Publications

Abstract This article sums up three case studies carried out at a Portuguese science center, an elementary school, and a preschool, where storytelling and hands-on activities were combined. These studies produced indicators in line with the idea that appropriate and carefully chosen stories, combined with hands-on activities, may be a useful pedagogical approach to promote the attraction of young students to science and to teach some of its concepts. The hands-on activities, related to prior storytelling, seem to be a good way to involve students through listening, reading, imagining, understanding, making, and explaining, and thus can generate interest in science and scientific research. Furthermore, it is necessary to make a deeper assessment of the impact of those approaches on learning, development of scientific literacy, and the way young students perceive chemistry. © 2020 Societe Francaise de Chimie. All rights reserved.

Abstract The sodium-iodide symporter (NIS) mediates transport of iodide across the basolateral membrane of thyroid cells. NIS expression in thyroid cancer (TC) cells allows the use of radioactive iodine (RAI) as a diagnostic and therapeutic tool, being RAI therapy the systemic treatment of choice for metastatic disease. Still, a significant proportion of patients with advanced TC lose the ability to respond to RAI therapy and no effective alternative therapies are available. Defective NIS expression is the main reason for impaired iodide uptake in TC and NIS downregulation has been associated with several pathways linked to malignant transformation. NF-kappa B signaling is one of the pathways associated with TC. Interestingly, NIS expression can be negatively regulated by TNF-alpha, a bona fide activator of NF-kappa B with a central role in thyroid autoimmunity. This prompted us to clarify NF-kappa B's role in this process. We confirmed that TNF-alpha leads to downregulation of TSH-induced NIS expression in non-neoplastic thyroid follicular cell-derived models. Notably, a similar effect was observed when NF-kappa B activation was triggered independently of ligand-receptor specificity, using phorbol-myristate-acetate (PMA). TNF-alpha and PMA downregulation of NIS expression was reverted when NF-kappa B-dependent transcription was blocked, demonstrating the requirement for NF-kappa B activity. Additionally, TNF-alpha and PMA were shown to have a negative impact on TSH-induced iodide uptake, consistent with the observed transcriptional downregulation of NIS. Our data support the involvement of NF-kappa B-directed transcription in the modulation of NIS expression, where up-or down-regulation of NIS depends on the combined output to NF-kappa B of several converging pathways. A better understanding of the mechanisms underlying NIS expression in the context of normal thyroid physiology may guide the development of pharmacological strategies to increase the efficiency of iodide uptake. Such strategies would be extremely useful in improving the response to RAI therapy in refractory-TC.

Abstract An academic library created an online course in information literacy skills in 2007 for engineering students. This chapter reports the evaluation of the course's effectiveness in developing those skills. In the academic year 2015/2016, a case study with a mixed-methods approach was applied to 5th-year students (N=91) enrolled in a course unit for Master Dissertation's preparation in the informatics and computing engineering programme. Students showed high confidence in their information literacy skills. Online assignments' performance was good, but activities revealed quality issues. Performance in the course unit's assignments reveals a poor application of acquired skills. But satisfaction is high: students value independent learning and online access to resources and content. Despite evidence of some positive impact, the course lacks effectiveness due to issues in the course unit's assignments. Needed improvements include a better realignment with students' needs and a redesign with an instructional model to assure the promotion of students' success. © 2021 by IGI Global. All rights reserved.

Abstract In the present work, a detailed thermochemical, experimental and theoretical, study of benzocaine is presented. The enthalpy of formation in crystalline state at T = 298.15 K was obtained from combustion calorimetry experiments [ΔfHm°cr=-415.2±1.7kJ∙mol-1], within an oxygen atmosphere, using a static bomb calorimeter. The phase transition enthalpies (fusion, vaporization, and sublimation) were obtained by different techniques, namely differential scanning calorimetry, Calvet microcalorimetry, thermogravimetry, and the Knudsen effusion method. The results obtained by the different techniques are as follows: ΔcrlHm°298.15 K=21.4±0.1 kJ⋅mol−1; ΔlgHm°298.15 K=84.9±1.0 kJ⋅mol−1; ΔcrgHm°298.15 K=106.8±0.4 kJ⋅mol−1. From the experimental results, the enthalpy of formation of the aforesaid compound, in the gas phase, was calculated at T = 298.15 K as: ΔfHm°g=-308.4±1.8kJ∙mol-1. Theoretical enthalpies were computed using the Gaussian G4 composite method, atomization reactions, and the weighted Boltzmann average method. For the latter, the conformational diversity of the molecular structure of the compound was considered. Using the above data and using a similar approach, the theoretical entropy of benzocaine was computed as well. The experimental and theoretical values obtained were compared and an excellent accordance was found. Using the experimental and theoretical results, Gibbs energy of formation in crystalline and gaseous states of benzocaine, at T = 298.15 K were calculated as: ΔfGm°cr=-164.4kJ∙mol-1 and ΔfGm°g=-123.9kJ∙mol-1, respectively. Finally, the results obtained from the enthalpies of phase change are compared with those previously reported in the literature, in order to propose an exact value for these properties. © 2020 Elsevier Ltd

Abstract The energy involved in the structural switching of acyl and hydroxyl substituents in the title compounds was evaluated combining experimental and computational studies. Combustion calorimetry and Knudsen effusion techniques were used to determine the enthalpies of formation, in the crystalline state, and of sublimation, respectively. The gas-phase enthalpy of formation of both isomers was derived combining these two experimental data. Concerning the computational study, the G3(MP2)//B3LYP composite method was used to optimize and determine the energy of the isomers in the gaseous state. From a set of hypothetical reactions it has been possible to estimate the gas-phase enthalpy of formation of the title compounds. The good agreement between the experimental and computational gas-phase enthalpies of formation of the 1-acetyl-2-naphthol and 2-acetyl-1-naphthol isomers, provided the confidence for extending the computational study to the 2-acetyl-3-naphthol isomer. The structural rearrangement of the substituents in position 1 and 2 in the naphthalene ring and the energy of the intramolecular hydrogen bond are the factors responsible for the energetic differences exhibited by the isomers. The gas phase tautomeric keto <-> enol equilibria of theo-acetylnaphthol isomers were analyzed using the Boltzmann's distribution.

Abstract Ethnopharmacological use of plant natural extracts has been known since ancient times. The optimization of plant molecule extraction is fundamental in obtaining relevant extraction yields. The main purpose of this study was to understand the role of different extraction techniques (solid-liquid, ultrasound, Soxhlet, and microwave) and solvents (water, methanol, ethanol, acetone, dichloromethane, and hexane) on the antimicrobial and antioxidant activities of extracts from Olea europaea (olive) and Acacia dealbata (mimosa). Crude plant extracts were evaluated for their antimicrobial activity against Staphylococcus aureus and Escherichia coli by the disk diffusion method. The antioxidant capacity of the extracts was determined by ABTS (2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid)) and DPPH (2,2-diphenyl-1-picrylhydrazyl) methods. In terms of extraction yield, ultrasound extraction and the solvents methanol, acetone (O. europaea) or water (A. dealbata) were found to be the best options. However, ethanol and acetone proved to be the best solvents to extract compounds with antimicrobial activity and antioxidant capacity, respectively (regardless of the extraction method employed). Soxhlet and microwave were the best techniques to extract compounds with antimicrobial activity, whereas any of the tested techniques showed the ability to extract compounds with antioxidant capacity. In most of the cases, both plant extracts (mimosa and olive) were more efficient against S. aureus than E. coli. In the present study, both mimosa and olive leaf crude extracts proved to have antimicrobial and antioxidant activities, increasing the demand of these natural products as a source of compounds with health benefits.

Abstract Piperine has been associated with neuroprotective effects and monoamine oxidase (MAO) inhibition, thus being an attractive scaffold to develop new antiparkinsonian agents. Accordingly, we prepared a small library of piperine derivatives and screened the inhibitory activities towards human MAO isoforms (hMAO-A and hMAO-B). Structure-activity relationship (SAR) studies pointed out that the combination of alpha-cyano and benzyl ester groups increased both potency and selectivity towards hMAO-B. Kinetic experiments with compounds 7, 10 and 15 indicated a competitive hMAO-B inhibition mechanism. Compounds 15 and 16, at 10 mu M, caused a small but significant decrease in P-gp efflux activity in Caco-2 cells. Compound 15 stands out as the most potent piperine-based hMAO-B inhibitor (IC50 = 47.4 nM), displaying favourable drug-like properties and a broad safety window. Compound 15 is thus a suitable candidate for lead optimization and the development of multitarget-directed ligands.

Abstract This article presents a promising application of Fourier transform-mid infrared (FT-MIR) spectroscopy with multivariate curve resolution - alternating least-squares (MCR-ALS) as an at-line process analytical technology (PAT) to enhancing the understanding and continuous control of a pharmaceutical manufacturing process. Its objective was to monitor the synthesis of pharmaceutical multicomponent crystals in solid-state, namely the mixture between lamivudine (active pharmaceutical ingredient-API) and saccharin (coformer) using liquid assisted grinding (LAG) in proportion of 1:1 in a ball mill. The continuous monitoring of synthesis procedure ensured product quality, revealing some of the events that can be detected during mechanochemical synthesis by FT-MIR spectroscopy with MCR-ALS. The concentration profiles retrieved by MCR-ALS allowed to identify the end of the salt synthesis. In fact, this is one of the advantages of real-time monitoring using FT-MIR spectroscopy and MCR-ALS, because it can be helpful not only to monitor and control a pharmaceutical manufacturing process, but also to optimize efficient use of energy, time and raw materials for lamivudine-saccharinate salt synthesis. Moreover, it allowed to understand that the antiretroviral lamivudine-saccharinate salt synthetized by LAG showed a fast reaction mechanism due to the presence of ethanol as catalyst. Differential scanning calorimetry (DSC) and X-ray powder diffraction (XRPD) techniques provided additional information needed to fully characterize pharmaceutical lamivudine-saccharinate salt synthetized by LAG technique.

Abstract Alzheimer disease (AD) is the most common neurodegenerative disease featuring progressive and degenerative neurological impairments resulting in memory loss and cognitive decline. The specific mechanisms underlying AD are still poorly understood, but it is suggested that a deficiency in the brain neurotransmitter acetylcholine, the deposition of insoluble aggregates of fibrillar beta-amyloid 1-42 (A beta(42)), and iron and glutamate accumulation play an important role in the disease progress. Despite the existence of approved cholinergic drugs, none of them demonstrated effectiveness in modifying disease progression. Accordingly, the development of new chemical entities acting on more than one target is attracting progressively more attention as they can tackle intricate network targets and modulate their effects. Within this endeavor, a series of mitochondriotropic antioxidants inspired on hydroxycinnamic (HCA's) scaffold were synthesized, screened toward cholinesterases and evaluated as neuroprotectors in a differentiated human SH-SY5Y cell line. From the series, compounds 7 and 11 with a 10-carbon chain can be viewed as multi-target leads for the treatment of AD, as they act as dual and bifunctional cholinesterase inhibitors and prevent the neuronal damage caused by diverse aggressors related to protein misfolding and aggregation, iron accumulation and excitotoxicity.