Study of the Blood Compatibility of Sulfated Organosolv Lignins Derived from Abies sibirica and Larix sibirica Wood Pulp.

The effects of sulfated organosolv lignins derived from fir (Abies sibirica) and larch (Larix sibirica) (SLf and SLl; 4-3-7.5% sulfur, median-weight molecular mass 2960-4888 Da), on human blood/plasma clotting, platelet aggregation, and erythrocyte hemolysis were studied in vitro. Antithrombin activities of the samples were below 2 U/mg. Specimens of SLf (sulfur content 6.5, 6.6, and 7.5%, molecular weights 3503, 3487, and 3580 Da, respectively) and SLl (4.3 and 6.3%, 2960 and 3497 Da) in a concentration of 0.01 mg/ml did not prolong the blood clotting time, did not provoke human platelet aggregation, did not destroy erythrocyte membranes, and could be used for construction of drug delivery systems. The SLf sample (6.5%, sulfur, 3503 Da) in concentrations from 0.09 to 1.82 mg/ml did not stimulate platelet aggregation, reduced ADP-induced platelet aggregation, and 2-fold prolonged the blood/plasma clotting time 2-fold in comparison with control and could be used for creation of biomaterial with clot-resistant surface.

Influence of the drying method on the bioactive compounds and pharmacological activities of rhubarb.

BACKGROUND: Raw rhubarb samples that have been subjected to different drying procedures will have different therapeutic effects, possibly due to processing-induced variations in the chemical composition. In the present work, the fresh materials were processed by smoking, sun-drying, shade-drying and oven-drying at low, moderate and high temperatures. To facilitate the selection of a suitable drying method for rhubarb, the quality of rhubarb processed under various drying conditions was evaluated based on the simultaneous determination of multiple bioactive constituents in combination with bioactivity assays. RESULTS: The total concentrations of 12 compounds in smoked rhubarb were higher than the concentrations of the same components in raw rhubarb and rhubarb products processed using other drying techniques. Smoked rhubarb was found to substantially inhibit Na+ /K+ -ATPase and thrombin. In addition, higher content of anthraquinones led to higher Na+ /K+ -ATPase inhibitory activities, and higher gallic acid content increased the antithrombin capacity. CONCLUSION: The results confirmed that post-harvest fresh plant materials, especially roots, were still physiologically active organs that could undergo series of anti-dehydration mechanisms, including the production of related secondary metabolites during the early stages of dehydration. Therefore, the proper design of drying processes could enhance the quality of rhubarb as well as other similar medicinal plants. © 2018 Society of Chemical Industry.

An ultrafiltration and high performance liquid chromatography coupled with diode array detector and mass spectrometry approach for screening and characterizing thrombin inhibitors from Rhizoma Chuanxiong.

Thrombin (THR) plays a significant role in thromboembolic diseases, direct THR inhibitors are a class of important clinical anticoagulant drugs. This study established a THR in-solution based biospecific extraction combined with ultrafiltration and high performance liquid chromatography coupled with diode array detector and mass spectrometry analysis (TUA) method to screen and identify ligands for THR in Rhizoma Chuanxiong. After evaluating the reliability of the present TUA method using positive (argatroban) and negative (adenosine, tirofiban, ticagrelor) control drugs, this method was successfully applied to detect eight potential active compounds in Rhizoma Chuanxiong. Two new THR-targeted compounds isochlorogenic acid C and senkyunolide I with high THR inhibitory activity (IC50 206.48 and 197.23µM, respectively) were identified by liquid chromatography/mass spectrometry and enzyme inhibitory activity test finally. They were reported with direct THR inhibition activity for the first time and their ligand-THR interactions were explored by in silico molecular docking research. In addition, based on the TUA screening result, four compounds gained similar structure with the two hit compounds were also investigated as promising candidates targeting THR with high binding energy (>5.0kcal/mol). These results may prove that the proposed method could effectively screen THR inhibitors in complex mixtures.

Non-neoplastic Portal Vein Thrombosis in HCV Cirrhosis Patients: Is it an Immuno-Inflammatory Disorder?

BACKGROUND AND AIMS: Portal vein thrombosis (PVT) is a critical complication in cirrhotic patients. We explored the role of the activated factor VII-antithrombin (FVIIa-AT) complex and enhanced monocytic tissue factor (TF) expression in the development and prediction of non-neoplastic PVT in cirrhotic patients. MATERIAL AND METHODS: A total of 30 HCV-cirrhosis patients were included in our study. They were compared to 35 cirrhotic patients without PVT, 15 non-cirrhotic patients with PVT, and 15 healthy controls. The plasma level of the FVIIa-AT complexes was analyzed by ELISA. MIF CD142, CD86, and HLA-DR on monocytes (CD14) were determined by flow cytometry. RESULTS: Compared with cirrhotic patients without PVT, cirrhotic patients with PVT had comparable plasma values of FVIIa, AT, and the FVIIa-AT complex. However, they had significantly lower values compared to non-cirrhotic patients with PVT and healthy controls. Cirrhotic patients with PVT had increased monocytic TF expression (MIF CD142) compared to non-PVT cirrhotic patients and healthy controls [86.5 (93.5) vs. 18 (32.0) and 11.0 (6.0), respectively; p < 0.001 for each]. However, cirrhosis PVT could not be distinguished from non-cirrhosis PVT. The area under the ROC curve of MIF CD142 was 0.759 (0.641- 0.876; p = 0.000) at an optimal cut-off value of 45, which yielded a sensitivity of 60% and a specificity of 77.1%, as well as a PPV and NPV of 69.2% for each. CONCLUSION: Enhanced expression of monocytic TF may have a role in the development and prediction of non-neoplastic PVT in HCV-cirrhosis patients. Large multicenter studies are necessary to validate our results.

Pharmacokinetics and pharmacodynamics of single doses of rivaroxaban in obese patients prior to and after bariatric surgery.

AIMS: Venous thromboembolism is an important cause of postoperative morbidity and mortality in bariatric surgery. Studies of direct oral anticoagulants (DOACs) are not available in this surgical field. The objective of this phase 1 clinical trial was to investigate pharmacokinetic and pharmacodynamic (PK/PD) parameters of rivaroxaban in bariatric patients. METHODS: In this single-centre study, obese patients received single oral doses of rivaroxaban (10 mg) 1 day prior to and 3 days after bariatric surgery. PK and PD parameters were assessed at baseline and during 24 h after drug ingestion. RESULTS: Six Roux-en-Y gastric bypass patients and six sleeve gastrectomy patients completed the study. Mean rivaroxaban area under plasma concentration-time curve, peak plasma concentration, time to peak plasma concentration and terminal half-life were 971.9 µg·h l-1 (coefficient of variation: 10.6), 135.3 µg l-1 (26.7), 1.5 h and 13.1 h (34.1) prior to and 1165.8 (21.9), 170.0 (15.9), 1.5 and 8.9 (44.6) postsurgery for SG patients and 933.7 µg·h l-1 (22.3), 136.5 µg l-1 (10.7), 1.5 h und 13.8 h (46.6) prior to and 1029.4 (7.4), 110.8 (31.8), 2.5 and 15 (60.0) postsurgery for Roux-en-Y gastric bypass patients, respectively. Prothrombin fragments (F1 + 2) decreased during the first 12 hours and increased thereafter in the pre- and the postbariatric setting. Thrombin-antithrombin complexes dropped within 1-3 h in the prebariatric setting and remained low after surgery until they increased at 24 h postdose. Rivaroxaban was well tolerated and no relevant safety issues were observed. CONCLUSIONS: Bariatric surgery does not appear to alter PK of rivaroxaban in a clinically relevant way. Effective prophylactic postbariatric anticoagulation is supported by changes in PD.

Thrombomodulin improved liver injury, coagulopathy, and mortality in an experimental heatstroke model in mice.

BACKGROUND: Heatstroke is a life-threatening illness and causes high mortality due to multiple organ injuries. Thrombomodulin (TM) is an endothelial anticoagulant cofactor that plays an important role in the regulation of intravascular coagulation. In this study, we investigated the effect of TM on the inflammatory process, liver function, coagulation status, and mortality in experimental heatstroke. METHODS: Male C3H/HeN (8-10 weeks) mice were randomly assigned to the TM-treated group (TG-Pre) or nontreated heatstroke group (HS). In group TG-Pre, mice were treated with recombinant soluble TM (1 mg/kg, intraperitoneally) before heat exposure. In some experiments, recombinant soluble TM was administrated during heat exposure (TG-Delay). Heatstroke was induced by exposure to ambient temperature of 38°C for 4 hours. After heat exposure, the levels of tumor necrosis factor-α, interleukin-6, and plasma high-mobility group box 1 (HMGB1), liver function, plasma aspartate aminotransferase and alanine aminotransferase concentrations, and immunohistochemical and histopathological characteristics of the livers were determined. The coagulation status, plasma protein C levels, and thrombin-antithrombin complex levels were also measured. RESULTS: In group HS, plasma cytokines and HMGB1 concentrations increased after heat exposure. Plasma aspartate aminotransferase and alanine aminotransferase concentrations increased after heat exposure. In group HS livers, strong and extensive immunostaining for HMGB1 was observed. In addition, there was extensive hepatocellular necrosis and collapse of nuclei observed. In group HS, plasma protein C levels were suppressed and plasma thrombin-antithrombin complex levels increased. In group TG-Pre, plasma cytokines and HMGB1 concentrations were suppressed after heat exposure compared with group HS. Liver injury, coagulopathy, and mortality also improved in group TG-Pre. Furthermore, recombinant soluble TM treatment decreased mortality even with delayed treatment. CONCLUSIONS: This study demonstrated that recombinant soluble TM suppressed plasma cytokines and HMGB1 concentrations after heat exposure. Recombinant soluble TM also improved liver injury and coagulopathy. Recombinant soluble TM treatment improved mortality even with delayed treatment. Recombinant soluble TM may be a beneficial treatment for heatstroke patients.

Review article: heparin sensitivity and resistance: management during cardiopulmonary bypass.

Heparin resistance during cardiac surgery is defined as the inability of an adequate heparin dose to increase the activated clotting time (ACT) to the desired level. Failure to attain the target ACT raises concerns that the patient is not fully anticoagulated and initiating cardiopulmonary bypass may result in excessive activation of the hemostatic system. Although antithrombin deficiency has generally been thought to be the primary mechanism of heparin resistance, the reasons for heparin resistance are both complex and multifactorial. Furthermore, the ACT is not specific to heparin's anticoagulant effect and is affected by multiple variables that are commonly present during cardiac surgery. Due to these many variables, it remains unclear whether decreased heparin responsiveness as measured by the ACT represents inadequate anticoagulation. Nevertheless, many clinicians choose a target ACT to assess anticoagulation, and interventions aimed at achieving the target ACT are routinely performed in the setting of heparin resistance. Treatments for heparin resistance/alterations in heparin responsiveness include additional heparin or antithrombin supplementation. In this review, we discuss the variability of heparin potency, heparin responsiveness as measured by the ACT, and the current management of heparin resistance.

Apolipoprotein A-IV as a novel gene associated with polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is a common endocrine-metabolic disorder, affecting 6-10% of women of reproductive age. The etiology remains poorly understood. To investigate the differentially expressed proteins from PCOS patients versus healthy women, the protein expression in follicular fluid was analyzed using two-dimensional electrophoresis (2-DE). Since follicular fluid contains a number of secretory proteins required for oocyte fertilization and follicle maturation, it is possible that follicular fluid can be used as a provisional source for identifying pivotal proteins associated with PCOS. In this study, six overexpressed proteins [kininogen 1, cytokeratin 9, antithrombin, fibrinogen γ-chain, apolipoprotein A-IV (apoA-IV) precursor and α-1-B-glycoprotein (A1BG)] in follicular fluids from PCOS patients were identified with matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF-MS) and nano LC-MS/MS. Western blot analysis confirmed that the protein expression levels of apoA-IV precursor and A1BG were increased in follicular fluid from PCOS patients compared with those from normal controls. The analysis of protein expression for other proteins revealed individual variation. These results facilitate the understanding of the molecular mechanisms of PCOS and provide candidate biomarkers for the development of diagnostic and therapeutic tools.

Changes in platelets and anticoagulant protein activity during adenosine-exercise single-photon emission computed tomography stress test.

INTRODUCTION: Activation of haemostasis during physical stress or during myocardial ischemia could be an important mechanism to trigger coronary and stent thrombosis. We examined changes in haemostatic parameters and its association with myocardial ischemia during adenosine-exercise-SPECT (adeno-EX) stress test in coronary patients at least 4 months after coronary stenting. OBJECTIVE: The aim of this study was to examine relationship between changes in haemostatic parameters and stress induced myocardial ischemia quantified by perfusion scintigraphy in stented coronary patients. METHODS: Thirty-seven patients on dual antiplatelet therapy (26 on clopidogrel plus aspirin and 11 on aspirin only) 4-8 months after successful intracoronary stent implantation were enrolled in the study. We determined the levels of platelet aggregability (PA) on ADP (PA-ADP) and epinephrine (PA-EPI), beta-thromboglobulin, platelet factor-4, protein C (PC) and antithrombin (AT) before and 15 minutes after intravenous injection of 150 micro/kg adenosine for4 minutes concomitant with supine ergo-bicycle exercise test for 50 W. The size of stress perfusion defect was measured 15 minutes after stress and in rest 4 hours later by 99mTc-tetrofosmin single photon emission computed tomography (SPECT) within 17 myocardial segments. RESULTS: There were no differences between haemostatic parameters before and after stress. A significant myocardial ischemia after exercise was registered in 12 patients on combined antiaggregation therapy and in 5 patients on aspirin. In this preliminary report, because of a small number of patients in the aspirin group we did not analyse difference in the levels of haemostatic markers and their correlations with the size of perfusion defect. The only significant difference between measured haemostatic parameters in the patients with stress induced ischemia compared to the patients without it, was a lower level of AT activity after stress (81.0% vs. 87.5%; p = 0.027). Antithrombin activity before stress had significant negative correlation with the size of perfusion defect in rest (R2 = 0.219; p = 0.016) and PC activity before stress had significant linear correlation with stress perfusion defect (R2 = 0.248; p = 0.010). CONCLUSION: Baseline activities of natural anticoagulant proteins AT and PC are associated with the size of myocardial perfusion defect during adeno-EX-SPECT test. Patients with significant stress-induced ischemia had lower levels of AT activity after stress.

Coagulation disturbances in paediatric patients with hepatic veno-occlusive disease after stem cells transplantation.

INTRODUCTION: Hepatic veno-occlusive disease (VOD) is a life threatening complication after stem cells transplantation (SCT). Its prediction, precise diagnosis and treatment remain unclear. OBJECTIVE: Our goals were to determine the incidence, outcome and changes in haemostatic parameters in patients with VOD. Also, we tried to determine coagulation disturbances and their practical significance in early diagnosis of such patients. METHODS: We prospectively evaluated all consecutive VOD patients after SCT, aged 3 months to 17 years, from February 2004 to July 2008 treated at the Mother and Child Health Institute of Serbia "Dr Vukan Cupic" (IMD). All patients were diagnosed according to the Seattle criteria. The values of PT, aPTT, fibrinogen, FVIII, AT and vWF were measured on the day prior to the initiation of conditioning regiment and on the days 1, 7 and 14 from the moment of VOD diagnosis. Laboratory testing was performed in the IMD haemostasis laboratory and results were statistically evaluated. RESULTS: During the study period 74 SCT were performed at IMD. VOD developed 11 patients; 10 of 46 were autologous and 1 of 28 allogeneic SCT patients. In our group of patients the incidence of VOD was 14.8%. VOD was classified as mild in 7, moderate in 1 and severe in 3 patients. At the moment of establishing the diagnosis all patients had a significantly increased activity of vWF, FVIII and fibrinogen, and decreased AT. All of them were dependent on platelet transfusions. CONCLUSION: Platelet transfusion dependence suggests coagulation activation with great significance and indicates a possible development of VOD. Our results also suggest that monitoring coagulation parameters levels in the first five days from the establishment of diagnosis may have a significant predictive value for VOD outcome.

Plasma and cryoprecipitate manufactured from whole blood held overnight at room temperature meet quality standards.

BACKGROUND: With buffy coat (BC) processing of whole blood (WB) donations, the preparation of plasma occurs within 24 hours rather than 8 hours of collection. The effect of this change on coagulation factor function in plasma and cryoprecipitate was evaluated during the validation of this production method and with routine production. STUDY DESIGN AND METHODS: Plasma frozen after an overnight hold of WB was prepared via BC or whole blood filtration (WBF) methods and quality control (QC) variables were measured. Additionally, plasma prepared with the BC method was compared to plasma produced using the platelet-rich plasma (PRP) method with an extended plasma factor analysis. Selected plasma factor levels were also measured in both cryoprecipitate and cryosupernatant plasma prepared using the WBF method from plasma frozen on the day of collection or after an overnight hold of WB. RESULTS: When comparing BC plasma to PRP plasma, coagulation factors (F)II, VII, VIII, IX, X, and XI had somewhat lower levels, and fibrinogen and antithrombin levels were elevated. As expected the most sensitive to the prolongation of production time was FVIII with 72 and 78% of the activity of PRP plasma and cryoprecipitate, respectively. However, both still met QC standards. Similarly, products made in routine production show acceptable levels of FVIII. CONCLUSION: Plasma and cryoprecipitate products, prepared using methods in which the plasma is frozen close to 24 hours after collection, meet current quality standards. The longer WB storage time has been implemented into general use in Canada.

Effect of a miniaturized cardiopulmonary bypass system on the inflammatory response and cardiac function in neonatal piglets.

The cognitive impairment and hemodynamic instability after neonatal cardiac surgery with cardiopulmonary bypass (CPB) might be exacerbated by hemodilution. Therefore, this study investigated the impact of different bloodless prime volumes on the hemodynamics and the inflammatory response by a miniaturized CPB system in neonatal piglets. The bypass circuit consisted of a Capiox RX05 (Capiox Baby RX, Terumo Corp., Tokyo, Japan) oxygenator and 3/16 internal diameter arterial and venous polyvinyl chloride tubing lines, with a minimum 75 mL prime volume. Twelve 1-week-old piglets were placed on a mild hypothermic CPB (32 degrees C) at 120 mL/kg/min for 2 h. The animals were divided into two groups, based on the volume of the prime solution. The priming volume was 75 mL in Group I and 175 mL in Group II. No blood transfusions were performed, and no inotropic or vasoactive drugs were used. The interleukin-6 (IL-6) and thrombin-antithrombin (TAT) complex levels, as well as right ventricular and pulmonary functions, were measured before and after CPB. Group I had low levels of IL-6 and TAT immediately after CPB (4370 +/- 2346 vs. 9058 +/- 2307 pg/mL, P < 0.01 and 9.9 +/- 7.7 vs. 25.1 +/- 8.8 ng/mL, P < 0.01, respectively). Group I had significantly improved cardiopulmonary function, cardiac index (0.22 +/- 0.03 vs. 0.11 +/- 0.05 L/kg/min, P < 0.001), and pulmonary vascular resistance index (7366 +/- 2860 vs. 28 620 +/- 15 552 dynes/cm(5)/kg, P < 0.01) compared with Group II. The miniaturized bloodless prime circuit for neonatal CPB demonstrated that the influence of hemodilution can reduce the subsequent inflammatory response. In addition, a low prime volume could therefore be particularly effective for attenuating pulmonary vascular resistance and right ventricular dysfunction in neonates.

Anti-thrombosis repertoire of blood-feeding horsefly salivary glands.

Blood-feeding arthropods rely heavily on the pharmacological properties of their saliva to get a blood meal and suppress immune reactions of hosts. Little information is available on antihemostatic substances in horsefly salivary glands although their saliva has been thought to contain wide range of physiologically active molecules. In traditional Eastern medicine, horseflies are used as anti-thrombosis material for hundreds of years. By proteomics coupling transcriptome analysis with pharmacological testing, several families of proteins or peptides, which exert mainly on anti-thrombosis functions, were identified and characterized from 60,000 pairs of salivary glands of the horsefly Tabanus yao Macquart (Diptera, Tabanidae). They are: (I) ten fibrin(ogen)olytic enzymes, which hydrolyze specially alpha chain of fibrin(ogen) and are the first family of fibrin(ogen)olytic enzymes purified and characterized from arthropods; (II) another fibrin(ogen)olytic enzyme, which hydrolyzes both alpha and beta chain of fibrin(ogen); (III) ten Arg-Gly-Asp-motif containing proteins acting as platelet aggregation inhibitors; (IV) five thrombin inhibitor peptides; (V) three vasodilator peptides; (VI) one apyrase acting as platelet aggregation inhibitor; (VII) one peroxidase with both platelet aggregation inhibitory and vasodilator activities. The first three families are belonging to antigen five proteins, which show obvious similarity with insect allergens. They are the first members of the antigen 5 family found in salivary glands of blood sucking arthropods to have anti-thromobosis function. The current results imply a possible evolution from allergens of blood-sucking insects to anti-thrombosis agents. The extreme diversity of horsefly anti-thrombosis components also reveals the anti-thrombosis molecular mechanisms of the traditional Eastern medicine insect material.

Haemostatic markers in patients with abdominal aortic aneurysm and the impact of aneurysm size.

INTRODUCTION: Abdominal aortic aneurysm is a common condition with high mortality when rupturing. However, the condition is also associated with nonaneurysmal cardiovascular mortality. A possible contributing mechanism for the thrombosis related cardiovascular mortality is an imbalance between the activation of the coagulation system and the fibrinolytic system. The aim of the present study was to investigate haemostatic markers in patients with nonruptured abdominal aortic aneurysm with special regard to the influence of aneurysm size and smoking habits. METHODS: Seventy-eight patients with infrarenal aortic aneurysm and forty-one controls without aneurysm matched by age, gender and smoking habits were studied. Thrombin-antithrombin (TAT), prothrombin fragment 1+2 (F 1+2)--markers of thrombin generation, and von Willebrand factor antigen (vWFag)--considered as a reliable marker of endothelial dysfunction--were measured. Plasma levels of tissue plasminogen activator antigen (tPAag), and plasminogen activator inhibitor type 1 (PAI-1) were measured as markers of fibrinolytic activity. D-dimer, a marker of fibrin turnover, was also measured. RESULTS: There were significantly higher levels of TAT and D-dimer in patients with abdominal aortic aneurysm. The highest level of TAT and D-dimer were detected in patients with large compared to small AAA. CONCLUSIONS: The present data indicate a state of activated coagulation in patients with abdominal aortic aneurysm which is dependent by aneurysm size. The activated coagulation in AAA patients could contribute to an increased cardiovascular risk in patients also with small AAA. The possible impact of secondary prevention apart from smoking cessation has to be further evaluated and is maybe as important as finding patients at risk of rupture.

Hyperhomocysteinemia, antithrombin consumption, and early venous graft closure in surgical coronary revascularization.

Hyperhomocysteinemia is a pathological condition that increases cardiovascular risk due to prothrombotic behaviour in the patient. This case report concerns a 61-year-old man undergoing surgical coronary revascularization for early thrombosis of the venous graft. The postoperative antithrombin activity was extremely low (33%), despite normal preoperative values (79%) and a short cardiopulmonary bypass. At a subsequent screening, the patient was diagnosed with hyperhomocysteinemia (18.4 mmol/L) due to a heterozygous C677T mutation of the enzyme methylenetetrahydrofolate reductase associated with a folate deficiency. Hyperhomocysteinemia and cardiac operation are both factors that induce increased thrombin formation, which may induce antithrombin consumption and a consequent thrombotic event. Further studies are needed to define hyperhomocysteinemia as an independent risk factor for thrombotic events after cardiac surgery.

Metabolic syndrome in postmenopausal women: the influence of oral or transdermal estradiol on inflammation and coagulation markers.

OBJECTIVE: The objective of the study was to determine whether the route of administration of estrogen therapy in women with metabolic syndrome (MBS) influences inflammation and coagulation parameters. STUDY DESIGN: Fifty symptomatic postmenopausal women with MBS were randomized to receive 1 mg oral estradiol (oE(2)) or 0.05 mg transdermal E(2) (tE(2)) for 3 months. Measurements were compared with those of 20 healthy premenopausal women and 74 normal postmenopausal women. RESULTS: Compared with both control groups, women with MBS had significantly higher levels of certain inflammation and coagulation markers, which cannot be accounted for based on weight alone. After oE(2), antithrombin III decreased from 104% to 96% (P < .01), the metalloproteinase-9/ tissue inhibitor of metalloproteinase-1 ratio increased (P < .02), and E-selectin decreased from 60 +/- 4.4 to 55 +/- 4.6 ng/mL (P < .05). With tE(2), there were no major changes noted. CONCLUSION: Postmenopausal women with MBS have higher levels of certain coagulation and inflammation markers and different responses to oral compared with transdermal estradiol.

A prospective longitudinal multicenter study of coagulation in pediatric patients undergoing allogeneic stem cell transplantation.

BACKGROUND: Thrombotic complications occur in adult patients undergoing stem cell transplantation (SCT), especially following high dose chemo-radiotherapy. There is little published information in children on the impact of SCT on coagulation, as well as potential correlations between altered coagulation and SCT-associated thrombosis and organ failure. PROCEDURE: Forty three pediatric subjects who underwent allogeneic SCT were prospectively evaluated for congenital thrombophilia, anticoagulant levels, coagulation activation, and fibrinolysis at pre-established set points encompassing the period from the 2 to 4 weeks prior to conditioning to 28 days post-transplantation. RESULTS: A significant decrease of protein C and antithrombin levels was found in 39% and 31% of subjects respectively, between SCT days +6 and +7. A peak in plasminogen activator inhibitor-1 levels in 31% of subjects was noted between days +9 and +10. No subject experienced a thrombotic event or other SCT-related organ failure. Antithrombin deficiency correlated with underlying malignancy, donor HLA-mismatch, and TBI, whereas decreased PC activity demonstrated a trend of association with lack of T-cell depletion and TBI. Prophylactic heparin did not influence the pattern of acquired hemostatic abnormalities observed in this cohort. CONCLUSIONS: Children undergoing allogeneic SCT develop a state of acquired thrombophilia in the early post-transplantation period. Although no SCT-related thromboembolic events were observed, our results provide new information about the hemostatic changes in children undergoing allogeneic SCT and their potential clinical triggers. The significance of these findings requires further prospective evaluation in a larger cohort of patients.

[Factors influencing thrombin generation measured as thrombin-antithrombin complexes levels and using calibrated automated thrombogram in patients with advanced coronary artery disease]. / Czynniki wplywajace na generacje trombiny mierzona jako stezenie kompleksów trombina-antytrombina i metoda automatycznego skalibrowanego trombogramu u chorych z zaawansowana choroba wiencowa.

INTRODUCTION: Haemostatic factors play an important role in atherothrombosis. Thrombin generation is a crucial stage of blood coagulation. OBJECTIVES: Comparison of different thrombin generation markers: thrombin-antithrombin complex (TAT) generation and calibrated automated thrombogram method (CAT). Identification of factors influencing thrombin generation in patients with stable angina (SA) enrolled to the coronary artery bypass grafting (CABG) surgery. Analysis of traditional (age, gender, hypertension and diabetes) and novel (fibrinogen and C-reactive protein [CRP]) risk factors and the antiplatelet therapy (aspirin 75-150 mg/d) in relation to coagulation. PATIENTS AND METHODS: In 135 SA patients with left main coronary artery stenosis (> 50%) or major epicardial artery stenosis (> 70%), plasma TAT levels, maximal thrombin concentration (C(max)) and endogenous thrombin potential (ETP) were determined. A marker of the platelet activation (beta-thromboglobulin) was also measured. RESULTS: No correlations among TAT, C(max), ETP, risk factors and beta-thromboglobulin were observed. Linear regression model showed that independent predictors of TAT levels were age (beta = 0.5; p = < 0.0001), male gender and diabetes (beta = 0.36; p = 0.02). CRP independently predicted TAT and ETP (beta = -0.24 and beta = 0.22; p < 0.05, respectively), while fibrinogen predicted C(max) (beta = 0.21; p < 0.05). Independent predictors of beta-thromboglobulin were a male gender and aspirin use cessation (beta = 0.46; p = 0.01). Aspirin treatment had no effect on thrombin generation. CONCLUSIONS: Age, higher fibrinogen, CRP, diabetes and male gender influence thrombin generation and/or coagulation activation in SA patients. Plasma levels of thrombin-antithrombin complexes do not correlate with the parameters obtained using the calibrated automated thrombogram method (C(max), ETP).

Effect of estrogen-progestin hormonal replacement therapy on blood coagulation and fibrinolysis in postmenopausal women.

OBJECTIVE: To evaluate antithrombin III (AT), thrombin (Fragment 1+2 [F1+2] and thrombin-antithrombin [TAT]) generation markers, as well as other coagulation parameters, such as prothrombin time, partial activated thromboplastin time, thrombin time, fibrinogen, euglobulin lysis time, and platelet count, in postmenopausal women after hormonal therapy. STUDY DESIGN: Forty-five patients who received either 0.625 mg/day unopposed oral conjugated equine estrogen (CEE), 0.625 mg/day oral CEE plus medroxyprogesterone acetate (MP), or 50 microg/day transdermal 17beta-estradiol plus MP, were included. Tests were performed before (T0) and after 3 (T3), 6 (T6) and 12 (T12) months of treatment. AT was determined by an amidolytic method, whereas F1+2 and TAT complex were measured by ELISA. RESULTS: There was a significant reduction in the AT level of patients who received oral CEE plus MP at T3. There was no AT reduction in patients taking either oral CEE alone or transdermal 17beta-estradiol plus MP. F1+2 increased in all patients, but it reached statistical significance only in patients receiving transdermal 17beta-estradiol MP at T3. CONCLUSIONS: The CEE associated with MP treatment may reduce AT levels, whereas unopposed CEE or transdermal 17beta-estradiol plus MP does not change AT. These changes might not be clinically relevant in the general population; however, hormonal replacement therapy may increase the risk of thrombosis in women with congenital or acquired thrombophilia.

Activated coagulation factors in human malignant effusions and their contribution to cancer cell metastasis and therapy.

We have shown that the thrombin G-protein coupled receptors (GPCR) designated as protease-activated receptors (PAR-1) are expressed in primary cancer cells isolated from peritoneal and pleural malignant effusions. Here, our main goal was to evaluate several coagulation and thrombin activation effectors and markers in a series of 136 malignant effusions from cancer patients with gastrointestinal, lung and mammary carcinomas. All these patients present a highly activated coagulation system in blood and their malignant effusions, as indicated by high levels of prothrombin F1.2 fragments and D-dimers. Notably, we detected in the effusions all the coagulation factors of the tissue factor pathway inducing thrombin activation, namely factors VII, V, X and II, as well as high VEGF levels and IGF-II in mature and precursor forms. Fibrin clot formation also correlated with higher levels of free ionized calcium (iCa), suggesting that iCa and its binding protein albumin are regulatory factors for fibrinogenesis in effusions. Consequently, thrombin, VEGF and IGFII appear to converge in the promotion of survival and invasivity of the metastatic cancer cells from blood to the malignant effusions. Thus, we add new insights on the interconnections between blood coagulation disorders in cancer patients and thrombin activation in malignant effusions, including their functional interaction with PAR in metastatic cancer cells. Based on these data we propose to counteract the metastatic cascades by targeted invalidation of key effectors of the coagulation system. Therefore, potential therapeutic approaches include the application of thrombin protease inhibitors, VEGF-blocking antibodies, and drugs targeting the VEGF and thrombin signaling pathways, such as tyrosine kinase or GPCR inhibitors.