Apolipoprotein (apo) B-100 is a key protein compound of plasma lipid metabolism. This protein, as a sole component of LDL particles, to a great extent controls the homeostasis of LDL cholesterol in the plasma. Therefore, this protein and its structural variants play an important role in development of hyperlipidemia and atherosclerosis. Intensive research into the structure and biological functions of apoB-100 has led to identification of its complete structure as well as the responsible binding sites. With the development of the methods of molecular biology, some structural variants of the apoB-100 protein that directly affect its binding properties have been described. These are mutations leading to amino acid substitution at positions 3500 (R3500Q and R3500W) and 3531 (R3531C) that have been shown to decrease the binding affinity of apoB-100 in vitro. However, only the former mutations have been unequivocally demonstrated to cause hyperlipidemia in vivo. This minireview is aimed to discuss the impact of apoB-100 and its structural variants on plasma lipid metabolism and development of hyperlipidemia., M. Vrablík, R. Češka, A. Hořínek., and Obsahuje bibliografii
A characteristic of mast cells is the degranulation in response to various stimuli. Here we have investigated the effects of various physical stimuli in the human mast-cell line HMC-1. We have shown that HMC-1 express the transient receptor potential channels TRPV1, TRPV2 and TRPV4. In the whole-cell patchclamp configuration, increasing mechanical stress applied to the mast cell by hydrostatic pressure (–30 to –90 cm H2 O applied via the patch pipette) induced a current that could be inhibited by 10 µM of ruthenium red. This current was also inhibited by 20 µM SKF96365, an inhibitor that is among TRPV channels specific for the TRPV2. A characteristic of TRPV2 is its activation by high noxious temperature; temperatures exceeding 50 °C induced a similar ruthenium-red-sensitive current. As another physical stimulus, we applied laser light of 640 nm. Here we have shown for the first time that the application of light (at 48 mW for 20 min) induced an SKF96365-sensitive current. All three physical stimuli that led to activation of SKF96365-sensitive current also induced pronounced degranulation in the mast cells, which could be blocked by ruthenium red or SKF96365. The results suggest that TRPV2 is activated by the three different types of physical stimuli. Activation of TRPV2 allows Ca2+ ions to enter the cell, which in turn will induce degranulation. We, therefore, suggest that TRPV2 plays a key role in mast-cell degranulation in response to mechanical, heat and red laser-light stimulation., D. Zhang ... [et al.]., and Obsahuje seznam literatury
The aim of our study was to evaluate possible effect of ABCB1, and OPRM1 polymorphisms on the efficacy and safety of remifentanil in women undergoing elective cesarean section under general anesthesia. Women received remifentanil (1 μg/kg i.v.) 30 s prior to the induction to standardized general anesthesia. The ABCB1 (rs2032582, rs1045642) and OPRM1 (rs1799971) polymorphisms were analyzed from maternal peripheral blood. The basal hemodynamic and demographic parameters in the study population (n=54) were similar in all the subgroups. The median ± SD increase of systolic blood pressure at 5 min from the baseline was practically completely abolished in homozygous carriers of ABCB1 variants in comparison with wildtype subjects -2.67±25.0 vs. 16.57±15.7 mm Hg, p<0.05 for rs2032582, and 2.00±23.9 vs. 22.13±16.8 mm Hg, p<0.05, for rs1045642, respectively. While no neonate belonging to ABCB1 wild-type homozygous or OPRM1 variant carrying mothers needed any resuscitative measure, 10.5 % of the neonates belonging to OPRM1 wild-type homozygous mothers received resuscitative support similarly as 11.1 %, and 12.5 % of neonates of mothers carrying variants of rs2032582, and rs1045642, respectively. Decreased stabilizing effects of remifentanil on maternal hemodynamics has been observed in ABCB1 wild type mothers, while the adaptation of the neonates was clinically worse in OPRM1 wild type, and ABCB1 variant allele carriers., H. Bakhouche, P. Noskova, S. Svetlik, O. Bartosova, J. Ulrichova, J. Kubatova, P. Marusicova, A. Parizek, J. Blaha, O. Slanar., and Obsahuje bibliografii
The biochemical model of excitation-contraction coupling in cardiomyocyte is presented and the validity of simulations of both physiological and pathological processes is discussed. The model of regulatory and actomyosin subsystems, even if it is rather simple in its regulatory subunit, gives results well consistent with experimental data. Specifically, intracellular free calcium levels ([Ca2+]i) were computed under various states of sarcoendoplasmic reticular Ca2+-ATPase (SERCA2) and compared to experimental findings. Computed results reproduced well both the increase in resting [Ca2+]i level and the attenuation of [Ca2+]i decline commonly observed in heart failure. Thus the computational simulations could help to identify core relations in studied systems by comparing results obtained using similar models of various complexities., M. Mlček, J. Neumann, O. Kittnar, V. Novák., and Obsahuje bibliografii
It is well known that the consumption of moderate doses of alcohol leads to the increase of HDL-cholesterol (HDL-C). Atheroprotectivity of HDL particles is based primarily on their role in reverse cholesterol transport (RCT). In the study with a crossover design 13 male volunteers were studied in two different regimens: i) drinking of 36 g alcohol daily and ii) drinking only non-alcoholic beverages, to test whether alcohol-induced increase of HDL cholesterol can affect cholesterol efflux (CHE) from cell culture of labeled human macrophages. Alcohol consumption induced significant (p<0.05) increases of HDL cholesterol from 1.25±0.32 to 1.34±0.38 mmol/l and Apo A1 from 1.34±0.16 to 1.44±0.19 g/l. These changes were combined with a slight increase of cholesterol efflux from 13.8±2.15 to 14.9±1.85 % (p=0.059). There were significant correlations between individual changes of HDL-C and Apo A1 concentrations and individual changes of CHE (0.51 and 0.60, respectively). In conclusion, moderate alcohol consumption changes the capacity of plasma to induce CHE only at a border line significance., I. Králová Lesná ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
We evaluate the mRNA expression of monocarboxylate transporters 1 and 4 (MCT1 and MCT4) in skeletal muscle (soleus, red and white gastrocnemius), heart and liver tissues in mice submitted to a single bout of swimming exercise at the maximal lactate steady state workload (MLSSw). After 72 h of MLSS test, the animals were submitted to a swimming exercise session for 25 min at individual MLSSw. Tissues and muscle samples were obtained at rest (control, n=5 ), immediately (n=5 ), 5 h (n=5 ) and 10 h (n=5 ) after exercise for determination of the MCT1 and MCT4 mRNA expression (RT-PCR). The MCT1 mRNA expression in liver increased after 10 h in relation to the control, immediate and 5 h groups, but the MCT4 remained unchanged. The MCT1 mRNA expression in heart increased by 31 % after 10 h when compared to immediate, but no differences were observed in relation to the control group. No significant differences were observed for red gastrocnemius in MCT1 and MCT4 mRNA expression. However, white gastrocnemius increased MCT1 mRNA expression immediately when compared to rest, 5 and 10 h test groups. In soleus muscle, the MCT1 mRNA expression increased immediately, 5 and 10 h after exercise when compared to the control. In relation to MCT4 mRNA expression, the soleus increased immediately and 10 h after acute exercise when compared to the control group. The soleus, liver and heart were the main tissues that showed improved the MCT1 mRNA expression, indicating its important role in controlling MLSS concentration in mice., G. G. de Araujo, C. A. Gobatto, F. de Barros Manchado-Gobatto, L. F. M. Teixeira, I. G. M. dos Reis, L. C. Caperuto, M. Papoti, S. Bordin, C. R: Cavaglieri, R. Verlengia., and Obsahuje bibliografii
Glucose-dependent insulinotropic peptide (GIP) contributes to incretin effect of insulin secretion which is impaired in Type 2 diabetes mellitus. The aim of this study was to introduce a simple meal test for evaluation of GIP secretion and action and to examine GIP changes in Type 2 diabetic patients. Seventeen Type 2 diabetic patients, 10 obese non-diabetic and 17 nonobese control persons have been examined before and after 30, 60 and 90 min stimulation by meal test. Serum concentrations of insulin, C-peptide and GIP were estimated during the test. Impaired GIP secretion was found in Type 2 diabetic patients as compared with obese non-diabetic and non-obese control persons. The AUCGIP during 90 min of the meal stimulation was significantly lower in diabetic patients than in other two groups (p<0.03). Insulin concentration at 30 min was lower in diabetic than in non-diabetic persons and the GIP action was delayed. The ΔIRI/ΔGIP ratio increased during the test in diabetic patients, whereas it progressively decreased in obese and nonobese control persons. Simple meal test could demonstrate impaired GIP secretion and delayed insulin secretion in Type 2 diabetic patients as compared to obese non-diabetic and nonobese healthy control individuals., J. Škrha., and Obsahuje bibliografii a bibliografické odkazy
Patch clamp method developed more than 30 years ago is widely used for investigation of cellular excitability manifested as transmembrane ionic current and/or generation of action potentials. This technique could be applied to measurement of ionic currents flowing through individual (single) ion channels or through the whole assembly of ion channels expressed in the whole cell. Whole cell configuration is more common for measurement of ion currents and the only one enabling measurement of action potentials. This method allows detailed analysis of mechanisms and structural determinants of voltagedependent gating of ion channels as well as regulation of channel activity by intracellular signaling pathways and pharmacological agents., M. Karmažínová, L'. Lacinová., and Obsahuje bibliografii a bibliografické odkazy
The multi-functional proteins, insulin-like growth factor-I (IGF-I) and leptin were present in seminal plasma from different species. Concentrations of IGF-I in equine and porcine semen were 20 and 17.5 ng/ml, respectively. Seminal plasma concentrations of leptin were 1 ng/ml in human and 11 ng/ml in porcine samples., B. R. Lackey, S. L. Gray, D. M. Henricks., and Obsahuje bibliografii
The Vasotrac monitor provides non-invasive near-continuous blood pressure monitoring and is designed to be an alternative to direct intra-arterial blood pressure (BP) measurement. As compared to radial artery invasive BP and upper arm noninvasive BP, Vasotrac readings have been found to have a good agreement with them. However, discrepancies have been reported when rapid changes in BP exist. In the present study we compared BP measured by the Vasotrac monitor on the radial artery with that recorded on the finger arteries by the differential oscillometric device allowing measurement on the beat-to-beat basis. Comparisons were performed on the mean arterial pressure (MAP) level. Special attention was paid to the signal conditioning before comparison of pressures of different temporal resolution. Altogether 383 paired MAP measurements were made in 14 healthy subjects. Based on all 383 paired measurements, the MAP values measured at the radial artery at rest were 4.8±6.0 mm Hg higher than those measured on fingers. The observed difference between the Vasotrac and differential oscillometric device can be explained by different measurement sites. This result is consistent with previous investigations, and the Vasotrac monitor can be considered to adequately track relatively rapid MAP changes on the radial artery. Attention should be paid to a proper signal conditioning before comparison of results obtained by different devices., K. Jagomägi ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy