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Konstitutivní modelování tepenné stěny
Horný, L. ; Chlup, Hynek ; Adámek, T. ; Zitny, R. ; Macková, H.
Inflation tests and uni–axial extension tests of arterial tissue were performed. Experimental data were used in nonlinear regression analysis to identify material model. Arterial tissue was assumed to be incompressible hyperelastic material. 5–parameter strain energy density function based on combination of isotropic Neo–Hookean expression and Fung–type orthotropic expression was used. Computational model for material parameters identification was based on thick–wall tube with axial pre–strains. Residual strains were included. Internal structure of arterial wall was not considered. Fitted material models correspond to experimental data very well.
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Mutation Analysis in MLBR /Major Ligand Binding Regions/ of COL1A1 gene of the Czech Individuals with Osteogenesis Imperfecta, Type I-IV Diagnosis.
Šormová, Lucie ; Mazura, Ivan (advisor) ; Včelák, Josef (referee)
Osteogenesis imperfecta is an inherited disorder caused mainly by collagen type I genes mutations, COL1A1 and COL1A2. These mutations affect especially connective tissue. Disease is characterized by fragile bones, deformations and increased frequency of fractures. It's worldwide extensive disorder regardless of age, sex, nationality or races. The incidence is 1: 16 - 20 000 births. Currently, we described nine clinically distinct forms of Osteogenesis imperfecta. Only the first four types OI, type I-IV, are caused by collagen type I genes mutations . In these nine types there are distinguished mild and severe forms. Type II and III are lethal forms, death occur offen during prenatal period or in the first days of the life affected individuals. Characteristic clinical features of collagen forms OI are an increased incidence of fractures, deformations of bones, blue sclera, hearing loss, Dentinogenesis imperfecta small or subnormal growth (Marini, 2010). This study alignment is mainly the description of the clinical forms, exploring the molecular basis of disease and determine the relationship between the type and position of the mutation and the resulting phenotype of affected individuals. We have analysed exons 31-40, including associated non-coding regions, of the COL1A1 gene (so-called MLBR =...
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Actin nucleation in plant cell
Schiebertová, Petra ; Schwarzerová, Kateřina (advisor) ; Cvrčková, Fatima (referee)
The ability of plant cells to nucleate actin is important especially for dynamic of intracellular movements of organelles and vesicles, cell structure and growth organization and coordination of endo- and exocytosis . Actin nucleation means the development of new actin filaments from G-actin. Actin associated proteins - Arp2/3 complex and formins serve for this purpose. Arp2/3 complex polymerizes new "daughter " filament from the side of the "parent" filament at an angle of 70 degrees and after the nucleation remains at minus end of filaments, thus inducing branching of filaments. Nucleation by Arp2/3 complex further requires nucleation promoting factors - NPFs. Deletion of subunits of Arp2/3 complex is often lethal in animal cells. On the other hand, deletion results in rather mild phenotype in plants. Formins catalyze the formation of direct actin fibers and remain on the plus end of the fiber after nucleation. There are multiple isoforms of formins in plants than in animals, which suggest an important role of formins in plants. New actin nucleators Cobl, Lmod, Spire, JMY and APC containing WH2 (WASP homology 2) domain were identified in non-plant cells. This type of actin nucleation was not described in plants. Kew words: Actin, Arp2/3 complex, formins, Scar/WAVE, Cobl, Lmod, Spire
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Tests for desing of mortars and renders compatible with existing historic material
Válek, Jan ; Slížková, Zuzana
Design of masonry mortars and renders for repair of historic structures includes tests and testing procedures which serve for evaluation of compatibility between existing material and repair mixtures. Paper describes current possibilities of tests and analysis of historic and new mortars. The authors stem from published definitions of compatibility and emphasize a necessity to take into account also more detailed technical specifications, e.g. position of evaluated material in structure, type of structure, material exposure conditions, degree of deterioration of material and its ability to serve its original function.
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Contribution of ten ectodomain cysteine residues to function of ATP-gated P2X4 receptor
Tvrdoňová, Vendula ; Teisinger, Jan (referee) ; Zemková, Hana (advisor)
Extracellular adenosine-5'-triphosphate (ATP), released from damaged cells or coreleased as a cotransmitter from synaptic vesicles, acts on its plasma membrane receptors termed purinergic. Purinergic P2X receptors are ATP-gated cation channels. To date seven P2X isoforms designated P2X1-7 have been cloned that are organized as trimeric homomers or heteromers. All P2X subunits share a similar structure consisting of a large extracellular loop, two transmembrane domains and intracellular N- and C- termini. An additional structural feature is conserved aminoacids, these include ten conserved cysteine residues in the extracellular loop. All ectodomain cysteines form disulfide bonds which are organized in two areas: three disulfide bridges are localized in the N-termini half and two in the C-termini half at P2X receptor. ATP binding pocket is apparently localized between two neighbouring subunits. The aim of this Diploma Thesis was to examine the relevance of ectodomain cysteine residue and/or disulfide bonds for the expression, function and ATP binding properties of the P2X receptor. All ten, one by one, ectodomain cysteines were substituted by alanines and ATP-induced currents was recorded in HEK293 cells expressing wild-type P2X4 receptor and its mutants. Low responsible or nonfunctional mutants...
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Modulation of synaptic transmission, studies on spinal cord slices in vitro
Mrózková, Petra ; Paleček, Jiří (advisor) ; Krůšek, Jan (referee)
Modulation of a synaptic transmission in the spinal cord dorsal horn plays a key role in nociceptive signalling, especially in states of pathological pain. The goal of this study was to develop a method for calcium imaging in spinal cord slices in vitro. This method allowed us to record changes of intracellular free calcium ions concentration (iCa2+ ), that are a major mediator of neuronal plasticity. In this work, we have focused on application of this method in a conventional fluorescence microscope and on the role of different neuromodulators of synaptic activity. Changes of iCa2+ induced by dorsal root electrical stimulation were recorded altogether in 744 dorsal horn (lamina I and II) neurons. In the first series of experiments, stimulation protocols activating preferentially A and A + C dorsal root fibers were used and long-term stability of the calcium responses was verified. The dorsal root stimulation induced in the neurons fast and delayed type of calcium response. Application of AMPA and NMDA receptors antagonists, CNQX (50μM) and MK801 (45μM), reduced the calcium response amplitude and confirmed the importance of glutamate receptors in synaptic activation. In several experiments the effect of capsaicin a TRPV1 receptors agonist, application was tested. Application of even low...
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Molecular genetic and clinical neurological exmaination in autosomal recessive forms of hereditary neuropathies Charcot-Marie-Tooth
Baránková, Lucia ; Bojar, Martin (advisor) ; Martásek, Pavel (referee) ; Voháňka, Stanislav (referee)
The Charcot-Marie-Tooth (CMT) diseases are the most common inherited neuropathies. CMT is characterized clinically by distal muscle wasting and weakness, reduced reflexes and impaired distal sensation and by a sensory motor neuropathy neurophysiologically. The severity of the disease varies enormously depending to a large extent on the underlying genetic defect. The current clinical classification of CMT is done using electrophysiological criteria into type 1 (demyelinating) and type 2 (axonal) and further sub-classification is done according to inheritance pattern. A solely genetic classsification is not possible at present as all the causative genes for CMT are not known. Autosomal recessive CMT (AR CMT) forms are rare in European populations. The responsible genes have been discovered just in recent years. The disease has usually early onset and fast progressing and severe course. Mutations in GDAP1 gene (ganglioside- induced differentation associated proteine-1) soon showed to be the most common cause of CMT in families with AR pedigrees. They were found in patients with demyelinating (CMT4A) as well as axonal (CMT4C4) CMT. Common GDAP1 mutations are consquence of founder effect. Mutations in PRX (periaxin) gene are responsible for demyelinating CMT type (CMT4F). Approximately in a half of the CMT...
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Comparison of chemical composition of throughfall and deposited precipitation
Chaloupecký, Pavel ; Špičková, Jitka ; Fišák, Jaroslav ; Skřivan, Petr
Since June 2004 throughfall samples in beech and spruce vegetation have been taken at the observatory Milesovka. Ever since 1998 fog water samples have been taken there as well. In this paper are compared the concentrations of main ions and trace elements in throughfall and in deposited precipitation. The concentrations of main ions and trace elements in throughfal are primarily affected by the volume of samples. The highest concentrations of monitored sustances in throughfall were recorded in September and in October when the lowest rainfall totals were measured. The concentrations of monitored sustances were in throughfall mostly higher in spruce vegetation in comparison with beech vegetation. It is probably due to the thicker treetop in spruce vegetation on Milesovka observatory. Due to the thicker treetop a smaller volume of throughfall is let fall and the substances from ambient air are captured more effectively in comparison with beech vegetation. In the case of main ions the lowest concentrations were measured in fog water samples. For trace elements wasn´t data. From comparison with reference locality Lesni potok is obvious that concentrations of monitored sustances in throughfall on Milesovka exceed sharply concentrations in locality Lesni potok. This difference is considerably higher by spruce vegetation in comparison to beech vegetation which indicate that it is necessary take not only local air quality into account but also type of vegetation and thick of treetop which can very significantly contribute to the chemical composition of throughfall.
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Bimodal distributions
Došlá, Šárka ; Dupač, Václav (referee) ; Anděl, Jiří (advisor)
We study the bimodality of the mixture of two unimodal distributions. In the special cases we give necessary and su±cient conditions ensuring the bimodality of such mixtures. We study the probability of the event that the histogram of a random sample from unimodal distribution indicates two peaks. For some types of unimodal distributions it is possible to simplify this problem and we can study histograms of samples from uniform distribution instead. We show that for increasing number of observations the probability that histogram with N classes has two peaks tends to the probability that the random permutation of numbers 1;...;N is bimodal.
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