Thrombosis research
-
Thrombosis research · Jan 2006
ReviewAdvances in the pathogenesis, diagnosis and treatment of thrombotic thrombocytopenic purpura and hemolytic uremic syndrome.
The thrombotic microangiopathies are microvascular occlusive disorders characterized by hemolytic anemia caused by fragmentation of erythrocytes and thrombocytopenia due to increased platelet aggregation and thrombus formation, eventually leading to disturbed microcirculation with reduced organ perfusion. Depending on whether brain or renal lesions prevail, two different entities have been described: thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS). ⋯ Recent studies have contributed greatly to our current understanding of the molecular mechanisms leading to TTP and HUS. In this review, we briefly focus on the most important advances in the pathophysiology, diagnosis and treatment of these two thrombotic microangiopathies.
-
Thrombosis research · Jan 2006
Fibrinogen Guarenas, an abnormal fibrinogen with an Aalpha-chain truncation due to a nonsense mutation at Aalpha 467 Glu (GAA)-->stop (TAA).
Fibrinogen Guarenas is a dysfibrinogenemia with a nonsense mutation at G4731T that causes an Aalpha-chain truncation at Ser 466. This abnormal fibrinogen is associated with a bleeding diathesis, severe in the proposita and mild in one brother, even though the fibrinogen levels in plasma are normal. All other family members are asymptomatic. ⋯ When Guarenas clots were perfused with fibrinolytic enzymes, clot degradation was retarded. Clot structure studied by confocal 3D microscopy showed that the fibrin network was dense, made up of thin and highly branched fibers, which accounted for the decreased flow rates by buffer permeation and increased rigidity of the fibrin clots, measured using a torsion pendulum. It seems that the increased clot rigidity, decreased porosity, hypofibrinolysis and t-PA induced fibrinolysis, by itself are not necessarily associated with thrombotic disorders in dysfibrinogenemia.
-
Aspirin overprescription is of some concern, especially in still-healthy individuals, and estimates of the magnitude of this problem are lacking. We evaluated the inappropriateness of aspirin prescription by primary care physicians in primary cardiovascular prevention. ⋯ A non-negligible proportion-up to 18%-of subjects in primary prevention is currently more likely to derive harm than benefit from inappropriate aspirin use. A wider use of Cardiovascular Risk Charts should guide primary care physicians in prescribing aspirin for primary prevention.
-
Thrombosis research · Jan 2006
Comparative StudyGene--nutrition interactions in coronary artery disease: correlation between the MTHFR C677T polymorphism and folate and homocysteine status in a Korean population.
Elevated plasma total homocysteine is a major risk for coronary artery disease (CAD). Methyltetrahydrofolate reductase (MTHFR) is a main regulatory enzyme in homocysteine metabolism; a common C677T mutation in the MTHFR gene results in decreased enzyme activity, and contributes to increased homocysteine levels and decreased folate levels. We investigated the frequency of MTHFR C677T alleles in a Korean population, determined the genotype-specific threshold levels of folate or vitamin B12, and investigated the relationship between the TT genotype and the risk of CAD. ⋯ We were able to define a gene-nutrient interaction that shows a higher risk for CAD based on specific threshold folate levels required by different MTHFR C677T genotypes in a Korean population.
-
Thrombosis research · Jan 2006
Normal values for thrombelastography (ROTEM) and selected coagulation parameters in porcine blood.
The pig is a suitable animal model for researching blood coagulation and fibrinolysis. The present study therefore aimed to investigate in porcine blood the applicability of commercially available tests of coagulation and thrombelastography (ROTEM) and above all to determine normal values for coagulation parameters (e.g. prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin-antithrombin complexes (TAT), fibrinogen, antithrombin III (AT III), D-dimers, protein C). ⋯ Normal values and reference intervals for porcine blood are given. As compared to the human reference intervals for the coagulation parameters investigated, porcine blood was found to be hypercoagulable.