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:3.5.4.4 (adenosine deaminase)
5,136 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 54-year-old male patient was admitted to Osaka University Medical School Hospital for interferon treatment for chronic hepatitis C and the daily administration of recombinant interferon-alpha 2a started at the dose of 9 megaunits per day. Fourteen days later, moderate right pleural effusion was detected by abdominal magnetic resonance imaging study. He had experienced no symptom to suggest pleural effusion or any pulmonary lesions during interferon treatment. The pleural fluid was serous, showing the character of slightly bloody, turbid and positive Rivalta test, and the levels of lactic dehydrogenase and adenosine deaminase were not elevated. His serum titer of anti-nuclear antibody increased to 80 in homogenous staining, but anti-DNA antibody and anti-liver kidney microsome-1 antibody remained negative. Other laboratory tests or physical findings could not satisfy the criteria of any autoimmune diseases, such as systemic lupus erythematosus. After discontinuation of interferon administration, his pleural effusion resolved gradually and disappeared completely by use of no specific drugs. This is the first case that pleural effusion developed during interferon administration without any other clinical signs indicating autoimmune diseases. The increase of serum titer of anti-nuclear antibody prompted us to elucidate that pleuritis might be induced by immunological activation of interferon.
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PMID:Pleural effusion during interferon treatment for chronic hepatitis C. 1110 Mar 69

Adenosine (ADO) is a well-known regulator of a variety of physiological functions in the heart. In stress conditions, like hypoxia or ischemia, the concentration of adenosine in the extracellular fluid rises dramatically, mainly through the breakdown of ATP. The degradation of adenosine in the ischemic myocytes induced damage in these cells, but it may simultaneously exert protective effects in the heart by activation of the adenosine receptors. The contribution of ADO to stimulation of protective effects was reported in human and animal hearts, but not in rat hearts. The aim of this study was to evaluate the role of adenosine A1 and A3 receptors (A1R and A3R), in protection of isolated cardiac myocytes of newborn rats from ischemic injury. The hypoxic conditions were simulated by exposure of cultured rat cardiomyocytes (4-5 days in vitro), to an atmosphere of a N2 (95%) and CO2 (5%) mixture, in glucose-free medium for 90 min. The cardiotoxic and cardioprotective effects of ADO ligands were measured by the release of lactate dehydrogenase (LDH) into the medium. Morphological investigation includes immunohistochemistry, image analysis of living and fixed cells and electron microscopy were executed. Pretreatment with the adenosine deaminase considerably increased the hypoxic damage in the cardiomyocytes indicating the importance of extracellular adenosine. Blocking adenosine receptors with selective A1 and A3 receptor antagonists abolished the protective effects of adenosine. A1R and A3R activation during the hypoxic insult delays onset of irreversible cell injury and collapse of mitochondrial membrane potential as assessed using DASPMI fluorochrom. Cardioprotection induced by the A1R agonist, CCPA, was abolished by an A1R antagonist, DPCPX, and was not affected by an A3R antagonist, MRS 1523. Cardioprotection caused by the A3R agonist, Cl-IB-MECA, was antagonized completely by MRS 1523 and only partially by DPCPX. Activation of both A1R and A3R together was more efficient in protection against hypoxia than by each one alone. Our study indicates that activation of either A1 or A3 adenosine receptors in the rat can attenuate myocyte injury during hypoxia. Highly selective A1R and A3R agonists may have potential as cardioprotective agents against ischemia or heart surgery.
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PMID:Cardioprotective effects of adenosine A1 and A3 receptor activation during hypoxia in isolated rat cardiac myocytes. 1126 59

Biochemical examination of pleural fluid is usually done to try to identify the cause of a pleural effusion. The various analytes that have been suggested for this are reviewed and evaluated. Distinguishing whether the effusion is an exudate or transudate is a pragmatic first step. with further investigations dictated by the clinical features and these results. Total protein and lactate dehydrogenase were used first; Light's criteria were published in 1972 and since then additional markers including cholesterol, bilirubin and albumin gradient plus combinations of these have been proposed. Although combination testing does improve the sensitivity for diagnosis of an exudate. this is at the expense of specificity. Measurement of fluid to serum ratios appears to confer no advantage, and if a single test is required total protein performs as well as any. Additional tests may be useful in specific circumstances: pleural fluid pH may aid decisions over drainage of a parapneumonic effusion; glucose may indicate an effusion associated with rheumatoid arthritis; and adenosine deaminase may help with the diagnosis of tuberculous effusions.
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PMID:Biochemical analysis of pleural fluid: what should we measure? 1147 71

The aim of this study was to define the number of pleural biopsy samples necessary for optimum diagnostic performance and determine to what extent they are complementary. Eighty-four closed pleural biopsies were performed in our department between June 1996 and January 1998 on 55 males and 29 females with an average age of 64.4 +/- 16.7 years. The study of the pleural fluid included: pH, biochemical testing of pleura/serum (proteins, lactate dehydrogenase, glucose, cholesterol, triglycerides, albumin and adenosine deaminase), haemogram, cytology and microbiological testing (Gram-staining, aerobes, anaerobes and mycobacteriae cultures). The biopsies were performed using a Cope needle, with a total of five biopsies for each patient: four for pathological examination (taken numerically in the order in which they were performed: D1, D2, D3 and D4) and one for microbiological testing. In those cases in which the diagnosis was uncertain or effusion persisted, a thoracoscopy or thoracotomy was performed. There were no significant differences in the diagnostic yield of each individual sample (D1, D2, D3 and D4), but there were differences in the sum of the samples, depending on the number of biopsies performed.This was true for total group and the group with carcinomas, but not for the group with tuberculosis. The increase in diagnostic yield with the number of biopsies was more remarkable in the carcinoma cases, where it increased by 35% when four biopsies were performed (54% with one biopsy versus 89% with four biopsies, P < 0.002). In conclusion, the diagnostic yield increased with the number of biopsy samples in the total group and the group with malignancy but not in the group with tuberculous effusions. The best diagnostic performance for malignant pathology was obtained with four samples. In pleural tuberculosis, the diagnostic yield did not increase with more biopsy samples. One high quality sample should be enough to obtain a diagnosis.
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PMID:Determining the optimal number of specimens to obtain with needle biopsy of the pleura. 1186 4

The level of adenosine deaminase (ADA; EC 3.5.4.4) was estimated at different passages in six confluent fibroblast cultures established from forearm skin biopsies of healthy adult normal volunteers. After determination of the zinc concentration in standard growth medium, ADA activity was estimated at different passages of subculture in media with different zinc concentrations. The results indicated that the specific activity of ADA in control confluent skin fibroblast cultures (passage 2) cultivated in standard growth medium containing 15.4 microM zinc (similar to that present in normal human plasma) was equal to 226.6+/-19.64 micromol min(-1) mg(-1) protein. The results showed that there were no significant changes in ADA specific activity in any of the control cultures as the zinc concentration of the medium was increased. To characterize the passage of subculture at which fibroblasts enter the ageing phase, three marker enzymes were assayed namely, phosphofructokinase, lactate dehydrogenase and glycogen phosphorylase. The result showed that the cells enter the ageing phase at passage 20 and beyond. Further investigation showed that ADA activity of serially subcultured confluent cultures cultivated in standard growth medium significantly dropped at passages 20, 25 and 30. ADA activity however was not significantly altered in cells at passage 2, 10 and 15 cultivated in standard growth medium and in the presence of higher zinc levels (23.1, 34.6, 53.8 and 73.1 microM). Furthermore there was significant lowering of ADA activities in cells at passages 20, 25 and 30 when cells were cultured in the presence of 15.4, 23.1 and 34.6 microM zinc. Such lowered activities of ADA were restored to normal when the cells were cultured in the presence of higher zinc concentration equal to 53.8 and 73.1 microM. From the results we concluded that it is possible to restore ADA activity in aged skin fibroblasts to normal levels by raising the zinc concentration in the culture medium to four or five times the control normal plasma zinc level.
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PMID:Changes in adenosine deaminase activity in ageing cultured human cells and the role of zinc. 1291 Apr 82

Among the extrapulmonary presentations of tuberculosis, pleural tuberculosis is the second most frequent. Failure to diagnose and treat pleural tuberculosis can result in progressive disease with involvement of other organs in as many as 65% of patients. Conventional methods such as direct examination of pleural fluid, pleural fluid culture and pleural biopsy have proven to be insufficient for diagnoses of pleural tuberculosis. In this study, we examined a statistical method by combining the diagnostic efficiency of adenosine deaminase activity, pleural fluid protein, lactate dehydrogenase and cellular components in patients with tuberculous pleural effusions. Eighty eight patients over 12 years of age presenting with pleural effusions were included. A positive result by either three of the methods was considered to be indicative of a positive diagnosis of pleural tuberculosis. The determination of adenosine deaminase activity, lactate dehydrogenase levels, and lymphocyte to neutrophil ratio in the pleural fluid yielded a sensitivity of 100% for pleural tuberculosis. A patient was considered positive if any of the three tests was positive, with a specificity of 100%. A positive diagnosis was made when all three tests were positive. Similarly, these different approaches to the combination of pleural adenosine deaminase and lactate dehydrogenase result in sensitivity and specificity of 91.4% and 100% respectively.
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PMID:Simple method for rapid diagnosis of tuberculosis pleuritis: a statistical approach. 1497 37

In a patient with an undiagnosed pleural effusion, the first question to answer is whether the fluid is an exudate or a transudate. This is usually determined by means of Light's criteria, which differentiate transudative effusions from exudative effusions by measuring the levels of total protein and lactate dehydrogenase in the pleural fluid (PF) and serum. In patients under diuretic treatment, Light's criteria misclassify transudates as exudates, but the serum to pleural fluid albumin gradient usually remains above 12 g/L. When tests are done only in PF, protein concentration >30 g/L performs at least as well as the other individual markers. To diagnose tuberculous pleuritis among exudates, PF adenosine deaminase and PF interferon-g exhibit high diagnostic accuracy. When malignancy is suspected the addition of tumour markers to the results of cytologic analysis increases the rate of detection. Other biochemical markers are useful in specific circumstances involving pleural effusion, such as amylase in effusions due to pancreatitis, or oesophageal rupture, and triglycerides in chylothorax. Several PF markers are associated with complicated parapneumonic effusion - e.g. low PF pH and glucose, and high PF LDH activity -- although PF pH appears to be the best biochemical aid in decisions regarding chest tube drainage. Recent reports suggest that neutrophil-derived enzymes (polymorphonuclear elastase and myeloperoxidase) can be useful as early indicators of the need of chest tube insertion; however these findings must be confirmed in large series. This review discusses the clinical usefulness of biochemical markers in the diagnosis and management of pleural effusions. The vast majority of prospective studies in this field have been conducted in adults and, although the mechanisms of pleural effusion production do not differ in children and adults, the prevalence of each etiologic cause does. Therefore it seems advisable to confirm or recalculate the predictive values of each marker in the paediatric population.
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PMID:Useful clinical biological markers in diagnosis of pleural effusions in children. 1498 Feb 72

1. By selectively modifying adenosine metabolism via adenosine deaminase or adenosine kinase inhibitors, it may be possible to enhance the receptor-mediated protective actions of adenosine in a site- and event-specific fashion. 2. We characterized cardioprotective actions of the adenosine deaminase inhibitor erythro-2-(2-hydroxy-3-non-yl)adenine (EHNA) and the adenosine kinase inhibitor iodotubercidin in C57/Bl6 mouse hearts subjected to 20 min global normothermic ischaemia and 40 min reperfusion. 3. Ventricular pressure development only recovered to 45 +/- 2% of baseline levels (67 +/- 5 mmHg) in untreated hearts, with sustained and pronounced diastolic contracture (25 +/- 2 mmHg). Treatment with 20 micromol/L EHNA increased recovery of ventricular pressure (107 +/- 9 mmHg), reduced postischaemic diastolic pressure (13 +/- 1 mmHg) and reduced loss of lactate dehydrogenase (LDH; an indicator of necrotic damage) by 50% (9 +/- 2 vs 19 +/- 2 IU/g). Adenosine kinase inhibition with 10 micromol/L iodotubercidin also improved pressure development (to 100 +/- 8 mmHg) and reduced LDH efflux (5 +/- 2 IU/g). 4. Protective actions were mimicked by adenosine and inhibited by adenosine receptor antagonism (50 micromol/L 8-rho-sulfophenyltheophylline) and mitochondrial K(ATP) channel inhibition (50 micromol/L 5-hydroxydecanoate). 5. Coinfusion of the inhibitors, 'trapping' formed adenosine, failed to exert protection and, in some instances, was detrimental. Although substantial benefit was gained by these agents in hearts from young animals, neither inhibitor was effective in 'aged' hearts (18 months). 6. Our data demonstrate that adenosine deaminase or kinase inhibition substantially limits injury during ischaemia-reperfusion. Protection involves adenosine receptor activation. However, cardioprotection via either enzyme inhibitor requires an alternative purine-salvage pathway to be functional and was reduced in aged hearts known to be increasingly susceptible to ischaemic damage.
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PMID:Protecting murine hearts from ischaemia-reperfusion using selective inhibitors of adenosine metabolism. 1574

Mastoparan, a tetradecapeptide purified from wasp venom, has been shown to stimulate glucose transport in rat adipocytes although the mechanism of its action has remained undefined. Here, we characterized the action of mastoparan on glucose transport in rat adipocytes. Mastoparan at a concentration of 20 microM or more caused a dose-dependent release of lactate dehydrogenase (LDH) from the cells, which closely correlated with its stimulatory effect on glucose uptake. The mastoparan-induced glucose uptake was inhibited neither by deprivation of ATP with KCN nor by addition of phloretin, a direct inhibitor of glucose transporter, suggesting that the ability of mastoparan to stimulate glucose uptake did not derive from activation of the glucose transport system (i.e. translocation or activation of GLUT4 and/or GLUT1). On the other hand, mastoparan at a lower concentration (15 microM or below), which showed an insignificant effect on LDH release, potentiated the insulin action on glucose transport and Akt phosphorylation in the presence of adenosine deaminase. The effect of mastoparan was not additive to that of phenylisopropyladenosine and was completely abolished by pretreatment of adipocytes with pertussis toxin (1 microg/ml for 2 hours). Thus, the present study disclosed duality in the action of mastoparan on glucose uptake in rat adipocytes. At a concentration of 15 microM or less, it enhances the insulin action on glucose transport by a pertussis toxin-sensitive Gi protein-dependent mechanism. At higher concentrations, however, mastoparan increases non-specific permeability of the plasma membrane, which causes LDH release as well as glucose uptake not mediated through glucose transporter.
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PMID:Duality in the mastoparan action on glucose transport in rat adipocytes. 1612 6

In an attempt to differentiate between three important but clinically similar conditions of exudative ascites like tuberculous peritonitis, spontaneous bacterial peritonitis (SBP) and malignant ascites, we evaluated the biochemical parameters of ascitic fluid as a diagnostic aid. The serum ascitic albumin gradient (SAAG), lactate dehydrogenase (LDH), pH, adenosine deaminase(ADA), carcino-embryonic antigen (CEA) and carbohydrate antigen (CA-125) levels were measured in 36 patients with tuberculous peritonitis, 30 patients with SBP and 30 patients with ascites due to malignant disorders. The LDH level was significantly lower in tuberculous peritonitis patients than in malignant and SBP groups. A value of < 110 U/l gave the assay a sensitivity of 94% and a specificity of 93%, positive predictive value of 89% and negative predictive value of 96% for tuberculous peritonitis. The ADA activity was significantly higher in tuberculous peritonitis group than in the other two groups. A cut off value > 33 U/l gave the ADA test a sensitivity of 89%, specificity of 100%, positive predictive value of 100 % and a negative predictive value of 94% for tuberculosis. A pH value of <7.26 with high SAAG (>11 g/l) predicted SBP with reasonable accuracy. Elevated ascitic fluid CEA (>2 ng/ml) and CA - 125(> 35 U/l) was found exclusively in cases of malignant ascites with a single case of tuberculous peritonitis showing CA-125 value > 35 U/l. All these tests are rapid, non-invasive, and easily reproducible and offer good predictive accuracy which is comparable to that of more invasive procedures like peritoneoscopy and biopsy.
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PMID:Study of biochemical parameters of ascitic fluid in exudative ascites with special reference to tuberculous peritonitis. 1691 Mar 22


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