Effects of glycation by methylglyoxal in saccharomyces cerevisae

Mestrado em Bioquímica (Bioquímica Médica) Universidade de Lisboa; Faculdade de Ciências, 2021Glycation is the nonenzymatic modification of biomolecules caused by reactive dicarbonyl species. In vivo, the major physiological glycation agent is methylglyoxal. This compound’s formation occurs in all living cells, mainly nonenzymatically from dihydroxyacetone phosphate and D-glyceraldehyde 3-phosphate during glycolysis. When glycation occurs on proteins it originates advanced glycation end-products (AGEs), which will change the structure and stability of proteins, consequently impairing their functionality. AGEs tend to accumulate on cells, being associated with ageing and several human diseases, such as diabetes and amyloidotic neuropathies (Alzheimer’s disease, Parkinson’s disease and transthyretin amyloidosis). Hence, there is a growing interest in this post-translational modification. However, little is known about the physiologic effects of glycation, since most studies use in vitro approaches, which do not fully reproduce the in vivo process. Saccharomyces cerevisiae is an ideal model of in vivo glycation, being able to reproduce the effects that happen in higher eukaryotic cells. The in vivo study and use of Saccharomyces cerevisiae cells with different genetic backgrounds, gives us an accurate vision of a wide range of phenotypical and physiological effects caused by glycation. In the present study we show that the glyoxalase system seems to be the major detoxifying mechanism of methylglyoxal, since mutations on this pathway lead to lower growth rates. Moreover, using fluorescence microscopy and flow cytometry we found that glycation is not sufficient to alter cell morphology or its viability. However, the effects of glycation seem to be devastating on mitochondrial activity causing its dysfunction and the accumulation of reactive oxygen species (ROS). These findings provide insight to uncover knowledge of the process of glycation, necessary for better comprehension and advance in the cure and early identification of many human diseases that haunt our society

Distance educational relationship and senses of belonging: the voices of students

In a viral society in which the social being claims the ability to maintain distance and the socially desirable representation of the body, in particular the face, claims its concealment, the distance educational relationship represents a critical area that deserves to be highlighted in the research agendas. This study aims to explore the sense of belonging of 98 students who attend a distance learning university. For this purpose, an open-ended questionnaire was applied, previously disclosed in closed groups on social networks. The students' sense of belonging was analysed through the types of connections they maintain with the campus, course, peers and teachers. The analysis of the narratives expresses a great diversity, density of experiences and expectations in the connections and senses of belonging. Attributing great importance to teachers in the appropriation of knowledge, it is essentially with their peers - other students - that the connections and sense of belonging acquire greater expressioninfo:eu-repo/semantics/publishedVersio

Promoção da igualdade de género em jovens institucionalizados: um projeto educativo

Neste trabalho a promoção da igualdade de género assume-se como área central para a qual pretendemos dar um pequeno contributo. Pretendemos promover a reflexão sobre como os estereótipos de género influenciam a vida dos homens e mulheres, averiguar os comportamentos de igualdade, desmistificar alguns estereótipos, e refletir e identificar ações/comportamentos promotores de igualdade no quotidiano dos jovens. Neste sentido, elaborámos um projeto educativo que foi aplicado junto de jovens do sexo masculino, com idades compreendidas entre os 16 e os 18 anos, institucionalizados num Lar de Infância e Juventude, do distrito de Bragança. Inicialmente aplicamos um questionário de avaliação de necessidades junto dos jovens. Após a aplicação deste questionário realizamos um plano formativo, com o objetivo de dar resposta a essas necessidades, planificamos seis sessões de temas variados, como violência doméstica, profissões e papel do homem e da mulher em casa, na família e no trabalho. No fim, voltamos a aplicar um questionário semelhante ao inicial, para podermos comparar os resultados e concluir quais foram as mudanças ocorridas. No que concerne às principais conclusões do nosso projeto, parece-nos importante realçar que os jovens estão muito bem instruídos no que toca às divisões de tarefas e principais funções parentais. No entanto, parece-nos importante realçar que existem alguns aspetos que mereciam atenção dos educadores dos jovens, relativamente ao que diz respeito a escolhas profissionais, aspeto que se reveste de grande importância visto que os jovens estão numa fase de escolherem as carreiras profissionais.In this work, the promotion of gender equality is a central area for which we intend to make a small contribution. We intend to promote the reflection on how gender stereotypes influence the lives of men and women, to investigate equality behaviors, to demystify some stereotypes, and to reflect and identify actions / behaviors that promote equality in the daily lives of young people. In this sense, we developed an educational project that was applied to young men, aged between 16 and 18, institutionalized in a Home for Children and Young people, in the district of Bragança. Initially we applied a questionnaire to assess the needs of young people. After the application of this questionnaire we carried out a training plan with the objective of responding to these needs. We planned six training sessions on topics such as domestic violence, professions and the role of men and women at home, family and work. At the end we returned to apply the same questionnaire as the initial one, so we could compare the results and conclude what the changes were. With regard to the main conclusions of our project, it seems important to emphasize that young people are very well educated in the division of tasks and main parental roles. However, to us it seems important to emphasize that there are some aspects that deserve the attention of educators of young people, as far as professional choices are concerned, which is very important as young people are in a stage of choosing their professional careers

Avaliação da capacidade de formação de biofilme por organismos da microbiota oral e do potencial antimicrobiano de óleos essenciais

Tese de mestrado em Microbiologia Aplicada, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, em 2018A microbiota oral é constituída por uma comunidade microbiana muito diversa incluindo espécies de bactérias pertencentes a Enterococcus, Streptococcus e Actinomyces. Estas bactérias, são conhecidas por formarem comunidades dinâmicas de células sésseis que interagem e aderem irreversivelmente a um substrato sólido e umas às outras. Ao mesmo tempo, uma construção de substâncias extracelulares poliméricas (SEP) vão embeber e proteger as estirpes produtoras, conferindo proteção contra agentes exteriores. Estes biofilmes são uma grave questão de saúde pública devido à sua contribuição para infeções e eventual falha terapêutica, bem como por facilitarem as trocas genéticas entre as diferentes bactérias. Nos dias de hoje, os compostos naturais, como os óleos essenciais -OEs-, estão a ser estudados como alternativas para penetrarem no biofilme e eliminarem as bactérias presentes, contribuindo para a erradicação destas estruturas. Os OEs são metabolitos secundários produzidos por plantas cada vez mais utilizados como agentes antimicrobianos; os OEs de cravo, oregão e tomilho estão entre os mais promissores. Este trabalho teve como objetivo avaliar bactérias presentes na microbiota oral na respetiva capacidade de produzir biofilmes, em culturas puras e mistas. Foram testadas diferentes condições experimentais (composição do meio, diferentes temperaturas e diferentes tempos de incubação). Os resultados mostraram que o meio Brain Heart Infusion suplementado com mucsina (uma simulação in vitro do ambiente oral), 48 h de incubação à temperatura ambiente favoreceram a formação de biofilme em culturas puras e polimicrobianas. Posteriormente, fez-se um screening dos OEs de cravo, oregão e tomilho procurando avaliar a sua capacidade de controlar o crescimento bacteriano. Os ensaios usando o método da microdiluição permitiram a determinação da concentração mínima inibitória (CMI), concentração mínima bactericida (CMB) e concentração mínima de erradicação de biofilme (CMEB). Os OEs do cravo e tomilho mostraram os resultados mais promissores podendo ser considerados boas alternativas antimicrobianas. Para confirmar esta afirmação foi desenvolvido um modelo de “escova-de-dentes”. Para simular uma escova-de-dentes contaminada com microrganismos, foram inoculadas fibras de nylon com as bactérias orais em estudo. Após a formação de biofilme, foram testados os óleos essenciais de tomilho, de óregão e de cravo a diferentes concentrações na capacidade de provocar a disrupção da matriz e eliminar as bactérias. Os resultados demonstraram o potencial antimicrobiano dos óleos essenciais de tomilho e de cravo confirmando a possibilidade da utilização destes compostos naturais como alternativas válidas aos desinfetantes tradicionais e outros agentes antimicrobianos até agora utilizados na microbiota oral.Oral microbiota is composed by Enterococcus, Streptococcus and Actinomyces, among other microrganisms. These bacteria are known for forming dynamic communities of sessile cells, interact and adhere irreversibly to solid surfaces and each other. Concurrently, the construction of extracellular polymeric substances (EPS) will cover and protect the producing strains, conferring protection against exterior agents. These biofilms are a major public health concern due to their contribution to infection and therapeutical failure, as well as for facilitating genetic exchanges. Nowadays, natural compounds, such as essential oils -EOs-, are being analysed as alternatives to penetrate the biofilm and eliminate the bacteria present, contributing to the eradication of these structures. EOs are secondary metabolites produced by plants increasingly used as antimicrobial agents; clove, oregano and thyme EOs being among the most promising products. The present work aimed to evaluate bacteria present in the oral microbiota for their capacity to produce biofilms, both in pure and mixed cultures. Distinct growth media, temperatures and times of incubation were tested. Results showed that Brain Heart Infusion medium supplemented with mucin (an in vitro simulation of the oral environment), 48h of incubation and room temperature favoured biofilm formation for pure and polymicrobial bacterial cultures. Subsequently, clove, oregano and thyme EOs for screened for their capacity to control the growth and/or eliminate the oral bacteria. Assays using the microdilution methodology allowed the determination of Minimum Inhibitory Concentrations (MIC), Minimum Bactericidal Concentrations (MBC) and Minimum Biofilm Eradicating Concentrations (MBEC). Clove and thyme showed the most promising results and can be considered good antimicrobial alternatives. To further confirm such an assumption a toothbrush-model was developed. To simulate a toothbrush contaminated with microorganisms, as usually occurs in a common bathroom, sterilized nylon fibers inoculated with the oral bacteria under study were used. After allowing biofilm formation, essential oils at different concentrations were tested for their ability of disrupt the matrix and eliminate the bacteria. Results demonstrated the antimicrobial potential of thyme and clove essential oils, as occurred in the screening assays. Thus, the present study verified that EOs can be considered to be valid alternatives to traditional disinfectants and other antimicrobial agents

Crescimento de Chlorella Vulgaris (chlorophyta unicelular) na presença de compostos fenólicos

Neste trabalho avaliou-se o efeito de diferentes tipos de extractos da planta de rosmaninho (Rosmarinus officinalis) ricos em compostos fenólicos, no crescimento e na fisiologia da microalga Chlorella vulgaris. Os extractos foram obtidos por infusão aquosa a quente e a frio, esta ultima com dois períodos de extração (5 e 21 dias). Os ensaios foram desenvolvidos em culturas batch com extratos à concentração de 10%, 25% e 30% (v/v). Os resultados mostraram para os extractos a frio que o crescimento da microalga foi afetado apenas com extratos de 21 dias, levando ao aumento da taxa específica de crescimento (μ) e da densidade celular, bem como da concentração de clorofila a (Chl a) e do teor em proteinas, numa relação direta com a concentração de extrato testada. A exposição aos extractos a quente apesar de levar ao aumento de µ e da densidade celular final de C. vulgaris, concomitantemente induziu alguma toxicidade a nível fisiológico, visível pela diminuição dos teores de Chl a e proteínas. Os compostos fenólicos identificados por HPLC, nestes dois tipos de extratos, mostraram diferenças qualitativas e quantitativas. O extrato a frio apresentou essencialmente ácido rosmarínico e quercetina, enquanto que no extrato a quente foram quantificados sete compostos distintos, sendo os mais abundantes os ácidos rosmarínico e gálico. Considerando o perfil de compostos fenólicos encontrado, é possível concluir que o grau de inibição/estimulo do crescimento de C. vulgaris está relacionado com a concentração e composição em compostos fenólicos dos extractos estudados.In the present research the effect of different types of plant extracts of rosemary (Rosmarinus officinalis) rich in phenolic compounds was evaluated on the growth and physiology of microalgae Chlorella vulgaris. The aqueous extracts were obtained by infusion in cold and hot extraction process, this last with two periods (5 and 21 days). The tests were conducted in batch cultures with the extracts concentration of 10%, 25% and 30% (v / v). Concerning the cold extracts, results showed that the growth of microalgae was affected only by 21 days extracts, leading to increased specific growth rate (μ) and cell density, as well as chlorophyll a (Chl a) and proteins concentrations, in a direct relationship with the concentration of extract tested. The exposure to hot extracts, despite an increase μ and final cell density of C. vulgaris, concomitantly induced also some physiological ltoxicity, perceptible by a decrease of Chl a and proteins content. Phenolic compounds identified by HPLC, in these two types of extracts, showed quantitative and qualitative differences. The rosemary cold extract is mainly composed by rosmarinic acid and quercetin, whereas in hot extract seven different compounds were quantified, the most abundant being the rosmarinic and gallic acids. Regarding to the profile of phenolic compounds founded, it seemed that the degree of inhibition/stimulation of microalgae growth of C. vulgaris is related to the concentration and composition of phenolic compounds of the extracts studied.El presente estudio evaluó el efecto de diferentes tipos de extractos de plantas de romero (Rosmarinus officinalis) ricos en compuestos fenólicos, sobre el crecimiento y fisiología de la microalga Chlorella vulgaris. Los extractos acuosos se obtuvieron mediante la infusión caliente y frío, esta última extracción con dos períodos (5 y 21 días). Los ensayos se realizaron en cultivos discontinuos con la concentración de extractos de 10%, 25% y 30% (v / v). Los resultados para los extractos fríos mostraron que el crecimiento de las microalgas se vio afectado sólo para los extractos con 21 días, conducente a lo aumento de la tasa específica de crecimiento (μ) y de la densidad de las células, bien como la concentración de clorofila a (Chl a) y el contenido de proteínas, en una relación directa con la concentración de extracto de ensayo. La exposición a los extractos en caliente, si bien han conducido a un aumento de μ y de la densidad final de células de C. vulgaris, concomitantemente han indujo cierta toxicidad a nivel fisiológico, visible por una disminución de contenido en Chl a y proteínas. Los compuestos fenólicos identificados por HPLC, en estos dos tipos de extractos, mostraron diferencias cuantitativas y cualitativas. El extracto en frío presentó esencialmente el ácido rosmarínico y la quercetina, mientras que el extracto en caliente presentó siete compuestos distintos, los más abundantes siendo el ácido rosmarínico y el ácido gálico. Teniendo en cuenta el perfil de los compuestos fenólicos encontrado, es posible concluir que el grado de inhibición/estimulación del crecimiento de C. vulgaris está relacionado con la concentración y composición de compuestos fenólicos de los extractos estudiados.info:eu-repo/semantics/publishedVersio

Vinificação de uvas afectadas por podridão ácida

Mestrado em Engenharia Alimentar - Qualidade e Segurança Alimentar - Instituto Superior de AgronomiaIn this study we evaluated the use of grapes with sour rot on the wine fermentation and the consequent final quality of wine. For that, microvinification of healthy grapes belonging to the variety of Trincadeira Preta and Cabernet Sauvignon were performed to which were added grapes affected by sour rot. The musts and wines, corresponding to 30 and 50% (w/w) of rotten grapes, showed an increase in the parameters color intensity, total anthocyanins and total phenols in function to the proportion of rotten grapes. This increase also reflected in a higher sugar concentration of grape must and therefore an increase in the alcohol content of wines produced. The higher volatile acidity in wines made from rotten grapes was due to its higher initial content in musts. It was possible to stabilize microbiologically wines with sour rot in order to avoid introducing potentially harmful microorganisms, although they possessed higher levels of residual sugars. The results of sensory evaluation by an untrained panel, before malolactic fermentation and after six months of probation, showed no statistically significant differences exist between different types of wines. In conclusion, it was possible to vinify grapes with high levels of sour rot without the quality of the wines being distinctly affected by the tasting panel

Dataset from 55 experts engaged in nature conservation in Mozambique

Data ArticleThe data of this article is related to the original article entitled “An expert-based approach to assess the potential for local people engagement in nature conservation: The case study of the Niassa National Reserve in Mozambique” [1], published in Journal for Nature Conservation. The dataset is from an online and selfadministrated survey with 55 experts aware of conservation policies and incentives under implementation in the Niassa National Reserve (NNR), the largest protected area in the country and thirdlargest in Africa. The survey included four sections of both compulsory and non-compulsory questions, mostly in closedended Likert-scale. In the first section, experts were asked about the main practices that threaten biodiversity conservation in the NNR, the actors who are directly and indirectly responsible for each practice, and the reasons for local people's involvement with those practices. The second section was about the effectiveness and limitations of the current compensation measures to engage local residents with conservation-friendly practices. In the third section, respondents were asked to select new measures to enhance the current conservation status and engage local people more effectively in conservation. The last section was about the socio-economic profile of respondents. The survey was conducted from June to September 2017. The paper includes the survey itself, raw data in an Excel spreadsheet, descriptive analysis, crosstabulation and Post Hoc cellwise tests (goodness of fit). Data are provided for public use and can serve as a benchmark for collaboration in order to conduct more comprehensive research, comparative analysis as well as panel data can be derived. This data can also have applications in other fields such as mathematics, statistics, and computationinfo:eu-repo/semantics/publishedVersio

Politica 2.0. : a atividade dos partidos políticos nas redes sociais

Mestrado em Marketingevolução da comunicação política tem acompanhado o desenvolvimento das novas tecnologias de informação e comunicação ao longo dos tempos, adotando um modelo baseado no Marketing. Com o surgimento da Internet os políticos/ partidos compreenderam as vantagens da utilização deste novo meio de comunicação. Nos últimos anos, a Internet sofreu uma mudança de paradigma, dando origem à chamada Web 2.0, caracterizada, parcialmente, pelos Social Media. Com o objetivo de criar relacionamento com os cidadãos, os partidos políticos iniciaram um novo tipo de comunicação, tendo por base as ferramentas da Web 2.0, originando a Política 2.0, fundamentada no Marketing Digital. O objetivo do presente estudo é a avaliação do desempenho dos partidos políticos Portugueses em termos de interatividade e envolvimento com os fãs no Facebook, comparando-os com outros partidos políticos de diferentes Países. Para atingir este objetivo realizou-se um estudo quantitativo tendo por base dados recolhidos das plataformas de Facebook dos cinco partidos políticos com maior representação nos sistemas democráticos, de Portugal e de outros quatro Países. A análise dos resultados observados entre diferentes Países foi avaliada através do teste ANOVA. Os resultados obtidos relativamente à interatividade gerada nas plataformas de Facebook dos partidos políticos são distintos entre diferentes Países, enquanto que em termos de envolvimento não é possível diferenciar as plataformas geridas por partidos políticos de diferentes nações. Este estudo contribui com uma visão quantitativa do desempenho dos partidos políticos Portugueses no Facebook, contribuindo com informação relevante para investigações futuras no âmbito da interatividade e envolvimento gerados nesta plataforma digital.The evolution of political communication has kept up with the development of new information and communication technologies throughout time, assuming a Marketing-based model. With the advent of Internet Politicians/Political Parties understood the advantages of using these media. Recently, Internet has undergone a paradigm shift, giving rise to Web 2.0, which is characterized, partially, by the Social Media. With the goal of developing a relationship with citizens, Political Parties started a new type of communication, using the tools available on the Web 2.0 creating Politics 2.0, based on Digital Marketing. The objective of this study is to evaluate the performance of Portuguese Political Parties in terms of interactivity and engagement with their fans on Facebook, comparing them with Political Parties of other countries. To achieve this goal a quantitative study was conducted considering data retrieved from the Facebook sites of the five most represented Political Parties of the Portuguese democratic system, as well as of four other countries. The results obtained from different countries were analysed through the ANOVA test. The results regarding the interactivity generated in the Facebook sites of the Political Parties are different between distinct countries, however, in terms of engagement it is not possible to distinguish the Political Parties' Facebook platforms from different countries. This study contributes with a quantitative point of view of the performance on Facebook, by the Portuguese Political Parties, as well as with relevant information for future research on the field of interactivity and engagement generated on this digital platform