Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.5 (thrombin)
 33,306 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The role of platelet aggregation and coagulo-fibrinolytic systems in thrombogenesis of lactic acid-induced pulmonary thrombosis in rat were studied using an anti-coagulant, platelet aggregation inhibitor, fibrinolytic or anti-fibrinolytic agents. In normal rat, heparin (2.5 mg/kg), acetylsalicylic acid (30 mg/kg) and tranexamic acid (100 mg/kg) suppressed specifically coagulation, platelet aggregation induced by collagen or thrombin and fibrinolysis respectively. Urokinase (10,000 units/kg) activated powerfully fibrinolytic system in addition to suppressing slightly platelet aggregation. The pretreatment with heparin, acetylsalicylic acid or urokinase markedly prevented the formation of thrombus initiated by the infusion of lactic acid at the doses used. Additive effect was also obtained by combined administration of these agents. On the other hand, it was interesting to note that tranexamic acid (100 mg/kg) did not affect the thrombus formation at all despite a potent anti-fibrinolytic effect of this agent. These results indicate that both platelet aggregation and enhancement of coagulation activity are important factors responsible for the formation of thrombi in DIC, while the fibrinolytic activity in blood seems not to be involved in it. On the basis of the findings, mechanism for triggering activation of coagulation and platelet aggregation is also discussed here.
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PMID:Patho-physiological studies on lactic acid-induced pulmonary thrombosis in rat. I. Effect of heparin, acetylsalicylic acid, urokinase and tranexamic acid. 118 8

1. North American poisonous snakes have a wide spectrum of complex venoms. 2. Venom, especially that of the rattlesnakes, may cause a variety of hemostatic abnormalities by directly, yet only partially, cleaving fibrinogen, activating the fibrinolytic system, or activating and clearing platelets through the action of proteolytic enzymes. 3. Because these venoms do not result in the generation of thrombin, the syndrome is distinct from true DIC. Bleeding or thrombosis is rare. 4. As thrombin generation remains intact, hemostasis is largely preserved despite dramatic changes in hemostatic tests. 5. Therapy with heparin, blood, or blood products is rarely indicated. 6. Therapy with antivenin in selected cases is logical and efficacious.
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PMID:Hemostatic aspects of envenomation by North American snakes. 140 81

In order to elucidate the activation of the coagulation cascade in patients with malignant neoplasms, we measured the levels of plasma prothrombin fragment F1 + 2, which is liberated in the process of thrombin generation. Twenty healthy adults (Group A), 29 patients with malignancies not complicated with DIC (Group B) and 4 patients with DIC (Group C) were evaluated. The values of F1 + 2 in Group C (2.38 +/- 0.55 nmol/l) were significantly higher (p < 0.01) than those in Group A (0.52 +/- 0.19 nmol/l) and B (0.86 +/- 0.68 nmol/l). Many patients in Group B showed higher levels of F1 + 2 compared to normal subjects, however, no significant differences were found between Group A and B. With respect to other coagulation molecular markers such as TAT, D-Dimer and PIC, F1 + 2 levels revealed positive correlation to those levels. Concerning the clinical course of DIC, elevated levels of F1 + 2 normalized much rapidly than those of TAT and D-Dimer by continuous administration of heparin. In conclusion, the measurement of plasma F1 + 2 is important in monitoring the activation of coagulation system in patients with malignancies, especially with respect to early detection and treatment of DIC.
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PMID:[Evaluation of hypercoagulable state in patients with malignancies by using prothrombin fragment F1 + 2]. 146 81

We measured concentrations of the natural anticoagulant protein C; its cofactor, protein S; and the carrier protein C4b-binding protein (C4BP), in 24 patients with severe infection and 13 with septic shock. Decreased antithrombin III levels were found in 16 of 24 infection patients and all shock patients; high thrombin-antithrombin (TAT) complexes were present in 16 of 24 infection and 12 of 13 shock patients. Protein C concentrations were significantly reduced compared to healthy blood donors, to 60 +/- 14% (infection) and 47 +/- 20% (septic shock) (mean +/- 1 SD). Total protein S levels were not reduced (119 +/- 36.7 and 88 +/- 20.0%, normal value 96 +/- 15%). Free protein S was also normal (27 +/- 9.4 and 30 +/- 8.7%, normal value 29 +/- 9%). The percentage free of total protein S was normal in shock patients (35 +/- 8.5%), but significantly reduced in patients without shock (23 +/- 5.3%). C4BP was significantly higher than normal in the latter group (135 +/- 43%), but not in the shock group (118 +/- 40%), possibly due to increased consumption. Thus, no deficiency of total or free protein S was found in these patients, who had evidence of activated coagulation but no clinical DIC.
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PMID:Protein C, protein S and C4b-binding protein in severe infection and septic shock. 182 15

Both bleeding and thrombosis are commonly seen in newborn infants because of their imbalance of coagulation and fibrinolysis system. In order to clarify some aspects of the hemostatic characteristics during neonatal period, we measured the levels of antithrombin-III (AT-III), thrombin AT-III complex (TAT), alpha 2-plasmin inhibitor (alpha 2PI) and plasmin alpha 2PI complex (PIC) in 137 normal and sick newborn infants. The results were as follows 1) AT-III levels in normal neonates were significantly low as compared with them in normal adults, and further lower levels were found in sick neonates. 2) TAT levels in sick neonates were significantly higher than those in either normal neonates and adults. In sick neonates, the incidence of abnormally high TAT values increased with DIC score points. 3) No significant difference of alpha 2PI level was seen between normal term neonates and adults. However, alpha 2PI levels in sick neonates were significantly low as compared with them in normal term neonates and adults. 4) PIC levels in either normal and sick infants were significantly higher than those in adults, but there was no significant difference in PIC levels between normal and sick newborn infants.
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PMID:[Plasma levels of antithrombin III, thrombin-antithrombin III complex, alpha 2 plasmin inhibitor and plasmin alpha 2 plasmin inhibitor complex in normal and sick newborn infants]. 183 69

Plasma levels of molecular markers of hemostatic activation were investigated in 205 samples from patients with haematopoietic malignancies. These markers included thrombin/antithrombin III complex (TAT), D-dimer, plasmin/alpha 2plasmin inhibitor complex (PIC) and thrombomodulin (TM), and were assayed by EIA methods. Samples were divided into 4 groups according to the level of FDP: group A; FDP 10 greater than, group B; 10 less than or equal to less than 20 group C; 20 less than or equal to less than 40, and group D; less than 40. The mean level of each marker except TM increased in the order of group A, B, C and D. However, in many samples belonging to group A the plasma TAT or PIC levels and both were increased in spite of low FDP level. Furthermore, levels of TAT and PIC in several samples belonging to groups C and D were within the normal range. Also, the mean levels of each marker except TM increased in the order of 2, 3, 4, 5 and over 6 points in DIC score according to the criteria of DIC diagnosis by the research committee on DIC of the Ministry of Health and Welfare in Japan. Eight of the 11 samples (72.7%) obtained from cases with a DIC score of 3 points had high plasma levels of TAT, PIC and D-dimer. Plasma levels of these markers were increased after chemotherapy. These findings lead to the following conclusions: 1) FDP reflexed activation of coagulation and fibrinolysis, but 2) FDP was not more sensitive than TAT and PIC, and 3) the increase of FDP rarely resulted from fibrinogenolysis or non-plasmin mediated fibrinolysis. Furthermore, 4) TAT, D-dimer and PIC may serve as sensitive parameters of hemostatic activation in circulating blood and be valuable markers for early diagnosis of DIC.
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PMID:[Clinical application of laboratory diagnosis: leukemia and DIC]. 183 71

Thrombomodulin (TM) is a constituent glycoprotein of endothelial cell membrane, and soluble TM is present also in plasma and urine. It was revealed by experiments using cultured HUVEC in vitro that TM is released from endothelial cell membrane not with monensin, thrombin, fibroblast growth factor, interleukin-1 or endotoxin, but with H2O2 or endotoxin-treated granulocytes. And the release was suppressed by the coexistence of gabexate mesilate or superoxide dismutase. It was suggested that soluble TM was released from endothelial cell membrane by its injury and digested to multiple molecular forms by endogenous and granulocytic protease(s). TM level in circulation is increased in cases of SLE, MCLS, diabetic angiopathy. It was increased in cases of overt DIC and decreased to the normal level when the patient was recovered from DIC. TM level in circulation was also increased in cases of decompensated liver cirrhosis and markedly in cases of renal insufficiency. It was concluded that plasma TM is a parameter reflecting endothelial injury due to inflammation or metabolic disorders of vascular system. But the interpretation of increased plasma TM was difficult when renal insufficiency was complicated.
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PMID:[Soluble thrombomodulin: a specific parameter of endothelial injury]. 185 Dec 35

The localization of tissue plasminogen activator (t-PA) on microthrombi in various organs of disseminated intravascular coagulation rats (DIC rats) was investigated by using microautoradiographic technique. After the injection of [125I]fibrinogen, experimental DIC rats induced by the infusion of thrombin for 1 h were submitted to microautoradiograms (MARGMs) of some major organs. The radioactivity of [125I]fibrin thrombi, which were observed as silver grains, was localized in the glomeruli and parts of small vessels in the kidney. In the liver, microthrombi were seen in sinusoid vessels and on Kupffer cells. In addition, many microthrombi were noted in small vessels in the lung and marginal zones in the spleen. Two min after the intravenous administration of [125I]t-PA to DIC rats, many silver grains were observed on each MARGM of the kidney, lung, liver and spleen showing the formation of microthrombi. From the identical results with the observations of MARGMs after the injection of [125I]fibrinogen, we confirmed that t-PA was highly accumulated to microthrombi formed in small vessels of the organs. The scattered silver grains were widely observed on the hepatocytes. This result suggested that t-PA bound to the parenchymal cell surface might be transported into the hepatocytes by receptor-mediated endocytosis. On the other hand, when [125I]urokinase plasminogen activator [( 125I]u-PA) was administered intravenously to DIC rats, many silver grains were observed on MARGM of the proximal tubules in the kidney but not seen on MARGMs of the glomeruli in the kidney, nor in the lung, liver, and spleen. This observation suggested that u-PA might not have a characteristic to accumulate to thrombi.
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PMID:Localization of tissue plasminogen activator on experimental microthrombi in rats. Microautoradiographic observations. 190 22

The respective roles of intravascular coagulation (DIC) and fibrinolysis were assessed in severe chronic liver disease by measuring thrombin-antithrombin (TAT) complexes, tissue-type plasminogen activator antigen (tPA Ag) and fibrinogen and fibrin degradation products (FgDP and FbDP respectively) in 66 patients with liver disease caused by cirrhosis (n = 34) or chronic hepatitis (n = 32) as compared to findings in a control group (n = 30). There was a significant increase of TAT complexes (P less than 0.01), tPA Ag (P less than 0.002), FDP and FbDP (P less than 0.001) in patients as compared to controls. FbDP increase was more evident in patients with cirrhosis than in those with hepatitis (P less than 0.01). Significant correlations between these parameters with some liver function tests were also demonstrated. Thus, in patients with severe liver disease, an increased thrombin activity, as demonstrated by high TAT levels; followed by hyperfibrinolysis suggest that a low grade DIC may occur.
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PMID:Thrombin activation and increased fibrinolysis in patients with chronic liver disease. 190 1

Quantitative assay for fibrin monomer was done by use of a chromogenic substrate (S-2390, Coa set fibrin monomer). Samples from DIC prone patients with the underlying disease were assayed and classified into four groups. The pre DIC group showed higher FM values than the control with no laboratory coagulation abnormality, although the FDP . D-dimer showed no significant rise. FM assay is a useful marker for the detection of early coagulopathy in DIC. Administration of the AT III concentrate in the case of low level of plasma ATIII, thrombin . antithrombin complex I (TAT) caused a significant transient rise. The clinical course of DIC by TAT is often affected by the fluctuation of ATIII level in plasma, the usefulness of FM is that it reflects the real thrombin generation in DIC.
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PMID:[Fibrin monomer assay]. 192 Aug 60


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