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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Analýza rentgenových difraktogramů organických krystalických látek / Analysis of x-ray diphractograms of organic crystalline solids

Stejkora, Jakub January 2011 (has links)
Derivates of diketopyrrolopyrrole are colored pigments with potential use in field of organic semiconductor structures. Their electrical attributes such as conductivity, photocon¬¬ductivity and electroluminescence relate to their crystal structures that determine charge transport path through the compound. For crystallographic structure determination from RTG diffractometry it is needed to grow a measurable single crystal. Growing crystals of derivates of diketopyrrolopyrrols is very difficult due to their poor solubility in all solvents. Several relatively suitable – perhaps even measurable – samples were obtained throughout the testing of series of methods. One of these samples was measured with RTG diffractometry and on the ground of this measurement it was possible to find and solve the crystallographic structure.
2

Vliv farmak ze skupiny SYSADOA na osteoartrozu kolenního kloubu / Influence of drugs from the group SYSASOA for knee osteoarthrosis

Milerová, Klára January 2015 (has links)
Tittle:Influence of drugs from the group SYSADOA for knee osteoarthrosis Objectives:The aim of the thesis is to evaluate the effect of three months use of drugs from the group SASADOA on subjective perception of the difficulties associated with knee osteoarthritis and to determine the intensity of gonarthrosis progression in connection with knee cartilage width. Methods:For the study18 probands were obtained from rehabilitation and orthopedic institutions in Prague. The criterion for recruitmen t was knee joint osteoarthrosis of II. degree. For all participants there was conducted input kinesiology analysis and clinical examination, patient's medical history and filled in WOMAC questionnaire. All participants were sent for an X-ray of the knee. Group of probands was randomly divided into two groups. An experimental group was taking Proenzi 3 plus, a control group was taking placebo. Both groups were taking medications for 12 weeks. After this time the probands arrived to check- up and second filling in of the WOMAC questionnaire. The experimental group that had been taking Proenzi 3 plus received placebo for additional 12 weeks, the control group received Proenzi 3 Plus. After finishing preparations all probands were invited to the last visit where they underwent follow-up examination, the third...
3

Sinalização retrógrada RTG-dependente controla a atividade mitocondrial e resistência a estresse em Saccharomyces cerevisiae / RTG-dependent retrograde signaling controls mitochondrial activity and stress resistance in Saccharomyces cerevisiae.

Torelli, Nicole Quesada 12 December 2014 (has links)
A sinalização retrógrada mitocondrial é uma via de comunicação entre a mitocôndria e o núcleo que regula a expressão de uma série de genes nucleares que codificam proteínas mitocondriais, em resposta a disfunções mitocondriais. Em Saccharomyces cerevisiae, a via depende de Rtg1p e Rtg3p, que juntos formam o fator de transcrição que regula a expressão gênica, e de Rtg2p, um ativador da via. Aqui, nós mostramos novos estudos direcionados à investigação do impacto da sinalização retrógrada RTG-dependente na fisiologia mitocondrial. Verificamos que mutantes incapazes de realizar sinalização retrógrada RTG-dependente apresentam consumo de oxigênio mais elevado e menor produção de peróxido de hidrogênio em fase estacionária quando comparados a células selvagens. Interessantemente, mutantes RTG são menos capazes de decompor peróxido de hidrogênio assim como manter-se viáveis quando desafiados com peróxido. Nossos resultados indicam que a sinalização por RTG está envolvida na indução hormética de defesas antioxidantes e de resistência a estresse, função ainda não descrita para este sistema. / Mitochondrial retrograde signaling is a communication pathway between the mitochondrion and the nucleus which regulates the expression of a subset of nuclear genes that codify mitochondrial proteins, mediating cell response to mitochondrial dysfunction. In Saccharomyces cerevisiae, the pathway depends on Rtg1p and Rtg3p, which together form the transcription factor that regulates gene expression, and Rtg2p, an activator of the pathway. Here, we provide novel studies aimed at assessing the functional impact of the lack of RTG-dependent signaling on mitochondrial activity. We show that mutants defective in RTG-dependent retrograde signaling present higher oxygen consumption and reduced hydrogen peroxide release in the stationary phase when compared to wild type cells. Interestingly, RTG mutants are less able to decompose hydrogen peroxide as well as maintain viability when challenged with hydrogen peroxide. Overall, our results indicate that RTG signaling is involved in the hormetic induction of antioxidant defenses and stress resistance, a function of this system not yet described.
4

Sinalização retrógrada RTG-dependente controla a atividade mitocondrial e resistência a estresse em Saccharomyces cerevisiae / RTG-dependent retrograde signaling controls mitochondrial activity and stress resistance in Saccharomyces cerevisiae.

Nicole Quesada Torelli 12 December 2014 (has links)
A sinalização retrógrada mitocondrial é uma via de comunicação entre a mitocôndria e o núcleo que regula a expressão de uma série de genes nucleares que codificam proteínas mitocondriais, em resposta a disfunções mitocondriais. Em Saccharomyces cerevisiae, a via depende de Rtg1p e Rtg3p, que juntos formam o fator de transcrição que regula a expressão gênica, e de Rtg2p, um ativador da via. Aqui, nós mostramos novos estudos direcionados à investigação do impacto da sinalização retrógrada RTG-dependente na fisiologia mitocondrial. Verificamos que mutantes incapazes de realizar sinalização retrógrada RTG-dependente apresentam consumo de oxigênio mais elevado e menor produção de peróxido de hidrogênio em fase estacionária quando comparados a células selvagens. Interessantemente, mutantes RTG são menos capazes de decompor peróxido de hidrogênio assim como manter-se viáveis quando desafiados com peróxido. Nossos resultados indicam que a sinalização por RTG está envolvida na indução hormética de defesas antioxidantes e de resistência a estresse, função ainda não descrita para este sistema. / Mitochondrial retrograde signaling is a communication pathway between the mitochondrion and the nucleus which regulates the expression of a subset of nuclear genes that codify mitochondrial proteins, mediating cell response to mitochondrial dysfunction. In Saccharomyces cerevisiae, the pathway depends on Rtg1p and Rtg3p, which together form the transcription factor that regulates gene expression, and Rtg2p, an activator of the pathway. Here, we provide novel studies aimed at assessing the functional impact of the lack of RTG-dependent signaling on mitochondrial activity. We show that mutants defective in RTG-dependent retrograde signaling present higher oxygen consumption and reduced hydrogen peroxide release in the stationary phase when compared to wild type cells. Interestingly, RTG mutants are less able to decompose hydrogen peroxide as well as maintain viability when challenged with hydrogen peroxide. Overall, our results indicate that RTG signaling is involved in the hormetic induction of antioxidant defenses and stress resistance, a function of this system not yet described.
5

Mikrostruktura a vlastnosti tenkých vrstev multiferroických komplexních oxidů připravených pomocí metody pulzní laserové depozice / Microstructure and properties of multiferroic complex oxide thin films prepared by pulsed laser deposition method

Machovec, Petr January 2021 (has links)
Title: Microstructure and properties of multiferroic complex oxide thin films prepared by pulsed laser deposition method Author: Petr Machovec Department: Department of Condensed Matter Physics Supervisor: RNDr. Milan Dopita, Ph.D., Department of Condensed Matter Physics Abstract: In the frame of this thesis, structure, microstructure, and real structure of multiferroic epitaxial layers of LuFeO3 were studied by means of X-ray reflectivity and X-ray diffraction. In theoretical part the theory of X-ray scattering on crystalline layers is described. Standard description of X-ray reflectivity on series of rough layers is presented. Moreover, a model of X-ray scattering on mosaic layer is described. For experimental part of the work three samples were prepared by pulsed laser deposition method. First sample on sapphire substrate (Al2O3), second on platinum layer deposited on sapphire substrate and third on yttrium stabilized zirconia substrate. From the X-ray reflectivity curves the parameters such as layer thickness, interface roughness, surface roughness and material density, were determined. By analysing measured reciprocal space maps, lattice parameters and mosaic model parameters, such as mean mosaic block size, mosaic block size distribution, mosaic block misorientation and residual microstrain, were...
6

Desenvolvimento de membransas de gelatina/quitosana e o estudo do processo de reticulação / Development of chitosan/gelatin membranes and the study of crosslinking process

Oliveira, Ana Paula Ramos de 04 October 2013 (has links)
A formação do biofilme nas áreas subgengivais pode levar a respostas vasculares e celulares, as quais podem resultar na doença periodontal, portanto, periodontite crônica são a inflamação crônica e progressiva, caracterizada clinicamente por inflamação gengival, sangramento à sondagem, diminuição da resistência dos tecidos periodontais à sondagem, perda de inserção gengival e osso alveolar. Em estudos de lesões que ocorrem no processo alveolar, é observado que estas muitas vezes cicatrizam com o tecido fibroso, em vez do tecido ósseo. A regeneração tecidual guiada (RTG) é um dos tratamentos para reconstituição de novo tecido, o qual utiliza membranas como barreira de proteção física da área defeituosa. Esta barreira previne a invasão de outros tecidos e permite repovoamento seletivo da superfície da raiz pelas células do ligamento periodontal e osso alveolar, capazes de promover a regeneração de tecidos de suporte perdidos como resultado de uma doença periodontal progressiva. Neste contexto, vários tipos de barreiras físicas têm sido sugeridos para uso em RTG e, as membranas biodegradáveis são de grande interesse, devido a essas evitarem o segundo procedimento cirúrgico para remoção da barreira. Assim, no presente estudo membranas de quitosana/gelatina com e sem glicerina foram desenvolvidas e o efeito do agente reticulante (glutaraldeído - GTA) foi analisado por dois métodos: imersão e vapor. O intumescimento das membranas foi realizada in vitro em tampão fosfato a 36°C e as membranas foram caracterizados por espectroscopia no infravermelho (FTIR). No espectro de FTIR obtido a partir das membranas de quitosana/gelatina as bandas características de ambos os polímeros foram observados, indicando que houve interação entre a quitosana e a gelatina. Nos espectros obtidos a partir de membranas reticuladas, foi observado um deslocamento da banda a 1654 cm-1, sugerindo efeitos do GTA. Nos resultados do ensaio de intumescimento foram observados que no início do processo a absorção de massa ocorreu rapidamente, atingindo o equilíbrio em 15 minutos. Observou-se também que para as membranas de quitosana/gelatina a taxa de intumescimento diminui com o aumento da concentração de GTA e isso foi mais pronunciado para as membranas sem glicerina (em ambos os métodos de reticulação). Ademais foi observado que o método de reticulação por imersão confere as membranas menor grau de intumescimento, quando comparada com os resultados obtidos através da reticulação por vapor. Entretanto, as membranas reticuladas por vapor são mais resistentes à fragmentação, mostrando-se superiores no ponto de vista morfológico, podendo apresentar melhor estabilidade biológica. Dentre as condições estudadas, as membranas de quitosana/gelatina/glicerina reticuladas por vapor apresentaram características como flexibilidade e facilidade de manuseio, sugerindo que estas membranas podem apresentar boas características para uso em RTG. / The biofilm buildup within the sub gingival areas can lead to vascular and cellular responses, which can result in periodontal disease. Chronic periodontitis are chronic inflammation and progressive, clinically characterized by gingival inflammation, bleeding on probing, decreased resistance of the periodontal tissues on probing, gingival attachment loss and alveolar bone. In studies of lesions occurring in the alveolar process, it is observed that these often heal with fibrous tissue rather than bone. The guided tissue regeneration (GTR) is one of the treatments to replenish new tissue using a membrane as a barrier of physical protection of the defective area by preventing the invasion of other tissues and allowing repopulation selective root surface by cells of the periodontal ligament and alveolar bone, capable of promoting the regeneration of supporting tissues lost as a result of progressive periodontal disease. In this context, various types of physical barriers have been suggested for use in GTR and the biodegradable membranes are of great interest, due to avoid second surgical procedure for removal the barrier. Thus, in this study, chitosan/gelatin membranes, with and without glycerin were developed and the effect of cross-linked (glutaraldehyde) was analyzed by two methods: immersion and vapour. The swelling of these membranes was performed in vitro in saline at 36°C and the membranes were characterized by FTIR spectroscopy. In the FTIR spectrum obtained from chitosan/gelatin membrane bands features of both polymers were observed, indicating interaction between chitosan and gelatin. In the spectra obtained from membranes crosslinked, was observed a shift of the band at 1409 cm-1 to 1380 cm-1 associated with angular deformations of C-H, suggesting effect of glutaraldehyde. In the curves of swelling were observed that at the beginning the process of mass absorption occurred rapidly, reaching equilibrium in approximately 15 minutes. It was also observed that for chitosan/gelatin membranes the percentage of swelling decreases with increasing concentration of glutaraldehyde and this was more pronounced for membranes without glycerin (for both crosslinked methods). In addition it was noted that the immersion method immersion gives a lower degree of swelling, when compared with the results obtained by vapour crosslinking. However, vapour crosslinked membranes are more resistant to fragmentation, showing up higher in the morphological point of view, and may have better biological stability. Furthermore the membranes chitosan/gelatin/glycerin vapour crosslinked are flexible and ease of handling, suggesting that these these membranes have good characteristics for use in GTR.
7

Odhad průměrné radiační zátěže při lékařském diagnostickém ozáření / Assessment of the average radiation exposure from medical diagnostics

BALTA, Petr January 2016 (has links)
The diploma thesis dealt with the theme of "Assessment of the average radiation exposure from medical diagnostics" is divided into two main parts. The first one is concerned with the various measurement of radiation dose during diagnostic medical radiation. The second one is focused on radiation dose optimization during diagnostic medical radiation. With increasing of the collective effective dose in population, we should consider the importance of radiation protection during diagnostic medical radiation and accuracy of effective dose estimate that is used during individual medical examinations. On the basis of these estimates, it is necessary to determine the medical theory of radiation protection and to gain control over radiation dose and optimization of diagnostic medical radiation somehow. The theoretical part describes the kinds of ionizing radiation and their biological effects on organism. This part follows the chapter devoted to radiation protection and legal framework of the Czech Republic that is related to the topic: the application of ionizing radiation, mainly the Act No. 18 /1997 Coll. on Peaceful Utilisation of Nuclear Energy and Decree of the SÚJB No. 307 /2002 Coll., on Radiation Protection. There are discussed also the particular principles of protection against radiation. Afterwards, in the theoretical part, the quantities and the units used by radiodiagnostics and nuclear medicine are described. They are needed to know for the following determination and the estimate of dose amount absorbed by human organism. The conclusion of the theoretical part treats the methods used for estimate of dose received during medical examination and new trends in radiation management of individual patients. In the diploma thesis, there are set up two research questions. The thesis has been looking for the answers by its own research. The first research question is, if the current way of measurement of radiation dose is sufficient. The second one has been asking for manners of access allowed the decreasing of dose for patients regarding to registered effective dose. On the basis of these defined research questions, the basic aims have been set up to consider the application of individual methods of dose evaluation during medical radiation, to determine, from the registered values, probably the most exact method for evaluation of radiation dose and to deduce the probability of stochastic effects formation conditioned by radiation. The research was performed with two groups of patients that were undergone skiagraphic examination of lungs and examination of stomach by computed tomography (CT). The research devoted to skiagraphic examination of lungs was dealt with women suffering by similar body constitution. The results of measured effective dose of these patients were compared, and the manner of measurement and influencing of final absorb dose in the mammary gland were presented. The relation of individual projections towards probability of cancer birth conditioned by radiation was demonstrated. For comparison and setting up the most exact method, the first group was measured by the most available and the most common way used in clinical practice. PCXMC and ImPACT CT software are the most applying methods in clinical practice. As the most available method, standardize values and the procedure from the Bulletin of the Ministry of Health for Radiation Physics were applied. The final effective doses were compared with the local and national diagnostic referential levels in order to set up the correct procedure of radiation protection. The second researched group of patients undergone stomach examination performed by computed tomography (CT). The final effective doses of these patients were compared according to ICRP 60 and ICRP 103. Just as in the first group, there were compared two methods of measurement, the most available and the most applying in the practice.
8

Desenvolvimento de membransas de gelatina/quitosana e o estudo do processo de reticulação / Development of chitosan/gelatin membranes and the study of crosslinking process

Ana Paula Ramos de Oliveira 04 October 2013 (has links)
A formação do biofilme nas áreas subgengivais pode levar a respostas vasculares e celulares, as quais podem resultar na doença periodontal, portanto, periodontite crônica são a inflamação crônica e progressiva, caracterizada clinicamente por inflamação gengival, sangramento à sondagem, diminuição da resistência dos tecidos periodontais à sondagem, perda de inserção gengival e osso alveolar. Em estudos de lesões que ocorrem no processo alveolar, é observado que estas muitas vezes cicatrizam com o tecido fibroso, em vez do tecido ósseo. A regeneração tecidual guiada (RTG) é um dos tratamentos para reconstituição de novo tecido, o qual utiliza membranas como barreira de proteção física da área defeituosa. Esta barreira previne a invasão de outros tecidos e permite repovoamento seletivo da superfície da raiz pelas células do ligamento periodontal e osso alveolar, capazes de promover a regeneração de tecidos de suporte perdidos como resultado de uma doença periodontal progressiva. Neste contexto, vários tipos de barreiras físicas têm sido sugeridos para uso em RTG e, as membranas biodegradáveis são de grande interesse, devido a essas evitarem o segundo procedimento cirúrgico para remoção da barreira. Assim, no presente estudo membranas de quitosana/gelatina com e sem glicerina foram desenvolvidas e o efeito do agente reticulante (glutaraldeído - GTA) foi analisado por dois métodos: imersão e vapor. O intumescimento das membranas foi realizada in vitro em tampão fosfato a 36°C e as membranas foram caracterizados por espectroscopia no infravermelho (FTIR). No espectro de FTIR obtido a partir das membranas de quitosana/gelatina as bandas características de ambos os polímeros foram observados, indicando que houve interação entre a quitosana e a gelatina. Nos espectros obtidos a partir de membranas reticuladas, foi observado um deslocamento da banda a 1654 cm-1, sugerindo efeitos do GTA. Nos resultados do ensaio de intumescimento foram observados que no início do processo a absorção de massa ocorreu rapidamente, atingindo o equilíbrio em 15 minutos. Observou-se também que para as membranas de quitosana/gelatina a taxa de intumescimento diminui com o aumento da concentração de GTA e isso foi mais pronunciado para as membranas sem glicerina (em ambos os métodos de reticulação). Ademais foi observado que o método de reticulação por imersão confere as membranas menor grau de intumescimento, quando comparada com os resultados obtidos através da reticulação por vapor. Entretanto, as membranas reticuladas por vapor são mais resistentes à fragmentação, mostrando-se superiores no ponto de vista morfológico, podendo apresentar melhor estabilidade biológica. Dentre as condições estudadas, as membranas de quitosana/gelatina/glicerina reticuladas por vapor apresentaram características como flexibilidade e facilidade de manuseio, sugerindo que estas membranas podem apresentar boas características para uso em RTG. / The biofilm buildup within the sub gingival areas can lead to vascular and cellular responses, which can result in periodontal disease. Chronic periodontitis are chronic inflammation and progressive, clinically characterized by gingival inflammation, bleeding on probing, decreased resistance of the periodontal tissues on probing, gingival attachment loss and alveolar bone. In studies of lesions occurring in the alveolar process, it is observed that these often heal with fibrous tissue rather than bone. The guided tissue regeneration (GTR) is one of the treatments to replenish new tissue using a membrane as a barrier of physical protection of the defective area by preventing the invasion of other tissues and allowing repopulation selective root surface by cells of the periodontal ligament and alveolar bone, capable of promoting the regeneration of supporting tissues lost as a result of progressive periodontal disease. In this context, various types of physical barriers have been suggested for use in GTR and the biodegradable membranes are of great interest, due to avoid second surgical procedure for removal the barrier. Thus, in this study, chitosan/gelatin membranes, with and without glycerin were developed and the effect of cross-linked (glutaraldehyde) was analyzed by two methods: immersion and vapour. The swelling of these membranes was performed in vitro in saline at 36°C and the membranes were characterized by FTIR spectroscopy. In the FTIR spectrum obtained from chitosan/gelatin membrane bands features of both polymers were observed, indicating interaction between chitosan and gelatin. In the spectra obtained from membranes crosslinked, was observed a shift of the band at 1409 cm-1 to 1380 cm-1 associated with angular deformations of C-H, suggesting effect of glutaraldehyde. In the curves of swelling were observed that at the beginning the process of mass absorption occurred rapidly, reaching equilibrium in approximately 15 minutes. It was also observed that for chitosan/gelatin membranes the percentage of swelling decreases with increasing concentration of glutaraldehyde and this was more pronounced for membranes without glycerin (for both crosslinked methods). In addition it was noted that the immersion method immersion gives a lower degree of swelling, when compared with the results obtained by vapour crosslinking. However, vapour crosslinked membranes are more resistant to fragmentation, showing up higher in the morphological point of view, and may have better biological stability. Furthermore the membranes chitosan/gelatin/glycerin vapour crosslinked are flexible and ease of handling, suggesting that these these membranes have good characteristics for use in GTR.
9

Optimalizace modelu kožní bariéry s obsahem ceramidů izolovaných z lidského stratum corneum / Optimization of the skin barrier model with isolated ceramides of human stratum corneum

Dulanská, Lucia January 2021 (has links)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Author: Lucia Dulanská Supervisor: Mgr. Petra Pullmannová, Ph.D Title of thesis: Optimization of the skin barrier model with isolated ceramides of human Stratum corneum Stratum corneum (SC), the uppermost layer of the skin, regulates transcutaneous water loss and protects against outer conditions and harmful substances. It consists of cornified cells - corneocytes and extracellular lipid matrix, which is responsible for the barrier functions. Corneocytes are covered with covalently bound lipids creating the corneocyte lipid envelope (CLE). CLE is considered to interconnect the extracellular lipids with corneocytes and to have a templating effect. We aimed to optimize a skin lipid model simulating also the presence of CLE. The lipidic part of the model was prepared from an equimolar mixture of isolated human skin ceramides (hCer), cholesterol and free fatty acids (FFA, either protonated or deuterated) with 5 weight % of cholesteryl sulfate. hCer were extracted from the isolated human SC and purified by the column chromatography. The composition of hCer was determined by the high- performance thin-layer chromatography. The reverse-phase and normal phase silica gel particles served as the CLE...
10

Diferenciace kvasinkových kolonií: Role vybraných transkripčních faktorů a metabolických proteinů / Differentiation of yeast colonies: The role of selected transcription factors and metabolic proteins

Plocek, Vítězslav January 2021 (has links)
5 Abstract Although yeasts are unicellular microorganisms, they form complex multicellular formations such as biofilms and colonies under natural conditions. Within these structures, processes such as cell differentiation, specialization by particular cell populations and cell signalling, which are typical of multicellular organisms, take place. The literature introduction to this thesis summarizes current knowledge regarding the development of biofilms and colonies, in particular those of the model organism, Saccharomyces cerevisiae, and some selected regulations that are important for the formation of multicellular structures. In the results section, I focus on two lines of research. The first is directed towards mechanisms, involved in the formation of multicellular structures. In studying the formation of SLI biofilms (biofilms at the solid/liquid interface), we have documented the antagonistic role of the regulators CYC8 and TUP1 in their formation and have also described the effect of the presence of glucose on the development and stability of SLI biofilms of strain BR-F. During this study we[D1] have developed an imaging method that allows us to prepare and observe the internal structure (vertical cross-section) of SLI biofilms, as well as the growth of unattached cells, under physiological...

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