The aims were to explore the effect of head-up tilt (HUT) to 30 and 60 degrees on hemodynamics and tissue oxygenation in anesthetized healthy swine. The data serve as a reference for a study of resuscitation efficacy at HUT such as during transport. Nine healthy swine (49±4 kg) were anesthetized and multiple sensors including myocardial pressure-volume loops catheter, carotid flow probe, blood pressure catheters, near infrared spectroscopy (NIRS) tissue oximetry and mixed venous oximetry (SVO2) catheter were introduced and parameters continuously recorded. Experimental protocol consisted of baseline in supine position (15 min), 30 degrees HUT (15 min), recovery at supine position (15 min) and 60 degrees HUT (5 min). Vacuum mattress was used for body fixation during tilts. We found that 30 and 60 degrees inclination led to significant immediate reduction in hemodynamic and oximetry parameters. Mean arterial pressure (mm Hg) decreased from 98 at baseline to 53 and 39, respectively. Carotid blood flow dropped to 47 % and 22 % of baseline values, end diastolic volume to 49 % and 53 % and stroke volume to 47 % and 45 % of baseline. SVO2 and tissue oximetry decreased by 17 and 21 percentage points. The values are means. In conclusions, within minutes, both 30 and 60 degrees head-up tilting is poorly tolerated in anesthetized swine. Significant differences among individual animals exist., M. Mlcek, J. Belohlavek, M. Huptych, T. Boucek, T. Belza, S. Lacko, P. Krupickova, M. Hrachovina, M. Popkova, P. Neuzil, O. Kittnar., and Obsahuje bibliografii
Heart failure has become the most widely studied syndrome in cardiology over the recent years. Despite the encouraging achievements by angiotensin converting enzyme (ACE) inhibitors, the mortality of patients with chronic heart failure remains high. There are several factors which can potentially be responsible for the fact that about 80% of patients with a failing heart defy protection by ACE inhibitors: different activation of tissue and systemic renin-angiotensin system (RAS) in a particular heart disease and the distinct ability of various ACE inhibitors to block cardiac ACE, alternative pathways for angiotensin II formation (chymase), genetic polymorphism of the RAS system and the complexity of neuroendocrine activation. Moreover, chronic heart failure can provoke disturbances in the reactivity of peripheral vessels and metabolism of striated muscles. These factors may then potentiate the vicious circle of heart failure. New therapeutic approaches, which could further reduce the mortality in patients with heart failure involve angiotensin II type 1 receptor antagonists, beta-blockers, aldosterone antagonists and blockers of the endothelin receptor. A number of questions associated with functions of the RAS still remain open and their solution could be of substantial benefit for patients with a failing heart., F. Šimko, J. Šimko., and Obsahuje bibliografii
The objective was to establish whether an intravascular volume increase leads to a heart rate (HR) increase without increased sympathetic tonus. HR changes at rest and at deep breathing (6/min - simulated increase of atrial filling pressure) were measured in patients after heart transplantation. Evaluation of dependency of HR changes on breathing depth was done through a new time series methodology. The data was evaluated through graphs displaying a significant increase in the graph area at deep breathing, when compared with breathing at rest (p < 0.01). We presume that an increase in HR corresponds to increased intravascular volume and malfunctioning kidneys., M. Souček, T. Kára, P. Jurák, J. Halámek, L. Špinarová, J. Meluzím, J. Toman, I. Řiháček, J. Šumbera, P. Fráňa., and Obsahuje bibliografii
The aim of the study was to evaluate short-term heart rate variability (HRV) as an index of cardiac autonomic control in rats with lipopolysaccharide (LPS)-induced endotoxemia. Animals were injected intraperitoneally with LPS (100 μg/kg b.w.) and control group with an equivalent volume of saline. ECG recordings were done before (base) and 60, 120, 180, 240 and 300 min after LPS or saline administration. HRV magnitude was quantified by time and frequency-domain analysis (mean RR interval, SDRR, RMSSD, spectral powers in low (LF) and high frequency (HF) bands. Heart tissue homogenates and plasma were analyzed to determine interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α) and oxidative stress level (TBARS). Administration of lipopolysaccharide was followed by continuous rise in colonic body temperature compared to saline-treated controls. Endotoxemia in rats was accompanied by significant decrease in HRV spectral activity in high-frequency range at maximal body temperature (logHFpower: 1.2±0.5 vs. 1.9± 0.6 ms2, P<0.01). Increased IL-6 was found in heart tissue homogenates of LPS rats (8.0±0.6 vs. 26.4±4.8 pg/ml, (P<0.05). In conclusions, reduced HRV in HF band may indicate a decreased parasympathetic activity in LPS-induced endotoxemia as basic characteristics of altered cardiac control during response to endotoxemia., I. Zila, D. Mokra, J. Kopincova, M. Kolomaznik, M. Javorka, A. Calkovska., and Obsahuje bibliografii
Heart rate (HR) and heart rate variability (HRV) in newborns is influenced by genetic determinants, gestational and postnatal age, and other variables. Premature infants have a reduced HRV. In neonatal HRV evaluated by spectral analysis, a dominant activity can be found in low frequency (LF) band (combined parasympathetic and sympathetic component). During the first postnatal days the activity in the high frequency (HF) band (parasympat hetic component) rises, together with an increase in LF band and total HRV. Hypotrophy in newborn can cause less mature autonomic cardiac control with a higher contribution of sympathetic activity to HRV as demonstrated by sequence plot analysis. During quiet sleep (QS) in newborns HF oscillations increase - a phenomenon less expressed or missing in premature infants. In active sleep (AS), HRV is enhanced in contrast to reduced activity in HF band due to the rise of spectral activity in LF band. Comparison of the HR and HRV in newborns born by physiological vaginal delivery, without (VD) and with epidural anesthesia (EDA) and via sectio cesarea (SC) showed no significant differences in HR and in HRV time domain parameters. Analysis in the frequency domain re vealed, that the lowest sympathetic activity in chronotropic cardiac chronotropic regulation is in the VD group. Different neonatal pathological states can be associated with a reduction of HRV and an improvement in the health conditions is followed by ch anges in HRV what can be use as a possible prognostic marker. Examination of heart rate variability in neonatology can provide information on the maturity of the cardiac chronotropic regulation in early postnatal life, on postnatal adaptation and in pathological conditions about the potential dysregulation of cardiac function in newborns, especially in preterm infants., K. Javorka, Z. Lehotska, M. Kozar, Z. Uhrikova, B. Kolarovszki, M. Javorka, M. Zibolen., and Obsahuje bibliografii
The purpose of this study was to investigate the influence of heat treatment on glucocorticoid (GC) -induced myopathy. Eight -week - old Wistar rats were randomly assigned to the control, Dex, and Dex + Heat groups. Dexamethasone (2 mg/kg) was injected subcutaneously 6 days per week for 2 weeks in the Dex and Dex + Heat group. In the Dex + Heat group, heat treatment was performed by immersing hindlimbs in water at 42 °C for 60 min, once every 3 days for 2 weeks. The extensor digitorum longus muscle was extracted following 2 weeks of experimentation. In the Dex + Heat group, muscle fiber diameter, capillary/muscle fiber ratio, and level of heat shock protein 72 were significantly higher and atrogene expression levels were significantly lower than in the D ex group. Our results suggest that heat treatment inhibits the development of GC -induced myopathy by decreas ing atrogene expression and increasing angiogenesis., Y. Morimoto, Y. Kondo, H. Kataoka, Y. Honda, R. Kozu, J. Sakamoto, J. Nakano, T. Origuchi, T. Yoshimura, M. Okita., and Obsahuje bibliografii
In this study, lipoic acid and heat shock treatments were applied to C2C12 myotubes and Sprague-Dawley rats to investigate changes in the heat shock protein 70 (HSP70) and glucose transporter 4 (GLUT4) in 4 different skeletal muscle groups. The results of western blotting indicated that treatment of lipoic acid for 24 h, heat-shock and combined lipoic acid and heat-shock which all increased the level of HSP70 substantially in C2C12 myotubes. However, either lipoic acid or heat-shock did not increase the level of GLUT4 in C2C12 myotubes. In an in vitro migration assay, lipoic acid increased wound migration only when it was applied for 3 h. Moreover, our in vivo results revealed that lipoic acid did not increase HSP70 and GLUT4 in all 4 different skeletal muscles. Furthermore, heat-shock increased HSP70 in all 4 different muscle groups, and heat-shock treatment alone increased the GLUT4 in the soleus muscle only, suggesting that the GLUT4 increased by heat-shock was slow-twitch muscle specific. Collectively, our results indicated that heat-shock is critical factor that modulates GLUT4 and HSP70 in the skeletal muscle of rats., P.-F. Wu, S.-C. Luo, L.-C. Chang., and Obsahuje bibliografii
We investigated hematopoiesis in untreated and ionizing radiation-exposed cyclooxygenase-2-deficient (COX-2 KO) mice. We performed a complex hematological analysis of 16 parameters in untreated COX-2 KO male mice or COX-2 KO male mice irradiated with the dose of 4 Gy of γ-rays and their wildtype littermates. At baseline, hematopoiesis was increased in COX-2-deficient mice, but attenuated by irradation in COX-2- deficient mice compared to wildtype. To conclude, the antiinflammatory action of the COX-2 genetic disruption plays a positive role in hematopoiesis under basal conditions but is detrimental following radiation exposure., M. Hofer, Z. Hoferová L. Dušek, K. Souček, A. Gruzdev., and Obsahuje bibliografii
The purpose of the study was to describe and compare normal and 5-fluorouracil (5-FU)-suppressed hematopoiesis in adenosine A3 receptor knock-out (A3AR KO) mice and their wild-type (WT) counterparts. To meet the purpose, a complex hematological analysis comprising nineteen peripheral blood and bone marrow parameters was performed in the mice. Defects previously observed in the peripheral blood erythrocyte and thrombocyte parameters of the A3AR KO mice were confirmed. Compartments of the bone marrow progenitor cells for granulocytes/ macrophages and erythrocytes were enhanced in the control, as well as in the 5-FU-administered A3AR KO mice. 5-FU-induced hematopoietic suppression, evaluated on day 2 after the administration of the cytotoxic drug, was found to be significantly deeper in the A3AR KO mice compared with their WT counterparts, as measured at the level of the bone marrow progenitor cells. The rate of regeneration, as assessed between days 2 and 7 after 5-FU administration, was observed in the population of the granulocyte/macrophage progenitor cells to be higher in the A3AR KO mice in comparison with the WT ones. The increased depth of 5-FU-induced suppression in the compartments of the hematopoietic progenitor cells in the A3AR KO mice represents probably a hitherto undescribed further consequence of the lack of adenosine A3 receptors and indicates its synergism with the pharmacologically induced cytotoxic action of 5-FU., M. Hofer, M. Pospíšil, L. Dušek, Z. Hoferová, D. Komůrková., and Obsahuje bibliografii
Positive effects of repeated administration of diclofenac, an inhibitor of prostaglandin synthesis, in terms of prevention of tumor development and stimulation of hematopoiesis have been observed in C3H mice transplanted subcutaneously with G:5:113 fibrosarcoma cells. Fourteen-day treatment with diclofenac (3.75 mg/kg/day) started from day 5 after tumor cell transplantation. Measurements of tumors and hematological examinations were performed on day 30. The results strongly suggest the possibility that inhibitors of prostaglandin synthesis (non-steroidal anti-inflammatory drugs) may be used in oncological practice where the observed effects are highly desirable., M. Hofer, Z. Hoferová, P. Fedoročko, N. O. Macková., and Obsahuje bibliografii