Increased number of endothelial progenitor cells in the blood of patients with psoriasis vulgaris.

Introduction: Psoriasis vulgaris (PsV) is a common dermatosis characterized by excessive activation of neovascularization. Latest research has shown that endothelial progenitor cells (EPCs) are a crucial factor involved in the repair of endothelial injury and formation of new blood vessels, in a process termed postnatal vasculogenesis. However, the exact mechanism of creating psoriatic skin patches and the involvement of EPCs in this process remains unknown. Aim: To evaluate the number of EPCs in the blood of patients with PsV, characterized by the expression of specific cell surface markers, including CD45-, CD31+, CD34+ and CD133+. Material and methods: A total of 49 patients suffering from PsV and 40 healthy volunteers were enrolled in the study. The number of EPCs in each of the volunteers' whole blood samples was measured with a FACSCalibur flow cytometer using monoclonal antibodies directed against antigens specific for EPCs. Results: The number of EPCs was significantly higher in patients with psoriasis compared with the controls (p = 0.0007) and inversely correlated with disease severity assessed by PASI score (R = -0.2935, p = 0.0407). Statistical analysis did not show significant relations between the count of EPCs and age, body mass index, gender, disease duration, blood pressure, extent of itching, severity and frequency of pruritus, presence of bruises, vitamin D supplementation and smoking habit. Conclusions: The results of our studies indicate that patients with psoriasis showed an increased mobilization of EPCs compared with healthy individuals which correlated negatively with disease severity.

Diurnal variations in tissue factor and tissue factor pathway inhibitor concentrations in relation to on-treatment platelet reactivity: an analysis of patients with acute myocardial infarction.

The aim of the study was to evaluate diurnal changes of tissue factor (TF) and tissue factor pathway inhibitor (TFPI) concentrations in relation to on-treatment platelet reactivity. The study group included 51 patients with acute myocardial infarction (AMI) treated with primary percutaneous coronary intervention and dual antiplatelet therapy. TF and TFPI concentrations were assessed using enzyme-linked immunosorbent assay kits. We found a significant increase of TF concentration in clopidogrel-resistant, but not clopidogrel-sensitive, patients at 10.00 a.m. (410.66 pg/mL) in comparison with 6.00 a.m. (250.99 pg/mL), 14.00 p.m. (255.12 pg/mL) and 19.00 p.m. (267.58 pg/mL). Moreover, TF concentration at 10.00 a.m. was 30% higher in clopidogrel-resistant than clopidogrel-sensitive patients (p = .043). We failed to demonstrate diurnal variation in TFPI concentration in clopidogrel-resistant patients. However, TFPI concentration in clopidogrel-sensitive patients was significantly higher at 10.00 a.m. as compared with other sampling points (p < .05). We observed a marked elevation in TF concentration at 10.00 a.m. only in aspirin-resistant patients and a significant increase in TFPI concentration at 10 a.m. only in aspirin-sensitive patients. Our findings suggest the presence of diurnal variations in TF and TFPI concentrations in AMI patients, with the highest thrombotic risk in patients with high on-treatment platelet reactivity in the midmorning.

The effects of humic water on endothelial cells under hyperglycemic conditions: inflammation-associated parameters.

Humic waters (HW) are globally unique, deep underground, dark-brown waters containing humic acids, and they present numerous therapeutic activities including anti-inflammatory. In the present study, we use HW from source in Poland. Diabetes has become an epidemic and is a risk factor of cardiovascular diseases. Hyperglycemia in diabetes is responsible for damaging of the endothelium and increases inflammation on the surface of the vascular lining. The inflammatory process in diabetes is associated with the secretion of inflammatory cytokines by endothelial cells, e.g., tumor necrosis factor alpha (TNFα) and interleukin 6 (IL-6), and with the reduction of cell proliferation. In the study, we used cultures of endothelial cells (HUVEC line-human umbilical vein endothelial cells) with the addition 30 mM/L of glucose in the culture medium which imitated the conditions of uncontrolled diabetes. The addition of HW in the proper volume to the culture medium causes reduction of inflammation by significant decrease in inflammatory cytokines such as TNFα and IL-6 and also leads to enhancement of the cell proliferation. It appears that the adverse effects of hyperglycemia on vascular endothelial cells may be corrected by addition of humic water. The above promising results of in vitro tests provide an opportunity to the possible use of humic water in the supportive treatment of endothelial dysfunction disorders in diabetes. However, this issue requires further clinical research.

Type 2 Diabetes and Cardiovascular Factors Contrasted with Fibrinolysis Disorders in the Blood of Patients with Peripheral Arterial Disease.

Background and objectives: Both in the pathogenesis of type 2 diabetes (DM 2) and Peripheral Arterial Disease (PAD), a vital role is played by endothelial dysfunction. Metabolic disorders found in DM 2 (hyperglycemia, insulin resistance), endothelial dysfunction, and increased inflammation lead to intensified atherothrombosis. The fibrinolysis system comprises a natural compensatory mechanism in case of hypercoagulability. The aim of this study was to assess concentrations of selected fibrinolysis parameters in the blood of patients with symptomatic PAD, including in particular concurrent DM 2 and other cardiovascular factors. Materials and Methods: In the group of 80 patients with PAD (27 F/53 M) and 30 healthy volunteers (10 F/20 M), the following parameters were measured: Concentrations of fibrinogen, tissue-Plasminogen Activator (t-PA Ag), Plasminogen Activator Inhibitor-1 (PAI-1 Ag), D-dimer, and platelet (PLT) count. Results: In the blood of patients with PAD and concomitant DM 2 significantly higher concentrations of fibrinogen were found in comparison with patients with PAD and without diabetes (p = 0.044). No significant impact was observed in individuals with atherosclerotic complications (manifested by coronary artery disease, atherosclerosis of cerebral arteries) and selected cardiovascular risk factors (smoking, LDL and triglyceride concentrations, BP values) on the levels of t-PA, PAI-1, D-dimer, and PLT count. It was found that t-PA Ag and PAI-1 Ag values tended to rise along with a BMI increase in the subgroups of subjects (with normal body mass, overweight, and obesity), but no statistically significant differences were observed. However, two significant positive correlations were reported between t-PA Ag and BMI, as well as between PAI-1 Ag and BMI. Conclusions: Type 2 diabetes in peripheral arterial disease affects the concentration of fibrinogen causing its increase, which is connected with the inflammation and prothrombotic process in the course of both conditions. The concurrence of atherosclerosis of coronary or cerebral arteries, smoking, LDL and TG concentrations, and BP value do not have a significant impact on the levels of analyzed fibrinolysis parameters. A positive correlation between BMI and t-PA Ag and PAI-1 Ag concentrations needs to be supported in further studies on a larger number of overweight and obese patients.

Activation of TF-Dependent Blood Coagulation Pathway and VEGF-A in Patients with Essential Thrombocythemia.

Background and objectives: Recent studies suggest that a vascular endothelial growth factor (VEGF-A) may be involved in the thrombotic process by stimulating the expression of tissue factor in vascular endothelial cells. Tissue factor (TF) can also stimulate the transcription of the gene encoding VEGF-A. The relationship between coagulation and angiogenesis in myeloproliferative neoplasms is not fully understood. The aim of this study was to evaluate the concentration of TF in relation to VEGF-A in the blood of patients with essential thrombocythemia (ET). Patients and methods: The study group consisted of 130, newly diagnosed patients with ET (mean age 61 years). The control group consisted of 35 healthy volunteers (mean age 51 years). Concentrations of VEGF-A, TF, and tissue factor pathway inhibitor (TFPI) were analysed using immunoenzymatic methods. TF and TFPI activities were performed using chromogenic assays. Results: The median concentration of TF Ag was 3-fold higher and the TF activity was more than 15-fold higher in ET patients than in normal individuals. There were no statistically significant differences in the TFPI concentration and activity between groups. VEGF-A was significantly increased in patients with ET (p < 0.000001). Analysis of correlations revealed a positive correlation between VEGF-A and TF Ag as well as a positive correlation between VEGF-A and TFPI activity. Conclusions: The simultaneous increase of TF concentration and activity, VEGF-A in the blood of patients with ET, as well as a positive correlation between the concentration of TF and VEGF-A demonstrates the coexistence of TF-dependent coagulation and activation of angiogenesis.

Low-level laser irradiation modifies the effect of hyperglycemia on adhesion molecule levels.

Endothelium plays a key role in maintaining vascular homeostasis by secreting active factors involved in many biological processes such as hemostasis, angiogenesis, and inflammation. Hyperglycemia in diabetic patients causes dysfunction of endothelial cells. Soluble fractions of adhesion molecules like sE-selectin and vascular cell adhesion molecule (sVCAM) are considered as markers of endothelial damage. The low-level laser therapy (LLLT) effectively supports the conventional treatment of vascular complications in diabetes, for example hard-to-heal wounds in patients with diabetic foot syndrome. The aim of our study was to evaluate the effect of low-energy laser at the wavelength of 635 nm (visible light) and 830 nm (infrared) on the concentration of adhesion molecules: sE-selectin and sVCAM in the supernatant of endothelial cell culture of HUVEC line. Cells were cultured under high-glucose conditions of 30 mM/L. We have found an increase in sE-selectin and sVCAM levels in the supernatant of cells cultured under hyperglycemic conditions. This fact confirms detrimental influence of hyperglycemia on vascular endothelial cell cultures. LLLT can modulate the inflammation process. It leads to a decrease in sE-selectin and sVCAM concentration in the supernatant and an increase in the number of endothelial cells cultured under hyperglycemic conditions. The influence of LLLT is greater at the wavelength of 830 nm.

Morphine delays and attenuates ticagrelor exposure and action in patients with myocardial infarction: the randomized, double-blind, placebo-controlled IMPRESSION trial.

AIMS: The currently available data indicate a drug-drug interaction between morphine and oral P2Y12 receptor inhibitors, when administered together. The aim of this trial was to assess the influence of infused morphine on pharmacokinetics and pharmacodynamics of ticagrelor and its active metabolite (AR-C124910XX) in patients with acute myocardial infarction. METHODS AND RESULTS: In a single-centre, randomized, double-blind trial, patients were assigned in a 1:1 ratio to receive intravenously either morphine (5 mg) or placebo, followed by a 180 mg loading dose of ticagrelor. Pharmacokinetics was determined with liquid chromatography tandem mass spectrometry and ticagrelor antiplatelet effects were measured with up to three different platelet function tests: vasodilator-stimulated phosphoprotein phosphorylation assay, multiple electrode aggregometry and VerifyNow. The pharmacokinetic and pharmacodynamic assessment was performed in 70 patients (35 in each study group). Morphine lowered the total exposure to ticagrelor and its active metabolite by 36% (AUC(0-12): 6307 vs. 9791 ng h/mL; P = 0.003), and 37% (AUC(0-12): 1503 vs. 2388 ng h/mL; P = 0.008), respectively, with a concomitant delay in maximal plasma concentration of ticagrelor (4 vs. 2 h; P = 0.004). Multiple regression analysis showed that lower AUC(0-12) values for ticagrelor were independently associated with the administration of morphine (P = 0.004) and the presence of ST-segment elevation myocardial infarction (P = 0.014). All three methods of platelet reactivity assessment showed a stronger antiplatelet effect in the placebo group and a greater prevalence of high platelet reactivity in patients receiving morphine. CONCLUSIONS: Morphine delays and attenuates ticagrelor exposure and action in patients with myocardial infarction. ClinicalTrials.gov Identifier: NCT02217878.

VEGF-A, sVEGFR-1, and sVEGFR-2 in BCR-ABL negative myeloproliferative neoplasms.

BACKGROUND AND OBJECTIVE: Data from the literature indicate the relationship between the bone marrow microvessel density and the blood parameters of angiogenesis. The aim of this study was to evaluate selected parameters of angiogenesis (VEGF-A, sVEGFR-1, and sVEGFR-2) and their correlations with white blood cells, platelets, and red blood cells. MATERIALS AND METHODS: The study included 72 patients (mean age, 61.84 years) with myeloproliferative neoplasms (MPNs): essential thrombocythemia (ET) (n=46), polycythemia vera (PV) (n=19), and primary myelofibrosis (PMF) (n=7). Serum VEGF-A, sVEGFR-1, and sVEGFR-2 were determined using the ELISA assay. RESULTS: We observed a significantly higher level of VEGF-A and reduced concentrations of sVEGFR-1 and sVEGFR-2 in the whole group of patients with MPNs as compared to controls. Detailed analysis confirmed significantly higher level of VEGF-A and lower concentration of sVEGFR-2 in each subgroups of MPNs patients. However, sVEGFR-1 concentrations were significantly lower only in PV and ET patients. CONCLUSIONS: The study showed an increased level of VEGF-A, which may indicate the intensity of neoangiogenesis in the bone marrow. Decreased sVEGFR-1 and sVEGFR-2 in the blood of patients with MPNs may reflect consumption of these soluble receptors.

Low-level laser irradiation effect on endothelial cells under conditions of hyperglycemia.

Diabetes mellitus is considered to be a very serious lifestyle disease leading to cardiovascular complications and impaired wound healing observed in the diabetic foot syndrome. Chronic hyperglycemia is the source of the endothelial activation. The inflammatory process in diabetes is associated with the secretion of inflammatory cytokines by endothelial cells, e.g., tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6). The method of phototherapy using laser beam of low power (LLLT-low-level laser therapy) effectively supports the conventional treatment of diabetic vascular complications such as diabetic foot syndrome. The aim of our study was to evaluate the effect of low-power laser irradiation at two wavelengths (635 and 830 nm) on the secretion of inflammatory factors (TNF-α and IL-6) by the endothelial cell culture-HUVEC line (human umbilical vein endothelial cell)-under conditions of hyperglycemia. It is considered that adverse effects of hyperglycemia on vascular endothelial cells may be corrected by the action of LLLT, especially with the wavelength of 830 nm. It leads to the reduction of TNF-α concentration in the supernatant and enhancement of cell proliferation. Endothelial cells play an important role in the pathogenesis of diabetes; however, a small number of studies evaluate an impact of LLLT on these cells under conditions of hyperglycemia. Further work on this subject is warranted.

Effect of LLLT on endothelial cells culture.

Growth factors as vascular endothelial growth factor (VEGF), produced by the endothelial cells, take an essential part in pathological and physiological angiogenesis. The possibility of angiogenesis modulation by application of laser radiation may contribute to the improvement of its use in this process. Thus, the aim of the study was to investigate the influence of low-level laser therapy (LLLT) on the proliferation of endothelial cells, secretion of VEGF-A and presence of soluble VEGF receptors (sVEGFR-1 and sVEGFR-2) in the medium after in vitro culture. Isolated human umbilical vein endothelial cells (HUVECs) were irradiated using a diode laser at a wavelength of 635 nm and power density of 1,875 mW/cm(2). Depending on radiation energy density, the experiment was conducted in four groups: I 0 J/cm(2) (control group), II 2 J/cm(2), III 4 J/cm(2), and IV 8 J/cm(2). The use of laser radiation wavelength of 635 nm, was associated with a statistically significant increase in proliferation of endothelial cells (p = 0.0041). Moreover, at 635-nm wavelength, all doses of radiation significantly reduced the concentration of sVEGFR-1 (p = 0.0197).

Insulin resistance as estimated by the homeostatic method at diagnosis of gestational diabetes: estimation of disease severity and therapeutic needs in a population-based study.

BACKGROUND: Chronic insulin resistance, exacerbated in the course of pregnancy, is an important pathophysiologic mechanism of gestational diabetes mellitus (GDM). We hypothesise that the degree of insulin resistance, assessed at diagnosis of GDM, is a parameter of its pathophysiologic heterogeneity and/or severity. Thus, it offers potential to open new avenues for the personalization of therapy in affected women. METHODS: 1254 Polish Caucasian women with GDM were recruited into the study. The following parameters were assessed in the course of the study: body mass index (BMI), parity, weight gain during pregnancy, glycated haemoglobin, glucose level during an oral glucose tolerance test (OGTT), insulin, insulin resistance and insulin secretion. The severity of GDM was assessed based on insulin use and daily insulin dose during gestation. In order to evaluate insulin secretion and insulin resistance the homeostatic method was used (HOMA-B and HOMA-IR, respectively). We compared all the metabolic parameters and methods of treatment of GDM in women subdivided by quartiles of insulin resistance. RESULTS: The HOMA-IR in the whole population ranged from 0.34 to 20.39. The BMI, fasting insulin, fasting glucose and insulin dose per day increased along with increasing quartiles (HOMA-IR > 1.29). We observed a decrease of HOMA-B in the third quartile (1.92-2.89) compared with the first quartile (0.34-1.29). Insulin treatment was associated with HOMA-IR (<1.29 vs. >2.89), OR: 3.37, fasting glucose (≤6.11 vs. >6.11 mmol/dl), OR: 2.61, age (≤30 vs. >30 y. o.), OR: 1.54, and BMI (<25 vs. ≥25 kg/m2), OR: 1.45. Maximum insulin dose was associated with HOMA-IR, OR: 2.00, after adjustment for family history of diabetes, and 2-h OGTT glucose. CONCLUSION: Insulin resistance assessed by the HOMA index at diagnosis is associated with the severity and pathophysiological heterogeneity of GDM. A HOMA-IR >1.29 points to the major role of insulin resistance, indicating the need for a treatment aimed at improving tissue sensitivity to insulin. A HOMA-IR 1.29-2.89 suggests reduced insulin secretion, which is an indication for the introduction of insulin therapy. A HOMA-IR >2.89 indicates insufficient compensation for insulin resistance, which suggests the need for a treatment aimed at improving susceptibility of tissues to insulin combined with insulin therapy.

Adiponectin and endothelial markers in postmenopausal women taking oral or transdermal hormone therapy.

OBJECTIVE: To assess the concentration of adiponectin, soluble E-selectin, soluble thrombomodulin and tissue activator plasminogen antigen in postmenopausal women who received oral or transdermal hormone therapy. DESIGN: Case-control study. SETTING: Polish university hospitals. POPULATION: Seventy-six healthy postmenopausal women. METHOD: Forty-six women who received oral (n = 26) or transdermal (n = 20) hormone therapy and a control group without such medication (n = 30), all aged 44-58 years. MAIN OUTCOME MEASURES: Plasma concentrations of adiponectin, soluble E-selectin, soluble thrombomodulin and tissue activator plasminogen antigen by enzyme-linked immunosorbent assay. RESULTS: We found a significantly higher concentration of adiponectin in women on oral and transdermal therapy in comparison to the control group and a significantly lower concentration of soluble E-selectin in women who received oral hormone therapy vs. the control group. A significantly higher concentration of tissue activator plasminogen antigen was obtained in the group of women using transdermal menopausal hormone therapy compared with those receiving oral therapy and with the control group. CONCLUSIONS: Reduced levels of soluble E-selectin in women using menopausal hormone therapy could lead to reduction in the intensity of expression of the adhesion factors on the surface of the vascular endothelium. Menopausal hormone therapy might have advantageous effects on vascular endothelial function through adiponectin. Transdermal therapy may have adverse effects associated with elevated tissue activator plasminogen antigen levels and thereby the higher risk of ischemic heart disease.

Impact of kidney donor hemostasis on risk of complications after transplantation--preliminary outcomes.

BACKGROUND: This study analyzes the influence the of kidney donor hemostasis on the risk of complications in the kidney recipient after transplantation. MATERIAL AND METHODS: We enrolled 38 deceased kidney donors, of whom 14 donors died from a physical injury and the others died from ischemic or bleeding central nervous system stroke. The donors were categorized into 2 subgroups. If the recipient's postoperative period proceeded smoothly, the kidney donor was assigned to the uncomplicated donors (UD) group. If the recipient's postoperative period was complicated, the donor was assigned to the complicated (CD) Group. The CD group of consisted of 9 donors who died from strokes or bleedings and 2 who died from physical injury. We examined the antithrombin (AT) protein C (PC), complexes of thrombin/antithrombin (TAT), fragments F1+2 of prothrombin (F1+2), plasminogen (Pl), complexes of plasmin/antiplasmin (PAP), and D-dimers (D-d). RESULTS: In the CD group had decreased activity of AT, PC, and Pl and increased activity of F1+2, TAT, and D-d. The UD group had a higher level of PAP. The CD group had evidence of intensive blood coagulation, but the UD group had evidence of fibrinolysis. Fisher's exact test revealed an increased risk in recipients who received a kidney from the CD group. CONCLUSIONS: The hemostasis of the kidney donors had a correlation with the occurrence of some complications in the kidney recipients, especially complications connected with activation of blood coagulation. It seems that the activation of fibrinolysis could be positive prognostic factor, but this requires further investigations.

The influence of selected demographic factors and wound location on the concentration of vascular endothelial growth factor (VEGF-A) in the wound healing process after neurosurgery: brief report.

The main aim of the work was to estimate the influence of selected demographic factors and wound location on the concentration of the vascular endothelial growth factor (VEGF-A) in patients after neurosurgical operations. The study included 20 adult patients who received a surgical treatment because of degenerative spine changes. Measurements of the concentration of the VEGF-A in the patients' blood serum were taken three times (the first time--before the operation; the second time--during the first 24 hours after surgery; and the third time--between the fifth and the seventh day after the operation). No statistically significant correlation between the concentration of VEGF-A in the patients' blood serum before and after the operation was noted. A statistically significant correlation between the concentration of VEGF-A in the individual measurements was found. It can be concluded that people with a higher concentration of VEGF-A before surgery obtained a higher concentration of VEGF-A in the measurements taken after the operation. There is a statistically significant link between the patient's age and the concentration of VEGF-A during the immediate postoperative period (the older the patient, the higher the level of VEGF-A is observed).

Triglycerides as an early pathophysiological marker of endothelial dysfunction in nondiabetic women with a previous history of gestational diabetes.

OBJECTIVE: To investigate whether baseline triglyceride levels are associated with early glucose dysregulation and/or cardiovascular risk in women with a previous history of gestational diabetes. DESIGN: Prospective postpregnancy cohort study. SETTING: Polish university hospitals. SAMPLE: Participants included 125 women with previous gestational diabetes and 40 women with normal glucose regulation during pregnancy. METHODS: All women were studied 2-24 months (mean 12 ± 10 months) after the index pregnancy. Women with previous gestational diabetes were divided into tertiles in accordance with baseline triglyceride levels. MAIN OUTCOME MEASURES: We assessed glucose regulation (oral glucose tolerance test), insulin resistance (homeostasis model assessment), markers of endothelial dysfunction (soluble: intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, tissue plasminogen activator antigen, von Willebrand factor antigen), fibrinolysis (plasminogen activator inhibitor antigen), inflammation (high-sensitivity C-reactive protein) and lipid levels. RESULTS: Women with previous gestational diabetes (78% normal glucose regulation, 22% impaired glucose tolerance) had a high cardiometabolic risk profile compared with control women (100% normal glucose regulation). Baseline triglycerides >0.83 mmol/l were associated with a higher prevalence of impaired glucose tolerance, higher high-sensitivity C-reactive protein and triglyceride/high-density lipoprotein-cholesterol ratio. Triglycerides >1.22 mmol/l were associated with higher body fat indexes, higher insulin resistance, higher levels of endothelial dysfunction biomarkers, higher plasminogen activator inhibitor antigen and dyslipidemia. Only E-selectin was independently associated with triglyceride levels. CONCLUSIONS: Baseline triglyceride levels are a cardiovascular risk marker as well as a pathophysiological parameter independently associated with endothelial dysfunction in nondiabetic women with previous gestational diabetes at 2-24 months after an index pregnancy. Normalization of triglycerides should be included in preventive therapy after a pregnancy complicated by gestational diabetes.

Endothelial cell markers in patients with pseudoexfoliation syndrome.

The aim of the study was the assessment of the von Willebrand antigen (vWF Ag), E-selectin, and P-selectin concentration in blood plasma of patients with pseudoexfoliation syndrome (PEX). The group studied comprised 30 patients with PEX, aged from 50 to 86 years (mean 73, SD ± 8 years). Patients with cardiovascular and cerebrovascular diseases, diabetes mellitus, infectious disease, cancer, renal or liver insufficiency, connective tissue disease, current smoking, and hormone, antiplatelet, hypolipidemic, antioxidant, or antihypertensive drug therapy were excluded from the study. Each subject underwent a complete ophthalmological examination. Venous blood samples from the cubital vein were taken into sodium citrate solution. VWF Ag, sP-selectin, and sE-selectin concentration were determined by a commercially available enzyme-linked immunosorbent assay (MedSystems, Diagnostica Stago/Roche, R&D). Concentrations of vWF Ag, soluble E-selectin, and soluble P-selectin in blood plasma in the study group were compared with the levels in blood plasma in the control group. No significant differences were found between the groups. Our results indicate that there might be no correlation between PEX and such endothelial cell markers as vWF Ag, sP-selectin, and sE-selectin concentrations. Since the study size is limited, further investigations to confirm that there is no association between endothelial dysfunction in PEX and risk of future cardiovascular disease are necessary.

Diurnal Oscillations of Fibrinolytic Parameters in Patients with Acute Myocardial Infarction and Their Relation to Platelet Reactivity: Preliminary Insights.

There is limited information about diurnal changes in fibrinolysis parameters after acute myocardial infarction (AMI) and their relationship with on-treatment platelet reactivity. The aim of this study was to assess tissue plasminogen activator (t-PA), plasminogen activator inhibitor type-1 (PAI-1), α2-antiplasmin (α2-AP) activity, and plasmin-antiplasmin (PAP) complexes in 30 AMI patients taking dual antiplatelet therapy (DAPT), i.e., acetylsalicylic acid and clopidogrel. Fibrinolytic parameters were assessed at four time points (6 a.m., 10 a.m., 2 p.m., and 7 p.m.) on the third day after AMI using immunoenzymatic methods. Moreover, platelet reactivity was measured using multiple-electrode aggregometry, to assess potential differences in fibrinolytic parameters in low/high on-aspirin platelet reactivity and low/high on-clopidogrel platelet reactivity subgroups of patients. We detected significant diurnal oscillations in t-PA and PAI-1 levels in the whole study group. However, PAP complexes and α2-AP activity were similar at the analyzed time points. Our study reveals a potential impact of DAPT on the time course of fibrinolytic parameters, especially regarding clopidogrel. We suggest the presence of diurnal variations in t-PA and PAI-1 concentrations in AMI patients, with the highest levels midmorning, regardless of platelet reactivity. Significantly elevated levels of PAI-1 during the evening hours in clopidogrel-resistant patients may increase the risk of thrombosis.

Tissue factor-dependent coagulation activation in intracranial neoplasms: a comparative study.

The aim of the study was to investigate the concentration and activity of tissue factor (TF) and Tissue factor pathway inhibitor (TFPI) as well as the concentration of thrombin-antithrombin (TAT) complexes in patients with primary and metastatic intracranial neoplasms. The study included 69 patients with an average age of 62 years. Twenty-one patients were diagnosed with gliomas, 18 meningioma stage II (M) patients, and 30 metastatic brain tumour cases (Meta). The control group consisted of 30 individuals with a mean age of 57 years. In the plasma of all the participants and in tumour tissue-derived homogenate, the concentrations and activities of TF, TFPI, the concentration of TAT complexes and the concentration of total protein were measured. The results were converted per 1 mg of protein. The concentration of TF was over 80 times higher in the tumour tissue-derived homogenate in respect to patients' plasma levels. Plasma TF activity in intracranial cancer patients was almost six times higher compared with noncancer counterparts, while in the tumour tissue-derived homogenate it was more than 14 times higher than in the intracranial cancer patients' plasma, whereas the concentration of TFPI in the tumour tissue-derived homogenate was significantly lower than in the patients' plasma. However, a significantly higher TFPI activity in the tumour tissue derived than in the patients' plasma was reported. The high concentration and activity of TF, along with the coexisting low concentration and activity of TFPI in the plasma of intracranial tumour patients, is associated with a higher prothrombotic risk in these patients.

Diurnal variation in platelet inhibition by clopidogrel.

Morning increase in the occurrence of myocardial infarction, stroke and sudden cardiac death is a well-recognized phenomenon, which is in line with a morning enhancement of platelet aggregation. We investigated whether platelet inhibition during clopidogrel and aspirin therapy varies during the day. Fifty-nine consecutive patients (45 men and 14 women) with first ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary interventions (pPCI) on dual antiplatelet therapy were prospectively enrolled into the study. Blood samples were collected 4 days after start of clopidogrel treatment at 6.00 a.m., 10.00 a.m., 2.00 p.m. and 7.00 p.m. Arachidonic acid and adenosine diphosphate (ADP)-induced platelet aggregation were assessed by impedance aggregometry. Platelet inhibition by clopidogrel was lowest in the midmorning: median ADP-induced platelet aggregation was 55%, 17% and 27% higher at 10.00 a.m. compared to 6.00 a.m., 2.00 p.m. and 7.00 p.m., respectively (p < 0.002). Nonresponsiveness to clopidogrel defined according to the device manufacturer was 2.4-fold more frequent in the midmorning than in the early morning. We observed a more pronounced midmorning increase in ADP-induced platelet aggregation in diabetic patients when compared to non-diabetics. In contrast, no diurnal variation in the antiplatelet effect of aspirin was observed. In conclusion, in patients presenting with STEMI undergoing pPCI, platelet inhibition by clopidogrel is less strong in the midmorning hours. This periodicity in platelet aggregation in patients on dual antiplatelet therapy should be taken into consideration when assessing platelet function in clinical studies.

Tissue-type plasminogen activator and plasminogen activator inhibitor type 1 in patients with symptomatic lower extremity artery disease.

BACKGROUND: Lower extremity artery disease (LEAD) involves progressive arterial narrowing manifested by intermittent claudication (IC). LEAD entails endothelial dysfunction and fibrinolytic disorders. In the current study, we analyze the selected parameters of the fibrinolytic system in the blood of patients with symptomatic LEAD depending on clinical parameters. METHODS: The test group was comprised of 80 patients with diagnosis of LEAD based on Ankle-Brachial Index (ABI) test (27 female/53 male) with an average age of 63.5±9 years. The control group included 30 healthy, non-smoking volunteers (10 female/20 male), with the median age of 56±6 years. The research material - venous blood - was sampled to determine the concentrations of tissue-type plasminogen activator (t-PA Ag), plasminogen activator inhibitor type 1 (PAI-1 Ag), D-dimer, fibrinogen, and platelet count (PLT). RESULTS: We found elevated concentrations of t-PA Ag, PAI-1 Ag, D-dimer, and fibrinogen in the plasma of subjects with symptomatic LEAD. Various stages of the Fontaine classification demonstrated a gradual, statistically significant increase in the concentrations of fibrinogen and PLT count as the disease progressed. More so, in the subgroup of LEAD patients aged ≥65 years, we observed significantly higher levels of D-dimer than in the group of younger subjects. In addition to that, the LEAD group demonstrated negative correlations of IC distance, fibrinogen concentrations, and PLT count, negative correlations of ABI at rest and concentrations of D-dimer and PLT count, as well as positive correlations between age and D-dimer levels. CONCLUSIONS: High t-PA Ag concentrations in LEAD patients suggest damage to the endothelium which comprises the main source of this factor. With high PAI-1 Ag levels, inactive fibrinolytic t-PA-PAI-1 complexes are formed. Increasing fibrinogen concentrations at the subsequent stages in accordance with the Fontaine classification, indicate increasing inflammation. Moreover, heightened values of D-dimer reflect an increased secondary fibrinolysis activation as patients get older and impaired extremity vascularization, manifested by the decreasing ABI, progresses.