Tissue Plasminogen Activator-plasminogen Activator Inhibitor-1 Research Articles

Alterations of Hemostatic Molecular Markers During Acute Large Vessel Occlusion Stroke.

This study aimed to investigate regional levels of TAT (thrombin-antithrombin complex), PIC (plasmin-α2 plasmin inhibitor complex), t-PAIC (tissue plasminogen activator-plasminogen activator inhibitor complex), sTM (soluble thrombomodulin), and D-dimer, along with their associations with clinical and procedural characteristics in patients with acute ischemic stroke undergoing endovascular thrombectomy. We retrospectively analyzed 166 consecutive patients with acute ischemic stroke (62±11.54 years of age, 34.3% women) using prospectively maintained clinical databases and blood samples from local ischemic (proximal to thrombus) and systemic (femoral artery, self-control) arterial compartments. Levels of TAT, PIC, t-PAIC, and D-dimer were significantly elevated, whereas sTM was significantly reduced, in local ischemic regions compared with their systemic levels. Each 1-unit increase in ischemic TAT (adjusted odds ratio [aOR], 1.086 [95% CI, 1.03-1.145]; P=0.002; area under the curve [AUC], 0.833) and PIC (aOR, 1.337 [95% CI, 1.087-1.644]; P=0.006; AUC, 0.771) correlated significantly with higher symptomatic intracranial hemorrhage risk. Additionally, each 1-unit increase in ischemic TAT (aOR, 1.076 [95% CI, 1.016-1.139]; P=0.013; AUC, 0.797), PIC (aOR, 1.554 [95% CI, 1.194-2.022]; P=0.001; AUC, 0.798), and sTM (aOR, 0.769 [95% CI, 0.615-0.961]; P=0.021; AUC, 0.756) was significantly associated with an increased risk of an unfavorable 90-day outcome (modified Rankin scale of 3-6). These hemostatic molecules, individually or combined, significantly improved the predictive power of conventional risk factors, as evidenced by significant increases in net reclassification improvement and integrated discrimination improvement (all P<0.01). We observed a hyperactive state of the coagulation-fibrinolysis system within the local ischemic region during hyperacute stroke. Rapid automated measurement of hemostatic molecular markers, particularly TAT, PIC, and sTM, during intra-arterial procedures may provide additional information for stroke risk stratification and therapeutic decision-making, and warrants further investigation.

Early identification of lung cancer patients with venous thromboembolism: development and validation of a risk prediction model

IntroductionVenous thromboembolism(VTE) is a leading cause of death in patients with lung cancer. Furthermore, hospitalization of patients with advanced lung cancer for VTE treatment represents a major economic burden on the national public health resources. Therefore, we performed this prospective study to identify clinical biomarkers for the early identification of VTE in lung cancer patients.MethodsThis prospective study enrolled 158 patients with confirmed lung cancer, including 27 who were diagnosed with VTE within six months of the follow-up after lung cancer diagnosis. Multivariate logistic regression analysis was used to evaluate the diagnostic performancese of all the relevant clinical features and laboratory indicators in identifying lung cancer patients with a higher risk of VTE. A novel risk prediction model was constructed consisting of five clinical variables with the best diagnostic performances and was validated using the receiver operation characteristic(ROC) curves. The diagnostic performances of the new risk prediction model was also compared with the Khorana risk score (KRS) and the Padua risk score (PRS).ResultsThe VTE group of lung cancer patients (n = 27) showed significantly higher serum levels of fibrin degradation products (FDP), D-dimer, thrombomodulin (TM), thrombin-antithrombin-complex (TAT), α2-plasmin inhibitor-plasmin Complex (PIC), and tissue plasminogen activator-plasminogen activator inhibitor complex (t-PAIC) compared to those in the non-VTE group (n = 131). ROC curve analyses showed that the diagnostic efficacy of the new VTE risk prediction model with TM ≥ 9.75 TU/ml, TAT ≥ 2.25ng/ml, t-PAIC ≥ 7.35ng/ml, history of VTE, and ECOG PS score ≥ 2 was superior than the KRS and the PRS in the early identification of lung cancer patients with a higher risk of VTE.ConclusionsThe new risk prediction model showed significantly high diagnostic efficacy in the early identification of lung cancer patients with a high risk of VTE. The diagnostic efficacy of the new risk prediction model was higher than the KRS and the PRS in this cohort of lung cancer patients.

Clinical study on the feasibility of new thrombus markers in predicting massive cerebral infarction.

This study investigated the diagnostic performance of the thrombin-antithrombin complex (TAT), plasmin-α2 plasmin inhibitor complex (PIC), tissue plasminogen activator-plasminogen activator inhibitor complex (t-PAIC), and thrombomodulin (TM) in the early identification of massive cerebral infarction. A total of 423 patients with cerebral infarction confirmed by imaging examination were divided into the massive cerebral infarction (MCI) group and the non-massive cerebral infarction (NMCI) group. TAT, PIC, t-PAIC, and TM were measured immediately after admission. The diagnostic performance was analyzed by the receiver characteristic operating curve (ROC). The median plasma concentrations of TAT, PIC, and t-PAIC in patients with MCI at early onset were 5.10 ng/ml, 1.11 μg/ml, and 8.80 ng/ml, respectively, which were higher than those in patients with NMCI (2.20 ng/ml, 0.59 μg/ml, and 7.35 ng/ml), and the difference was statistically significant (P < 0.001). TAT was shown to be an independent risk factor for the development of massive cerebral infarction by a multivariate logistic regression analysis (OR = 1.138). A ROC curve analysis showed that PIC had the best performance in identifying MCI at an early stage (AUC = 82.8%), with a sensitivity of 80.7% and a specificity of 76.2% when the PIC concentration was ≥0.8 μg/ml; TAT had the highest specificity in identifying MCI, with a specificity of 80.6% when the TAT concentration was ≥3.97 ng/ml. The detection of PIC, TAT, t-PAIC, and TM is a comprehensive assessment of vascular endothelial damage and activation of the coagulation and fibrinolytic systems and has diagnostic value for early identification of patients with MCI, which, together with its ease of detection, can be used as a plasma marker for early identification of large vessel occlusion.

A Pharmacokinetic and Pharmacodynamic Investigation of an ε-Aminocaproic Acid Regimen Designed for Cardiac Surgery With Cardiopulmonary Bypass

To investigate the pharmacokinetics and pharmacodynamics of an ε-aminocaproic acid (EACA) regimen designed for cardiac surgery with cardiopulmonary bypass (CPB). Prospective observational study requiring blood sampling to measure EACA concentrations and fibrinolysis markers (fibrinogen, D-dimer, α2-antiplasmin, and tissue plasminogen activator-plasminogen activator inhibitor [tPA-PAI-1] complex). Single-center, tertiary medical center. Patients who underwent cardiac surgery with CPB between 2018 and 2019 for aortic or mitral valve replacement/repair or coronary artery bypass grafting. Previous sternotomy patients were included. None. The pharmacokinetics of EACA, during CPB, were described by a 3-compartment disposition model. EACA concentrations were greater than 130 mg/L in all patients after CPB and in most patients during CPB. The D-dimer level trended up and reached a peak median level of 1.35 mg/L of fibrinogen equivalence units (FEU) at 15 minutes after protamine administration. The median change in D-dimer (ΔD-dimer) from baseline to 15 minutes after protamine was 0.34 (-0.48 to 3.81) mg/L FEU. ΔD-dimer did not correlate with EACA concentration intraoperatively, urine output, body weight, glomerular filtration rate, cell salvage volume, and ultrafiltration volume. The median 24-hour chest tube output was 445 (180-1,011) mL. This regimen provided maximum EACA concentrations near the time of protamine administration, with a total perioperative dose of 15 g. Most patients had EACA concentrations greater than the target during CPB. ΔD-dimer did not correlate with EACA concentration. The median 24-hour chest tube output compared well to similar studies that used higher doses of EACA.

The study on the association between tissue plasminogen activator-plasminogen activator inhibitor-1 complex and risk of coronary disease

Objective The aim of this study was to discuss the effect and clinical value of plasma Tissue Plasminogen Activator-Plasminogen Activator Inhibitor-1 Complex (t-PAIC) in the coronary heart disease (CAD). Methods This is a retrospective study. From January 2017 to March 2018, 203 patients with CAD were recruited from Renmin Hospital of Wuhan University. 130 cases were selected for control group at the same period. Plasma concentrations of t-PAIC, blood RBC, Hb, WBC and other routine biochemical markers were quantified. Results The plasma t-PAIC level in CAD group 12.75(9.0-17.93) ng/ml was significantly higher than that in healthy control group 7.70(6.10-9.41) ng/ml (Z=9.208, P<0.001). Logistic regression analysis showed that the TG, LPa, t-PAIC were independent risk factors for CAD[OR(95%CI)], [1.762(1.076-2.884); 1.002(1.000-1.003); 1.338 (1.171-1.529)]. The t-PAIC level was positively correlated with the severity of CAD. Compared with control group, the level of t-PAIC was higher in mild group(11.64±0.59)ng/ml and severe group(15.84±0.72)ng/ml, and the plasma t-PAIC level was positively correlated with Gensini score(r=0.471, P<0.001). Multiple linear regression analysis showed that there was a positive correlation among the plasma t-PAIC and LDL-C, Glu, WBC (β coefficient=0.673, 0.305, 0.263, P=0.037, 0.002, 0.006). In addition, there was abnormal increase of plasma t-PAIC in CAD patients with poor prognosis (H=82.210, P<0.001). Conclusion Plasma t-PAIC is an independent risk factor of CAD. The significantly increase of plasma t-PAIC might be an important predictor of incidence of CAD and unfavourable prognosis. (Chin J Lab Med, 2018, 41: 420-424) Key words: Coronary disease; Tissue plasminogen activator; Plasminogen activator inhibitor 1; Risk factors

Impaired plasminogen binding in patients with venous thromboembolism: Association with protein carbonylation

IntroductionVenous thromboembolism (VTE) is associated with hypofibrinolysis. Its mechanisms are poorly understood. We investigated plasminogen-fibrin interaction and its association with fibrinolytic capacity and protein oxidation/carbonylation in VTE patients. Materials and methodsPlasma-purified plasminogen conversion to plasmin and surface plasmon resonance employed for plasminogen-fibrin interactions were individually evaluated in all healthy controls and non-anticoagulated patients following VTE, 10–23months since the event. We also assessed plasma fibrin clot permeability (Ks), clot lysis time (LT), activators and inhibitors of fibrinolysis together with oxidation/carbonylation markers. ResultsVTE patients had impaired plasminogen binding to fibrin (apparent Kd, +290%, p=0.002), reduced rate of plasmin generation (−4.7%, p=0.001), and longer LT (+18.6%, p<0.001) compared with controls. Fibrinogen and Ks were similar in both groups. Apparent Kd correlated with LT (r=0.43, p=0.037), tissue plasminogen activator-plasminogen activator inhibitor 1 (tPA-PAI-1) complexes (r=0.63, p=0.012), and active PAI-1 (r=0.49, p=0.03). Compared with controls, VTE patients had higher thiobarbituric acid reactive substances (TBARS), total protein carbonyl content (PC), and lower total antioxidant capacity (all p<0.001), that all were associated with LT (r=0.61, r=0.56, and r=−0.47, respectively, all p<0.05). Impaired plasminogen binding to fibrin reflected by apparent Kd positively correlated with TBARS (r=0.48, p=0.032) and PC (r=0.54, p=0.013) in the whole group. ConclusionsPlasminogen-fibrin interactions are altered in young and middle-aged VTE patients, without known thrombophilias, except increased factor VIII. The mechanisms underlying these phenomena remain to be established.

Coagulofibrinolytic changes in patients with disseminated intravascular coagulation associated with post-cardiac arrest syndrome― Fibrinolytic shutdown and insufficient activation of fibrinolysis lead to organ dysfunction

IntroductionPost-cardiac arrest syndrome (PCAS) is often associated with disseminated intravascular coagulation (DIC), thus leading to the development of multiple organ dysfunction syndrome (MODS). The aim of this study was to examine the pathophysiological relationships between coagulation, fibrinolysis and fibrinolytic shutdown by evaluating the levels of coagulofibrinolytic markers, including soluble fibrin, thrombin-activatable fibrinolysis inhibitor (TAFI), tissue plasminogen activator-plasminogen activator inhibitor-1 complex (tPAIC), plasmin-alpha2 plasmin inhibitor complex (PPIC), neutrophil elastase and fibrin degradation product by neutrophil elastase (EXDP). Materials and MethodsFifty-two resuscitated patients were divided into two groups: 22 DIC and 30 non-DIC patients. ResultsThe levels of soluble fibrin, PPIC, tPAIC, EXDP and neutrophil elastase in the DIC patients with PCAS were significantly higher than those observed in the non-DIC patients. The values of the tPAIC and JAAM DIC scores were found to be independent predictors of increased SOFA scores in the DIC patients. The MODS patients demonstrated significantly higher levels of soluble fibrin and tPAIC; however, the levels of TAFI and EXDP were identical between the patients with and without MODS. In addition, positive correlations were observed between the levels of tPAIC and EXDP in the patients with non-MODS; however, no correlations were observed between these markers in the MODS patients. ConclusionsThrombin activation and fibrinolytic shutdown play important roles in the development of organ dysfunction in PCAS patients. Neutrophil elastase-mediated fibrinolysis cannot overcome the fibrinolytic shutdown that occurs in DIC patients with PCAS, thus resulting in the development of MODS.

A low TAFI activity and insufficient activation of fibrinolysis by both plasmin and neutrophil elastase promote organ dysfunction in disseminated intravascular coagulation associated with sepsis

IntroductionWe hypothesized that thrombin activatable fibrinolysis inhibitor (TAFI) and the activation of fibrinolysis by both plasmin and neutrophil elastase is insufficient to overcome fibrinolytic shutdown, contributing to multiple organ dysfunction syndrome (MODS) in sepsis-induced disseminated intravascular coagulation (DIC). Materials and MethodsFifty patients with sepsis were prospectively enrolled. The DIC was diagnosed based on the Japanese Association for Acute Medicine (JAAM) DIC and the International Society on Thrombosis and Haemostasis (ISTH) overt DIC criteria. ResultsThe JAAM DIC scores were independent predictors of patient death and MODS. The JAAM DIC patients, especially those who met the ISTH overt DIC criteria, showed lower TAFI activity, and higher levels of soluble fibrin, neutrophil elastase, fibrin degradation product by neutrophil elastase (EXDP), plasmin-alpha2 plasmin inhibitor complex (PPIC), tissue plasminogen activator-plasminogen activator inhibitor-1 complex (tPAIC) and D-dimer in comparison with non-DIC patients. There were differences in the levels of soluble fibrin, tPAIC, TAFI activity, and neutrophil elastase between the patients with and without MODS. However, no differences were observed in the levels of PPIC, D-dimer, or EXDP. Soluble fibrin negatively correlated with the TAFI activity. High neutrophil elastase, low TAFI activity and PPIC are independent predictors of patient death and MODS. tPAIC is an independent predictor of elevation of EXDP in DIC patients. ConclusionsActivation of fibrinolysis both by plasmin and neutrophil elastase cannot overcome fibrinolytic shutdown, leading to MODS and a poor outcome in sepsis-induced DIC. The systemic activation of neutrophils and a low TAFI activity are also involved in the pathogenesis of MODS.

THE EFFECT OF ANTITHROMBIN ON PULMONARY ENDOTHELIAL DAMAGE INDUCED BY CRUSH INJURY

After crush injury, patients often experience multiple organ dysfunction syndrome. In this study, we focused on vascular endothelial damage, which is believed to be a possible cause of multiple organ dysfunction syndrome, and revealed a pathological condition of distant organ failure. In particular, the lung is an especially prone target organ at the time of systemic inflammatory invasion after crush injury. We ascertained the effect of antithrombin (AT), which has recently attracted attention for its endothelial protective effects. Using a rat model of crush syndrome, we assessed severity of systemic inflammation and vascular endothelial damage through a blood test and degree of lung injury and centrally focused on morphological analysis of endothelium over time. Crush injury significantly elevated the blood concentration of tissue plasminogen activator-plasminogen activator inhibitor 1 complex, monocyte chemoattractant protein 1, and IL-6. Accumulation of active inflammatory cells (OX-42-positive cells) and expression of von Willebrand factor and vascular cell adhesion molecule 1 significantly increased in the lung 24 h after releasing crush. After 48 h, disarray of alveolar structure and alveolar hemorrhage appeared. Antithrombin administration significantly suppressed accumulation of inflammatory cells, expression of von Willebrand factor and vascular cell adhesion molecule 1, and mortality rate. Our research demonstrates that crush injury induces acute lung injury as distant organ failure, and it would seem that AT administration diminishes vascular endothelial damage and is effective against crush injury.

Hemostatic Abnormalities and Changes Following Bone Marrow Transplantation

Hemostatic parameters were examined in 39 patients who underwent allogeneic bone marrow transplantation (BMT). Twenty-six patients survived and 13 patients died within 6 months after BMT. The main causes of death were acute graft-versus-host disease (GVHD: n=6), veno-occlusive disease (VOD: n=2), and thrombotic microangiopathy (TMA: n=2). Plasma levels of D-dimer and thrombomodulin (TM) were significantly elevated in the non-survivor group. Plasma levels of soluble fibrin (SF) and Fas were significantly elevated in the non-survivor group at 1 to 4 weeks after BMT. Plasma levels of thrombin-antithrombin complex (TAT), D-dimer, and tissue plasminogen activator-plasminogen activator inhibitor-1 complex (tPA-PAI-1 complex) were significantly elevated in patients with complications after BMT. Plasma levels of TAT, D-dimer, and tPA-PAI-1 complex were significantly elevated in patients with GVHD. These results suggest that abnormalities of hemostatic parameters might predict poor outcomes or complications in patients with BMT.

Hemostatic Abnormalities Following Bone Marrow Transplantation

Hemostatic abnormalities in 26 patients following bone marrow transplantation (BMT) were examined. In the event-free survival group, the plasma levels of antithrombin (AT) and protein C (PC) were significantly decreased 1 and 2 weeks after BMT, and the plasma levels of thrombomodulin (TM) and tissue plasminogen activator-plasminogen activator inhibitor-1 complex (tPA-PAI-I complex) were significantly increased from 4 weeks to 13 weeks after BMT. Excepting AT, there was no significant difference in hemostatic parameters before BMT among the event-free survival, 6-month survival, and death within 6 months groups. On day 0 following BMT, only plasma AT levels were significantly lower in the 6-month survival group than in the death within 6 months group. From 1 to 3 weeks after BMT, plasma levels of AT or PC were significantly lower in the death within 6 months group than in the 6-month survival group. From 1 to 5 weeks after BMT, the plasma levels of TM and tissue type plasminogen activator-plasminogen activator inhibitor-I complex (tPA-PAI-I complex) were significantly higher in the 6-month survival group than in the death within 6 months group. From 1 to 13 weeks after BMT, the plasma levels of D-dimer or soluble fibrin monomer (SFM) were significantly higher in the death within 6 months group than in the 6-month survival group. There was no remarkable difference in plasma levels of thrombin-antithrombin comlex or plasmin-plasmin inhibitor complex following BMT between these groups of patients. These findings suggest that the decrease in the plasma AT or PC level reflects early occurrence of complications of prognostic significance and that the increase in vascular endothelial cell markers such as plasma levels of TM or tPA-PAI-I complex reflects occurrence of complications during the middle course of BMT. Plasma levels of D-dimer and SFM may be useful markers for predicting complications associated with poor prognosis after BMT.

Elevated plasma procoagulant and fibrinolytic markers in patients with chronic obstructive pulmonary disease.

There is clinical and pathological evidence of thrombosis in pulmonary vessels of patients with chronic obstructive pulmonary disease (COPD). The purpose of this study was to investigate the presence of hypercoagulability and determine the extent of this abnormality in COPD patients. We measured plasma levels of thrombin antithrombin III complex (TAT), fibrinopeptide A (FPA), tissue plasminogen activator-plasminogen activator inhibitor (tPA-PAI): markers of coagulation-fibrinolysis-system, and also beta-thromboglobulin (beta-TG): a marker of platelet activation, in 40 COPD patients and in 20 control subjects. Measurements were also repeated 12 months after entry in all patients. TAT, FPA, tPA-PAI, and beta-TG concentrations were significantly higher in COPD than in control subjects. At 12 months follow-up, deltaA-aDO2 and delta%FEV1 were significantly higher in patients with high TAT or tPA-PAI levels than in patients with low levels and TAT, FPA and tPA-PAI levels remained elevated, although beta-TG levels decreased after domiciliary O2 therapy. Our results showed an enhanced prothrombotic process in COPD patients, which could potentially account for the increased thrombosis in pulmonary vessels in these patients.

Close relationship of tissue plasminogen activator-plasminogen activator inhibitor-1 complex with multiple organ dysfunction syndrome investigated by means of the artificial pancreas.

Glucose tolerance (GT) has not been taken into consideration in investigations concerning relationships between coagulopathy and multiple organ dysfunction syndrome (MODS), and endothelial cell activation/endothelial cell injury (ECA/ECI) in septic patients, although coagulopathy is known to be influenced by blood glucose level. We investigated those relationships under strict blood glucose control and evaluation of GT with the glucose clamp method by means of the artificial pancreas in nine septic patients with glucose intolerance. The relationships between GT and blood stress related hormone levels (SRH) were also investigated. The amount of metabolized glucose (M value), as the parameter of GT, was measured by the euglycemic hyperinsulinemic glucose clamp method, in which the blood glucose level was clamped at 80 mg/dl under a continuous insulin infusion rate of 1.12 mU/kg per min, using the artificial pancreas, STG-22. Multiple organ failure (MOF) score was calculated using the MOF criteria of Japanese Association for Critical Care Medicine. Regarding coagulopathy, the following parameters were used: disseminated intravascular coagulation (DIC) score (calculated from the DIC criteria of the Ministry of Health and Welfare of Japan) and the parameters used for calculating DIC score, protein-C, protein-S, plasminogen, antithrombin III (AT-III), plasminogen activator inhibitor-1 (PAI-1), and tissue plasminogen activator-PAI-1 (tPA-PAI-1) complex. Thrombomodulin (TM) was measured as the indicator of ECI. There were no significant correlations between M value and SRH, parameters indicating coagulopathy and the MOF score. The MOF score and blood TM levels were positively correlated with DIC score, thrombin-AT-III complex and tPA-PAI-1 complex, and negatively correlated with blood platelet count. GT was not significantly related to SRH, coagulopathy and MODS under strict blood glucose control. Hypercoagulability was closely related to MODS and ECI. Among the parameters indicating coagulopathy, tPA-PAI-1 complex, which is considered to originate from ECA, seemed to be a sensitive parameter of MODS and ECI, and might be a predictive marker of MODS. The treatment for reducing hypercoagulability and ECA/ECI were thought to be justified as one of the therapies for acutely ill septic patients.

Do Tissue Plasminogen Activator-Plasminogen Activator Inhibitor-1 Complexes Relate to the Complications of Insulin-Dependent Diabetes Mellitus? Pittsburgh Epidemiology of Diabetes Complications Study

The purpose of this study was to examine the potential relationship of tissue plasminogen activator-plasminogen activator inhibitor-1 (tPA-PAI-1) complexes and diabetic complications in individuals with insulin-dependent diabetes mellitus (IDDM). To address this issue, data from the third follow-up visit of participants in the Epidemiology of Diabetes Complications (EDC) study were examined. There were 454 participants, aged 32 ± 8 years, with duration of IDDM of 23 ± 8 years. Higher levels of tPA-PAI-1 complexes were seen for both men and women with IDDM complications. Specifically, statistically significant differences were seen in men with neuropathy (1.81 ± 0.9 versus 1.42 ± 0.8 ng/mL, p < 0.01), microalbuminuria (1.77 ± 1.1 versus 1.35 ± 0.6 ng/mL, p < 0.01), retinopathy (1.67 ± 0.9 versus 1.43 ± 0.8 ng/mL, p < 0.05), and lower extremity arterial disease (1.93 ± 0.7 versus 1.50 ± 0.9 ng/mL, p < 0.05) versus men without the particular complication. In women, higher complex levels were shown for those with retinopathy (1.51 ± 0.8 versus 1.29 ± 1.1 ng/mL, p < 0.01). Potential mechanisms for the relationship of higher complex levels and diabetic complications include an altered fibrinolytic response and/or insulin resistance. Because the results are cross sectional, it cannot be established whether the higher concentration of complexes is a result of the presence of complications or are antecedent. Prospective follow-up will be required to determine if tPA-PAI-1 complexes are predictive of the development of IDDM complications.

25. Coagulation factor XI: rather a fibrinolytic inhibitor than a coagulation factor

Post-cardiac arrest syndrome (PCAS) is often associated with disseminated intravascular coagulation (DIC), thus leading to the development of multiple organ dysfunction syndrome (MODS). The aim of this study was to examine the pathophysiological relationships between coagulation, fibrinolysis and fibrinolytic shutdown by evaluating the levels of coagulofibrinolytic markers, including soluble fibrin, thrombin-activatable fibrinolysis inhibitor (TAFI), tissue plasminogen activator-plasminogen activator inhibitor-1 complex (tPAIC), plasmin-alpha2 plasmin inhibitor complex (PPIC), neutrophil elastase and fibrin degradation product by neutrophil elastase (EXDP).Fifty-two resuscitated patients were divided into two groups: 22 DIC and 30 non-DIC patients.The levels of soluble fibrin, PPIC, tPAIC, EXDP and neutrophil elastase in the DIC patients with PCAS were significantly higher than those observed in the non-DIC patients. The values of the tPAIC and JAAM DIC scores were found to be independent predictors of increased SOFA scores in the DIC patients. The MODS patients demonstrated significantly higher levels of soluble fibrin and tPAIC; however, the levels of TAFI and EXDP were identical between the patients with and without MODS. In addition, positive correlations were observed between the levels of tPAIC and EXDP in the patients with non-MODS; however, no correlations were observed between these markers in the MODS patients.Thrombin activation and fibrinolytic shutdown play important roles in the development of organ dysfunction in PCAS patients. Neutrophil elastase-mediated fibrinolysis cannot overcome the fibrinolytic shutdown that occurs in DIC patients with PCAS, thus resulting in the development of MODS.

High factor-VII activity in the elderly is related to vascular disease through activation of the coagulation system.

High factor-VII activity has recently been recognized as an independent risk factor for coronary artery disease. The aim of the present study was to determine whether high levels of factor-VII activity in elderly patients are caused by endothelial cell injury and are related to vascular disease through activation of the coagulation system. We studies 27 asymptomatic healthy elderly men with high factor-VII activity (155-206%) and 22 healthy elderly men with low factor-VII activity (96-122%) selected from 246 men over 60 years of age attending annual health examinations. We also studied 36 patients with vascular disease (22 with coronary artery disease and 14 with chronic cerebral infarction). The levels of endothelium-derived markers (thrombomodulin, tissue plasminogen activator-plasminogen activator inhibitor-1 complex, active plasminogen activator inhibitor 1 and tissue factor pathway inhibitor) did not differ between the subjects with high and those with low factor-VII activity. We therefore conclude that high factor-VII activity is not primarily caused by endothelial cell injury. The high-factor-VII group had higher levels of coagulation inhibitors (protein C, antithrombin III and heparin cofactor II), coagulation activation markers (prothrombin fragment 1 + 2, D-dimer and plasmin-alpha2- plasmin-inhibitor complex), lipoprotein (a) and total cholesterol than the low-factor-VII group. The coagulation and lipid profiles of the group with vascular disease were closer to those of the high-factor-VII group than to those of the low-factor-VII group; the same was true of elevated active plasminogen activator inhibitor-1 levels. High factor-VII activity in the elderly is accompanied by hyperlipidaemia, including increased levels of lipoprotein (a), and leads to coagulation activation in vivo. Thus, elderly people with high factor-VII activity are predisposed to vascular disease.

Cross-competition for binding of alpha 1-antitrypsin (alpha 1 AT)-elastase complexes to the serpin-enzyme complex receptor by other serpin-enzyme complexes and by proteolytically modified alpha 1 AT.

The serpin-enzyme complex (SEC) receptor recognizes a pentapeptide neo-domain of alpha 1-antitrypsin (alpha 1 AT)-elastase complexes and, in so doing, mediates internalization and intracellular catabolism of the macromolecular complex, mediates an increase in synthesis of alpha 1 AT, and elicits neutrophil chemotactic activity. In previous studies we have shown that this pentapeptide domain is highly conserved among members of the serpin family and that binding of a synthetic peptide corresponding to this region (125I-peptide 105Y, SIP-PEVKFNKPFVYLI, based on alpha 1 AT sequence 359-374) to HepG2 cells is blocked by several serpin-enzyme complexes. To determine whether the SEC receptor is the primary HepG2 cell surface binding site for these serpin-enzyme complexes, we examined the capacity for serpin-enzyme complexes to compete with each other for binding to the SEC receptor. The results indicate that binding of 125I-elastase-alpha 1 AT complexes is blocked by thrombin-antithrombin III (ATIII), thrombin-heparin cofactor II, and cathepsin G-alpha 1-antichymotrypsin (alpha 1 ACT) complexes. Moreover, unlabeled elastase-alpha 1 AT complexes compete for binding of 125I-thrombin-ATIII, 125I-thrombin-heparin cofactor II, and 125I-cathepsin G-alpha 1 ACT complexes. Preformed soluble tissue plasminogen activator-plasminogen activator inhibitor 1 complexes also compete for binding of elastase-alpha 1 AT complexes to the SEC receptor but do so to a less effective extent, probably because of a less favorable pentapeptide sequence for binding to the SEC receptor. Under conditions in which these serpin-enzyme complexes would be expected to bind to the SEC receptor there is an increase in synthesis of alpha 1 AT but not in synthesis of ATIII or alpha 1 ACT. Proteolytically modified alpha 1 AT also competes for binding of 125I-elastase-alpha 1 AT complexes to the SEC receptor and vice versa. The purified 51-kDa amino-terminal fragment of alpha 1 AT does not compete for binding of 125I-elastase-alpha 1 AT complexes, indicating that the pentapeptide neodomain in the 4-kDa carboxyl-terminal fragment is sufficient for binding to the SEC receptor.

Changes in the fibrinolytic system associated with physical conditioning.

The effects of physical conditioning on plasma fibrinolytic activity were studied in two groups of subjects. Volunteers not engaged in any sport were compared with individuals having been subjected to aerobic conditioning (middle-distance runners, defined as men running more than 80 km per week). Plasma concentrations of the different components of the fibrinolytic system were evaluated before and immediately after a maximal effort treadmill protocol. Comparison of the resting parameters revealed that under basal conditions for plasma concentrations of plasminogen, fibrinogen, alpha 2-antiplasmin, protein C and protein S there were no differences between the two groups. Concentrations of the fibrin degradation products (FbDP) and fibrinogen degradation products (FgDP) were significantly higher in the runners than in the control group, indicating an increased fibrinolytic potential that seemed to be a consequence of the reduced formation of tissue plasminogen activator-plasminogen activator inhibitor (t-PA-PAI) complexes. Acute maximal exercise resulted in pronounced fibrinolysis, evidenced by the elevation of FbDP and FgDP concentrations, in both groups of subjects. The acceleration of the fibrinolytic activity was larger in conditioned individuals, which could be accounted for by a higher t-PA release and reduced formation of t-PA-PAI complexes when compared to the untrained subjects.

The activation of plasminogen by t-PA-PAI-1 complex in the absence of fibrin

The activity of tissue plasminogen activator-plasminogen activator inhibitor-1 (t-PA-PAI-1) complex to convert plasminogen to plasmin was examined by using fibrin autography and casein zymography where plasminogen was added or removed for casein layer. Fibrin autography was more sensitive to the activity of t-PA even in the complex with PAI-1, but casein zymography was more sensitive to plasmin. The inhibitory activity of PAI-1 towards t-PA diminished when plasma was clotted, thus in the presence of fibrin. These results indicate that t-PA-PAI-1 complex has a catalytic activity even in the absence of fibrin, but the activity is enhanced in its presence.

Disturbances in the tissue plasminogen activator/plasminogen activator inhibitor (TPA/PAI) system in systemic lupus erythematosus

Increased thrombogenesis observed in systemic lupus erythematosus (SLE) is derived from multiple mechanisms, including: Enhanced coagulation factor VIII:VWf activity, lupus anticoagulants, anti-phospholipid antibodies, acquired deficiencies of natural anti-thrombotic mechanisms (protein C, protein S, anti-thrombin III), and impaired fibrinolytic mechanisms. We studied the fibrinolytic mechanisms of 18 patients with systemic lupus erythematosus, selected carefully to avoid other possible causes of abnormalities in the fibrinolytic activity. Despite the fact that the euglobulin lysis time in steady state was normal in all instances, disturbances in the tissue plasminogen activator/plasminogen activator inhibitor (TPA/PAI) system were found in all SLE patients: TPA activity was undetectable in all cases, whereas it was above 0.4 IU/ml in a control group. In 72 percent of patients, the undetectable TPA activity was correlated with abnormally high PAI activity; PAI levels were normal in all members of the control group, their mean value being 0.74 versus 8.63 IU/ml for SLE patients (P less than .01). Coagulation protein C deficiency was found in 3 patients (17%). Even though within normal range, fibrinogen levels were significantly higher in SLE than in normal controls (219 versus 192 mg/dl, P less than .01) and plasminogen levels were significantly higher in SLE than in controls (117 versus 78.2%, P less than .01). Cross-linked fibrin derivatives (D-D dimers) were negative in all patients with SLE. Sixty-eight percent of SLE patients had high levels of antiphospholipid antibodies, but no correlation with the disturbances of the TPA/PAI system was found. It is concluded that most patients with SLE display severe abnormalities in the TPA/PAI anti-thrombotic system and that these abnormalities may be related to the lupus thrombophilia, apparently multifactorial in its origin.