| 1. |
- Eriksson, Andreas C, et al.
(författare)
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Adhesion of human platelets to albumin is synergistically increased by lysophosphatidic acid and adrenaline in a donor-dependent fashion
- 2006
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Ingår i: Blood Coagulation and Fibrinolysis. - : Ovid Technologies (Wolters Kluwer Health). - 0957-5235 .- 1473-5733. ; 17:5, s. 359-368
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Tidskriftsartikel (refereegranskat)abstract
- Lysophosphatidic acid (LPA) and adrenaline are weak platelet activators considered important for thrombus formation, and were previously shown to synergistically increase platelet aggregation. Here we investigate synergistic activation by LPA and adrenaline when measuring platelet adhesion. Platelet-rich plasma from healthy blood donors together with adrenaline and/or LPA were added to protein-coated microplates. Platelets were allowed to adhere and the amount of adhesion detected enzymatically. The LPA and adrenaline combination induced a synergistic increase of platelet adhesion to a normally non-adhesive albumin surface. The degree of synergy varied markedly between individuals; these variations could not be explained by age, gender, blood type or different amounts of platelets, oxidized low-density lipoprotein, insulin or glucose in plasma. There was a trend indicating increased synergistic effect for platelets sensitive to adrenaline stimulation. The synergistic effect was blocked by the α2-adrenoceptor antagonist yohimbine and inhibited by the ADP scavenger system creatine phosphate/creatine phosphokinase and antibodies against αIIbβ3. Furthermore, platelets adhering to albumin after adrenaline and LPA treatment expressed P-selectin. In conclusion, LPA and adrenaline act synergistically to increase αIIbβ3-mediated platelet adhesion to albumin, dependent on α2-adrenoceptor signalling and platelet secretion. We also confirm that synergistic platelet activation achieved with LPA and adrenaline is highly donor dependent.
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| 2. |
- Eriksson, Maria A, 1965-, et al.
(författare)
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Sex-related differences in the associations between hyperleptinemia, insulin resistance and dysfibrinolysis
- 2008
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Ingår i: Blood Coagulation and Fibrinolysis. - : Lippincott Williams & Wilkins. - 1473-5733 .- 0957-5235. ; 19:7, s. 625-632
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Tidskriftsartikel (refereegranskat)abstract
- The adipocyte-derived hormone leptin is associated with insulin resistance and reduced fibrinolytic status - or dysfibrinolysis - in humans. As leptin associates differentially to the development of cardiovascular disease and diabetes in men and women, we hypothesized that leptin and insulin sensitivity are related to dysfibrinolysis in a sex-dependent manner. Thirty-two men and 40 women were recruited from the Monitoring of trends and determinants in Cardiovascular disease (MONICA) population sample, representing the highest and lowest quartiles of fasting insulin levels. Lipids, fibrinolytic status [plasminogen activator inhibitor 1 (PAI-1) activity, tissue plasminogen activator (tPA) mass and activity, and tPA-PAI complex], leptin, testosterone and sex-hormone-binding globulin were measured. Insulin sensitivity was estimated using the euglycaemic clamp technique. Body composition was determined by bioimpedance. Determinants for circulating levels of fibrinolytic factors were explored in a multivariate linear regression analysis. Levels of fibrinolytic variables and estimated insulin sensitivity did not differ between men and women. Leptin was independently associated with reduced fibrinolytic status high PAI-1 activity, low tPA activity, high tPA mass, and high tPA-PAI complex) in men (P<0.001-0.002). In women, fat mass and/or insulin sensitivity were related to these factors (P<0.001-0.03), and leptin only to reduced tPA activity (P = 0.002). Hyperleptinemia, dysfibrinolysis, insulin sensitivity and androgenicity associate differentially in men and women. Blood Coagul Fibrinolysis 19:625-632 (C) 2008 Wolters Kluwer Health | Lippincott Williams & Wilkins.
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| 3. |
- Jennersjö, Cecilia, 1963-, et al.
(författare)
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Normal D-dimer concentration is a common finding in symptomatic outpatients with distal deep vein thrombosis
- 2005
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Ingår i: Blood Coagulation and Fibrinolysis. - 0957-5235 .- 1473-5733. ; 16:7, s. 517-523
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Tidskriftsartikel (refereegranskat)abstract
- The D-dimer analysis has been shown to have a high sensitivity and a high negative predictive value for the exclusion of deep vein thrombosis (DVT). However, most D-dimer studies, including recent clinical management studies, are performed without examination of the calf veins and/or performed on patient populations with a predominance of proximal DVT. The purpose of this study was to evaluate the diagnostic performance of the D-dimer test in a population with a suspected high incidence of distal DVT. In the present study, 393 outpatients with clinically suspected symptomatic DVT of the lower extremities were examined with whole-leg duplex ultrasonography. The D-dimer analysis was performed using an automated micro-latex assay (Tina-quant). A total of 137 of 393 patients had a proven DVT, with the majority presenting with distal DVT (59%). Twenty-eight out of 81 patients with distal DVT had a normal D-dimer, compared with two of 56 patients with proximal DVT. The sensitivity for distal DVT was only 65% compared with 96% for proximal DVT, the negative predictive values were 84 and 99%, respectively. In conclusion, the prevalence of distal DVT in a study population seems to have a great impact on the diagnostic performance of the D-dimer analysis. The study results also show that normal D-dimer levels do not exclude distal DVT in outpatients, instead, it can be hypothesized that normal D-dimer levels exclude DVT that require treatment, as indicated by the good outcome in recent management studies. © 2005 Lippincott Williams & Wilkins.
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| 4. |
- Osman, Abdimajid, et al.
(författare)
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Plasma S/R ratio of warfarin co-varies with VKORC1 haplotype
- 2007
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Ingår i: Blood Coagulation and Fibrinolysis. - 0957-5235 .- 1473-5733. ; 18:3, s. 293-296
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Tidskriftsartikel (refereegranskat)abstract
- We recently reported that the low-dose VKORC1*2 haplotype is an important genetic determinant for warfarin dose requirement and is associated with difficulties to attain stable therapeutic prothrombin time-International Normalized Ratio in patients undergoing anticoagulation therapy. The aim of this study was to investigate whether patients with VKORC1*2 compared with patients carrying high-dose haplotypes VKORC1*3 or VKORC1*4 had different warfarin S/R ratios in their plasma, and whether that was related to CYP2C9 variants CYP2C9*2 and CYP2C9*3 or other factors. Samples from patients previously haplotyped for VKORC1 and measured for plasma warfarin concentration were genotyped for the CYP2C9 variants CYP2C9*2 and CYP2C9*3. Nonparametric statistical analysis was performed to elucidate whether there was any significant difference in the warfarin S/R ratio between the two patient groups. Our result shows that there is a significant difference (P < 0.01) in warfarin S/R ratios between VKORC1*2 and VKORC1*3 or VKORC1*4 patients. This difference did not originate from CYP2C9 variants CYP2C9*2 and CYP2C9*3. We speculate that VKORC1 haplotypes possibly are linked to some unidentified factors involved in the metabolic clearance of warfarin enantiomers. Dose-dependent variations in (S)-warfarin and (R)-warfarin clearance in these patients can also be a probable explanation for the difference in warfarin S/R ratios.
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| 5. |
- Ramström, Sofia, 1973-
(författare)
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Clotting time analysis of citrated blood samples is strongly affected by the tube used for blood sampling
- 2005
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Ingår i: Blood Coagulation and Fibrinolysis. - 0957-5235 .- 1473-5733. ; 16:6, s. 447-452
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Tidskriftsartikel (refereegranskat)abstract
- Our aim was to establish whether differences in clotting times for recalcified blood and plasma samples might be explained by the use of different blood collection tubes. Samples obtained from different plastic vacuum tubes were recalcified and clotting times determined by free oscillation rheometry. The clotting times for blood collected in Vacutainer (Becton Dickinson, Rutherford, New Jersey, USA) or Vacuette (Greiner Bio-One, Kremsmünster, Austria) tubes decreased with time, with maximal effect after 30 min. Blood from Monovette (Sarstedt, Nümbrecht, Germany) tubes displayed longer clotting times, which did not decrease with time. Clotting times for plasma prepared after 1 h storage in Vacutainer or Vacuette tubes were unaffected by subsequent addition of corn trypsin inhibitor to inhibit factor XIIa, although an antibody against factor XI prolonged the clotting time markedly. In Monovette plasma, both corn trypsin inhibitor and anti-factor XI effectively prolonged the clotting time. When corn trypsin inhibitor or anti-factor XI was added to the tubes before blood collection, but both additions clearly prolonged the clotting times in all types of tubes, even though corn trypsin inhibitor was less effective in whole blood. Antibodies against human tissue factor did not affect the clotting times. The amounts of platelet or leukocyte microparticles in plasma were low and similar in all tubes. This indicates that blood collection in Vacutainer or Vacuette tubes induces a rapid activation of factor XII and factor XI.
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| 6. |
- Thøgersen, Anna M., et al.
(författare)
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Changes in plasma C-reactive protein and hemostatic factors prior to and after a first myocardial infarction with a median follow-up time of 8 years
- 2009
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Ingår i: Blood Coagulation and Fibrinolysis. - 0957-5235 .- 1473-5733. ; 20:5, s. 340-346
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to determine whether a first myocardial infarction leads to increased plasma levels of hemostatic factors and high sensitive C-reactive protein (hs-CRP) and whether the association between theses biomarkers and myocardial infarction was greater at follow-up compared with baseline. Of more than 36,000 persons screened in northern Sweden, 78 developed a first myocardial infarction (on average 18 months after sampling) in a population-based, prospective, nested patient-referent study. Fifty of these had participated in a follow-up health survey (on average 8 and a half years between surveys) and were sex-matched and age-matched with 56 referents. The mean increases in hs-CRP, tissue plasminogen activator (tPA) mass, plasminogen activator inhibitor-1 mass, and tPA/plasminogen activator inhibitor-1 complex concentration and von Willebrand factor among patients and referents were comparable during follow-up. Conditional logistic regression indicated that hs-CRP was not significantly associated with first myocardial infarction in a univariate analysis, whereas high plasma levels of tPA and creatinine were significantly associated with outcome at baseline and follow-up. tPA/plasminogen activator inhibitor-1 complex was not superior to tPA as a risk marker in this study. A first myocardial infarction did not in this study induce significantly different changes in plasma levels of hs-CRP and hemostatic factors among patients compared with referents during follow-up.
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| 7. |
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| 8. |
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| 9. |
- Berntorp, Erik, et al.
(författare)
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Long-term prophylaxis in von Willebrand disease
- 2005
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Ingår i: Blood Coagulation and Fibrinolysis. - 1473-5733. ; 16:Suppl 1, s. 23-26
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Tidskriftsartikel (refereegranskat)abstract
- The majority of patients with von Willebrand disease (VWD) have a mild bleeding tendency that primarily involves mucosal bleeding. Some patients with the disorder, however, have severe episodes of mucosal or joint bleeding that can hamper daily activities and lead to significant joint impairment. Experience in the setting of severe hemophilia has shown the feasibility and benefits of prophylactic treatment to prevent bleeding and development of arthropathy. This approach also needs to be evaluated in patients with VWD who require repetitive treatment for bleeding episodes. Data from a series of 35 patients (with VWD types 3, 2A, 2B, and 1) who have received long-term prophylaxis at Malmo University Hospital and Karolinska University Hospital in Stockholm, Sweden, have demonstrated a substantial reduction of bleeding episodes since initiation of treatment. Patients who began prophylaxis at a young age (younger than 5 years) to prevent nose and mouth bleeds have had no joint bleeds and have no clinical signs of arthropathy. Treatment has been safe, with no cases of thrombosis, and no viral transmission among patients who received virus-aftenuated von Willebrand factor-containing factor VIII concentrate. These data thus suggest that long-term prophylaxis is warranted in the majority of patients with type 3 VWD and in other subtypes with severe bleeding tendencies, and that such an approach may help in the avoidance of joint disease if started early. More clinical data and controlled trials are needed in order to formulate recommendations for prophylaxis in patients with VWD.
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| 10. |
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