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2017
Conceição, DS, Graça CAL, Ferreira DP, Ferraria AM, Fonseca IM, do Rego BAM, Teixeira ACSC, Ferreira VLF.  2017.  Photochemical insights of TiO2 decorated mesoporous SBA-15 materials and their influence on the photodegradation of organic contaminants. Microporous and Mesoporous Materials. 253:203-214. AbstractWebsite

Mesoporous silica, SBA-15, decorated with different amounts of TiO2 (anatase) were prepared by a sol-gel method followed by hydrothermal treatment and calcination, in the presence of a soft template, copolymer Pluronic 123. Tetraethyl orthosilicate (TEOS) was used as the SiO2 precursor and commercially available TiO2 anatase nanoparticles as the supported photocatalyst. The materials were characterized by transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDS), N2 adsorption-desorption isotherms, raman spectroscopy, ground state diffuse reflectance (GSDR), laser induced luminescence (LIL) and X-ray photoelectron spectroscopy (XPS). The zeta potentials of the pure SBA-15, TiO2/SBA-15 substrate and the commercial anatase sample were monitored through a complete range of pH values. All the nanomaterials developed in this work were studied in terms of their photoactivity in the UV range and in the visible range, separately. In the first case, hydroxyl radicals (OH) were confirmed to be the key active oxidizers in the photodegradation of the pesticide amicarbazone in aqueous medium. On the other hand, in the visible range, and following a dye sensitization process via a fluorescent rhodamine-like dye, two different mechanisms could be identified for the formation of the superoxide radical anion, O2−.

Matos, I, Bernardo M, Fonseca I.  2017.  Porous carbon: A versatile material for catalysis. Catalysis Today. 285:194-203. AbstractWebsite

Heterogeneous catalysis is an exciting field in constant development. New and improved catalysts that can both be effective and economical are always on demand. Activated carbons may well play an important role in this field, as they are a cheaper alternative while more environmentally benign. In this paper, a brief overview of the effort developed in the application of activated carbon as heterogeneous catalysts in various reactions is presented. Functionalised activated carbon has been used as catalyst for fine chemical reactions. Gas-phase reactions for NO, N2O and CO2 conversions were thoroughly studied using activated carbon as catalyst support. In situ characterization techniques proved to be valuable tools to understand carbon gasification mechanism.

Dias, D, Lapa N, Bernardo M, Godinho D, Fonseca I, Miranda M, Pinto F, Lemos F.  2017.  Properties of chars from the gasification and pyrolysis of rice waste streams towards their valorisation as adsorbent materials. Waste Management. 65:186-194. AbstractWebsite

Rice straw (RS), rice husk (RH) and polyethylene (PE) were blended and submitted to gasification and pyrolysis processes. The chars obtained were submitted to textural, chemical, and ecotoxic characterisations, towards their possible valorisation. Gasification chars were mainly composed of ashes (73.4–89.8wt%), while pyrolysis chars were mainly composed of carbon (53.0–57.6wt%). Silicon (Si) was the major mineral element in all chars followed by alkaline and alkaline-earth metal species (AAEMs). In the pyrolysis chars, titanium (Ti) was also a major element, as the feedstock blends contained high fractions of PE which was the main source of Ti. Gasification chars showed higher surface areas (26.9–62.9m2g−1) and some microporosity, attributed to porous silica. On the contrary, pyrolysis chars did not present a porous matrix, mainly due to their high volatile matter content. The gasification bed char produced with 100% RH, at 850°C, with O2 as gasification agent, was selected for further characterization. This char presented the higher potential to be valorised as adsorbent material (higher surface area, higher content of metal cations with exchangeable capacity, and lowest concentrations of toxic heavy metals). The char was submitted to an aqueous leaching test to assess the mobility of chemical species and the ecotoxic level for V. fischeri. It was observed that metallic elements were significantly retained in the char, which was attributed mainly to its alkaline character. This alkaline condition promoted some ecotoxicity level on the char eluate that was eliminated after the pH correction.

2016
Baptista, {PV}.  2016.  Precision nanomedicine in cancer: how far are we from personalization?, may Expert Review of Precision Medicine and Drug Development. 1:227–228., Number 3: Taylor & Francis Abstract
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Roma-Rodrigues, C, Heuer-Jungemann A, Fernandes AR, Kanaras AG, Baptista PV.  2016.  Peptide-coated gold nanoparticles for modulation of angiogenesis in vivo, 2016. 11 Abstract
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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
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Posa, I, Carvalho S, Tavares J, Grosso AR.  2016.  A pan-cancer analysis of MYC-PVT1 reveals CNV-unmediated deregulation and poor prognosis in renal carcinoma. Oncotarget. AbstractWebsite

The PVT1 lncRNA has recently been involved in tumorigenesis by affecting the protein stability of the MYC proto-oncogene. Both MYC and PVT1 reside in a well-known cancer-risk locus and enhanced levels of their products have been reported in different human cancers. Nonetheless, the extension and relevance of the MYC-PVT1 deregulation in tumorigenesis has not yet been systematically addressed.Here we performed a pan-cancer analysis of matched copy number, transcriptomic, methylation, proteomic and clinicopathological profiles for almost 7000 patients from 17 different cancers represented in the TCGA cohorts. Among all cancers types, kidney renal clear cell carcinoma (KIRC) showed the strongest upregulation of PVT1 and increased levels of both MYC and PVT1 correlated with the clinical outcome. PVT1 misregulation in KIRC is mostly associated to promoter hypomethylation rather than locus amplification. Furthermore, we found an association between MYC levels and PVT1 expression, which impacted on MYC-target genes.Collectively, our study discloses the role of PVT1 as a novel prognostic factor and as a molecular target for novel therapeutic interventions in renal carcinoma.

Machado, C, Machado A, Alves LC, Vilarigues M.  2016.  The past and the present: Commercial grisailles from Debitus. Proceedings of the 5th International Conference Youth in Conservation of Cultural Heritage – YOCOCU. , Madrid
Roma-Rodrigues, C, Heuer-Jungemann A, Fernandes AR, Kanaras AG, Baptista PV.  2016.  Peptide coated gold nanoparticles for in vivo targeting of angiogenesis. International J. Nanomedicine. (11):2633–2639. AbstractWebsite

In this work, peptides designed to selectively interact with cellular receptors involved in the regulation of angiogenesis were anchored to oligo-ethylene glycol-capped gold nanoparticles (AuNPs) and used to evaluate the modulation of vascular development using an ex ovo chick chorioallantoic membrane assay. These nanoparticles alter the balance between naturally secreted pro- and antiangiogenic factors, under various biological conditions, without causing toxicity. Exposure of chorioallantoic membranes to AuNP–peptide activators of angiogenesis accelerated the formation of new arterioles when compared to scrambled peptide-coated nanoparticles. On the other hand, antiangiogenic AuNP–peptide conjugates were able to selectively inhibit angiogenesis in vivo. We demonstrated that AuNP vectorization is crucial for enhancing the effect of active peptides. Our data showed for the first time the effective control of activation or inhibition of blood vessel formation in chick embryo via AuNP-based formulations suitable for the selective modulation of angiogenesis, which is of paramount importance in applications where promotion of vascular growth is desirable (eg, wound healing) or ought to be contravened, as in cancer development.

Batalha, ÍL, Roque ACA.  2016.  Petasis-Ugi ligands: New affinity tools for the enrichment of phosphorylated peptides. Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences. 1031:86–93.: Elsevier B.V. AbstractWebsite

Affinity chromatography is a widespread technique for the enrichment and isolation of biologics, which relies on the selective and reversible interaction between affinity ligands and target molecules. Small synthetic affinity ligands are valuable alternatives due to their robustness, low cost and fast ligand development. This work reports, for the first time, the use of a sequential Petasis-Ugi multicomponent reaction to generate rationally designed solid-phase combinatorial libraries of small synthetic ligands, which can be screened for the selection of new affinity adsorbents towards biological targets. As a proof of concept, the Petasis-Ugi reaction was here employed in the discovery of affinity ligands suitable for phosphopeptide enrichment. A combinatorial library of 84 ligands was designed, synthesized on a chromatographic solid support and screened in situ for the specific binding of phosphopeptides binding human BRCA1C-terminal domains. The success of the reaction on the chromatographic matrix was confirmed by both inductively coupled plasma atomic emission spectroscopy and fluorescence microscopy. Three lead ligands were identified due to their superior performance in terms of binding capacity and selectivity towards the phosphorylated moiety on peptides, which showed the feasibility of the Petasis-Ugi reaction for affinity ligand development.

Batalha, ÍL, Roque ACA.  2016.  Phosphopeptide Enrichment Using Various Magnetic Nanocomposites: An Overview. Phospho-Proteomics. 1355(Methods in Molecular Biology):193–209. AbstractWebsite

Magnetic nanocomposites are hybrid structures consisting of an iron oxide (Fe3O4 /$\gamma$-Fe2O3 ) superparamagnetic core and a coating shell which presents affi nity for a specifi c target molecule. Within the scope of phosphopeptide enrichment, the magnetic core is usually fi rst functionalized with an intermediate layer of silica or carbon to improve dispersibility and increase specifi c area, and then with an outer layer of a phosphate-affi nity material. Fe3O4 -coating materials include metal oxides, rare earth metal-based compounds, immobilized-metal ions, polymers, and many others. This chapter provides a generic overview of the different materials that can be found in literature and their advantages and drawbacks.

Ruivo, A, Andrade S, Ferro M, Rocha J, Laia C, Pina F.  2016.  Photoluminescent Nanocrystals in a Multicomponent Aluminoborosilicate Glass. Journal of Physical Chemistry C. 120:24925−24931.
Almeida, RM, Dell'Acqua S, Krippahl L, Moura JJG, Pauleta SR.  2016.  Predicting Protein-Protein Interactions Using BiGGER: Case Studies. Molecules. 21:1037.Website
Craveiro, R, Aroso I, Flammia V, Carvalho T, Viciosa MT, Dionísio M, Barreiros S, Reis RL, Duarte ARC, Paiva A.  2016.  Properties and thermal behavior of natural deep eutectic solvents. Journal of Molecular Liquids. 215:534-540.Website
Yang, Y, Wikieł AJ, Dall'agnol LT, Eloy P, Genet MJ, Moura JJG, Sand W, Dupont-Gillain CC, Rouxhet PG.  2016.  Proteins dominate in the surface layers formed on materials exposed to extracellular polymeric substances from bacterial cultures. Biofouling. 32:95-108.
Roma-Rodrigues, C, Heuer-Jungemann A, de Fernandes {MANCR}, Kanaras {AG }, Baptista {PMRV}.  2016.  Peptide-coated gold nanoparticles for modulation of angiogenesis in vivo. International journal of nanomedicine. 11:2633–2639.: Dove Medical Press Abstract

In this work, peptides designed to selectively interact with cellular receptors involved in the regulation of angiogenesis were anchored to oligo-ethylene glycol-capped gold nanoparticles (AuNPs) and used to evaluate the modulation of vascular development using an ex ovo chick chorioallantoic membrane assay. These nanoparticles alter the balance between naturally secreted pro- and antiangiogenic factors, under various biological conditions, without causing toxicity. Exposure of chorioallantoic membranes to AuNP-peptide activators of angiogenesis accelerated the formation of new arterioles when compared to scrambled peptide-coated nanoparticles. On the other hand, antiangiogenic AuNP-peptide conjugates were able to selectively inhibit angiogenesis in vivo. We demonstrated that AuNP vectorization is crucial for enhancing the effect of active peptides. Our data showed for the first time the effective control of activation or inhibition of blood vessel formation in chick embryo via AuNP-based formulations suitable for the selective modulation of angiogenesis, which is of paramount importance in applications where promotion of vascular growth is desirable (eg, wound healing) or ought to be contravened, as in cancer development.

2015
Restani, {RB }, Conde J, Pires {RF }, Martins P, Fernandes {AR}, Baptista {PV}, Bonifacio {VDB }, Aguiar-Ricardo A.  2015.  POxylated Polyurea Dendrimers: Smart Core-Shell Vectors with IC50 Lowering Capacity, aug. Macromolecular Bioscience. 15:1045–1051., Number 8: WILEY-V C H VERLAG GMBH Abstract

The design and preparation of highly efficient drug delivery platforms using green methodologies is at the forefront of nanotherapeutics research. POxylated polyurea dendrimers are efficiently synthesized using a supercritical-assisted polymerization in carbon dioxide. These fluorescent, pH-responsive and water-soluble core-shell smart nanocarriers show low toxicity in terms of cell viability and absence of glutathione depletion, two of the major side effect limitations of current vectors. The materials are also found to act as good transfection agents, through a mechanism involving an endosomal pathway, being able to reduce 100-fold the IC50 of paclitaxel.

Costa, D, Galvao AM, Di Paolo RE, Freitas AA, Lima JC, Quina FH, Macanita AL.  2015.  Photochemistry of the hemiketal form of anthocyanins and its potential role in plant protection from UV-B radiation, 2015. Tetrahedron. 71(20):3157-3162. AbstractWebsite
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Avo, J, Cidade MT, Rodriguez V, Lima JC, Parola AJ.  2015.  Photorheological Ionic Liquids, 2015. Journal of Physical Chemistry B. 119(22):6680-6685. AbstractWebsite
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Nascimento, SMC, Linhares JMM, Joao CAR, Amano K, Montagner C, Melo MJ, Vilarigues M, de Freitas MH, Alfaro C, Bailao A.  2015.  The preferred chromatic composition of unfamiliar paintings is similar to original, 2015. Perception. 44:134-134. AbstractWebsite
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Amado, MP, Ramalhete I.  2015.  Parametric Elements to Modular Social Housing, 08-2015. Architecture_MPS 2015 - ISBN 978-1-907471-69-3 . , Liverpool: Liverpool University
Greene, NG, Narciso AR, Filipe SR, Camilli A.  2015.  Peptidoglycan branched stem peptides contribute to Streptococcus pneumoniae virulence by inhibiting pneumolysin release. PLoS Pathogens. 11:e1004996.
Cerqueira, N, Gonzalez PJ, Fernandes PA, Moura JJG, Ramos MJ.  2015.  Periplasmic nitrate reductase and formate dehydrogenase: similar molecular architectures with very different enzymatic activities. Acc Chem Res. 48:2875−2884.
Grosso, AR, Leite AP, Carvalho S, Matos MR, Martins FB, Vítor AC, Desterro JM, Carmo-fonseca M, de Almeida SF.  2015.  Pervasive transcription read-through promotes aberrant expression of oncogenes and RNA chimeras in renal carcinoma. eLife. 4:e09214. AbstractWebsite

Aberrant expression of cancer genes and non-canonical RNA species is a hallmark of cancer. However, the mechanisms driving such atypical gene expression programs are incompletely understood. Here, our transcriptional profiling of a cohort of 50 primary clear cell renal cell carcinoma (ccRCC) samples from The Cancer Genome Atlas (TCGA) reveals that transcription read-through beyond the termination site is a source of transcriptome diversity in cancer cells. Amongst the genes most frequently mutated in ccRCC, we identified SETD2 inactivation as a potent enhancer of transcription read-through. We further show that invasion of neighbouring genes and generation of RNA chimeras are functional outcomes of transcription read-through. We identified the BCL2 oncogene as one of such invaded genes and detected a novel chimera, the CTSC-RAB38, in 20% of ccRCC samples. Collectively, our data highlight a novel link between transcription read-through and aberrant expression of oncogenes and chimeric transcripts that is prevalent in cancer.