Export 1532 results:
Sort by: Author Title Type [ Year  (Desc)]
2016
Avo, J, Petrov V, Basilio N, Parola AJ, Pina F.  2016.  Evidence against the Twisted Intramolecular Charge Transfer (TICT) model in 7-aminoflavylium derivatives, 2016. Dyes and Pigments. 135:86-93. AbstractWebsite
n/a
Lenis-Rojas, OA, Fernandes AR, Roma-Rodrigues C, Baptista PV, Marques F, Perez-Fernandez D, Guerra-Varela J, Sanchez L, Vazquez-Garcia D, Torres LM, Fernandez A, Fernandez JJ.  2016.  Heteroleptic mononuclear compounds of ruthenium(ii): synthesis, structural analyses, in vitro antitumor activity and in vivo toxicity on zebrafish embryos, 2016. Dalton Transactions. 45(47):19127-19140.: The Royal Society of Chemistry AbstractWebsite

The limitations of platinum complexes in cancer treatment have motivated the extensive investigation into other metal complexes such as ruthenium. We herein present the synthesis and characterization of a new family of ruthenium compounds 1a-5a with the general formula [Ru(bipy)2L][CF3SO3]2 (bipy = 2,2[prime or minute]-bipyridine; L = bidentate ligand: N,N; N,P; P,P; P,As) which have been characterized by elemental analysis, ES-MS, 1H and 31P-{1H} NMR, FTIR and conductivity measurements. The molecular structures of four Ru(ii) complexes were determined by single crystal X-ray diffraction. All compounds displayed moderate cytotoxic activity in vitro against human A2780 ovarian, MCF7 breast and HCT116 colorectal tumor cells. Compound 5a was the most cytotoxic compound against A2780 and MCF7 tumor cells with an IC50 of 4.75 +/- 2.82 [small mu ]M and 20.02 +/- 1.46 [small mu ]M, respectively. The compounds showed no cytotoxic effect on normal human primary fibroblasts but rather considerable selectivity for A2780, MCF7 and HCT116 tumor cells. All compounds induce apoptosis and autophagy in A2780 ovarian carcinoma cells and some nuclear DNA fragmentation. All compounds interact with CT-DNA with intrinsic binding constants in the order 1a > 4a > 2a > 3a > 5a. The observed hyperchromic effect may be due to the electrostatic interaction between positively charged cations and the negatively charged phosphate backbone at the periphery of the double helix-CT-DNA. Interestingly, compound 1a shows a concentration dependent DNA double strand cleavage. In addition in vivo toxicity has been evaluated on zebrafish embryos unveiling the differential toxicity between the compounds, with LC50 ranging from 8.67 mg L-1 for compound 1a to 170.30 mg L-1 for compound 2a.

Melo, CI, Szczepanska A, Bogel-Lukasik E, da Ponte MN, Branco LC.  2016.  Hydrogenation of Carbon Dioxide to Methane by Ruthenium Nanoparticles in Ionic Liquid, 2016. Chemsuschem. 9(10):1081-1084. AbstractWebsite
n/a
Pires, RF, Moro A, Lourenco A, Lima JC, Casimiro T, Bonifacio VDB.  2016.  Molecular Weight Determination by Luminescent Chemo-enzymatics, 2016. Chemistryselect. 1(21):6818-6822. AbstractWebsite
n/a
Santoro, S, Moro AJ, Portugal C, Crespo JG, Lima JC, Coelhoso IM.  2016.  Monitoring oxygen permeation through polymeric packaging films using a ratiometric luminescent sensor, 2016. Journal of Food Engineering. 189:37-44. AbstractWebsite
n/a
Tiago, GAO, Ribeiro APC, Mahmudov KT, da Silva MFCG, Branco LC, Pombeiro AJL.  2016.  Mononuclear copper(II) complexes of an arylhydrazone of 1H-indene-1,3(2H)-dione as catalysts for the oxidation of 1-phenylethanol in ionic liquid medium, 2016. Rsc Advances. 6(86):83412-83420. AbstractWebsite
n/a
Coutinho, ML, Miller AZ, Martin-Sanchez PM, Mirão J, Gomez-Bolea A, Machado-Moreira B, Cerqueira-Alves L, Jurado V, Saiz-Jimenez C, Lima A, Phillips AJL, Pina F, Macedo MF.  2016.  A multiproxy approach to evaluate biocidal treatments on biodeteriorated majolica glazed tiles, 2016. Environmental Microbiology. 18(12):4794-4816. AbstractWebsite
n/a
Basilio, N, Cruz L, de Freitas V, Pina F.  2016.  A Multistate Molecular Switch Based on the 6,8-Rearrangement in Bromo-apigeninidin Operated with pH and Host- Guest Inputs, 2016. Journal of Physical Chemistry B. 120(29):7053-7061. AbstractWebsite
n/a
Ruivo, A, Ferro M, Andrade SM, Rocha J, Pina F, Laia CAT.  2016.  Photoluminescent Nanocrystals in a Multicomponent Aluminoborosilicate Glass, 2016. Journal of Physical Chemistry C. 120(43):24925-24931. AbstractWebsite
n/a
Basilio, N, Garnier T, Avo J, Danel M, Chassaing S, Pina F.  2016.  Synthesis and multistate characterization of bis-flavylium dications - symmetric resorcinol- and phloroglucinol-type derivatives as stochastic systems, 2016. Rsc Advances. 6(74):69698-69707. AbstractWebsite
n/a
Bari, M, Loureiro J, Pudas M, Tappura K, Jaakola K, Ruoho M, Tittonen I, Volz S, Pavan C, Costabello K, Bollen D, Haslam M, Ferreira I.  2016.  TransFlexTeg: Large area transparent thin film thermoelectric devices for smart window and flexible applications, 20-23 Sep. 14th European Conference on Thermoelectrics, ECT 2016. Abstract

The main objective of TransFlexTeg is to develop an innovative large area distributed sensor network integrating transparent thin film thermoelectric devices and sensors for multifunctional smart windows and flexible high impact volume applications. Different breakthrough concepts will be developed: 1) large area high performance transparent thermoelectric thin films deposited on flexible substrates for thermal energy harvesting; 2) low cost high throughput thin film thermal sensors for thermal mapping and gesture sensing; 3) flexible smart windows and walls with energy harvesting, environmental sensing and wireless communication functionalities. This technology aims to demonstrate the functionalities of a smart window able to measure air quality and environmental parameters such as temperature, sun radiation and humidity. The data is automatically collected and can be utilized for controlling heating, cooling and ventilation systems of indoors. Active radio interface enables long range communication and long term data collection with WiFi or a similar base station. The proposed concept of smart windows replaces several conventional sensors with a distributed sensor network that is integrated invisibly into windows. In addition to the power generated from the thermal energy harvesting, the thermoelectric elements (TE) are also used as temperature sensors that, while being distributed over large area, enable thermal mapping of the area instead of just one or a few values measured from particular points. This smart window can be produced on glass. The active layer itself can be flexible glass layer or polymer sheet, which will significantly broaden the field of applications and improve business opportunities. Both can be manufactured in batch, or in Roll to Roll Atomic Layer Deposition (R2R ALD) process. High environmental impact is expected with savings of more than 25% of the electrical usage of residential homes and office buildings.

De Miglio, R, Chiodi A, Simoes S, Long G, Pollard M, Gouveia JP, Gargiulo M, Giannakidis G.  2016.  New methodological approach for planning cities sustainable and resilient energy futures – the case of the InSMART project, 1-3 June. International Energy Workshop. , Ireland: University College Cork
Raposo, LR, Roma-Rodrigues C, Faísca P, Alves M, Henriques J, Carvalheiro MC, Corvo LM, Baptista PV, Pombeiro AJL, Fernandes AR.  2016.   Immortalization and characterization of a new canine mammary tumor cell line FR37-CMT. J. Veterinary and Comparative Oncology. AbstractWebsite

Here we describe the establishment of a new canine mammary tumour (CMT) cell line, FR37-CMT that does not show dependence on female hormonal signaling to induce tumour xenografts in NOD-SCID mice. FR37-CMT cell line has a stellate or fusiform shape, displays the ability to reorganize the collagen matrix, expresses vimentin, CD44 and shows the loss of E-cadherin which is considered a fundamental event in epithelial to mesenchymal transition (EMT). The up-regulation of ZEB1, the detection of phosphorylated ERK1/2 and the downregulation of DICER1 and miR-200c are also in accordance with the mesenchymal characteristics of FR37-CMT cell line. FR37-CMT shows a higher resistance to cisplatin (IC50>50 µM) and to doxorubicin (IC50>5.3 µM) compared with other CMT cell lines. These results support the use of FR37-CMT as a new CMT model that may assist the understanding of the molecular mechanisms underlying EMT, CMT drug resistance, fostering the development of novel therapies targeting CMT.

Martins, M, Baptista PV, Mendo AS, Correia C, Videira P, Rodrigues AS, Muthukumaran J, Santos-Silva T, Silva A, da Silva FGMC, Gigante J, Duarte A, Pombeiro AJL, Fernandes AR.  2016.   In vitro and in vivo biological characterization of the anti-proliferative potential of a cyclic trinuclear organotin(IV) complex. Molecular BioSystems. (12) AbstractWebsite

Identification of novel molecules that can selectively inhibit the growth of tumor cells, avoid causing side effects to patients and/or intrinsic or acquired resistance, usually associated with common chemotherapeutic agents, is of utmost importance. Organometallic compounds have gained importance in oncologic chemotherapy, such as organotin(IV) complexes. In this study, we assessed the anti-tumor activity of the cyclic trinuclear organotin(IV) complex with an aromatic oximehydroxamic acid group [nBu2Sn(L)]3(H2L = N,2-dihydroxy-5-[N-hydroxyethanimidoyl]benzamide) – MG85 – and provided further characterization of its biological targets. We have previously shown the high anti-proliferative activity of this complex against human colorectal and hepatocellular carcinoma cell lines and lower cytotoxicity in neonatal non-tumor fibroblasts. MG85 induces tumor cell apoptosis and down-regulation of proteins related to tubulin dynamics (TCTP and COF1). Further characterization included the: (i) evaluation of interference in the cell cycle progression, including the expression of critical genes; (ii) affinity to DNA and the corresponding mode of binding; (iii) genotoxic potential in cells with deficient DNA repair pathways; and (iv) in vivo tumor reduction efficiency using mouse colorectal carcinoma xenografts.

Palma, SICJ, Fernandes AR, Roque ACA.  2016.  An affinity triggered MRI nanoprobe for pH-dependent cell labeling. RSC Adv.. 6:113503–113512., Number 114: Royal Society of Chemistry AbstractWebsite

The pH-sensitive affinity pair composed by neutravidin and iminobiotin was used to develop a multilayered Magnetic Resonance Imaging (MRI) nanoprobe responsive to the acidic pH of tumor microenvironment. The multilayer system was assembled on meso-2,3-dimercaptosuccinic acid-coated iron oxide magnetic nanoparticles (MNP), which convey negative MRI contrast enhancement properties to the nanoprobe. The outer stealth PEG-layer is altered in acidic media due to the disruption of interactions between neutravidin–iminobiotin. As a consequence, the positively charged inner layer is exposed and enhances interactions with cells. The nanoprobe uptake by HCT116 cells cultured in vitro under acidic conditions had a 2-fold increase compared to the uptake at physiological pH. The uptake difference is particularly clear in T2-weighted MRI phantoms of cells incubated with the nanoprobes at both pH conditions. This work sets the proof-of-concept of a MNP-based MRI nanoprobe targeting acidic tumor microenvironment through the use of a specific bio-recognition interaction that is pH-sensitive. This tumor targeting strategy is potentially applicable to the generality of tumors since the typical hypoxic conditions and high glycolysis rate in cancer cells create an acidic environment common to the majority of cancer types.

Fernandes, CSM, dos Santos R, Ottengy S, Viecinski AC, Béhar G, Mouratou B, Pecorari F, Roque ACA.  2016.  Affitins for protein purification by affinity magnetic fishing. Journal of Chromatography A. 1457:50–58.: Elsevier B.V. AbstractWebsite

Currently most economical and technological bottlenecks in protein production are placed in the down-stream processes. With the aim of increasing the efficiency and reducing the associated costs, variousaffinity ligands have been developed. Affitins are small, yet robust and easy to produce, proteins derivedfrom the archaeal extremophilic “7 kDa DNA-binding” protein family. By means of combinatorial pro-tein engineering and ribosome display selection techniques, Affitins have shown to bind a diversity oftargets. In this work, two previously developed Affitins (anti-lysozyme and anti-IgG) were immobilizedonto magnetic particles to assess their potential for protein purification by magnetic fishing. The opti-mal lysozyme and human IgG binding conditions yielded 58 mg lysozyme/g support and 165 mg IgG/gsupport, respectively. The recovery of proteins was possible in high yield (≥95{%}) and with high purity,namely ≥95{%} and 81{%}, when recovering lysozyme from Escherichia coli supernatant and IgG from humanplasma, respectively. Static binding studies indicated affinity constants of 5.0 × 104M−1and 9.3 × 105M−1for the anti-lysozyme and anti-IgG magnetic supports. This work demonstrated that Affitins, which canbe virtually evolved for any protein of interest, can be coupled onto magnetic particles creating novelaffinity adsorbents for purification by magnetic fishing.

Vaz, F, Covas G, Pinho MG, Filipe SR.  2016.  Analysis of cell wall teichoic acids in Staphylococcus aureus. Methods Mol. Biol. 1440:201-13.
Fortunato, Gaspar, Diana, Duarte, Candido, Pereira, Águas, Hugo, Vicente, António, Dourado, Fernando, Gama, F. M., Martins R.  2016.  Chapter 11 - Optoelectronic Devices from Bacterial NanoCellulose. Bacterial Nanocellulose. :19pp..: Elsevier Inc.
Vinhas, R, Cordeiro M, Pedrosa P, Fernandes AR, Baptista PV.  2016.  Current trends in molecular diagnostics of chronic myeloid leukemia. Leukemia & Lymphoma. :1-14. AbstractWebsite

Nearly 1.5 million people worldwide suffer from chronic myeloid leukemia (CML), characterized by the genetic translocation t(9;22)(q34;q11.2), involving the fusion of the Abelson oncogene (ABL1) with the breakpoint cluster region (BCR) gene. Early onset diagnosis coupled to current therapeutics allow for a treatment success rate of 90, which has focused research on the development of novel diagnostics approaches. In this review, we present a critical perspective on current strategies for CML diagnostics, comparing to gold standard methodologies and with an eye on the future trends on nanotheranostics.

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
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
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.

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.