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:3.1.26.9 (ribonuclease)
6,589 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the last decades several markers of pancreatic neoplasia have been proposed to obtain a diagnosis as earlier as possible. Prerequisites of a good tumor marker are high sensitivity and specificity. Among the various substances, serum determination of pancreatic enzymes has been found of no utility in early diagnosis of pancreatic cancer, due to its lack in sensitivity and specificity. Similar results with ribonuclease and deoxyribonuclease. Oncofetal antigens (CEA and POA) have been initially considered promising indices; however, further studies showed their limits. In particular CEA is greatly influenced by the presence of hepatic metastases; therefore, serum levels are detectable only in advanced stages. TPA is characterized by a high sensitivity, but lacks in specificity and its use is now avoided. A real progress in the field of tumor markers has been made in the last years with the monoclonal antibody technique: among them CA 19-9 showed a good sensitivity and a satisfactory specificity as regards the diagnosis of pancreatic cancer. However, it cannot be considered as absolute aid, since it is influenced by several factors, as tumor spread, jaundice and liver dysfunction.
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PMID:[Value and limitations of neoplasm markers in the diagnosis of pancreatic carcinoma]. 204 59

To establish the chemical composition of the arsenic inclusion, freshly isolated preparations of inclusions and epon-embedded thin sections of inclusions were subjected to ultrastructural cytochemical analysis. Intranuclear inclusions are composed of amorphous, arsenic-containing subunits aligned linearly to form a coiled complex. Lipase, ribonuclease, deoxyribonuclease, trypsin, pepsin, protease, amylase, or ethylenediaminetetraacetic acid (EDTA) was used to digest or chelate these inclusions. Following enzymatic digestion or chelation, the electron opacity of inclusions was compared with that of control sections exposed for equal times to equivalent solutions lacking the enzymes. Exposure to amylase caused a consistent reduction in the electron opacity of thin sections of inclusions and almost complete digestion of the freshly isolated preparations of inclusions. This was indicative of the presence of a carbohydrate moiety within arsenic inclusions. Incubation of inclusions with EDTA resulted in solubilization of freshly isolated and thin-sectioned embedded material. These data indicated that the intranuclear arsenic inclusion is composed of both metallic and carbohydrate moieties, confirming earlier studies which identified arsenic within inclusions using instrumental neutron activation analysis and X-ray microprobe analysis.
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PMID:Ultrastructural cytochemical analysis of intranuclear arsenic inclusions. 244 99

We previously demonstrated that pneumococcal extracts contain a highly specific inhibitor of human neutrophil elastase (HNE). We now show that the active inhibitor in these extracts is a high-molecular-weight, heat-stable substance that appears to be RNA, since inhibitory activity of pneumococcal extracts is decreased by incubation with ribonuclease but not by incubation with deoxyribonuclease or proteinase K. Moreover, metabolically labeled ([3H]uridine) pneumococcal RNA, isolated by phenol extraction followed by ethanol precipitation, strongly inhibits HNE. Pneumococcal capsular polysaccharide, although polyanionic, is only weakly inhibitory toward HNE and is not a major source of elastase-inhibitory activity in pneumococcal extracts. On the other hand, the capsule of Haemophilus influenzae type b contains polyribosylribitol phosphate. This highly charged polyanion possesses HNE-inhibitory activity, but only under special circumstances to be discussed below. Pneumococci (type I, type II smooth, type II rough) and H. influenzae (type b) all release HNE-inhibitory activity into their culture medium during growth. By contrast, Klebsiella pneumoniae and Staphylococcus aureus release little (if any) stable HNE-inhibitory activity during growth. We propose that some bacterial pneumonias may spare host tissue because polyanions released by the invading microorganisms (e.g. RNA from autolysing pneumococci) inhibit elastase released from inflammatory neutrophils and thereby modulate accompanying tissue proteolysis. Pneumonias caused by microorganisms that do not release stable polyanionic inhibitors of HNE (e.g., Staphylococcus and Klebsiella) may be correspondingly more injurious to the lung.
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PMID:Inhibition of human neutrophil elastase by bacterial polyanions. 244 47

To clarify the relationship between changes in serum pancreatic enzymes and pathological changes in pancreatic parenchyma, this study was performed by using rat models with acute pancreatitis. The models were rats with edematous and necrotizing pancreatitis. Amylase, lipase, ribonuclease (RNase), and deoxyribonuclease (DNase I, II) in the serum were determined for 48 h after the development of pancreatitis. Amylase and lipase levels rose directly in both pancreatitis groups. These enzymes in the necrotizing pancreatitis group were higher than those in the edematous pancreatitis group, but there was no significant difference. RNase levels also rose markedly, but there was no obvious difference between either of the pancreatitis groups. On the other hand, DNase levels were high in the necrotizing pancreatitis group but low in the edematous pancreatitis group, with significant differences between the two groups, especially in the DNase II levels over a 36-h period (p less than 0.05-0.01). Therefore, these results suggest that serum DNase levels reveal the necrotizing changes in pancreatic parenchyma.
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PMID:Relationship between pancreatic enzymes and pathological changes in the pancreas in acute pancreatitis. The significance of determination of serum deoxyribonuclease. 247 54

Quantitatively much higher Concanavalin A (Con. A) agglutinability, haemolytic potency, and activities of acid hydrolases, namely phosphatase (EC 3.1.3.2), ribonuclease (EC 2.7.7.16), deoxyribonuclease (EC 3.1.4.5) and proteinase--were observed in a virulent strain of Entamoeba histolytica (IP-106), as compared to attenuated and avirulent strains (200-NIH) and DKB respectively. In addition, significant differences in these parameters were observed among clonal cultures derived from the latter two cultures by cultivation of single amoebic cells picked out by micromanipulation. Repeated sub-culturing of parent cultures of both these strains in cholesterol-enriched medium resulted in marked enhancement of all the above activities, but no such change occurred in the derived clonal cultures following similar cholesterol treatment. The implication of these findings in relation to enhancement of the virulence of E. histolytica by cholesterol is discussed.
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PMID:Evidence for selection of virulent sub-populations of Entamoeba histolytica by cholesterol. 255 3

The present studies were conducted to identify factors in human purulent material that might limit or enhance the activity of ciprofloxacin against bacteria causing suppurative infection. Ciprofloxacin, imipenem, and ampicillin were tested with regard to binding or inactivation by pus. The bactericidal activity of ciprofloxacin and imipenem were tested against Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, or Staphylococcus aureus in human pus with a pH of 6.0 incubated at 37 degrees C under aerobic or anaerobic conditions. The effect of single or combination drug therapy with 20 mg/kg of ciprofloxacin, imipenem, or rifampin given every 12 hours was tested against E. coli or P. aeruginosa in polymicrobic murine abscesses that had been produced by subcutaneous injection of either of those organisms mixed with Bacteroides fragilis and autoclaved human stool. Antibiotic levels and the number of bacteria surviving in pus were quantitated. Therapy of subcutaneous abscesses was delayed 72 hours to test drug efficacy against organisms in well-established infections. Levels of ampicillin, imipenem, or ciprofloxacin were reduced from 10 micrograms/ml to 3.1 +/- 4.0, 2.7 +/- 3, or 5.8 +/- 2 micrograms/ml, respectively, after incubation in eight pus specimens for 24 hours at 37 degrees C. Ampicillin levels were reduced to less than 1 microgram/ml in four pus specimens containing beta-lactamase. Imipenem levels were undetectable in two specimens and were 0.2 micrograms/ml in one specimen. Ciprofloxacin binding to pus supernate or sediment appeared to be explained by its binding to the deoxyribonucleic acid (DNA) present in pus. Activity of 5 micrograms/ml of ciprofloxacin against four E. coli or K. pneumoniae strains in pus in vitro was greater than that of twofold higher concentrations of imipenem. The bactericidal activity of ciprofloxacin and imipenem were comparable but substantially reduced against S. aureus and P. aeruginosa in pus. Ciprofloxacin alone or regimens combining ciprofloxacin with rifampin or rifampin plus imipenem reduced the number of E. coli in polymicrobic subcutaneous abscesses but had little effect on P. aeruginosa in polymicrobic abscesses. The anaerobic abscess milieu appeared to inhibit the growth of P. aeruginosa. Ciprofloxacin activity in abscess fluid did not appear to be adversely affected by acid pH, aerobic or anaerobic conditions of incubation, the abscess constituents, or the binding of ciprofloxacin to the DNA in pus. Ciprofloxacin was bound to DNA of bacterial or human origin. Binding by pus was reversible, and binding to DNA extracts of pus was blocked by pretreatment of extracts with deoxyribonuclease but not by pretreatment with ribonuclease.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Effect of the abscess environment on the antimicrobial activity of ciprofloxacin. 258 67

The cytosol of a human glioblastoma cell line (KNS-42) stimulated the growth of both bovine aortic endothelial cells and smooth muscle cells in a dose-dependent manner. The endothelial cell growth activity eluted at an apparent molecular weight of about 30,000 on a Sephadex G-100 column and bound to a heparin-Sepharose column with high affinity to elute at 1.3-1.7 M NaCl. The growth activity was destroyed by heating at 56 degrees C for 30 min, but not by exposure to trypsin, deoxyribonuclease or ribonuclease at 37 degrees C for 30 min. As this factor stimulated the growth of vascular endothelial cells and smooth muscle cells, and vasoproliferative responses in chick embryo chorioallantoic membranes were apparent, this factor may possibly be related to tumor angiogenesis.
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PMID:Endothelial cell growth factor derived from a human glioblastoma cell line and possible association with tumor angiogenesis. 266 83

Extracts of Rad+ and radiation-sensitive (rad) mutants of the yeast Saccharomyces cerevisiae were examined for total Mg2+-dependent alkaline deoxyribonuclease activity and the presence of a nuclease that crossreacts immunologically with an antiserum raised against an endo-exonuclease from Neurospora crassa, an enzyme exhibiting both deoxyribo- and ribonuclease activities. No significant differences were observed in total deoxyribonuclease activity between Rad+ and rad mutants. The antibody precipitable activity, however, was found to be 30%-40% of the total alkaline deoxyribonuclease activity in logarithmically growing Rad+ cells. Extracts of stationary phase cells were lacking in antibody precipitable activity. Using immunoblot methods, a 72 kDa crossreacting protein was identified from logarithmically growing cells that was absent from stationary phase cells. In all radiation-sensitive mutants examined, except rad52, at least 20% of total activity was precipitable. Extracts from logarithmically growing rad52 mutants, including a rad52::LEU2 insertion mutant, exhibited less than 10% of the Rad+ precipitable activity; however, some crossreacting material was detected. Although, the level of endo-exonuclease activity is influenced by the RAD52 gene, it is not the product of this gene. The total deoxyribonuclease and the antibody precipitable endo-exonuclease activities were also followed during meiosis. Unlike the Rad+ strain which had previously been shown to have increased levels of total and immunoprecipitable endo-exonuclease as cells underwent meiosis, the rad52 mutant exhibited no increases in either category of nuclease activity. Given the importance of the RAD52 gene in repair, recombination and mutagenesis, the endo-exonuclease may be a significant component of these processes.
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PMID:An endo-exonuclease activity of yeast that requires a functional RAD52 gene. 283 Apr 67

Biotin-labeled DNA probes for bovine herpesvirus type 1 (BHV-1) were used to detect viral nucleic acids in infected cell cultures and clinical specimens by in situ hybridization. Hybridization signal was detected 2 hours after inoculation in the cytoplasm of infected cells, presumably representing input virus. Hybridization was first detected in the nucleus at 4 hours after inoculation; by 10 hours after inoculation, hybridization signal was detected in both nucleus and cytoplasm of almost 50% of the cells. By 15 hours after inoculation, 95% of the cells were positive. Treatment of specimens with ribonuclease or deoxyribonuclease before hybridization allowed clear differentiation of virus-specified DNA and RNA within infected cells. The BHV-1 nucleic acid sequences were detected in nasal epithelial cells obtained from inoculated calves. Since in situ hybridization provides a rapid technique for the detection of BHV-1-specified nucleic acid sequences, it should facilitate studies on the replication, pathogenesis, and diagnosis of BHV-1 infections.
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PMID:Detection of bovine herpesvirus-specific nucleic acids by in situ hybridization with biotinylated DNA probes. 300 5

The clinical association of lupus anticoagulant antibodies with thrombocytopenia and thrombosis was the rationale for investigating the in vitro reactivity of these human hybridoma lupus anticoagulant antibodies with platelets. Fifty human hybridoma antibodies from 13 patients with systemic lupus erythematosus, 2 women with multiple spontaneous abortions, and 4 normal individuals were analyzed for lupus anticoagulant, antiplatelet, anti-DNA, and antiphospholipid reactivities. Of the hybridoma antibodies studied, 25 had lupus anticoagulant activity, 21 had antiplatelet reactivity, and 7 of these antibodies had both lupus anticoagulant and antiplatelet properties. No correlation was found between lupus anticoagulant antibody activity and antiplatelet, anti-denatured DNA, anticardiolipin, anti-egg phosphatidylethanolamine, antiphosphatidylserine, antiphosphatidylinositol, and antiphosphatidylcholine reactions. In contrast, antiplatelet activity was strongly correlated with antiphosphatidylethanolamine (rho = 0.761, p less than 0.001), anticardiolipin (rho = 0.748, p less than 0.001), and anti-dDNA (rho = 0.745, p less than 0.001) reactivities. Pretreatment of platelets with deoxyribonuclease, ribonuclease, trypsin, or phospholipases A2 and C resulted in different effects on the binding of individual hybridoma antibodies to platelets, suggesting that antiplatelet antibodies may recognize different epitopes on the platelet membrane. Our data demonstrate that most hybridoma lupus anticoagulant antibodies did not bind directly to platelets in vitro. This suggests that additional serum factors may be required in vivo to explain the association of these antibodies with thrombocytopenia and thrombosis.
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PMID:Lupus anticoagulant and antiplatelet properties of human hybridoma autoantibodies. 311 88


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