Activation Of Hemostasis Research Articles

A contemporary view of the problem of destructive pneumonia in children

The problem of community-acquired pneumonia in children remains relevant at the present time. Complicated forms, which include pleural empyema, abscess, necrotizing pneumonia, bronchopleural fistulas and acute respiratory distress syndrome do not decrease, despite modern antibacterial therapy and the availability of vaccination against pneumococcus. The main pathogens associated with lung destruction in children are S. pneumoniae and S. aureus, often MRSA. The role of other pathogens in necrotizing pneumonia is much less frequently reported: Streptococcus pyogenes, Haemophilus influenzae, Pseudomonas aeruginosa, Fusobacterium nucleatum, Legionella pneumophila, Klebsiella pneumoniae, anaerobes. However not only pathogenic factors of the pathogen are important for necrotizing pneumonia development. Often, a viral prodrome, often associated with the influenza A (H1N1) virus, precedes complicated pneumonia. During the epidemic of COVID-19, endothelial damage with a high degree of probability was a predisposing factor for the development of a secondary bacterial infection with lung tissue necrosis. Significant destruction and liquefaction of the lung tissue may develop despite adequate antibiotic therapy. Great importance in the development of necrosis is attached to the activation of hemostasis and thrombus formation in the vessels of the lungs. Timely diagnosis often is difficult due to the predominance of general symptoms over local ones, especially in young children. Chest x-ray is the standard for diagnosing. However, the diagnostic capabilities of this method in necrotizing pneumonia are limited. To assess a number of parameters of the state of the pleural cavity and lung tissue, ultrasound is preferred. It is necessary to analyze the current features of the course of necrotizing pneumonia in children and develop clinical guidelines for the management of patients in the acute period and rehabilitation.

An impact of neutrophil extracellular traps to the prothrombotic state and tumor progression in gynecological cancer patients

Introduction. One of the leading causes in the mortality pattern of cancer patients is accounted for by thrombotic complications. Recent studies have shown that neutrophil extracellular traps (NETs) are involved in the activation of coagulation, contribute to the initiation and progression of thrombosis. In addition, NET-related effect on tumor progression and metastasis has been actively studied.Aim: to evaluate NET-related procoagulant activity in gynecological cancer patients.Materials and Methods. From April 2020 to October 2022, a prospective controlled interventional non-randomized study was conducted with 120 women. The main group included 87 patients aged 32 to 72 years with malignant neoplasms of the female genital organs and mammary glands who were hospitalized for elective surgical treatment or chemotherapy: uterine body cancer (subgroup 1; n = 18), ovarian cancer (subgroup 2; n = 26), cervical cancer – adenocarcinoma of the cervical canal (subgroup 3; n = 13), breast cancer (subgroup 4; n = 30). The control group consisted of 33 healthy women aged 32 to 68 years. In all women, plasma concentrations of citrullinated histone H3 (citH3), myeloperoxidase antigen (MPO:Ag), D-dimer, and thrombin–antithrombin (TAT) complexes were evaluated.Results. The magnitude of NETosis in cancer patients, assessed by level of citH3 (2.5 ± 0.7; 1.9 ± 0.8; 2.5 ± 0.7; 0.7 ± 0.5 ng/ml in four subgroups, respectively) and MPO:Ag (29.5 ± 13.1; 12.8 ± 3.7; 22.8 ± 8.7; 6.6 ± 2.5 ng/ml in four subgroups, respectively) was significantly higher compared to women in the control group (0.3 ± 0.1 ng/ml; p = 0.0001 and 2.5 ± 0.2 ng/ml; p = 0.0001). In parallel with increased NETosis markers in accordance with the disease stage, there was an increase in the concentration of hemostasis activation markers – D-dimer (1.7 ± 0.6; 2.0 ± 0.7; 1.4 ± 0.5; 1.5 ± 0.7 µg/ml in four subgroups, respectively) and TAT complexes (729.8 ± 43.9; 794.1 ± 164.8; 636.2 ± 149.5; 699.6 ± 165.7 pg/ml in four subgroups, respectively) exceeding their level in the control group (respectively, 0.4 ± 0.1 μg/ml; p = 0.0001 and 362.3 ± 0.1 pg/ml; p = 0.0001). The maximum values of parameters occurred at later stages according to the Classification of Malignant Tumours (tumor, nodus, metastasis, TNM). A significant correlation between TAT level and the concentrations of citH3 (r = 0.586; р = 0.04) and MPO:Ag was revealed (r = 0.631; р = 0.04).Conclusion. Tumor tissue creates milieu that stimulates NETs release, which, in turn, not only contribute to the creating a procoagulant state, but also might act as one of the factors that ensure tumor progression and metastasis. The development of targeted therapies acting on NETs has a potential to affect hemostasis in cancer patients and reduce rate of tumor growth and metastasis.

Clinical significance of assessing ADAMTS-13 and von Willebrand factor level in COVID-19 convalescent pregnant women

Introduction. Coronavirus infection is associated with severe endotheliopathy, thromboinflammation and immunothrombosis leading to excessive release of von Willebrand factor (vWF) multimers from Weibel–Palade bodies, which can affect activity of ADAMTS-13 metalloproteinase (a disintegrin and metalloproteinase with thrombospondin type 1 motif, member 13) and the ADAMTS-13/vWF axis previously shown by us to be altered in non-pregnant women with severe COVID-19. Aim: to study a clinical role of hemostasis activation particularly ADAMTS-13/vWF axis in pregnant women after COVID-19. Materials and Methods. A prospective case–control study was conducted with pregnant women (n = 135) divided into 3 groups: group 1 included 45 women with prior COVID-19 during pregnancy, group 2 – 45 women in the acute phase of the infection during pregnancy, group 3 – 45 healthy pregnant women. The level of vWF and ADAMTS-13 was assessed in all patients. Results. The concentration of vWF antigen (vWF:Ag) in the acute period of the disease in pregnant women with COVID-19 was significantly higher compared to the control group (p < 0.001). ADAMTS-13 level in pregnant women after COVID-19 did not differ from that of in control group, while vWF level was significantly higher in 66.7 % (30/45). The ADAMTS-13/vWF ratio was increased and significantly differed both in pregnant patients during the acute period of the disease (p < 0.001) and pregnant women after infection (p = 0.0002) compared with the control group. Conclusion. Our results show that endotheliopathy was prominently manifested in pregnant women with COVID-19 and persisted for several months after disease. The ADAMTS-13/vWF ratio determines the pathway functioning, the risk of microcirculation disorders and clinical complications.

An anticoagulant/procoagulant self-converting and bleeding site–targeting systemic nanotherapy for rapidly controlling noncompressible bleeding without risk of thrombosis

BackgroundHemorrhage, in particular noncompressible hemorrhage, is the leading cause of casualties in combat trauma and civilian trauma. Although systemic agents can stop bleeding at both inaccessible and accessible injury sites, the application of systemic hemostats in clinics is strictly limited by the nontargeting ability of hemostats and their subsequent potential for thromboembolic complications. ObjectivesTo engineer an anticoagulant/procoagulant self-converting and bleeding site–targeting systemic nanohemostat to rapidly control noncompressible bleeding without thrombosis risk. MethodsA multiscale computer simulation was taken to guide the self-assembly of sulindac (SUL, a prodrug of the antiplatelets agent) and poly-L-lysine (a cation polymer with platelets activation ability) for forming poly-L-lysine/SUL nanoparticles (PSNs). In vitro platelet-adhering ability, platelet activation effect, and hemostasis activity of PSNs were evaluated. Then, the biosafety, level of thrombosis, targeting ability, and hemostasis effect of systemic applied PSNs were carefully evaluated in various hemorrhage models. ResultsPSNs were successfully prepared and showed good platelet adhesion and activation in vitro. The bleeding site–targeting ability and hemostatic efficiency in different bleeding models were leveled up by PSNs markedly compared with vitamin K and etamsylate in vivo. SUL in PSNs could be metabolized into sulindac sulfide at clot sites in 4 hours for antiplatelet aggregation, thus reducing thrombotic risk compared with other hemostatic agents, via the ingenious utilization of prodrug metabolism in terms of time intervals and the adhesion on platelets. ConclusionPSNs are expected to be a low-cost, safe, efficient, clinically translatable first-aid hemostat for first-aid scenarios.

Role of pyroptosis in hemostasis activation in sepsis.

Sepsis is frequently associated with hemostasis activation and thrombus formation, and systematic hemostatic changes are associated with a higher risk of mortality. The key events underlying hemostasis activation during sepsis are the strong activation of innate immune pathways and the excessive inflammatory response triggered by invading pathogens. Pyroptosis is a proinflammatory form of programmed cell death, that defends against pathogens during sepsis. However, excessive pyroptosis can lead to a dysregulation of host immune responses and organ dysfunction. Recently, pyroptosis has been demonstrated to play a prominent role in hemostasis activation in sepsis. Several studies have demonstrated that pyroptosis participates in the release and coagulation activity of tissue factors. In addition, pyroptosis activates leukocytes, endothelial cells, platelets, which cooperate with the coagulation cascade, leading to hemostasis activation in sepsis. This review article attempts to interpret the molecular and cellular mechanisms of the hemostatic imbalance induced by pyroptosis during sepsis and discusses potential therapeutic strategies.

Агрегация тромбоцитов у женщин с нефролитиазом при назначении неселективных НПВП

Aim: to evaluate the effect of adrenergic and purinergic signaling in platelets (PLT) during COX inhibition on the severity of hematuria in women with nephrolithiasis (NLT). Material and Methods. The study was prospective and included 60 patients with imaging evidence of urinary tract stones, who were treated with high doses of non-selective non-steroidal anti-inflammatory drugs (NSAIDs) as part of lithokinetic therapy (LKT) for analgesia. The study included 30 women who had reproducible TP-receptor hyporeactivity (<45%) after 72h of LKT with non-selective NSAIDs. The severity of hematuria was assessed at the time of hospitalization and for 7 days of LCT. The activity of the TP receptor, α2-adrenergic receptor, purine P2X1- and P2Y-receptors (P2Y1, P2Y12) was studied by turbidimetric method on a ChronoLog analyzer (USA). Agonists (arachidonic acid, epinephrine, ATP and ADP) were used at EC50 and EC10 concentrations. Statistical analysis was performed using the MedCalc package. Results. After 72 hours of LCT, the activity of the TP receptor, α2-adrenergic receptor and purine P2-receptors of PLT decreased and reached the level of hyporeactivity. Recovery of the activity of P2X1- and P2Y-receptors to the level of normoreactivity was registered after 5 days, while the activity of the α2-adrenergic receptor remained in the range of hyporeactivity. On day 7, α2-adrenergic receptor and P2X1-receptor hyperreactivity developed and P2Yreceptor normoreactivity remained. The effectiveness of compensatory reactions of PLT aimed at limiting hematuria depended on the synergism of functionally active receptors. Conclusion. In women with nephrolithiasis during the administration of non-selective NSAIDs, the spontaneous increase in α2- adrenoreceptor activity is indicative of the lability of the sympathoadrenal system caused by the trafficking of stones in the urinary tract. The limitation of hematuria observed in this case is associated with increased proaggregation activity of platelet hemostasis due to synergism of α2-adrenoreceptor and P2-receptors.

Fluctuations in Thyroid Hormone Levels During Initial Treatment for Differentiated Thyroid Carcinoma are Associated with Changes in Hemostasis: A Prospective Cohort Study.

Background: During treatment for differentiated thyroid carcinoma (DTC), patients go from euthyroidism to severe hypothyroidism to subclinical hyperthyroidism induced by thyroid hormone suppression therapy (THST). Severe hypothyroidism may induce a tendency toward bleeding, whereas hyperthyroidism is thrombogenic. Therefore, treatment for DTC may increase the risk of bleeding during thyroid hormone withdrawal, and thrombosis during THST. This study aims to provide prospective analysis of changes in the hemostatic system from euthyroidism to hypothyroidism, and during THST, in patients treated for DTC. Methods: This is a secondary study in a larger Dutch prospective cohort. Consecutive samples were obtained from 20 patients (18 female [90%]; median age 48 [interquartile range 35.8-56.5] years) throughout their treatment for DTC during euthyroidism (n = 5), severe hypothyroidism (n = 20), and THST (n = 20). We measured selected hemostatic proteins and C-reactive protein (CRP), performed functional tests of hemostasis (a thrombin generation test and a plasma-based clot lysis test), and assessed markers of in vivo activation of hemostasis (thrombin-antithrombin complexes, plasmin-antiplasmin [PAP] complexes, and D-dimer levels). Results: During hypothyroidism, the majority of measured parameters did not change. During THST, plasma levels of nearly all measured hemostatic proteins were higher than during hypothyroidism. Additionally, CRP significantly increased from 1.3 (0.5-3.3) to 3.2 (1.3-5.1) mg/L during THST (p < 0.01). Ex vivo thrombin generation increased from 626.0 (477.0-836.3) to 876.0 (699.0-1052.0) nM × min (p = 0.02), and ex vivo clot lysis time increased from 60.6 (55.6-67.4) to 76.0 (69.7-95.0) minutes during THST (p < 0.01). PAP levels reduced from 266.5 (211.8-312.0) to 192.0 (161.0-230.0) μg/L during THST (p < 0.01); other markers of in vivo activation of coagulation remained unaffected. Conclusions: During THST-induced hyperthyroidism, a shift toward a more hypercoagulable and hypofibrinolytic state occurred. However, in vivo activation of hemostasis did not increase. The rise in CRP levels suggests the presence of a low-grade inflammation in patients during THST. Both a hypercoagulable and hypofibrinolytic state and a low-grade inflammation are associated with an increased risk of cardiovascular diseases (CVD). Therefore, the subtle changes found during THST could potentially play a role in the pathogenesis of CVD as observed in DTC patients. Clinical Trial Registration: This study is part of a larger clinical trial registered at the Netherlands Trial Register (NTR ID 7228).

Thrombodynamics as a tool for monitoring hemostatic disorders in patients with chronic glomerulonephritis complicated by nephrotic syndrome.

To assess hemostatic disorders in CGN patients complicated by NS using the thrombodynamics test. The study included 60 adult patients with chronic glomerulonephritis (CGN), mean age 37 years, 31 (52%) women, and 29 (48%) men. Among all patients, 53 % of patients had NS, 47 % had no sign of NS. Hemostasis was assessed using the thrombodynamics test. The results were compared with biochemical parameters, which are usually associated with NS and renal dysfunction. According to the thrombodynamics test, CGN patients with NS demonstrated a tendency to hypercoagulability: increased rates of V (rate of clot growth), increased D (clot density), and increased CS (clot size) after 30 minutes. A positive correlation of these parameters with the serum albumin, creatinine levels, and glomerular filtration rate (GFR) indicates the influence of severe NS and renal dysfunction on the hemostasis activation in CGN patients with NS. According to the thrombodynamics test, CGN patients with NS demonstrate increased rates of clot formation, increased clot size after 30 minutes, and increased clot density due to secondary hemostasis activation. These changes positively correlate with the severity of hypoalbuminemia, hypercholesterolemia, and renal dysfunction in NS patients.

Neutrophil extracellular traps as markers of thromboinflammation in the pathogenesis of female genital tract and breast malignant neoplasms

Introduction. Thrombosis is a formidable complication of the oncological process that still profoundly contributes to overall mortality despite the anticoagulant use. According to the recent data, thrombosis in cancer represents a special type of prothrombotic state, wherein thromboinflammationis one of its constituents. In addition, thromboinflammation contributes both to the disease progression and intensity of metastasis processes. Recently, a large number of studies worldwide have been devoted to investigating thromboinflammation in cancer patients.Aim: to assess NETosis activity (the process of neutrophils extracellular traps synthesis), namely, the concentration of citrullinated histone H3 (citH3) as a blood plasma NETosis marker in women with malignant genital organs and breast neoplasms.Materials and Мethods. The prospective observational controlled non-randomized study included 45 patients (main group) with malignant neoplasms of uterus body, ovaries, cervix (adenocarcinoma of the cervical canal) and mammary glands admitted to the hospital for planned surgical treatment (13, 15, 5 and 13 patients, respectively) and 33 women with benign neoplasms of the genital organs and mammary gland (control group). The plasma citН3 concentration was determined using an enzyme immunoassay.Results. It was found that cancer patients had citН3 concentration significantly increased (1.434–2.058 ng/ml) compared with the control group (0.281–0.371 ng/ml). The concentration of citH3 in patients with tumors of the uterine body and cervix ranged from 2.271 to 2.992 ng/ml, patients with ovarian tumors – from 1.357 to 2.123 ng/ml, patients with breast tumors – from 0.331 to 0.859 ng/ml. The study revealed no significant differences in the citH3 concentration in patients with breast tumors compared to the control group. Upon elevating citН3 concentration, such parameters as C-reactive protein, D-dimer, neutrophils and platelets count, as well as neutrophils/lymphocytes ratio were significantly increased. Significant differences were revealed in platelet count in the main group (236,68–273,77×109/L) vs. control group (178,14–202,35×109/L).Conclusion. The study demonstrated the activation of NETosis in patients with tumors of the uterine body as well as cervix (adenocarcinoma) and ovaries that might be combined with hemostasis activation and systemic inflammatory response.

The portal vein in patients with cirrhosis is not an excessively inflammatory or hypercoagulable vascular bed, a prospective cohort study

BackgroundA hypercoagulable state is not associated with development of portal vein thrombosis in cirrhosis, as we previously demonstrated. However, some groups demonstrated elevated levels of inflammatory markers and activation of hemostasis in the portal vein (PV) compared to posthepatic veins, but because the liver is involved in clearance of these markers, we hypothesize that interpretation of these data is not straightforward. AimTo determine whether the PV has particular proinflammatory/hypercoagulable characteristics by comparing plasma sampled in the PV, hepatic vein (HV), and the systemic circulation. MethodsPlasma samples from 51 cirrhotic patients with portal hypertension undergoing transjugular intrahepatic portosystemic shunt placement, were taken from the PV, HV, and jugular vein (JV). Markers of inflammation (lipopolysaccharide, tumor necrosis factor‐α, interleukin‐6, thiobarbituric acid‐reactive substances), neutrophil‐extracellular‐traps (cfDNA, MPO‐DNA), endothelial damage (von Willebrand factor [VWF]), and hemostasis were determined and compared among the three vascular beds. ResultsMarkers of inflammation were slightly, but significantly higher in the PV than in the HV and systemic circulation. VWF and markers of hemostasis were modestly elevated in the PV. Levels of multiple markers were lower in the HV compared with the PV and systemic circulation. Higher model for end‐stage liver disease score was associated with a more prothrombotic state in all three sample sites. ConclusionIn contrast to published studies, we did not detect a clear proinflammatory or prothrombotic environment in the PV of cirrhotic patients. Many markers are lowest in the HV, indicating that the low levels of these markers in the HV, at least in part, reflect clearance of those markers in the liver.

Peculiarities of hemostasis in patients with COVID-19

Analysis of the dynamics of different stages of clot formation and its lysis in patients with different COVID-19 severity. We prospectively included 58 patients with COVID-19 (39 patients with moderate disease severity and 18 patients with severe disease) and 47 healthy volunteers as a control group. All participants underwent the assessment of flow-mediated dilation (FMD) of brachial artery, impedance aggregometry, rotational thromboelastometry and thrombodynamics. Von Willebrand factor antigen (vWF:Ag) quantification was also performed in patients with COVID-19. Measurements were repeated on the 3rd and 9th day of hospitalization. Compared to the control group, patients with COVID-19 showed reduced values of platelet aggregation and greater values of the clot growth rate, as well as its size and density. On the first day of hospitalization, we found no differences in the activity of plasma hemostasis and endogenous fibrinolysis between subgroups of patients. With the progression of the disease, the growth rate and size of the clot were higher in the severe subgroup, even despite higher doses of anticoagulants in this subgroup. An increase in platelet aggregation was noted during the progression of the disease, especially in the severe subgroup. There were no differences in the results of the FMD test by subgroups of patients. The vWF:Ag level was significantly higher in the severe subgroup. Thus, plasma hemostasis followed by secondary platelet activation correlates with the severity of COVID-19. Patients with moderate to severe coronavirus infection have predominantly local rather than generalized endothelial dysfunction.

Evaluation of hemostasis disorders using the thrombodynamic test in patients with chronic glomerulonephritis with nephrotic syndrome

Nephrotic syndrome (NS) is accompanied by a risk of thrombotic complications due to hypercoagulability. Routine laboratory tests are not sensitive enough to detect these disorders, and therefore the use of integral coagulation tests, including a new thrombodynamic test (TT) in patients with NS, is of high relevance. Using a TT to determine hemostasis disorders in patients with chronic glomerulonephritis (CGN) with NS. The study included 49 patients with CGN, mean age 37 years, of which 25 (51%) women and 24 (49%) men. Of all the examined patients, 20 (40.8%) of people had NS, 29 (59.2%) had no NS. The process of clot formation was assessed by TT. According to TT, 30% (6/20) of patients with NS and 13.7% (4/29) of patients without NS have hypercoagulation with changes in parameters that go beyond the reference values. In patients with NS, an increase in clot density (D), clot formation rate (V) and clot size (CS) was found, especially when albumin decreased below 25 g/l. Negative correlations were found between the levels of albumin, creatinine and clot density (D), which reflects the level of hyperfibrinogenemia, the rate of clot formation (V) and the integral index of coagulation (CS). The results indicate mainly the activation of the plasma hemostasis due to the internal coagulation pathway. However, the correlation of Tlag (delay time for the onset of clot formation after contact of blood plasma with the insert-activator) with serum cholesterol levels may also indicate activation of the extrinsic coagulation pathway. In CGN patients with NS, activation of the plasma hemostasis is noted, as evidenced by an increase in the rate of formation (V) and size of the clot (CS) after 30 minutes, as well as the density of the formed clot (D).

Bio‐Inspired Self‐Hydrophobized Sericin Adhesive with Tough Underwater Adhesion Enables Wound Healing and Fluid Leakage Sealing (Adv. Funct. Mater. 32/2022)

Wound Healing In article number 2201108, Zheng Wang, Lin Wang, and co-workers develop a self-hydrophobized adhesive with robust underwater adhesion, resembling a mechanism underpinning the underwater adhesion of mussel foot proteins. This adhesive possesses multiple advantages outperforming commercial adhesives, such as in vivo wound healing-promoting effects, effective fluid leakage sealing, and rapid hemostasis activity.

Platelet augmentation activity of mature leaf juice of Sri Lankan wild type cultivar of Carica papaya L: Insights into potential cellular mechanisms

Ethnopharmacological relevanceCarica papaya L., a common fruit crop of the family Caricaceae and its leaf juice/extract is a traditionally commended preparation against dengue and other thrombocytopenic diseases by many Asian countries. Aim of the studyThe present study posits the potential cellular mechanisms of platelet augmentation activity of mature leaf juice of Sri Lankan wild-type Carica papaya. Materials and methodsC. papaya leaf juice prepared from different cultivar types, maturity of the leaf, agro-climatic region, and preparation methods were orally administered to hydroxyurea-induced thrombocytopenic rats at 0.72 ml/100 g BW dosage to investigate the most potent platelet increasing preparation.The papaya juice doses; low dose (LD-0.18 ml/100 g BW), human equivalent dose (HED-0.36 ml/100 g BW), and high dose (HD-0.72 ml/100 g BW), were administered to thrombocytopenic rats (N = 6/group) daily for three consecutive days and post-treatment plasma levels of interleukin 6 (IL-6), thrombopoietin (TPO), and platelet-activating factor (PAF) were quantified using specific rat ELISA kits. The mature leaf juice of C. papaya induced IL-6 secretion from bone marrow cell (BMC) cultures was quantified using ELISA. The ability of papaya juice to protect the platelet membrane, from the damage caused by the lytic agent was analyzed in vitro using the lactate dehydrogenase (LDH) assay. The effect of the mature leaf juice of C. papaya on secondary hemostasis was investigated using blood coagulation and clot hydrolyzing activity. ResultsThe comparative analysis revealed that the platelet increasing activity of C. papaya leaf did not significantly differ among different types of cultivar, maturity of the leaf, agro-climatic regions and preparation methods (p > 0.05). Both TPO and PAF levels in thrombocytopenic rats diminished when treated with all three doses of the mature leaf juice of C. papaya (p < 0.05), yet IL-6 plasma level was unaltered (p > 0.05). Nevertheless, ex vivo treatment of the mature leaf juice of C. papaya had significantly enhanced IL-6 levels of rat BMC cultures (p < 0.05). Pre-treatment of platelets with the mature leaf juice of C. papaya at different concentrations significantly inhibited LDH leakage from platelets and may have reduced the membrane damage caused by the lytic agent (p < 0.05). Treatment of mature leaf juice of C. papaya also significantly reduced blood clotting time through the extrinsic pathway of the blood coagulation cascade (p < 0.05). Further, prolonged incubation of the plasma clot with different concentrations of the papaya leaf juice revealed dose-dependent hydrolysis of the blood clot, indicating fibrinolysis activity. ConclusionsThe current study exceeded the traditional medicinal claims, and scientifically affirmed the platelet augmentation activity of mature leaf juice of C. papaya. The mechanistic rationale tested herein explicated that the platelet augmentation activity of the papaya leaf juice can be partially attributed to the stimulation of bone marrow megakaryocytes via modulating thrombopoietic cytokines TPO and IL-6, and by inhibiting the secretion of PAF, while reducing the peripheral platelet destruction by stabilizing the platelet membrane. Further, mature leaf juice of C. papaya imparted both pro-coagulation and fibrinolysis activity of secondary hemostasis endorsing its potential against thrombocytopenia.

Markers of hemostasis activation and endothelial damage in patients with active cancer

Introduction. Increased expression of tissue factor by tumor cells, formation of procoagulant microparticles and secretion of proinflammatory cytokines that activate leukocytes and endothelial cells are considered to be the main factors provoking blood coagulation activation in cancer patients.The aim of the investigation was to study the peculiarities of hemostasis activation markers and endothelial damage in patients with active cancer.Materials and methods. Patients with active cancer were included in the study. We determined the following biomarkers: fibrinogen (Fg), von Willebrand factor (vWF), D-dimer (D-d), growth differentiation factor 15 (GDF-15), vascular endothelial growth factor A (VEGF-A).Results. Twenty-two patients with active cancer were included in the study. The median follow-up of the patients was 180 days (minimum 90, maximum 240). The presence of metastatic lesion was found in 62% of patients. At the end of the follow-up period (after 6 months) remission of the underlying disease was observed in 45.5% of patients, and 54.5% of patients were found to have progressed oncoprocess. GDF-15 levels ranged from 1486 to 11,722 pg/ml and were above normal values in all patients. Significant variability was also revealed in the level of VEGF-A - from 1 to 2944 pkg/ml, and only in 7 (32%) patients its level corresponded to normal values (0-66 pkg/ml). High levels of Fg (&gt;3.6 g/L), D-d (&gt;500 ng/ml), and vWF (&gt;160%) were detected in 19 (86%), 18 (82%), and 17 (77%) patients, respectively.Conclusions. The pilot study demonstrates a pronounced activation of the blood coagulation system and endothelial damage in patients with active cancer receiving chemotherapy and having a high risk of venous thromboembolic complications. The detected relationship of markers characterizing blood coagulation activation (D-d) and endothelial damage (vWF) with the progression of oncoprocess necessitates their further study in this category of patients.

P1680: INFLUENCE OF D-DIMERS ON THROMBOEMBOLIC RISK IN PATIENTS WITH SARS-COV-2 IN AN INTENSIVE CARE UNIT

Background: Patients with COVID-19 have a higher incidence of thromboembolic events (TE) probably due to endothelial injury caused by the binding of SARS-CoV-2 to the ACE-2 receptors. The current literature showed that these patients have a tendency to a procoagulation state, and D-dimers (D-d) may be a global marker of hemostasis activation. In this way, the increase in D-d levels prompted the need to assess them at hospital admission and start anticoagulation (AC) prophylaxis, especially in intensive care unit (ICU) hospitalizations. Further, there is no consensus about the levels of D-d that could predict new TE. Aims: This study intends to determine whether D-d levels at hospital admission are related with an increased risk for TE during ICU hospitalization and determine an eventual cut-off level that could predict the risk of these events. Methods: Retrospective, observational, single-center study of patients with an established diagnosis of COVID-19, who underwent hospitalization in the ICU of a tertiary care hospital between December 2020 and January 2021. Clinical, analytical and demographic data were collected through clinical medical records. The data analysis was executed using IBM SPSS Statistics 28. To evaluate the predictive value of D-d on TE risk and survival in patients at ICU admission, a logistic regression and a ROC analysis were performed. Results: A total of 116 patients were included, 38 (32.8%) females and 78 (67.2%) males, with a median age of 62 (27-86) years old, 15 (12.9%) of them with a previous AC therapy. The mean number of days spent in the ICU was 16 (13-18) days. Out of the 116 patients, 46 (39.7%) patients passed away during ICU stay and 17 (14.7%) patients presented with thromboembolic events (2 of them with 2 TE). Out of the 19 total TE, there were 8 (42.1%) deep vein thrombosis, 3 (15.8%) pulmonary embolisms, 3 (15.8%) arterial strokes, 3 (15.8%) upper limb infarctions and 1 (5.3%) myocardial infarction. The logistic regression model shows that the D-d levels at ICU admission are statistically significant on the likelihood to have TE (χ2(2)=9.089, p=.011). The model explained 13.9% (Nagelkerke R2) of the variance in TE and correctly classified 86.1% of cases. Increasing levels of D-d at an ICU admission were associated with a slightly increased likelihood of exhibiting those events (relative risk=1.000051750). Another logistic regression was performed to evaluate whether D-d levels at ICU admission influenced prognosis (survivor vs non-survivor), however we didn´t find any differences statistically significant (p=0.727). Furthermore, the ROC analysis executed to determine the cut-off D-d level at ICU admission that would better predict the TE determined a value of 763.5 ng/mL with a sensibility of 76.5% and a specificity of 63.7%. Summary/Conclusion: D-d levels at ICU admission are a risk factor to account for on the likelihood of future TE on COVID-19 patients, although the relative risk is low. Despite the lack of consensus for predicting D-d levels, our results suggest that D-d values, at ICU admission, can be predictive of future TE. In spite of this finding, D-d levels at admission are not correlated to survival. At the moment, despite AC therapy during ICU stay, there were still patients with TE, which means that the current prophylaxis isn’t totally effective. Further investigation is needed to establish criteria for an upgraded AC, for a lower ICU stay time and to improve the prognosis.

Diagnosis of asymptomatic bone metastases from breast cancer.

e13042 Background: The purpose of this study was to analyze the prognostic value of blood levels of fibrinogen (F) in bone metastases from breast cancer (BC). Methods: The study included 160 patients with nodular BC pT2-3N0-1M0-1, including 48 patients in a prospective group (PG) and 112 patients in a retrospective group (RG). All patients underwent initial clinical and laboratory examinations, including determination of alkaline phosphatase (AP) activity (Cobas Integra 4000 plus, Switzerland) and parameters of coagulation hemostasis (STA Compact, France). Bone scintigraphy was performed for complaints of bone pain and/or in cases of elevated AP activity, regardless of SXCT data. Results were considered statistically significant at p &lt; 0.05. Results: Patients in PG were divided into two subgroups depending on F levels: in 31 (64.6%) patients F = 3.67±0.5 g/L, insignificantly exceeding the norm (2.8±0.3 g/L); in 17 (35.4%) patients F = 6.9±0.3 g/L, being 1.9 and 2.5 times (p &lt; 0.05) higher than in subgroup 1 and the norm, respectively. AP activity exceeded the norm by 26% and 40%, respectively (p &lt; 0.1). Bone metastases were detected before treatment in 24 (21.4%) women of RG with pain syndrome; all these patients showed increased blood levels of F, on average up to 7.86±0.8 g/L, similarly to patients in subgroup 2 of PG. F levels in other 88 (78.6%) patients in RG were 3.4±0.6 g/L. The nature and severity of AP changes in RG patients and in both PG subgroups were similar. Initially elevated F levels in 17 PG patients remained unchanged after antitumor treatment (6.2±0.6 g/L). AP activity values were stable after treatment being only 36% and 28% (p &lt; 0.1) higher than the norm, respectively. None of the patients with high F levels complained about bone pain. Unscheduled bone scintigraphy was appointed to 17 patients of PG without clinical symptoms or x-ray (SXCT) signs of pathology but with initially high F which did not decline after treatment. Bone scintigraphy showed metastases to the spine and pelvic bones in 12 of 17 (70.5%) patients 1 month after treatment, subsequently confirmed by MRI results. Conclusions: Initial levels of F within 6.9±0.6 g/L which do not decline after the special treatment allow predicting unfavorable BC course and the presence of metastases to the spine and/or pelvic bones without clinical signs of progression. The proposed method allows diagnosis of advanced tumor process in the absence of clinical signs of the disease with an accuracy of 87.8%, and allows timely corrections to the treatment plan.

Role of Plasminogen Activation System in Platelet Pathophysiology: Emerging Concepts for Translational Applications.

Traditionally, platelets have been exclusively considered for their procoagulant and antifibrinolytic effects during normal activation of hemostasis. Effectively, activated platelets secrete coagulation factors, expose phosphatidylserine, and promote thrombin and fibrin production. In addition to procoagulant activities, platelets confer resistance of thrombi to fibrinolysis by inducing clot retraction of the fibrin network and release of huge amounts of plasminogen activator inhibitor-1, which is the major physiologic inhibitor of the fibrinolytic cascade. However, the discovery of multiple relations with the fibrinolytic system, also termed Plasminogen Activation System (PAS), has introduced new perspectives on the platelet role in fibrinolysis. Indeed, the activated membrane surface of platelets provides binding sites on which fibrinolytic enzymes can be activated. This review discusses the evidence of the profibrinolytic properties of platelets through the description of PAS components and related proteins that are contained in or bind to platelets. Our analyses of literature data lead to the conclusion that in the initial phase of the hemostatic process, antifibrinolytic effects prevail over profibrinolytic activity, but at later stages, platelets might enhance fibrinolysis through the engagement of PAS components. A better understanding of spatial and temporal characteristics of platelet-mediated fibrinolysis during normal hemostasis could improve therapeutic options for bleeding and thrombotic disorders.

Bio‐Inspired Self‐Hydrophobized Sericin Adhesive with Tough Underwater Adhesion Enables Wound Healing and Fluid Leakage Sealing

AbstractGiven that adhesion‐resistance of water severely weakens the bonding strength of tissue adhesives, instant adhesion to wet biological tissue surfaces remains challenging. Inspired by the robust underwater adhesion of natural creatures (such as mussels and barnacles whose underwater adhesion derives from the synergy of hydrophobic and adhesive matrix), a self‐hydrophobized adhesive is developed by co‐assembly of disulfide‐bond hydrolyzed hydrophobic natural sericin protein (a major component of silkworm silk fibers) and tannic acid. Once exposed to water, the self‐aggregation of hydrophobic chains within the adhesive repels water and enhances interfacial hydrogen bonding or electrostatic interactions, mechanistically leading to a robust (&gt;0.5 MPa for solid plates and &gt;0.1 MPa for tissues) and durable (still maintained at 0.4 Mpa even after five cycles) underwater adhesion. Owing to its robust underwater adhesion property, this adhesive possesses multiple advantages outperforming commercial adhesives, such as in vivo wound healing‐promoting effects, effective fluid leakage sealing, and rapid hemostasis activity. This study not only offers a novel strategy for designing and fabricating an underwater adhesive with natural protein but also provides a new adhesive for various potential applications, including promoting wound healing and hemostasis.

Correlation of laboratory markers of hemostatic system activation with concentration and size of plasma extracellular microparticles in patients with COVID-19

Introduction. In recent years, much attention has been paid to the study of extracellular microparticles (microvesicles and exosomes) and their role in the pathogenesis of human diseases.The objective of this study was to determine the number and size of plasma extracellular microparticles (PEMP) in patients with severe and extremely severe COVID-19 and correlate these data with the markers of hemostasis activation, inflammation, and tissue damage.Methods and Materials. The study included 29 patients with severe and extremely severe COVID-19. Concentration and size of PEMP were determined by nanoparticle trajectory analysis (NTA). All patients underwent the complete blood count and the thromboelastometry (TEM). Hemostatic, biochemical, and immunological parameters were assessed including fibrinogen, prothrombin time, activated partial thromboplastin time, D-dimer, C-reactive protein, lactate dehydrogenase, procalcitonin, von Willebrand factor antigen, interleukin 6, and interleukin 18.Results. There were 14 patients (48.3 %) discharged from the ICU with improvement (group 1— survived patients), and 15 patients (51.7 %) with lethal outcomes (group 2 — lethal outcome); the PEMP concentration did not differ between these groups. In group 2, there were heterogeneity of PEMP population, and a tendency to the larger PEMP size (p=0.074). In all patients, the PEMP concentration correlated negatively with both prothrombin time and the number of large platelets; the size of PEMP correlated negatively with the level of von Willebrand factor antigen, and positively with the fibrinogen. In group 1, the PEMP concentration had a direct correlation with both the level of interleukin 18 and maximum clot lysis in TEM; the PEMP size had a direct correlation with the maximum clot lysis in TEM and an inverse correlation with both the level of procalcitonin and maximum clot density in TEM.Conclusion. Our study confirms the importance of the process of extracellular microparticles formation in the COVID-19 pathogenesis. Our findings are consistent with the hypothesis that the parameters of PEMP population can be predictive biomarkers of the COVID-19 severity.