Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.21.68 (tissue plasminogen activator)
 11,311 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tissue kallikrein and factor Xa were found to activate tissue plasminogen activator (t-PA) at a rate comparable with that of plasmin. During the activation reaction, the single-chain molecule was converted into a two-chain form. A slight t-PA activating activity was also found in plasma kallikrein. Other activated coagulation factors, factor XIIa, factor XIa, factor IXa, factor VIIa, thrombin and activated protein C had no effect on t-PA activation. t-PA was also activated by a tissue kallikrein-like enzyme that was isolated from the culture medium of melanoma cells. These results indicate that tissue kallikrein and factor Xa may participate in the extrinsic pathway of human fibrinolysis.
 ...
PMID:Proteolytic activation of tissue plasminogen activator by plasma and tissue enzymes. 656 16

The ECAT Angina Pectoris Study is a European multicentre study with the aim of investigating the pathogenetic and predictive role of haemostatic factors in the progression of coronary heart disease. It is the largest study performed up to now with regard to both the number of patients with angina pectoris (n = 3043) and the number of haemostasis assays (n = 23) included. The present paper presents baseline cross-sectional data with particular reference to the relationship of haemostatic factors with each other and with the coronary risk factors age, gender and acute-phase reaction (1). Two clusters of haemostatic factors could be distinguished in which each variable was correlated (P < 0.001) to every other variable: (a) Eight fibrinolysis assays including t-PA, PAI-1 and euglobulin clot lysis time (ECLT), for which PAI-1 appeared to be the dominating factor; (b) antithrombin III, protein C, alpha 2-antiplasmin and plasminogen, the interdependence of which has no obvious explanation. (2). Twelve out of the 23 haemostasis assays were associated (P < or = 0.01) with age. Except for alpha 2-antiplasmin, these relationships indicated an increased tendency to thrombosis with increasing age. (3). Gender differences found in 14 haemostasis parameters do not indicate a consistent difference in the tendency to thrombosis between men and women. Eight haemostasis parameters were on average higher in female than in male patients in the age group over 50 years. (4). C-reactive protein, an acute-phase reactant, was positively correlated (P < 0.001) with fibrinogen, factor VIIIc, von Willebrand factor, the fibrinolysis assays t-PA, PAI-1, ECLT and plasminogen.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Haemostasis factors in angina pectoris; relation to gender, age and acute-phase reaction. Results of the ECAT Angina Pectoris Study Group. 749 59

The human intracellular serine proteinase inhibitor, proteinase inhibitor 6 (PI-6), was expressed in the methylotropic yeast Pichia pastoris. The PI-6 cDNA was modified to encode six histidine residues immediately after the initiation codon, and was placed under the control of the P. pastoris alcohol oxidase promoter in the vector pHIL-D2. On the methanol induction, active recombinant PI-6 was produced within the yeast cells, and following cell lysis, was separated from yeast proteins by affinity chromatography using nickel nitrilo-tri-acetic acid (NTA) resin. The interaction of recombinant PI-6 with a range of serine proteinases was studied. Second order association rate constants (ka) were derived for the interaction with trypsin (1.8 x 10(6) M-1 s-1), thrombin (1.2 x 10(5) M-1 s-1), urokinase plasminogen activator (4.0 x 10(4) M-1 s-1), plasmin (1.3 x 10(6) M-1 s-1), and activated protein C (7.5 x 10(3) M-1 s-1). By monitoring complex formation, recombinant PI-6 was also shown to interact with factor Xa. No complex formation was observed with chymotrypsin, human leukocyte elastase, cathepsin G and tissue plasminogen activator, although PI-6 is apparently a substrate for chymotrypsin, leukocyte elastase and cathepsin G.
 ...
PMID:Production and characterization of recombinant human proteinase inhibitor 6 expressed in Pichia pastoris. 754 63

In this study the influence of low-dose oral contraceptives (OC) on the different components of the fibrinolytic system before and immediately after maximal exercise was examined in a group of 18 moderately active women. Nine women using OC and nine control women performed a maximal effort treadmill protocol. Comparison of the resting parameters revealed higher plasma FbDP, plasminogen, alpha 2-antiplasmin and protein C concentrations, and lower PAI activity in the OC group. No differences were observed in plasma concentrations of t-PA antigen, t-PA activity, PAI antigen, antithrombin III, and protein S. Acute maximal exercise resulted in significant increases in t-PA antigen, t-PA activity, t-PA/PAI complexes, and FbDP in both groups of subjects, while PAI activity was reduced. No significant differences were found for the change in those parameters between control and OC users. Exercise induced no variation in any of the groups for PAI antigen, alpha 2-antiplasmin, plasminogen, protein C, or protein S. Our data suggest that changes in the fibrinolytic system induced by physical exercise are not affected by oral contraceptives.
 ...
PMID:Effects of oral contraceptives on fibrinolytic response to exercise. 756 82

Hemostatic indices were determined in 45 healthy light breed foals, from birth to 1 month of age, and in 20 healthy adult (> 2 years of age) light breed horses. Blood samples were obtained from each foal at 4 ages: 1) < 24 hours, 2) 4-7 days, 3) 10-14 days, and 4) 25-30 days. The following hemostatic indices were determined: platelet count; prothrombin and activated partial thromboplastin times; activity concentrations of protein C, antithrombin III, plasminogen, alpha-2 antiplasmin, tissue plasminogen activator, and plasminogen activator inhibitor-1; plasma protein C antigen and fibrinogen concentrations; and serum fibrin degradation products concentration. Prothrombin and activated partial thromboplastin times were significantly longer at birth than in older foals. The plasma concentrations of the following were significantly lower at birth than in older foals: antithrombin III, plasminogen and tissue plasminogen activator activities, protein C antigen, and fibrinogen. Concentrations of the following were significantly higher at birth than in older foals: protein C and plasminogen activator inhibitor-1 activities and fibrin degradation products. These results indicate that hemostatic indices of neonatal foals differ significantly from those of older foals and adults. With the exceptions of antithrombin III and tissue plasminogen activator activities, all hemostatic indices measured in foals at 1 month of age were equivalent to adult values.
 ...
PMID:Hemostatic indices in healthy foals from birth to one month of age. 757 55

Components of the coagulation and fibrinolytic cascades, prothrombin and activated partial thromboplastin times, endotoxin activity, and albumin concentration were measured in blood and peritoneal fluid from 20 healthy horses and from 153 horses with acute gastrointestinal tract diseases at admission. Overall, 77% (117/153) of affected horses survived to discharge from the hospital, and 85% (82/97) of horses discharged were reported to be normal 9 to 14 months later. Significant differences in hemostatic factors were more common in peritoneal fluid than in blood. Tissue plasminogen activator, plasminogen, protein C, antithrombin III, and alpha 2-antiplasmin activities and concentrations of fibrinogen and fibrin degradation products were significantly (P < 0.05) greater in peritoneal fluid from horses with colic, and, with the exception of fibrinogen concentration, were associated with detection of endotoxin. Higher values for these variables, except tissue plasminogen activator activity, were significantly (P < 0.05) associated with survival. Plasminogen, antithrombin III, and alpha 2-antiplasmin activities were significantly (P < 0.05) greater in peritoneal fluid from horses with inflammatory or strangulating lesions, compared with those in horses with simple colic. Plasminogen-activator inhibitor type 1 activity, fibrin degradation products concentration, and prothrombin time were significantly (P < 0.05) greater in the blood of horses with colic. Survival was inversely associated with significantly (P < 0.05) greater intravascular concentrations of fibrin degradation products and fibrinogen and prothrombin time. This study revealed marked contrasts between peritoneal and intravascular coagulation and fibrinolysis in horses with colic, indicating that inferences regarding the peritoneal environment, particularly with respect to fibrinolytic capacity, should not be made on the basis of factors measured in blood.
 ...
PMID:Intravascular and peritoneal coagulation and fibrinolysis in horses with acute gastrointestinal tract diseases. 759 47

The authors investigated the behaviour of some markers of the haemostatic balance in a group of patients with acute focal cerebral vasculopathy. The series consists of 70 female patients (mean age: 61 +/- 5), 25 of whom suffering from TIA and 45 from thrombotic stroke; 40 normal controls (mean age 43 +/- 5) were also considered. For each patient after an overnight fasting a withdrawal of venous blood was done within 24-36 hours after the admission. For each sample the determination of seven prothrombotic markers [(fibrinogen (F), factor VII (F VII), antithrombin III (AT III), protein C (PC), protein S (PS) (coagulometric method IL), tissue plasminogen activator (t-PA), plasminogen activator inhibitor (PAI-1) (ELISA method Boehringer)] and of three prethrombotic markers [(fibrinopeptide A (FPA), beta-thromboglobulin (BTG) and D-dimer (D-D) (ELISA method, Boehringer)] was performed. The results obtained in the group of the cerebrovasculopathic patients compared to the controls showed a significant increase of F (p < 0.001), F VII (p < 0.005), BTG (p < 0.05) and D-D (p < 0.01), whereas significant differences regarding AT III, PC, PS, t-PA, PAI and FPA were not observed. The authors hypothesized that the increased levels of fibrinogen and factor VII in the cerebrovascular subjects, globally considered, may depend on a marked prothrombotic state, linked in a pathogenetic sense to the vascular disease; the existence of a prethrombotic state is also documented by the increase of betathromboglobulin and D-dimer.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Haemostatic balance in patients with acute focal cerebral vasculopathy. 760 35

Serum complement levels have been found to be predictive of myocardial infarction up to 4 years before the acute event. To assess whether they are a marker of a hypercoagulable state, the serum or plasma levels of C3, C4, C3a, C4a, C1 inactivator, antithrombin III, protein S, protein C, fibrinogen and tissue plasminogen activator were measured in 31 patients with previous myocardial infarction and 33 controls (all males, 40-60 years old). C3, C4 and fibrinogen (which share the common characteristic of being acute phase proteins) were correlated and were associated with previous myocardial infarction, although this association persisted only for C4 in multivariate analysis. None of the coagulative variables directly involved in the complement system differed significantly in the two groups.
 ...
PMID:Complement components and fibrinogen: correlations and association with previous myocardial infarction. 761 96

To assess hemostatic risk factors for sudden death in patients with stable angina, 323 consecutive patients were recruited prospectively. Patients with clinical heart failure or recent myocardial infarction were excluded. The following clinical variables were recorded: age, gender, smoking habits, hypertension, previous myocardial infarction, left ventricular hypertrophy, and severe ventricular arrhythmia. Angiographic variables included coronary extent, assessed from Jenkins' and mean atherosclerotic scores, and left ventricular ejection fraction. Lipid variables included total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and apolipoproteins A-I and B. Hemostatic factors included fibrinogen, fibrinopeptide A, antithrombin III, factor VIII antigen, factor VIII coagulant, protein C, plasminogen, alpha 2 antiplasmin, euglobulin clot lysis time, tissue plasminogen activator before and after venous occlusion, and plasminogen activator inhibitor. There were 34 deaths, 19 of which were sudden during the follow-up period (60 +/- 17 months). The association between each variable and the risk of sudden death was assessed by calculating the relative risk with the Cox univariate model. All significant predictors from the univariate analysis were then incorporated in a Cox multivariate model to select the independent predictors of sudden death. The independent predictors of sudden death were left ventricular hypertrophy (p < 0.04), lower left ventricular ejection fraction (p < 0.04), and shorter euglobulin clot lysis time after venous occlusion (p < 0.02), whereas fibrinogen (p < 0.07) and Jenkins' score (p < 0.08) were borderline. Determination of hemostatic variables, especially those pertaining to dynamic fibrinolysis, may thus be of value in assessing risk of sudden death.
 ...
PMID:Predictive value of hemostatic factors for sudden death in patients with stable angina pectoris. 761 16

The aim of this study was to investigate whether abnormalities in the fibrinolytic system and in the naturally occurring anticoagulant proteins could contribute to the thrombotic risk in essential thrombocythemia. Euglobulin lysis time, fibrin plate lysis area, tissue plasminogen activator antigen, and activity and plasminogen activator inhibitor antigen were measured before and after venous occlusion in a group of 16 patients with essential thrombocythemia and in 16 healthy age and sex matched controls. In addition, resting levels of antithrombin III, D-dimer, prothrombin fragment 1 + 2, and protein C and S were assessed. The results were related to the presence or absence of a thrombotic history. The results demonstrated that the patients had a significantly elevated fibrin plate lysis area and significantly decreased plasminogen activator antigen, both at baseline and after venous occlusion. They also had significantly decreased levels of plasma protein C and total protein S. There was a modest, non-significant elevation in the plasma concentration of D-Dimer and F 1 + 2. Those patients with a history of thrombosis had significantly lower protein C levels compared with individuals without a thrombotic history. We conclude that patients with essential thrombocythemia have evidence of activated fibrinolysis in the resting state and after stimulation. This, and the decreased levels of protein C and total protein S, may be secondary to chronic clinically occult thrombosis occurring in myeloproliferative disorders.
 ...
PMID:Low proteins C and S and activation of fibrinolysis in treated essential thrombocythemia. 763 71


<< Previous 1 2 3 4 5 6 7 8 9 10