Dissertations / Theses on the topic 'Mikrosomy'

This master thesis deals with the use of microfluidics for the purpose of microfluidic enzymatic reactor for drug screening. At first it considers the issue from a theoretical point of view – describes microfluidics as a newly developing and promising field of production of microfluidic devices, materials, biomedical applications and advantages and disadvantages of microfluidics overall. Furthermore, it focuses on an area of analytical utilization of enzymes within enzyme reactors. In the first part of the experimental section, conditions for the testing of enzymes of xenobiotics metabolism in the liver were optimized, namely the model of coumarin metabolism via the spectrofluorimetry method. The second part of the experimental work dealt with optimization of the fabrication conditions of microfluidic chips from OSTE (off-stoichiometry Thiol Ene) via the soft lithography method. Subsequently, the functionality of the produced chips was tested. Based on the results of both parts of the experimental work, an evaluation was carried out to assess the suitability of their interconnection for future research – screening of microsomal enzyme activity and model biotransformation of drugs within the channels of the fabricated devices.

Syftet med denna studie var att utvärdera behandling med hjälp av elektropalatografi (EPG) och portabel träningsenhet (PTU) hos en person med kvarstående artikulationsproblem. Försökspersonen var en vuxen man med medfödd hemifacial mikrosomi och mikrognati som tidigare genomfört konventionell talträning. En kvasiexperimentell, prospektiv, kontrollerad single subjekt A-B-A design användes. Försökspersonen hade vid träningsstart en tillbakadragen artikulation av /t/ och /d/ till velart/uvulart artikulationsställe med kvarstående svårighet att göra sitt tal förståeligt för sina samtalspartners.  Behandlingseffekten utvärderades genom instrumentell EPG analys av /t/ i enstaka ord före och efter behandling. Analysen visade signifikanta behandlingsresultat där en fortgående förbättring av produktionen av /t/ i medial och final position skedde även fyra år efter avslutad behandling. Perceptuell lyssnarbedömning av tränade och otränade lyssnare uppvisade signifikant förbättrad skattning av t-likhet av målljudet /t/ i medial och final position över tid. Ett mycket svagt samband sågs mellan perceptuell skattning av t-likhet och de analyserade EPG-värdena. Lyssnarskattningen av spontantalet visade en förbättring av förståelighet vid kontroll 4 år efter avslutad träning. Utvärderingen bekräftar tidigare forskning och visar att talträning med EPG är ett effektivt sätt att ge visuell återkoppling i försök att etablera ett korrekt artikulationsmönster, förbättrat tal och ökad förståelighet. Detta provades i föreliggande studie och även om resultaten inte var entydiga, antyddes att metoden kan vara långsiktigt framgångsrik vid sedan lång tid väl etablerade talavvikelser utan tecken på förändring spontant eller efter tidigare träning utan visuell återkoppling. En viktig erfarenhet är således att planera långsiktigt och invänta automatisering av nya artikulationsrörelser som har lång etableringsfas. Träning med EPG föreslås kunna erbjudas vuxna personer med kvarstående artikulationsavvikelser där konventionell träning inte har kunnat ge önskvärda resultat. Nyckelord: Elektropalatografi, behandlingseffekt, hemifacial mikrosomi, artikulationsstörning, långtidsuppföljning, förståelighet
The aim of this study was to evaluate speech therapy using electropalatography (EPG) and portable training unit (PTU) in a subject with persistent articulation errors. The participant was a male adult with congenital hemifacial microsomia and micrognathia who previously had received conventional speech therapy. The subject had a retracted, velar/ uvular articulation of dental plosives with difficulty making speech understandable to listeners. A quasi-experimental prospective, controlled single-subject ABA design was used. Treatment efficacy was assessed by instrumental EPG analysis of  /t/ in single words before and after treatment and showed significant treatment results with a continuing improvement in the production of  /t/ in medial and final position even four years after completion of treatment. Perceptual listen assessment of trained and untrained listeners showed significantly improved estimation of the target /t/ in medial and final position over time. A very weak association was found between the perceptual estimation of t-likeness and the analyzed EPG values. Listener rating of spontaneous speech showed an improvement in intelligibility 4 years after completing training. The evaluation confirms previous research showing that speech therapy with EPG seems effective for providing visual feedback in the attempt to establish a correct articulation pattern, improved speech and enhanced intelligibility. This was investigated in the present study and although the results were not unambiguous, it was indicated that the method can be successful at long persisting well established articulation errors without signs of spontaneous change or after previous training without visual feedback. An important experience is to plan long term and wait for the automation of the new articulation movements that have a long establishment phase. Training with EPG is proposed to be offered to adults with persistent articulation disorders for which conventional therapy has been unable to provide desirable results. Keywords:  Electropalatography, treatment effect, hemifacial microsomia, articulation disorder, long- term follow- up, intelligibility

The Kiirunavaara mine hosts one of the world’s largest apatite-iron ore mineralisations. This ore body has been subject to large amounts of research as well as extensive mining. The ore body is situated between the syenitic foot wall and the rhyodacitic hanging wall, of which consists of differing mineralogy and characteristics. Both these rock masses contain intrusive porphyry dykes, with distinct characteristics of it own. The aim of this study was to analyse 31 samples, mainly in the form of thin sections, and determine the mineralogy and identify eventual microstructures. This was done through the use of optical mineralogy as well as EDS/WDS analysis at the National Microprobe Lab at Uppsala University. The foot wall consists of syenite-porphyry and is dominated by feldspar in both groundmass as well as phenocrysts. Characteristic for the syenite-porphyry is the rounded nodules containing actinolite, titanite, magnetite and chlorite. The hanging wall is defined as quartz-bearing porphyry. It is a rhyodacitic rock with large amounts of feldspar along with green silicates, quartz, titanite and calcite. The intrusive porphyry dyke-rocks share many similarities with the quartz-bearing porphyry, but contain a finer groundmass with larger amounts of clinopyroxene, as well as lower amounts of quartz, magnetite and titanite. Hydrothermal alteration is prevalent in all the types of rock. Alteration minerals such as actinolite, biotite and chlorite are very common within the Kiirunavaara-rocks. The quartz-bearing porphyry displays the most extensive exposure to hydrothermal fluids. The hydrothermal fluids have penetrated several samples, replacing minerals and leaving very few remnant, older minerals. The quartz-bearing porphyry contains the most prominent deformation structures, of varying extent and magnitude. Magmatic flow structures can be seen in the groundmass, as parallel alignment of feldspar and silicate grains. Evidence of solid-state deformation most commonly occurs as pressure shadows around feldspar phenocrysts.
Kiirunavaara-gruvan är belägen vid en av världens största mineraliseringar av apatit-järnmalm. Denna malmkropp har stått i fokus för både omfattande gruvdrift samt genomgripande forskning. Malmkroppen är belägen mellan den syenitiska liggväggen och den ryodacitiska hängväggen, som består av varierande mineralogi och karaktär. Båda av dessa bergmassor innehåller intrusiv gångporfyr med distinkt karaktär. Målet med denna studie var att analysera 31 prover, främst i form av tunnsliper, och bestämma dess mineralogi samt att identifiera eventuella mikrostrukturer. Detta genomfördes genom användning av optisk mineralogi och EDS/WDS-analys vid det nationella mikrosondslaboratioriet vid Uppsala Universitet. Liggväggen består av syenitporfyr och domineras av fältspat i både mellanmassa och som fenokrister. Karaktäristiskt för syenitporfyren är de rundade nodulerna, innehållandes aktinolit, titanit, magnetit och klorit. Hängväggen definieras som kvartsförande porfyr. Det är en ryodacitisk bergart med stora mängder fältspat, gröna silikater, kvarts, titanit och kalcit. Gångporfyren delar många likheter med den kvartsförande porfyren, men består av en finare mellanmassa med större mängd klinopyroxen, samt innehåller mindre mängder kvarts, magnetit och titanit. Hydrotermal omvandling är allmänt förekommande i alla bergarter i Kiirunavaara. Omvandlingsmineral så som aktinolit, biotit och klorit är väldigt vanliga hos Kiirunavaara-bergarterna. Den kvartsförande porfyren uppvisar den mest omfattande exponeringen av hydrotermala vätskor. De hydrotermala vätskorna har penetrerat ett antal prover och därigenom omvandlat mineral, med liten mängd äldre mineral kvar. Den kvartsförande porfyren innehåller de mest prominenta deformationsstrukturer, av olika omfattning och magnitud. Magmatiska flytstrukturer kan observeras i mellanmassan som parallell orientering av fältspat- och silikatkorn. Tecken av fastfasdeformation förekommer främst i form av tryckskuggor runt fältspatsfenokrister.

The aim of the thesis was to develop a new method of measurement, enabling the study of local thermal properties of solids with high spatial resolution. To develop the new method of measurement the scanning thermal microscope was utilized. Research carried out in the framework of this study included theoretical and numerical analysis as well as experimental work. In the first part of the thesis a model of the probe - sample system is presented, created basing on the finite element method. The model allows a comprehensive analysis of the physical processes occurring in the probe - sample system during the measurement. Numerical analysis allowed to determine the optimal conditions for experimental research, estimate the maximum probe sensitivity to thermal properties and model different modes of quantitative measurements. An important result of this part of research was developing a correction procedure for determining the thermal conductivity of a thin film. In the next part of the thesis a model of heat transport processes in the probe - sample system, which based on electro-thermal analogies, was proposed and experimentally verified. It was shown that the developed model allows to achieve better compliance with the measurement results than the models used so far and that it is helpful in the analysis and interpretation of the results obtained in different modes of measurement. The main goal of the work was to propose a new method of measurement. It utilizes the dc biased probe with small ac current superimposed to it. The static and dynamic resistance of the probe are measured. The method combines the advantages of both dc and ac excitation, such as: mechanical stability of the probe, average temperature control, lock-in signal processing, higher signal to noise ratio. A new way of analyzing the results of the measurements was proposed, in which the difference between dynamic and static resistance of the probe is calculated. It was shown that it is directly proportional to the thermal resistance of the probe, which contains information about the thermal conductivity of the sample. Utilizing the probe signal measured in air is a reference, minimizes the influence of the instability of ambient conditions. It was shown that the sensitivity to the thermal properties is higher than in the standard measurement methods. Experimental studies included the verification of the correctness of proposed measurement method and its use to investigate thermal properties of selected micro- and nanostructures. The results of investigations of multi-layer photonic structures, TSV structures and thin SiO2 and BaTiO3 layers were presented. It was shown that the proposed method of signal detection and analysis can be used both in the classical methods of thermal imaging as well as in the quantitative measurements. Results of research carried out in the framework of this thesis and utilizing the developed measurement method were published in 7 scientific papers. The results of the research were presented at several presentations at international conferences.

This work deals with the theoretical foundations of electron emission into vacuum, various types of emissions, focused on the cold-emission and Schottky emission and the principle of quantum tunneling. The next part deals with the technical implementation of electron sources with a detailed study of the methodology of laboratory production of cathodes by electrochemical etching and construction of electron microscopes, using field-emission sources. This work also contains methods for measuring, processing and evaluation of electrical characteristics of emission sources.

In this thesis, the impact of atenolol, verapamil, dexamethasone, clotrimazole, and PBSA on the physiological condition and health of rainbow trout (Oncorhynchus mykiss) were studied in vivo and in vitro. The sub-chronic test of atenolol, including at the environmentally relevant concentration, demonstrated that only the fish exposed to atenolol at a concentration of 1000 ?g?L-1 may be at a higher risk of oxidative stress. The second pharmaceutical compound studied was an L-type calcium channel blocker, verapamil. Despite the relatively high concentration of verapamil included in the experiments, the rates of seven hepatic CYP450-mediated reactions (EROD, MROD, PROD, BFCOD, COH, and PNPH) were unchanged in the exposed rainbow trout. This indicates that the activities of the selected CYP450 enzymes were not affected. Exposure to the highest concentration of PBSA (1000 ?g?L-1) led to significantly inhibited glutathione reductase activity. The activities of the EROD, MROD, and PROD enzymes gradually increased, beginning at the environmentally relevant concentrations. We suggest that long-term exposure to PBSA could cause oxidative stress in fish, as indicated by the decreased activity of GR. Moreover, PBSA could interact with intracellular receptors due to the elevated activities of CYP1A (EROD and MROD) and CYP2B (PROD). Rainbow trout showed multiple responses after exposure to clotrimazole. Changes in the haematological parameters in the exposed rainbow trout suggested that the immune system and haemoglobin synthesis were affected. The antioxidant defence enzymes that responded to the clotrimazole exposure influenced the oxidative stress status of the fish. Sub-chronic exposure to clotrimazole did not lead to oxidative stress in any of the fish tissues studied, as indicated by the unchanged TBARS levels. Hepatic energetic pathways were activated in the tested groups after 42 days of exposure to clotrimazole. High levels of glutathione S-transferase were seen in the liver and gill tissues, possibly associated with the detoxification of clotrimazole. The interaction of clotrimazole with intracellular receptors can be expected due to the changes in the catalytic activities of CYP1A1 and CYP3A. The BCF levels in the muscle tissue suggest a moderate bioaccumulation of CLO. The relatively long elimination period for CLO in the fish kidney (half-life = 29 days) may imply a greater potential for adverse effects in this organ. This finding is significant in view of the structural disturbances that appeared in the kidney and testis. The changes observed in the kidney were most prominent in the tubular epithelial cells. Changes in the gonads were only visible in the male specimens, and the pathological changes in the testis may indicate a disruption of steroidogenesis. The potential of clotrimazole and dexamethasone to inhibit CYP450 enzyme activity in rainbow trout hepatic microsomes was investigated in vitro. Clotrimazole non-competitively inhibited EROD activity in the hepatic microsomes, while BFCOD activity was competitively inhibited. PNPH activity was only slightly reduced in the presence of clotrimazole, indicating that it does not significantly interact with CYP2E1. The presence of dexamethasone in the incubations did not affect any of the CYP450 enzymes investigated. Everything considered, the results of the study confirmed that the presence of clotrimazole in the environment is of concern with respect to its impact on the health status of fish. In this thesis, the data of the actual effects of several PPCPs on fish were discussed. Based on the response of selected molecular endpoints, the cardiovascular and anti-inflammatory drugs studied do not present a significant risk for fish, while the antifungal drug and UV-screening agent that were tested may disrupt several physiological processes in fish.

The consumption of dietary supplements such as flavonoids may reduce risk of many civilization diseases. Flavonoids are able to modulate the activity of cytochromes P450 (CYPs), xenobiotic-metabolising phase I enzymes of biotransformation that are involved in the activation and detoxification of food-derived carcinogens. Inhibition of CYP activities by flavonoids has been extensively studied because of their potential use as agents blocking the initiation stage of carcinogenesis. On the other hand, flavonoids have been shown to enhance the activation of carcinogens and/or influence their metabolism via induction of specific CYPs. In the first part of this study, flavonoids dihydromyricetin and α-napthoflavone were explored for their possible effects on CYP1A1 expression and activity when administered in combination with carcinogen benzo[a]pyrene (BaP). For this purpose, liver, small intestine and colon microsomal fractions were isolated from treated rats and induction of CYP1A1 was evaluated by immunodetection and EROD activity measurements. In liver and small intestine, all combinations of BaP and flavonoids led to strong induction of CYP1A1 expression. Moreover, the CYP1A1 protein levels were almost identical to levels observed when the rats were treated with BaP alone. However, in comparison...

I have set for a challenging study that combined experimental and theoretical approaches in an attempt to resolve a role of small aminoacids in intermolecular interactions. First, I have proposed a hypothesis that described the interaction among individual aminoacids forming D helices of D1 and D2 proteins based on molecular dynamic simulations of a simplified model representing the reaction centre of photosystem II. Stability of the putative interhelical hydrogen bond network connecting D1 and D2 proteins was investigated experimentally with dynamic force spectroscopy using atomic force microscope. The results of both methods are in a full agreement with each other and reveal the key role of D1-Gly208 aminoacid in stability and functionality of photosystem II by providing milieu for weak interactions among three contact points at the cross of D helices: D1-Gly208 (O) and D2-Cys211 (O?), D1-Ser209 (O?) and D2-Ile204 (O), D1-Ser212 (O?) and D2-Gly207 (O). Mutation of the D1-Gly208 led to the increase in probability of the binding among the aforementioned aminoacids, undesirably strengthening the overall interactions among the proteins compromising photosynthetic capacity (D1-Ser208) or disabling of autotrophic growth (D1-Val208).