Veritati
Repositório Institucional da Universidade Católica Portuguesa
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Predictors of lung cancer patients' behavioral intention to use virtual reality for treatment preparedness and shared decision-making: a unified theory of acceptance and use of technology-based perception study
Publication . Elkefi, Safa; Feiner, Steven K.; Matthews, Alicia K.; Rocha, Luís M.; Gershenson-Garcia, Carlos; Scheinmann, Roberta
Objectives: We examined the intention of lung cancer patients to use virtual reality (VR) to support shared decisionmaking and treatment preparedness and identified predictors of this intention using the Unified Theory of Acceptance and Use of Technology (UTAUT). Methods: Two hundred cancer patients completed a survey. Logistic regression was used to identify the predictors of VR use for decision-making. Results: 89.5% were willing to use VR; willing participants were younger than those who were not willing (60.8 ± 15.3 years; P< .001). Digital literacy was high in 89%, whereas health literacy was marginal/limited in 85%. Willingness was associated with greater technology use (P = .009). Performance expectancy strongly predicted intention: motivation to engage (Yes OR = 6.93; 95% CI, [4.06, 11.84]) and gaining knowledge (Yes OR = 15.20; 95% CI, [4.39, 52.56]); all P< .001. Effort expectancy (ease of navigation) was significant (Easy OR = 7.16; 95% CI, [2.50, 20.49]; P< .001), while mental/physical workload were not (P = .312/.732). Social influence from family/friends (OR = 3.38; 95% CI, [1.29, 8.84]; P = .016) and valuing family involvement (OR = 3.30; 95% CI, [1.32, 8.22]; P = .015) predicted intention; clinician encouragement did not (P = .283). Facilitating conditions were robust: peers also using VR (OR = 4.23; 95% CI, [1.46, 12.26]; P = .010), having assistance (OR = 7.05; 95% CI, [2.54, 19.61]; P = .0002), and clear instructions (OR = 20.60; 95% CI, [6.87, 61.75]; P< .001). Conclusions: Findings indicate high receptivity to VR and highlight actionable levers, including usability, family engagement, assistance, and instructional supports, for implementation in oncology care.
Decoding voltage-gated sodium channels structure: molecular mechanisms linking architecture, function, and disease
Publication . Boazinha, João Pedro; Carneiro, João; Cerqueira, Nuno M. F. S. A.; Sousa, Sérgio F.
Voltage-gated sodium (NaV) channels are critical transmembrane proteins responsible for the initiation and propagation of electrical signals in excitable tissues. They consist of a large α subunit and auxiliary β subunits. Together, the voltage sensing, ion selectivity, and rapid gating transitions regulate neuronal, muscular, and cardiac excitability. Recent cryo-electron microscopy breakthroughs have transformed the understanding of NaV structure–function relationships, revealing the asymmetric organization of voltage-sensing domains (VSD), the architecture of the DEKA selectivity filter, the mechanical coupling between S4–S5 linkers and S6 gating helices, and the allosteric mechanism by which the IFMT motif mediates fast inactivation. Across the nine human NaV isoforms, subtle structural divergences underlie distinct tissue distributions, biophysical properties, and disease susceptibilities, explaining the diverse channelopathies that range from epilepsy and cardiac arrhythmias to skeletal muscle disorders and painful neuropathies. These high-resolution structures also illuminate isoform-specific pharmacological pockets, including membrane-dependent cavities in VSD4 and dynamic fenestrations that govern state-dependent drug access, enabling the rational design of small molecules, peptide toxins, and hybrid therapeutics with improved selectivity. Advances in structural biology, biochemistry, and computation have established an integrated mechanistic model that connects NaV channels architecture to gating, inactivation, isoform-specific function, and human disease. This growing molecular atlas now supports next-generation precision therapies aimed at selectively modulating NaV channels activity in neurological, muscular, cardiac, and pain disorders.
Impact of pulsed electric fields and high pressure processing pre-treatments on physicochemical, sensory, and microbiological quality of freeze-dried beetroot snacks
Publication . Orvalho, T.; Dias, S.; Pino-Hernández, E.; Gonçalves, D.; Monteiro, V.; Alves, M.; Gomes, A.; Machado, D.; Soares, I.; Pinto, C.; Saraiva, J.
Freeze-drying is widely recognized as one of the most effective dehydration methods for preserving the organoleptic properties and nutritional value of fruits and vegetables when compared to conventional drying techniques. However, the high energy consumption resulting from long processing times constrains its application at an industrial scale1. In this context, the development of assisted freeze-drying processes using emerging technologies has gained increasing attention. Nonthermal approaches such as Pulsed Electric Fields (PEF) and High-Pressure Processing (HPP) have demonstrated potential as a pretreatment to enhance drying efficiency, promote tissue permeabilization and induce structural modifications that facilitate mass transfer, while simultaneously preserving or even improving the quality and sensory attributes of the final products2,3. These structural modifications are essential for enhancing flavour incorporation, enabling the efficient infusion of solutes into the vegetable matrix. Consequently, these strategies are especially relevant in light of the growing demand for high-quality vegetable snacks within more sustainable food systems, contributing to the development of value- added dehydrated products1,2. The present study aimed to evaluate the effect of nonthermal emerging processing technologies, namely PEF and HPP, as pre-treatments in the development of a freeze-dried beetroot snack produced from low-caliber beetroot. The impact of these approaches on the physicochemical, sensory, and microbiological properties of the final product was assessed, while simultaneously targeting the valorisation of non-marketable vegetables for the development of new value-added food products, within a framework of sustainability and the promotion of circular economy principles. Low-caliber beetroot (Beta vulgaris) samples were sanitized and subjected to different pre-treatments using PEF (1.5 kV/cm; 5.4 kJ/kg) and HPP (450 MPa for 5 min) to enhance flavour incorporation by inducing cellular structural changes that modify membrane permeability and facilitate mass transfer. For the PEF pretreatment, beetroot samples were initially processed, then cut into cubes (10x10x10 mm) and mixed with salicornia and spices. For the HPP pretreatment, after sanitization, samples were cut into cubes (10x10x10 mm), mixed with salicornia and spices, vacuum-packaged, and subsequently subjected to HPP. Control samples were also prepared, consisting of cubed beetroot seasoned with salicornia and spices, without any pretreatment. Both pretreated and control samples were subsequently freeze-dried using an industrial freeze-dryer, with a total cycle time of 50 h and an initial temperature of −40 °C. Primary drying was carried out for 43 h, with temperatures ranging from −40 °C to 35 °C, under a vacuum between 1 mbar and 0.15 mbar. Secondary drying lasted 7 h, at temperatures between 37 °C and 40 °C, operating at an approximate vacuum of 0.025 mbar. Samples were then vacuum packed in polyamide/polyethylene bags to avoid rehydration. Sensory attributes (colour, aroma, flavour, texture, and overall acceptance) and purchase intention were evaluated. Analyses were performed in triplicate to evaluate physicochemical properties (texture and colour) and microbiological compliance within the scope of hygienic-sanitary control. At the sensory level, both PEF and HPP pretreatments showed a positive impact compared to the control samples. However, between both technologies studied, HPP proved to be slightly more promising, particularly in colour and flavour. Samples treated with HPP were preferred by consumers and showed the highest purchase intention. Regarding texture, significant differences were observed in the hardness parameter between control and those treated with PEF and HPP, indicating that the pretreatments influenced the mechanical resistance of the product. This result suggests increased crispness, in agreement with the sensory analysis findings. When it comes to instrumental colour, significant differences were observed in the lightness (L*), greenness/redness (a*), and blueness/yellowness (b*) parameters in HPP-treated samples compared to the others (PEF and control), corroborating the sensory analysis results, particularly in terms of consumer preference for colour. From a microbiological perspective, HPP treatment showed a significant effect in reducing microbial load when compared to the control and PEF pre-treated samples. Indeed, a 2-log reduction was observed in the total number of viable microorganisms at 30 °C, while Enterobacteriaceae counts were below the detection limit in HPP-treated samples, while no significant reduction in microbial load was observed for the PEF pre-treatment. These results highlight the potential of HPP, as a nonthermal technology, to enhance the microbiological safety of food products. The results highlight the potential of PEF and HPP technologies, when applied as pretreatments, in the development of dehydrated products, with particular emphasis on the improvement of sensory properties, where HPP stood out compared to PEF. In addition, HPP demonstrated high efficacy in reducing microbial load, reinforcing its relevance as a nonthermal technology for the development of freeze-dried products. Overall, these findings underline the contribution of these approaches to the valorisation of low-commercial-value raw materials through the production of value-added dehydrated foods.
Innovative food product development from underutilized crops and crop wild relatives for sustainable and healthy diets
Publication . Geraldo, Rafaela; Duarte, Rafael; Kaur, Harsimran; Machado, Joana; Pinto, Elisabete; Vasconcelos, Marta
Red light, green light: activity fragmentation and all-cause mortality in United States adults
Publication . Gruda, Dritjon
Purpose: Physical-activity epidemiology treats how much people move as the health-relevant exposure. We asked whether activity fragmentation, the probability that movement gives way to rest, predicts all-cause mortality independently of activity volume, and how the two compare as predictors. Methods: In a prospective cohort analysis, we pooled the 2003–2004 and 2005–2006 cycles of the National Health and Nutrition Examination Survey, which used the same hip-worn accelerometer and protocol, and linked them to mortality through 2019. Adults aged 20 years or older with at least four valid wear days were eligible (N = 5973). Fragmentation was the active-to-sedentary transition probability. Survey-weighted Cox models adjusted for volume, demographic and socioeconomic characteristics, smoking, alcohol, hypertension, diabetes and cardiovascular history. Results: Over a median 14.4 years, 1429 participants died. Each standard-deviation increase in fragmentation carried a 19% higher hazard of death (hazard ratio 1.19, 95% confidence interval 1.09–1.30). Volume remained protective in the same model (0.83, 0.75–0.92). Fragmentation added more to a model containing volume than volume added to one containing fragmentation. Higher education predicted more fragmented movement; income did not. Conclusions: Activity fragmentation carries mortality information that activity volume does not, and is the stronger of the two predictors.