ICI - Instituto Coordenador da Investigação
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O ICI integra Unidades de Investigação que exerçam as suas atividades na UBI e que tenham sido classificados com notação igual ou superior a Bom pelos painéis internacionais de avaliação periódica designados pela Fundação para a Ciência e Tecnologia.
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- 17 Beta-Estradiol and progesterone inhibit L-type Ca2+ current of rat aorta smooth muscle cellsPublication . Verde, Ignacio; Cairrão, Elisa; Carvas, João; Silva, António José Santos; Alvarez, EzequielSex hormones like 17ß-estradiol (ßES) and progesterone have shown rapid non-genomic vasodilator effects, which could be involved in the protection of cardiovascular system. However, the precise mechanism by which this effect occurs has not been elucidated yet, even if Ca2+ influx inhibition seems to be implicated. The aim of this study was to study the influence of ßES and progesterone on the L-type Ca2+ current measured by whole cell voltage-clamp in A7r5 cells. Voltage-operated Ca2+ currents were elicited by square-step voltage pulses and pharmacologically characterized as L-type currents by (-)-Bay K8644 (BAY) and nifedipine. Both ßES and progesterone (1-100 µM), rapidly and reversibly inhibited, in a concentration dependent manner, either non-stimulated or BAY-stimulated Ca2+ currents registered in A7r5 cells. These results suggest that ßES and progesterone inhibit L-type voltage-operated Ca2+ channels through a non-genomic pathway. Consequently, these hormones inhibit the Ca2+ entry into smooth muscle cells from rat aorta, an effect that can contribute for the protection of the cardiovascular system.
- 2019 ARIA Care pathways for allergen immunotherapyPublication . Bousquet, Jean; Pfaar, Oliver; Togias, Alkis; Schünemann, Holger J; Ansotegui, Ignacio; Papadopoulos, Nikolaos G; Tsiligianni, Ioanna; Agache, Ioana; Anto, Josep M.; Bachert, Claus; Bedbrook, Anna; Bergmann, Karl-Christian; Bosnic-Anticevich, Sinthia; Bosse, Isabelle; Brozek, Jan; Calderon, Moises A; Canonica, Giorgio W; Caraballo, Luigi; Cardona, Victoria; Casale, Thomas; Cecchi, Lorenzo; Chu, Derek; Costa, Elísio; Cruz, Alvaro A; Czarlewski, Wienczyslawa; Durham, Stephen R; Du Toit, George; Dykewicz, Mark; Ebisawa, Motohiro; Fauquert, Jean Luc; Fernandez-Rivas, Montserrat; Fokkens, Wytske J; Fonseca, João; Fontaine, Jean-François; Gerth van Wijk, Roy; Haahtela, Tari; Halken, Susanne; Hellings, Peter; Ierodiakonou, Despo; Iinuma, Tomohisa; Ivancevich, Juan Carlos; Jacobsen, Lars; Jutel, Marek; Kaidashev, Igor; Khaitov, Musa; Kalayci, Omer; Kleine Tebbe, Jörg; Klimek, Ludger; Kowalski, Marek L; Kuna, Piotr; Kvedarienė, Violeta; La Grutta, Stefania; Larenas Linnemann, Désirée; Lau, Susanne; Laune, Daniel; Le Thi Tuyet, Lan; Lodrup Carlsen, Karin; Lourenço, Olga; Malling, Hans-Jørgen; Marien, Gert; Menditto, Enrica; Mercier, Gregoire; Mullol, Joaquim; Muraro, Antonella; O'Hehir, Robyn; Okamoto, Yoshitaka; Pajno, Giovanni B; Park, Hae-Sim; Panzner, Petr; Passalacqua, Giovanni; Pham-Thi, Nhan; Roberts, Graham; Pawankar, Ruby; Rolland, Christine; Rosario, Nelson; Ryan, Dermot; Samolinski, Boleslaw; Sanchez-Borges, Mario; Scadding, Glenis; Shamji, Mohamed H; Sheikh, Aziz; Sturm, Gunter J; Todo-Bom, Ana; Toppila-Salmi, Sanna; Valentin Rostan, Marylin; Valiulis, Arunas; Valovirta, Erkka; Ventura, Maria Teresa; Wahn, Ulrich; Walker, Samantha; Wallace, Dana; Waserman, Susan; Yorgancioglu, Arzu; Zuberbier, TorstenAllergen immunotherapy (AIT) is a proven therapeutic option for the treatment of allergic rhinitis and/or asthma. Many guidelines or national practice guidelines have been produced but the evidence-based method varies, many are complex and none propose care pathways. This paper reviews care pathways for AIT using strict criteria and provides simple recommendations that can be used by all stakeholders including healthcare professionals. The decision to prescribe AIT for the patient should be individualized and based on the relevance of the allergens, the persistence of symptoms despite appropriate medications according to guidelines as well as the availability of good-quality and efficacious extracts. Allergen extracts cannot be regarded as generics. Immunotherapy is selected by specialists for stratified patients. There are no currently available validated biomarkers that can predict AIT success. In adolescents and adults, AIT should be reserved for patients with moderate/severe rhinitis or for those with moderate asthma who, despite appropriate pharmacotherapy and adherence, continue to exhibit exacerbations that appear to be related to allergen exposure, except in some specific cases. Immunotherapy may be even more advantageous in patients with multimorbidity. In children, AIT may prevent asthma onset in patients with rhinitis. mHealth tools are promising for the stratification and follow-up of patients.
- 3-Form Cosmology: Phantom Behaviour, Singularities and InteractionsPublication . Morais, João; Bouhmadi Lopez, Mariam; Marto, JoãoThe latest cosmological observations by the Planck collaboration (and combined with others) are compatible with a phantom-like behaviour (w < − 1) for the dark energy equation of state that drives the current acceleration of the Universe. With this mindset, we look into models where dark energy is described by a 3-form field minimally coupled to gravity. When compared to a scalar field, these models have the advantage of more naturally accommodating a cosmological-constant and phantom-like behaviours. We show how the latter happens for a fairly general class of positive-valued potentials, and through a dynamical system approach, we find that in such cases the 3-form field leads the Universe into a Little Sibling of the Big Rip singular event into the future. In this work, we explore the possibility of avoiding such singularity via an interaction in the dark sector between cold dark matter and the 3-form field. For the kind of interactions considered, we deduce a condition for replacing the LSBR by a late time de Sitter phase. For specific examples of interactions that meet this condition, we look for distinctive imprints in the statefinder hierarchy { S 3 ( 1 ) ; S 4 ( 1 ) } , { S 3 ( 1 ) ; S 5 ( 1 ) } , and in the growth rate of matter, e ( z ) , through the composite null diagnostic (CND).
- 3D and transient numerical modeling of door opening and closing processes and its influence on thermal performance of cold roomsPublication . Carneiro, Rui; Gaspar, Pedro Dinis; Silva, Pedro Dinho daThis paper presents the comparison of three-dimensional and transient CFD modelling of the opening and closing processes of hinged and sliding doors and its influence on the thermal performance of cold rooms. A species transport model is used to model a tracer gas. The air infiltration through the door opening is determined by the tracer gas concentration decay technique. The prediction of air temperature and velocity fields in the cold room as function of external air temperature allows quantifying the increase of the air infiltration rate and consequently of the average air temperature inside the cold room. When the hinged door is used, the formation of vortices during the opening movement promotes a larger and faster thermal interaction between the two contiguous air masses. The air infiltration during the sliding door opening/closing is 20% lower than for a hinged door. Consequently, the average air temperature inside the cold room is 17% lower. The air infiltration rate was numerically predicted and compared with analytical models’ results. The numerical model predicts closely the air infiltration rate for each door type. Moreover, the transient CFD modelling extends the results of the analytical models allowing the analysis of the influence of door opening and closing processes on the air temperature and velocity fields.
- 3D Printed Robotic Hand with Piezoresistive Touch CapabilityPublication . Fonseca, Gonçalo; Nunes-Pereira, João; Silva, AbilioThis work proposes the design of a low-cost sensory glove system that complements the operation of a 3D-printed mechanical hand prosthesis, providing it with the ability to detect touch, locate it and even measure the intensity of associated forces. Firstly, the production of the prosthetic model was performed using 3D printing, which allowed for quick and cheap production of a robotic hand with the implementation of a mechanical system that allows controlled movements with high performance and with the possibility of easily replacing each piece individually. Secondly, we performed the construction and instrumentation of a complementary sensory mimicry add-on system, focusing on the ability to sense touch as the primary target. Using piezoresistive sensors attached to the palm of the glove, a multi-sensor system was developed that was able to locate and quantify forces exerted on the glove. This system showed promising results and could be used as a springboard to develop a more complex and multifunctional system in the future.
- 3D Printed scaffolds with bactericidal activity aimed for bone tissue regenerationPublication . Correia, Tiago R.; Figueira, Daniela Sofia Rodrigues; Sá, Kevin; Miguel, Sónia P.; Fradique, Ricardo Gil; Mendonça, António; Correia, I.J.Nowadays, the incidence of bone disorders has steeply ascended and it is expected to double in the next decade, especially due to the ageing of the worldwide population. Bone defects and fractures lead to reduced patient’s quality of life. Autografts, allografts and xenografts have been used to overcome different types of bone injuries, although limited availability, immune rejection or implant failure demand the development of new bone replacements. Moreover, the bacterial colonization of bone substitutes is the main cause of implant rejection. To vanquish these drawbacks, researchers from tissue engineering area are currently using computer-aided design models or medical data to produce 3D scaffolds by Rapid Prototyping (RP). Herein, Tricalcium phosphate (TCP)/Sodium Alginate (SA) scaffolds were produced using RP and subsequently functionalized with silver nanoparticles (AgNPs) through two different incorporation methods. The obtained results revealed that the composite scaffolds produced by direct incorporation of AgNPs are the most suitable for being used in bone tissue regeneration since they present appropriate mechanical properties, biocompatibility and bactericidal activity.
- 3D Simulations of Droplets Impacting Liquid Films: Crown Parameters MeasurementsPublication . Vasconcelos, Daniel; Ribeiro, Daniela; Silva, R. D.; Barata, Jorge M MThe 3D incompressible Navier-Stokes equations are coupled with the CLSVOF method and employed to numerically simulate the phenomena of single droplet impact onto liquid films. A solution-adaptive mesh refinement tool, based on the gradient of the volume fraction scalar, is adopted in order to reduce computational cost. Three different fluids are taken into account: 100% jet fuel and 75%/25% and 50%/50% of jet fuel and biofuel, respectively. Quantitative analysis of the crown height and outer diameter is performed for different impact conditions, such as the influence of the impact velocity and dimensionless thickness, between experimental and numerical results, and the qualitative analysis includes the occurrence of splashing and overall crown evolution. Numerical results show that the crown outer diameter measurements are in good agreement with the experimental cases, presenting a slight discrepancy for the lower liquid film thickness of h*= 0.2. The crown height measurements are under-predicted for the current model, maintaining a similar trend for dimensionless thicknesses of h*= 0.5 and h*= 1 while, for the lower thickness, the crown disintegrates at earlier stages. The crown curvature and rim instabilities exhibit significant differences, and the splashing phenomenon occurs for both the experimental and numerical outcomes.
- 3D transient CFD modeling of sliding door operation and its influence on the thermal performance of cold roomsPublication . Carneiro, Rui; Gaspar, Pedro Dinis; Silva, Pedro Dinho daThe need of rationalize energy consumption in agrifood industry has fasten the development of methodologies to improve the thermal and energy performances of cold rooms. This paper presents a 3D transient Computational Fluid Dynamics (CFD) modelling of a cold room to evaluate the air infiltration rate through sliding doors. A species transport model is used for modelling the tracer concentration decay technique. Numerical predictions indicate that air temperature difference between spaces affects the air infiltration. For this case study, the infiltration rate increases 0.012 m3 s-1 per K of air temperature difference. The knowledge about the evolution of air infiltration during door opening/closing times allows to draw some conclusions about its influence on the air conditions inside the cold room, as well as to suggest best practices and simple technical improvements that can minimize air infiltration, and consequently improve thermal performance and energy consumption rationalization.
- 5-Hydrazinylethylidenepyrimidines effective against multidrug-resistant Acinetobacter baumannii: Synthesis and in vitro biological evaluation of antibacterial, radical scavenging and cytotoxic activitiesPublication . Figueiredo, Joana; Serrano, João L.; Soares, MN; Ferreira, Susana; Domingues, F.C.; Almeida, Paulo; Silvestre, SamuelAcinetobacter baumannii has emerged as an important nosocomial pathogen in recent years, with infectious outbreaks caused by multidrug-resistant strains increasing worldwide. Thus, new antibacterial treatments for multidrug-resistant A. baumannii strains are needed. In this work, a series of 5-hydrazinylethylidenepyrimidines were synthesized and in vitro evaluated against two multidrug-resistant A. baumannii strains (AcB 13/10 and AcB 73/10). Minimum inhibitory concentration results demonstrated that generally the compounds in study presented values in a low micromolar range. In the determination of in vitro bacterial growth at 24 h, it was observed that the pyrimidines 3a and 3c, with an unsubstituted hydrazinylphenyl, have bacteriostatic activity in both multidrug-resistant A. baumannii strains, with a concentration-dependent action. In general, an additive effect occurred in the combination of these compounds with gentamicin, rifampicin and polymyxin B, for both strains. Furthermore, all 5-hydrazinylethylidenepyrimidines under study presented a good 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, generally low xanthine oxidase inhibition and low cytotoxicity in normal human dermal fibroblasts as well as potential favorable drug-likeness properties. Thus, these molecules can be considered attractive for the future development of antibacterial agents against multidrug-resistant A. baumannii.
- 5α-Dihydrotestosterone regulates the expression of L-type calcium channels and calcium-binding protein regucalcin in human breast cancer cells with suppression of cell growthPublication . Marques, Ricardo; Peres, Carina; Vaz, Cátia; Gomes, Inês; Figueira, Marília I; Cairrão, Elisa; Verde, Ignacio; Baptista, Cláudio; Socorro, SílviaAndrogens have been associated with the development of normal breast, and their role in mammary gland carcinogenesis has also been described. Several studies reported that androgens inhibit breast cancer cell growth, whereas others linked their action with the modulation of calcium (Ca(2+)) pumps, Ca(2+) channels and Ca(2+)-binding proteins. Also, it is known that deregulated Ca(2+) homeostasis has been implicated in the pathophysiology of breast. The L-type Ca(2+) channels (LTCCs) were found to be up-regulated in colon, colorectal and prostate cancer, but their presence in breast tissues remains uncharacterized. On the other hand, regucalcin (RGN) is a Ca(2+)-binding protein involved in the control of mammary gland cell proliferation, which has been identified as an androgen target gene in distinct tissues except breast. This study aimed to confirm the expression and activity of LTCCs in human breast cancer cells and investigate the effect of androgens in regulating the expression of α1C subunit (Cav1.2) of LTCCs and Ca(2+)-binding protein RGN. PCR, Western blot, immunofluorescence and electrophysiological experiments demonstrated the expression and activity of Cav1.2 subunit in MCF-7 cells. The MCF-7 cells were treated with 1, 10 or 100 nM of 5α-dihydrotestosterone (DHT) for 24-72 h. The obtained results showed that 1 nM DHT up-regulated the expression of Cav1.2 subunit while diminishing RGN protein levels, which was underpinned by reduced cell viability. These findings first confirmed the presence of LTCCs in breast cancer cells and opened new perspectives for the development of therapeutic approaches targeting Ca(2+) signaling.