Репозиторий Университета

© 2019, The Author(s). Objectives: This study was aimed to assess hemostatic disturbances in female patients with established rheumatoid arthritis (RA) in relation to menopausal status and disease activity. Method: Ninety women were included in the study, 42 patients and 48 age-matched healthy controls. There were no differences between the investigated groups regarding the presence of traditional cardiovascular risk factors. Two global hemostatic assays were employed, namely endogenous thrombin potential (ETP) and overall hemostasis potential (OHP). The parameters of the ETP assay (ETP, C-max, t-lag, t-max) and OHP assay (overall coagulation potential (OCP) and overall fibrinolytic potential (OFP)) were assessed. Moreover, the parameters of the fibrin clot (lag time, Max Abs, and slope) were measured by clot turbidity and scanning electron microscopy (SEM). Both patients and controls were divided into four subgroups according to menopause status. Results: The premenopausal controls differed significantly from all other subgroups in terms of diminished levels of ETP (p = 0.02), C-max (p = 0.01), OCP (p = 0.02), OHP (p = 0.001), and Max Abs (p = 0.008), while OFP (p = 0.0001) was increased. This tendency was not seen in the premenopausal RA patients compared with the postmenopausal RA patients. SEM images showed denser clots composed of thinner fibers in samples from RA patients. The disease activity measured by DAS28 correlated with OCP and OHP (r = 0.54; p = 0.001 and r = 0.44; p = 0.003, respectively) indicating persistent hypercoagulable condition in the whole group of RA patients. Conclusions: Our results point towards coagulation activation in premenopausal women with established RA. The patients were well characterized, which enabled assessment in a real-life setting.Key Points• Extensive assessment points towards persistent coagulation activation in premenopausal women with established rheumatoid arthritis.• Impaired thrombin generation and fibrin formation are associated with menopause in healthy women, while rheumatoid arthritis closes the gap within patients regarding menopause.• Fibrin morphology is unfavorably altered and fibrinolysis is decreased in patients with established rheumatoid arthritis.• Increased activity of thrombin activatable fibrinolysis inhibitor (TAFI) may contribute to impaired fibrinolysis in patients with rheumatoid arthritis.

© Russian Association of Endocrinologists, 2018. BACKGROUND. Intensive glycaemic control in patients with type 1 diabetes may lead to hypoglycaemia and thus increase the risk of cardiovascular and cerebrovascular events. Platelet activation and/or decreased activity of physiological anticoagulants during hypoglycaemia may play a role in the development of cardiovascular or cerebrovascular complications. AIMS. To investigate induced platelet activity, the activity of physiological anticoagulants, and the von Wil-lebrand factor in patients with type 1 diabetes with the hyperinsulinaemic-hypoglycaemic clamp. MATERIALS AND METHODS. We examined 11 patients with type 1 diabetes without macro- and micro-vascular complications (6 males, 5 females, mean age 23.7 ± 5.6 years, A1C 9.7 ± 2.3%). Induced platelet aggregation, physiological anticoagulants (Protein S, Protein C, AT III) and the von Willebrand factor were studied at hyperglycaemic, euglycaemic, and hypoglycaemic stages during use of a hyperinsulinaemic (1 mU/kg/min) hypoglycaemic clamp. RESULTS. Platelet aggregation to all agonists increased significantly during the hypoglycaemic stage, compared with the euglycaemic or hyperglycaemic stages. There was no difference in platelet aggregation between the euglycaemic and hyperglycaemic stages. Platelet aggregation to all agonists increased during the hypoglycaemic stage compared with the hyperglycaemic period: thrombin-23.9%, ADP-30.6%, arachidonic acid-30.9%, collagen-69.4% and ristocetin-70.8%. During hypoglycaemia aggregation to ADP, arachidonic acid and collagen remained within normal limits (upper quartile); aggregation to thrombin was significantly above normal limits and aggregation to ristocetin remained significantly below lower limits. Protein S activity was significantly increased during hypoglycaemia compared with euglycaemia (p = 0.046) and hyperglycaemia (p = 0.046). Antithrombin-III activity decreased significantly at the euglycaemic and hypoglycaemic stages, compared with the hyperglycaemic period, but still remained significantly elevated above the upper threshold. Protein C and vWf activity did not change significantly. CONCLUSIONS. In patients with type 1 diabetes platelet aggregation and protein S activity increases significantly at the hypoglycaemic stage of the hyperinsulinaemic-hypoglycaemic clamp. Platelet activation is directly caused by hypoglycaemia and not by decreasing glucose levels. Increased protein S activity is a compensatory response to platelet activation.

© 2018, Dynasty Publishing House. The assessment of thrombosis and bleeding risks is one of the most important tasks of laboratory diagnostics of disorders in the hemostasis system. For this purpose the highly specialized tests are not always appropriate, because these assays are focused on specific markers or pathologies of individual links: the level of coagulation factors, the level of D-dimers, ADP- and serotonininduced platelet activation, effects of acetyl salicylic acid on aggregation. Nowadays, integral assays are the most promising approach, simulating hemostatic process in vivo - thromboelastography, thrombodynamics, thrombin generation. These tests are designed to specify the risk of thrombosis or bleeding with co-origin, as well as screening and monitoring of drug therapy. One of the approaches in the development of integral assays are flow systems where plasma or whole blood flow is formed over the hemostatic activator, and the growth of the thrombus is recorded on the video. There are commercially available samples of such devices, and some experience of its application in clinic. However, there are no uniform standards and clinical guidelines. This review describes examples of flow chambers exploitation for diagnosis, existing problems of its usage and the opportunities that it can provide to the clinicians.