981 resultados para One-act plays.


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ABSTRACT - I will explore and present the portrayal of violence in some British plays that were staged between 1951 and 1965, in order to discuss the role, impact and aim of its representation. Thus, I will consider John Whiting’s Saint’s Day (1951), Ann Jelicoe’s The Sport of my Mad Mother (1956), Arnold Wesker (Chicken Soup with Barley (1958), Harold Pinter’s Birthday Party (1958), David Rudkin’s Afore Night Come (1962) and Edward Bond’s Saved (1965). My aim is to discuss the way how theatre in the post WWII changed the traditional ways of representing violence. On one hand, violence and reality became more and more familiar and domestic, permitting a representation of multiple and non-agonic violence; and, on the other hand, the violence that was depicted often changed the way one perceived reality itself, being part of a socially engaged artistic attitude.

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Uma das operações envolvidas no desmonte de maciços rochosos é a perfuração. A forma como esta é executada é determinante para o sucesso do desmonte. Quando realizada correctamente o desmonte produz uma boa fragmentação, reduzindo a sobrescavação. Assim, a correcta escolha das ferramentas de perfuração assume um papel preponderante para os custos do desmonte em maciço rochosos. Esta dissertação irá centrar-se nos parâmetros Geológicos, Geotécnicos e Geomecânicos e nos desvios de perfuração. O objectivo geral deste trabalho é perceber a interdependência dos parâmetros geológicogeotécnicos e geomecânicos do maciço rochoso com os desvios de perfuração, bem como estudar os ângulos de intersecção entre os furos e as descontinuidades que originam o desvio. O estudo dos parâmetros do maciço rochoso aliado a uma perfuração alinhada é salientado com o intuito de uma abordagem de geoengenharia integrada dos maciços rochosos.

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Trabalho de Projeto submetido à Escola Superior de Teatro e Cinema para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Teatro - especialização em Teatro e Comunidade.

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Information Society plays an important role in all kinds of human activity, inducing new forms of economic and social organization and creating knowledge. Over the last twenty years of the 20th century, large investments in telecommunication networks were made to approach economies and put an end to the asymmetries. The most isolated regions were the beneficiaries of this new technological investment’s wave disseminating trough the territories. The new economic scenarios created by globalisation make high capacity backbones and coherent information society polity, two instruments that could change regions fate and launch them in to an economic development context. Technology could bring international projection to services, products and could be the differentiating element between a national and an international economic strategy. So, the networks and its fluxes are becoming two of the most important variables to the economies. Measuring and representing this new informational accessibility, mapping new communities, finding new patterns and localisation models, could be today’s challenge. In the physical/real space, location is defined by two or three geographical co-ordinates. In the network/virtual space or in cyberspace, geography seems incapable to define location, because it doesn’t have a good model. Trying to solve the problem and based on geographical theories and concepts, new fields of study came to light. Internet Geography is one example. In this paper and using Internet Geography and informational cartography, it was possible to observe and analyse the spacialisation of the Internet phenomenon trough the distribution of the IP addresses in the Portuguese territory. This work shows the great potential and applicability of this indicator to regional development studies, and at the same time. The IP address distribution of Country Code Top Level Domains (.pt for Portugal) could show the same economic patterns, reflecting territorial inflexibility or, by opposition, new regional hierarchies. The spatial concentration or dispersion of top level domains seems to be a good instrument to analyse the info-structural dynamic and economic development of a territory, especially at regional level. At the same time it shows that information technologies are essential to innovation and competitive advantage.

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The SiC optical processor for error detection and correction is realized by using double pin/pin a-SiC:H photodetector with front and back biased optical gating elements. Data shows that the background act as selector that pick one or more states by splitting portions of the input multi optical signals across the front and back photodiodes. Boolean operations such as exclusive OR (EXOR) and three bit addition are demonstrated optically with a combination of such switching devices, showing that when one or all of the inputs are present the output will be amplified, the system will behave as an XOR gate representing the SUM. When two or three inputs are on, the system acts as AND gate indicating the present of the CARRY bit. Additional parity logic operations are performed by use of the four incoming pulsed communication channels that are transmitted and checked for errors together. As a simple example of this approach, we describe an all optical processor for error detection and correction and then, provide an experimental demonstration of this fault tolerant reversible system, in emerging nanotechnology.

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Trabalho de Projecto submetido à Escola Superior de Teatro e Cinema para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Teatro - especialização em Artes Performativas (Escritas de Cena)

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Volunteers working in different areas or different NPO (Non-profit Organisations) are significantly different according to several variables, namely in terms of motivation, satisfaction and permanence. Thus, the main goal of this research is to understand volunteers’ motivations and the influence of the context on it. Additionally, demographic variables might have an important impact on volunteers’ activities, be an important predictor of volunteering and, at the same time, influence their time commitment. In this paper we present data from twelve different NPO - 10 hospitals and 2 food banks. The model of data collection was a survey conducted by self-administered questionnaire. The results showed significant differences between the volunteers’ belonging to the two organisations and their motivations, confirming that volunteer’ motivations differ according the type/nature of organisation; this is particularly important because the field in which one works is influenced by a self-evident affinity with shared ideologies, religious convictions, and collective identities. These results present important outcomes that should be reflected in the way organisations act. Keywords: Volunteering; Occasional and permanent volunteers; Motivations; Non-profit organisations.

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The iron(III) complexes [H(EtOH)][FeCl2(L)(2)] (1), [H(2)bipy](1/2)[FeCl2(L)(2)].DMF (2) and [FeCl2(L)(2,2'-bipy)] (3) (L = 3-amino-2-pyrazinecarboxylate; H(2)bipy = doubly protonated 4,4'-bipyridine; 2,2'-bipy = 2,2'-bipyridine, DMF = dimethylformamide) have been synthesized and fully characterized by IR, elemental and single-crystal X-ray diffraction analyses, as well as by electrochemical methods. Complexes 1 and 2 have similar mononuclear structures containing different guest molecules (protonated ethanol for 1 and doubly protonated 4,4'-bipyridine for 2) in their lattices, whereas the complex 3 has one 3-amino-2-pyrazinecarboxylate and a 2,2'-bipyridine ligand. They show a high catalytic activity for the low power (10 W) solvent-free microwave assisted peroxidative oxidation of 1-phenylethanol, leading, in the presence of TEMPO, to quantitative yields of acetophenone [TOFs up to 8.1 x 10(3) h(-1), (3)] after 1 h. Moreover, the catalysts are of easy recovery and reused, at least for four consecutive cycles, maintaining 83 % of the initial activity and concomitant rather high selectivity. 3-Amino-2-pyrazinecarboxylic acid is used to synthesize three new iron(III) complexes which act as heterogeneous catalysts for the solvent-free microwave-assisted peroxidative oxidation of 1-phenylethanol.

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The yeast Saccharomyces cerevisiae is a useful model organism for studying lead (Pb) toxicity. Yeast cells of a laboratory S. cerevisiae strain (WT strain) were incubated with Pb concentrations up to 1,000 μmol/l for 3 h. Cells exposed to Pb lost proliferation capacity without damage to the cell membrane, and they accumulated intracellular superoxide anion (O2 .−) and hydrogen peroxide (H2O2). The involvement of the mitochondrial electron transport chain (ETC) in the generation of reactive oxygen species (ROS) induced by Pb was evaluated. For this purpose, an isogenic derivative ρ0 strain, lacking mitochondrial DNA, was used. The ρ0 strain, without respiratory competence, displayed a lower intracellular ROS accumulation and a higher resistance to Pb compared to the WT strain. The kinetic study of ROS generation in yeast cells exposed to Pb showed that the production of O2 .− precedes the accumulation of H2O2, which is compatible with the leakage of electrons from the mitochondrial ETC. Yeast cells exposed to Pb displayed mutations at the mitochondrial DNA level. This is most likely a consequence of oxidative stress. In conclusion, mitochondria are an important source of Pb-induced ROS and, simultaneously, one of the targets of its toxicity.

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Lead is an important environmental pollutant. The role of vacuole, in Pb detoxification, was studied using a vacuolar protein sorting mutant strain (vps16D), belonging to class C mutants. Cells disrupted in VPS16 gene, did not display a detectable vacuolar-like structure. Based on the loss of cell proliferation capacity, it was found that cells from vps16D mutant exhibited a hypersensitivity to Pb-induced toxicity, compared to wild type (WT) strain. The function of vacuolar H?-ATPase (VATPase), in Pb detoxification, was evaluated using mutants with structurally normal vacuoles but defective in subunits of catalytic (vma1D or vma2D) or membrane domain (vph1D or vma3D) of V-ATPase. All mutants tested, lacking a functional V-ATPase, displayed an increased susceptibility to Pb, comparatively to cells from WT strain. Modification of vacuolar morphology, in Pb-exposed cells, was visualized using a Vma2p-GFP strain. The treatment of yeast cells with Pb originated the fusion of the medium size vacuolar lobes into one enlarged vacuole. In conclusion, it was found that vacuole plays an important role in the detoxification of Pb in Saccharomyces cerevisiae; in addition, a functional V-ATPase was required for Pb compartmentalization.

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Abstract The emergence of multi and extensively drug resistant tuberculosis (MDRTB and XDRTB) has increased the concern of public health authorities around the world. The World Health Organization has defined MDRTB as tuberculosis (TB) caused by organisms resistant to at least isoniazid and rifampicin, the main first-line drugs used in TB therapy, whereas XDRTB refers to TB resistant not only to isoniazid and rifampicin, but also to a fluoroquinolone and to at least one of the three injectable second-line drugs, kanamycin, amikacin and capreomycin. Resistance in Mycobacterium tuberculosis is mainly due to the occurrence of spontaneous mutations and followed by selection of mutants by subsequent treatment. However, some resistant clinical isolates do not present mutations in any genes associated with resistance to a given antibiotic, which suggests that other mechanism(s) are involved in the development of drug resistance, namely the presence of efflux pump systems that extrude the drug to the exterior of the cell, preventing access to its target. Increased efflux activity can occur in response to prolonged exposure to subinhibitory concentrations of anti-TB drugs, a situation that may result from inadequate TB therapy. The inhibition of efflux activity with a non-antibiotic inhibitor may restore activity of an antibiotic subject to efflux and thus provide a way to enhance the activity of current anti-TB drugs. The work described in this thesis foccus on the study of efflux mechanisms in the development of multidrug resistance in M. tuberculosis and how phenotypic resistance, mediated by efflux pumps, correlates with genetic resistance. In order to accomplish this goal, several experimental protocols were developed using biological models such as Escherichia coli, the fast growing mycobacteria Mycobacterium smegmatis, and Mycobacterium avium, before their application to M. tuberculosis. This approach allowed the study of the mechanisms that result in the physiological adaptation of E. coli to subinhibitory concentrations of tetracycline (Chapter II), the development of a fluorometric method that allows the detection and quantification of efflux of ethidium bromide (Chapter III), the characterization of the ethidium bromide transport in M. smegmatis (Chapter IV) and the contribution of efflux activity to macrolide resistance in Mycobacterium avium complex (Chapter V). Finally, the methods developed allowed the study of the role of efflux pumps in M. tuberculosis strains induced to isoniazid resistance (Chapter VI). By this manner, in Chapter II it was possible to observe that the physiological adaptation of E. coli to tetracycline results from an interplay between events at the genetic level and protein folding that decrease permeability of the cell envelope and increase efflux pump activity. Furthermore, Chapter III describes the development of a semi-automated fluorometric method that allowed the correlation of this efflux activity with the transport kinetics of ethidium bromide (a known efflux pump substrate) in E. coli and the identification of efflux inhibitors. Concerning M. smegmatis, we have compared the wild-type M. smegmatis mc2155 with knockout mutants for LfrA and MspA for their ability to transport ethidium bromide. The results presented in Chapter IV showed that MspA, the major porin in M. smegmatis, plays an important role in the entrance of ethidium bromide and antibiotics into the cell and that efflux via the LfrA pump is involved in low-level resistance to these compounds in M. smegmatis. Chapter V describes the study of the contribution of efflux pumps to macrolide resistance in clinical M. avium complex isolates. It was demonstrated that resistance to clarithromycin was significantly reduced in the presence of efflux inhibitors such as thioridazine, chlorpromazine and verapamil. These same inhibitors decreased efflux of ethidium bromide and increased the retention of [14C]-erythromycin in these isolates. Finaly, the methods developed with the experimental models mentioned above allowed the study of the role of efflux pumps on M. tuberculosis strains induced to isoniazid resistance. This is described in Chapter VI of this Thesis, where it is demonstrated that induced resistance to isoniazid does not involve mutations in any of the genes known to be associated with isoniazid resistance, but an efflux system that is sensitive to efflux inhibitors. These inhibitors decreased the efflux of ethidium bromide and also reduced the minimum inhibitory concentration of isoniazid in these strains. Moreover, expression analysis showed overexpression of genes that code for efflux pumps in the induced strains relatively to the non-induced parental strains. In conclusion, the work described in this thesis demonstrates that efflux pumps play an important role in the development of drug resistance, namely in mycobacteria. A strategy to overcome efflux-mediated resistance may consist on the use of compounds that inhibit efflux activity, restoring the activity of antimicrobials that are efflux pump substrates, a useful approach particularly in TB where the most effective treatment regimens are becoming uneffective due to the increase of MDRTB/XDRTB.

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Para além das variáveis clínicas e sociodemográficas existem concerteza importantes componentes individuais que desempenham um contributo importante no nível de insight apresentado por cada pessoa doente, por exemplo, o nível de inteligência, personalidade, cultura, experiências passadas, memória, etc. A natureza clínica, emocional e/ou intelectual do termo ajuda-nos a compreender a complexidade da dificuldade que existe na sua tradução e, inclusive, na sua compreensão. Daí que as definições atribuídas ao conceito sejam muito distintas e variem consoante a formação teórica do autor/investigador. Pretende-se, a partir dessa identificação/compreensão, promover a qualidade de vida destas pessoas através do desenvolvimento de novas aprendizagens que possibilitem uma cooperação activa. É igualmente fundamental ir ao encontro das capacidade intactas de maneira a possibilitar a aquisição de novos(s) comportamento(s) que tenham um impacte positivo nas queixas, sinais, sintomas, incapacidade e disfuncionalidade apresentados pelo/a utente. Uma vez que a própria conceptualização do termo traduzirá aquilo que se pretende avaliar,será efectuada uma reflexão detalhada acerca dos instrumentos e definições que têm sido mais utilizadas para explorar o insight nas psicoses.Procurei, no meu trabalho de investigação, realçar e promover a importância que cada sujeito, alvo de intervenção, desempenha ao longo do seu processo de recuperação e na prevenção de recaídas. No seguimento dos objectivos acima descritos, para além da revisão teórica efectuada ao fenómeno em termos de conceptualização e estudos desenvolvidos na área de investigação, foi,neste estudo, realizada a contribuição para a validação do instrumento “Assessment of Insight in Psychosis: a re-standartization of a New Scale” de Marková & Berrios (2003).O fenómeno de insight escolhido pela Insight Scale, relata menos as mudanças vividas em relação à doença mental, e mais a actual consciência e articulação de tais mudanças. Tendo como base uma abordagem psicopedagógica, o fenómeno do insight aqui explorado assentou numa perspectiva reabilitativa, actual e multidimensional, que fosse para além das dimensões clínicas tradicionais. Neste sentido é apresentada uma escala original, intitulada “Escala de Avaliação do Insight e Identificação das Necessidades em Pessoas com Psicose”, bem como um modelo de intervenção psicopedagógico breve, assente nos pressupostos descritos ao longo do trabalho.-----------------------------------------ABSTRACT: The importance of insight in people with mental illnesses was first studied in psychiatry, in the first decades of the 20th century, by people as important as Lewis (1934) and Jaspers (1959). However, this field of investigation was left unexplored for many years. Only in the last decade has this phenomenon become the object of numerous scientific investigations, having been given special attention by its investigators. For this reason a significant number of instruments for evalauting insight in psychotic disorders were developed. Since then many papers have been published, which has allowed for a more in depth knowledge on the subject. Therefore, in recent years, the concept of insight has been developed in an attempt to clarify its compexity. A once dichotomic phenomenon, described in terms of presence or absence, became considered multidimensional, which made the identification of different levels of insight and different dimensions possible. Current concepts categorize insight into five dimensions: the awareness of the patient in relation to his/her mental illness, the awareness of the patient in relation to the social consequences of his/her illness, the awareness of the need for treatment, the awareness of the symptoms and the explanation of those symptoms in relation to the illness. The lack of insight in psychiatry, in general terms, and as this phenomenon has been described, the lack of awareness of having a mental illness, represents one of the most common symptoms of schizophrenia and affects a big part of the population that suffer from this illness. It is estimated that bewteen 50 and 80 per cent of patients with schizophrenia do not believe that they are ill, which, consequently has a big impact in the process of adherence to treatment. It is still not possible, however, to identify all the factors that determine the lack of insight in schizophrenics. There are psychological, social and cultural influences that almost certainly play their role in the lack of insight registered in this pathology.Since the impact of scizophrenia is felt in many aspects of the individual’s life, its effective treatment should be directed at various levels, including the improvement of insight. One of the objectives of this study is to explore the relationship between the level of insight in psychosis and the clinical and sociodemographic variables, the psychopathology and its global functioning. As well as the clinical and sociodemographic variables, there are of course important individual components that contribute to the level of insight seen in each patient, for example, their level of inteligence, personality, culture, past experiences, memory, etc. The clinical, emotional and/or intelectual nature of the term helps us understand the difficulty that lies in its interpretation as well as in its comprehension. Therefore, the definitions attributed to the term are very different and vary according to the theoretical training of the investigator. It is intended, from this identification/understanding, to promote the quality of life of these people through the development of new findings that might enable an active cooperation. It is equally fundamental to observe their unimpaired capacities in order to enable the acquisition of new behaviour(s) that have a positive impact on the complaints, signs, symptoms, incapacity and disfunctioning seen in the patient.As the actual comprehension of the term explains what we intend to evaluate, a detailed reflection is made on the instruments and definitions that have been used the most to explore insight in psychosis.In this investigation I tried to underline and promote the importance that each subject, undergoing medical intervention, plays during his/her process of recovery and prevention of relapses. Considering the above mentioned objectives, as well as a theoretical review of the phenomenon in terms of conceptualization and investigative studies developed, this study contributed to the validation of the instrument.The insight phenomenon chosen by the “Insight Scale”, records less changes experienced in relation to the mental illness and more actual awareness and articulation of these changes. Based on a psychopedagogical approach, the insight phenomenon explored here settled on a rehabilitation, current and multidimensional perspective that would go beyond the traditional clinical dimensions. For this reason an original scale entitled “Insight Evaluation Scale and Need Identification in Psychosis Patients” is presented, as well as a psychopedagogical intervention model soon to be used with admitted patients based on the presuppositions described in this study.

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The game of football demands new computational approaches to measure individual and collective performance. Understanding the phenomena involved in the game may foster the identification of strengths and weaknesses, not only of each player, but also of the whole team. The development of assertive quantitative methodologies constitutes a key element in sports training. In football, the predictability and stability inherent in the motion of a given player may be seen as one of the most important concepts to fully characterise the variability of the whole team. This paper characterises the predictability and stability levels of players during an official football match. A Fractional Calculus (FC) approach to define a player’s trajectory. By applying FC, one can benefit from newly considered modeling perspectives, such as the fractional coefficient, to estimate a player’s predictability and stability. This paper also formulates the concept of attraction domain, related to the tactical region of each player, inspired by stability theory principles. To compare the variability inherent in the player’s process variables (e.g., distance covered) and to assess his predictability and stability, entropy measures are considered. Experimental results suggest that the most predictable player is the goalkeeper while, conversely, the most unpredictable players are the midfielders. We also conclude that, despite his predictability, the goalkeeper is the most unstable player, while lateral defenders are the most stable during the match.

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Resumo: a febre botonosa, também conhecida por febre escaro-nodular (FEN) é uma doença endémica nos Países da bacia do Mediterrâneo, África, Médio Oriente, Índia e Paquistão. O agente etiológico responsável por esta patologia é a bactéria Rickettsia conorii. Contudo, em alguns países, como Portugal e Itália, esta patologia é causada por duas estirpes diferentes: R conorii Malish e R conorii Israeli spotted fever strain. O principal vector e reservatório é o ixodídeo Rhipicephalus sanguineus. Mesmo com uma elevada taxa de subnotificação detectada no nosso País, a taxa incidência da FEN é de 8.4/105 habitantes (1989-2005), uma das mais altas quando comparada coom a de outros países da bacia do Mediterrâneo. De todos os distritos portugueses, Bragança e Beja são aqueles que apresentam as taxas de incidência mais elevadas, 56,8/105 habitantes e 47,4 / 105 habitantes respectivamente. Em Portugal, as alterações climáticas verificadas na última década, nomeadamente a subida das temperaturas médias anuais, parecem ter influenciado o ciclo de vida do vector e a sua dinâmica sazonal, permitindo ao R. sanguineus completar mais de um ciclo de vida por ano. Este facto, e a possibilidade deste vector se manter activo noutros meses do ano, nomeadamente nos meses de inverno, tem influenciado consequentemente o padrão de distribuição anual dos casos de FEN. A febre escaro-nodular caracteriza-se clinicamente como uma doença exantemática, com um processo de vasculite generalizado. Apesar de na generalidade ser considerada uma doença benigna (quando tratada atempadamente e com terapêutica adequada e específica)e de estarem descritos casos graves em cerca de 5-6% dos doentes, em Portugal essa percentagem aumentou e consequentemente levou a um aumento de casos fatais. Este facto tornou-se mais evidente em 1997, no Hospital Distrital de Beja e no Hospital Garcia de Orta, onde a taxa de letalidade atingiu os 32% e 18% respectivamente.Para além dos factores de co-morbilidade encontrados nos doentes mais graves, como diabetes mellitus, ou o atraso na instituição da terapêutica específica, foi colocada de que a estirpe R. conorii Israel spotted fever strain pudesse ser mais virulenta ou então estivesse associada a diferentes manifestações clínicas que dificultassem o diagnóstico clínico e a instituição atempada da terapêutica. Houve ainda a necessidade de avaliar alguns parâmetros imunológicos dos doentes e tentar identificar que factores, nomeadamente que citoquinas, poderiam estar envolvidos na resposta a uma infecção por R.conorii.Face a estas questões foi avaliada e comparada a epidemiologia, manifestações clínicas e laboratoriais de 140 doentes (71 infectados com R. conorii Malish e 69 infectados com R. conorii Israel spotted fever strain). Concluiu-se que existe uma sobreposição de manifestações clinicas entre os dois grupos de doentes, mas que a percentagem da escara de inoculação é significativamente inferior em doentes infectados com R. conorii Israel spotted fever strain. Dos resultados mais importantes encontrados neste estudo concluiu-se que a estirpe R. conorii Malish e é demonstrado, pela primeira vez, estatisticamente que o alcoolismo é um factor de risco para a morte de doentes com FEN. Associadas a factores de um mau prognósitco da doença, estão as manifestações gastrointestinais, que poderão ser ou não reflexo de alterações do sistema nervoso central, e ainda a alteração de parâmetros laboratoriais como a presença de hiperbilirubinemia e aumento dos valores da ureia.A maior parte dos estudos realizados sobre os mecanismos da resposta imunitária à infecção por R. conorii e as interacções hospedeiro - agente etiológico têm sido elucidados com base em modelos animais. Poucos estudos têm sido efectuados em doentes e nenhum estudo prévio tinha sido realizado no sentido de avaliar localmente (escara/pele) quais os mediadores ou outras moléculas envolvidas na resposta imunitária às rickettsioses. Foi avaliado o nível de expressão génica de RNA mensageiro (RNAm)de diferentes citoquinas em amostras de pele de doentes com FEN pela técnica de PCR em tempo real.Os resultados deste estudo mostraram que, quando comparado com o grupo controlo, os 23 doentes analisados apresentavam níveis estatisticamente significativos, mais elevados de expressão génica de interferão (IFN-γ, Tumor necrosis factor (TFN-α, interleucina 10 (IL-10, RANTES (regulated by activation, normal T-cell-expressed and secreted chemokine)e indolamina 2-3 desoxigenase (IDO),uma enzima envolvida no controlo e limitação do crescimento intracelular das rickettsias, através da degradação do triptofano. Seis dos 23 doentes apresentaram ainda niveis de expressão elevados de óxido nítrico indutível (iNOS)que actua como microbicida. Encontrou-se uma correlação positiva entre a expressão de RNAm de TNF-α, γ, iNOS e IDO e os casos menos graves de FEN sugerindo um tipo de resposta imunitária tipo Th1, i.e. com papel protector na resposta à infecção.Verificou-se também que os valores de expressão genética do RNAm de IL-10, estavam inversamente correlacionados com a expressão do RNAm de TNF-α e IFN-γ. Os casos menos graves de FEN parecem assim envolver um balanço entre a resposta pró-inflamatória e anti-inflamatória. Já os níveis de expressão génica do RNAm de IL-10 estavam inversamente correlacionados com a expressão RNAm de TNF-α e IFN-γ. Os casos menos graves de FEN parecem assim envolver um balanço entre uma resposta pró-inflamatória e anti-inflamatória. Já os níveis de expressão RNAm da quimoquina RANTES foram estatisticamente mais elevados em doentes graves.Nesta dissertação é ainda descrita uma nova rickettsiose presente em Portugal, causada pela bactéria R. sibirica mongolitimonae, que foi identificada laboratorialmente por isolamento do agente, e por detecção do DNA em biopsia de pele. A presença deste agente foi ainda corroborada pela detecção em paralelo do mesmo agente no ixodídeos como R. africae like e em pulgas como R. felis e R.typhi alertam para a possibilidade de existência de outras rickettsioses que possam estar diagnosticadas em Portugal. Abstract: Mediterranean spotted fever (MSF), a tick-borne disease caused by Rickettsia conorii, is widley distributed in the Old World, being endemic in the southern Europe, Africa, Middle East, India and Pakistan. In Portugal two strains cause disease: R.conorii Malish and R.conorii Israeli spotted fever.Rhipicephalus sanguineus, the brown dog tick, is considered the main vector and reservoir. MSF is characterized by seasonality, and most of cases are encountered in late spring and summer, peaking in July and August. However, CEVDI/INSA laboratory has observed that the incidence of MSF cases has changed during winter season.The increasing annual averages of air temperatures and warmer and drier winters might have influenced the dynamics of the life cycle and activity of R. sanguineus, and indirectley the number MSF cases during the so called MSF off-season.In the period of 1989-2005, the incidence rate of MSF was 8.4/105 inhabitants, one of the highest rates compared with other endemic countries. In the Portugal during the same period, the highest incidence rates were reported in the districts of Bragança, with 56.8/105 inhabitants, and Beja, with 47.4/105 inhabitants. Severe cases of MSF are reported in 6% of the patients, but it seems that this pattern of disease in Portugal has been changing.This factor became more evident in 1997, with a reported case fatality rate of 32% and 18% in patients with MSF admited at Beja and Garcia Orta Hospitals, respectively. Although it was found that diabetes mellitus and delay in therapy have been implicated as a risk factor for death, the hypothesis was considered, that the new ISF strain isolated from Portugueses patients in the same year (1997)causes different or atypical clinical conorii Malish strain. The local (skin biopsies) immune response to R. conorii infection was also evaluated.A prospective study was performed to characterized epidemiological, clinical, laboratory features and determined risk factors for a fatal outcome. One hundred forty patients (51% patients were infected with Rickettsia conorii Malish stain and 49% with Israeli spotted fever strain)with diagnosis documented with identification of the causative rickettsial strain were admitted to 13 Portugueses Hospitals during 1994-2006.Comparison of the clinical manifestations of MSF caused by Malish and ISF strains revealed tremendous overlap that would not permit clinical recognition of the strain envolved, but an eschar was observed in a significantly higher percentage of patients with Malish than ISF strain.A fatal outcome was significantly more likely for patients with ISF strain infection meaning that ISF strain was more virulent than Malish strain, and also alcoholism was a host risk factor for a fatal outcome.The pathophysiology of a fatal outcome involved significantly greater incidence of petechial rash, gastrointestinal symptoms, confusion/obtundation, dehydration, tachypnea, hepatomegaly, leukocytosis, coagulopathy, azotemia, hyperbilirubinemia, and elevated hepatic enzymes and creatine kinase. Multivariate analysis revealed that acute renal failure and hyperbilirubinemia were most strong associated with a fatal oucome of infections with both strains.The immune response to R. conorii infection determined with both strains. The immune response to R. conorii infection determined by the expression levels of inflammatory and immune mediators in skin biopsies collected from untreated patients with Mediterranean spotted fever reveal that intralesional expression of mRNA of TNF-α, IFN-γ, IL-10, RANTES, and indoleamine-2, 3-dioxygenase (IDO)an enzyme involved in limiting rickettsial growth by tryptophan degradation, were elevated in skin of MSF patients compared to controls. Six patients had elevated levels of inducible nitric oxide synthase (NOS2, a source microbicidal nitric oxide.Positive correlations among TNF-α, IFN-γ, NOS2,IDO and mild-to-moderate disease suggested that type 1 polarization plays a protective role. Significantly high levels of intralesional IL-10 were inversely correlated with IFN-γ and TNF-α. The chemokine RANTES was significantly higher in patients with several MSF. It seems that MSF patients with mild-to-moderate disease have a strong and balanced intralesional pro-inflammatory and anti-inflammatory response, while severe disease is associated with higher chemokine expression.Whether these findings are simply a correlate of mild and severe disease or contribute to anti-rickettsial immunity and pathogenesis remains to be determined.In this dissertation is also described a new rickettsiois present in Portugal caused by R.sibirica mongolitimonae strain, identified based on agent isolation and DNA detection by PCR technique in a skin biopsy.The presence of this agent corroborated by its detection also in Rhipicephalus pusillus tick. Also, pathogenic tick and flea-borne rickettsial agents such as R. africae strain detected in Rhipicephalus bursa tick, and R.felis and R.typhi detected in different fleas species raise the alert for the possible existence of other rickettsioses in Portugal that might be underdiagnosed.

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Nearly 400 hemodialysis patients treated at 5 different hemodialysis units in Rio de Janeiro were tested for one year for the presence of hepatitis C and B markers. During the same period, samples were also obtained from 35 continuous ambulatory peritoneal dialysis (CAPD) patients and from 242 health care workers. Depending on the hemodialysis unit studied, anti-HCV prevalence rates ranging from 47% to 82% (mean 65%) were detected. CAPD patients showed a lower prevalence of 17%. The prevalence of antibodies against hepatitis C virus (anti-HCV) among health care workers was 2.9%. We observed a hepatitis C attack rate of 11.5% per year in the anti-HCV-negative hemodialysis patient population. An average of 9.4% of the hemodialysis patients were chronic carriers of hepatitis B virus (HBV) (range 1.8% - 20.4%), while 48.9% showed markers of previous HBV infection. The HBV attack rate was 4.5% per year (range 0% - 6%). These results indicate an alarming high prevalence of anti-HCV among hemodialysis patients of this studied region.