Addiction to tobacco results in an imbalance of endocrine homeostasis in both sexes. This can also have impacts on fertility problems. The male reproductive system is less susceptible than that of females, with a worsening spermiogram in smokers, the most cited effect in the literature. However, the literature is inconsistent as to the effects of smoking on steroid hormone levels in men, and there is very little data on the effects of quitting smoking in men. In this study we followed 76 men before quitting smoking, and then after 6, 12, and 24 weeks and 1 year of abstinence. We measured basic anthropomorphic data and steroid hormone levels along with steroid neuroactive metabolites using GC-MS. We demonstrate lower androgen levels in men who smoke, and these changes worsened after quitting smoking. There was a drop in SHBG already in the first week of non-smoking, and levels continued to remain low. Male smokers have lower androgen levels compared to non-smokers. The lower the initial level of androgen, the lower the likelihood of success in quitting smoking. Changes in steroid hormones proved to be a promising marker for the prediction of success in quitting smoking., H. Jandikova, M. Duskova, K. Simunkova, B. Racz, M. Hill, E. Kralikova, K. Vondra, L. Starka., and Obsahuje bibliografii
The dissociation between egocentric and allocentric reference frames is well established. Spatial coding relative to oneself has been associated with a brain network distinct from spatial coding using a cognitive map independently of the actual position. These differences were, however, revealed by a variety of tasks from both static conditions, using a series of images, and dynamic conditions, using movements through space. We aimed to clarify how these paradigms correspond to each other concerning the neural correlates of the use of egocentric and allocentric reference frames. We review here studies of allocentric and egocentric judgments used in static two- and three-dimensional tasks and compare their results with the findings from spatial navigation studies. We argue that neural correlates of allocentric coding in static conditions but using complex three-dimensional scenes and involving spatial memory of participants resemble those in spatial navigation studies, while allocentric representations in two-dimensional tasks are connected with other perceptual and attentional processes. In contrast, the brain networks associated with the egocentric reference frame in static two-dimensional and three-dimensional tasks and spatial navigation tasks are, with some limitations, more similar. Our review demonstrates the heterogeneity of experimental designs focused on spatial reference frames. At the same time, it indicates similarities in brain activation during reference frame use despite this heterogeneity., Sofiia Moraresku, Kamil Vlcek., and Obsahuje bibliografii
The solid-state NMR measurements play an indispensable role in studies of interactions between biological membranes and peptaibols, which are amphipathic oligopeptides with a high abundance of α-aminobutyric acid (Aib). The solid-state NMR investigations are important in establishing the molecular models of the pore forming and antimicrobial properties of peptaibols, but rely on certain simplifications. Some of the underlying assumptions concern the parameters describing the 15N NMR chemical shielding tensor (CST) of the amide nitrogens in Aib and in conventional amino acids. Here the density functional theory (DFT) based calculations were applied to the known crystal structure of one of peptaibols, Ampullosporin A, in order to explicitly describe the variation of the 15N NMR parameters within its backbone. Based on the DFT computational data it was possible to verify the validity of the assumptions previously made about the differences between Aib and other amino acids in the isotropic part of the CST. Also the trends in the magnitudes and orientations of the anisotropic components of the CST, as revealed by the DFT calculations of the full periodic structure of Ampullosporin A, were thoroughly analyzed, and may be employed in future studies of peptaibols., J. Czernek, J. Brus., 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
The purpose of this study was to compare markers of glycolytic metabolism in response to the Wingate test and the incremental test in road and mountain bike cyclists, who not different performance level and aerobic capacity. All cyclists executed the Wingate test and incremental test on a cycle ergometer. Maximal power and average power were determined during the Wingate test. During the incremental test the load was increased by 50 W every 3 min, until volitional exhaustion and maximal aerobic power (APmax), maximal oxygen uptake (VO2max), and time of VO2max plateau (Tplateau) were determined. Post-exercise measures of oxygen uptake (VO2post), carbon dioxide excretion, (VCO2post), and the ratio between VCO2/VO2 (RERpost) were collected for 3 min immediately after incremental test completion. Arterialized capillary blood was drawn to measure lactate (La-) and hydrogen (H+) ion concentrations in 3 min after each test. The data demonstrated significant differences between mountain bike and road cyclists for Tplateau, VO2post, VCO2post, La- which was higher-, and RERpost which was lower-, in mountain bike cyclists compare with road cyclists. No differences were observed between mountain bike and road cyclists for APmax, VO2max, H+ and parameters measured in the Wingate test. Increased time of VO2max plateau concomitant to larger post-exercise La- and VO2 values suggests greater anaerobic contribution during incremental testing efforts by mountain bike cyclists compared with road cyclists., P. Hebisz, R. Hebisz, J. Borkowski, M. Zatoń., 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
The protective role of nutrition factors such as calcium, vitamin D and vitamin K for the integrity of the skeleton is well understood. In addition, integrity of the skeleton is positively influenced by certain trace elements (e.g. zinc, copper, manganese, magnesium, iron, selenium, boron and fluoride) and negatively by others (lead, cadmium, cobalt). Deficiency or excess of these elements influence bone mass and bone quality in adulthood as well as in childhood and adolescence. However, some protective elements may become toxic under certain condition s, depending on dosage (serum concentration), duration of treatment and interactions among individual elements. We review the beneficial and toxic effects of key elements on bone homeostasis., I. Zofkova, M. Davis, J. Blahos., and Obsahuje bibliografii
The high prevalence of obesity and related metabolic complications has inspired research on adipose tissues. Three kinds of adipose tissues are identified in mammals: brown adipose tissue (BAT), beige or brite adipose tissue and white adipose tissue (WAT). Beige adipocytes share some characteristics with brown adipocytes such as the expression of UCP1. Beige adipocytes can be activated by environmental stimuli or pharmacological treatment, and this change is accompanied by an increase in energy consumption. This process is called white browning, and it facilitates the maintenance of a lean and healthy phenotype. Thus, promoting beige adipocyte development in WAT shows promise as a new strategy in treating obesity and related metabolic consequences. In this review, we summarized the current understanding of the regulators and hormones that participate in the development of brown fat and white fat browning., Jianmei Zhang, Huixiao Wu, Shizhan Ma, Fei Jing, Chunxiao Yu, Ling Gao, Jiajun Zhao., and Obsahuje bibliografii
Hypertriglyceridemia is an important marker of increased levels of highly atherogenic rem nant -like particles. The importance of lowering plasma levels of triglycerides (TG) has been called into question many times, but currently it is considered an integral part of residual cardiovascular risk reduction strategies. Lifestyle changes (improved diet and increased physical activity) are effective TG lowering measures. Pharmacological treatment usually starts with statins, although associated TG reductions are typically modest. Fibrates are currently the drugs of choice for hyperTG, frequently in c ombination with statins. Niacin and omega -3 fatty acids improve control of triglyceride levels when the above measures are inadequately effective. Some novel therapies including anti- sense oligonucleotides and inhibitors of microsomal triglyceride transfer protein have shown significant TG lowering efficacy. The current approach to the management of hypertriglyceridemia is based on lifestyle changes and, usually, drug combinations (statin and fibrate and/or omega -3 fatty acids or niacin)., M. Vrablík, R. Češka., and Obsahuje bibliografii
Ulinastatin [or called as urinary trypsin inhibitor (UTI)] plays a role in regulating neurological deficits evoked by transient cerebral ischemia. However, the underlying mechanisms still need to be determined. The present study was to examine the effects of UTI on autophagy, Nrf2-ARE and apoptosis signal pathway in the hippocampus in the process of neurological functions after cerebral ischemia using a rat model of cardiac arrest (CA). CA was induced by asphyxia followed by cardiopulmonary resuscitation (CPR) in rats. Western blot analysis was employed to determine the expression of representative autophagy (namely, Atg5, LC3, Beclin 1), p62 protein (a maker of autophagic flux), and Nrf2-ARE pathways. Neuronal apoptosis was assessed by determining expression levels of Caspase-3 and Caspase-9, and by examining terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL). The modified neurological severity score (mNSS) and spatial working memory performance were used to assess neurological deficiencies in CA rats. Our results show that CA amplified autophagy and apoptotic Caspase-3/Caspase-9, and downregulated Nrf2-ARE pathway in the hippocampus CA1 region. Systemic administration of UTI attenuated autophagy and apoptosis, and largely restored Nrf2-ARE signal pathway following cerebral ischemia and thereby alleviated neurological deficits with increasing survival of CA rats. Our data suggest that UTI improves the worsened protein expression of autophagy and apoptosis, and restores Nrf2-ARE signals in the hippocampus and this is linked to inhibition of neurological deficiencies in transient cerebral ischemia. UTI plays a beneficial role in modulating neurological deficits induced by transient cerebral ischemia via central autophagy, apoptosis and Nrf2-ARE mechanisms., Xiao-Ming Jiang, Jing-Hai Hu, Lu-Lu Wang, Chi Ma, Xu Wang, Xiao-Liang Liu., and Obsahuje bibliografii