Browsing by Author "Santos, Beatriz"
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- Cardiocerebral Infarction: A Combination to PreventPublication . Cabral, Margarida; Ponciano, Ana; Santos, Beatriz; Morais, JoãoBackground The acute complications of myocardial infarction (MI), such as mechanical, arrhythmic, ischemic, and inflammatory sequelae, may be responsible for significant cardiovascular morbimortality. Life-threatening arrhythmias, namely ventricular fibrillation or tachycardia, may be a challenging complication requiring a prompt approach. In some cases, acute ischemia leads to polymorphic ventricular tachycardia (PVT), and, rarely, to potentially lethal torsades de pointes ventricular tachycardia.
- Enhancement of the antioxidant and antimicrobial activities of porphyran through chemical modification with tyrosine derivativesPublication . Adão, Pedro; Reboleira, João; Teles, Marco; Santos, Beatriz; Ribeiro, Nádia; Teixeira, Carlos M.; Guedes, Mafalda; Pessoa, João Costa; Bernardino, Susana M.The chemical modification of porphyran hydrocolloid is attempted, with the objective of enhancing its antioxidant and antimicrobial activities. Sulfated galactan porphyran is obtained from commercial samples of the red algae Porphyra dioica using Soxhlet extraction with water at 100ºC and precipitation with isopropyl alcohol. The extracted porphyran is then treated with modified L-tyrosines in aqueous medium in the presence of NaOH, at ca. 70ºC. The modified tyrosines L1 and L2 are prepared through a Mannich reaction with either thymol or 2,4-di-tert-butylphenol, respectively. While the reaction with 2,4-di-tert-butylphenol yields the expected tyrosine derivative, a mixture of products is obtained with thymol. The resulting polysaccharides are structurally characterized and the respective antioxidant and antimicrobial activities are determined. Porphyran treated with the N-(2-hydroxy-3,5-di-tert-butyl-benzyl)-L-tyrosine derivative, POR-L2, presents a noticeable superior radical scavenging and antioxidant activity compared to native porphyran, POR. Furthermore, it exhibited some antimicrobial activity against S. aureus. The surface morphology of films prepared by casting with native and modified porphyrans is studied by SEM/EDS. Both POR and POR-L2 present potential applicability in the production of films and washable coatings for food packaging with improved protecting characteristics.
- Exuberant microvascular dysfunction: An indirect sign of coronary involvement in acute aortic syndrome?Publication . Cabral, Margarida; Martins, Hélia; Santos, Beatriz; Sousa, Pedro Jerónimo de; Morais, JoãoA 75-year-old obese woman with dyslipidemia and hypertension was admitted for acute chest pain. She presented anterolateral ST-segment elevationand slightly elevated troponin levels. She was transferred to a percutaneous coronary intervention-capable centre.
- Objectively Measured Physical Activity and Sedentary Behaviour on Cardiovascular Risk and Health-Related Quality of Life in Adults: A Systematic ReviewPublication . Santos, Beatriz; Monteiro, Diogo; Silva, Fernanda; Flores, Gonçalo; Bento, T.; Duarte-Mendes, PedroBackground: This systematic review analysed the association between objectively measured physical activity and sedentary behaviour with cardiovascular risk and HRQoL in adults without previous CVD. Additionally, we analysed the impact of the intensity of the physical activity in this association. Methods: The search was carried out in three electronic databases with access until February 2023 to find studies with an observational design. For quality assessment, we used The National Institute of Health (NIH) Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Results: We identified 5819 references, but only five studies were included. One study shows a positive association between physical activity and HRQoL, while sedentary behaviour was negatively related to HRQoL. Another study showed an association between high-intensity physical activity with a better physical component of HRQoL and low-intensity physical activity with a better mental component of HRQoL. Three studies concluded that higher levels of physical activity are associated with lower levels of cardiovascular risk and higher levels of sedentary behaviour are associated with higher levels of cardiovascular risk. Conclusion: Our findings suggested that people who spend more time being active and spend less time being sedentary appear to have lower cardiovascular risk and higher HRQoL.