923 resultados para Wooffitt, Robin: Conversation analysis. Principles, practices and application
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Field lab: Business project
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Field lab: Business project
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RESUMO: Actualmente, a única possibilidade de cura para doentes com adenocarcinoma do pâncreas (PDAC) é a ressecção cirúrgica, no início deste estudo, perguntamo-nos se os predictores clínico-patológicos clássicos de prognostico poderiam ser validados em uma grande cohort de doentes com cancro do pâncreas ressecável e se outros predictores clínicos poderiam ter um papel na decisão de que doentes beneficiariam de ressecção cirúrgica. No capítulo 2, observamos que até 30% dos doentes morrem no primeiro ano após a ressecção cirúrgica, pelo que o nosso objectivo foi determinar factores pré-operatórios que se correlacionam com mortalidade precoce após ressecação cirúrgica com recurso a um instrumento estatisticamente validado, o Charlson-Age Comorbidity Index (CACI), determinamos que um CACI score superior a 4 foi preditivo de internamentos prolongados (p <0,001), complicações pós-operatórias (p = 0,042), e mortalidade em 1 ano pós- ressecção cirúrgica (p <0,001). Um CACI superior a 6 triplicou a mortalidade no primeiro ano pós-cirurgia e estes doentes têm menos de 50% de probabilidade de estarem vivos um ano após a cirurgia. No capítulo 3, o nosso objectivo foi identificar uma proteína de superfície que se correlacionasse estatisticamente com o prognostico de doentes com adenocarcinoma do pâncreas e permitisse a distinção de subgrupos de doentes de acordo com as suas diferenças moleculares, perguntamo-nos ainda se essa proteína poderia ser um marcador de células-estaminais. No nosso trabalho anterior observamos que as células tumorais na circulação sanguínea apresentavam genes com características bifenotípica epitelial e mesenquimal, enriquecimento para genes de células estaminais (ALDH1A1 / ALDH1A2 e KLF4), e uma super-expressão de genes da matriz extracelular (colagénios, SPARC, e DCN) normalmente identificados no estroma de PDAC. Após a avaliação dos tumores primários com RNA-ISH, muitos dos genes identificados, foram encontrados co-localizando em uma sub-população de células na região basal dos ductos pancreáticos malignos. Além disso, observamos que estas células expressam o marcador SV2A neuroendócrino, e o marcador de células estaminais ALDH1A1/2. Em comparação com tumores negativos para SV2, os doentes com tumores SV2 positivos apresentaram níveis mais baixos de CA 19-9 (69% vs. 52%, p = 0,012), tumores maiores (> 4 cm, 23% vs. 10%, p = 0,0430), menor invasão de gânglios linfáticos (69% vs. 86%, p = 0,005) e tumores mais diferenciados (69% vs. 57%, p = 0,047). A presença de SV2A foi associada com uma sobrevida livre de doença mais longa (HR: 0,49 p = 0,009) bem como melhor sobrevida global (HR: 0,54 p = 0,018). Em conjunto, esta informação aponta para dois subtipos diferentes de adenocarcinoma do pâncreas, e estes subtipos co-relacionam estatisticamente com o prognostico de doentes, sendo este subgrupo definido pela presença do clone celular SV2A / ALDH1A1/2 positivo com características neuroendócrinas. No Capítulo 4, a expressão de SV2A no cancro do pâncreas foi validado em linhas celulares primárias. Demonstramos a heterogeneidade do adenocarcinoma do pâncreas de acordo com características clonais neuroendócrinas. Ao comparar as linhas celulares expressando SV2 com linhas celulares negativas, verificamos que as linhas celulares SV2+ eram mais diferenciadas, diferindo de linhas celulares SV2 negativas no que respeita a mutação KRAS, proliferação e a resposta à quimioterapia. No capítulo 5, perguntamo-nos se o clone celular SV2 positivo poderia explicar a resistência a quimioterapia observada em doentes. Observamos um aumento absoluto de clones celulares expressando SV2A, em múltiplas linhas de evidência - doentes, linhas de células primárias e xenotransplantes. Embora, tenhamos sido capazes de demonstrar que o adenocarcinoma do pâncreas é uma doença heterogénea, consideramos que a caracterização genética destes clones celulares expressando SV2A é de elevada importância. Pretendemos colmatar esta limitação com as seguintes estratégias: Após o tratamento com quimioterapia neoadjuvante na nossa coorte, realizamos microdissecação a laser das amostras primarias em parafina, de forma a analisar mutações genéticas observadas no adenocarcinoma pancreático; em segundo lugar, pretendemos determinar consequências de knockdown da expressão de SV2A em nossas linhas celulares seguindo-se o tratamento com gemicitabina para determinação do papel funcional de SV2A; finalmente, uma vez que os nossos esforços anteriores com um promotor - repórter e SmartFlare ™ falharam, o próximo passo será realizar RNA-ISH PrimeFlow™ seguido de FACS e RNA-seq para caracterização deste clone celular. Em conjunto, conseguimos provar com várias linhas de evidência, que o adenocarcinoma pancreático é uma doença heterogénea, definido por um clone de células que expressam SV2A, com características neuroendócrinas. A presença deste clone no tecido de doentes correlaciona-se estatisticamente com o prognostico da doença, incluindo sobrevida livre de doença e sobrevida global. Juntamente com padrões de proliferação e co-expressão de ALDH1A1/2, este clone parece apresentar um comportamento de células estaminais e está associado a resistência a quimioterapia, uma vez que a sua expressão aumenta após agressão química, quer em doentes, quer em linhas de células primárias.----------------------------- ABSTRACT: Currently, the only chance of cure for patients with pancreatic adenocarcinoma is surgical resection, at the beginning of my thesis studies, we asked if the classical clinicopathologic predictors of outcome could be validated in a large cohort of patients with early stage pancreatic cancer and if other clinical predictors could have a role on deciding which patients would benefit from surgery. In chapter 2, we found that up to 30% of patients die within the first year after curative intent surgery for pancreatic adenocarcinoma. We aimed at determining pre-operative factors that would correlate with early mortality following resection for pancreatic cancer using a statistically validated tool, the Charlson-Age Comorbidity Index (CACI). We found that a CACI score greater than 4 was predictive of increased length of stay (p<0.001), post-operative complications (p=0.042), and mortality within 1-year of pancreatic resection (p<0.001). A CACI score of 6 or greater increased 3-fold the odds of death within the first year. Patients with a high CACI score have less than 50% likelihood of being alive 1 year after surgery. In chapter 3 we aimed at identifying a surface protein that correlates with patient’s outcome and distinguishes sub-groups of patients according to their molecular differences and if this protein could be a cancer stem cell marker. The most abundant class of circulating tumor cells identified in our previous work was found to have biphenotypic features of epithelial to mesenchymal transition, enrichment for stem-cell associated genes (ALDH1A1/ALDH1A2 and KLF4), and an overexpression of extracellular matrix genes (Collagens, SPARC, and DCN) normally found in the stromal microenvironment of PDAC primary tumors. Upon evaluation of matched primary tumors with RNA-ISH, many of the genes identified were found to co-localize in a sub-population of cells at the basal region of malignant pancreatic ducts. In addition, these cells expressed the neuroendocrine marker SV2A, and the stem cell marker ALDH1A1/2. Compared to SV2 negative tumors, patients with SV2 positive tumors were more likely to present with lower CA 19-9 (69% vs. 52%, p = 0.012), bigger tumors (size > 4 cm, 23% vs. 10%, p= 0.0430), less nodal involvement (69% vs. 86%, p = 0.005) and lower histologic grade (69% vs. 57%, p = 0.047). The presence of SV2A expressing cells was associated with an improved disease free survival (HR: 0.49 p=0.009) and overall survival (HR: 0.54 p=0.018) and correlated linearly with ALDH1A2. Together, this information points to two different sub-types of pancreatic adenocarcinoma, and these sub-types correlated with patients’ outcome and were defined by the presence of a SV2A/ ALDH1A1/2 expressing clone with neuroendocrine features. In Chapter 4, SV2A expression in cancer was validated in primary cell lines. We were able to demonstrate pancreatic adenocarcinoma heterogeneity according to neuroendocrine clonal features. When comparing SV2 expressing cell lines with SV2 negative cell lines, we found that SV2+ cell lines were more differentiated and differ from SV2 negative cell lines regarding KRAS mutation, proliferation and response to chemotherapy. In Chapter 5 we aimed at determining if this SV2 positive clone could explain chemoresistance observed in patients. We found an absolute increase in SV2A expressing cells, with multiple lines of evidence, in patients, primary cell lines and xenografts. Although, we have been able to show evidence that pancreatic adenocarcinoma is a heterogeneous disease, our findings warrant further investigation. To further characterize SV2A expressing clones after treatment with neoadjuvant chemotherapy in our cohort, we have performed laser capture microdissection of the paraffin embedded tissue in this study and will analyze the tissue for known genetic mutations in pancreatic adenocarcinoma; secondly, we want to know what will happen after knocking down SV2A expression in our cell lines followed by treatment with gemcitabine to determine if SV2A is functionally important; finally, since our previous efforts with a promoter – reporter and SmartFlare™ have failed, we will utilize a novel PrimeFlow™ RNA-ISH assay followed by FACS and RNA sequencing to further characterize this cellular clone. Overall our data proves, with multiple lines of evidence, that pancreatic adenocarcinoma is a heterogeneous disease, defined by a clone of SV2A expressing cells, with neuroendocrine features. The presence of this clone in patients’ tissue correlates with patient’s disease free survival and overall survival. Together with patterns of proliferation and ALDH1A1/2 co-expression, this clone seems to present a stem-cell-like behavior and is associated with chemoresistance, since it increases after chemotherapy, both in patients and primary cell lines.
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OBJECTIVE: Theoretical and empirical analysis of items and internal consistency of the Portuguese-language version of Social Phobia and Anxiety Inventory (SPAI-Portuguese). METHODS: Social phobia experts conducted a 45-item content analysis of the SPAI-Portuguese administered to a sample of 1,014 university students. Item discrimination was evaluated by Student's t test; interitem, mean and item-to-total correlations, by Pearson coefficient; reliability was estimated by Cronbach's alpha. RESULTS: There was 100% agreement among experts concerning the 45 items. On the SPAI-Portuguese 43 items were discriminative (p < 0.05). A few inter-item correlations between both subscales were below 0.2. The mean inter-item correlations were: 0.41 on social phobia subscale; 0.32 on agoraphobia subscale and 0.32 on the SPAI-Portuguese. Item-to-total correlations were all higher then 0.3 (p < 0.001). Cronbach's alphas were: 0.95 on the SPAI-Portuguese; 0.96 on social phobia subscale; 0.85 on agoraphobia subscale. CONCLUSION: The 45-item content analysis revealed appropriateness concerning the underlying construct of the SPAI-Portuguese (social phobia, agoraphobia) with good discriminative capacity on 43 items. The mean inter-item correlations and reliability coefficients demonstrated the SPAI-Portuguese and subscales internal consistency and multidimensionality. No item was suppressed in the SPAI-Portuguese but the authors suggest that a shortened SPAI, in its different versions, could be an even more useful tool for research settings in social phobia.
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Fusarium verticillioides is considered one of the most important global sources of fumonisin contamination in food and feed. Corn is one of the main commodities produced in the Northeastern Region of Brazil. The present study investigated potential mycotoxigenic fungal strains belonging to the F. verticillioides species isolated from corn kernels in 3 different Regions of the Brazilian State of Pernambuco. A polyphasic approach including classical taxonomy, molecular biology, MALDI-TOF MS and MALDI-TOF MS/MS for the identification and characterisation of the F. verticillioides strains was used. Sixty F. verticillioides strains were isolated and successfully identified by classical morphology, proteomic profiles of MALDI-TOF MS, and by molecular biology using the species-specific primers VERT-1 and VERT-2. FUM1 gene was further detected for all the 60 F. verticillioides by using the primers VERTF-1 and VERTF-2 and through the amplification profiles of the ISSR regions using the primers (GTG)5 and (GACA)4. Results obtained from molecular analysis shown a low genetic variability among these isolates from the different geographical regions. All of the 60 F. verticillioides isolates assessed by MALDI-TOF MS/MS presented ion peaks with the molecular mass of the fumonisin B1 (721.83 g/mol) and B2 (705.83 g/mol)
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Recently, there has been a growing interest in the field of metabolomics, materialized by a remarkable growth in experimental techniques, available data and related biological applications. Indeed, techniques as Nuclear Magnetic Resonance, Gas or Liquid Chromatography, Mass Spectrometry, Infrared and UV-visible spectroscopies have provided extensive datasets that can help in tasks as biological and biomedical discovery, biotechnology and drug development. However, as it happens with other omics data, the analysis of metabolomics datasets provides multiple challenges, both in terms of methodologies and in the development of appropriate computational tools. Indeed, from the available software tools, none addresses the multiplicity of existing techniques and data analysis tasks. In this work, we make available a novel R package, named specmine, which provides a set of methods for metabolomics data analysis, including data loading in different formats, pre-processing, metabolite identification, univariate and multivariate data analysis, machine learning, and feature selection. Importantly, the implemented methods provide adequate support for the analysis of data from diverse experimental techniques, integrating a large set of functions from several R packages in a powerful, yet simple to use environment. The package, already available in CRAN, is accompanied by a web site where users can deposit datasets, scripts and analysis reports to be shared with the community, promoting the efficient sharing of metabolomics data analysis pipelines.
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OBJECTIVE: To test the hypothesis that short periods of ischemia may increase the myocardial protection obtained with intermittent crossclamping of the aorta. METHODS: In the control group (18 patients), surgery was performed with systemic hypothermia at 32ºC and intermittent crossclamping of the aorta. Extracorporeal circulation was used. In the preconditioning group (17 patients), 2 crossclampings of the aorta lasting 3min each were added prior to the intermittent crossclamping of the conventional technique with an interval of 2min of reperfusion between them. Blood samples for analyses of pH, pCO2, pO2, sodium, potassium, calcium, and magnesium were obtained from the coronary sinus at the beginning of extracorporeal circulation (time 1), at the end of the first anastomosis (time 2), and at the end of extracorporeal circulation (time 3). RESULTS: No difference was observed in the results of the 2 groups, except for a variation in the ionic values in the different times of blood withdrawal; sodium values, however, remained stable. All patients had a good clinical outcome. CONCLUSION: The results of intermittent crossclamping of the aorta with moderate hypothermia were not altered by the use of ischemic preconditioning.
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Currently, prebiotics are all carbohydrates of relatively short chain length. An important group is the fructooligosaccharides, which are a special kind of prebiotics associated to their selective stimulation of the activity of certain groups of colonic bacteria that have a positive and beneficial effect on intestinal microbiota, reducing incidence of gastrointestinal infections, respiratory and also possessing a recognized bifidogenic effect. Traditionally, these prebiotic compounds have been obtained through extraction processes from some plants, as well as through enzymatic hydrolysis of sucrose. However, different fermentative methods have also been proposed for the production of fructooligosaccharides, such as solid-state fermentation utilizing various agroindustrial by-products. By optimizing the culture parameters, fructooligosaccharides yields and productivity can be improved. The use of immobilized enzymes and cells has also been proposed as being an effective and economic method for large-scale production of fructooligosaccharides. This paper is an overview on the results of recent studies on fructooligosacharides biosynthesis, physicochemical properties, sources, biotechnological production and applications.
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La verificación y el análisis de programas con características probabilistas es una tarea necesaria del quehacer científico y tecnológico actual. El éxito y su posterior masificación de las implementaciones de protocolos de comunicación a nivel hardware y soluciones probabilistas a problemas distribuidos hacen más que interesante el uso de agentes estocásticos como elementos de programación. En muchos de estos casos el uso de agentes aleatorios produce soluciones mejores y más eficientes; en otros proveen soluciones donde es imposible encontrarlas por métodos tradicionales. Estos algoritmos se encuentran generalmente embebidos en múltiples mecanismos de hardware, por lo que un error en los mismos puede llegar a producir una multiplicación no deseada de sus efectos nocivos.Actualmente el mayor esfuerzo en el análisis de programas probabilísticos se lleva a cabo en el estudio y desarrollo de herramientas denominadas chequeadores de modelos probabilísticos. Las mismas, dado un modelo finito del sistema estocástico, obtienen de forma automática varias medidas de performance del mismo. Aunque esto puede ser bastante útil a la hora de verificar programas, para sistemas de uso general se hace necesario poder chequear especificaciones más completas que hacen a la corrección del algoritmo. Incluso sería interesante poder obtener automáticamente las propiedades del sistema, en forma de invariantes y contraejemplos.En este proyecto se pretende abordar el problema de análisis estático de programas probabilísticos mediante el uso de herramientas deductivas como probadores de teoremas y SMT solvers. Las mismas han mostrado su madurez y eficacia en atacar problemas de la programación tradicional. Con el fin de no perder automaticidad en los métodos, trabajaremos dentro del marco de "Interpretación Abstracta" el cual nos brinda un delineamiento para nuestro desarrollo teórico. Al mismo tiempo pondremos en práctica estos fundamentos mediante implementaciones concretas que utilicen aquellas herramientas.
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La Enfermedad de Chagas es una de las principales endemias de América Latina donde existen cerca de 18 millones de infectados y 90 millones en riesgo. Entre el 25 y el 30 por ciento desarrolla patología cardíaca o digestiva en el período crónico. Se ha postulado que mecanismos autoinmunes, sumados a la acción directa del parásito, podrían estar involucrados en la patogenia de la enfermedad. El desarrollo de vacunas tradicionales en Enfermedad de Chagas es una meta difícil de alcanzar, por lo cual parece más factible abordar estrategias basadas en la inmunomodulación, para disminuir la carga parasitaria, minimizar las acciones deletéreas en el periodo agudo y prevenir el desarrollo de patología en la etapa crónica. Para ello es necesario avanzar en el conocimiento de los mecanismos involucrados en la protección y en la patogenia. Si se acepta la hipótesis autoinmune, una estrategia de vacunación con un tripanosoma antigénicamente similar al T. cruzi pero no patógeno podría evitar posibles mecanismos autoagresivos. En nuestro Laboratorio se ha empleado un modelo de vacunación en ratones utilizando como inmunógeno el Trypanosoma rangeli, no patógeno en humanos. Los ratones vacunados, infectados con T. cruzi, mostraron buena respuesta inmune celular y humoral, bajas parasitemias, ausencia de lesiones histológicas, y sobrevida cercana al 100 por ciento. Los controles no vacunados tuvieron una elevada mortalidad. Debido al ciclo biológico del parásito, la defensa efectiva contra el T. cruzi requiere una potente respuesta de anticuerpos contra las formas extracelulares y una eficaz respuesta celular contra los amastigotes intracelulares. En el modelo desarrollado en nuestro laboratorio la protección se asocia con un adecuado equilibrio entre respuesta TH1 y TH2, con leve predominio TH1, disminución de citoquinas (Ck) proinflamatorias e incremento de receptores solubles de Ck. El esquema de inmunización demostró asimismo su eficacia en cobayos y en perros mantenidos en el Laboratorio. Hipótesis de trabajo: - La vacunación con T. rangeli desencadena mecanismos inmunomodulatorios que protegen de la infección con T. cruzi, entre los cuales se encuentran eventos que actúan tempranamente en el sitio de inoculación y en los que están involucradas células y moléculas del sistema inmune innato. - La vacunación a perros constituye una nueva herramienta en la lucha contra la Enfermedad de Chagas. Objetivos: i) profundizar el estudio tendiente a dilucidar los mecanismos involucrados en la resistencia inducida por la inmunización con T. rangeli en ratones; ii) estudiar el efecto que tiene el estrés físico de los ratones sobre la eficacia de la vacunación y iii) analizar la inmunogenicidad de la vacuna en perros de zonas endémicas para Enfermedad de Chagas. Material y metodos: Los ratones y perros serán vacunados con tres dosis de epimastigotes de T. rangeli, fijados con glutaraldehido y los controles solo recibirán PBS. Los ratones seran desafiados con T. cruzi. Se estudiará en liquido peritoneal: a) poblaciones celulares por Citometria de flujo; b) cuantificación de los distintos tipos de inmunoglobulinas, de citoquinas y sus receptores solubles, por ELISA, c) ON y arginasa, por técnicas colorimetricas; d) est.udio de la interacción macrófago-parásito y de receptores celulares por Inmunofluorescencia. e) En perros, se realizarán estudios parasitológicos (xenodiagnostico) y serológicos en vacunados y controles, 12 y 24 meses post vacunación. Resultados esperados e importancia del proyecto: se espera conocer los principales eventos tempranos que participan en la eliminación de los parásitos en los animales vacunados, el efecto del stress sobre la vacunación y asimismo, la inmunogenicidad de la vacuna en perros de campo. Todo ello permitirá obtener información sobre la eficacia de la vacunación experimental y podría aportar una herramienta adicional contra la Enfermedad de Chagas, interfiriendo en la cadena epidemiológica en áreas endémicas.
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Visualistics, computer science, picture syntax, picture semantics, picture pragmatics, interactive pictures
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Reaction separation processes, reactive distillation, chromatographic reactor, equilibrium theory, nonlinear waves, process control, observer design, asymptoticaly exact input/output-linearization
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Abstract Background: Due to the importance of coronary artery disease (CAD), continuous investigation of the risk factors (RFs) is needed. Objective: To evaluate the prevalence of RFs for CAD in cities in Rio Grande do Sul State, and compare it with that reported in a similar study conducted in the same cities in 2002. Methods: Cross-sectional study on 1,056 healthy adults, investigating the prevalence and absolute and relative frequencies of the following RFs for CAD: obesity, systemic arterial hypertension (SAH), dyslipidemias, smoking, sedentary lifestyle, diabetes mellitus, and family history, as well as age and sex. Data was collected in 19 cities, host of the Offices of the Regional Coordinators of Health, as in the 2002 study. Results: Twenty-six percent of the sample consisted of older adults and 57% were women. The prevalence of sedentary lifestyle was 44%, history family 50%, smoking 23%, overweight/obesity 68%, dyslipidemia (high cholesterol levels) 43%, SAH 40%, and diabetes 11%. When compared to the 2002 study, the prevalence of active smoking and sedentary behavior decreased, whereas the prevalence of hypertension, dyslipidemia and obesity increased. Obesity is the most prevalent RF in women, and SAH the most prevalent in men. Conclusions: The prevalence of RFs for CAD in Rio Grande do Sul State remains high. Hypertension, obesity and dyslipidemia are still prevalent and require major prevention programs. Smoking and physical inactivity have decreased in the state, suggesting the efficacy of related campaigns.
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Magdeburg, Univ., Fak. für Elektrotechnik und Informationstechnik, Diss., 2010
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Magdeburg, Univ., Fak. für Wirtschaftswiss., Diss., 2013