↗
PubMedDate not supplied

Pyrimidine 5'-nucleotidase and oxidative damage in red blood cells transfused to beta-thalassemic children.

Pyrimidine 5' nucleotidase (P5'N) acquired deficiency has been found in several hematologic disorders including beta-thalassemia. Our previous studies suggested that the aldehydes produced during membrane lipid peroxidation could play a role in P5'N inactivation in thalassemia. To evaluate the effects of the thalassemic "environment" on transfused red blood cells, we tested P5'N, pyruvate kinase (PK), glucose 6-phosphate dehydrogenase (G-6PD) activity, creatine content, reduced glutathione (GSH) levels and the hexose monophosphate shunt (HMS) in the red cells of homozygous transfusion-dependent thalassemic children, immediately following and again one month after transfusion. In red cells aged in thalassemic plasma, P5'N activity, creatine level, GSH stability and stimulated HMS flux were significantly decreased. These results fit in with the presence in thalassemic plasma of molecules interfering with antioxidant red cell defenses. Normal red cells incubated in thalassemic plasma display a significant stimulation of the basal HMS (p less than 0.01). Transfused red cell metabolic alterations could be explained by the plasma pro-oxidant activity and may contribute to reducing red cell survival in the host plasma.

5'-Nucleotidase↗
PubMedDate not supplied

[The effect of hydrocortisone on the activity of 5'-nucleotidase and adenosine deaminase in the hypothalamus and hippocampus of the rat brain].

The effect of single (1.4 and 24 h) and long-term (7 days) hydrocortisone intramuscular administration (5 mg/100 g of body mass) on 5'-nucleotidase and adenosine deaminase activities in homogenate and subcellular fractions of the rat brain hypothalamus and hippocampus has been studied. Enzymatic activity of adenosine metabolism in hypothalamus and hippocampus has been shown to undergo changes with the duration of hydrocortisone administration. A possible role of adenosine in the mechanism of glucocorticoid action in the CNS and the regulation of the hypothalamic-pituitary-adrenal axis is under discussion.

5'-Nucleotidase↗
PubMed1989

Increased density of ecto 5' nucleotidase antigen on leukemic T cells from patients with cutaneous T-cell lymphoma and adult T-cell leukemia/lymphoma.

Malignant CD4+ T cells in adult T-cell leukemia/lymphoma (ATL) and cutaneous T-cell lymphoma (CTCL) express a number of cell surface molecules that are upregulated on normal T cells activated by foreign antigen. In this report we describe an interesting exception to the parallel phenotypic features of activated T cells and malignant CD4+ T cells. A monoclonal antibody (MoAb; termed 27.2) that was raised to HTLV-1+, CD4+25+ leukemic T cells stained weakly 25% of peripheral T cells, including approximately 50% of CD8+ T cells and 20% of CD4+ T cells. Flow cytometry analysis indicated that the surface density of the 27.2 antigen was unchanged or diminished when normal T cells were activated by antigen. However, 3/4 Sezary cases and 4/8 cases of ATL had relatively high densities of the 27.2 antigen. Immunoprecipitation and sodium dodecylsulfate polyacrylamide gel electrophoresis of the NP-40-solubilized membranes of surface-iodinated ATL cells indicated that MoAb 27.2 reacted with a 75 Kd molecule. The size and distribution of the 27.2 antigen on T cell subsets suggested that it might be the enzyme ecto-5' nucleotidase (NT), a phosphatidylinositol-linked enzyme that catalyzes dephosphorylation of monophosphate nucleotides to their respective nucleosides. This was confirmed by demonstrating that lymphocyte ecto-5'NT activity was blocked partially and inhibited completely by preincubating cells with MoAb 27.2 for 1 hour at 4 degrees C and 24 hours at 37 degrees C, respectively. When used with a second MoAb (27.1) to a novel T cell activation antigen found on all CTCL and ATL leukemias examined, 27.2 was found to discriminate between normal and leukemic T cells in two patients with ATL. These studies suggest that ecto-5'NT has diagnostic value in T cell malignancies and may be aberrantly expressed in some cases of ATL and CTCL.

5'-Nucleotidase↗
PubMed1989

A kinetic analysis of lymphocyte 5'-nucleotidase in B-cell clones from control subjects and patients with primary hypogammaglobulinaemia.

The affinity of lymphocyte 5'-nucleotidase (5NT) for its substrate adenosine monophosphate (AMP) was studied in Epstein-Barr virus immortalized B-lymphocyte clones from healthy controls and patients with primary hypogammaglobulinaemia. Km values for AMP for 5NT in most of the patient clones were found to be significantly increased compared to B-cell clones from normal subjects, whereas Vmax values were within the normal range.

5'-Nucleotidase↗
PubMed1986

Alkaline phosphatase and 5'-nucleotidase enzymes in the carotid rete-cavernous sinus complex of sheep and goats.

12 sheep and 4 goats were used to detect the presence of alkaline phosphatase (A.P.) and 5'-nucleotidase (5'-N) enzymes in the carotid rete-cavernous sinus structure. Different methods of preservation were used. The calcium and the lead methods were used to detect the presence of A.P. and 5'-N, respectively. Best results in their detection were obtained with liquid nitrogen preservation. A.P. enzyme was found in and around areas in which blood capillaries were present, indicating active transport of materials through the capillary membrane. Slight enzymatic activity was seen on the endothelial surface of the rete branches, while the enzyme seemed to be absent from the cavernous sinus. 5'-N was discernible in the tunica adventitia and in the endothelial cells, while the tunica media of the rete branches was apparently devoid of this enzyme. Possible role of these enzymes in the vascular wall metabolism of this structure has been discussed.

Alkaline Phosphatase↗
PubMed1987

(2')3',5'-Bisphosphate nucleotidase.

(2')3',5'-Bisphosphate nucleotidase has been prepared in electrophoretically homogeneous form from guinea pig liver. The enzyme catalyzes the hydrolysis of the 2'- or 3'-phosphate from the appropriate nucleoside 2',5'- and 3',5'-bisphosphates and is active with 3'-phosphoadenosine 5'-phosphosulfate and with coenzyme A but not with ATP. The 40,000-dalton protein is a monomer that requires Mg2+ for activity.

Adenosine Triphosphate↗
PubMed1979

5'-Nucleotidase of L 1210 cells. Cytochemical and kinetic studies.

The activity of 5'-nucleotidase in L 1210 leukaemia cells fixed in situ by glutaraldehyde was established by electron microscopic cytochemistry and biochemical assays. The enzyme activity is localized uniquely on the cell surface. In biochemical assays the time course of phosphate liberation by the suspension of glutaraldehyde fixed cells was linear up to 15 min incubation. The activity was proportional to the number of cells in the suspension, amounting of 0.019 units activity per 10(8) cells.

Animals↗
PubMed1979

Histochemical studies for 5'-nucleotidase and alpha-naphthyl (non-specific) esterase in lymphocytes from patients with primary immunoglobulin deficiencies.

Lymphocytes from patients with primary immunodeficiency were tested histochemically for ecto 5'-nucleotidase (5'N) and alpha-naphthyl (non-specific) esterase. More than half the patients with 'common variable' hypogammaglobulinaemia, all those with X-linked hypogammaglobulinaemia and some of those with selective IgA deficiency had a very low percentage of lymphocytes staining for 5'N as compared to controls. A lack of B cells probably explains the finding in X-linked hypogammaglobulinaemia, but does not fully explain the results in the other groups. Most patients with 'common variable' hypogammaglobulinaemia had a very low percentage of lymphocytes with granular staining for alpha-naphthyl (non-specific) esterase in contrast to normal numbers in those with X-linked hypogammaglobulinaemia and most of those with selective IgA deficiency. Granules containing non-specific esterase are characteristically found in 'mature' T lymphocytes. The enzyme abnormalities in the T and B cells of 'common variable' hypogammaglobulinaemic patients could be explained by 'immature' cell types.

Adolescent↗
PubMed1977

Haemolytic anaemia due to erythrocyte pyrimidine 5'-nucleotidase deficiency. Report of the first South African family.

The first South African case of haemolytic anaemia due to erythrocyte pyrimidine 5'-nucleotidase deficiency is reported. The anaemia is characterized by the presence of high erythrocyte pyrimidine nucleotide levels and marked basophilic stippling. The enzyme levels in 20 family members confirm an autosomal recessive mode of inheritance and illustrate the difficulty of diagnosing the carrier state.

Anemia, Hemolytic↗
PubMed1980

[Influence of thyroid condition on 5'-nucleotidase activity of the plasma membrane in the rat liver].

The effect of thyroid hormones on the Kinetic properties of plasmatic membrane 5'-nucleotidase in rat liver is studied. The Vmax and Km which increased significatively a week after thyroidectomy were reported to the normal values by the chronic administration of T3. The decrease in Vmax and Km observed five weeks after thyroid ablation may be attributed to secondary effects occurring with time.

Animals↗
PubMed1980

[Influence of age on the 5'-nucleotidase activity of the plasma membrane of rat liver: note II].

The effect of age on the kinetic properties of the plasma membrane 5'-nucleotidase in liver cells is studied. Vmax and Km and the discontinuity temperature are lower in the 230 +/- 15 days old rats. It appears that lipids do not affect the isotermic kinetic of the enzyme, while the decrease in the discontinuity temperature in the 230 +/- 15 days old animals might be related to the higher percent of insaturated fatty acids.

Age Factors↗
PubMed1980

Lymphocyte 5'-nucleotidase in primary hypogammaglobulinaemia and cord blood.

The 5'-nucleotidase (5'-N) deficiency on circulating mononuclear cells of patients with 'common variable' hypogammaglobulinaemia (CV-H) was shown to be the result of one or more of three factors: reduced T cell 5'-N activity, a reduced percentage of circulating B cells, and a low B cell 5'-N activity. A lack of circulating B lymphocytes, together with a low T cell 5'-N activity in some cases, was found to be responsible for the deficiency of lymphocyte 5'-N in patients with X-linked hypogammaglobulinaemia (X-H). The low levels of 5'-N activity in CV-H and X-H patients were not due to abnormal compartmentalization of the enzyme, altered enzyme kinetics, or the presence of a regulatory factor. Cord Blood B and T cells have a lower 5'-N activity than adult lymphocytes. The patient and cord blood data are discussed in relation to the stage of cellular maturity.

Adolescent↗
PubMed1981

[Comparative evaluation of the diagnostic importance of determining 5-nucleotidase and alkaline phosphatase in the blood serum in liver and biliary tract diseases].

Under examination were 186 patients with diseases of the liver and biliary ducts. In patients with mechanical jaundice resulting from cholelythic disease high indices of the activity of 5-nucleotidase and alkaline phosphatase were revealed in 80--85% of cases, in patients with carcinoma of the head of the pancreas--in 100%. The investigation of these tests and blood serum transaminases in dynamics is of great importance for differential diagnosis of diseases of the liver and biliary ducts manifesting themselves by the jaundice syndrome.

Alanine Transaminase↗
PubMed1978

[Distribution of 5'-nucleotidase in fractions of rat yolk-sac after differential centrifugation and isopycnic sucrose gradient centrifugation].

The 5'-nucleotidase considered as a marker enzyme of the plasma membranes shows a highly specific acitvity in both nuclear and mitochondrial-lysosomal fractions of the rat yolk-sac. In isopycnic sucrose gradient fractionation of the mitchondrial-lysosomal fraction a relative accumulation of this enzyme could be shown in the density level of the phagolysosomes (d = 1,16--1,20).

Animals↗
PubMed1978

[Action of testosterone on 5'nucleotidase activity in the rat epididymal epithelium].

The epididymal epithelium of the rat has a 5'nucleotidasic activity, which is located in the basal cells and in the apical border of the principal cells. After bilateral castration, the pattern of this enzymatic activity is modified, but it is restored by a testosterone treatment. Bilateral castration abolished the apical activity of the epithelium, while the basal cells remained active. However different migratory aspects of basal cells seem to show their participation in the secretory function of the epithelium. Testosterone thus appears as a regulator for the basal cells activity and this would explain its role in the epididymal function.

Animals↗