Immunological and hemostasiological aspects of pathogenesis of obliterating atherosclerosis of arteries of the lower extremities

Objectives to study the changes in the immunological status and hemostatic system in patients with obliterating atherosclerosis of the lower limb arteries with the damage to the femoral-popliteal-tibial segment. Material and methods. A comprehensive study of the cytokine status and hemostatic system in patients with obliterating atherosclerosis of lower limb arteries with lesions of the femoral-popliteal tibia segment was carried out. Results. The progressive course of obliterating atherosclerosis is often associated with an increased content of cytokines (IL-1, IL-6, IL-8, TNF), as well as with the phenomena of hypercoagulation (increased platelet aggregation activity, shortened APTT, CT, TT, increased fibrinogen content), SFMCs, D-dimer). Conclusion. The study of the immunological status and hemostatic system should be performed in all patients with obliterating atherosclerosis of the lower limb arteries in order to adequately medically correct and prevent postoperative complications.

Influence of Rhesorbilact on rheological properties of blood in patients with acute peritonitis

Objective. Study of the effect of Rheosorbilact on the rheological properties of blood in patients with acute peritonitis. Materials and methods. 62 patients with acute peritonitis at the age from 20 to 87 years were examined. The patients were divided into two groups depending on the inclusion of Rheosorbilact solution in the infusion therapy program. The first group (control) included 30 patients with the infusion therapy program consisted of conventional crystalloid and colloidal infusions. The second (main) group included 32 patients with the treatment of Rheosorbilact infusion therapy program at an average dose of 5.7-6.6 ml/kg (400 ml per day). The rheological properties of blood were studied by determining the relative blood viscosity with a VK-4 viscometer, hematocrit, fibrinogen and ESR according to generally accepted methods. Results. In patients with acute peritonitis, when Rheosorbilact (main group) is included in the infusion therapy program, there is a significant improvement in the rheological properties of blood compared with the results of the control group who received crystalloids and colloids. After treatment in patients of the control group, the indicators of the rheological properties of blood were characterized by a decrease in hematocrit – by 16.5 %, blood viscosity – by 11.6 %, fibrinogen content – by 15.2 %, ESR – by 18.2 % compared to the initial data. In patients of the main group who received Rheosorbilact in the infusion therapy program, the rheological properties of the blood significantly improved and amounted to 24.0 % in comparison with the initial data on hematocrit, 18.7 % in blood viscosity, 21.0 % in fibrinogen, and 23.4 % in ESR. Conclusions. In patients with acute peritonitis, a significant violation of the rheological properties of blood is observed. The inclusion of Rheosorbilact in the infusion therapy program contributes to the correction of impaired blood.

Peculiarities of plasma hemostasis in patients with Ph-negative myeloproliferative neoplasms

Введение: Тромбозы являются одним из основных осложнений Ph-негативных миелопролиферативных новообразований (МПН), таких как истинная полицитемия (ИП), эссенциальная тромбоцитемия (ЭТ) и первичный миелофиброз (ПМФ). Имеются многочисленные свидетельства активации тромбоцитов, лейкоцитов, эндотелия и коагуляции при МПН; однако результаты определения показателей гемостаза, применимых в клинической практике для выявления протромботических состояний при МПН, неоднозначны. Цель исследования: оценить состояние плазменного звена гемостаза у пациентов с Ph-негативными МПН и выявить показатели, отражающие протромботическую направленность изменений в системе гемостаза при данных патологиях. Материалы и методы: В исследование было включено 116 пациентов с МПН (43 с ИП, 35 с ЭТ, 38 с ПМФ). Пациенты находились на антиагрегантной, циторедуктивной и таргетной терапии ингибиторами янус-киназ. Контрольная группа состояла из 43 практически здоровых лиц. В плазме крови всех обследованных определяли индекс активированного парциального тромбопластинового времени (АПТВ) — отношение АПТВ исследуемого образца к АПТВ нормальной плазмы, протромбиновый тест по Квику (ПТ), содержание фибриногена, активности фактора VIII (FVIII) и естественных антикоагулянтов антитромбина (АТ) и протеина С (PC), уровень свободного протеина S (PS), а также показатели теста генерации тромбина (ТГТ), в том числе с добавлением тромбомодулина (ТМ). Результаты: У пациентов с МПН по сравнению с контрольной группой наблюдали сдвиг АПТВ и ПТ в сторону гипокоагуляции, было удлинено время инициации генерации тромбина, снижена скорость и количественные показатели ТГТ без добавления ТМ. При проведении ТГТ с добавлением ТМ у больных МПН выявлено снижение чувствительности к ТМ, которое коррелировало с падением активности PC и уровня свободного PS. Содержание фибриногена и активность FVIII у обследованных пациентов были повышены. Заключение: Для пациентов с МПН характерны разнонаправленные изменения показателей плазменного звена гемостаза. Важной детерминантой развития протромботических состояний при МПН выступает недостаточная эффективность естественных антикоагулянтов системы протеина С, приводящая к выраженному дисбалансу в системе гемостаза. Background: Thromboses are one of the main complications of Ph-negative myeloproliferative neoplasms (MPN), such as polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). There are abundant evidences of platelet, leukocyte, endothelial, and coagulation activation in MPN; however, studies of hemostatic parameters applicable in clinical practice for revealing of prothrombotic states in MPN are not identical. Objectives: to assess plasma hemostasis in patients with Ph-negative MPN and to identify parameters reflecting the prothrombotic tendency of hemostatic changes in these pathologies. Patients/Methods: The study included 116 patients with MPN (43 with PV, 35 with ET, 38 with PMF). Patients were treated with antiplatelet, cytoreductive and targeted therapy with Janus kinases inhibitors. The control group consisted of 43 healthy individuals. In blood plasma of all examined persons we determined the index of activated partial thromboplastin time (APTT) — the ratio of APTT of the test sample to APTT of normal plasma, Quick prothrombin test (PT), fi brinogen content, activities of factor VIII (FVIII) and natural anticoagulants — antithrombin (AT) and protein C (PC), free protein S (PS) level, as well as thrombin generation assay (TGA) parameters, including thrombomodulin (TM) addition. Results: As compared with control group, in patients with MPN a shift in APTT and PV to hypocoagulation was observed, the initiation time of thrombin generation was prolonged, the rate and quantitative parameters of TGA without TM addition were decreased. In patients with MPN TGA with TM addition showed reduced sensitivity to TM that correlated with decreased PC activity and reduction of free PS level. Fibrinogen content and FVIII activity in the examined patients were increased. Conclusions: Patients with MPN are characterized by multidirectional changes of plasma hemostasis parameters. The important determinant of prothrombotic states development in MPN is insufficient effectiveness of the natural anticoagulants of protein C system that leads to expressed hemostasis imbalance.

Cryoprecipitate transfusion in bleeding patients

ABSTRACTObjectivesThe management of acquired coagulopathy in multiple clinical settings frequently involves fibrinogen supplementation. Cryoprecipitate, a multidonor product, is widely used for the treatment of acquired hypofibrinogenemia following massive bleeding, but it has been associated with adverse events. We aimed to review the latest evidence on cryoprecipitate for treatment of bleeding.MethodsWe conducted a narrative review of current literature on cryoprecipitate therapy, describing its history, formulations and preparation, and recommended dosing. We also reviewed guideline recommendations on the use of cryoprecipitate in bleeding situations and recent studies on its efficacy and safety.ResultsCryoprecipitate has a relatively high fibrinogen content; however, as it is produced by pooling fresh frozen donor plasma, the fibrinogen content per unit can vary considerably. Current guidelines suggest that cryoprecipitate use should be limited to treating hypofibrinogenemia in patients with clinical bleeding. Until recently, cryoprecipitate was deemed unsuitable for pathogen reduction, and potential safety concerns and lack of standardized fibrinogen content have led to some professional bodies recommending that cryoprecipitate is only indicated for the treatment of bleeding and hypofibrinogenemia in perioperative settings where fibrinogen concentrate is not available. While cryoprecipitate is effective in increasing plasma fibrinogen levels, data on its clinical efficacy are limited.ConclusionsThere is a lack of robust evidence to support the use of cryoprecipitate in bleeding patients, with few prospective, randomized clinical trials performed to date. Clinical trials in bleeding settings are needed to investigate the safety and efficacy of cryoprecipitate and to determine its optimal use and administration.

Coronavirus disease (COVID-19) and disseminated intravascular coagulation syndrome

COVID-19 is an infectious disease caused by the beta-coronavirus SARS-CoV-2 that in 2020 has spread worldwide. In most severe patients, the clinical picture begins with respiratory failure further deteriorating up to multiple organ failure. Development of coagulopathy is the most adverse prognostic. Analyzing currently available clinical data revealed that 71.4 % and 0.6 % of survivors and fatal cases, respectively, demonstrated signs of overt disseminated intravascular coagulation (DIC). Monitoring D-dimer level, prothrombin time, platelet count and fibrinogen content is important for determining indications for treatment and hospitalization in COVID-19 patients. In case such parameters deteriorate, a more pro-active “aggressive” intensive care should be applied. Low molecular weight heparin (LMWH) should be administered to all patients with diagnosed COVID-19 infection (including non-critical patients) requiring hospitalization, but having no contraindications to LMWH.

Tunable Fibrin-Alginate Interpenetrating Network Hydrogels to Guide Cell Behavior

ABSTRACTHydrogels are effective platforms for use as artificial extracellular matrices, cell carriers, and to present bioactive cues. Two common natural polymers, fibrin and alginate, are broadly used to form hydrogels and have numerous advantages over synthetic materials. Fibrin is a provisional matrix containing native adhesion motifs for cell engagement, yet the interplay between mechanical properties, degradation, and gelation rate is difficult to decouple. Conversely, alginate is highly tunable yet bioinert and requires modification to present necessary adhesion ligands. To address these challenges, we developed a fibrin-alginate interpenetrating network (IPN) hydrogel to combine the desirable adhesion and stimulatory characteristics of fibrin with the tunable mechanical properties of alginate. We tested its efficacy by examining capillary network formation with entrapped co-cultures of mesenchymal stromal cells (MSCs) and endothelial cells (ECs). We manipulated thrombin concentration and alginate crosslinking density independently to modulate the fibrin structure, mesh size, degradation, and biomechanical properties of these constructs. In IPNs of lower stiffness, we observed a significant increase in total cell area (1.72×105 ± 7.9×104 μm2) and circularity (0.56 ± 0.03) compared to cells encapsulated in stiffer IPNs (3.98×104 ± 1.49×104 μm2 and 0.77 ± 0.09, respectively). Fibrinogen content did not influence capillary network formation. However, higher fibrinogen content led to greater retention of these networks confirmed via increased spreading and presence of F-actin at 7 days. This is an elegant platform to decouple cell adhesion and hydrogel bulk stiffness that will be broadly useful for cell instruction and delivery.

L-NAME-induced Preeclampsia: correction of functional disorders of the hemostasis system with Resveratrol and Nicorandil

Introduction. Preeclampsia is a formidable disease of the second half of pregnancy, leading to severe complications, including disability and even death. Many authors have recognized the correlation between the severity of preeclampsia and the degree of disturbances in the hemostasis system. In this regard, the objective of this study was to assess inhibition of platelet aggregation and the possibility of its correction with resverаtrol and nicorandil. Materials and methods. The study was performed on 250 mature white Wistar female rats weighing 250–300 g. The platelet aggregation induced by ADP, collagen, ristomycin, adrenaline was determined, as well as PTT, TT, aPTT, fibrinogen, and the clotting time. Results and discussion. Introduction of resverаtrol and nicorandil resulted in a decrease in thrombocyte aggregation capacity from 53.8 ± 2.60% to 22.1 ± 1.25% and 37.1 ± 1.79%, respectively, when using ADP as an inducer. The clotting time was from 841 ± 42 s up to 1135 ± 33 s and 1034 ± 26 s, respectively. In addition, there was an increase in temporal parameters of plasma-coagulation hemostasis and a decrease in plasma fibrinogen content. The use of glibenclamide resulted in partial cancellation of the positive effects of resverаtrol and nicorandil, with an increase in platelet aggregation to 28.9 ± 1.8% and 43.9 ± 1.2% when using ADP as an inducer and a decrease in the thrombosis time to 988 ± 26 s and 950 ± 22 s, respectively. Conclusion. In animals with experimental preeclampsia, there were disturbances in the hemostasis system, comparable to those in the clinical situation. The use of resverаtrol and nicorandil leads to a pronounced correction of hemostasis parameters. The positive effects of the studied pharmacological agents are mediated by several mechanisms, including K+ATP channels.

THE DIFFERENCE OF TENSILE STRENGTH AND YIELD FIBRINOGEN ON FIBRIN GLUE PREPARATIVE BY CRYOPRESIPITATE WITH AND WITHOUT FREEZE DRYING METHODS

Fibrin glue is a useful biological product to stop bleeding, adhesive tissue and accelerate wound healing. Preparation of Fibrin Glue requires fibrinogen and thrombin components. The routine cryoprecipitation method performed at the Blood Bank can be used to improve the quality of the fibrinogen component. The Freeze Drying process can increase the retention time of plasma products at room temperature. Yield Fibrinogen and Tensile Strength is a quantitative and qualitative parameter of preparation quality of fibrin glue. This study focused on finding differences between Tensile Strength and Yield Fibrinogen on fibrin glue preparative by cryoprecipitate with and without freeze drying methods.This study is in vitro laboratory experiments design by comparing the Yield Fibrinogen and Tensile Strength of fibrin glue preparation from cryoprecipitic plasma with and without freeze dried process. The results were analyzed comparatively using paired T test.The plasma fibrinogen content of the sample was 237.66 ± 67.10 mg / dL. The fibrinogen content of the cryoprecipitate component without freeze drying process was 327.74 ± 103.42 mg / dL with a yield fibrinogen of 1.38 ± 0.25. The fibrinogen content of the cryoprecipitate component with freeze drying process was 251.20 ± 103.91 mg / dL with yield fibrinogen 1.04 ± 0.25. Tensile strength of fibrin glue from cryoprecipitate without freeze drying process was found to average 0.52 ± 0.18. Tensile strength of fibrin glue from cryoprecipitate with freeze drying process was found to average 0.33 ± 0.12. There was a significant difference between yield fibrinogen and tensile strength of fibrin glue preparation of cryoprecipitation method with and without freeze dried process.There is a significant difference on yields fibrinogen and tensile strength in the preparation of fibrin glue by the freeze drying process which is probably due to changes in the structure and function of fibrinogen proteins.

Personalized approach to procurement of hemocomponents taking into account hemostasis characteristics of donors

Цель исследования: изучение параметров гемостаза у доноров для оптимизации использования компонентов крови у пациентов с нарушениями свертывания крови. Материалы и методы. Проанализированы результаты коагулологического исследования крови у 200 доноров. Контрольную группу составили 50 человек — здоровые люди (добровольцы), не доноры в возрасте от 20 до 60 лет. Измеряли: время свертывание крови по Ли-Уайту, активированное частичное тромбопластиновое время, международное нормализованное отношение, агрегацию тромбоцитов, антитромбин III (АТ-III), содержание фибриногена по Клаусу, фактор фон Виллебранда (ФВ), активность фактора VIII. Рассчитывали среднюю арифметическую и среднюю ошибку средней арифметической (М ± m), для оценки значимости различий средних величин использовали t-критерий Стьюдента, различия считали статистически значимыми при р < 0,05. Результаты. Оценка показателей гемостаза показала как развитие у доноров склонности к гиперкоагуляции, так и компенсаторную активацию антикоагулянтной системы. В зависимости от возраста и количества кровосдач агрегация тромбоцитов, АТ-III, содержание фибриногена, активность ФВ и фактора VIII в заготовленных компонентах крови получаются различными. Заключение. Трансфузионная терапия коагулопатий может быть оптимизирована за счет применения компонентов крови, целенаправленно заготовленных с учетом характера нарушений свертывания крови у реципиента. Aim: to optimize the usage of blood components in patients with coagulopathy we analyze some hemostasis parameters in donors. Materials and methods. In 200 donors and 50 healthy volunteers (aged from 20 to 60 years old) we analyzed hemostatic parameters: whole blood clotting time, activated partial thromboplastin time, international normalized ratio, platelet aggregation, antithrombin III (AT-III), Claus fibrinogen content, activity of von Willebrand factor (VWF) and factor VIII. The results obtained presented as M ± m. Statistical diff erences by Student test were considered as signifi cant for p < 0,05. Results. All donors had the tendency to hypercoagulation with compensatory activation of anticoagulant system. Depending on the age and number of blood donations, obtained blood components were diff erent in platelet aggregation, AT-III level, fibrinogen content, activity of VWF and factor VIII. Conclusion. Transfusion therapy of coagulopathies can be optimized through the use of blood components purposefully prepared taking into account the nature of blood clotting disorders in the recipient.