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1.
Dig Liver Dis ; 40(11): 874-81, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18329968

ABSTRACT

BACKGROUND AND AIM: Variceal bleeding carries a high-mortality rate in patients with liver cirrhosis. Since coagulation and fibrinolysis are abnormal in these patients we evaluated whether or not abnormalities of these haemostasis systems were independently related to mortality. METHODS: Global coagulation, coagulation activation and fibrinolysis measurements were performed in 43 cirrhotics bleeding from esophageal varices at baseline and during follow-up and in 43 non-bleeding cirrhotic patients at baseline only. RESULTS: Baseline measurements of coagulation activation and fibrinolysis were more impaired in bleeders. In bleeders, prothrombin time, tissue type plasminogen activator antigen and D-dimer plasma levels were persistently more abnormal in patients who died. High-D-dimer, infection, Child-Pugh C class and MELD score >or=17 were the significant predictors of death at univariate analysis. Two different multivariate analyses to assess the independent prognostic value of these variables, one including the Child-Pugh class, the other including MELD, were performed. Independent predictors of death were high-D-dimer and infection, but not Child-Pugh class, in the former; MELD and infection, but not D-dimer, in the latter. CONCLUSIONS: Beside infection, high-D-dimer is a stronger predictor of death as compared to Child-Pugh C class, but not to a MELD score >or=17.


Subject(s)
Esophageal and Gastric Varices/blood , Fibrin Fibrinogen Degradation Products/analysis , Gastrointestinal Hemorrhage/mortality , Liver Cirrhosis/blood , Adult , Aged , Aged, 80 and over , Analysis of Variance , Biomarkers/blood , Case-Control Studies , Cause of Death , Enzyme-Linked Immunosorbent Assay , Esophageal and Gastric Varices/diagnosis , Esophageal and Gastric Varices/mortality , Female , Follow-Up Studies , Gastrointestinal Hemorrhage/blood , Gastrointestinal Hemorrhage/etiology , Humans , Linear Models , Liver Cirrhosis/diagnosis , Liver Cirrhosis/mortality , Male , Middle Aged , Predictive Value of Tests , Probability , Reference Values , Retrospective Studies , Sensitivity and Specificity , Survival Analysis
2.
Scand J Rheumatol ; 33(4): 253-6, 2004.
Article in English | MEDLINE | ID: mdl-15370722

ABSTRACT

OBJECTIVE: The prostanoids iloprost and alprostadil are widely used to treat ischaemic changes in patients with Raynaud's phenomenon (RP), but the optimal regimen is poorly defined. We evaluated whether there are differences between iloprost and alprostadil, in terms of either clinical efficacy or of laboratory data, with the aim of assisting in the treatment of connective tissue disease (CTD)-associated RP. METHODS: Twenty-one women with CTD-associated RP were given intravenous iloprost (11 patients) or alprostadil (10 patients) cyclically (5 consecutive days, followed by 1 day every 30 days). Clinical efficacy (RP symptoms, skin score, digital ulcers) and circulating levels of von Willebrand factor (VWf), tissue plasminogen activator (tPA), thrombomodulin (TM) and Type III procollagen N-terminal propeptide (PIIINP) were evaluated by enzyme-linked immunoassay at different intervals. RESULTS: The overall benefits of iloprost and alprostadil were similar. RP improved in 45% versus 90% of patients; ulcers in 60% versus 40% of patients (iloprost versus alprostadil). Skin score did not significantly change with either drug. Circulating VWf decreased with either drug (iloprost -6.2%, alprostadil -9.4%), while tPA, TM, and PIIINP remained unchanged. Side effects were only minor and less frequent with alprostadil. CONCLUSION: Iloprost and alprostadil were both of benefit in CTD-associated RP, without significant differences in either clinical efficacy or circulating markers. However, ease of handling and the lower price favours alprostadil.


Subject(s)
Alprostadil/therapeutic use , Iloprost/therapeutic use , Raynaud Disease/drug therapy , Vasodilator Agents/therapeutic use , Adult , Aged , Alprostadil/administration & dosage , Biomarkers/analysis , Connective Tissue Diseases/complications , Double-Blind Method , Enzyme-Linked Immunosorbent Assay , Female , Humans , Iloprost/administration & dosage , Infusions, Intravenous , Middle Aged , Raynaud Disease/etiology , Treatment Outcome , Vasodilator Agents/administration & dosage
3.
Am J Gastroenterol ; 99(10): 1966-70, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15447757

ABSTRACT

OBJECTIVES: Hypofibrinolysis has been proposed as a possible mechanism underlying the known risk of thrombosis observed in patients with inflammatory bowel diseases (IBD). Thrombin-activatable fibrinolysis inhibitor (TAFI) is a recently described inhibitor of fibrinolysis. Increased TAFI plasma levels are associated with a risk for venous thrombosis. The objective was to evaluate TAFI plasma levels and their possible correlations with clinical features and acute-phase reactants in IBD patients. METHODS: Eighty-one IBD patients (47 Crohn's disease and 34 ulcerative colitis) and 81 sex- and age-matched healthy controls were enrolled in the study; moreover, we studied 30 inflammatory controls (13 Reiter's syndrome, 4 Behçet's syndrome, and 13 patients with newly diagnosed celiac disease). TAFI plasma levels were assessed by means of a commercially available ELISA kit. Erythrocytes sedimentation rate, C-reactive protein, and alpha1-acid glycoprotein were measured as acute-phase reactants. Statistical analysis was performed by means of nonparametric tests and Fisher's exact test and chi(2) test for independence. RESULTS: Median TAFI plasma levels were significantly higher in IBD patients (116.0%, range: 39.0-232.0%) and in inflammatory controls (176.0%, 50.0-435.0%) than in healthy controls (99.0%, 40.0-170.0%) (p< or = 0.05 and p< or = 0.001, respectively). TAFI plasma levels higher than the 95th percentile of control values were significantly more frequent in IBD patients (19.7%) and in inflammatory controls (53.3%) than in healthy controls (4.9%) (p< or = 0.008 and p< or = 0.0001, respectively) and more frequent in clinically active IBD than in clinically quiescent IBD (31.4%vs 10.9%, p< or = 0.03). Finally, in IBD, significant correlations were observed between TAFI plasma levels and erythrocytes sedimentation rate (p< or = 0.02), C-reactive protein (p< or = 0.001), and alpha1-acid glycoprotein (p< or = 0.05). CONCLUSIONS: TAFI plasma levels are increased in IBD patients and correlate with acute-phase reactants. Increased TAFI plasma levels might contribute to the prothrombotic state observed in IBD through the induction of hypofibrinolysis.


Subject(s)
Carboxypeptidase B2/blood , Inflammatory Bowel Diseases/blood , Adult , Female , Humans , Male
4.
Clin Sci (Lond) ; 101(6): 651-7, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11724653

ABSTRACT

Bradykinin, a nonapeptide with vasodilatory and permeabilizing activity, is generated through the cleavage of high-M(r) ('high-molecular-weight') kininogen by kallikrein, and its generation is facilitated by plasmin. In the ascitic fluid of patients with cirrhosis, there is massive cleavage of high-M(r) kininogen and activation of fibrinolysis, but bradykinin has never been measured directly. In the ascitic fluid of 24 patients with cirrhosis, we measured bradykinin-(1-9)-nonapeptide levels by RIA after liquid-phase and subsequent HPLC extraction, and those of its catabolic product bradykininin-(1-5)-pentapeptide by ELISA after liquid-phase extraction. Cleaved high-M(r) kininogen, activated factor XII and plasmin-antiplasmin complexes were measured in ascitic fluid and plasma. Plasma renin activity (PRA) was also determined. As a control, we also analysed plasma from 24 healthy subjects matched for sex and age with the patients. In the ascitic fluid from patients with cirrhosis, the median bradykinin-(1-9) concentration was 3.3 fmol/ml (range 0.2-29.0 fmol/ml), and the median bradykinin-(1-5) concentration was 210 fmol/ml (range 58-7825 fmol/ml). The levels of bradykinin-(1-5) in ascitic fluid were higher in patients with refractory ascites [median 1091 fmol/ml (range 58-7825 fmol/ml)] than in patients with responsive ascites [134 fmol/ml (72-1084 fmol/ml)] (P=0.010). Ascitic fluid levels of bradykinin-(1-9) were not related to the severity of ascites. PRA was higher in patients with refractory ascites [23.0 ng x h(-1) x ml(-1) (7.9-80.0 ng.h(-1).ml(-1))] than in patients with responsive ascites [6.9 ng x h(-1) x ml(-1) (0.9-29.4 ng x h(-1) x ml(-1))] (P=0.002). In ascitic fluid, 48% (19-68%) of high-M(r) kininogen was cleaved, and plasmin-antiplasmin complexes were more concentrated than in plasma (P=0.0001). In conclusion, in the ascitic fluid of patients with cirrhosis, both bradykinin-(1-9) and bradykinin-(1-5) are present, with cleavage of high-M(r) kininogen and activation of fibrinolysis. The highest levels of the long-lived metabolite bradykinin-(1-5) were found in the ascitic fluid of patients with refractory ascites and high PRA. Activation of the kinin system may therefore be involved in decompensating cirrhosis, but a cause-effect relationship remains to be established.


Subject(s)
Ascitic Fluid/chemistry , Bradykinin/analysis , Liver Cirrhosis/metabolism , Adult , Aged , Electrophoresis, Polyacrylamide Gel , Factor XIIa/analysis , Female , Fibrinolysin/analysis , Humans , Immunoblotting , Kininogens/analysis , Liver Cirrhosis/blood , Male , Middle Aged , Peptide Fragments/analysis , Renin/blood , Serum Albumin/analysis , alpha-2-Antiplasmin/analysis
5.
J Rheumatol ; 28(4): 786-94, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11327251

ABSTRACT

OBJECTIVE: To evaluate the efficacy and safety of prostaglandin (PG) E1alpha-cyclodextrin for Raynaud's phenomenon (RP) secondary to systemic sclerosis (SSc) and its effect on variables of immune activation and endothelial injury in SSc such as tumor necrosis factor-alpha (TNF-alpha), soluble interleukin 2 receptor (sIL-2R), circulating intercellular adhesion molecule-1 (cICAM-1), von Willebrand factor (vWF), and tissue-type plasminogen activator (t-PA). METHODS: We studied 36 women with SSc, 24 of them given three 60 microg intravenous PGE1alpha-cyclodextrin infusions on 5 consecutive days at 6 week intervals during the winter. RP symptoms and healing of digital lesions were evaluated. Twenty age matched healthy women were the controls. TNF-alpha, sIL-2R, cICAM-1, vWF, and t-PA were measured after the first and last infusion of PGEE1alpha-cyclodextrin and correlated with clinical features. RESULTS: RP symptoms improved in 87% of the patients. The benefit of each 5 day cycle lasted 4 or more weeks in 75%. PGE1alpha-cyclodextrin reduced the daily frequency of RP symptoms by 20% (p < 0.05), 41% (p < 0.005), and 53% (p < 0.0005) from baseline after the 1st, 2nd, and 3rd infusions, respectively. The severity of the attacks was reduced to a limited degree. In 12 of the 14 patients with digital lesions, these healed completely. Ten patients had mild side effects during treatment (headache, increased intestinal motility, flushing). TNF-alpha, sIL-2R, cICAM-1, vWF, and t-PA plasma concentrations were significantly higher in patients with SSc than controls (p < 0.05, p < 0.001). TNF-alpha, sIL-2R, and cICAM-1 were higher in diffuse SSc and patients with lung involvement. The plasma levels of cICAM-1 and t-PA were significantly reduced after the 1st infusion of PGE1alpha-cyclodextrin (both p < 0.005) and further reduced after the last (p < 0.0005 and p < 0.005). CONCLUSION: PGE1alpha-cyclodextrin reduces RP symptoms and plasma levels of the markers of endothelial injury in SSc, suggesting that an improvement of endothelial dysfunction contributes to its prolonged therapeutic effect.


Subject(s)
Alprostadil/analogs & derivatives , Alprostadil/therapeutic use , Cyclodextrins/therapeutic use , Endothelium, Vascular/drug effects , Endothelium, Vascular/pathology , Raynaud Disease/drug therapy , Raynaud Disease/etiology , Scleroderma, Systemic/complications , alpha-Cyclodextrins , Adult , Aged , Biomarkers , Female , Humans , Immune System/drug effects , Immune System/physiopathology , Injections, Intravenous , Middle Aged , Raynaud Disease/blood , Raynaud Disease/pathology , Reference Values , Scleroderma, Localized/blood , Scleroderma, Localized/drug therapy , Scleroderma, Localized/etiology , Scleroderma, Localized/pathology , Treatment Outcome
6.
Br J Haematol ; 111(2): 467-73, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11122086

ABSTRACT

Thromboembolic phenomena have been described in patients with thalassaemia intermedia and major, although there are relatively few epidemiological data on the overall frequency of these complications. To obtain more insight into the risk and mechanism of venous thromboembolism in thalassaemia, the aims of this study were: (i) to establish retrospectively the prevalence of thromboembolic events in a large group of adults with thalassaemia intermedia and major during a follow up period of 10 years; (ii) to measure in subgroups of these patients sensitive markers of activation of coagulation and fibrinolysis enzymes; and (iii) to look for possible procoagulant mechanisms. A high prevalence of thromboembolic events was found, particularly in splenectomized patients with thalassaemia intermedia (29%). These patients had high plasma levels of markers of coagulation and fibrinolysis activation. Furthermore, thalassaemic red cells and erythroid precursors from splenectomized patients with thalassaemia intermedia had an enhanced capacity to generate thrombin. To evaluate the role of splenectomy per se on procoagulant activity, we evaluated the capacity to form thrombin in healthy individuals who had been splenectomized for trauma. They produced the same amount of thrombin as non-splenectomized controls. In conclusion, the results of this study show the existence of a hypercoagulable state in splenectomized patients with thalassaemia intermedia and that their red and erythroid cells are capable of acting as activated platelets in thrombin generation.


Subject(s)
Thalassemia/complications , Thromboembolism/etiology , Thrombophilia/etiology , Venous Thrombosis/etiology , Adult , Aged , Analysis of Variance , Erythrocytes/metabolism , Female , Follow-Up Studies , Hematopoietic Stem Cells/metabolism , Humans , Male , Middle Aged , Prevalence , Retrospective Studies , Splenectomy , Thalassemia/blood , Thalassemia/surgery , Thrombin/biosynthesis , Thromboembolism/blood , Thrombophilia/blood , Venous Thrombosis/blood
7.
Exp Clin Endocrinol Diabetes ; 108(7): 486-92, 2000.
Article in English | MEDLINE | ID: mdl-11083070

ABSTRACT

Alterations of coagulation and fibrinolytic systems might contribute to the increased cardiovascular and cerebrovascular mortality observed in patients with both chronic growth hormone (GH) excess (acromegaly) and deficiency (GHD). However, contrasting results have been so far reported. To assess the importance of GH in modulating haemostatic system, several haemostatic variables in patients with GHD and acromegaly were measured. Twenty-four adult patients with GHD (8 childhood- and 16 adult-onset; age: 41+/-12 years, insulin like growth factor-I, IGF-I: 6.7+/-4 nmol/L), 10 non-diabetic acromegalic patients (age: 39+/-15 years; IGF-I: 109+/-37 nmol/L) and 64 healthy volunteers age- and sex-matched with cases were studied. The plasma levels of tissue-type plasminogen activator antigen (t-PA), prothrombin fragment 1+2 (F1+2) and thrombin-antithrombin complex (TAT) were measured by ELISA. Plasminogen activator inhibitor type I (PAI-1) was measured by an immunoactivity assay and fibrinogen by von Clauss method. GH levels were measured by IFMA and IGF-I by RIA. GHD patients had higher PAI-1 (12.7+/-16.7 vs 4.8+/-5.3 U/ml, p<0.01), fibrinogen (363+/-104 vs 291+/-71 mg/dL, p< 0.05) and TAT levels (6.8+/-9 vs 3.6+/-2.8 ng/ml, p<0.05) than controls. Taking the 95th pecentile of the normal distribution in the control group as the cut-off point for normal plasma levels of the haemostatic variables, high PAI levels were found in 25% of patients with GHD (P<0.01), while high fibrinogen and TAT levels were observed in 21% (P<0.05). The alterations were mostly present in patients with adult-onset GHD, with the exception of hyperfibrinogenaemia which was equally present in adult- and childhood-onset patients. Acromegalic patients had higher mean fibrinogen levels than controls (398+/-111 vs 291+/-71 mg/dL, p< 0.05), 40% having hyperfibrinogenaemia (P<0.01, vs controls). They also had t-PA levels lower than controls and GHD. No correlations between hormonal and haemostatic variables were found. Body mass index and waist to hip ratio correlated positively with PAI-1 levels in GHD patients only. In conclusion, this study shows that several abnormalities of coagulation variables (increased PAI-1. fibrinogen and TAT levels) are present in patients with GHD, while only hyperfibrinogenaemia is found in patients with acromegaly. These changes do not appear to be directly related to IGF-I levels or to the degree of GH deficiency/excess. However, these abnormalities may be an additional trigger for the development of coronary heart disease and thromboembolic complications mostly in patients with GHD.


Subject(s)
Acromegaly/blood , Fibrinolysis , Hemostasis , Human Growth Hormone/deficiency , Pituitary Diseases/blood , Acromegaly/etiology , Adult , Age of Onset , Antithrombin III/analysis , Biomarkers/blood , Enzyme-Linked Immunosorbent Assay , Female , Human Growth Hormone/blood , Humans , Insulin-Like Growth Factor I/analysis , Male , Peptide Fragments/analysis , Peptide Hydrolases/analysis , Pituitary Diseases/classification , Plasminogen Activator Inhibitor 1/blood , Protein Precursors/analysis , Prothrombin/analysis , Reference Values , Tissue Plasminogen Activator/blood
8.
Arterioscler Thromb Vasc Biol ; 20(9): 2162-6, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10978264

ABSTRACT

In patients with unstable angina, intravenous heparin reduces thrombin activity but does not influence thrombin generation. Recombinant hirudin, a direct thrombin inhibitor, may be more effective in inhibiting both thrombin generation and activity. We measured the plasma levels of prothrombin fragment 1+2 (a marker of thrombin generation) and fibrinopeptide A (a marker of thrombin activity) in 67 patients with unstable angina enrolled in the GUSTO (Global Use of Strategies to Open Occluded Coronary Arteries) IIb trial who were receiving either recombinant hirudin (31 patients) or heparin (36 patients). Blood samples were obtained at baseline (before any treatment), after 3 to 5 days of study drug infusion (immediately before discontinuation), and 1 month later. In the patients receiving recombinant hirudin, the prothrombin fragment 1+2 levels measured immediately before drug discontinuation were significantly lower than at baseline (P:=0.0014), whereas they had not changed in the patients receiving heparin; at this time point, the difference between patients receiving hirudin and those receiving heparin was statistically significant (P:=0.032). One month later, the prothrombin fragment 1+2 levels in both groups were similarly persistently high and did not differ from baseline. Fibrinopeptide A plasma levels at the end of infusion were significantly lower than at baseline in both treatment groups (P:=0. 0005 for hirudin and P:=0.042 for heparin) and remained lower after 1 month (P:=0.0001 for both hirudin and heparin). The fibrinopeptide A plasma levels were not different between patients treated with hirudin versus heparin at baseline, at the end of infusion, and after 1 month. Thus, in patients with unstable angina, in vivo thrombin generation and activity are reduced during intravenous infusion of recombinant hirudin. However, the inhibition of thrombin generation is not sustained, and after 1 month, the majority of patients have biochemical signs of increased thrombin generation.


Subject(s)
Angina Pectoris/metabolism , Angina, Unstable/metabolism , Heparin/pharmacology , Hirudins/pharmacology , Thrombin/metabolism , Aged , Female , Humans , Infusions, Intravenous , Male , Middle Aged , Recombinant Proteins/pharmacology
9.
Exp Clin Endocrinol Diabetes ; 108(4): 294-8, 2000.
Article in English | MEDLINE | ID: mdl-10961361

ABSTRACT

It is known that either chronic glucocorticoid administration or endogenous hypercortisolism frequently induce an hypercoagulable condition. Since little is known about the evaluation of markers of haemostatic and fibrinolytic systems in other adrenal disorders, we studied plasminogen activator inhibitor (PAI-1), tissue-plasminogen activator (t-PA), fibrinogen and von Willebrand factor antigen (vWF-Ag) levels in 11 patients with Cushing's syndrome and in 12 patients with adrenal incidentaloma. In patients with Cushing's syndrome mean PAI-1, t-PA and vWF-Ag levels did not significantly differ from those found in 50 age- and sex-matched controls, while mean fibrinogen levels were significantly higher in patients (337.0+/-39.1 mg/dl) than in normal subjects (278.9+/-8.4 mg/dl). Patients with adrenal incidentaloma showed PAI-1, t-PA and vWF-Ag mean levels superimposable to those in controls, while fibrinogen (319.7+/-27.9 mg/dl) was slightly, although not significantly, higher than in normals. Considering the limits of normal values (as mean+/-2 SD) obtained in the control group, high PAI-1 levels were found in 2 patients with Cushing's syndrome and in 3 patients with incidentaloma. An elevation of fibrinogen levels was found in 3 patients with Cushing's syndrome and in 3 with incidentaloma. Increased vWF-Ag levels were found only in 1 patient with Cushing's syndrome. An increased t-PA level was occasionally observed only in the patient with adrenal carcinoma. On the whole, an alteration of at least one of haemostatic and fibrinolytic parameters was detected in 55% of the patients with Cushing's syndrome and in 42% of those with adrenal incidentaloma. In conclusion, early alterations of coagulation and fibrinolytic systems may be found in some patients with adrenal disorders, thus suggesting the opportunity of an accurate follow-up in order to identify possible risk factors for cardiovascular disease and thromboembolism.


Subject(s)
Adrenal Gland Neoplasms/blood , Cushing Syndrome/blood , Fibrinolysis , Hemostasis , Adult , Aged , Biomarkers , Female , Humans , Male , Middle Aged , Reference Values
10.
J Endocrinol Invest ; 23(3): 145-50, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10803470

ABSTRACT

Patients with active Cushing's syndrome have an increased thrombotic tendency. We chose to reassess the mechanism underlying the thrombophilic state associated with this clinical condition using sensitive markers of coagulation and fibrinolysis activation in 17 patients with active disease. The results were compared with those obtained in 12 Cushing's patients successfully treated by surgery and in 20 normal individuals. The general pattern of results in patients with active disease was the finding of increased levels of von Willebrand factor (VWF: Ag), a marker of enhanced metabolic function of endothelial cells (VWF:Ag 181 +/- 42 vs 110 +/- 43, p<0.001 in normal subjects), accompanied by signs of heightened thrombin and plasmin generation, expressed by high levels of thrombin-antithrombin (TAT 5.59+/-3.6 vs 3.06+/-0.92 ng/ml in controls, p<0.01) and plasmin-antiplasmin complexes (PAP 407+/-176 vs 245+/-67 ng/ml in controls, p<0.01). VWF:Ag and TAT values were significantly higher in hypertensive than in normotensive patients with active disease (205+/-40 vs 155+/-26 U/dl, p<0.05 and 7.49+/-3.7 vs 3.45+/-1.8, p<0.01, respectively). Plasma levels of plasminogen activator inhibitor type 1 were higher, though not to a statistically significant extent, in patients with active disease compared to controls (12.8+/-12.3 vs 5.6+/-7.4 IU/ml, NS) and positively correlated with body mass index (r=0.66, p<0.01). After surgical control of Cushing's syndrome, there was a partial or complete reversal of the abnormalities to values similar to those found in normal individuals. Our data suggest that the thrombophilic state present in patients with active Cushing's syndrome is related to an enhanced metabolic function of endothelial cells; this in turn may be caused by an heightened production of thrombin with secondary hyperfibrinolysis. Primary prophylaxis with anticoagulants is recommended in these patients when they are exposed to a thrombophilic condition such as surgery.


Subject(s)
Blood Coagulation/physiology , Cushing Syndrome/blood , Fibrinolysis/physiology , Adolescent , Adult , Biomarkers , Blood Cell Count , Blood Coagulation Tests , Child , Cushing Syndrome/surgery , Female , Hemostasis/physiology , Humans , Hydrocortisone/urine , Male , Recurrence
11.
Clin Exp Immunol ; 115(3): 526-33, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10193429

ABSTRACT

beta-Amyloid (beta-A) accumulates in the brain of patients with Alzheimer's disease (AD) and is presumably involved in the pathogenesis of this disease, on account of its neurotoxicity and complement-activating ability. Although assembly of beta-A in particular aggregates seems to be crucial, soluble non-fibrillar beta-A may also be involved. Non-fibrillar beta-A does not bind C1q, so we investigated alternative mechanisms of beta-A-dependent complement activation in vitro. On incubation with normal human plasma, non-fibrillar beta-A 1-42, and truncated peptide 1-28, induced dose-dependent activation of C1s and C4, sparing C3, as assessed by densitometric analysis of immunostained membrane after SDS-PAGE and Western blotting. The mechanism of C4 activation was not dependent on C1q, because non-fibrillar beta-A can still activate C1s and C4 in plasma genetically deficient in C1q (C1qd). In Factor XII-deficient plasma (F.XIId) the amount of cleaved C4 was about 5-10% less that in C1qd and in normal EDTA plasma; the reconstitution of F.XIId plasma with physiologic concentrations of F.XII resulted in an increased (8-15%) beta-A-dependent cleavage of C4. Thus our results indicate that the C1q-independent activation of C1 and C4 can be partially mediated by the activation products of contact system. Since the activation of contact system and of C4 leads to generation of several humoral inflammatory peptides, non-fibrillar beta-A might play a role in initiating the early inflammatory reactions leading to a multistep cascade contributing to neuronal and clinical dysfunction of AD brain.


Subject(s)
Alzheimer Disease/immunology , Amyloid beta-Peptides/immunology , Complement C1q/metabolism , Complement Pathway, Classical , Alzheimer Disease/blood , Alzheimer Disease/etiology , Amyloid beta-Peptides/ultrastructure , Complement C1s/metabolism , Factor XII Deficiency/immunology , Fibrinolysin/antagonists & inhibitors , Fibrinolysin/biosynthesis , Fibrinolysis , Humans , In Vitro Techniques , Microscopy, Electron , Peptide Fragments/immunology , Peptide Fragments/ultrastructure
12.
Arterioscler Thromb Vasc Biol ; 17(7): 1325-30, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9261263

ABSTRACT

Intravenous heparin, a fundamental therapy in the treatment of patients with acute coronary syndromes, acts by inhibiting thrombin and activated factors X, IX, XI, and XII. It has also been demonstrated that heparin reduces plasma fibrinopeptide A, a marker of thrombin activity, but it is unknown whether it decreases prothrombin fragment 1+2, an indirect marker of thrombin generation. We measured the plasma levels of prothrombin fragment 1+2, fibrinopeptide A, and antithrombin III in 64 consecutive patients with unstable angina or myocardial infarction receiving intravenous heparin. Blood samples were obtained at baseline (before any treatment) and then at 90 minutes and 24 and 48 hours after the administration of an intravenous bolus of heparin (5000 IU) followed by a continuous infusion of 1000 IU per hour to maintain activated partial thromboplastin time at more than double its baseline levels. In comparison with baseline, there was a significant decrease in fibrinopeptide A at 90 minutes and at 24 and 48 hours (baseline, 2.3 nmol/L; 90 minutes, 1.15 nmol/L; 24 hours, 1.4 nmol/L; 48 hours, 1.2 nmol/L; P < .0001) but no change in prothrombin fragment 1+2 levels (baseline, 1.27 nmol/L; 90 minutes, 1.3 nmol/L; 24 hours, 1.33 nmol/L; 48 hours, 1.29 nmol/L; P = NS). Antithrombin III activity decreased at 24 and 48 hours (baseline, 108%; 24 hours, 97%; 48 hours, 95%; P < .0001). Hence, in patients with acute coronary syndromes, intravenous heparin at a dose reaching an activated partial thromboplastin time that adequately suppresses thrombin activity does not suppress increased thrombin generation.


Subject(s)
Angina, Unstable/blood , Heparin/administration & dosage , Myocardial Infarction/blood , Thrombin/metabolism , Acute Disease , Antithrombin III/metabolism , Biomarkers , Blood Coagulation , Enzyme Activation , Female , Fibrinopeptide A/metabolism , Humans , Injections, Intravenous , Male , Time Factors
13.
Blood ; 89(9): 3213-8, 1997 May 01.
Article in English | MEDLINE | ID: mdl-9129025

ABSTRACT

Activation of the contact and complement systems in C1-inhibitor deficiencies is thought to contribute to the pathogenesis of angioedema attacks by releasing kinins. Trigger stimuli of attacks may also activate coagulation. This is particularly important because experimental data suggest that thrombin, the main enzyme of the coagulation cascade, increases vascular permeability and can thus influence edema formation. We have studied 19 patients with hereditary angioedema (HAE) during remission, 5 HAE patients during acute attacks, and 6 patients with acquired angioedema (AAE) during remission and during seven attacks. Thirty normal subjects, matched for sex and age, served as controls. Generation of thrombin was measured by enzyme-linked immunosorbent assay (ELISA) as plasma levels of the prothrombin fragment 1 + 2 (F1 + 2); the initiators of the tissue factor and contact coagulation pathways were investigated by measuring plasma levels of activated factor VII (FVIIa) coagulometrically and activated factor XII (FXIIa) by ELISA. Cleavage of high molecular weight kininogen (HK) was evaluated by immunoblotting analysis. F1 + 2 was slightly increased during remission and further significantly increased during attacks in both HAE (P = .0115) and AAE. FVIIa and FXIIa, normal during remission, increased strikingly during attacks in both HAE (P = .0022 and P = .0044) and AAE. During remission, cleaved HK was normal in HAE and high in AAE; during attacks it increased in HAE (P = .0008) and remained elevated in AAE. Our data indicate that in C1-inhibitor deficient patients there is increased generation of thrombin during attacks, with signs of activation of both the contact and tissue factor coagulation pathways. In conclusion, C1-inhibitor deficiency, whether hereditary or acquired, has demonstrable activation of the coagulation and kinin-forming cascades during attacks and that thrombin should be considered a possible contributing factor in the pathogenesis of edema in HAE and AAE.


Subject(s)
Angioedema/blood , Blood Coagulation Factors/analysis , Blood Coagulation , Complement C1 Inactivator Proteins/deficiency , Complement C4/analysis , Adult , Aged , Angioedema/genetics , Complement C1 Inactivator Proteins/analysis , Enzyme-Linked Immunosorbent Assay , Factor VIIa/analysis , Factor XII/analysis , Female , Humans , Kininogens/blood , Male , Middle Aged , Peptide Fragments/analysis , Protein Precursors/analysis , Prothrombin/analysis , Reference Values , Thrombin/analysis
14.
Eur J Clin Nutr ; 50(8): 535-44, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8863014

ABSTRACT

OBJECTIVE: To evaluate the effect of moderate consumption of red wine on composition of platelet phospholipids, discriminating the effect of alcohol from that of non-alcoholic components. DESIGN: A randomised crossover study. SETTING: The Department of Food Science and Technology, University of Milan. SUBJECTS: Eleven healthy male volunteers who were moderate drinkers. INTERVENTIONS: For three periods of 4 weeks, subjects drank three different beverages [320 ml of red wine (providing 30 g/day of alcohol), 30 g/day of alcohol diluted in 320 ml of clear fruit juice or 320 ml of dealcoholised red wine] during the two main meals. Each treatment was preceded by a period of 4 weeks of complete withdrawal from any alcoholic beverage. At the end of each period the fatty acid composition of individual phospholipids was determined on isolated platelets. RESULTS: Consumption for a period of 4 weeks of non-alcoholic components either from 320 ml of red wine or from the same amount of dealcoholised red wine resulted in similar increases in polyunsaturated fatty acids in all phospholipid fractions of platelet, with the exception of sphingomyelin. No differences were detected when we compared the composition of phospholipids at the end of red wine and alcohol treatments with findings at the end of dealcoholised treatment and abstinence. CONCLUSIONS: The increase of polyunsaturated fatty acids in platelet phospholipids due to the non-alcoholic components of red wine suggests an antioxidant effect that could be relevant in justifying the protective effect of red wine shown in epidemiological studies.


Subject(s)
Alcohol Drinking/metabolism , Blood Platelets/chemistry , Fatty Acids, Unsaturated/blood , Fatty Acids/blood , Phospholipids/blood , Wine , Adult , Antioxidants , Blood Platelets/metabolism , Cohort Studies , Cross-Over Studies , Fatty Acids, Unsaturated/metabolism , Humans , Male , Middle Aged , Phosphatidylcholines/chemistry , Phosphatidylethanolamines/chemistry , Phosphatidylinositols/chemistry , Phosphatidylserines/chemistry , Phospholipids/chemistry , Sphingomyelins/chemistry
15.
Thromb Haemost ; 75(5): 703-5, 1996 May.
Article in English | MEDLINE | ID: mdl-8725708

ABSTRACT

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, prothrombin fragment 1 + 2 (F1+2) and thrombin-antithrombin complexes (TAT) were measured. High levels of F1+2 and TAT were found in 32% and 23% 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 F1+2 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 F1+2 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.


Subject(s)
Anticoagulants/pharmacology , Factor V/genetics , Protein C/pharmacology , Thrombin/analysis , Thrombosis/blood , Adolescent , Adult , Aged , Child , Drug Resistance/genetics , Heterozygote , Homozygote , Humans , Middle Aged , Prothrombin/analysis , Thrombin/metabolism , Thrombosis/etiology , Thrombosis/genetics
16.
Thromb Haemost ; 75(2): 216-8, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8815562

ABSTRACT

Since it has not been established to what extent abnormalities of hemostasis contribute to the occurrence and development of dementia, selected measurements of coagulation and fibrinolysis were obtained in elderly patients with Alzheimer's disease (n = 22) or vascular dementia (n = 29), compared with healthy individuals in the same age range (n = 61). Hemostasis abnormalities were more frequent and marked in vascular dementia, being expressed as significant increases of plasminogen activator inhibitor type 1, von Willebrand factor, D-dimer and activated factor VII. However, some hemostasis measurements (von Willebrand factor, activated factor VII) were abnormally high also in the patients with Alzheimer's disease, a condition in which vascular damage is not considered to play a major pathogenetic role. It could not be established in this study whether or not these hemostatic abnormalities play a casual role in the pathogenesis of dementia, or whether they are secondary to inflammation and chronic vascular disease. Nevertheless, their presence may contribute to aggravating vascular disease.


Subject(s)
Alzheimer Disease/blood , Blood Coagulation Disorders/complications , Blood Proteins/analysis , Dementia, Vascular/blood , Aged , Alzheimer Disease/complications , Blood Coagulation , Blood Coagulation Disorders/blood , Blood Coagulation Factors/analysis , Dementia, Vascular/complications , Female , Fibrin Fibrinogen Degradation Products/analysis , Fibrinogen/analysis , Fibrinolysis , Fibrinopeptide A/analysis , Humans , Male , Peptide Fragments/analysis , Prothrombin/analysis
17.
Thromb Res ; 81(3): 345-52, 1996 Feb 01.
Article in English | MEDLINE | ID: mdl-8928092

ABSTRACT

The purpose of this study was to evaluate whether or not, using sensitive analytical methods for the measurement of coagulation and fibrinolysis enzyme activity, there was a hypercoagulable state in patients with melanoma, and whether differences existed between those with or without metastases. Seventy-one patients were studied, 45 with localized tumors (stages Ia and Ib) and 26 with metastases (stages II-IV). Plasma level of activated factor VII, prothrombin fragment 1 + 2, thrombin-antithrombin complex, fibrinopeptide A, plasmin-antiplasmin complex and D-dimer were much higher in the whole group of 71 patients than in 45 controls with benign nevi. However, when melanoma patients with or without metastases were compared, there were smaller differences, with only thrombin-antithrombin complex, plasmin-antiplasmin and D-dimer significantly higher in metastatic melanoma. These results indicate that in patients carrying a tumor endowed with high procoagulant activity in vitro, there is a laboratory picture of hypercoagulability with secondary hyperfibrinolysis in vivo. However, differences between patients with localized and metastatic tumors for markers of hypercoagulability are not striking, in spite of the fact that metastatic cells support greater coagulant activity than primary cells in vitro.


Subject(s)
Blood Coagulation Disorders/etiology , Fibrinolysis/physiology , Melanoma/blood , Adolescent , Adult , Aged , Blood Coagulation Disorders/enzymology , Case-Control Studies , Female , Humans , Male , Melanoma/complications , Melanoma/secondary , Middle Aged , Sensitivity and Specificity
18.
Blood ; 85(11): 3144-9, 1995 Jun 01.
Article in English | MEDLINE | ID: mdl-7756646

ABSTRACT

With advancing age, an increasing number of healthy individuals have laboratory signs of heightened coagulation enzyme activity. Such biochemical hypercoagulability might be the basis of either the increased thrombotic tendency occurring with age or a harmless manifestation of this process. To see whether these alterations are also present in the very elderly who had aged successfully, 25 healthy centenarians were studied and results of coagulation and fibrinolysis measurements were compared with those obtained in two control groups of healthy adults, 25 ranging in age from 18 to 50 years and 25 from 51 to 69 years. Older controls had, in general, slightly higher values of several coagulation and fibrinolysis measurements than younger controls. Centenarians had striking signs of heightened coagulation enzyme activity, as assessed directly by measuring activated factor VII in plasma (P < .01, compared with either control group) or indirectly by measuring the plasma levels of the activation peptides of prothrombin, factor IX, factor X, and thrombin-antithrombin complexes (all P < .001). Heightened coagulation enzyme activity was accompanied by signs of enhanced formation of fibrin (high fibrinopeptide A, P < .001) and secondary hyperfibrinolysis (high D-dimer and plasmin-antiplasmin complex, P < .001). Plasma concentrations of fibrinogen and factor VIII were higher than in controls, whereas other coagulation factors were not elevated. In conclusion, this study shows the very elderly do not escape the state of hypercoagulability associated with aging, but that this phenomenon is compatible with health and longevity. Hence, high plasma levels of the coagulation activation markers in older populations do not necessarily mirror a high risk of arterial or venous thrombosis.


Subject(s)
Aged, 80 and over , Aging/physiology , Blood Coagulation/physiology , Adolescent , Adult , Aged , Blood Coagulation Factors/analysis , Disease Susceptibility , Enzyme Activation , Female , Fibrin/biosynthesis , Fibrinolysis , Humans , Male , Middle Aged , Reference Values , Thromboembolism/etiology
19.
Thromb Haemost ; 71(5): 605-8, 1994 May.
Article in English | MEDLINE | ID: mdl-8091388

ABSTRACT

We compared F 1 + 2 results obtained with two commercial ELISA methods (Behring and Baxter) assaying the same plasma samples. There was little correlation between the results of the two methods, as shown by the low correlation coefficient (r = 0.50) and by low percentage of concordant classification (normal or abnormal) of the samples (24%). Such poor correlation is probably due to the different anticoagulants suggested, because correlation improved when both methods were carried out in plasmas collected with the same anticoagulant. However, the Baxter method still gave significantly lower F 1 + 2 values than the Behring method. Assuming that this difference is due to the use of standards with different F 1 + 2 concentrations, the standards from Behring and Baxter were evaluated by both methods. Parallel dose-response curves were obtained when the standards were run by the Behring method but not by the Baxter method, indicating that the two standards are qualitatively different. This study demonstrates that the two F 1 + 2 methods give different values for the same samples and that these values are poorly correlated. Standardization of the F 1 + 2 assays cannot be achieved easily simply by using a common standard and the use of different anticoagulants appears to be the main reason for poor standardization.


Subject(s)
Anticoagulants/pharmacology , Enzyme-Linked Immunosorbent Assay/methods , Peptide Fragments/analysis , Prothrombin/analysis , Adolescent , Adult , Autoimmune Diseases/blood , Female , Humans , Male , Melanoma/blood , Middle Aged , Peptide Fragments/drug effects , Prothrombin/drug effects , Reference Standards , Reference Values , Reproducibility of Results
20.
Br J Haematol ; 84(4): 670-4, 1993 Aug.
Article in English | MEDLINE | ID: mdl-8217826

ABSTRACT

Hypercoagulability can be defined as a condition of procoagulant imbalance due to heightened enzymatic activation of coagulation zymogens, but with no laboratory evidence of fibrin deposition nor clinical signs of thrombosis. The imbalance can be detected by measuring the plasma levels of prothrombin fragment 1 + 2 (F1 + 2), fibrinopeptide A (FPA) and thrombin-antithrombin III (TAT) complexes. The aims of this study were to establish the frequency of existence and biochemical pattern of hypercoagulability in patients with cancer and autoimmune disorders, clinical conditions associated with an increased risk of thrombosis, and to ascertain the most sensitive method for its diagnosis. In approximately one-fourth of the patients hypercoagulability was identified by finding high levels of FPA F1 + 2 or TAT unaccompanied by signs of fibrin deposition (expressed by normal levels of D-dimer). In a smaller proportion of patients (approximately 10%), the concomitant presence of high levels of D-dimer indicated that the activation of the coagulation cascade had gone beyond the stage of heightened enzymatic activity to the point of cross-linked fibrin deposition. Of the markers used to detect hypercoagulability. FPA seems to be the most sensitive, being significantly increased in all clinical conditions studied.


Subject(s)
Autoimmune Diseases/blood , Blood Coagulation/physiology , Lupus Erythematosus, Systemic/blood , Melanoma/blood , Skin Neoplasms/blood , Adolescent , Adult , Antithrombin III/analysis , Biomarkers/blood , Female , Fibrin Fibrinogen Degradation Products/analysis , Fibrinopeptide A/analysis , Humans , Male , Middle Aged , Peptide Hydrolases/analysis , Prothrombin/analysis
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