LISA (Laser Interferometer Space Antenna) ist ein geplanter Gravitationswellendetektor, der aus drei Satelliten bestehen soll, deren Abstand mit Hilfe von Laserinterferometrie überwacht wird. Die hohe Frequenzstabilität der Laser, die dafür benötigt wird, soll mit einem dreistufigen Verfahren erreicht werden. Dieses beinhaltet eine Vorstabilisierung, die nicht nur hohe Stabilität sondern auch Durchstimmbarkeit aufweisen muss. Eine Möglichkeit so eine durchstimmbare Vorstabilisierung zu realisieren ist die Verwendung eines optischen Resonators mit eingebautem Piezoaktuator. Dies ist an sich kein neuer Ansatz, wurde bisher allerdings noch nicht mit der geforderten Stabilität realisiert. Im Rahmen dieser Arbeit wurden verschiedene piezoelektrisch durchstimmbaren Resonatoren aufgebaut und hinsichtlich ihres Rauschverhaltens und Durchstimmbereichs untersucht. Dabei konnte gezeigt werden, dass die Resonatoren alle Anforderungen an eine durchstimmbare Vorstabilisierung für LISA erfüllen. Darüber hinaus gibt die hier präsentierte Arbeit einen neuen Einblick in das Potential von piezoelektrisch durchstimmbaren Resonatoren. Ihre Stabilität ist nur eine Größenordnung geringer als die der besten nicht durchstimmbaren Resonatoren der gleichen Länge und das gemessene Rauschen kann dabei nicht nicht den Piezoaktuatoren zugeordnet werden. Es sollte also prinzipiell möglich sein noch bessere Stabilitäten mit piezoelektrisch durchstimmbaren Resonatoren zu erzielen. In der Tat zeigen theoretische Untersuchungen, die im Rahmen dieser Arbeit durchgeführt wurden, dass die intrinsische Stabilität eines Resonators durch den Einbau eines Piezoaktuators nur geringfügig herab gesetzt wird. Hoch-stabile piezoelektrisch durchstimmbare Resonatoren können über eine Verwendung in LISA hinaus auch bei zahlreichen anderen Anwendungen zum Einsatz kommen, wie z.B. in der Cavity Enhanced Spektroskopie als Transfer Resonatoren oder als optische Lokaloszillatoren in der Atom- und Molekülspektroskopie. / The Laser Interferometer Space Antenna (LISA) is a proposed space-based gravitational wave detector that aims to detect gravitational waves in the low frequency range from 0.1 mHz to 1 Hz, which is not accessible by ground-based detectors. It consists of three satellites whose distance is monitored by laser interferometry. The high frequency stability of the lasers required for this purpose is to be achieved with a three level noise reduction scheme. This includes a pre-stabilization stage that has to feature not only high stability but also tunability. One approach for such a tunable pre-stabilization is stabilizing a laser to an optical cavity with incorporated piezoelectric actuator. While this is not a new concept per se, it has never been realized with the required stability until now. Within this thesis, different types of piezo-tunable cavities have been built and thoroughly analyzed. It could be shown that the cavities fulfill all requirements for a tunable laser pre-stabilization for LISA. Furthermore, the work presented here gives a new insight into the potential of piezo-tunable cavities. Their performance is only one order of magnitude below that of the best non-tunable cavities of the same length and the measured noise can not be attributed to the integration of the piezo actuators. So, in principal, an even better performance should be achievable with piezo-tunable cavities. Indeed, theoretical considerations performed within this thesis reveal that the intrinsic stability of piezo-tunable cavities is only slightly inferior to that of rigid cavities. Beyond an application in LISA, highly stable piezo-tunable cavities are also valuable devices for numerous other applications. They can be used in cavity enhanced spectroscopy, as transfer cavities or as optical local oscillators in atomic and molecular spectroscopy.

The aim of the study was to examine how two young female victims was represented in Swedish commercial news press, if and how their relations to the perpetrator would affect their representation and what similarities and differences there were in the representation between the two. We examined the coverage of Lisa Holm, who was murdered by a stranger, and Tova Moberg, who was murdered by her abusing ex- boyfriend. The method used was a critical discourse analysis. We searched for different discourse themes in a total of twelve news articles from Aftonbladet and Expressen. We analyzed the themes and came to the conclusion that the murder victims were represented very much alike, well-liked, ambitious and good-hearted. The main difference is that Tova Moberg was not represented as innocent as Lisa Holm by the journalism because of her relationship with her ex-boyfriend. The journalism partly blamed Tova Moberg for not preventing her own death since she was aware of the danger. We found that as soon as any kind of relations between the victim and perpetrator was mentioned the victim’s status as an ideal victim decreased.

Flüchtige organische Verbindungen (Volatile organic compounds (VOC)) sind ubiquitär vorkommende kohlenstoffhaltige Substanzen. Untersuchungen haben relevante VOC-Konzentrationen im Inneren von Gebäuden nachgewiesen. Da der Innenraum zum typischen Aufenthaltsort des modernen Menschen geworden ist, sind diese Schadstoffe in das Interesse der Forschung gerückt. Kinder reagieren unter Schadstoffexposition besonders sensibel, denn viele wichtige Organsysteme befinden sich noch in ihrer Entwicklung. In der vorliegenden Arbeit wurden Leipziger Daten der LISA-Studie („Einfluss von Lebensbedingungen und Verhaltensweisen auf die Entwicklung von Immunsystem und Allergien im Ost-West-Vergleich“) hinsichtlich möglicher Effekte einer VOC-Exposition auf Erkrankungen der Kinder im 4. Lebensjahr analysiert. Bei der LISA-Studie handelt es sich um eine multizentrische prospektive Geburts-Kohortenstudie, in die von November 1997 bis Januar 1999 insgesamt 3097 gesunde und reife Neugeborene deutscher Herkunft mit einem Geburtsgewicht > 2500 g rekrutiert wurden. Die Berechnungen der vorliegenden Arbeit erfolgten mit VOC-Messwerten um den 3. Geburtstag der Kinder. Die jeweiligen logistischen Regressionsmodelle wurden auf das Geschlecht, die atopische Familienanamnese, eine passive Tabakrauchexposition, das Aufstellen neuer Möbel im Kinderzimmer, Renovierungen und die Erneuerung des Fußbodenbelags in der Wohnung adjustiert. Es ließen sich VOC bestimmen, die bei Konzentrationserhöhungen eine erhöhte Chance für eine akute Bronchitis zur Folge hatten. Als Risikofaktor einer akuten Bronchitis ließ sich außerdem die Erneuerung des Fußbodenbelags in der Wohnung ermitteln. Während sich für eine akute Bronchitis in Abhängigkeit der VOC-Konzentration erstmals eine Dosis-Wirkungs-Kurve ableiten ließ, war dies für allergische Erkrankungen nicht möglich. Weitere Untersuchungen sind notwendig um Pathomechanismen der VOC-Einwirkungen auf den kindlichen Organismus aufzuklären.

LISA, the Laser Interferometry Space Antenna, is the 3rd large mission (L3) of the ESA program Cosmic Vision with a junior partnership from NASA planned to be launched around 2034. Space-based gravitational wave observatories such as LISA have been developed for observation of sources that produce gravitational wave (GW) signals with frequencies in the mHz regime. The frequency band is achievable by having a longer-baseline interferometer compared to ground-based detectors. In addition, the significant size of the LISA arms-length guarantees the detection of many astrophysical sources. The absence of Newtonian noise in space, which is the dominant source of noise below few hertz for ground-based detectors, allows LISA to be sensitive to lower frequency compared to the former. Thus, going to space allows studying different sources with respect to the ones of interest for ground-based detectors such as supermassive black holes. Although having very long baselines between the satellites generally increases the sensitivity to gravitational waves, it also implies many technical challenges, such that a balance must be found between scientific performance and technical feasibility.In the actual proposal LISA is designed to be a constellation of three identical spacecraft in a triangular formation with six active laser links connecting the three spacecraft, which are separated by 2.5 million km. To fulfil the observatory program every spacecraft has a minimum requirement of two free-falling test masses, two telescopes, and two lasers. The detector’s center-of-mass follows a circular, heliocentric trajectory, trailing 20 degrees behind the Earth and the plane of the detector is tilted by 60 degrees with respect to the ecliptic.The goal of LISA is to detect GWs which manifest themselves as a tiny fluctuation in the frequency of the laser beam measured at the phase-meter. Thus, to detect GW you need to compete with many sources of disturbance that simulate the effect of a GW frequency modulation. Laser noise is an example of those. Therefore, one key element in the LISA data production chain is the post-processing technique called Time Delay Interferometry aimed at suppressing the intense laser frequency noise that would completely cover the astrophysical signal. Data from the six independent inter-satellite links, connecting the three spacecraft, are properly time-shifted and combined to form the final scientific signal. This post-processing technique circumvents the impossibility of physically building in space an equal arm interferometer, which would intrinsically beat the frequency noise by comparing light generated at the same time.The following work is focused on revisiting the Time-Delay-Interferometry (TDI) for LISA and studying the usage of all the possible TDI combinations we can build for the LISA instrument characterisation and science extraction. Many possible TDI combinations that suppress the frequency noise have been identified in the past and this thesis revisits the TDI technique focusing on the physical interpretation of it, that is a virtual interference of photons that have been travelling through the constellation via different paths but performing the same total distance. We illustrate all possible TDI configurations that suppress the laser noise contribution to the level required by the mission to understand how TDI channels can be best used for the diagnostic of the instrument and LISA science. With this philosophy, we develop an algorithm to search for all possible combinations that suppress laser noise at the same level as the classical TDI X, Y, and Z combinations presented in the TDI literature. This algorithm finds new combinations that fulfill the noise suppression requirement as accurately as X, Y, and Z.The LISA mission has been also advertised to probe the early Universe by detecting a stochastic GW background. Once the laser frequency noise has been subtracted, the stochastic signal, both cosmological and astrophysical, is itself going to contribute to the noise curve. Therefore it is necessary to have a good estimate of the noise of the instrument to discriminate between the stochastic background signal and the LISA noise.The strategy that has been suggested in the literature is to use the TDI T, insensitive (up to a certain order) to GW signals to estimate the pure instrumental noise in order to distinguish between the LISA background noise and the GW stochastic signal. Following this idea, as instrument noise is expected to have multiple, independent sources, this thesis explores combinations that could allow discriminating among those sources of noise, and between them and the GW signal, with the purpose of understanding how we can characterise our instrument using TDI. We illustrate special TDI combination signals in LISA, in addition to TDI T, that we call null-channels, which are ideally insensitive to gravitational waves and only carry information about instrumental noise. Studying the noise properties that can be extracted by monitoring these interferometric signals, we state that individual acceleration noise parameters are not well constrained. All null-channels behave as an ideal Sagnac interferometer, sensitive just to a particular linear combination of the six test masses acceleration that resembles a rotational acceleration signal of the entire constellation. Moreover, all null-channels show approximately the same signal to noise ratio remarkably suppressed relative to that of the TDI X. In support and application of our theoretical studies, we also give an introduction on calibrating the LISA instrument by injecting spurious signals in a LISA link and see how these propagates through a TDI channel. Indeed, this will be useful to calibrate the instrument during operations and also to build the basis for the data analysis to discriminate spurious signals from gravitational waves. My contribution to the results we present in this thesis can be summarised as the following. I supported the studies and the realisation of the search TDI algorithm whose results are published in the article. In particular, I took care of cataloging the new TDI combinations and consolidating the results we found. I have updated the TDI combinations reported in the above-mentioned work, the final version of it is reported in this thesis. I worked on the characterisation of these combinations concerning secondary noises such as clock noise, readout noise, residual laser frequency noise, and acceleration noise. In particular, I studied how these noises are transferred through the various TDI and I derive the correspondent analytical models. I then realize a software with Wolfram Mathematica, design to load and combines phase data produced by an external simulator to build the final TDI outputs, besides I also did the noise models’ validation. The basis of this program was then used to implement these TDI combinations in LISANode. Finally, I developed the algorithm to study how disturbances in force, such as glitches, and simple GW signals, such as monochromatic GW binaries, propagate through TDI and null-channels. Moreover, I tested through simulations the validity of these TDI and null-channels to distinguish instrumental artefact from GW signals and to characterise the instrumental noise.

My work concerns the divergent narratives created by fusing varied, often conflicting, textures, colors and fabrics, into a tenuous order. I intend for these otherwise clashing materials to create drama that is simultaneously enthusiastic, epic and ambiguous. While this media's formal properties re an important component of my work, the material's cultural and art-historical associations are also are critical ingredient. In this thesis, I will explore the use of the varied collage material, hierarchical compositions and contemporary influence of 19th Century Romantic themes as they relate to forming a variety of distinctly contemporary narratives in my compositions. I will investigate how my artistic point-of-view is informed by art-history, irony and the work of contemporary painters. Finally, I will discuss how my work engages a contemporary version of the Sublime.

University of Macau / Faculty of Arts and Humanities. / Department of English

A distrofia muscular de Duchenne (DMD) é uma doença neuromuscular fatal, a mais comum das distrofias musculares, causada pela ausência da proteína distrofina, componente importante do complexo glicoproteínadistrofina, que envolve as células musculares lisas, cardíacas e esqueléticas, estabilizando a membrana dessas células durante contrações e relaxamentos. Por ser uma doença genética ligada ao cromossomo X, acomete indivíduos do sexo masculino, sendo que casos raros de meninas afetadas também são relatados. Indivíduos afetados pela DMD apresentam alterações significantes na composição corpórea, comparados com a população normal. Cães da raça golden retriever que possuem distrofia muscular (GRMD) representam o melhor modelo animal para ensaios terapêuticos na busca do tratamento da DMD, sendo esses animais fundamentais para o estudo do desenvolvimento dessa anomalia, devido ao fato de apresentarem genes e sintomas clínicos homólogos aos dos pacientes humanos. A similaridade entre as duas doenças é surpreendente, ambas são caracterizadas por precoce miopatia degenerativa, com progressiva necrose, fagocitose, deposição de cálcio e fibrose endomisial e perimisial. O foco principal deste trabalho foi esclarecer dúvidas quanto ao comportamento da musculatura lisa dos animais distróficos e portadores da GRMD, para se conhecer os efeitos da doença nesse tipo de tecido. Para avaliação da musculatura lisa uterina foram utilizados quatro úteros de cadelas golden retriever saudáveis, cinco úteros de portadoras do gene e quatro úteros de animais afetados pela GRMD. Analisando as fotomicrografias uterinas dos grupos, podemos notar que não há diferenças morfológicas através dos estudos histológicos convencionais. Porém, quando analisamos as fotomicrografias polarizadas , nota-se nas cadelas saudáveis exclusivamente colágeno do tipo III, de coloração esverdeada. Quanto às portadoras do gene da GRMD, observa-se colágeno predominantemente vermelho, do tipo I, e pouco em verde, tipo III. Fotomicrografias das fêmeas afetadas pela GRMD encontraram colágeno tipo III na parte interna do endométrio, miométrio e perimétrio, e colágeno tipo I em epitélio vascular, porém ambos em menor quantidade. É possível visualizar colágeno entre as fibras musculares através da luz polarizada. Para a avaliação da digestibilidade dos nutrientes em cães GRMD e sua capacidade absortiva, foram utilizados nove cães GRMD, sete fêmeas portadoras e dez animais saudáveis; todos receberam a mesma dieta adicionada de oxido crômico. O período experimental constou de um intervalo de 10 dias, sendo os cinco primeiros dias de adaptação e os cinco restantes de coleta de amostras. Os coeficientes de digestibilidade aparente (CDAs) obtidos pelos grupos estudados foram comparados e analisados: os resultados indicaram que os cães com GRMD avaliados não apresentaram redução do aproveitamento nutricional. Novas pesquisas que avaliem o gasto energético e composição corpórea destes animais são necessárias para melhor compreensão dos mecanismos envolvidos no emagrecimento e perda de peso que apresentam. Para a avaliação do tempo de trânsito gastrintestinal (TTGI) em cães golden retriever saudáveis, portadores e afetados pela distrofia muscular, foram utilizados 18 cães divididos em três grupos animais saudáveis, portadores e afetados pela GRMD, com seis cães cada. Os animais foram acondicionados em canis individuais e receberam a mesma dieta; esferas de polietileno (BIPS) impregnadas com bário foram fornecidas durante a alimentação. Cada animal recebeu 10 marcadores de tamanho grande (5 mm de diâmetro) e 30 marcadores de tamanho pequeno (1.5mm de diâmetro). Os animais foram radiografados nos momentos antes (basal) da 1ª refeição, para confirmação da ausência de conteúdo alimentar e fecal no trato gastrintestinal, e após a alimentação, em intervalos de duas horas, até que os marcadores atingissem o cólon. Resultados apontaram que os cães GRMD avaliados apresentam TTGI mais rápido quando comparados aos demais grupos. Este trabalho comprovou que a mm. lisa de cães distróficos é, de diversas maneiras, afetada pela doença, apresentando tanto alterações morfológicas como morfofuncionais. Muitos estudos nessa área são necessários para melhor compreensão dos mecanismos da enfermidade, bem como maneiras de intervenção para melhoria da qualidade de vida dos indivíduos afetados. Cães GRMD(s) são o melhor modelo animal para estudos pré-clínicos da DMD, assim esses resultados são muito relevantes para aprimoramento e melhora de manejo em biotérios que abrigam esses animais e para extrapolação de dados na própria medicina / Duchenne muscular dystrophy (DMD) is a fatal neuromuscular disease, it is the most common muscular dystrophy caused by absence of dystrophin protein, an important component of the dystrophin-glycoprotein complex, involving cell membranes of smooth, cardiac and skeletal cells, stabilizing these cells during contractions and relaxations. Because it is a genetic disorder linked to the X chromosome, it affects males, with rare cases of girls affected also reported. Individuals affected by DMD show significant changes in body composition, compared with the normal population. Golden retriever dogs who have muscular dystrophy (GRMD) represent the best animal model for therapeutic trials in the treatment of DMD,; these animals are fundamental to the study of the development of this anomaly, due to the fact that they show clinical symptoms and genes homologous to the human patients. The similarity between the two diseases is staggering; both are characterized by early degenerative myopathy with progressive necrosis, phagocytosis, calcium deposition and endomysial and perimysial fibrosis. The main focus of this thesis was to answer questions about the behavior of smooth muscles of dystrophic animals and carriers of GRMD, to know the effects of the disease in this tissue type. For evaluation of uterine smooth muscle we utilized four uteri of golden retriever healthy bitches, five uteri of gene carriers and four uteri of animals affected by GRMD. Analyzing the uterine photomicrographs of the groups we note that there are no morphological differences in conventional histological studies. However, when we analyze the polarized photomicrographs, we note that in healthy bitches we can see only collagen type III of greenish color. As regards the carriers of the GRMD gene, there is predominantly red collagen , type I, and very little green, type III. Photomicrographs of females affected by GRMD found type III collagen inside the endometrium, myometrium and perimetrium and collagen type I in vascular epithelium, but both in a very little quantity. It is possible to visualize collagen between muscle fibers by polarized light. For the assessment of nutrient digestibility in dogs GRMD and its absorptive capacity, we used nine GRMD, seven carriers females and ten healthy animals and all of them received the same diet with added chromic oxide. The experimental period consisted of an interval of 10 days, with the first five days to adaptation and the last ones to sample collection. The apparent digestibility coefficients obtained by the groups were compared and analyzed; the results showed that dogs with GRMD evaluated showed no reduction in energy utilization. The experimental period consisted of an interval of 10 days, with the first five days to adaptation and the last of them to sample collection. The apparent digestibility coefficients obtained by the groups were compared and analyzed; the results showed that dogs with GRMD evaluated showed no reduction in nutritional absorption. New research to assess energy expenditure and body composition in these animals are needed to a better understanding of the mechanisms involving reduction and weight loss they present. For the assessment of gastrointestinal transit time (TTGI) in golden retriever dogs healthy carriers and affected by GRMD 18 dogs divided into three groups were used - healthy animals, carriers and affected by GRMD, with six dogs each. The animals were placed in individual cages and were fed the same diet; polyethylene spheres (BIPS) impregnated with barium were supplied during feeding. Each animal received 10 markers large size (5mm diameter) and 30 markers small size (1.5mm diameter). Radiographs were taken in the moments before (baseline) the 1 st meal, to confirm the absence of food and fecal content in the gastrointestinal tract and after feeding at two-hour intervals until markers reach the colon. Results indicated that GRMD dogs evaluated showed TTGI faster when compared to the other groups. This thesis has shown that the smooth muscles of dystrophic dogs are, in many ways, affected by the disease, with both morphological and morphofunctional alterations; many studies in this area are needed so we can better understand the mechanisms of disease, as well as ways of intervention to improve the quality of life of affected individuals. GRMD dogs are the best animal model for preclinical studies of DMD, so these results are very relevant to enhancement and improvement of management in bioteries these animals have

As lajes lisas podem oferecer diversas vantagens quando comparadas ao sistema de lajes, vigas e pilares, sendo, em muitos casos, mais econômicas. O uso da protensão pode oferecer outras vantagens, tais como um melhor controle da fissuração e dos deslocamentos transversais da laje. Como a punção é um dos pontos fracos das lajes lisas protendidas, face à grande esbeltez destas lajes, apresentam-se resultados experimentais de ligações laje-pilar interno, com carregamento concêntrico, com e sem armadura de punção (conectores tipo-pino), com e sem protensão por pós-tração (cabos não aderentes). Os principais aspectos analisados foram as influências da armadura de punção e da protensão na resistência da ligação laje-pilar. Fez-se também uma análise envolvendo a previsão da resistência da ligação, dada por algumas normas e códigos. Observa-se que, de um modo aproximado, a armadura de punção eleva significativamente a resistência do modelo à punção, seja ele de concreto armado ou protendido. Observa-se ainda que, embora diminuindo a taxa de armadura dos modelos de concreto armado, para que se introduzissem as cordoalhas de protensão, os valores experimentais obtidos mostram que a presença da protensão aumentou a resistência da ligação. De um modo geral, a melhor norma que reflete o comportamento da ligação lajepilar é a Revisão da NB-1 (2000). Com relação aos modelos protendidos, o ACI poderia ter tido um bom desempenho, caso não houvesse uma restrição tão rígida com relação ao uso de armaduras de punção / The use of flat plates may offer some economical and aesthetic benefits when compared with other structural systems. The use of post-tensioned slabs may offer other advantages, as a better crack and deflection control and a thinner slab for the same span and load conditions. This work presents some experimental results and conclusions about the punching shear failure, as it is a critical problem for flat plate structures, post-tensioned or not. The main aspects analyzed are the influence of the shear reinforcement (studs) and of the post-tensioning with unbonded tendons on a slab – internal column connection strength. A comparison between experimental results and those given by some standards is presented. This comparison aims to verify if the codes accurately predict the punching shear strength of the connection. It can be noted that, in an specific comparison, the studs enhance the punching shear strength of the slab-column connection. In spite of the use of less flexural reinforcement in the post-tensioned models, the punching shear strength of the connection had a higher value when compared with the reinforced ones. This fact is due to the presence of the prestressed strands

A crotamina, um peptídeo catiônico que possui 42 aminoácidos e 4,88 kDa, é proveniente do veneno de Crotalus durissus terrificus. Ela apresenta características que permitem sua forte interação com alvos moleculares e membranas biológicas e assim foi o primeiro peptídeo de veneno a ser classificado como um CPP (cell penetrating peptide), justificando seus importantes efeitos biológicos e suas diversas atividades farmacológicas. A crotamina é descrita por sua atividade miotóxica, tendo como efeito a paralisia e espasmos das patas traseiras de ratos e camundongos. Esse fenômeno é descrito por ações em canais de Na+ e/ou K+ e consequente aumento do influxo intracelular dos níveis do íon Ca2+. Estudos a descrevem como um agente despolarizante utilizando a musculatura esquelética como modelo experimental. Outra atividade descrita da crotamina é um aumento na liberação basal de acetilcolina (ACh) e dopamina no sistema nervoso central de ratos. Até o momento, pouco ou nenhum estudo foi realizado em musculatura lisa. A junção neuromuscular autônoma difere em vários aspectos importantes da já conhecida junção neuromuscular esquelética. O ducto deferente de rato (DDR), um órgão par e tubular pertencente à genitália acessória masculina, foi utilizado como modelo experimental por ser um dos órgãos periféricos mais densamente inervados pelo sistema nervoso autônomo simpático. Esse fato, o torna uma importante ferramenta para estudos que envolvam a neurotransmissão e a ação de drogas adrenérgicas. O objetivo do presente trabalho é investigar o efeito da crotamina na contração da musculatura lisa. A crotamina foi isolada a partir do veneno de C. d. terrificus por cromatografia de exclusão molecular seguida de troca iônica. Os estudos em modelos animais foram realizados utilizando o DD (porção prostática) de ratos Wistar com 5 meses de idade entre 350 g (protocolo CEUA 1261/14). O estudo de neurotransmissão foi feito em sistema de órgão isolado (n=6) por estimulação elétrica transmural com tensão de 70V, 3ms de duração em frequências de 0,05 (30 min) e 1; 5 10 e 20Hz (30 seg). A contração isométrica foi registrada em gramas de tensão. Em todos os experimentos a crotamina (0,1;0,5 e 1g/ml) incubada 30 min antes da estimulação. O efeito máximo de contração (Emax) do componente fásico e tônico foi usado como medida. O componente pós-sináptico foi avaliado por meio de curvas dose-resposta de noradrenalina e dose única de ATP (10-3M) na presença ou ausência da crotamina. A diferença estatística foi avaliada pelo teste-t de student (P0,05). Os ensaios de estimulação elétrica de baixa frequência (0,05Hz) revelaram que a crotamina (0,1 e 0,5g/ml) promoveu uma diminuição da contração do DDR (95,7±4,6% e 85,4±5,9%, respectivamente) enquanto que na dose de 1 g/mL de crotamina este efeito não foi significativo. Na curva de freqüência observamos também com as mesmas concentrações de crotamina uma tendência à diminuição da contração fásica e tônica enquanto que a dose de 1 g/mL promoveu um aumento na contração fásica na freqüência de 20,0Hz ((3,2±0,3) em relação ao controle (2,2±0,2). O componente pós-sináptico não foi alterado pela crotamina conforme evidenciado pela curva concentração-resposta de noradrenalina e concentração única de ATP. Com base nos resultados obtidos, concluímos que a crotamina atua apenas no componente pré-sináptico da contração do DDR, provavelmente interferindo na neuroliberação de ATP e noradrenalina. Ela apresenta um efeito bifásico, dependendo da dose utilizada, inibindo ou potencializando a resposta, efeito semelhante ao da -defensinas, uma proteína cuja estrutura se assemelha bastante com a da crotamina. / Crotamin, a 4.88 kDa polypeptide composed of 42 amino acids, is derived from the venom of Crotalus durissus terrificus. It presents features that allow its strong interaction with molecular targets and biological membranes and was the first venom peptide to be classified as a CPP (cell penetrating peptide), justifying the important biological effects and different pharmacological activities of crotamine. It is described by its myotoxic activity, having the effect of paralysis and spasms of the hind legs of mice and rats. This phenomenon is described by actions on Na+ channels and / or K+ and the resulting increase in intracellular influx of Ca2+ ion levels. Studies describe crotamine as a depolarizing agent and neurotransmitter release inductor using the skeletal muscle as an experimental model. Another activity of crotamine described is an increase in the basal release of acetylcholine (ACh) and dopamine in the central nervous system of rats. To date, few or no study has been performed in smooth muscle. The autonomous neuromuscular junction differs in several important aspects of already known skeletal neuromuscular junction. The vas deferens, a pair and tubular organ belonging to the male accessory genitalia, was used as experimental model because it is one of the most densely peripheral organs innervated by the sympathetic nervous system. This fact makes it an important tool for studies involving the neurotransmission and the action of adrenergic drugs. A better understanding of crotamine mechanism of action is fundamental to the development of a pharmacological agent or a possible drug. In this context, we aim to investigate the crotamine behaviour in the contraction of the smooth muscle vas deferens through neurogenic stimulation and exogenous drugs.

Orientador: Willian Fernando Zambuzzi / Resumo: As células endoteliais (ECs) e células musculares lisas (AoSMCs) são os principais componentes celulares do endotélio. As interações entre estes tipos celulares desempenham funções na homeostase e na estrutura vascular. Como uma interface entre o sangue e a parede do vaso, as ECs ocupam um local único diretamente exposto ao shear stress (SS), a força mecânica de atrito lateral produzido pelo fluxo de sangue na membrana apical da célula endotelial, que pode influenciar o comportamento de ambas ECs e AoSMCs. Geralmente, AoSMCs não sofrem diretamente às forcas de cisalhamento, no entanto, estas são diretamente expostas ao fluxo sanguíneo quando ocorre alguma injúria vascular, como por exemplo em algumas lesões ateroscleróticas ou por técnicas invasivas, como a angioplastia. As forças hemodinâmicas influenciam as propriedades funcionais do endotélio, porém estas não são profundamente compreendidas quanto aos mecanismos bioquímicos de respostas de células endoteliais e de musculatura lisa. Assim, a proposta desta dissertação foi estabelecer um modelo de cultivo in vitro que mimetize as forças tensionais de cisalhamento (shear stress), buscando compreender mecanismos celulares, bioquímicos e epigenéticos. Cultura de células primárias endoteliais e de musculatura lisa humanas foram obtidas da empresa LONZA e mantidas conforme recomendações do fabricante. Estas células foram mantidas rotineiramente em condições convencionais em incubadora de CO2. Para mimetizar o fluxo sanguíneo, esta... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre