OBJECTIVE

To evaluate the nature of accelerated fibrinolysis in hepatosplenic schistosomiasis.

METHODS

The biological activity of plasminogen (Plg), plasminogen activators (PA), alpha <em>2</em>-antiplasmin (alpha <em>2</em>-AP) and plasminogen activator inhibitor-<em>1</em> (PAI-<em>1</em>) was determined by photometric analysis in <em>1</em>5 compensated and 35 decompensated patients with endemic Egyptian hepatosplenomegaly. Quantitative measurement of plasma concentrations of tissue t-PA, t-PA-PAI-<em>1</em> complex, alpha <em>2</em>-antiplasmin-plasmin complex (alpha <em>2</em>-APP), fibrinogen degradation products (FbDP), D-dimers (D-D), thrombin-antithrombin complex (TAT) and <em>prothrombin</em> <em>fragment</em> (F <em>1</em> + <em>2</em>) complexes, using double antibody sandwich enzyme linked immunosorbent assays and grading of the degree of hepatic insufficiency according to the Child-Pugh classification, were also carried out.

RESULTS

The progressive deterioration of liver function in schistosomal patients, which matched the severity of the disease, led to simultaneous defects in profibrinolytic (decreased Plg and increased PA and t-PA) and antifibrinolytic (decreased alpha <em>2</em>-AP and PAI-<em>1</em>) factors-the latter defects being the most prominent-resulting in significant generation of plasmin (increased APP complexes) and therefore enhanced fibrinolysis (increased FbDP and D-dimer). The raised concentrations of FbDP, D-D, TAT and F <em>1</em> + <em>2</em> established its secondary nature.

CONCLUSIONS

These findings suggest that the amount of PAI-<em>1</em> available to bind and neutralise circulating t-PA may be a critical factor in the progress of hyperfibrinolysis observed in hepatosplenic schistosomiasis, and that the pronounced reduction in its plasma concentration may be regarded as a potential warning indicator of haemostatic imbalance in decompensated schistosomal patients at high risk of variceal bleeding.

Heparin-induced thrombocytopenia (HIT) is mediated by antibodies directed against the heparin/platelet factor 4 (PF4) complex. Our aim was to investigate whether the antibody titre is associated with the degree of in vivo thrombin generation. We measured the anti-heparin/PF4-antibody titre, <em>prothrombin</em> <em>fragments</em> F<em>1</em>+<em>2</em>, thrombin-antithrombin (TAT) complexes and D-dimers in plasma samples from <em>2</em><em>2</em>5 patients with suspected HIT. Antibody titres as detected by a particle gel immunoassay strongly correlated with optical density values measured by ELISA (r=0.84, p<0.000<em>1</em>). Patients with titres>> or =4 (n=44) had significantly higher median levels of F<em>1</em>+<em>2</em> (<em>2</em>.49 nmol/l), TAT (<em>1</em>3.0<em>1</em> microg/l) and D-dimers (3340 microg/l) compared to patients with undetectable antibodies (n=<em>1</em>48; F<em>1</em>+<em>2</em> <em>1</em>.6<em>1</em> nmol/l, TAT 4.95 micro g/l, D-dimers <em>1</em>9<em>1</em><em>1</em> micro g/l; p<0.000<em>1</em> for all comparisons) or patients with titres of <em>1</em>-<em>2</em> (n=33; F<em>1</em>+<em>2</em> <em>1</em>.44 nmol/l, p=0.00<em>1</em>4; TAT 4.37 microg/l, p=0.00<em>1</em>8; D-dimers <em>2</em><em>2</em>3<em>1</em> microg/l, p=0.00<em>1</em>6). Multivariate analysis indicated the anti-heparin/PF4-antibody titre as an independent predictor for F<em>1</em>+<em>2</em> (p=0.0036), TAT (p=0.0<em>1</em>76) and D-dimer (p=0.0003) levels. This relationship remained statistically significant after exclusion of patients with concomitant prothrombotic conditions and/or thromboembolic complications during heparin treatment. These data demonstrate that high anti-heparin/PF4-antibody titres are independently associated with an increased in vivo thrombin generation. Rapid determination of the anti-heparin/PF4-antibody titre could help guide clinical management, identifying a subset of HIT-patients who are at high risk of developing thromboembolic complications and possibly require alternative anticoagulation in therapeutic dosage even in the context of isolated HIT.

Intravenous heparin, a fundamental therapy in the treatment of patients with acute coronary syndromes, acts by inhibiting thrombin and activated factors X, IX, XI, and XII. It has also been demonstrated that heparin reduces plasma fibrinopeptide A, a marker of thrombin activity, but it is unknown whether it decreases <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em>, an indirect marker of thrombin generation. We measured the plasma levels of <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em>, fibrinopeptide A, and antithrombin III in 64 consecutive patients with unstable angina or myocardial infarction receiving intravenous heparin. Blood samples were obtained at baseline (before any treatment) and then at 90 minutes and <em>2</em>4 and 48 hours after the administration of an intravenous bolus of heparin (5000 IU) followed by a continuous infusion of <em>1</em>000 IU per hour to maintain activated partial thromboplastin time at more than double its baseline levels. In comparison with baseline, there was a significant decrease in fibrinopeptide A at 90 minutes and at <em>2</em>4 and 48 hours (baseline, <em>2</em>.3 nmol/L; 90 minutes, <em>1</em>.<em>1</em>5 nmol/L; <em>2</em>4 hours, <em>1</em>.4 nmol/L; 48 hours, <em>1</em>.<em>2</em> nmol/L; P < .000<em>1</em>) but no change in <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> levels (baseline, <em>1</em>.<em>2</em>7 nmol/L; 90 minutes, <em>1</em>.3 nmol/L; <em>2</em>4 hours, <em>1</em>.33 nmol/L; 48 hours, <em>1</em>.<em>2</em>9 nmol/L; P = NS). Antithrombin III activity decreased at <em>2</em>4 and 48 hours (baseline, <em>1</em>08%; <em>2</em>4 hours, 97%; 48 hours, 95%; P < .000<em>1</em>). Hence, in patients with acute coronary syndromes, intravenous heparin at a dose reaching an activated partial thromboplastin time that adequately suppresses thrombin activity does not suppress increased thrombin generation.

Increased thrombogenicity of drug-eluting stents (DESs) has recently been reported. The aim of the present study was to investigate the prothrombogenic effect of DESs and Bare stents, and determine factors predictive of acute stent thrombosis (AST) in preclinical experiments using new stent design or coating. Circulating pre- and post-stenting parameters of platelet activation (mean platelet volume, MPV; platelet distribution width, platelet large cell ratio), thrombin activation (thrombin-antithrombin complex, TAT and <em>prothrombin</em> <em>fragments</em>, F<em>1</em>+<em>2</em>), tissue factor antigen (TF-ag) and -activity (TF-act) and plasminogen activator inhibitor-<em>1</em> (PAI-<em>1</em>) were measured in <em>1</em>4<em>1</em> consecutive pigs. Stent implantations were performed after pretreatment with aspirin and clopidogrel with unfractionated heparin anticoagulation. Nineteen pigs (groups AST-DES, n = <em>1</em><em>2</em>; and AST-Bare, n = 7) died mean 6.3 +/- <em>2</em>.9 h after stent implantation from AST. The remaining <em>1</em><em>2</em><em>2</em> control (C) pigs (groups C-DES, n = 76, and C-Bare, n = 46) survived the <em>1</em>-month follow-up. Non-significantly elevated levels of post-stent F<em>1</em>+<em>2</em> and TAT were measured in AST groups. Post-stenting MPV was increased significantly in the groups ASTDES and AST-Bare as compared with the groups C-DES and C-Bare (<em>1</em><em>1</em>.73 +/- <em>1</em>.<em>1</em><em>2</em> and <em>1</em><em>1</em>.6 +/- 0.68 vs. 8.85 +/- 0.78 and 9.04 +/- 0.8<em>1</em> fL; p < 0.00<em>1</em>), similarly to TF-ag (<em>1</em>89.<em>1</em> +/- 87.5 and <em>1</em><em>2</em>7 +/- 34.9 vs. 4<em>2</em>.5 +/- <em>2</em>4.6 and 35.3 +/- 37.6 pg/ml; p < 0.00<em>1</em>, respectively), Tfact (3.<em>2</em>3 +/- 0.95 and <em>2</em>.73 +/- <em>1</em>.68 vs. <em>1</em>.43 +/- <em>1</em>.<em>1</em><em>2</em> and <em>1</em>.6<em>1</em> +/- <em>1</em>.3<em>1</em> pM; p < 0.0<em>1</em>, respectively) and PAI-<em>1</em> (99.<em>1</em> +/- <em>1</em>5.8 and 99 +/- <em>1</em>4.7 vs.53.4 +/- 40.<em>2</em> and 46.9 +/- 4<em>2</em>.4 ng/ml;p < 0.0<em>1</em>, respectively). Multivariate analysis revealed elevated post-stenting plasma levels of TF-ag (p = 0.0<em>1</em>6) and MPV (p = 0.00<em>1</em>) as independent risk factors for developing AST within the first <em>2</em>4 h in a porcine coronary stent model.

OBJECTIVE

The aim of the present study was to evaluate the effects of pravastatin treatment on lipid, inflammation, and coagulation parameters in patients suffering from myocardial infarction with or without carotid atherosclerotic lesions (groups <em>1</em> and <em>2</em>, respectively).

METHODS

In the first phase of the study, a cross-sectional comparison of lipid, inflammation, and coagulation parameters was performed between the patients and the control group (group 3). Highly significant differences in these parameters were observed, especially in group <em>1</em>. In the second phase of the study, we assessed the effects of a persistent reduction in cholesterol synthesis induced by increasing doses of pravastatin (<em>2</em>0 mg daily for 8 weeks and 40 mg daily for a further 8 weeks). In addition to the well-established lipid-lowering effect, significant changes in inflammation and coagulation parameters were observed. In particular, pravastatin at a dosage of <em>2</em>0 mg/ day significantly reduced only fibrinogen levels, while at a dosage of 40 mg/day significantly reduced factor VII, fibrinogen, prothrombin fragments <em>1</em> and <em>2</em>, thrombin-antithrombin complexes, tissue plasminogen activator antigen (tPA:Ag) before venous occlusion (b.o.), inhibitor of plasminogen activator activity (PAI) b.o., PAI activity after occlusion (a.o.), the human autoantibodies against oxidized low-density lipoprotein (LDL), and the c fraction of the third component system levels, and significantly increased tPA:Ag a.o. levels.

RESULTS

Our results show that in patients suffering from myocardial infarction the risk of thrombotic complications can be decreased with pravastatin, especially by larger doses. However, the relationship must be further investigated because the observed reductions in the hemostatic system and inflammatory response seemed to be dose dependent, while the effects of pravastatin treatment were not significantly correlated with total and LDL cholesterol changes.

BACKGROUND

A novel estradiol-based combined oral contraceptive (COC) is currently available in many countries worldwide, including Europe and the US. Based on previous studies, it is expected that this estradiol-based COC will have a reduced hepatic effect compared with COCs containing ethinylestradiol with regard to proteins controlling the hemostatic balance.

OBJECTIVE

The aim of this study was to compare the hemostatic effects of the estradiol valerate/dienogest COC with a monophasic low-estrogen dose COC containing ethinylestradiol/levonorgestrel.

METHODS

Healthy women aged <em>1</em>8-50 years were randomized to receive a COC containing estradiol valerate/dienogest (<em>2</em> days estradiol valerate 3 mg, 5 days estradiol valerate <em>2</em> mg/dienogest <em>2</em> mg, <em>1</em>7 days estradiol valerate <em>2</em> mg/dienogest 3 mg, <em>2</em> days estradiol valerate <em>1</em> mg, <em>2</em> days placebo) or ethinylestradiol 0.03 mg/levonorgestrel 0.<em>1</em>5 mg in a crossover study design. Women received each treatment for three cycles, with two washout cycles between treatments. The primary efficacy variables were the intra-individual absolute changes in <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> and D-dimer from baseline to cycle three.

RESULTS

Data from <em>2</em>9 women were assessed. Intra-individual absolute changes in <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> and D-dimer from baseline to cycle three were less pronounced with estradiol valerate/dienogest than with ethinylestradiol/levonorgestrel.

CONCLUSIONS

The novel COC containing estradiol valerate/dienogest had similar or less pronounced effects on hemostatic parameters than ethinylestradiol/levonorgestrel.

To investigate the association of left atrial (LA) spontaneous echo contrast with the hemostatic state in nonrheumatic atrial fibrillation (AF), we examined the plasma levels of <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> and fibrinopeptide A in 73 patients with chronic nonrheumatic AF undergoing transesophageal echocardiography and 38 age-matched normal subjects. The results support the theory that LA spontaneous echo contrast in nonrheumatic AF is associated with a hypercoagulable state, especially in patients with marked LA spontaneous echo contrast.

BACKGROUND

It remains controversial whether prophylactic anticoagulation for embolism is required in patients with atrial flutter (AFL) prior to and following cardioversion as in patients with atrial fibrillation. To evaluate the potential prothrombotic state following cardioversion of AFL, concentrations of hemostatic markers were determined before and after conversion to sinus rhythm (SR).

RESULTS

In <em>1</em><em>2</em> patients (mean age 68 years) with AFL who underwent transesophageal echocardiography in the plasma concentrations of markers for platelet activity (platelet factor 4 (PF4) and beta-thromboglobulin (beta-TG)), thrombotic status (thrombin-antithrombin III complex (TAT) and <em>prothrombin</em> <em>fragments</em> <em>1</em> and <em>2</em> (F<em>1</em>+<em>2</em>)) and fibrinolytic status (D-dimer and plasmin-alpha(<em>2</em>)-plasmin inhibitor complex (PIC)) were determined during AFL, and 3 days and 7 days after restoration of SR. Left atrial appendage (LAA) blood flow velocity was lower immediately after than before restoration of SR (<em>2</em>9+/-<em>1</em><em>1</em> vs 4<em>1</em>+/-<em>2</em>3 cm/s, p<0.05). Three patients developed left atrial spontaneous echo contrast immediately after restoration of SR. Although the concentrations of the markers of platelet activity did not change after restoration of SR, those of TAT and PIC increased 7 days after restoration of SR as compared with during AFL (p<0.05).

CONCLUSIONS

AFL patients have a potential risk for thromboembolism after restoration of SR and therefore anticoagulation might be required in selected patients.

BACKGROUND

Octapharma PPGmbH has recently modified its manufacturing process for solvent/detergent-treated plasma to incorporate a prion reduction step, in which a 3 log reduction has been demonstrated. The current study was undertaken to assess the impact of this procedure on haemostatic variables in the new product OctaplasLG in comparison with standard Octaplas.

METHODS

Production batches of standard Octaplas (n=4) and OctaplasLG (n=<em>1</em>6) were assessed for levels of coagulation factors, physiological protease inhibitors, markers of activation and procoagulant microparticles. Global haemostasis was assessed by a thrombin generation test (TGT) and rotational thromboelastometry (ROTEM).

RESULTS

Mean levels of factors: II, V, VII, IX, X, XI, XII and XIII, VWF:Ag, antithrombin, protein C and free protein S were all >75 u/dl. ADAMTS-<em>1</em>3 activity levels were normal. Factor VIII and VWF:RCo were >55 u/dl. TGT and ROTEM were similar in both preparations, and microparticles were present at negligible levels. Two units of OctaplasLG had slightly elevated levels of <em>Prothrombin</em> <em>Fragments</em> <em>1</em>+<em>2</em>, but D-Dimer and thrombin-antithrombin complexes were normal in all batches.

CONCLUSIONS

These studies indicate that the affinity chromatography procedure used in OctaplasLG does not appear to adversely affect the proven haemostatic quality of Octaplas, while offering a selective reduction in the concentration of pathological prion proteins.

BACKGROUND

An increased incidence of thromboembolic events has been described in patients with cancer. Cancer cells are attributed with producing procoagulant substances such as cysteine protease and tissue factor to activate factor X and factor VII, respectively. However, there are limited data on the pathogenesis behind this hypercoagulability state, and the thrombin generation, fibrinolytic system, and coagulation inhibition system during cancer are largely obscure. In this study, we investigated the changes of different steps of coagulation pathway in patients with non-small-cell lung cancer (NSCLC) and compared the data with those of healthy controls.

METHODS

Forty-four patients with NSCLC and 36 age-matched controls were recruited for this study. <em>Prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> (F <em>1</em> + <em>2</em>) were used as a marker of thrombin generation; thrombin-activatable fibrinolysis inhibitor (TAFI) immunologic activity level was measured for inhibition of the fibrinolytic system, and tissue factor pathway inhibitor (TFPI) activity was assessed for the coagulation inhibition system. In the patient group, the relationships between TAFI activity levels and patient parameters (age, sex, body mass index [BMI], histopathology, and stage) were evaluated.

RESULTS

The TAFI activity, F <em>1</em> + <em>2</em> levels, and TFPI activity were significantly higher in patients with lung cancer than in subjects in the control group (P < .05; P < .000<em>1</em>; and P < .000<em>1</em>; respectively). However, there were no statistically significant associations between TAFI activity levels and patient age, sex, BMI, histopathology, or stage of disease (P>> .05).

CONCLUSIONS

In this study, it was clearly shown that patients with lung cancer have hypercoagulable states and that the pathogenesis of thrombotic events in these patients is multifactorial. Increased TFPI is a reflection of thrombin activity in this patient group. Confirmatory studies with larger patient groups should be performed in this population.

BACKGROUND

Cardiac surgery with cardiopulmonary bypass (CPB) is associated with the activation of inflammatory mediators that possess prothrombotic activity and could cause postoperative haemostatic disorders. This study was conducted to investigate the effect of cardiac surgery on prothrombotic activity in children undergoing cardiac surgery for complex cardiac defects.

METHODS

Eighteen children (ages 3 to <em>1</em>63 months) undergoing univentricular palliation with total cavopulmonary connection (TCPC) (n = <em>1</em>0) or a biventricular repair (n = 8) for complex cardiac defects were studied. Prothrombotic activity was evaluated by measuring plasma levels of <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> (F<em>1</em>+<em>2</em>), thromboxane B<em>2</em> (TxB<em>2</em>), and monocyte chemoattractant protein-<em>1</em> (MCP-<em>1</em>). Anti-thrombotic activity was evaluated by measuring levels of tissue factor pathway inhibitor (TFPI) before, during, and after cardiac surgery.

RESULTS

In all patients, cardiac surgery was associated with a significant but transient increase of F<em>1</em>+<em>2</em>, TxB<em>2</em>, TFPI, and MCP-<em>1</em>. Maximal values of F<em>1</em>+<em>2</em>, TxB<em>2</em>, and MCP-<em>1</em> were found at the end of CPB. In contrast, maximal levels of TFPI were observed at the beginning of CPB. Concentrations of F<em>1</em>+<em>2</em> at the end of CPB correlated negatively with the minimal oesophageal temperature during CPB. Markers of prothrombotic activity returned to preoperative values from the first postoperative day on. Early postoperative TFPI levels were significantly lower and TxB<em>2</em> levels significantly higher in patients with TCPC than in those with biventricular repair. Thromboembolic events were not observed.

CONCLUSIONS

Our data suggest that children with complex cardiac defects undergoing cardiac surgery show profound but transient imbalance between pro- and anti-thrombotic activity, which could lead to thromboembolic complications. These alterations are more important after TCPC than after biventricular repair but seem to be determined mainly by low antithrombin III.

BACKGROUND

Measurements of <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> (F<em>1</em>+<em>2</em>), thrombin antithrombin III complexes (TAT) and D-dimer plasma levels have been proposed as non-invasive screening tests to exclude postoperative deep venous thrombosis (DVT). We investigated the diagnostic efficacy of these coagulation activation markers to rule out postoperative DVT in patients undergoing hip surgery under antithrombotic prophylaxis.

METHODS

In this substudy of a randomized double-blind thrombosis prophylaxis trial comparing three doses of desirudin (<em>1</em>0, <em>1</em>5 or <em>2</em>0 mg b.i.d.) with unfractionated heparin (5000 IU t.i.d.) we used ELISA procedures to measure F<em>1</em>+<em>2</em>, TAT and D-dimer in <em>1</em>59 patients undergoing total hip replacement at baseline (day 0) and on postoperative days <em>1</em>, 3 and 6. Bilateral venography was performed in all cases 8-<em>1</em><em>1</em> days after surgery.

RESULTS

For the F<em>1</em>+<em>2</em> assay sensitivity ranged from 73 to 83% in the three postoperative days investigated, and negative predictive value (NPV) from 68 to 74%. For TAT and D-dimer sensitivity ranged from 7<em>1</em> to 73% and from 7<em>1</em> to 83% and NPV from 6<em>1</em> to 65% and from 6<em>1</em> to 74% respectively.

CONCLUSIONS

In terms of sensitivity and NPV F<em>1</em>+<em>2</em> and D-dimer are equivalent and are superior to TAT. However, their accuracy is too low to rule out the presence of DVT after hip surgery under antithrombotic prophylaxis.

BACKGROUND

Unstable coronary artery disease (CAD) is a multi-factorial disease involving thrombotic and inflammatory processes. Short-term low molecular weight (LMW) heparin treatment reduces coagulation activity and clinical events. We investigated the influence of prolonged treatment on coagulation, fibrinolysis and inflammation.

RESULTS

Serial blood samples were obtained from 555 of <em>2</em>,<em>2</em>67 unstable CAD patients in the FRISC II study. Patients were treated with the LMW heparin dalteparin <em>1</em><em>2</em>0 IU kg(-<em>1</em>) s.c. twice daily for 5-7 days and randomized to placebo (n=<em>2</em>85) or gender and weight-adjusted doses of dalteparin (5,000 or 7,500 IU) twice daily (n=<em>2</em>70) for 3 months. Dalteparin persistently depressed coagulation activity with, when compared with placebo, lower median levels of factor VIIa (63 IU mL(-<em>1</em>) vs. 84 IU mL(-<em>1</em>)), <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> (0.86 nmol L(-<em>1</em>) vs. <em>1</em>.09 nmol L(-<em>1</em>)) and D-dimer (<em>2</em><em>1</em> microg L(-<em>1</em>) vs. 43 microug L(-<em>1</em>)) after 3 months, all P<0.0<em>1</em>. Reactivation of coagulation activity was observed after cessation of both short-term and prolonged dalteparin treatment. Higher levels of tPA/PAI-<em>1</em> complex (<em>1</em><em>1</em>.7 microg L(-<em>1</em>) vs. 6.5 microg L(-<em>1</em>), P<0.00<em>1</em>) and von Willebrand factor (<em>1</em>6<em>2</em>% vs. <em>1</em>36%, P<0.00<em>1</em>) were found during prolonged dalteparin treatment. Interleukin-6, C-reactive protein and fibrinogen levels were unaffected by dalteparin treatment.

CONCLUSIONS

Three months dalteparin treatment resulted in a sustained and pronounced reduction of coagulation activity, which corresponds to the observed reduction in death and myocardial infarction during the initial 6 weeks in the FRISC II study. The persistently elevated levels of tPA/PAI-<em>1</em> complex and von Willebrand factor might reflect effects on platelets and endothelial cells and thus contribute to the gradually decreased efficacy by prolonged dalteparin treatment in unstable CAD.

We compared the effect of simvastatin versus simvastatin combined with ezetimibe on hemostasis and inflammation after acute coronary events [acute coronary syndromes (ACS)]. In an investigator-initiated, double-blind, placebo-controlled, randomized study, patients with ACS were assigned to 40 mg/d of simvastatin + <em>1</em>0 mg/d of ezetimibe (n = <em>2</em>6) or 40 mg/d of simvastatin + placebo (n = <em>2</em>8) administered for <em>2</em> months. Markers of coagulation (<em>prothrombin</em> <em>fragments</em> <em>1</em>.<em>2</em>, thrombin-antithrombin complexes, free tissue factor pathway inhibitor), fibrinolysis [plasminogen activator inhibitor-<em>1</em>, clot lysis time (CLT)], platelet activation (soluble CD40 ligand, β-thromboglobulin, thromboxane B<em>2</em>), oxidative stress [8-iso-prostaglandin F<em>2</em>α (8-iso-PGF<em>2</em>α)], and inflammation (interleukin-6, interleukin-<em>1</em>8, and interleukin-<em>1</em>β) were measured within the first <em>1</em><em>2</em> hours of ACS and at <em>1</em> and <em>2</em> months of therapy. A final analysis comprised <em>2</em>0 patients in the simvastatin + ezetimibe group and <em>2</em>6 patients in the simvastatin + placebo group. Both groups were similar with regard to demographics, risk factors, medications, and routine laboratory results. Inflammatory, coagulation, and platelet markers did not differ between both treatment groups at all time points. Reductions in low-density lipoprotein cholesterol, CLT, plasminogen activator inhibitor-<em>1</em>, and 8-iso-PGF<em>2</em>α were significantly greater (by <em>1</em>0%, 8.7%, <em>1</em>7.5%, and <em>2</em><em>2</em>.4%) in the simvastatin + ezetimibe group after <em>1</em> month, with further decreases in CLT and 8-iso-PGF<em>2</em>α at <em>2</em> months (all P < 0.05). These changes were not associated with lipid and inflammatory parameters. In conclusion, compared with simvastatin alone, simvastatin + ezetimibe results in a greater suppression of oxidative stress and enhanced fibrinolysis in patients with ACS, indicating that ezetimibe might exert cholesterol-independent actions in humans (NCT007<em>2</em>58<em>2</em>9).

BACKGROUND

Components of the renin-angiotensin-aldosterone system (RAAS) and a prothrombotic state are predictors of cardiovascular events in hypertensive patients. A relationship between the RAAS and the coagulation/fibrinolytic systems has been demonstrated, but its clinical relevance in hypertension is unclear. We investigated the relationships of the RAAS and the hemostatic system with hypertensive organ damage.

METHODS

Plasma components of the RAAS and parameters that directly assess the activation of coagulation and fibrinolysis were measured in <em>2</em>47 essential hypertensive patients in whom the extent of organ damage had been characterized at the cardiac, renal, and vascular level.

RESULTS

Positive association with increasing plasma renin activity (PRA) was demonstrated for plasma fibrinogen, D-dimer, and plasminogen activator inhibitor-<em>1</em> (PAI-<em>1</em>) levels. PRA was directly correlated with plasma aldosterone, fibrinogen, d-dimer, and PAI-<em>1</em>. The relationship of PRA with fibrinogen and PAI-<em>1</em> remained significant after correction for age, gender, duration of hypertension, and smoking status. Plasma aldosterone levels were directly correlated with fibrinogen, D-dimer, and PAI-<em>1</em>, whereas plasma angiotensin-converting enzyme was not related with any of the coagulation parameters. Elevated PRA, aldosterone, fibrinogen, D-dimer, <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em>, and PAI-<em>1</em> levels were associated with clinical and/or instrumental evidence of hypertension-related cardiac and renal damage. Both fibrinogen and PAI-<em>1</em> were independent predictors of the presence of organ damage and their inclusion in a multivariate model eliminated PRA and aldosterone as independent predictors.

CONCLUSIONS

A strong and independent association exists between renin, aldosterone, and markers of a prothrombotic state in essential hypertension. This relationship might contribute to the development of hypertensive organ damage.

Studies suggest that thrombosis is important in the progression of atherosclerotic lesions. The biochemical markers <em>prothrombin</em> <em>fragment</em> <em>1</em>-<em>2</em> and fibrinopeptide A reflect in vivo thrombin generation and activity, respectively. As such, they are markers that might be associated with cardiovascular risk. From the Cardiovascular Health Study, a cohort study of 5<em>2</em>0<em>1</em> persons over 65 years of age, 399 persons free of clinical cardiovascular disease (CVD) at the baseline examination were selected for study of specialized markers of hemostasis. We report the cross-sectional relationships of the thrombin markers to CVD risk factors and measures of subclinical CVD. The range of <em>fragment</em> <em>1</em>-<em>2</em> <em>2</em> was 0.<em>1</em><em>2</em> to 0.85 nmol/L. The range of fibrinopeptide A was 0.9 to 44.<em>1</em> micrograms/L. High levels of <em>fragment</em> <em>1</em>-<em>2</em> and fibrinopeptide A were associated with age, with levels higher in women than men. <em>Fragment</em> <em>1</em>-<em>2</em> was associated with smoking; high levels of triglyceride, creatinine, and C-reactive protein; and low levels of glucose. Fibrinopeptide A was associated with high C-reactive protein and apolipoprotein(a) and lower ankle-brachial index. There were no significant associations of the thrombin markers with race, fibrinogen, alcohol consumption, diabetes, or most measures of subclinical CVD. Study findings support a hypothesis that there are physiological interrelationships between cardiac risk factors, hemostasis, inflammation, and progression of atherosclerosis.

Activation of factor (F)VII by tissue factor may represent a critical event during plaque rupture in acute coronary syndromes. Patients with combined hyperlipemia are at high risk for developing coronary heart disease and their tendency to thrombosis may be accelerated during postprandial hyperlipemia. In the present double-blind, placebo-controlled parallel study, 4<em>2</em> patients with combined hyperlipemia and serum triglycerides between <em>2</em>.0 and <em>1</em>5.0 mmol L(-<em>1</em> )and serum cholesterol >5.3 mmol L-<em>1</em> at the end of a 3-month dietary run-in period were treated with atorvastatin at <em>1</em>0 mg day-<em>1</em> for at least <em>1</em>0 weeks. During the last 5 weeks the patients were randomized into two groups receiving <em>1</em>.68 g day(-<em>1</em>) omega-3 fatty acids (omega-3 FA) or placebo (corn oil). The fasting levels of FVII antigen (FVII-Ag) and FVII coagulant activity (FVII:C) were high compared with healthy males. The fasting levels of activated FVII (FVIIa) and FVII-Ag correlated both to serum triglycerides and apolipoprotein A<em>1</em> (apoA<em>1</em>). FVIIa and FVII:C increased during postprandial hyperlipemia. This increase of FVIIa correlated to the fasting triglyceride and apoA<em>1</em> levels, but not to the degree of postprandial hypertriglyceridemia. The concentrations of fasting FVIIa in these patients were reduced in parallel with a reduction of fasting triglycerides by treatment with atorvastatin + placebo. This treatment also reduced the postprandial level of FVIIa. omega-3 FA in addition to atorvastatin further reduced FVIIa concentrations, fasting and postprandially, and also significantly reduced FVII:C and FVII-Ag during postprandial hyperlipemia. <em>Prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> (F<em>1</em> + <em>2</em>) increased during postprandial hyperlipemia. This increase was significantly reduced after treatment with atorvastatin plus omega-3 FA. The increase of F<em>1</em> + <em>2</em> measured as incremental area under the curve (iAUC) during postprandial hyperlipemia correlated to the fasting levels of FVIIa, FVII:C and FVII-Ag and also to the levels of these factors during postprandial lipemia. In conclusion, patients with combined hyperlipemia are at risk for activation of the coagulation system, particularly during postprandial lipemia. This activation may be significantly reduced by statins and omega-3 FA.

The aim of the present study was to investigate the reactivity of immunoreagents developed for clinical applications in humans in different animal species (hen, mouse, rat, rabbit, guinea-pig, dog, pig, sheep, baboon). <em>Prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em>, thrombin-antithrombin III complex and fibrinopeptide A were tested for coagulation, platelet factor 4 and beta-thromboglobulin for platelet activation, glycoprotein IIb-IIIa, glycoprotein Ib and P-selectin for platelet membrane glycoproteins, D-dimers for fibrinolysis, thrombomodulin for activation of endothelial cells and thrombospondin and von Willebrand factor for adhesive proteins. <em>Prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em>, platelet factor 4, beta-thromboglobulin and D-dimers were revealed only in baboons. Fibrinopeptide A was well detected in baboons but weakly in mice, dogs, pigs and sheep. Whereas glycoprotein IIb-IIIa was revealed on guinea-pig, dog and sheep platelets and glycoprotein Ib on rabbit and dog platelets, P-selectin and thrombomodulin were never detected. Thrombospondin was revealed in hens, mice, rats, guinea-pigs, pigs, sheep and baboons and von Willebrand factor in mice, rats, guinea-pigs, dogs, pigs, sheep and baboons. Interestingly, thrombin-antithrombin III complex (TAT) was detected in all species tested except the hen. A time- and dose-dependent increase in TAT was observed when rats, dogs or pigs were infused with thromboplastin (4.5-450 microliters/kg/h), while administration of hirudin (<em>1</em> mg/kg) abolished this TAT generation. Thus, the TAT immunoassay could provide a tool for the screening of antithrombotic drugs in a number of animal species. However, the possibility of using a wider panel of human immunoreagents would appear to be restricted to baboons which display good species cross-reactivity.

The optimal procedure for withdrawal of warfarin in patients with deep vein thrombosis (DVT) is still not defined. Rebound thrombin generation, which occurs after the withdrawal of warfarin, has been said to be associated with early recurrence of DVT. The aim of this study was to compare two procedures for warfarin withdrawal after the first episode of DVT with respect to rebound thrombin generation. Forty-one consecutive patients were randomly assigned to abrupt withdrawal of warfarin (group A), or to an additional month of warfarin, at the fixed dose of <em>1</em>.<em>2</em>5 mg/day (group B). Plasma samples were withdrawn for the assay of <em>prothrombin</em> <em>fragment</em> F<em>1</em>+<em>2</em> (F<em>1</em>+<em>2</em>), protein C, factor VII and International Normalized Ratio (INR), before any anticoagulant treatment (I), during initial heparin (II) and full dose warfarin (III), at the end of full dose warfarin (IV) and then <em>1</em> (V), 4 (VI), 5 (VII) and 9 (VIII) weeks after randomization. The mean duration of full-dose warfarin treatment, the mean warfarin dose and the mean INR during full-dose warfarin treatment were similar in the two groups. A decrease in F<em>1</em>+<em>2</em> was observed during heparin and warfarin treatment (II, <em>1</em>.7 nmol/ml; III, <em>1</em>.0 nmol/ml; IV, 0.7 nmol/ml; versus I, 3.5 nmol/ml; P<0.0<em>1</em>). After the withdrawal of warfarin, an increase in F<em>1</em>+<em>2</em> was observed in both groups, but without significant statistical differences (group A: V, <em>1</em>.<em>2</em> nmol/ml; VI, <em>1</em>.5 nmol/ml; VII, <em>1</em>.6 nmol/ml; VIII, <em>1</em>.<em>1</em> nmol/ml; group B: V, <em>1</em>.3 nmol/ml; IV, <em>1</em>.5 nmol/ml; VII, <em>1</em>.4 nmol/ml; VIII, <em>1</em>.4 nmol/ml). No significant difference between the two groups was observed in the recovery of protein C and factor VII. Four patients experienced a recurrence of DVT, three in group B and one in group A. Our findings confirm that rebound thrombin generation occurs in patients with DVT after the withdrawal of warfarin. Rebound thrombin generation is not reduced by a low, fixed dose of warfarin.

BACKGROUND

Among patients without chronic kidney disease, resistin, an adipocytokine, has been related to inflammatory markers, coronary artery disease, and cardiovascular disease in the metabolic syndrome. Moreover, resistin up-regulates adhesion molecules. Since inflammation and endothelial cell damage or injury are invariably associated with thrombosis, atherosclerosis, and their major clinical consequences, resistin may play a role to link inflammation and CVD. The aim of this study was to correlate resistin with markers of inflammation and endothelial cell injury in 96 kidney allograft recipients.

METHODS

We measured resistin and the following markers of endothelial function/injury: vWF, thrombomodulin, VCAM, hsCRP, tumor necrosis factor alpha (TNFalpha), and interleukin-6 (IL-6).

RESULTS

Triglycerides, CRP (assessed by high-sensitivity method), phosphate, creatinine, IL-6, TNFalpha, vWF, <em>prothrombin</em> <em>fragments</em> <em>1</em> + <em>2</em>, and resistin were elevated among kidney transplant recipients compared with the control group. Kidney allograft recipients with coronary artery disease displayed significantly higher resistin levels than those in patients without this complication. Upon univariate analysis resistin levels in kidney allograft recipients were related to hsCRP, IL-6, thrombomodulin, red blood cell count, white blood cell count, platelet count, creatinine, urea, VCAM, CSA, dose and eGFR. Upon multiple regression analysis, resistin was independently related only to creatinine, hsCRP, and white blood cell count in kidney allograft recipients.

CONCLUSIONS

The relation of elevated resistin levels to markers of inflammation may represent a novel link between these conditions and adipocytokines. Renal function was a major determinant of elevated resistin in kidney allograft recipients.

BACKGROUND

Pre-eclampsia is associated with increased placental debris circulating in maternal plasma.

OBJECTIVE

This study related placental debris to maternal markers of coagulation and endothelial activation in pre-eclampsia.

METHODS

Circulating fetal corticotrophin-releasing hormone (CRH) mRNA and phosphatidylserine (PS)-exposing microparticles were assayed in third trimester plasma from women with pre-eclampsia (n = 3<em>2</em>) and controls (n = 3<em>2</em>) matched for age, body mass index, parity, and gestational age at sampling. Markers of maternal hemostasis and endothelial function were assessed.

RESULTS

Fetal CRH mRNA levels were higher in pre-eclampsia [mean 0.75 (SD <em>2</em>.77) CRH/glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA ratio] than in control pregnancies [0.<em>2</em>0 (0.74), P = 0.0<em>1</em>4]. PS-exposing microparticle levels were not different between the groups. Women with pre-eclampsia had higher levels of tissue factor pathway inhibitor (TFPI), <em>prothrombin</em> F(<em>1</em>+<em>2</em>) <em>fragment</em> (F(<em>1</em>+<em>2</em>)), factor XIIa, soluble vascular cell adhesion molecule <em>1</em>, von Willebrand factor and plasminogen activator inhibitor <em>1</em> than controls. Fetal CRH mRNA correlated with TFPI in pre-eclampsia and control groups (r = 0.38, P = 0.03<em>1</em>, and r = 0.37, P = 0.039, respectively). Fetal CRH mRNA correlated with FVII activity (r = 0.43, P = 0.0<em>1</em>7) and PS-exposing microparticles correlated inversely with F(<em>1</em>+<em>2</em>) (r = -0.64, P < 0.00<em>1</em>) in pre-eclampsia.

CONCLUSIONS

Placental debris, assessed by fetal CRH mRNA levels in maternal blood, is related to coagulation potential, i.e. FVII activity, but not to markers of coagulation or endothelial activation in pre-eclampsia.

The implantation of immuno-isolated recombinant cell lines secreting a therapeutic protein in alginate microcapsules presents an alternative approach to gene therapy. Its clinical efficacy has recently been demonstrated in treating several genetic diseases in murine models. However, its application to humans will depend on the long-term structural stability of the microcapsules. Based on previous implantations in canines, it appears that survival of alginate-poly-L-lysine-alginate microcapsules in such large animals is short-lived. This article reports on the biological factors that may have contributed to the degradation of these microcapsules after implantation in dogs. Alginate microcapsules coated with poly-L-lysine or poly-L-arginine were implanted in subcutaneous or intraperitoneal sites. The retrieved microcapsules showed a loss of mechanical stability, as measured by resistance to osmotic stress. The polyamino acid coats were rendered fragile and easily lost, particularly when poly-L-lysine was used for coating and the intraperitoneal site was used for implantation. Various plasma proteins were associated with the retrieved microcapsules and identified with western blotting to include Factor XI, Factor XII, prekallikrein, HMWK, fibrinogen, plasminogen, ATIII, transferrin, alpha-<em>1</em>-antitrypsin, fibronectin, IgG, alpha-<em>2</em>-macroglobulin, vitronectin, <em>prothrombin</em>, apolipoprotein A<em>1</em>, and particularly albumin, a major Ca-transporting plasma protein. Complement proteins (C3, Factor B, Factor H, Factor I) and C3 activation <em>fragments</em> were detected. Release of the amino acids from the microcapsule polyamino acid coats was observed after incubation with plasma. indicating the occurrence of proteolytic degradation. Hence, the loss of long-term stability of the polyamino acid-coated alginate microcapsules is associated with activation of the complement system, degradation of the polyamino acid coating, and destabilization of the alginate core matrix, probably through loss of calcium-mediated ionic cross-linking of the guluronic acid polymers in the alginate. These destructive forces may be slightly mitigated by using poly-L-arginine instead of poly-L-lysine for coating and by implanting in a subcutaneous instead of an intraperitoneal site. However, the long-term stability of such devices may require significant improvements in the microcapsule polymer chemistry to withstand such biological impediments.

Patients undergoing liver transplantation have complex changes in their hemostatic system, and the net effect of these changes appears to be a "rebalanced" hemostatic profile. Recently, a process called NETosis in which a neutrophil expels DNA and proteins that form a weblike structure, has been described as a mechanism of pathogen entrapment. Increasing evidence suggests a pivotal role for neutrophil extracellular traps (NETs) and their main component, cell-free DNA (cfDNA), in activation of coagulation. Because liver transplantation is associated with substantial (hepatocyte) cell death and intrahepatic neutrophil accumulation, NETs might play an important role in the hemostatic balance during liver transplantation. Here, we determined markers for NETs in the plasma of patients undergoing a liver transplantation and examined their association with activation of coagulation. Markers for NETs and markers for activation of coagulation were determined in serial plasma samples taken from patients undergoing a liver transplantation (n = <em>2</em><em>1</em>) and compared with plasma levels in healthy controls. We found perioperative increases of markers for NETs with levels of cfDNA and nucleosomes that peaked after reperfusion and myeloperoxidase (MPO)-DNA complexes that peaked during the anhepatic phase. CfDNA and nucleosome levels, but not MPO-DNA levels, correlated with <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> and thrombin-antithrombin complex levels, which are established markers for activation of coagulation. Neutrophils undergoing NETosis were observed by immunostainings in postreperfusion biopsies. In conclusion, although NETosis occurs during liver transplantation, the majority of circulating DNA appears to be derived from cell death within the graft. The perioperative increases in cfDNA and nucleosomes might contribute to the complex hemostatic rebalance during liver transplantation.

Junin virus, an arenaviridae, is the etiological agent of Argentine hemorrhagic fever. In addition to thrombocytopenia, patients present several alterations in both the blood coagulation and the fibrinolytic system, but diffuse intravascular coagulation could not be demonstrated. To investigate further the activation status of the two systems, levels of thrombin-antithrombin complexes (TAT), <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em>, protein C, total and free protein S, C4bBP, antithrombin III, t-PA, PAI-<em>1</em> and D-dimer were measured. Fourteen patients with a confirmed diagnosis of Argentine hemorrhagic fever were included in the study, <em>2</em> were severe, 3 moderate and 9 mild clinical cases, but hemorrhages were slight throughout. Blood samples were collected for 6 consecutive days on admission and on remission. At admission TAT and F<em>1</em> + <em>2</em> levels were increased in <em>1</em>3/<em>1</em>4 patients, reaching 0.33 nM (0.06-0.87) and <em>2</em>.<em>1</em>6 nM (0.96-6.5), respectively. PC was low in 4 cases, fPS in 6 and tPS in <em>2</em>, whereas C4bBP and ATIII values were within normal range. t-PA and D-dimer levels were high in <em>1</em><em>1</em>/<em>1</em>4 patients, reaching <em>2</em>0 ng/ml (<em>2</em>.7-<em>1</em>06) and <em>1</em>660 ng/ml (877-3780) respectively, while PAI-<em>1</em> was considerably increased in the <em>2</em> severe cases and normal in the remainder. These results suggest low level though persistent process of blood coagulation and fibrinolysis activation in this viral hemorrhagic disease. We believe these abnormalities may lead to the well described bleeding manifestations in these patients.