Browsing by Issue Date, starting with "2024-10"
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- Bdnf-NRF2 crosstalk in depression disorderPublication . Santos, Marlene; Caldevilla, Renato; Morais, Stephanie; Carvalho, Serafim; Medeiros, Rui; Barroso, Maria FátimaThe World Health Organization estimates that major depressive disorder (MDD) affects over 264 million individuals globally, posing a significant public health challenge. Treatment-resistant depression (TRD) represents a severe form of MDD with poor treatment outcomes. Genetic variations are known to impact MDD treatment responses, yet genome-wide association studies have struggled to identify consistent marker alleles. Previous research has linked the Brain Derived Neurotrophic Factor (BDNF) genetic polymorphism with TRD. BDNF is essential for neuronal survival and neuroplasticity, processes influenced by antidepressant treatment, and regulated by transcription factors like Nuclear factor erythroid 2-related factor 2 (NRF2). NRF2 regulates antioxidant and anti-inflammatory responses and plays a crucial role in depression pathogenesis. NRF2 knockout mice exhibit reduced BDNF levels and depression-like behaviors, indicating that NRF2activation enhances BDNF expression and antidepressant efficacy. The BDNF rs6265 (Val66Met) polymorphism is associated with variations in antidepressant response rates. Research suggests that the interaction between BDNF and NRF2 pathways could enhance antidepressant effectiveness. NRF2 activation, such as through the compound sulforaphane, has demonstrated rapid antidepressant effects by increasing BDNF expression. Lower levels of NRF2 and BDNF are observed in stress-induced depression models, and ketamine treatment influences NRF2-related genes. Simultaneously, there is a growing need for efficient genotyping methods, and genosensors offer a promising solution. This presentation will address the interplay between BDNF and NRF2 in depression, explore its relationship in antidepressant response, and present a putative genosensor for BDNF rs6265 (Val66Met) polymorphism identification, improving antidepressant treatment outcome.
- Repurposing antiplasmodial leads for cancer: Exploring the antiproliferative effects of N-cinnamoyl-aminoacridinesPublication . Fonte, Mélanie; Rôla, Catarina; Santana, Sofia; Ferraz, Ricardo; Prudêncio, Miguel; Almeida, Joana; Ferraz, Ricardo; Prudêncio, Cristina; Teixeira, Cátia; Gomes, PaulaDrug repurposing and rescuing have been widely explored as cost-effective approaches to expand the portfolio of chemotherapeutic agents. Based on the reported antitumor properties of both trans-cinnamic acids and quinacrine, an antimalarial aminoacridine, we explored the antiproliferative properties of two series of N-cinnamoyl-aminoacridines recently identified as multi-stage antiplasmodial leads. The compounds were evaluated in vitro against three cancer cell lines (MKN-28, Huh-7, and HepG2), and human primary dermal fibroblasts. One of the series displayed highly selective antiproliferative activity in the micromolar range against the three cancer cell lines tested, without any toxicity to non-carcinogenic cells.
- A custom-built single-channel in-ear electroencephalography sensor for sleep phase detection: an interdependent solution for at-home sleep studiesPublication . Borges, Daniel Filipe; Soares, Joana Isabel; Silva, Heloísa; Felgueiras, João; Batista, Carla; Ferreira, Simão; Rocha, Nuno; Leal, AlbertoSleep is vital for health. It has regenerative and protective functions. Its disruption reduces the quality of life and increases susceptibility to disease. During sleep, there is a cyclicity of distinct phases that are studied for clinical purposes using polysomnography (PSG), a costly and technically demanding method that compromises the quality of natural sleep. The search for simpler devices for recording biological signals at home addresses some of these issues. We have reworked a single-channel in-ear electroencephalography (EEG) sensor grounded to a commercially available memory foam earplug with conductive tape. A total of 14 healthy volunteers underwent a full night of simultaneous PSG, in-ear EEG and actigraphy recordings. We analysed the performance of the methods in terms of sleep metrics and staging. In another group of 14 patients evaluated for sleep-related pathologies, PSG and in-ear EEG were recorded simultaneously, the latter in two different configurations (with and without a contralateral reference on the scalp). In both groups, the in-ear EEG sensor showed a strong correlation, agreement and reliability with the ‘gold standard’ of PSG and thus supported accurate sleep classification, which is not feasible with actigraphy. Single-channel in-ear EEG offers compelling prospects for simplifying sleep parameterisation in both healthy individuals and clinical patients and paves the way for reliable assessments in a broader range of clinical situations, namely by integrating Level 3 polysomnography devices. In addition, addressing the recognised overestimation of the apnea-hypopnea index, due to the lack of an EEG signal, and the sparse information on sleep metrics could prove fundamental for optimised clinical decision making.
- Effectiveness of virtual reality in reducing public speaking anxiety: A pilot studyPublication . Oliveira, Maria; Almeida, Raquel Simões de; Gomes, Paulo Veloso; Donga, João; Marques, António; Teixeira, Bruno; Pereira, Javier; Simões de Almeida, Raquel; Machado Veloso Gomes, Paulo Sérgio; Rucha das Dores da Costa Donga, João Paulo; Pereira da Silva Marques, António JoséPublic speaking anxiety (glossophobia) is a manifestation of social anxiety that affects a significant portion of the population, jeopardizing performance in academic, professional, and social contexts. This pilot study examines the effectiveness of virtual reality (VR) as a therapeutic tool for reducing public speaking anxiety. Over six VR simulation sessions, the physiological responses of 30 participants, including heart rate (HR) and electrodermal activity, were monitored alongside psychometric assessments. Results demonstrated a significant reduction in HR and improved self-efficacy. These findings recommend combining VR with traditional therapeutic approaches and emerging neuroscience-based methods, such as neurofeedback, to create more personalized treatment interventions.
- Interaction devices for multi-sensory exploration in immersive environmentsPublication . Donga, João; Gomes, Paulo Veloso; Sá, Vitor; Marques, António; Pereira, Javier; Machado Veloso Gomes, Paulo Sérgio; Sá, Vítor J.; Pereira da Silva Marques, António JoséImmersive environments, such as virtual reality (VR) and augmented reality (AR), provide users with experiences that blend digital and physical worlds. Interaction devices play a critical role in facilitating these experiences by engaging multiple human senses—sight, sound, touch, smell, taste and vestibular. This paper explores the various interaction devices designed for multi-sensory exploration, their applications, and the challenges associated with creating a fully immersive multi-sensory experience. We analyze input and output devices, hybrid systems, and emerging technologies while addressing the challenges in synchronization, user comfort, and accessibility.
- Virtual reality exposure therapy for Arachnophobia: A pilot studyPublication . Lopes, Inês; Almeida, Raquel Simões de; Gomes, Paulo Veloso; Sá, Vítor J.; Oliveira, Gonçalo; Marques, António; Machado Veloso Gomes, Paulo Sérgio; Sá, Vítor J.; Pereira da Silva Marques, António José; Simões de Almeida, RaquelArachnophobia is a chronic disorder leading to significant avoidance of spider-related situations. This pilot study examines the effectiveness of Virtual Reality Exposure Therapy (VRET) for treating arachnophobia. The study included 25 participants who completed fear questionnaires and avoidance tests before, after and two weeks after the intervention. The intervention consisted of a session of progressive exposure to a novel and gamified virtual environment containing spiders. The results showed a significant reduction in fear and anxiety in relation to the phobic stimulus, suggesting that VRET is a promising approach for treating phobias, in controlled and safe environments.
- Mixed reality in surgery: Development of a mixed reality application for surgical trainingPublication . Lima, Ana Carolina; Vilaça, Adélio; Veloso, Rita; Marques, António; Pereira, Javier; Magalhaes, Renato; da Silva Veloso, Rita Sofia; Pereira da Silva Marques, António José; Magalhães, RenatoMixed reality (MR) technology combines the real and the virtual world in an innovative way, where the users can see and interact with both worlds at the same time, having several applications in surgical practice, planning, and training. A MR application was developed to be used in a head mounted display (Microsoft HoloLens 2) for surgical training of the anterior cruciate ligament reconstruction surgery, with the aim of indicating the position of the femoral tunnel. This application was tested by 11 surgeons of the Centro Hospitalar Universitário de Santo António, who have all completed the simulation successfully, with an average time of under a minute. These surgeons answered an inquiry of satisfaction, where they all highlighted the potential that MR has in surgical training.
- Segmentation of the bone structure from MRI Knee Joint - A use casePublication . Silva, Vasco; Vilaça, Adélio; Veloso, Rita; Coelho, Luís; Magalhães, Renato; Magalhães, RenatoManual and automatic segmentation techniques can be applied to DICOM medical images from magnetic resonance imaging (MRI) to extract certain structures, such as soft tissues, but the precise extraction of bone structures may be limited. This study studies these types of knee bone tissue segmentation on MRI, to avoid the need to resort to computed tomography (CT) for obtaining the desired bone structures. Manual segmentation was done using ITK-Snap and automatic segmentation algorithms were applied in Python and the ITK library. As a result of this study, it was found that although manual segmentation allowed for precise and consistent identification of the femur, tibia, fibula, and patella, the automatic segmentation needed to achieve the same level of accuracy.
- Virtual immersive training model with mixed reality for prosthesis application in orthopedicsPublication . Alves, Diogo; Gomes, Paulo Veloso; Magalhães, Renato; Pereira, João; Vilaça, Adélio; Marques, António; Machado Veloso Gomes, Paulo Sérgio; Pereira da Silva Marques, António JoséTraining medical professionals in Orthopedics faces several technical challenges. The equipment required for practical, hands-on training is often restricted to operating rooms. This constraint presents a significant issue, as developing the necessary skills to perform surgeries requires substantial practice time. This work developed a virtual training model using mixed reality, using a QR code to generate a virtual opaque hemisphere, within which the user operates two virtual tools that simulate an endoscope and a drill. A virtual monitor displays the endoscope’s view to the user, who must then navigate the drill tip to successfully touch specific target cubes. The application has the potential to significantly enhance the orthopedic learning experience by reducing the time and resources.
- Key principles involving ethical and deontological issues in military stress management training in virtual reality environmentsPublication . Gomes, Paulo Veloso; Vianez, Ana; Curado, Henrique; Marques, António; Pereira, Javier; Machado Veloso Gomes, Paulo Sérgio; Pereira da Silva Marques, António José; Curado, HenriqueThe integration of Virtual Reality in military contexts, which simulates realistic combat and high-risk operational scenarios, provides a controlled environment for developing various skills and psychological resilience. This technology has proven to be a valuable tool for enhancing soldiers’ training and preparedness. The creation and use of VR programs, especially those involving the collection of biofeedback data to study military stress, carry significant ethical and deontological responsibilities. This study examines the regulation of using powerful algorithms to analyse biofeedback data to study military stress, emphasizing informed consent, privacy and confidentiality, beneficence and nonmaleficence, transparency in data usage and compliance with legal and regulatory standards.