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Untersuchungen zum Effekt von Glukose, Glukosedegradationsprodukten und alternativen osmotischen Agenzien in Peritonealdialyselösungen auf Vitalität und Synthesefunktion peritonealer MesothelzellenBender, Thorsten Onno 07 April 2005 (has links)
Konventionelle hitzesterilisierte, glukosehaltige Peritonealdialyselösungen (PDL) sind aufgrund ihres niedrigen pH-Wertes, ihrer hohen Glukosekonzentration und Osmolalität und ihres Gehaltes an Glukosedegradationsprodukten (GDP) bioinkompatibel. Alternativen zu glukosehaltigen PDL stellen aminosäuren- oder icodextrinhaltige PDL dar. Daneben enthalten auch neuere Glukose-PDL in Doppelkammersystemen aufgrund der Sterilisation von Glukose bei sehr niedrigem pH nur noch sehr geringe GDP-Konzentrationen. In dieser Arbeit wurden die akuten und chronischen Wirkungen verschiedener PDL auf humane peritoneale Mesothelzellen (HPMC) untersucht. Konfluente HPMC wurden mit den zu testenden PDL (glukosehaltige hitze- versus filtersterilisierte und konventionelle versus Doppelkammer-Glukose-PDL, 1% Aminosäuren-PDL und Icodextrin - alle bei neutralem pH-Wert) akut (1-4 Stunden Präinkubation) bzw. chronisch (bis zu 10 Tage) inkubiert. Die Zellvitalität (MTT-Assay) und IL-1beta-stimulierte Sekretion von IL-6 (Zellfunktion) wurden untersucht. Die akute und chronische Exposition von HPMC gegenüber hitzesteriliserten Peritonealdialyselösungen führte zu einer signifkanten Reduktion von Vitalität und Funktion der Zellen. Demgegenüber führte die Inkubation mit filtersteriliserten PDL und GDP-armen PDL zu einer weniger starken Beeinflussung von Vitalität und Funktion. Die aminosäurenhaltige PDL beeinflusste weder akut noch chronisch die Vitalität bzw. Funktion der Zellen negativ. Hingegen unterschied sich die icodextrinhaltige Lösung nicht wesentlich von der hitzesteriliserten PDL mit hohem Glukoseanteil. Die Verringerung des Gehaltes an GDP in PDL mittels Filtersterilisation bzw. alternativer Sterilisation in Zweikammerbeuteln hat einen positiven Einfluss auf Vitalität und Funktion von HPMC in vitro. Der Ersatz des osmotischen Agenz hingegen bedeutet nicht zwansgläufig eine bessere Biokompatibilität. / Conventional heat-sterilized glucose-containing peritoneal dialysis fluids (PDF) are bioincompatible due to their acidic pH, high glucose concentration and resulting hyperosmolality, and the presence of glucose degradation products (GDP). Alternatives to these solutions are PDL containing amino acids or icodextrin as the osmotic agent. Furthermore, novel glucose-based PDF contain only trace amounts of GDPs due to the sterilisation of glucose at very low pH in a dual-chamber container system. The present study examines the acute and chronic effects of different PDL on human peritoneal mesothelial cells (HPMC). Confluent HPMC were exposed to the different test PDF (glucose containing heat- versus filter-sterilised PDF and conventional versus dual-chambered glucose PDF, 1% amino-acid PDF and icodextrin – all at neutral pH) in an acute (1-4 hours preincubation) and chronic (up to 10 days) cell culture model. Cell viability (MTT assay) and IL-1beta stimulated IL-6 (cell function) release were assessed. Acute and chronic exposure of HPMC to heat-sterilised PDF resulted in a significant reduction of viability and cell function. In contrast, the incubation of filter-sterilised PDF and dual chambered low GDP solution had only minor effects on cell viability and function. Neither viability nor cell function were negatively affected by the amino-acid PDF following acute and chronic exposure. However, incubation with icodextrin resulted in a similar degree of inhibition as compared to incubation with conventional heat-sterilised glucose PDF. In conclusion, removal of GDP from PDF either via filter-sterilisation or manufacture in dual chambered containers helps to conserve viability and function of HPMC in vitro. However, the replacement of the osmotic agent per se does not necessarily result in improved biocompatibility.
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Biokompatibilita peritoneálních dialyzačních roztoků / Biocompatibility of Peritoneal Dialysis SolutionsProcházková Pöpperlová, Anna January 2016 (has links)
Peritoneal dialysis (PD) is a form of renal replacement therapy using the peritoneum as a dialysis membrane. PD solutions employed to remove nitrogen metabolites and excess plasma fluid, and to restore electrolyte and acid-base balance are being developed to minimize local and systemic inflammatory responses while maintaining peritoneal homeostasis and host defense. The effect of chronic action of PD solutions on the peritoneum results in its remodeling and, possibly, eventual loss of peritoneal ultrafiltration capacity. Factors most responsible for late complications and peritoneal remodeling include high glucose levels in PD solutions, and the presence and formation of glucose degradation products (GDP) and advanced glycation end - products (AGEs) in the peritoneal cavity. The aim of our study described in this dissertation was to test various PD solutions with different glucose content and GDP and, using AGEs receptor ligands, to define their systemic effects and identify PD solutions with highest biocompatibility. This part of the dissertation characterizes conventional glucose - based solutions, low - glucose and GDP load solutions as well as glucose polymer (icodextrin) - based PD solutions while determining the plasma and dialysate levels of soluble receptor for AGEs (s - RAGE) and its...
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Transport and degradation of pesticides in wetland systems : a downscaling approach / Transport et dégradation de pesticides en zones humides : une approche multi-échellesMaillard, Elodie 14 March 2014 (has links)
La compréhension des mécanismes de transport et de dégradation des pesticides émergents est primordiale pour prédire leur devenir dans l’environnement. Les zones humides peuvent intercepter des eaux de ruissellement ou des souterraines contaminées par les pesticides et les traiter par le biais de processus de rétention et de dégradation, encore peu connus. Dans une approche multi-échelles, trois zones humides recevant des eaux polluées par les pesticides ont été utilisées comme des « laboratoires naturels » pour étudier le devenir de pesticides couramment utilisés. Cette thèse souligne l’influence des conditions hydrologiques et redox sur la distribution des pesticides au sein des différents compartiments des zones humides ainsi que sur leur potentiel de dégradation. Alors que les études à grande échelle fournissent des informations intégratives sur la dissipation et la rétention des pesticides en lien avec le développement de la végétation, les études à petite échelle utilisant des techniques innovantes telles que les analyses isotopiques et énantiomériques permettent l’exploration des processus moléculaires de dégradation des pesticides. / A mechanistic understanding of transport and degradation processes of modern agricultural pesticides, including chiral pesticides, is critical for predicting their fate in the environment. In agricultural landscapes, wetlands can intercept pesticide-contaminated runoff or groundwater and improve water quality through various retention and degradation processes, which remain unknown. In a downscaling approach, three different wetlands receiving agricultural runoff were used as ‘natural laboratories’ to investigate the fate of widely used pesticides. Overall, our results showed that dynamics of hydrological and redox conditions largely influenced pesticide sorption mechanisms and their distribution over time within wetland compartments, thereby controlling degradation processes. While large-scale studies provide integrative information on pesticide dissipation and distribution patterns with respect to wetland functioning, small-scale investigations using novel methods such as isotope and enantiomer analyses characterize underlying molecular processes governing pesticide degradation.
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Mesilato de gemifloxacino : desenvolvimento e validação de métodos analíticos, teste de dissolução e estudo de estabilidadePaim, Clésio Soldateli January 2012 (has links)
A análise de fármacos é fundamental nas diversas fases do desenvolvimento farmacêutico, tais como em estudos de formulação, estabilidade e controle de qualidade do produto. O mesilato de gemifloxacino (MGF), liberado para uso clínico no Brasil em novembro de 2006 com o nome comercial de Factive®, é uma fluorquinolona indicada para o tratamento da exacerbação aguda da bronquite crônica e da pneumonia adquirida da comunidade. A literatura pesquisada apresenta poucos relatos de determinação quantitativa e de estudos de estabilidade do fármaco em comprimidos revestidos. Anteriormente aos estudos, foi realizada a caracterização da substância química de referência (SQR) de MGF por espectrofotometria no infravermelho (E IV), ressonância magnética nuclear de hidrogênio (RMN 1H) e carbono (RMN 13C), análise térmica por calorimetria exploratória de varredura (DSC) e determinação da faixa de fusão. Métodos analíticos para determinação qualitativa e quantitativa foram desenvolvidos e validados por espectrofotometria na região do ultravioleta (E UV) e visível (E VIS), cromatografia líquida de alta eficiência (CLAE), eletroforese capilar (EC) e ensaio microbiológico pelo método de cilindros em placas. A validação de um método de dissolução baseado em dados in vivo do fármaco também foi realizada. A elucidação do produto de degradação isolado em condições alcalinas foi realizada por E IV, RMN de 1H, 13C e correlação (COSY, HSQC e HMBC), espectrometria de massas (EM) e emissão atômica. Estudos de citotoxicidade, fototoxicidade, genotoxicidade e fotogenotoxicidade foram empregados para conhecimento da toxicidade dos produtos analisados. / The drug analysis is essential in all areas of the pharmaceutical development, such as during formulation studies, stability and quality control of the product. Gemifloxacin mesylate (GFM), approved for clinical use in Brazil in November of 2007 with the commercial name of Factive®, is a fluoroquinolone prescribed for the treatment of acute exacerbations of chronic bronchitis and community-acquired pneumonia. The research literature shows a few studies of quantitative determination and stabilities studies of the drug in coated tablets. Previously, it was performed the characterization of the reference chemical substance of GFM by infrared spectrometry (IR), nuclear magnetic resonance of 1H (1H NMR) and 13C (13C NMR), thermal analysis by differential scanning calorimetry (DSC) and determination of the melting range. Analytical methods for qualitative and quantitative determination were developed and validated by ultraviolet (UV) and visible (Vis) spectrophotometry, highperformance liquid chromatography (HPLC), capillary electrophoresis (CE) and microbiological assay applying the cylinder–plate method. The validation of the dissolution method based on in vivo data of the GFM was also performed. The elucidation of the isolate degradation product in alkaline conditions was performed by IR, 1H, 13C and correlation (COSY, HSQC and HMBC) NMR, and mass spectrometry (MS). Cytotoxicity, phototoxicity, genotoxicity and photogenotoxicity studies were carried out for the toxicity knowledge of the analyzed products.
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Mesilato de gemifloxacino : desenvolvimento e validação de métodos analíticos, teste de dissolução e estudo de estabilidadePaim, Clésio Soldateli January 2012 (has links)
A análise de fármacos é fundamental nas diversas fases do desenvolvimento farmacêutico, tais como em estudos de formulação, estabilidade e controle de qualidade do produto. O mesilato de gemifloxacino (MGF), liberado para uso clínico no Brasil em novembro de 2006 com o nome comercial de Factive®, é uma fluorquinolona indicada para o tratamento da exacerbação aguda da bronquite crônica e da pneumonia adquirida da comunidade. A literatura pesquisada apresenta poucos relatos de determinação quantitativa e de estudos de estabilidade do fármaco em comprimidos revestidos. Anteriormente aos estudos, foi realizada a caracterização da substância química de referência (SQR) de MGF por espectrofotometria no infravermelho (E IV), ressonância magnética nuclear de hidrogênio (RMN 1H) e carbono (RMN 13C), análise térmica por calorimetria exploratória de varredura (DSC) e determinação da faixa de fusão. Métodos analíticos para determinação qualitativa e quantitativa foram desenvolvidos e validados por espectrofotometria na região do ultravioleta (E UV) e visível (E VIS), cromatografia líquida de alta eficiência (CLAE), eletroforese capilar (EC) e ensaio microbiológico pelo método de cilindros em placas. A validação de um método de dissolução baseado em dados in vivo do fármaco também foi realizada. A elucidação do produto de degradação isolado em condições alcalinas foi realizada por E IV, RMN de 1H, 13C e correlação (COSY, HSQC e HMBC), espectrometria de massas (EM) e emissão atômica. Estudos de citotoxicidade, fototoxicidade, genotoxicidade e fotogenotoxicidade foram empregados para conhecimento da toxicidade dos produtos analisados. / The drug analysis is essential in all areas of the pharmaceutical development, such as during formulation studies, stability and quality control of the product. Gemifloxacin mesylate (GFM), approved for clinical use in Brazil in November of 2007 with the commercial name of Factive®, is a fluoroquinolone prescribed for the treatment of acute exacerbations of chronic bronchitis and community-acquired pneumonia. The research literature shows a few studies of quantitative determination and stabilities studies of the drug in coated tablets. Previously, it was performed the characterization of the reference chemical substance of GFM by infrared spectrometry (IR), nuclear magnetic resonance of 1H (1H NMR) and 13C (13C NMR), thermal analysis by differential scanning calorimetry (DSC) and determination of the melting range. Analytical methods for qualitative and quantitative determination were developed and validated by ultraviolet (UV) and visible (Vis) spectrophotometry, highperformance liquid chromatography (HPLC), capillary electrophoresis (CE) and microbiological assay applying the cylinder–plate method. The validation of the dissolution method based on in vivo data of the GFM was also performed. The elucidation of the isolate degradation product in alkaline conditions was performed by IR, 1H, 13C and correlation (COSY, HSQC and HMBC) NMR, and mass spectrometry (MS). Cytotoxicity, phototoxicity, genotoxicity and photogenotoxicity studies were carried out for the toxicity knowledge of the analyzed products.
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Mesilato de gemifloxacino : desenvolvimento e validação de métodos analíticos, teste de dissolução e estudo de estabilidadePaim, Clésio Soldateli January 2012 (has links)
A análise de fármacos é fundamental nas diversas fases do desenvolvimento farmacêutico, tais como em estudos de formulação, estabilidade e controle de qualidade do produto. O mesilato de gemifloxacino (MGF), liberado para uso clínico no Brasil em novembro de 2006 com o nome comercial de Factive®, é uma fluorquinolona indicada para o tratamento da exacerbação aguda da bronquite crônica e da pneumonia adquirida da comunidade. A literatura pesquisada apresenta poucos relatos de determinação quantitativa e de estudos de estabilidade do fármaco em comprimidos revestidos. Anteriormente aos estudos, foi realizada a caracterização da substância química de referência (SQR) de MGF por espectrofotometria no infravermelho (E IV), ressonância magnética nuclear de hidrogênio (RMN 1H) e carbono (RMN 13C), análise térmica por calorimetria exploratória de varredura (DSC) e determinação da faixa de fusão. Métodos analíticos para determinação qualitativa e quantitativa foram desenvolvidos e validados por espectrofotometria na região do ultravioleta (E UV) e visível (E VIS), cromatografia líquida de alta eficiência (CLAE), eletroforese capilar (EC) e ensaio microbiológico pelo método de cilindros em placas. A validação de um método de dissolução baseado em dados in vivo do fármaco também foi realizada. A elucidação do produto de degradação isolado em condições alcalinas foi realizada por E IV, RMN de 1H, 13C e correlação (COSY, HSQC e HMBC), espectrometria de massas (EM) e emissão atômica. Estudos de citotoxicidade, fototoxicidade, genotoxicidade e fotogenotoxicidade foram empregados para conhecimento da toxicidade dos produtos analisados. / The drug analysis is essential in all areas of the pharmaceutical development, such as during formulation studies, stability and quality control of the product. Gemifloxacin mesylate (GFM), approved for clinical use in Brazil in November of 2007 with the commercial name of Factive®, is a fluoroquinolone prescribed for the treatment of acute exacerbations of chronic bronchitis and community-acquired pneumonia. The research literature shows a few studies of quantitative determination and stabilities studies of the drug in coated tablets. Previously, it was performed the characterization of the reference chemical substance of GFM by infrared spectrometry (IR), nuclear magnetic resonance of 1H (1H NMR) and 13C (13C NMR), thermal analysis by differential scanning calorimetry (DSC) and determination of the melting range. Analytical methods for qualitative and quantitative determination were developed and validated by ultraviolet (UV) and visible (Vis) spectrophotometry, highperformance liquid chromatography (HPLC), capillary electrophoresis (CE) and microbiological assay applying the cylinder–plate method. The validation of the dissolution method based on in vivo data of the GFM was also performed. The elucidation of the isolate degradation product in alkaline conditions was performed by IR, 1H, 13C and correlation (COSY, HSQC and HMBC) NMR, and mass spectrometry (MS). Cytotoxicity, phototoxicity, genotoxicity and photogenotoxicity studies were carried out for the toxicity knowledge of the analyzed products.
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Βeta-bloqueadores em efluente hospitalar: ocorrência, degradação por processos avançados de oxidação e identificação de subprodutos / Βeta-blockers in hospital wastewater; occurence, degradation by advanced oxidation process and byproducts identificationWilde, Marcelo Luís 15 December 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / β-Blockers are an important group of prescription drugs; as a consequence of the large and continuous use, they are commonly found in the environment.
This study assessed, preliminary, the inherent risk of the β-blockers Atenolol, Metoprolol and Propranolol, mostly used in the University Hospital of Santa Maria (HUSM), and showed that Propranolol has high Risk Quotient (RQ) of 0.56.
HPLC-FLD and SPE methodologies were developed and optimized with the aid of experimental design in order to analyze the occurrence of β-blockers in the HUSM sewage system. The average concentration for Atenolol, Metoprolol and Propranolol found for a week sampling were 2.45, 4.67 and 0.70 μg L-1 in the sewage of the Emergence; 0.95, 0.70 and 0.315 μg L-1 in the HUSM main sewage, and 1.26, 1.27 and 0.56 μg L-1 in the water course receptor, respectively,
As possible remediation methodologies for the Hospital Wastewater (HWW) were investigated Advanced Oxidation Process (AOPs) such as photo-Fenton, K2FeO4, Ozonation and O3/Fe2+. The operational parameters were optimized by Response Surface Methodology (RSM). Using optimized conditions for photo-Fenton, Atenolol, Metoprolol and Propranolol were totally degraded in 5 min in aqueous solution, and the mineralization achieved 80% after 120 min of treatment. In HWW, the β-blockers were also totally degraded, however, only 26.5% of the organic matter and 38.6% of the aromaticity were removed. The ready biodegradability and toxicity of the photo-Fenton s samples were estimated by official methods, which indicated an increase in the biodegradability and toxicity. This behavior may be correlated to the formation of degradation products (DPs), relatively, more toxic. The DPs were identified with aid of Liquid Chromatography tandem Mass Spectrometry (LC-MSn).
Other proposed degradation process was oxidation-coagulation using Fe(VI), which achieved above 90% degradation for Atenolol, Metoprolol and Propranolol in HWW, while only 17% COD and 60% aromaticity removal. In aqueous solution this process led to 71.7%, 24.7% and 96.5% degradation of Atenolol, Metoprolol and Propranolol, respectively. No mineralization was found, indicating the formation of DPs, identified by LC-MSn. The ready biodegradability of the post-process samples was tested and the results showed that the oxidation-coagulation with Fe(VI) increased the biodegradability.
The applicability of ozonation was evaluated varying the pH (3-11) for HWW and aqueous solution. More than 95% of the β-blockers were degraded independently of the initial pH, while above 50% of the aromaticity was removed. In aqueous solution the β-blockers were degraded in 10 min treatment and the identification of the DPs were carried out for process pH 5, 7 and 9. Catalytic ozonation (O3/Fe2+) was applied to HWW and a mineralization of 49% was achieved, with 77.9% aromaticity removal. The β-blockers were totally degraded.
Therefore, the present study represents a high qualified analytical information contribution concerning the occurrence of β-blockers in HWW. The studied AOPs/Fe(VI) processes demonstrated to be suitable to degrade Atenolol, Metoprolol and Propranolol. Moreover, high removal of organic matter and aromaticity were achieved by appling O3/Fe2+ process.
In many aspects, this work can be considered original, in especial, by regarding the application of Ferrate(VI) and Catalytic Ozonation to the degradation of β-blockers in HWW. / Os β-bloqueadores são uma importante classe de fármacos prescritos na terapia de doenças cardiovasculares e como consequência de seu grande e contínuo uso são comumente encontrados no meio ambiente.
O presente estudo avaliou preliminarmente o risco inerente dos β-bloqueadores mais usados no Hospital Universitário de Santa Maria (HUSM), Atenolol, Metoprolol e Propranolol, evidenciando que Propranolol apresentou maior risco inerente com Quociente de Risco teórico de 0,56 (risco médio).
Métodos HPLC-FLD e de clean-up/pré-concentração por SPE foram desenvolvidos e otimizados com auxílio de Metodologia de Superfície de Resposta (RSM) para avaliar a ocorrência de β-bloqueadores no sistema de esgotos do HUSM. A concentração ambiental mensurada para Atenolol, Metoprolol e Propranolol durante um ciclo semanal no ponto de lançamento Efluente PA foi 2,45; 4,67 e 0,70 μg L-1, no ponto HUSM principal 0,95; 0,70 e 0,32 μg L-1 e para o Córrego onde os efluentes são lançados de 1,26; 1,27 e 0,56 μg L-1, respectivamente.
Como metodologia de remediação da contaminação de β-bloqueadores em Efluente Hospitalar (EH) foram investigados os Processos Avançados de Oxidação (PAOs) Foto-Fenton, K2FeO4, Ozonização e O3/Fe2+. Os parâmetros operacionais foram otimizados por RSM. Usando as condições otimizadas para o processo Foto-Fenton, Atenolol, Metoprolol e Propranolol foram totalmente degradados em 120 min de tratamento, contudo somente 26,5 e 38,6% da carga orgânica e aromaticidade, respectivamente, foram removidos em EH. A pronta biodegradabilidade e toxicidade para amostras aquosas do processo Foto-Fenton foram analisadas por métodos oficiais e indicaram aumento na biodegradabilidade e toxicidade. Este comportamento esta relacionado à formação de Produtos de Degradação (PD) relativamente mais tóxicos. Os PDs foram identificados por Cromatografia Líquida acoplada a Espectrometria de Massas (LC-MSn).
Outro processo proposto foi oxidação-coagulação com Fe(VI) que alcançou degradação de Atenolol, Metoprolol e Propranolol acima de 90% em EH, enquanto apenas 17 e 60% da matéria orgânica e aromaticidade foram removidos, respectivamente. Em solução aquosa este processo conduziu a degradação de 71,7; 24,7 e 96,5% de Atenolol, Metoprolol e Propranolol, respectivamente. Nenhuma mineralização foi encontrada indicando a formação de PDs, identificados por LC-MSn. A pronta biodegradabilidade para as amostras aquosas pós-processo foram avaliadas e os resultados encontrados mostraram que houve aumento na biodegradabilidade.
A aplicabilidade de ozonização foi avaliada variando o pH de 3-11 em EH e solução aquosa. Mais de 95% dos β-bloqueadores foram degradados independente do pH inicial, enquanto mais de 50% da aromaticidade e 30% da matéria orgânica foram. Em solução aquosa todos os β-bloqueadores foram degradados em menos de 10 min e para os processos em pH 5, 7 e 9 foram identificados os PDs. O processo de O3/Fe2+ alcançou 49% de remoção de matéria orgânica, 77,9% de redução da aromaticidade e completa degradação de Atenolol, Metoprolol e Propranolol em EH.
Portanto, o presente estudo contribui com informação analítica qualificada sobre a ocorrência de β-bloqueadores em EH. Os processos de degradação estudados mostraram-se adequados para a degradação de Atenolol, Metoprolol e Propranolol. Ademais, a maior remoção de matéria orgânica e aromaticidade foram observadas para o processo de O3/Fe2+.
Em muitos aspectos, este trabalho pode ser considerado original, em especial sobre a aplicação de ferrato(VI) e ozonização catalítica para a degradação de β-bloqueadores em EH.
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Étude des facteurs de l'hémostase après thrombolyse par le rT-PA dans l'infractus cérébral aigu : corrélations cliniques et étiologiques / Haemostasis factors after rt-PA thrombolysis in acute cerebral infarctSun, Xuhong 15 September 2015 (has links)
L'étude systématique de l'hémostase post-thrombolytique a été peu étudiée. Chez 80 malades thrombolysés consécutifs, une étude prospective a comporté l'étude – aux heures 0, 2 et 24 – des facteurs de l'hémostase suivants: fibrinogène, plasminogène, PDF (produits de dégradation de la fibrine et du fibrinogène), D-dimères, alpha2-antiplasmine et facteur XIII, ainsi que l'hématocrite et la numération plaquettaire. Des calculs statistiques approfondis ont exploré les corrélations des variations des facteurs hémostatiques entre eux et avec 37 paramètres cliniques et étiologiques. Processus moléculaires post-thrombolytiques. Le rt-PA induit deux processus, indépendants statistiquement à la 2ème heure: d'une part une élévation des PDF et des D-dimères; d'autre part, une baisse du fibrinogène, corrélée à une baisse du plasminogène (r=0,48, p=0.01), de l'alpha2-antiplasmine (r=0.48, p =0.004) et du facteur XIII (r=0.44, p=0.01). La baisse du plasminogène est corrélée significativement avec celle de l'alpha2-antiplasmine (r=0.77, p<0.001), et du facteur XIII (r=0.47, p=0.02). La mise en jeu de facteurs anti-fibrinolytiques, qui n'avait jamais été décrite précédemment, peut jouer un rôle dans une limitation de la fibrinolyse et dans la rethrombose. Des corrélations sont notées entre la baisse précoce du plasminogène et l'étiologie cardioembolique (p=0.04), et un mauvais pronostic final (p=0.03), possiblement en rapport la thrombolyse intense de gros caillots. Les hématomes intra-cérébraux parenchymateux (HP) sont liés significativement à la baisse du fibrinogène (p=0.01) et à l'augmentation des PDF (p=0.01). Une baisse du fibrinogène au-dessous de 2g/L multiplie la probabilité de HP précoce par un facteur 12,82. Ainsi est confirmé le modèle d'une “coagulopathie précoce avec dégradation du fibrinogène”», prédictive de l'hématome, proposé par l'équipe lyonnaise de thrombolyse en 2004 / A systematic study of post-thrombolytic haemostasis has rarely been performed. In 80 consecutive patients, we have prospectively studied at hours 0, 2 and 24 the following parameters: fibrinogen, plasminogen, alpha2-antiplasmin, factor XIII, fibrin(ogen) Degradation Products (FDP), D-dimers, haematocrit and platelet count. Comprehensive statistical studies calculated correlations of the haemostatic values betwen themselves and with 38 etiological and clinical parameters. Molecular dynamics. Two changes between h0 and h2 were statistically independent: an increase in FDP and D-Dimers; a decrease in fibrinogen, plasminogen, alpha2-antiplasmin and factor XIII. At h2, the decrease in fibrinogen was significantly correlated with that of plasminogen (0.48, p = 0.01), alpha2-antiplasmin (0.48, p = 0.004), and factor XIII (0.44, p = 0.01). The decrease in plasminogen was significantly correlated with those of antifibrinolytic components, alpha2-antiplasmin (r=0.77, p<0.001) and factor XIII (0.47, p=0.02). To our knowledge, such an activation of antifibrinolytic components had not hitherto been mentioned. The h2 decrease of plasminogen was correlated with cardioembolic etiology (p=0.04) and final poor oucome (p=0.03), a fact possibly due to intense thrombolysis of large clots. Patients having early parenchymal hematomas (PH) showed h2 haemostasis disturbances: high FDP (p=0.01), and low fibrinogen (p=0.01). The decrease in fibrinogen less than 2g/L multiplies the odds of early PH by a factor 12.82. Thus, we confirm the model of an “early fibrinogen degradation coagulopathy” predictive of hematomas, which had been coined by the Lyon thrombolysis team in 2004
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Analýza látek uvolněných z kompozitního zubního materiálu / Analysis of substances released from composite dental materialFučík, Jan January 2021 (has links)
This master's thesis deals with a present problem of alternative dental fillings, which should replace amalgam fillings. Although there are health concerns about these alternative materials, especially resin composite fillings raise concerns, because they release potentionally harmful substances into the oral cavity. Accordingly even this medical device subjects various tests before releasing to the commercial market and one of these tests was carried out according to ČSN EN ISO 10993 and available scientific literature in the experimental part of this thesis. The amalgam controversy, substances used for manufacturing of resin dental fillings and analytical methods are described in the theoretical part of the thesis. In the experimental part of the thesis, 30 days long cumulative extraction experiments were carried out into various extraction mediums in order to assess suitability of new dental resin filling from ADM, a.s. by comparison with commercially available dental material from company GC EUROPE N.V. These samples were analysed by LC-MS and the amount of eluted substances from dental composites to extraction medium was quantified.
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Biokompatibilita peritoneálních dialyzačních roztoků / Biocompatibility of Peritoneal Dialysis SolutionsProcházková Pöpperlová, Anna January 2016 (has links)
Peritoneal dialysis (PD) is a form of renal replacement therapy using the peritoneum as a dialysis membrane. PD solutions employed to remove nitrogen metabolites and excess plasma fluid, and to restore electrolyte and acid-base balance are being developed to minimize local and systemic inflammatory responses while maintaining peritoneal homeostasis and host defense. The effect of chronic action of PD solutions on the peritoneum results in its remodeling and, possibly, eventual loss of peritoneal ultrafiltration capacity. Factors most responsible for late complications and peritoneal remodeling include high glucose levels in PD solutions, and the presence and formation of glucose degradation products (GDP) and advanced glycation end - products (AGEs) in the peritoneal cavity. The aim of our study described in this dissertation was to test various PD solutions with different glucose content and GDP and, using AGEs receptor ligands, to define their systemic effects and identify PD solutions with highest biocompatibility. This part of the dissertation characterizes conventional glucose - based solutions, low - glucose and GDP load solutions as well as glucose polymer (icodextrin) - based PD solutions while determining the plasma and dialysate levels of soluble receptor for AGEs (s - RAGE) and its...
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