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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.
181

Detection and outcome of mild traumatic brain injury in patients and sportsmen : persisting symptoms, disabilities and life satisfaction in relation to S-100B, NSE and cortisol

Stålnacke, Britt-Marie January 2004 (has links)
Traumatic brain injuries are common (hospitalization incidence: 250-300 per 100.000 inhabitants/year) and a great majority of these injuries (80-85%) are classified as mild traumatic brain injury (MTBI/concussion). Many patients with MTBI (20-80%) suffer from subsequent persistent and often disabling symptoms. In previous studies serum levels of biochemical markers of brain tissue damage (S-100B and neuron-specific enolase, NSE) have been propounded to serve as predictors of persisting symptoms.In the present studies serum concentrations of S-100B, NSE and cortisol in acute phase and post-concussion symptoms, post-traumatic stress-related symptoms, disabilities and life satisfaction one year after the trauma, were investigated in 88 patients (53 men and 35 women) with MTBI. Serum concentrations of S-100B and NSE were also assessed in elite players (n=54) of typical contact sports (ice-hockey and soccer), which are known to be high risk activities with respect to head injury. Basketball players (n=18) were used as a control group. A majority of patients with MTBI showed higher serum concentrations of S-100B, NSE and cortisol on admission compared with a second blood sample obtained about 7 hours later (p<0.001 for all analyses). Sequelae were common one year after the injury. Postconcussion symptoms were encountered in 45 % of the patients, stress-related symptoms in 17 % and disabilities in 48 %, but only 3 patients (4 %) were on sick-leave on follow-up due to the head trauma. There was a statistically significant negative correlation between the total score of life satisfaction and the total score of disability (r= -0.514, p<0.001). Symptoms on admission (dizziness, nausea) and S-100B were statistically significantly associated with disabilities (p<0.024, multiple logistic regression analysis). Nausea on admission was also statistically significantly associated with life satisfaction (p=0.004). A statistically significant association was found only for S-100B with early (0-1 week postinjury, p=0.008) and only for cortisol with late (more than 52 weeks post-injury, p=0.022) post-traumatic stress-related symptoms. Concentrations of S-100B after game were statistically significantly increased in comparison with the levels before game (soccer, p<0.001; ice-hockey, p<0.001; basketball (p<0.001). Concentrations of NSE were only raised after soccer play (p<0.001). Increases in S-100-B (post-game minus pre-game values) were correlated to the number of jumps in basketball play (r=0.706, p=0.002). For soccer, increases in S-100B were correlated to the number of headers (r=0.428, p=0.02) and to the number of acceleration/deceleration events other than heading (r=0.453, p=0.02). The findings provide support for the idea that injury of brain tissue is involved in the genesis of persisting disabilities and long-term changes of life satisfaction in MTBI. Since S-100B increases in serum were correlated to the number of headers and since soccer play also increased serum levels of NSE (in contrast to ice hockey and basketball), it seems that heading may have an impact on brain tissue. The studies have also shown that ordinary playing of the team sports in question (i.e. soccer, ice hockey and basketball) increases S-100B serum concentrations, which has to be taken into consideration when S-100B is used for the detection of injury of brain tissue in sportsmen with acute/overt head trauma during sport practice. An analysis of the biochemical markers of brain damage (in particular S-100B) may be an additional source of valuable information in the management of patients and sportsmen with MTBI. S-100B also seems to be promising for the prediction of impairments and disabilities after MTBI.
182

18F-markierte S100-Proteine als potentielle Radioliganden für die funktionelle Charakterisierung des Rezeptors für advanced glycation endproducts (RAGE) in vitro und in vivo

Hoppmann, Susan 06 October 2009 (has links) (PDF)
Die Interaktion von S100-Proteinen mit dem Rezeptor für advanced glycation endproducts (RAGE) wird als hoch relevant bei der Entstehung, Manifestation und Progression verschiedener entzündlicher Erkrankungen sowie bei der Tumorigenese gewertet. Das tiefergehende Verständnis der Interaktion von S100-Proteinen mit RAGE in vivo stellt eine wissenschaftliche Herausforderung dar und ist ein Ansatz für therapeutische Interventionen. Darüber hinaus stellen Untersuchungen zum Metabolismus von extrazellulär zirkulierenden S100-Proteinen in vivo einen vielversprechenden Forschungsansatz zur Analyse von S100-Protein-assoziierten Erkrankungen dar. Die einzigartigen Eigenschaften der Positronen-Emissions-Tomographie (PET) als nicht-invasives bildgebendes Verfahren erlauben die Darstellung und quantitative Erfassung biochemischer Prozesse mit der Möglichkeit zelluläre und molekulare Reaktionswege aufzuzeigen sowie in vivo-Mechanismen von Krankheiten im Kontext eines physiologischen Umfeldes darzulegen. Ziel der vorliegenden Arbeit war es, Fluor-18-markierte S100-Proteine (18F-S100) herzustellen, diese biochemisch, radiochemisch und radiopharmakologisch zu charakterisieren und deren Metabolismus und Interaktion mit RAGE in vivo mittels Kleintier-PET am Tiermodell zu untersuchen. Es wurden die mit RAGE interagierenden S100-Proteine S100A1, S100A12 und S100B in biologisch funktioneller Form hergestellt. Dazu wurden die entsprechenden S100-Gene in den prokaryotischen Expressionsvektor pGEX-6P-1 kloniert. Mit diesen Konstrukten wurden E. coli-Zellen transformiert, aus denen nachfolgend die S100-Proteine isoliert und gereinigt werden konnten. Es konnte eine Reinigung unter nativen, milden Bedingungen etabliert werden, die es ermöglichte, S100A1, S100A12 und S100B in biologisch aktiver Form und in hohen Reinheitsgraden (> 95%) für die nachfolgenden Experimente bereitzustellen. Diese S100-Proteine wurden über den 18F-tragenden Aktivester N-Succinimidyl-4-[18F]fluorbenzoesäure ([18F]SFB) radioaktiv markiert und charakterisiert. Dabei konnte sichergestellt werden, dass die 18F-S100-Proteine in vitro und in vivo stabil sind. Weiterhin konnte nachgewiesen werden, dass die radioaktive Markierung keine Beeinträchtigung auf die biologische Funktionalität der S100-Proteine hat. Dies wurde anhand von sRAGE-Bindungsuntersuchungen sowie Zell-Interaktionsuntersuchungen an konfluenten Endothelzellen (HAEC) und an zu Makrophagen differenzierten THP-1-Zellen (THP-1-Makrophagen) verifiziert. Für die Untersuchung der RAGE-Bindung war die Produktion des löslichen sRAGE bzw. die Generation von flRAGE-berexprimierenden Zellen erforderlich. Beide Konstrukte wurden in geeigneten Zellsystemen exprimiert und das sRAGE-Protein wurde in biologisch aktiver Form synthetisiert und gereinigt (Reinheitsgrad > 97%). Die 18F-S100-Bindung an THP-1-Makrophagen und HAEC wurde in Gegenwart von glykierten LDL (glykLDL) sowie sRAGE signifikant inhibiert, was auf eine RAGE-Interaktion hinweist. Weiterhin konnten durch den Einsatz von Scavenger-Rezeptor-Liganden, wie z. B. Maleinanhydrid-modifiziertes BSA (malBSA) bzw. von Lektinen inhibierende Effekte erzielt werden. Dies ist ein Indiz für die 18F-S100-Interaktion mit Scavenger-Rezeptoren und Glykokonjugaten an der Zelloberfläche. Durch die Untersuchungen mittels konfokaler Laserscanning-Mikroskopie an THP-1-Makrophagen wurde eine Zellaufnahme des Fluoreszein-markierten S100A12 festgestellt. Weiterhin konnten Kolokalisationen mit Lektinen detektiert werden. Das metabolische Schicksal extrazellulär zirkulierender 18F-S100-Proteine in vivo wurde mit Hilfe dynamischer PET-Untersuchungen bzw. anhand von Bioverteilungs-Untersuchungen in männlichen Wistar-Ratten analysiert. Die Hauptakkumulation der Radioaktivität wurde in der Leber und in den Nieren detektiert. In diesen Organen findet der Metabolismus bzw. die glomeruläre Filtration der 18F-S100-Proteine statt. In den Untersuchungen zur Genexpression mittels Echtzeit-PCR sowie im immunchemischen Proteinnachweis am Western Blot wurde eine hohe Expression und Proteinbiosynthese des RAGE in der Lunge ermittelt. Die Lunge eignet sich daher als „Referenz“-Organ für eine funktionelle in vivo-Charakterisierung von RAGE mit 18FS100-Proteinen. Bei den durchgeführten PET-Untersuchungen konnte eine temporäre 18F-S100-Interaktion mit dem Lungengewebe festgestellt werden. Die Retention des 18FS100A12 in der Lunge wurde in Gegenwart von sRAGE inhibiert. Dies ist ein Hinweis dafür, dass 18F-S100-Proteine auch in vivo an RAGE binden können. Die Radioaktivitäts-Akkumulation in den Organen Leber und Milz, die eine Vielzahl von sessilen Makrophagen aufweisen, wurde durch die Applikation von malBSA inhibiert. Dies ist ein Indiz dafür, dass 18F-S100-Proteine in vivo mit Scavenger-Rezeptoren interagieren können. Die vorliegende Arbeit liefert deutliche Hinweise darauf, dass RAGE nicht der alleinige Rezeptor für 18F-S100-Proteine ist. Der Einsatz von 18F-S100-Proteinen als experimentelles Werkzeug in dynamischen PET-Untersuchungen birgt das Potential einer Charakterisierung von S100-Protein-assoziierten, pathophysiologischen Prozessen. / Members of the S100 family of EF-hand calcium binding proteins play important regulatory roles not only within cells but also exert effects in a cytokine-like manner on definite target cells once released into extracellular space or circulating blood. Accordingly, increased levels of S100 proteins in the circulating blood have been associated with a number of disease states, e.g., diabetes, cancer, and various inflammatory disorders. As the best known target protein of extracellular S100 proteins, the receptor for advanced glycation endproducts (RAGE) is of significant importance. However, the role of extracellular S100 proteins during etiology, progression, and manifestation of inflammatory disorders still is poorly understood. One reason for this is the shortage of sensitive methods for direct assessment of the metabolic fate of circulating S100 proteins and, on the other hand, measurement of functional expression of extracellular targets of S100 proteins, e.g., RAGE in vivo. In this line, small animal PET provides a valuable tool for noninvasive imaging of physiological processes and interactions like plasma or vascular retention, tissue-specific receptor binding, accumulation or elimination in vivo. To address this question, human S100 proteins were cloned in the bacterial expression vector pGEX-6P-1, expressed in E. coli BL21, and purified by affinity chromatography and anion exchange chromatography. Purified S100A1, S100B and S100A12 proteins were then radiolabeled with the positron emitter fluorine-18 (18F) by N-succinimidyl-4-[18F]fluorobenzoate ([18F]SFB). Radiolabeling of S100 proteins resulted in radiochemical yields of 3-10% (corrected for decay) and effective specific radioactivities of 1 GBq/µmol, respectively. For investigations about RAGE binding soluble RAGE (sRAGE) was expressed and purified using pSecTag2B. A radioligand binding assay confirmed specific binding of 18F-S100A12, 18F-S100A1, and 18F-S100B to immobilized sRAGE, also showing an order of affinity with S100A12 > S100A1 > S100B. These results indicate that radioactive labelling of S100 proteins did not affect their overall affinity to RAGE. Cellular association studies in human THP-1 macrophages and human aortic endothelial cells (HAEC) showed specific binding of all 18F-S100 proteins to the non-internalizing RAGE as confirmed by inhibitory effects exerted either by other RAGE ligands, e.g., glycated LDL, or by soluble RAGE. Of interest, 18F-S100 proteins were also shown to interact with other putative binding sites, e.g. scavenger receptors as well as proteoglycans. In this line, uptake of 18F-S100 proteins in THP-1 and HAEC could be inhibited by various scavenger receptor ligands, in particular by maleylated BSA as well as by lectines (e.g. ConA and SBA). Confocal laser scanning microscopy analysis showed a major part of the fluoresceinated S100A12 bound to the surface of THP-1 macrophages. Beyond this, uptake of S100A12 could be determined indicating an interaction of S100A12 with both non-internalizing, e.g., RAGE, and internalizing receptors, e.g. scavenger receptors. By evaluation of the relative contribution of 18F-S100A12 association to RAGE-overexpressed CHO cells (using pIres2-AcGFP1), 18F-S100A12 showed a significantly higher association to CHO-RAGE cells compared with CHO-mock cells. Based on these findings and due to their crucial role in inflammatory disorders the metabolic fate of S100 proteins was further investigated in dynamic small animal Positron emission tomography (PET) studies as well as in biodistribution studies in Wistar rats in vivo. For interpretation of in vivo investigations in rats, expression of RAGE was analyzed by quantitative real time RT-PCR as well as western blotting in various organs. Lung tissue expressed the highest level of RAGE protein compared to the other tissues. PET studies in rats revealed a comparatively long mean residence time of circulating 18F-S100 proteins. A major contributor to this phenomenon seems to be a sustained temporary interaction with tissues overexpressing RAGE, e.g., the lung. On the other hand, renal clearance of 18F-S100 via glomerular filtration is a major elimination pathway. However, scavenger receptor-mediated pathways in the liver, the spleen and, to a minor extent, in the kidneys, also seem to contribute to the overall clearance. The presence of sRAGE revealed a decreased retention of 18F-S100A12 in the lung, indicating in vivo binding to RAGE. In vivo blocking studies using maleylated BSA demonstrated a strong inhibition of putative binding sites in rat tissues enriched in cells expressing scavenger receptors like liver and spleen. In conclusion, 18F-labeling of S100 proteins and the use of small animal PET provide a valuable tool to discriminate the kinetics and the metabolic fate of S100 proteins in vivo. Furthermore, the results strongly suggest an involvement of other putative receptors beside RAGE in distribution, tissue association and elimination of circulating proinflammatory S100 proteins. Moreover, the approach provides novel probes for imaging of functional expression of RAGE and scavenger receptors in peripheral inflammatory compartments.
183

18F-markierte S100-Proteine als potentielle Radioliganden für die funktionelle Charakterisierung des Rezeptors für advanced glycation endproducts (RAGE) in vitro und in vivo

Hoppmann, Susan 11 September 2009 (has links)
Die Interaktion von S100-Proteinen mit dem Rezeptor für advanced glycation endproducts (RAGE) wird als hoch relevant bei der Entstehung, Manifestation und Progression verschiedener entzündlicher Erkrankungen sowie bei der Tumorigenese gewertet. Das tiefergehende Verständnis der Interaktion von S100-Proteinen mit RAGE in vivo stellt eine wissenschaftliche Herausforderung dar und ist ein Ansatz für therapeutische Interventionen. Darüber hinaus stellen Untersuchungen zum Metabolismus von extrazellulär zirkulierenden S100-Proteinen in vivo einen vielversprechenden Forschungsansatz zur Analyse von S100-Protein-assoziierten Erkrankungen dar. Die einzigartigen Eigenschaften der Positronen-Emissions-Tomographie (PET) als nicht-invasives bildgebendes Verfahren erlauben die Darstellung und quantitative Erfassung biochemischer Prozesse mit der Möglichkeit zelluläre und molekulare Reaktionswege aufzuzeigen sowie in vivo-Mechanismen von Krankheiten im Kontext eines physiologischen Umfeldes darzulegen. Ziel der vorliegenden Arbeit war es, Fluor-18-markierte S100-Proteine (18F-S100) herzustellen, diese biochemisch, radiochemisch und radiopharmakologisch zu charakterisieren und deren Metabolismus und Interaktion mit RAGE in vivo mittels Kleintier-PET am Tiermodell zu untersuchen. Es wurden die mit RAGE interagierenden S100-Proteine S100A1, S100A12 und S100B in biologisch funktioneller Form hergestellt. Dazu wurden die entsprechenden S100-Gene in den prokaryotischen Expressionsvektor pGEX-6P-1 kloniert. Mit diesen Konstrukten wurden E. coli-Zellen transformiert, aus denen nachfolgend die S100-Proteine isoliert und gereinigt werden konnten. Es konnte eine Reinigung unter nativen, milden Bedingungen etabliert werden, die es ermöglichte, S100A1, S100A12 und S100B in biologisch aktiver Form und in hohen Reinheitsgraden (> 95%) für die nachfolgenden Experimente bereitzustellen. Diese S100-Proteine wurden über den 18F-tragenden Aktivester N-Succinimidyl-4-[18F]fluorbenzoesäure ([18F]SFB) radioaktiv markiert und charakterisiert. Dabei konnte sichergestellt werden, dass die 18F-S100-Proteine in vitro und in vivo stabil sind. Weiterhin konnte nachgewiesen werden, dass die radioaktive Markierung keine Beeinträchtigung auf die biologische Funktionalität der S100-Proteine hat. Dies wurde anhand von sRAGE-Bindungsuntersuchungen sowie Zell-Interaktionsuntersuchungen an konfluenten Endothelzellen (HAEC) und an zu Makrophagen differenzierten THP-1-Zellen (THP-1-Makrophagen) verifiziert. Für die Untersuchung der RAGE-Bindung war die Produktion des löslichen sRAGE bzw. die Generation von flRAGE-berexprimierenden Zellen erforderlich. Beide Konstrukte wurden in geeigneten Zellsystemen exprimiert und das sRAGE-Protein wurde in biologisch aktiver Form synthetisiert und gereinigt (Reinheitsgrad > 97%). Die 18F-S100-Bindung an THP-1-Makrophagen und HAEC wurde in Gegenwart von glykierten LDL (glykLDL) sowie sRAGE signifikant inhibiert, was auf eine RAGE-Interaktion hinweist. Weiterhin konnten durch den Einsatz von Scavenger-Rezeptor-Liganden, wie z. B. Maleinanhydrid-modifiziertes BSA (malBSA) bzw. von Lektinen inhibierende Effekte erzielt werden. Dies ist ein Indiz für die 18F-S100-Interaktion mit Scavenger-Rezeptoren und Glykokonjugaten an der Zelloberfläche. Durch die Untersuchungen mittels konfokaler Laserscanning-Mikroskopie an THP-1-Makrophagen wurde eine Zellaufnahme des Fluoreszein-markierten S100A12 festgestellt. Weiterhin konnten Kolokalisationen mit Lektinen detektiert werden. Das metabolische Schicksal extrazellulär zirkulierender 18F-S100-Proteine in vivo wurde mit Hilfe dynamischer PET-Untersuchungen bzw. anhand von Bioverteilungs-Untersuchungen in männlichen Wistar-Ratten analysiert. Die Hauptakkumulation der Radioaktivität wurde in der Leber und in den Nieren detektiert. In diesen Organen findet der Metabolismus bzw. die glomeruläre Filtration der 18F-S100-Proteine statt. In den Untersuchungen zur Genexpression mittels Echtzeit-PCR sowie im immunchemischen Proteinnachweis am Western Blot wurde eine hohe Expression und Proteinbiosynthese des RAGE in der Lunge ermittelt. Die Lunge eignet sich daher als „Referenz“-Organ für eine funktionelle in vivo-Charakterisierung von RAGE mit 18FS100-Proteinen. Bei den durchgeführten PET-Untersuchungen konnte eine temporäre 18F-S100-Interaktion mit dem Lungengewebe festgestellt werden. Die Retention des 18FS100A12 in der Lunge wurde in Gegenwart von sRAGE inhibiert. Dies ist ein Hinweis dafür, dass 18F-S100-Proteine auch in vivo an RAGE binden können. Die Radioaktivitäts-Akkumulation in den Organen Leber und Milz, die eine Vielzahl von sessilen Makrophagen aufweisen, wurde durch die Applikation von malBSA inhibiert. Dies ist ein Indiz dafür, dass 18F-S100-Proteine in vivo mit Scavenger-Rezeptoren interagieren können. Die vorliegende Arbeit liefert deutliche Hinweise darauf, dass RAGE nicht der alleinige Rezeptor für 18F-S100-Proteine ist. Der Einsatz von 18F-S100-Proteinen als experimentelles Werkzeug in dynamischen PET-Untersuchungen birgt das Potential einer Charakterisierung von S100-Protein-assoziierten, pathophysiologischen Prozessen. / Members of the S100 family of EF-hand calcium binding proteins play important regulatory roles not only within cells but also exert effects in a cytokine-like manner on definite target cells once released into extracellular space or circulating blood. Accordingly, increased levels of S100 proteins in the circulating blood have been associated with a number of disease states, e.g., diabetes, cancer, and various inflammatory disorders. As the best known target protein of extracellular S100 proteins, the receptor for advanced glycation endproducts (RAGE) is of significant importance. However, the role of extracellular S100 proteins during etiology, progression, and manifestation of inflammatory disorders still is poorly understood. One reason for this is the shortage of sensitive methods for direct assessment of the metabolic fate of circulating S100 proteins and, on the other hand, measurement of functional expression of extracellular targets of S100 proteins, e.g., RAGE in vivo. In this line, small animal PET provides a valuable tool for noninvasive imaging of physiological processes and interactions like plasma or vascular retention, tissue-specific receptor binding, accumulation or elimination in vivo. To address this question, human S100 proteins were cloned in the bacterial expression vector pGEX-6P-1, expressed in E. coli BL21, and purified by affinity chromatography and anion exchange chromatography. Purified S100A1, S100B and S100A12 proteins were then radiolabeled with the positron emitter fluorine-18 (18F) by N-succinimidyl-4-[18F]fluorobenzoate ([18F]SFB). Radiolabeling of S100 proteins resulted in radiochemical yields of 3-10% (corrected for decay) and effective specific radioactivities of 1 GBq/µmol, respectively. For investigations about RAGE binding soluble RAGE (sRAGE) was expressed and purified using pSecTag2B. A radioligand binding assay confirmed specific binding of 18F-S100A12, 18F-S100A1, and 18F-S100B to immobilized sRAGE, also showing an order of affinity with S100A12 > S100A1 > S100B. These results indicate that radioactive labelling of S100 proteins did not affect their overall affinity to RAGE. Cellular association studies in human THP-1 macrophages and human aortic endothelial cells (HAEC) showed specific binding of all 18F-S100 proteins to the non-internalizing RAGE as confirmed by inhibitory effects exerted either by other RAGE ligands, e.g., glycated LDL, or by soluble RAGE. Of interest, 18F-S100 proteins were also shown to interact with other putative binding sites, e.g. scavenger receptors as well as proteoglycans. In this line, uptake of 18F-S100 proteins in THP-1 and HAEC could be inhibited by various scavenger receptor ligands, in particular by maleylated BSA as well as by lectines (e.g. ConA and SBA). Confocal laser scanning microscopy analysis showed a major part of the fluoresceinated S100A12 bound to the surface of THP-1 macrophages. Beyond this, uptake of S100A12 could be determined indicating an interaction of S100A12 with both non-internalizing, e.g., RAGE, and internalizing receptors, e.g. scavenger receptors. By evaluation of the relative contribution of 18F-S100A12 association to RAGE-overexpressed CHO cells (using pIres2-AcGFP1), 18F-S100A12 showed a significantly higher association to CHO-RAGE cells compared with CHO-mock cells. Based on these findings and due to their crucial role in inflammatory disorders the metabolic fate of S100 proteins was further investigated in dynamic small animal Positron emission tomography (PET) studies as well as in biodistribution studies in Wistar rats in vivo. For interpretation of in vivo investigations in rats, expression of RAGE was analyzed by quantitative real time RT-PCR as well as western blotting in various organs. Lung tissue expressed the highest level of RAGE protein compared to the other tissues. PET studies in rats revealed a comparatively long mean residence time of circulating 18F-S100 proteins. A major contributor to this phenomenon seems to be a sustained temporary interaction with tissues overexpressing RAGE, e.g., the lung. On the other hand, renal clearance of 18F-S100 via glomerular filtration is a major elimination pathway. However, scavenger receptor-mediated pathways in the liver, the spleen and, to a minor extent, in the kidneys, also seem to contribute to the overall clearance. The presence of sRAGE revealed a decreased retention of 18F-S100A12 in the lung, indicating in vivo binding to RAGE. In vivo blocking studies using maleylated BSA demonstrated a strong inhibition of putative binding sites in rat tissues enriched in cells expressing scavenger receptors like liver and spleen. In conclusion, 18F-labeling of S100 proteins and the use of small animal PET provide a valuable tool to discriminate the kinetics and the metabolic fate of S100 proteins in vivo. Furthermore, the results strongly suggest an involvement of other putative receptors beside RAGE in distribution, tissue association and elimination of circulating proinflammatory S100 proteins. Moreover, the approach provides novel probes for imaging of functional expression of RAGE and scavenger receptors in peripheral inflammatory compartments.
184

Efeito neuroprotetor do transplante de células-tronco mesenquimais derivadas de dente decíduo humano em ratos Wistar submetidos à lesão medular

Nicola, Fabrício do Couto January 2017 (has links)
A lesão medular (LM) é uma patologia incapacitante que resulta em déficits sensoriais e motores. No Brasil, a incidência anual é de 30 novos casos de lesão medular a cada 1 milhão de indivíduos e, infelizmente, a LM permanece sem um tratamento eficaz. Células-tronco derivadas do dente decíduo humano estão entre as potenciais fontes de células-tronco para transplante após a lesão medular, cujo objetivo é de promover a proteção ou a recuperação da lesão na medula espinal. Buscou-se nesta tese avaliar os efeitos do transplante, uma hora após a lesão, das células tronco de dente decíduo humano (SHED) no período agudo, subagudo e crônico sobre a neuroproteção, proteção tecidual e recuperação funcional em ratos Wistar submetidos à lesão medular por contusão. Os principais objetivos foram: a) investigar os efeitos do transplante das SHED sobre a recuperação funcional, volume da lesão e morte neuronal; b) verificar os efeitos do transplante sobre as células progenitoras, formação da cicatriz glial e modificações astrocitárias após o modelo de contusão medular Observou-se a melhora na recuperação funcional, redução do volume da lesão e morte neuronal na medula espinal dos animais que receberam o transplante de SHED após a lesão medular. As SHED aumentam o número de células precursoras na medula espinal, no período subagudo, reduzem a expressão da proteína fibrilar glial ácida (GFAP) e aumentam a expressão do canal retificador de influxo de potássio 4.1, ambas proteínas astrocitárias. Concluímos que o transplante de células-tronco derivadas do dente decíduo humano após a lesão medular promove a recuperação funcional a partir do efeito neuroprotetor iniciado na fase aguda, confirmado pelo maior número de neurônios motores presentes seis semanas após a contusão. As SHED são capazes de aumentar o número de células precursoras e de produzir modificações astrocitárias na medula espinal de ratos lesados na fase subaguda, reduzindo a formação da cicatriz glial. / Spinal cord injury (SCI) is a disabling condition that results in sensory and motor deficits. The estimated annual incidence in Brazil is of 30 new cases of spinal cord injury per 1 million of individuals; unfortunately SCI remains without an effective treatment. Stem cells from human exfoliated deciduous teeth (SHED) are one among potential sources of stem cells for transplantation after spinal cord injury in order to promote protection or tissue and functional recovery after spinal cord injury. The aim of this Thesis was to evaluate the effects of stem cells from human exfoliated deciduous teeth (SHED) transplantation, one hour after lesion, in the acute, subacute and chronic phases on neuroprotection, tissue protection and functional recovery in Wistar rats submitted to spinal cord injury by contusion The main goals were: a) to investigate the effects of SHED transplantation on functional recovery, lesion volume, and neuronal death; b) to verify the effects of the transplantation on the progenitor cells number, glial scar formation and astrocytic modifications after spinal cord contusion. Improvement of functional recovery, reduction of lesion volume and neuronal death were observed in the spinal cord of animals submitted to spinal cord injury and SHED transplantation. SHEDs increased the number of precursor cells in the spinal cord in the subacute period, reduced the expression of glial fibrillary acidic protein (GFAP) and increased the expression of the potassium influx rectifier channel 4.1, both astrocyte proteins. We conclude that transplantation of stem cells from human exfoliated deciduous teeth after spinal cord injury promotes functional recovery from the neuroprotection effect, which starts in the acute phase and is confirmed six weeks after the contusion with a higher number of motor neurons in the ventral horn of spinal cord. SHEDs are able to increase the number of precursor cells and produce astrocyte modifications in the spinal cord of injured rats in the subacute phase, reducing glial scar formation.
185

Efeito neuroprotetor do transplante de células-tronco mesenquimais derivadas de dente decíduo humano em ratos Wistar submetidos à lesão medular

Nicola, Fabrício do Couto January 2017 (has links)
A lesão medular (LM) é uma patologia incapacitante que resulta em déficits sensoriais e motores. No Brasil, a incidência anual é de 30 novos casos de lesão medular a cada 1 milhão de indivíduos e, infelizmente, a LM permanece sem um tratamento eficaz. Células-tronco derivadas do dente decíduo humano estão entre as potenciais fontes de células-tronco para transplante após a lesão medular, cujo objetivo é de promover a proteção ou a recuperação da lesão na medula espinal. Buscou-se nesta tese avaliar os efeitos do transplante, uma hora após a lesão, das células tronco de dente decíduo humano (SHED) no período agudo, subagudo e crônico sobre a neuroproteção, proteção tecidual e recuperação funcional em ratos Wistar submetidos à lesão medular por contusão. Os principais objetivos foram: a) investigar os efeitos do transplante das SHED sobre a recuperação funcional, volume da lesão e morte neuronal; b) verificar os efeitos do transplante sobre as células progenitoras, formação da cicatriz glial e modificações astrocitárias após o modelo de contusão medular Observou-se a melhora na recuperação funcional, redução do volume da lesão e morte neuronal na medula espinal dos animais que receberam o transplante de SHED após a lesão medular. As SHED aumentam o número de células precursoras na medula espinal, no período subagudo, reduzem a expressão da proteína fibrilar glial ácida (GFAP) e aumentam a expressão do canal retificador de influxo de potássio 4.1, ambas proteínas astrocitárias. Concluímos que o transplante de células-tronco derivadas do dente decíduo humano após a lesão medular promove a recuperação funcional a partir do efeito neuroprotetor iniciado na fase aguda, confirmado pelo maior número de neurônios motores presentes seis semanas após a contusão. As SHED são capazes de aumentar o número de células precursoras e de produzir modificações astrocitárias na medula espinal de ratos lesados na fase subaguda, reduzindo a formação da cicatriz glial. / Spinal cord injury (SCI) is a disabling condition that results in sensory and motor deficits. The estimated annual incidence in Brazil is of 30 new cases of spinal cord injury per 1 million of individuals; unfortunately SCI remains without an effective treatment. Stem cells from human exfoliated deciduous teeth (SHED) are one among potential sources of stem cells for transplantation after spinal cord injury in order to promote protection or tissue and functional recovery after spinal cord injury. The aim of this Thesis was to evaluate the effects of stem cells from human exfoliated deciduous teeth (SHED) transplantation, one hour after lesion, in the acute, subacute and chronic phases on neuroprotection, tissue protection and functional recovery in Wistar rats submitted to spinal cord injury by contusion The main goals were: a) to investigate the effects of SHED transplantation on functional recovery, lesion volume, and neuronal death; b) to verify the effects of the transplantation on the progenitor cells number, glial scar formation and astrocytic modifications after spinal cord contusion. Improvement of functional recovery, reduction of lesion volume and neuronal death were observed in the spinal cord of animals submitted to spinal cord injury and SHED transplantation. SHEDs increased the number of precursor cells in the spinal cord in the subacute period, reduced the expression of glial fibrillary acidic protein (GFAP) and increased the expression of the potassium influx rectifier channel 4.1, both astrocyte proteins. We conclude that transplantation of stem cells from human exfoliated deciduous teeth after spinal cord injury promotes functional recovery from the neuroprotection effect, which starts in the acute phase and is confirmed six weeks after the contusion with a higher number of motor neurons in the ventral horn of spinal cord. SHEDs are able to increase the number of precursor cells and produce astrocyte modifications in the spinal cord of injured rats in the subacute phase, reducing glial scar formation.
186

Efeito neuroprotetor do transplante de células-tronco mesenquimais derivadas de dente decíduo humano em ratos Wistar submetidos à lesão medular

Nicola, Fabrício do Couto January 2017 (has links)
A lesão medular (LM) é uma patologia incapacitante que resulta em déficits sensoriais e motores. No Brasil, a incidência anual é de 30 novos casos de lesão medular a cada 1 milhão de indivíduos e, infelizmente, a LM permanece sem um tratamento eficaz. Células-tronco derivadas do dente decíduo humano estão entre as potenciais fontes de células-tronco para transplante após a lesão medular, cujo objetivo é de promover a proteção ou a recuperação da lesão na medula espinal. Buscou-se nesta tese avaliar os efeitos do transplante, uma hora após a lesão, das células tronco de dente decíduo humano (SHED) no período agudo, subagudo e crônico sobre a neuroproteção, proteção tecidual e recuperação funcional em ratos Wistar submetidos à lesão medular por contusão. Os principais objetivos foram: a) investigar os efeitos do transplante das SHED sobre a recuperação funcional, volume da lesão e morte neuronal; b) verificar os efeitos do transplante sobre as células progenitoras, formação da cicatriz glial e modificações astrocitárias após o modelo de contusão medular Observou-se a melhora na recuperação funcional, redução do volume da lesão e morte neuronal na medula espinal dos animais que receberam o transplante de SHED após a lesão medular. As SHED aumentam o número de células precursoras na medula espinal, no período subagudo, reduzem a expressão da proteína fibrilar glial ácida (GFAP) e aumentam a expressão do canal retificador de influxo de potássio 4.1, ambas proteínas astrocitárias. Concluímos que o transplante de células-tronco derivadas do dente decíduo humano após a lesão medular promove a recuperação funcional a partir do efeito neuroprotetor iniciado na fase aguda, confirmado pelo maior número de neurônios motores presentes seis semanas após a contusão. As SHED são capazes de aumentar o número de células precursoras e de produzir modificações astrocitárias na medula espinal de ratos lesados na fase subaguda, reduzindo a formação da cicatriz glial. / Spinal cord injury (SCI) is a disabling condition that results in sensory and motor deficits. The estimated annual incidence in Brazil is of 30 new cases of spinal cord injury per 1 million of individuals; unfortunately SCI remains without an effective treatment. Stem cells from human exfoliated deciduous teeth (SHED) are one among potential sources of stem cells for transplantation after spinal cord injury in order to promote protection or tissue and functional recovery after spinal cord injury. The aim of this Thesis was to evaluate the effects of stem cells from human exfoliated deciduous teeth (SHED) transplantation, one hour after lesion, in the acute, subacute and chronic phases on neuroprotection, tissue protection and functional recovery in Wistar rats submitted to spinal cord injury by contusion The main goals were: a) to investigate the effects of SHED transplantation on functional recovery, lesion volume, and neuronal death; b) to verify the effects of the transplantation on the progenitor cells number, glial scar formation and astrocytic modifications after spinal cord contusion. Improvement of functional recovery, reduction of lesion volume and neuronal death were observed in the spinal cord of animals submitted to spinal cord injury and SHED transplantation. SHEDs increased the number of precursor cells in the spinal cord in the subacute period, reduced the expression of glial fibrillary acidic protein (GFAP) and increased the expression of the potassium influx rectifier channel 4.1, both astrocyte proteins. We conclude that transplantation of stem cells from human exfoliated deciduous teeth after spinal cord injury promotes functional recovery from the neuroprotection effect, which starts in the acute phase and is confirmed six weeks after the contusion with a higher number of motor neurons in the ventral horn of spinal cord. SHEDs are able to increase the number of precursor cells and produce astrocyte modifications in the spinal cord of injured rats in the subacute phase, reducing glial scar formation.
187

Možnost zpracování glycerolové fáze z výroby bionafty / Possibilities of reprocessing of glycerol layer from the manufacture of bionaphta

Hýža, Bohumil January 2014 (has links)
The aim of this thesis was to introduce and apply the possibilities of using waste glycerol from biodiesel production and partly waste low-stiffen coolant from cars that could be applied in industry. At the beginning of the thesis is summarized biodiesel production and its world production. There is more developed biodiesel production in the Czech Republic and in the European Union and some European legal regulations and standards for biodiesel. Also described herein is a composition of biodiesel and the description of the technology of its production. In the theoretical section summarizes the physical and chemical properties of glycerol and there is also summarized the traditional use of glycerol as food, explosives, etc. There are also new procedures that were performed in the experimental part of the thesis. There are described the ion exchange mechanism, ion exchange resin properties and the properties of the acids and salts generated by neutralization with NaOH contained in the waste glycerol. Also is described herein the wood protection and properties of ethylene glycol coolants and properties of boroglycerol and boroglycol as protection for wood and mechanism of their preparation. Next is described the mechanism of dehydration of glycerol to acrolein and options which can perform the synthesis. In the experimental part, the pH of waste glycerol was measured, then was measured the exact amount of NaOH in the glycerol. There is also desribed cleaning of waste glycerol from NaOH using acidic cation exchange resins on columns, or by neutralization with oleic acid, lactic acid and CO2. Further syntheses were performed glycerol borate and ethylene glycol borate. Water amount in ethylene glycol and methanol with water amount in glycerol were found by distillation. Then were prepared boroglycol and boroglycerol. By the amount resulting from the amount of reaction water were observed reaction conditions H3BO3, Na2B4O7•10 H2O and glycerol. At the end was carried out experimental dilution resulting boroglycerol and boroglycol by ethanol, methanol, TMB. Finally, the diluted boroglycerol was deposited on wood. Dehydration of glycerol to acrolein under the catalytic action of KHSO4 was performed. The results are given all the results and discussed the possibility of using the knowledge gained in this work in the industry. In conclusion, there are listed the economic comparison using waste glycerol and crude oil as a raw material and also charts the development of oil prices in 40 years since 1970, and graph of the price of waste glycerol.
188

Možnosti zpracování odpadů glykolu a glycerolu na účelové látky / Possibilities of reprocessing of the glycol and glycerol waste into suitable materials

Hýža, Bohumil January 2014 (has links)
At the beginning of the thesis is summarized biodiesel production and its world production. There is more developed biodiesel production in the Czech Republic and in the European Union and some European legal regulations and standards for biodiesel. Also described herein is a composition of biodiesel and the description of the technology of its production. In the theoretical section summarizes the physical and chemical properties of glycerol and there is also summarized the traditional use of glycerol as food, explosives, etc. There are also new procedures that were performed in the experimental part of the thesis. Then, here are the proposed new procedures for processing waste glycerol and glycol, which were conducted in the experimental part of the thesis. There are described the ion exchange properties of the cation exchangers and also properties of salts generated by neutralization of NaOH in the waste glycerol with organic acids and CO2. There is also described wood protection, properties of ethylene glycol as coolant and properties of boroglycerols and boroglycols as protection for wood and mechanism of their preparation. Then there is described a mechanism of dehydration of glycerol to acrolein and options which can perform the synthesis. In the experimental part, the pH of waste glycerol was measured and then was measured the amount of NaOH in the waste glycerol. There is also desribed cleaning of waste glycerol from NaOH using acidic cation exchange resins on columns, or by neutralization with oleic acid, lactic acid and CO2. Further syntheses were performed glycerol borate and ethylene glycol borate. Water amount in ethylene glycol and methanol with water amount in glycerol were found by distillation. Then were prepared boroglycol and boroglycerol. By the amount resulting from the amount of reaction water were observed reaction conditions H3BO3, Na2B4O7•10 H2O and glycerol. At the end was carried out experimental dilution resulting boroglycerol and boroglycol by ethanol, methanol, TMB. Finally, the diluted boroglycerol was deposited on wood. Dehydration of glycerol to acrolein under the catalytic action of KHSO4 was performed. The results are given all the results and discussed the possibility of using the knowledge gained in this work in the industry. In conclusion, there are listed the economic comparison using waste glycerol and crude oil as a raw material and also charts the development of oil prices in 40 years since 1970, and graph of the price of waste glycerol. There is also discussed technological applicability of the methods used in practice.

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