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2016
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.

Mendes, MJ, Araújo A, Vicente A, Águas H, Ferreira I, Fortunato E, Martins R.  2016.  Design of optimized wave-optical spheroidal nanostructures for photonic-enhanced solar cells. Nano Energy. 26:286-296. AbstractWebsite

The interaction of light with wavelength-sized photonic nanostructures is highly promising for light management applied to thin-film photovoltaics. Several light trapping effects come into play in the wave optics regime of such structures that crucially depend on the parameters of the photonic and absorbing elements. Thus, multi-parameter optimizations employing exact numerical models, as performed in this work, are essential to determine the maximum photocurrent enhancement that can be produced in solar cells.

Generalized spheroidal geometries and high-index dielectric materials are considered here to model the design of the optical elements providing broadband absorption enhancement in planar silicon solar cells. The physical mechanisms responsible for such enhancement are schematized in a spectral diagram, providing a deeper understanding of the advantageous characteristics of the optimized geometries. The best structures, composed of TiO2 half-spheroids patterned on the cells' top surface, yield two times higher photocurrent (up to 32.5 mA/cm2 in 1.5 µm thick silicon layer) than the same devices without photonic schemes.

These results set the state-of-the-art closer to the theoretical Lambertian limit. In addition, the considered light trapping designs are not affected by the traditional compromise between absorption enhancement versus current degradation by recombination, which is a key technological advantage.

Santos, TG, Miranda RM, Vieira TM, Farinha RA, Ferreira TJ, Quintino L, Vilaça P, de Carvalho CCCR.  2016.  Developments in micro- and nano-defects detection using bacterial cells. NDT & E International. 78:20-28. AbstractWebsite

This paper describes improvements to the Nondestructive Testing (NDT) technique recently proposed, based on the use of bacterial cell suspensions to identify micro- and nano-surface defects. New bacterial strains were used with magnetic fields to improve bacteria mobility. Different materials and defect morphologies were tested, including nanoindentation defects, micro-powder injection moulding components and micro-laser welding. Nanoindentations with 0.6 µm depth and 5.3 µm side length were successfully detected. Bacterial cells allow identifying different topographic attributes of the surfaces, such as roughness. Cracks of about 0.5 µm wide and 10 µm depth in a reference test block Type 1 were successfully detected.

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
Echeverria, C, Fernandes SN, Almeida PL, Godinho MH.  2016.  Effect of cellulose nanocrystals in a cellulosic liquid crystal behaviour under low shear (regime I): Structure and molecular dynamics. European Polymer Journal. 84:675-684. AbstractWebsite

In the field of cellulosic liquid crystals, attempts to establish the relationship between structure/properties have been developed. Above a critical concentration in an aqueous solution, hydroxypropylcellulose self-assembles in order to form cholesteric liquid crystal phases (LC-HPC). In this work we aim to understand how the incorporation of a low content of cellulose nanocrystals (CNC) within LC-HPC/H2O (50 wt%), could influence the behaviour of the system when subjected to low shear rates, where the cholesteric phase still persists. The analysis of the deuterium spectrum and the T2 (transversal relaxation) values confirm that the mobility of LC-HPC at low shear rates is restricted due to CNC, and consequently so is the flow of the cholesteric polydomains. These effects are more evident in the LC-HPC sample containing 2 wt% of CNC; besides needing more strain units to induce some degree of order, the achieved degree of order is recovered faster when compared to the reference sample.

Cruz, J, Figueiredo E, Corregidor V, Girginova PI, Alves LC, Cruz C, Silva RJC, Liritzis I.  2016.  First results on radiometric dating of metals by alpha spectrometry. microchemj124-608-2016.pdf
João, CFC, Baptista AC, Ferreira IMM, Silva JC, Borges JP.  2016.  https://vtt.pure.elsevier.com/en/publications/transflexteg-large-area-transparent-thin-film-thermoelectric-devi. Fibrous and textile materials for composite applications. :261-299., Singapore: Springer Abstract

Cellulose and chitin are the two most abundant natural polysaccharides. Both have a semicrystalline microfibrillar structure from which nanofibres can be extracted. These nanofibres are rod-like microcrystals that can be used as nanoscale reinforcements in composites due to their outstanding mechanical properties. This chapter starts by reviewing the sources, extraction methods and properties of cellulose and chitin nanofibres. Then, their use in the fabrication of structural and functional nanocomposites and the applications that have been investigated are reviewed. Nanocomposites are materials with internal nano-sized structures. They benefit from the properties of the nanofillers: low density, nonabrasive, nontoxic, low cost, susceptibility to chemical modifications and biodegradability. Diverse manufacturing technologies have been used to produce films, fibres, foams, sponges, aerogels, etc. Given their natural origin and high stiffness, these polymers have attracted a lot of attention not only in the biomedical and tissue engineering fields but also in areas such as pharmaceutics, cosmetics, agriculture, biosensors and water treatment.

Gravato-Nobre, MJ, Vaz F, Filipe S, Chalmers R, Hodgkin J.  2016.  The invertebrate lysozyme effector ILYS-3 is systemically activated in response to danger signals and confers antimicrobial protection in C. elegans. PLoS Pathogens. 15:e1005826.
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.

Corvo, L, Mendo AS, Figueiredo S, Larguinho M, Gaspar R, Baptista PV, Fernandes AR.  2016.  Liposomes as delivery system of a Sn(IV) compound for cancer therapy. Pharmaceutical Research. 6(33):1351-8. AbstractWebsite

PROPOSE:
Tin complexes demonstrate antiproliferative activities in some case higher than cisplatin, with IC50 at the low micromolar range. We have previously showed that the cyclic trinuclear complex of Sn(IV) bearing an aromatic oximehydroxamic acid group [nBu2Sn(L)]3 (L=N,2-dihydroxy-5-[N-hydroxyethanimidoyl]benzamide) (MG85) shows high anti-proliferative activity, induces apoptosis and oxidative stress, and causes destabilization of tubulin microtubules, particularly in colorectal carcinoma cells. Despite the great efficacy towards cancer cells, this complex still shows some cytotoxicity to healthy cells. Targeted delivery of this complex specifically towards cancer cells might foster cancer treatment.
METHODS:
MG85 complex was encapsulated into liposomal formulation with and without an active targeting moiety and cancer and healthy cells cytotoxicity was evaluated.
RESULTS:
Encapsulation of MG85 complex in targeting PEGylated liposomes enhanced colorectal carcinoma (HCT116) cancer cell death when compared to free complex, whilst decreasing cytotoxicity in non-tumor cells. Labeling of liposomes with Rhodamine allowed assessing internalization in cells, which showed significant cell uptake after 6 h of incubation. Cetuximab was used as targeting moiety in the PEGylated liposomes that displayed higher internalization rate in HCT116 cells when compared with non-targeted liposomes, which seems to internalize via active binding of Cetuximab to cells.
CONCLUSIONS:
The proposed formulation open new avenues in the design of innovative transition metal-based vectorization systems that may be further extended to other novel metal complexes towards the improvement of their anti-cancer efficacy, which is usually hampered by solubility issues and/or toxicity to healthy tissues.

João, C, Baptista AC, Ferreira I, Silva JC, Borges JP.  2016.  Natural Nanofibres for Composite Applications. Fibrous and Textile Materials for Composite Applications. (Sohel Rana, Raul Fangueiro, Eds.).:261-299., Singapore: Springer Singapore Abstract

Cellulose and chitin are the two most abundant natural polysaccharides. Both have a semicrystalline microfibrillar structure from which nanofibres can be extracted. These nanofibres are rod-like microcrystals that can be used as nanoscale reinforcements in composites due to their outstanding mechanical properties. This chapter starts by reviewing the sources, extraction methods and properties of cellulose and chitin nanofibres. Then, their use in the fabrication of structural and functional nanocomposites and the applications that have been investigated are reviewed. Nanocomposites are materials with internal nano-sized structures. They benefit from the properties of the nanofillers: low density, nonabrasive, nontoxic, low cost, susceptibility to chemical modifications and biodegradability. Diverse manufacturing technologies have been used to produce films, fibres, foams, sponges, aerogels, etc. Given their natural origin and high stiffness, these polymers have attracted a lot of attention not only in the biomedical and tissue engineering fields but also in areas such as pharmaceutics, cosmetics, agriculture, biosensors and water treatment.

Fundo, JF, Galvis-Sanchez A, Madureira AR, Carvalho A, Feio G, Silva CLM, Quintas MAC.  2016.  NMR water transverse relaxation time approach to understand storage stability of fresh-cut ‘Rocha’pear. LWT-Food Science and Technology. 74:280-285. AbstractWebsite

Fresh-cut fruit is an important segment in fruit market due to the increasing demand for healthy/convenient foods. However, processing promotes a decrease in fruits stability with faster physiological and microbiological deteriorations. Food stability is strongly attributed to its molecular dynamics and “water availability”. Understanding changes in water location/mobility is of utmost importance, since water dynamics profoundly influences physic-chemical and microbiological quality of foods. Nuclear magnetic resonance spectroscopy (NMR) is a methodology used to study the food constituents' molecular dynamics.

The aim of this study is to use NMR to evaluate changes in water mobility that occurred in fresh-cut pear tissues during storage, by measuring the transverse relaxation time (T2) parameter.

Results showed the existence of three water classes in the cells after processing, with T2 values of 10 ms, 187 ms and 3s for cellular wall, cytoplasm and vacuole, respectively. Also, the obtained results demonstrated that T2 was affected by processing and storage. Moreover, a relationship between T2, microstructure and the quality parameters was established. T2, maximum value increased with pear hardness as well as water activity. On the contrary, a decrease in total colour difference (TCD) was found with T2.

Results demonstrate the usefulness of the application of NMR relaxometry in food studies.

Mendes, R, Carreira B, Baptista PV, Fernandes AR.  2016.  Non-small lung cancer biomarkers and targeted therapy - two faces of the same coin fostered by Nanotechnology. Expert Review of Precision Medicine and Drug Development. 1(2):155-168. AbstractWebsite

Lung cancer is the leading cause of cancer-related mortality in the world, non-small lung cancer (NSCLC) is the most frequent subtype (85% of the cases). Within this subtype, adenocarcinoma and squamous cell carcinoma are the most frequent. New therapeutic strategies based on targeted delivery of drugs have relied on the use of biomarkers derived from the patients’ molecular profiling. Several biomarkers have been found to be useful for use as targets for precision therapy in NSCLC, such as mutations in the epidermal growth factor receptor, v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog, anaplastic lymphoma kinase, mesenchymal-epithelial transition factor receptor tyrosine kinase, BRAF, c-ros oncogene 1, P53 and phosphatase with tensin homology. Current developments in Nanomedicine have allowed for multifunctional systems capable of delivering therapeutics with increased precision to the target site/tissue, while simultaneously assisting in diagnosis. Here, we review the use of biomarkers in nanotechnology translation in NSCLC management.

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.

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.
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
Maia, LB, Fonseca L, Moura I, Moura JJG.  2016.  Reduction of carbon dioxide by a molybdenum-containing formate dehydrogenase: a kinetic and mechanistic study. J Am Chem Soc. 138:8834-8846.Website
Fernandes, CSM, Barbosa I, Castro R, Pina AS, Coroadinha AS, Barbas A, Roque ACA.  2016.  Retroviral particles are effectively purified on an affinity matrix containing peptides selected by phage-display. Biotechnology Journal. 11:1513–1524. Abstract

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Carvalho, R, Almeida R, Moura JJG, Lourenço N, Fonseca L, Cordas CM.  2016.  Sandwich-Type Enzymatic Fuel Cell Based on a New Electro-Conductive Material - Ion Jelly. Chemistry Select. 1:6546–6552.Website
Silva, M, Silva Z, Marques G, Ferro T, Gonçalves M, Monteiro M, van Vliet SJ, Mohr E, Lino AC, Fernandes AR, Lima FA, van Kooyk Y, Matos T, Tadokoro CE, Videira PA.  2016.  Sialic acid removal from dendritic cells improves antigen cross-presentation and boosts anti-tumor immune responses. Oncotarget . AbstractWebsite

Dendritic cells (DCs) hold promise for anti-cancer immunotherapy. However, clinically, their efficiency is limited and novel strategies to improve DC-mediated anti-tumor responses are needed. Human DCs display high content of sialic acids, which inhibits their maturation and co-stimulation capacity. Here, we aimed to understand whether exogenous desialylation of DCs improves their anti-tumor immunity. Compared to fully sialylated DCs, desialylated human DCs loaded with tumor-antigens showed enhanced ability to induce autologous T cells to proliferate, to secrete Th1 cytokines, and to specifically induce tumor cell apoptosis. Desialylated DCs showed an increased expression of MHC-I and -II, co-stimulatory molecules and an augmented secretion of IL-12. Desialylated HLA-A*02:01 DCs pulsed with gp100 peptides displayed enhanced peptide presentation through MHC-I, resulting in higher activation ofgp100280–288 specific CD8+ cytotoxic T cells. Desialylated murine DCs also exhibited increased MHC and co-stimulatory molecules and higher antigen cross-presentation via MHC-I. These DCs showed higher ability to activate antigen-specific CD4+ and CD8+ T cells, and to specifically induce tumor cell apoptosis. Collectively, our data demonstrates that desialylation improves DCs’ ability to elicit T cell-mediated anti-tumor activity, due to increased MHC-I expression and higher antigen presentation via MHC-I. Sialidase treatment of DCs may represent a technology to improve the efficacy of antigen loaded-DC-based vaccines for anti-cancer immunotherapy.

Fernandes, CSM, Castro R, Coroadinha AS, Roque ACA.  2016.  Small synthetic ligands for the enrichment of viral particles pseudotyped with amphotropic murine leukemia virus envelope. Journal of Chromatography A. 1438:160–170.: Elsevier B.V. AbstractWebsite

Retroviral vectors gained popularity toward other viral vectors as they integrate their genome into hosts' genome, a characteristic required for the modification of stem cells. However, the production of viable particles for gene therapy is hampered by the low ratio of infectious to non-infectious viral particles after purification, low titers and limited number of competent viral receptors. We have developed de novo two fully synthetic triazine-based ligands that can selectively bind retroviral particles pseudotyped with amphotropic murine leukemia virus envelope (AMPHO4070A). A 78-membered library of triazine-based ligands was designed in silico and was virtually screened against the modeled structure of the AMPHO4070A protein. Ligands displaying the highest energy of binding were synthesized on cross-linked agarose and experimentally tested. Adsorbents containing ligands A5A10 and A10A11 showed selectivity toward viral particles containing the target protein (VLP-AMPHO), binding 19 ± 5 $μ$g/g support and 47 ± 13 $μ$g/g support, respectively. The elution conditions for both ligands were mild and with high recovery yields (80-100{%}), in comparison with common purification practices. These results were based on a lab-scale experimental setting with VLP integrity being confirmed through TEM. In particular, the elution buffer containing 12 mM imidazole allowed the recovery of intact amphotropic viral particles.

Santos, L, Silveira CM, Elangovan E, Neto JP, Nunes D, Pereira L, Martins R, Viegas J, Moura JJG, Todorovic S, Almeida MG, Fortunato EM.  2016.  Synthesis of WO3 nanoparticles for biosensing applications. Sensors and Actuators B: Chemical. 223:186-194.
Ma, Z, Zhang B, da Silva FGMC, Mendo AS, Silva J, Baptista PV, Fernandes AR, Pombeiro AJL.  2016.  Synthesis, Characterization, Thermal Properties and Antiproliferative Potential of Copper(II) 4′-phenyl-terpyridine Compounds. Dalton Transations. (12) AbstractWebsite

Reactions between 4′-phenyl-terpyridine (L) and several Cu(II) salts (p-toluenesulfonate, benzoate and o-, m- or p-hydroxybenzoate) led to the formation of [Cu(p-SO3C6H4CH3)L(H2O)2](p-SO3C6H4CH3) (1), [Cu(OCOPh)2L] (2), [Cu(o-OCOC6H4OH)2L] (3), [Cu(m-OCOC6H4OH)2L]·MeOH (4·MeOH) and [Cu(p-OCOC6H4OH)2L]·2H2O (5·2H2O), which were characterized by elemental and TG-DTA analyses, ESI-MS, IR spectroscopy and single crystal X-ray diffraction, as well as by conductivimetry. In all structures the Cu atoms present N3O3 octahedral coordination geometries, which, in 2–5, are highly distorted as a result of the chelating-bidentate mode of one of the carboxylate ligands. Intermolecular π⋯π stacking interactions could also be found in 2–5 (in the 3.569–3.651 Å range and involving solely the pyridyl rings). Medium–strong hydrogen bond interactions lead to infinite 1D chains (in 1 and 4) and to an infinite 2D network (in 5). Compounds 1 and 4 show high in vitro cytotoxicity towards HCT116 colorectal carcinoma and HepG2 hepatocellular carcinoma cell lines. The antiproliferative potential of compound 1 is due to an increase of the apoptotic process that was confirmed by Hoechst staining, flow cytometry and RT-qPCR. All compounds able to non-covalently intercalate the DNA helix and induce in vitro pDNA double-strand breaks in the absence of H2O2. Concerning compound 1, the hydroxyl radical and singlet oxygen do not appear to be involved in the pDNA cleavage process and the fact that this cleavage also occurs in the absence of molecular oxygen points to a hydrolytic mechanism of cleavage.

Muñoz-ruiz, M, Ribot JC, Grosso AR, Gonçalves-sousa N, Pamplona A, Pennington DJ, Regueiro JR, Fernández-malavé E, Silva-santos B.  2016.  TCR signal strength controls thymic differentiation of discrete proinflammatory γδT cell subsets. Nature immunology. , Number April AbstractWebsite

The mouse thymus produces discrete γδ T cell subsets that make either interferon-γ (IFN-γ) or interleukin 17 (IL-17), but the role of the T cell antigen receptor (TCR) in this developmental process remains controversial. Here we show that Cd3g(+/-) Cd3d(+/-) (CD3 double-haploinsufficient (CD3DH)) mice have reduced TCR expression and signaling strength on γδ T cells. CD3DH mice had normal numbers and phenotypes of αβ thymocyte subsets, but impaired differentiation of fetal Vγ6(+) (but not Vγ4(+)) IL-17-producing γδ T cells and a marked depletion of IFN-γ-producing CD122(+) NK1.1(+) γδ T cells throughout ontogeny. Adult CD3DH mice showed reduced peripheral IFN-γ(+) γδ T cells and were resistant to experimental cerebral malaria. Thus, TCR signal strength within specific thymic developmental windows is a major determinant of the generation of proinflammatory γδ T cell subsets and their impact on pathophysiology.