Cognitive stimulation for portuguese older adults with cognitive impairment: a randomized controlled trial of efficacy, comparative duration, feasibility and experiential relevance

Although some studies point to cognitive stimulation as a beneficial therapy for older adults with cognitive impairments, this area of research and practice is still lacking dissemination and is underrepresented in many countries. Moreover, the comparative effects of different intervention durations remain to be established and, besides cognitive effects, pragmatic parameters, such as cost-effectiveness and experiential relevance to participants, are seldom explored. In this work, we present a randomized con- trolled wait-list trial evaluating 2 different intervention durations (standard 1⁄4 17 vs brief 1⁄4 11 sessions) of a cognitive stimulation program developed for older adults with cognitive impairments with or without dementia. 20 participants were randomly assigned to the standard duration intervention program (17 sessions, 1.5 months) or to a wait-list group. At postintervention of the standard intervention group, the wait-list group crossed over to receive the brief intervention program (11 sessions, 1 month). Changes in neuropsychological, functionality, quality of life, and caregiver outcomes were evaluated. Experience during intervention and costs and feasibility were also evaluated. The current cognitive stimulation programs (ie, standard and brief) showed high values of experiential relevance for both intervention durations. High adherence, completion rates, and reasonable costs were found for both formats. Further studies are needed to definitively establish the potential efficacy, optimal duration, cost-effectiveness, and experiential relevance for participants of cognitive intervention approaches.

Abnormal interactions between context, memory structure, and mood in schizophrenia: an ERP investigation

This study used event-related potentials to examine interactions between mood, sentence context, and semantic memory structure in schizophrenia. Seventeen male chronic schizophrenia and 15 healthy control subjects read sentence pairs after positive, negative, or neutral mood induction. Sentences ended with expected words (EW), within-category violations (WCV), or between-category violations (BCV). Across all moods, patients showed sensitivity to context indexed by reduced N400 to EW relative to both WCV and BCV. However, they did not show sensitivity to the semantic memory structure. N400 abnormalities were particularly enhanced under a negative mood in schizophrenia. These findings suggest abnormal interactions between mood, context processing, and connections within semantic memory in schizophrenia, and a specific role of negative mood in modulating semantic processes in this disease.

TP perturbation of TN matrices and totally positive directions

Here, we define and consider (linear) TP-directions and TP-paths for a totally nonnegative matrix, in an effort to more deeply understand perturbation of a TN matrix to a TP matrix. We give circumstances in which a TP-direction exists and an example to show that they do not always exist. A strategy to give (nonlinear) TP-paths is given (and applied to this example). A long term goal is to understand the sparsest TP-perturbation for application to completion problems.

Controlo e gestão da produção no setor de corte térmico

Dissertação de mestrado integrado em Engenharia Mecânica

Auxetic effect of natural fiber knitted fabrics

Since they present a negative Poisson's radio, auxetic materials are different from conventional ones. These materials present an unusual behaviour: when stretched (elongated in the longitudinal direction), their cross-section is increased. There are two different ways to obtain auxetic materials: through polymers or through structures. It is possible to affirm that those obtained through fibrous structures are very recent and that few authors have been dedicated to their study. The main objective of this work is to study the effect of the negative Poisson

Low frequency of TERT promoter mutations in gastrointestinal stromal tumors (GISTs).

Somatic mutations in the promoter region of telomerase reverse transcriptase (TERT) gene, mainly at positions c. − 124 and c. − 146 bp, are frequent in several human cancers; yet its presence in gastrointestinal stromal tumor (GIST) has not been reported to date. Herein, we searched for the presence and clinicopathological association of TERT promoter mutations in genomic DNA from 130 bona fide GISTs. We found TERT promoter mutations in 3.8% (5/130) of GISTs. The c. − 124C4T mutation was the most common event, present in 2.3% (3/130), and the c. − 146C4T mutation in 1.5% (2/130) of GISTs. No significant association was observed between TERT promoter mutation and patient’s clinicopathological features. The present study establishes the low frequency (4%) of TERT promoter mutations in GISTs. Further studies are required to confirm our findings and to elucidate the hypothetical biological and clinical impact of TERT promoter mutation in GIST pathogenesis.

Thin films composed of Ag nanoclusters dispersed in TiO2: Influence of composition and thermal annealing on the microstructure and physical responses

Noble metal powders containing gold and silver have been used for many centuries, providing different colours in the windows of the medieval cathedrals and in ancient Roman glasses. Nowadays, the interest in nanocomposite materials containing noble nanoparticles embedded in dielectric matrices is related with their potential use for a wide range of advanced technological applications. They have been proposed for environmental and biological sensing, tailoring colour of functional coatings, or for surface enhanced Raman spectroscopy. Most of these applications rely on the so-called localised surface plasmon resonance absorption, which is governed by the type of the noble metal nanoparticles, their distribution, size and shape and as well as of the dielectric characteristics of the host matrix. The aim of this work is to study the influence of the composition and thermal annealing on the morphological and structural changes of thin films composed of Ag metal clusters embedded in a dielectric TiO2 matrix. Since changes in size, shape and distribution of the clusters are fundamental parameters for tailoring the properties of plasmonic materials, a set of films with different Ag concentrations was prepared. The optical properties and the thermal behaviour of the films were correlated with the structural and morphological changes promoted by annealing. The films were deposited by DC magnetron sputtering and in order to promote the clustering of the Ag nanoparticles the as-deposited samples were subjected to an in-air annealing protocol. It was demonstrated that the clustering of metallic Ag affects the optical response spectrum and the thermal behaviour of the films.

The influence of nitrogen and oxygen additions on the thermal characteristics of aluminium-based thin films

The ternary aluminium oxynitride (AlNxOy) system offers the possibility to obtain a wide range of properties by tailoring the ratio between pure Al, AlNx and AlOy and therefore opening a significant number of possible applications. In this work the thermal behaviour of AlNxOy thin films was analysed by modulated infrared radiometry (MIRR), taking as reference the binary AlOy and AlNx systems. MIRR is a non-contact and non-destructive thermal wave measurement technique based on the excitation, propagation and detection of temperature oscillations of very small amplitudes. The intended change of the partial pressure of the reactive gas (N2 and/or O2) influenced the target condition and hence the deposition characteristics which, altogether, affected the composition and microstructure of the films. Based on the MIRR measurements and their qualitative and quantitative interpretation, some correlations between the thermal transport properties of the films and their chemical/physical properties have been found. Furthermore, the potential of such technique applied in this oxynitride system, which present a wide range of different physical responses, is also discussed. The experimental results obtained are consistent with those reported in previous works and show a high potential to fulfil the demands needed for the possible applications of the systems studied. They are clearly indicative of an adequate thermal response if this particular thin film system is aimed to be applied in small sensor devices or in electrodes for biosignal acquisition, such as those for electroencephalography or electromyography as it is the case of the main research area that is being developed in the group.

Polysaccharide-based freestanding multilayered membranes exhibiting reversible switchable properties

The design of self-standing multilayered structures based on biopolymers has been attracting increasing interest due to their potential in the biomedical field. However, their use has been limited due to their gel-like properties. Herein, we report the combination of covalent and ionic cross-linking, using natural and non-cytotoxic cross-linkers, such as genipin and calcium chloride (CaCl2). Combining both cross-linking types the mechanical properties of the multilayers increased and the water uptake ability decreased. The ionic cross-linking of multilayered chitosan (CHI)â alginate (ALG) films led to freestanding membranes with multiple interesting properties, such as: improved mechanical strength, calcium-induced adhesion and shape memory ability. The use of CaCl2 also offered the possibility of reversibly switching all of these properties by simple immersion in a chelate solution. We attribute the switch-ability of the mechanical properties, shape memory ability and the propensity for induced-adhesion to the ionic cross-linking of the multilayers. These findings suggested the potential of the developed polysaccharide freestanding membranes in a plethora of research fields, including in biomedical and biotechnological fields.

Synthesis, antiangiogenesis evaluation and molecular docking studies of 1-Aryl-3-[(thieno[3,2-b]pyridin-7-ylthio)phenyl]ureas: Discovery of a new substitution pattern for type II VEGFR-2 Tyr kinase inhibitors

The synthesis and biological evaluation of novel 1-aryl-3-[2-, 3- or 4-(thieno[3,2-b]pyridin-7-ylthio)phenyl]ureas 3, 4 and 5 as VEGFR-2 tyrosine kinase inhibitors, are reported. The 1-aryl-3-[3-(thieno[3,2-b]pyridin-7-ylthio)phenyl]ureas 4a-4h, with the arylurea in the meta position to the thioether, showed the lowest IC50 values in enzymatic assays (10-206 nM), the most potent compounds 4d-4h (IC50 10-28 nM) bearing hydrophobic groups (Me, F, CF3 and Cl) in the terminal phenyl ring. A convincing rationalization was achieved for the highest potent compounds 4 as type II VEGFR-2 inhibitors, based on the simultaneous presence of: (1) the thioether linker and (2) the arylurea moiety in the meta position. For compounds 4, significant inhibition of Human Umbilical Vein Endothelial Cells (HUVECs) proliferation (BrdU assay), migration (wound-healing assay) and tube formation were observed at low concentrations. These compounds have also shown to increase apoptosis using the TUNEL assay. Immunostaining for total and phosphorylated (active) VEGFR-2 was performed by Western blotting. The phosphorylation of the receptor was significantly inhibited at 1.0 and 2.5 microM for the most promising compounds. Altogether, these findings point to an antiangiogenic effect in HUVECs.

O evento levou... Comunicação de marca de uma cidade-sede

Tese de Doutoramento em Ciências da Comunicação - Especialidade em Comunicação Estratégica e Organizacional

Projeto de produção de tubo elíptico em aço avançado de elevada resistência para uma serra de arco

Dissertação de mestrado integrado em Engenharia Mecânica

Targeting lactate transport suppresses in vivo breast tumour growth.

BACKGROUND Most cancers, including breast cancer, have high rates of glucose consumption, associated with lactate production, a process referred as "Warburg effect". Acidification of the tumour microenvironment by lactate extrusion, performed by lactate transporters (MCTs), is associated with higher cell proliferation, migration, invasion, angiogenesis and increased cell survival. Previously, we have described MCT1 up-regulation in breast carcinoma samples and demonstrated the importance of in vitro MCT inhibition. In this study, we performed siRNA knockdown of MCT1 and MCT4 in basal-like breast cancer cells in both normoxia and hypoxia conditions to validate the potential of lactate transport inhibition in breast cancer treatment. RESULTS The effect of MCT knockdown was evaluated on lactate efflux, proliferation, cell biomass, migration and invasion and induction of tumour xenografts in nude mice. MCT knockdown led to a decrease in in vitro tumour cell aggressiveness, with decreased lactate transport, cell proliferation, migration and invasion and, importantly, to an inhibition of in vivo tumour formation and growth. CONCLUSIONS This work supports MCTs as promising targets in cancer therapy, demonstrates the contribution of MCTs to cancer cell aggressiveness and, more importantly, shows, for the first time, the disruption of in vivo breast tumour growth by targeting lactate transport.

Acetylated bacterial cellulose coated with urinary bladder matrix as a substrate for retinal pigment epithelium

This work evaluated the effect of acetylated bacterial cellulose (ABC) substrates coated with urinary bladder matrix (UBM) on the behavior of Retinal Pigment Epithelium (RPE), as assessed by cell adhesion, proliferation and development of cell polarity exhibiting transepithelial resistance and polygonal shaped-cells with microvilli. Acetylation of bacterial cellulose (BC) generated a moderate hydrophobic surface (around 65°) while the adsorption of UBM onto these acetylated substrates did not affect significantly the surface hydrophobicity. The ABS substrates coated with UBM enabled the development of a cell phenotype closer to that of native RPE cells. These cells were able to express proteins essential for their cytoskeletal organization and metabolic function (ZO-1 and RPE65), while showing a polygonal shaped morphology with microvilli and a monolayer configuration. The coated ABC substrates were also characterized, exhibiting low swelling effect (between 1.52.0 swelling/mm3), high mechanical strength (2048 MPa) and non-pyrogenicity (2.12 EU/L). Therefore, the ABC substrates coated with UBM exhibit interesting features as potential cell carriers in RPE transplantation that ought to be further explored.

Estudo das tecnologias de interatividade no processo de compra em contexto das lojas de vestuário on-line

Dissertação de mestrado em Design de Comunicação de Moda