Hemostasis Processes Research Articles

Bleeding Risk Assessment By Sonoclot in Severe Immune Thrombocytopenia

Patients of Immune Thrombocytopenia (ITP) are at increased risk of bleeding and the risk increases with decreasing platelet count. Although in patients of severe ITP (platelet < 30x109/L), the risk of bleeding is the highest yet not all patients bleed. If bleeders and non-bleeders in severe ITP can be reliably differentiated, the financial, physical and social burden can be significantly reduced. However, the available investigations have not been able to serve this purpose. Therefore, we included sonoclot; a global test of coagulation, as a tool to assess the risk of bleeding in ITP. Sonoclot coagulation and platelet function analyser uses viscoelastometry to measure coagulation. It provides information on the haemostasis process, including coagulation, fibrin gel formation, fibrinolysis, and is also able to assess platelet function. The sonoclot also has advantage of ability to measure platelet function in severe thrombocytopenia. It is a portable machine, which can be used as bedside tool in emergency out patient department (OPD) or for admitted patients.The study was conducted at department of internal medicine, postgraduate institute of medical education and research, Chandigarh, India. In this prospective observational study, a total of 80 patients of severe ITP (newly diagnosed) with or without active bleeding were included. Fifty of them had no evidence of any bleeding (Non-Bleeder Group) while thirty of them had features of (WHO grade ≥2) bleeding (Bleeder Group). All these patients were clinically evaluated and samples were collected as per unit protocol for ITP. They were evaluated with Hess test, bleeding time (BT), clotting time (CT), prothrombin time (PT), activated partial thromboplastin time (aPTT), and sonoclot signature analysis. For sonoclot; fresh blood samples were drawn in citrated vaccutainer and analysed by sonoclot coagulation and platelet function analyser made by Sienco, Inc, model SCP1, made in USA. The sonoclot signature assessment gives value for activated clotting time (ACT), clot rate (R1) and platelet function (PF).Both the groups were matched in terms of patient age and all had same diagnosis. The mean and standard deviation for variables were as in Table 1. The difference between platelet counts in two groups was non significant (p=.816). The difference between two groups when compared with Hess test (p=.21, INR (p=.794), bleeding time (p=.051) and clotting time (p=.058) was non-significant. However, significant difference in two sonoclot parameters was observed between two groups. ACT was significantly longer in the bleeders compared to non-bleeders (p=.009) and the platelet function measured by sonoclot signature analysis (depicted by R3) was significantly lower in the bleeders than the non-bleeders (p=.01) (Figure 1 and Figure 2). The clot rate (R1) was non-significantly lower in the bleeders.Although conventional evaluation tools like hess test, bleeding time, clotting time and INR could not differentiate between bleeders and non-bleeders in severe ITP, the coagulation and platelet function parameters assessed by Sonoclot coagulation and platelet function analyser were significantly different between bleeders and non-bleeders. Sonoclot also offers ease of use as compared to other global tests of coagulation (TEG/ ROTEM). Therefore, we conclude that to predict risk of bleeding in severe ITP patients; to help clinician in being more conservative in management of severe ITP patients with low risk of bleeding and avoid unnecessary therapy, sonoclot signature analysis is a handy outpatient or bedside tool. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Viscoelastic tests in liver disease: where do we stand now?

Hemostasis is a complex physiological process based on the balance between pro-coagulant and anticoagulant systems to avoid pathological bleeding or thrombosis. The changes in standard coagulation tests in liver disease were assumed to reflect an acquired bleeding disorder, and cirrhotic patients were considered naturally anticoagulated. In the light of the new evidence, the theory of rebalanced hemostasis replaced the old concept. According to this model, the hemostatic alteration leads to a unique balance between pro-coagulant, anticoagulant, and fibrinolytic systems. But the balance is fragile and may prone to bleeding or thrombosis depending on various risk factors. The standard coagulation tests [INR (international normalized ratio), platelet count and fibrinogen] only explore parts of the hemostasis, not offering an entire image of the process. Rotational thromboelastometry (ROTEM) and thromboelastography (TEG) are both point of care viscoelastic tests (VET) that provide real-time and dynamic information about the entire hemostasis process, including clot initiation (thrombin generation), clot kinetics, clot strength, and clot stability (lysis). Despite prolonged PT/INR (international normalized ratio of prothrombin time) and low platelet counts, VET is within the normal range in many patients with both acute and chronic liver disease. However, bleeding remains the dominant clinical issue in patients with liver diseases, especially when invasive interventions are required. VET has been shown to asses more appropriately the risk of bleeding than conventional laboratory tests, leading to decrial use of blood products transfusion. Inappropriate clotting is common but often subtle and may be challenging to predict even with the help of VET. Although VET has shown its benefit, more studies are needed to establish cut-off values for TEG and ROTEM in these populations and standardization of transfusion guidelines before invasive interventions in cirrhotic patients/orthotopic liver transplantation.

Hemostasia en fístulas arteriovenosas: comparación de la presión manual con la ejercida por un dispositivo regulable

Background and objectivesTo evaluate the pressure generated by an adjustable hemostasis clamp on arteriovenous fistulas (AVF) during the hemostasis proccess, and compare it with the direct two-finger pressure applied by the patient. To evaluate the variations of the direct two-finger pressure along the hemostasis process. MethodsWe analyzed data obtained in 51 hemodialysis procedures from 15 patients. AVF intra-access pressure was used as indirect indicator of the pressure generated by both methods. It was recorded before venous needle removal (PBasal), at clamp application (P1), after clamp adjustement by a nurse (P2), at the beginning of the direct two-finger pressure by the patient (M0), after 3min of two-finger pressure (M3) and after 6min of two-finger pressure (M6). ResultsIntra-access pressure was lower with the adjusted clamp (P2) than with the direct two-finger pressure by the patient (M0) (variation of −18.57%, 95%CI: −14.09 to −4.77mmHg, P<.001). Intra-access pressure generated by the direct two-finger pressure method showed a decreasing trend along the hemostasis process (M3-M0: −8.82mmHg, P<.001; M6-M0: −12.55mmHg, P<.001). ConclusionAn adjustable fistula arm clamp generates a lower pressure in AVF than the direct two-finger pressure applied by the patient. The latter showed a decreasing trend along the hemostasis process. These data suggest that some of the recommendations from clinical guidelines could be based on inaccurate premises.

Trauma magnitude of the meta-epyphyseal cancellous affects the incidence of deep vein thrombosis. A prospective cohort study on the dynamic of Collagen I, Collagen IV, Tissue factor, P-Selectin and Nitric Oxide in the thrombus formation following hip and knee surgeries

IntroductionThe purpose of this study was to analyze the traumatization degree of meta-epiphyseal cancellous of hip and knee joints in major orthopedic surgery that affects the incident of deep vein thrombosis (DVT) event through the dynamics expression of pro-thrombogenic biomarkers (Collagen I, Collagen IV, Tissue Factor, P-selectin) and anti-thrombogenic (Nitric Oxide). MethodsIn this cohort prospective study, there were sixty-nine (69) subjects that were divided into three (3) groups, with twenty-three (23) subjects that were treated with total arthroplasty (TA), twenty-two (22) subjects were treated with hemiarthroplasty (HA), twenty-four (24) subjects were treated with open reduction internal fixation (ORIF). Subjects from May 2010 to September 2011 who met the inclusion criteria were included in this study. All patients were treated without thromboprophylaxis. Blood samples were taken in three different periods, before surgery, 72 h, and 144 h after surgery, for examination of pro-thrombogenic biomarkers (Collagen I, Collagen IV, Tissue Factor, P-selectin) and anti-thrombogenic (Nitric Oxide), which are the components involved in the hemostasis. ResultsDVTs were proven by venography (or Doppler ultrasound in 8 cases) done at 144 h after the surgeries. Eighteen (18) subjects had DVT (26.1%), with ten (10) subjects from the TA group (43.5%), five (5) subjects from the HA group (22.7%), and three (3) subjects from ORIF groups (12.5) %). The risk for experiencing DVT on TA is 3.5 times more than the ORIF group, while in HA group is 2.1 times more than ORIF group. The role of biomarker levels on DVT incidence was found in Col I (p < 0.1) and NO (p < 0.05) at 72 h after surgery. ConclusionThis research confirms that trauma magnitude of the meta-epiphyseal cancellous of hip and knee joints in major orthopedic surgery influences the incidence of DVTs, through the elevation of Col I and NO. An estimated 72 h after surgery is a useful period to examine these biomarkers to help predict the diagnose of DVT. The involvement of the other biomarkers studied (Col IV, TF, and Ps) could not be proven. Future studies are needed to evaluate other biomarkers in the complex process of hemostasis to establish the diagnose of DVT.

Current Promising Biomarkers and Methods in the Diagnostics of Antiphospholipid Syndrome: A Review.

Antiphospholipid syndrome (APS) is a hypercoagulation condition associated with the incidence of heterogenic antiphospholipid antibodies (aPLs), which non-specifically affect hemostasis processes. APS is clinically manifested by recurrent arterial and venous thromboses and reproduction losses. The aPL antibodies, which may induce clinical manifestations of APS, include criteria antibodies anti-cardiolipin, anti-β2-glycoprotein-I, and lupus anticoagulant, but also non-criteria antibodies, for example anti-β2-glycoprotein-I domain I, anti-phosphatidylserine/prothrombin, anti-annexin V, and many others. APS occurs mostly in patients of younger and middle age, most frequently in females. Laboratory diagnostics of APS are quite difficult, as they include a wide spectrum of examining methods, which are based on various principles of detection and are performed using various laboratory techniques. The objective of the review is to describe the current state of potentially examined biomarkers and methods in APS diagnostics. The aforementioned biomarkers are lupus anticoagulant, anti-β2-glycoprotein-I, anti-cardiolipin, anti-β2-glycoprotein-I domain I, anti-phosphatidylserine/prothrombin, anti-β2-glycoprotein-I IgA, anti-cardiolipin IgA, anti-annexin V and II, anti-prothrombin, anti-cardiolipin/vimentin, anti-protein S/protein C, and antibodies against phospholipid antigens for whose diagnostics we may use some of the methods established for a long time and some of the modern methods—the coagulation method for the determination of lupus anticoagulant (LA), enzyme-linked imunosorbent assay (ELISA), chemiluminescence analysis (CLIA), multiplex fluorescence flow immunoassay (MFFIA), fluorescence enzyme immunoassay (EliA), line immunoassay (LIA), multiline dot assay (MLDA), and thin-layer chromatography (TLC). Conclusion: Antibodies against phosphatidylethanolamine, phosphatidic acid, phosphatidylserine, phosphatidylinositol, cardiolipin/vimentin complex, and annexin V are currently the most studied new markers. However, these assays have not been standardized until now, both from the laboratory and clinical point of view. In this review we summarize the evidence of the most studied aPL markers and their potential clinical significance in seronegative APS (SN-APS).

In-silico Studies and Synthesis of 1,3-benzoxazine Derivatives as Antimalarial Agent through PfATP4 Receptor Inhibition

The aims of this research is to study in-silico and synthesize of 1,3-benzoxazine derivatives as an antimalarial agent. These compound was predicted to inhibit the growth of Plasmodium sp. by inhibiting the PfATP4 receptor. The PfATP4 receptor is a receptor from Plasmodium sp. which regulates the process of hemostasis from sodium ions. Mocelular docking study was performed using Molegro Virtual Docker (MVD) version 5.5 on the active site of PfATP4 receptor (PDB ID 2DQS) compared to the rerank score of its native ligand. The synthesis method of 1,3-benzoxazine derivatives has been obtained more effective and efficient by microwave irradiation. Some of 1,3-benzoxazine derivatives had ranges of rerank score from -91.22 to -74.55 kcal/mol which were lower than its native ligand. To continue on the antimalarial activity study, it is necessary to synthesize the compounds. From the results of the in-silico study and the method development of synthesis of 1,3-benzoxazin derivatives, it is expected that further research can be carried out in vitro study on erythrocyte cells infected with Plasmodium sp.

Hemostatic strategies for uncontrolled bleeding: A comprehensive update.

Uncontrolled bleeding remains the leading cause of morbidity and mortality across the entire macrocosm. It refers to excessive loss of blood that occurs inside of body, due to unsuccessful platelet plug formation at the injury site. It is not only limited to the battlefield, but remains the second leading cause of death amongst the civilians, as a result of traumatic injury. Startlingly, there are no effective treatments currently available, to cater the issue of internal bleeding, even though early intervention is of utmost significance in minimizing the mortality rates associated with it. The fatal issue of uncontrolled bleeding is ineffectively being dealt with the use of pressure dressings, tourniquet, and surgical procedures. This is not a practical approach in combat arenas or in emergency situations, where the traumatic injury inflicted is deep inside the body, and cannot be addressed externally, by the application of topical dressings. This review focuses on the traditional hemostatic agents that are used to augment the process of hemostasis, such as mineral zeolites, chitosan based products, biologically active agents, anti-fibrinolytics, absorbable agents, and albumin and glutaraldehyde, as well as the micro- and nano-based hemostatic agents such as synthocytes, thromboerythrocytes, thrombosomes, and the synthetic platelets.

A microfluidic bleeding model to investigate the effects of blood flow shear on microvascular hemostasis

Hemorrhage is the phenomenon of blood loss caused by vascular trauma or other pathological reasons, which is life-threatening in severe cases. Because microhemorrhage is difficult to visually monitor and pre-treat in vivo, it is necessary to establish in vitro prediction methods to study the hemostasis mechanism in different physiological environments. In this study, a microfluidic bleeding model was developed to investigate the effect of blood flow shear on microvascular hemostasis. The results indicated that the regulation of blood shear rate on platelet aggregation affected the growth and morphology of hemostatic thrombus, and finally regulated the process of hemostasis. This in vitro model is significant to studies on hemostatic mechanisms, a reliable prediction of microhemorrhages, and an adjustment of the treatment scheme.

Admitting UnKnown Biosimilar- Drugs Affects Thrombosis and Haemostasis Processes

Admitting UnKnown Biosimilar- Drugs Affects Thrombosis and Haemostasis Processes

Hemostasis – compendium for students

Hemostasis is one of many well-known systems that ensure a constant conditions of the organism's internal environment. This process is usually divided into two main stages: coagulation and fibrinolysis. Both of them occur simultaneously and under physiological conditions they are in dynamic equilibrium. There are primary and secondary hemostasis. The primary hemostasis leads to the formation a platelet clot that forms almost directly after a blood vessel has been ruptured. In the other hand, the secondary hemostasis is the activation of coagulation, which leads to the strengthening of the platelet plug through the fibrin network formation as a result of the polymerization of the soluble plasma protein fibrinogen. The key role in hemostasis plays the interaction of platelets – which are the smallest non nucleated blood cells that are formed from the cytoplasm of megakaryocytes, and plasma coagulation factors with vascular endothelial cells and subendothelial tissues. In this report it is decribed the process of physiological hemostasis, especially the newer concept of blood coagulation.

Fibrinogen level at hospital admission after multiple injury correlates with BMI and is negatively associated with the need for transfusion and early multiple organ failure

IntroductionBleeding and coagulopathy are leading causes of morbidity and lethal outcome after multiple injuries. The pathophysiology of traumatic coagulopathy is under extensive investigations and recent results highlighted the central role of fibrinogen and the fibrin polymerisation process. Our goal was to investigate the factors influencing fibrinogen level and the consequences of hypofibrinogenaemia with clinical importance. MethodsWe conducted a retrospective analysis enrolling adult patients admitted to the shock room of a tertiary trauma centre in Hungary. Beside coagulation values, demographic data, injury related, transfusion and outcome parameters were collected from the hospital electronic charts. Only patients with complete e-chart were involved into final analysis. Multivariate linear and proportional odds logistic regression models were used to model outcomes – admission fibrinogen and SOFA score – controlling for age, sex, BMI, ISS and lactic acidosis. Results54 patients were enrolled in final analysis. Among the parameters analysed, BMI was positively associated with fibrinogen level at admission (+0.23 g/l for every 5 unit of increase in BMI, 95% CI: 0.09-0.37, p=0.0021). Increased risk of transfusion was observed, if fibrinogen at admission was about 1.8 g/l or lower. Beside age and ISS, fibrinogen concentration was also a determinant of early organ failures as it negatively correlated with SOFA scores within 24 hours or care (OR=2.42, 95% CI: 1.05-5.62, for 1 g/l decrease, p=0.0388). ConclusionsIn our trauma cohort BMI seems to significantly influence fibrinogen level at admission. This result draws our attention to the possible differences of haemostasis process, and consequently different diagnostic and therapeutic thresholds in the management of obese trauma patients. Moderate hypofibrinogenaemia increases transfusion risk and beside ISS might be a prognostic factor of early MOF after multiple injuries.

Selatogrel, the reversible and specific P2Y12 receptor antagonist, does not interfere with haemostasis

Abstract Background Combination of a P2Y12 receptor (P2Y12R) antagonist (clopidogrel, prasugrel, ticagrelor) with aspirin is the recommended standard of care for patients with acute coronary syndrome. Selatogrel is a reversible and potent antagonist of P2Y12R. Interestingly, in an experimental thrombosis model in rat, at equivalent antithrombotic effect, blood loss was lower in the presence of selatogrel, compared with clopidogrel or ticagrelor. Purpose To characterise the lower risk of bleeding previously observed with selatogrel Methods Mechanistic studies were performed to profile laser-induced thrombosis in wild-type and P2Y12 deficient mice with real-time intravital microscopy. Ticagrelor and clopidogrel were used as selatogrel comparators. Results Selatogrel, ticagrelor and clopidogrel dose-dependently inhibited laser-induced platelet thrombus formation. At maximal antithrombotic effect, only small mural platelets aggregates, corresponding to the haemostatic seals, were present. The phenotype of these haemostatic seals depended on the P2Y12R antagonist used. In the presence of clopidogrel or ticagrelor, the stability of haemostatic seals was reduced. In contrast, in the presence of selatogrel, the apparent stability was not disturbed. Moreover, equivalent antithrombotic dosing regimens of ticagrelor and clopidogrel interfered with laser-induced calcium mobilisation in the endothelium, restricted subsequent neutrophil adhesion and thus reduced fibrin-mediated stabilisation of the haemostatic seals in wild type mice. The effects of ticagrelor were also observed in P2Y12R-deficient mice, indicating that the effects are P2Y12R independent and off-target. In contrast, an equivalent antithrombotic dosing regimen of selatogrel did not interfere with the process of haemostasis in wild-type or P2Y12R-deficient mice. The degree of interference with the stability of the haemostatic seals correlated with the blood loss profile. The dosing regimens of clopidogrel and ticagrelor, corresponding to the equivalent antithrombotic effects, induced a more pronounced increase in blood loss than that observed with selatogrel. Conclusion Our data offer a novel mechanistic explanation for the differences in bleeding risk of clopidogrel, ticagrelor and selatogrel. Clopidogrel and ticagrelor were found to interfere with haemostasis due to off-target activities. In contrast, selatogrel did not interfere with haemostasis in wild-type and P2Y12-deficient mice, inferring that the process of haemostasis, as defined by formation of haemostatic seals, is independent of P2Y12R. In addition, our data emphasize that the absence of interference with haemostasis is paramount to preserve the advantage of P2Y12R antagonism. Funding Acknowledgement Type of funding source: Private company. Main funding source(s): Idorsia Pharmaceuticals Ltd. Allschwil, Switzerland

The correlation of Neutrophil-Lymphocyte Ratio (NLR) and Platelet-Lymphocyte Ratio compared to D-dimer as a diagnostic test in Deep Vein Thrombosis (DVT)

Background: Deep vein thrombosis (DVT) is a blood clot that occurs in the inner veins caused by heart disease, infection, cancer, and prolonged immobilization of the limbs. Neutrophil-Lymphocyte Ratio (NLR) and Platelet Lymphocyte Ratio (PLR) have been known as a marker of the primary hemostasis process related to the inflammatory pathway. This study aims to evaluate the correlation of Neutrophil-Lymphocyte Ratio (NLR) and Platelet-Lymphocyte Ratio compared to D-dimer as a diagnostic test in Deep Vein Thrombosis (DVT)Methods: A cross-sectional approach has been conducted in this diagnostic study at the Sanglah General Hospital by using secondary data from medical records during July 2018-2019. The study sample consisted of 49 patients with suspected DVT originating from a population who met the inclusion and exclusion criteria. The variables assessed in this study were NLR, PLR, and D-Dimer. Data collection and data analysis were performed by SPSS version 17 for Windows.Results: The average age of respondents was 53.10±13.40 years old. Most of the respondents were male (59.20%), having edema in the lower extremity (61.20%), left unilateral laterality (53.10%), and D-Dimer levels ≥ 0,5 µg/ml (76.1%). There was a statistically significant relationship between the average value of NLR (9,07±4,2) and PLR (183,55±66,52) with the occurrence of DVT (P&lt;0.05). The Area Under Curve (AUC) of ROC Analysis was 94.40% (Cut-off: 8.20; p&lt;0.050) in NLR and 92.10% (Cut-off: 159.66) in PLR to the D-Dimer on the incidence of DVT. There was a significant moderate positive correlation between NLR and PLR combination on DVT incidences (r=0.532; p=0.001).Conclusion: NLR and PLR can be used as an alternative to DVT diagnostic tools due to high sensitivity and specificity, easy to use, inexpensive, simple, and widely available in Indonesia.

Hemostasis in sickle cell disease

Sickle cell disease results in a significant morbidity and mortality related to intra-vascular thrombosis. This study is an attempt to improve our understanding the role of hypercoagulability in the pathogenesis of sickle cell disease. A case group of 20 asymptomatic sickle cell adult patients in a steady-state were compared with a control group of 20 normal adult people , both groups aged (18-50) year and from both sex, to evaluate the process of hemostasis. An investigation has been done for both groups including estimation of hemoglobin, platelets count, bleeding time and clotting time. There is a highly significant increase in the number of platelets with (P&lt;0.01) together with a highly significant decrease in bleeding time with (P&lt;0.01) for a case group in comparison with a control group. There is no significant difference of clotting time between both groups. That may suggest that the platelets aggregation formation activity is significantly increase in patients with sickle cell disease in a steady-state.

Monitoring the hemostasis process through the electrical characteristics of a graphene-based field-effect transistor

Graphene-based transistors are promising devices in the evaluation of carrier density in biological analytes. We report on the design and fabrication of a graphene-based field-effect transistor for monitoring and assessing the interaction between the coagulation factors based on the charge carrier density in a blood sample. When biochemical reactions occurred during the coagulation cascade process, a dopant effect was noticed on the graphene surface by the change in Dirac point voltage values. Additional experiments were performed using blood samples treated with activators (vitamin K, calcium chloride, and thromboplastin reagent) and inhibitors (heparin drugs) to evaluate the selectivity of the graphene field-effect transistor devices. Since the transfer characteristic curves presented divergent behaviours for different levels of procoagulants and anticoagulants, the measurements showed that the devices can assess changes in the concentrations of factors that inhibit or accelerate the cascade process when using untreated and treated samples. Reproducibility was verified by testing samples from different sources. To the best of our knowledge, this study is the first to demonstrate the potential of graphene in monitoring the hemostasis process through the analysis of the electrical properties of human whole blood.

Medicinal Plants as Potential Hemostatic Agents.

Medicinal plants with a variety of phytochemical ingredients remain a potential source for new drug discovery. The use of medicinal herbs in a wide range of diseases and symptoms, such as bleeding, is prevalent in traditional and ethno medicine worldwide. Thus, this work provides a comprehensive review of medicinal plants or their isolated compounds, with respect to their ethno-medicinal use, which have demonstrated the stimulating effect on the hemostasis process. The relevant studies were withdrawn from electronic databases including Pubmed, EMBASE and Web of Science with a structured search methodology. The total of 17 medicinal plants with hemostatic activity were extracted. The most frequently studied plant families were Compositae, Lamiaceae, Fabaceae, and Asteraceae. Bioactive compounds exerting hemostatic activity included tannins, iridoid glycosides, glycoconjugate, lignan, saponins and phenolic compounds. The most attributed mechanisms include coagulation stimulation via increasing the factor XII activity and plasma fibrinogen levels, the fibrinolysis inhibition, vascular or smooth muscle constriction and platelet aggregation. The most important adverse effects of high dose extract or isolated compounds administration were hepatotoxicity and nephrotoxicity. This review provides a list of medicinal plants with hemostatic activity that could be used as valuable sources of new plant-based hemostatic agents. Furthermore, this could be practical in detecting possible interactions of plants with anticoagulant, antiplatelet, fibrinolytic and antifibrinolytic medications.

Three-Dimensional Technology: Evaluating the Use of Visualisation in Midwifery Education

Midwifery learning and teaching resources have remained unchanged for decades. At a regional Queensland university, a 3D visualization resource was introduced in addition to books, lectures, and clinical skills laboratory sessions to enhance students' conceptual understanding of the physiological processes related to the birth of the placenta and hemostasis. Fourteen second-year midwifery students volunteered to participate in pilot evaluation. This study included an eight-item questionnaire using Likert scale rankings followed by three open-ended questions, to evaluate the 3D midwifery visualization resource (3DMVR) and its use with midwifery students. All participants believed the 3D visualization resource enabled them to gain a greater depth of understanding about the anatomy and physiology of the uterus and birth of the placenta and understanding of the processes of hemostasis. Research is needed to assess if students' learning and retention of knowledge is improved using this new technology.

GLYPROLINE PEPTIDE PHARMACODYNAMICS IN RATS IN THE SETTING OF METABOLIC SYNDROME BY THE PARAMETERS OF LIPID METABOLISM AND TROMBOELASTOGRAMMA

In this study, experimental data on the biological action of glyproline peptides — Pro-Gly-Pro, Pro-ArgPro, Arg-Pro-Gly-Pro and Pro-Gly-Pro-Leu — on the processes of blood coagulation and lipid metabolism were obtained using animal models of metabolic syndrome. Under the conditions of increased blood clotting and hypercholesterolemia, the regulatory peptides under study were administered intranasally for 7 days once every 24 hours. 20 hours after the last peptide administration, thromboelastogram parameters confi rmed the restoration of the functional state of the coagulating and anticoagulant systems. In addition, a simultaneous positive shift in the parameters of lipid metabolism was observed. These changes lasted for 7 days following the withdrawal of the drugs. It is found that the biological action of the peptides under study consists in their simultaneous regulatory impact on the processes of hemostasis and lipid metabolism.

Biomimetic Anti-Adhesive Surface Microstructures on Electrosurgical Blade Fabricated by Long-Pulse Laser Inspired by Pangolin Scales.

The electrosurgical blade is the most common invasive surgical instrument in a cutting and hemostasis process; however, the blade easily leads to the adhesion of overheated soft tissues on the blades and induces a potential danger for the patients. To minimize the adhesive tissues, we proposed the one-step surface texturing method to fabricate anti-adhesive biomimetic scales on stainless steel 316L rapidly based on the self-organized surface microstructures induced by the long-pulse fiber laser, which was inspired by the excellent performances of anti-adhesion and anti-friction in the pangolin scales. The optimal formation parameters, chemical components, and crystal structures of the laser-induced self-organized surface microstructures were investigated in the experiments. Moreover, the underlying formation mechanism was revealed. The electrosurgical blades with biomimetic scales have hydrophobicity and a smaller frictional coefficient, which effectively reduced the adhesion of soft tissue.

Abnormal Platelet Phenotypes in Patients with Myelodysplastic Syndromes

Background: Hemorrhage and infection are two main causes of death in patients with myelodysplastic syndromes (MDS), mainly due to thrombocytopenia and neutropenia respectively. However, it is becoming increasingly clear that platelet dysfunction can also affect the process of hemostasis and anti-infection. Several studies have evaluated platelet activation in MDS and found platelet dysfunction, but immune-related function of platelets in patients with MDS has not been investigated yet. The aim of this study was to evaluate activation function and immune-related function of platelets in MDS by testing platelet activation-associated phenotypes and immune-associated phenotypes. Methods: We included 29 MDS patients and 22 healthy subjects, and MDS patients were divided into different subgroups (low-risk group and high-risk group; untreated group and treated group; pre-transfusion group and post-transfusion group) according to IPSS-R score, hypomethylating agents (HMAs) therapy and platelet transfusion history to observe phenotype changes under different factors. Platelet light scatter properties, expression of CD41a, expression of activation-associated phenotypes (CD62p and CD63) and expression of immune-associated phenotypes (CD154 and TLR4) were systematically detected by multi-parameter flow cytometry (MFC). Then correlations between phenotypes and clinical indexes were analyzed. Results: Compared to the healthy controls, decreased expression of platelet-specific antigen CD41a was shown in MDS patients (P&lt;0.05). No difference was found in platelet light scatter properties between MDS patients and healthy subjects (P&gt;0.05). Significantly decreased expression frequency and intensity of activation phenotype CD63 were found in patients with MDS (P&lt;0.05). Low-risk MDS showed lower expression frequency while high-risk MDS showed reduced mean fluorescence intensity (MFI) of CD63. Decreased expression of CD154 and TLR4 was found in MDS patients (P&lt;0.05) which was significantly elevated after HMAs therapy (P&lt;0.05). Particularly, high-risk MDS patients again exhibited reduced MFI of CD154 and TLR4 (P&lt;0.05). Correlation analysis showed that the expression of activation-associated phenotypes was not significantly correlated with the severity of bleeding events, but expression of CD62p was negatively correlated with white blood cell count (WBC) (r=-0.496, P=0.006; r=-0.498, P=0.006), absolute neutrophil count (ANC) (r=-0.512, P=-0.005; r=-0.442, P=0.016), fibrinogen (FIB) (r=-0.415, P=0.025; r=-0.510, P=0.005), and D-dimer (DD) (r=-0.547, P=0.002; r=-0.601, P=0.001), and positively correlated with prothrombin time (PT) (r=0.409, P =0.028; r=0.489, P=0.007). Expression of immune-associated phenotypes was not significantly correlated with the severity of infection events (P &gt; 0.05). Conclusion: MDS patients displayed defective expression of both activation- and immune-associated platelet phenotypes, with differential mechanisms between low-risk and high-risk group regarding phenotype alterations. CD62p showed clinical relevance in regard to WBC count and coagulation indexes, and HMAs treatment significantly improved CD154 and TLR4 expression on platelets. Taken together, the findings confirmed impaired platelet phenotypes in MDS which may assist in the diagnosis and identification of MDS patients. Disclosures No relevant conflicts of interest to declare.