| |
|
Complexes of Cationic Porphyrins with Nucleic Acids Studied by Surface Enhanced Resonance Raman Spectroscopy
Lásková, Barbora ; Mojzeš, Peter (advisor) ; Michl, Martin (referee)
Complexes of cationic porphyrins with nucleic acids are interesting from the point of view of delivery of therapeutic oligonucleotides into cells as well as for photodynamic therapy of cancer. Diploma thesis deals with study of the complexes of cationic metalloporphyrin CuTMPyP4 with poly(dG-dC)2, where intercalation of porphyrin within polynucleotide's base pairs is supposed and with poly(dA-dT)2, poly(dA)·poly(dT), in which external groove-binding of CuTMPyP4 on the helix is assumed. The measurements were made by SERRS, RRS and absorption spectroscopies. From the time evolution of the SERRS spectra for each complex it was found, that intensity of SERRS spectra and rate of SERRS kinetics for complexes fall short of intuitive supposition about low SERRS signal and its slow increasing in the case of intercalation of porphyrin, because for complex of CuTMPyP4 with poly(dG-dC)2, the SERRS kinetic are very fast and final SERRS signal is more intense than for poly(dA-dT)2, poly(dA)·poly(dT). Comparing the SERRS and RRS spectra of the complexes it was found that SERRS spectra correspond to the porphyrin molecules released from the complexes rather that to the entire complexes. Study of various colloidal systems used for SERRS measurements revealed that SERRS signal evolves with time of exposition, namely for...
|
|
Dynamics of mouse sperm capacitation and acrosome reaction
Dvořáková-Hortová, Kateřina ; Frolíková, Michaela ; Děd, Lukáš ; Šebková, Nataša
Capacitation followed by the acrosome reaction (AR), is a very complex event of molecular changes, including acrosome matrix rearrangement and actin polymerization, which mammalian sperm must undergo in the female reproductive tract in order to obtain the ability to penetrate and fertilize the egg. CD46 and β1-integrin belong to specific proteins, which are predicted to interact during molecular reorganization of capacitating sperm. The IZUMO1 as the primary fusion protein of the mammalian sperm is also involved in this dynamic network. We investigated the relationship between the Izumo, CD46 and β1 integrin relocation in the sperm head during the capacitation and AR in vitro. We have already successfully monitored by immunofluorescent labelling the dynamics of proteins CD46 and β1-integrin. The changes in the localization of these proteins associated with the AR and their mutual co-localization was observed. The original β1-integrin location in the freshly released epididymal sperm is in the acrosome and it relocates during the AR further through the sperm head compartments into the equatorial segment and over the whole sperm head. Its density over the equatorial segment is decreasing with the extended time of the AR. Also its presence in the perforatorium of the mouse sperm head is very prominent. The pattern for protein CD46 is extremely similar if not identical in both aspects such as compartment localization and time progress during capacitation and AR in vitro. The molecular interaction of CD46 and β1-integrin was investigated using the Proximity Ligation Assay and Super resolution microscopy STED. The data were statistically analysed. The newly obtained results from CD46 and β1-integrin relocation are in correlation with IZUMO1 dynamics and giving a substantial knowledge on the studied protein network rearrangement during capacitation and AR in mouse spermatozoa.
|
|
Giuseppe Verdi : Otello : Prague and Pilsen production
Karásek, Jan ; Kusnjer, Ivan (advisor) ; Hajóssyová, Magdaléna (referee)
The last opera but one by Giuseppe Verdi, Otello, does not belong to often performed ones in the Czech Republic. Despite this fact there were several successful production of Otello in the last years. To these good ones belong Pilsen production ( The Josef Kajetán Tyl Theatre, 2007) a Prague production ( Prage State Opera 2009). In Otello, Verdi´s masterpiece (premiere 1987 in La Scala, Milan), the composer applied new approach.Contrary to former numbered scenes he created complex interweaving of all opera components. As a theme served Shakespeare´s tragedy that remains actual even after four hundred years. Yet Verdi and his librettist Arrigo Boito changed the story a bit - or adapted it to the opera scenes to be more precise. All this was successfully capitalized by directors of both above mentioned productions Ladislav Štros in Pilsen and Lubor Cukr in Prague.Prague production, which was a renewed production of the successful one from 1991, was distinguished by a brief, pure scene, which catalyzed the characters and the singer´s performace. Even though the performace or the singers in Pilsen production was not always meeting the Prague standards, the scene was richer and the stylization fitted the director´s intentions. Both productions were well appreciated both by experts and by the audience. The fact they were performed for several years can serve as a proof.
|
| |
| |
|
Possibility of using VIS - NIR spectroscopy for predicting the properties of forest soils
Kratina, Josef ; Borůvka, Luboš (advisor) ; Lucie, Lucie (referee)
The aim of this PhD thesis was an objective assessment of application of VNIR spectroscopy for predicting properties of forest soils. For each soil property were found the most appropriate combination of statistical methods for pre-processing (continuum removal, 1. derivation, 2. derivation) and processing (PLSR, PCR, SVM) of certain spectral bands. As generally successful shows a combination of methods 1. derivation and support vector machine throughout the VNIR spectral range (400-2500 nm). In some cases, however, they proved to other models. Among the best predictable features include pH, content of oxidizable carbon, aluminum, iron, silicon, or calcium (at higher concentrations). Not very high success rate prediction was found in indicators that take low values (sodium, manganese, aluminum or ferrous complexes). The results show that VNIR spectroscopy method is applicable for predicting properties of forest soils. It can not completely replace traditional analysis, but it can very well complement, especially in practice. For example, when the soil mapping can help thicken network data and refine the information better than other methods of spatial estimation. It is applicable in cases where it is required large amounts of data in a short timeframe and at minimal cost. It is suitable for monitoring trends over time, or for a quick survey of an area.
|
|
The importance of vitamin D and calcium in the human diet
Bártová, Magdaléna ; Hejtmánková, Alena (advisor) ; Michlová, Tereza (referee)
Vitamin D refers to a group of fat soluble steroids. The most important forms are
cholecalciferol occurring in foods of the animal origin and ergocalciferol of the plant origin. Human
accept them in the diet; the fatty fishes, fish liver, and some other foods like milk, eggs or yeasts are
rich resources of vitamin D. Unlike the other vitamins, the synthesis of vitamin D can also take place
in the living body. Cholecalciferol is formed in the skin from its precursor 7 - dehydrocholesterol by
the effect of UVB radiation. The conversion efficiency depends on various factors.
Two successive reaction steps are necessary for the activation of vitamin D. The first step of
hydroxylation occurs in the liver to be formed calcidiol. Calcidiol is the principal form of vitamin D in
the blood acting also as the indicator of body supplies. The second one takes place in the kidneys
where calcidiol is transformed to calcitriol. Calcitriol is assumed as the active hormonal form of
vitamin D binding to the receptor for vitamin D - VDR. The best known and the most explored
function is the effect of vitamin D on the calcium and phosphorus homeostasis. Consequently, vitamin
D also influences the proper functions of muscles and the immune system. It reduces the risk of the
cancer and cardiovascular diseases by various mechanisms as well. However, there are assumed
another effects of vitamin D on the human body, which are not fully yet understood and are the subject
for further research.
Calcium constitutes the major mineral component of bones and teeth. It is an essential nutrient
and therefore it is necessary to supply it with food. Its content in foods is various as well as its
usability from these. The major resources of calcium are milk and dairy products. Calcium is also
present in eggs, mineral waters, certain fishes and food of plant origin. Especially, the plant resources
usability of calcium is limited because of the insolubility of some calcium complexes. Calcium is
essential for the composition structure of bones and teeth. Besides of structural function, it has a main
role in the blood coagulation, neuromuscular transmission or muscle contraction.
Vitamin D has an influence on the usability of calcium because of the efficiency increase of
calcium absorption in the intestine. The lack of both micronutrients leads to skeletal diseases -
osteoporosis, osteomalacia and rickets. The adequate intake of both essential part of food, vitamin D
and calcium, is important especially for the growing children, elderly people, and pregnant and
lactating women.
|
|
Molecular dynamics simulations of complexes consisting of proteins and nucleic acids
Hammer, Jiří ; Barvík, Ivan (advisor) ; Obšil, Tomáš (referee)
The goal of this diploma thesis was to study interactions of Argonaute (Ago) protein in a complex with nucleic acids. Based on the available crystal structures of full length Argonaute (from A. aeolicus, Aa-Ago) and/or its domains (human PAZ domain, Hs-PAZ), twelve different simulations were computed. Two initial simulations used model of Aa-Ago with either a duplex of DNA/RNA or RNA/RNA. Major difference was in behavior of the PAZ domain (especially its arginine residues), which tolerated the guide DNA in one simulation, but was disturbing the RNA guide strand in the second. Such an interaction could serve as a mechanism of the substrate recognition. In additional simulations (3-9) employing the Hs-PAZ domain, where no disturbance was found in the DNA/RNA hetero-duplex. Different arrangements of the active site geometry as well as empirical parameterizations of Mg2+ ion were probed and analyzed. The DD-catalytic motif plus D683 in Aa-Ago (equivalent to H807 in human Argonaute2) was observed to coordinate the Mg2+ ion in one and two metal ion dependent catalysis models. Highly conserved R570 and E578 created mutual hydrogen bonds and hence stabilized the active site. To make the cleavage irreversible, a role for the first (unpaired) nucleotide from 5'-end of the guide strand was suggested. It lies in a...
|
|
Effect of Camellia sp. on dairy matrix digestion
Scholzová, Tereza ; Potůčková, Miroslava (advisor) ; Vladimír, Vladimír (referee)
The aim of this bachelor thesis is to summarise of current knowledge about the effects and biological properties of the substances contained in leaves of Camellia sinensis, their digestion and their effect on the digestion of dairy matrices. Camellia sinensis is a plant, which is used to tea production. Tea is manufactured by fermentation of tea leaves and according to its degree it is possible to prepare different kinds of this product. The best known are green, black and oolong tea. Beverages prepared from tea leaves contain many bioactive compounds, including alkaloids, free amino acids, proteins and vitamins. However, the most important are polyphenolic substances flavonoids, which are also the major bioactive constituents of tea. These compounds have many pharmacological properties such as antiatherosclerotic, antibacterial, anticancer, antiviral, hypolipidemic and hypocholesterolemic.
The effect of milk on the biological activity of tea polyphenols has been a subject of many studies but the mechanism by which the antioxidant activity of this compounds affect milk and dairy products and especially their digestion process has not been fully understood yet. It was found that flavonoids can interact with proteins rich in prolin, including also casein, via covalent and noncovalent interactions, especially by hydrophobic interactions and hydrogen bonds. The resulting complexes may destabilize protein molecules and cause their precipitation, thereby their digestibility is improved. On the contrary, stable complexes protect polyphenols from autooxidation. Interesting is also crosslinking effect of green tea flavonoids on milk proteins. These substances also have the ability to form complexes with lipids and lipolytic enzymes and so decrease lipids digestion and absorption, including the milk fat and its accompanying components such as cholesterol. It was also observed reduced absorption of other fat-soluble substances like persistent organic compounds.
|
guest ::
