BACKGROUND

Bacterial endotoxins can induce the synthesis and release of vascular endothelial growth factor (VEGF), which may alter vascular permeability and cause vascular leakage.

METHODS

The effect of acute systemic inflammation on VEGF concentration was measured in healthy males after an intravenous bolus infusion of Escherichia coli endotoxin (lipopolysaccharide, LPS, <em>2</em>0 IU kg-<em>1</em>) in a double-blind, placebo-controlled parallel group study. LPS administration was followed by an infusion of lepirudin (bolus 0.<em>1</em> mg kg-<em>1</em>, continuous infusion of 0.<em>1</em> mg kg-<em>1</em> h-<em>1</em>, n = <em>1</em><em>2</em>) or saline (n = <em>1</em><em>2</em>).

RESULTS

Plasma VEGF increased from a mean of <em>1</em>5.<em>1</em> pg mL-<em>1</em> to 74.6 pg mL-<em>1</em> 5 h after LPS (P < 0.003). Body temperature, pulse rate, leukcytes, <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> (F<em>1</em> + <em>2</em>) and lactoferrin increased and platelets decreased after LPS (P < 0.05). The LPS-induced increase in VEGF was paralleled by the neutrophil cell degranulation marker lactoferrin but not by F<em>1</em> + <em>2</em>, and was not affected by lepirudin, which blunted F<em>1</em> + <em>2</em> formation (P < 0.05).

CONCLUSIONS

Inflammation-induced activation of leukcytes rather than platelets plays a role in the marked increase in VEGF, which cannot be abrogated by antithrombotic therapy.

OBJECTIVE

Tissue factor (TF) plays a central role during disseminated intravascular coagulation (DIC) in sepsis. We hypothesized that a frequent D/I polymorphism, at nucleotide position -<em>1</em><em>2</em>08 in the promoter region, could influence TF-mRNA and downstream coagulation.

METHODS

Basal- and lipopolysaccharide (LPS)-induced TF-mRNA expression, microparticle-associated TF-procoagulant activity and coagulation were determined in healthy men (n = 74) before and after endotoxin (LPS) infusion (<em>2</em> ng kg(-<em>1</em>)). Basal values of TF-mRNA ranged between 34 and>> 37.5 cycles.

RESULTS

Baseline TF-mRNA levels significantly differed between genotypes: I/I carriers had almost <em>2</em>-fold higher TF-mRNA levels compared to D/D carriers at baseline (P < 0.0<em>1</em>). In accordance, higher levels of microparticle-associated TF-procoagulant activity could be seen in I/I carriers. However, the genotype did not affect basal or LPS-induced levels of prothrombin fragment F<em>1</em>+<em>2</em>, D-dimer or cytokines including tumor necrosis factor and interleukin-6.

CONCLUSIONS

The TF-<em>1</em><em>2</em>08 polymorphism is functional in that it regulates basal TF-mRNA in circulating monocytes and circulating microparticle-associated TF-procoagulant activity in vivo, but does not influence the relative increase in TF-mRNA or coagulation activation during low-grade endotoxemia.

BACKGROUND

The purpose of this study was to investigate plasma levels of thrombin activatable fibrinolysis inhibitor (TAFI) and TAFI's relationship with coagulation markers (<em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em>) in gastric cancer patients.

METHODS

Thirty-three patients with gastric adenocarcinoma and <em>2</em>9 healthy control subjects were prospectively enrolled in the study. Patients who had a history of secondary malignancy, thrombosis related disease, oral contraceptive use, diabetes mellitus, chronic renal failure or similar chronic metabolic disease were excluded from the study. A fasting blood sample was drawn from patients to determine the plasma levels of TAFI and Prothrombin Fragment <em>1</em> + <em>2</em> (F <em>1</em> + <em>2</em>). In addition, data on patient age, sex, body mass index (BMI) and stage of disease were recorded. The same parameters, except stage of disease, were also recorded for the control group. Subsequently, we assessed the difference in the levels of TAFI and F <em>1</em> + <em>2</em> between the patient and control groups. Moreover, we investigated the relation of TAFI and F <em>1</em> + <em>2</em> levels with age, sex, BMI and stage of disease in the gastric cancer group.

RESULTS

There were no statistical differences in any demographic variables (age, gender and BMI) between the groups (Table <em>1</em>). The mean plasma TAFI levels of the gastric cancer group (69.4 ± 33.<em>1</em>) and control group (73.3 ± <em>2</em>7.5) were statistically similar (P = 0.6<em>2</em>). The mean plasma F <em>1</em> + <em>2</em> level in the gastric cancer group was significantly higher than for those in the control group (549.7 ± 3<em>2</em>5.3 vs <em>1</em>5<em>1</em>.9 ± 67.<em>1</em>, respectively; P < 0.00<em>1</em>). In the gastric cancer group, none of the demographic variables (age, gender and BMI) were correlated with either TAFI or F <em>1</em> + <em>2</em> levels. Also, no significant associations were found between the stage of the cancer and either TAFI or F <em>1</em> + <em>2</em> levels.

CONCLUSIONS

In our study, TAFI levels of gastric cancer patients were similar to healthy subjects. The results of our study suggest that TAFI does not play a role in pathogenesis of the hypercoagulable state in gastric cancer patients.

Malignancy frequently is accompanied by activated coagulation and fibrinolysis indicating a hypercoagulable state. The purpose of our study was to estimate the contribution of local tumor-induced mechanisms to the activation of hemostasis and fibrinolysis. In a prospective study, we compared the plasma levels of thrombin-antithrombin complexes, <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em>, and D-dimers in blood samples that simultaneously were drawn from the superior vena cava and the pulmonary vein of a tumor-bearing pulmonary lobe. Samples from the superior vena cava were drawn before operation and served as controls. After thoracotomy, a second group of samples was simultaneously taken from the pulmonary veins of the tumor-bearing lobe and the superior vena cava. Forty-five patients with pulmonary malignancies were included (<em>2</em>5 adenocarcinomas and <em>2</em>0 squamous cell carcinomas). There were no significant differences of thrombin-antithrombin complexes, <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em>, and D-dimers levels in patients suffering from adenocarcinoma and from squamous cell carcinoma. Intraoperatively, <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> and D-dimers levels were markedly increased when compared with the preoperative values (p<0.000<em>1</em>). There was no increase of thrombin-antithrombin complexes levels due to the operative traumatization. <em>Prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em>, thrombin-antithrombin complexes, and D-dimers plasma levels were significantly higher in the pulmonary venous blood than in the blood simultaneously drawn from the superior vena cava (p<0.000<em>1</em>). Our findings indicate that malignant lung tumors directly contribute to the activation of hemostasis and fibrinolysis in these clinical settings.

We recently observed that the prophylactic administration of high doses of OKT3 monoclonal antibody (MoAb) in cadaveric renal transplantation favors the development of thromboses of the grafts' main vessels and of thrombotic microangiopathies. These clinical observations led us to perform sequential determinations of plasma levels of <em>prothrombin</em> <em>fragment</em> <em>1</em> and <em>2</em> (F <em>1</em> + <em>2</em>) and fibrin degradation products (FDP) after the first injection of 5 or <em>1</em>0 mg OKT3 given as prophylaxis in kidney transplant recipients. The values observed have been compared with those of kidney transplant recipients not treated with OKT3. F <em>1</em> + <em>2</em> levels peaked four hours after the first injection of 5 mg OKT3 (mean +/- SEM: 4.8<em>2</em> +/- 0.73 vs. <em>1</em>.75 +/- 0.37 nmol/liter in controls, P < 0.0<em>1</em>), indicating activation of the common pathway of the coagulation cascade. FDP levels were already above baseline values at four hours and continued to increase until <em>2</em>4 hours (mean +/- SEM at <em>2</em>4 hr, 47<em>2</em>9 +/- 879 vs. <em>1</em>038 +/- 3<em>2</em>0 ng/ml in controls, P < 0.05), indicating a fibrinolytic process. The magnitude and the time course of the changes in F <em>1</em> + <em>2</em> and FDP plasma levels were similar whether the patients received 5 or <em>1</em>0 mg dose of OKT3. The levels of von Willebrand factor (VWF) antigen, a molecule released by activated or damaged endothelial cells, were also significantly increased after injection of OKT3 (mean +/- SEM at <em>2</em>4 hr, 3.67 +/- 0.<em>1</em>8 vs. <em>2</em>.<em>1</em>7 +/- 0.<em>1</em><em>1</em> U/ml in controls, P < 0.05). The procoagulant effects of OKT3 were further investigated in vitro on human umbilical vein endothelial cells (HUVEC).(ABSTRACT TRUNCATED AT <em>2</em>50 WORDS)

<em>Prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> (F<em>1</em>+<em>2</em>), which comes from in vivo cleavage of <em>prothrombin</em> by factor Xa, is considered to be useful for diagnosis of thrombosis. Recognition of the central role of thrombosis in the pathogenesis ofcardiovascular disease has prompted growing interest in the association o F<em>1</em>+<em>2</em> with cardiovascular clinical syndromes. Increased F<em>1</em>+<em>2</em> levels have reported in venous thromboembolism, inflammation, cancer, sepsis, acute coronary syndromes, stroke, peripheral arterial disease, atrial fibrillation and during the postoperative period. However, a clear relationship with the appearance of thrombosis has not always been consistently demonstrated. Besides its potential prognostic and diagnostic value, it could also be usefu in assessing the impact of various therapies. However, it should be kept in mind that measurement of hemostasis activation markers has several important biological and methodological disadvantages. Activation markers reflect the presence of thrombosis in any vascular bed, so they are not specific. Furthermore, elevations occur not only in the presence of overt thrombosis but also during the hypercoagulable state. The cutoff level to be used for the definition of elevations is still largely unknown due to the use of different analytical methods, none of which have been standardized until know. Finally, the prognostic value of F<em>1</em>+<em>2</em> and other markers of coagulation activation remains to be fully defined in future studies.

Co-crystallographic studies have shown that the interaction of human <em>prothrombin</em> <em>fragment</em> <em>2</em> (F<em>2</em>) with thrombin involves the formation of salt bridges between the kringle inner loop of F<em>2</em> and anion-binding exosite II of thrombin. When F<em>2</em> binds to thrombin, it has been shown to evoke conformational changes at the active site and at exosite I of the enzyme. Using plasma, recombinant, and synthetic F<em>2</em> peptides (F<em>2</em>, rF<em>2</em>, and sF<em>2</em>, respectively) we have further localized the thrombin-binding domain on F<em>2</em>. F<em>2</em>, rF<em>2</em>-(<em>1</em>-<em>1</em><em>1</em>6), rF<em>2</em>-(55-<em>1</em><em>1</em>6), and sF<em>2</em>-(63-<em>1</em><em>1</em>6), all of which contain the kringle inner loop (residues 64-93) and the acidic COOH-terminal connecting peptide (residues 94-<em>1</em><em>1</em>6), bind to thrombin-agarose. In contrast, analogues of the kringle inner loop, sF<em>2</em>-(63-90), or the COOH-terminal connecting peptide, sF<em>2</em>-(9<em>2</em>-<em>1</em><em>1</em>6), do not bind. Thus, contrary to predictions from the crystal structure, the COOH-terminal connecting peptide as well as the kringle inner loop are involved in the interaction of F<em>2</em> with thrombin. F<em>2</em> and sF<em>2</em>-(63-<em>1</em><em>1</em>6) bind saturably to fluorescently labeled active site-blocked thrombin with Kd values of 4.<em>1</em> and 5<em>1</em>.3 microM, respectively. The affinity of sF<em>2</em>-(63-<em>1</em><em>1</em>6) for thrombin increases about 5-fold (Kd = <em>1</em>0 microM) when Val at position 78 is substituted with Glu. F<em>2</em> and sF<em>2</em>-(63-<em>1</em><em>1</em>6) bind to exosite II on thrombin because both reduce the heparin-catalyzed rate of thrombin inhibition by antithrombin approximately 4-fold. In contrast, only F<em>2</em> slows the uncatalyzed rate of thrombin inactivation by antithrombin. Like F<em>2</em>, sF<em>2</em>-(63-<em>1</em><em>1</em>6) induces allosteric changes in the active site and exosite I of thrombin because it alters the rates of thrombin-mediated hydrolysis of chromogenic substrates and displaces fluorescently labeled hirudin54-65 from active site-blocked thrombin, respectively. Both peptides also prolong the thrombin clotting time of fibrinogen in a concentration-dependent fashion, reflecting their effects on the active site and/or exosite I. These studies provide further insight into the regions of F<em>2</em> that evoke functional changes in thrombin.

We studied the effects of bypass circuit surface heparinization on kallikrein-kinin, coagulation, fibrinolytic and complement activation in a closed model system for simulating veno-venous bypass (WBP) in orthotopic liver transplantation (OLT). The circuits were identical to those in routine use during clinical OLT in our institution. Fresh whole human blood diluted <em>1</em>:<em>2</em> with Ringer's acetate was circulated at a non-pulsatile flow (<em>2</em> l/min) and at a constant temperature (37.5 degrees C) for <em>1</em><em>2</em> h. In <em>1</em>0 experiments, the entire inner surface of the circuits was coated with end-point attached heparin (HC). In the remaining <em>1</em>0, non-treated PVC tubing was used (NC). Components of the plasma kallikrein-kinin, coagulation, fibrinolytic and complement systems were analyzed using functional techniques (chromogenic peptide substrate assays) and enzyme immunoassays at baseline, 3 and <em>1</em><em>2</em> h. Significant activation of the initial (C3bc) and terminal (TCC) components of the complement system were found in both the NC and HC groups after 3 and <em>1</em><em>2</em> h: C3bc: NC: baseline = 4 (3.5-7.7), 3 h = <em>1</em>7.3* (<em>1</em><em>2</em>.5-<em>2</em>7), <em>1</em><em>2</em>h = 3<em>1</em>* (<em>1</em>7.7-63.6), HC: baseline = 4.9 (3.<em>2</em>-6.8), 3h = 9* (6-<em>1</em>4.4), <em>1</em><em>2</em>h = <em>1</em>3.7* (7.4-<em>1</em>8.<em>1</em>). TCC: NC: baseline = 0.4 (0.<em>2</em>-0.6), 3h = 5*(0.8-<em>1</em><em>1</em>.9), <em>1</em><em>2</em> h: <em>1</em>3.<em>1</em>* (4.<em>2</em>-<em>2</em>5.7). HC: baseline = 0.5 (0.<em>1</em>-0.6), 3 h = 0.6* (0.<em>1</em>-0.8), <em>1</em><em>2</em> h = <em>1</em>.<em>2</em>* (0.3-<em>2</em>) AU/ml; median and range (*: p < 0.05). The C3bc and TCC concentrations were significantly higher in the NC group at 3 and <em>1</em><em>2</em> h, compared to the HC group: C3bc (NC vs. HC group): 3 h, p < 0.00<em>1</em>; <em>1</em><em>2</em> h, p < 0.00<em>1</em>. TCC (NC vs. HC group): 3h, p < 0.00<em>1</em>; <em>1</em><em>2</em> h, p < 0.00<em>1</em>. Significant increases in the values of thrombin-antithrombin complexes (p = 0.003), <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> (p = 0.006) and plasmin-alpha<em>2</em>-antiplasmin complexes (p = 0.0<em>1</em>6) were found in the non-coated group, but not in the heparin-coated group during the observation period, showing that the coagulation and fibrinolytic systems were activated in the non-coated circuits. We conclude that heparin-coating of the internal surface of the extracorporeal perfusion circuit used for WBP reduces activation of the plasma cascade systems in a closed venous system in vitro.

BACKGROUND

Antagonists of the platelet glycoprotein IIb/IIIa decrease acute ischemic complications after percutaneous coronary interventions (PCI). Abciximab (c7E3 Fab, ReoPro) has been reported to decrease thrombin generation in vitro. We investigated in vivo the effect of abciximab therapy on thrombin generation, thrombin activity, and the activated clotting time (ACT) during PCI.

METHODS

We studied 3<em>2</em> consecutive patients who underwent PCI for unstable coronary syndromes. Group I (n = 11) was treated with heparin plus aspirin, and group II (n = <em>2</em>1) was treated with heparin plus aspirin plus standard-dose abciximab, administered 5 minutes after the initial heparin bolus. Patients received a standardized heparin bolus at time 0, and arterial blood specimens for <em>prothrombin</em> <em>fragment</em> F1.<em>2</em>, fibrinopeptide A (FPA), and ACT were obtained from the guiding catheter at 5 minutes, 10 minutes (ACT only), <em>2</em>0 minutes, and at the end of the PCI. Standard-dose abciximab was administered in group II only. Each patient served as his or her own control, and the changes against the baseline were compared between the <em>2</em> groups.

RESULTS

There were no significant differences between the <em>2</em> groups regarding baseline characteristics, hematocrit, and platelet count. Group I patients had higher ACT and lower F1.<em>2</em> and FPA compared with group II at baseline. Subsequent measurements demonstrated a gradual decrease in FPA and F1.<em>2</em> in group II; the end of procedure versus baseline changes that occurred in F1.<em>2</em> were significantly different compared with group I (decrease of 0.59 +/- 0.<em>2</em><em>2</em> nmol/L in group II vs increase of 0.<em>2</em><em>2</em> +/- 0.3 nmol/L in group I, P =.04), and a trend in the same direction was evident for FPA changes (decrease of 1.46 +/- 1.16 ng/mL in group II vs increase of <em>2</em>.<em>2</em>5 +/- 1.58 ng/mL in group I, P =.07). The ACT response to abciximab was variable, but a 6.3% increase (+<em>2</em>0 sec) in ACT was documented 5 minutes after abciximab bolus in group II compared with the 3.4% decrease (-10 sec) observed in group I at the same time point (P =.1).

CONCLUSIONS

Addition of abciximab to heparin plus aspirin during PCI was associated with a significant decrease in thrombin generation and a borderline decrease in thrombin activity.

The present study was designed to compare the biocompatibility of three cardiopulmonary bypass setups with different surface coatings, and to determine if coating of the whole circuit with one of the coatings was more beneficial than coating of the oxygenator only. Extracorporeal devices entirely coated with synthetic polymers (Avecor, n = 6) were compared to oxygenators coated with synthetic polymers (Avecor, n = 6), end-point, covalently attached heparin (CBAS, n = 6) or absorbed heparin (Duraflo <em>2</em>, n = 6) in an in vitro model of a heart lung machine. The circuits were primed with fresh human whole blood and Ringer's acetate and recirculated at 4 l/min at 30 degrees C for <em>2</em> h. Test samples were obtained at regular intervals and analysed for myeloperoxidase (MPO), platelet counts, beta-thromboglobulin, heparin, <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em>, plasmin anti-plasmin complexes, and complement activation products. The mean MPO concentrations increased in the Avecor-coated oxygenator group (AV) from <em>2</em>47 at the start to 67<em>1</em> microg/l at the termination of the experiments, in the Avecor-coated total circuit group (AV-T) from <em>1</em><em>1</em>6 to <em>2</em>88 microg/l, in the Duraflo <em>2</em> coated oxygenator group (DU) from <em>1</em>60 to 33<em>2</em> microg/l, and in the CBAS-coated oxygenator (CA) group from <em>1</em>7<em>2</em> to 3<em>1</em><em>1</em> microg/l. The MPO concentrations increased significantly in all groups (p < 0.03). The increase in group A was significantly higher than in the other three groups (p = 0.007). The mean platelet counts decreased in the Avecor-coated total circuit group from <em>1</em><em>1</em>7 at start to 99 x <em>1</em>0(9)/l at termination of the experiments, in the Avecor-coated oxygenator group from <em>1</em><em>1</em>9 to <em>1</em>03 x <em>1</em>0(9)/l, in the Duraflo <em>2</em> group from 96 to 86 x <em>1</em>0(9)/l, and in the CBAS group from <em>1</em>3<em>2</em> to <em>1</em><em>2</em>3 x <em>1</em>0(9)/l. The platelet counts decreased significantly in all groups (p < 0.0<em>1</em>), but the intergroup differences were not significant (p = 0.<em>1</em>5). The mean beta-thromboglobulin concentrations increased in the Avecor-coated total circuit group from <em>1</em>93 at the start to 754 ng/ml at the termination of the experiments, in the Avecor-coated oxygenator group from 474 to <em>1</em>654 ng/l, in the Duraflo <em>2</em> group from 496 to <em>1</em><em>2</em>80 ng/l, and in the CBAS group from 4<em>1</em>8 to 747 ng/l. The beta-thromboglobulin increase was significant in each group (p < 0.0<em>1</em>), but not between the groups (p = 0.49). The mean heparin concentrations in the Duraflo <em>2</em> group increased from <em>2</em>460 at the start to <em>2</em>897 IU/l at termination of the experiments, in the CBAS group from <em>2</em>468 to <em>2</em>5<em>1</em>8 IU/l. In the Avecor-coated oxygenator group heparin concentrations decreased from <em>2</em>0<em>1</em>0 to <em>1</em>968 IU/l, and in the Avecor-coated total circuit group from <em>2</em>00<em>2</em> to <em>1</em>9<em>2</em>7 IU/l. The differences in heparin concentrations were significant between the Duraflo <em>2</em> group and the other groups (p < 0.05). The mean <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> concentrations increased in the CBAS group from 0.4 at the start to <em>2</em>.<em>1</em> nmol/l at the end of the experiments, in the Avecor-coated oxygenator group from 0.4 to 0.6 nmol/l, in the Avecor-coated total circuit group from 0.3 to 0.4 nmol/l, and in the Duraflo <em>2</em> group from <em>1</em>.<em>2</em> to <em>1</em>.3 nmol/l. The <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> increase was significant in all groups (p < 0.05), but there were no significant intergroup differences (p = 0.54). There were no significant differences at the termination of the experiments among the four groups regarding complement activation as measured by C3 activation products and the terminal complement complex. In the present in vitro model of a heart-lung machine, none of the three specific setups with different coatings was superior with regard to all test parameters. The CBAS group generated the highest levels of <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> formation, but least complement activation. The increasing plasma heparin concentrations in the Duraflo <em>2</em> group indicated more unstable heparin bonding. The Avecor-coated total circuit group were superior to the Avecor-coated oxygenator group regarding plasma concentrations of MPO, but not compa

The conversion of the blood coagulation zymogen <em>prothrombin</em> to thrombin is associated with the production of several cleavage intermediates and products. In contrast to earlier studies of <em>prothrombin</em> cleavage in chemically defined systems, the current investigation examines the <em>fragment</em>ation of human <em>prothrombin</em> in normal plasma. Radiolabeled <em>prothrombin</em> was added to platelet-poor relipidated normal human plasma, and clotting was initiated with the addition of Ca(II) and kaolin. Analysis of the radiolabeled <em>prothrombin</em> cleavage products by polyacrylamide gel electrophoresis in the presence of dodecyl sulfate and beta-mercaptoethanol identified a heretofore unobserved product of <em>prothrombin</em> activation with an apparent molecular weight of 45,000. This product was identified as <em>fragment</em> <em>1</em> X <em>2</em> X 3, the NH<em>2</em>-terminal <em>2</em>86 amino acids of <em>prothrombin</em>. The product was isolated from a <em>prothrombin</em> digest by immunoaffinity chromatography using anti-<em>prothrombin</em>:Ca(II) antibodies and by preparative gel electrophoresis. Its amino-terminal sequence is identical to that of <em>prothrombin</em>. Digestion of this product with either Factor Xa or thrombin yields, at a minimum, <em>fragment</em> <em>1</em> X <em>2</em> and <em>fragment</em> <em>1</em>. Amino-terminal sequence analysis of the products obtained by digestion with Factor Xa of the unknown activation product indicated 3 amino acid residues at each cycle consistent with the presence of <em>fragment</em> <em>1</em>, <em>fragment</em> <em>2</em>, and <em>fragment</em> 3. To unambiguously identify the COOH-terminal amino acid sequence of the product, its factor Xa digestion products were separated by reverse-phase high performance liquid chromatography. Edman degradation of one peptide revealed the complete sequence of <em>fragment</em> 3. On this basis, we identify the Mr 45,000 polypeptide as <em>fragment</em> <em>1</em> X <em>2</em> X 3 and indicate that it is a prominent product of <em>prothrombin</em> conversion to thrombin when activation occurs in plasma.

The biological activity of thrombin and coagulation factor Xa was assessed in 6<em>2</em> insulin-dependent diabetic patients. A group of non-diabetic subjects of comparable age and urinary albumin excretion rate (< 30 mg/<em>2</em>4 h) served as control subjects (group <em>1</em>, n = <em>1</em>4). The patients were divided into three groups according to urinary albumin excretion rate. In group <em>2</em>, albumin excretion rate was less than 30 mg/<em>2</em>4 h (n = <em>1</em>7), in group 3 albumin excretion rate was in the range 30-300 mg/<em>2</em>4 h (n = <em>2</em>0) and in group 4 albumin excretion rate was greater than 300 mg/<em>2</em>4 h (n = <em>2</em>5). Compared to non-diabetic control subjects an increase in the biological activity of factor Xa was observed in all groups of diabetic patients (<em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> levels were <em>1</em>.<em>1</em>4 +/- 0.38 nmol/l in group <em>2</em>, p < 0.005; <em>1</em>.06 +/- 0.45 nmol/l in group 3, p < 0.05 and <em>1</em>.03 +/- 0.3<em>1</em> nmol/l in group 4, p < 0.05 vs 0.75 +/- 0.34 nmol/l in group <em>1</em>). No difference in the level of antithrombin III was seen between the groups. We reconfirmed the presence of intimal dysfunction in diabetic nephropathy demonstrated by elevated transcapillary escape rate of albumin in group 4 compared with group <em>2</em> (8.9 +/- <em>2</em>.0% vs 7.0 +/- <em>1</em>.9%, p < 0.05). An overall positive correlation between transcapillary escape rate and <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> was found (r = 0.36, p < 0.005).(ABSTRACT TRUNCATED AT <em>2</em>50 WORDS)

NO is a potent inhibitor of in vitro platelet aggregation and adhesion. In view of possible future widespread use of NO in pulmonary and cardiovascular diseases, we investigated the role of NO in hemostatic system activation in vivo in humans. Sixteen healthy male volunteers (age range, <em>2</em><em>2</em> to 33 years) received either NO by inhalation (50 ppm over 30 minutes; n = 8) or the NO synthase inhibitor NG-monomethyl L-arginine (L-NMMA 3mg/kg body weight i.v. over 5 minutes; n = 8), beta-Thromboglobulin (beta-TG), an indicator of platelet activity; <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em> (F <em>1</em> + <em>2</em>), an index of coagulation activation; and thromboxane B<em>2</em> (TxB<em>2</em>), a measure of platelet prostaglandin synthesis, were determined in blood samples obtained from bleeding-time incisions ("shed blood") at baseline and after administration of the respective drug. In addition, beta-TG and F <em>1</em> + <em>2</em> were also determined in venous blood. To verify the systemic effects of the drugs, methemoglobin and plasma nitrites/nitrates were measured in the NO group, and cardiac output and exhaled NO were measured in the L-NMMA group. Compared with baseline, methemoglobin and plasma nitrates increased by 73 +/- <em>1</em><em>2</em>% (P= .006) and 60 +/- 9% (P< .00<em>1</em>), respectively, following NO inhalation. L-NMMA infusion resulted in decreases in both cardiac output by <em>1</em>6 +/- <em>2</em>%; P< .00<em>1</em>) and exhaled NO (by 54 +/- 7%; P< .00<em>1</em>). NO inhalation or L-NMMA infusion had no significant effect on beta-TG, F <em>1</em> + <em>2</em>, and TxB<em>2</em> levels in shed blood.(ABSTRACT TRUNCATED AT <em>2</em>50 WORDS)

Cardiac surgery involving cardiopulmonary bypass (CPB) leads to activation of the hemostatic/inflammatory system. We compared the influence of a half-dose aprotinin regimen on postoperative blood loss and the activation of the hemostatic/inflammatory system during CPB, when used during a heparin-level-based heparin management for cardiac surgery. Two-hundred patients (n = <em>1</em>00 in each group) were enrolled in this randomized prospective study. In Group I only heparin was given according to the results of the Hepcon HMS Plus. In Group II aprotinin was added with a bolus of <em>1</em> x <em>1</em>0(6) kallikrein inhibiting units (KIU) for the patient immediately before initiation of CPB, <em>1</em> x <em>1</em>0(6) KIU in the priming solution of the CPB, and a continuous infusion of <em>2</em>50,000 KIU/h during CPB. Postoperative blood loss was determined after <em>1</em><em>2</em> h. Heparin and antithrombin activity were evaluated by an anti-Xa assay and measurement of antithrombin III activity. Hemostatic activation was evaluated by adenosine diphosphate-stimulated platelet aggregometry and by measurements of the generation/release of beta-thromboglobulin (beta-TG), soluble P-selectin (sPS), thrombin (TAT), <em>prothrombin</em> <em>1</em> and <em>2</em> <em>fragments</em> (PTF<em>1</em>+<em>2</em>), factor XIIa (FXIIa), plasmin (PAP), and D-dimers. Inflammatory response was evaluated by measuring complement factors 5b-9 (C5b-9), interleukin (IL)-6, and neutrophil elastase (NE). There were no differences in the pre-CPB values or duration of CPB between the two groups. There were no differences in the post-CPB values for platelet count, platelet aggregation, beta-TG, sPS, TAT, PTF<em>1</em>+<em>2</em>, C5b-9, NE, or IL-6. The additional use of aprotinin resulted in a significant decrease of PAP, D-dimers, and <em>1</em><em>2</em> h postoperative blood loss, whereas generation of the contact factor XIIa was increased. The administration of aprotinin significantly reduced postoperative blood loss after cardiac surgery and CPB. This most likely has to be attributed to the antifibrinolytic effects of aprotinin. No effects on thrombin generation, platelet activation, inflammatory response, or clinical outcome were noted.

CONCLUSIONS

The use of half-dose aprotinin and heparin-level-based anticoagulation management during cardiopulmonary bypass leads to a significant reduction of postoperative blood loss after cardiac surgery. This effect can most likely be attributed to the antifibrinolytic effects of aprotinin, as we did not observe effects on other variables of activation of the hemostatic/inflammatory system.

Varying degrees of renal injury could lead to different changes in urinary protein composition. We want to find urinary candidate peptide biomarkers in type <em>2</em> diabetic patients with different extents of kidney injury. Two sets of patients were recruited. Discovery set: weak cationic-exchange magnetic beads coupled with matrix-assisted laser desorption ionization time-of-flight mass spectrometry were used to profile the low-molecular weight peptidome in urine samples from type <em>2</em> diabetes patients with normoalbuminura and microalbuminuria. The differently expressed urinary peptides were screened by ClinProTools<em>2</em>.<em>1</em> bioinformatics software and identified through nano-liquid chromatography-tandem mass spectrometry. Verification set: the above screened urinary peptides were validated by use matrix-assisted laser desorption ionization time-of-flight mass spectrometry on another group of type <em>2</em> diabetes patients with different extents use of kidney injury. In the screening and identification stages, seven urinary peptides were selected as the most promising biomarker candidates, and they were identified as <em>fragments</em> of vitronectin precursor, isoform <em>1</em> of fibrinogen alpha chain precursor, <em>prothrombin</em> precursor and inter-alpha-trypsin inhibitor heavy chain H4. The diagnostic efficacy of these urinary peptides was evaluated by area under the receiver operating characteristic curve, and they were 0.767, 0.768, 0.868, 0.9<em>1</em>0, 0.860, 0.843, and 0.865, respectively. In the verification stage, m/z <em>1</em>743.9, <em>2</em><em>1</em>54, <em>2</em><em>1</em>75.5, and <em>2</em><em>1</em>84.9 were decreased as albumin-to-creatinine (Alb/Cre) increased and m/z <em>2</em><em>2</em>3<em>1</em>.<em>1</em>, <em>2</em>430.8, and <em>2</em>756.<em>1</em> were elevated as Alb/Cre rose. These small molecule peptides are related to type <em>2</em> diabetes kidney damage, and they may play an important role in monitoring type <em>2</em> diabetes.

The effect of <em>prothrombin</em> <em>fragment</em> <em>2</em> on the inhibition of thrombin by antithrombin III has been studied. <em>Fragment</em> <em>2</em> was found to slow the rate of inhibition of thrombin by antithrombin III about 3-fold. The effect of <em>prothrombin</em> <em>fragment</em> <em>2</em> on antithrombin III inhibition was examined by comparing its action in the presence of either thrombin or meizothrombin (des <em>fragment</em> <em>1</em>). The second order rate constants for antithrombin III inhibition of thrombin with saturating <em>fragment</em> <em>2</em> and antithrombin III inhibition of meizothrombin (des <em>fragment</em> <em>1</em>) were the same. <em>Prothrombin</em> <em>fragment</em> <em>2</em> had no effect on either antithrombin III inhibition of meizothrombin (des <em>fragment</em> <em>1</em>) or Factor Xa. The effect of the <em>fragment</em> on the reaction mechanism of thrombin inhibition was evaluated to see if the <em>fragment</em> altered binding of antithrombin III to thrombin or inhibited the formation of the covalent complex. The <em>fragment</em> was found to have no inhibitory effect on the rate of covalent complex formation, indicating that the protective effect of the <em>fragment</em> is by inhibiting binding of antithrombin III to thrombin. These data suggest that <em>prothrombin</em> <em>fragment</em> <em>2</em> may be an important factor in controlling the localization of clot formation by regulating the interaction between thrombin and antithrombin III.

Perioperative hemorrhage is one of the principal causes of death in patients with ruptured abdominal aortic aneurysm (AAA). This study examines perioperative coagulation and fibrinolysis in patients undergoing ruptured AAA repair complicated by coagulopathy. Eight patients (8 men of median age 74, range 69-87, years) who developed clinical and laboratory evidence of coagulopathy during attempted repair of ruptured infrarenal AAA were prospectively studied. Platelet count, fibrinogen, clotting times, <em>prothrombin</em> <em>fragment</em> (PF) <em>1</em>+<em>2</em>, and tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) activities were measured preoperatively, immediately before, and 5 min and <em>2</em>4 hr after aortic declamping. Six patients died, three intraoperatively, one within <em>2</em>4 hr, and two in the late postoperative period. All patients had thrombocytopenia and prolonged clotting times intraoperatively with evidence of increased thrombin generation (as demonstrated by elevated PF <em>1</em>+<em>2</em>). Five patients had increased systemic fibrinolysis (as demonstrated by elevated t-PA activity) preoperatively and/or before aortic declamping and all of these patients died. Three patients had perioperative inhibition of systemic fibrinolysis (as demonstrated by elevated PAI activity) and two survived. These data demonstrate that coagulopathy in ruptured AAA repair may be associated with a hyperfibrinolytic state. Further research is required to determine if (a) a causal relationship exists between hyperfibrinolysis and coagulopathy and (b) whether antifibrinolytic agents can improve outcome if targeted at this group of patients.

The soybean is rich in isoflavone phytoestrogens, which are ligands for estrogen receptors, but it is unknown whether soy/phytoestrogens have similar procoagulant effects to estrogen. In this randomized double-blind trial, 40 healthy postmenopausal women of age 50-75 yr received soy protein isolate (40 g soy protein, <em>1</em><em>1</em>8 mg isoflavones) (n = <em>1</em>9) or casein placebo (n = <em>2</em><em>1</em>). Plasma markers of coagulation, fibrinolysis, and endothelial dysfunction were measured at baseline and 3 months. The baseline characteristics of the two groups were similar. Compared with casein placebo, soy decreased triglycerides (P < 0.005) and low-density lipoprotein/high-density lipoprotein ratio (P < 0.00<em>1</em>) and increased lipoprotein (a) (P < 0.05). Activity of coagulation factor VII (VIIc) decreased similarly in both groups (P < 0.005). <em>Prothrombin</em> <em>fragments</em> <em>1</em> + <em>2</em> (a marker of thrombin generation) decreased in the soy group (P < 0.005), but the change was not different from the casein group. There was no effect of soy on soluble fibrin (a marker of fibrin production), plasminogen activator inhibitor-<em>1</em> (a marker of fibrinolytic inhibitory potential), D-dimer (a marker of fibrin turnover), or von Willebrand factor (a marker of endothelial damage). In conclusion, the results of the current study do not support biologically significant estrogenic effects of soy/phytoestrogens on coagulation, fibrinolysis, or endothelial function.

Denaturation profiles of bovine <em>prothrombin</em> and its isolated <em>fragments</em> were examined in the presence of Na<em>2</em>EDTA, 5 mM CaCl<em>2</em>, and CaCl<em>2</em> plus membranes containing <em>1</em>-palmitoyl-<em>2</em>-oleoyl-3-sn-phosphatidylcholine (POPC) in combination with bovine brain phosphatidylserine (PS). We have shown previously [Lentz, B. R., Wu, J. R., Sorrentino, A. M., & Carleton, J. A. (<em>1</em>99<em>1</em>) Biophys. J. 60, 70] that binding to PS/POPC (<em>2</em>5/75) large unilamellar vesicles resulted in an enthalpy loss in the main endotherm of <em>prothrombin</em> denaturation (Tm approximately 57-58 degrees C) and a comparable enthalpy gain in a minor endotherm (Tm approximately 59 degrees C) accompanying an upward shift in peak temperature (Tm approximately 73 degrees C). This minor endotherm was also responsive to Ca<em>2</em>+ binding and, in the absence of PS/POPC membranes, corresponded to melting of the N-terminal, Ca<em>2</em>+ and membrane binding domain (<em>fragment</em> <em>1</em>). Peak deconvolution analysis of the <em>prothrombin</em> denaturation profile and extensive studies of the denaturation of isolated <em>prothrombin</em> domains in the presence and absence of PS/POPC vesicles suggested that membrane binding induced changes in the C-terminal catalytic domain of <em>prothrombin</em> (prethrombin <em>2</em>) and in a domain that links <em>fragment</em> <em>1</em> with the catalytic domain (<em>fragment</em> <em>2</em>). Specifically, the results have confirmed that the <em>fragment</em> <em>2</em> domain interacts with the stabilizes the prethrombin <em>2</em> domain and also have shown that <em>fragment</em> <em>2</em> interacts directly with the membrane. In addition, the results have demonstrated a heretofore unrecognized interaction between the catalytic and membrane binding domains. This interaction can account for another portion of the denaturation enthalpy that appears at high temperatures in the presence of membranes.(ABSTRACT TRUNCATED AT <em>2</em>50 WORDS)

BACKGROUND

Inflammation and coagulation are two intimately cross-linked defense mechanisms of most, if not all organisms to injuries. During cardiopulmonary bypass (CPB), these two processes are activated and interact with each other through several common pathways, which may result in subsequent organ dysfunction. In the present study, we hypothesized that the addition of nitric oxide, prostaglandin E<em>1</em> (PGE<em>1</em>), and aprotinin to the systemic circulation, hereby referred to as blood hibernation, would attenuate the inflammation and coagulation induced by CPB.

METHODS

Thirty adult mongrel dogs were equally divided into five groups, anesthetized and placed on hypothermic CPB (3<em>2</em> degrees C). Each group received respectively the following treatments: (<em>1</em>) inhalation of 40 ppm nitric oxide; (<em>2</em>) intravenous infusion of <em>2</em>0 ng x kg(-<em>1</em>) x min(-<em>1</em>) of PGE<em>1</em>; (3) 80,000 kallikrein inhibitor units (KIU)/kg of aprotinin; (4) the combination of all three agents (blood hibernation group); and (5) no treatment (control group) during CPB. Activation of leukocyte, platelet, endothelial cell, and formation of thrombin were assessed after CPB.

RESULTS

As compared with the other four groups, leukocyte counts were higher, while plasma elastase, interleukin-8, CD<em>1</em><em>1</em>b mRNA expression, myeloperoxidase activities and lung tissue leukocyte counts were lower in the blood hibernation group (P < 0.05 versus other four groups after CPB). Plasma prothrombin fragment (PTF)<em>1</em>+<em>2</em>, and platelet activation factors were lower, while platelet counts were higher in the blood hibernation group (P < 0.05 versus other four groups at 6 and <em>1</em><em>2</em> hours after CPB). Electron microscopy showed endothelial pseudopods protrusion, with cell adherence in all four groups except the blood hibernation group where endothelial cells remained intact.

CONCLUSIONS

Blood hibernation, effected by the addition of nitric oxide, PGE<em>1</em> and aprotinin to the circulating blood during extra-corporeal circulation, was observed to attenuate the inflammation and coagulation induced by cardiopulmonary bypass, most likely by inhibiting the important common intermediates between the two cross-linked processes.

Recent studies have shown that patients with antiphospholipid antibodies (aPL) have increased lipid peroxidation. We evaluated the urinary excretion of <em>1</em><em>1</em>-dehydro thromboxane B<em>2</em> (<em>1</em><em>1</em>-DH-TXB(<em>2</em>) and isoprostane F(<em>2</em>alpha)III (IPF(<em>2</em>alpha)III), reflecting platelet activation and lipid peroxidation in vivo, and plasma soluble markers of endothelial cell, platelet and blood coagulation activation: soluble vascular cell adhesion molecule-<em>1</em> (sVCAM-<em>1</em>), P- and E-selectin (sPsel and sEsel), F<em>1</em> + <em>2</em> <em>fragment</em> of <em>prothrombin</em> (F<em>1</em> + <em>2</em>), thrombin-antithrombin complexes (TAT) and D-Dimer (DD). We studied 79 patients with aPL (47 with previous thrombosis), 45 healthy volunteers (normal controls, NC), <em>1</em><em>2</em> patients with systemic lupus erythematosus (SLE) without aPL and a thrombosis control group (TCG) without thrombophilia (n = <em>1</em>6). Urinary levels (mean, range) of eicosanoids and isoeicosanoids were significantly increased in 39 patients with aPL compared with <em>2</em>5 NC, <em>1</em><em>1</em>-DH-TXB(<em>2</em>) <em>1</em>64.0 ng/mmol creatinine (9.5-<em>1</em><em>1</em>6<em>2</em>.8) versus 43.4 ng/mmol creatinine (4.<em>2</em>-87.6), P < 0.00<em>1</em>; IPF(<em>2</em>alpha)III 56.9 pg/mg creatinine (5.5-388.7) versus <em>2</em>7.0 pg/mg creatinine (4.6-87.6), P = 0.03. Both metabolites were significantly correlated (rho = 0.49, P = 0.0<em>1</em>4), but none correlated with any clinical manifestation or antibody profile. The aPL group presented increased levels of sPsel, sEsel, sVCAM-<em>1</em>, TAT, F<em>1</em> + <em>2</em> and DD, but any soluble marker correlated with IPF<em>2</em>alphaIII. Urinary <em>1</em><em>1</em>-DH-TXB(<em>2</em>) correlated with sPsel (rho = 0.39, P = 0.04). Compared with SLE controls, the SLE group with aPL had higher levels of F<em>1</em> + <em>2</em>. Plasma levels of F<em>1</em> + <em>2</em> and DD were significantly increased and a trend to higher sPsel was found in aPL patients with thrombosis compared with the TCG. Platelet activation, lipid peroxidation and blood coagulation activation seem to be important in the pathophysiology of antiphospholipid syndrome.

The aim of this study was to determine the extent of change in platelet and coagulation markers in the acute phase of ischemic stroke and to assess the utility of marker measurement in stroke subtype classification. Urinary <em>1</em><em>1</em>-dehydro-thromboxane B(<em>2</em>) (<em>1</em><em>1</em>-dTXB<em>2</em>), a marker of in vivo platelet activation, and markers of coagulation activation, including <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> (F<em>1</em>+<em>2</em>), thrombin-antithrombin complex (TAT), and fibrinogen, were measured in <em>2</em>5 patients with ischemic stroke within <em>2</em>4 h of onset of symptoms. Marker levels in patients with ischemic stroke were compared with those in <em>1</em>9 age-matched controls who had not taken aspirin for at least <em>2</em> weeks before sampling and <em>2</em>5 healthy controls. Median marker levels were significantly increased in stroke over those in age-matched controls for fibrinogen (344 vs. <em>2</em>89 mg/dl; P=0.030), F<em>1</em>+<em>2</em> (<em>1</em>.40 vs. 0.80 nmol/l; P=0.003), and TAT (6.65 vs. <em>2</em>.<em>2</em>0 microg/l; P<0.000<em>1</em>). Median marker levels for seven patients with cardioembolic stroke and <em>1</em>8 with non-cardioembolic stroke were not significantly different for any marker test. Eight patients taking aspirin at the time of the stroke had significantly lower <em>1</em><em>1</em>-dTXB<em>2</em> values than patients not taking aspirin (964 vs. 4,3<em>1</em>4 pg/mg of creatinine; P=0.007). Stroke patients not taking aspirin had significantly higher <em>1</em><em>1</em>-dTXB<em>2</em> concentration than age-matched controls (4,3<em>1</em>4 vs. <em>1</em>,788 pg/mg of creatinine; P=0.006). Coagulation and platelet activation markers are increased in the acute phase of stroke regardless of the clinical mechanism. This finding suggests that the markers may not be useful for predicting clinical subtype of ischemic stroke in the acute phase.

We recently reported that the serum level of macrophage colony-stimulating factor (M-CSF) was elevated in patients with cerebral infarction. In the present study, we measured serum M-CSF level, as well as coagulo-fibrinolytic markers and general laboratory tests in adult healthy subjects of various ages, and investigated the relationship between age and M-CSF level. M-CSF in aged subjects >>or=65 years of age) was significantly higher than that in the younger subjects (<65 years of age), and a significant positive correlation between age and M-CSF was found. Significant positive correlations between M-CSF, and plasma levels of thrombomodulin (TM), von Willebrand factor antigen (vWF), thrombin-antithrombin III complex (TAT), <em>prothrombin</em> <em>fragment</em> <em>1</em>+<em>2</em> (F<em>1</em>+<em>2</em>), d-dimer products cross-linked fibrin degradation products (d-dimer) and plasmin-antiplasmin complex (PAP) were also found. Among the general laboratory tests, there was only a significant correlation between M-CSF and serum creatinine; however, no significant correlation was found between M-CSF and other tests including blood cell counts. From these results, age-related elevation of serum M-CSF level was confirmed, and was suggested not to indicate the alteration of hemopoietic condition in aged subjects but to be related to thrombotic state or systemic damaged blood vessel in the apparently healthy aged people.

OBJECTIVE

Lipoproteins and coagulation factors are independent predictors of atherothrombotic events in the general population and their interaction may contribute to the development of cardiovascular damage. This study was designed to assess relationships between lipoproteins, haemostatic variables, and atherosclerotic complications in hypertensive patients.

METHODS

In 389 untreated essential hypertensive patients recruited at a hypertension clinic, we measured plasma lipids, apolipoproteins, lipoprotein (a), apolipoprotein (a) isoforms, fibrinogen, and parameters that directly reflect the coagulation activation. Hypertensive patients were compared to 9<em>2</em> normotensive controls.

RESULTS

Univariate analysis showed log lipoprotein (a) concentrations to be significantly correlated with age (P< 0.0<em>2</em>), apolipoprotein B (P< 0.0<em>2</em>), plasma fibrinogen (P< 0.00<em>1</em>), and fibrin D-dimer (P< 0.00<em>1</em>) levels, but not with body mass index, blood pressure, dietary fat intake, cholesterol, triglycerides, apolipoprotein Al, <em>prothrombin</em> <em>fragment</em> <em>1</em> + <em>2</em>, and antithrombin III. The relationship of lipoprotein (a) with fibrinogen and D-dimer was present in both sexes, whereas the relationship of lipoprotein (a) with age and apolipoprotein B was found only in males. Multiple regression analysis showed that both fibrinogen and D-dimer were independently related with lipoprotein (a). Elevated fibrinogen, D-dimer, and lipoprotein (a) levels were significantly and independently associated with clinical evidence of atherosclerotic disease. To investigate whether the relationships of lipoprotein (a) with coagulation parameters are genetically determined, we analysed apolipoprotein (a) phenotypes in a subset of <em>1</em>88 hypertensive patients. While lipoprotein (a) levels were inversely correlated with apolipoprotein (a) isoform protein size, both fibrinogen and D-dimer concentrations were comparable in patients with apolipoprotein (a) isoforms of different size.

CONCLUSIONS

This study demonstrates a relationship between lipoprotein (a) and clotting variables in hypertensive patients that may contribute to atherosclerotic damage in these patients. There is no evidence of a genetic background for this relationship.