Comparação de métodos para identificação de bactérias filamentosas responsáveis pelo fenómeno de bulking numa ETAR

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do Grau de Mestre em Engenharia do Ambiente – Perfil Engenharia SanitáriaNo tratamento secundário de águas residuais, o processo de lamas activadas é o actualmente mais utilizado. Este tratamento assenta no crescimento de bactérias formadoras de flocos que se separam por gravidade do sobrenadante clarificado, sendo indispensável para este processo uma boa floculação consequência de um crescimento equilibrado entre estas bactérias e as bactérias filamentosas. Quando existe um crescimento excessivo destas últimas verifica-se um fenómeno indesejado designado de bulking filamentoso. O presente trabalho teve como principal objectivo a comparação de diferentes métodos para identificação de bactérias filamentosas de uma ETAR com um sistema de tratamento de lamas activadas, nomeadamente através de uma observação microscópica clássica (amostra bruta e amostra corada) utilizando colorações de Gram, de hematoxilina e eosina e aplicação dos métodos API e MALDI-TOF. Através da observação microscópica das amostras coradas com hematoxilina e eosina foi possível verificar que estavam presentes pelo menos dois tipos de microrganismos. Obtiveram-se igualmente os mesmos resultados com a aplicação da coloração de Gram, tendo os microrganismos presentes sido classificados de Gram negativos. Relativamente à aplicação do kit API 20 E, foram identificados os géneros Serratia e Enterobacter. No entanto, não foi possível obter a identificação ao nível da espécie predominante na amostra. Através da aplicação do método MALDI-TOF-MS, tornou-se possível a identificação de proteínas correspondentes ao género Serratia sp., género Enterobacter sp., espécie Peptostreptococcus anaerobius, género Geobacter sp., espécie Escherichia coli e espécie Syntrophus aciditrophicus. A principal razão para não ter sido possível uma identificação ao nível da espécie do microrganismo filamentoso predominante esteve relacionada com o facto de não ter sido possível obter uma amostra pura dentro do tempo da realização das experiências. Possivelmente, o meio de cultura escolhido não foi suficientemente selectivo potenciando o crescimento de outras espécies presentes. Relativamente aos métodos testados concluiu-se que através da observação microscópica utilizando colorações de Gram e hematoxilina e eosina, são fáceis e rápidos de aplicar podendo ser utilizados na identificação rotineira dos organismos presentes numa ETAR

The Role of Endocrine-Disrupting Chemicals in Male Fertility Decline

Endocrine-disrupting chemicals (EDCs) are exogenous compounds with natural or anthropogenic origin omnipresent in the environment. These compounds disrupt endocrine function through interaction with hormone receptor or alteration of hormone synthesis. Humans are environmentally exposed to EDCs through the air, water, food and occupation. During the last decades, there has been a concern that exposure to EDCs may contribute to an impairment of human reproductive function. EDCs affect male fertility at multiple levels, from sperm production and quality to the morphology and histology of the male reproductive system. It has been proposed that exposure to EDCs may contribute to an impairment of sperm motility, concentration, volume and morphology and an increase in the sperm DNA damage. Moreover, EDCs exert reproductive toxicity inducing structural damage on the testis vasculature and blood-testis barrier and cytotoxicity on Sertoli and Leydig cells. This chapter will explore the effects of EDCs in male reproductive system and in the decline of male fertility

The LMOOC4SLAV Project: Academic Discourse for Academic Mobility

studies in another country using a second language (L2) they know with a proficiency level B1/B2. A path to facilitate a successful mobility exchange, as well as students' inclusion in a multicultural and multilingual environment through innovative learning and teaching practices offering educational models to modernize and internationalize the higher education system, and to place European training experiences on the global training scene through Massive Open Online Courses (MOOCs) are some of the main priorities of the LMOOC4Slav - Romance Languages for Slavic-speaking University Students, an Erasmus+ funded project (2021-1-IT02-KA220-HED-000027501). Although not exclusively, its primary target audience consists of university students, mainly with Slavic languages as their mother tongue (L1), learning Romance languages, specifically Italian and Portuguese, who intend to do a mobility period at a university in Portugal or Italy, and also native Slavicspeaking teachers who teach Portuguese and Italian as L2 to those students. The project centres around the production of two Language MOOCS (LMOOCs), one for Italian and the other for Portuguese, organised in six modules. The aim is to promote students' development of linguistic fluency in academic contexts and access to authentic academic situations and learning tools to enhance their ability to learn how to learn. It also focuses on developing a repertoire of Open Educational Resources (OERs) intended for Slavic language teachers and students of Portuguese and Italian as L2. These resources will allow their reuse in different learning environments, guided by an online pedagogical guide for integrating LMOOCs and OERs. The project outputs will remain available in an open-source repository after its end ensuring its sustainability

Osmotic dehydration: an emerging technology applied to the fruit and vegetable sector

Apresentação em painelThe current unsustainable production and consumption patterns are one of the drivers for Bioeconomy strategy implementation. The horticultural industry produces quantities of by-products and waste whose valorisation, through innovation, enhances new products and production processes development. The aim of this work was to develop new dehydrated food products from horticultural by-products, pumpkin, and courgette, using osmotic dehydration (DO) technology by immersing the food in an osmotic solution (OS).info:eu-repo/semantics/publishedVersionhttps://www.insa.min-saude.pt/wp-content/uploads/2022/11/ICFNH22_Bookofabstracts.pd

Microaerophilic growth characteristics of Pseudomonas aeruginosa importance to the successful treatment of chronic infections in cystic fibrosis lungs

Patients with CF lung disease are susceptible to chronic infections by various pathogens, such as Pseudomonas aeruginosa. This pathogen is able to adaptat to the environment in CF lungs, characterized by inflammatory defences, oxygen restriction, and poor nutrient availability. It is well established that, once P. aeruginosa infection is installed in the lungs, it is almost impossible to eradicate, due to sophisticated genotypic and phenotypic adaptation mechanisms that develop according to the stage of infection. Understanding those changes and the identification of specific characteristics that allow P. aeruginosa eradication before the onset of chronic infection is urgent. In this work, P. aeruginosa adaptation under microaerophilic and anaerobic conditions was assessed in terms of phenotypic charatceristics, antibiotic susceptibility and expression of antibiotic resistance mechanisms (mexAB operon). Results showed, when compared with aerobic conditions, similar growth and emergence of intermediate resistance profiles for ciprofloxacin and imipenem, but no significant variation in operon mexAB expression. It was also observed an increase of colony morphotypes with the decrease of oxygen availability, mainly in 5% O2. Nevertheless oxygen depletion has no significant effect on P. aeruginosa growth and mexAB expression, affecting, however, the phenotypic characteristics and antibiotic susceptibility profiles. Despite the overall observations, the microaerophilic environment with 5% O2, seems to demonstrate a transient distinct behaviourwhich can be a point of evolution into chronic infection and as such a possible treatment target

Adapting to survive: how Candida spp. respond to environmental physiological constraints

Candida species are important human pathogens and have emerged as a leading cause of nosocomial fungal infections. In order to survive and proliferate within the human host, these species have to adapt to the different niches and assimilate the available nutrients. For instance, during infection, they can encounter glucose-poor microenvironments and some studies have suggested that the ability to use non-fermentable carbon sources affects the virulence of these pathogens. Our studies have demonstrated that the presence of alternative carbon sources such as lactate and acetate influence Candida biofilm formation, antifungal drug resistance and immune recognition. Additionally, there is evidence that carboxylate transporters have a role on these processes. An overview of the most significant results will be presented.Our data support the view that the different carbon sources present in the host niches affect directly the physiology of Candida cells, with implications on how these pathogens respond to antifungal treatment

Aging effect on functionalized silver-based nanocoating braided coronary stents

A previously developed fiber-based polyester (PES) stent, with mechanical properties comparable to commercial nitinol stents, was coated with metallic silver (Ag0) and silver oxides (AgxO) thin films through direct current (DC) magnetron sputtering. Ag0 and AgxO coatings provide antimicrobial properties to the stents to minimize the occurrence of coronary stent infections. Nevertheless, the stent interacts with the atmosphere and then with the biological fluids and may lead to the generation of silver species with diminished antimicrobial efficiency and/or prone to induce cytotoxicity. Therefore, stent coating nanostructures aged 3 months were thoroughly analyzed by X-ray photoelectron spectroscopy (XPS) and their antimicrobial and cytotoxicity properties were assessed. Aging led to the presence of silver carbonate and bicarbonate as well as chemisorbed oxygen species in Ag0 and AgxO coatings. Bactericidal efficacy was tested against an important nosocomial bacterium, particularly associated to indwelling devices: Staphylococcus epidermidis. Aged Ag0 and AgxO coating presented a Log reduction of 1 and 2 at their surface; respectively. However, aged stents were able to induce a Log reduction of 2 (Ag0) and 4 (AgxO) on the surrounding medium. Only aged AgxO stent was able to provide a mild reduction of the bacterium at its surface and a clear antimicrobial effect (Log reduction >3) within its vicinity. More importantly, both aged Ag0 and AgxO stents were shown to be compatible with fibroblasts cells indicating that they can be safely used as indwelling devices, despite the aging effectThis work was funded by FEDER funds through the Operational Competitiveness ProgramCOMPETE and by National Funds through Fundacao para a Ciencia e Tecnologia (FCT)-under the projects PTDC/CTM-TEX/28295/2017 and UID/CTM/00264/2019