963 resultados para Citrate precursor


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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

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Blastic plasmacytoid dendritic cell neoplasm is a rare and aggressive hematodermic neoplasia with frequent cutaneous involvement and leukemic dissemination. We report the case of a 76-year-old man with a 2 month history of violaceous nodules and a tumor with stony consistency, located on the head, and mandibular, cervical and supraclavicular lymphadenopathies. Multiple thoracic and abdominal adenopathies were identified on computerized tomography. Flow cytometry analysis of the skin, lymph node and bone marrow biopsies demonstrated the presence of plasmocytoid dendritic cell neoplastic precursor cells (CD4+, CD45+, CD56+ and CD123+ phenotype). After initial clinical and laboratorial complete remission with chemotherapy, the patient died due to relapse of the disease associated with the appearance of a cervical mass with medullary compromise.

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A síndrome de Smith-Lemli-Opitz (SLOS) é uma síndrome polimalformativa de transmissão autossómica recessiva causada por um défice metabólico da biossíntese do colesterol, que se caracteriza por dismorfias craniofaciais, anomalias congénitas de vários órgãos (salientando-se as do esqueleto e do aparelho urogenital), restrição de crescimento intra-uterino (RCIU), alterações comportamentais e atraso mental. É causada por mutações no gene DHCR7, que codifica para a enzima 7-dehidrocolesterol reductase, responsável pelo último passo da via metabólica da síntese do colesterol. A SLOS caracteriza-se por níveis diminuídos de colesterol e concentrações altas do seu precursor, 7-dehidrocolesterol, no sangue e tecidos. Procedeu-se a uma análise comparativa dos fenótipo e genótipo de quinze casos de SLOS de origem portuguesa, e são tecidas considerações quanto às dificuldades e limitações inerentes ao diagnóstico, e ao facto de esta doença hereditária do metabolismo dever ser considerada no diagnóstico diferencial das situações de (i) hipocolesterolémia, (ii) RCIU e (iii) síndromes polimalformativas,(especialmente quando crianças com atraso de crescimento apresentam simultaneamente sindactilia do segundo e terceiro dedos do pé e microcefalia e/ou narinas antevertidas entre outras anomalias).

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Adult B-cell acute lymphoblastic leukemia remains a major therapeutic challenge, requiring a better characterization of the molecular determinants underlying disease progression and resistance to treatment. Here, using a phospho-flow cytometry approach we show that adult diagnostic B-cell acute lymphoblastic leukemia specimens display PI3K/Akt pathway hyperactivation, irrespective of their BCR-ABL status and despite paradoxically high basal expression of PTEN, the major negative regulator of the pathway. Protein kinase CK2 is known to phosphorylate PTEN thereby driving PTEN protein stabilization and concomitant PTEN functional inactivation. In agreement, we found that adult B-cell acute lymphoblastic leukemia samples show significantly higher CK2 kinase activity and lower PTEN lipid phosphatase activity than healthy controls. Moreover, the clinical-grade CK2 inhibitor CX-4945 (Silmitasertib) reversed PTEN levels in leukemia cells to those observed in healthy controls, and promoted leukemia cell death without significantly affecting normal bone marrow cells. Our studies indicate that CK2-mediated PTEN posttranslational inactivation, associated with PI3K/Akt pathway hyperactivation, are a common event in adult B-cell acute lymphoblastic leukemia and suggest that CK2 inhibition may constitute a valid, novel therapeutic tool in this malignancy.

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RESUMO: A doença de Alzheimer (AD) é a forma mais comum de demência em todo o mundo e sua prevalência deverá duplicar até 2050. Os mecanismos precisos responsáveis pela AD são desconhecidas mas as características histopatológicas estão bem caracterizadas. A hipótese mais importante para a perda neuronal e declínio cognitivo na AD é a cascata amilóide que indica que AD é o resultado da sobreprodução de beta amilóide (Aβ) e / ou remoção ineficaz; a acumulação do BA no cérebro seria o passo crítico na patogénese da AD. Actualmente, a identificação de proteínas que se ligam ao Aβ e modulam a sua agregação e neurotoxicidade pode proporcionar a base para novas abordagens terapêuticas. A apolipoproteína AI (ApoA-I), o principal componente das HDL humanas, interage com o domínio extracelular da proteína precursora de amilóide (APP), bem como com o Aβ. Estudos epidemiológicos têm mostrado uma diminuição acentuada da ApoA-I plasmática em doentes com AD, com uma correlação inversa entre o nível de ApoA-I e o risco de AD. Este trabalho pretende apresentar um projecto que tem como objectivo investigar se os anticorpos anti-apo AI podem impedir a formação de complexos Aβ / ApoA-I, bloqueando o efeito protector da ApoA-I. A hipótese baseia-se na possibilidade dos doentes com AD terem anticorpos anti-ApoA-I plasmáticos e de estes poderem interferir com a formação do complexo no LCR.------- ABSTRACT:Alzheimer’s disease (AD) is the most common form of dementia world-wide and its prevalence is expected to double by the year 2050. The precise mechanisms responsible for AD are unknown but the histopathologic features are well-characterised. The most compelling hypothesis for neuronal loss and cognitive decline in AD is the amyloid cascade hypothesis which states that AD is the result of amyloid beta (Aβ) overproduction and/or ineffective clearance and its accumulation in the brain would be the critical step in AD pathogenesis. Currently, identification of proteins that bind Aβ and modulate its aggregation and neurotoxicity could provide the basis for novel treatment approaches. Apolipoprotein A-I (ApoA-I), the main constituent of human HDL, ApoA-I interacts with the extracellular domain of amyloid precursor protein (APP), as well as with Aβ itself. Epidemiological studies have shown a marked decrease of plasma ApoA-I levels in AD patients, with an inverse correlation between the ApoA-I level and the risk of AD. This work intends to present a project that aims to investigate if anti-ApoA-I antibodies may prevent the formation of the Aβ /ApoA-I complex and by doing so blocking the protective effect of ApoA-I in AD. We base the hypothesis on the possibility that patients with AD might have anti-ApoA-I antibodies in plasma and that these can interfere with the complex formation in the cerebrospinal fluid (CSF).

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Estudou-se a ação do suco gástrico artificial e suco duodenal humano sobre a vacina BCG, bem como a absorção e destino desta após administração intragástrica em camundongos. O contato de 2 horas do bacilo com o suco gástrico provocou uma diminuição significante do consumo de oxigênio e uma moderada perda da viabilidade. O suco duodenal induziu marcante decréscimo da respiração bacilar egrande redução da viabilidade. O BCG foi marcado com carbono-14 usando-se 14C-glicerol como precursor dos lipidios micobacterianos. Níveis similares de radioatividade foram obtidos nos órgãos dos animais, 24 horas após administração intragástrica de 14C- BCG, 14C-BCG rompido por ultra-som e 14C-glicerol. Os níveis de 14C-BCG permaneceram estáveis do 6º ao 24º dia, enquanto o sonicado de 14C-BCG e 14C-glicerol definiram um processo de decaimento biológico. As curvas de biodecaimento no intestino delgado e no fígado indicaram que o processo de absorção foi desencadeado rapidamente e alcançou seu nível máximo às 24 horas, decaindo em seguida de acordo com a complexidade química do material dado aos camundongos. Não foram isolados bacilos viáveis dos órgãos dos animais que receberam BCG não marcado. Pode-se concluir, portanto, que a maioria dos bacilos foram absorvidos intactos mas não viáveis.

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The authors evaluated the isoniazid acetylating phenotype and measured hematocrit, hemoglobin, glucose-6-phosphate dehydrogenase and glutathione reductase activities plus serum sulfadoxin levels in 39 patients with paracoccidioidomycosis (33 males and 6 females) aged 17 to 58 years. Twenty one (53.84%) of the patients presented a slow acetylatingphenotype and 18(46.16%) a fast acetylating phenotype. Glucose-6-phosphate- dehydrogenase (G6PD) acti vity was decreased in 5(23.80%) slow acetylators and in 4(22.22%) fast acetylators. Glutathione reductase activity was decreased in 14 (66.66%) slow acetylators and in 12 (66.66%) fast acetylators. Serum levels of free and total sulfadoxin Were higher in slow acetylator (p < 0.02). Analysis of the resultspermitted us to conclude that serum sulfadoxin levels are related to the acetylatorphenotype. Furthermore, sulfadoxin levels were always above 50 µg/ml, a value considered therapeutic. Glutathione reductase deficiency observed in 66% of patients may be related to the intestinal malabsorption of nutrients, among them riboflavin, a FAD precursor vitamin, inpatients with paracoceidioidomycosis.

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Dissertação para obtenção do Grau de Mestre em Engenharia Química e Bioquímica

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Dissertação para obtenção do Grau de Mestre em Biotecnologia

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Tese de Doutoramento apresentada ao Departamento de Filología Moderna, Facultad de Filología, Universidad de Salamanca

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Do vasto rol de manifestações heráldicas da vila de Óbidos, destaca-se, pela sua monumentalidade e beleza, a pedra de armas do paço dos alcaides, tanto mais visível quanto se situa no histórico edifício que funcionou como precursor da ideia de recuperação e valorização do património histórico ao serviço de um aproveitamento turístico e comercial, uma vez que se trata da primeira pousada nacional inaugurada em Portugal. A análise de tão importante monumento heráldico dividir-se-á em duas partes: a primeira relativa à representação das armas reais; a segunda sobre as insígnias dos Noronhas. Além do estudo destas duas armas, procurar-se-á compreender o significado da sua representação conjunta, logrando destarte fornecer uma interpretação simbológica da manifestação em estudo.

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This paper addresses the study of a mosaic discovered in 2007 at the archaeological site of Alter do Chão, Portugal, whose central panel represents the penultimate scene narrated in the last Book of the Æneid – a Roman epic composed by the poet Publius Vergilius Maro (70 BC – AD 19), at the request of Gaius Julius Cæsar Octavianus Augustus (63 BC – AD 14): it shows the very moment when Turnus, the Latin king of the Rutuli, kneels before Æneas, considered the precursor to the foundation of Rome (Virgil, Æneid, XII, 926-950).

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The term res publica (literally “thing of the people”) was coined by the Romans to translate the Greek word politeia, which, as we know, referred to a political community organised in accordance with certain principles, amongst which the notion of the “good life” (as against exclusively private interests) was paramount. This ideal also came to be known as political virtue. To achieve it, it was necessary to combine the best of each “constitutional” type and avoid their worst aspects (tyranny, oligarchy and ochlocracy). Hence, the term acquired from the Greeks a sense of being a “mixed” and “balanced” system. Anyone that was entitled to citizenship could participate in the governance of the “public thing”. This implied the institutionalization of open debate and confrontation between interested parties as a way of achieving the consensus necessary to ensure that man the political animal, who fought with words and reason, prevailed over his “natural” counterpart. These premises lie at the heart of the project which is now being presented under the title of Res Publica: Citizenship and Political Representation in Portugal, 1820-1926. The fact that it is integrated into the centenary commemorations of the establishment of the Republic in Portugal is significant, as it was the idea of revolution – with its promise of rupture and change – that inspired it. However, it has also sought to explore events that could be considered the precursor of democratization in the history of Portugal, namely the vintista, setembrista and patuleia revolutions. It is true that the republican regime was opposed to the monarchic. However, although the thesis that monarchy would inevitably lead to tyranny had held sway for centuries, it had also been long believed that the monarchic system could be as “politically virtuous” as a republic (in the strict sense of the word) provided that power was not concentrated in the hands of a single individual. Moreover, various historical experiments had shown that republics could also degenerate into Caesarism and different kinds of despotism. Thus, when absolutism began to be overturned in continental Europe in the name of the natural rights of man and the new social pact theories, initiating the difficult process of (written) constitutionalization, the monarchic principle began to be qualified as a “monarchy hedged by republican institutions”, a situation in which not even the king was exempt from isonomy. This context justifies the time frame chosen here, as it captures the various changes and continuities that run through it. Having rejected the imperative mandate and the reinstatement of the model of corporative representation (which did not mean that, in new contexts, this might not be revived, or that the second chamber established by the Constitutional Charter of 1826 might not be given another lease of life), a new power base was convened: national sovereignty, a precept that would be shared by the monarchic constitutions of 1822 and 1838, and by the republican one of 1911. This followed the French example (manifested in the monarchic constitution of 1791 and in the Spanish constitution of 1812), as not even republicans entertained a tradition of republicanism based upon popular sovereignty. This enables us to better understand the rejection of direct democracy and universal suffrage, and also the long incapacitation (concerning voting and standing for office) of the vast body of “passive” citizens, justified by “enlightened”, property- and gender-based criteria. Although the republicans had promised in the propaganda phase to alter this situation, they ultimately failed to do so. Indeed, throughout the whole period under analysis, the realisation of the potential of national sovereignty was mediated above all by the individual citizen through his choice of representatives. However, this representation was indirect and took place at national level, in the hope that action would be motivated not by particular local interests but by the common good, as dictated by reason. This was considered the only way for the law to be virtuous, a requirement that was also manifested in the separation and balance of powers. As sovereignty was postulated as single and indivisible, so would be the nation that gave it soul and the State that embodied it. Although these characteristics were common to foreign paradigms of reference, in Portugal, the constitutionalization process also sought to nationalise the idea of Empire. Indeed, this had been the overriding purpose of the 1822 Constitution, and it persisted, even after the loss of Brazil, until decolonization. Then, the dream of a single nation stretching from the Minho to Timor finally came to an end.

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Three different treatments were applied on several specimens of dolomitic and calcitic marble, properly stained with rust to mimic real situations (the stone specimens were exposed to the natural environment for about six months in contact with rusted iron). Thirty six marble specimens, eighteen calcitic and eighteen dolomitic, were characterized before and after treatment and monitored throughout the cleaning tests. The specimens were characterized by SEM-EDS (Scanning Electron Microscopy coupled with Energy Dispersion System), XRD (XRay Diffraction), XRF (X-Ray Fluorescence), FTIR (Fourier Transform Infrared Spectroscopy) and color measurements. It was also made a microscopic and macroscopic analysis of the stone surface along with the tests of short and long term capillary absorption. A series of test trials were conducted in order to understand which concentrations and contact times best suits to this purpose, to confirm what had been written to date in the literature. We sought to develop new methods of treatment application, skipping the usual methods of applying chemical treatments on stone substrates, with the use of cellulose poultice, resorting to the agar, a gel already used in many other areas, being something new in this area, which possesses great applicability in the field of conservation of stone materials. After the application of the best methodology for cleaning, specimens were characterized again in order to understand which treatment was more effective and less harmful, both for the operator and the stone material. Very briefly conclusions were that for a very intense and deep penetration into the stone, a solution of 3.5% of SDT buffered with ammonium carbonate to pH around 7 applied with agar support would be indicated. For rust stains in its initial state, the use of Ammonium citrate at a concentration of 5% buffered with ammonium to pH 7 could be applied more than once until satisfactory results appear.