745 resultados para Digestive Disorders


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Chapter 1 introduces the scope of the work by identifying the clinically relevant prenatal disorders and presently available diagnostic methods. The methodology followed in this work is presented, along with a brief account of the principles of the analytical and statistical tools employed. A thorough description of the state of the art of metabolomics in prenatal research concludes the chapter, highlighting the merit of this novel strategy to identify robust disease biomarkers. The scarce use of maternal and newborn urine in previous reports enlightens the relevance of this work. Chapter 2 presents a description of all the experimental details involved in the work performed, comprising sampling, sample collection and preparation issues, data acquisition protocols and data analysis procedures. The proton Nuclear Magnetic Resonance (NMR) characterization of maternal urine composition in healthy pregnancies is presented in Chapter 3. The urinary metabolic profile characteristic of each pregnancy trimester was defined and a 21-metabolite signature found descriptive of the metabolic adaptations occurring throughout pregnancy. 8 metabolites were found, for the first time to our knowledge, to vary in connection to pregnancy, while known metabolic effects were confirmed. This chapter includes a study of the effects of non-fasting (used in this work) as a possible confounder. Chapter 4 describes the metabolomic study of 2nd trimester maternal urine for the diagnosis of fetal disorders and prediction of later-developing complications. This was achieved by applying a novel variable selection method developed in the context of this work. It was found that fetal malformations (FM) (and, specifically those of the central nervous system, CNS) and chromosomal disorders (CD) (and, specifically, trisomy 21, T21) are accompanied by changes in energy, amino acids, lipids and nucleotides metabolic pathways, with CD causing a further deregulation in sugars metabolism, urea cycle and/or creatinine biosynthesis. Multivariate analysis models´ validation revealed classification rates (CR) of 84% for FM (87%, CNS) and 85% for CD (94%, T21). For later-diagnosed preterm delivery (PTD), preeclampsia (PE) and intrauterine growth restriction (IUGR), it is found that urinary NMR profiles have early predictive value, with CRs ranging from 84% for PTD (11-20 gestational weeks, g.w., prior to diagnosis), 94% for PE (18-24 g.w. pre-diagnosis) and 94% for IUGR (2-22 g.w. pre-diagnosis). This chapter includes results obtained for an ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) study of pre-PTD samples and correlation with NMR data. One possible marker was detected, although its identification was not possible. Chapter 5 relates to the NMR metabolomic study of gestational diabetes mellitus (GDM), establishing a potentially predictive urinary metabolic profile for GDM, 2-21 g.w. prior to diagnosis (CR 83%). Furthermore, the NMR spectrum was shown to carry information on individual phenotypes, able to predict future insulin treatment requirement (CR 94%). Chapter 6 describes results that demonstrate the impact of delivery mode (CR 88%) and gender (CR 76%) on newborn urinary profile. It was also found that newborn prematurity, respiratory depression, large for gestational age growth and malformations induce relevant metabolic perturbations (CR 82-92%), as well as maternal conditions, namely GDM (CR 82%) and maternal psychiatric disorders (CR 91%). Finally, the main conclusions of this thesis are presented in Chapter 7, highlighting the value of maternal or newborn urine metabolomics for pregnancy monitoring and disease prediction, towards the development of new early and non-invasive diagnostic methods.

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Mitochondria are central organelles for cell survival with particular relevance in energy production and signalling, being mitochondrial fatty acid β–oxidation (FAO) one of the metabolic pathways harboured in this organelle. FAO disorders (FAOD) are among the most well studied inborn errors of metabolism, mainly due to their impact in health. Nevertheless, some questions remain unsolved, as their prevalence in certain European regions and how pathophysiological determinants combine towards the phenotype. Analysis of data from newborn screening programs from Portugal and Spain allowed the estimation of the birth prevalence of FAOD revealing that this group of disorders presents in Iberia (and particularly in Portugal) one of the highest European birth prevalence, mainly due to the high birth prevalence of medium chain acyl-CoA dehydrogenase deficiency. These results highlight the impact of this group of genetic disorders in this European region. The characterization of mitochondrial proteome, from patients fibroblasts with FAOD, namely multiple acyl-CoA dehydrogenase deficiency (MADD) and long chain acyl-CoA dehydrogenase deficiency (LCHADD), provided a global perspective of the mitochondrial proteome plasticity in these disorders and highlights the main molecular pathways involved in their pathogenesis. Severe MADD forms show an overexpression of chaperones, antioxidant enzymes (MnSOD), and apoptotic proteins. An overexpression of glycolytic enzymes, which reflects cellular adaptation to energy deficiency due to FAO blockage, was also observed. When LCHADD fibroblasts were analysed a metabolic switching to glycolysis was also observed with overexpression of apoptotic proteins and modulation of the antioxidant defence system. Severe LCHADD present increased ROS alongside with up regulation of MnSOD while moderate forms have lower ROS and down-regulation of MnSOD. This probably reflects the role of MnSOD in buffering cellular ROS, maintain them at levels that allow cells to avoid damage and start a cellular response towards survival. When ROS levels are very high cells have to overexpress MnSOD for detoxifying proposes. When severe forms of MADD were compared to moderate forms no major differences were noticed, most probably because ROS levels in moderate MADD are high enough to trigger a response similar to that observed in severe forms. Our data highlights, for the first time, the differences in the modulation of antioxidant defence among FAOD spectrum. Overall, the data reveals the main pathways modulated in FAOD and the importance of ROS levels and antioxidant defence system modulation for disease severity. These results highlight the complex interaction between phenotypic determinants in FAOD that include genetic, epigenetic and environmental factors. The development of future better treatment approaches is dependent on the knowledge on how all these determinants interact towards phenotype.!

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In a previous exploratory study we observed no relevant differences in psychopathology, personality, and functioning between inpatients diagnosed with gastrointestinal motor disorders (GMDs) or functional gastrointestinal disorders (FGDs) [1]. However, we observed higher levels of incongruence between clinician-assessed performance status and patients’ self-reported levels of functioning among patients diagnosed with FGDs. Likewise, research in other medical conditions has shown incongruences between self-reported and clinician-reported or objective measures [2]. Furthermore, in a study on chronic depression, the authors found that discrepancies between patients’ and physicians’ assessments of medical comorbidities were related to higher levels of depressive symptomatology [3]. In this line, the aim of this study was to explore whether the inconsistencies between clinician-assessed and patient self-reported levels of functioning could be related to psychopathology among patients admitted for evaluation of gastrointestinal motility.

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Recent research has started to identify mood disorders and problems associated with acute and chronic wounds, which have been shown to contribute to delayed healing, poor patient well-being and a reduced quality of life. Furthermore, mood disorders have been shown to have a negative impact on financial costs for service providers and the wider society in terms of treatment and sickness absence. This study aimed to survey a multinational sample of health professionals to explore their perspective and awareness of mood disorders amongst acute and chronic wound patients. Responses were received from n = 908 health professionals working in Asia, Africa, Australia, Europe, North America and South America. A strong awareness of the prevalence of mood disorders appeared to be widespread among the health professionals across the world, in addition to a view on the potential factors contributing to these problems with mood. Despite this, it was thought that few patients were actually receiving treatment for their mood disorders. Implications for clinical practice include the need for health professionals to actively engage with their patients to enable them to learn from their experiences. Studies that explore the benefits of treatments and techniques appropriate for minimising mood disorders in patients with wounds would provide empirical evidence for health professionals to make recommendations for patients with acute and chronic wounds.

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Background. Patients with anxiety disorder diagnoses commonly have more than one anxiety diagnosis. While cognitive-behavioral interventions have proven efficacy in treating single anxiety disorder diagnoses, there has been little investigation of their efficacy in treating cooccurring anxiety disorders. Aims. To evaluate the efficacy of a transdiagnostic cognitive-behavioral intervention for treating co-occurring anxiety disorders. Methods. An A-B single case study design (N = 6) was used to evaluate the efficacy of a 12 to 13 session modular transdiagnostic cognitive-behavioral intervention for treating co-occurring anxiety disorders across patients with at least two of the following diagnoses: GAD, Social Phobia, Panic Disorder and/or OCD. Results. Five of the six participants completed treatment. At post-treatment assessment the five treatment completers achieved diagnostic and symptomatic change with three participants being diagnosis free. All participants who completed treatment no longer met criteria for any DSM-IV-TR Axis-I diagnosis at the three-month follow-up assessment, and demonstrated reliable and clinically-significant improvements in symptoms. Across the participants, statistically significant improvements from pre- to post-intervention were found on measures of anxiety, depression and general well-being, and all improvements were maintained at three-month follow-up. Conclusions. Results suggest that transdiagnostic cognitive behavioral interventions can be of benefit to patients with co-occurring anxiety disorders.

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BACKGROUND: Affective instability (AI), childhood trauma, and mental illness are linked, but evidence in affective disorders is limited, despite both AI and childhood trauma being associated with poorer outcomes. Aims were to compare AI levels in bipolar disorder I (BPI) and II (BPII), and major depressive disorder recurrent (MDDR), and to examine the association of AI and childhood trauma within each diagnostic group. METHODS: AI, measured using the Affective Lability Scale (ALS), was compared between people with DSM-IV BPI (n=923), BPII (n=363) and MDDR (n=207) accounting for confounders and current mood. Regression modelling was used to examine the association between AI and childhood traumas in each diagnostic group. RESULTS: ALS scores in descending order were BPII, BPI, MDDR, and differences between groups were significant (p<0.05). Within the BPI group any childhood abuse (p=0.021), childhood physical abuse (p=0.003) and the death of a close friend in childhood (p=0.002) were significantly associated with higher ALS score but no association was found between childhood trauma and AI in BPII and MDDR. LIMITATIONS: The ALS is a self-report scale and is subject to retrospective recall bias. CONCLUSIONS: AI is an important dimension in bipolar disorder independent of current mood state. There is a strong link between childhood traumatic events and AI levels in BPI and this may be one way in which exposure and disorder are linked. Clinical interventions targeting AI in people who have suffered significant childhood trauma could potentially change the clinical course of bipolar disorder.

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Tese de doutoramento, Medicina Dentária (Dentisteria Conservadora), Universidade de Lisboa, Faculdade de Medicina Dentária, 2016

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Among organic pollutants existing in coastal areas, polycyclic aromatic hydrocarbons (PAHs) are of great concern due to their ubiquity and carcinogenic potential. The aim of this study was to evaluate the seasonal patterns of PAHs in the digestive gland and arm of the common octopus (Octopus vulgaris) from the Northwest Atlantic Portuguese coast. In the different seasons, 18 PAHs were determined and the detoxification capacity of the species was evaluated. Ethoxyresorufin O-deethylase (EROD) and ethoxycoumarin O-deethylase (ECOD) activities were measured to assess phase I biotransformation capacity. Individual PAH ratios were used for major source (pyrolytic/petrogenic) analysis. Risks for human consumption were determined by the total toxicity equivalence approach. Generally, low levels of PAHs were detected in the digestive gland and in the arm of octopus, with a predominance of low molecular over high molecular weight compounds. PAHs exhibited seasonality in the concentrations detected and in their main emission sources. In the digestive gland, the highest total PAH levels were observed in autumn possibly related to fat availability in the ecosystem and food intake. The lack of PAH elimination observed in the digestive gland after captivity could be possibly associated to a low biotransformation capacity, consistent with the negligible/undetected levels of EROD and ECOD activity in the different seasons. The emission sources of PAHs found in the digestive gland varied from a petrogenic profile observed in winter to a pyrolytic pattern in spring. In the arm, the highest PAH contents were observed in June; nevertheless, levels were always below the regulatory limits established for food consumption. The carcinogenic potential calculated for all the sampling periods in the arm were markedly lower than the ones found in various aquatic species from different marine environments. The results presented in this study give relevant baseline data for environmental monitoring of organic pollution in coastal areas.

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Soft-tissue and bone necrosis, although rare in childhood, occasionally occur in the course of infectious diseases, either viral or bacterial, and seem to be the result of hypoperfusion on a background of disseminated intravascular coagulation. Treatment consists in correction of septic shock and control of necrosis. Necrosis, once started, shows extraordinarily rapid evolution, leading to soft-tissue and bone destruction and resulting in anatomic, functional, psychological, and social handicaps. Ten mutilated children were treated from January 1986 to January 1999 in Hospital de Dona Estefaˆ nia, Lisbon, Portugal. One was recovering from hemolytic-uremic syndrome with a severe combined immunodeficiency, another malnourished, anemic child had malaria, and three had chicken pox (in one case complicated by meningococcal septicemia). There were three cases of meningococcal and two of pyocyanic septicemia (one in a burned child and one in a patient with infectious mononucleosis). The lower limbs (knee,leg, foot) were involved in five cases, the face (ear, nose, lip) in four, the perineum in three, the pelvis (inguinal region, iliac crest) in two, the axilla in one, and the upper limb (radius, hand) in two. Primary prevention is based on early recognition of risk factors and timely correction. Secondary prevention consists of immediate etiologic and thrombolytic treatment to restrict the area of necrosis. Tertiary prevention relies on adequate rehabilitation with physiotherapy and secondary operations to obtain the best possible functional and esthetic result.

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RESUMO: A reprogramação celular permite que uma célula somática seja reprogramada para outra célula diferente através da expressão forçada de factores de transcrição (FTs) específicos de determinada linhagem celular, e constitui uma área de investigação emergente nos últimos anos. As células somáticas podem ser experimentalmente manipuladas de modo a obter células estaminais pluripotentes induzidas (CEPi), ou convertidas directamente noutro tipo de célula somática. Estas descobertas inovadoras oferecem oportunidades promissoras para o desenvolvimento de novas terapias de substituição celular e modelos de doença, funcionando também como ferramentas valiosas para o estudo dos mecanismos moleculares que estabelecem a identidade celular e regulam os processos de desenvolvimento. Existem várias doenças degenerativas hereditárias e adquiridas da retina que causam deficiência visual devido a uma disfunção no tecido de suporte da retina, o epitélio pigmentar da retina (EPR). Uma destas doenças é a Coroideremia (CHM), uma doença hereditária monogénica ligada ao cromossoma X causada por mutações que implicam a perda de função duma proteína com funções importantes na regulação do tráfico intracelular. A CHM é caracterizada pela degenerescência progressiva do EPR, assim como dos foto-receptores e da coróide. Resultados experimentais sugerem que o EPR desempenha um papel importante na patogénese da CHM, o que parece indicar uma possível vantagem terapêutica na substituição do EPR nos doentes com CHM. Por outro lado, existe uma lacuna em termos de modelos in vitro de EPR para estudar a CHM, o que pode explicar o ainda desconhecimento dos mecanismos moleculares que explicam a patogénese desta doença. Assim, este trabalho focou-se principalmente na exploração das potencialidades das técnicas de reprogramação celular no contexto das doenças de degenerescência da retina, em particular no caso da CHM. Células de murganho de estirpe selvagem, bem como células derivadas de um ratinho modelo de knockout condicional de Chm, foram convertidos com sucesso em CEPi recorrendo a um sistema lentiviral induzido que permite a expressão forçada dos 4 factores clássicos de reprogramação, a saber Oct4, Sox2, Klf4 e c-Myc. Estas células mostraram ter equivalência morfológica, molecular e funcional a células estaminais embrionárias (CES). As CEPi obtidas foram seguidamente submetidas a protocolos de diferenciação com o objectivo final de obter células do EPR. Os resultados promissores obtidos revelam a possibilidade de gerar um valioso modelo de EPR-CHM para estudos in vitro. Em alternativa, a conversão directa de linhagens partindo de fibroblastos para obter células do EPR foi também abordada. Uma vasta gama de ferramentas moleculares foi gerada de modo a implementar uma estratégia mediada por FTs-chave, seleccionados devido ao seu papel fundamental no desenvolvimento embrionário e especificação do EPR. Conjuntos de 10 ou menos FTs foram usados para transduzir fibroblastos, que adquiriram morfologia pigmentada e expressão de alguns marcadores específicos do EPR. Adicionalmente, observou-se a activação de regiões promotoras de genes específicos de EPR, indicando que a identidade transcricional das células foi alterada no sentido pretendido. Em conclusão, avanços significativos foram atingidos no sentido da implementação de tecnologias de reprogramação celular já estabelecidas, bem como na concepção de novas estratégias inovadoras. Metodologias de reprogramação, quer para pluripotência, quer via conversão directa, foram aplicadas com o objectivo final de gerar células do EPR. O trabalho aqui descrito abre novos caminhos para o estabelecimento de terapias de substituição celular e, de uma maneira mais directa, levanta a possibilidade de modelar doenças degenerativas da retina com disfunção do EPR numa placa de petri, em particular no caso da CHM.---------------ABSTRACT: Cellular reprogramming is an emerging research field in which a somatic cell is reprogrammed into a different cell type by forcing the expression of lineage-specific transcription factors (TFs). Cellular identities can be manipulated using experimental techniques with the attainment of pluripotency properties and the generation of induced Pluripotent Stem (iPS) cells, or the direct conversion of one somatic cell into another somatic cell type. These pioneering discoveries offer new unprecedented opportunities for the establishment of novel cell-based therapies and disease models, as well as serving as valuable tools for the study of molecular mechanisms governing cell fate establishment and developmental processes. Several retinal degenerative disorders, inherited and acquired, lead to visual impairment due to an underlying dysfunction of the support cells of the retina, the retinal pigment epithelium (RPE). Choroideremia (CHM), an X-linked monogenic disease caused by a loss of function mutation in a key regulator of intracellular trafficking, is characterized by a progressive degeneration of the RPE and other components of the retina, such as the photoreceptors and the choroid. Evidence suggest that RPE plays an important role in CHM pathogenesis, thus implying that regenerative approaches aiming at rescuing RPE function may be of great benefit for CHM patients. Additionally, lack of appropriate in vitro models has contributed to the still poorly-characterized molecular events in the base of CHM degenerative process. Therefore, the main focus of this work was to explore the potential applications of cellular reprogramming technology in the context of RPE-related retinal degenerations. The generation of mouse iPS cells was established and optimized using an inducible lentiviral system to force the expression of the classic set of TFs, namely Oct4, Sox2, Klf4 and c-Myc. Wild-type cells, as well as cells derived from a conditional knockout (KO) mouse model of Chm, were successfully converted into a pluripotent state, that displayed morphology, molecular and functional equivalence to Embryonic Stem (ES) cells. Generated iPS cells were then subjected to differentiation protocols towards the attainment of a RPE cell fate, with promising results highlighting the possibility of generating a valuable Chm-RPE in vitro model. In alternative, direct lineage conversion of fibroblasts into RPE-like cells was also tackled. A TF-mediated approach was implemented after the generation of a panoply of molecular tools needed for such studies. After transduction with pools of 10 or less TFs, selected for their key role on RPE developmental process and specification, fibroblasts acquired a pigmented morphology and expression of some RPE-specific markers. Additionally, promoter regions of RPE-specific genes were activated indicating that the transcriptional identity of the cells was being altered into the pursued cell fate. In conclusion, highly significant progress was made towards the implementation of already established cellular reprogramming technologies, as well as the designing of new innovative ones. Reprogramming into pluripotency and lineage conversion methodologies were applied to ultimately generate RPE cells. These studies open new avenues for the establishment of cell replacement therapies and, more straightforwardly,raise the possibility of modelling retinal degenerations with underlying RPE defects in apetri dish, particularly CHM.

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Este trabalho aborda a conceito de desordem psíquica na obra de Galeno (129-216). A primeira parte enquadra o pensamento de Galeno na visão da Filosofia e Medicina em vigor no início do séc. II d.C. De seguida descrevo a concepção Hipocrática de epilepsia, e a abordagem que Platão desenvolve no Timeu e Fedro acerca da loucura, para de seguida abordar a concepção de doença em Galeno, onde são analisados os conceitos de nosêma, diathesis, pathos e energeia. Após este excurso descrevo o ponto de vista de Galeno acerca da controvérsia sobre a localização da parte dirigente da alma (hêgemonikon) que se dividia entre defensores do encefalocentrismo (Platão, Hipócrates e Herófilo) e do cardiocentrismo (Aristóteles e os Estóicos). De modo a aprofundar a compreensão de Galeno acerca deste tema descrevo o trabalho anatómico-fisiológico desenvolvido pelos médicos Alexandrinos Erasistrato e Herófilo, activos no sec. III a. C., que descobriram, através de dissecação de animais e muito provavelmente de humanos, o papel dos nervos e tendões nas atividades cognitivas e sensório-motoras. Esta foi uma descoberta central para a argumentação de Galeno acerca da interacção mente-corpo assim como para a descrição das desordens psíquicas. Posteriormente apresento a metodologia de Galeno no que concerne ao processo de diagnóstico e etiologia, essencial para se compreender como é possível aceder a ‘entidades’ não visíveis, como o hêgemonikon e as suas diferentes faculdades: ‘imaginação’, memória e raciocínio. Por fim, analiso alguns casos clínicos de pacientes afectados por desordens do hêgemonikon, a saber: phrenitis, mania e melancolia. Os principais textos objecto de análise são: Acerca dos Lugares Afectados, Acerca das Teses de Hipócrates e Platão e Que as Faculdades da Alma Seguem as Disposições do Corpo. Todavia, outros textos de Galeno serão convocados consoante a necessidade de analisar os conceitos que me proponho compreender, entre eles Acerca do Método Terapêutico e Acerca da Utilidade das Partes.

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Carcinoembryonic antigen (CEA), immunologically identical to CEA derived from colonic carcinoma, was identified and purified from perchloric acid (PCA) extracts of bronchial and mammary carcinoma. CEA extracted from bronchial and mammary carcinoma was quantitated by single radial immunodiffusion and was found to be in average about 50-75 times less abundant in these tumors than in colonic carcinoma. CEA could also be detected in one normal breast in lactation and at lower concentrations in normal lung (1000-4000 times lower than in colonic carcinoma). The small amounts of CEA present in normal tissues are distinct from the glycoprotein of small mol. wt showing only partial identity with CEA, that we recently identified and extracted in much larger quantities from normal lung and spleen. The demonstration of the presence of CEA in non digestive carcinoma by classical gel precipitation analysis suggests that the CEA detected in the plasma of such patients by radioimmunoassay is also identical to colonic carcinoma CEA. Our comparative study of plasma CEA from bronchial and colonic carcinoma, showing that CEA from both types of patient has the same elution pattern on Sephadex G-200 and gives parallel inhibition curves in the radioimmunoassay, is in favor of this hypothesis. However, it should not be concluded that all positive CEA radioimmunoassay indicate the presence of an antigen identical to colonic carcinoma CEA. A word of warning concerning the interpretation of radioimmunoassay is required by the observation that the addition of mg amounts of PCA extract of normal plasma, cleared of CEA by Sephadex filtration, could interfere in the test and mimic the presence of CEA.