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- Production and Characterization of a Pullulan-Based Facial Mask Incorporating Grape Seed Flour Extract for Cosmeceutical ApplicationsPublication . Ferreira, Ester; Encarnação, Bárbara; Cascalheira, José Francisco; Ferreira, Susana; Ramos, Ana; Luís, Ângelo; Gallardo, Eugenia; Domingues, Fernanda; Magni, ChiaraThis study aimed to develop and characterize an eco-friendly facial mask based on the pullulan biopolymer incorporating grape seed flour extract, a sustainable source of polyphenols. The extract was characterized by its phenolic content, antioxidant capacity, enzyme inhibition and antimicrobial activity. High total phenolic and flavonoid contents, along with the presence of -resveratrol, conferred strong antioxidant activity. The extract effectively inhibited tyrosinase and elastase enzymes, indicating its anti-aging potential, and exhibited antimicrobial effects particularly against . The incorporation of the extract in pullulan films increased thickness and coloration while maintaining transparency and improving barrier properties. The bioactive films showed strong antioxidant activity and displayed selective antibacterial activity against , including MRSA strains. A facial mask prototype was successfully produced, demonstrating flexibility, solubility, and potential for topical applications. Overall, the developed pullulan-grape seed extract films exhibit multifunctional cosmeceutical potential combining antioxidant, antimicrobial, and anti-aging effects with sustainable valorization of wine industry by-products.
- Bioactive Potential of Wild Plants from Gardunha Mountain: Phytochemical Characterization and Biological ActivitiesPublication . Coimbra, Alexandra; Gallardo, Eugenia; Luís, Ângelo; Gaspar, Pedro Dinis; Ferreira, Susana; Duarte, Ana Paula; Adriana, IrinelThe plants used in folk medicine have been increasingly studied to identify their bioactive properties. Therefore, this study aimed to assess the bioactivity of the hydroethanolic extracts of plants collected in Gardunha Mountain, Portugal. Seven abundant and representative wild plants were studied: , , , , , , and . The phytochemical composition of the extracts was determined by UHPLC-timsTOF-MS and by spectrophotometric methods. The antioxidant, in vitro anti-inflammatory and antimicrobial activity and the biocompatibility of the extracts were tested. The extracts were predominantly composed of flavonoids and phenolic acids, such as gallic acid, neochlorogenic acid and quercetin glycosides. The extracts demonstrated very strong antioxidant activity related to scavenging free radicals (AAI = 2.84 and 2.93). Regarding antimicrobial activity, the extract exhibited inhibitory effects, particularly against Gram-positive bacteria and yeasts (MIC = 0.008-0.5 mg/mL). The , , and extracts showed low cytotoxicity (viability > 70%) in the highest concentration tested. These findings highlight and as promising sources of novel bioactive compounds, particularly antimicrobials in controlling microbial growth and promoting associated health benefits, and underscore the value of traditional medicinal plants as a guide for pharmacological studies.
- Eye discomfort at close work in Portuguese university students: A comparative analysis between the pre-COVID and confinement periodPublication . Nunes, Amélia Fernandes; Leitão, Mara Filipa Antunes; Nunes, António; Monteiro, PedroBackground Many individuals experience visual symptoms associated with near work. The level of discomfort appears to increase with the amount of digital screen use. Objective To study the eye discomfort with near tasks in university students in the pre-COVID period and in the period of confinement due to the pandemic. Methods Two independent samples of students, aged between 18 and 35 years, were used to assess symptomatic behaviour with the Convergence Insufficiency Symptom Survey (CISS) questionnaire. In the pre-COVID period the sample had 342 participants, 64.6% females and in the COVID period 322 students participated, 71.4% females. The study of differences was carried out by the Mann-Whitney U test. The interpretation of the statistical inference was performed for a significance level≤0.05. Results There was an increase in the number of symptomatic cases in the COVID period without statistical evidence of differences in the frequency of symptoms reported in the two periods. The dimensions "somatic sensations" and "cognitive performance" were the typology of symptoms that most contributed to visual complaints with near vision. There was a significantly different symptomatic behaviour between genders in the period of confinement (p = 0.001), worsening in females and improving in males. Conclusion These findings suggest that females and males exposed to digital environments, over time, may exhibit different symptomatic behaviour. Our results suggest that boys adapt more quickly than girls. Factors that predispose to these changes, aetiology and potential intervention actions still need further study.
- The role of ayahuasca in cell viability and oxidative stress in gastric adenocarcinoma cell linePublication . Gonçalves, Joana; Cascalheira, José; Valentão, Patrícia; Luís, Ângelo; Gallardo, Eugenia; Duarte, Ana PaulaAyahuasca, a psychoactive beverage native to the Amazon, originally derived from Banisteriopsis caapi stem scrapings and Psychotria viridis leaves, exhibits hallucinogenic properties due to N,Ndimethyltryptamine. When combined with β-carbolines, it enters the bloodstream and central nervous system, inhibiting monoamine oxidase-A. Over time, therapeutic effects have been associated to ayahuasca consumption. This study assessed the impact of extracts from three plant decoctions used in ayahuasca preparation on the gastric adenocarcinoma cell line (AGS). MTT reduction assays selected B. caapi, Mimosa hostilis, and Peganum harmala samples as most effective. Lactate dehydrogenase activity evaluated membrane integrity loss, while oxidative stress induction was measured using dihydroethidium and 2′,7′-dichlorodihydrofluorescein diacetate probes. Results revealed apoptosis induction in AGS Ucells, with all three samples significantly reducing oxidative stress.
- Comparative study of sample preparation procedures to determine the main compounds in ayahuasca beverages by QuEChERS and high‐performance liquid chromatography analysisPublication . Gonçalves, Joana; Rosado, Tiago; Barroso, Mário; Restolho, José; Fernández, Nicolás; Luís, Ângelo; Gallardo, Eugenia; Duarte, Ana PaulaIntroduction Ayahuasca is a psychoactive drink originally consumed by indigenous people of the Amazon. The lack of regulation of this drink leads to uncontrolled consumption, and it is often consumed in religious contexts. Objective The aim of this work is to compare three miniaturised extraction techniques for extracting the main ayahuasca compounds from beverages. Methodology Three sample pretreatment techniques were evaluated (dispersive liquid–liquid microextraction [DLLME], microextraction by packed sorbent [MEPS] and QuEChERS [Quick, Easy, Cheap, Effective, Rugged and Safe]) for the simultaneous extraction of N,N-dimethyltryptamine (DMT), tetrahydroharmine (THH), harmine, harmaline, harmol and harmalol from ayahuasca beverage samples. Then, the most promising technique (QuEChERS) was chosen to pre-concentrate the analytes, subsequently detected by high-performance liquid chromatography coupled to a diode array detector (HPLC-DAD). Results The procedure was optimised, with the final conditions being 500 μL of extractor solvent, 85 mg of primary secondary amine (PSA) and 4 s of vortexing. The analytical method was validated, showing to be linear between 0.16 and 10 μg/mL for β-carbolines and between 0.016 and 1 μg/mL for DMT, with coefficients of determination (R2) between 0.9968 and 0.9993. The limit of detection (LOD) and lower limit of quantification (LLOQ) were 0.16 μg/mL for all compounds, except for DMT (0.016 μg/mL) and extraction efficiencies varied between 60.2% and 88.0%. Conclusion The analytical methodology proved to be accurate and precise, with good linearity, LODs and LLOQs. This method has been fully validated and successfully applied to ayahuasca beverage samples.
- The Role of Ayahuasca in Colorectal Adenocarcinoma Cell Survival, Proliferation and Oxidative StressPublication . Gonçalves, Joana; Feijó, Mariana; Socorro, Sílvia; Luís, Ângelo; Gallardo, Eugenia; Duarte, Ana PaulaThe psychedelic beverage ayahuasca is originally obtained by Banisteriopsis caapi (B. caapi) (BC) and Psychotria viridis (P. viridis) (PV). However, sometimes these plant species are replaced by others that mimic the original effects, such as Mimosa hostilis (M. hostilis) (MH) and Peganum harmala (P. harmala) (PH). Its worldwide consumption and the number of studies on its potential therapeutic effects has increased. This study aimed to evaluate the anticancer properties of ayahuasca in human colorectal adenocarcinoma cells. Thus, the maximum inhibitory concentration (IC50) of decoctions of MH, PH, and a mixture of these (MHPH) was determined. The activities of caspases 3 and 9 were evaluated, and the cell proliferation index was determined through immunocytochemical analysis (Ki-67). Two fluorescent probes were used to evaluate the production of oxidative stress and the activity of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) was also evaluated. It was demonstrated that exposure to the extracts significantly induced apoptosis in Caco-2 cells, while decreasing cell proliferation. MH and MHPH samples significantly reduced oxidative stress and significantly increased glutathione peroxidase activity. No significant differences were found in SOD activity. Overall, it was demonstrated that the decoctions have a potential anticancer activity in Caco-2 cells.
- Attribution of somatosensory properties to an upper limb prosthesisPublication . Fonseca, Gonçalo; Nunes-Pereira, João; Pereira Silva, AThe nervous system is a complex network composed by cells, tissue, and organs that have the ability of receiving, transmit, regulate, and send information and stimuli, not only within our body but from our surroundings1. This information is produced by a complex system of neurochemical and electrical reactions that produce the perceptions of heat, smell, taste, proprioception, and touch that lead to physical reactions (movement)2. When that transmission of information is lost due to malformations or accident, there are several physiological responses that will either be lost or try to find new pathways to function and make sense out the current situation. Bringing the division of this work into three phases. The first phase, the production of the prosthetic model by 3D printing (Fig. 1a), reducing the time-consuming production of the different parts by changing production characteristics like infill, layer height, surface quality, ironing and type of material used. The second phase, the instrumentalization of the prosthetic (Fig. 1b) focussing on allowing it to function by controlled and regulated force execution, with lowcost servomotors and components, with easy access to replacement. The third phase, the construction of the sensing mimicking, add-on sensory system using piezoresistive sensors attached to the palm side of a glove on specific regions that allowed not only the location and detection of the forces being exerted, but also their quantification (Fig. 1c). The type of instrumentalization planning used on the sensory glove, allow an easier access to the sensors and other components, making it quite to replace or to adapt . Overall, the results produced were very promising, and better than expected, allowing not only the localization and measurement of force, and analog read for each sensor without too much signal interference, but also a better access and cost reduction prototype.
- First Chemical Profile Analysis of Acacia PodsPublication . Pedro, Soraia; Fernandes, Tiago A.; Luís, Ângelo; Antunes, A M M; Gonçalves, J. C.; Gominho, Jorge; Gallardo, Eugenia; Anjos, OféliaThis study intended to evaluate the potential industrial applications of various Acacia species (Acacia melanoxylon, Acacia longifolia, Acacia cyclops, Acacia retinodes, Acacia pycnantha, Acacia mearnsii, and Acacia dealbata) by examining their chemical composition, antioxidant, and antimicrobial properties. Using high-resolution mass spectrometry, a comprehensive analysis successfully identified targeted compounds, including flavonoids (flavonols/flavones) and phenolic acids, such as 4-hydroxybenzoic acid, p-coumaric acid, and ellagic acid. Additionally, p-coumaric acid was specifically identified and quantified within the hydroxycinnamic aldehydes. This comprehensive characterization provides valuable insights into the chemical profiles of the studied species. Among the studied species, A. pycnantha exhibited a higher concentration of total phenolic compounds, including catechin, myricetin, quercetin, and coniferaldehyde. Furthermore, A. pycnantha displayed notable antibacterial activity against K. pneumoniae, E. coli, S. Typhimurium, and B. cereus. The identified compounds in Acacia pods and their shown antibacterial activities exhibit promising potential for future applications. Moreover, vibrational spectroscopy was a reliable method for distinguishing between species. These significant findings enhance our understanding of Acacia species and their potential for various industrial applications.
- 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.
- A Systematic Review on the Therapeutic Effects of AyahuascaPublication . Gonçalves, Joana; Luís, Ângelo; Gallardo, Eugenia; Duarte, Ana PaulaTraditional therapies, resorting to the use of plants, have acquired a great demand over the years, both for economic reasons and the preference for natural treatments. Some studies suggest that ayahuasca may have beneficial properties in treating some physical and psychological imbalances. Thus, we carried out a systematic review of studies published up to December 2022, where these themes were addressed. The search was carried out in the PubMed database, and only studies written in English and published in peer-reviewed journals were included. Thus, 228 publications were identified, of which 66 were included in the present study. The reviewed studies suggest that ayahuasca may have beneficial effects on various physical and psychological conditions, namely in the treatment of depression, anxiety and various diseases of the neurobiological system, as well as anti-inflammatory and antimicrobial properties, demonstrating its therapeutic potential. The number of studies that address this issue has also been growing, demonstrating interest in the search for alternative treatments. However, to the best of our knowledge, this is the first systematic review where all the findings of therapeutic effects associated with the consumption of ayahuasca are reviewed.
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