To propose a test to evaluate endothelial function, based on VO 2 on-transition kinetics in sub -anaerobic threshold (AT) constant load exercise, we tested healthy subjects and patients with ischemic -hypertensive cardiopathy by two cardiopulmonary te sts on a cycle ergometer endowed with an electric motor to overcome initial inertia: a pre-test and, after at least 24 h, one 6 min constant load exercise at 90 % AT. We measured net phase 3 VO2-on kinetics and, by phase 2 time constant (τ), valued endothe lial dysfunction. We found shorter τ in repeated tests, shorter time between first and second test, by persisting endothelium -dependent arteriolar vasodilatation and/or several other mechanisms. Reducing load to 80 % and 90 % AT did not produce significant changes in τ of healthy volunteers, while in heart patients an AT load of 70 %, compared to 80 % AT, shortened τ(∆=4.38±1.65s, p=0.013). In heart patients, no correlation was found between NYHA class, ejection fraction (EF), and the two variables derived from incremental cycle cardio - pulmonary exercise, as well as between EF and τ; while NYHA class groups were well correlated w ith τ duration (r=0.92, p=0.0001). Doxazosin and tadalafil also significantly reduced τ. In conclusion, the O2 consumption kinetics during the on transition of constant load exercise below the anaerobic threshold are highly sensitive to endothelial functi on in muscular microcirculation, and constitute a marker for the evaluation of endothelial dysfunction. and D. Maione, A. F. G. Cicero, S. Bacchelli, E. R. Cosentino, D. Degli Esposti, D. N. Manners, E. R. Rinaldi, M. Rosticci, R. Senaldi, E. Ambrosioni, C. Borghi.
The aim of our study was to explore the effects of regular aerobic exercise on anthropome tric, biochemical and hormonal parameters and mRNA expression of selected factors involved in metabolic regulations in subcutaneous adipose tissue of patients with obesity. Fifteen obese wome n with arterial hypertension underwent a three-month exercise program consisting of 30 min of aerobic exercise 3 times a we ek. Fifteen healthy lean women with no intervention served as a control group. Obese group underwent anthropometric measurements, blood sampling, subcutaneous adipose tissue (SCAT) biopsy and 24-h blood pressure monitoring at baseline and after three months of exercise, while control group was examined only once. At baseline, obese group had increased SCAT expression of proinflammatory cytokines and adipokines relative to control group. Three months of regular exercise improved anthropometric parameters, decreased CRP, blood glucose and HOMA-IR, while having no significant effect on lipid profile and blood pressure. Gene expressions in SCAT were not affected by physical activity with the exce ption of increased aquaporin-3 mRNA expression. We conclude that three months of regular exercise decrease systemic subc linical inflammation with only minor influence on the blood pressure and the endocrine function of subcutaneous fat., P. Trachta, J. Drápalová, P. Kaválková, V. Toušková, A. Cinkajzlová, Z. Lacinová, M. Matoulek, T. Zelinka, J. Widimský Jr., M. Mráz, M. Haluzík., and Obsahuje bibliografii
Patch clamp recordings carried out in the inside-out configuration revealed activity of three kinds of channels: nonselective cation channels, small-conductance K+ channels, and large-conductance anion channels. The nonselective cation channels did not distinguish between Na+ and K+. The unitary conductance of these channels reached 28 pS in a symmetrical concentration of 200 mM NaCl. A lower value of this parameter was recorded for the small-conductance K+ channels and in a 50-fold gradient of K+ (200 mM/4 mM) it reached 8 pS. The high selectivity of these channels to potassium was confirmed by the reversal potential (-97 mV), whose value was close to the equilibrium potential for potassium (-100 mV). One of the features of the large - conductance anion channels was high conductance amounting to 493 pS in a symmetrical concentration of 200 mM NaCl. The channels exhibited three subconductance levels. Moreover, an increase in the open probability of the channels at voltages close to zero was observed. The anion selectivity of the channels was low, because the channels were permeable to both Cl - and gluconate - a large anion. Research on the calcium dependence revealed t hat internal calcium activates nonselective cation channels and small-conductance K+ channels, but not large - conductance anion channels., M. Koselski, A. Olszewska, A. Hordyjewska, T. Małecka-Massalska, K. Trebacz., and Obsahuje bibliografii
Thyroid nodules are a very frequent pathology among common population. Despite the vast majority of them are of benign origin, the incidence of thyroid cancer is currently rather rising. Although there are several risk factors of thyroid cancer and several clinical, ultrasound, biochemical and molecular diagnostic markers, the exact mechanisms of thyroid oncogenesis and the linkage between thyroid nodule ultrasound appearance and its biological character remain unclear. While ionizing radiation is the only one well-known risk factor for thyroid cancer, the significance of some others remains unclear. The aim of our review was to discuss some not completely known pathophysiological mechanisms involved in thyroid oncogenesis as hypothyroidism, mutations of genes regulating cell proliferation, thyroid autoimmunity and pregnancy and to describe pathophysiological background of some ultrasound markers of thyroid cancer (size, echogenicity, vascularization, calcifications and stiffness). Better knowledge in this field is crucial for development of novel diagnostic techniques and therapeutic approaches. For exampl e, the analysis of BRAF, RAS and other mutations in cytological samples may help to distinction between follicular thyroid carcinoma and follicular thyroid adenoma and may signific antly decrease the number of unnecessary surgery among patients with thyroid nodules. Alternatively, the different malign cells growth, angiogenesis, destructions of thyroid follicles, reparative changes, growth retardation, fibrosis and increased interstitial fluid pressure implicate the typical ultrasound appearance of papillary thyroid cancer (hypoechogenicity, irregular vascularization, microcalcifications, stiffness) which is essential to catch the suspicious nodules on the basis of their ultrasound appearance among large amount of benign nodules., J. Krátký, H. Vítková, J. Bartáková, Z. Telička, M. Antošová, Z. Límanová, J. Jiskra., and Obsahuje bibliografii
The sequence of changes in circulating immune cells and in free radical production was studied during the small intestine reperfusion. Rat small intestine ischemia/reperfusion was induced by a 45 min superior mesenteric artery occlusion followed by a 4-hour reperfusion. Samples of peripheral blood were collected every 20 min during reperfusion. While the number of polymorphonuclear leukocytes increased significantly both in the sham-operated controls and the experimental group (about 400 % at the end of reperfusion), a decrease in lymphocyte counts to 60 % was observed in the experimental group only. Although there were no changes in the counts of total T lymphocytes, a significant reduction in B cell counts was observed. Flow-cytometrical measurements showed no changes in the Tc subpopulation, while the Th subpopulation increased in the experimental group only. Free radical generation in blood (luminometric measurements) increased gradually and reached an eight-fold level by the end of reperfusion in both groups. Thus, it has been shown that the increase in free radical production is mainly due to the increased number of polymorphonuclear leukocytes mobilized already at the initial stages of reperfusion. The reduction in B lymphocyte population is probably due to homing mechanisms., J. Hamar, I. Rácz, M. Číž, A. Lojek, É. Pállinger, J. Fűrész., and Obsahuje bibliografii
Enhanced expression of tissue factor (TF) may result in thrombosis contributing to acute clinical consequences of coronary artery disease. Several studies demonstrated elevated plasma levels of TF in patients with acute coronary syndrome (ACS). The aim of our study was to compare the concentrations of TF in coronary sinus (CS), proximal part of the left coronary artery (LCA) and peripheral vein (PV) of patients with ACS and stable coronary artery disease (SCAD). Time course of the TF plasma levels in PV was followed on day 1 and day 7 after index event of ACS presentation and was compared to day 0 values. No heparin was given prior to the blood sampling. Twenty-nine patients in the ACS group (age 63.6±10.8 years, 20 males, 9 females) and 24 patients with SCAD (age 62.3±8.1 years, 21 males, 3 females) were examined. TF plasma level was significantly higher in patients with ACS than in those with SCAD (239.0±99.3 ng/ml vs. 164.3±114.2 ng/ml; p=0.016). There was no difference in TF plasma levels in PV, CS and LCA (239.0± 99.3 ng/ml vs. 253.7±131.5 ng/ml vs. 250.6±116.4 ng/ml, respectively). TF plasma levels tended to decrease only non-significantly on the day 7 (224.4± 109.8 ng/ml). Significant linear correlation between TF and high sensitivity CRP (hs-CRP) levels on day 0 was found. In conclusion, TF plasma levels are elevated in patients with ACS not only locally in CS but also in systematic circulation. Our data support the relationship between TF production and proinflammatory mediators., J. Bis ... [et al.]., and Obsahuje seznam literatury
a1_The tissue factor plays a crucial role in initiating blood coagulation after plaque rupture in patients with acute coronary syndrome. It is abundant in atherosclerotic plaques. Moreover, P-selectin, some cytokines, endotoxin and immune complexes can stimulate monocytes and induce the tissue factor expression on their surface. The aim of the study was to compare plasma levels of the tissue factor, tissue factor pathway inhibitor, P-selectin, E-selectin and ICAM-1 in patients with acute myocardial infarction, unstable angina pectoris, stable coronary artery disease and normal control subjects. In addition, plasma levels of the tissue factor, tissue factor pathway inhibitor, P-selectin, E-selectin and ICAM-1 were measured in the blood withdrawn from the coronary sinus in a subgroup of patients with unstable angina pectoris and stable coronary artery disease in which the difference between concentrations in the coronary sinus and systemic blood was calculated. A significant increase in tissue factor pathway inhibitor plasma levels was detected in patients with acute myocardial infarction (373.3±135.1 ng/ml, p<0.01) and unstable angina pectoris (119.6±86.9 ng/ml, p<0.05) in contrast to the patients with stable coronary artery disease (46.3±37.5 ng/ml) and normal subjects (45.1±14.3 ng/ml). The plasma levels of tissue factor pathway inhibitor were significantly increased both in the coronary sinus and systemic blood in the patients with unstable angina pectoris. There was only a non-significant trend to higher plasma levels of the tissue factor in patients with acute myocardial infarction and unstable angina pectoris as compared to the patients with stable coronary artery disease and normal subjects, the values being 129.1±30.2 pg/ml, 130.5±57.8 pg/ml, 120.2±45.1 pg/ml and 124.9±31.8 pg/ml, respectively., a2_Plasma levels of soluble P-selectin was only slightly, but non-significantly higher in patients with unstable angina pectoris and stable coronary artery disease (184.2±85.4 ng/ml and 201.6±67.9 ng/ml, respectively) than in patients with the acute myocardial infarction (157.4±88.4 ng/ml) or normal subjects (151.4±47.1 ng/ml). The difference in plasma levels of soluble ICAM-1 between the blood withdrawn from the coronary sinus and systemic circulation correlated significantly with the corresponding difference in plasma levels of soluble P-selectin and E-selectin. In conclusion, the tissue factor and the tissue factor pathway inhibitor play a crucial role in the initiation of arterial thrombosis. The tissue factor pathway inhibitor levels are increased both in the systemic blood and in the coronary sinus of patients with the acute coronary syndrome., M. Malý, J. Vojáček, V. Hraboš, M. Semrád, M. Mates, J. Kvasnička, P. Salaj, V. Durdil., and Obsahuje bibliografii
Smoking is the most important cardiovascular (CV) risk factor. Stopping smoking halves the CV risk. Every clinician should provide a brief intervention with smokers. Intensive treatment should be available to those who need it. There are 37 Centers for Tobacco Dependence in the Czech Republic, which offer treatment including a psychobehavioral intervention and pharmacotherapy (varenicline, nicotine, bupropion). Czech physicians, pharmacists and nurses are regularly educated about smoking cessation. We describe the results of intensive treatment offered by our centers. Treatment includes screening (1 h), an intervention (2 h), and follow-up visits during the next 12 months. Among 3532 patients, 34.3 % had CO-validated abstinence at 12-months (including 489 patients who attended the screening visit + only the 12-month follow up visit). Among patients who underwent the intervention, the abstinence rate was 38.2 %. The majority of patients who underwent the intervention (N=2470) used some form of pharmacotherapy. After one year, the abstinence rate was 43.4 %, compared to 15.9 % (N=573) without pharmacotherapy. Only 28 % of patients came on the recommendation of a physician. Despite the decrease in CV risk following smoking cessation and the effectiveness of treatment, centers are underutilized., E. Králíková, A. Kmeťová, L. Štěpánková, K. Zvolská, V. Felbrová, S. Kulovaná, Z. Bortlíček, M. Blaha, K. Fraser., and Obsahuje bibliografii
Hypertrophied hearts are known for increased risk of arrhythmias and are linked with reduced ischemic tolerance. However, still little is known about state characterized only by increased left ventricle (LV) mass fraction. Seventeen isolated rabbit hearts with various LV mass were divided into two groups according to LV weight/heart weight ratio (LVW/HW ratio), namely group H and L (with higher and lower LVW/HW ratio, respectively) and underwent three short cycles of global ischemia and reperfusion. The differences in electrogram (heart rate, QRSmax, mean number, onset and dominant form of ventricular premature beats) and in biochemical markers of myocardial injury (creatine kinase, lactate dehydrogenase - LDH) and lipid peroxidation (4-hydroxy-2-nonenal - 4-HNE) were studied. As compared to group L, hearts in group H exhibited lower tolerance to ischemia expressed as higher incidence and severity of arrhythmias in the first ischemic period as well as increase of LDH and 4-HNE after the first reperfusion. In the third cycle of ischemia-reperfusion, the preconditioning effect was observed in both electrophysiological parameters and LDH release in group H. Our results showed consistent trends when comparing changes in electrograms and biochemical markers. Moreover, 4-HNE seems to be good potential parameter of moderate membrane alteration following ischemia-reperfusion injury., M. Hlaváčová, V. Olejníčková, M. Ronzhina, T. Stračina, O. Janoušek, M. Nováková, P. Babula, J. Kolářová, I. Provazník, H. Paulová., and Obsahuje bibliografii
Clinical and experimental studies have repeatedly indicated that overloaded hearts have a higher vulnerability to ischemia/reperfusion injury. The aim of the present study was to answer the question whether the degree of tolerance to oxygen deprivation in hearts of spontaneously hypertensive rats (SHR) may be sex-dependent. For this purpose, adult SHR and their normotensive control Wistar Kyoto (WKY) rats were used. The isolated hearts were perfused according to Langendorff at constant pressure (proportionally adjusted to the blood pressure in vivo). Recovery of contractile parameters (left ventricular systolic, diastolic and developed pressure as well as the peak rate of developed pressure) was measured during reperfusion after 20 min of global no-flow ischemia in 5 min intervals. Mean arterial blood pressure was measured by direct puncture of carotid artery under light ether anesthesia in a separate group of animals. The degree of hypertension was comparable in both sexes of SHR. The recovery of contractile functions in SHR males and females was significantly lower than in WKY rats during the whole investigated period. There was no sex difference in the recovery of WKY animals; on the other hand, the recovery was significantly better in SHR females than in SHR males. It may be concluded that the hearts of female SHR are more resistant to ischemia/reperfusion injury as compared with male SHR. This fact could have important clinical implications for the treatment of cardiovascular disease in women., J. Bešík, O. Szárszoi, J. Kuneš, I. Netuka, J. Malý, F. Kolář, J. Pirk, B. Ošťádal., and Obsahuje bibliografii a bibliografické odkazy