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Study of neurosteroid effect on the NMDA subtype of glutamate receptor.
Krausová, Barbora ; Vyklický, Ladislav (advisor) ; Bendová, Zdeňka (referee)
N-methyl-D-aspartate (NMDA) receptors are glutamatergic ionotropic receptors involved in excitatory synaptic transmission, synaptic plasticity and excitotoxicity. They are heteromeric complexes of GluN1 combined with GluN2A-D and/or GluN3A-B subunits that are activated by glutamate and glycine. Many allosteric modulators can influence the activity of these receptors including neurosteroids. Pregnanolone sulfáte (3α5βS) is an endogenous neurosteroid that inhibits NMDA receptors in a use-dependent manner and has neuroprotective effect. Binding site for 3α5βS on the NMDA receptor molecule is still not indentified. The aim of my work was to contribute to the identification of the biding site by kinetic analysis of rate of response return from 3α5βS inhibition. Using the point mutation we also attempted to identify the amino acids residues that could be involved in the neurosteroid binding. In order to study the effect of 3α5βS on NMDA receptors the electropfysiological recordings on human embryonic kidney 293T cells expressing recombinant GluN1/GluN2B receptors was performed. We confirm that the effect of 3α5βS on GluN1/GluN2B receptors is voltage-independent. The results of my work indicate that steroids can reach the binding site on the NMDA receptors through the membrane rather than directly from the aqueous...
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Receptors of NK cells
Hernychová, Lucie ; Novák, Petr (advisor) ; Pavlů, Barbora (referee)
NK cells play an important role as a part of the innate immune system, they however share many common features with cells of the adaptive immune system and they can modulate their functions as well. NK cells recognize non-self molecules (induced by viral infection or tumor transformation) through a wide variety of receptors on the cell surface. They also express receptors specific for their own structures, MHC glycoproteins. NK cells distinguish infected or transformed cells according to the quantity of these molecules on the target cell surface. Then NK cells allow apoptotic signals to cause cell death or the tolerance is established. They also promote inflammatory responses by the production of cytokines and chemokines. NK receptors can be grouped into activating, inhibitory, adhesion, cytokine, and chemokine receptors depending on their function. Based on interactions with appropriate ligands, NK cells exert cytotoxicity or they are inhibited. Moreover, their functions are influenced by the cytokine microenvironment. NK receptors can be also divided into C-type lectin and immunoglobulin superfamilies according to the structure. Ly49, NKG2/CD94 and NKR-P1 are receptor families that belong to the C-type lectin glycoproteins. These molecules have a type II transmembrane protein orientation and they...
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Inhibition of Thymidine Phosphorylase
Zákoucká, Eva ; Brynda, Jiří (advisor) ; Obšil, Tomáš (referee)
2. Abstract Thymidine phosphorylase (TPase), also known as gliostatin or Platelet-derived endothelial cell growth factor (PD-ECGF), is an enzyme with an important role in the nucleoside metabolism and is also involved in degradation and recycling of DNA. TPase catalyzes the reversible phosphorolysis of pyrimidine 2'-deoxynucleosides to 2-deoxy-D-ribose-1- phosphate and their respective bases, as well as the transfer of the deoxyribosyl moiety from one pyrimidine base to another. Thymidine phosphorylase is a therapeutic target of great importance because of its participation in angiogenesis especially in solid tumors of various tissues. Therefore, TPase stimulates tumor growth and progression, as well as metastasis. In addition to this, TPase inhibits apoptosis, particularly of tumor cells and causes degradation of several antiviral and anticancer drugs. Apart from the carcinoma tissues, thymidine phosphorylase is overexpressed in various other tissues affected by disorders characterized by proliferation of blood vessels including psoriasis, rheumatoid arthritis and atherosclerosis. Inhibiting the activity of TPase selectively in the tissues affected by the diseases listed above would be of great therapeutic significance. Therefore, many inhibitors, mainly substrate analogues, have been designed based on the...
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Antibacterial effect of plant oils containing medium-chain fatty acids
Laloučková, Klára ; Skřivanová, Eva (advisor) ; Rondevaldová, Johana (referee)
This diploma thesis focuses on antibacterial effect of plant oils containing medium-chain fatty acids (MCFA). The minimum inhibitory concentration (MIC) of eight chosen plant oils was defined as the mode of the lowest concentrations that were able to reduce the bacterial growth of 13 pathogenic and 6 beneficial intestinal strains of bacteria by 80 %. Coconut (Cocos nucifera), palm, red palm and palm kernel (Elaeis guineensis), Cuphea (C. lanceolata and C. ignea), babassu (Attalea speciosa, syn. Orbignya speciosa), tucuma (Astrocaryum vulgare), and muru-muru (Astrocaryum murumuru) oils were selected. Their antibacterial activity was tested towards following bacteria: Bifidobacterium animalis, B. longum, Campylobacter jejuni, Clostridium perfringens, Enterococcus cecorum, Escherichia coli, Lactobacillus acidophilus, L. fermentum, Listeria monocytogenes, Salmonella enteritidis, S. infantis, S. typhimurium and Staphylococcus aureus. To identify the fatty acids composition of tested oils a gas chromatography was used. Consequently, the MIC of each oil towards all the bacteria was determined by a broth-microdilution test in 96-well microtitration plates. The essentiality of cleavage of selected oils by lipase was observed, in order to activate their antibacterial effect. None of the tested oils exhibited any potential to inhibit the growth of Gramnegative bacterial strains even after cleavage. Furthermore palm and palm red oil did not exhibit any antibacterial action towards any of the tested bacterial strains. The strongest antibacterial activity was observed in tucuma oil, that inhibited C. perfringens by MIC=0.14 mg/ml. Other oils inhibited the growth of C. perfringens in concentrations from 0.25 to 4.5 mg/ml. The growth of E. cecorum was inhibited by coconut, babassu, Cuphea, palm kernel, muru-muru and tucuma oil in MIC range between 1.12 - 4.5 mg/ml. The only compound active against L. monocytogenes was Cuphea oil (MIC 1.12 mg/ml). Oils that were able to inhibit the growth of S. aureus strain showed MIC from 0.56 to 2.25 mg/ml (coconut, babassu, Cuphea, palm kernel, muru-muru and tucuma oil). Undetected susceptibility of B. animalis, B. longum, L. acidophilus and L. fermentum bacterial strains to tested oils was evaluated as a positive effect. According to the foregoing statements, it can be concluded that the plant oils containing MCFA show antibacterial effect towards Grampositive strains of bacteria after their cleavage by lipase. No showed influence to beneficial intestinal microflora can be a big advantage.
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The Influence of Temperature Fluctuation on the Efficiency of Deammonification Process During Wastewater Treatment
Fridrichová, Michala ; Švehla, Pavel (advisor) ; Vojtěch , Vojtěch (referee)
Deammonification is biological process, where ammonia is removed out of the wastewater. Advantages, compared to traditional nitrification/denitrification, consist in saving energy used to aeration and lower requirements to organic substrate. Anammox bacteria, which are realizing the process are very sensitive. Their optimal temperature is about 35 °C to 45 °C. In real life, the treatment of wastewater runs in lower temperature. This thesis is focused on the influence of temperature fluctuation on efficiency of deammonification.
For the experiment was used model with CSTR reactor, which deals with adjusted sludge water from anaerobic sludge stabilization. Sludge water from ÚČOV Praha was diluted by tap water and nitrite nitrogen was added. Anammox bacteria were cultivated in form of suspension (activated sludge), which was obtained in anammox reactor from estonian university in Tartu. The experiment lasted 280 days. It was divided into three phases, depending on changing temperature. In the first part, the average temperature was 23,3 °C, in the second part 27,5 °C, and in the third part was setted up the temperature decrease from 27 °C to 16,2 °C. The volume load of Ntotal was between 0,024 and 0,174 kg/(m3.d).
With increasing temperature was noticed increasing efficiency of N-amon and N-
NO2- removal. The hypothesis, that anammox rector can be succesfully operated in low temperature (18,3 °C), was confirmed. Inhibition caused by temperature was noticed under 16,2 °C. At this point, efficiency of removal N-amon, N-NO2-, N-NO3- and Ntotal decreased. Anammox bacteria approved ability to deal with short-term (1 week) temperature drop. After increase of temperature from 16,2 °C back to 23,9 °C, it was detected high ability to remove nitrogen forms. Average effectivity of Ntotal removal was 45,1 %. Higher efficiency was reached of N-amon, it was 72,0 %. During the experiment was removed 88,9 % N-NO2-. Because of the collected results, we can say, the annamox reactor can be sucessfully run in lower temperatures around 16,2 °C, if inhibition caused by temperature is short-term.
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Analysis of Thick Film Amperometrical Sensors Signal and Its Usage for Measurement and Characterization of Enzymes
Ondruch, Vít ; Kizek, René (referee) ; Masojídek,, Jiří (referee) ; Vrba, Radimír (advisor)
V práci je popsán princip synchronní detekce (SD), který byl uplatněn při měření s biosenzory. Metoda SD umožňuje dosažení výrazně lepšího poměru signálu k šumu, vyššího limitu detekce a celkové zlepšení robustnosti měření. Uplatnění SD při měření s biosenzory umožní zlepšit analýzu jeho odezvy a umožní odstranění nežádoucích interferencí nebo šumů, které mohou být způsobeny například mícháním roztoku, elektromagnetickými vlivy nebo parazitními proudy. SD také umožňuje rozložit získaný signál na odezvu stimulace a na dlouhodobý signál jiného procesu, a dále také identifikovat jevy druhého řádu. Pro identifikaci stimulačního signálu ve výstupním signálu měření byl na základě lineárního statistického modelu vyvinut specializovaný software. SD byla ověřena na modelovém případu výstupního signálu biosenzoru s aplikovaným komplexem fotosystému II (PSII) a jeho odezvě na stimulaci světlem. Odezva PSII se řídí kinetikou prvního řádu a může být také ovlivněna inhibitory. Kinetické konstanty vazby herbicidu na PSII závisí lineárně na koncentraci herbicidu. To umožňuje jejich měření také při nízkých koncentracích herbicidu.
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Inhibition of Hazardous Compounds in Alumino-Silicate Systems
Koplík, Jan ; Škvára, František (referee) ; Rovnaníková, Pavla (referee) ; Havlica, Jaromír (advisor)
The ability of alumino-silicate systems to immobilize hazardous compounds has been investigated since 1990s. The aim of this work is to develope alumino-silicate system (matrix) based on industrial waste products with ability to immobilize hazardous compounds (heavy metals). This ability of the matrix was confirmed by leaching tests based on the law 294/2005 Sb. Concentration of heavy metals in leachates was determined by ICP-MS method. Alumino-silicate system prepared in this work consists of high-temperature fly ash and blast furnace slag activated by mixture of alkaline activators (hydroxide and water glass). Matrixes were characterized by suitable analytic methods (XRD, SEM, FT-IR, DTA-TGA-EGA). The same analytic methods were used to describe the mechanism of immobilization of selected elements (Ba, Cu, Pb) in prepared systems.
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Inhibition of hydrogen evolution in aluminum-phosphate refractory binders
Bednárek, Jan ; Kalina, Lukáš (referee) ; Šoukal, František (advisor)
The thesis deals with the possibilities of inhibition of the reaction of aluminium-phosphate binders with wear iron, which is contained in bauxite. This material is mixed with phosphate binders to form refractories. The hydrogen is produced by this reaction causing the mixture foaming. The amount of evaluated hydrogen was observed by the measuring by the Jank’s calcimeter. Also the shape of oxidation-reduction potential of the binders was measured before and after mixing with aggregate, using potentiometer. The influence of the addition of various cations on the hydrogen evolution and on the oxidation-reduction potential was observed. The effectiveness of the inhibitors was studied also visually by forming test elements.
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Komplementární metody k použití oxidu siřičitého
Malík, Marek
This thesis was focused to finding chemicals an other methods that are able to reduce or replace the dose of sulfur dioxide in the wine industry. Introductory chapters deal with sulfur dioxide - its specific characteristics and forms which can be used in wine practice and way of its particular application. It was also processed a large number of literary resources with different complementary methods and provide an overview. Methods, described in this thesis, have been previously tested and they had some potential in reducing sulfur dioxide doses during the production of wine. Thesis mainly describes the interesting physical methods but the most important part of this thesis is description of chemicals with different properties and structures. The main essence of this work was experiment which studied two chemicals to reduce the doses of SO2 -- dimethyldicarbonate and higher fatty acids. The actual experiment was based on the inhibition of the four tested microorganisms in fermenting must of variety 'Marlen' and in saline (only in the case of Brettanomyces bruxellensis). Its output was counting the colonies grown on Petri dishes followed by consequential graphical demonstration of the sensitivity these microorganisms to dimethyldicarbonate and higher fatty acids.
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Bolesti zad jako civilizační onemocnění z pohledu fyzioterapie
KREJČOVÁ, Miluše
This work tell about problems with back pain and informations of patients. Look at the treraphy process and physiotherapist ´s effect with theraphy movement body and work with people mention then they can come to know what is right and what is wrong moving of ordinary day for their movement system. The main destination is preventation of the back pain. Know the right and wrong movement and movement´s habit is main of the preventation of the back pain and the best preventationly precaution is keeping this. Know of theory is mainstay of good therapy. The main destination of this work is getting better and describe to during and a cause the rise of back pain. The destinations were determine with help qualitative research presentation in this work.
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