Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.5 (5'-nucleotidase)
 3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We evaluated the efficacies of serum catalase (CAT), 5'-nucleotidase (5'NT), and tumor necrosis factor-alpha (TNF) as diagnostic markers of acute graft-vs-host disease (GVHD) in 28 allogeneic bone marrow transplant recipients by comparing their abilities to discriminate between GVHD-related and non-GVHD-related complications. Mean peak serum CAT concentrations for patients with GVHD-related complications (n = 17) were about fivefold higher than concentrations in patients with non-GVHD-related complications (n = 25; P = 0.003), whereas the mean peak concentrations of serum 5'NT and TNF were not substantially different. Similarly, the sensitivity and specificity of serum CAT (100% and 88%, respectively) for use as a diagnostic marker of GVHD were much better than those of serum 5'NT (88% and 24%, respectively) or serum TNF (65% and 4%, respectively). Receiver-operating characteristic plots of all possible sensitivity-specificity pairs obtained over the whole range of results also showed that serum CAT has the best diagnostic accuracy. Low specificities of serum TNF and 5'NT were caused mainly by their increase in septicemia, fungal infection, and veno-occlusive disease and after the use of granulocyte-macrophage colony-stimulating factor to stimulate donor cell engraftment. Serum CAT may prove to be a rapid and relatively noninvasive test for the diagnosis of acute GVHD.
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PMID:Serum catalase as marker of graft-vs-host disease in allogeneic bone marrow transplant recipients: pilot study. 758 45

Freeze-substituted rat liver embedded in glycol methacrylate (GMA) has been used to demonstrate the activities of several enzymes. The following enzymes could be detected in GMA-sections by the indicated histochemical procedure(s): 5'-nucleotidase (lead salt, cerium-diaminobenzidine), alkaline phosphatase (indoxyl-tetrazolium salt), catalase (diaminobenzidine), acid phosphatase (diazonium salt), lactate dehydrogenase (tetrazolium salt) and glutamate dehydrogenase (tetrazolium salt). The activities of all these enzymes were dramatically decreased compared with the activities demonstrated in unfixed cryostat sections, with the exception of catalase. The activities of the following enzymes could not be detected in GMA-sections: glucose-6-phosphate dehydrogenase (tetrazolium salt), xanthine oxidoreductase (tetrazolium salt), D-amino acid oxidase (cerium-diaminobenzidine-cobalt-hydrogen peroxide) and glucose-6-phosphatase (cerium-diaminobenzidine). The possible role of restricted penetration of reagents into the resin was studied by measuring cytophotometrically the enzyme activities in GMA-sections of 3 and 6 microns in thickness. For all the enzymes that could be detected, the 6 microns:3 microns ratio varied from 1.4 to 2.7. An eventual retarded penetration of reagents into the resin was investigated by measuring cytophotometrically the amount of final reaction product during incubation for acid phosphatase and glutamate dehydrogenase activities. In both cases linear relationships without a lag phase were found for the specific enzyme activities with incubation time. Chemical denaturation of proteins or masking of active sites in proteins due to embedding in the resin monomer may be considered to be the main cause of decreased enzyme activities.
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PMID:Quantitative aspects of enzyme histochemistry on sections of freeze-substituted glycol methacrylate-embedded rat liver. 827 44

The effect of storage of unfixed cryostat sections from rat liver for 4 h, 24 h, 3 days and 7 days at -25 degrees C was studied on the activities of lactate dehydrogenase, glucose-6-phosphate dehydrogenase, xanthine oxidoreductase, glutamate dehydrogenase, succinate dehydrogenase (all demonstrated with tetrazolium salt procedures), glucose-6-phosphatase (cerium-diaminobenzidine method), 5'-nucleotidase (lead salt method), dipeptidyl peptidase II, acid phosphatase (both simultaneous azo coupling methods), D-amino acid oxidase (cerium-diaminobenzidine-cobalt-hydrogen peroxide procedure) and catalase (diaminobenzidine method). The effect of drying of the cryostat sections at room temperature for 5 and 60 min was investigated as well. The enzyme activities were quantified by cytophotometric measurements of test and control reactions. The test minus control reaction was taken as a measure for specific enzyme activity. It was found that the activities of all the enzymes investigated, with one exception, were affected neither by storage of the cryostat sections at -25 degrees C for up to 7 days, nor by drying of the sections at room temperature for up to 60 min. The exception was xanthine oxidoreductase, whose activity was reduced by 20% after 5 min drying of sections or after 4 h storage. Therefore, only incubations for xanthine oxidoreductase activity have to be performed immediately after cutting cryostat sections, whereas for the other enzymes a considerable margin appears to exist.
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PMID:The effects of storage on the retention of enzyme activity in cryostat sections. A quantitative histochemical study on rat liver. 846 85

Activities of adenosine deaminase, 5'-nucleotidase, xanthine oxidase, superoxide dismutase, glutathione peroxidase and catalase enzymes were measured in cancerous and non-cancerous adjacent colorectal tissues from 10 patients. Activities of DNA turn-over enzymes (ADA, 5'NT and XO) were found increased and those of free-radical metabolizing enzymes (SOD, GSH-Px and CAT) decreased in cancerous tissues compared with those of non-cancerous adjacent ones. Malondialdehyde (MDA) concentrations in cancerous tissues were also found higher than those of non-cancerous tissues, which indicated accelerated lipid peroxidation in the cancerous tissues. In the correlation analysis, disordered enzymatical relations were observed between the enzymes of both metabolic pathways. Results suggest that activities of purine metabolizing enzymes increase to cope with accelerated purine metabolism in cancerous tissues and, enzymatic antioxidant defense potential of cancerous tissues decreases due to carcinogenic processes in the tissues. Reduced antioxidant defense system makes the cancerous tissue more vulnerable to toxic effects of some free-radical species.
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PMID:Activities of the enzymes participating in purine and free-radical metabolism in cancerous human colorectal tissues. 992 74

5'-Nucleotidase, responsible for the conversion of adenosine-5'-monophosphate into adenosine, was purified from bovine brain membranes, and subjected to oxidative inactivation. The 5'-nucleotidase activity decreased slightly after the exposure to either glutathione or Fe2+. The glutathione-mediated inactivation of 5'-nucleotidase was potentiated remarkably by Fe2+, but not Cu2+, in a concentration-dependent manner. Similarly, glutathione exhibited a concentration-dependent enhancement of the Fe2+-mediated inactivation. In comparison, the glutathione/Fe2+ system was much more effective than the ascorbate/Fe2+ system in inactivating the enzyme. In support of an intermediary role of superoxide ions or H2O2 in the action of glutathione/Fe2+ system, superoxide dismutase and catalase expressed a substantial protection against the inactivation by the glutathione/Fe2+ system. Meanwhile, hydroxyl radical scavengers such as mannitol, benzoate or ethanol were incapable of preventing the inactivation, excluding the participation of extraneous hydroxyl radicals. Whereas adenosine 5'-monophosphate as substrate exhibited a modest protection against the glutathione/Fe2+ action, a remarkable protection was expressed by divalent metal ions such as Zn2+ or Mn2+. Structure-activity study with a variety of thiols indicates that the inactivating action of thiols in combination with Fe2+ resides in the free sulfhydryl group and amino group of thiols. Overall, thiols, expressing more inhibitory effect on the activity of 5'-nucleotidase, were found to be more effective in potentiating the Fe2+-mediated inactivation. Further, kinetic analyses indicate that Fe2+ and thiols inhibit the 5'-nucleotidase in a competitive or uncompetitive manner, respectively. These results suggest that ecto-5'-nucleotidase from brain membrane is one of proteins susceptible to thiols/Fe2+-catalyzed oxidation, and the oxidative inactivation may be related to the selective association of Fe2+ and thiols to the enzyme molecule.
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PMID:Oxidative inactivation of brain ecto-5'-nucleotidase by thiols/Fe2+ system. 1107 66

Administration of aflatoxin B1 to rats (2 mg/kg intraperitoneally) caused significant increase in the activities of gamma-glutamyl transpeptidase, 5'-nucleotidase, acid phosphatase, acid ribonuclease as well as content of lipid peroxides in liver after six weeks. However, the activities of succinate dehydrogenase, glucose-6-phosphatase, catalase, superoxide dismutase, glutathione-S-transferase, glutathione peroxidase and glutathione reductase in liver were decreased. The levels of glycogen and reduced glutathione were also decreased. There were significant elevations in the levels of serum transaminases, phosphatases (acid and alkaline), dehydrogenases (sorbitol, lactate and glutamate) and bilirubin following aflatoxin B1 administration. Picroliv (25 mg/kg/day orally for six weeks), an iridoid glycoside isolated from the roots and rhizomes of Picrorhiza kurroa, significantly prevented the biochemical changes induced by aflatoxin B1.
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PMID:Biochemical changes induced in liver and serum of aflatoxin B1-treated male wistar rats: preventive effect of picroliv. 1116 62

The purpose of this study was to determine whether superoxide anions (O.) activate 5'-nucleotidase (5'-ND), thereby increasing the production of renal adenosine and regulating renal function. Using HPLC analysis, we found that incubation of renal tissue homogenate with the O. donor KO(2) doubled adenosine production and increased the maximal reaction velocity of 5'-ND from 141 to 192 nmol. min(-1). mg protein(-1). The O.-generating system, xanthine/xanthine oxidase increased the maximal reaction velocity of 5'-ND from 122 to 204 nmol. min(-1). mg protein(-1). Superoxide dismutase (SOD) with catalase produced a concentration-dependent reduction of 5'-ND activity in renal tissue homogenate, while the SOD inhibitor diethyldithiocarbamic acid significantly increased 5'-ND activity. Inhibition of disulfide bond formation by thioredoxin or thioredoxin reductase significantly decreased xanthine/xanthine oxidase-induced activation of renal 5'-ND. In in vivo experiments, inhibition of SOD by diethyldithiocarbamic acid (0.5 mg. kg(-1). min(-1) iv) enhanced renal vasoconstriction induced by endogenously produced adenosine and increased renal tissue adenosine concentrations under control condition and in ischemia and reperfusion. We conclude that oxidative stress activates 5'-ND and increases adenosine production in the kidney and that this redox regulatory mechanism of adenosine production is important in the control of renal vascular tone and glomerular perfusion.
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PMID:Oxidative stress enhances the production and actions of adenosine in the kidney. 1170 65

A method for the isolation and purification of plasma membranes of Dictyostelium discoideum by equilibrium centrifugation on sucrose followed by Renografin continuous density gradients has been developed and monitored both with electron microscopy and a number of enzyme assays. On electron microscopy, the final plasma membrane fractions are judged to be freethe basis of of nuclei, rough endoplasmic reticulum, lysosomes and peroxisomes. Some profiles of the mitochondrial inner membranes are found within the plasma membrane fractions, but this contamination has been estimated to be only 5%. On the basis on enzyme assays, the plasma membrane fractions contain all the 5'-nucleotidase activity in the final gradients and are free of catalase, acid phosphatase and malate dehydrogenase activity (markers for peroxisomes, lysosomes, soluble enzymes and the matrix of mitochondria). Their content of glucose-6-phosphatase is reduced by more than 70%. The large majority of RNA and DNA have been removed from the preparation.
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PMID:The involvement of the plasma membrane in the development of Dictyostelium discoideum. I. Purification of the plasma membrane. 1625 Mar 37

Oxidative stress is implicated in the pathogenesis of diabetes mellitus. Selenium supplementation has some benefits in experimental models of diabetes mellitus. This study evaluated whether dietary diphenyl diselenide, a simple synthetic organoselenium compound with antioxidant properties, reduces the streptozotocin (STZ)-induced toxicity. STZ-induced diabetic rats were fed with either standard and diphenyl diselenide (10 ppm) supplemented diets. In experimental trials, dietary diphenyl diselenide significantly decreased mortality rate (p<0.05) induced by STZ treatment. No correlation between this effect and glycemic levels were found. Diphenyl diselenide intake also promoted an increase in vitamin C, -SH levels (liver, kidney and blood) and in catalase (liver and kidney) activity, which were decreased in STZ-treated rats. In enzyme assays, diphenyl diselenide supplementation caused a significant improvement in platelets NTPDase and 5'-nucleotidase activities in STZ-induced diabetic rats when compared to the control and diabetic groups (p<0.05). Nevertheless, this supplementation did not modify the inhibition induced by STZ in delta-ALA-D activity. Our findings suggest that diphenyl diselenide compound showed beneficial effects against the development of diabetes by exhibiting antioxidant properties.
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PMID:Dietary diphenyl diselenide reduces the STZ-induced toxicity. 1787 Feb 24

Chemoprevention has emerged as a very effective preventive measure against carcinogenesis. Several bioactive compounds present in fruits and vegetables have revealed their cancer curative potential on benzo(a)pyrene (B(a)P) induced carcinogenesis. In the present study, the efficacy of quercetin on the level of lipid peroxides, activities of antioxidant enzymes and tumor marker enzymes in B(a)P induced experimental lung carcinogenesis in Swiss albino mice was assessed. In lung cancer bearing animals there was an increase in lung weight, lipid peroxidation and marker enzymes such as aryl hydrocarbon hydroxylase, gamma glutamyl transpeptidase, 5'-nucleotidase, lactate dehydrogenase and adenosine deaminase with subsequent decrease in body weight and antioxidant enzymes-superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, glutathione reductase, reduced glutathione, vitamin E and vitamin C. Quercetin supplementation (25 mg/kg body weight) attenuated all these alterations, which indicates the anticancer effect that was further confirmed by histopathological analysis. Overall, the above data shows that the anticancer effect of quercetin is more pronounced when used as an chemopreventive agent rather than as a chemotherapeutic agent against B(a)P induced lung carcinogenesis.
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PMID:The effects of quercetin on antioxidant status and tumor markers in the lung and serum of mice treated with benzo(a)pyrene. 1805 10


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