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- Discrimination between colorectal cancer patients and healthy individuals based on the urinary bolatilomic profilePublication . Viveiros, Francisca Silva; Câmara, José de SousaColorectal cancer (CRC) is the third most common and second most lethal cancer worldwide. The colon and rectum are both components of the gastrointestinal system, extending from the mouth to the anus. They play a crucial role in the digestion of food and beverages, responsible for the breakdown of consumed substances, nutrient absorption, and waste elimination. The objective of this thesis was to determine the urinary volatilomic profile of CRC patients and healthy individuals (HCs) through a non-invasive approach, aiming to identify potential biomarkers for diagnosis and treatment. Urine samples from HC subjects (n = 17) and CRC patients (n = 19) were analyzed using solid-phase microextraction combined with gas chromatography mass spectrometry (HS-SPME/GC MS), a sensitive and reliable methodology. A total of 68 volatile organic metabolites (VOMs) from both study groups were identified in this study. The chemical families that contributed the most were ketones, phenolic compounds, and norisoprenoids. Data were normalized using multivariate ANOVA followed by Turkey´s test (p < 0.05), which identified 30 VOMs with significant differences between groups, including several associated with oncological conditions and processes such a microbial dysbiosis, lipid peroxidation, and chronic intestinal inflammation. Subsequently, multivariate OPLS-DA analysis revealed a clear separation between groups, which highlighted important VOM. 2-Pentanone and 2,5-dimethylfuran were more associated with CRC group, and naphthalene, 2-acetylfuran, p-xylene, theaspirane, 2-ethyl-1-hexanol, hexanal, hemimelitene, and 1,2-dihyfro-1,1,6-trimethylnaphthalene with HCs. An important finding was the early detection of an individual initially classified as a control who was later diagnosed with metastatic cancer. This result highlights the strong discriminatory power of the urinary volatilomic profile developed in this study and confirms the hypothesis that metabolic alterations related to CRC can be detected in urine even before clinical diagnosis. However, to increase the robustness of this study, it would be necessary to increase the number of participants and obtain more relevant information such as diet, disease stage, and investigate other profiles such as proteomics and genomics.
- Low-cost apparatus for real-time sampling of water column based on internet of underwater thingsPublication . Freitas, João Pedro Batista Valente Pereira; Radeta, MarkoCom apenas 5% das profundezas oceânicas exploradas, o desafio de compreender os ecossistemas que residem na biodiversidade marinha e o seu impacto nas alterações climáticas é ainda muito presente. As variáveis oceanográficas essenciais são, tipicamente, avaliadas através de tecnologias de deteção remota e drones. Contudo, estes dispositivos oferecem ou uma baixa resolução com ampla cobertura espacial, ou uma elevada resolução com cobertura espacial limitada. Deste modo, esta dissertação explora a utilização da Internet das Coisas Subaquáticas e o seu papel na facilitação da amostragem da coluna de água, com o intuito de desenvolver uma importante ferramenta a bordo de embarcações de pequeno porte, através de um sistema inovador baseado na amostragem em tempo real da coluna de água, por meio de uma conexão por cabo, aumentando assim a resolução espacial de indicadores essenciais à biodiversidade. O sistema integra vários sensores com capacidade para medir diferentes parâmetros de forma interoperável, garantindo compatibilidade com diversos dispositivos, como portáteis, telemóveis e tablets, permitindo uma maior flexibilidade para especialistas a bordo de embarcações mais pequenas. A validação do sistema demonstra o seu potencial como uma ferramenta para a monitorização marinha.