BACKGROUND

Helicobacter pylori and some of its virulence factors stimulate human blood mononuclear cells (MNC) in vitro to produce tissue factor (TF) and plasminogen activator inhibitor-<em>2</em> (PAI-<em>2</em>). In this study we investigated the procoagulant-fibrinolytic potential of blood MNC in patients with H. pylori infection. In the same patients we also evaluated the coagulation-fibrinolysis profile in gastric tissue and in plasma.

RESULTS

The production of TF and PAI-<em>2</em> was evaluated in 6<em>1</em> patients with dyspepsia, 3<em>1</em> positive and 30 negative for H. pylori infection. TF expressed by MNC and PAI-<em>2</em> accumulation in cell culture medium after incubation for <em>2</em>0 h at 37 degrees C were significantly higher in H. pylori(+) than in H. pylori(-) patients and were significantly correlated. TF and PAI-<em>2</em> content in extracts of gastric mucosa was similar in the two groups whereas lower levels of tissue plasminogen activator (t-PA) and thrombomodulin (TM) antigens were found in the antrum of H. pylori(+) patients. No difference between the groups was observed in plasma thrombus precursor protein, <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em>, D-dimer, t-PA, PAI-<em>1</em>, TM and thrombin activatable fibrinolysis inhibitor.

CONCLUSIONS

H. pylori infection is associated with functional abnormalities of blood MNC resulting in the coordinate expression of TF and antifibrinolytic activity. Changes in cell coagulation-fibrinolysis balance may represent a link between H. pylori infection and ischemic heart disease.

Inherited activated protein C (APC) resistance is a newly described pathological condition associated with familial thrombophilia. A recent report on family with APC resistance showed increased levels of <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> (F<em>1</em> + <em>2</em>) in the affected individuals. No data concerning thrombin-antithrombin complex (TAT) levels in patients with inherited APC resistance are presently available. The aim of this study was to assess the plasma levels of F<em>1</em> + <em>2</em> and TAT in patients with inherited APC resistance due to factor V (F.V) Leiden mutation and to evaluate F<em>1</em> + <em>2</em> and TAT levels in symptomatic and asymptomatic patients with the defect ('carriers') as compared to their family members having no evidence of F.V Leiden mutation ('non-carriers'). One hundred and twenty-nine individuals belonging to 30 families with inherited APC resistance due to F.V Leiden mutation were studied. F<em>1</em> + <em>2</em> and TAT levels were determined using two commercially available ELISA kits and cut-off values were defined as the higher limits of normal ranges obtained in healthy volunteers. Out of the <em>1</em><em>2</em>9 family members investigated, 36 were non-carriers, 85 were heterozygous and eight homozygous for F.V Leiden mutation. Thrombosis had occurred in <em>2</em>/36 (6%) non-carriers, in 36/85 (4<em>2</em>.3%) heterozygous and in 5/8 (63%) homozygous. Median levels of F<em>1</em> + <em>2</em> and TAT were above cutoff values in carriers, whereas they were below in non-carriers. An overall percentage of 68.8% of carriers exhibited F<em>1</em> +<em>2</em> levels above the cut-off value as compared to 38.9% of non-carriers. For TAT, an overall percentage of 63.4% of carriers presented with levels above the cut-off compared with <em>2</em>8% of non-carriers. In conclusion, patients with inherited F.V Leiden mutation may exhibit increased levels of F<em>1</em> + <em>2</em> and TAT. There are no differences in F<em>1</em> + <em>2</em> and TAT median levels among symptomatic and asymptomatic carriers. The percentage of carriers of F.V Leiden with levels of F<em>1</em> + <em>2</em> and TAT above cut-off appears to be higher than that found in other clotting inhibitors defects and in this respect the defect might be considered different. However, these findings and the presence of high percentage of non-carriers presenting with increased F<em>1</em> + <em>2</em> and TAT levels may suggest the possible coexistence in these families of other unknown defects predisposing to thrombosis.

BACKGROUND

Benign Intracranial Hypertension (BIH) may be caused, at least in part, by intracranial sinus thrombosis. Thrombosis is normally due to derangements in blood coagulation cascade which may predispose to abnormal clotting activation or deficiency in natural inhibitors' control. The aim of the study is to examine the strength of the association between risk factors for thrombosis and BIH.

METHODS

The incidence of prothrombotic abnormalities among a randomly investigated cohort of <em>1</em>7 patients with BIH, was compared with 5<em>1</em> healthy subjects matched for sex, age, body mass index, height and social background.

RESULTS

The number of subjects with protein C deficiency was significantly higher in patients than in controls (3 vs <em>1</em>, p < .00<em>1</em>; Fisher Exact Test). Moderate to high titers of anticardiolipin antibodies (beta<em>2</em>-Glycoprotein type I) were found in 8 out of <em>1</em>7 patients. Increased plasma levels of <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em>, fibrinopeptide A (FPA), and PAI-<em>1</em> were demonstrated in patients group (5.7 +/- <em>1</em>.<em>1</em>5 nM vs 0.45 +/- 0.35 nM; 8.7 +/- <em>2</em>.5 ng/mL vs <em>2</em>.<em>2</em> +/- <em>1</em>.<em>2</em>5 ng/mL; 45.7 +/- <em>1</em><em>2</em>.5 ng/mL vs 8.5 +/- 6.7 ng/mL, respectively; p < .00<em>1</em>; Fisher Exact Test). Gene polymorphisms for factor V Leiden mutation, <em>prothrombin</em> mutation <em>2</em>0<em>2</em><em>1</em>0 A/G, MTHFR 677 C/T, PAI-<em>1</em> 4G/5G, ACE I/D were detected in <em>1</em>3 patients.

CONCLUSIONS

In agreement with other authors our data suggest a state of hypercoagulability in BIH associated with gene polymorphisms. Our findings also showed that mutations in cardiovascular genes significantly discriminate subjects with a BIH history. The association between coagulation and gene derangements, usually regarded to as cryptogenic, may suggest a possible pathogenetic mechanism in BIH. So, a prothrombotic tendency may exist that would, at least in part, explain some cases of BIH. Although based on a small population, these findings raise the exciting possibility of using these haemostatic factors as markers for selecting high-risk subjects in BIH disease.

OBJECTIVE

It has been suggested that high doses of statins can be more effective in reducing the incidence of new cardiovascular events than conventional doses. The present study analyzed the effect of increasing the atorvastatin dose to 80 mg/day on indices of inflammation (C-reactive protein or CRP), thrombogenesis (<em>prothrombin</em> <em>fragment</em> [F<em>1</em>+<em>2</em>]) and fibrinolysis (tissue-type plasminogen activator antigen, t-PA, and its inhibitor PAI-<em>1</em>) in high-risk patients with ischemic heart disease.

METHODS

We studied <em>2</em>7 patients with high-risk coronary heart disease who had lipid levels above those recommended despite treatment with atorvastatin at 40 mg/day. At baseline, patients were compared with <em>2</em><em>1</em> normocholesterolemic subjects without arteriosclerotic disease. Twenty-four patients were reevaluated 3 months after the atorvastatin dose was increased to 80 mg/day.

RESULTS

The CRP, F<em>1</em>+<em>2</em>, t-PA and PAI-<em>1</em> levels were significantly higher in patients than control subjects (all P<.05). After the atorvastatin dose was increased, significant reductions in CRP, F<em>1</em>+<em>2</em>, and PAI-<em>1</em> levels were observed (P<.05). There was a significant positive correlation between the reduction in cholesterol level and that in F<em>1</em>+<em>2</em> (r=0.43; P=.0<em>2</em>3). No other significant correlations were found.

CONCLUSIONS

In a group of patient with high-risk heart disease and elevated lipid levels, increasing the atorvastatin dose led to significant improvements in inflammatory, thrombogenic, and hypofibrinolytic states.

The aim of this prospective, non-randomised study was to investigate haemostatic system alterations in patients undergoing open (OC) and laparoscopic cholecystectomy (VLC). In addition, we also measure the plasma cytokine profile to explore any relationship between changes in plasma cytokine levels and the postoperative coagulation profile. From July <em>2</em>005 to March <em>2</em>007, 7<em>1</em> patients were non-randomly assigned to open (group <em>1</em>) or laparoscopic cholecystectomy (group <em>2</em>). <em>Prothrombin</em> <em>fragment</em> <em>1</em>.<em>2</em> (F<em>1</em>.<em>2</em>), thrombin-antithrombin (TAT), fibrinogen, soluble fibrin, antithrombin III (AT), protein C, plasminogen and D-dimer levels were measured at baseline and at <em>1</em>, <em>2</em>4, 48 and 7<em>2</em> hours postoperatively. Serial serum levels of IL-<em>1</em> beta and IL-6 were measured by colorimetric ELISA. Plasma levels of F<em>1</em>.<em>2</em>, TAT, fibrinogen, soluble fibrin and D-dimer increased significantly in group <em>1</em>. Plasma levels of AT, protein C, plasminogen decreased in both groups. In the OC group, the serum IL-<em>1</em> beta and IL-6 levels began to increase significantly as early as <em>1</em> hour after the start of the operation, peaking at hour 6. The surge in circulating cytokine levels, commonly found in the postoperative period, is shown to be capable of inducing a hypercoagulability state and there is a positive correlation between IL-6 levels and hypercoagulability. In our study only mild hypercoagulability was observed in patients undergoing laparoscopic cholecystectomy. In conclusion, the correlation between cytokine levels and coagulation activation may be related to the type of surgery performed. Our present knowledge of the effect of laparoscopy upon coagulation and fibrinolysis is incomplete and based on only a few studies; for this reason further studies are required to investigate these aspects.

We chose to evaluate whether or not a state of biochemical hypercoagulability was present in 74 individuals (69 heterozygotes and 5 homozygotes) resistant to activated protein C (APC) due to the Arg506 ->> Gln mutation in the factor V gene. To this end, plasma levels of two markers of thrombin formation, <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> (F<em>1</em>+<em>2</em>) and thrombin-antithrombin complexes (TAT) were measured. High levels of F<em>1</em>+<em>2</em> and TAT were found in 3<em>2</em>% and <em>2</em>3% of APC-resistant individuals vs 4% in controls. The levels of these markers tended to be particularly elevated in three homozygous subjects. A significant positive correlation between F<em>1</em>+<em>2</em> and TAT was present in APC-resistant individuals. No relationship between marker values and the previous occurrence of thrombotic episodes was found. Therefore, by measuring F<em>1</em>+<em>2</em> and TAT a state of biochemical hypercoagulability has been identified in about one-third of APC-resistant individuals. This frequency is similar to that previously observed in comparable individuals with inherited deficiencies of protein C and protein S, which are usually associated with a stronger thrombotic tendency than APC-resistant individuals.

We measured plasma levels of soluble fibrin (SF) in 98 patients suspected of having disseminated intravascular coagulation (DIC) using a newly developed enzyme-linked immunosorbent assay (ELISA) and investigated the correlations between SF determinations and measurements of other hemostatic molecular markers to determine the diagnostic usefulness of determinations of SF. Patients were classified into four groups according to their clinical and laboratory findings: overt DIC (n =33), subclinical DIC (n =<em>2</em>3) hypercoagulability (n =<em>2</em><em>2</em>), and non-DIC (n =<em>2</em>0). SF levels were significantly higher in patients with overt DIC compared with the other three groups and were significantly higher in the subclinical DIC and hypercoagulability groups compared with the non-DIC patients. SF levels increased significantly with each increase in the clinical stage. Although levels of thrombin-antithrombin III complex (TAT), <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> (PF <em>1</em>+<em>2</em>), cross-linked fibrin degradation products (XDP), and plasmin-antiplasmin complex (PAP) were significantly increased in patients with overt DIC compared with non-DIC patients, the values of these hemostatic molecular markers did not consistently show an increase in association with advances in the disease stage. Plasma levels of SF in patients with overt DIC showed a positive correlation with levels of TAT, XDP,and FDP(E), but not with PF<em>1</em>+<em>2</em> and PAP. Analysis of receiver-operating characteristic curves showed that the sensitivity and specificity of SF were similar to those of XDP for diagnosis of DIC. The sensitivity and specificity of SF for diagnosis of overt DIC were both above 90% when the cut-off value was set at 65 mu g/ml.plasma levels of SF were also increased in patients with extravascular fibrin formation without DIC. Our findings suggest that measurement of plasma levels of SF by this ELISA method is useful for the diagnosis of DIC and the evaluation of the patient's clinical status.

Ischemic electrocardiographic changes were recorded within <em>2</em> hours of admission using a <em>1</em><em>2</em>-lead electrocardiographic continuous monitor with a <em>2</em>0-second scanning interval and an alarm mode for asymptomatic events. Blood samples were obtained at admission and at the moment of asymptomatic events (group A). In the other patients who did not develop ischemia, a second blood sample was taken <em>1</em><em>2</em> hours later (group B). We determined <em>prothrombin</em> time, activated partial thromboplastin time, clotting factor VIII activity, tissue plasminogen activator activity, tissue plasminogen activator inhibitor-<em>1</em>, cross-linked fibrin degradation product, and thrombin-antithrombin III complexes. There was a statistically significant difference between group A and B patients when the basal samples were analyzed for thrombin-antithrombin III (p = 0.046) and d-Dimer (p = 0.005). <em>Prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> were significantly reduced, and d-Dimer was elevated when basal blood samples were compared with the second sample in patients who developed silent events (p = 0.008 and 0.055, respectively). A plasma concentration of thrombin-antithrombin III complex was also significantly decreased when sample <em>2</em> was compared with the basal blood sample (p = 0.039). Five recurrent episodes of angina and <em>2</em> nonfatal infarctions occurred, and 4 urgent revascularization procedures were performed in group A. In group B, there was only <em>1</em> nonfatal infarction (p = 0.0<em>1</em>). The results of the present study suggest that a time-dependent thrombotic process is detectable in the blood stream as a cyclic movement. Further studies are needed to determine if some other factors, such as intensive shear stress in the vessel wall, may activate plaque instability during asymptomatic episodes.

OBJECTIVE

To investigate the effects of combined hormone replacement therapy (HRT) on various parameters of coagulation and fibrinolysis that may contribute to increased risk for venous thromboembolic events.

METHODS

Prospective, randomized, double-blind, placebo-controlled study.

METHODS

Academic hospital.

METHODS

Sixty-one healthy postmenopausal women with intact uterus.

METHODS

Patients were randomized to receive continuous combined HRT (estradiol, <em>2</em> mg/d, and norethisterone acetate, <em>1</em> mg/d) or placebo for 6 months.

METHODS

Markers of coagulation and fibrinolysis were measured before therapy and after 3 and 6 months of therapy.

RESULTS

The groups did not differ significantly in levels of prothrombin fragments <em>1</em> and <em>2</em> and thrombin-antithrombin III complex after 3 and 6 months of therapy. After 6 months of HRT, significant decreases in activity of antithrombin III and protein C and levels of plasminogen activator inhibitor-<em>1</em> antigen, tissue-type plasminogen activator antigen, and euglobulin clot lysis time and a significant increase in D-dimer level were found compared with placebo.

CONCLUSIONS

Continuous combined HRT for several months produced no net activation of coagulation but improved fibrinolysis in healthy postmenopausal women with no risk factors for venous thromboembolic events.

This randomized, double-blind, parallel-group study was performed to assess the effect of <em>1</em>-week treatment with 75 and 300 mg aspirin on thrombin generation. Eighteen healthy men, aged <em>2</em>0-<em>2</em>5 years, entered the study. After <em>1</em> week of aspirin treatment with a daily dose of 75 mg, bleeding time became prolonged by <em>1</em>0<em>2</em> s (P = 0.0<em>2</em>), and it was prolonged by <em>1</em>65 s with 300 mg (P = 0.0005). None of the doses of aspirin affected peripheral blood concentrations of <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> and fibrinopeptide A. At the site of microvascular injury, 75 mg aspirin led to a marked, about 60%, reduction in the total amount of thrombin generated (P = 0.04). A similar decrease was observed after 7-day treatment with 300 mg aspirin (P = 0.009). We conclude that the thrombin-lowering action of aspirin in the range between 75 and 300 mg daily given for 7 days is not dose dependent.

BACKGROUND

Ruptured abdominal aortic aneurysm is associated with a high operative mortality. Postoperative thrombosis related complications are common, a possible mechanism being activation of the coagulation system and endothelial stimulation. The aim of the present study was to investigate the coagulation activity preoperatively in patients with ruptured and nonruptured abdominal aortic aneurysm in relation to the clinical outcome with special regard to the influence of shock.

METHODS

Ninety-five patients with repair of infrarenal aortic aneurysm and forty-one controls without aneurysm matched by age, gender and smoking habits were studied. Thrombin-antithrombin (TAT), <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> (F <em>1</em>+<em>2</em>), and von Willebrand factor antigen (vWFAg) were measured.

RESULTS

There were significantly higher levels of TAT, F <em>1</em>+<em>2</em>, and vWFAg in patients operated for ruptured compared to nonruptured abdominal aortic aneurysm. The highest level of TAT and F <em>1</em>+<em>2</em> were detected in patients with rupture and shock.

CONCLUSIONS

The present data indicate a state of activated coagulation in patients with ruptured abdominal aortic aneurysm which is reinforced by shock.

In patients with thrombophilia caused by reduced physiological anticoagulation, renal transplant failure occurs more frequently. Previous studies showed the importance of the protein C system, a physiological anticoagulatory pathway that inhibits thrombus formation. However, excess activation of the hemostatic system also may result in thrombosis. The G<em>2</em>0<em>2</em><em>1</em>0A mutation in the <em>prothrombin</em> gene is such a prothrombotic risk factor that results in increased thrombus formation because of elevated factor II levels in plasma. We analyzed graft function in <em>2</em>70 consecutive patients who received 3<em>1</em><em>1</em> renal transplants. The presence of a normal or mutated <em>prothrombin</em> allele was determined by polymerase chain reaction amplification and restriction <em>fragment</em> length polymorphism analysis of genomic DNA. Demographic data were extracted from hospital records. Graft survival was calculated for patients with and without the G<em>2</em>0<em>2</em><em>1</em>0A mutation. We identified 9 patients heterozygous for the G<em>2</em>0<em>2</em><em>1</em>0A mutation in the <em>prothrombin</em> gene who had received a total of <em>1</em><em>2</em> renal transplants. Of these <em>1</em><em>2</em> transplants, <em>2</em> grafts were lost within the first year. Median graft survival for patients heterozygous for the <em>2</em>0<em>2</em><em>1</em>0A allele was 65.9 months (range, 0 to <em>1</em>0<em>1</em> months) compared with <em>1</em>49 months (range, 0 to <em>2</em>37 months) for patients homozygous for the normal <em>2</em>0<em>2</em><em>1</em>0 G allele (P = 0.0<em>2</em>). The G<em>2</em>0<em>2</em><em>1</em>0A mutation represented a <em>2</em>.95-fold (95% confidence interval, <em>1</em>.03 to 8.46) increase in risk for graft loss. Only <em>1</em> patient with this mutation achieved graft function exceeding <em>1</em>0<em>1</em> months. The G<em>2</em>0<em>2</em><em>1</em>0A mutation of the <em>prothrombin</em> gene is an independent risk factor for graft failure.

Purer factor IX (FIX) concentrates have been produced for the treatment of hemophilia B in the attempt to reduce the risk of thrombotic complications associated with the use of <em>prothrombin</em> complex concentrates. To evaluate ex vivo whether or not FIX concentrates activate the coagulation system in conditions associated with a high risk for thrombosis, we measured markers of hypercoagulability in <em>1</em>0 patients with hemophilia B who underwent surgery, mainly orthopedic procedures, covered by multiple concentrate infusions (40-80 U/kg/day). Postinfusion plasma levels of <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> and factor X activation peptide did not differ significantly from the presurgical levels, neither before nor after each concentrate dose. Therefore, it appears that prolonged treatment of patients with hemophilia B undergoing high risk surgical procedures with high doses of FIX concentrate does not cause systemic activation of coagulation. This suggests that purified FIX concentrates are preferable to <em>prothrombin</em> complex concentrates for conditions associated with an increased risk of thrombosis.

We investigated changes in blood coagulation in the coronary circulation after percutaneous transluminal coronary angioplasty (PTCA) and its clinical significance. We examined 43 patients with ischemic heart disease who underwent elective PTCA of isolated stenotic lesions in the left coronary artery. Ten patients underwent PTCA alone, <em>1</em>5 received percutaneous transluminal rotational atherectomy (PTRA) and <em>1</em>8 stent implantation. Blood samples were drawn from the coronary sinus before and immediately after PTCA, as well as 4 and <em>2</em>4 h later. Plasma levels of tissue factor (TF), thrombin-antithrombin III complex (TAT) and <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> (F <em>1</em>+<em>2</em>) were measured by enzyme-linked immunosorbent assay. Follow-up coronary angiography was performed 6 months after PTCA. Minimal luminal diameter was assessed by quantitative coronary angiography to evaluate late loss index. TF, TAT and F <em>1</em>+<em>2</em> levels in the coronary sinus blood showed significant increases <em>2</em>4 h after PTCA. A significant positive correlation was found between changes in TF levels <em>2</em>4 h after PTCA and late loss index 6 months after the procedure. TF levels in the coronary sinus blood were significantly higher in patients with late restenosis than in those without restenosis. These results suggest that TF expression in the coronary circulation after PTCA is a prognostic factor for late restenosis.

Cardiovascular surgery with cardiopulmonary bypass (CPB) induces activation of blood coagulation and systemic inflammation involved in post-operative complications. Our study evaluated the impact of the minimal extracorporeal circulation (mini-CPB) system (Synergy, Sorin Group) on these functional aspects. Twenty patients were randomly assigned to standard CPB (n = <em>1</em>0) or to Synergy (n = <em>1</em>0). Platelet expression of PAC-<em>1</em>, and monocyte/granulocyte-platelet conjugates were evaluated by flow cytometry. A leukocyte-platelet adhesion index was calculated after cell number normalization. ELISAs were performed to measure IL-6 and TNF-alpha, thrombin-antithrombin III complexes (TAT), <em>prothrombin</em> <em>fragments</em> (F<em>1</em>+<em>2</em>), beta-thromboglobulin (beta-TG) and sP-selectin (sCD6<em>2</em>P). Blood samples were drawn at the time of anesthesia (T<em>1</em>), at the end of CPB (T<em>2</em>), and at 4 (T3) and <em>2</em>4 hours (T4) after weaning from CPB. All patients were similar for clinical characteristics. When compared to standard CPB, the Synergy showed lower levels of the monocyte-platelet adhesion index at T<em>2</em> (0.0<em>2</em>3 +/- 0.005 vs 0.063 +/- 0.0<em>1</em>3, P = 0.009<em>2</em>) and T4 (0.03<em>1</em> +/- 0.003 vs 0.055 +/- 0.005, P = 0.00<em>1</em>7), TAT complexes at T<em>2</em> (<em>2</em>7.<em>1</em>75 +/- 5.967 vs 86.59<em>2</em> +/- 5.4<em>1</em>5, P = 0.0005) and T3 (<em>2</em>6.977 +/- <em>2</em>.468 vs 45.<em>1</em>46 +/- 4.365, P = 0.004<em>1</em>), F<em>1</em>+<em>2</em> <em>fragments</em> at T<em>2</em> (<em>2</em>.<em>2</em><em>2</em><em>2</em> +/- 0.<em>2</em><em>2</em>6 vs 4.<em>2</em>49 +/- 0.<em>2</em>9<em>2</em>, P = 0.0009), and sP-selectin at T3 (<em>1</em><em>1</em>5.<em>1</em>7 +/- <em>1</em>9.6<em>2</em>3 vs <em>1</em>69.554 +/- <em>1</em>9.709, P = 0.0703) and T4 (<em>1</em>08.54<em>2</em> +/- 6.4<em>2</em>9 vs <em>1</em>40.799 +/- <em>1</em>4.77<em>1</em>, P = 0.0833). In summary, the Synergy exhibited a lower post-operative activation of blood coagulation, together with a reduced interaction between circulating monocytes and platelets.

Disturbance of fibrinolysis is common in rheumatoid arthritis (RA), and it may be associated with the increased cardiovascular risk observed in this population. We aimed to assess coagulation derangement and investigate whether abnormalities are influenced by demographic, inflammatory or metabolic factors in patients with RA. Levels of tissue plasminogen activator (tPA), plasminogen activator inhibitor (PAI-<em>1</em>), fibrinogen, <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> (PF<em>1</em> + <em>2</em>), thrombomodulin (TM), protein C and Von Willebrand factor (vWF) were compared between <em>1</em>4<em>1</em> RA patients and 50 healthy hospital controls. Within RA, coagulation factors were assessed alongside several demographic, inflammation and metabolic indicators. RA patients had higher levels of coagulation factors than controls. After correction for age and sex, having RA predicted increased tPA (B = 0.<em>1</em>5, P < 0.00<em>1</em>), PAI-<em>1</em> (B = 0.<em>2</em><em>1</em>, P < 0.00<em>1</em>), fibrinogen (B = 0.86, P < 0.00<em>1</em>), PF<em>1</em> + <em>2</em> (B = 0.<em>2</em>0, P < 0.00<em>1</em>), and TM (B = 0.0<em>1</em>, P = 0.03) levels. CRP correlated positively with tPA (P < 0.05), fibrinogen (P < 0.00<em>1</em>), TM (P < 0.05), PF<em>1</em> + <em>2</em> (P < 0.00<em>1</em>) and vWF (P < 0.00<em>1</em>). Metabolic factors linked with coagulation factors were hypertriglyceridaemia (tPA, P < 0.05; PAI-<em>1</em>, P < 0.05; protein C, P < 0.05) and insulin resistance (tPA, P < 0.0<em>1</em>; PAI-<em>1</em>, P < 0.0<em>1</em>; vWF, P < 0.05). Imbalance of coagulation and fibrinolytic mechanisms is common in RA and associates with age, inflammation, and metabolic factors. Further studies may determine whether these abnormalities are the consequence of acute inflammation or markers of vascular dysfunction.

BACKGROUND

In contrast to other extracorporeal treatments no established regime exists for anticoagulation with low-molecular-weight heparin (LMWH) in plasmapheresis therapy. A study was conducted to investigate whether LMWH (dalteparin-Na) is suitable as an effective anticoagulant in plasmapheresis therapy.

METHODS

Eleven patients with autoimmune neurological diseases and the necessity for a plasmapheresis therapy were enrolled. A capillary membrane filter was used. A total of <em>2</em>000 mL of human plasma was isovolumetrically exchanged per plasmapheresis cycle. The anticoagulation was accomplished with a single bolus of LMWH (dalteparin) of 80 to 90 IU per kg of body weight. The system was visually monitored. Anti-factor (F)Xa activity, thrombin-antithrombin III complex (TAT), and <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> (F <em>1</em>+<em>2</em>) were determined at regular intervals. Samples were taken from the collected plasma pool to determine the loss of LMWH during the plasmapheresis procedure.

RESULTS

All plasmapheresis cycles with LMWH were successful without complications. Approximately 40 percent of the initially administered LMWH bolus was lost by the large porous filter during the plasmapheresis. The anti-FXa values were determined to be 0.5 IU per mL during the entire plasmapheresis. TAT values were elevated (TAT median, <em>1</em>4.3 microg/L). F <em>1</em>+<em>2</em> values measured before the filter cartridge remained within the normal range for the entire plasmapheresis cycle ((<em>1</em>.<em>2</em> nmol/L) and were increasingly elevated after the filter.

CONCLUSIONS

Our initial experiences with LMWH for anticoagulation in plasmapheresis indicate that a body weight adjusted dose of LMWH (dalteparin) is suitable for anticoagulation in plasmapheresis therapy. No complications were observed. The data are encouraging. Further investigations will show if and how the present anticoagulation regime could be further optimized.

Disseminated intravascular coagulation (DIC) constitutes a part of the multiple organ failure (MOF) syndrome seen with such disorders as trauma and sepsis. Early detection of increased coagulation and fibrinolytic activity is important. The dynamic changes in some markers for early detection of the activation of these cascade systems are presented in relation to two patients with brain trauma. The clinical status and the severity of the disease were assessed by an established scoring method (APACHE II). The coagulation activation was noted by the appearance of increased end products of the coagulation cascade, such as soluble fibrin, thrombin-antithrombin complex, and <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em>. Fibrinolytic activation and an increased secondary inhibition of fibrinolysis were detected by increased levels of D-dimer and plasminogen activator inhibitor-<em>1</em>. Leukocyte activation was indicated by a rise in elastase. The laboratory results normalized with clinical improvement. These new methods seem to detect DIC earlier than traditional methods and may also be of value for monitoring treatment.

Colistin electrostatically interacts with lipopolysaccharides (LPS). Pre-clinical studies demonstrated beneficial effects of colistin on LPS-induced coagulation and fibrinolysis. The objective of this trial was to investigate the effects of colistin during experimental endotoxaemia. In this randomised, double-blind, placebo-controlled, crossover trial <em>1</em>6 healthy volunteers received a <em>2</em> ng/kg LPS bolus after infusion of <em>2</em>.5 million IU colistin or placebo. Plasma levels of F<em>1</em>+<em>2</em> <em>prothrombin</em> <em>fragments</em>, thrombin-antithrombin complexes (TAT), von Willebrand factor antigen levels (vWF), E-selectin, plasmin-antiplasmin complexes (PAP), tissue-type plasminogen activator (t-PA) antigen and activity, plasminogen activator inhibitor-<em>1</em> (PAI-<em>1</em>) were measured. Infusion of colistin significantly reduced peak concentrations of PAP complexes by 70 %, t-PA antigen levels by 63 % and t-PA activity by 48 %, while PAI-<em>1</em> levels decreased numerically by 63 %. Two hours after the LPS bolus F<em>1</em>+<em>2</em> levels and TAT complexes were slightly reduced in the colistin period, but peak concentrations were similar in both periods. Colistin blunted the LPS induced four-fold increase in soluble E-Selectin levels by ~50 % and the two-fold increase in vWF antigen levels by ~70 %. The LPS-scavenging actions of colistin significantly reduce endothelial activation and fibrinolytic response in the human endotoxaemia model, while the activation of the coagulation system remains largely unaffected.

Women with diabetes mellitus have an increased risk of developing coronary heart disease which may be related at least partially to unfavourable changes in haemostasis. The effect of oestrogen replacement therapy on haemostasis has not been studied systematically in women with non-insulin-dependent diabetes mellitus (NIDDM) and therefore this study was performed for that purpose. Twenty-five postmenopausal women with NIDDM were treated with <em>2</em> mg of <em>1</em>7-beta-oestradiol orally for 3 months in a double-blind, crossover, placebo-controlled trial. During the last <em>1</em>6 days of active treatment, <em>1</em> mg of norethisterone acetate was added for <em>1</em>0 days for endometrial protection. Blood samples were taken at baseline and after 68 days of active or placebo treatment. Treatment with oestradiol was followed by a marked decrease in the activity of plasminogen activator inhibitor, compared with placebo. The activity of tissue plasminogen activator increased significantly. Levels of antithrombin decreased during treatment with oestradiol, whereas no changes were seen in levels of fibrinogen, von Willebrand factor, <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em>, protein S, protein C or resistance to activated protein C. In conclusion, oestrogen replacement therapy in postmenopausal women with NIDDM improved the fibrinolytic activity, while only clinically insignificant alterations in the clotting system were seen. These changes in haemostasis may have a favourable impact on the risk for coronary heart disease in diabetic women.

BACKGROUND

Activation of coagulation and fibrinolysis is common among patients undergoing cardiopulmonary bypass (CPB) surgery. Little is known, however, about the impact of myocardial ischemia and reperfusion on coagulation activation and fibrinolysis in this clinical setting.

METHODS

We determined the levels of coagulation activation and fibrinolysis markers (CAFM) in <em>1</em>9 patients with severe coronary heart disease (CHD) during CPB surgery. FXIIa, tissue factor (TF), FVIIa, tissue plasminogen activator/plasminogen activator inhibitor-<em>1</em> complexes (tPA/PAI-<em>1</em>), <em>prothrombin</em> <em>fragments</em> <em>1</em>+<em>2</em> (F<em>1</em>+<em>2</em>), D-dimers (DD) and plasmin-plasmin inhibitor complexes (PPI) were measured at baseline, prior to and after cardioplegic myocardial ischemia. Simultaneous blood samples were drawn from the aorta and the coronary sinus to evaluate arteriovenous CAFM plasma level gradients.

RESULTS

Myocardial ischemia induced significant increases in gradients of FXIIa and F<em>1</em>+<em>2</em> levels across the coronary circulation without influencing systemic levels of these markers significantly. Systemic levels of FXIIa, tPA/PAI-<em>1</em>, F<em>1</em>+<em>2</em>, DD and PPI increased significantly during CPB operation. There was a significant linear correlation between FXIIa, FVIIa, F<em>1</em>+<em>2</em>, DD and PPI.

CONCLUSIONS

Myocardial ischemia induces contact activation and thrombin generation rather than release of tPA and might thus contribute to postoperative thromboembolic complications. Surgery itself and CPB cause activation of coagulation and fibrinolysis as already described. A significant association between FXIIa, FVIIa, F<em>1</em>+<em>2</em>, DD and PPI suggests a relationship between contact activation, thrombin generation, fibrin formation and fibrinolysis.

BACKGROUND

Colon cancer (CC) is frequently complicated by thromboembolic episodes. Thrombin plays a role in angiogenesis and among others induces the synthesis of vascular endothelial growth factor (VEGF) and its receptors (VEGFR-<em>1</em> and VEGFR-<em>2</em>). The aim of this study was to assess the expression of <em>prothrombin</em> <em>fragment</em> F<em>1</em>+<em>2</em> (F<em>1</em>+<em>2</em>), a byproduct in thrombin generation (indicating the presence of thrombin), in relation to the presence of VEGFR-<em>2</em>-bound VEGF (VEGF:VEGFR-<em>2</em>), as an indicator of VEGFR-<em>2</em> activation in human CC tissue.

METHODS

Immunohistochemical ABC and double staining studies were performed using antibodies against F<em>1</em>+<em>2</em> and VEGF:VEGFR-<em>2</em> in 59 specimens obtained from CC patients.

RESULTS

Medium and high expression of both F<em>1</em>+<em>2</em> and VEGF:VEGF<em>2</em> in association with CC cells and endothelial cells was demonstrated. Moreover, coexpression of F<em>1</em>+<em>2</em> and VEGF:VEGFR-<em>2</em> was observed in the cells.

CONCLUSIONS

The results may suggest a possible functional interaction between thrombin and VEGF-R<em>2</em> stimulation in human CC in vivo.

BACKGROUND

The risk of thrombosis is clearly increased in the postpartum period. Mice with a targeted deletion of the transmembrane domain of tissue factor (TF) develop serious activation of blood coagulation and widespread thrombosis after delivery.

OBJECTIVE

We hypothesized that TF, abundantly present in placental tissue, is released during delivery, resulting in the activation of blood coagulation. We measured sensitive markers for TF-dependent activation of coagulation before and after induction of labor in two groups: a vaginal delivery (VAG) group and a cesarean section (CS) group.

RESULTS

One hour after delivery, soluble TF (sTF) significantly increased in both groups [VAG group (mean +/- SD) <em>2</em><em>2</em>6 +/- 4<em>2</em> to 380 +/- 4<em>2</em> pg mL(-<em>1</em>) and CS group <em>1</em>93 +/- <em>1</em>7 to 355 +/- 44 pg mL(-<em>1</em>)]. The day after delivery, sTF was somewhat less increased. Both groups also showed an increase in factor VIIa, indicating activation of the TF pathway of coagulation. Indeed, after delivery, TF-dependent coagulation, as measured by the TF clotting time assay, was significantly enhanced. Increased plasma levels of <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> and thrombin-antithrombin complexes demonstrated thrombin generation following delivery. TF pathway-dependent activation of coagulation upon delivery was not blocked by TF pathway inhibitor and was not dependent on the mode of delivery.

CONCLUSIONS

The postdelivery increase in TF-dependent activation of coagulation is likely to be a natural mechanism to prevent excessive blood loss during and after delivery, and may also indicate a novel mechanism by which puerperal women have an increased risk of venous thromboembolism.

The aim of this study was to compare fibrinolysis in normal pregnancy and pre-eclampsia using individual markers of thrombosis and fibrinolysis with the contribution of a new parameter, global fibrinolytic capacity. Coagulation was determined with thrombin-antithrombin complex and <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> (F <em>1</em>+<em>2</em>) and fibrinolysis markers. Tissue plasminogen activator, plasminogen activator inhibitor-<em>1</em> and global fibrinolytic capacity were determined in <em>1</em>4 normal pregnancies and <em>2</em>9 women with pre-eclampsia. global fibrinolytic capacity was also determined in <em>1</em>4 age-matched healthy women. The Mann-Whitney U test and Pearson correlation test were used for statistical analysis. Thrombin-antithrombin complex, <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> levels, and global fibrinolytic capacity levels in pre-eclamptic women were significantly higher than in women with normal pregnancies (P < 0.05). Tissue plasminogen activator, plasminogen activator inhibitor-<em>1</em> levels were also significantly higher in the pre-eclampsia group (P < 0.00<em>1</em> and P < 0.05 respectively). No significant correlation was found between global fibrinolytic capacity and thrombin-antithrombin complex, <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> levels, tissue plasminogen activator or plasminogen activator inhibitor-<em>1</em> activity. Our results suggest that both thrombin formation and fibrinolysis are increased in pre-eclampsia compared with normal pregnancy. The increased global fibrinolytic capacity indicates that fibrinolysis remains preserved in pre-eclampsia. We suggest that global fibrinolytic capacity may be a useful parameter for accurately measuring in-vivo fibrinolysis globally, instead of with single parameters which may overlook the complex interactions between coagulation and fibrinolytic systems.