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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.
- Registered human trials addressing environmental and occupational toxicant exposures: Scoping review of immunological markers and protective strategiesPublication . Marques da Silva, Dorinda; Videira, Paula Alexandra; Lagoa, RicardoExposure to pollution is a worldwide societal challenge participating in the etiology and progression of different diseases. However, the scarce information hinders our understanding of the actual level of human exposure and its specific effects. Inadequate and excessive immune responses underlie diverse chronic diseases. Yet, it is unclear which and how toxicant exposures affect the immune system functions. There is a multiplicity of immunological outcomes and biomarkers being studied in human trials related to exposure to different toxicants but still without clear evidence of their value as biomarkers of exposure or effect. The main aim of this study was to collect scientific evidence and identify relevant immunological biomarkers used at the clinical level for toxicant exposures. We used the platform clinical trials.gov as a database tool. First, we performed a search combining research items related to toxicants and immunological parameters. The resulting117 clinical trials were examined for immune-related outcomes and specific biomarkers evaluated in subjects exposed to occupational and environmental toxicants. After categorization, relevant immunological outcomes and biomarkers were identified related to systemic and airway inflammation, modulation of immune cells, allergy and autoimmunity. In general, the immune markers related to inflammation are more frequently investigated for exposure to pollutants, namely IL-6, C-reactive protein (CRP) and nitric oxide (NO). Nevertheless, the data also indicated that prospective biomarkers of effect are gaining ground and a guiding representation of the established and novel biomarkers is suggested for upcoming trials. Finally, potential protective strategies to mitigate the adverse effects of specific toxicants are underlined for future studies.