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- Synthetic cannabinoids in biological specimens: a review of current analytical methods and sample preparation techniquesPublication . Rosado, Tiago; Gonçalves, Joana; Luís, Ângelo; Malaca, Sara; Soares, Sofia; Vieira, Duarte Nuno; Barroso, Mário; Gallardo, EugeniaSynthetic cannabinoids are a new class of chemical drugs capable of modifying human behavior. These products do not contain cannabis, but produce similar effects after consumption. The fact that they are easily accessed, and are many times considered to be harmless, justifies their widespread use among young people. This fact, together with the difficulty in their detection by routine drug tests, makes it extremely important to develop new procedures able to detect and monitor their consumption. The aim of this work is to perform a critical review regarding the human biological samples that can be used for the determination of synthetic cannabinoids, paying special attention to analytical methods and sample preparation techniques. The reviewed articles deal with the determination of synthetic cannabinoids in the context of forensic and toxicological analysis.
- Assessment of the Bioaccessibility and Bioavailability of the Phenolic Compounds of Prunus avium L. by in Vitro Digestion and Cell ModelPublication . Gonçalves, Joana; Ramos, Rodrigo; Luís, Ângelo; Rocha, Sandra; Rosado, Tiago; Gallardo, Eugenia; Duarte, Ana PaulaThe fruit of Prunus avium L., commonly known as sweet cherry, is an excellent source of phytochemicals, namely, phenolic compounds. This study aims to determine in vitro the bioavailability and the bioactivity of phenolic compounds present in cherries. Caco-2 cells were used, and the permeability and integrity of the monolayer formed were investigated. After incubation, the phenolic compounds that permeabilized the cell monolayer were quantified using a high-performance liquid chromatography–diode array detector, and the antioxidant activity was evaluated by the 1,1-diphenyl-2-picrylhydrazyl method. The results demonstrated that the phenolic compounds of sweet cherries after undergoing a simulated digestion were absorbed by the cellular barrier, becoming bioavailable. Contrary to what was found after incubation with the in vitro digested extract, the integrity of the cell monolayer was altered and its permeability increased upon incubation with the sweet cherry phenolic extract. Regarding the antioxidant activity, it was verified that this decreased after the absorption by the cellular monolayer. This study suggests that digestion is an indispensable process for absorption because without it the phenolic content of the food matrix does not become bioaccessible.
- Novel synthetic opioids - toxicological aspects and analysisPublication . Tabarra, Inês Pires; Soares, Sofia; Rosado, Tiago; Gonçalves, Joana; Luís, Ângelo; Malaca, Sara; Barroso, Mário; Keller, Thomas; Restolho, José; Gallardo, EugeniaOver the past few years, there has been an emerging number of new psychoactive drugs. These drugs are frequently mentioned as "legal highs", "herbal highs", "bath salts" and "research chemicals". They are mostly sold and advertised on online forums and on the dark web. The emerging new psychoactive substances are designed to mimic the effects of psychoactive groups, which are often abused drugs. Novel synthetic opioids are a new trend in this context and represent an alarming threat to public health. Given the wide number of fatalities related to these compounds reported within the last few years, it is an important task to accurately identify these compounds in biologic matrices in order to administer an effective treatment and reverse the respiratory depression caused by opioid related substances. Clinicians dealing with fentanyl intoxication cases should consider that it could, in fact, be a fentanyl analogue. For this reason, it is a helpful recommendation to include synthetic opioids in the routine toxicological screening procedures, including analysis in alternative matrices, if available, to investigate poly-drug use and possible tolerance to opioids. To address this public health problem, better international collaboration, effective legislation, effective investigation, control of suspicious "research chemicals" online forums and continuous community alertness are required. This article aims to review diverse reported fatalities associated with new synthetic opioids describing them in terms of pharmacology, metabolism, posology, available forms, as well as their toxic effects, highlighting the sample procedures and analytical techniques available for their detection and quantification in biological matrices.
- Refinement of two-dimensional electrophoresis for vitreous proteome profiling using an artificial neural networkPublication . Santos, Fátima Raquel Milhano dos; Albuquerque, Tânia Gonçalves; Gaspar, Leonor Isabel Mesquita ; Dias, Joao ML; Sousa, João Paulo Castro De; Paradela, Alberto; Tomaz, C. T.; Passarinha, LADespite technological advances, two-dimensional electrophoresis (2DE) of biological fluids, such as vitreous, remains a major challenge. In this study, artificial neural network was applied to optimize the recovery of vitreous proteins and its detection by 2DE analysis through the combination of several solubilizing agents (CHAPS, Genapol, DTT, IPG buffer), temperature, and total voltage. The highest protein recovery (94.9% ± 4.5) was achieved using 4% (w/v) CHAPS, 0.1% (v/v) Genapol, 20 mM DTT, and 2% (v/v) IPG buffer. Two iterations were required to achieve an optimized response (580 spots) using 4% (w/v) CHAPS, 0.2% (v/v) Genapol, 60 mM DTT, and 0.5% (v/v) IPG buffer at 35 kVh and 25 °C, representing a 2.4-fold improvement over the standard initial conditions of the experimental design. The analysis of depleted vitreous using the optimized protocol resulted in an additional 1.3-fold increment in protein detection over the optimal output, with an average of 761 spots detected in vitreous from different vitreoretinopathies. Our results clearly indicate the importance of combining the appropriate amount of solubilizing agents with a suitable control of the temperature and voltage to obtain high-quality gels. The high-throughput of this model provides an effective starting point for the optimization of 2DE protocols. This experimental design can be adapted to other types of matrices. Graphical abstract.
- Production of Hydrophobic Zein-Based Films Bioinspired by The Lotus Leaf Surface: Characterization and Bioactive PropertiesPublication . Luís, Ângelo; Domingues, F.C.; Ramos, AnaHydrophobic zein-based functional films incorporating licorice essential oil were successfully developed as new alternative materials for food packaging. The lotus-leaf negative template was obtained using polydimethylsiloxane (PDMS). The complex surface patterns of the lotus leaves were transferred onto the surface of the zein-based films with high fidelity (positive replica), which validates the proposed proof-of-concept. The films were prepared by casting method and fully characterized by Scanning Electron Microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC). The grammage, thickness, contact angle, mechanical, optical and barrier properties of the films were measured, together with the evaluation of their biodegradability, antioxidant and antibacterial activities against common foodborne pathogens (Enterococcus faecalis and Listeria monocytogenes). The zein-based films with the incorporation of licorice essential oil presented the typical rugosities of the lotus leaf making the surfaces very hydrophobic (water contact angle of 112.50°). In addition to having antioxidant and antibacterial properties, the films also shown to be biodegradable, making them a strong alternative to the traditional plastics used in food packaging.
- COVID-19 in children: A Systematic review and meta-analysisPublication . Amaral, Leonor; Luís, Ângelo; Gallardo, Eugenia; Domingues, Fernanda C.; Pereira, LuísaThe consumption of new psychoactive substances (NPSs) has been increasing, and this problem affects several countries worldwide. There is a class of NPSs of natural origin, consisting of plants and fungi, which have a wide range of alkaloids, responsible for causing relaxing, stimulating or hallucinogenic effects. The consumption of some of these substances is prompted by religious beliefs and cultural reasons, making the legislation very variable or even ambiguous. However, the abusive consumption of these substances can present an enormous risk to the health of the individuals, since their metabolism and effects are not yet fully known. Additionally, NPSs are widely spread over the internet, and their appearance is very fast, which requires the development of sophisticated analytical methodologies, capable of detecting these compounds. Thus, the objective of this work is to review the toxicological aspects, traditional use/therapeutic potential and the analytical methods developed in biological matrices in twelve plant specimens (Areca catechu, Argyreia nervosa, Ayahuasca, Catha edulis, Datura stramonium, Lophophora williamsii, Mandragora officinarum, Mitragyna speciosa, Piper methysticum Forst, Psilocybe, Salvia divinorum and Tabernanthe iboga).
- Pullulan Films Containing Rockrose Essential Oil for Potential Food Packaging ApplicationsPublication . Luís, Ângelo; Ramos, Ana; Domingues, F.C.Active packaging is designed to control the development of decay- and disease-causing microorganisms and is emerging as a promising technology for extending shelf-life, maintaining food safety, reducing waste, and minimizing the risks for foodborne diseases. The goal of this work was to develop and characterize bioactive pullulan-based films, containing rockrose (Cistus ladanifer) essential oil. Among other abundant compounds (camphene, bornyl acetate and trans-pinocarveol), α-pinene was identified as the major compound of rockrose essential oil (39.25%). The essential oil presented stronger antibacterial activity against Gram-positive than against Gram-negative bacteria. The antioxidant results indicate the potential of the developed films to be used to package foods susceptible to oxidation and rancification, thus improving their shelf-life. Also, this study reflects the potential of rockrose essential oil, free or incorporated in pullulan, as a promising quorum sensing inhibitor, since it was able to interrupt intercellular communication, inhibiting violacein production. Electronic microscopy images showed the antibiofilm activity of the films with rockrose essential oil that were able to influence bacterial adhesion, which may be explained by the differences in the surface free energy of the films, as also determined.
- Ayahuasca Beverages: Phytochemical Analysis and Biological PropertiesPublication . Gonçalves, Joana; Luís, Ângelo; Gradillas, Ana; García, Antonia; Restolho, José; Fernández, Nicolás; Domingues, F.C.; Gallardo, Eugenia; Duarte, Ana PaulaAyahuasca is a psychoactive beverage, originally consumed by indigenous Amazon tribes, of which consumption has been increasing worldwide. The aim of this study was to evaluate the phytochemical profile, as well as the antioxidant, anti-inflammatory and antimicrobial properties of decoctions of four individual plants, a commercial mixture and four mixtures of two individual plants used in the Ayahuasca preparation. For this purpose, a phytochemical characterization was performed, determining the content of flavonoids, total phenolic compounds, and analyzing the phenolic profile. Besides, 48 secondary metabolites were investigated by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q/TOF-MS) and their concentration estimated with real standards when present. The antioxidant activity was evaluated by both the β-carotene bleaching test and DPPH free radical scavenging assay, and the anti-inflammatory activity was determined by a protein denaturation method. Finally, the antimicrobial properties were evaluated using the disc diffusion assay, resazurin microtiter method, anti-quorum sensing and anti-biofilm activity assays. The obtained results showed that, in general, the samples have a high content of phenolic compounds and flavonoids with noticeable differences, reflecting on remarkable antioxidant and anti-inflammatory activities. Significant antimicrobial properties were also observed, with emphasis on the effect of B. caapi and P. harmala on planktonic and biofilm cells of A. baumannii, inhibiting both the biofilm formation and the production of violacein pigment.
- Evaluation of the In Vitro Wound-Healing Activity and Phytochemical Characterization of Propolis and HoneyPublication . Afonso, Alexandra M.; Gonçalves, Joana; Luís, Ângelo; Gallardo, Eugenia; Duarte, Ana P.Honey and propolis are natural substances produced by Apis mellifera that contain flavonoids, phenolic acids, and several other phytochemicals. The aim of this study was to phytochemically characterize three different types of honey and propolis, both separately and mixed, and to evaluate their wound-healing activity. Total phenolic compounds and flavonoids were determined using the Folin–Ciocalteu’s and aluminum chloride colorimetric methods, respectively. The antioxidant activity was evaluated by both the DPPH free radical scavenging assay and β-carotene bleaching test, and the anti-inflammatory activity was determined by a protein denaturation method. To evaluate the wound-healing activity of the samples, NHDF cells were subjected to a wound scratch assay. The obtained results showed that dark-brown honey presents a higher concentration of phenolic compounds and flavonoids, as well as higher antioxidant and anti-inflammatory activities. Propolis samples had the highest concentrations in bioactive compounds. Examining the microscopic images, it was possible to verify that the samples promote cell migration, demonstrating the wound-healing potential of honey and propolis.
- Psilocybin as a New Approach to Treat Depression and Anxiety in the Context of Life-Threatening DiseasesPublication . Vargas, Ana Sofia; Luís, Ângelo; Barroso, Mário; Gallardo, Eugenia; Pereira, L.Psilocybin is a naturally occurring tryptamine known for its psychedelic properties. Recent research indicates that psilocybin may constitute a valid approach to treat depression and anxiety associated to life-threatening diseases. The aim of this work was to perform a systematic review with meta-analysis of clinical trials to assess the therapeutic effects and safety of psilocybin on those medical conditions. The Beck Depression Inventory (BDI) was used to measure the effects in depression and the State-Trait Anxiety Inventory (STAI) was used to measure the effects in anxiety. For BDI, 11 effect sizes were considered (92 patients) and the intervention group was significantly favored (WMD = -4.589; 95% CI = -4.207 to -0.971; p-value = 0.002). For STAI-Trait, 11 effect sizes were considered (92 patients), being the intervention group significantly favored when compared to the control group (WMD = -5.906; 95% CI = -7.852 to -3.960; p-value ˂ 0.001). For STAI-State, 9 effect sizes were considered (41 patients) and the intervention group was significantly favored (WMD = -6.032; 95% CI = -8.900 to -3.164; p-value ˂ 0.001). The obtained results are promising and emphasize the importance of psilocybin translational research in the management of symptoms of depression and anxiety, since the compound may be effective in reducing symptoms of depression and anxiety in conditions that are either resistant to conventional pharmacotherapy or for which pharmacologic treatment is not yet approved. Moreover, it may be also relevant for first-line treatment, given its safety.
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