Levels Of Fibrin Degradation Products Research Articles

Gabexate mesilate, a synthetic protease inhibitor, reduces ischemia/reperfusion injury of rat liver by inhibiting leukocyte activation.

To investigate whether gabexate mesilate, a synthetic protease inhibitor with anticoagulant properties, prevents hepatic damage by inhibiting leukocyte activation, we examined its effect on ischemia/reperfusion injury of rat liver in which activated leukocytes play a critical role. Prospective, randomized, controlled study. Research laboratory at a university medical center. Male Wistar rats weighing 220 to 280 g. Hepatic damage was evaluated by changes in bile flow and serum transaminase concentrations after ischemia/ reperfusion. Rats received continuous intravenous infusions of gabexate mesilate (10 mg/kg/hr) or intravenous administration of an inactive derivative of activated factor X (Xa), a selective inhibitor of thrombin generation (3 mg/kg), immediately before the induction of ischemia in the median and left lobes of the liver. To determine whether gabexate mesilate inhibits leukocyte activation, we examined the effects of gabexate mesilate on hepatic concentrations of tumor necrosis factor-alpha and rat interleukin-8 and on hepatic myeloperoxidase activity after ischemia/reperfusion. Hepatic dysfunction, observed after 60 mins of ischemia/reperfusion, showed a reduction in bile flow. The ischemia/reperfusion-induced decrease in bile flow was prevented by administration of gabexate mesilate. Serum transaminase concentrations increased after hepatic ischemia/reperfusion, peaking 12 hrs after reperfusion. Gabexate mesilate significantly inhibited the ischemia/reperfusion-induced increase in serum transaminase levels seen 12 hrs after reperfusion. Although an inactive derivative of factor Xa inhibited the increases in serum levels of fibrin and fibrinogen degradation products 6 hrs after reperfusion, it did not prevent ischemia/ reperfusion-induced liver injury. Hepatic levels of tumor necrosis factor-alpha, rat interleukin-8, and myeloperoxidase were significantly increased after ischemia/reperfusion. These increases were significantly inhibited by gabexate mesilate but unaffected by an inactive derivative of factor Xa. Gabexate mesilate reduced ischemia/reperfusion-induced hepatic injury not by inhibiting coagulation, but by inhibiting leukocyte activation.

Hemostatic molecular markers before the onset of disseminated intravascular coagulation.

We retrospectively measured various hemostatic markers in 240 patients with disseminated intravascular coagulation (DIC) before the onset of DIC and in 110 non-DIC patients, and examined their usefulness for the diagnosis of pre-DIC. Changes in prothrombin time ratio and fibrinogen levels were not significant before the onset of DIC. The plasma levels of fibrinogen and fibrin degradation products before the onset of DIC were increased and the platelet count was gradually reduced in nonleukemic patients; these changes were already significant in the non-DIC state. The plasma levels of thrombin-antithrombin complex (TAT), plasmin-plasmin inhibitor complex (PPIC), D-dimer, and soluble fibrin monomer (sFM) were increased before the onset of DIC. In leukemic patients, the plasma levels of sFM on day 5, those of TAT on day 3, and D-dimer on day 1, were significantly increased before the onset of DIC. The levels of most hemostatic markers 7 days before the onset of DIC were not different from those observed in the non-DIC state. In nonleukemic patients, only D-dimer, sFM, and TAT levels were significantly increased 7 days before the onset of DIC compared with values in the non-DIC state. The positive rate of hemostatic markers for the diagnosis of DIC, TAT, and PPIC were high during the pre-DIC and non-DIC groups. The plasma levels of sFM and D-dimer were low in non-DIC and increased gradually during the pre-DIC state. These findings suggest that hemostatic molecular markers such as sFM, D-dimer, and TAT are useful for the diagnosis of pre-DIC, although their cutoff values were different among various diseases.

Evaluation of secondary haemostasis in canine leishmaniasis

Secondary haemostasis was evaluated in 26 dogs with leishmaniasis and 10 normal dogs by measurements of modified one-stage prothrombin time (m-OSPT), activated partial thromboplastin time (APTT), thrombin time, fibrinogen concentration...

Coagulation and Fibrinolysis during Laparoscopic Cholecystectomy

Laparoscopic surgery appears to be less traumatic to the patient than open surgery, but its influence upon coagulation and fibrinolysis is incompletely elucidated. Our aim was to measure markers of coagulation and fibrinolysis before, during. and after laparoscopic cholecystectomy (LC). Blood samples drawn on admission, on four occasions during operation as well as 2 hours after operation and on the first postoperative day in 50 patients undergoing elective LC were analyzed for prothrombin fragment 1+2 (F1+2), soluble fibrin (SF), D-dimer (DD), fibrin degradation products (FbDP), tissue-type plasminogen activator (tPA) activity and antigen, and plasminogen activator inhibitor (PAI) activity and antigen. F1+2, SF, DD, and FbDP levels increased significantly after LC. Differences between pre- and postoperative PAI and tPA levels were not significant apart from a transient increase in tPA antigen levels. tPA activity was significantly increased during operation.

Involvement of interleukin-6 in the elevation of plasma fibrinogen levels in lung cancer patients.

Involvements of interleukin-6 (IL-6) and fibrinogen in cancer development have been independently studied. However, the association of these molecules in cancer patients remains uncertain. This study was conducted to clarify the association according to the clinicopathological characteristics of lung cancer patients. Serum IL-6 levels assayed in 339 patients without pleural effusion were assessed according to clinical stage, histological type of the cancer and levels of fibrin (ogen) degradation products (FDP), and C-reactive protein (CRP). Elevations of serum IL-6 levels more than 4 pg/ml were found in 37.8% of all patients. According to the clinical stage and histological type, the elevations were significantly more frequent in the advanced stage (44.7%), in squamous cell (49.1%) and large cell carcinomas (63.6%). Similarly, the frequency of the elevated cases (> 400 mg/dl) and the mean value of the fibrinogen level were also higher in the advanced stage (54.2%, 455.0 mg/dl) and large cell carcinoma (54.6%, 459.3 mg/dl), respectively. The elevations of fibrinogen, FDP and CRP levels were found to be related to those of the IL-6 level. In lung cancer, serum IL-6 elevations are particularly frequent in the advanced stages of patients with squamous cell and large cell carcinoma, which are associated with the elevated levels of fibrinogen, suggesting a possibility that IL-6 was involved not only directly, but also indirectly, through regulating plasma fibrinogen with promotion of cancer development in vivo.

Hemostasis in the uteroplacental and peripheral circulations in normotensive and pre-eclamptic pregnancies

OBJECTIVE: Our purpose was to determine the hemostatic changes in the uteroplacental and peripheral circulations in normotensive and pre-eclamptic pregnancies. STUDY DESIGN: This prospective, observational study involved 2 patient groups. Group 1 consisted of 30 normotensive women and 22 women with pre-eclampsia who were followed up longitudinally through pregnancy and post partum. Group 2 consisted of 20 women with established pre-eclampsia and 19 normotensive control subjects, all undergoing cesarean section. Plasma levels of thrombin–antithrombin III complex, soluble fibrin, plasmin–α 2-antiplasmin complex, and fibrin-degradation product (D-dimer) were measured in blood drawn from the antecubital vein (group 1) and from both the antecubital and uterine veins (group 2). Data were analyzed by analysis of variance. RESULTS: In group 1 levels of thrombin–antithrombin III complex, soluble fibrin, and fibrin-degradation product were significantly higher during normal pregnancy than at 6 weeks post partum. Plasmin–α 2-antiplasmin complex levels did not change. No differences between the pre-eclamptic and normotensive pregnancy groups were found for any of the hemostatic markers. In group 2 normotensive women undergoing cesarean section, thrombin–antithrombin III complex and soluble fibrin levels were significantly higher in the uterine vein than in the antecubital vein. In group 2 women with pre-eclampsia, thrombin–antithrombin III complex and fibrin-degradation product levels were significantly higher in the uterine vein than in the antecubital vein. In addition, plasmin–α 2-antiplasmin complex and fibrin-degradation product levels were higher and soluble fibrin levels were lower in the uterine vein in the pre-eclamptic group than in the normotensive group. CONCLUSION: Both the coagulation and fibrinolytic systems are activated during normal pregnancy. Activation of these systems is more marked in the uteroplacental circulation than in the systemic circulation in both normotensive and pre-eclamptic pregnancies. An abnormal pattern of hemostasis occurs in the uteroplacental circulation in pre-eclampsia. (Am J Obstet Gynecol 1998;179:520-6.)

Hemostatic molecular markers before onset of disseminated intravascular coagulation in leukemic patients.

The changes in various hemostatic parameters were examined within a period from 7 days before the onset of disseminated intravascular coagulation (DIC) in 114 patients (i.e. in their pre-DIC state). The changes in prothrombin time (PT) ratio and fibrinogen levels were not significant before the onset of DIC. Plasma fibrinogen and fibrin degradation products (FDP) levels before the onset of DIC were high, but these changes were already significant in 110 non-DIC patients examined. Plasma thrombin-antithrombin complex (TAT), plasmin-plasmin inhibitor complex (PPIC), D-dimer and soluble fibrin monomer (SFM) levels were high before the onset of DIC. In the 110 leukemic DIC patients, the plasma SFM levels were significantly increased 5 days before, the plasma TAT levels were significantly increased 3 days before, and the D-dimer levels were significantly increased 1 day before the onset of DIC. The plasma tissue factor and plasminogen activator inhibitor-I levels were not significantly changed before the onset of DIC. The PT ratio, fibrinogen, FDP, platelet count, antithrombin, D-dimer, and PPIC levels at 7 days before the onset of DIC were not significantly different from the corresponding values in the non-DIC group, although the hemostatic molecular markers SFM, D-dimer, and TAT are useful for the diagnosis of pre-DIC. Plasma thrombomodulin levels were significantly increased in these patients who died, and plasma antithrombin and protein C activities markedly reduced in the patients who died. The outcome of the diseases underlying DIC is related to vascular endothelial cell injuries.

Negative Reexploration for Cardiac Postoperative Bleeding: Can It Be Therapeutic?

Background. Reexploration of the mediastinum for bleeding is required in 3% to 7% of patients after cardiac operation, with many proving to have no surgically correctable cause. In spite of a “negative exploration,” the bleeding often ceases. We propose the hypothesis that such a negative exploration can be therapeutic by reducing marked fibrinolytic activity in the mediastinal cavity. Methods. Fibrinolytic activity in shed mediastinal blood was compared with that in the system blood in 5 patients after cardiac operation by measuring fibrinogen, fibrin degradation product, plasminogen activator inhibitor-1, and α 2-antiplasmin levels. Results. Fibrinolytic activity in mediastinal blood was markedly increased when compared with paired systemic venous blood. This was indicated by the mediastinal blood’s lower fibrinogen levels (0.47 versus 1.91 U/mL; p < 0.001), very high levels of fibrin degradation products (1,350 versus 200 ng/mL; p < 0.05), and higher levels of plasminogen activator inhibitor-1 (55.5 versus 28.1 ng/mL; p < 0.005). Decreased levels of α 2-antiplasmin were also observed in the mediastinum (0.50 versus 0.61 U/mL; p < 0.05). Conclusions. Our data confirm that fibrinolytic activity can be extremely high in the mediastinum in response to clot formation. This may explain the hemostatic effects of a negative reexploration, where irrigation and the removal of clots may reduce the fibrinolytic process; this may allow the bleeding ends of capillaries and small vessels to thrombose. Decreased levels of α 2-antiplasmin observed suggest that lysine analogs, such as ϵ-aminocaproic acid, may have a beneficial role when locally delivered into the mediastinum.

Plasma levels of D-dimer and circulating endothelial adhesion molecules in veno-occlusive disease of the liver following allogeneic bone marrow transplantation.

Veno-occlusive disease (VOD) of the liver is a frequent and life-threatening complication of BMT. Recently, successful treatment by t-PA has been reported but has been compromised by fatal bleeding events. Therefore, t-PA application should be restricted to patients with severe VOD. However, moderate and severe forms of VOD are difficult to distinguish in early stages. We analyzed plasma levels of cross-linked fibrin degradation products (D-dimer) and soluble endothelial adhesion molecules such as sE-selectin, sVCAM-1 and sICAM-1 in 10 consecutive patients undergoing allogeneic BMT to evaluate their use in identifying severe forms of VOD. During the observation period, 4 episodes of VOD occurred, 2 of which were fatal due to early onset of multiorgan failure. Concentrations of D-dimer generally increased after transplantation. However, there was an additional significant increase in D-dimer levels during severe VOD. Thus, D-dimer levels above 1000 microg/l were only found in 2 cases with severe VOD and fatal outcome. When compared with bilirubin concentrations substantial increases of D-dimers appeared earlier during the course of severe VOD. In contrast, VOD episodes were not accompanied by significant increases in sE-selectin, sVCAM-1 and sICAM-1 levels. It is concluded that measurement of D-dimer concentrations may aid accuracy to the early diagnosis of severe VOD.

PLATELET AGGREGATION IN PATIENTS BITTEN BY THE BRAZILIAN SNAKE Bothrops jararaca

Patients bitten by the lancehead snake Bothrops jararaca usually develop systemic bleeding. Our aim was to evaluate platelet function in whole blood of 17 human patients bitten by this snake in São Paulo State, Brazil. Bleeding occurred in 71% of these patients, and thrombocytopenia in 53% of them. On admission, most of the patients presented with hypoaggregation to 50 μM ADP and 1.2 mg/ml ristocetin, and only 35% of them to 5 μg/ml collagen. Abnormal plasma levels of fibrinogen and fibrin(ogen) degradation products (FDP/fdp) were also observed. Twenty-four hours of finishing serumtherapy, bleeding had already ceased, fibrinogen and FDP/fdp levels returned to hemostatic levels, and values for platelet aggregation returned to the reference range of controls, except for ADP that still remained decreased. These findings evidence that disturbances of platelet function are also an important factor for the development of bleeding in Bothrops envenomation, as well as other known hemostatic disturbances that occur concomitantly. © 1997 Elsevier Science Ltd

Prospective, Randomized, Double-Blind Study of High-Dose Aprotinin in Pediatric Cardiac Operations

Background. Perioperative aprotinin decreases postoperative blood loss in adults undergoing cardiac operations, but its role is less clear in children. Therefore, a trial of aprotinin in pediatric cardiac operations was conducted to study the efficacy of its use in children.Methods. Forty-two patients were randomly assigned to receive either high-dose aprotinin or placebo. Aprotinin efficacy was assessed using time from protamine administration to skin closure, postoperative blood loss and hemoglobin loss, and postoperative transfusion requirements. Measures of fibrinolysis (fibrin degradation product titers) and platelet preservation (β-thromboglobulin levels) were also assessed.Results. There were no statistically significant differ- ences between groups in any of the blood loss or transfusion parameters. Fibrin degradation product levels, measured 4 hours postoperatively, had increased significantly for control patients, but remained unchanged for the aprotinin group (p < 0.02). β-Thromboglobulin levels increased more rapidly during cardiopulmonary bypass in the control group (p = 0.03).Conclusions. Aprotinin appears to provide no clinical benefit in routine pediatric cardiac operations. A reduction in fibrinolysis, with perhaps an early preservation of platelet structure, is seen in the aprotinin group.(Ann Thorac Surg 1997;63:497–503)

The rate of fibrinolysis is increased by free retraction of human gingival fibroblast populated fibrin lattices

We previously demonstrated that human gingival fibroblasts (HGF), but not their dermal counterparts, when seeded in retracting fibrin lattices induced intense fibrinolysis that was observed at the earliest stages of contraction and led to complete matrix degradation by day 7 of culture. Our aim was to examine the influence of mechanical forces in such fibrinolytic processes. HGF were seeded in retracting (R) e.g. free floating or non retracting (NR) e.g. anchored fibrin lattices (FL). Cultures were analysed from day 1–12 by phase contrast microscopy and scanning electron microscopy (s.e.m.). Levels of fibrin degradation products (FDP) and tissue plasminogen activator (tPA) accumulating in culture media were quantified by ELISA. Urokinase (uPA) and gelatinase A (MMP 2) were identified by zymographic techniques. At the s.e.m. level, vacuolization around some HGF was noticed at the earliest stages of culture for RFL and complete degradation of lattices occurred at day 7. Formation of lysed matrix cavity was far less intense in NRFL even after 12 days of culture. FDP amounts at day 4 of culture were equal to 79 ± 14 and 8.5 ± 0.6 μg/10 5 cells for RFL and NRFL, respectively; tPA levels were equal to 5.8 ± 0.6 (RFL) and 2.1 ± 0.3 ng/10 5 cells (NRFL) and differences were still evident at day 7. The kinetics of tPA production were identical in either retracting fibrin or collagen lattices. On the contrary, uPA and proMMP 2 productions were similar in RFL and NRFL. Isometric forces, but not the matrix support, were responsible for accelerated tPA production and fibrinolysis in HGF populated lattices.

Fibronectin, platelet factor 4 and beta-thromboglobulin in endemic hepatosplenic schistosomiasis: relation to acute hematemesis.

Some platelet alpha-granule contents were assessed in parallel with other markers of hemostatic imbalance in 50 patients with hepatosplenic schistosomiasis (15 patients with compensated hepatosplenomegaly, 15 patients with advanced hepatic fibrosis and ascites and 20 patients during an acute attack of hematemesis from ruptured esophageal varices). Platelet factor 4 (PF4), beta-thromboglobulin (beta-TG), fibronectin (FN), prothrombin fragment 1 + 2, thrombin-antithrombin (TAT) complexes, fibrin degradation products (FbDP) and D-dimer were assessed in schistosomal patients compared to controls (15 healthy subjects). A significant increase in both thrombin (high TAT and prothrombin fragment 1 + 2 levels) and plasmin (high FbDP and D-dimer levels) generation was detected in decompensated patients establishing the presence of a steady state of low-grade disseminated intravascular coagulation, with and without overt bleeding, in these patients. A decrease in plasma FN concentration was found in diseased groups compared to controls. The reduction in plasma levels of FN paralleled the defective liver function and matched the relative decrease in tissue FN in liver specimens of decompensated patients suggesting that FN levels can be used to evaluate the pathological staging of the disease. A significant increase in beta-TG and PF4 levels was noted in decompensated patients with ascites and/or acute hematemesis compared both to controls and compensated patients reflecting platelet alpha-granule release and consequently increased in vivo platelet activation which may initiate and/or perpetuate the pathophysiological mechanisms of the hemostatic imbalance underlying the hemorrhagic diathesis in hepatosplenic schistosomiasis.

Effects of a highly selective synthetic inhibitor of plasma kallikrein on disseminated intravascular coagulation in rats

We found a new, highly selective plasma kallikrein inhibitor, trans-4-aminomethyl-cyclohexanecarbonylphenylalanine 4-carboxymethylanilide hydrochloride, called PKSI-527 in our laboratories. This study was conducted to evaluate PKSI-527, on thromboplastin (TP)- and endotoxin (LPS)-induced disseminated intravascular coagulation (DIC) in rats. PKSI-527 was infused intravenously at 0.1 mg/kg/min for 250 min. Three of the parameters of the coagulation and fibrinolysis system, fibrinogen level, platelet counts and fibrin(ogen) degradation products (FDP) level were assayed. PKSI-527 prevented the change in the coagulation and fibrinolysis system in LPS-induced DIC, however it was not clearly effective in TP-induced DIC. The parameters of organ failure, such as serum glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), creatine phosphokinase (CPK), lactate, blood urea nitrogen and β-glucuronidase, were assayed. Although the changes in the fibrinogen level, platelet counts and FDP level were almost the same in both models, the parameters of organ failure apparently increased in LPS-induced DIC more so than in TP-induced DIC. PKSI-527 significantly suppressed the increases in GOT and GPT in LPS-induced DIC. These results indicate that plasma kallikrein may play a significant role in LPS-induced DIC. Therefore, PKSI-527, as a synthetic plasma kallikrein inhibitor may be a valuable tool to explore the mechanism of DIC and the accompanying organ failure.

Association between High Values of D-dimer and Tissue-plasminogen Activator Activity and First Gastrointestinal Bleeding in Cirrhotic Patients

Cirrhotic patients with decompensated state and high serum levels of fibrin(ogen) degradation products are at high risk of bleeding. The aim of this study was to further analyse the relationship between hyperfibrinolysis and bleeding in cirrhosis by measuring plasma values of D-dimer and tissue plasminogen activator (t-PA) activity. One-hundred-twelve cirrhotic patients with oesophageal varices and without previous upper-gastrointestinal bleeding entered the study and were followed-up for 3 years. Patients were considered to have hyperfibrinolysis if they concomitantly had high values of D-dimer and t-PA activity. During the follow-up 34 (30%) patients bled. They had more severe liver failure (p = 0.0001) and variceal size (p = 0.0031) and higher prevalence of ascites (p = 0.0003), varices with red signs and hyperfibrinolysis (p = 0.0001) than patients who did not bleed. Multivariate analysis disclosed hyperfibrinolysis as the only marker predictive of bleeding (Hazard Ratio = 42.5, p < 0.001). Our findings suggest that screening for hyperfibrinolysis may be useful to identify cirrhotic patients at risk of bleeding.

Fibrinogen and markers of fibrinolysis and endothelial damage following resolution of critical limb ischaemia

To assess the effects of resolution of critical limb ischaemia on the elevated plasma fibrinogen, cross-linked fibrin degradation products (FDP), and von Willebrand factor antigen (vWF) levels, reported in peripheral arterial occlusive disease. A prospective study of patients undergoing surgery for chronic critical limb ischaemia. Two vascular surgery units providing tertiary referral services for the West of Scotland. Venous blood samples were assayed for plasma fibrinogen, FDP D-dimer, and vWF levels, prior to surgery, together with fibrinolytic and rheological parameters, in 82 patients. Sampling was repeated 4 months after resolution of critical limb ischaemia. Levels of these parameters following successful resolution of critical limb ischaemia were compared with pre-operative levels, and with an age-matched random population sample. Plasma fibrinogen and vWF levels were significantly lower (both p < 0.005, Wilcoxon matched pairs) following successful resolution of critical limb ischaemia in the 56 patients available for review, although levels remained higher than in population controls (p < 0.01, Mann-Whitney U-test). FDP levels were unchanged following surgery, remaining higher than in age-matched population controls (p < 0.01). Resolution of critical limb ischaemia fails to reduce plasma fibrinogen, fibrin turnover, and vWF levels to those seen in population controls. This implies that increased fibrinogen and fibrin turnover in peripheral arterial disease is not solely a consequence of tissue ischaemia, while the persisting prothrombotic state following resolution of critical limb ischaemia has potentially important implications for graft and patient survival.

Treatment of acute myocardial infarction with streptokinase does not appear to modulate circulating neutrophil function.

The administration of thrombolytic therapy is the most common method of achieving patency of the occluded coronary artery in patients with acute myocardial infarction (AMI). However, thrombolytic agents and the byproducts of fibrinolysis have the potential to affect neutrophil activation and thus function, thereby augmenting myocardial damage further. This study assessed the effect of streptokinase administration on the function of circulating neutrophils in patients with AMI. For this neutrophil adherence to human umbilical vein endothelial cells, homotypic neutrophil aggregation, and CD11b and L-selectin expression on the neutrophil membrane prior to and 1 h and 6 h after thrombolytic therapy was monitored. The study population included patients with AMI who received aspirin and streptokinase, and healthy laboratory workers who received aspirin only; all subjects acted as their own controls. Circulating fibrin degradation products and white cells were markedly raised following administration of streptokinase. No significant differences in neutrophil adherence to endothelium, homotypic neutrophil interactions, and CD11b or L-selectin expression were demonstrated between neutrophils, either pre- or post-thrombolytic therapy in the infarct group, or between neutrophils from the infarct group and from the control group. It was concluded that streptokinase produces an abrupt neutrophil leukocytosis together with a marked increase in circulating levels of fibrin degradation products. The assay systems used were unable to show significant sequential changes in circulating neutrophil adhesion and L-selectin or CD11b expression in patients with AMI following thrombolytic therapy or when these patients were compared with controls.

Improved lung function by urokinase infusion in canine lung transplantation using non-heart-beating donors

We evaluated the effect of urokinase on pulmonary microthrombi formation of the donor lung using a canine cadaver left lung allotransplantation model. Donor animals were sacrificed with an intravenous injection of potassium chloride without heparinization and were divided into three groups. In group 1 (n = 6), cadavers were left at room temperature for 1 hour, and lung retrieval was then performed after flushing the lung block with low potassium-dextran-glucose solution. Donor lungs were stored for 3 hours at 8 degrees C. In group 2 (n = 6), donor lungs were treated as in group 1 except that the cadavers were left at room temperature for 2 hours instead of 1 hour before lung retrieval. In group 3 (n = 6), donor lungs were treated as in group 2 except that high-dose urokinase (120,000 IU) was injected into the main pulmonary artery after flushing with low-potassium-dextrose-glucose solution. In all groups after left lung transplantation, the right pulmonary artery was ligated, and recipient animals were followed up for 6 hours after reperfusion. The fibrin degradation product level in the donor lung tissue was also measured. All recipient animals in group 1 survived the 6-hour observation period with excellent gas exchange and stable hemodynamics. Group 3 had significantly better gas exchange than group 2 and similar cardiopulmonary function as group 1. The fibrin degradation product level in the donor lungs before transplantation was significantly higher in group 3 than in group 2.(ABSTRACT TRUNCATED AT 250 WORDS)

Fibrin degradation product (FnDP) assays: analysis of standardization issues and target antigens in plasma

The in vivo formation of fibrin and its subsequent secondary fibrinolytic digestion yields a variety of crosslinked fibrin degradation products (XL/FnDP). One of these is known as D-dimer and a variety of ELISA-type commercial kits using monoclonal antibodies to D-dimer have been developed. We have investigated the possibility of establishing a standard such that these various kits might indicate the same levels of D-dimer in the same samples. We have concluded that because it seems that each individual monoclonal antibody to D-dimer targets a unique and distinct epitope in the FnDP fraction the notion of introducing a standard D-dimer which will respond uniformly to each D-dimer monoclonal antibody is not feasible. Using various monoclonal and polyclonal antibodies in conjunction with gel exclusion chromatography we have examined human plasma derived from patients with disseminated intravascular coagulation (DIC) which contained high levels of fibrin degradation products (FnDP). The data suggested that the FnDP fraction in plasma contained mostly high molecular weight (> 2 x 10(6) daltons) crosslinked fragments which contain high levels of fibrinopeptide A. Many of these crosslinked fragments crossreact with antibodies to D-dimer because they each contain D-dimer as a structural component. On the basis of this data, a novel sequence of events is proposed which may occur during the aggregation of fibrin in vivo.

Measuring plasma fibrinogen levels in patients with liver cirrhosis. The occurrence of proteolytic fibrin(ogen) degradation products and their influence on several fibrinogen assays

In patients with liver cirrhosis the fibrinogen molecule is under constant attack of various proteolytic enzymes, which might affect results of the different assay systems for fibrinogen. We therefore studied the measurement of fibrinogen in the plasma of patients with mild, moderate and severe cirrhosis of the liver. Fibrinogen levels were measured with the Clauss method (functional fibrinogen); an enzyme immuno assay (EIA) for HMW + LMW fibrinogen; and an assay that measures the total clottable fibrinogen. With all three methods we found normal or slightly increased fibrinogen levels in patients with mild or moderate cirrhosis, whereas patients with severe cirrhosis had decreased levels. No evidence was found for increased partial fibrinogen proteolysis, resulting in increases of LMW'-fibrinogen in cirrhotic patients. We further observed that fibrinogen degradation products levels increased slightly with the severity of the disease, but were still in the normal range in patients with severe cirrhosis. This indicates a very low level of primary fibrinolysis. Fibrin degradation products levels increased much stronger, which points to intravascular coagulation. The levels of the fibrin degradation products remained below the level where they are expected to influence the Clauss assay. In patients with liver cirrhosis the measurement of plasma fibrinogen levels with the three studied methods give comparable results. We suggest to apply the Clauss assay in cirrhotic patients because of this and because it has a good reproducibility and because the test is cheap, quick and easy to perform.