63 research outputs found

    Efficacy, Stability, and Safety Evaluation of New Polyphenolic Xanthones Towards Identification of Bioactive Compounds to Fight Skin Photoaging

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    Antioxidants have long been used in the cosmetic industry to prevent skin photoaging, which is mediated by oxidative stress, making the search for new antioxidant compounds highly desirable in this field. Naturally occurring xanthones are polyphenolic compounds that can be found in microorganisms, fungi, lichens, and some higher plants. This class of polyphenols has a privileged scaffold that grants them several biological activities. We have previously identified simple oxygenated xanthones as promising antioxidants and disclosed as hit, 1,2-dihydroxyxanthone (1). Herein, we synthesized and studied the potential of xanthones with different polyoxygenated patterns as skin antiphotoaging ingredients. In the DPPH antioxidant assay, two newly synthesized derivatives showed IC₅₀ values in the same range as ascorbic acid. The synthesized xanthones were discovered to be excellent tyrosinase inhibitors and weak to moderate collagenase and elastase inhibitors but no activity was revealed against hyaluronidase. Their metal-chelating effect (FeCl₃ and CuCl₂) as well as their stability at different pH values were characterized to understand their potential to be used as future cosmetic active agents. Among the synthesized polyoxygenated xanthones, 1,2-dihydroxyxanthone (1) was reinforced as the most promising, exhibiting a dual ability to protect the skin against UV damage by combining antioxidant/metal-chelating properties with UV-filter capacity and revealed to be more stable in the pH range that is close to the pH of the skin. Lastly, the phototoxicity of 1,2-dihydroxyxanthone (1) was evaluated in a human keratinocyte cell line and no phototoxicity was observed in the concentration range tested.This research was supported by national funds through FCT, Foundation for Science and Technology, within the scope of UIDB/04423/2020 and UIDP/04423/2020 under the project PTDC/SAU-PUB/28736/2017 (reference POCI-01-0145-FEDER-028736), cofinanced by COMPETE 2020, Portugal 2020 and the European Union through the ERDF and by FCT through national funds, as well as CHIRALBIOACTIVE-PI-3RL-IINFACTS-2019, and supported by the Applied Molecular Biosciences Unit-UCIBIO which is financed by national funds from FCT/MCTES (UID/Multi/04378/2019). Thanks are also due to FCT, the European Union, QREN, FEDER, COMPETE, by funding cE3c center (Ref. UID/BIA/00329/2019) and Direcao Regional da Ciencia e Tecnologia (Azores Government) by funding Azorean Biodiversity Group.info:eu-repo/semantics/publishedVersio

    Using a 3-tier Training Model for Effective Exchange of Good Practices in as ERASMUS+ Project

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    VISIR+ is an Erasmus+ project that aims to develop educational modules for electric and electronic circuits theory and practice following an enquiry-based teaching and learning methodology. The project has installed five new VISIR remote labs in Higher Education Institutions located in Argentina and Brazil, to allow students doing more experiments and hence acquire better experimental skills, through a combination of traditional (hands-on), remote and virtual laboratories. A key aspect for the success of this project was to motivate and train teachers in the underpinning educational methodology. As such, VISIR+ adopted a 3-tier training process to effectively support the use of VISIR in the Institutions that received it. This process is based on the “train the trainer” approach, which required the participating partner institutions to identify and engage a number of associated partners, interested in using their newly installed remote lab. To measure the quality of the training process, the same satisfaction questionnaire was used in all training actions. This paper presents a detailed description of the training actions along with the analysis of the satisfaction questionnaire results. Major conclusions are that the quality level of the training process remained practically the same across all training actions and that trainees sometimes considered the practical use of the VISIR remote lab as difficult, irrespectively of where and when the training action took place.info:eu-repo/semantics/publishedVersio

    New heterocyclic polyphenols with skin anti-aging potential

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    Xanthones or dibenzo-gamma-pyrones are heterocyclic polyphenolic compounds that can be found in microorganisms, fungi, lichens, and some higher plants. Structure-activity relationship studies emerged from a library of natural and synthetic polyoxygenated have suggested that xanthones with vicinal diol groups have promising antioxidant activity. Antioxidants have long been used in the cosmetic industry to prevent or minimize skin aging which is mediated by oxidative stress, making the search for new antioxidant agents highly desirable in this field. Considering the structure-activity relationship studies, it was hypothesized that trioxygenated xanthones could be promising antioxidants with potential as skin anti-aging ingredients. Hence, the synthesis of trioxygenated xanthones was attempted by the Smiles rearrangement pathway and also via acyl radical cyclization. The Smiles rearrangement pathway failed to yield the ester intermediate that was essential in this approach and was therefore abandoned. In the acyl radical cyclization method it was possible to obtain the 1,4-dihydroxy-3-methoxy-9H-xanthen-9-one. The antioxidant activity of this new xanthone as well as of four other polyoxygenated xanthones was evaluated by the DPPH assay, and two new derivatives showed IC50 values in the same range as the ascorbic acid. Almost all of the compounds were excellent tyrosinase inhibitors, more active than control inhibitor kojic acid. Concerning the other skin-degrading enzymes, the compounds tested were weak to moderate collagenase inhibitors, and showed no activity against elastase. The stability in presence of metal ions (FeCl3 and CuCl2) and dependence of the pH of their aqueous solutions was also studied, as well as their solubility in water and glycerol. Finally, the phototoxicity of the most promising xanthone was evaluated in a human keratinocyte cell line and no phototoxicity was observed in the concentration range tested, which is an important requirement for topical ingredients. Acknowledgements: This work was developed under the Strategic Funding UID/Multi/04423/2019 and Project No. POCI-01-0145-FEDER-028736, co-financed by COMPETE 2020, Portugal 2020 and the European Union through the ERDF, and by FCT through national funds, QREN,FEDER, COMPETE, by funding the cE3c centre (Ref. UID/BIA/00329/2019) and Azores DRCT for funding ABG. This work was also supported by the Applied Molecular Biosciences Unit-UCIBIO which is financed by national funds from FCT/MCTES (UID/Multi/04378/2019

    The VISIR+ Project – Preliminary results of the training actions

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    Experimental competences allow engineering students to consolidate knowledge and skills. Remote labs are a powerful tool to aid students in those developments. The VISIR remote lab was considered the best remote lab in the world in 2015. The VISIR+ project main goal is to spread VISIR usage in Brazil and Argentina, providing technical and didactical sup- port. This paper presents an analysis of the already prosecuted actions regarding this project and an assessment of their impact in terms of conditioning factors. The overall outcomes are highly positive since, in each Latin American Higher Education Institution, all training actions were successful, the first didactical implementations were designed and ongoing in the current semester. In some cases, instead of one foreseen implementation, there are several. The most statistically conditioning factors which affected the outcomes were the pre-experience with re- mote labs, the pre-experience with VISIR and the training actions duration. The teachers’ per- ceptions that most conditioned their enrollment in implementing VISIR in their courses were related to their consciousness of the VISIR effectiveness to teach and learn. The lack of time to practice and discuss their doubts and the fulfillment of their expectations in the training actions, also affected how comfortable in modifying their course curricula teachers were.info:eu-repo/semantics/acceptedVersio

    Postural Control during the Stroop Test in Dyslexic and Non Dyslexic Teenagers

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    Postural control in quiet stance although simple still requires some cognitive resources; dual cognitive tasks influence further postural control. The present study examines whether or not dyslexic teenagers experience postural instability when performing a Stroop dual task for which their performances are known to be poor. Fifteen dyslexics and twelve non-dyslexics (14 to 17 years old) were recruited from the same school. They were asked to perform three tasks: (1) fixate a target, (2) perform an interference Stroop test (naming the colour or the word rather than reading the word), (3) performing flexibility Stroop task: the subject performed the interference task as in (2) except when the word was in a box, in which case he had to read the word. Postural performances were measured with a force platform. The results showed a main task effect on the variance of speed of body sway only: such variance was higher in the flexibility task than for the other two tasks. No group effect was found for any of the parameters of posture (surface, mediolateral and anteroposterior sway, variance of speed). Further wavelet analysis in the time-frequency domain revealed an increase in the spectral power of the medium frequency range believed to be related to cerebellum control; an accompanying increase in the cancellation time of the high frequency band related to reflexive loops occurred for non-dyslexics only. These effects occurred for the flexibility task and could be due to its high cognitive difficulty. Dyslexics displayed shorter cancellation time for the medium frequency band for all tasks, suggesting less efficient cerebellar control, perhaps of eye fixation and attention influencing body sway. We conclude that there is no evidence for a primary posture deficit in 15 year old teenagers who come from the general population and who were recruited in schools

    Virgo gravitational wave detector: Results and perspectives

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    The Virgo detector reached during the past science run a sensitivity very close to the design one. During the last year the detector has been improved by suspending the main interferometer mirrors with monolithic fibers, with the goal of reducing the thermal noise contribution and testing the new technology. At the same time the design of the next detector improvements are on-going and they will be implemented during the construction of Advanced Virgo

    A survey of clinical features of allergic rhinitis in adults

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    Supplement: "Localization and broadband follow-up of the gravitational-wave transient GW150914" (2016, ApJL, 826, L13)

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    This Supplement provides supporting material for Abbott et al. (2016a). We briefly summarize past electromagnetic (EM) follow-up efforts as well as the organization and policy of the current EM follow-up program. We compare the four probability sky maps produced for the gravitational-wave transient GW150914, and provide additional details of the EM follow-up observations that were performed in the different bands

    Disease-specific and general health-related quality of life in newly diagnosed prostate cancer patients: The Pros-IT CNR study

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    Background: The National Research Council (CNR) prostate cancer monitoring project in Italy (Pros-IT CNR) is an observational, prospective, ongoing, multicentre study aiming to monitor a sample of Italian males diagnosed as new cases of prostate cancer. The present study aims to present data on the quality of life at time prostate cancer is diagnosed. Methods: One thousand seven hundred five patients were enrolled. Quality of life is evaluated at the time cancer was diagnosed and at subsequent assessments via the Italian version of the University of California Los Angeles-Prostate Cancer Index (UCLA-PCI) and the Short Form Health Survey (SF-12). Results: At diagnosis, lower scores on the physical component of the SF-12 were associated to older ages, obesity and the presence of 3+ moderate/severe comorbidities. Lower scores on the mental component were associated to younger ages, the presence of 3+ moderate/severe comorbidities and a T-score higher than one. Urinary and bowel functions according to UCLA-PCI were generally good. Almost 5% of the sample reported using at least one safety pad daily to control urinary loss; less than 3% reported moderate/severe problems attributable to bowel functions, and sexual function was a moderate/severe problem for 26.7%. Diabetes, 3+ moderate/severe comorbidities, T2 or T3-T4 categories and a Gleason score of eight or more were significantly associated with lower sexual function scores at diagnosis. Conclusions: Data collected by the Pros-IT CNR study have clarified the baseline status of newly diagnosed prostate cancer patients. A comprehensive assessment of quality of life will allow to objectively evaluate outcomes of different profile of care
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