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2015
Basilio, N; Cabrita, PL; F.  2015.  Mimicking Positive and Negative Copigmentation Effects in Anthocyanin Analogues by Host-Guest Interaction with Cucurbit[7]uril and beta-Cyclodextrins. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY. 63(35):7624-7629.
Moura, JJG, Bernhardt PV, Maia LB, Gonzalez PJ.  2015.  Molybdenum and tungsten enzymes: from biology to chemistry and back. J Biol Inorg Chem. 20:181-182.
Maia, LB, Moura JJG, Moura I.  2015.  Molybdenum and tungsten-dependent formate dehydrogenases. J Biol Inorg Chem. 20:287-309.
Poggi, F, Firmino A, Amado MP.  2015.  Moving Forward on Sustainable Energy Transitions: The Smart Rural. European Journal of Sustainable Development - DOI:10.14207/ejsd.2015.v4n2p43. 4(2):43-50.
Picado, A, Paixão SM, Moita L, Silva L, Diniz MS, Lourenço J, Peres I, Castro L, Correia JB, Pereira J, Ferreira I, Matos APA, Barquinha P, Mendonça E.  2015.  A multi-integrated approach on toxicity effects of engineered TiO2 nanoparticles. Front. Env. Sci. Eng.. 9(5):793–803. AbstractWebsite

The new properties of engineered nanoparticles drive the need for new knowledge on the safety, fate, behavior and biologic effects of these particles on organisms and ecosystems. Titanium dioxide nanoparticles have been used extensively for a wide range of applications, e.g, self-cleaning surface coatings, solar cells, water treatment agents, topical sunscreens. Within this scenario increased environmental exposure can be expected but data on the ecotoxicological evaluation of nanoparticles are still scarce. The main purpose of this work was the evaluation of effects of TiO2 nanoparticles in several organisms, covering different trophic levels, using a battery of aquatic assays. Using fish as a vertebrate model organism tissue histological and ultrastructural observations and the stress enzyme activity were also studied. TiO2 nanoparticles (Aeroxide® P25), two phase composition of anatase (65%) and rutile (35%) with an average particle size value of 27.6±11 nm were used. Results on the EC50 for the tested aquatic organisms showed toxicity for the bacteria, the algae and the crustacean, being the algae the most sensitive tested organism. The aquatic plant Lemna minor showed no effect on growth. The fish Carassius auratus showed no effect on a 21 day survival test, though at a biochemical level the cytosolic Glutathione-S-Transferase total activity, in intestines, showed a general significant decrease (p<0.05) after 14 days of exposure for all tested concentrations. The presence of TiO2 nanoparticles aggregates were observed in the intestine lumen but their internalization by intestine cells could not be confirmed.

Böhle, K, Moniz A.  2015.  No Countries for Old Technology Assessment? Sketching the Efforts and Opportunities to Establish Parliamentary TA in Spain and Portugal EconStor Open Access Articles. :29-44. AbstractWebsite

If the question is whether there is a parliamentary technology assessment (PTA) unit in Portugal or Spain, the clear answer is that there is still no such unit at the central state level at the present time, neither in Portugal nor in Spain. The question then has to be modified addressing previous and current efforts to establish PTA and the current framework conditions and opportunities. Practices of PTA are framed here as a democratic innovation in the context of changes in representative democracies. Against this backdrop, the efforts and opportunities to establish PTA in Spain and Portugal are studied. By sketching these developments and outlining the opportunities in these countries, our aim is to contribute to the debate about the likelihood of a new wave of PTA in Europe (Hennen/Nierling 2014).

Marques, AC, Santos L, Costa MN, Dantas JM, Duarte P, Gonçalves A, Martins R, Salgueiro CA, Fortunato E.  2015.  Office Paper Platform for Bioelectrochromic Detection of Electrochemically Active Bacteria using Tungsten Trioxide Nanoprobes. Sci. Rep. 5(9910) AbstractWebsite

Electrochemically active bacteria (EAB) have the capability to transfer electrons to cell exterior, a feature that is currently explored for important applications in bioremediation and biotechnology fields. However, the number of isolated and characterized EAB species is still very limited regarding their abundance in nature. Colorimetric detection has emerged recently as an attractive mean for fast identification and characterization of analytes based on the use of electrochromic materials. In this work, WO3 nanoparticles were synthesized by microwave assisted hydrothermal synthesis and used to impregnate non-treated regular office paper substrates. This allowed the production of a paper-based colorimetric sensor able to detect EAB in a simple, rapid, reliable, inexpensive and eco-friendly method. The developed platform was then tested with Geobacter sulfurreducens, as a proof of concept. G. sulfurreducens cells were detected at latent phase with an RGB ratio of 1.10 ± 0.04, and a response time of two hours.

A. C. Marques, L. Santos, M. N. Costa, J. M. Dantas, P. Duarte, A. Gonçalves, R. Martins, C. A. Salgueiro, Fortunato E.  2015.  Office Paper Platform for Bioelectrochromic Detection of Electrochemically Active Bacteria using Tungsten Trioxide Nanoprobes. Nature Publishing Group Scientific Reports. 5
Veigas, B, Pedrosa P, Carlos FF, Mancio-Silva L, Grosso AR, Fortunato E, Mota MM, Baptista PV.  2015.  One nanoprobe, two pathogens: gold nanoprobes multiplexing for point-of-care. Journal of Nanobiotechnology. 13:48., Number 1: BioMed Central AbstractWebsite

BACKGROUND:
Gold nanoparticles have been widely employed for biosensing purposes with remarkable efficacy for DNA detection. Amongst the proposed systems, colorimetric strategies based on the remarkable optical properties have provided for simple yet effective sequence discrimination with potential for molecular diagnostics at point of need. These systems may also been used for parallel detection of several targets to provide additional information on diagnostics of pathogens.
RESULTS:
For the first time, we demonstrate that a single Au-nanoprobe may provide for detection of two distinct targets (pathogens) allowing colorimetric multi-target detection. We demonstrate this concept by using one single gold-nanoprobe capable to detect members of the Mycobacterium tuberculosis complex and Plasmodium sp., the etiologic agents of tuberculosis and malaria, respectively. Following characterisation, the developed gold-nanoprobe allowed detection of either target in individual samples or in samples containing both DNA species with the same efficacy.
CONCLUSIONS:
Using one single probe via the non-cross-linking colorimetric methodology it is possible to identify multiple targets in one sample in one reaction. This proof-of-concept approach may easily be integrated into sensing platforms allowing for fast and simple multiplexing of Au-nanoprobe based detection at point-of-need.

Echeverria, C, Soares PIP, Robalo A, Pereira L, Novo C, Ferreira I, Borges JP.  2015.  One-pot synthesis of dual-stimuli responsive hybrid PNIPAAm-chitosan microgels. Materials & Design. 86:745-751. AbstractWebsite

The incorporation of magnetic nanoparticles into poly(N-isopropylacrylamide) (PNIPAAm) and chitosan microgels gives rise to hybrid systems that combine the microgels swelling capacity with the interesting features presented in magnetic nanoparticles. The presence of chitosan that act as surfactant for magnetic nanoparticles provides a simplistic approach which allows the encapsulation of magnetic nanoparticles without any previous surface modification. Spherical and highly monodisperse microgels with diameters in the range of 200 to 500 nm were obtained. The encapsulation of magnetic nanoparticles in the polymer matrix was confirmed by high resolution Scanning Electron Microscopy in transmission mode. Volume phase transition of the microgels was accessed by Dynamic Light Scattering measurements. It was observed that the thermosensitivity of the PNIPAM microgels still persists in the hybrid microgels; however, the swelling ability is compromised in the microgels with highest chitosan content. The heating performance of the hybrid magnetic microgels, when submitted to an alternating magnetic field, was also evaluated demonstrating the potential of these systems for hyperthermia treatments.

Echeverria, C, Soares P, Robalo A, Pereira L, Novo CMM, Ferreira I, Borges JP.  2015.  One-pot synthesis of dual-stimuli responsive hybrid PNIPAAm-chitosan microgels. Mater. Des. 86:745-751. AbstractWebsite

The incorporation of magnetic nanoparticles into poly(N-isopropylacrylamide) (PNIPAAm) and chitosan microgels gives rise to hybrid systems that combine the microgels swelling capacity with the interesting features presented in magnetic nanoparticles. The presence of chitosan that act as surfactant for magnetic nanoparticles provides a simplistic approach which allows the encapsulation of magnetic nanoparticles without any previous surface modification. Spherical and highly monodisperse microgels with diameters in the range of 200 to 500 nm were obtained. The encapsulation of magnetic nanoparticles in the polymer matrix was confirmed by high resolution Scanning Electron Microscopy in transmission mode. Volume phase transition of the microgels was accessed by Dynamic Light Scattering measurements. It was observed that the thermosensitivity of the PNIPAM microgels still persists in the hybrid microgels; however, the swelling ability is compromised in the microgels with highest chitosan content. The heating performance of the hybrid magnetic microgels, when submitted to an alternating magnetic field, was also evaluated demonstrating the potential of these systems for hyperthermia treatments.

Rodrigues, L. C., Mata, D., Pimentel, Nunes, D., Martins, Fortunato, Neves, Nuno, Monteiro, T., Costa FM.  2015.  One-step synthesis of ZnO decorated CNT buckypaper composites and their optical and electrical properties. Materials Science and Engineering: B. 195:38-44.
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.

Vilarigues, M, Machado A.  2015.  Pintar com luz: o esmalte azul na pintura de vitral. Química – Boletim da Sociedade Portuguesa de Química. :137.
Amado, MP, Poggi F.  2015.  Planning PV power plants in sub-Saharan African countries. The case of Fogo Island – Cabo Verde. Materials and technologies for energy efficiency. (Antonio Méndez-Vilas, Ed.).:286., London, UK: BrownWalker Pres, ISBN-13: 978-1-62734-559-0
Restani, RB, Conde J, Pires RF, Martins P, Fernandes AR, Baptista PV, Bonifácio VDB, Aguiar-Ricardo A.  2015.  POxylated polyurea dendrimers: Smart core-shell vectors with IC50 lowering capacity. Macromol. Biosci.. AbstractWebsite

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.

Cavique, M, Flores J, Amado MP, Gonçalves-Coelho A, Mourão A.  2015.  A preliminary check of the refurbishing large office buildings to a zero energy condition. Procedia CIRP. 34(DOI: 10.1016/j.procir.2015.07.054):193-198.
Mano, F, Aroso I, Barreiros S, Borges JP, Reis R, Duarte AR, Paiva A.  2015.  Production of Poly(vinyl alcohol) (PVA) Fibers with Encapsulated Natural Deep Eutectic Solvent (NADES) Using Electrospinning. ACS Sustainable Chemistry & Engineering. 3(10):2504–2509. AbstractWebsite

Functionalized electrospun fibers are of great interest for biomedical applications such as in the design of drug delivery systems. Nevertheless, in some cases the molecules of interest have poor solubility in water or have high melting temperatures. These drawbacks can be overcome using deep eutectic solvents. In this work, poly(vinyl alcohol) (PVA), a common biodegradable biopolymer, was used to produce new functionalized fibers with the eutectic mixture choline chloride:citric acid in a molar ratio of (1:1) ChCl:CA (1:1), which was used as a model system. Fibers were produced from an aqueous solution with 7.8% (w/v) and 9.8% (w/v) of 95% hydrolyzed PVA and a 2% (v/v) of ChCl:CA (1:1). Smooth, uniform fibers with an average diameter of 0.4 μm were obtained with a content of 19.8 wt % of ChCl:CA (1:1) encapsulated.

Johnston, EM, Dell'Acqua S, Pauleta SR, Moura I, Solomon EI.  2015.  Protonation state of the Cu4S2 CuZ site in nitrous oxide reductase: redox dependence and insight into reactivity. Chem Sci. 6:5670-5679.