Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.6.1.2 (alanine aminotransferase)
 26,722 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1 Here we compared the effects of various inhibitors of the activity of protein tyrosine kinase on (i) the expression of the activity of the inducible isoform of nitric oxide (NO) synthase (iNOS) caused by endotoxin (lipopolysaccharide, LPS) in cultured macrophages, (ii) the induction of iNOS and cyclooxygenase 2 (COX-2) protein and activity in rats with endotoxaemia, and (iii) the circulatory failure and organ dysfunction caused by LPS in the anesthetized rat. 2 Activation of murine cultured macrophages with LPS (1 microgram ml-1) resulted, within 24 h, in a significant increase in nitrite (an indicator of the formation of NO) in the cell supernatant. This increase in nitrate was attenuated by the tyrphostins AG126, AG556, AG490 or AG1641 or by genistein in a dose-dependent fashion (IC50: approximately 15 microM). In contrast, tyrphostin A1 (an analogue of tyrphostin AG126) or daidzein (an analogue of genistein) had no effect on the rise in nitrite caused by LPS. 3 Administration of LPS (E. coli, 10 mg kg-1, i.v.) caused hypotension and a reduction of the pressor responses elicited by noradrenaline (NA, 1 microgram kg-1, i.v.). Pretreatment of rats with the tyrphostins AG126, AG490, AG556, AG1641 or A1 attenuated the circulatory failure caused by LPS. Although genistein attenuated the vascular hyporeactivity to NA, it did not affect the hypotension caused by LPS. Daidzein did not affect the circulatory failure caused by LPS. 4 Endotoxaemia for 360 min resulted in rises in the serum levels of (i) urea and creatinine (indicators of renal failure), (ii) alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin and gamma-glutamyl transferase (gamma GT) (indicators of liver injury/dysfunction), lipase (an indicator of pancreatic injury) as well as lactate (an indicator of tissue hypoxia). None of the tyrosine kinase inhibitors tested had a significant effect on the rise i the serum levels of urea, but the tyrphostins AG126, AG556 or A1 significantly attenuated the rises in the serum level of creatinine caused by LPS. In addition, all tyrphostins and genistein attenuated the liver injury/failure, the pancreatic injury, the hypoglycaemia and the lactic acidosis caused by LPS. In contrast, daidzein did not reduce the organ injury/dysfunction or the lactic acidosis caused by LPS. 5 Injection of LPS resulted (within 90 min) in a substantial increase in the serum level of tumor necrosis factor alpha (TNF alpha), which was attenuated by pretreatment of LPS-rats with any of the tyrphostins used. Genistein, but not daidzein, also reduced the rise in the serum levels of TNF alpha caused by LPS. Endotoxaemia for 6 h also resulted in a substantial increase in the expression of iNOS and COX-2 protein and activity in the lung, which was attenuated by pretreatment of LPS-rats with the tyrphostins AG126, AG556 or genistein, but not by daidzein. 6 Thus, tyrphostins (AG126, AG556, AG1641 or A1) and genistein, but not daidzein (inactive analogue of genistein), prevent the (i) circulatory failure, (ii) the multiple organ dysfunction (liver and pancreatic dysfunction/injury lactacidosis, hypoglycaemia), as well as (iii) the induction of iNOS and COX-2 protein and activity in rats with endotoxic shock.
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PMID:Effects of tyrphostins and genistein on the circulatory failure and organ dysfunction caused by endotoxin in the rat: a possible role for protein tyrosine kinase. 929 29

The effects of thyroid hormone deficiency in utero on the fetal glucogenic capacity were investigated by measuring glucose production and hepatic levels of glycogen and gluconeogenic enzymes in normal sheep fetuses in the fed and fasted states during late gestation and in those made thyroid hormone deficient by fetal thyroidectomy (TX). In the fed state, fetal TX had no effect on glucose uptake, utilisation or production by the fetus. It also had no apparent effect on the glycogen content or activities of the key gluconeogenic enzymes in the fetal liver. In addition, fetal plasma concentrations of insulin, cortisol, adrenaline or noradrenaline were unaffected by fetal TX in the fed state. In contrast, the rates of fetal O(2) consumption and CO(2) production per kilogram fetal bodyweight were significantly lower in TX than in intact fetuses in the fed state (P<0.05). TX prevented fetal glucose production in response to maternal fasting for 48 h. It also abolished the normal decreases in the fetal glucose carbon oxidation fraction, the rate of CO(2) production from glucose carbon and in the fraction of the umbilical O(2) uptake used for glucose carbon oxidation that occur during fasting in intact fetuses. At the end of the fast, plasma noradrenaline concentrations and hepatic levels of glycogen, glucose 6-phosphatase, fructose diphosphatase and alanine aminotransferase were significantly lower in TX than in intact fetuses. These observations show that thyroid hormones are essential for glucogenesis in the sheep fetus during late gestation and suggest that these hormones act both on the hepatic glucogenic pathways and on the mechanisms activating glucogenesis in utero.
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PMID:Regulation of glucogenesis by thyroid hormones in fetal sheep during late gestation. 1147 42

An important increase of plasma hormone levels like insulin, TSH and aldosterone was observed in human subjects after space flights, however in the changes of plasma content of ACTH, cortisol, adrenaline and noradrenaline the individual variations were observed in relation to number and duration of space flight. For evaluation of the effects of these changes in plasma hormone levels on metabolic processes also the experiments with small animals subjected to space flights on a board of biosatellite of Cosmos series were running. An elevation of plasma levels of corticosterone, adrenaline, noradrenaline and insulin was found in rats after the space flights of duration from 7 to 20 days. It was demonstrated, that the increase of corticosterone in plasma is followed by the activation of enzymes involved in the amino acid metabolism in rat liver (tyrosine aminotransferase, tryptophanpyrolase, alanine aminotransferase and aspartate aminotransferase). After a short recovery period (2 to 6 days) the plasma corticosterone concentration and also the activity of liver enzymes returned to control levels. The exposition of animals to stress stimuli during this revcovery period showed higher response of corticosterone levels in flight rats as compared to intact controls. The increase of plasma catecholamine levels was not followed by elevation of lipolysis in adipose tissue. This is due to lower response of adipose tissue to catecholamine because a decrease of the stimulation of lipolysis by noradrenaline was observed in animals after space flight. The increase of insulin was not followed by adequate decrease of glucose concentration suggesting a disturbances in glucose utilization similarly as in cosmonauts after a long-term space flight. These results showed that changes in plasma hormone levels, observed after space flight, affected the regulation of metabolic processes in tissues.
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PMID:Effect of space flights on plasma hormone levels in man and in experimental animal. 1153 12

Catecholamines have been demonstrated to possess direct cardiotoxic effects mediated by oxygen free radicals in isolated organ preparations. In order to assess direct cytotoxic properties, the influence of exogenous noradrenaline (norepinephrine, CAS 51-41-2) (10(-6) mol/l) on isolated guinea-pigs cardiomyocytes was examined, in the presence of propranolol (10(-6) mol/l) and phentolamine (10(-6) mol/l) to inhibit adrenoceptor-mediated effects. Cell viability was assessed by morphologic examination (% of striated, rod-shaped cells), before and after a treatment period of 15 and 60 min by the measurement of intracellular enzyme activities in the supernatant of the suspension (lactate dehydrogenase, creatine kinase, aspartate aminotransferase, alanine aminotransferase, glutamate dehydrogenase). The proportion of viable, rod-shaped cardiomyocytes (21.6% +/- 7.6% after preparation, before starting the treatments) significantly decreased over the experimental time (p < 0.05) and, concomitantly, the activity of intracellular enzymes in the supernatant increased. There was no difference between controls and treated suspensions. Thus, there is no evidence for direct toxic effects of norepinephrine in micromolar concentration on isolated cardiomyocytes of guinea-pigs. However, cytoprotective effects by propranolol and/or phentolamine cannot be excluded in this model.
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PMID:Studies of the toxic effects of norepinephrine on isolated cardiomyocytes of guinea-pigs. 1176 87

The effects of salbutamol and norepinephrine on the electrocardiogram (ECG), serum potassium level and enzyme activities were studied in rabbits with hyperkalaemia; norepinephrine and salbutamol may be therapeutically useful. For induction of hyperkalaemia, 300 mM KCl solution was used and then isotonic saline solution containing 6 microg salbutamol and 3.9 microg norepinephrine per ml were administered. Norepinephrine and salbutamol decreased the serum potassium from 7.36 +/- 0.26 and 7.21 +/- 0.31 mmol/L to 5.62 +/- 0.27 and 4.35 +/- 0.33 mmol/L, respectively, and caused the ECG changes (flatness of P wave, widening of QRS complex and bradycardia) to return to the control conditions (time 0). Norepinephrine, but not salbutamol, decreased the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) to the control levels. These results suggest that monitoring of the enzyme activities might be useful as it yields indexes suitable for evaluating the therapeutic approach with norepinephrine in hyperkalaemia.
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PMID:Experimental hyperkalaemia in rabbits: effects of salbutamol and norepinephrine treatments on blood biochemistry and electrocardiography. 1451 61

A 72-year-old woman with von Recklinghausen's disease was referred to our hospital because of pain and muscle weakness in her thighs. She had elevated serum values of creatine kinase, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and aldolase. Based on these results, a diagnosis of polymyositis was made. Treatment with prednisolone improved muscle strength, and laboratory values returned to normal. Computed tomography, magnetic resonance imaging of the abdomen, and 131I-metaiodobenzyl guanidine MIBG scintigraphy demonstrated a tumor 3 cm in diameter in the region of the left adrenal gland. Endocrinologic investigation disclosed elevation of serum and urine catecholamines. Since the blood pressure was normal, nonfunctioning pheochromocytoma was diagnosed clinically. The nonhypertensive course was attributed to reduced vascular response to noradrenaline. Serum lactate dehydrogenase. alkaline phosphatase. and asparate aminotransferase became elevated, and abdominal computed tomography showed a well-defined mass measuring 13 x 12 x 10 cm in the right lobe of the liver. The patient underwent right trisegmentectomy and left adrenalectomy. Histologically the adrenal tumor was a typical pheochromocytoma. The hepatic tumor was a leiomyosarcoma consisting of elongated spindle-shaped atypical cells arranged in intersecting bundles. Immunohistochemically, the cells of this tumor were reactive for alpha-smooth muscle actin and vimentin. The leiomyosarcoma recurred and metastasized to the liver. Eight months after onset of symptom, the patient developed hepatic coma and died. The mean age at presentation with pheochromocytoma in von Recklinghausen's disease patients age is 42 years. Our patient was considerably older. To the best of our knowledge this is the first report of a patient with von Recklinghausen's disease developing polymyositis. asymptomatic pheochromocytoma, and primary hepatic leiomyosarcoma and illustrates the need to remain aware of the possibility of cancer in von Recklinghausen's disease.
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PMID:[A patient with von Recklinghausen's disease associated with polymyositis, asymptomatic pheochromocytoma, and primary hepatic leiomyosarcoma]. 1523 55

This study addressed the question of whether thaliporphine, a phenolic aporphine alkaloid obtained from Chinese herbs and possessing antioxidant and alpha-1 adrenoceptor antagonistic activity, has protective effects in endotoxaemic rats and we attempted to elucidate the mechanisms contributing to such protective effects. Injection of rats with endotoxin (E. coli lipopolysaccharide, LPS) induced severe hypotension and tachycardia as well as vascular hyporeactivity to noradrenaline. Pretreatment of LPS-treated rats with thaliporphine attenuated the delayed hypotension significantly whilst only a higher dose (1 mg/kg) of thaliporphine decreased LPS-induced tachycardia. LPS significantly increased nitric oxide (NO.) and superoxide anion (O(2).(-)) levels, a response that was reduced by pretreatment with 1 mg/kg thaliporphine. Endotoxaemia for 240 min resulted in a bell-shaped time course for the change of serum tumour necrosis factor-alpha (TNF-alpha) level with a peak at 60 min. Pretreatment of LPS-treated rats with 1 mg/kg thaliporphine significantly reduced the serum TNF-alpha level at 60 min. In addition, LPS caused a biphasic change in blood glucose and thaliporphine attenuated the late-phase decrease in blood glucose. Endotoxaemia induced multiple organ injury in the liver, kidney and heart, as indicated by increases of aspartate aminotransferase (GOT), alanine aminotransferase (GPT), creatinine (CRE), lactate dehydrogenase (LDH) and creatine phosphate kinase muscle-brain (CKMB) levels in serum. These increases of biochemical markers and inflammatory cell infiltration into injured tissues were reduced significantly by treatment with thaliporphine. In addition, thaliporphine increased the survival rate of LPS-treated mice dose-dependently. In conclusion, our results suggest that thaliporphine could be a novel agent for attenuating endotoxin-induced circulatory failure and multiple organ injury and may increase the survival rate. These beneficial effects of thaliporphine may be attributed to the suppression of TNF-alpha, NO. and O(2).(-) production.
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PMID:Thaliporphine increases survival rate and attenuates multiple organ injury in LPS-induced endotoxaemia. 1565 98

A total of 44 donor/recipient perioperative and intraoperative variables were prospectively analyzed in 89 deceased-donor liver transplantations classified as initial good graft function (IGGF) or initial poor graft function (IPGF) according to a scoring system based on values obtained during the 1st 72 postoperative hours from the serum alanine aminotransferase (ALT) concentration, bile output, and prothrombin activity. The IGGF compared with the IPGF group showed: 1) longer graft (P = .002) and patient (P = .0004) survival; 2) at univariate analysis, a higher (mean [95% confidence interval]) preharvest donor arterial partial pressure of oxygen (PaO(2)) (152 [136-168] and 104 [91-118] mmHg, respectively; P = .0008) and arterial hemoglobin oxygen saturation (97.9 [97.2-98.7] and 96.7 [95.4-98.0]%, respectively; P = .0096), a lower percentage of donors older than 65 years (13 and 33%, respectively; P = .024), a lower percentage of donors treated with noradrenaline (16 and 41%, respectively; P = .012). At multivariate analysis, IGGF was associated positively with donor PaO(2) and negatively with donor age greater than 65 years and with donor treatment with noradrenaline. Independently from the grouping according to initial graft function, graft survival was longer when donor PaO(2) was >150 mmHg than when donor PaO(2) was < or =150 mmHg (P = .045). In conclusion, preharvest donor hyperoxia predicts IGGF and longer graft survival.
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PMID:Preharvest donor hyperoxia predicts good early graft function and longer graft survival after liver transplantation. 1566 81

We analyzed preoperative factors related to postoperative mortality after liver transplantation among a cohort of 268 consecutive liver transplant patients over 6 years. We studied the impact of 10 recipient variables, 14 donor features, and three operative aspects. We also studied the correlation with death and survival using various predictive scores (Child, Cordoba Score, MELD, and UCLA). Univariate analysis showed that the factors with a significant association with postoperative mortality were the use of noradrenaline in the donor, total ischemia time (>12 hours), and transplant indication (hepatitis C virus versus the rest). Multivariate analysis of mortality showed the impact of female donor sex, recipients over >60 years, recipient albumin less than 2.8, and total graft ischemia time more than 12 hours. Univariate analysis of 1-year survival showed a statistically significant relation with D/R gender similarity, as well as donor GOT (>170) and GPT (>140) values. Multivariate analysis of 1-year survival showed donor GOT (>170) and donor/recipient gender similarity to be significant. Concerning the prediction models, Child-Pugh (AB versus C) best determined postoperative mortality (P < .006), MELD was predictive of 1-year survival (P < .03). The most important variables related to postoperative mortality were total ischemia time over 12 hours, recipient albumin less than 2.8, and age above 60 years. The variable with most impact on 1-year survival was the degree of graft hepatocyte lesion as determined by GOT. The Child-Pugh system is still the best indicator of postoperative mortality, although MELD may also be a good predictor of survival.
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PMID:Preoperative factors and models predicting mortality in liver transplantation. 1586 54

We have investigated how the endothelium affects vascular responses following sub-chronic low dose cyanide administration. Cyanide exists in low levels in cassava foods, which are widely consumed in tropical Africa. Adult rabbits were administered 0.38 mg/kg per day KCN po for 25 days, and responses of the isolated aortic rings to noradrenaline (NA), calcium chloride (Ca2+) and acetylcholine (ACh) were measured in vitro in the presence and absence of the endothelium. In order to establish that the dose was not toxic, animal weight, some haematological indices, plasma alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were measured. Results show that endothelium denudation significantly (P <0.05) attenuates NA-induced contraction in rings from cyanide-treated rabbits. There was a similar reduction in response in Ca2+-depleted NA-precontracted endothelium-denuded aortic rings from cyanide-treated rabbits. Endothelium-denuded rings from cyanide-treated rabbits showed significantly (P <0.05) enhanced relaxation to ACh. In rings from control animals, the responses to NA and Ca2+ were not significantly altered, whether in the presence or absence of the endothelium. There were no significant changes in the studied toxicological indices. We conclude that endothelial compromise is necessary for low-dose sub-chronic cyanide-induced to alter vascular reactivity to NA and ACh.
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PMID:Effects of sub-chronic oral cyanide on endothelial function in rabbit aortic rings. 1737 Aug 68


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