889 resultados para inhibitor agent


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The existing parking simulations, as most simulations, are intended to gain insights of a system or to make predictions. The knowledge they have provided has built up over the years, and several research works have devised detailed parking system models. This thesis work describes the use of an agent-based parking simulation in the context of a bigger parking system development. It focuses more on flexibility than on fidelity, showing the case where it is relevant for a parking simulation to consume dynamically changing GIS data from external, online sources and how to address this case. The simulation generates the parking occupancy information that sensing technologies should eventually produce and supplies it to the bigger parking system. It is built as a Java application based on the MASON toolkit and consumes GIS data from an ArcGis Server. The application context of the implemented parking simulation is a university campus with free, on-street parking places.

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Cryptococcus gattii causes meningoencephalitis in immunocompetent hosts, occurring endemically in some tropical and subtropical regions. Recently, this fungus was involved in an outbreak in Vancouver Island and British Columbia (Canada). In this temperate region, the VGII type is predominant. The paper describes an autochthonous case of meningoencephalitis by C. gattii VGII in a previously health child in Rio de Janeiro, considered nonendemic region of Brazil. The fungus was identified by biochemical tests and the molecular type was determined by URA5-RFLP. The present report highlights the need for clinical vigilance for primary cryptococcal meningitis in nonendemic areas.

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This dissertation aims to guarantee the integration of a mobile autonomous robot equipped with many sensors in a multi-agent distributed and georeferenced surveillance system. The integration of a mobile autonomous robot in this system leads to new features that will be available to clients of surveillance system may use. These features may be of two types: using the robot as an agent that will act in the environment or by using the robot as a mobile set of sensors. As an agent in the system, the robot can move to certain locations when alerts are received, in order to acknowledge the underlying events or take to action in order to assist in resolving this event. As a sensor platform in the system, it is possible to access information that is read from the sensors of the robot and access complementary measurements to the ones taken by other sensors in the multi-agent system. To integrate this mobile robot in an effective way it is necessary to extend the current multi-agent system architecture to make the connection between the two systems and to integrate the functionalities provided by the robot into the multi-agent system.

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Digital Businesses have become a major driver for economic growth and have seen an explosion of new startups. At the same time, it also includes mature enterprises that have become global giants in a relatively short period of time. Digital Businesses have unique characteristics that make the running and management of a Digital Business much different from traditional offline businesses. Digital businesses respond to online users who are highly interconnected and networked. This enables a rapid flow of word of mouth, at a pace far greater than ever envisioned when dealing with traditional products and services. The relatively low cost of incremental user addition has led to a variety of innovation in pricing of digital products, including various forms of free and freemium pricing models. This thesis explores the unique characteristics and complexities of Digital Businesses and its implications on the design of Digital Business Models and Revenue Models. The thesis proposes an Agent Based Modeling Framework that can be used to develop Simulation Models that simulate the complex dynamics of Digital Businesses and the user interactions between users of a digital product. Such Simulation models can be used for a variety of purposes such as simple forecasting, analysing the impact of market disturbances, analysing the impact of changes in pricing models and optimising the pricing for maximum revenue generation or a balance between growth in usage and revenue generation. These models can be developed for a mature enterprise with a large historical record of user growth rate as well as for early stage enterprises without much historical data. Through three case studies, the thesis demonstrates the applicability of the Framework and its potential applications.

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Introduction Over the last recent years, the number of Q fever cases have has increased throughout the world. An epidemiological investigation was performed in the area in which the first molecular documentation of Q fever in Brazil was previously reported. Methods Indirect immunofluorescence assay (IFA) and PCR of Coxiella burnetii targeting the htpAB gene were performed in samples from 14 dogs (blood); 1 cat (blood); 10 goats (blood, milk, vaginal swab and anal swab); 3 sheep (blood); and 2 horses (blood). Results Two dogs, two sheep and five goats were seroreactive. DNA was amplified from 6 milk and 2 blood samples from goats and from dogs, respectively. The sequence of the amplicons exhibited 99% sequence similarity with the homologous sequence of the htpAB gene of C. burnetii RSA 331 (GenBank - CP000890). Conclusions The results confirm C. burnetii infection in animals in Rio de Janeiro and reinforce the need for the surveillance of Q fever in Brazil.

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Throughout recent years, there has been an increase in the population size, as well as a fast economic growth, which has led to an increase of the energy demand that comes mainly from fossil fuels. In order to reduce the ecological footprint, governments have implemented sustainable measures and it is expected that by 2035 the energy produced from renewable energy sources, such as wind and solar would be responsible for one-third of the energy produced globally. However, since the energy produced from renewable sources is governed by the availability of the respective primary energy source there is often a mismatch between production and demand, which could be solved by adding flexibility on the demand side through demand response (DR). DR programs influence the end-user electricity usage by changing its cost along the time. Under this scenario the user needs to estimate the energy demand and on-site production in advance to plan its energy demand according to the energy price. This work focuses on the development of an agent-based electrical simulator, capable of: (a) estimating the energy demand and on-site generation with a 1-min time resolution for a 24-h period, (b) calculating the energy price for a given scenario, (c) making suggestions on how to maximize the usage of renewable energy produced on-site and to lower the electricity costs by rescheduling the use of certain appliances. The results show that this simulator allows reducing the energy bill by 11% and almost doubling the use of renewable energy produced on-site.

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ABSTRACTINTRODUCTION:Cryptococcosis is an invasive disease acquired by inhalation of infectious propagules from the environment. Currently, compulsory notification of the spread of this disease is not required in Colombia. However, reporting of human immunodeficiency virus (HIV)/acquired immune deficiency syndrome cases to the National Surveillance System has suggested that there is a growing population at risk of contracting cryptococcosis. Few studies have described the occurrence of cryptococcosis in Colombia. Therefore, in this study, we examined the pathology of this disease in Atlántico, Colombia and determined the distributions of Cryptococcus neoformans and Cryptococcus gattii in the environment.METHODS:Clinical samples/isolates were gathered from cases of cryptococcosis previously diagnosed at health institutions in Atlántico, and surveys were completed by clinicians. The environmental study considered 32 sampling points and three tree species, i.e., Quickstick ( Gliricidia sepium ), Almond ( Terminalia catappa ), and Pink trumpet ( Tabebuia rosea ). Environmental and clinical samples/isolates were analyzed for phenotypic and genotypic confirmation.RESULTS:From 1997-2014, 41 cases of cryptococcosis were reported. The mean patient age was 40.5 years (range: 18-63 years); 76% were men, and 78% were HIV positive. Isolation was possible in 38 cases ( C. neoformans , molecular type VNI in 37 cases and C. gattii , molecular type VGI in one case). In 2012-2014, 2,068 environmental samples were analyzed with a positivity of 0.4% ( C. neoformans , molecular type VNI) in Almond and Pink trumpet trees.CONCLUSIONS:Cryptococcus neoformans , molecular type VNI had a higher prevalence than C. gattii and was associated with human exposure and the pathogenesis of cryptococcosis in this geographical region.

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The ideal agent for producing pleurodesis has not been identified. Talc, the most commonly used, poses several problems. Another possibility is silver nitrate, which was widely used in the past. PURPOSE: To determine the influence of the intrapleural instillation of lidocaine in producing a pleurodesis with silver nitrate, to define the effect of lidocaine in the maturation of the collagen fibers, and to confirm that the pleurodesis after silver nitrate is stronger than after talc. METHODS: We studied three groups of 8 rabbits. Two groups received 0.5% silver nitrate; in one we had previously injected 0.5 ml of 2% lidocaine. The third group received 400 mg/kg talc (2 ml). The animals were sacrificed 28 days after the injection, and the pleural spaces were assessed grossly for evidence of pleurodesis and microscopically for evidence of inflammation and fibrosis. The total amount of pleural collagen and the distribution of thick and thin collagen fibers were quantified. Collagen was identified using picrosirius red stain. RESULTS: In the two groups that received silver nitrate (without lidocaine: 3.5 + 03 and with lidocaine: 3.2 + 0.3), the macroscopic pleurodesis (scale 0 -- 4) was significantly (p = 0.001) better than that resulting from talc (1.6 + 0.2). The mean degree of pleural fibrosis induced by silver nitrate (3.5 + 0.2) was significantly (p = 0.004) higher than that induced by talc (1.9 + 0.1). The previous instillation of lidocaine resulted in a tendency for decreased amounts of fibrosis (3.1 + 0.4). The mean amount (10³mm²) of pleural collagen was significantly (p = 0.009) greater in the rabbits that received silver nitrate (116.9 + 22.7) than in those that received talc (10.7 + 3.4). The injection of lidocaine slightly reduced the collagen (80.1 + 30.3). The distribution of collagen fibers did not differ among the groups. CONCLUSION: This rabbit model clearly confirms that intrapleural silver nitrate is more effective than talc for producing pleurodesis. The previous intrapleural instillation of lidocaine results in a decreasing trend in the amount of collagen, but does not change the effectiveness of the pleural fusion or modify the process of collagen maturation.

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Triple therapy is accepted as the treatment of choice for H. pylori eradication. In industrialized countries, a proton pump inhibitor plus clarithromycin and amoxicillin or nitroimidazole have shown the best results. Our aims were: 1. To study the eradication rate of the association of a proton pump inhibitor plus tinidazole and clarithromycin on H. pylori infection in our population. 2. To determine if previous treatments, gender, age, tobacco, alcohol use, and non-steroidal anti-inflammatory drugs (NSAIDs) change the response to therapy. METHODS: Two hundred patients with peptic ulcer (upper endoscopy) and H. pylori infection (histology and rapid urease test - RUT) were included. A proton pump inhibitor (lansoprazole 30 mg or omeprazole 20 mg), tinidazole 500 mg, and clarithromycin 250 mg were dispensed twice a day for a seven-day period. Eradication was assessed after 10 to 12 weeks of treatment through histology and RUT. RESULTS: The eradication rate of H. pylori per protocol was 65% (128/196 patients). This rate was 53% for previously treated patients, rising to 76% for not previously treated patients, with a statistical difference p<0.01. No significant difference was observed regarding sex, tobacco use, alcohol consumption, and NSAID use, but for elderly patients the difference was p = 0.05. Adherence to treatment was good, and side effects were mild. CONCLUSIONS: A proton pump inhibitor, tinidazole, and clarithromycin bid for seven days resulted in H. pylori eradication in 65% of the patients. Previous treatments were the main cause of treatment failure.

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In recent years a set of production paradigms were proposed in order to capacitate manufacturers to meet the new market requirements, such as the shift in demand for highly customized products resulting in a shorter product life cycle, rather than the traditional mass production standardized consumables. These new paradigms advocate solutions capable of facing these requirements, empowering manufacturing systems with a high capacity to adapt along with elevated flexibility and robustness in order to deal with disturbances, like unexpected orders or malfunctions. Evolvable Production Systems propose a solution based on the usage of modularity and self-organization with a fine granularity level, supporting pluggability and in this way allowing companies to add and/or remove components during execution without any extra re-programming effort. However, current monitoring software was not designed to fully support these characteristics, being commonly based on centralized SCADA systems, incapable of re-adapting during execution to the unexpected plugging/unplugging of devices nor changes in the entire system’s topology. Considering these aspects, the work developed for this thesis encompasses a fully distributed agent-based architecture, capable of performing knowledge extraction at different levels of abstraction without sacrificing the capacity to add and/or remove monitoring entities, responsible for data extraction and analysis, during runtime.

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Widely used in cancer treatment, chemotherapy still faces hindering challenges, ranging from severe induced toxicity to drug resistance acquisition. As means to overcome these setbacks, newly synthetized compounds have recently come into play with the basis of improved pharmacokinetic/pharmacodynamic properties. With this mind-set, this project aimed towards the antiproliferative potential characterization of a group of metallic compounds. Additionally the incorporation of the compounds within a nanoformulation and within new combination strategies with commercial chemotherapeutic drugs was also envisaged. Cell viability assays presented copper (II) compound (K4) as the most promising, presenting an IC50 of 6.10 μM and 19.09 μM for HCT116 and A549 cell line respectively. Exposure in fibroblasts revealed a 9.18 μM IC50. Hoechst staining assays further revealed the compound’s predisposition to induce chromatin condensation and nuclear fragmentation in HCT116 upon exposure to K4 which was later demonstrated by flow cytometry and annexin V-FITC/propidium iodide double staining analysis (under 50 % cell death induction). The compound further revealed the ability to interact with major macromolecules such as DNA (Kb = 2.17x105 M-1), inducing structural brakes and retardation, and further affecting cell cycle progression revealing delay in S-phase. Moreover BSA interactions were also visible however not conclusive. Proteome profiling revealed overexpression of proteins involved in metabolic activity and underexpression of proteins involved in apoptosis thus corroborating Hoechst and apoptosis flow cytometry data. K4 nanoformulation suffered from several hindrances and was ill succeeded in part due to K4’s poor solubility in aqueous buffers. Other approaches were considered in this regard. Combined chemotherapy assays revealed high cytotoxicity for afatinib and lapatinib strategies. Lapatinib and K4 proteome profiling further revealed high apoptosis rates, high metabolic activity and activation of redundant proteins as part of compensatory mechanisms.

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RESUMO: Introdução: Tratamento do carcinoma da mama Este trabalho inicia-se com a história do tratamento do carcinoma da mama, desde os primeiros documentos que descrevem doentes com carcinoma da mama até 1950. Desde 1950 até 2000 o diagnóstico, risco e as modalidades terapêuticas usadas no tratamento das doentes são mais detalhadas com ênfase nas terapêuticas locais, regionais e sistémicas. Parte 1:Quem tratar com terapêutica sistémica adjuvante Capítulo 1: A classificação TNM não está morta no carcinoma da mama Tem sido dito que a classificação TNM não é adequada para usar como ferramenta de prognóstico e decisão terapêutica no carcinoma da mama, especialmente em doentes com carcinoma detectado através de rastreio, que tem geralmente menores dimensões. A razão desta classificação não ser adequada prendese com o facto de não estarem incluidos parâmetros biológicos na classificação TNM atual. Pusemos a hipótese de que numa população com alta percentagem de carcinoma da mama não detectado em exames de rastreio, com uma mediana de idade baixa e com alta percentagem de estadios II e III, o estadiamento clássico, pela classificação TNM, é mais descriminatório que as características biológicas na determinação do prognóstico. Para isto analisámos uma população de doentes com carcinoma da mama tratados consecutivamente na mesma instituição, durante 10 anos. Caracterizámos os fatores de prognóstico do estadiamento clássico incluídos na classificação TNM e as variantes biológicas, presentemente não incluídas na classificação TNM. Quantificámos a capacidade de cada um dos factores de prognóstico para para prever a sobrevivência. A população é de 1699 doentes com carcinoma da mama que foram tratádos com terapêutica sistémica adjuvante. Individualmente, cada um dos fatores de prognostico, clássicos ou biológicos, diferem significativamente entre doentes que sobrevivem e que não sobrevivem. Explicitamente, como previsto, doentes com tumores maiores, envolvimento dos gânglios axilares, estadios TNM mais avançados, que não expressam recetor de esrogéneo, com amplificação do gene Her2, triplos negativos ou de menor diferenciação têm menor sobrevida. Na análise multivariada, só os fatores de prognostico da classificação TNM, o grau histológico e a amplificação do gene Her2, esta última com menos significância estatistica são preditores independentes de sobrevivência. Capítulo 2: Em busca de novos factores de prognostico: Poder preditivo e mecanismo das alterações de centrossomas em carcinoma da mama Compilámos inúmeros grupos de experiências de genómica feitas em tumores primários de doentes com carcinoma da mama para as quais existe informação prognóstica. Estas experiências são feitas com o objectivo de descobrir novos factores de prognóstico. Reanalisámos os dados, repetindo a mesma pergunta: Quais são os genes com expressão diferencial estatisticamente significativa entre doentes que recaíram e doentes que não recaíram. Identificámos 65 genes nestas condições e o MKI67, o gene que codifica a proteina Ki67, estava nesse grupo. Identificámos vários genes que se sabe estarem envolvidos no processo de agregação de centrossomas. O gene que considerámos mais promissor foi a kinesina KiFC1, que já tinha sido identificada como regulador da agregação de centrossomas. Anomalias cetrossomais numéricas e estruturais têm sido observadas em neoplasias. Há dados correlacionando anolmalias centrossomais estruturais e e numéricas com o grau de malignidade e os eventos precoces da carcinogénese. Mas estas anomalias centrossomais têm um peso para a célula que deve adapatar-se ou entrará em apoptose. Os nossos resultados sugerem que existe um mecanismo adaptativo, a agregação de centrossomas, com impacto prognóstico negativo. O nosso objetivo foi quantificar o valor prognóstico das anomalias centrossomais no carcinoma da mama. Para isto usámos material de doentes dos quais sabemos a história natural. Avaliámos os genes de agregação de centrossomas, KIFC1 e TACC3, nas amostras tumorais arquivadas em parafina: primeiro com PCR (polymerase chain reaction) quantitativa e depois com imunohistoquímica (IHQ). Apenas a proteína KIFC1 foi discriminatória em IHQ, não se tendo conseguido otimizar o anticorpo da TACC3. Os níveis proteicos de KIFC1 correlacionam-se com mau prognóstico. Nas doentes que recaíram observámos, no tumor primário, maior abundância desta proteína com localização nuclear. Em seguida, demonstrámos que a agregação de centrossomas é um fenómeno que ocorre in vivo. Identificámos centrossomas agregados em amostras de tumores primários de doentes que recaíram. Tecnicamente usámos microscopia de fluorescência e IHQ contra proteínas centrossomais que avaliámos nos tumores primários arquivados em blocos de parafina. Observámos agregação de centrossomas num pequeno número de doentes que recaíram, não validámos, ainda, este fenótipo celular em larga escala. Parte 2: Como tratar com terapêutica sistémica os vários subtipos de carcinoma da mama Capítulo 3: Quantas doenças estão englobadas na definição carcinoma da mama triplo negativo? (revisão) O carcinoma da mama triplo negativo é um tumor que não expressa três proteínas: recetor de estrogénio, recetor de progesterona e o recetor do fator de crescimento epidermico tipo 2 (Her2). As doentes com estes tumores não são ainda tratadas com terapêutica dirigida, possivelmente porque esta definição negativa não tem ajudado. Sabemos apenas as alterações genéticas que estes tumores não têm, não as que eles têm. Talvez por esta razão, estes tumores são o subtipo mais agressivo de carcinoma da mama. No entanto, na prática clínica observamos que estas doentes não têm sempre mau prognóstico, além de que dados de histopatologia e epidemiologia sugerem que esta definição negativa não está a capturar um único subtipo de carcinoma da mama, mas vários. Avaliámos criticamente esta evidência, clínica, histopatológica, epidemiológica e molecular. Há evidência de heterogeneidade, mas não é claro quantos subtipos estão englobados nesta definição de carcinoma da mama triplo negativo. A resposta a esta pergunta, e a identificação do fundamento molecular desta heterogeneidade vai ajudar a melhor definir o prognóstico e eventualmente a definir novos alvos terapêuticos nesta população difícil. Capítulo 4: Terapêuica sistémica em carcinoma da mama triplo negativo (revisão) A quimioterapia é a única terapêutica sistémica disponível para as doentes com carcinoma da mama triplo negativo, ao contrário dos outros dois subtipo de carcinoma da mama que têm com a terapêutica antiestrogénica e anti Her2, importantes benefícios. Apesar de terem surgido várias opções terapêuticas para estes doentes nennhuma terapêutica dirigida foi validada pelos ensaios clínicos conduzidos, possivelmente porque a biologia deste carcinoma ainda não foi elucidada. Muitos ensaios demonstram que os tumores triplos negativos beneficiam com quimioterapia e que as mais altas taxas de resposta patológica completa à terapêutica neoadjuvante são observadas precisamente nestes tumors. A resposta patológica completa correlaciona-se com a sobrevivência. Estamos a estudar regimes adjuvantes específicos para doentes com estes tumors, mas, neste momento, regimes de terceira geração com taxanos e antraciclinas são os mais promissores. O papel de subgrupos de fármacos específicos, como os sais de platina, mantémse mal definido. Quanto às antraciclinas e taxanos, estes grupos não mostraram beneficio específico em carcinoma da mama triplo negativo quando comparado com os outros subtipos. Os próprios carcinomas da mama triplos negativos são heterogéneos e carcinomas da mama basais triplos negativos com elevada taxa de proliferação e carcinomas da mama triplos negativos surgidos em doentes com mutação germinal BRCA1 poderão ser mais sensíveis a sais de platino e menos sensíveis a taxanos. Como a definição molecular ainda não foi explicada a busca de terapêutica dirigida vai continuar. Capítulo 5: Ensaio randomizado de fase II do anticorpo monoclonal contra o recetor do fator de crescimento epidérmico tipo 1 combinado com cisplatino versus cisplatino em monoterapia em doentes com carcinoma da mama triplo negativo metastizado O recetor do fator de crescimento epidérmico tipo 1 está sobre expresso nos tumores das doentes com carcinoma da mama triplo negativo metastizado, um subtipo agressivo de carcinoma da mama. Este ensaio investigou a combinação de cetuximab e cisplatino versus cisplatino isolado em doentes deste tipo. Doentes em primeira ou segunda linha de terapêutica para doença metastizada foram randomizadas, num sistema de 2 para 1, para receber até 6 ciclos da combinação de cisplatino e cetuximab ou cisplatino isolado. Às doentes randomizadas para o braço de monoterapia podiamos, após progressão, acrescentar cetuximab ou tratá-las com cetuximab isolado. O objetivo primário foi a taxa de resposta global. Os objetivos secundários foram a sobrevivência livre de doença, a sobrevivência global e o perfil de segurança dos fármacos. A população em análise foram 115 doentes tratadas com a combinação e 58 doentes tratadas com cisplatino em monoterapia, 31 destas em quem se documentou progressão passaram a ser tratadas com um regime que incluía cetuximab, isolado ou em combinação. A taxa de resposta global foi de 20% no braço da combinaçao e de 10% no braço da monoterapia (odds ratio, 2.13). A sobrevivência livre de doença foi de 3.7 meses no braço da combinação e de 1.5 meses no braço em monoterapia (hazard ratio, 0.67). A sobrevivência global foi de 12.9 meses no braço da combinação versus 9.4 meses no braço de cisplatino. Conclui-se que, apesar de não ter sido alcançado o objectivo primário, acrescentar cetuximab, duplica a resposta e prolonga tanto a sobrevivência livre de doença como a sobrevivência global. Capítulo 6: Bloquear a angiogénese para tratar o carcinoma da mama (revisão) A angiogénese é uma característica que define a neoplasia, porque tumores com mais de 1mm precisam de formar novos vasos para poderem crescer. Desde que se descobriram as moléculas que orquestram esta transformação, que se têm procurado desenvolver e testar fármacos que interfiram com este processo. No carcinoma da mama o bevacizumab foi o primeiro fármaco aprovado pela FDA em primeira linha para tratar doença metastática. Depois foram estudados um grupo de inibidores de tirosina cinase associados aos recetores transmembranares envolvidos na angiogénese como o VEGFR, PDGFR, KIT, RET, BRAF e Flt3: sunitinib, sorafenib, pazopanib e axitinib Neste capítulo, analisaram-se e resumiram-se os dados dos ensaios clínicos das drogas anti-angiogénicas no tratamaneto do carcinoma da mama. Os ensaios de fase III do bevacizumab em carcinoma da mama mostraram uma redução na progressão de doença de 22 a 52% e aumento da sobrevivência livre de doença de 1.2 a 5.5 meses mas nunca foi demonstrado prolongamento de sobrevivência. Os ensaios de fase III em carcinoma da mama adjuvante com bevacizumab são dois e foram ambos negativos. O ensaio de fase III com o inibidor da tirosina cinase, sunitinib foi negativo, enquanto que os ensaios de fase II com os inibidores da tirosina cinase sorafenib e pazopanib melhoraram alguns indicadores de resposta e sobrevivência. A endostatina foi testada no contexto neoadjuvante com antraciclinas e melhorou a taxa de resposta, mas, mais ensaios são necessários para estabelecer este fármaco. A maioria dos ensaios clínicos dos agentes antiangiogénicos em carcinoma da mama reportaram aumento da taxa de resposta e de sobrevivência livre de doença mas nunca aumento da sobrevivência global quando comparado com quimioterapia isolada o que levou ao cepticismo a que assistimos atualmente em relação ao bloqueio da angiogénese. Ensaios clínicos selecionados em doentes específicas com objetivos translacionais relacionados com material biológico colhido, preferefencialmente em diferentes intervalos da terapêutica, serão cruciais para o bloqueio da angiogénese sobreviver como estratégia terapêutica em carcinoma da mama. Capítulo 7: A resposta à hipoxia medeia a resistência primária ao sunitinib em carcinoma da mama localmente avançado O sunitinib é um fármaco antiangiogénico que nunca foi avaliado isolado em doentes com carcinoma da mama não tratadas. O nosso objetivo foi caracaterizar a atividade do sunitinib isolado e em combinação com o docetaxel em carcinoma da mama não tratado, localmente avançado ou operável, mas de dimensão superior a 2 cm, para compreender os mecanismos de resposta. Doze doentes foram tratadas com duas semanas iniciais de sunitinib seguido de quatro ciclos de combinação de sunitinib e docetaxel. A resposta, a reistência e a toxicidade foram avaliadas de acordo com parametros clínicos, ressonância magnética nuclear, tomografia de emissão de positrões, histopatologia e perfis de expressão genómica. Detetámos resistência primária ao sunitinib na janela inicial de duas semanas, evidenciada em quatro doentes que não responderam. À data da cirurgia, cinco doentes tinham tumor viável na mama e axila, quatro tinahm tumor viável na mama e três foram retiradas do ensaio. Não houve respostas patológicas completas. A comparação dos perfis de expressão genómica entre os respondedores e os não respondedores, aos quinze dias iniciais, permitiu-nos identificar sobre expressão de VEGF e outras vias angiogénicas nos não respondedores. Especificamente, em tumores resistentes ao sunitinib isolado detectámos uma resposta transcricional à hipoxia caracterizada por sobre expressão de vários dos genes alvo do HIF1α. Neste ensaio de sunitinib isolado em doentes não tratadas com carcinoma da mama localmente avançado, encontrámos evidência molecular de resistência primária ao sunitinib possivelmente mediada por sobre expressão de genes que respondem à hipoxia. Parte 3: Quando parar a terapêutica sistémica às doentes com carcinoma da mama Capítulo 8: Agressividade terapêutica ns últimos três meses de vida num estudo retrospetivo dum centro único Incluímos todos os adultos que morreram com tumores sólidos na instituição em 2003 e foram tratados com quimioterapia para tratar neoplaias metastizadas. Colhemos dados detalhados relacionados com quimioterapia e toxicidade nos últimos três meses de vida a partir do processo clínico. Trezentas e dezanove doentes foram incluídos, a mediana de idade foi 61 anos. A mediana de sobrevivência de doença metastática foi de 11 meses. 66% (211) dos doentes foram tratados com QT nos últimos 3 meses de vida, 37% foram tratados com QT no úlimo mês de vida e 21% nas últimas duas semanas. Nos doentes que foram tratados com QT nos últimos três meses de vida, 50% começaram um novo regime terapêutico neste período e 14% começaram um novo regime no último mês. Identificámos como determinantes de tratamento com QT no fim de vida a idade jovem, o carcinoma da mama, do ovário e do pâncreas. Concluímos que administrámos QT no fim de vida frequentemente e iniciámos novos regimes terapêuticos no último mês de vida em 14% dos casos. Precisamos de aprofundar este trabalho para compreender se esta atitude agressiva resulta em melhor paliação de sintomas e qualidade de vida no fim de vida dos doentes com neoplasias disseminadas. Capítulo 9: O tratamento do carcinoma da mama no fim de vida está a mudar? Quisémos caracterizar a modificação da tendência no uso de QT e de estratégias paliativas no fim de vida das doentes com carcinoma da mama em diferentes instituições e em intervalos de tempo diferentes. Para isto selecionámos doentes que morreram de carcinoma da mama durante 6 anos, entre 2007 e 2012, num hospital geral e comparámos com as doentes que morreram de carcinoma da mama em 2003 num centro oncológico. Avaliámos um total de 232 doentes. O grupo mais recente tem 114 doentes e o grupo anterior tem 118 doentes. Usámos estatística descritiva para caracterizar QT no fim de vida e o uso de estratégias paliativas. Ambas as coortes são comparáveis em termos das características do carcinoma da mama. Observámos aumento do uso de estatégias paliativas: consulta da dor, consulta de cuidados paliativos e radioterapia paliativa no cuidado das doentes com carcinoma da mama metastizado. Evidenciámos aumento do número de mortes em serviços de cuidados paliativos. No entanto, a QT paliativa continua a ser prolongada até aos últimos meses de vida, embora tenhamos mostrado uma diminuição desta prática. Outros indicadores de agressividade como a admissão hospitalar também mostraram diminuição. Confirmámos a nossa hipótese de que há maior integração da medicina paliativa multidisciplinar e menos agressividade na terapêutica sistémica das doentes com carcinoma da mama nos últimos meses de vida. Chapter 10: Porque é que os nossos doentes são tratados com quimioterapia até ao fim da vida? (editorial) Este capítulo começa por dar o exmeplo duma jovem de 22 anos que viveu três meses após começar QT paliatva. Este caso epitomiza a futilidade terapêutica e é usado como ponto de partida para explorar as razões pelas quais administramos QT no fim de vida aos doentes quando é inútil, tóxica, logisticamente complexa e cara. Será que estamos a prescrever QT até tarde demais? Os oncologistas fazem previsões excessivamente otimistas e têm uma atitude pró terapêutica excessiva e são criticados por outros intervenientes nas instituições de saúde por isto. Crescentemente doentes, familiares, associações de doentes, definidores de políticas de saúde, jornalistas e a sociedade em geral afloram este tema mas tornam-se inconsistentes quando se trata dum doente próximo em que se modifica o discurso para que se façam terapêuticas sitémicas agressivas. Há uma crescente cultura de preservação da qualidade de vida, paliação, abordagem sintomática, referenciação a unidades de cuidados paliativos e outros temas do fim de vida dos doentes oncológicos terminais. Infelizmente, este tema tem ganhado momentum não porque os oncologistas estejam a refletir criticamente sobre a sua prática, mas porque os custos dos cuidados de saúde são crescentes e incomportáveis. Seja qual fôr o motivo, as razões que levam os oncologistas a administrar QT no fim de vida devem ser criticamente elucidadas. Mas há poucos dados para nos guiar nesta fase delicada da vida dos doentes e os que existem são por vezes irreconciliáveis, é uma revisão destes dados que foi feita neste capítulo. Conclusão: A abordagem do carcinoma da mama no futuro? Na conclusão, tenta-se olhar para o futuro e prever como será a tomada a cargo dum doente com carcioma da mama amanhã. Faz-se uma avaliação das várias àreas desde prevenção, rastreio, suscetibilidade genética e comportamental e terapêutica. Na terapêutica separa-se a terapêutica locoregional, sistémica adjuvante e da doença metastizada. Nos três últimos parágrafos a história duma mulher com um carcinoma localmente avançado que sobre expressa o recetor Her2, serve como ilustração de como devemos estar preparados para incorporar evolução, heterogeneidade e dinamismo no cuidado de doentes com carcinoma da mama. -------------------------------------------------------------------------------------------------- ABSTRACT: Introduction: Breast cancer care in the past This work starts with an overview of the treatment of breast cancer (BC). From the first reports of patients ill with BC until 1950. From 1950 until 2000, there is a more detailed account on how BC patients were treated with emphasis on the different modalities, local, regional and systemic treatments and their evolution. Part 1: Who to treat with adjuvant systemic therapy? Chapter 1: TNM is not dead in breast cancer It has been said that the current TNM staging system might not be suitable for predicting breast cancer (BC) outcomes and for making therapeutic decisions, especially for patients with screen detected BC which is smaller. The reason for this is also due to the non inclusion of tumor biology parameters in the current TNM system. We hypothesize that in a population where there is still a large abundance of non screen detected BC, with a low median age of incidence and abundance of high TNM staged lesions, biology is still second to classical staging in predicting prognosis. We analyzed a population of consecutive BC patients from a single institution during ten years. We characterized current established prognostic factors, classical staging variables included in the current TNM staging system and biological variables, currently not included in the TNM system. We quantified the capacity of individual prognostic factors to predict survival. We analyzed a population of 1699 consecutive BC patients. We found that individually both the TNM system prognostic factors and the biological prognostic factors are differing among BC survivors and dead patients in a statistically significant distribution. Explicitly, patients with larger tumors, positive nodes, higher stage lesions, ER negative, HER2 positive, TN or lower differentiation tumors show decreased survival. In the multivariate analysis we can conclude that in a population such as ours classical TNM staging variables, irrespective of tumor biological features, are still the most powerful outcome predictors. Chapter 2: Defining breast cancer prognosis: The predictive power and mechanism of centrosome alterations in breast cancer We performed a systematic analysis of the literature and compiled an extensive data set of gene expression data originated in primary tumours of BC patients with prognostic information. We analysed this data seeking for genes consistently up or down regulated in poor prognosis BC, i.e. that relapsed after initial treatment. In the course this bioinformatics analysis our lab identified 65 genes statistically significant across multiple datasets that can discriminate between relapsed and non-relapsed BC patients. Among the identified genes, we have detected genes such as MKI67, a marker of mitotic activity which is routinely used in the clinic. Unexpectedly, we also discovered several genes found to be involved in centrosome clustering, The most prominent of these is the kinesin KIFC1, also called HSET, and previously identified as regulator of centrosome clustering. Centrosome abnormalities (numerical, structural) have been observed in cancer. Indeed, compelling data has shown that cells from many cancers have multiple and abnormal centrosomes, that are either correlated with tumour malignancy or considered an early tumorigenesis event. However, extra centrosomes come at a cost and cells must be able to handle such abnormalities or otherwise die. Thus our results suggested a new mechanism of breast cancer progression with negative prognostic value. We aimed at quantifying the predictive power of centrosome clustering in BC clinical setting and at detecting this process in BC patient material. We validated the centrosome clustering genes KIFC1 and TACC3 in formalin fixed paraffin embedded (FFPE) BC patient material, using quantitative real-time PCR (RT-qPCR) technology. Our results indicate that the tested KIFC1 has a clear IHC signal (1) and that the protein expression patterns and levels correlate with prognosis, with relapsing patients having increased expression and nuclear localisation of this kinesin (2). Next we were able to show that centrosome clustering does occur in vivo. We identified centrosome amplification and clustering in breast cancer samples, and we established a fluorescence microscopy-based IHC approach by staining FFPE samples with centrosomal markers. Using this approach we have observed centrosome amplification and clustering in a small set of poor prognosis samples. By expanding the number of samples in which we have characterised the number of centrosomes, we were able to confirm our preliminary observation that centrosomes are clustered in relapsed BC. Part 2: How to treat breast cancer subtypes? Chapter 3: How many diseases is triple negative breast cancer? (review) Triple negative breast cancer is a subtype of breast cancer that does not express the estrogen receptor, the progesterone receptor and the epidermal growth factor receptor type 2 (Her2). These tumors are not yet treated with targeted therapies probably because no positive markers have been described to reliably classify them - they are described for what they are not. Perhaps for this reason, they are among the most aggressive of breast carcinomas, albeit with very heterogenous clinical behavior. The clinical observation that these patients do not carry a uniformly dismal prognosis, coupled with data coming from pathology and epidemiology, suggests that this negative definition is not capturing a single clinical entity, but several. We critically evaluate this evidence in this paper, reviewing clinical and epidemiological data, as well as molecular data. There is evidence for heterogeneity, but it is not clear how many diseases are grouped into triple negative breast cancer. Answering this question, and identifying the molecular basis of heterogeneity will help define prognosis and, eventually, the identification of new targeted therapies. Chapter 4: Systemic treatment for triple negative breast cancer (review) Chemotherapy remains the backbone of treatment for triple negative breast cancer (TNBC). Despite the appearance of new targeted and biologic agents there has been no targeted therapy validated for TNBC, possibly because the biology of TNBC has not been conclusively elucidated. Many studies have shown that TNBC derive significant benefit of chemotherapy in the neoadjuvant, adjuvant and metastatic treatment, possibly more benefit than other BC subtypes. Neoadjuvant chemotherapy studies have repeatedly shown higher response rates in TNBC than non-TNBC. Pathologic complete response has been shown to predict improved long term outcomes in BC. Although specific adjuvant regimens for TNBC are under study, third generation chemotherapy regimens utilizing dose dense or metronomic polychemotherapy are among the most effective tools presently available. The role of specific chemotherapy agents, namely platinum salts, in the treatment of TNBC remains undefined. Taxanes and anthracyclines are active in TNBC and remain important agents, but have not shown specific benefit over non-TNBC. TNBC is itself a heterogeneous group in which subgroups like basal like BC defined by higher proliferation and including those TNBC arising in BRCA1 mutation carriers may be more sensitive to platinum agents and relatively less sensitive to taxanes. The molecular characterization of TNBC is lacking and therefore the search for targeted therapy is still ongoing. Chapter 5: Randomized phase II study of the anti-epidermal growth factor receptor monoclonal antibody cetuximab with cisplatin versus cisplatin alone in patients with metastatic triple-negative breast cancer Epidermal growth factor receptor is overexpressed in metastatic triple-negative breast cancers, an aggressive subtype of breast cancer. Our randomized phase II study investigated cisplatin with or without cetuximab in this setting. Patients who had received no more than one previous chemotherapy regimen were randomly assigned on a 2:1 schedule to receive no more than six cycles of cisplatin plus cetuximab or cisplatin alone. Patients receiving cisplatin alone could switch to cisplatin plus cetuximab or cetuximab alone on disease progression. The primary end point was overall response rate (ORR). Secondary end points studied included progressionfree survival (PFS), overall survival (OS), and safety profiles. The full analysis set comprised 115 patients receiving cisplatin plus cetuximab and 58 receiving cisplatin alone; 31 patients whose disease progressed on cisplatin alone switched to cetuximab-containing therapy. The ORR was 20% with cisplatin plus cetuximab and 10% with cisplatin alone (odds ratio, 2.13). Cisplatin plus cetuximab resulted in longer PFS compared with cisplatin alone (median, 3.7 v 1.5 months; hazard ratio, 0.67. Corresponding median OS was 12.9 versus 9.4 months. While the primary study end point was not met, adding cetuximab to cisplatin doubled the ORR and appeared to prolong PFS and OS, warranting further investigation in mTNBC. Chapter 6: Blocking angiogenesis to treat breast cancer (review) Angiogenesis is a hallmark of cancer because tumors larger than 1mm need new vessels to sustain their growth. Since the discovery of the molecular players of this process and some inhibitors, that angiogenesis became a promising therapeutic target. Bevacizumab was the first molecular-targeted antiangiogenic therapy approved by the FDA and is used as first-line therapy in metastatic breast cancer. A second class of approved inhibitors (sunitinib, sorafenib, pazopanib and axitinib) include oral small-molecule tyrosine kinase inhibitors that target vascular endothelial growth factor receptors, platelet-derived growth factor receptors, and other kinases including KIT, Ret, BRAF and Flt-3, but none of these have gained approval to treat breast cancer. This review analyzes and summarizes data from clinical trials of anti-angiogenic agents in the treatment of BC. Phase III trials of bevacizumab in advanced BC have demonstrated a reduction in disease progression (22–52%), increased response rates and improvements in progression-free survival of 1.2 to 5.5 months, but no improvements in OS. Bevacizumab phase III trials in early BC have both been negative. Bevacizumab combined with chemotherapy is associated with more adverse events. Phase III trials of the tyrosine kinase inhibitor sunitinib were negative, while randomized phase II trials of sorafenib and pazopanib have improved some outcomes. Endostatin has been tested in neoadjuvant clinical trials in combination with anthracyclinebased chemotherapy in treatment-naive patients and has increased the clinical response rate, but more trials are needed to establish this drug. Most trials of anti-angiogenic agents in BC have reported improved RR and PFS but no increase in OS compared to chemotherapy alone, leading to skepticism towards blocking angiogenesis. Selected trials in selected BC populations with translational endpoints related to harvested tumor tissue and other biological material samples, preferentially at several timepoints, will be crucial if antiangiogenesis is to survive as a strategy to treat BC. Chapter 7: Does hypoxic response mediate primary resistance to sunitinib in untreated locally advanced breast cancer? The antiangiogenic drug sunitinib has never been evaluated as single agent in untreated BC patients. We aimed to characterize the activity of sunitinib, alone and with docetaxel, in untreated locally advanced or operable BC, and, to uncover the mechanisms of response. Twelve patients were treated with an upfront window of sunitinib followed by four cycles of sunitinib plus docetaxel. Response, resistance and toxicity were evaluated according to standard clinical parameters, magnetic resonance imaging, positron emission tomography, pathology characterization and gene expression profiling. We detected primary resistance to sunitinib upfront window in untreated BC, as evidenced by four non-responding patients. At surgery, five patients had viable disease in the breast and axilla, four had viable tumor cells in the breast alone and three were taken off study due to unacceptable toxicity and thus not evaluated. Early functional imaging was useful in predicting response. There were no pathologic complete responses (pCR). Comparison of gene expression profiling tumor data between early responders and non-responders allowed us to identify upregulation of VEGF and angiogenic pathways in non responders. Specifically, in tumors resistant to the single-agent sunitinib we detected a transcriptional response to hypoxia characterized by over-expression of several HIF1α target genes. In this report of single-agent sunitinib treatment of untreated localized BC patients, we found molecular evidence of primary resistance to sunitinib likely mediated by up-regulation of hypoxia responsive genes. Part 3: When to stop systemic treatment of breast cancer patients? Chapter 8: The aggressiveness of cancer care in the last three months of life: a retrospective single centre analysis. All adult patients with solid tumors who died in our hospital in 2003 and received chemotherapy for advanced cancer, were included. Detailed data concerning chemotherapy and toxicity, in the last three months of life, were collected from patientsʼ clinical charts. A total of 319 patients were included. Median age was 61 years. Median time from diagnosis of metastatic disease to death was 11 months. The proportion of patients who received chemotherapy in the last three months of life was 66% (n=211), in the last month 37% and in the last two weeks 21%. Among patients who received chemotherapy in the last three months of life, 50% started a new chemotherapy regimen in this period and 14% in the last month. There was an increased probability of receiving chemotherapy in the last three months of life in younger patients and in patients with breast, ovarian and pancreatic carcinomas. There was a large proportion of patients who received chemotherapy in the last three months of life, including initiation of a new regimen within the last 30 days. Thus, further study is needed to evaluate if such aggressive attitude results in better palliation of symptoms at the end of life. Chapter 9: Is breast cancer treatment in the end of life changing? We aimed to characterize the shifting trends in use of anti-cancer chemotherapy and palliative care approaches in the end of life of BC patients in different institutions and times. For this, we selected women that died of BC during six years, from 2007 to 2012, and were treated in a central acute care general hospital and compared it with the BC patients that died in 2003 and were treated in a large cancer center. We analyzed a total of 232 patients: the more recent group has 114 women and the older cohort has 118. We used descriptive statistics to characterize CT in the EoL and use of palliative care resources. Both populations were similar in terms of BC characteristics. We observed more palliative care resources, pain clinic, palliative care teams and palliative radiotherapy, involved in the care of MBC patients and a shift towards more deaths at hospices. Systemic anti cancer treatments continue to be prolonged until very late in patients’ lives, notwithstanding, we could show a decrease in the use of such treatments. Other indicators of aggressiveness, namely hospital admissions, also show a decrease. We confirmed our hypothesis that there is more integration of multidisciplinary palliative care and less aggressiveness in the treatment of metastatic cancer patients, specifically, use of palliative anti-cancer treatment and hospital admissions. Nonetheless, we use systemic therapy until too late with underutilization of palliative medicine. Chapter 10: Why do our patients get chemotherapy until the end of life? (editorial) The editorial starts with a clinical case of a 21 year old patient that lives three months after starting palliative chemotherapy for the first time, a case that illustrates therapeutic futility at the end of life. Why are we not ceasing chemotherapy when it is useless, toxic, logistically complex and expensive? Are we prescribing chemotherapy until too late in solid tumor patientsʼ lives? Medical oncologists have overly optimistic predictions and, excessive, treatment-prone attitude and they are criticized by other health care providers for this. Increasingly, patients, their families, advocacy groups, policy makers, journalists and society at large dwell on this topic, which is a perplexing conundrum, because sometimes they are the ones demanding not to stop aggressive systemic anticancer treatments, when it comes to their loved ones. There is a growing culture of awareness toward preserving quality of life, palliative care, symptom-directed care, hospice referral and end of life issues regarding terminal cancer patients. Sadly, this issue is gaining momentum, not because oncologists are questioning their practice but because health care costs are soaring. Whatever the motive, the reasons for administering chemotherapy at the end of life should be known. There are few and conflicting scientific data to guide treatments in this delicate setting and we review this evidence in this paper. Conclusion: What is the future of breast cancer care? This work ends with a view into the future of BC care. Looking into the different areas from prevention, screening, hereditary BC, local, regional and systemic treatments of adjuvant and metastatic patients. The last three paragraphs are a final comment where the story of a patient with Her2 positive locally advanced breast cancer is used as paradigm of evolution, heterogeneity and dynamism in the management of BC.

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This article describes the main approaches adopted in a study focused on planning industrial estates on a sub-regional scale. The study was supported by an agent-based model, using firms as agents to assess the attractiveness of industrial estates. The simulation was made by the NetLogo toolkit and the environment represents a geographical space. Three scenarios and four hypotheses were used in the simulation to test the impact of different policies on the attractiveness of industrial estates. Policies were distinguished by the level of municipal coordination at which they were implemented and by the type of intervention. In the model, the attractiveness of industrial estates was based on the level of facilities, amenities, accessibility and on the price of land in each industrial estate. Firms are able to move and relocate whenever they find an attractive estate. The relocating firms were selected by their size, location and distance to an industrial estate. Results show that a coordinated policy among municipalities is the most efficient policy to promote advanced-qualified estates. In these scenarios, it was observed that more industrial estates became attractive, more firms were relocated and more vacant lots were occupied. Furthermore, the results also indicate that the promotion of widespread industrial estates with poor-quality infrastructures and amenities is an inefficient policy to attract firms.

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Ageing and skin exposure to UV radiation induces production and activation of matrix metalloproteinases (MMPs) and human neutrophil elastase (HNE). These enzymes are known to break down the extracellular matrix (ECM) which leads to wrinkle formation. Here, we demonstrated the potential of a solid-in-oil nanodispersion containing a competitive inhibitor peptide of HNE mixed with hyaluronic acid (HA), displaying 158 nm of mean diameter, to protect the skin against the ageing effects. Western blot analysis demonstrated that activation of MMP-1 in fibroblasts by HNE treatment is inhibited by the solid-in-oil nanodispersion containing the peptide and HA. The results clearly demonstrate that solid-in-oil nanodispersion containing the HNE inhibitor peptide is a promising strategy for anti-ageing effects. This effect can be seen particularly by ECM regulation by affecting fibroblasts. The formulation also enhances the formation of thicker bundles of actin filaments.

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Dissertação de mestrado em Bioquímica Aplicada (área de especialização em Biomedicina)