Abstract:
:The effect of shear rate and fibrinogen concentration on adenosine diphosphate-induced aggregation of suspensions of washed human platelets in Poiseuille flow at 23 degrees C was studied using a previously described double infusion technique and resistive particle counter size analysis. Using suspensions of multiple-centrifuged and -washed cells in Tyrodes-albumin [3 x 10(5) microliters-1; (17)] with [fibrinogen] from 0 to 1.2 microM, the rate and extent of aggregation with 0.7 microM ADP in Tyrodes-albumin were measured over a range of mean transit times from 0.2 to 43 s, and at mean tube shear rates, G, = 41.9, 335 and 1,335 s-1. As measured by the decrease in singlet concentration, aggregation at 1.2 microM fibrinogen increased with increasing G up to 1,335 s-1, in contrast to that previously reported in citrated plasma, in which aggregation reached a maximum at G = 335 s-1. Without added fibrinogen, there was no aggregation at G = 41.9 s-1; at G = 335 s-1, there was significant aggregation but with an initial lag time, aggregation increasing further at G = 1,335 s-1. Without added fibrinogen, aggregation was abolished at all G upon incubation with the hexapeptide GRGDSP, but was almost unaffected by addition of an F(ab')2 fragment of an antibody to human fibrinogen. Aggregation in the absence of added fibrinogen was also observed at 37 degrees C. The activation of the multiple-washed platelets was tested using flow cytometry with the fluorescently labelled monoclonal antibodies FITC-PAC1 and FITC-9F9. It was shown that 57% of single cells in unactivated PRT expressed maximal GPIIb-IIIa fibrinogen receptors (MoAb PAC1) and 54% expressed pre-bound fibrinogen (MoAb 9F9), with further increases on ADP activation. However, incubation with GRGDSP and the F(ab')2 fragment did not inhibit the prebound fibrinogen. Moreover, relatively unactivated cells (8% expressing receptor, 14% prebound fibrinogen), prepared from acidified cPRP by single centrifugation with 50 nM of the stable prostacyclin derivative, ZK 36,374, and resuspension in Tyrodes-albumin at 5 x 10(4) microliters-1, aggregated with 2 and 5 microM ADP at G = 335 and 1,335 s-1 in the absence of added fibrinogen. We therefore postulate that a protein such as von Willebrand factor, secreted during platelet isolation or in flow at sufficiently high shear rates, may yield the observed shear-rate dependent aggregation without fibrinogen.
journal_name
Thromb Haemostjournal_title
Thrombosis and haemostasisauthors
Goldsmith HL,Frojmovic MM,Braovac S,McIntosh F,Wong Tsubject
Has Abstractpub_date
1994-01-01 00:00:00pages
78-90issue
1eissn
0340-6245issn
2567-689Xjournal_volume
71pub_type
杂志文章abstract::Dabigatran is an oral, reversible thrombin inhibitor that has shown promising results in large clinical trials. Laboratory monitoring is not needed but the effects on common coagulation assays are incompletely known. Dabigatran was added to plasma from healthy subjects in the concentration range 0-1,000 μg/l and analy...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:10.1160/TH10-06-0342
更新日期:2011-02-01 00:00:00
abstract::The endocannabinoid anandamide (AEA) has many neurovascular activities. However, it is not yet clear how AEA can be metabolized at the neurovascular interface, and how it can move through the vascular and the cerebral compartments. The results reported in this article show that isolated bovine brain microvessels, an e...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:2006-01-01 00:00:00
abstract::ADP or thrombin caused a transient change in creatine phosphate (CP) content of rat platelets. At 25 degrees C the CP content decreased most 30 sec after the addition of ADP or thrombin and recovered thereafter. ATP or AMP was without effect. The rat platelets aggregated at 25 degrees C by ADP or thrombin, but the cha...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:1979-08-31 00:00:00
abstract::We have previously suggested that the human homologue of the Drosophila transient receptor potential protein, TRPC1, is involved in conducting store-operated Ca2+ entry (SOCE) in human platelets since an antibody raised against the pore-forming region of TRPC1 inhibited SOCE. Here we have investigated plasma membrane ...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:10.1160/TH05-06-0391
更新日期:2005-10-01 00:00:00
abstract::Heparin cofactor II (HC II) is a heparin-dependent inhibitor of thrombin, distinct from antithrombin III (AT III). This study was designed to evaluate its metabolism in healthy subjects. Purified HC II was labelled with 125I by the lactoperoxidase-glucose oxidase technique. The biological activity of the HC II was unc...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:1985-10-30 00:00:00
abstract::The effect of a basic synthetic peptide, representing the C-terminal region of tissue factor pathway inhibitor (TFPI - Lys254 - Met276), as well as that of the whole protein, on the activity of lipoprotein lipase (LPL) is described. The activity of bovine LPL was measured by chromogenic assay using a water-soluble chr...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:1999-12-01 00:00:00
abstract::In patients with deep vein thrombosis (DVT), the factors which predispose to concomitant symptomatic pulmonary embolism (PE) have remained uncertain. From a prospective cohort of 5,451 consecutive patients with ultrasound-confirmed DVT, we analyzed 4,211 patients with a known status for presence (n=639) or absence (n=...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:10.1160/TH04-09-0587
更新日期:2005-03-01 00:00:00
abstract::The administration of recombinant activated factor VII (rFVIIa) by continuous infusion has provided a safe and convenient alternative to bolus injections in haemophiliacs with inhibitors, but it has only been reported in a single case with congenital factor VII (FVII) deficiency. The results of 12 consecutive surgical...
journal_title:Thrombosis and haemostasis
pub_type: 临床试验,杂志文章,多中心研究
doi:10.1160/TH05-05-0342
更新日期:2005-12-01 00:00:00
abstract::Elucidation of the molecular defects responsible for antithrombin III deficiency is proceeding rapidly. In order that a record is kept of the new and duplicated mutations that are found, we have compiled a database that we plan to update annually. In this, the first report of the database, we list 6 antithrombin III l...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:1991-12-02 00:00:00
abstract::Examination of the entire von Willebrand factor (VWF) gene for mutations, particularly in types 1 and 3 von Willebrand disease (VWD) is becoming more widely practised. The sequence of the entire VWF gene will soon be compiled as a single sequence. For these reasons, a clearly defined nomenclature to use for numbering ...
journal_title:Thrombosis and haemostasis
pub_type: 指南,杂志文章
doi:
更新日期:2001-05-01 00:00:00
abstract::The cofactor tetrahydrobiopterin (BH4) is required for nitric oxide (NO) production by all nitric oxide synthase (NOS) enzymes and is a key regulator of cellular redox signalling. When BH4 levels become limiting NOS enzymes become 'uncoupled' and produce superoxide rather than NO. Endothelial cell BH4 is required for ...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章,评审
doi:10.1160/TH12-06-0424
更新日期:2012-11-01 00:00:00
abstract::Compared to second generation, the use of third generation oral contraceptives has been associated with an increased risk of venous thrombosis especially in women with the factor V Leiden mutation. To find an explanation for these risk differences we investigated the effects of desogestrel- and levonorgestrel-containi...
journal_title:Thrombosis and haemostasis
pub_type: 临床试验,杂志文章,随机对照试验
doi:
更新日期:2002-02-01 00:00:00
abstract::The Ig-ITIM superfamily member, PECAM-1 acts as a negative regulator of ITAM-signalling pathways in platelets involving GPVI/FcR gamma chain and Fc?RIIa. This negative feedback loop involves regulation of collagen and GPVI-dependent aggregation events, platelet-thrombus-growth on immobilised collagen under flow and Fc...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:2006-12-01 00:00:00
abstract::Peripheral vascular disease (PVD) is an indicator of diffuse atherosclerosis and is associated with a greatly increased incidence of coronary heart and cerebrovascular disease. Although several studies have assessed whether in vivo platelet activation takes place in patients with PVD, no data are available comparing d...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:1997-12-01 00:00:00
abstract::The synthetic peptide SFLLRNPNDKYEPF, identical in sequence to the new amino-terminus of the thrombin receptor generated following cleavage of thrombin, acts a thrombin receptor agonist/activating peptide (TRAP). In this study, Northern blot analysis showed that cultured human vascular smooth muscle cells (HVSMC) expr...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:1995-11-01 00:00:00
abstract::We have discovered a novel small-molecule (3-phosphinoylpropionic acid) inhibitor of activated thrombin activatable fibrinolysis inhibitor (TAFIa), BX 528, which had an IC (50) of 2 nM in an enzymatic assay and 50 nM in an in-vitro clot lysis assay, with 3,500- to 35,000-fold selectivity against other carboxypeptidase...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:2007-01-01 00:00:00
abstract::A possible role of the plasminogen/plasmin or fibrinolytic system in several biological processes has been implied from correlations between fibrinolytic activity and (patho)physiological phenomena. However, such indirect evidence does not allow to definitively establish the biological relevance of this system. Two re...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章,评审
doi:
更新日期:1995-07-01 00:00:00
abstract::Various tests were evaluated for their capacity to differentiate between platelet suspensions with different degrees of cell damage. Those suspensions were prepared by simultaneous isolation of platelets from the same platelet-rich plasma (PRP) using the following procedures: 1. centrifugation at 4 degrees C with EDTA...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:1978-02-28 00:00:00
abstract::The clinical severity in some patients with haemophilia A appears to be unrelated to the levels of factor (F)VIII activity (FVIII:C), but mechanisms are poorly understood. We have investigated a patient with a FVIII gene mutation at Arg1781 to His (R1781H) presenting with a mild phenotype despite FVIII:C of 0.9 IU/dl....
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:10.1160/TH12-10-0762
更新日期:2013-06-01 00:00:00
abstract::An assay of human antiplasmins has been developed utilizing radial diffusion of plasma from wells cut in plasmin-enriched, fibrinogen-agarose plates. After diffusion the fibrinogen is clotted. Zones of fibrin protected from background fibrinolysis develop as the result of plasma antiplasmin activity. A pooled plasma s...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:1978-04-30 00:00:00
abstract::Venous thromboembolism (VTE) is a multifactorial disease. Major provoking factors (e. g. surgery, cancer, major trauma, and immobilisation) are identified in 50-60 % of patients, while the remaining cases are classified as unprovoked. However, minor predisposing conditions may be detectable in these patients, possibly...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章,评审
doi:10.1160/TH14-06-0563
更新日期:2015-06-01 00:00:00
abstract::Haemophilia A and B are X-linked disorders which are due to a reduced activity of coagulation factor VIII or IX, respectively. Female carriers have a wide range of plasma concentration of factor VIII or factor IX, and may in rare cases have an affected phenotype. In order to investigate if this variation is related to...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:2000-03-01 00:00:00
abstract::The evidence is reviewed and a model presented for two distinct receptors being involved in platelet activation induced by alpha-thrombin: a high affinity thrombin receptor constituting approximately 50 copies of a supercomplexed form of GPIb coupled to phospholipase A2 and a moderate affinity receptor constituting ap...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章,评审
doi:
更新日期:1997-07-01 00:00:00
abstract::We aimed to determine the association between autoantibodies against apolipoprotein A-1 (anti-apoA-1 IgG) and prevalent cardiovascular (CV) disease (CVD) as well as markers of CV risk in the general population. Cross-sectional data were obtained from 6649 subjects (age 52.6 ± 10.7 years, 47.4 % male) of the population...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:10.1160/TH16-03-0248
更新日期:2016-09-27 00:00:00
abstract::Factor Xa (fXa)-inhibitors are as effective and safer than vitamin-K-antagonists (VKA) in the treatment of venous thromboembolism (VTE). We previously classified the severity of clinical presentation and course of all major bleeding events from the EINSTEIN, AMPLIFY and HOKUSAI-VTE trials separately. The current aim w...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:10.1160/TH16-12-0946
更新日期:2017-10-01 00:00:00
abstract::Vasopressin infusions in normal volunteers that produce concentrations in plasma comparable to those seen during stress, cause an increase in plasma factor VIII and shortening of the euglobulin clot lysis time (ECLT). We have investigated the relationship between endogenous vasopressin (aVP) release and haemostatic fu...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:1986-02-28 00:00:00
abstract::Diabetic subjects have been shown to have altered fibrin network structures. One possible cause may be fibrinogen glycation resulting in altered structure/function properties. We investigated the effect of glucose control on fibrinogen glycation and fibrin network structure in type 2 diabetes. Blood samples were taken...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:2006-11-01 00:00:00
abstract::Helicobacter pylori (H. pylori) infection is associated with peptic ulcer disease and gastric cancer. The eradication of H. pylori is of special interest in patients with congenital bleeding disorders, for whom treatment of gastrointestinal hemorrhage with factor concentrates is costly. The prevalence of H. pylori var...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:2003-04-01 00:00:00
abstract::Tissue factor (TF) plays a pivotal role in thrombus formation and atherogenesis in acute coronary syndrome. Tissue factor pathway inhibitor (TFPI) is a specific physiological inhibitor of TF/FVIIa complex that regulates TF-induced coagulation. Adiponectin (Adp) is an adipocyte-specific adipocytokine with anti-atheroge...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:2008-08-01 00:00:00
abstract::Fibrinogen degradation products were investigated for leukocyte chemotactic activity and for enhancement of vascular permeability. Both activities increased progressively with plasmin digestion of fibrinogen. Active fragments were partially purified from 24 hr-plasmin digests. Molecular weights of the permeability inc...
journal_title:Thrombosis and haemostasis
pub_type: 杂志文章
doi:
更新日期:1981-02-23 00:00:00