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2013
Lanca, T, Costa MF, Goncalves-Sousa N, Rei M, Grosso AR, Penido C, Silva-Santos B.  2013.  Protective role of the inflammatory CCR2/CCL2 chemokine pathway through recruitment of type 1 cytotoxic γδ T lymphocytes to tumor beds. J Immunol. 190:6673–6680., Number 12 AbstractWebsite

Tumor-infiltrating lymphocytes (TILs) are important prognostic factors in cancer progression and key players in cancer immunotherapy. Although γδ T lymphocytes can target a diversity of tumor cell types, their clinical manipulation is hampered by our limited knowledge of the molecular cues that determine γδ T cell migration toward tumors in vivo. In this study we set out to identify the chemotactic signals that orchestrate tumor infiltration by γδ T cells. We have used the preclinical transplantable B16 melanoma model to profile chemokines in tumor lesions and assess their impact on γδ TIL recruitment in vivo. We show that the inflammatory chemokine CCL2 and its receptor CCR2 are necessary for the accumulation of γδ TILs in B16 lesions, where they produce IFN-γ and display potent cytotoxic functions. Moreover, CCL2 directed γδ T cell migration in vitro toward tumor extracts, which was abrogated by anti-CCL2 neutralizing Abs. Strikingly, the lack of γδ TILs in TCRδ-deficient but also in CCR2-deficient mice enhanced tumor growth in vivo, thus revealing an unanticipated protective role for CCR2/CCL2 through the recruitment of γδ T cells. Importantly, we demonstrate that human Vδ1 T cells, but not their Vδ2 counterparts, express CCR2 and migrate to CCL2, whose expression is strongly deregulated in multiple human tumors of diverse origin, such as lung, prostate, liver, or breast cancer. This work identifies a novel protective role for CCL2/CCR2 in the tumor microenvironment, while opening new perspectives for modulation of human Vδ1 T cells in cancer immunotherapy.

Maiti, BK, Avilés T, Carepo MS, Moura I, S.R. P, Moura JJG.  2013.  Rearrangement of Mo-Cu-S Cluster Reflects the Structural Instability of Orange Protein Cofactor. Z Anorg Allg Chem. 639:1361-1364.
Martins, Ahnood, Arman, Correia, Nuno, Pereira, Barros, R., Barquinha, Costa, Ferreira, Nathan, Arokia, Fortunato E.  2013.  Recyclable, Flexible, Low-Power Oxide Electronics. Advanced Functional Materials. 23(17):2153-2161.
Dudognon, E, Correia NT, Danède F, Descamps M.  2013.  Solid-Solid Transformation in Racemic Ibuprofen. Pharmaceutical Research. 30(1):81-89.
Cerqueira, N, Fernandes P, González P, Moura JJG, Ramos MJ.  2013.  The sulfur-shift: an activation mechanism for periplasmic nitrate reductase and formate dehydrogenase. Inorg Chem. 52:10766-10772.
Caires, L, Seco JC.  2013.  The Type Discipline of Behavioral Separation. Proceedings of the 40th Symposium on Principles of Programming Languages (POPL). Abstract

We introduce the concept of behavioral separation as a general prin- ciple for disciplining interference in higher-order imperative con- current programs, and present a type-based approach that system- atically develops the concept in the context of an ML-like language extended with concurrency and synchronization primitives. Behav- ioral separation builds on notions originally introduced for behav- ioral type systems and separation logics, but shifts the focus from the separation of static program state properties towards the sep- aration of dynamic usage behaviors of runtime values. Behavioral separation types specify how values may be safely used by client code, and can enforce fine-grained interference control disciplines while preserving compositionality, information hiding, and flexi- bility. We illustrate how our type system, even if based on a small set of general primitives, is already able to tackle fairly challenging program idioms, involving aliasing at various types, concurrency with first-class threads, manipulation of linked data structures, be- havioral borrowing, and invariant-based separation.

Baltazar, LG, Henriques FMA, Jorne F, Cidade MT.  2013.  The use of rheology in the study of the composition effects on the fresh behaviour of hydraulic lime grouts for injection of masonry walls. Rheologica Acta . 52(2):127-138.
Daniel, CI, Chavez FV, Feio G, Portugal CA, Crespo JG, Sebastiao PJ.  2013.  1H NMR relaxometry, viscometry, and PFG NMR studies of magnetic and nonmagnetic ionic liquids. J Phys Chem B. 117:11877-84., Number 39 AbstractWebsite

A study is presented of the molecular dynamics and of the viscosity in pure [Aliquat][Cl] ionic liquid and in a mixture of [Aliquat][Cl] with 1% (v/v) of [Aliquat][FeCl4]. The (1)H spin-lattice relaxation rate, R1, was measured by NMR relaxometry between 8 and 300 MHz. In addition, the translation self-diffusion, D, was measured by pulse field gradient NMR. The ILs' viscosity was measured as a function of an applied magnetic field, B, and it was found that the IL mixture's viscosity decreased with increasing B, whereas the [Aliquat][Cl] viscosity is independent of B. All experimental results were analyzed taking into account the viscosity's magnetic field dependence, assuming a modified Stokes-Einstein diffusion/viscosity relation. The main difference between the relaxation mechanisms responsible for R1 in the two IL systems is related to the additional paramagnetic relaxation contribution associated with the (1)H spins-[FeCl4] paramagnetic moments' interactions. Cross-relaxation cusps in the R1 dispersion, associated with (35)Cl and (1)H nuclear spins in the IL systems, were detected. The R1 model considered was successfully fitted to the experimental results, and it was possible to estimate the value of D at zero field in the case of the IL mixture which was consistent with the values of D measured at 7 and 14.1 T and with the magnetic field dependence estimated from the viscosity measurements. It was observed that a small concentration of [Aliquat][FeCl4] in the [Aliquat][Cl] was enough to produce a "superparamagnetic"-like effect and to change the IL mixture's molecular dynamics and viscosity and to allow for their control with an external magnetic field.

Cruz, C, Santos SD, Cabrita EJ, Queiroz JA.  2013.  Binding analysis between l-histidine immobilized and oligonucleotides by SPR and NMR. International Journal of Biological Macromolecules. 56:175-180. Abstract

Saturation transfer difference (STD) NMR technique and surface plasmon resonance (SPR) are used to study amino acid affinity supports–nucleotides interactions with l-histidine amino acid immobilized on a surface as model support. We have immobilized l-histidine ligand on a carboxymethyldextran- modified gold surface intended for surface plasmon resonance and we analyze the binding profiles of synthetic polynucleotides (1–6 base, sugar and backbone) by determining the equilibrium dissociation constant (KD). The SPR binding profile (square-shaped) is identical for all the complexes and the highest binding affinity can be found for polyA6 followed by polyG6 . As expected, the 5′ -mononucleotides have the lowest affinity. To further study the structural aspects of the interaction we investigate the polynucleotide binding preferences to l-histidine chromatography support by STD-NMR spectroscopy. These results revealed that an increase in the number of bases and backbone to 6 units leads to more contacts with the support, where the main driving force for the interaction with polynucleotides are through the base, except for polyC6 , which is mainly through sugar-phosphate backbone. Therefore, the combination of SPR measurements with STD-NMR technique allowed to establish fine details of the molecular recognition process involved in amino acid affinity supports–nucleotides complexes.

Seixas, JD, Mukhopadhyay A, Santos-Silva T, Otterbein LE, Gallo DJ, Rodrigues SS, Guerreiro BH, Goncalves AML, Penacho N, Marques AR, Coelho AC, Reis PM, Romao MJ, Romao CC.  2013.  Characterization of a versatile organometallic pro-drug (CORM) for experimental CO based therapeutics. Dalton Transactions. 42:5985-5998., Number 17 AbstractWebsite
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Pedrosa, P, Veigas B, Machado D, Perdigão J, Portugal I, Couto I, Viveiros M, Baptista {PV}.  2013.  Detec{\c c}ão de MDRTB por gold-nanoprobes – uma nova abordagem tecnológica desenvolvida em Portugal. Abstract
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Mukhopadhyay, A, Bursakov SA, Ramos JL, Wittich RM, Kladova AV, Romao MJ, van Dillewijn P, Carvalho AL.  2013.  Determinants of selective group reduction in the TNT-bound xenobiotic reductase B from P. putida. European Biophysics Journal with Biophysics Letters. 42:S179-S179. AbstractWebsite
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Neves, CS, Granadeiro CM, Cunha-Silva L, Ananias D, Gago S, Feio G, Carvalho PA, Eaton P, Balula SS, Pereira E.  2013.  Europium Polyoxometalates Encapsulated in Silica Nanoparticles Characterization and Photoluminescence Studies. European Journal of Inorganic Chemistry. :2877-2886., Number 16 AbstractWebsite
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Neves, CS, Granadeiro CM, Cunha-Silva L, Ananias D, Gago S, Feio G, Carvalho PA, Eaton P, Balula SS, Pereira E.  2013.  Europium Polyoxometalates Encapsulated in Silica Nanoparticles Characterization and Photoluminescence Studies. European Journal of Inorganic Chemistry. :2877-2886., Number 16 AbstractWebsite

The incorporation of europium polyoxometalates into silica nanoparticles can lead to a biocompatible nanomaterial with luminescent properties suitable for applications in biosensors, biological probes, and imaging. Keggin-type europium polyoxometalates Eu(PW11)x (x = 1 and 2) with different europium coordination environments were prepared by using simple methodologies and no expensive reactants. These luminescent compounds were then encapsulated into silica nanoparticles for the first time through the water-in-oil microemulsion methodology with a nonionic surfactant. The europium polyoxometalates and the nanoparticles were characterized by using several techniques [FTIR, FT-Raman, 31P magic angle spinning (MAS) NMR, and TEM/energy-dispersive X-ray spectroscopy (TEM-EDS), AFM, dynamic light scattering (DLS), and inductively coupled plasma MS (ICP-MS) analysis]. The stability of the material and the integrity of the europium compounds incorporated were also examined. Furthermore, the photoluminescence properties of the Eu(PW11)x@SiO2 nanomaterials were evaluated and compared with those of the free europium polyoxometalates. The silica surface of the most stable nanoparticles was successfully functionalized with appropriate organosilanes to enable the covalent binding of oligonucleotides.

Pereira, CCL, Dias S, Coutinho I, Leal JP, Branco LC, Laia CAT.  2013.  Europium(III) Tetrakis(beta-diketonate) Complex as an Ionic Liquid: A Calorimetric and Spectroscopic Study. Inorganic Chemistry. 52:3755-3764., Number 7 AbstractWebsite
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Gawande, MB, Guo H, Rathi AK, Branco PS, Chen Y, Varma RS, Peng D-L.  2013.  First application of core-shell Ag@Ni magnetic nanocatalyst for transfer hydrogenation reactions of aromatic nitro and carbonyl compounds. RSC ADVANCES. 3:1050-1054., Number 4 Abstract
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Oliveira, FS, Pereiro AB, Araujo JM, Bernardes CE, Canongia Lopes JN, Todorovic S, Feio G, Almeida PL, Rebelo LP, Marrucho IM.  2013.  High ionicity ionic liquids (HIILs): comparing the effect of ethylsulfonate and ethylsulfate anions. Phys Chem Chem Phys. 15:18138-47., Number 41 AbstractWebsite

The subject of ionicity has been extensively discussed in the last decade, due to the importance of understanding the thermodynamic and thermophysical behaviour of ionic liquids. In our previous work, we established that ionic liquids' ionicity could be improved by the dissolution of simple inorganic salts in their milieu. In this work, a comparison between the thermophysical properties of two binary systems of ionic liquid + inorganic salt is presented. The effect of the ammonium thiocyanate salt on the ionicity of two similar ionic liquids, 1-ethyl-3-methylimidazolium ethylsulfonate and ethylsulfate, is investigated in terms of the related thermophysical properties, such as density, viscosity and ionic conductivity in the temperature range 298.15-323.15 K. In addition, spectroscopic (NMR and Raman) and molecular dynamic studies were conducted in order to better understand the interactions that occur at a molecular level. The obtained results reveal that although the two anions of the ionic liquid exhibit similar chemical structures, the presence of one additional oxygen in the ethylsulfate anion has a major impact on the thermophysical properties of the studied systems.

Mahro, M, Bras NF, Cerqueira NMFSA, Teutloff C, Coelho C, Romao MJ, Leimkuehler S.  2013.  Identification of Crucial Amino Acids in Mouse Aldehyde Oxidase 3 That Determine Substrate Specificity. Plos One. 8, Number 12 AbstractWebsite
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Coelho, C, Marangon J, Rodrigues D, Moura JJG, Romao MJ, Paes de Sousa PM, Correia dos Santos MM.  2013.  Induced peroxidase activity of haem containing nitrate reductases revealed by protein film electrochemistry. Journal of Electroanalytical Chemistry. 693:105-113. AbstractWebsite
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Gomes, L, Marques A, Branco A, Araujo J, Simoes M, Cardoso S, Silva F, Henriques I, Laia CAT, Costa C.  2013.  IZO deposition by RF and DC sputtering on paper and application on flexible electrochromic devices. Displays. 34:326-333., Number 4 AbstractWebsite
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Marangon, J, Correia HD, Brondino CD, Moura JJG, Romao MJ, Gonzalez PJ, Santos-Silva T.  2013.  Kinetic and Structural Studies of Aldehyde Oxidoreductase from Desulfovibrio gigas Reveal a Dithiolene-Based Chemistry for Enzyme Activation and Inhibition by H2O2. Plos One. 8, Number 12 AbstractWebsite
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Conde, J, {de la Fuente} {JM }, Baptista {PV}.  2013.  Nanomaterials for reversion of multidrug resistance in cancer: a new hope for an old idea? Frontiers in Pharmacology. 4: Frontiers Media Abstract
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Kasthurirangan, S, Saha JK, Agnihotri AN, Bhattacharyya S, Misra D, Kumar A, Mukherjee PK, Santos JP, Costa AM, Indelicato P, Mukherjee TK, Tribedi LC.  2013.  Observation of 2p3 d (1Po)→ 1s3d (1De) Radiative Transition in He-like Si, S, and Cl Ions. Physical Review Letters. 111:243201. AbstractWebsite
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Verma, AK, Goyal A, Freire F, Bule P, Venditto I, Bras JLA, Santos H, Cardoso V, Bonifacio C, Thompson A, Romao MJ, Prates JAM, Ferreira LMA, Fontes CMGA, Najmudin S.  2013.  Overexpression, crystallization and preliminary X-ray crystallographic analysis of glucuronoxylan xylanohydrolase (Xyn30A) from Clostridium thermocellum. Acta Crystallographica Section F-Structural Biology and Crystallization Communications. 69:1440-1442. AbstractWebsite
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Figueiredo, AM, Sardinha J, Moore GR, Cabrita EJ.  2013.  Protein destabilisation in ionic liquids: the role of preferential interactions in denaturation. Phys. Chem. Chem. Phys.. (15):19632-19643. Abstract

The preferential binding of anions and cations in aqueous solutions of the ionic liquids (ILs) 1-butyl- 3-methylimidazolium ([C4mim]+) and 1-ethyl-3-methylimidazolium ([C2mim]+) chloride and dicyanamide (dca-) with the small alpha-helical protein Im7 was investigated using a combination of differential scanning calorimetry, NMR spectroscopy and molecular dynamics (MD) simulations. Our results show that direct ion interactions are crucial to understand the effects of ILs on the stability of proteins and that an anion effect is dominant. We show that the binding of weakly hydrated anions to positively charged or polar residues leads to the partial dehydration of the backbone groups, and is critical to control stability, explaining why dca- is more denaturing than Cl-. Direct cation–protein interactions also mediate stability; cation size and hydrophobicity are relevant to account for destabilisation as shown by the effect of [C4mim]+ compared to [C2mim]+. The specificity in the interaction of IL ions with protein residues established by weak favourable interactions is confirmed by NMR chemical shift perturbation, amide hydrogen exchange data and MD simulations. Differences in specificity are due to the balance of interaction established between ion pairs and ion-solvent that determine the type of residues affected. When the interaction of both cation and anion with the protein is strong the net result is similar to a non-specific interaction, leading ultimately to unfolding. Since the nature of the ions is a determinant of the level of interaction with the protein towards denaturation or stabilisation, ILs offer a unique possibility to modulate protein stabilisation or even folding events.