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- Concepção de uma rede de monitorização da qualidade da água com base nas pressões antropogénicasPublication . Pires, Débora; Matias, Christine; Lagoa, Ricardo
- New frontiers in biomedical science and engineering during 2014–2015Publication . Liu, Feng; Lee, Dong-Hoon; Lagoa, Ricardo; Kumar, Sandeep
- Evaluation of dry protonated calcium alginate beads for biosorption applications and studies of lead uptakePublication . Lagoa, Ricardo; Rodrigues, Joaquim RuiAlginate polysaccharide is a promising biosorbent for metal uptake. Dry protonated calcium alginate beads for biosorption applications were prepared, briefly characterized and tested for lead uptake. Several advantages of this biosorbent are reported and discussed in comparison with other alginate-based sorbents. The alginate beads contained 4.7 mmol/g of COOH groups, which suffered hydrolysis near pH 4. The Weber and Morris model, applied to kinetic results of lead uptake, showed that intraparticle diffusion was the rate-controlling step in lead sorption by dry alginate beads. Equilibrium experiments were performed and the data were fitted with different isotherm models. The Langmuir equation was the most adequate to model lead sorption. The maximum uptake capacity (qmax) was estimated as 339 mg/g and the Langmuir constant (b) as 0.84 l/mg. These values were compared with that of other sorbents found in the literature, indicating that dry protonated calcium alginate beads are among the best biosorbents for the treatment and recovery of heavy metals from aqueous streams.
- Kinetic studies of alginate gelationPublication . Rodrigues, Joaquim Rui; Lagoa, Ricardo
- Biopolymer-based manufacturing system for medical applicationsPublication . Lagoa, Ricardo; Bártolo, Paulo; Mendes, Ausenda
- Biochemical and anatomical basis of brain dysfunctions caused by cytochrome b5 reductase deficiency or dysregulationPublication . Samhan-Arias, Alejandro; López-Sánchez, Carmen; Marques-da-Silva, Dorinda; Lagoa, Ricardo; Garcia-Lopez, Virginio; García-Martínez, Virginio; Gutierrez-Merino, Carlos
- Qualidade microbiológica da água do rio LisPublication . Marques, S.; Maurício, S.; Costa, C.; Lagoa, Ricardo
- The decrease of NAD(P)H:quinone oxidoreductase 1 activity and increase of ROS production by NADPH oxidases are early biomarkers in doxorubicin cardiotoxicityPublication . Lagoa, Ricardo; Gañán, Carlos; López-Sánchez, Carmen; García-Martínez, Virginio; Gutierrez-Merino, Carlos
- Copper ions binding in cu‐alginate gelationPublication . Rodrigues, Joaquim Rui; Lagoa, RicardoAlginate polysaccharide forms viscous aqueous dispersions and has the ability to form gels in the presence of divalent cations such as calcium and copper. In this work, we have studied cooper ions binding during Cu‐alginate gelation, obtaining quantitative information about the amount and kinetics of cation binding. Our results indicate that copper binding during gelation occurs until a Langmuir‐type equilibrium is reached between bound and free ions in the gel‐contacting solution. The kinetics of metal ions binding can be modeled using Ritchie equation–derived models, allowing the prediction of ionic binding and gel formation temporal evolution. The ratio between cationic and polysaccharide quantities in the gelation system determines the kinetics of gelation and the characteristics of the gel formed. The experimental results and models applied in the work give more insights on alginate gelation and contribute to a reliable design and control of production methods for alginate gel structures.
- Anthocyanins, effects in mitochondria and metabolismPublication . Marques-da-Silva, Dorinda; Rodrigues, Joaquim Rui; Lagoa, RicardoAlterations in mitochondrial function, cellular redox signaling, and metabolism participate in the etiology and progression of different pathological conditions, such as diabetes, cancer, cardiovascular, and neurodegenerative diseases. Epidemiological, preclinical, and clinical studies indicate that anthocyanins afford therapeutic benefits for these pathologies. It is thus important to revise the effects of anthocyanins on mitochondria and metabolism that hold potential for the development of novel health protective methods. The studies available support the ability of certain anthocyanins to prevent damage to mitochondria and to sustain its function. Evidence is more compelling for cyanidin and delphinidin compounds, but promising data could also be found for malvidin, pelargonidin, and protocatechuic acid. Additionally, berry extracts also demonstrated positive outcomes in different models of neurodegeneration, endothelial dysfunction, myocardial damage, metabolic disorders, longevity, and cancer. At the molecular level, major anthocyanins can modulate the expression and activity of mitochondrial proteins, apoptotic and biogenesis factors, antioxidant defenses, inflammation, and the AMPK pathway. Noteworthy, anthocyanins could balance abnormalities in ROS production, respiration, and mitochondrial fragmentation in cells exposed to toxicants or oxidizing agents.