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2016
Santos, TG, Miranda RM, Vieira TM, Farinha RA, Ferreira TJ, Quintino L, Vilaça P, de Carvalho CCCR.  2016.  Developments in micro- and nano-defects detection using bacterial cells. NDT & E International. 78:20-28. AbstractWebsite

This paper describes improvements to the Nondestructive Testing (NDT) technique recently proposed, based on the use of bacterial cell suspensions to identify micro- and nano-surface defects. New bacterial strains were used with magnetic fields to improve bacteria mobility. Different materials and defect morphologies were tested, including nanoindentation defects, micro-powder injection moulding components and micro-laser welding. Nanoindentations with 0.6 µm depth and 5.3 µm side length were successfully detected. Bacterial cells allow identifying different topographic attributes of the surfaces, such as roughness. Cracks of about 0.5 µm wide and 10 µm depth in a reference test block Type 1 were successfully detected.

Aroso, IM, Silva JC, Mano F, Ferreira ASD, Dionísio M, Sá-Nogueira I, Barreiros S, Reis RL, Paiva A, Duarte ARC.  2016.  Dissolution enhancement of active pharmaceutical ingredients by therapeutic deep eutectic systems. European Journal of Pharmaceutics and Biopharmaceutics. 98:57-66.Website
Echeverria, C, Fernandes SN, Almeida PL, Godinho MH.  2016.  Effect of cellulose nanocrystals in a cellulosic liquid crystal behaviour under low shear (regime I): Structure and molecular dynamics. European Polymer Journal. 84:675-684. AbstractWebsite

In the field of cellulosic liquid crystals, attempts to establish the relationship between structure/properties have been developed. Above a critical concentration in an aqueous solution, hydroxypropylcellulose self-assembles in order to form cholesteric liquid crystal phases (LC-HPC). In this work we aim to understand how the incorporation of a low content of cellulose nanocrystals (CNC) within LC-HPC/H2O (50 wt%), could influence the behaviour of the system when subjected to low shear rates, where the cholesteric phase still persists. The analysis of the deuterium spectrum and the T2 (transversal relaxation) values confirm that the mobility of LC-HPC at low shear rates is restricted due to CNC, and consequently so is the flow of the cholesteric polydomains. These effects are more evident in the LC-HPC sample containing 2 wt% of CNC; besides needing more strain units to induce some degree of order, the achieved degree of order is recovered faster when compared to the reference sample.

Pedroso, HA, Silveira CM, Almeida RM, Almeida A, Besson S, Moura I, Moura JJG, Almeida MG.  2016.  Electron transfer and docking between cytochrome cd1 nitrite reductase and different redox partners - A comparative study. Biochim Biophys Acta. 1857:1412-142104.279.Website
Krings, B-J, Weinberger N, Decker M.  2016.  Enabling a mobile and independent way of life for people with dementia - Needs-oriented technology development. Ageing and technology. Perspectives from the social sciences. :183-204., Bielefeld: transcript
Machado, C.  2016.  Estudo de Produção de Grisalhas Históricas. FCT-UNL. , Lisbon
Cruz, J, Figueiredo E, Corregidor V, Girginova PI, Alves LC, Cruz C, Silva RJC, Liritzis I.  2016.  First results on radiometric dating of metals by alpha spectrometry. microchemj124-608-2016.pdf
Cordeiro, M, Carlos FF, Pedrosa P, Lopez A, Baptista PV.  2016.  Gold Nanoparticles for Diagnostics: Advances towards Points of Care. Diagnostics. 6(4):43. AbstractWebsite

The remarkable physicochemical properties of gold nanoparticles (AuNPs) have prompted developments in the exploration of biomolecular interactions with AuNP-containing systems, in particular for biomedical applications in diagnostics. These systems show great promise in improving sensitivity, ease of operation and portability. Despite this endeavor, most platforms have yet to reach maturity and make their way into clinics or points of care (POC). Here, we present an overview of emerging and available molecular diagnostics using AuNPs for biomedical sensing that are currently being translated to the clinical setting.

João, CFC, Baptista AC, Ferreira IMM, Silva JC, Borges JP.  2016.  https://vtt.pure.elsevier.com/en/publications/transflexteg-large-area-transparent-thin-film-thermoelectric-devi. Fibrous and textile materials for composite applications. :261-299., Singapore: Springer Abstract

Cellulose and chitin are the two most abundant natural polysaccharides. Both have a semicrystalline microfibrillar structure from which nanofibres can be extracted. These nanofibres are rod-like microcrystals that can be used as nanoscale reinforcements in composites due to their outstanding mechanical properties. This chapter starts by reviewing the sources, extraction methods and properties of cellulose and chitin nanofibres. Then, their use in the fabrication of structural and functional nanocomposites and the applications that have been investigated are reviewed. Nanocomposites are materials with internal nano-sized structures. They benefit from the properties of the nanofillers: low density, nonabrasive, nontoxic, low cost, susceptibility to chemical modifications and biodegradability. Diverse manufacturing technologies have been used to produce films, fibres, foams, sponges, aerogels, etc. Given their natural origin and high stiffness, these polymers have attracted a lot of attention not only in the biomedical and tissue engineering fields but also in areas such as pharmaceutics, cosmetics, agriculture, biosensors and water treatment.

Thiel, C, Nijs W, Simões S, Schmidt J, van Zyl A, Schmid E.  2016.  The impact of the EU car CO2 regulation on the energy system and the role of electro-mobility to achieve transport decarbonisation. Energy Policy Journal. 96:153-166.
Mello, RLS, Almeida T.  2016.  Intersecções entre os campos da Arte e da Ciência. Mouseion: Revista do Museu e Arquivo Histórico de Salle. (ISSN: 1981-7207):39-51.Website
Gravato-Nobre, MJ, Vaz F, Filipe S, Chalmers R, Hodgkin J.  2016.  The invertebrate lysozyme effector ILYS-3 is systemically activated in response to danger signals and confers antimicrobial protection in C. elegans. PLoS Pathogens. 15:e1005826.
Soares, PIP, Laia C, Carvalho A, Pereira L, Coutinho J, Ferreira I, Novo C, Borges JP.  2016.  Iron oxide nanoparticles stabilized with a bilayer of oleic acid for magnetic hyperthermia and MRI applications. Applied Surface Science. 383:240-247. AbstractWebsite

Iron oxide nanoparticles (Fe3O4, IONPs) are promising candidates for several biomedical applications such as magnetic hyperthermia and as contrast agents for magnetic resonance imaging (MRI). However, their colloidal stability in physiological conditions hinders their application requiring the use of biocompatible surfactant agents. The present investigation focuses on obtaining highly stable IONPs, stabilized by the presence of an oleic acid bilayer. Critical aspects such as oleic acid concentration and pH were optimized to ensure maximum stability. NPs composed of an iron oxide core with an average diameter of 9 nm measured using transmission electron microscopy (TEM) form agglomerates with an hydrodynamic diameter of around 170 nm when dispersed in water in the presence of an oleic acid bilayer, remaining stable (zeta potential of −120 mV). Magnetic hyperthermia and the relaxivities measurements show high efficiency at neutral pH which enables their use for both magnetic hyperthermia and MRI.

Soares, PIP, Laia CAT, Carvalho A, Pereira LCJ, Coutinho JT, Ferreira IMM, Novo CMM, Borges JP.  2016.  Iron oxide nanoparticles stabilized with a bilayer of oleic acid for magnetic hyperthermia and MRI applications. Appl Surf Sci. 383:240-247. AbstractWebsite

Iron oxide nanoparticles (Fe3O4, IONPs) are promising candidates for several biomedical applications such as magnetic hyperthermia and as contrast agents for magnetic resonance imaging (MRI). However, their colloidal stability in physiological conditions hinders their application requiring the use of biocompatible surfactant agents. The present investigation focuses on obtaining highly stable IONPs, stabilized by the presence of an oleic acid bilayer. Critical aspects such as oleic acid concentration and pH were optimized to ensure maximum stability. NPs composed of an iron oxide core with an average diameter of 9 nm measured using transmission electron microscopy (TEM) form agglomerates with an hydrodynamic diameter of around 170 nm when dispersed in water in the presence of an oleic acid bilayer, remaining stable (zeta potential of −120 mV). Magnetic hyperthermia and the relaxivities measurements show high efficiency at neutral pH which enables their use for both magnetic hyperthermia and MRI.

Santos, T, Carvalho J, Corvo MC, Cabrita EJ, Queiroz JA, Cruz C.  2016.  L-tryptophan and dipeptide derivatives for supercoiled plasmid DNA purification. International Journal of Biological Macromolecules. 87:385-396.: Elsevier AbstractWebsite

The present study focus on the preparation of chromatography supports for affinity-based chromatography of supercoiled plasmid purification. Three l-tryptophan based supports are prepared through immobilization on epoxy-activated Sepharose and characterized by HR-MAS NMR. The SPR is employed for a fast screening of l-tryptophan derivatives, as potential ligands for the biorecognition of supercoiled isoform, as well as, to establish the suitable experimental conditions for the chromatography. The results reveal that the overall affinity is high (KD = 10−9 and 10−8 M) and the conditions tested show that the use of HEPES 100 mM enables the separation and purification of supercoiled at T = 10 °C. The STD-NMR is performed to accomplish the epitope mapping of the 5′-mononucleotides bound to l-tryptophan derivatives supports. The data shows that the interactions between the three supports and the 5′-mononucleotides are mainly hydrophobic and π–π stacking. The chromatography experiments are performed with l-tryptophan support and plasmids pVAX-LacZ and pPH600. The supercoiled isoform separation is achieved at T = 10 °C by decreasing the concentration of (NH4)2SO4 from 2.7 to 0 M in HEPES for pVAX-LacZ and 2.65 M to 0 M in HEPES for pPH600.

Overall, l-tryptophan derivatives can be a promising strategy to purify supercoiled for pharmaceutical applications.

Corvo, L, Mendo AS, Figueiredo S, Larguinho M, Gaspar R, Baptista PV, Fernandes AR.  2016.  Liposomes as delivery system of a Sn(IV) compound for cancer therapy. Pharmaceutical Research. 6(33):1351-8. AbstractWebsite

PROPOSE:
Tin complexes demonstrate antiproliferative activities in some case higher than cisplatin, with IC50 at the low micromolar range. We have previously showed that the cyclic trinuclear complex of Sn(IV) bearing an aromatic oximehydroxamic acid group [nBu2Sn(L)]3 (L=N,2-dihydroxy-5-[N-hydroxyethanimidoyl]benzamide) (MG85) shows high anti-proliferative activity, induces apoptosis and oxidative stress, and causes destabilization of tubulin microtubules, particularly in colorectal carcinoma cells. Despite the great efficacy towards cancer cells, this complex still shows some cytotoxicity to healthy cells. Targeted delivery of this complex specifically towards cancer cells might foster cancer treatment.
METHODS:
MG85 complex was encapsulated into liposomal formulation with and without an active targeting moiety and cancer and healthy cells cytotoxicity was evaluated.
RESULTS:
Encapsulation of MG85 complex in targeting PEGylated liposomes enhanced colorectal carcinoma (HCT116) cancer cell death when compared to free complex, whilst decreasing cytotoxicity in non-tumor cells. Labeling of liposomes with Rhodamine allowed assessing internalization in cells, which showed significant cell uptake after 6 h of incubation. Cetuximab was used as targeting moiety in the PEGylated liposomes that displayed higher internalization rate in HCT116 cells when compared with non-targeted liposomes, which seems to internalize via active binding of Cetuximab to cells.
CONCLUSIONS:
The proposed formulation open new avenues in the design of innovative transition metal-based vectorization systems that may be further extended to other novel metal complexes towards the improvement of their anti-cancer efficacy, which is usually hampered by solubility issues and/or toxicity to healthy tissues.

Simoes, SG, Gregório V, Seixas J.  2016.  Mapping fuel poverty in Portugal. Energy Procedia. 106:155–165.
Batalha, IL, Zhou H, Lilley K, Lowe CR, Roque ACA.  2016.  Mimicking nature: Phosphopeptide enrichment using combinatorial libraries of affinity ligands. Journal of Chromatography A. 1457:76–87.: Elsevier B.V. AbstractWebsite

Phosphorylation is a reversible post-translational modification of proteins that controls a plethora of cellular processes and triggers specific physiological responses, for which there is a need to develop tools to characterize phosphorylated targets efficiently. Here, a combinatorial library of triazine-based synthetic ligands comprising 64 small molecules has been rationally designed, synthesized and screened for the enrichment of phosphorylated peptides. The lead candidate (coined A8A3), composed of histidine and phenylalanine mimetic components, showed high binding capacity and selectivity for binding mono- and multi-phosphorylated peptides at pH 3. Ligand A8A3 was coupled onto both cross-linked agarose and magnetic nanoparticles, presenting higher binding capacities (100-fold higher) when immobilized on the magnetic support. The magnetic adsorbent was further screened against a tryptic digest of two phosphorylated proteins ($\alpha$- and $\beta$-caseins) and one non-phosphorylated protein (bovine serum albumin, BSA). The MALDI-TOF mass spectra of the eluted peptides allowed the identification of nine phosphopeptides, comprising both mono- and multi-phosphorylated peptides.

Batista, AG, Najdi S, Godinho DM, Serrano F, Ortigueira MD, Rato RT.  2016.  A Multichannel Time-Frequency and Multi-Wavelet Toolbox for Uterine Electromyography Processing and Visualisation. Computers in Biology and Medicine.. 76.1:178-191.
Salgueiro, CA, Dantas JM.  2016.  Multiheme Cytochromes. Multiheme Cytochromes. :1–39., Berlin, Heidelberg: Springer Berlin Heidelberg Abstract

n/a

João, C, Baptista AC, Ferreira I, Silva JC, Borges JP.  2016.  Natural Nanofibres for Composite Applications. Fibrous and Textile Materials for Composite Applications. (Sohel Rana, Raul Fangueiro, Eds.).:261-299., Singapore: Springer Singapore Abstract

Cellulose and chitin are the two most abundant natural polysaccharides. Both have a semicrystalline microfibrillar structure from which nanofibres can be extracted. These nanofibres are rod-like microcrystals that can be used as nanoscale reinforcements in composites due to their outstanding mechanical properties. This chapter starts by reviewing the sources, extraction methods and properties of cellulose and chitin nanofibres. Then, their use in the fabrication of structural and functional nanocomposites and the applications that have been investigated are reviewed. Nanocomposites are materials with internal nano-sized structures. They benefit from the properties of the nanofillers: low density, nonabrasive, nontoxic, low cost, susceptibility to chemical modifications and biodegradability. Diverse manufacturing technologies have been used to produce films, fibres, foams, sponges, aerogels, etc. Given their natural origin and high stiffness, these polymers have attracted a lot of attention not only in the biomedical and tissue engineering fields but also in areas such as pharmaceutics, cosmetics, agriculture, biosensors and water treatment.

Fundo, JF, Galvis-Sanchez A, Madureira AR, Carvalho A, Feio G, Silva CLM, Quintas MAC.  2016.  NMR water transverse relaxation time approach to understand storage stability of fresh-cut ‘Rocha’pear. LWT-Food Science and Technology. 74:280-285. AbstractWebsite

Fresh-cut fruit is an important segment in fruit market due to the increasing demand for healthy/convenient foods. However, processing promotes a decrease in fruits stability with faster physiological and microbiological deteriorations. Food stability is strongly attributed to its molecular dynamics and “water availability”. Understanding changes in water location/mobility is of utmost importance, since water dynamics profoundly influences physic-chemical and microbiological quality of foods. Nuclear magnetic resonance spectroscopy (NMR) is a methodology used to study the food constituents' molecular dynamics.

The aim of this study is to use NMR to evaluate changes in water mobility that occurred in fresh-cut pear tissues during storage, by measuring the transverse relaxation time (T2) parameter.

Results showed the existence of three water classes in the cells after processing, with T2 values of 10 ms, 187 ms and 3s for cellular wall, cytoplasm and vacuole, respectively. Also, the obtained results demonstrated that T2 was affected by processing and storage. Moreover, a relationship between T2, microstructure and the quality parameters was established. T2, maximum value increased with pear hardness as well as water activity. On the contrary, a decrease in total colour difference (TCD) was found with T2.

Results demonstrate the usefulness of the application of NMR relaxometry in food studies.

Mendes, R, Carreira B, Baptista PV, Fernandes AR.  2016.  Non-small lung cancer biomarkers and targeted therapy - two faces of the same coin fostered by Nanotechnology. Expert Review of Precision Medicine and Drug Development. 1(2):155-168. AbstractWebsite

Lung cancer is the leading cause of cancer-related mortality in the world, non-small lung cancer (NSCLC) is the most frequent subtype (85% of the cases). Within this subtype, adenocarcinoma and squamous cell carcinoma are the most frequent. New therapeutic strategies based on targeted delivery of drugs have relied on the use of biomarkers derived from the patients’ molecular profiling. Several biomarkers have been found to be useful for use as targets for precision therapy in NSCLC, such as mutations in the epidermal growth factor receptor, v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog, anaplastic lymphoma kinase, mesenchymal-epithelial transition factor receptor tyrosine kinase, BRAF, c-ros oncogene 1, P53 and phosphatase with tensin homology. Current developments in Nanomedicine have allowed for multifunctional systems capable of delivering therapeutics with increased precision to the target site/tissue, while simultaneously assisting in diagnosis. Here, we review the use of biomarkers in nanotechnology translation in NSCLC management.

Granadeiro, CM, Ribeiro SO, Kaczmarek AM, Cunha-Silva L, Almeida PL, Gago S, Van Deun R, de Castro B, Balula SS.  2016.  A novel red emitting material based on polyoxometalate@ periodic mesoporous organosilica. Microporous and Mesoporous Materials. 234:248-256. AbstractWebsite

The first lanthanopolyoxometalate-supported bifunctional periodic mesoporous organosilica (BPMO) composite is here reported. The incorporation of decatunsgstoeuropate anions ([Eu(W5O18)2]9−) within the porous channels of an ethylene-bridged TMAPS-functionalized BPMO produced a luminescent material exhibiting a strong red emission under UV irradiation. Photoluminescence studies showed an efficient energy transfer process to the lanthanide emitting center in the material (antenna effect). A significant change in the coordination environment of Eu3+ ions was observed after its incorporation into the TMAPS-functionalized material. The possible reason for this is discussed within the paper.

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