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- Prevalência das lesões músculo-esqueléticas no setor da construção civilPublication . Pereira, Joana José Sousa; Cavaco, Adriana; Fontes, Ana PaulaA construção civil é um setor de alto risco devido aos esforços físicos exigentes e fatores ergonómicos. Destaca- se a diversidade de profissionais envolvidos e a intensa mão-de-obra, com impacto na saúde ocupacional dos trabalhadores. As lesões músculo-esqueléticas são comuns neste setor e afetam a segurança, saúde e bem-estar dos trabalhadores. Este estudo pretendeu avaliar a sintomatologia das lesões músculo-esqueléticas relacionadas com o trabalho na construção civil e a sua relação com a perceção de qualidade de vida. Realizou-se um estudo observacional, analítico, transversal e correlacional, numa amostra de 82 trabalhadores da construção civil do sexo masculino, em relação a variáveis sociodemográficas e de saúde, e também a perceção da qualidade de vida. Os sintomas músculo-esqueléticos e a intensidade da dor em diferentes regiões corporais foram avaliados através do questionário nórdico músculo-esquelético e a perceção de qualidade de vida relacionada com a saúde por meio do questionário SF-36. Verificou-se que, nos últimos 12 meses, a maior prevalência de sintomatologia foi na região lombar (53,7%) e joelhos (42,7%), e também que 35% da amostra apresentou incapacidade para o trabalho, em algum período, nos últimos 12 meses, devido a dor lombar. Quanto à intensidade da dor, a região lombar foi dos segmentos corporais que mais se correlacionaram com os domínios do questionário SF36, sendo que os participantes que demonstraram maior intensidade de dor na região lombar também apresentaram resultados menos favoráveis nos domínios de “Desempenho Físico”, “Dor”, “Vitalidade”, “Função Social” e “Saúde Mental”. Concluiu-se que a sintomatologia músculo-esquelética, nomeadamente, pela sua associação à intensidade da dor, encontra-se intrinsecamente relacionada com a qualidade de vida percebida pelos trabalhadores, no entanto, este estudo indica que os trabalhadores deste setor desfrutam de boas condições de qualidade de vida, apesar de ser necessário considerar a influencia do esforço mental e psicológico, associado às tarefas repetitivas.
- Monitorização de pigmentos na produção de microalgasPublication . Costa, Nicole Marques; Bragança, José; Carneiro, MarianaAs microalgas e as cianobactérias representam um grupo de organismos fotossintéticos que são ricos em pigmentos, tais como a clorofila, carotenoides e ficobiliproteínas. Estes pigmentos, como por exemplo a fucoxantina, têm um elevado interesse no mercado da cosmética, nutracêutica e farmacêutica. A fucoxantina é um carotenoide (xantofila) que contém uma elevada procura devido às suas propriedades anti-inflamatórias, antioxidantes, antiobesidade e antidiabética. A fucoxantina pode ser encontrada no meio natural em macro- e microalgas, mas a sua produção sintética não é viável por razões económicas. Devido à importância destes pigmentos, torna-se importante monitorizar a variação do conteúdo destes pigmentos na biomassa num contexto de produção industrial para melhorar a sua produtividade. A Necton S.A. é uma empresa produtora de microalgas inclusive de espécies que contêm um alto conteúdo de fucoxantina, como a Tisochrysis lutea (haptófita) e a Phaeodactylum tricornutum (diatomácea), que caracteriza as células com uma tonalidade acastanhada. Este relatório tem dois objetivos principais, primeiro testar um método de quantificação espetrofotométrica de fucoxantina, que será validado com uma quantificação standard por cromatografia líquida (HPLC), de forma a obter um método mais rápido de quantificação. Após a seleção do melhor método, o segundo objetivo foca-se na monitorização do conteúdo de fucoxantina das microalgas ao longo da produção em fotobioreatores tubulares elucidará o efeito dos diferentes fatores abióticos como a luz e a temperatura na produção deste pigmento. Estes objetivos ajudarão a otimizar a produtividade de fucoxantina e a maximizar a valorização da biomassa final.
- Characterization of the role of H2S in neuronal differentiation in Trisomy 21Publication . Marques, Vera; Araújo, Inês; Simão, SóniaDown syndrome (DS) is caused by trisomy of chromosome 21 and is one of the most prevalent aneuploidies compatible with life. The characteristics of DS include congenital heart defects, craniofacial abnormalities, gastrointestinal anomalies, leukemia, seizures, early onset of Alzheimer´s disease, and cognitive impairment among others. Disturbances in the neurological signal processing during critical stages of neurogenesis can affect proliferation, migration, and differentiation of stem cells which may be responsible for the mental impairment of these individuals. These features are important to understanding how DS's brain development is affected. The gene coding for cystathionine-beta-synthase (CBS) is present in chromosome 21 with an extra copy in individuals with DS. CBS is one of the enzymes responsible for the cellular production of hydrogen sulfide (H2S). This is a ubiquitous small gaseous signaling molecule that plays an important role in many physiological processes. However, the contribution of H2S to the abnormal neurodevelopment of DS individuals has not been addressed and is currently under investigation under the Araújo lab. In this study, we aimed to evaluate the contribution of H2S in DS fibroblasts prior to reprogramming these cells into induced pluripotent stem cells (iPSC) to be used in the future as a human cellular model to address the role of H2S in neuronal differentiation in DS. To accomplish this objective, fibroblasts collected from Down Syndrome patients and healthy donors were obtained and H2S production was assessed by time-lapse imaging using a fluorescent probe selective for H2S. The fibroblasts were afterward reprogrammed into iPS cells. The levels of intracellular H2S were higher in the DS cell line when compared to the healthy donor cell line. iPS cells from the DS individuals and the healthy donor fibroblasts were reprogrammed with success and both cell lines expressed the main pluripotency markers Sox2, Nanog, and Oct4 observed by immunocytochemistry and flow cytometry analysis. The data obtained in this work and the iPS lines developed will allow in the future the establishment of an important cellular model to study how H2S affects neurodevelopment in DS.
- Analysis of mutational allelic imbalances’ Influence on drug treatment responsePublication . Fontes, Melissa Ferreira; Maia, Ana-Teresa; Ferreira, Bibiana I.Breast cancer exhibits significant heterogeneity across various dimensions concerning histological and molecular classification, as well as mutational profile and clinical outcome. Defining treatment courses is likewise a complex task, as patients share similar features but different clinical prognoses. Nowadays, prognostic assessment tries to capture the morphologic and genetic variation within breast tumours, employing a variety of multigene molecular tests focusing on measuring gene expression of a specific gene panel, to predict patient outcome. In current clinical practice, the assessment of the PIK3CA mutational status is a routine procedure for hormone-receptor positive, HER2 negative metastatic breast cancers. Evaluation of gain-of-function mutations in the PIK3CA gene within this patient cohort helps to identify individuals who may benefit from systemic treatment with alpelisib, a PI3Kα-specific inhibitor. Previous studies have demonstrated that widespread allelic imbalances in the expression of somatic mutations in PIK3CA are associated with prognosis in breast cancer. Particularly, preferential expression of PIK3CA’s mutated allele is associated with poorer prognosis. Here, we hypothesise that differential allelic expression of PIK3CA mutations influences protein levels in breast cancer cells, thereby potentially affecting drug treatment response. We aimed to create an inducible PIK3CA breast cell-based tool capable of inducing different levels of PIK3CA mutational expressions as a platform to evaluate the impact of mutational expression levels on the response to PI3K-targeted therapies. Our goal was to create a cell-based system to precisely identify patients eligible for PI3K-α inhibitor therapies by modelling PIK3CA mutant expression dosages and assessing cell drug response. Our results show that we successfully generated a plasmid capable of constitutively expressing the wild-type isoform of the PIK3CA gene and also three inducible plasmids that can express three different levels of each PIK3CA mutant in a controlled manner. These plasmids constitute the tools required to transfect breast cell lines and generate the PIK3CA inducible system. Once the system is not yet created, our hypothesis is still subject to proof.
- Modelling left ventricular noncompaction cardiomyopathy in cardioidsPublication . Correia, Cátia Dias; Calado, Sofia; Bragança, JoséCongenital heart defects are the most common deficiency in new-borns. Specifically, a failure during myocardial compaction can lead to excessive trabeculation and intertrabecular recesses seen in left ventricular noncompaction (LVNC). Due to heterogeneity found in patients, more in-depth molecular research, with better disease models, is necessary to identify underlying genetic pathways and pathogenesis. Here, a novel self-assembling human cardioid differentiation protocol was used. Initially, three concentrations of a canonical Wnt pathway activator were tested, and addition of ascorbic acid. A higher concentration led to a full loss of organoids, while ascorbic acid slightly increased the number of organoids discarded but increased the number of beating control-derived organoids. Lastly, with hiPSCs established from LVNC patients, and a healthy relative, three initial seeding densities were tested. We experienced a high degree of heterogeneity in size and morphology, vascularisation formation, number of beating and discarded cardioids. We also analysed organoid circularity at two different stages of differentiation, but no conclusions can be made due to result variability and inconsistency between both cell lines, and/in all seeding conditions presenting no clear pattern. We also experienced a lack of fluorescence signal or a low antibody penetrability after immunofluorescence staining, and increased all incubation periods but still experienced a lack of signal for cardiomyocytes. Then, due to organoid size and density, we observed a low reachable sample depth during fluorescence microscopy. An additional step of ScaleA2 optical clearing was tested, which showed that a 10 day incubation period is crucial for imaging quality and reachable depth improvement. In conclusion, this is a promising but very demanding protocol that has to be thoroughly followed, with many influencing factors. More work is still necessary to improve its efficiency for further studies to determine their cardiac development capacity, and if it can be used to model LVNC in the future.
- The role of diversification in achieving a sustainable competitive advantage: a case study of googlePublication . Ereojikwe, Adaeze; Pedro, IldaThis thesis uses Google as a case study to examine how diversification contributes to a sustained competitive advantage. The importance of diversification strategies for businesses looking to grow sustainably and withstand market competition is becoming more widely acknowledged. This study looks at how Google has used its resources and core strengths to gain a sustained competitive advantage across a variety of companies, through a review of the company's diversification initiatives. Drawing on theoretical frameworks such as the Resource-Based View (RBV) and Dynamic Capabilities Model, this study examines how Google's effective utilization of its resources and core competencies, alongside its ability to adapt to the dynamic conditions of the market, have allowed for effective diversification. Indicators of sustainable competitive advantage, like market share, brand strength, and customer loyalty, are compared to Google's financial performance metrics in this thesis using approaches that include financial analysis, case study, and surveys. Through an examination of Google's diversification initiatives in a number of industry sectors, the study offers insights into how well diversification strategies work to drive long-term value creation. The results demonstrate how Google has maintained a competitive edge in fast-moving and cutthroat sectors because to its diverse portfolio, which is supported by its core skills. In order to gain a sustained competitive advantage, the study emphasizes how crucial it is to match diversification programs with organizational strengths, market possibilities, and strategic objectives. In addition to providing useful implications for businesses looking to improve their competitive position through diversity, the research also advances academic knowledge of diversification strategies.
- Projeto EdUAlg - a editora da Universidade do Algarve - imprimindo o seu legadoPublication . Gateira, Márcia Helena; Caravela, Gabriela Borges Martins; Encarnação, Dionilde Sarita G. CamachoEste projeto de investigação aplicada visa agregar valor à Universidade do Algarve Editora através da criação e do desenvolvimento de um plano de comunicação estratégica que envolve três importantes ferramentas: identidade visual, brand personality e presença digital. O foco é criar uma relação próxima e afetiva entre a editora acadêmica e o seu público, buscando alcançar benefícios para toda a comunidade. Contudo, para que isso aconteça, primeiro é necessário tornar a editora reconhecida e acolhida pela população acadêmica – o seu público-alvo. Assim, surge a ideia da criação do nome EdUAlg e de uma marca gráfica, como forma de afirmar a personalidade da editora acadêmica e reforçar a sua identidade. A metodologia utilizada foi realizada através do estudo de duas editoras acadêmicas de referência, a Editora da Universidade do Estado do Rio de Janeiro (Brasil) e a Imprensa da Universidade de Coimbra (Portugal), onde foram recolhidos dados primários e secundários. E também através de um inquérito realizado na Universidade do Algarve para avaliar a forma como a editora se comunica com a comunidade acadêmica. O resultado almejado é explorar o potencial do segmento editorial existente na instituição desde 2017. Um objetivo que pode ser alcançado com a contribuição deste estudo, como primeiro passo. Espera-se assim que a Universidade do Algarve Editora se desenvolva, transformando-se em uma editora acadêmica reconhecida dentro e fora da universidade.
- Characterization of TYK2 role in IL-7/IL-7R signaling in T-cell Acute Lymphoblastic LeukemiaPublication . Cavaco, Joana Margarida Bartolomeu; Fragoso, Ana Rita; Tavares, ÁlvaroA leucemia linfoblástica aguda (LLA) é uma neoplasia hematológica que pode ser subdividida de acordo com o tipo de linfócitos afetados. Assim sendo, denomina-se leucemia linfoblástica aguda de células T (LLA-T), quando existe a expansão e proliferação de linfócitos T imaturos, e leucemia linfoblástica aguda de células B (LLA-B), quando associada à proliferação de linfócitos B imaturos. A LLA é o cancro pediátrico mais comum, sendo que dentro destes casos, aproximadamente 15% são de LLA-T. Após tratamento, 85% das crianças com LLA-T atingem remissão. No entanto, nos adultos esta percentagem é mais reduzida, ficando entre os 20-40%. O tratamento da LLA-T consiste num programa intenso de quimioterapia, que está associado a vários efeitos secundários. Para além disso, apesar destes doentes terem um prognóstico favorável à data do diagnóstico, a taxa de recidiva é elevada e está associada a um pior prognóstico, uma vez que a doença persistente é geralmente resistente à quimioterapia. Como tal, os efeitos secundários associados à quimioterapia e a falta de tratamento alternativos após recidiva realça a necessidade urgente da descoberta de novas abordagens terapêuticas. Este tipo de leucemia (LLA-T) está associada a diversas alterações genéticas, que resultam na desregulação do processo de desenvolvimento de células T, e por sua vez, levam à proliferação não controlada de células imaturas. A via de sinalização da interleucina-7 (IL-7) desempenha um papel muito importante no processo de diferenciação das células T. Estudos realizados demonstram que a eliminação desta via resulta no bloqueio do desenvolvimento de linfócitos T e B, e consequentemente na produção de linfócitos T não funcionais e numa população de linfócitos B reduzida. A ativação desta via requer a participação da IL-7 e do seu recetor, o IL-7R. O recetor da IL-7 é composto por duas subunidades, nomeadamente a cadeia a (IL-7Ra) e a cadeia g comum. Estas subunidades não possuem atividade catalítica intrínseca e como tal, para poderem fosforilar substratos e darem início à transdução de sinal necessitam da ação de outras proteínas, como as cinases Janus (JAK) JAK1 e JAK3, que se ligam à cadeia IL-7Ra e à cadeia g comum, respetivamente. Quando a interleucina se liga ao recetor, JAK1 e JAK3 fosforilam-se mutuamente, causando a sua ativação, o que resulta na fosforilação de tirosinas presentes nas cadeias do recetor, criando locais de ancoragem para a proteína STAT5. Esta proteína, ao ser ativada por JAK1 e JAK3, sofre dimerização e é transportada para o núcleo onde, atuando como um fator de transcrição, dá início à transcrição de genes envolvidos na proliferação, diferenciação e apoptose. (...)
- Towards controlling the reproductive cycle of azooxanthellate gorgonians in cultivation: diet and environmental driversPublication . Filipe, Joana; Engelen, Aschwin; Coelho, MárcioThe present study compared the feeding preferences and reproduction of two species of gorgonian corals, Paramuricea grayi (Johnson, 1861) and Eunicella verrucosa (Pallas, 1766). The research objectives were to assess different feeding responses these two species, had when given different types of food, and when the feed was given additional treatments (adding yeast, blending, or both). Daily observations of the proportion of open polyps and mucus production were conducted, before, during, and after the feeding periods. Additionally, each feeding period was recorded, to analyse polyp behaviour. The second objective was to differentiate the reproductive strategies of the two species (spawning periods and gonad development), and better understand their reproductive cycle. This was done by regularly sampling fragments and analysing the gonads of different colonies. Results showed that feeding was better with live food. Additionally, frozen red plankton was the least ingested type of food used. When comparing the two species they showed overall similar feeding rates, except when live food was used, in which case, E. verrucosa showed a higher feeding rate. The different treatments showed little positive effects on the feeding rate of P. grayi. However, the same was not observed for E. verrucosa, with improved feeding rates when yeast was added to rotifers and cyclops, and slightly with copepods. Furthermore, both species developed mature gonads throughout this study. Interspecific differentiation was detected in spawning periods, while P. grayi possibly spawned at the beginning of August, E. verrucosa predicted spawning was at the end of August, and at the beginning of September. In conclusion, this study provides valuable insights into the feeding preferences and reproductive strategies of two coral species of gorgonians, kept at Oceanário de Lisboa. The results highlight the importance of considering species-specific differences in coral biology and ecology when maintaining these species in aquariums.
- Development of novel nanoplatforms for the imaging and targeting of breast tumour microenvironmentPublication . Pereira, Mariana Franco; Maia, Ana Teresa; Mendes, BárbaraBreast cancer is the most diagnosed neoplasia in the world and affects millions of women each year. Despite being the type of cancer with the greatest selectivity of treatments, these lead to a wide range of side effects. Gene therapy has emerged as a new therapeutic approach for the treatment of various diseases. This therapy involves transferring genes or regulatory sequences into target cells. This can modify or inhibit the gene expression, improving the treatment of hereditary or acquired diseases. In this work polymeric nanoparticles were developed due to their excellent properties, including the ability to protect genetic material from degradation by nuclease, low toxicity, biocompatibility, biodegradability, and high stability. Polyplexes were produced and characterized as a subclass of polymeric nanoparticles, regarding their physicochemical properties (size, polydispersity index and surface charge), cell viability and transfection efficiency in 2D and 3D cell cultures. Polyplexes when complexed with nucleic acids (pDNA and pDNA-miR-125b) had a small size and positive surface charge at N/P ratio of 20. Regarding complexation with miR-125b, there is the formation of large nanoparticles in the same ratio. The cell viability analysis showed that the polyplexes were not toxic. Transfection assays demonstrated that polyplexes are more efficient at delivering miR-125b to BC cells in 2D. Transfection efficiency was highest in the MDA-MB-231 cells with 88% of transfection. The results of the expression of miR-125b showed a transient increase in its expression levels, contributing to the inhibition of proliferation and cell migration of BC cells. The results of the incubation of the polyplexes in the breast cancer spheroids showed low transfection efficiency, which can be related to the morphology of the spheroids. In conclusion, the S2 polyplexes proved to be an excellent nanoparticle for delivering miR-125b in breast cancer cells, representing a new potential therapeutic agent. Future testing on 3D spheroid models can include using PAMAM nanoparticles as the delivery system or improving the functionalization of S2 polyplexes to increase transfection efficiency and, consequently, the expression levels of miR-125b.