979 resultados para VE-cadhérines
Resumo:
AIMS: To assess quantitatively variations in the extent of capillary basement membrane (BM) thickening between different retinal layers and within arterial and venous environments during diabetes.
METHODS: One year after induction of experimental (streptozotocin) diabetes in rats, six diabetic animals together with six age-matched control animals were sacrificed and the retinas fixed for transmission electron microscopy (TEM). Blocks of retina straddling the major arteries and veins in the central retinal were dissected out, embedded in resin, and sectioned. Capillaries in close proximity to arteries or veins were designated as residing in either an arterial (AE) or a venous (VE) environment respectively, and the retinal layer in which each capillary was located was also noted. The thickness of the BM was then measured on an image analyser based two dimensional morphometric analysis system.
RESULTS: In both diabetics and controls the AE capillaries had consistently thicker BMs than the VE capillaries. The BMs of both AE and VE capillaries from diabetics were thicker than those of capillaries in the corresponding retinal layer from the normal rats (p < or = 0.005). Also, in normal AE and VE capillaries and diabetic AE capillaries the BM in the nerve fibre layer (NFL) was thicker than that in either the inner (IPL) or outer (OPL) plexiform layers (p < or = 0.001). However, in diabetic VE capillaries the BMs of capillaries in the NFL were thicker than those of capillaries in the IPL (p < or = 0.05) which, in turn, had thicker BMs than capillaries in the OPL (p < or = 0.005).
CONCLUSIONS: The variation in the extent of capillary BM thickening between different retinal layers within AE and VE environments may be related to differences in levels of oxygen tension and oxidative stress in the retina around arteries compared with that around veins.
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I have completed 80% of a teaching text book (text and graphics) on Separation Science and Technology - Theory. The book's content is what I've learned over many years of practice and teaching with an emphasis on clarifying and explaining the nuances within the theories associated with various practical approaches to chemical and biochemical separations.
The book is divided into self-contained Chapters with many worked examples and practice questions. It very much aligns with my teaching on CHM3005D, CHM2010, CHM2007 and is ideal for PMY8105 and the new proposed MSci in Analytical Chemistry Programme. The book brings together diverse material in single space and will be a valuable pedagogical resource for the teaching of this key discipline within QUB and elsewhere.
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El proceso de transición del familiar, a cuidador de la persona con depresión Método: diseño de la investigación es de naturaleza cualitativa y inductiva, usando la Teoría Fundamentada. Investigación tuvo lugar en 2 polos de las consultas externas del Departamento de Psiquiatría y Salud Mental, Hospital de Évora, Portugal, en 2 ciudades diferentes, durante Febrero y Julio, 2009. La selección de participantes se hizo mediante la muestra no probabilística intencional de acuerdo con los criterios: adulto y/o anciano con un diagnóstico clínico de reacción depresiva breve o prolongada (CIE-9); vivir con familiares; capacidad cognitiva para permitir la recogida de datos; participación voluntaria del paciente y su familia. Se realizaron entrevistas narrativas semiestructuradas a 8 familias, correspondientes a 20 participantes. Resultados: la codificación axial nos permitió identificar 2 categorías: 1ª- narrativa de la enfermedad (inicio, causas, manifestaciones y la caracterización de la depresión). El inicio es identificado por la familia y el paciente, mientras que las causas se identifican sólo por el paciente. Para el familiar la depresión se manifiesta por comportamientos agresivos, aislamiento, desinversión y pasividad; para el paciente, se manifiesta por señales somáticas, pérdida de la voluntad, tristeza, miedo y aislamiento. Para el familiar es una cosa mala porque destruye las relaciones familiares y manipuladora porque es una manera de conseguir lo que el paciente quiere; para el paciente es una cosa de la cabeza, que no se ve, es inconstante y cambia a la persona. 2ª- estrategias de cuidado (escape, indiferencia, conflicto, chantaje).Como manera de cuidar, el familiar está menos tiempo en el hogar para evitar conflictos, aumenta el consumo de alcohol como vía de escape, ignora la conducta del paciente para no molestarlo, como una forma de estimular exige que el paciente haga actividades, y niega actividades sociales si el paciente no lo acompaña, para que él se aísle menos. A veces responsabiliza al paciente por la inestabilidad de la familia, intentando así ayudarle a ser consciente de su comportamiento. No participa en las consultas médicas para que el paciente se sienta más cómodo y rara vez participa en las tareas del hogar, también para que el paciente haga alguna actividad. Discusión: de alguna manera los familiares cambian, para atender a las necesidades del paciente y el papel de cuidador se construye cada día en la interacción entre las personas que cohabitan, de modo que el cuidado tendrá características particulares. Todo lo que el familiar hace, tiene la intención de ayudar al paciente a mejorar y superar su depresión a través de un modo diferente de cuidado. Algunas veces hay un sentimiento de culpa, como consecuencia no de haber cometido una mala acción, sino por haber tenido un comportamiento más duro con el paciente y no saber se eso es lo correcto. Así, es muy importante la intervención de enfermería para que los cuidadores reciban orientaciones y apoyo y la transición se haga armoniosamente.
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Objetivos - Caracterizar la depresión en la perspectiva de quien la vive; - Caracterizar el papel del cuidador familiar en la perspectiva del paciente; - Describir las reacciones del paciente en la relación con los cuidadores familiares. Método: diseño de la investigación es de naturaleza cualitativa y inductiva, usando la Teoría Fundamentada. La investigación tuvo lugar en 2 polos de las consultas externas del Departamento de Psiquiatría y Salud Mental, Hospital de Évora, Portugal, en 2 ciudades diferentes, durante Febrero y Julio, 2009. La selección de participantes se hizo mediante la muestra no probabilista intencional de acuerdo con los criterios: ser adulto y/o anciano con un diagnóstico clínico de depresión; vivir con familiares en su casa; tener capacidad cognitiva para permitir la recogida de datos; participación voluntaria del paciente en el estudio. Se realizaron entrevistas narrativas semiestructuradas a 8 pacientes, 1 hombre y 7 mujeres. Resultados: la codificación axial nos permitió identificar 4 categorías: - 1ª narrativa del proceso de enfermar-se - tiene múltiples facetas, con una clara identificación del comienzo, causas (acontecimientos de vida, actividad laboral, conflictos familiares), características (es inconstante, no se ve pero cambia la persona, es una enfermedad de la cabeza) y manifestaciones de la enfermedad (somáticas y del comportamiento, alteraciones de las actividades de vida); - 2ª la depresión y yo - la relación dual entre el paciente y la depresión, las estrategias para hacer frente a la enfermedad, el auto-aprendizaje, la búsqueda de ayuda, la gestión de la medicación, los sentimientos, los deseos; - 3ª leer el familiar que cuida - la interpretación y el significado atribuido por el paciente al comportamiento del cuidador; el sentimiento de no sentirse cuidado, la falta de comprensión y paciencia, el chantaje emocional, las amenazas, la agresión verbal, la indiferencia, la falta de diálogo, el control excesivo, la incapacidad para escuchar, las tentativas fracasadas para ayudar; - 4ª-Yo, y la relación con el familiar cuidador - el paciente no reconoce la capacidad al familiar para ayudar, ignora sus consejos y opiniones y se siente perdido y sin saber qué hacer, evita el dialogo y se aísla o sale de casa por períodos, no comprende el familiar, ni sabe lo que el piensa acerca de su situación de salud, se siente solo. Discusión: la relación entre el paciente y la depresión es muy intimista, cerrada y el familiar no hace parte de ella. El paciente no comprende el familiar, pero el familiar también no comprende el paciente. Entre el paciente y el familiar hay una brecha y el paciente no reconoce el familiar como elemento importante en su recuperación, no le reconoce capacidad ni competencia. Entonces, la enfermera tiene un papel fundamental como mediadora, no solo en el conflicto, pero también en la enseñanza de estrategias de comunicación y a través de la enseñanza de lo que es la depresión, sus manifestaciones, tratamiento y su pronóstico. Si la enfermera conocer las dificultades del paciente y sus sentimientos hacia el familiar cuidador, podrá intervenir y planear juntamente con el paciente y su familiar, intervenciones psicosociales que contribuyan para el bien estar de la familia, de modo a que el hogar sea un espacio terapéutico
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A problemática que constitui o ponto de partida do presente estudo evidencia a importância de se conhecer e compreender a forma como se processa a inserção profissional dos recém-diplomados em Ensino Básico - 1º Ciclo. De entre distintas ópticas possíveis, considerou-se importante assumir, como elemento estratégico deste processo, e na linha do pensamento de M. Alves (2001), o entendimento de que o processo de inserção profissional assume um carácter dinâmico, que envolve três actores fundamentais: os diplomados, os empregadores e os estabelecimentos de ensino superior. É tendo como base de trabalho esta perspectiva (conceito de inserção profissional articulado com o paradigma da aprendizagem ao longo da vida) que se edifica o presente estudo, estruturando-se em quatro partes. A primeira delas visa, embora não de forma exclusiva, a explanação dos principais referenciais teóricos relativos à temática em questão; a segunda parte explicita as opções metodológicas adoptadas; a terceira debruça-se sobre a análise e interpretação dos resultados e a quarta remete para algumas conclusões que emergiram de todo o processo de investigação empreendido. Procurando desenvolver-se uma investigação descritiva assente numa metodologia integrada e complementar com abordagens qualitativas e quantitativas, a recolha de dados incide num questionário e numa entrevista, tendo-se sempre em consideração os objectivos subjacentes ao estudo e optando-se, para tal, como sujeitos, pelos licenciados em Ensino Básico - 1.° Ciclo que realizaram a sua formação nas instituições formadoras do Alentejo (Escolas Superiores de Beja e Portalegre e Universidade de Évora), no período compreendido entre 2001 e 2003. As trajectórias profissionais destes licenciados ficam marcadas por sentimentos de ilusão, incerteza e indignação, mas também por um forte sentimento de frustração. Não foi pacífico, para muitos deles, aceitar que a realização do curso não lhes conferiu o acesso ao emprego esperado. A sua maioria encontrava-se integrada em sectores profissionais que não estavam directamente relacionados com o curso ou, então, permaneciam desempregados. A esperança de virem a exercer a profissão docente parecia ser cada vez mais ténue. /***Abstract - The problem that constitutes the start of the present study emphasizes the importance of knowing and understanding the way it proceeds the professional insertion of the new graduates of the Ensino Básico — V Ciclo (primary school).Between several visions, it has been important, as a strategic element of this process and following the line of M. Alves (2001), the understanding that the professional insertion assumes a dynamic character, that envolves three fundamental elements: the graduates, the employers and. the universities. This study, structured in four parts, is based in the concept that links profession insertion with life long learning. The purpose of the first part is to expose, not in an exclusive way, the several theories connected with the theme in question the second part explains the methodology used; the third consists of the analysis and interpretation of the results and the fourth and. last one, exposes some conclusions that carne out of the investigation process. It has been tried in this study to develop a descriptive investigation, based on an integrated and complementary methodology that includes a qualitative and quantitative analysis. Therefore, the gathering of data is based on a questionnaire and an interview. Always considering the underlying objectives of the study, we have chosen, as subjects, the graduates in Ensino Básico - 1º Ciclo that performed their formation in the institutes of Alentejo (Escola Superior de Educação de Beja, Escola Superior de Educação de Portalegre e Universidade de Évora), in the period between 2001 and. 2003. The professional trajectory of these graduates is full of uncertainty, indignation and also full of strong feelings of frustration. It was not easy for many of them to accept that the course they have completed doesn't open the doors for the job they've dreamed of and expected. The majority was integrated in professional areas not directly connected with their course or then remained unemployed. The hope of becoming teachers was turning more and more tenuous.
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Coronary CT angiography is widely used in clinical practice for the assessment of coronary artery disease. Several studies have shown that the same exam can also be used to assess left ventricle (LV) function. LV function is usually evaluated using just the data from end-systolic and end-diastolic phases even though coronary CT angiography (CTA) provides data concerning multiple cardiac phases, along the cardiac cycle. This unused wealth of data, mostly due to its complexity and the lack of proper tools, has still to be explored in order to assess if further insight is possible regarding regional LV functional analysis. Furthermore, different parameters can be computed to characterize LV function and while some are well known by clinicians others still need to be evaluated concerning their value in clinical scenarios. The work presented in this thesis covers two steps towards extended use of CTA data: LV segmentation and functional analysis. A new semi-automatic segmentation method is presented to obtain LV data for all cardiac phases available in a CTA exam and a 3D editing tool was designed to allow users to fine tune the segmentations. Regarding segmentation evaluation, a methodology is proposed in order to help choose the similarity metrics to be used to compare segmentations. This methodology allows the detection of redundant measures that can be discarded. The evaluation was performed with the help of three experienced radiographers yielding low intraand inter-observer variability. In order to allow exploring the segmented data, several parameters characterizing global and regional LV function are computed for the available cardiac phases. The data thus obtained is shown using a set of visualizations allowing synchronized visual exploration. The main purpose is to provide means for clinicians to explore the data and gather insight over their meaning, as well as their correlation with each other and with diagnosis outcomes. Finally, an interactive method is proposed to help clinicians assess myocardial perfusion by providing automatic assignment of lesions, detected by clinicians, to a myocardial segment. This new approach has obtained positive feedback from clinicians and is not only an improvement over their current assessment method but also an important first step towards systematic validation of automatic myocardial perfusion assessment measures.
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Studies with computer-experienced children in the UK and less experienced in Ukraine explored the potential for VEs in teaching historical chronology to middle-school children aged 10–12 years old. Active fly-through VEs had been previously used successfully with primary school children aged 8–9 years old (given specific training with the environment) when they were subsequently tested for their ability to order events chronologically. All VEs in the present studies included a training element and active challenge, both found previously to enhance learning in other age groups. Ukraine children were trained and tested. UK children here were trained and tested, then retrained and retested to examine savings. Unlike other age groups, no significant benefit was seen for VE training compared with PowerPoint and Text conditions in either study. Possible explanations for the ineffectiveness of VE training for children of middle school age will be discussed. Keywords: timeline, chronographics
Resumo:
Historical time and chronological sequence are usually conveyed to pupils via the presentation of semantic information on printed worksheets, events being rote-memorised according to date. We explored the use of virtual environments in which successive historical events were depicted as “places” in time–space, encountered sequentially in a fly-through. Testing was via “Which came first, X or Y?” questions and picture-ordering. University undergraduates experiencing the history of an imaginary planet performed better after a VE than after viewing a “washing line” of sequential images, or captions alone, especially for items in intermediate list positions. However, secondary children 11–14 years remembered no more about successive events in feudal England when they were presented virtually compared with either paper picture or 2-D computer graphic conditions. Primary children 7–9 years learned more about historical sequence after studying a series of paper images, compared with either VE or computer graphic conditions, remembering more in early/intermediate list positions. Reasons for the discrepant results are discussed and future possible uses of VEs in the teaching of chronology assessed. Keywords: timeline, chronographics
Resumo:
Studies examined the potential use of Virtual Environments (VEs) in teaching historical chronology to 127 children of primary school age (8–9 years). The use of passive fly-through VEs had been found, in an earlier study, to be disadvantageous with this age group when tested for their subsequent ability to place displayed sequential events in correct chronological order. All VEs in the present studies included active challenge, previously shown to enhance learning in older participants. Primary school children in the UK (all frequent computer users) were tested using UK historical materials, but no significant effect was found between three conditions (Paper, PowerPoint and VE) with minimal pre-training. However, excellent (error free) learning occurred when children were allowed greater exploration prior to training in the VE. In Ukraine, with children having much less computer familiarity, training in a VE (depicting Ukrainian history) produced better learning compared to PowerPoint, but no better than in a Paper condition. The results confirmed the benefit of using challenge in a VE with primary age children, but only with adequate prior familiarisation with the medium. Familiarity may reduce working memory load and increase children’s spatial memory capacity for acquiring sequential temporal-spatial information from virtual displays. Keywords: timeline, chronographics
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A series of experiments is described, evaluating user recall of visualisations of historical chronology. Such visualisations are widely created but have not hitherto been evaluated. Users were tested on their ability to learn a sequence of historical events presented in a virtual environment (VE) fly-through visualisation, compared with the learning of equivalent material in other formats that are sequential but lack the 3D spatial aspect. Memorability is a particularly important function of visualisation in education. The measures used during evaluation are enumerated and discussed. The majority of the experiments reported compared three conditions, one using a virtual environment visualisation with a significant spatial element, one using a serial on-screen presentation in PowerPoint, and one using serial presentation on paper. Some aspects were trialled with groups having contrasting prior experience of computers, in the UK and Ukraine. Evidence suggests that a more complex environment including animations and sounds or music, intended to engage users and reinforce memorability, were in fact distracting. Findings are reported in relation to the age of the participants, suggesting that children at 11–14 years benefit less from, or are even disadvantaged by, VE visualisations when compared with 7–9 year olds or undergraduates. Finally, results suggest that VE visualisations offering a ‘landscape’ of information are more memorable than those based on a linear model. Keywords: timeline, chronographics
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Gonadotrophin-releasing hormone (GnRH) is the main neurohormone controlling gonadotrophin release in all vertebrates, and in teleost fish also of growth hormone and possibly of other adenohypophyseal hormones. Over 20 GnRHs have been identified in vertebrates and protochoordates and shown to bind cognate G-protein couple receptors (GnRHR). We have searched the puffer fish, Fugu rubripes, genome sequencing database, identified five GnRHR genes and proceeded to isolate the corresponding complementary DNAs in European sea bass, Dicentrachus labrax. Phylogenetic analysis clusters the European sea bass, puffer fish and all other vertebrate receptors into two main lineages corresponding to the mammalian type I and II receptors. The fish receptors could be subdivided in two GnRHR1 (A and B) and three GnRHR2 (A, B and C) subtypes. Amino acid sequence identity within receptor subtypes varies between 70 and 90% but only 50–55% among the two main lineages in fish. All European sea bass receptor mRNAs are expressed in the anterior and mid brain, and all but one are expressed in the pituitary gland. There is differential expression of the receptors in peripheral tissues related to reproduction (gonads), chemical senses (eye and olfactory epithelium) and osmoregulation (kidney and gill). This is the first report showing five GnRH receptors in a vertebrate species and the gene expression patterns support the concept that GnRH and GnRHRs play highly diverse functional roles in the regulation of cellular functions, besides the ‘‘classical’’ role of pituitary function regulation.
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Les plus récentes études sur l'auteur se sont intéressées à plusieurs aspects de sa figure. Elles ont questionné ses représentations dans la fiction. Elles l'ont étudiée comme une fabrication du champ littéraire. Elles ont réfléchi aux croyances et aux mythes dont cette image est porteuse. Elles se sont penchées sur le rapport que les lecteurs entretiennent avec la biographie de l'auteur. Elles ont même cherché à comprendre à quelles conditions un individu en arrive à se dire écrivain. Aucune étude ne s'est toutefois intéressée à la conservation posthume des figures d'auteur par ces fascinants musées que constitue leur maison personnelle, lorsqu'elle est ouverte au public.Dans une perspective chronologique, le premier objectif de la Thèse consiste à situer et à comparer les maisons d'écrivains en France et au Québec. Dans une perspective synchronique, le deuxième objectif est d'étudier les représentations des écrivains que les maisons-musées véhiculent.L'ouverture des premières maisons d'hommes célèbres en Europe à la fin du XIXe siècle est tributaire du culte des grands hommes. La première partie de la Thèse est consacrée à ce phénomène, notamment étudié par Jean-Claude Bonnet. En France, les maisons-musées gagnent en popularité tout au long du XXe siècle et connaissent un âge d'or dans les années 1980 et 1990, sous le coup de politiques gouvernementales qui témoignent désormais d'une conception élargie de la culture. Au Québec, l'émergence du phénomène n'est pas beaucoup plus tardive, mais connait une expansion beaucoup moins importante. La deuxième partie de la Thèse s'intéresse aux politiques culturelles qui favorisent l'ouverture au public de maisons d'écrivains dans ces pays de la Francophonie. Elle présente également les monographies des six maisons d'écrivains qui composent le corpus restreint de la Thèse : en France, la Maison de Balzac à Paris, la Maison de Tante Léonie-Musée Marcel-Proust à Illiers-Combray et la Maison Elsa-Triolet-Aragon à Saint-Amoult-en-Yvelines; au Québec, la Maison Samuel-Bédard-Musée Louis-Hémon à Péribonka, l'Espace Félix-Leclerc à l'île d'Orléans et l'Espace Claude-Henri-Grignon à Saint-Jérome. Enfin, la troisième partie de la Thèse porte sur les représentations des écrivains dans les maisons d'écrivains, en s'intéressant à une particularité importante de ces lieux semi-privés et semi-publics : l'opposition entre familiarité et grandeur sur laquelle ils reposent.
Resumo:
Cet essai propose une trousse d’enseignement pour un cours de chimie organique intégrant l’environnement au niveau collégial. Une exploration des concepts théoriques de différentes disciplines : l’enseignement au collégial, les courants pédagogiques et programmes, la chimie verte, les questions scientifiques sociales vives, l’alphabétisation scientifique et les efforts environnementaux dans les institutions, permet de concevoir une trousse fonctionnelle. La trousse se veut un outil adaptable selon les besoins de ses utilisateurs pour aider les nouveaux professeurs à intégrer des concepts environnementaux dans un cours existant.
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Cardiogenesis is a delicate and complex process that requires the coordination of an intricate network of pathways and the different cell types. Therefore, understanding heart development at the morphogenetic level is an essential requirement to uncover the causes of congenital heart disease and to provide insight for disease therapies. Mouse Cerberus like 2 (Cerl2) has been defined as a Nodal antagonist in the node with an important role in the Left-Right (L/R) axis establishment, at the early embryonic development. As expected, Cerl2 knockout mice (Cerl2-/-) showed multiple laterality defects with associated cardiac failure. In order to identify the endogenous role of Cerl2 during heart formation independent of its described functions in the node, we accurately analyzed animals where laterality defects were not present. We thereby unravel the consequences of Cerl2 lossof- function in the heart, namely increased left ventricular thickness due to hyperplasia of cardiomyocytes and de-regulated expression of cardiac genes. Furthermore, the Cerl2 mutant neonates present impaired cardiac function. Once that the cardiac expression of Cerl2 is mostly observed in the left ventricle until around midgestration, this result suggest a specific regulatory role of Cerl2 during the formation of the left ventricular myoarchitecture. Here, we present two possible molecular mechanisms underlying the cardiac Cerl2 function, the regulation of Cerl2 antagonist in activation of the TGFßs/Nodal/Activin/Smad2 signaling identified by increased Smad2 phosphorilation in Cerl2-/- hearts and the negative feedback between Cerl2 and Wnt/ß-catenin signaling in heart formation. In this work and since embryonic stem cells derived from 129 mice strain is extensively used to produce targeted mutants, we also present echocardiographic reference values to progressive use of juveniles and young adult 129/Sv strain in cardiac studies. In addition, we investigate the cardiac physiology of the surviving Cerl2 mutants in 129/Sv background over time through a follow-up study using echocardiographic analysis. Our results revealed that Cerl2-/- mice are able to improve and maintain the diastolic and most of systolic cardiac physiologic parameters as analyzed until young adult age. Since Cerl2 is no longer expressed in the postnatal heart, we suggest that an intrinsic and compensatory mechanism of adaptation may be active for recovering the decreased cardiac function found in Cerl2 mutant neonates. Altogether, these data highlight the role of Cerl2 during embryonic heart development in mice. Furthermore, we also suggest that Cerl2-/- may be an interesting model to uncover the molecular, cellular and physiological mechanisms behind the improvement of the cardiac function, contributing to the development of therapeutic approaches to treat heart failures.
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Tese de mestrado, Ciências da Educação (Tecnologias Educativas), Universidade de Lisboa, Instituto de Educação, 2010