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- O Registo dos Paços do ConcelhoPublication . Pinto, Susana Alcina RibeiroO Sistema Registal Português constitui um instrumento jurídico indispensável no âmbito da estabilidade do tráfico jurídico imobiliário. Na verdade, a sua finalidade essencial consiste em publicitar ou dar a conhecer a situação jurídica dos prédios. Esta publicidade provocada, não se confunde com qualquer outra, uma vez que se trata de uma publicidade com efeitos jurídicos, isto é, tem uma finalidade jurídica que consiste na segurança do comércio sobre imóveis. Trata-se de uma publicidade dinâmica porque abrange todo o comércio jurídico imobiliário e não apenas a segurança estática entre os contratantes intervenientes dos respetivos títulos. Um sistema de registo bem organizado, como é o português, proporciona informação credível e confiável e, ao mesmo tempo, célere e a custos consideravelmente baixos. Sem um sistema registal, os intervenientes no mercado dos imóveis teriam de gastar muito tempo e muito dinheiro para saber quem são os verdadeiros proprietários ou que ónus ou encargos incidem sobre os prédios. Um dos princípios enformadores do sistema registal português é o da instância ou do pedido. O pedido de registo deve ser acompanhado com os documentos indispensáveis para a prova legal do facto sujeito a registo, devendo ser corretamente instruído, tendo em vista uma qualificação favorável ou definitiva. Um dos conteúdos mais importantes da atividade do Solicitador, consiste, a par da autenticação de documentos particulares que contêm factos sujeitos a registo, na organização e promoção de atos de registo. Para isso, deve ter formação jurídica adequada e rigorosa sobre esta matéria, tendo em vista a obtenção de decisão favorável sobre questões que apresentam elevada complexidade jurídica.
- Assessment of the presence of Acinetobacter spp. resistant to β-lactams in commercial ready-to-eat salad samplesPublication . Costa-Ribeiro, Ana; Azinheiro, Sarah; Mota, Sandra; Prado, Marta; Lamas, Alexandre; Garrido-Maestu, AlejandroAcinetobacter baumannii is a well-known nosocomial infection causing agent. However, other Acinetobacter spp. have also been implicated in cases of human infection. Additionally, these bacteria are known for the development of antibiotic resistance thus making the treatment of the infections they cause, challenging. Due to their relevance in clinical setups less attention has been paid to their presence in foods, and its relation with infection/ dissemination routes. In the current study commercial Ready-To-Eat (RTE) salads were analyzed seeking for antibiotic resistant Acinetobacter spp. A preliminary screening allowed us to recover Gram-negative bacteria resistant to β – lactams using cefotaxime, third generation cephalosporins, as the selective agent, and this was followed by identification with CHROMagar™ Acinetobacter and 16S rDNA sequencing. Finally, the isolates identified as Acinetobacter spp. were reanalyzed by PCR to determine the presence of nine potential Extended Spectrum β Lactamases (ESBL). Two commercial RTE salad brands were included in the study (2 batches per brand and 8 samples of each batch making a total of 32 independent samples), and compared against an organic lettuce. High concentrations of β – lactam, resistant bacteria were found in all the samples tested (5 log CFU/g). Additionally, 209 isolates were phenotypically characterized on CHROMagar Acinetobacter. Finally, PCR analysis identified the presence of different ESBL genes, being positive for blaACC, blaSHV, blaDHA and blaVEB; out of these, blaACC was the most prevalent. None of the isolates screened were positive for more than one gene. To conclude, it is important to highlight the fact that pathogenic species within the genus Acinetobacter spp., other than A. baumannii, have been identified bearing resistance genes not typically associated to these microorganisms highlight the importance of continuous surveillance.
- Central and peripheral involvement of the retina in the initial stages of diabetic retinophatyPublication . Santos, Ana Rita; Almeida, Ana Catarina; Rocha, Ana Cláudia; Reste-Ferreira, Débora; Marques, Inês Pereira; Martinho, António Cunha-Vaz; Mendes, Luís; Santos, Torcato; Lewis, Warren; Cunha-Vaz, José; Santos, Ana RitaTo determine the degree of central microvascular closure using optical coherence tomography angiography in eyes of patients with type 2 diabetes with visible lesions only in the central retina or only in the periphery. Cross-sectional study. All 127 eyes underwent ultra-widefield fundus photography 200° examinations with OPTOS California (Optos, Dunfermline, United Kingdom) and Cirrus Angioplex optical coherence tomography angiography 3 × 3 mm acquisitions (ZEISS, Dublin, CA). Twenty-five eyes showed visible lesions only in the central retina, 57 only in the peripheral retina, and 45 presented visible lesions in entire retina. The group with visible lesions only in the periphery showed definite closure in the superficial capillary plexus in 49% of the eyes, whereas the group with visible lesions only in the central seven-early treatment diabetic retinopathy study fields area showed a definite closure in 64%. Central capillary closure is already present in the initial stages of diabetic retinopathy even when lesions are only visible in the peripheral retina. Capillary closure in the superficial capillary plexus is three times more frequent than in the deep capillary plexus, demonstrating earlier closure of the superficial capillary plexus. Eyes with visible lesions only in the periphery show a milder form of retinopathy.
- High-value compounds in papaya by-products (Carica papaya L. var. Formosa and Aliança): Potential sustainable use and exploitationPublication . Vinha, Ana F.; Costa, Anabela S. G.; Santo, Liliana Espírito; Ferreira, Diana M.; Sousa, Carla; Pinto, Edgar; Almeida, Agostinho; Oliveira, Maria Beatriz P. P.Food waste is a global and growing problem that is gaining traction due to its environmental, ethical, social, and economic repercussions. Between 2022 and 2027, the worldwide papaya market is expected to have a huge increase, meaning a growth in organic waste, including peels and seeds. Thus, this study evaluated the potential use of peels and seeds of two mature papaya fruits as a source of bioactive compounds, converting these by-products into value-added products. Proximate analysis (AOAC methods), mineral content (ICP-MS), free sugars (HPLC-ELSD), fatty acid composition (GC-FID), vitamin E profile (HPLC-DAD-FLD), and antioxidant activity (DPPH and FRAP assays) were evaluated. Both by-products showed high total protein (20–27%), and dietary fiber (32–38%) contents. Papaya peels presented a high ash content (14–16%), indicating a potential application as a mineral source. 14 fatty acids were detected, with α-linolenic acid (30%) as the most abundant in the peels and oleic acid (74%) in the seeds. Both by-products showed high antioxidant activity. Conclusion: Papaya by-products display great potential for industrial recovery and application, such as formulation of new functional food ingredients.
- Integração de princípios de economia circular nas operações e cadeias de abastecimento de uma indústria motores elétricos: um estudo de casoPublication . Andrade, Guilherme de Souza; Pereira, Maria Teresa Ribeiro; Boelter, Natália MadalenaThe electric motor market is undergoing remarkable growth, driven by its adoption across various industrial sectors. This increasing demand underscores the critical need for effective end-of-life management strategies for electric motors and the responsible handling of the high-value materials embedded within them. This dissertation endeavors to formulate a comprehensive framework for the integration of circular economy principles into the supply chain of the electric motor industry. The literature review revealed that methodologies for selecting the best end-of-life scenario for industrial electric motors are still a scarce topic. Among the identified strategies, recycling emerges as the primary focus area for research. Motor recovery, albeit underexplored, is recognized as pivotal in extending product lifecycles. To gain a comprehensive understanding of the current landscape, an exhaustive analysis of winding processes has been conducted. This analysis encompasses an in-depth review of the supply chain for the resins utilized in motor impregnation and the copper employed for winding. Furthermore, a close examination of the service sector responsible for motor recovery has been undertaken. Subsequently, the proposed circular economy framework is systematically applied to the processes and supply chain of the electric motor industry. This framework is designed to serve as an inaugural step, facilitating the industry's adoption of circular economy strategies. Implementation of these strategies has the potential to significantly enhance the overall sustainability performance of the electric motor industry.
- Betão leve de estrutural aplicado a sistemas de fachadas pré-fabricadasPublication . Tamura, Rodrigo Teruaki; Oliveira, Maria do Rosário Santos; Garcia, Maria da Luz do Vale; Real, Lígia VitóriaThe use of precast concrete parts is no longer a novelty in the civil construction market. Several authors cite the advantages of its use, such as reduced construction time added to greater durability of the structure. One of the limitations of its use is the weight of the pieces, which require specific equipment for assembly. The present study aimed to develop lightweight concrete mixtures using a dosage method based on particle packing, for application in precast concrete panel pieces. For the dosage of these concretes, a particle packing method was used, which consists in improving the distribution between the materials used (gravel, clay, EPS, sand and cement) by filling the voids that are left between the materials of larger size with those of smaller size. Through the tests performed, the concretes presented positive results, reaching strengths above 30 MPa and spreads above 600 mm. Therefore, it can be concluded that the method used presents great potential when the objective is linked to concretes that use lightweight aggregates for precast parts. Analyzing the relationship between the calculation methodology used, the structural verifications performed, the results and the applicability of the final products generated, it can be concluded that its application generates impacts such as reducing the weight of the structure and the amount of steel used without affecting the structural balance of the model.
- IL-10 and Cdc42 as critical modulators in methamphtamine-induced neuroinflammationPublication . Silva, Ana Isabel; Socodato, Renato; Pinto, Carolina; Terceiro, Ana Filipa; Canedo, Teresa; Relvas, João Bettencourt; Saraiva, Margarida; Summavielle, Teresa; Summavielle, TeresaPsychoactive substances, such as Methamphetamine (Meth), can induce complex neuroinflammatory responses that modulate the neuron-glia cross talk and strongly affect behavioral responses. Recently we have reported that Meth stimulates astrocytes to release tumor necrosis factor (TNF) and glutamate, leading to microglial activation, microgliosis and loss of risk-assessment. Here, we started by investigating the anti-inflammatory power the cytokine interleukin-10 (IL-10), resorting to astrocyte and microglia primary transfected with different FRET probes and exposed to Meth (100µM), to elucidate the mechanisms involved. Then after, we confirmed these results in vivo, by employing a transgenic mouse model that overexpresses IL-10 (pMT-10), in time-controlled manner, and administering a binge Meth dosing (4 x 5mg/kg, with 2h intervals). In vitro, our findings reveal that the presence of recombinant IL-10 (rIL-10) counteracts Meth-induced excessive glutamate release in astrocytes, which significantly reduced microglial activation. This reduction was associated with the modulation of astrocytic intracellular calcium (Ca2+) dynamics, particularly by restricting the release of Ca2+ from the endoplasmic reticulum to the cytoplasm. Furthermore, we identify the small Rho GTPase Cdc42 as a crucial intermediary in the astrocyte-to-microglia communication pathway under Meth. In vivo, we observed that IL-10 overexpressing prevented Meth-induced neuroinflammation, microgliosis and Meth-induced behavioral changes. These findings enhance our understanding of Meth-related neuroinflammatory mechanisms, suggesting IL-10 and Cdc42 as putative therapeutic targets, and strengthen the view of a neuroimmune nature for addiction.
- Microglial RAC1 drives experience-dependent brain plasticityPublication . Almeida, Tiago O.; Portugal, Camila C.; Santos, Evelyn C. S.; Moreira, Joana Tedim; Ferreira, João Galvão; Canedo, Teresa; Magalhães, Ana; Summavielle, Teresa; Summavielle, TeresaMicroglia, the immune defenders of the brain, continuously extend and retract their processes to sense and decipher their local environment. This includes interactions with synapses to maintain brain homeostasis. To do this, microglia rely on the actin cytoskeleton and subsequent intracellular signaling, which is adapted in response to external signals released by cells undergoing intense synaptic activity. Thus, proteins that regulate actin cytoskeleton dynamics, intracellular trafficking, and integration of extracellular signaling, such as RhoA, Rac1 and Cdc42 from the Rho GTPase family, are good candidates to govern microglial sensing capacity and homeostasis. In this study, using conditional cellspecific gene targeting in mice combined with multi-omics approaches, immunofluorescence, and behavioral tests we aimed to identify the roles of Rho GTPase Rac1 in microglia homeostasis. We demonstrate that the Rho GTPase Rac1 is essential for microglia to sense and interpret their local microenvironment. This impacts the microglia-synapse crosstalk that is required for experiencedependent plasticity, a fundamental brain property impaired in several neuropsychiatric disorders. Furthermore, phosphoproteomics profiling of microglia isolated from mice exposed to an environmental enrichment protocol (known to induce experience-dependent synaptic plasticity and cognitive performance) detects a large modulation of Rho GTPase signaling, predominantly of Rac1. Additionally, our results show that environmental enrichment likely requires tight regulation of Rho GTPase-dependent pathways. Ablation of microglial Rac1 affected pathways involved in microglia-synapse communication, disrupted experience-dependent synaptic remodeling and blocked the gains in learning, memory, and sociability induced by environmental enrichment. Overall, our results place microglial Rac1 as a central regulator of pathways involved in the microglia-synapse crosstalk required for experience-dependent synaptic plasticity and cognitive performance, suggesting that modulation of Rho GTPase signaling in microglia might be a useful strategy to boost neuroplasticity in health and disease.
- The role of RAC1 in methamphtamine-induced neuroinflammationPublication . Terceiro, Ana Filipa; Canedo, Teresa; Silva, Ana Isabel; Magalhães, Ana; Relvas, João; Summavielle, Teresa; Summavielle, TeresaMethamphetamine (Meth), a powerful psychostimulant, induces detrimental neuroinflammatory responses, in the brain reward system that seem to contribute to maintenance of addictive behaviour. Yet, the mechanisms regulating these processes in microglial cells are not clear. We have previously shown that exposing WT mice to Meth (4x5 mg/kg, 2h intervals) induces microgliosis concomitant with decreased microglia cell volume and ramification. Furthermore, psychostimulants are known to induce structural plasticity mechanisms in neurons, and Rho GTPases, important regulators of the actin cytoskeleton, are involved in these responses. Here, we assessed Rho GTPases, specifically rhoA, rac1 and cdc42, activation in response to Meth in microglia. Exposing WT mice to the same pattern of Meth administration, we found an increase in the activation of rac1 in the striatum, 15 min following the last administration of Meth. To further explore these results, we then used a conditional mice model for ablation of rac1 in adult microglia (Rac1fl/fl:Cx3cr1CreER+) and exposed these mice to the same pattern of Meth administration. Rac1 ablation was sufficient to prevent Meth-induced morphological alterations in the striatum. Currently, we are assessing the role of rac1 in the behavioural response to Meth, using a locomotor sensitization test. Overall, we identified rac1 as a novel target of Meth in microglial cells. With these results, we expect to clarify if targeting Rho GTPases may contribute to improving the treatment of addictive disorders.
- Biomechanical assessment methods used in chronic stroke: A scoping review of non-linear approachesPublication . Freitas, Marta; Pinho, Francisco; Pinho, Liliana; Silva, Sandra; Figueira, Vânia; Vilas-Boas, João Paulo; Silva, AugustaNon-linear and dynamic systems analysis of human movement has recently become increasingly widespread with the intention of better reflecting how complexity affects the adaptability of motor systems, especially after a stroke. The main objective of this scoping review was to summarize the non-linear measures used in the analysis of kinetic, kinematic, and EMG data of human movement after stroke. PRISMA-ScR guidelines were followed, establishing the eligibility criteria, the population, the concept, and the contextual framework. The examined studies were published between 1 January 2013 and 12 April 2023, in English or Portuguese, and were indexed in the databases selected for this research: PubMed®, Web of Science®, Institute of Electrical and Electronics Engineers®, Science Direct® and Google Scholar®. In total, 14 of the 763 articles met the inclusion criteria. The non-linear measures identified included entropy (n = 11), fractal analysis (n = 1), the short-term local divergence exponent (n = 1), the maximum Floquet multiplier (n = 1), and the Lyapunov exponent (n = 1). These studies focused on different motor tasks: reaching to grasp (n = 2), reaching to point (n = 1), arm tracking (n = 2), elbow flexion (n = 5), elbow extension (n = 1), wrist and finger extension upward (lifting) (n = 1), knee extension (n = 1), and walking (n = 4). When studying the complexity of human movement in chronic post-stroke adults, entropy measures, particularly sample entropy, were preferred. Kinematic assessment was mainly performed using motion capture systems, with a focus on joint angles of the upper limbs.
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