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2012
Ferraz, R, Branco LC, Marrucho IM, Araujo JMM, Rebelo LPN, da Ponte MN, Prudencio C, Noronha JP, Petrovski Z.  2012.  Development of novel ionic liquids based on ampicillin. Medchemcomm. 3:494-497., Number 4 AbstractWebsite
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Mendes, A, Branco LC, Morais C, Simplicio AL.  2012.  Electroosmotic flow modulation in capillary electrophoresis by organic cations from ionic liquids. Electrophoresis. 33:1182-1190., Number 7 AbstractWebsite
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dos} Santos, {MMM, Queiroz {MJ}, Baptista {PMRV}.  2012.  Enhancement of antibiotic effect via gold: silver-alloy nanoparticles. Journal Of Nanoparticle Research. 14:859–867., Number 5: Kluwer Academic Publishers Abstract

A strategy for the development of novel antimicrobials is to combine the stability and pleiotropic effects of inorganic compounds with the specificity and efficiency of organic compounds, such as antibiotics. Here we report on the use of gold:silver-alloy (Au:Ag-alloy) nanoparticles, obtained via a single-step citrate co-reduction method, combined to conventional antibiotics to enhance their antimicrobial effect on bacteria. Addition of the alloy nanoparticles considerably decreased the dose of antibiotic necessary to show antimicrobial effect, both for bacterial cells growing in rich medium in suspension and for bacterial cells resting in a physiological buffer on a humid cellulose surface. The observed effect was more pronounced than the sum of the individual effects of the nanoparticles and antibiotic. We demonstrate the enhancement effect of Au:Ag-alloy nanoparticles with a size distribution of 32.5±7.5nm mean diameter on the antimicrobial effect of (i) kanamycin onEscherichia coli(Gram-negative bacterium), and (ii) a β-lactam antibiotic on both a sensitive and resistant strain ofStaphylococcus aureus(Gram-positive bacterium). Together, these results may pave the way for the combined use of nanoparticle–antibiotic conjugates towards decreasing antibiotic resistance currently observed for certain bacteria and conventional antibiotics.

Bras, JLA, Carvalho AL, Viegas A, Najmudin S, Alves VD, Prates JAM, Ferreira LMA, Romao MJ, Gilbert HJ, Fontes CMGA.  2012.  ESCHERICHIA COLI EXPRESSION, PURIFICATION, CRYSTALLIZATION, AND STRUCTURE DETERMINATION OF BACTERIAL COHESIN-DOCKERIN COMPLEXES. Cellulases. 510(Gilbert, H. J., Ed.).:395-415. Abstract
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Gawande, MB, Velhinho A, Nogueira ID, Ghumman CAA, Teodoro OMND, Branco PS.  2012.  A facile synthesis of cysteine-ferrite magnetic nanoparticles for application in multicomponent reactions-a sustainable protocol. RSC ADVANCES. 2:6144-6149., Number 15 Abstract
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Rosa, J, Conde J, de la Fuente JM, Lima JC, Baptista PV.  2012.  Gold-nanobeacons for real-time monitoring of RNA synthesis. Biosensors & Bioelectronics. 36:161-167., Number 1 Abstract
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Gonzalez, J, Gavara R, Gadea O, Blasco S, Garcia-Espana E, Pina F.  2012.  Kinetics of Zn2+ complexation by a ditopic phenanthroline-azamacrocyclic scorpiand-like receptor. Chemical Communications. 48:1994-1996., Number 14 AbstractWebsite
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Conde, J, Rosa J, Lima JC, Baptista PV.  2012.  Nanophotonics for Molecular Diagnostics and Therapy Applications. International Journal of Photoenergy. Abstract
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Conde, J, Rosa J, Lima {JC }, Baptista {PV}.  2012.  Nanophotonics for molecular diagnostics and therapy applications. International Journal Of Photoenergy. 2012: Photoenergy Center / Hindawi Publishing Corporation Abstract

Light has always fascinated mankind and since the beginning of recorded history it has been both a subject of research and a tool for investigation of other phenomena. Today, with the advent of nanotechnology, the use of light has reached its own dimension where light-matter interactions take place at wavelength and subwavelength scales and where the physical/chemical nature of nanostructures controls the interactions. This is the field of nanophotonics which allows for the exploration and manipulation of light in and around nanostructures, single molecules, and molecular complexes. What is more is the use of nanophotonics in biomolecular interactionsnanobiophotonicshas prompt for a plethora of molecular diagnostics and therapeutics making use of the remarkable nanoscale properties. In this paper, we shall focus on the uses of nanobiophotonics for molecular diagnostics involving specific sequence characterization of nucleic acids and for gene delivery systems of relevance for therapy strategies. The use of nanobiophotonics for the combined diagnostics/therapeutics (theranostics) will also be addressed, with particular focus on those systems enabling the development of safer, more efficient, and specific platforms. Finally, the translation of nanophotonics for theranostics into the clinical setting will be discussed.

Conde, J, c}alo Doria G{\c, Baptista {PV}.  2012.  Noble metal nanoparticles applications in cancer. Journal of drug delivery. 2012:751075.: Hindawi Publishing Corporation Abstract

Nanotechnology has prompted new and improved materials for biomedical applications with particular emphasis in therapy and diagnostics. Special interest has been directed at providing enhanced molecular therapeutics for cancer, where conventional approaches do not effectively differentiate between cancerous and normal cells; that is, they lack specificity. This normally causes systemic toxicity and severe and adverse side effects with concomitant loss of quality of life. Because of their small size, nanoparticles can readily interact with biomolecules both at surface and inside cells, yielding better signals and target specificity for diagnostics and therapeutics. This way, a variety of nanoparticles with the possibility of diversified modification with biomolecules have been investigated for biomedical applications including their use in highly sensitive imaging assays, thermal ablation, and radiotherapy enhancement as well as drug and gene delivery and silencing. Here, we review the available noble metal nanoparticles for cancer therapy, with particular focus on those already being translated into clinical settings.

Bras, JLA, Alves VD, Carvalho AL, Najmudin S, Prates JAM, Ferreira LMA, Bolam DN, Romao MJ, Gilbert HJ, Fontes CMGA.  2012.  Novel Clostridium thermocellum Type I Cohesin-Dockerin Complexes Reveal a Single Binding Mode. Journal of Biological Chemistry. 287:44394-44405., Number 53 AbstractWebsite
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Pimenta, J, Dias FMV, Marques CC, Baptista MC, Vasques MI, Horta AEM, Barbas JP, Soares R, Mesquita P, Cabrita E, Fontes C, Prates JA, Pereira RM.  2012.  The Prion-like Protein Doppel Enhances Ovine Spermatozoa Fertilizing Ability. Reproduction in Domestic Animals. 47:196-202. Abstract

The function of prion-like protein Doppel was suggested to be related to male fertility. In this study, the importance of ovine Doppel polypeptide on spermatozoa capacitation and fertilization was evaluated. After refolding, recombinant Doppel (rDpl) was supplemented with different concentrations (40, 80 or 190 ng/ml) to ovine spermatozoa during the capacitation process. In experiment 1, post-thawed ovine spermatozoa were incubated with different concentrations of rDpl during 1 h for swim-up, and changes in sperm motility, concentration, vigour, viability and capacitation were monitored (10 replicates). In experiment 2, the fertilization ability of post-swim-up spermatozoa incubated as above was tested through heterologous fertilization of bovine in vitro matured oocytes (n = 423, three replicates). Regardless of dosage, rDpl improved (p = 0.03) spermatozoa viability. Sperm individual motility and vigour were the highest (p = 0.04) for the group receiving 190 ng/ml rDpl. Sperm supplemented with the highest doses of rDpl achieved higher (p = 0.02) fertilization rates (56.0 +/- 3.0%) than control (39.1 +/- 2.2%) and 40 ng/ml rDpl (39.8 +/- 2.7%). Preliminary data suggest that Doppel protein may enhance in vitro spermatozoa fertilizing ability.

da Silva, MS, Viveiros R, Aguiar-Ricardo A, Bonifacio VDB, Casimiro T.  2012.  Supercritical fluid technology as a new strategy for the development of semi-covalent molecularly imprinted materials. RSC Adv.. 2:5075-5079.: The Royal Society of Chemistry AbstractWebsite

Molecularly imprinted polymeric particles with molecular recognition towards Bisphenol A (BPA) were synthesized for the first time using the semi-covalent imprinting approach in supercritical carbon dioxide (scCO2). The material{'}s affinity to BPA was achieved by co-polymerizing ethylene glycol dimethacrylate (EGDMA) with a template-containing monomer{,} Bisphenol A dimethacrylate (BPADM) in scCO2. Bisphenol A is then cleaved from the polymeric matrix by hydrolysis with tetrabutylammonium hydroxide (n-Bu4OH) also in a supercritical environment{,} taking advantage of the high diffusivity of scCO2. The selectivity of the molecular imprinted polymer (MIP) was assessed by evaluating its capability to bind BPA in comparison with progesterone and [small alpha]-ethinylestradiol. In addition{,} the cross-linked particles were used to prepare a PMMA-based hybrid imprinted membrane by a scCO2-assisted phase inversion method. Results show that the incorporation of MIP particles was able to confer molecular affinity to BPA to the membrane and that at dynamic conditions of filtration{,} this imprinted porous structure was able to adsorb a higher amount of BPA than the corresponding non-imprinted hybrid membrane. Our work represents a valuable greener alternative to conventional methods{,} for the synthesis of affinity materials which are able to maintain molecular recognition properties in water.

Carrera, GVSM, da Ponte MN, Branco LC.  2012.  Synthesis and properties of reversible ionic liquids using CO2, mono- to multiple functionalization. Tetrahedron. 68:7408-7413., Number 36 AbstractWebsite
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Bazzicalupi, C, Biagini S, Bianchi A, Faggi E, Giorgi C, Gratteri P, Pina F, Valtancoli B.  2012.  Thermodynamic and fluorescence emission properties of the Zn(II), Cd(II) and Pb(II) complexes with a fluorescent chelator bearing phenanthroline and naphthalene subunits. Inorganica Chimica Acta. 381:229-235. AbstractWebsite
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Gordo, J, Máximo P{\'ıcia, Cabrita E, c}o AL{\c, Oliva A, Almeida J, Filipe M, Cruz P, Barcia R, Santos M, Cruz H.  2012.  Thymus mastichina: Chemical Constituents and their Anti-cancer Activity. Natural Product Communications. 7:1491-1494. Abstract
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Baltazar, P, Caires L, Vasconcelos VT, Vieira HT.  2012.  A Type System for Flexible Role Assignment in Multiparty Communicating Systems. Proceedings of the 7th International Symposium on Trustworthy Global Computing (TGC). Abstract
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Carvalho, T, Augusto V, Brás AR, c}o L{\cNMT, Afonso CAM, Barreiros S, Correia NT, Vidinha P, Cabrita EJ, Dion{\'ısio M, Roling B.  2012.  Understanding the Ion Jelly Conductivity Mechanism. Journal of Physical Chemistry B. 116:2664-2676. Abstract

The properties of the light flexible device, ion jelly, which combines gelatin with an ionic liquid (IL) were recently reported being promising to develop safe and highly conductive electrolytes. This article aims for the understanding of the ion jelly conductive mechanism using dielectric relaxation spectroscopy (DRS) in the frequency range 10-1-106 Hz; the study was complemented with differential scanning calorimetry (DSC) and pulse field gradient nuclear magnetic resonance (PFG NMR) spectroscopy. The room temperature ionic liquid 1-butyl-3-methylimmidazolium dicyanamide (BMIMDCA) used as received (1.9% w/w water content) and with 6.6% (w/w) of water content and two ion jellies with two different ratios BMIMDCA/gelatin/water % (w/w), IJ1 (41.1/46.7/12.2) and IJ3 (67.8/25.6/6.6), have been characterized. A glass transition was detected by DSC for all materials allowing for classifying them as glass formers. For the ionic liquid, it was observed that the glass transition temperature decreases with the increase of water content. While in subsequent calorimetric runs crystallization was observed for BMIMDCA with negligible water content, no crystallization was detected for any of the ion jelly materials upon themal cycling. To the dielectric spectra of all tested materials, both dipolar relaxation and conductivity contribute; at the lowest frequencies, electrode and interfacial polarization highly dominate. Conductivity, which manifests much more intensity relative to dipolar reorientations, strongly evidences subdiffusive ion dynamics at high frequencies. From dielectric measures, transport properties as mobility and diffusion coefficients were extracted. Data treatment was carried out in order to deconvolute the average diffusion coefficients estimated from dielectric data in its individual contributions of cations (D+) and anions (D-). The D+ values thus obtained for IJ3, the ion jelly with the highest IL/gelatin ratio, cover a large temperature range up to room temperature and revealed excellent agreement with direct measurements from PFG NMR, obeying to the same VFT equation. For BMIMDCA6.6%water, which has the same water amount as IJ3, the diffusion coefficients were only estimated from DRS measurements over a limited temperature range; however, a single VFT equation describes both DRS and PFG NMR data. Moreover, it was found that the diffusion coefficients and mobility are similar for the ionic liquid and IJ3, which points to a role of both water and gelatin weakening the contact ion pair, facilitating the translational motion of ions and promoting its dissociation; nevertheless, it is conceivable that a critical composition of gelatin that leads to those properties. The VFT temperature dependence observed for the conductivity was found to be determined by a similar dependence of the mobility. Both conductivity and segmental motion revealed to be correlated as inferred by the relatively low values of the decoupling indexes. The obtained results show that ion jelly could be in fact a very promising material to design novel electrolytes for different electrochemical devices, having a performance close to the IL but presenting an additional stability regarding electrical measurements and resistance against crystallization relative to the bulk ionic liquid.

Laranja, M, Boavida N.  2012.  {The use of indicators and evidence in governance and policy development of Science, Technology and Innovation}. , Number 07/2012: Universidade Nova de Lisboa, IET/CICS.NOVA-Interdisciplinary Centre on Social Sciences, Faculty of Science and Technology Abstract

In this paper we reflect upon how policy-makers look for, interpret and use evidence for reflection and policy development. We propose an exploratory framework that sets out two of the elements necessary to a conceptualization of what may explain the way in which evidence and indicators are used in STI policy development: the type of evaluative approach and the styles of governance.

Baquinha, P, Martins R, Pereira L, Fortunato E.  2012.  {Transparent Oxide Electronics}. : Wiley Abstract
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2011
Martins, {RFDP}, Baptista {PMRV}, Fortunato {EMC}.  2011.  Sistema de deteccion y cuantificacion de material biologico constituido por uno o mas sensores opticos y una o mas fuentes de luz, proceso asociado y aplicaciones relacionadas., sep. Abstract

Sistema para detección, identificación y cuantificación en material biológico, compuesto por una o más fuentes de luz (1) combinado con uno o más fotosensores ópticos (6 y 7) y diversos componentes electrónicos (4), necesarios para obtener/procesar la señal emitida caracterizado por: a) La fuente de luz (1), pulsada (2) o no, compuesta de láseres de estado sólido de baja energía o diodos emisores de luz, cuyo rango de longitud de onda está localizado entre 400 y 800 nm con una intensidad de luminosidad controlable que varía entre los valores de 0.01 mW/cm 2 y 100 mW/cm 2 ; b) El fotosensor, sencillo (6 y 7a) y (6 y 7b) o integrado (6, 4 y 7) compuesto de películas delgadas de silicio amorfo o nanocristalino o microcristalino y/o por semiconductores de cerámica tales como IGZO, IAgZO, SnZIO, GZIO, CuOIZ, GITO, entre otros, y basado en estructuras tipo pi'ii'n o MIS, que funciona en un rango de longitudes de onda desde el infrarrojo hasta el ultravioleta, y prové una información cualitativa y cuantitativa basada en la hibridización especifica y selectiva de sondas funcionalizadas con nanopartículas de metal; c) Siendo provista la eliminación del sistema a través de una fuente de energía convencional o a través de baterías fotovoltaicas, que dan portabilidad al sistema, siendo focalizada la luz emitida sobre la muestra, preferiblemente utilizando microlentes, siendo la muestra o muestras no fijadas físicamente al sensor o sensores, colocando la muestra biológica referida (5) sobre el lado opuesto (6) del sustrato donde se deposita el fotosensor (6 y 7).

Boavida, N.  2011.  {Decision making processes based on innovation indicators: which implications for technology assessment?}, November Enterprise and Work Innovation Studies. 7:33-55., Number 7 AbstractWebsite

The present work deals with the use of innovation indicators in the decision-making process. It intends to contribute to the discussion on the construction, use and analysis of indicator systems and also to evaluate its weight on decision-making in innovation. The goal is to help understand how innovation indicators can influence technology policy and through it, society at large. This work will start by analysing the use of indicators (their problems and consistency) and other sources of information that contribute to build the opinions of innovation decision makers. This will be followed by a survey and interviews with main innovation actors. The results will shed light on the impact of the use of indicators by the innovation community – both in terms of technology policy and in the social sphere. Proposals and implications for the future will be advanced, hopefully adding new contributions to the governance of the science, technology and innovation field.

Branquinho, R, Veigas B, {Vaz Pinto} J, de Martins {RFP}, Fortunato {EMC}, Baptista {PMRV}.  2011.  Real-time monitoring of PCR amplification of proto-oncogene c-MYC using a Ta₂O₅ electrolyte-insulator-semiconductor sensor, nov. Biosensors & Bioelectronics. 28:44–49., Number 1: Elsevier Abstract

We present a new approach for real-time monitoring of PCR amplification of a specific sequence from the human c-MYC proto-oncogene using a Ta(2)O(5) electrolyte-insulator-semiconductor (EIS) sensor. The response of the fabricated EIS sensor to cycle DNA amplification was evaluated and compared to standard SYBR-green fluorescence incorporation, showing it was possible to detect DNA concentration variations with 30 mV/μM sensitivity. The sensor's response was then optimized to follow in real-time the PCR amplification of c-MYC sequence from a genomic DNA sample attaining an amplification profile comparable to that of a standard real-time PCR. Owing to the small size, ease of fabrication and low-cost, the developed Ta(2)O(5) sensor may be incorporated onto a microfluidic device and then used for real-time PCR. Our approach may circumvent the practical and economical obstacles posed by current platforms that require an external fluorescence detector difficult to miniaturize and incorporate into a lab-on-chip system.

Mathies, G, Blok H, Disselhorst JA, Gast P, van der Meer H, Miedema DM, Almeida RM, Moura JJ, Hagen WR, Groenen EJ.  2011.  Continuous-wave EPR at 275GHz: application to high-spin Fe(3+) systems, May. J Magn Reson. 210:126-32., Number 1 AbstractWebsite

The 275GHz electron-paramagnetic-resonance spectrometer we reported on in 2004 has been equipped with a new probe head, which contains a cavity especially designed for operation in continuous-wave mode. The sensitivity and signal stability that is achieved with this new probe head is illustrated with 275GHz continuous-wave spectra of a 1mM frozen solution of the complex Fe(III)-ethylenediamine tetra-acetic acid and of 10mM frozen solutions of the protein rubredoxin, which contains Fe(3+) in its active site, from three different organisms. The high quality of the spectra of the rubredoxins allows the determination of the zero-field-splitting parameters with an accuracy of 0.5GHz. The success of our approach results partially from the enhanced absolute sensitivity, which can be reached using a single-mode cavity. At least as important is the signal stability that we were able to achieve with the new probe head.

Mota, CS, Valette O, Gonzalez PJ, Brondino CD, Moura JJ, Moura I, Dolla A, Rivas MG.  2011.  Effects of molybdate and tungstate on expression levels and biochemical characteristics of formate dehydrogenases produced by Desulfovibrio alaskensis NCIMB 13491, Jun. J Bacteriol. 193:2917-23., Number 12 AbstractWebsite

Formate dehydrogenases (FDHs) are enzymes that catalyze the formate oxidation to carbon dioxide and that contain either Mo or W in a mononuclear form in the active site. In the present work, the influence of Mo and W salts on the production of FDH by Desulfovibrio alaskensis NCIMB 13491 was studied. Two different FDHs, one containing W (W-FDH) and a second incorporating either Mo or W (Mo/W-FDH), were purified. Both enzymes were isolated from cells grown in a medium supplemented with 1 muM molybdate, whereas only the W-FDH was purified from cells cultured in medium supplemented with 10 muM tungstate. We demonstrated that the genes encoding the Mo/W-FDH are strongly downregulated by W and slightly upregulated by Mo. Metal effects on the expression level of the genes encoding the W-FDH were less significant. Furthermore, the expression levels of the genes encoding proteins involved in molybdate and tungstate transport are downregulated under the experimental conditions evaluated in this work. The molecular and biochemical properties of these enzymes and the selective incorporation of either Mo or W are discussed.

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