The aim of the study was to detect changes of both the QT dispersion and T-loop morphology resulting from the changed spatial position of the heart during pregnancy. Electrocardiographic and vectorcardiographic recordings were obtained from 37 healthy women 19-36 years old in the 36th to 40th week of physiological pregnancy and 2 to 6 days after delivery. The same recordings were obtained from 18 healthy women of the same age. The average QT dispersion (±S.D.) in normal subjects was significantly lower (34±12 ms) than in those in late pregnancy (73±18 ms) (P<0.001). The average amplitude of T-loop (Ta) in women in late pregnancy was significantly (P<0.001) smaller (532±98 mV) and the width of T-loop (Tw) was wider (21.24±11.48 deg) than in the control group (793±114 mV and 7.17±3.02 deg, respectively). The partial post-partum restoration of all parameters was not significant. In all groups, the QT dispersion was significantly correlated with Tw but not with Ta. According to these results we can conclude that the QT dispersion is an indirect reflection of the complete process of ventricular repolarization, reflected in the morphology of the T-loop., M. Lechmanová, O. Kittnar, M. Mlček, J. Slavíček, A. Dohnalová, Š. Havránek, J. Kolařík, A. Pařízek., and Obsahuje bibliografii
We discuss the representability almost everywhere (a.e.) in C of an irreducible algebraic function as the Cauchy transform of a signed measure supported on a finite number of compact semi-analytic curves and a finite number of isolated points. This brings us to the study of trajectories of the particular family of quadratic differentials A(z − a)(z − b)×(z − c)−2 dz2. More precisely, we give a necessary and sufficient condition on the complex numbers a and b for these quadratic differentials to have finite critical trajectories. We also discuss all possible configurations of critical graphs., Mohamed Jalel Atia, Faouzi Thabet., and Obsahuje seznam literatury
The aim of this study was to evaluate macroscopically, histologically and immunohistochemically the quality of newly formed tissue in iatrogenic defects of articular cartilage of the femur condyle in miniature pigs treated with the clinically used method of microfractures in comparison with the transplantation of a combination of a composite scaffold with allogeneic mesenchymal stem cells (MSCs) or the composite scaffold alone. The newly formed cartilaginous tissue filling the defects of articular cartilage after transplantation of the scaffold with MSCs (Group A) had in 60 % of cases a macroscopically smooth surface. In all lesions after the transplantation of the scaffold alone (Group B) or after the method of microfractures (Group C), erosions/fissures or osteophytes were found on the surface. The results of histological and immunohistochemical examination using the modified scoring system according to O’Driscoll were as follows: 14.7±3.82 points after transplantations of the scaffold with MSCs (Group A); 5.3±2.88 points after transplantations of the scaffold alone (Group B); and 5.2±0.64 points after treatment with microfractures (Group C). The O’Driscoll score in animals of Group A was significantly higher than in animals of Group B or Group C (p<0.0005 both). No significant difference was found in the O’Driscoll score between Groups B and C. The treatment of iatrogenic lesions of the articular cartilage surface on the condyles of femur in miniature pigs using transplantation of MSCs in the composite scaffold led to the filling of defects by a tissue of the appearance of hyaline cartilage. Lesions treated by implantation of the scaffold alone or by the method of microfractures were filled with fibrous cartilage with worse macroscopic, histological and immunohistochemial indicators., A. Nečas ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
LED lamps with various combinations of red (R) and blue (B) wavelengths were used to supplement sunlight for the growth of a heat-resistant (HR) and heat-sensitive (HS) recombinant inbred lines (RIL) of lettuce. The RB-LED ratios were 100R:0B (0B), 92R:8B (8B), 84R:16B (16B), and 76R:24B (24B) with an equal PPFD of 100 μmol m-2 s-1. The greatest leaf expansion rates were observed at 8B for both genotypes. All HR-RILs had similar values of growth parameters and specific leaf area (SLA). However, higher values of growth parameters were observed in HS-RIL with 0B, 8B, and 16B than that under 24B and sunlight. Furthermore, HS-RIL had higher SLA under 0B compared to other conditions. Photosynthetic light-use efficiency and maximal oxygen evolution rate were the lowest under 8B for both genotypes. The quality of LED lighting, if provided, seemed to implicate genotype dependence, probably as a result of their different sensitivities to heat stress., T. W. Choong, J. He, L. Qin, S. K. Lee., and Obsahuje bibliografii
In this study, we presented a new approach for quantification of bicarbonate (HCO3-) molecules bound to PSII. Our method, which is based on a combination of membrane-inlet mass spectrometry (MIMS) and 18O-labelling, excludes the possibility of "non-accounted" HCO3- by avoiding (1) the employment of formate for removal of HCO3- from PSII, and (2) the extremely low concentrations of HCO3-/CO2 during online MIMS measurements. By equilibration of PSII sample to ambient CO2 concentration of dissolved CO2/HCO3-, the method ensures that all physiological binding sites are saturated before analysis. With this approach, we determined that in spinach PSII membrane fragments 1.1 ± 0.1 HCO3- are bound per PSII reaction center, while none was bound to isolated PsbO protein. Our present results confirmed that PSII binds one HCO3- molecule as ligand to the non-heme iron of PSII, while unbound HCO3- optimizes the water-splitting reactions by acting as a mobile proton shuttle., K. Tikhonov, D. Shevela, V. V. Klimov, J. Messinger., and Obsahuje bibliografické odkazy
In the seventies of the past century ballistocardiography had been thought to be obsolete in cardiology for impossibility of objective calibration. In the present work the quantitative ballistocardiography (Q-BCG) for measurement of systolic force (F) and minute cardiac force (MF) in sitting subject was described. The new principle of piezoelectric transducer enabled to register the force caused by the heart and blood movement, which was not measured before. The calibration proved that the action of the force on the transducer was expressed quantitatively without the amplitude-, time-, and phase deformation. The close relationship of skeletal muscle force and F was proved. The F and MF changed under different physiological conditions (age, partial pressure of oxygen, body weight, skeletal muscle force). It was shown that the systolic force (F) and minute cardiac force (MF) are the physiological parameters neurohumorally regulated similarly as the heart rate or systolic volume., Z. M. Trefný ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy