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2010
Ramos, S, Almeida RM, Moura JJ, Aureliano M.  2010.  Implications of oxidovanadium(IV) binding to actin, Jun. J Inorg Biochem. 105:777-83., Number 6 AbstractWebsite

Oxidovanadium(IV), a cationic species (VO(2+)) of vanadium(IV), binds to several proteins, including actin. Upon titration with oxidovanadium(IV), approximately 100% quenching of the intrinsic fluorescence of monomeric actin purified from rabbit skeletal muscle (G-actin) was observed, with a V(50) of 131 muM, whereas for the polymerized form of actin (F-actin) 75% of quenching was obtained and a V(50) value of 320 muM. Stern-Volmer plots were used to estimate an oxidovanadium(IV)-actin dissociation constant, with K(d) of 8.2 muM and 64.1 muM VOSO(4), for G-actin and F-actin, respectively. These studies reveal the presence of a high affinity binding site for oxidovanadium(IV) in actin, producing local conformational changes near the tryptophans most accessible to water in the three-dimensional structure of actin. The actin conformational changes, also confirmed by (1)H NMR, are accompanied by changes in G-actin hydrophobic surface, but not in F-actin. The (1)H NMR spectra of G-actin treated with oxidovanadium(IV) clearly indicates changes in the resonances ascribed to methyl group and aliphatic regions as well as to aromatics and peptide-bond amide region. In parallel, it was verified that oxidovanadium(IV) prevents the G-actin polymerization into F-actin. In the 0-200 muM range, VOSO(4) inhibits 40% of the extent of polymerization with an IC(50) of 15.1 muM, whereas 500 muM VOSO(4) totally suppresses actin polymerization. The data strongly suggest that oxidovanadium(IV) binds to actin at specific binding sites preventing actin polymerization. By affecting actin structure and function, oxidovanadium(IV) might be responsible for many cellular effects described for vanadium.

de Martins, {RFP}, Fortunato {EMC}, Baptista {PMRV}, Águas {HMB}.  2010.  Inkjet printed and {"}doctor blade{"} TiO2 photodetectors for DNA biosensors, jan. Biosensors & Bioelectronics. 25:1229–1234., Number 5: Elsevier Abstract

A dye sensitized TiO2 photodetector has been integrated with a DNA detection method based on non-cross-linking hybridization of DNA-functionalized gold nanoparticles, resulting in a disposable colorimetric biosensor. We present a new approach for the fabrication of dye sensitized TiO2 photodetectors by an inkjet printing technique-a non-contact digital, additive, no mask and no vacuum patterning method, ideal for cost efficient mass production. The developed biosensor was compared against a dye sensitized photodetector fabricated by the traditional {"}doctor blade{"} method. Detection of gold nanoparticle aggregation was possible for concentrations as low as 1.0 nM for the {"}doctor blade{"} system, and 1.5 nM for the inkjet printed photodetector. The demonstrated sensitivity limits of developed biosensors; are comparable to those of spectrophotometric techniques (1.0 nM). Our results show that a difference higher than 17% by traditional photodetector and 6% by inkjet printed in the photoresponses for the complementary and non-complementary gold nanoprobe assays could be attained for a specific DNA sequence from Mycobacterium tuberculosis, the etiologic agent of human tuberculosis. The decrease of costs associated with molecular diagnostic provided by a platform such as the one presented here may prove of paramount importance in developing countries. (C) 2009 Elsevier B.V. All rights reserved.

Conde, J, {De La Fuente} {JM }, Baptista {PV}.  2010.  In vitro transcription and translation inhibition via DNA functionalized gold nanoparticles, dec. Nanotechnology. 21, Number 50: IOP Publishing Abstract

The use of gold nanoparticles (AuNPs) has been gaining momentum as vectors for gene silencing strategies, combining the AuNPs' ease of functionalization with DNA and/or siRNA, high loading capacity and fast uptake by target cells. Here, we used AuNP functionalized with thiolated oligonucleotides to specifically inhibit transcription in vitro, demonstrating the synergetic effect between AuNPs and a specific antisense sequence that blocks the T7 promoter region. Also, AuNPs efficiently protect the antisense oligonucleotide against nuclease degradation, which can thus retain its inhibitory potential. In addition, we demonstrate that AuNPs functionalized with a thiolated oligonucleotide complementary to the ribosome binding site and the start codon, effectively shut down in vitro translation. Together, these two approaches can provide for a simple yet robust experimental set up to test for efficient gene silencing of AuNP-DNA conjugates. What is more, these results show that appropriate functionalization of AuNPs can be used as a dual targeting approach to an enhanced control of gene expression-inhibition of both transcription and translation.

Dias, L, Gouveia J, Maurício B, Fortes P, Seixas J.  2010.  The impact of Climate Change Mitigation Options on Air Pollutant Emissions in Portugal, 24 June. Semiannual ETSAP Meeting 2010. , Stockholm, Sweden: KTH Royal Institute of Technology
Santos, TG, Vilaça P, dos Santos J, Quintino L, Rosado L.  2010.  Innovative eddy current probe for micro defects, 2010. 36th Annual Review of Progress in Quantitative Nondestructive Evaluation, QNDE. 1211:377-384., Kingston, RI Abstract
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Gomes, AQ, Correia DV, Grosso AR, Lança T, Ferreira C, Lacerda JF, Barata JT, da Silva MG, Silva-santos B.  2010.  Identification of a panel of ten cell surface protein antigens associated with immunotargeting of leukemias and lymphomas by peripheral blood γδT cells. Haematologica. 95:1397–1404., Number 8 AbstractWebsite

BACKGROUND:
Vgamma9Vdelta2 T lymphocytes are regarded as promising mediators of cancer immunotherapy due to their capacity to eliminate multiple experimental tumors, particularly within those of hematopoietic origin. However, Vgamma9Vdelta2 T-cell based lymphoma clinical trials have suffered from the lack of biomarkers that can be used as prognostic of therapeutic success.
DESIGN AND METHODS:
We have conducted a comprehensive study of gene expression in acute lymphoblastic leukemias and non-Hodgkin's lymphomas, aimed at identifying markers of susceptibility versus resistance to Vgamma9Vdelta2 T cell-mediated cytotoxicity. We employed cDNA microarrays and quantitative real-time PCR to screen 20 leukemia and lymphoma cell lines, and 23 primary hematopoietic tumor samples. These data were analyzed using state-of-the-art bioinformatics, and gene expression patterns were correlated with susceptibility to Vgamma9Vdelta2 T cell mediated cytolysis in vitro.
RESULTS:
We identified a panel of 10 genes encoding cell surface proteins that were statistically differentially expressed between "gammadelta-susceptible" and "gammadelta-resistant" hematopoietic tumors. Within this panel, 3 genes (ULBP1, TFR2 and IFITM1) were associated with increased susceptibility to Vgamma9Vdelta2 T-cell cytotoxicity, whereas the other 7 (CLEC2D, NRP2, SELL, PKD2, KCNK12, ITGA6 and SLAMF1) were enriched in resistant tumors. Furthermore, some of these candidates displayed a striking variance of expression among primary follicular lymphomas and T-cell acute lymphoblastic leukemias.
CONCLUSIONS:
Our results suggest that hematopoietic tumors display a highly variable repertoire of surface proteins that can impact on Vgamma9Vdelta2 cell-mediated immunotargeting. The prognostic value of the proposed markers can now be evaluated in upcoming Vgamma9Vdelta2 T cell-based lymphoma/leukemia clinical trials.

Paliokaité, A.  2010.  Industry level foresight: designing foresight methods for Lithuanian energy sector. Enterprise and Work Innovation Studies. 6:9-51. AbstractWebsite

This paper has its starting point in the background analysis of the Lithuanian energy sector after closing down the only Lithuanian nuclear power plant in 2010. Based on the hypothesis that one of the main governance failures in this sector leading to weak industry level strategies is the lack of participatory debate and sufficient linkages between the different actors involved in the dynamic of the energy sector in Lithuania, this paper proposes industry level foresight as an instrument of long term planning. Foresight exercises could become an important instrument for reorienting energy sector policy, building new networks and linkages among the different actors, bringing new stakeholders into the strategic debate, exploring future opportunities State investment (including R&D), etc. The primary objective of this paper is therefore the design of a foresight exercise on energy sector with the aim of producing a long term strategy for this sector. The secondary objective is to address a topic on how to select foresight methods at industry level. The argument is that a better understanding of the fundamental attributes of foresight methods and their linkages to the core phases of a foresight process can provide useful insights as to how the selection of methods is carried out. The method applied in this paper is dual: firstly, the synthesis of the academic literature on the selection of foresight methods is carried out; secondly, the comparative case study analysis of three foresight cases in the Baltic Sea Region (Poland, Finland and Russia) is applied. Case study analysis allows to explore the usage of foresight methods at industry level in the Baltic Sea Region and to understand if there are any similarities in the approach, also to explore success factors and weaknesses. The analysis in this paper is comprised of four main parts. The first part provides a background analysis on the energy sector in Lithuania and justification for the foresight exercise. Second part describes the underlying frameworks and definitions in the field of foresight research. The third part develops a comparative analysis of case studies of industry level foresight. The third part provides recommendations for energy sector foresight methodology in Lithuania. The paper combines concepts and frameworks from literature (such as the Foresight Process and the Foresight Diamond) with comparative practical case study analysis. The results can be utilised by lecturers and students to describe and understand better the use of foresight methods at industry level, and by practitioners of foresight to better inform decisions during the design of more coherent methodological frameworks; as well as by the energy sector stakeholders in Lithuania and other countries.

Olziersky, A, Barquinha P, Vila A, Pereira L, Goncalves G, Fortunato E, Martins R, Morante JR.  2010.  Insight on the SU-8 resist as passivation layer for transparent Ga2O3-In2O3-ZnO thin-film transistors. J. Appl. Phys.. 108(064505)
da Silva, JC.  2010.  A Integração da Componente Ambiental no Desenvolvimento dos Planos de Ordenamento do Território – o caso de Cabo Verde. Faculdade de Ciências e Tecnologia. (Amado, Miguel, Ed.)., Lisbon
Baptista, L, Melâneo P.  2010.  Interview - Miguel Amado. ARQA - Arquitectura e Arte. Website
Claro, A, Melo MJ, Seixas de Melo SJ, van den Berg KJ, Burnstock A, Montague M, Newman R.  2010.  Identification of red colorants in van Gogh paintings and ancient Andean textiles by microspectrofluorimetry. Journal of Cultural Heritage. 11:27-34., Number 1 AbstractWebsite
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Bicho, A, Roque ACA, Cardoso AS, Domingos P, Batalha ÍL.  2010.  In vitro studies with mammalian cell lines and gum arabic‐coated magnetic nanoparticles. Journal of Molecular Recognition. 23:536–542., Number 6 AbstractWebsite

Iron oxide magnetic nanoparticles {(MNPs)} were synthesized by the chemical co-precipitation method and coated with gum arabic {(GA)} by physical adsorption and covalent attachment. Cultures of mammalian cell lines {(HEK293}, {CHO} and {TE671)} were grown in the presence of uncoated and {GA-coated} {MNPs.} Cellular growth was followed by optical microscopy in order to assess the proportion of cells with particles, alterations in cellular density and the presence of debris. The in vitro assays demonstrated that cells from different origins are affected differently by the presence of the nanoparticles. Also, the methods followed for {GA} coating of {MNPs} endow distinct surface characteristics that probably underlie the observed differences when in contact with the cells. In general, the nanoparticles to which the {GA} was adsorbed had a smaller ability to attach to the cells' surface and to compromise the viability of the cultures. Copyright © 2010 John Wiley & Sons, Ltd.

Carrera, GVSM, Afonso CAM, Branco LC.  2010.  Interfacial Properties, Densities, and Contact Angles of Task Specific Ionic Liquids. Journal of Chemical and Engineering Data. 55:609-615., Number 2 AbstractWebsite
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Amarante, TR, Neves P, Coelho AC, Gago S, Valente AA, Paz FAA, Pillinger M, Goncalves IS.  2010.  Investigation of Molybdenum Tetracarbonyl Complexes As Precursors to Mo-VI Catalysts for the Epoxidation of Olefins. Organometallics. 29:883-892., Number 4 AbstractWebsite
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2009
Rivas, MG, Mota CS, Pauleta SR, Carepo MS, Folgosa F, Andrade SL, Fauque G, Pereira AS, Tavares P, Calvete JJ, Moura I, Moura JJ.  2009.  Isolation and characterization of a new Cu-Fe protein from Desulfovibrio aminophilus DSM12254, Oct. J Inorg Biochem. 103:1314-22., Number 10 AbstractWebsite

The isolation and characterization of a new metalloprotein containing Cu and Fe atoms is reported. The as-isolated Cu-Fe protein shows an UV-visible spectrum with absorption bands at 320 nm, 409 nm and 615 nm. Molecular mass of the native protein along with denaturating electrophoresis and mass spectrometry data show that this protein is a multimer consisting of 14+/-1 subunits of 15254.3+/-7.6 Da. Mossbauer spectroscopy data of the as-isolated Cu-Fe protein is consistent with the presence of [2Fe-2S](2+) centers. Data interpretation of the dithionite reduced protein suggest that the metallic cluster could be constituted by two ferromagnetically coupled [2Fe-2S](+) spin delocalized pairs. The biochemical properties of the Cu-Fe protein are similar to the recently reported molybdenum resistance associated protein from Desulfovibrio, D. alaskensis. Furthermore, a BLAST search from the DNA deduced amino acid sequence shows that the Cu-Fe protein has homology with proteins annotated as zinc resistance associated proteins from Desulfovibrio, D. alaskensis, D. vulgaris Hildenborough, D. piger ATCC 29098. These facts suggest a possible role of the Cu-Fe protein in metal tolerance.

Rivas, MG, Mota CS, Pauleta SR, Carepo MSP, Folgosa F, Andrade SLA, Fauque G, Pereira AS, Tavares P, Calvete JJ, Moura I, Moura JJG.  2009.  Isolation and characterization of a new Cu-Fe protein from Desulfovibrio aminophilus DSM12254, Oct. Journal Of Inorganic Biochemistry. {103}:{1314-1322}., Number {10, SI} Abstract

The isolation and characterization of a new metalloprotein containing Cu and Fe atoms is reported. The as-isolated Cu-Fe protein shows an UV-visible spectrum with absorption bands at 320 nm, 409 nm and 615 nm. Molecular mass of the native protein along with denaturating electrophoresis and mass spectrometry data show that this protein is a multimer consisting of 14 +/- 1 subunits of 15254.3 +/- 7.6 Da. Mossbauer spectroscopy data of the as-isolated Cu-Fe protein is consistent with the presence of [2Fe-2S](2+) centers. Data interpretation of the dithionite reduced protein suggest that the metallic cluster could be constituted by two ferromagnetically coupled [2Fe-2S](+) spin delocalized pairs. The biochemical properties of the Cu-Fe protein are similar to the recently reported molybdenum resistance associated protein from Desulfovibrio, D. alaskensis. Further-more, a BLAST search from the DNA deduced amino acid sequence shows that the Cu-Fe protein has homology with proteins annotated as zinc resistance associated proteins from Desulfovibrio, D. alaskensis, D. vulgaris Hildenborough, D. piger ATCC 29098. These facts suggest a possible role of the Cu-Fe protein in metal tolerance. (C) 2009 Published by Elsevier Inc.

Ivanova, G, Serafim LS, Lemos PC, Ramos AM, Reis MAM, Cabrita EJ.  2009.  Influence of feeding strategies of mixed microbial cultures on the chemical composition and microstructure of copolyesters P(3HB-co-3HV) analyzed by NMR and statistical analysis, JUN 2009. Magnetic Resonance in Chemistry. 47:497-504., Number 6 Abstract

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Branco, LC, Pina F.  2009.  Intrinsically photochromic ionic liquids. Chemical Communications. :6204-6206., Number 41 AbstractWebsite
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2008
de Martins, {RFP}, Baptista P, Silva {LB}, Raniero L, c}alo Dória G{\c, Franco R, Fortunato E.  2008.  Identification of unamplified genomic DNA sequences using gold nanoparticle probes and a novel thin film photodetector, may. Journal of Non-Crystalline Solids. 354:2580–2584., Number 19-25: Elsevier Abstract

This paper describes a novel colorimetric method for detection of nucleic acid targets in a homogeneous format with improved sensitivity by means of a system based on the combination of a tunable monochromatic light source and an amorphous/nanocrystalline silicon photodetector that detects color and light intensity changes undergone by samples/assays containing tailored gold nanoparticles probes. This new low cost, portable, fast and simple optoelectronic platform, with the possibility to be re-used, permits detection of at least 400 fentomole of specific DNA sequences without target or signal amplification and was applied to the rapid detection of human pathogens in large variety of clinical samples such as Mycobacterium tuberculosis.

Galesio, M, Vieira DV, Rial-Otero R, Lodeiro C, Moura I, Capelo JL.  2008.  Influence of the protein staining in the fast ultrasonic sample treatment for protein identification through peptide mass fingerprint and matrix-assisted laser desorption ionization time of flight mass spectrometry, May. Journal of Proteome Research. 7:2097-2106., Number 5 AbstractWebsite

The influence of the protein staining used to visualize protein bands, after in-gel protein separation, for the correct identification of proteins by peptide mass fingerprint (PMF) after application of the ultrasonic in-gel protein protocol was studied. Coomassie brilliant blue and silver nitrate, both visible stains, and the fluorescent dyes Sypro Red and Sypro Orange were evaluated. Results obtained after comparison with the overnight in-gel protocol showed that good results, in terms of protein sequence coverage and number of peptides matched, can be obtained with anyone of the four stains studied. Two minutes of enzymatic digestion time was enough for proteins stained with coomassie blue, while 4 min was necessary when silver or Sypro stainings were employed in order to reach equivalent results to those obtained for the overnigh in-gel protein protocol. For the silver nitrate stain, the concentration of silver present in the staining solution must be 0.09% (w/v) to minimize background in the MALDI mass spectra.

Santos, HM, Mota C, Lodeiro C, Moura I, Isaac I, Capelo JL.  2008.  An improved clean sonoreactor-based method for protein identification by mass spectrometry-based techniques, Dec 15. Talanta. 77:870-875., Number 2 AbstractWebsite

A new clean fast (8 min) method for in-solution protein digestion Without detergent or urea for protein identification by peptide mass fingerprint and mass spectrometry-based techniques is Proposed. The new method avoids the use of time consuming desalting procedures entailing the following four steps done under the effect of an ultrasonic field provided by a sonoreactor: denaturation (1 min) in a mixed Solution of water:acetonitrile 1/1 (v/v): protein reduction (1 min); protein alkylation (1 min); and protein digestion (5 min). Five Proteins with masses comprised between 14.4 kDa and 97 kDa and the protein splitsoret cytochrome c from D. desulfuricans ATCC27774, Were Successfully identified with this procedure. No differences were found in the sequence coverage or in the number of peptides matched when the new clean method was compared to another one using urea. Twofold better signal-to-noise ratios were obtained in the MALDI spectra from protein samples prepared with the new method when comparing it with a method using urea. The new digestion method avoids the need to remove salt content and increases throughput (six samples at once) while reducing sample loss and contamination from sample handling. (C) 2008 Elsevier B.V. All rights reserved.

Valério, D, Ortigueira MD, da Costa JSá.  2008.  Identifying a Transfer Function From a Frequency Response, April. Journal of Computational and Nonlinear Dynamics. 3:021207., Number 2 AbstractWebsite

In this paper, the classic Levy identification method is reviewed and reformulated using a complex representation. This new formulation addresses the well known bias of the classic method at low frequencies. The formulation is generic, coping with both integer order and fractional order transfer functions. A new algorithm based on a stacked matrix and its pseudoinverse is proposed to accommodate the data over a wide range of frequencies. Several simulation results are presented, together with a real system identification. This system is the Archimedes Wave Swing, a prototype of a device to convert the energy of sea waves into electricity.

Vidinha, P, Lourenco NMT, Pinheiro C, Bras AR, Carvalho T, Santos-Silva T, Mukhopadhyay A, Romao MJ, Parola J, Dionisio M, Cabral JMS, Afonso CAM, Barreiros S.  2008.  Ion jelly: a tailor-made conducting material for smart electrochemical devices, 2008. Chemical Communications. :5842-5844. AbstractWebsite

We present a new concept for the design of a polymeric conducting material that combines the chemical versatility of an organic salt ( ionic liquid) with the morphological versatility of a biopolymer ( gelatin); the resulting 'ion jelly' can be applied in electrochemical devices, such as batteries, fuel cells, electrochromic windows or photovoltaic cells.

Ortigueira, MD, Valerio D, da Costa JS.  2008.  Identifying a Transfer Function From a Frequency Response. Volume 5: 6th International Conference on Multibody Systems, Nonlinear Dynamics, and Control, Parts A, B, and C. :1405–1414. Abstract

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