Tryptophan is metabolised along the kynurenine pathway under the influence of tryptophan 2,3 dioxygenase and indoleamine 2,3 dioxygenase. Quinolinic acid and kynurenine, two neuroactive metabolites of the kynurenine pathway are, in chronic renal failure patients, considered as uraemic toxins. Related research is generally hampered by the non-availability of relevant analytical techniques. The primary aim of this study was, therefore, to develop and validate suitable methods for the determination of tryptophan, kynurenine and quinolinic acid. The second aim was to quantify the levels of these substances in the blood of chronic renal failure patients on renal replacement therapies and to compare the levels of haemodialysis patients to those on peritoneal dialysis. Patients’ quality of life was investigated relative to disturbances in tryptophan metabolism. Gas chromatography coupled to mass spectrometry (GC-MS) gave the best results for the analysis of tryptophan, kynurenine and quinolinic acid. A Hewlett Packard HP GC 6890 series gas chromatographer was coupled to a MS 5973 series mass spectrometer. Analytes were separated on a DB-5MS column with a nominal length of 30 metres, a diameter of 250.0 µm and film thickness of 0.10 µm. Helium was used as carrier gas, and the chromatographic analysis run time 12.5 minutes. The validation results were within the acceptance criteria for newly developed methods. The linear calibration curves constructed for all of the analytes gave r2 correlation coefficients >0.99. Other validation data such as precision, bias, accuracy and stability all fell within acceptable validation limits. In the study on chronic renal failure patients significant differences were seen between patients and controls. Tryptophan levels were 5.34 SD 5.04 µM for the haemodialysis group, 6.73 SD 3.18 µM for the peritoneal dialysis group and 28.4 SD 4.31 µM for the control group. Kynurenine levels were 4.7 SD 1.9 µM for the haemodialysis group, 2.9 SD 2.0 µM for the peritoneal dialysis group and 2.1 SD 0.6 µM for the control group. Quinolinic acid levels were 4.9 SD 2.0 µM for the haemodialysis group, 2.8 SD 2.0 µM for the peritoneal dialysis group and 0.3 SD 0.1 µM for the control group. Tryptophan was lower for the total patient group than for controls with significantly lower levels for haemodialysis versus control (p<0.05) and peritoneal dialysis versus control (p<0.05). Kynurenine levels were higher in the total patient group with significantly higher levels for the haemodialysis versus control group (p=0.0001). The patient groups had higher quinolinic acid levels with significantly higher levels for the haemodialysis versus control (p<0.05) and peritoneal dialysis versus control (p<0.05) groups. This study was the first to determine the three substances simultaneously in both haemodialysis and peritoneal dialysis patients. The study showed significant tryptophan depletion, as well as kynurenine and quinolinic acid accumulation for both groups. No significant differences were found between the patient groups other than higher kynurenine levels in the haemodialysis group. The quality of life (SF-36) was largely similar in the two patient groups. This decrease in the quality of life strongly correlated with the degree of tryptophan depletion. / Dissertation (MSc)--University of Pretoria, 2008. / Chemical Pathology / unrestricted

Orientadores: Cesar Costapinto Santana, Isabel Cristina Sales Fontes Jardim / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-08T01:29:34Z (GMT). No. of bitstreams: 1 Maldaner_Liane_M.pdf: 1508589 bytes, checksum: 3a427ebd108b6fdad8d08be5f356992c (MD5) Previous issue date: 2007 / Resumo: A soja é um dos principais produtos de exportação do Brasil, sendo muito empregada na alimentação, por ser um alimento funcional, rico em vitaminas, proteínas e sais minerais. A crescente demanda e a busca da qualidade da soja exigem a aplicação constante, de agrotóxicos durante o seu cultivo, sendo as vezes abusiva. Por outro lado, para garantir o bem estar da população, uma vez que a maioria dos agrotóxicos são prejudiciais à saúde, as principais agências reguladoras impõem limites máximos de resíduos para os agrotóxicos que podem estar presentes nos alimentos. Em vista disso, neste trabalho, foi desenvolvido e validado um método para determinação dos principais agrotóxicos (imazetapir, imazaquim, metsulfurom-metil, carboxim, clorimurom-etil e tebuconazol) usados nas lavouras de soja, empregando a dispersão da matriz em fase sólida (DMFS) como técnica de extração, seguida de uma etapa de cIean-up e posterior análise por cromatografia líquida de alta eficiência com detecção por arranjo de diodos (CLAE-DAD). Os resultados mostraram que a DMFS é adequada para amostras sólidas e complexas, como a soja, é rápida e simples, entretanto, exige a otimização de várias variáveis durante o processo de desenvolvimento da metodologia. A etapa de cIean-up foi necessária devido a quantidade de int~rferentes provenientes da matriz, que foram, na sua maioria, eliminados com o uso de uma co-coluna de C8. Permaneceram interferentes que co-eluíram nos tempos de retenção do imazetapir e do'metsulfurom, que não invalidaram suas determinações, mas prejudicaram suas quantificações. A validação da metodologia mostrou bons resultados de recuperação para todos os agrotóxicos (60 -120 %), com exceção para o metsulfurom e tebuconazol no nível mais baixo de concentração; precisão < 15 % para todos os compostos, com exceção do imazetapir e metsulfurom; boa linearidade, coeficientes de correlação> 0,90 e nenhuma tendência foi visualizada no gráfico de resíduos. O limite de quantificação do método permitiu que os limites máximos de resíduos impostos pelas agências reguladoras para todos os compostos estudados fossem atingidos, com exceção para o imazetapir, devido a co-eluição do interferente. As amostras provenientes de uma cultura de soja analisadas não apresentaram contaminação pelos agrotóxicos em estudo / Abstract: Soy is one of principal Brazilian exportation products of Brazil as it is much used as a foodstuff because of its functional properties: rich in vitamins, proteins and minerais. The increasing quantity and quality of soy demands a constant and even expressive application of pesticides during soy cultivation. On the other hand, for preservation of public heath, since most pesticides may be prejudicial to health, the main regulatory agencies impose the maximum residues limits of pesticides in food. Thus, in this work, a method to determine the main pesticides applied in soy cultivation (imazethapyr, imazaquin, metsulfuron-methyl, carboxin, chlorimurom-ethyl and tebuconazole) using matrix solid phase dispersion (MSPD) as the extraction technique, followed by a clean-up step and subsequent chromatographic analysis by high performance liquid chromatography - diode array detection (HPLC-DAD), was developed and validated. The results have shown that MSPD is a suitable extraction procedure for solid and complex matrices, as is the case of soy and is a rapid and simple technique. However, it requires the optimization of some variables during the process of methodology development. The clean-up step was necessary because of the amount of matrix impurities, but the majority was eliminated using a C8 co-column. Remaining im.purities with the same retention time as imazethapyr and metsulfuron do not invalidate the determination but prejudice the quantification of these compounds. The validated method has shown good -results of recuperation for ali pesticides (60 - 120 %) except for metsulfuron and tebuconazole at the lowest concentration levei, precision < 15 % for ali compounds, except for imazethapyr and metsulfuron, good linearity and correlation coefficients > 0.90 without visible bias. The quantification limit of the method allows determinations below the maximum residues limits for ali pesticides, except for the imazethapyr, due to the presence of an impurity. Soy samples from soy cultivation were analyzed and did not present contamination for the pesticides under study / Mestrado / Desenvolvimento de Processos Biotecnologicos / Mestre em Engenharia Química

Orientador: Helena Teixeira Godoy / Dissertação (mestrado) Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-18T11:10:27Z (GMT). No. of bitstreams: 1 Dias_CintiaBotelho_M.pdf: 1034567 bytes, checksum: b951b7499377a9819a5bcb0cf7b70dd8 (MD5) Previous issue date: 2011 / Resumo: Um novo metodo rapido, eficiente e economico para a determinacao de cinco edulcorantes (acessulfame-K, sacarina sodica, ciclamato de sodio, aspartame e neotame) pela tecnica de cromatografia liquida de ultra performance (UPLC) foi desenvolvido, validado e aplicado na analise de alguns produtos diet, light e zero recorrentemente encontrados em supermercados. Para a otimizacao do metodo foi utilizado um delineamento composto central e a otimizacao simultanea de respostas foi realizada por meio da funcao de desejabilidade de Derringer e Suich. Foi empregada uma coluna de fase reversa C18, fase movel composta de acetonitrila e tampao fosfato de sodio 5 mM/ acido orto-fosforico (pH 3,0) com eluicao por gradiente e vazao de 0,4mL/min, com temperatura de coluna a 56oC. Os cinco compostos responderam linearmente em diferentes faixas de concentracao aplicaveis as concentracoes presentes nas amostras. A precisao intra e inter dias, bem como os limites de deteccao e quantificacao variaram para os cinco edulcorantes. As taxas de recuperacao para os edulcorantes avaliados variaram entre 70 e 115% para as diferentes matrizes analisadas. O metodo foi aplicado em refrigerantes, nectares e sucos, chas prontos para beber, pos para preparo de refresco, pudins e cappuccinos, achocolatados, geleias, catchup e molho tipo ¿barbecue¿. No entanto, algumas limitacoes foram encontradas para a quantificacao do neotame e ainda para alimentos contendo cacau em sua formulacao quanto a identificacao do ciclamato de sodio. Foram encontradas amostras contendo ate quatro edulcorantes em combinacao em um mesmo produto. Dentre os mais utilizados estavam o acessulfame e o aspartame. Algumas das amostras apresentaram ainda concentracoes acima das permitidas pela legislacao brasileira e, dentro dos edulcorantes estudados, nenhum edulcorante nao declarado foi encontrado. O metodo desenvolvido por UPLC foi comparado a uma metodologia por cromatografia liquida de alta eficiencia (HPLC). A UPLC apresentou melhor resolucao e menores limites de deteccao e quantificacao, tempo de analise mais curto e menor gasto de solvente. Entretanto, a HPLC ainda foi mais robusta / Abstract: A new, fast, efficient and economic method for the determination of five sweeteners (acesulfame-K, saccharin, cyclamate, aspartame and neotame) by ultra performance liquid chromatography (UPLC) has been developed, validated and applied to diet, light and zero products usually found in supermarkets. A central composite design was used and also the simultaneous optimization of the answers was carried using the Derringer's desirability function for the method optimization. A C18 reversed phase column was used and the optimized method resulted in a binary eluent consisting of acetonitrile and sodium phosphate 5 mM/ ortophosphoric acid buffer (pH 3.0) in gradient elution, 0.4 mL/min flow rate and 56oC column temperature. The five compounds behaved linearly in different concentration ranges applicable to the concentrations in the samples and the precision intra and inter-day, as well as the limits varied for those sweeteners. The recoveries for the evaluated sweeteners varied for the distinct sample matrices from 70 to 115%. The method was applied to the sweeteners determination in soft drinks, fruit juice beverages, ready to drink teas, powder juice, pudding, cappuccino, chocolate powder, jellies, barbecue sauce and ketchup. However, limitations were found on the quantification of neotame and on the products containing cocoa, in which it is not possible to identify the sodium cyclamate. Samples containing up to four distinct sweeteners in synergism were found. Acesulfame and aspartame were the most used sweeteners among the analyzed samples. Although, non declared sweeteners were not found among those studied, their quantities in some samples were above the allowed in the Brazilian regulation. Afterwards, the UPLC developed method was compared with a high performance liquid chromatography (HPLC) method. The UPLC method presented the best resolution, the lowest detection and quantification limits, shortest retention time and lest solvent waste. However, HPLC is more rugged than UPLC / Mestrado / Engenharia de Alimentos / Mestre em Ciência de Alimentos

Orientador: Donizete Cesar Honorato / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-14T10:24:14Z (GMT). No. of bitstreams: 1 Paraizo_MarceloFabianoNovaes_M.pdf: 2543804 bytes, checksum: 2a802bede492d07cf65fbed6a2a764f1 (MD5) Previous issue date: 2009 / Resumo: O Acidente Vascular Encefálico (AVE) é a doença cerebrovascular que apresenta maior incidência e resulta em incapacidades. Um instrumento que se proponha a avaliá-los deve ter suas propriedades psicométricas estudadas. O Postural Control and Balance for Stroke Test (PCBS) foi desenvolvida por Pyöria e col. e publicado na língua inglesa no ano de 2005. O instrumento avalia mudanças posturais, equilíbrio sentado e em pé. Sendo este um instrumento importante para a área da reabilitação foi realizada a tradução para a língua portuguesa por quatro profissionais bilíngües e averiguada a confiabilidade e validade da versão brasileira da PCBS . O título da versão brasileira ficou definido como Escala de Controle Postural e Equilíbrio para Acidente Vascular Encefálico (ECPE-AVE). Com esta finalidade, 21 indivíduos acometidos por AVE foram avaliados, buscando conhecer a sua consistência interna, a confiabilidade inter-observador e a sua correlação com outras variáveis. Foi encontrada uma excelente consistência interna, Coeficiete Alfa de Cronbach, muito próximos de um para todos os quatro examinadores, todos os scores > 0.8. A confiabilidade inter-observador foi significativa, com scores acima de 0,75, no Coeficiente de Correlação Interclasses e p-valor < 0.05. A ECPE-AVE também demonstrou correlação com a maioria das variáveis às quais foi comparada. Assim o instrumento de avaliação ECPE-AVE, teve sua confiabilidade e validade avaliativa comprovada e pode ser utilizado, pelo meio acadêmico e científico, na caracterização e acompanhamento dos déficits do controle postural e equilíbrio causado por um AVE. / Abstract: Stroke is a cerebrovascular disease with a high incidence and with high impairment. In order to evaluate a stroke patient, the instrument should have the psychometric properties studied. The Postural Control and Balance for Stroke Test (PCBS) was developed by Pyöria et. al. and was published in the English language in 2005. This instrument evaluates postural changes and seating and standing balance. Since this is an important instrument for the rehabilitation field, a translation for the Portuguese language was performed by four bilingual professionals and tested regarding its reliability and validity. The Brazilian title of the scale is "Escala de Controle Postural e Equilíbrio para Acidente Vascular Encefálico (ECPE-AVE)". In order to verify the internal consistence and reliability interrator, twenty one stroke subjects were evaluated, and the results were correlated with other variables. There was a high internal consistence, with Cronbach alpha coefficient close to one for all the four evaluators, Cronbach alpha coefficient > 0.8 in all the scores. The interrator reliability was significant, with scores higher than 0,75, in the Coeficiente de Correlação Interclasses and p < 0.05. The ECPE-AVE also showed correlation with almost all variables compared. Thus, the evaluation instrument ECPE-AVE is a reliable and validated instrument and can be used to characterize and to evaluate the development of postural control and balance deficits after stroke. / Mestrado / Ciencias Biomedicas / Mestre em Ciências Médicas

De nombreuses études dans la seconde moitié du 20ème siècle, ont mis en évidence que des génotoxiques cancérogènes réagissent avec l'ADN pour former par liaison covalente des adduits qui sont impliqués dans le processus cancérigène. Bien qu’il existe des preuves convaincantes de la présence de multiples adduits à l'ADN dans les poumons de sujets exposés au tabagisme ou en milieu professionnel à un aldéhyde donné, il est évident que c'est un domaine dans lequel des recherches supplémentaires ont été nécessaires. L’objectif de ce travail de thèse est d’établir des profils d’adduits exocycliques à l'ADN induits par le mélange d’aldéhydes, qui pourraient à terme être considérés comme un marqueur génotoxique de l’exposition aux aldéhydes, tant endogène qu’environnemental. Pour cette raison, nous avons validé une méthode en UHPLC-MS/MS rapide, sensible et précise en utilisant la dilution isotopique, pour la quantification à l’état de trace de 9 adduits exocycliques à l’ADN dérivés de 8 principaux aldéhydes exogènes et endogènes, notamment le formaldéhyde, l’acétaldéhyde, l’acroléine, le crotonaldéhyde, le malondialdéhyde, le 4-hydroxy-2-nonénal, le glyoxal et le méthylglyoxal. Ces adduits ont été synthétisés et purifiés ainsi que leurs homologues marqués au 13C10, 15N5, identifiés et quantifiés par le biais des courbes d'étalonnage allant de 0,25 à 250 ng/mL d'adduits dans l'eau et l'ADN afin de décrire les effets matrice. Des échantillons de contrôle qualité ont été préparés et analysés afin de vérifier l'exactitude et la précision de la méthode dans des situations de répétabilité et de fidélité intermédiaire. L'absence de contamination croisée a également été démontrée. La méthode est capable de différencier les 9 analytes d'intérêt et leurs étalons internes en utilisant pour chaque analyte une transition de quantification et une seconde de confirmation. Cette méthode a été validée selon les recommandations de l'Agence Européenne des Médicaments concernant les méthodes bioanalytiques. Elle répond à tous les critères essentiels pour garantir l'acceptabilité des performances et la fiabilité des résultats d'analyse. Cette méthode est la toute première validée et peut être utilisée en adductomique dans le cadre d'études sur l'exposome. En plus, nous avons simultanément mesuré par une approche in vitro les 9 adduits exocycliques dans de l’ADN de thymus de veau exposé à de différentes concentrations de chaque aldéhyde seul ou en mélanges équimolaires. Cette approche nous a permis d’établir des relations dose-dépendantes pour tous les aldéhydes à l’exception du malondialdéhyde et du méthylglyoxal. Une relation dose-réponse a également été observée avec les mélanges équimolaires d’aldéhydes. Elle a permis de définir des réactivités différentes des aldéhydes en mélange vis-à-vis de l’ADN. Les profils de ces adduits exocycliques ont été également déterminés dans l'ADN de sang de fumeurs et de non-fumeurs. La fumée de cigarette contient plusieurs aldéhydes connus de se lier par covalence aux bases de l’ADN, ainsi l’adduit à l’ADN peut être considéré comme biomarqueur d’exposition au tabac. Des différences significatives dans les niveaux d’adduits ont été obtenues entre l’ADN des fumeurs et celui des non-fumeurs à l’exception de l’adduit induit par le malondialdéhyde. Des corrélations ont été établies entre chaque adduit et les marqueurs de la consommation tabagique sans aucune corrélation significative de la totalité des adduits avec un marqueur spécifique. Par ailleurs, nous avons montré que l’exposition au formaldéhyde, au butanal et au benzaldéhyde a eu un effet sur les concentrations du MDA urinaire mesurées chez les policiers libanais stationnés au carrefour pendant 7 h par jour et après exposition de 5 jours aux émissions du trafic routier. Une augmentation du MDA plasmatique a été décrite ; les années de travail avaient une incidence sur les concentrations de ce biomarqueur. / Many studies in the second half of the 20th century have shown that genotoxic carcinogens, either directly or after metabolic activation, react with DNA to form covalently bonded adducts that are absolutely central in the carcinogenic process. Although there is compelling evidence of the presence of multiple DNA adducts in the lungs of subjects exposed to smoking or occupational exposure to a given aldehyde, it is clear that this is an area in which further research has been necessary. The aim of this thesis is to establish exocyclic DNA adducts profiles induced by the mixture of aldehydes, which could eventually be considered as a genotoxic marker of aldehyde exposure, both endogenous environmental. For this reason, we have validated a fast, sensitive and precise method on liquid chromatography coupled to mass spectrometry in tandem mode (UHPLC-MS/MS) using isotopic dilution, for trace quantification of 9 exocyclic DNA adducts derived from 8 major exogenous and endogenous aldehydes, including formaldehyde, acetaldehyde, acrolein, crotonaldehyde, malondialdehyde, 4-hydroxy-2-nonenal, glyoxal and methylglyoxal. These adducts were synthesized and purified as well as their labeled homologues, identified and quantified through standard curves ranging from 0.25 (LLOQ) to 250 ng/mL (ULOQ) adducts in water and in DNA to describe the matrix effects. Quality control (QC) samples were prepared and analyzed to verify the accuracy and precision of the method in repeatability and intermediate fidelity situations. The absence of cross-contamination has also been demonstrated. The method is able to differentiate the 9 analytes of interest and their internal standards using for each analyte a quantification transition and a confirmation transition. This method has been validated according to the recommendations of the European Medicines Agency (EMA) concerning bioanalytical methods. It meets all the essential criteria to guarantee the acceptability of the performances and the reliability of the analysis results. This method is the very first validated and can be used in adductomics in the context of studies on the exposome. In addition, the exocyclic adducts were simultaneously measured by an in vitro approach in calf thymus DNA exposed to different concentrations of each aldehyde apart or in equimolar mixtures. This approach allowed us to establish dose-dependent relationships for all aldehydes with the exception of malondialdehyde and methylglyoxal. A dose-response relationship was also observed with equimolar mixtures of aldehydes. It made it possible to define different reactivities of aldehydes in mixture versus DNA. The profiles of these exocyclic adducts were also determined in the blood DNA of smokers and non-smokers. Cigarette smoke contains several aldehydes known to covalently bind to DNA bases, so the DNA adduct may be considered as biomarker of tobacco exposure. Significant differences in adducts levels were obtained between smokers and non-smokers DNA with the exception of malondialdehyde-induced DNA adduct. Correlations were established between each adduct and smoking-related markers without any significant correlation of all adducts with a specific marker. Furthermore, we have shown that exposure to formaldehyde, butanal and benzaldehyde had an effect on the concentrations of urinary MDA measured in Lebanese police stationed at the intersection for 7 hours a day and after 5-day exposure to road traffic. An increase in plasma MDA has been described; years of work had an impact on the concentrations of this biomarker. These results are promising and it would be interesting to validate in population the profile of 9 exocyclic adducts as biomarkers of exposure to both exogenous and endogenous aldehydes as part of an adductomic approach to understand the carcinogenic risk in relation to aldehydes exposures in urban areas.

Les éléments traces (ET) se trouvent naturellement dans l’environnement. Ces dernières années, des apports croissants en ET sont induits par des activités anthropiques, causant des problèmes environnementaux surtout dans le milieu marin. Certains ET sont toxiques et le besoin de méthodes fiables pour leur analyse dans des échantillons environnementaux est indéniable. À travers cette thèse, des méthodes analytiques ont été développées et validées pour l’analyse des ET dans les sédiments et les organismes marins par spectrométrie d’absorption atomique à source continu, haute résolution et introduction solide directe (SS-HR-CS-AAS). Des études environnementales basées sur l’utilisation de cette méthode et d’autres ont été réalisés. Une première étude a été réalisée sur des sédiments (de surface et carottes) collectés en Namibie. Cette thèse présente une série inédite de concentrations de base sur la côte namibienne. Une contamination importante en Pb, Cu, Zn et Cd a été démontrée autour des zones les plus peuplées. Les pollutions au Pb et leurs sources ont été étudiées grâce aux rapports isotopiques du Pb. Une deuxième étude a été réalisée sur différentes espèces d’éponges marines et des sédiments collectés en France et en Irlande. Il est montré que les éponges accumulent plus les ET que les sédiments et de façon différente selon les espèces. Des analyses de spéciation de l’arsenic ont été réalisées sur les éponges par chromatographie liquide haute performance couplée à un ICP-MS. Les résultats ont montré une bioaccumulation très importante de ce métalloïde dans les éponges et sa biotransformation des formes inorganiques en formes organiques beaucoup moins toxiques. / Trace elements (TE) naturally occur in the environment but their inputs have been increasing by anthropogenic activities in the last decades, causing environmental concerns, particularly in coastal ecosystems. TE are toxic and the need of reliable methods for their determination in environmental samples is undeniable. The first part of this PhD was focused on the development and full validation of methods for the analysis of TE in sediments and marine organisms by Solid Sampling High Resolution Continuum Source Atomic Absorption Spectrometry (SSHR-CS-AAS). Second, environmental studies based on these and others methodologies were then performed. A first monitoring survey was performed on sediments (surface and core samples) collected along the Namibian coast. This thesis provides the first baseline of TE contents and historical record of pollution in the area. Significant Pb, Cu, Cd and Zn enrichments were highlighted around the most populated areas, providing a needed baseline for present and future evaluation of the Namibian marine environment. Pb pollutions and their sources were also tracked through the use of Pb isotope ratios. A second monitoring survey was performed on different marine sponges and sediments collected in the French Mediterranean and in the Irish coasts. This work showed that sponges accumulate more TE than sediments in different extents according to species. Arsenic speciation analysis was performed in sponges by High Performance Liquid Chromatography (HPLC) coupled with ICP-MS. This special focus on arsenic highlighted the great bioaccumulation of this metalloid in sponges and its biotransformation from inorganic forms to less toxic organic forms.

This dissertation focuses on available means of the assessment of cognitive functions in neurological patients in the Czech environment. The main goal was to verify the psychometric qualities and usability of the Czech version of the Neuropsychological Assessment Battery (NAB). NAB is a test battery that assesses attention, language, memory, and spatial and executive functions. The theoretical part of the dissertation introduces the basic cognitive functions and diagnostic tools for their assessment; the next chapter focuses on NAB and especially its psychometric characteristics. Third chapter describes specific diseases (epilepsy and psychogenic seizures), their manifestations and impact on cognition. Empirical part included participation in the adaptation of NAB to the Czech language. During the research, a group of healthy volunteers (n = 116) and patients from the Epilepsy Monitoring Unit (n = 60) were tested by the NAB Screening Module. To verify the convergent validity of NAB-SM we administered Repeatable Battery for the Assessment of Neuropsychological Status (including an Effort Index) to a part of the sample. Based on the results, we can conclude that NAB-SM appears to be a suitable method for the assessment of cognitive functions in patients with psychogenic non-epileptic seizures. The...

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Lubricant is a common name for a large group of products that are essential for almost every engine or other machinery equipment that include mechanical part movements. Their main application is reduction of the friction between two rubbing surfaces by interposing a lubricating film between them. Other important functions of lubricants beside lubrication are; heat transfer, energy efficiency enhancement, corrosion and oxidation protection. All types of lubricants mainly consist of base oil and additives. Base oils are mainly hydrocarbon compounds, while additives are various chemical compounds added to the base oil to enhance some of the already existing properties, or to impose new properties that are beneficial for application purposes. During the storage period, where different storage conditions can occur, many of the requirements for lubricants chemical and physical stability needs to be fulfilled. Inappropriate storage conditions can cause physical and chemical changes in lubricants, which can make them unusable for the intended application. The effects of different storage conditions on lubricants stability were investigated in this work. The experimental part of this project was conducted at Fuchs Lubricants Sweden AB. At the beginning of the experiment, twelve 2L high density polyethylene bottles (HDPE) filled with the lubricant, were divided into three groups. The first group consisted of four closed HDPE bottles previously filled with the lubricant that were stored at 9 °C, 22 °C, 45 °C and 80 °C. The second and the third group consisted also of four open bottles and four bottles with added distilled water stored at the same storage temperatures. The amount of lubricant was approximately the same in all bottles. At different time intervals sample aliquots from the top, middle and the bottom layer were taken from these bottles and analyzed. The effects of different storage conditions on the lubricant’s stability and homogeneity were acquired by two distinctive spectroscopic methods. Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) was used for elemental composition analysis, while the Fourier Transform Infrared (FTIR) Spectroscopy was used for evaluation of chemical changes on molecular level. Results from ICP-AES analyses showed almost homogeneous elemental distribution, virtually unaffected by different storage conditions in all sample bottles. Results from FTIR analyses showed that observed changes in absorption peaks (673, 863, 972. and 1267 cm-1) took place almost simultaneously at all three layers in all bottles stored at four different temperatures. These results suggest that the analyzed lubricant was stable and homogeneous for the observed period. The lowest storage temperature caused minimal changes in the lubricant and can be considered as optimal storage temperature for this product. It was also observed that increased temperature, direct exposure to oxygen and presence of water catalytically affected the rate of these changes. A part of this project was to validate the method used for ICP analysis. For this purpose, the following method performance parameters were investigated: linearity, precision, accuracy, Limit of detection (LOD) and Limit of quantification (LOQ). The obtained results showed that linearity of the method for all elements, in the used standard, was confirmed based on the set criteria. Precision and accuracy were tested in repeatability conditions and at four different concentration levels. The obtained results showed that accuracy of the method increased with concentration, and was highest for 50 ppm, for almost all elements. The highest precision (&lt; 2 % RSD), for almost all elements was obtained for the concentration of 25 ppm. The LOD values were between 0.01 and 1.42 ppm while calculated LOQ values were between 0.04 and 4.73 ppm. / Smörjmedel är det gemensamma namnet för en stor produktgrupp som är nödvändig för nästan alla motorer eller annan maskinutrustning som inkluderar mekaniska delrörelser. Deras huvudsakliga tillämpning är att minska friktionen mellan två ytor i rörelse genom att införa en smörjfilm mellan dem. Andra viktiga funktioner förutom smörjning är; värmeöverföring, energieffektivisering, korrosion-och oxidationsskydd. Alla typer av smörjmedel består huvudsakligen av basolja och tillsatser. Basoljor är huvudsakligen kolväteföreningar medan tillsatser är olika kemiska föreningar som läggs till basoljan för att förbättra några av de befintliga egenskaperna eller att införa nya egenskaper som är fördelaktiga för applikationsändamål. Under lagringsperioden, där olika lagringsförhållanden kan uppstå, måste många av kraven på smörjmedlens kemiska och fysikaliska stabilitet uppfyllas. Olämpliga lagringsförhållanden kan orsaka fysiska och kemiska förändringar i smörjmedlen som kan göra dem oanvändbara för avsedd användning. Effekterna av olika lagringsförhållanden på smörjmedelstabilitet undersöktes i detta arbete. Experimentell del av detta projekt genomfördes hos Fuchs Lubricants Sweden AB. I början av experimentet, tolv 2L högdensitetspolyetenflaskor (HDPE) fyllda med smörjmedlet, uppdelades i tre grupper. Den första gruppen bestod av fyra slutna HDPE-flaskor som ifylldes med smörjmedlet och som lagrades vid 9 ° C, 22 ° C, 45 ° C och 80 ° C. Den andra och den tredje gruppen bestod också av fyra öppna flaskor och fyra flaskor med tillsatt destillerat vatten lagrat vid samma lagringstemperaturer. Mängden av smörjmedel var ungefär lika i alla flaskor. Vid olika tidpunkter togs prov från topp-mitten-och bottenskiktet från dessa flaskor och analyserades. Effekterna av olika lagringsförhållanden för smörjmedelsstabiliteten och homogeniteten förvärvades genom två distinkta spektroskopiska metoder. Induktivt kopplad plasma atomemissions-spektroskopi (ICP-AES) användes för elementsammansättningsanalys medan Fourier transform infraröd spektroskopi (FTIR) användes för utvärdering av kemiska förändringar på molekylär nivå. Resultat från ICP-AES-analyser visade nästan homogen fördelning av element, opåverkad av olika lagringsförhållanden i alla provflaskor. Resultat från FTIR-analyser visade att observerade förändringar i absorptionstoppar (673, 863, 972 och 1267 cm-1) inträffade nästan samtidigt i alla tre skikten i flaskorna lagrade vid fyra olika temperaturer. Dessa resultat tyder på att det analyserade smörjmedlet var stabilt och homogent under den observerade perioden. Den lägsta lagringstemperaturen orsakade minimala förändringar i smörjmedlet och kan betraktas som den optimala lagringstemperaturen för denna produkt. Resultatet visade också att ökad temperatur, direkt exponering för syre och närvaro av vatten hade katalytiskt påverkat graden av dessa förändringar. En del av detta projekt var att validera metoden som används för ICP-analys. För detta ändamål undersöktes följande metodprestanda-parametrar: linjäritet, precision, noggrannhet, detektionsgräns (LOD) och kvantifieringsgräns (LOQ). De erhållna resultaten visade att linjäriteten för metoden, för alla element, i den använda standarden bekräftades baserat på uppsatta kriterier. Precision och noggrannhet testades i repeterbarhetsförhållanden och vid fyra olika koncentrationsnivåer. De erhållna resultaten visade att metodens noggrannhet ökade med koncentration och var högst för 50 ppm, för nästan alla element. Den högsta precisionen (&lt;2% RSD), för nästan alla element, erhölls för koncentrationen av 25 ppm. LOD-värdena var mellan 0.01 och 1.42 ppm medan beräknade LOQ-värden var mellan 0.04 och 4.73 ppm.

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