Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:1.11.1.7 (peroxidase)
65,474 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Gallbladder tissue from patients with acute acalculous cholecystitis contains increased amounts of prostanoids when compared to normal gallbladder tissue. Platelet-activating factor (PAF) is a potent stimulus of eicosanoid formation. It has been implicated as a mediator of acute inflammatory processes and systemic responses to shock. In this study the role of PAF in acute acalculous cholecystitis was evaluated. Anesthetized cats underwent gallbladder perfusion with a physiologic buffer solution containing [14C]polyethylene glycol as a nonabsorbable tracer to quantitate mucosal water absorption. Platelet-activating factor was infused into the hepatic artery for 2 hours. Control experiments were performed when vehicle alone was infused. Experiments also were performed when indomethacin was administered intravenously and when indomethacin and PAF were administered. Gallbladder mucosal absorption/secretion and perfusate and tissue prostaglandin E (PGE) and 6 keto prostaglandin F1 alpha (6-keto PGF1 alpha) levels were evaluated. Gallbladder inflammation was evaluated by beta-glucuronidase and myeloperoxidase tissue concentrations and by a histologic scoring system. Platelet-activating factor eliminated gallbladder absorption and produced net fluid secretion associated with dose-related increases in perfusate PGE concentrations and gallbladder tissue PGE and 6 keto PGF1 alpha levels when compared to control values. Platelet-activating factor produced significant inflammation in the gallbladder with increases in the histologic score of inflammation and tissue lysosomal enzyme activities. Indomethacin significantly decreased the fluid secretion, prostanoid levels, and inflammation produced by PAF. The results suggest that PAF may induce acute gallbladder inflammation associated with systemic stress through a prostanoid-mediated mechanism.
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PMID:The role of prostanoids in the production of acute acalculous cholecystitis by platelet-activating factor. 217 43

Purification of monocyte-derived NAP-1/IL-8 by preparative reversed-phase (RP)-HPLC led to the detection of a second peak with polymorphonuclear leukocyte (PMNL)-activating (degranulation, chemotaxis) properties. The monokine responsible for this biological activity, which we tentatively termed NAP-3, could be purified to homogeneity by three different RP-HPLC steps. Tricine-SDS-PAGE analysis gave a single line at Mr 5.3 kD (NAP-1/IL-8 = 5.8 kD). NH2-terminal amino acid sequence analysis read as a major sequence (ASVATELRXCXLQT. .), which shows greater than 40% homology to that of NAP-1/IL-8. The sequence is identical to that found for the 13-kD moiety of melanoma growth stimulating activity (MGSA) and the product of the oncogene gro. Determination of neutrophil chemotactic activity of NAP-3 revealed a typical bell-shaped dose-response curve (ED50 = 2 ng/ml) with no significant neutrophil chemotactic activity at doses greater than 200 ng/ml. Also, in cytochalasin B-pretreated PMNL, NAP-3 elicited release of myeloperoxidase and beta-glucuronidase. Crossdesensitization studies in PMNL enzyme release revealed crossreactivities with the NAP-1/IL-8-R on PMNL. NAP-3 (MGSA/gro) appears to represent the first member of the novel supergene family of beta-thromboglobulin-like host defense cytokines, which expresses both mitogenic as well as proinflammatory properties at the nanogram level.
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PMID:Lipopolysaccharide-stimulated human monocytes secrete, apart from neutrophil-activating peptide 1/interleukin 8, a second neutrophil-activating protein. NH2-terminal amino acid sequence identity with melanoma growth stimulatory activity. 218 61

Ovine neutrophils were isolated and characterised by their morphology, biochemical and functional responses. Two major granule types were observed, peroxidase positive and peroxidase negative, which were identified as the ovine equivalent of the human azurophil and specific granules respectively. A third type of granule identified, which was present at low frequency and was peroxidase negative, was possibly the ovine equivalent of the bovine large granule. Superoxide production following stimulation with PMA, A23187, PAF, ConA and opsonized zymosan (ZC), was 20-50% less, compared to bovine and human neutrophils. Coincubation of PMA with either PAF or A23187 enhanced superoxide production by 4 to 5 fold above that of the latter stimulants alone. The amount of beta-glucuronidase was similar to, while myeloperoxidase was more than twice that found in bovine neutrophils. Vitamin B12 binding protein was found in very small amounts, compared to that of bovine or human neutrophils. It was observed that coincubation of PMA with PAF, or A23187 resulted in an inhibition of beta-glucuronidase secretion and an enhancement of myeloperoxidase secretion, respectively. Phagocytic capability of ovine neutrophils was found to be optimal at a neutrophil to ZC ratio of 1:10, and which corresponded with an enhanced myeloperoxidase secretion.
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PMID:Functional and biochemical properties of ovine neutrophils. 233 92

Female BALB/cJ (resistant), C3H/HeJ (intermediate resistant), and C3H/HeDub (susceptible) inbred mice, 4-5 wk old, were infected with Taenia taeniaeformis. Liver sections were stained for the enzymes acid phosphatase, beta-glucuronidase, and peroxidase. Eosinophils present around the parasite were identified by the ethanolic Congo red method. Possible gross changes in lipid metabolism in the hepatocytes surrounding the parasite were investigated with the Sudan black B method. The results of observations made by light microscopy were: (1) beta-glucuronidase activity above background levels was observed only in the hepatocytes around the parasite in BALB/cJ mice at 4, 5, and 6 days postinfection (PI); no reaction was observed in the other 2 strains of mice studied; (2) acid phosphatase activity was very strong at 2, 3, and 4 in the 3 strains of mice while this reactivity was weak at 5 and 6 days PI; (3) the cytoplasm of the hepatocytes around the metacestode stained more heavily with Sudan black B than other hepatocytes; and (4) the presence of eosinophils appearing at 3 days PI around the parasite in all 3 strains of mice was demonstrated by staining with Sudan black B, the substrate of peroxidase, and Congo red. Infected C3H/HeJ and BALB/cJ mice had higher numbers of liver eosinophils than infected C3H/HeDub mice throughout the observation time. The present results suggest 2 conclusions: (1) a parasite-liver interaction occurs as is evident by hepatocyte changes in beta-glucuronidase activity and Sudan black B staining, and (2) resistance to the early stages of T. taeniaeformis is associated with the appearance of eosinophils.
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PMID:Taenia taeniaeformis: early inflammatory response around developing metacestodes in the liver of resistant and susceptible mice II. Histochemistry and cytochemistry. 244 33

Beta-glucuronidase and N-AS-D-chloroacetate esterase cytochemistry have been applied to rat liver sinusoidal endothelial cells and Kupffer cells. Both staining procedures allowed a clear-cut differentiation of either cell type. Kupffer cells which had been stained with beta-glucuronidase showed a positive reaction, whereas sinusoidal endothelial cells were completely negative. If the chloroacetate reaction was used, the former stained diffusely while the latter showed a characteristic granular staining pattern. Identity and purity of sinusoidal endothelial cells and Kupffer cells was validated by transmission and scanning electron microscopy as well as by the pattern of released eicosanoids which is characteristic for either cell type. These two staining techniques are a valuable addition to the peroxidase reaction commonly applied for differentiation.
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PMID:Beta-glucuronidase and chloroacetate-esterase staining discriminates rat liver sinusoidal endothelial cells from Kupffer cells in primary culture. 245 75

Platelet-activating factor (PAF) is a highly active mediator which has been implicated in allergic inflammation and bronchial asthma, possibly by interacting with eosinophils. We have examined the effect of PAF on activation of purified human eosinophils as measured by degranulation (eosinophil peroxidase, eosinophil cationic protein, arylsulfatase B, beta-glucuronidase, and alkaline phosphatase) and oxidative metabolism (superoxide anion production). PAF induced enzyme release at concentrations ranging from 1 pM to 10 microM in a rapid (t1/2 5 to 8 min), Ca2+-dependent and noncytotoxic manner from both the specific and small granules, whereas its biologic precursor and metabolite, lyso-PAF, had no effect. For all enzymes, maximal enzyme release occurred at 100 nM PAF with a mean ED50 value of 1.47 +/- 0.4 nM. At this concentration the mean percentage of total enzyme release by PAF from specific granules was 20.3 +/- 1.6% (17.9% for eosinophil peroxidase, 20.6% for beta-glucuronidase, 22.4% for alkaline phosphatase) and 28.8 +/- 2.2% from small granules (arylsulfatase B). Calcium ionophore A23187, PMA, and opsonized zymosan also induced eosinophil degranulation but their peak effect after 10-min incubation with maximal release 14.7%, 12.9%, or 14.1%, respectively, was lower when compared with PAF. Incubation of eosinophils with the PAF-antagonist WEB 2086 led to a parallel shift of the dose-response curve to the right, indicating a competitive antagonism. PAF also caused generation of superoxide anions by human eosinophils but this occurred at higher concentrations of PAF (1 microM to 30 microM) with an ED50 of 8.4 +/- 0.9 microM. Again, this effect was competitively inhibited by WEB 2086. These studies demonstrate that PAF activates human eosinophils to release granule constituents and generate superoxide anions. Since both PAF and eosinophil products are associated with pathogenesis of bronchial asthma our findings may be of particular pathophysiologic relevance.
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PMID:Stimulation of degranulation from human eosinophils by platelet-activating factor. 254 Nov 98

Neutrophil elastase and myeloperoxidase probably play an important role in the development of pulmonary emphysema. We have analyzed drugs from the major classes of agents that alter neutrophil function to determine if there are drugs in use today that can reduce the load of neutrophil elastase or myeloperoxidase in the lungs of smokers. Eleven representative drugs were tested for their ability to inhibit chemotaxis and degranulation. None of the drugs inhibited chemotaxis in a dose-response fashion at concentrations achievable in human plasma. Sulfinpyrazone, phenylbutazone, and auranofin completely inhibited the release of azurophilic granules (myeloperoxidase) and tertiary granules (beta-D-glucuronidase) when formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) was used as the stimulant, and inhibited azurophilic granule release by 69%, 19%, and 64% respectively, but not tertiary granule release when macrophage-conditioned media was used as the stimulus. In conclusion, none of the drugs tested are inhibitors of chemotaxis; however, three are excellent inhibitors of azurophilic granule enzyme release. Of these three, sulfinpyrazone, a drug that is not currently used clinically for its antiinflammatory effects, is the least toxic and should be considered as a potential drug to reduce the elastase and myeloperoxidase load in the lungs of smokers who are developing emphysema.
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PMID:Search for drugs that may reduce the load of neutrophil azurophilic granule enzymes in the lungs of patients with emphysema. 254 34

Activity of acid phosphatase (AP), beta-glucuronidase (GR), N-acetyl-beta-D-glucosaminidase (GZ), and peroxidase (P) was assessed using a semiquantitative cytochemical method in peritoneal macrophages of 30 patients with end-stage renal failure treated by intermittent peritoneal dialysis and of 30 control patients with normal renal function. The dialysed patients showed a significantly higher activity of GR and P at the beginning of the treatment as compared with the respective activities observed in the control group and a further significant rise of these activities after 4 months of dialysis. Activity of AP at the beginning of the treatment was insignificantly lower than in the control group and the difference became significant at the end of the investigated period. There was no significant difference between the dialysed patients and the control group in the activity of GZ assessed at the beginning of the dialytic treatment and after 4 months of dialysis. A significant decrease in that activity was, however, observed in the course of dialysis.
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PMID:Changes in activity of selected lysosomal enzymes in peritoneal macrophages of renal failure patients on peritoneal dialysis. 256 1

A synthetic peptide, AVLPRSAKEL (LU10), the N-terminal amino acid sequence of chemotactic protein (LUCT/IL-8), showed chemotactic activity to polymorphonuclear leukocytes (PMN) with an ED50 of 5 nM for comparable to that of LUCT. Native LUCT and LU10 specifically induced the phosphorylation of 64 kD protein of PMN, and serine residue in the 64 kD protein was major phosphorylated amino acid. Furthermore, native LUCT enhanced the release of myeloperoxidase and beta-glucuronidase from PMN in the presence of cytochalasin B and FMLP, but LU10 did not. These results strongly suggest that the active site for both chemotactic stimulation and 64 kD protein phosphorylation is localized on the sequence of N-terminal 10 amino acids of LUCT.
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PMID:Localization of chemotactic activity and 64 kD protein phosphorylation for human polymorphonuclear leukocytes in N-terminus of the chemotactic protein LUCT/IL-8. 267 39

In order to investigate the availability and release of enzymes from eosinophilic granulocytes in response to a variety of stimuli, guinea pig peritoneal eosinophils were obtained after repeated intraperitoneal injections of freeze-dried Trichinella spiralis larvae. The activities of the enzymes peroxidase, arylsulfatase B, beta-glucuronidase, aminopeptidase, histaminase, cytochrome c oxidase, acid phosphatase, adenosine triphosphatase and glucose 6-phosphatase, and the major basic protein (MBP) were studied histochemically and, in part, also biochemically. Eosinophils were incubated with the following substances: histamine, platelet activating factor, calcium ionophore, compound 48/80, leukotriene B4, prostaglandins E1, and E2, heparin, and eosinophil-chemotactic factors from neutrophils and lymphocytes. Eosinophils displayed a selective and stimulus-dependent enzyme and MBP reaction. Calcium ionophore and compound 48/80 provoked a release of cytotoxic major basic protein, partly associated with peroxidase release, while leukotriene B4 and eosinophil chemotactic factors caused histaminase and peroxidase release and activated leucinaminopeptidase. Heparin and calcium ionophore induced release of both MBP and histaminase. These data support the concept that eosinophils exhibit either inflammatory or cytotoxic, or antiinflammatory properties upon stimulation by various agents.
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PMID:Activation and release of enzymes and major basic protein from guinea pig eosinophil granulocytes induced by different inflammatory stimuli and other substances. A histochemical, biochemical, and electron microscopic study. 275 82


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