Showing: 10 from total: 2413 publications
341.
A mitochondria-targeted caffeic acid derivative reverts cellular and mitochondrial defects in human skin fibroblasts from male sporadic Parkinson's disease patients (vol 45, 102037, 2021)
Deus, CM
; Pereira, SP
; Cunha Oliveira, T
; Teixeira, J
; Simoes, RF
; Cagide, F
; Benfeito, S
; Borges, F
; Raimundo, N
; Oliveira, PJ
in REDOX BIOLOGY, 2021, ISSN: 2213-2317, Volume: 47,
Correction, Indexed in: crossref, scopus, wos
Abstract
2.3. Cell culture conditions Skin fibroblasts from five sporadic late-onset PD (sPD) male patients and five age- and sex-matched healthy controls were obtained from a cell line repository of the Coriell Institute for Medical Research, USA (www.coriell.org), and their detailed information was previously described [43]. The repository ID numbers of control fibroblasts used were: ND29178, ND29179, ND34770, ND35044, and ND38530; the repository ID numbers of sPD fibroblasts used were: ND34265, ND35320, ND35322, ND35976, and ND39999.
342.
Novel propargylamine-based inhibitors of cholinesterases and monoamine oxidases: Synthesis, biological evaluation and docking study
Kratky, M
; Vu, QA
; Stepankova, S
; Maruca, A
; Silva, TB
; Ambroz, M
; Pflegr, V
; Rocca, R
; Svrckova, K
; Alcaro, S
; Borges, F
; Vinsova, J
in BIOORGANIC CHEMISTRY, 2021, ISSN: 0045-2068, Volume: 116,
Article, Indexed in: crossref, scopus, wos
Abstract
A combination of several pharmacophores in one molecule has been successfully used for multi-target-directed ligands (MTDL) design. New propargylamine substituted derivatives combined with salicylic and cinnamic scaffolds were designed and synthesized as potential cholinesterases and monoamine oxidases (MAOs) inhibitors. They were evaluated in vitro for inhibition of acetyl- (AChE) and butyrylcholinesterase (BuChE) using Ellman's method. All the compounds act as dual inhibitors. Most of the derivatives are stronger inhibitors of AChE, the best activity showed 5-bromo-N-(prop-2-yn-1-yl)salicylamide 1e (IC50 = 8.05 mu M). Carbamates (4-bromo-2[(prop-2-yn-1-yl)carbamoyl]phenyl ethyl(methyl)carbamate 2d and 2,4-dibromo-6-[(prop-2-yn-1-yl)carbamoyl] phenyl ethyl(methyl)carbamate 2e were selective and the most active for BuChE (25.10 and 26.09 mu M). 4-Bromo2-[(prop-2-yn-1-ylimino)methyl]phenol 4a was the most potent inhibitor of MAOs (IC50 of 3.95 and approximate to 10 mu M for MAO-B and MAO-A, respectively) along with a balanced inhibition of both cholinesterases being a real MTDL. The mechanism of action was proposed, and binding modes of the hits were studied by molecular docking on human enzymes. Some of the derivatives also exhibited antioxidant properties. In silico prediction of physicochemical parameters affirm that the molecules would be active after oral administration and able to reach brain tissue.
343.
Musical Control Gestures in Mobile Handheld Devices: Design Guidelines Informed by Daily User Experience
Clement, A
; Moreira, L
; Rosa, M
; Bernardes, G
in MULTIMODAL TECHNOLOGIES AND INTERACTION, 2021, Volume: 5,
Article, Indexed in: crossref, wos, dblp, scopus, handle
Abstract
Mobile handheld devices, such as smartphones and tablets, have become some of the most prominent ubiquitous terminals within the information and communication technology landscape. Their transformative power within the digital music domain changed the music ecosystem from production to distribution and consumption. Of interest here is the ever-expanding number of mobile music applications. Despite their growing popularity, their design in terms of interaction perception and control is highly arbitrary. It remains poorly addressed in related literature and lacks a clear, systematized approach. In this context, our paper aims to provide the first steps towards defining guidelines for optimal sonic interaction design practices in mobile music applications. Our design approach is informed by user data in appropriating mobile handheld devices. We conducted an experiment to learn links between control gestures and musical parameters, such as pitch, duration, and amplitude. A twofold action-reflection protocol and tool-set for evaluating the aforementioned links-are also proposed. The results collected from the experiment show statistically significant trends in pitch and duration control gesture mappings. On the other hand, amplitude appears to elicit a more diverse mapping approach, showing no definitive trend in this experiment.
344.
4-Oxoquinolines and monoamine oxidase: When tautomerism matters
Mesiti, F
; Maruca, A
; Silva, V
; Rocca, R
; Fernandes, C
; Remiao, F
; Uriarte, E
; Alcaro, S
; Gaspar, A
; Borges, F
in EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY, 2021, ISSN: 0223-5234, Volume: 213,
Article, Indexed in: crossref, scopus, wos
Abstract
4-Oxoquinoline derivatives have been often used in drug discovery programs due to their pharmacological properties. Inspired on chromone and 4-oxoquinoline chemical structure similarity, a small series of quinoline-based compounds was obtained and screened, for the first time, toward human monoamine oxidases isoforms. The data showed the N-(3,4-dichlorophenyl)-1-methyl-4-oxo-1,4-dihydroquinoline-3-carboxamide 10 was the most potent and selective MAO-B inhibitor (IC50 = 5.30 +/- 0.74 nM and SI: >= 1887). The data analysis showed that prototropic tautomerism markedly influences the biological activity. The unequivocal characterisation of the quinoline tautomers was performed to understand the attained data. To our knowledge, there have been no prior reports on the characterisation of quinolone tautomers by 2D NMR techniques, namely by H-1-N-15 HSQC and H-1-N-15 HMBC, which are proposed as expedite tools for medicinal chemistry campaigns. Computational studies on enzyme-ligand complexes, obtained after MM-GBSA calculations and molecular dynamics simulations, supported the experimental data.
345.
Mapping Chromone-3-Phenylcarboxamide Pharmacophore: Quid Est Veritas?
Mesiti, F
; Gaspar, A
; Chavarria, D
; Maruca, A
; Rocca, R
; Martins, EG
; Barreiro, S
; Silva, R
; Fernandes, C
; Gul, S
; Keminer, O
; Alcaro, S
; Borges, F
in JOURNAL OF MEDICINAL CHEMISTRY, 2021, ISSN: 0022-2623, Volume: 64,
Article, Indexed in: crossref, wos
Abstract
Chromone-3-phenylcarboxamides (Crom-1 and Crom-2) were identified as potent, selective, and reversible inhibitors of human monoamine oxidase B (hMAO-B). Since they exhibit some absorption, distribution, metabolism, and excretion (ADME)-toxicity liabilities, new derivatives were synthesized to map the chemical structural features that compose the pharmacophore, a process vital for lead optimization. Structure-activity relationship data, supported by molecular docking studies, provided a rationale for the contribution of the heterocycle's rigidity, the carbonyl group, and the benzopyran heteroatom for hMAO-B inhibitory activity. From the study, N-(3-chlorophenyl)-4H-thiochromone-3-carboxamide (31) (hMAO-B IC50 = 1.52 +/- 0.15 nM) emerged as a reversible tight binding inhibitor with an improved pharmacological profile. In in vitro ADME-toxicity studies, compound 31 showed a safe cytotoxicity profile in Caco-2, SH-SY5Y, HUVEC, HEK-293, and MCF-7 cells, did not present cardiotoxic effects, and did not affect P-gp transport activity. Compound 31 also protected SH-SY5Y cells from iron(III)-induced damage. Collectively, these studies highlighted compound 31 as the first-in-class and a suitable candidate for in vivo preclinical investigation.
346.
Preparation of molecularly imprinted hollow TiO2 microspheres for selective photocatalysis
Ferreira, VRA
; Azenha, MA
; Pereira, CM
; Silva, AF
in Chemical Engineering Journal Advances, 2021, ISSN: 2666-8211, Volume: 5,
Article, Indexed in: crossref, scopus
Abstract
Molecularly imprinted materials have been used in selective photocatalysis, essentially due to surface properties, possibility of reuse and low cost, that enhance their industrial and economic interest. The molecular imprinting technique allows the development of photocatalysts with selective recognition for a template molecule, used during synthesis, by increasing the surface area caused by selective recognition sites for the template used. In this work the preparation of hollow titania microspheres was merged with the process of generating selectivity for bilirubin in the shell structure by molecular imprinting. Three major synthesis parameters (solvent, temperature and TiO2 precursor) were studied by performing a set of experiments based in a full factorial design. The selected synthesis conditions were mainly dictated by the maximization of the surface area normalized by the thickness of the TiO2 shell and its controllability. The microspheres kept the integrity of the spherical shape while dispersed in the synthesis solvent. The observed imprinting features for the hollow microspheres prepared in the final synthesis conditions included imprinting factors of 3.1 for the binding strength and 1.3 for the capacity, and bilirubin/protoporphirin selectivity factors of 4.0 in terms of binding strength and 9.6 in terms of binding capacity. These features are very promising, especially the high selectivity factors, given the high resemblance between bilirubin and protoporphirin, and also due to the threat that the somewhat aggressive treatment for the silica core removal, might eventually pose to the templated microstructure of the shell. In fact, the photocatalytic selectivity of the imprinted microspheres was confirmed, with the observation of up to two-fold faster rates of bilirubin consumption vs. protoporphyrin consumption. © 2020
347.
Electrochemical and optical biosensing platforms for the immunorecognition of hazelnut Cor a 14 allergen
Costa, R
; Costa, J
; Sagastizábal, I
; Brandao, ATSC
; Moreira, P
; Mafra, I
; Silva, AF
; Pereira, CM
in FOOD CHEMISTRY, 2021, ISSN: 0308-8146, Volume: 361,
Article, Indexed in: crossref, scopus, unpaywall, wos
Abstract
Two immunosensors were advanced to target hazelnut Cor a 14 based on electrochemical and optical transduction. Both approaches were developed with two types of custom-made antibodies, namely anti-Cor a 14 IgG (rabbit) and anti-Cor a 14 IgY (hen's egg) targeting the Cor a 14 allergen. Antibody immobilisation was performed via EDC/NHS onto disposable screen-printed electrodes. The detection limit (LOD) of the electrochemical immunoassay for Cor a 14 was 5-times lower than the optical, being down to 0.05 fg mL-1 with a dynamic range of 0.1 fg mL-1 to 0.01 ng mL-1. Antibody selectivity was verified against non-target 2S albumins (potential crossreactive plant species). Anti-Cor a 14 IgY exhibited the best specificity, presenting minor cross-reactivity with peanut/walnut. Preliminary results of the application of anti-Cor a 14 IgY electrochemical immunosensor to incurred foods established a LOD of 1 mg kg- 1 of hazelnut in wheat (0.16 mg kg- 1 hazelnut protein).
348.
Sustainable Preparation of Nanoporous Carbons via Dry Ball Milling: Electrochemical Studies Using Nanocarbon Composite Electrodes and a Deep Eutectic Solvent as Electrolyte
Brandao, ATSC
; Costa, R
; Silva, AF
; Pereira, CM
in NANOMATERIALS, 2021, ISSN: 2079-4991, Volume: 11,
Article, Indexed in: crossref, scopus, wos
Abstract
The urgent need to reduce the consumption of fossil fuels drives the demand for renewable energy and has been attracting the interest of the scientific community to develop materials with improved energy storage properties. We propose a sustainable route to produce nanoporous carbon materials with a high-surface area from commercial graphite using a dry ball-milling procedure through a systematic study of the effects of dry ball-milling conditions on the properties of the modified carbons. The microstructure and morphology of the dry ball-milled graphite/carbon composites are characterized by BET (Brunauer-Emmett-Teller) analysis, SEM (scanning electron microscopy), ATR-FTIR (attenuated total reflectance-Fourier transform infrared spectroscopy) and Raman spectroscopy. As both the electrode and electrolyte play a significant role in any electrochemical energy storage device, the gravimetric capacitance was measured for ball-milled material/glassy carbon (GC) composite electrodes in contact with a deep eutectic solvent (DES) containing choline chloride and ethylene glycol as hydrogen bond donor (HBD) in a 1:2 molar ratio. Electrochemical stability was tracked by measuring charge/discharge curves. Carbons with different specific surface areas were tested and the relationship between the calculated capacitance and the surface treatment method was established. A five-fold increase in gravimetric capacitance, 25.27 F center dot g(-1) (G40) against 5.45 F center dot g(-1), was found for commercial graphene in contact with DES. Optimal milling time to achieve a higher surface area was also established.
349.
Characterization and electrochemical studies of MWCNTs decorated with Ag nanoparticles through pulse reversed current electrodeposition using a deep eutectic solvent for energy storage applications
Brandao, ATSC
; Rosoiu, S
; Costa, R
; Lazar, OA
; Silva, AF
; Anicai, L
; Pereira, CM
; Enachescu, M
in JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T, 2021, ISSN: 2238-7854, Volume: 15,
Article, Indexed in: crossref, scopus, wos
Abstract
Carbon nanotubes (CNTs) are receiving special attention due to their remarkable thermal, electrical, and mechanical properties. The present work reports an innovative synthesis procedure to decorate MWCNTs with silver nanoparticles (Ag-NPs) via pulsed reverse deposition technique using a deep eutectic solvent (DES) based on choline chloride and glycerol as an electrolyte at room temperature, not requiring any previous surface modification of MWCNTs. MWCNTs decorated with Ag-NPs disclose a significant enhancement of their electrochemical performance as demonstrated by the increase of electrode stability and specific capacitance. Electrochemical characterization of the composite material was performed using cyclic voltammetry and charge/discharge curves, achieving a specific capacitance up to 28.50 F. g-1, against 4.70 F. g-1 for the commercial MWCNTs in a three-electrode system. Retention of the specific capacitance up to 99% for the Ag-MWCNTs composites compared with a value of 78% for electrodes modified with commercial MWCNTs. The Ag-MWCNTs composites were characterized through SEM/EDX analysis, ultrahighresolution STEM, in which the Z - Contrast image was collected, and Raman analysis to prove the successful attachment of the Ag-NPs to the MWCNTs surface. AFM was performed to evaluate the conductivity of the composites. (c) 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
350.
Characterization and Comparison of the Relative Humidity Response of Hydromorphic Polymers in Long-Period Fiber Grating Structures
Dias, B
; Mendes, JP
; de Almeida, JMMM
; Coelho, LCC
in Chemistry Proceedings, 2021, Volume: 5,
Article, Indexed in: crossref
Abstract
<jats:p>Relative humidity monitorization is of extreme importance on scientific and industrial applications, and fiber optics-based sensors may provide solutions where other types of sensors have limitations. In this work, fiber optics’ sensors were fabricated by combining Long-Period Fiber Gratings with three different humidity-responding polymers, namely Poly(vinyl alcohol), Poly(ethylene glycol) and Hydromed™ D4. The performance of the multiple sensors was experimentally tested and crossed with numerical simulations, which provide a comparison with the expected response given the optical properties of the materials.</jats:p>