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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.
291

Atividade antinociceptiva e anti-inflamatória de Piptadenia stipulacea (Benth.) Ducke (FABACEAE) e inibição de COX por galetina 3,6-dimetil éter (FGAL) / Antinociceptive and anti-inflammatory activities of Piptadenia stipulacea (Benth.) Ducke (FABACEAE) and inhibition of COX by galetin 3,6-dimethyl ether (FGAL)

Queiroz, Aline Cavalcanti de 03 March 2011 (has links)
Piptadenia stipulacea belongs to the Fabaceae family,and is widely distributed in the caatinga. This species is commonly known in the Brazilian Northeast as jurema-branca , carcará and rasga-beiço , and is used in folk medicine in inflammation.In this study, we attempted to identify the possible antinociceptive and anti-inflammatory activities of the aqueous phase, the ethyl acetate phase and one flavonoid obtained from aerial parts of Piptadenia stipulacea. Aerial parts of Piptadenia stipulaceawere used and after fractionation, the flavonoid Galetin 3,6-dimethyl ether(FGAL) was obtained of the chloroformic phase of this plant. Experiments were conducted on Swiss mice using the acetic acid-induced writhing test, the hot plate test, the formalin test and zymosan A-induced peritonitis test. To characterize the mechanism(s) responsible for these antinociceptive and anti-inflammatory actions of FGAL, COX inhibitor screening assay kit and test of DPPH was used. The aqueous and ethyl acetate phases (100 mg/kg, p.o.); and the flavonoid FGAL (100 μmol/kg, p.o. or i.p.), reduced the nociception produced by acetic acid, by 49,9 ± 11,2, 54,6 ± 5,3, 39,0 ± 6,8 and64,8% ± 8,1, respectively. As FGAL have greater antinociceptive activity when administered intraperitoneally compared to oral route, we chose this route you follow up the study with FGAL. The ethyl acetate phase (100 mg/kg, p.o.) reduced nociception in the hot plate, indicating that this fraction exhibited central activity. The ethyl acetate phase (100 mg/kg, p.o.) reduced the formalin effects in both phases by 40,2± 10,3 and59,9% ± 6,5, respectively. Treatment with the aqueous phase (100 mg/kg, p.o.) and FGAL (100_mol/kg, i.p.) only protected the second phase by 78,5± 5,5 and 64,0% ± 8,0, respectively. In addition, it was observed in the zymosan A-induced peritonitis test that the aqueous phase, the ethyl acetate phase and FGAL exhibited anti-inflammatory activity, reducing significantly the number of recruit cells by 35,8 ± 4,9, 37,7 ± 6,2 and 31,3% ± 13,3, respectively. Moreover, FGAL at 0,2μM was able to inhibit COX-1 (79,5% ± 0,6) and COX-2 (56,0% ± 3,8), with an inhibition profile similar to indomethacin in the same concentration (93.0 ±2.6and79.0±1.5%, respectively), showinginhibitionofCOX-1 in greaterproportionthanCOX-2. Furthermore, indomethacin was more effective, both COX-1 andCOX-2 when compared to FGAL. In the test of DPPH, FGAL showed high radical scavenging activity. These results infer that the aqueous phase, the ethyl acetate phase and FGAL obtained from aerial parts of Piptadeniastipulacea are able to modulate the peripheral nociception and acute inflammatory response. TheflavonoidFGALinhibitCOX-1 andCOX-2, probably for its ability to scavenge free radicals, this being one of its mechanism of action in nociception and inflammation. Moreover, the results corroborate the popular use of Piptadenia stipulacea by their anti-inflammatory property. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Piptadenia stipulacea,pertence à família Fabaceae, é amplamente distribuída na caatinga. Esta espécie é conhecida no Nordeste brasileiro como jurema-branca, carcará e rasga-beiço, sendo utilizada na medicina popular para tratar inflamação. Neste trabalho, buscou-se investigar a atividade antinociceptiva e anti-inflamatória da fase aquosa, fase acetato de etila e de um flavonoide isolado das partes aéreas de Piptadenia stipulacea. As partes aéreas de Piptadenia stipulacea foram usadas para o fracionamento e, posteriormente o flavonóide galetina 3,6-dimetil éter(FGAL)foi obtido da fase clorofórmica da planta. Experimentos foram realizados em camundongos Swiss usando o modelo de contorções abdominais induzidas por ácido acético, ensaio da placa quente, teste de formalina e peritonite induzida por zymosan A. Para caracterizar o mecanismo de ação de FGAL responsável por sua ação antinociceptiva, o ensaio de inibição de cicloxigenase (COX) in vitro e a análise da atividade sequestrante radicalar através do método fotocolorimétrico de consumo de 2,2-difenil-1-picrihidrazila(DPPH) foram utilizados. As fases aquosa e acetato de etila(100 mg/kg, v.o.); e o flavonoide FGAL (100 μmol/kg, v.o. ou i.p.) reduziram a nocicepção produzida por ácido acético, na proporção de 49,9 ± 11,2, 54,6 ± 5,3, 39,0 ± 6,8 e 64,8% ± 8,1, respectivamente.Por FGAL apresentar maior atividade antinociceptiva ao ser administrado pela via intraperitoneal quando comparado com a via oral, escolheu-se essa via para dar sequência ao estudo com FGAL. Posteriormente, verificou-se também a inibição da nocicepção no ensaio de placa quente através do tratamento com a fase acetato de etila (v.o., 100 mg/kg), indicando que esta fase apresenta atividade central. A fase acetato de etila (v.o., 100 mg/kg) reduziu a nocicepção gerada pela aplicação de formalina em ambas as fases do teste, apresentando porcentagem de inibição de 40,2 ± 10,3e 59,9% ± 6,5, respectivamente. O tratamento com a fase aquosa (100 mg/kg, v.o.) e FGAL (100 μmol/kg, i.p.) apenas se mostraram ativos na segunda fase do teste de formalina na proporção de 72,6± 5,5 e 66,0% ± 8,0, respectivamente. Além disso, as fases aquosa (100 mg/kg, v.o.), acetato deetila (100 mg/kg, v.o.) e FGAL (100 μmol/kg, i.p.) tambémapresentaram efeito anti-inflamatório significante quando comparadas ao grupo controle, apresentando porcentagem de inibição de recrutamento celular na peritonite induzida por zymosan A de 35,8 ± 4,9, 37,7 ± 6,2 e 31,3% ± 13,3, respectivamente.FGAL, na concentração de 0,2 μM inibiu COX-1 (79,5% ± 0,6) e COX-2 (56,0% ± 3,8), com um perfil de inibição similar ao observado para indometacina na mesma concentração (93,0 ± 2,6 e 79,0% ± 1,5, respectivamente), apresentando inibição de COX-1 em maior proporção do que COX-2. Além disso, indometacina inibiu de forma mais eficaz, tanto COX-1 como COX-2 quando comparado a FGAL. No teste de2,2-difenil-1-picriidrazila(DPPH), FGAL, na concentração de 0,3 mM, mostrou alta atividade sequestrante radicalar. Estes resultados inferem que a fase aquosa, a fase acetato e FGAL obtidos das partes aéreas de Piptadenia stipulacea são capazes de modular a antinocicepção e a resposta inflamatória aguda.O flavonoide FGAL inibe COX-1 e COX-2, provavelmente por sua capacidade de sequestrar radicais livres, sendo este um dos seus mecanismos de ação na nocicepção e inflamação. Além disso, os resultados encontrados corroboram com o uso popular de Piptadenia stipulacea por suas propriedade anti-inflamatória.
292

Um modelo quantitativo para o valor do cliente

Ferreira, Eduardo Carlos 17 July 2007 (has links)
Made available in DSpace on 2010-04-20T20:47:57Z (GMT). No. of bitstreams: 3 82339.pdf.jpg: 9919 bytes, checksum: 3b6ea77556e57a481dfe578c253dc397 (MD5) 82339.pdf.txt: 271978 bytes, checksum: 30d1b7614545b7576d645b8d658edc63 (MD5) 82339.pdf: 1268046 bytes, checksum: ff1627f95c9dffebb490a8ba67a3a127 (MD5) Previous issue date: 2007-07-17T00:00:00Z / Application of statistical and financial techniques in decision-making models for marketing investments is an area of study with considerable potential that, as yet, is largely unexplored. The Customer Equity model and Customer Lifetime Value Analysis are gaining recognition in the literature in this area, with discussions among academics and practitioners regarding how to project the Net Present Value of future cash flow generated by a client during the lifetime of his commercial relationship with a firm. Despite the recent appearance of several articles in the academic literature describing customer equity calculations, few suggest statistical techniques or estimators for the parameters that could be used by a firm for its own projections. The model used as a reference in this study proposes an original combination involving survival analysis techniques and hierarchical linear models. In this thesis, we will demonstrate how hierarchical linear models can be used as an important tool to understand, explain and predict the gross margin generated by a client. Use of this technique in business administration is a recent development and it has not yet been applied to the calculation of customer lifetime value. This technique, in addition to other advantages, takes into consideration both the individual characteristics of the client and the trend of the margin he generates over time. Survival analysis has been used to predict the probability that a client will maintain a commercial relationship with the firm. In order to make a further contribution in this area, in this study we develop an application based on Cox’s model (1972), using a methodology that also predicts client behavior on the basis of his individual characteristics. As an illustration, the model will be applied in one of the five largest credit card issuers in Brazil. We note that the same model could be applied in industries with similar characteristics, such as telecommunications, internet service providers, banks and finance companies. Given the exploratory nature of this study, its conclusions are limited to the analysis of this sample, however they provide a starting point for further research. / Identifica-se que a aplicação de técnicas estatísticas e financeiras nos modelos para a tomada de decisão dos investimentos de marketing se apresenta muito abaixo de seu potencial. O modelo do Valor do Cliente e o cálculo do Valor Vitalício do Cliente vêm ganhando destaque como referência bibliográfica no tema, provocando discussão nos meios acadêmicos e empresariais em torno de como projetar o fluxo de caixa futuro descontado, gerado por um cliente durante o tempo que manterá relacionamento comercial com a empresa. Apesar de na literatura acadêmica existirem diversos artigos descrevendo o cálculo do Valor do Cliente, poucos sugerem técnicas estatísticas e estimadores que poderiam ser úteis para este fim. O modelo de cálculo usado como referência neste estudo propõe uma combinação original envolvendo as técnicas de análise de sobrevivência com modelos lineares hierárquicos. Nesta tese será demonstrado como os Modelos Lineares Hierárquicos podem ser utilizados como uma importante ferramenta para entender, explicar e prever a margem de contribuição gerada por um cliente. Essa técnica recentemente passou a ser utilizada como ferramenta nas questões relacionadas à Administração de Empresas e ainda não foi aplicada no cálculo do Valor Vitalício do Cliente. Entre outras vantagens, a técnica permite levar em consideração, no cálculo, tanto as características individuais de cada cliente, quanto à tendência da margem gerada por ele ao longo do tempo. A Análise de Sobrevivência foi utilizada para modelar a probabilidade de um cliente manter o relacionamento comercial com a Administradora. Na tentativa de contribuir para o tema, este estudo desenvolveu uma aplicação a partir da modelagem desenvolvida por Cox (1972). Essa metodologia também permite estimar o comportamento do cliente levando em conta suas características individuais. Como ilustração, o modelo será aplicado em uma das cinco principais Administradoras de Cartões de Crédito do Brasil. Vale observar que o mesmo modelo poderia ser aplicado em outras indústrias com características semelhantes, como telefonia, provedores de internet, bancos e financeiras. Dada a natureza exploratória do estudo, suas conclusões se restringem à análise da amostra; entretanto, elas podem se constituir em um ponto de partida para outras pesquisas mais aprofundadas.
293

Não-normalidade multivariada e multicolinearidade em análise de trilha na cultura de milho / Non-normality multivariate and multicollinearity in path analysis in corn

Toebe, Marcos 16 February 2012 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The path analysis allows evaluation of the direct and indirect effects of the explicative variables on variable of interest, through the breakdown of the correlation coefficients. In order to make the results obtained through the path analysis reliable, some assumptions must be met. Thus, the objectives of this study were to verify the normality and the multicollinearity interference in the corn path analysis and compare alternative methods for estimating the path coefficients. Data from 44 trials of corn cultivars was used, carried out in the state of Rio Grande do Sul, between the crop years 2002/03 and 2004/05. In each cultivar, of each trial, were measured (number of days until the male flowering, plant height, ear insertion height, relative position of the ear, number of plants, number of ears and prolificacy) and the main variable (grain yield). For each trial, descriptive statistics were calculated and univariate and multivariate normality diagnoses were conducted using the Shapiro-Wilk test and the Shapiro-Wilk multivariate generalized by Royston test, respectively. Thereupon, in the trials data that did not present a normal distribution, a transformation of the data by the Box-Cox family of transformations was carried out. The correlation coefficients between the seven explicative variables (correlation matrix X'X) and the correlation coefficients of each explicative variable with the grain yield (correlation matrix X'Y) were calculated for the original and transformed data. Then, the multicollinearity was diagnosed in the correlation matrix X'X, using four methods: variance inflation factor, tolerance, the condition number and the matrix determinant. Finally, the path analysis was performed, using the normal equations system X X �� = X Y, in three forms: traditional path analysis, path analysis under multicollinearity and traditional path analysis, with elimination of variables. The data transformation, to obtain multivariate normality, contributes to the degree of multicollinearity decrease and in the stabilization of the direct effects in path analysis with high degree of multicollinearity. The high degrees of multicollinearity adverse effects in the estimation of the direct effects in path analysis are larger than the multivariate non-normality. The traditional path analysis, with elimination of variables, is more appropriate than the path analysis under multicollinearity. / A análise de trilha permite avaliar os efeitos diretos e indiretos de variáveis explicativas sobre a variável de interesse, por meio do desdobramento dos coeficientes de correlação. Para que os resultados gerados pela análise de trilha apresentem confiabilidade adequada, alguns pressupostos devem ser atendidos. Assim, os objetivos deste trabalho foram: verificar a interferência da não-normalidade multivariada e da multicolinearidade em análise de trilha na cultura de milho e, comparar métodos alternativos de estimação dos coeficientes de trilha. Foram utilizados dados de 44 ensaios de competição de cultivares de milho, conduzidos no estado do Rio Grande do Sul, entre os anos agrícolas de 2002/03 e 2004/05. Em cada cultivar, de cada ensaio, foram mensuradas sete variáveis explicativas (número de dias até o florescimento masculino, estatura de plantas, altura de inserção da espiga, posição relativa da espiga, número de plantas, número de espigas e prolificidade) e a variável principal (produtividade de grãos). Para cada ensaio, foram calculadas estatísticas descritivas e realizado o diagnóstico de normalidade uni e multivariada, por meio dos testes de Shapiro-Wilk e de Shapiro-Wilk multivariado generalizado por Royston, respectivamente. A seguir, nos dados dos ensaios que não apresentaram distribuição normal, foi realizada a transformação dos dados com a utilização da família de transformações Box-Cox. Para os dados originais e os dados transformados, foram calculados os coeficientes de correlação entre as sete variáveis explicativas (matriz de correlação X X) e os coeficientes de correlação de cada variável explicativa com a produtividade de grãos (matriz de correlação X Y). A seguir, foi realizado o diagnóstico de multicolinearidade na matriz de correlação X X, por meio de quatro métodos: fator de inflação de variância, tolerância, número de condição e determinante da matriz. Por fim, foi realizada a análise de trilha, com a utilização do sistema de equações normais X X �� = X Y, por três formas: análise de trilha tradicional, análise de trilha sob multicolinearidade e análise de trilha tradicional, com eliminação de variáveis. A transformação de dados, a fim de obter a normalidade multivariada, contribui para a redução do grau de multicolinearidade e na estabilização das estimativas dos efeitos diretos em análise de trilha com alto grau de multicolinearidade. Os efeitos adversos do alto grau de multicolinearidade na estimativa dos efeitos diretos de análises de trilha são maiores que a não-normalidade multivariada. A análise de trilha tradicional, com eliminação de variáveis, é mais adequada que a análise de trilha sob multicolinearidade.
294

Uma aproximação do tipo Euler-Maruyama para o processo de Cox-Ingersoll-Ross

Ferreira, Ricardo Felipe 26 February 2015 (has links)
Made available in DSpace on 2016-06-02T20:06:10Z (GMT). No. of bitstreams: 1 6520.pdf: 1838901 bytes, checksum: 35b2a71ea573764ae46492a67c0ef3d6 (MD5) Previous issue date: 2015-02-26 / Universidade Federal de Sao Carlos / In this master's thesis we work with Cox-Ingersoll-Ross (CIR) process. This process was originally proposed by John C. Cox, Jonathan E. Ingersoll Jr. and Stephen A. Ross in 1985. Nowadays, this process is widely used in financial modeling, e.g. as a model for short-time interest rates or as volatility process in the Heston model. The stochastic diferential equation (SDE) which defines this model does not have closed form solution, so we need to approximate the process by some numerical method. In the literature, several numerical approximations has been proposed based in interval discretization. We approximate the CIR process by Euler-Maruyama-type method based in random discretization proposed by Leão e Ohashi (2013) under Feller condition. In this context, we obtain an exponential convergence order for this approximation and we use Monte Carlo techniques to compare the numerical results with theoretical values. / Nesta dissertação de mestrado nós trabalhamos com o processo de Cox-Ingersoll- Ross, que foi originalmente proposto por John C. Cox, Jonathan E. Ingersoll Jr. e Stephen A. Ross em 1985. Este processo é amplamente utilizado em modelagem financeira, por exemplo, para descrever a evolução de taxas de juros ou como o processo de volatilidade no modelo de Heston. A equação diferencial estocástica que define este processo não possui solução fechada, logo faz-se necessária a aproximação do processo via algum método numérico. Na literatura diversos trabalhos propõem aproximações baseadas em esquemas de discretização intervalar. Nós aproximamos o processo de Cox-Ingersoll-Ross através de um método numérico do tipo Euler- Maruyama baseado na discretização aleatória proposta por Leão e Ohashi (2013) sob a condição de Feller. Neste contexto, mostramos que esta aproximação possui uma ordem de convergência exponencial e utilizamos técnicas de simulação Monte Carlo para comparar resultados numéricos com valores teóricos.
295

AvaliaÃÃo clÃnica da corticoterapia intralesional em lesÃo cen-tral de cÃlulas gigantes dos maxilares : relevÃncia da expressÃo dos receptores de corticÃide e calcitonina, Cox-2, p16 e amplificaÃÃo da ciclina D1 / Clinical Assessment of Intralesional Corticotherapy for Central Giant Cells Lesion Of The Jaws â The Relevance Of Steroid Receptor Expression And Calcitonin, Cox-2, P16 and Amplification of Cyclin D1. Author: Ranato Luiz Maia Nogueira. Leader: Prof. Dr. Ronaldo Albuquerque Ribeiro.

Renato Luiz Maia Nogueira 30 July 2010 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A LesÃo Central de CÃlulas Gigantes dos maxilares (LCCG) à intra-Ãssea, nÃo tem predileÃÃo por sexo, classifica-se em agressivas e nÃo-agressivas, histologicamente consistem tecido fi-broso e celularizado fusiforme associado a cÃlulas gigantes multinucleadas (CGM), focos de hemorragia e neovascularizaÃÃo, tendo na cirurgia seu habitual tratamento. Novas abordagens terapÃuticas foram propostas, sendo a principal delas o uso de corticÃides intralesionais. Este trabalho analisa retrospectivamente 21 pacientes portadores de LCCG que foram tratados por hexacetonido de triancinolona intralesional, atravÃs do seguinte protocolo: injeÃÃo de hexace-tonido de triancinolona 20mg/ml diluÃdo na soluÃÃo anestÃsica de lidocaÃna 2%/epinefrina 1:200.000 numa proporÃÃo de 1:1; infiltrando 1ml de soluÃÃo para cada 1cm3 de lesÃo, totali-zando 06 aplicaÃÃes em intervalos quinzenais. Estabeleceu-se 04 critÃrios clÃnicos para classi-ficar a resposta ao tratamento: 1- estabilizaÃÃo ou regressÃo clÃnica da lesÃo 2- ausÃncia de sintomas 3- aumento da densidade nos controles radiogrÃficos 4- aumento da resistÃncia a infiltraÃÃo intralesional da droga, bem como, fez-se uma anÃlise imunohistoquÃmica quanto à expressÃo dos Receptores de corticÃides (GCR) e Calcitonina (CTR), Cox-2, proteÃna p16 e amplificaÃÃo gÃnica da Ciclina D1 por CISH, comparando quanto a agressividade e a resposta terapÃutica a corticoterapia intralesional. Dos 21 pacientes incluÃdos neste estudo, 11 eram homens e 10 mulheres, 09 tinham lesÃo em maxila, 12 em mandÃbula. Dez eram lesÃes agres-sivas e 11 nÃo-agressivas, 15 (71,4%) apresentaram uma boa resposta ao tratamento, 04(19%) moderada e 02(9,1%) negativa. Das 11 nÃo agressivas, 10(90,9%) apresentaram boa resposta e 01 (9,1%) resposta moderada, das 10 agressivas 05(50%), 03(30%) e 02(20%) apresentaram boa, moderada e negativa resposta respectivamente, nenhuma apresentou recidiva apÃs o tra-tamento, com preservaÃÃo que variou entre 04 a 08 anos. Os achados histopatolÃgicos mos-traram uma reduÃÃo da densidade e do tamanho das CG, e um estroma fibro-colagenoso das lesÃes. Dentre os marcadores pesquisados, apenas GCR em CG antes do tratamento mostrou significÃncia estatÃstica (p<0,004) com relaÃÃo a uma boa resposta terapÃutica. O CTR ex-pressou-se em cÃlulas gigantes e mononucleares de forma variada. A p16 apresentou-se ex-pressa em 30% da amostra, COX2 nÃo apresentou expressÃo na lesÃo e 33% da amostra apre-sentou amplificaÃÃo gÃnica da ciclina D1. NÃo mostraram significÃncia estatÃstica nem quanto à agressividade, nem quanto resposta ao tratamento, nenhum dos marcadores, exceto o GCR. O estudo mostrou que a corticoterapia intralesional à efetiva e segura para o tratamento das LCCG, com tendÃncia a melhor resposta nas lesÃes nÃo-agressivas do que nas agressivas. Mostrou ainda que a marcaÃÃo para GCR em CG demonstrou ser um parÃmetro confiÃvel para prever a resposta à terapÃutica com a corticoterapia intralesional e que 33% das LCCG tÃm comportamento neoplÃsico pela amplificaÃÃo gÃnica da ciclina D1. / Central Giant Cells Lesion (CGCL) of the jaws is an intra-bone lesion with no predilection for sex and clinically divided into aggressive and non-aggressive subtypes. Histological, it shows as fibrous tissue with fusiform cells, as well as multinucleated giant cells (GC) clusters, he-morrhagic foci and neovascularization. Surgery is the regular treatment option. As new the-rapeutic approaches have been proposed, intralesional glucocorticoid injection is the main option. This paper assesses retrospectively 21 patients presenting CGCL, treated with intrale-sional triamcinolone hexacetonide by using the following protocol: intralesional injection of triamcinolone hexacetonide 20mg/mL, diluted in a solution of lidocain 2% plus epinephrine 1:200000, at a 1:1 proportion; 1mL of this final solution for each 1cm3 of lesion volume was the injected, with a total of 06 injections, one in every 15 days. Four clinical criteria were sta-bilished to evaluate treatment outcome: 1- Clinical regression or stabilization of the lesion; 2- Absence of symptoms; 3- Raising in density on radiographic controls; 4-Increased resistence when injecting the drug intralesionally. It was also performed immunohistochemical assess-ment for glucocorticoid receptor (GCR) expression, calcitonin receptor (CTR) expression, COX-2 expression, p16 expression and Ciclin D1 gene amplification by CISH, making com-parisons related to aggressivity and to therapeutic outcome. Eleven out of 21 patients of this study were women, and 10 were men. Nine of the patients had lesion located in the maxilla, 12 in the mandible. Ten patients showed aggressive lesions and 11 non-aggressive lesions. Fifteen patients showed good treatment outcome, four patients showed moderate outcome, and two patients showed negative answer to the treatment. Among the 11 patients with non-aggressive lesions, ten showed good outcome and the other, moderate outcome. Among the ten aggressive lesions, five patients showed good outcome, three patients showed moderate outcome and the remaining two patients showed negative answer to the treatment. None of them showed reicidive in a four to eight years follow-up period. Morphologic analysis found positive correlation between volume density of GC/mm2 and lesion aggressiveness, as well as significant reduction in number of GC/mm2 after treatment. Among the markers, only GCR in GC showed statistical relevance associated to the treatment. CTR was espresse in GC and in mononuclear cells in a varying way; p16 was expressed in 30% of the sample; COX-2 was not expressed at all in lesion samples and 33% of the sample showed gene amplification in Ciclin D1. None of the markers showed any statistical significant difference related to aggres-siveness nor to treatment outcome, except for GCR. The study showed the feasibility of the adopted treatment, with tendency to better outcomes in non-aggressive lesion, if compared to the aggressive ones. It also showed evidence pointing to GCR expression in GC as a reliable parameter to predict therapeutic responsiveness to glucocorticoids; and it showed that 33% of CGCL have neoplastic behaviour by Ciclin D1 gene amplification.
296

Modélisation et simulation à l' échelle du pore de la récupération assistée des hydrocarbures par injection de polyméres / Pore-scale numerical simulation of Oil Recovery by polymer injection

Pinilla Velandia, Johana Lizeth 13 December 2012 (has links)
Ce travail est motivé par la nécessité de mieux comprendre la technique de récupération du pétrole par injection de polymères à l'échelle du pore. On considère deux fluides immiscibles dans un réseau de microcanaux. A cette échelle, le diamètre des canaux est de l'ordre de quelques dizaines de micromètres tandis que la vitesse est de l'ordre du centimètre par seconde. Cela nous permet d'utiliser les équations de Stokes incompressible pour décrire l'écoulement des fluides. Le modèle Olroyd-B est utilisé pour décrire l'écoulement du fluide viscoélastique. Afin d'effectuer des simulations numériques dans une géométrie complexe comme un réseau de microcanaux, une méthode de pénalisation est utilisée. Pour suivre l'interface entre les deux fluides, la méthode Level-Set est employée. Le modèle pour la dynamique de la ligne triple est basé sur les la loi de Cox. Enfin, on présente des résultats de simulations numériques avec des paramètres physiques réalistes. / This work is motivated by the need for better understanding the polymer Enhanced Oil Recovery (EOR) technique at the pore-scale. We consider two phase immiscible fluids in a microchannel network. In microfluidics, the diameter of the channels is of the order of a few tens of micrometers and the flow velocity is of the order of one centimeter per second. The incompressible Stokes equations are used to describe the fluid flow. The Oldroyd-B rheological model is used to capture the viscoelastic behavior. In order to perform numerical simulations in a complex geometry like a microchannel network, a penalization method is implemented. To follow the interface between the two fluids, the Level-Set method is employed. The dynamic contact line model used in this work is based on the Cox law. Finally, we perform simulations with realistic parameters.
297

Novel prognostic biomarkers for renal cell carcinoma

Ronkainen, H.-L. (Hanna-Leena) 13 March 2012 (has links)
Abstract Background and aims: Stage and grade are the most widely used prognostic parameters for renal cell carcinoma (RCC). The clinical course of this disease is not, however, always predictable by traditional prognostic factors. In the era of new molecular targeted therapies a more accurate prognostication of RCC patient survival is important for the individualization of treatment and follow-up of patients. Despite exhaustive research there are still no prognostic biomarkers for RCC in clinical practice. In order to find novel prognostic tissue markers for RCC, we examined the expression of 14 biomarkers involved in carcinogenesis and clarified their prognostic significance in RCC. Material and methods: Out of 189 consecutive patients who underwent surgery for kidney cancer at Oulu University Hospital in the 1990s, 152 patients with histologically verified RCC were included in this study. The stage distribution was 70 (46%), 12 (8%), 51 (34%) and 19 (12%) patients with stages I-IV, respectively. The majority of the tumours (83 tumours, 55%) were nuclear grade II and 5 (3%), 40 (27%) and 22 (15%) of the tumours were grades I, III and IV, respectively. Clinical and follow-up data were obtained from patient records, the Finnish Cancer Registry and on demand from the Population Register Centre of Finland. The biomarkers studied included markers of the oxidative and neuroendocrine systems as well as proteins related to cell adhesion and migration, invasion, metastasis, inflammation and immune responses. The expression of various biomarkers was characterized via immunohistochemical tests of archival tumour material. The staining intensity was compared to clinicopathological parameters and patient RCC-specific survival. Results: The 5-year RCC-specific survival was 77%. The expression of Toll-like receptor 9 (TLR9) was an independent marker of favourable RCC-specific survival whereas cytoplasmic myosin VI expression was found to be an independent prognostic factor of poor RCC-specific survival. Cell culture experiments showed how cyclooxygenase-2 (COX-2) expression is regulated by HuR in RCC. HuR and COX-2 immunoexpression were also related to decreased RCC-specific survival. Immunostaining of Keap1 was associated with advanced RCC and a marker of a poorer RCC-specific prognosis. The expression of different neuroendocrine markers was evaluated but we could not establish any prognostic value for them. Conclusions: In particular, TLR9, HuR and myosin VI can be regarded as promising novel prognostic biomarkers in RCC. Stage, however, is the most important single prognostic factor for RCC. / Tiivistelmä Munuaissyöpä on vuosikymmenten ajan jatkuvasti yleistynyt. Vaikka se diagnosoidaan nykyisin useimmiten sattumalöydöksenä vatsan alueen kuvantamistutkimuksissa ja hoitomenetelmät ovat viime vuosikymmenten aikana kehittyneet, munuaissyöpäkuolleisuus ei ole laskenut. Munuaissyövän ennusteen määrittäminen voi olla haasteellista. Perinteiset ennustetekijät, levinneisyys ja erilaistumisaste, eivät riitä selittämään kaikkien potilaiden taudinkulkua, eikä munuaissyövälle vielä ole kliinisessä käytössä ennusteellista merkkiainetta. Munuaissyöpähoitojen kehittyessä taudinkulun ennustaminen on yhä tärkeämpää, jotta potilaiden hoito ja seuranta voidaan yksilöidä. Tämän väitöskirjatyön tarkoituksena oli etsiä uusia ennusteellisia kudosmerkkiaineita munuaissyöpäkasvaimille. Väitöskirjatutkimus perustuu 1990-luvulla Oulun yliopistollisessa sairaalassa leikatun 152 munuaissyöpäpotilaan aineistoon. Lähes puolet aineiston kasvaimista edusti levinneisyysluokkaa I, ja yli puolet munuaissyöpäkasvaimista oli hyvin erilaistuneita (tumagradus I ja II). Tutkimuspotilaista kerättiin kattavat seurantatiedot. Leikkauksessa poistettujen munuaissyöpäkasvainten arkistomateriaalista tutkittiin eri merkkiaineiden ilmenemistä. Tutkitut merkkiaineet käsittivät oksidatiivisen ja neuroendokriinisen järjestelmän merkkiaineita sekä valkuaisaineita, jotka liittyvät keskeisiin syövän ominaisuuksiin, kuten solujen välisiin liitoksiin ja solujen liikkumiseen sekä etäpesäkkeiden syntymiseen. Lisäksi tutkittiin merkkiaineita, jotka liittyvät tulehdusreaktioihin ja immuunipuolustukseen. Väitöskirjatutkimus paljasti useita uusia kudosmerkkiaineita, joiden ilmeneminen munuaissyöpäkasvaimessa on yhteydessä potilaan ennusteeseen. Näistä merkittävimpiä ovat myosiini VI, joka liittyy syöpäkasvainten metastasointiin, sekä immuunipuolustuksessa vaikuttava Tollin kaltainen reseptori 9 (Toll-like receptor 9, TLR9). Molemmat merkkiaineet osoittautuivat itsenäisiksi ennustetekijöiksi munuaissyövässä. Muita ennusteeseen vaikuttavia merkkiaineita ovat tutkimuksen mukaan oksidatiivista stressiä aistiva Keap1 sekä immunologisiin reaktioihin liittyvä syklo-oksigenaasi 2 (COX-2) ja sen ilmenemistä säätelevä HuR.
298

Bostad till salu : En analys av tid-till-försäljning på Uppsalas bostadsmarknad

Eriksson, Fabian, Ajdert, Alexander January 2022 (has links)
Denna uppsats har undersökt tid-till-försäljning på Uppsala kommuns bostadsmarknad för lägenheter under året 2021. För att analysera tid-till-försäljning har metoder från överlevnadsanalys använts. Överlevnadsfunktionen och den kumulativa hasardfunktionen har skattats med Kaplan-Meier-skattningen och Nelson-Aalen-skattningen. Därutöver har tre modeller skattats; en Cox proportionell hasardmodell och två 'Accelerated Failure Time'-modeller varav en var en Weibullmodell och en var en Loglogistiskmodell. Resultaten indikerar att tid-till-försäljning har en hög hasard efter två veckor på marknaden varefter en avtagande hasard. Resultaten indikerar att kovariat har en statistisk signifikant effekt på tid-till-försäljning. Grafiska tester indikerar att antagandet om proportionalitet för Cox proportionella hasardmodell och antagandet om den underliggande hasardfunktionen för Weibullmodellen är orimliga. Antagandet om den underliggande hasardfunktionen för loglogistiskamodellen verkar rimlig. Goodness-of-fit indikerar att Weibullmodellen och loglogistiskamodellen var mer välanpassade till datamaterialet än Cox proportionella hasardmodell. / This bachelor's thesis has investigated time-to-sale on the Uppsala municipality property market for apartments during 2021. Analysis has been performed utilising methods from survival analysis. Both the survival function and cumulative hazard function were estimated using the Kaplan-Meier estimate and the Nelson-Aalen estimate respectively. Furthermore, three models were estimated; a Cox Proportional Hazards model as well as two Accelerated Failure Time models of which one was a Weibullmodell and the other was a loglogistic model. The results indicate that time-to-sale has a high hazard after two weeks on the market followed by a decreasing hazard. The results also indicate that covariates have a statistically significant effect on time-to-sale. Graphical tests indicate that the assumption of proportionality for the Cox Proportional Hazards model and the assumption of the underlying hazard function for the Weibullmodell are unreasonable. The assumed hazardfunction of the loglogistic model was found to be reasonable. Goodness of fit indicates that the Weibull model and loglogistic model were a better fit to the data than the Cox proportional Hazardsmodel.
299

Immunhistochemische Untersuchungen zur Expression von Tumormarkern und Wachstumsfaktorrezeptoren bei Hunden mit malignen Nasentumoren

Pauly, Ljuba Anna Maria 24 March 2022 (has links)
Einleitung: Nasenhöhlentumoren stellen mit bis zu 47 % die Hauptursache für Nasenausfluss beim Hund dar. Sie sind überwiegend maligne, zu 60 % Karzinome und zu 34 % Sarkome. Die mediane Überlebenszeit (MÜZ) liegt ohne Therapie bei etwa drei Monaten. Nach einer Bestrahlungstherapie beträgt sie etwa 8-20 Monate. Eine Therapie mit klassischen Chemotherapeutika oder eine Tumorablation über eine offen-chirurgische Rhinotomie führen nicht zu einer Verlängerung der Überlebenszeit. Durch ein neues Therapieverfahren, die endoskopisch interventionelle Zytoreduktion (EIZ), werden bei deutlich weniger Nebenwirkungen und Sitzungen in Allgemeinanästhesie ähnliche Überlebenszeiten erreicht wie durch eine Radiotherapie. Da es sich bei der EIZ um eine Zytoreduktion handelt, bei der die Nasenhöhlentumoren nicht mit Sicherheitsabstand im gesunden Gewebe entfernt werden können, stellt sich die Frage, ob die Überlebenszeit zusätzlich durch adjuvante Therapeutika verlängert werden kann. Als solche kommen beispielsweise Tyrosinkinase-Inhibitoren (TKI) und Cyclooxygenase-2 (COX-2)-Inhibitoren infrage, deren Zielstruktur-Expression besonders in kaninen nasalen Sarkomen noch unbekannt ist. Ziele der Untersuchungen: Ziel dieser Arbeit ist, anhand von Bioptaten von kaninen nasalen Karzinomen und Sarkomen eine immunhistochemische Charakterisierung durchzuführen. Hierzu wurden 10 Marker ausgewählt. Besonders im Fokus standen die Wachstumsfaktorrezeptoren vascular endothelial growth factor receptor-2 (VEGFR-2) und epidermal growth factor receptor (EGFR) sowie COX-2, die ersten beiden als Zielstrukturen von TKI und der letztere als Zielstruktur von COX-2-Inhibitoren. So soll eine Wirksamkeit dieser Medikamente bei kaninen nasalen Karzinomen und Sarkomen evaluiert werden. Weiterhin soll eine Korrelation zwischen der Expression von bestimmten Markern (p53, Ki-67, aktivierte Caspase-3, Survivin, E-Cadherin) mit den klinischen Daten zur Tumorkategorie und Überlebenszeit der Patienten untersucht werden. Außerdem soll als Grundlage für den Einsatz neuartiger Medikamente analysiert werden, ob EGFR, VEGFR-2 oder COX-2 in Karzinomen und Sarkomen unterschiedlich stark exprimiert werden. Tiere, Material und Methoden: Es wurden 19 Karzinome, sieben Sarkome und drei andere Tumorarten (ein malignes Melanom, zwei undifferenzierte maligne Tumoren unklarer Histogenese) retrospektiv immunhistochemisch auf die Expression von EGFR, VEGFR-2, COX-2, p53, Ki-67, aktivierter Caspase-3, Survivin, E-Cadherin, Zytokeratinen und Vimentin untersucht. Von drei Patienten wurden insgesamt vier Rezidivbioptate entnommen und ebenfalls immunhistochemisch untersucht. Beidseitige Nasenschleim-hautbioptate von neun gesunden Beagles dienten als Kontrollgruppe (genehmigungspflichtiger Tierversuch: TVV 02/18, Landesdirektion Sachsen). Alle Bioptate wurden während einer standardisierten Diagnostik mit computer-/ magnetresonanztomographischer Untersuchung - bei der auch ein Staging in vier Tumor-Kategorien (T1-T4) durchgeführt wurde - und Rhinoskopie zwischen Jan. 2015 und Dez. 2018 entnommen. Die immunhistochemische Untersuchung der in Formalin fixierten und in Paraffin eingebetteten Gewebeschnitte wurde mit der Avidin-Biotin-Komplex-Methode durchgeführt, nachdem die histopathologischen Diagnosen an Hämatoxylin-Eosin-gefärbten Schnitten gestellt wurden. Die immun-histochemischen Färbungen wurden entweder quantitativ oder semiquantitativ ausgewertet. Die Ergebnisse wurden auf Normalverteilung getestet und u.a. mit One-way Anova oder Kruskal-Wallis Test analysiert. Die MÜZ wurde mit der Kaplan Meier Methode berechnet und mit Log-Rank Test und Gehan-Breslow-Wilcoxon Test verglichen (Signifikanzniveau alpha = 5 %). Ergebnisse: 29 Hunde haben die Einschlusskriterien erfüllt. 14 Hunde wurden unmittelbar nach der Diagnostik euthanasiert; 15 Hunde wurden mit einer EIZ behandelt. Die MÜZ der Patienten in T1 (n = 3) nach EIZ betrug 1362 Tage und war signifikant länger als die MÜZ der Patienten in T2 (n = 1) mit 379 Tagen, in T3 (n = 8) mit 250 Tagen und in T4 (n = 1) mit 75 Tagen (p = 0,0062). Von den nasalen Karzinomen zeigten 68 % für EGFR, 100 % für VEGFR-2, 63 % für COX-2, 100 % für Survivin und 100 % für E-Cadherin eine immunhistochemisch positive Reaktion. Von den nasalen Sarkomen reagierten 100 % für VEGFR-2, 57 % für COX-2 und 86 % für Survivin positiv. Die Proteine EGFR und E-Cadherin werden ausschließlich von epithelialen Zellen exprimiert. Die Expression lag somit bei den vorliegenden Sarkomen bei 0 %. Unter den anderen Tumoren waren 33 % für EGFR, 100 % für VEGFR-2, 67 % für COX-2, 67 % für Survivin und 67 % für E-Cadherin positiv. Die mediane Expression von p53 lag bei 0,9 %, von Ki-67 bei 25 % und von aktivierter Caspase-3 bei 0,7 %. Die Unterschiede in der Expression von EGFR, VEGFR-2, COX-2, p53, Ki-67, aktivierter Caspase-3, Survivin und E-Cadherin zwischen den einzelnen histogenetischen Gruppen sowie zwischen den vier Tumor-Kategorien und in der MÜZ waren nicht signifikant. Eine Korrelation der VEGFR-2-Expression mit der MÜZ oder den T-Kategorien konnte nicht untersucht werden, da alle Tumoren der drei histogenetischen Gruppen VEGFR-2-positiv waren. 100 % der Karzinome zeigten eine Zytokeratin-Expression, 0 % eine Vimentin-Expression. Sarkome verhielten sich dazu konträr. In den anderen Tumoren konnten weder Zytokeratine noch Vimentin immunhistochemisch nachgewiesen werden. In den Rezidivbioptaten war ein Anstieg der COX-2 und aktivierte-Caspase-3-Expression zu beobachten, der aufgrund der geringen Fallzahl nicht statistisch untersucht werden konnte. Schlussfolgerungen: In der vorliegenden Studie wurden erstmalig kanine nasale Karzinome und Sarkome vergleichend immunhistochemisch untersucht. Weiterhin konnte erstmalig gezeigt werden, dass auch mesenchymale und andere Tumoren in vergleichbarer Häufigkeit wie Karzinome der Nase COX-2 exprimieren, wodurch ein Einsatz von COX-2-Inhibitoren nach einer Zytoreduktion bei Nasenhöhlentumoren allgemein von Nutzen sein könnte. Da alle Tumoren VEGFR-2 und die Mehrzahl der Karzinome (68 %) EGFR exprimierten, könnte eine adjuvante Therapie nach EIZ durch einen TKI mit VEGFR-2 oder EGFR als Zielstruktur einen positiven Einfluss auf die Überlebenszeit der erkrankten Hunde haben. Durch die Expression von E-Cadherin und Zytokeratinen in 100 % der Karzinome und 0 % der Sarkome sowie der Expression von Vimentin in 0 % der Karzinome und 100 % der Sarkome konnte die histopathologische Diagnose im Hinblick auf die Histogenese der Tumoren bestätigt werden. Auf der Grundlage der Ergebnisse der vorliegenden Studie sollte eine klinische Studie zur Anwendung von TKI und COX-2-Inhibitoren zur Untersuchung der klinischen Wirksamkeit und Sicherheit bei nasalen Tumoren von Hunden durchgeführt werden.:1 EINLEITUNG 1 2 LITERATURÜBERSICHT 2 2.1 Physiologie der Nasenhöhle 2 2.1.1 Anatomischer und histologischer Aufbau 2 2.1.2 Funktionen der Nasenhöhle und Nasenschleimhaut 3 2.2 Tumoren der Nase und der Nasennebenhöhlen 3 2.2.1 Prävalenz und Signalement von Hunden mit Nasentumoren 3 2.2.2 Biologisches Verhalten der Tumoren 3 2.3 Klinische Symptome 4 2.4 Diagnostik 5 2.4.1 Laboruntersuchungen 5 2.4.2 Bildgebende Verfahren 6 2.4.3 Rhinoskopie 9 2.4.4 Histopathologische Untersuchung 10 2.5 Therapieoptionen 10 2.5.1 Radiotherapie 10 2.5.2 Rhinotomie 11 2.5.3 Chemotherapie 11 2.5.4 Endoskopisch interventionelle Zytoreduktion (EIZ) 12 2.5.5 Tyrosinkinase-Inhibitoren 13 2.5.6 Antikörper gegen Rezeptortyrosinkinasen 15 2.5.7 Cyclooxigenase-Inhibitoren 16 2.6 Prognose 16 2.7 Zielantigene für die Immunhistochemie 17 2.7.1 Epidermal growth factor receptor (EGFR) 17 2.7.2 Vascular endothelial growth factor receptor-2 (VEGFR-2) 18 2.7.3 Cyclooxygenase-2 (COX-2) 18 2.7.4 p53 19 2.7.5 Ki-67 19 2.7.6 Aktivierte Caspase-3 20 2.7.7 Survivin 20 2.7.8 E-Cadherin 21 2.7.9 Zytokeratine 21 2.7.10 Vimentin 21 3 HUNDE, MATERIAL UND METHODEN 22 3.1 Patienten 22 3.2 Bioptate und Einschlusskriterien 23 3.3 Kontrolltiere 24 3.4 Immunhistochemische Untersuchungen 25 3.5 Auswertung der immunhistochemischen Reaktionen 28 3.6 Statistische Auswertung 29 4 ERGEBNISSE 31 4.1 Patienten 31 4.1.1 Signalement und Anamnese 31 4.1.2 Einteilung der Patienten in T-Kategorien 33 4.1.3 Histopathologische Befunde 34 4.1.4 Mediane Überlebenszeit nach endoskopisch interventioneller Zytoreduktion 34 4.1.5 Gesunde Kontrollgruppe 35 4.2 Ergebnisse der immunhistochemischen Untersuchungen 37 4.2.1 Kontrollen und Absorptionsreaktionen 37 4.2.2 Epidermal growth factor receptor (EGFR) 37 4.2.3 Vascular endothelial growth factor receptor-2 (VEGFR-2) 40 4.2.4 Cyclooxygenase-2 (COX-2) 42 4.2.5 p53 46 4.2.6 Ki-67 48 4.2.7 Aktivierte Caspase-3 50 4.2.8 Survivin 52 4.2.9 E-Cadherin 55 4.2.10 Zytokeratine 58 4.2.11 Vimentin 58 4.2.12 Bioptate von Tumorrezidiven 60 5 DISKUSSION 62 6 ZUSAMMENFASSUNG 84 7 SUMMARY 86 8 LITERATURVERZEICHNIS 88 9 ANHANG 105 9.1 Übersicht über die Hunde und Bioptate 105 9.2 Ergebnistabellen 107 9.3 Immunhistochemisches Reaktionsprotokoll 120 9.4 Ansatz der Lösungen und Puffer für die Immunhistochemie 122 9.5 Bezugsquellen für Geräte, Einmalartikel, Reagenzien und Chemikalien 123 9.6 Abbildungs- und Tabellenverzeichnis 125 / Introduction: Tumours of the nasal cavity are the main cause of nasal discharge in dogs (up to 47 %). They are almost always malignant, 60 % are carcinomas and 34 % are sarcomas. Without performing any treatment, the median survival time (MST) is about three months. After radiation therapy, the MST is about 8-20 months. A therapy with conventional chemotherapeutics or tumour ablation via open surgical rhinotomy does not prolong the survival time. A new treatment method, the endoscopic interventional cytoreduction (EIC), achieves survival times similar to radiotherapy with considerably fewer sessions under general anaesthesia and fewer potential adverse events. As EIC is a cytoreduction procedure in which the intranasal tumours cannot be removed with safety margins in surrounding healthy tissue, the question arises whether survival could be prolonged by an additional application of adjuvant therapeutics. As such, for example, tyrosine kinase inhibitors (TKIs) and cyclooxygenase-2 (COX-2) inhibitors may be considered, whose target expression is still unknown, especially in canine nasal sarcomas. Aims of the study: One aim of this study is to perform an immunohistochemical characterisation on the basis of biopsy specimens from canine nasal carcinomas and sarcomas. For this purpose, 10 markers were selected. We particularly focused on the growth factor receptors vascular endothelial growth factor receptor-2 (VEGFR-2) and epidermal growth factor receptor (EGFR) as well as COX-2, the first two being targets of TKIs and the latter one being the target of COX-2-inhibitors. Thus, a possible efficacy of these drugs in canine nasal carcinomas and sarcomas should be evaluated. Furthermore, a correlation between the expression of specific markers (p53, Ki-67, cleaved caspase-3, survivin, E-cadherin) with clinical data of the tumour stage and patient survival time should be investigated. Moreover, it will be analysed as a basis for the use of novel drugs whether EGFR, VEGFR-2 or COX-2 are differentially expressed in carcinomas and sarcomas. Animals, Material and Methods: A total of 19 carcinomas, seven sarcomas and three other tumour types (one malignant melanoma, two undifferentiated malignant tumorus of unclear histogenesis) were retrospectively examined by immunohistochemistry for the expression of EGFR, VEGFR-2, COX-2, p53, Ki-67, cleaved caspase-3, survivin, E-cadherin, cytokeratins and vimentin. A total of four biopsies from recurrent tumours were obtained from three patients and also examined by immunohistochemistry. Bilateral nasal mucosal samples from nine healthy beagles served as a control group (animal experiment requiring approval: TVV 02/18, Directorate of the Federal State of Saxony, Germany). All biopsy specimens were collected during a standardised diagnostic procedure with computer /magnetic resonance tomography, which also included a staging into four tumour stages (T1-T4) and rhinoscopy between Jan 2015 and Dec 2018. The immunohistochemical examination of tissue sections fixed in formalin and embedded in paraffin was performed using the avidin-biotin complex method after histopathological diagnoses had been made on haematoxylin-eosin stained sections. The immunohistochemically stained sections were evaluated either quantitatively or semiquantitatively. Results were tested for normal distribution and analysed by the one-way anova or Kruskal-Wallis test, among others. MST was calculated using the Kaplan Meier method and compared with the log-rank test and Gehan-Breslow-Wilcoxon test (significance level alpha = 5 %). Results: A total of 29 dogs met the inclusion criteria. A total of 14 dogs were euthanised immediately after diagnosis; 15 dogs were treated with an EIC. The MST of patients in T1 (n = 3) after EIC was 1362 days and was significantly longer than the MST of those patients in T2 (n = 1) at 379 days, T3 (n = 8) at 250 days and T4 (n = 1) at 75 days (p = 0.0062). Of the nasal carcinomas, 68 % were immunohistochemically positive for EGFR, 100 % for VEGFR-2, 63 % for COX-2, 100 % for survivin and 100 % for E-cadherin. Of the nasal sarcomas, 100 % reacted positively for VEGFR-2, 57 % for COX-2 and 86 % for survivin. The proteins EGFR and E-cadherin were expressed exclusively by epithelial cells and, therefore, the expression was 0 % in the present sarcomas. Amongst the other tumours, 33 % were positive for EGFR, 100 % for VEGFR-2, 67 % for COX-2, 67 % for survivin and 67 % for E-cadherin. The median expression of p53 was 0.9 %, that of Ki-67 25 % and that of cleaved caspase-3 0.7 %. Differences in expression of EGFR, VEGFR-2, COX-2, p53, Ki-67, cleaved caspase-3, survivin and E-cadherin among the histogenetic groups, the four tumour stages and in MST were not significant. However, a correlation of VEGFR-2 expression with MST or the tumour stages could not be investigated because all tumours in the three histogenetic groups were VEGFR-2 positive. A total of 100 % of carcinomas showed cytokeratin expression, and 0 % showed vimentin expression. Sarcomas behaved in a contrary manner. In the other tumours, neither cytokeratins nor vimentin could be detected by immunohistochemistry. An increase in COX-2 and cleaved caspase-3 expression was observed in the recurrent tumour biopsies, which could not be statistically investigated due to the small number of cases. Conclusions: In the present study, canine nasal carcinomas and sarcomas were investigated comparatively by immunohistochemistry for the first time. Again, it was shown for the first time that mesenchymal and other tumours also express COX-2 at comparable frequencies to carcinomas of the nose, suggesting that the use of COX-2 inhibitors after cytoreduction may be of general benefit in nasal cavity tumours. As all tumours expressed VEGFR-2 and the majority of carcinomas (68 %) expressed EGFR, the adjuvant therapy after EIC by a TKI targeting VEGFR-2 or EGFR could have a beneficial effect on the survival of diseased dogs. The expression of E-cadherin and cytokeratins in 100 % of the carcinomas and 0 % of the sarcomas as well as the expression of vimentin in 0 % of the carcinomas and 100 % of the sarcomas confirmed the histopathological diagnosis with regard to the histogenesis of the tumours. Based on these results of the present study, a clinical trial should be performed on the use of TKIs and COX-2 inhibitors to investigate the clinical efficacy and safety of canine nasal tumours.:1 EINLEITUNG 1 2 LITERATURÜBERSICHT 2 2.1 Physiologie der Nasenhöhle 2 2.1.1 Anatomischer und histologischer Aufbau 2 2.1.2 Funktionen der Nasenhöhle und Nasenschleimhaut 3 2.2 Tumoren der Nase und der Nasennebenhöhlen 3 2.2.1 Prävalenz und Signalement von Hunden mit Nasentumoren 3 2.2.2 Biologisches Verhalten der Tumoren 3 2.3 Klinische Symptome 4 2.4 Diagnostik 5 2.4.1 Laboruntersuchungen 5 2.4.2 Bildgebende Verfahren 6 2.4.3 Rhinoskopie 9 2.4.4 Histopathologische Untersuchung 10 2.5 Therapieoptionen 10 2.5.1 Radiotherapie 10 2.5.2 Rhinotomie 11 2.5.3 Chemotherapie 11 2.5.4 Endoskopisch interventionelle Zytoreduktion (EIZ) 12 2.5.5 Tyrosinkinase-Inhibitoren 13 2.5.6 Antikörper gegen Rezeptortyrosinkinasen 15 2.5.7 Cyclooxigenase-Inhibitoren 16 2.6 Prognose 16 2.7 Zielantigene für die Immunhistochemie 17 2.7.1 Epidermal growth factor receptor (EGFR) 17 2.7.2 Vascular endothelial growth factor receptor-2 (VEGFR-2) 18 2.7.3 Cyclooxygenase-2 (COX-2) 18 2.7.4 p53 19 2.7.5 Ki-67 19 2.7.6 Aktivierte Caspase-3 20 2.7.7 Survivin 20 2.7.8 E-Cadherin 21 2.7.9 Zytokeratine 21 2.7.10 Vimentin 21 3 HUNDE, MATERIAL UND METHODEN 22 3.1 Patienten 22 3.2 Bioptate und Einschlusskriterien 23 3.3 Kontrolltiere 24 3.4 Immunhistochemische Untersuchungen 25 3.5 Auswertung der immunhistochemischen Reaktionen 28 3.6 Statistische Auswertung 29 4 ERGEBNISSE 31 4.1 Patienten 31 4.1.1 Signalement und Anamnese 31 4.1.2 Einteilung der Patienten in T-Kategorien 33 4.1.3 Histopathologische Befunde 34 4.1.4 Mediane Überlebenszeit nach endoskopisch interventioneller Zytoreduktion 34 4.1.5 Gesunde Kontrollgruppe 35 4.2 Ergebnisse der immunhistochemischen Untersuchungen 37 4.2.1 Kontrollen und Absorptionsreaktionen 37 4.2.2 Epidermal growth factor receptor (EGFR) 37 4.2.3 Vascular endothelial growth factor receptor-2 (VEGFR-2) 40 4.2.4 Cyclooxygenase-2 (COX-2) 42 4.2.5 p53 46 4.2.6 Ki-67 48 4.2.7 Aktivierte Caspase-3 50 4.2.8 Survivin 52 4.2.9 E-Cadherin 55 4.2.10 Zytokeratine 58 4.2.11 Vimentin 58 4.2.12 Bioptate von Tumorrezidiven 60 5 DISKUSSION 62 6 ZUSAMMENFASSUNG 84 7 SUMMARY 86 8 LITERATURVERZEICHNIS 88 9 ANHANG 105 9.1 Übersicht über die Hunde und Bioptate 105 9.2 Ergebnistabellen 107 9.3 Immunhistochemisches Reaktionsprotokoll 120 9.4 Ansatz der Lösungen und Puffer für die Immunhistochemie 122 9.5 Bezugsquellen für Geräte, Einmalartikel, Reagenzien und Chemikalien 123 9.6 Abbildungs- und Tabellenverzeichnis 125
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Analyse de trajectoires, perte d'autonomie et facteurs prédictifs : Modélisation de trajectoires / Trajectory analysis, loss of independence and predictive factors : Trajectory modeling

Bimou, Charlotte 09 October 2019 (has links)
La poursuite du rythme d’augmentation de l’espérance de vie des générations issue du baby-boom dans les pays développés serait souvent accompagnée de limitations fonctionnelles, d’incapacité, de plus en plus observées dans la population gériatrique. L'objectif général de cette thèse était de contribuer à la connaissance de l’évolution de l’autonomie fonctionnelle des personnes âgées dans une population hétérogène. Il s’agissait dans un premier temps d'identifier des groupes homogènes dans une population hétérogène de personnes âgées suivant la même trajectoire d'autonomie fonctionnelle sur une période de deux ans, ainsi que des facteurs prédictifs potentiels. Dans un second temps, d’analyser les conséquences cliniques des trajectoires et la survie des patients sur la même période d’observation. Le SMAF (Système de Mesure de l’Autonomie Fonctionnelle) et les échelles ADL (Activities of Daily Living) ont été employés comme indicateurs d’évaluation de l’autonomie. Dans ce contexte, des données de 221 patients issues de la cohorte UPSAV (Unité de Prévention, de Suivi et d’Analyse du Vieillissement) ont été exploitées. Nous avons employé trois méthodes d’analyse de trajectoires dont le GBTM (Group-Based Trajectory Modeling), k-means et classification ascendante hiérarchique. Les résultats ont révélé trois trajectoires distinctes d’autonomie fonctionnelle : stable, stable pendant un temps puis détériorée, continuellement altérée. Les facteurs prédictifs des trajectoires obtenus à l’aide de la régression logistique sont des critères socio-démographiques, médicaux et biologiques. Les personnes âgées affectées à la trajectoire de perte d’autonomie (trajectoire continuellement altérée) ont montré de fortes proportions de chutes dommageables. A partir d’un modèle de Cox, les troubles neurocognitifs, l’insuffisance cardiaque, la perte de poids involontaire et l’alcool ont été révélés comme facteurs prédictifs de la survenue du décès. On conclut de ces travaux que l’analyse longitudinale sur deux ans de suivi a permis de trouver des sous-groupes homogènes de personnes âgées en termes d’évolution de l’indépendance fonctionnelle. Quel que soit le niveau d’autonomie, la prévention de l’UPSAV devient utile même si le niveau d’utilité n’est pas le même. La prévention et le dépistage de la perte d’autonomie de la personne âgée suivie sur son lieu de vie doivent être anticipés afin de retarder la dégradation et maintenir l’autonomie à domicile. Des analyses ultérieures devraient s’intéresser à l’exploration de plus larges cohortes de personnes âgées pour confirmer et généraliser notre travail. / The increase in life expectancy of baby boom generations in developed countries would often be accompanied by functional limitations, disability, increasingly observed in the geriatric population. The general objective of this thesis was to contribute to the knowledge of the evolution of the functional independence of older people in a heterogeneous population. First, it was to identify homogeneous groups in a heterogeneous population of elderly people following the same functional independence trajectory over a two-year period, and potential predictive factors. Second, it was to analyze the clinical consequences of trajectories and patient survival over the same observation period. The SMAF (Système de Mesure de l'Autonomie Fonctionnelle) and ADL (Activities of Daily Living) scales were used as indicators for measuring independence. Analysis were performed from a sample of 221 patients of UPSAV (Unit for Prevention, Monitoring and Analysis of Aging) cohort. We used three methods including trajectory analysis including GBTM (Group-Based Trajectory Modeling), k-means and ascending hierarchical classification. The results suggest three distinct trajectories of functional independence: stable, stable then decline, continuously decline. The predictors of trajectories obtained using logistic regression are socio-demographic, medical and biological criteria. Patients assigned to the loss of independence trajectory (continuously altered trajectory) reported high proportions of injurious falls. Based on a Cox model, neurocognitive disorders, heart failure, involuntary weight loss and alcohol were revealed as predictors of death. We conclude from this work that the two-year longitudinal analysis identified homogeneous subgroups of elderly people in terms of changes in functional independence. The prevention of UPSAV becomes a useful even if the utility level is not the same. Prevention and screening of the loss of independence of the elderly person followed at home must be anticipated in order to delay the deterioration and to maintaining the autonomy. Future analyses should focus on exploring large cohorts of older people to confirm and generalize our research.

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