Concentrations Of Tissue Plasminogen Activator Research Articles

Congruent identification of imbalanced fibrinolysis by 2 distinct clot lysis time assays

BackgroundA plasma-based clot lysis time (CLT) assay is an established research test to assess plasma fibrinolytic potential, with application in hyperfibrinolytic or hypofibrinolytic conditions. Interprotocol variations make comparisons between laboratories challenging. The aim of this study was to compare the results of 2 different CLT assays performed by 2 distinct research laboratories by using their own protocol. MethodsWe evaluated fibrinolysis in the plasma of 60 patients undergoing hepatobiliary surgery and in plasma from a healthy donor that was spiked with commonly used anticoagulant drugs (enoxaparin, dabigatran, and rivaroxaban) in 2 distinct laboratories (Aarhus and Groningen) by using 2 different assays that differ, among others, in tissue plasminogen activator (tPA) concentration. ResultsOverall conclusions on fibrinolytic potential in patients undergoing hepatobiliary surgery were similar between the 2 CLT assays, with hyperfibrinolytic and hypofibrinolytic profiles identified at the same time points during and after surgery. Severe hypofibrinolysis was less commonly reported in the Aarhus assay (36/319 samples; 11%) than in the Groningen assay (55/319 samples; 17%). No clot formation was observed in 31 of 319 samples in the Aarhus assay vs 0 of 319 samples in the Groningen assay. Clotting times increased much more profoundly on the addition of all 3 anticoagulants in the Aarhus assay. ConclusionsDespite the differences in laboratory, protocol, reagents, operator, data processing, and analysis, overall conclusions on fibrinolytic capacity are similar between the 2 laboratories. With a higher concentration of tPA in the Aarhus assay, the test becomes less sensitive for the detection of hypofibrinolysis and is more sensitive to the addition of anticoagulants.

Connexin43 in Post-Surgical Peritoneal Adhesion Formation.

Post-surgical peritoneal adhesions are a serious problem for the quality of life and fertility. Yet there are no effective ways of preventing their occurrence. The gap junction protein Cx43 is known to be involved in fibrosis in several different organs and disease conditions often associated with inflammation. Here we examined the Cx43 dynamic expression in an ischemic button model of surgical adhesions. Using the mouse ischemic button model, Cx43 antisense was delivered in Pluronic gel to attenuate Cx43 expression. The severity of button formation and immunofluorescence analysis of Cx43 and TGF-β1 were performed. The concentration of tissue plasminogen activator via ELISA was also performed. As early as 6 h after button formation, the Cx43 levels were elevated in and around the button and some weak adhesions were formed. By 24 h Cx43 levels had increased further and adhesions were more defined. At 7 days the adhesions were much more robust, opaque, and vascularized, requiring blunt or sharp dissection to break them. Cx43 antisense attenuated its upregulation and, reduced the number and severity of adhesions that formed. Targeting Cx43 after surgical procedures may be a potential therapeutic strategy for preventing adhesion formation or at least reducing their severity.

Comparative Study on the Chronic Vascular Responses Induced by Regular Versus Occasional Waterpipe Smoke Inhalation in Mice.

Waterpipe smoke (WPS) is the second most prevalent form of smoking in the world. There are ample evidences about the vascular alterations caused by regular WPS (Reg-WPS). Nonetheless, comparison of the chronic vascular response induced by regular versus occasional WPS (Occ-WPS) exposure is very scarce. We investigated, in BALB/c mice, the effects of Occ-WPS (30 minutes/day, 1 day/week) versus Reg-WPS (30 minutes/day, 5 days/week) for 6 months on thrombogenicity and platelet aggregation in vivo and in vitro. Moreover, various markers of endothelial integrity, inflammation and oxidative stress were assessed by enzyme-linked immunosorbent assay and colorimetric assay. Control mice were exposed to air. Our results showed that either Occ-WPS or Reg-WPS exposure shortened the thrombotic time in pial microvessels in vivo. Moreover, in pial venules, this effect was more marked in Reg-WPS group (-47%) compared with Occ-WPS (-34%). Similarly, exposure to either Occ-WPS or Reg-WPS reduced the prothrombin time and activated partial thromboplastin time. Platelet count was increased only in Reg-WPS exposure. Exposure to either Occ-WPS or Reg-WPS induced platelet aggregation in vitro. In addition, there was a statistically significant difference between Occ-WPS and Reg-WPS groups in platelet count and aggregation. Plasma concentration of tissue factor (+98%), P-selectin (+14%) and E-selectin (+16%) were significantly increased in Occ-WPS group compared with air exposed group. Likewise, compared with air group Reg-WPS caused an increase in concentration of tissue factor (+193%), P-selectin (+21%) and E-selectin (+42%). Nevertheless, only Reg-WPS induced a decrease (-38%) in the plasma concentration of tissue plasminogen activator. Notably, our results showed a statistically significant difference between Occ-WPS and Reg-WPS groups in the concentration of tissue factor. Erythrocyte numbers, hemoglobin concentration, hematocrit and lactate dehydrogenase activity were augmented only in Reg-WPS group compared with either control or Occ-WPS groups. Likewise, only Reg-WPS induced an increase in proinflammatory cytokines, tumor necrosis factor-α and interleukin-1β compared with either control or Occ-WPS groups. However, markers of oxidative stress including 8-isoprostane and total antioxidants were enhanced in both Occ-WPS and Reg-WPS compared with control group. Our data confirm the vascular toxicity of the chronic Reg-WPS exposure and shows that even occasional chronic exposure to WPS caused thrombosis, platelet aggregation, endothelial alterations and oxidative stress. The latter findings are an additional cause of concern about the long-term toxicity of occasional waterpipe smoking.

Гострий тромбоз стента при інфаркті міокарда, ускладненому кардіогенним шоком, за наявності цукрового діабету 2-го типу

Актуальність. Гострий тромбоз стента (ТС) є нечастим, але грізним ускладненням при стентуванні вінцевих артерій. Він виникає під час черезшкірних коронарних втручань або впродовж 24 годин після цієї процедури. Мета дослідження: з’ясувати причини та проаналізувати фактори, що призвели до гострого ТС при гострому коронарному синдромі і цукровому діабеті (ЦД) 2-го типу, для уникнення подібних ускладнень. Матеріали та методи. Обстежено 119 пацієнтів із гострим інфарктом міокарда з елевацією сегмента ST, які лікувалися в інфарктному відділенні комунального некомерційного підприємства «Клінічна лікарня швидкої медичної допомоги м. Львова». Усім пацієнтам проводили коронарографію та стентування вінцевих артерій, ультраструктурні дослідження тромбоцитів венозної крові за допомогою електронної мікроскопії. Результати. Пацієнти із ЦД 2-го типу мають вищий кардіоваскулярний ризик розвитку серцево-судинних ускладнень, що пов’язано з ендотеліальною дисфункцією, схильністю до гіперкоагуляції і, як наслідок, тенденцією до вазоконстрикції, запальних реакцій та порушень гемостазу. У цієї категорії пацієнтів спостерігається підвищена адгезивність тромбоцитів і збільшена концентрація тканинного активатора плазміногену. В експрес-некроптатах і періопераційних біоптатах міокарда пацієнтів із ЦД нами виявлено домінування процесів гіперкоагуляції в мікросудинах міокарда в результаті активності системи згортання крові за відсутності безпосередньої участі тромбоцитів, оскільки частина з них була кальцифікована (осміофільні) і мала знижену функціональну здатність, в результаті чого відмічається резистентність до аспірину. В осіб із ЦД 2-го типу виникає зазвичай тяжкий і більш генералізований коронаросклероз, що призводить до погіршення перебігу гострого коронарного синдрому і частішого виникнення ТС, що робить доцільним додаткове призначення ривароксабану цій категорії пацієнтів. Висновки. Враховуючи виявлені нами ознаки зниженої реактивності тромбоцитів і домінування активації системи згортання крові у хворих на ЦД і з підвищеним ризиком коронаротромбозу, вважаємо, що застосування нових пероральних антикоагулянтів є актуальним і заслуговує подальших досліджень.

Local Cerebral Recombinant Tissue Plasminogen Activator Concentrations During Acute Stroke

Local Cerebral Recombinant Tissue Plasminogen Activator Concentrations During Acute Stroke

Some fibrinolytic parameters in coronary artery disease patients: focus on unstable angina subgroups

Unstable angina is classified into new-onset, progressive, and angina at rest. Though hemostasis plays a crucial role in the pathogenesis of coronary artery disease, including unstable angina, limited data exist regarding peculiarities of fibrinolytic parameters in the above-mentioned types of unstable angina. Our study aims to investigate if there is a difference in the fibrinolytic state between the groups of patients with new-onset, progressive unstable angina in comparison with stable angina patients depending on medical history data, electrocardiographic and hemodynamic features. In our cross-sectional study, we recruited 93 coronary artery disease patients (mean age 62.32 (6.94) years, 41 males (44.1%)). They were divided into 3 groups: stable angina patients (n=22) (control), new-onset unstable angina patients (n=21), and progressive unstable angina patients (n=50). The groups were comparable by baseline characteristics. Blood samples were obtained before treatment onset. The concentrations of tissue plasminogen activator and inhibitor of plasminogen activator (type 1) were measured by the ELISA method. We registered 14 points at the admission department, particularly age, sex, body mass index, smoking, presence of the family history of cardiovascular disorders, ST-segment depression, T-wave variability, arrhythmias, left bundle branch blockage, heart rate, systolic and diastolic blood pressure, Sokolov-Lyon voltage criteria, and unstable angina type (new-onset or progressive). After comparison of fibrinolytic parameters’ concentrations among groups under investigation, we defined the main independent predictors among observed 14 parameters to create optimal regression models for assessment of fibrinolytic parameters concentrations. The groups under investigation differ significantly in concentration of tissue plasminogen activator (P<0.001) and inhibitor of plasminogen activator (type 1) (P<0.001). The tissue plasminogen activator concentration correlated significantly with ST depression (r=0.344, P=0.001), T wave variability (r=-0.233, P=0.02), systolic blood pressure (r=-0.675, P<0.001), diastolic blood pressure (r=-0.655, P<0.001), heart rate (r=-0.568, P<0.001) and clinical unstable angina subgroups (r=-0.706, P<0.001) as well as plasminogen activator inhibitor (type 1) concentration associated with age (r=-0.560, P<0.001), body mass index (r=-0.249, P=0.049), ST-segment depression (r=0.542, P<0.001), arrhythmia (r=0.210, P=0.03), systolic blood pressure (r=0.310, P=0.04), and clinical unstable angina subgroups (r=-0.406, P<0.001). An optimal regression models for tissue plasminogen activator and its inhibitor assessment included systolic blood pressure, heart rate, unstable angina subgroup (R2adj. = 65.0%, P<0.001) and systolic blood pressure, unstable angina subgroup (R2adj. = 42.7%, P<0.001), respectively. Thus, fibrinolytic state among unstable angina clinical types differs significantly independently on observed baseline clinical, electrocardiographic and hemodynamic parameters. This finding confirms the utility of Braunwald unstable angina classification.

Aberrant Factors of Fibrinolysis and Coagulation in Pancreatic Cancer.

Aberrant factors associated with fibrinolysis and thrombosis are found in many cancer patients, which can promote metastasis and are associated with poor prognosis. The relationship between tumor-associated fibrinolysis and thrombosis is poorly understood in pancreatic cancer. This review provides a brief highlight of existing studies that the fibrinolysis and coagulation systems were activated in pancreatic cancer patients, along with aberrant high concentrations of tissue plasminogen activator (t-PA), urine plasminogen activator (u-PA), D-dimer, fibrinogen, or platelets. These factors cooperate with each other, propelling tumor cell shedding, localization, adhesion to distant metastasis. The relationship between thrombosis or fibrinolysis and cancer immune escape is also investigated. In addition, the potential prevention and therapy strategies of pancreatic cancer targeting factors in fibrinolysis and coagulation systems are also been discussed, in which we highlight two effective agents aspirin and low-molecular weight heparin (LMWH). Summarily, this review provides new directions for the research and treatment of pancreatic cancer.

Cannabidiol Ameliorates Monocrotaline-Induced Pulmonary Hypertension in Rats.

Cannabidiol (CBD) is known for its vasorelaxant (including in the human pulmonary artery), anti-proliferative and anti-inflammatory properties. The aim of our study was to examine the potential preventive effect of chronic CBD administration (10 mg/kg/day for three weeks) on monocrotaline (MCT)-induced pulmonary hypertension (PH) rats. PH was connected with elevation of right ventricular systolic pressure; right ventricle hypertrophy; lung edema; pulmonary artery remodeling; enhancement of the vasoconstrictor and decreasing vasodilatory responses; increases in plasma concentrations of tissue plasminogen activator, plasminogen activator inhibitor type 1 and leukocyte count; and a decrease in blood oxygen saturation. CBD improved all abovementioned changes induced by PH except right ventricle hypertrophy and lung edema. In addition, CBD increased lung levels of some endocannabinoids (anandamide, N-arachidonoyl glycine, linolenoyl ethanolamide, palmitoleoyl ethanolamide and eicosapentaenoyl ethanolamide but not 2-arachidonoylglycerol). CBD did not affect the cardiopulmonary system of control rats or other parameters of blood morphology in PH. Our data suggest that CBD ameliorates MCT-induced PH in rats by improving endothelial efficiency and function, normalization of hemostatic alterations and reduction of enhanced leukocyte count determined in PH. In conclusion, CBD may be a safe, promising therapeutic or adjuvant therapy agent for the treatment of human pulmonary artery hypertension.

The use of thromboelastography to assess post-operative changes in coagulation and predict graft function in renal transplantation

BackgroundEnd stage renal disease (ESRD) is associated with elevated fibrinogen levels and fibrinolysis inhibition. However, there is a paucity of data on how renal transplantation impacts coagulation. we hypothesize that renal transplantation recipients with good functioning grafts will have improved fibrinolytic activity following surgery. MethodsKidney recipients were analyzed pre-operatively and on post-operative day 1(POD1) using three different TEG assays with and without two concentration of tissue-plasminogen activator (t-PA). TEG indices and percent reduction in creatinine from pre-op to POD1 were measured, with >50% defining “good” graft function. Follow up was done at 6, 12, and 24 months. ResultsPercent lysis(LY30) on POD1 the t-PA TEG was significantly correlated to change creatinine from pre-op to POD-1(p = 0.006). A LY30 ≥ 23% was associated with good early graft function, and lower creatinine at 24-months(p = 0.028) compared to recipients with low POD1 LY30. ConclusionsPost-operative tPA-TEG LY30 is associated with favorable early and late outcomes in kidney transplant.

Increased Circulating Levels of Tissue-Type Plasminogen Activator Are Associated with the Risk of Spontaneous Abortion During the First Trimester of Pregnancy.

Spontaneous abortion is a common complication in early pregnancy, with an incidence of around 20%. Ultrasound scan and measurement of human chorionic gonadotropin are used to identify patients at risk of spontaneous abortion; however, there is a clinical need to find new biomarkers to prospectively identify patients before the onset of clinical symptoms. Here, we aim to investigate potential biomarkers of spontaneous abortion taken in the first clinical appointment of pregnancy. A case–control study was conducted based on a prospectively collected cohort in which cases and controls were retrospectively stratified based on pregnancy outcome: normal healthy pregnancies (controls = 33) and pregnancies that ended in spontaneous abortion (cases = 10). We evaluated extracellular vesicles isolated by precipitation with ExoQuick™ and protein concentrations of tissue plasminogen activator, leptin, and adiponectin measured by ELISA. The extracellular vesicles showed the typical morphology and membrane proteins: CD63, Alix, and Flotilin-1. The size distributions of the isolated extracellular vesicles were 112 ± 27 and 118 ± 28 nm in diameter for controls and spontaneous abortion, respectively, and the total amount of extracellular vesicles did not show any difference between controls and the spontaneous abortion group. The tissue plasminogen activator showed a significant difference (p = 0.0004) between both groups, although neither adiponectin nor leptin revealed significant changes, indicating that women who had spontaneous abortions have significantly higher levels of tissue plasminogen activator than women who had normal pregnancies.

Implications of Hemostasis Disorders in Patients with Critical Limb Ischemia-An In-Depth Comparison of Selected Factors.

Background: Atherosclerosis is a systemic disease. Among patients with atherosclerosis, those suffering from peripheral arterial disease (PAD) represent a group of individuals with particularly high death risk, especially during the course of critical limb ischemia (CLI). In the pathogenesis of PAD/CLI complications, blood coagulation disorders play a significant role. The study aim was to examine the activation of the coagulation system depending on tissue factor (TF) in patients with CLI as compared with those with intermittent claudication (IC). Methods: Before initiating proper treatment (invasive or maintenance), blood samples were collected from 65 patients with CLI and 15 with IC to measure the following selected hemostasis parameters: concentrations and activation of tissue factor (TF Ag and TF Act) and tissue factor pathway inhibitor (TFPI Ag and TFPI Act), concentrations of thrombin–antithrombin complex (TAT Ag) and fibrinogen, platelet count (PLT), and concentrations of tissue-plasminogen activator (t-PA Ag), plasminogen activator inhibitor 1 (PAI-1), and D-dimer. The control group included 30 healthy volunteers (10 female/20 male). Results: The values of all analyzed parameters (except for lower TFPI Act) were significantly higher in the blood of PAD patients (with respect to PLT only in the CLI subgroup) in comparison with healthy subjects. The blood of patients with CLI as compared to the IC subgroup revealed much higher concentrations of TF Ag (p < 0.001), with slightly decreased TF Act, significantly lower concentrations of TFPI Ag (p < 0.001), slightly increased TFPI Act, and significantly higher levels of TAT Ag (p < 0.001), fibrinogen (p = 0.026), and D-dimer (p < 0.05). Conclusions: In patients with CLI, we can observe coagulation activation and a shifting balance toward prothrombotic processes. Furthermore, increased concentrations of D-dimer suggest a secondary activation of fibrinolysis and confirm the phenomenon as a prothrombotic condition with heightened fibrinolysis.

Evaluation of the prognostic value of fibrinolytic elements in invasive breast carcinoma patients.

Breast cancer (BrC) is one of the most serious oncological problems in the world. The aim of the study was to evaluate concentrations of tissue plasminogen activator (t-PA) and plasminogen activator inhibitor type 1 (PAI-1) and their ratios: t-PA/PAI-1 and PAI-1/t-PA in breast cancer patients and in healthy individuals and to estimate the ability of fibrinolytic parameters in predicting neoplasm disease and disease relapse. One hundred and five women were enrolled in the study, including 60 cases with primary BrC, (M0) and 45 healthy females. Follow-up was completed in all BrC patients with a 16.7% recurrence rate. An immunoassay of t-PA, PAI-1 in all cases was made as well as the immunohistochemistry of estrogen and progesterone receptors, human epidermal growth factor receptor 2, E-cadherin, and Ki-67 was performed in BrC subjects. A significantly higher PAI-1 concentration in breast cancer patients below the age of 55 than in controls was obtained. According to the ROC curve analysis, the PAI-1 concentration demonstrates the most accurate prognostic value with the cut-off point at 33.91 ng/ml, with 90% sensitivity and 36% specificity, which discriminates between controls and cancer patients. However, t-PA presents the highest area under the receiver-operating characteristic curves (AUCROC)=0.634 in predicting disease relapse with the cut-off value of 5.3 ng/ml. According to the Kaplan-Meier curves, a high concentration of t-PA (>5 ng/ml) and a lower PAI-1/t-PA ratio (<7.5) are associated with shorter survival. Evaluation of plasma t-PA and PAI-1 concentrations may deliver relevant prognostic information for breast cancer patients.

Fibrinolytic System Changes in Liver Surgery: A Pilot Observational Study.

Introduction: Bleeding occurs frequently in liver surgery. Unbalance between tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) concentrations might increase bleeding. Our aim was to analyze perioperative fibrinolytic changes during liver surgery.Materials and Methods: We evaluated 15 patients for inclusion into a prospective pilot study of liver surgery. We assessed fibrinolysis by plasma PAI-1 and t-PA: before surgery (T1), before Pringle maneuver (PM;T2), at the end of surgery (T3) and 24 h postoperatively (T4), and registered demographic and laboratory data, extent and duration of surgery, hemodynamic parameters, blood loss, and transfused volumes of blood products. Data presented as mean ± SD. Significance at P < 0.05.Results: After exclusion of six patients only undergoing biopsies, we included six women and three men aged 49.1 ± 19.6 years; two patients with liver metastases of colorectal cancer and hepatocellular carcinoma, respectively, two with focal nodular hyperplasia, two with hepatic hemangioma, and one with angiomyolipoma. Six patients underwent PM. PAI-1 plasma concentration (n = 9) rose from 6.25 ± 2.25 at T1 through 17.30 ± 14.59 ng/ml at T2 and 28.74 ± 20.4 (p = 0.007) and 22.5 ± 16.0 ng/ml (p = 0.04), respectively, at T3 and T4. Correspondingly, t-PA plasma concentration (n = 9) increased from 4.76 ± 3.08 ng/ml at T1 through 8.00 ± 5.10 ng/ml (p = 0.012) at T2 and decreased to 4.25 ± 2.29 ng/ml and 3.04 ± 3.09 at T3 and T4, respectively. Plasma t-PA level at T2 was significantly different from those at T1, T3, and T4 (p < 0.004). In PM patients, t-PA levels increased from T1, peaked at T2 (p = 0.001), and subsequently decreased at T3 and T4 (p = 0.011 and p = 0.037), respectively. Mean blood loss was 1,377.7 ± 1,062.8 ml; seven patients received blood products. Patients with higher PAI-1 levels at T3 received more fresh frozen plasma (r = 0.79; p = 0.01) and red blood cells (r = 0.88; p = 0.002).Conclusions: During liver surgery, fibrinolysis increased, as evidenced by rises in plasma PAI-1and t-PA, especially after start of surgery and following PM. Transfused volumes of blood products correlated with higher plasma concentrations of PAI-1. Confirming this tendency requires a larger cohort of patients.

Glucagon-like peptide-1 receptor agonist diminishes endothelial dysfunction in type 2 diabetic patients

Objective. To evaluate liraglutide (LIR) endothelial protective action. Material and methods. Type 2 diabetic patients with HbA1C 7.5-9.0 % had metformin (MET) dose titrated for 3 months. Patients with HbA1C less than 7.5 % comprised group 1 (MET), more than 7.5 % - group 2 (MET+LIR). Blood concentrations of tissue plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1), endothelin-1 (E) were evaluated at baseline, in 3, 6 and 9 months. Results. PAI-1 was increased in both groups and gradually decreased. T-PA was normal. E was primarily increased only in group 2. E was normal in group 1 in general, but enlarged with glycaemia increase. E decreased in group 2 with glycaemia improvement and worsening. Conclusions. Glycaemia control improvement decreases endothelial dysfunction. LIR improves vasomotor endothelial function, independently on its influence on glycaemia.

Antifertility effectiveness of a novel copper-containing intrauterine device material and its influence on the endometrial environment in rats

This study was designed to investigate the antifertility effectiveness of a novel copper-containing intrauterine device material containing a composite of micro-copper (Cu), low-density polyethylene (LDPE), and methyl vinyl silicone rubber (MVQ) and its effects on the endometrial environment in rats. The contraceptive effectiveness was examined 12 days after pregnancy. The pathological changes; factors associated with bleeding, pain, and inflammation in the endometrium; and the surface condition of the implants were investigated after insertion for 90 days. Furthermore, the release rate of copper ions in simulated uterine solution (SUS) was investigated for 270 days. The contraceptive effectiveness was 100% in both the bulk Cu and micro-Cu/LDPE/MVQ groups, and that in the LDPE/MVQ group was 30%. On day 90 after insertion, histopathological observation and the ultrastructural changes in the endometrium showed that the damage caused by bulk Cu was much more severe than that caused by the Cu/LDPE/MVQ microcomposite and that the surface of the latter was much smoother than that of the former. Furthermore, compared with the sham-operated control group, the concentrations of tissue plasminogen activator and prostaglandin E2 were significantly increased 90 days after insertion in all of the experimental groups except for the LDPE/MVQ group (P < 0.05), and the parameters in the Cu/LDPE/MVQ group were significantly lower than those in the Cu group (P < 0.05). In addition, the expression levels of matrix metalloproteinase 9, metalloproteinase 1 tissue inhibitor, plasminogen inhibitor 1, CD34, vascular endothelial growth factor, substance P, and substance P receptor in the endometrium in all of the experimental groups were significantly lower than those in the Cu group 90 days after insertion (P < 0.05). The results of this study indicate that micro-Cu/LDPE/MVQ exhibits satisfactory contraceptive efficacy and causes fewer side effects than Cu.

Comprehensive analysis of haemostatic profile depending on clinicopathological determinants in breast cancer patients.

Thrombosis is one of the leading causes of mortality in cancer patients. The aim of the study was to evaluate the concentrations and activities of selected haemostatic parameters in the plasma of patients diagnosed with breast cancer (BrCa) and to make an attempt at finding associations with their levels and selected clinicopathological factors; clinical classification, histological grading, and molecular subtype of BrCa. The study involved 145 Caucasian ethnicity women. Eighty-five women aged 45–66 with primary BrCa without distant metastases (M0). Inclusion criteria were as follows: histopathological examination confirming the diagnosis of primary BrCa, without previous radiotherapy and chemotherapy. The control group consisted of 60, post-menopausal women, aged 45–68. Haemostatic profile expressed by concentrations and activities of tissue factor (TF) and its inhibitor (TFPI) as well as concentrations of tissue plasminogen activator (t-PA) and plasminogen activator inhibitor type 1 (PAI-1) were measured applying immunoassay techniques. A significantly higher concentration of PAI-1 was noted in patients with BrCa localized in the left breast. We observed significantly lower activity of TFPI and significantly higher concentration of PAI-1 in the group of patients with invasive ductal carcinoma as compared with invasive lobular carcinoma. A significantly higher concentration of t-PA in patients with pT2 BrCa in relation to pT1 cases was noted. Based on comprehensive analysis of haemostatic profile depending on clinicopathological features, we suggest that haemostatic parameters play crucial roles in invasion and metastases of malignant tumours.

High-Intensity Interval Training Does Not Promote Fibrinolytic Adaptations in Healthy Men

Blood clots cause the majority of adverse cardiovascular events, such as heart attack and stroke, and fibrinolysis, the capacity to dissolve blood clots, is recognized as an independent predictor of cardiovascular morbidity and mortality. Aerobic exercise training is theorized to enhance fibrinolytic potential, but studies have yielded inconclusive results. High intensity interval training (HIIT) is a novel exercise training strategy that has been shown to improve several components of health in various populations, but the effect of a HIIT regimen on fibrinolytic potential is unknown. PURPOSE: The purpose of this study was to examine potential fibrinolytic adaptations in healthy men following four and eight weeks of HIIT. METHODS: Healthy, sedentary men participated in a HIIT program three days/week for eight weeks. Training bouts were modeled after the traditional Wingate test, consisting of repeated, 30-second bouts of maximal intensity cycling separated by 4.5 minute rest intervals. Training began with three bouts per day and an additional bout/day was added to the regimen every two weeks, progressing up to six bouts per day in the final two weeks. Plasma concentrations of total tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1) were assessed at baseline, after four weeks (4w), and after eight weeks (8w). Statistical comparisons across the three time points were done using repeated measures ANOVA. Significance was set to p<0.05. RESULTS: 21 men (age: 25± 5 yrs, BMI: 26.7± 6.2 kg/m2) completed the study. No significant changes were observed for tPA during training (baseline: 9.8 ± 3.1, 4w: 9.7 ± 2.9, 8w: 8.9 ± 2.7 ng/ml, p>0.05). Likewise, PAI-1 did not change with training (baseline: 17.7 ± 16.8, 4w: 18.8 ± 16.1, 8w: 18.0 ± 16.8 ng/ml, p>0.05). CONCLUSION: Though it has been suggested that HIIT may be superior to traditional, aerobic training for the purpose of enhancing one’s cardiovascular health, results of the present study do not indicate HIIT influences fibrinolytic potential in healthy young men. Future research should explore the benefits of HIIT in populations that may be characterized by diminished fibrinolytic potential.

Lytic efficacy of tissue plasminogen activator and ultrasound in porcine clots doped with barium sulfate in vitro

Swine and porcine tissue are employed routinely for preclinical models of ischemic stroke. In this study, we examined the lytic susceptibility of porcine whole-blood clots, prepared with and without barium sulfate, a radiopaque x-ray contrast agent. The degree of lytic efficacy in the two types of clots was compared for recombinant tissue plasminogen activator (rt-PA) concentrations ranging from 0 to 100 μg/mL. Subsequently, a in vitro flow model and time-lapse thrombolysis microscopy system was used to evaluate lysis in clots with and without barium sulfate in response to rt-PA and 120-kHz intermittent ultrasound exposure. The degree of lysis observed with both types of clots was similar for rt-PA concentrations up to 15.75 μg/mL. However, clots doped with barium sulfate demonstrated significantly lower lysis at higher rt-PA concentrations. Similarly, results obtained using the in vitro flow model showed that both types of clots underwent comparable lysis when treated with 15.75 μg/mL rt-PA. Further, using Definity® and 120-kHz ultrasound as an adjuvant to rt-PA did not enhance lysis in either porcine clot model compared to rt-PA alone. These results highlight the considerable differences in the degree of clot lysis between porcine clots and previously reported studies that used human clots.

Hemostatic alterations during coronary artery bypass grafting

IntroductionThe origination of blood loss after cardiac surgery is not fully explained, but is related to operation trauma and use of cardiopulmonary bypass (CPB). However, the extent of their contribution is incompletely known and might differ between distinct operation procedures. Materials and methodsThree groups of CABG procedures were studied: 1) off-pump coronary artery bypass surgery (OPCAB, n=11) without CPB, 2) CABG with use of CPB (CABG, n=11) and 3) CABG with use of CPB combined with aortic valve replacement (AVR, n=11). Activation of coagulation and fibrinolysis was measured at various time points by flow cytometry, platelet aggregometry, thrombelastography, the Nijmegen Hemostasis Assay, prothrombin fragment 1+2 and tissue plasminogen activator. Results and conclusionsThe use of CPB during cardiac surgery decreased platelet counts, clot strength, fibrinogen, hematocrit and albumin concentrations during the procedure. No perioperative platelet activation was observed and functional (collagen induced) platelet aggregation was transiently impaired, but recovered after surgery in all groups. Patients operated with use of CPB showed increased tissue plasminogen activator concentrations after reperfusion followed by minor and transient fibrinolysis. After all types of surgery coagulation parameters and platelet aggregation showed a rebound above preoperative levels. To conclude, no evident platelet activation, dysfunction or consumption was demonstrated. In patients using tranexamic acid the most prominent factor impairing hemostasis after CABG surgery was hemodilution associated with CPB.

Interconnectedness of global hemostasis assay parameters in simultaneously evaluated thrombin generation, fibrin generation and clot lysis in normal plasma

BackgroundFluorogenic thrombin generation (TG) assays and turbidity-based fibrin generation (FG)- and fibrinolysis (FL)-resistance assays have been sought to assess bleeding and clotting disorders. Theoretically, TG, FG and FL tests should provide overlapping information because thrombin is responsible for FG and induces protection from FL. The relationships between TG, FG and FL parameters remain poorly investigated, partly because existing experimental systems do not permit simultaneous detection of both TG and FG in the same sample of plasma, and are instead tested in separate experiments. Objectives and methodsWe evaluated the potential benefits of a combined TG/FG/FL assay by testing responses of normal plasma to a wide range of tissue factor (TF) and tissue plasminogen activator (tPA) concentrations. Correlations between multiple parameters extracted from the TG and FG/FL curves were also compared. ResultsRate of FG correlated well with TG peak height at all TF concentrations, but correlations between TG and FL parameters depended on the TF concentration. Without thrombomodulin, all FG/FL parameters at high TF could be predicted from TG parameters and no FL protection was observed. With thrombomodulin and high TF, TF-dependent FL protection did not correlate with TF-dependent TG. The fluorogenic thrombin substrate did not interfere with optical density readings, and meaningful tPA concentrations did not interfere with TG readings. ConclusionsIn normal plasma, TG, FG and FL parameters may provide interchangeable information. Evaluation of FL-resistance may provide additional data under special assay conditions, but the value of this information should be studied under disease conditions.