In vivo antioxidant activity of phenolic compounds: facts and gaps

Background: Numerous diseases have been related with free radicals overproduction and oxidative stress. Botanical preparations possess a multitude of bioactive properties, including antioxidant potential, which has been mainly related with the presence of phenolic compounds. However, the mechanisms of action of these phytochemicals, in vivo effects, bioavailability and bio-efficacy still need research. Scope and Approach: The present report aims to provide a critical review on the aspects related with the in vivo antioxidant activity of phenolic extracts and compounds from plant origin. Key findings: Biological functions beyond the human metabolism were discussed, comparing in vivo vs. in vitro studies, as also focusing the conditioning factors for phenolic compounds bioavailability and bio-efficacy. Furthermore, an upcoming perspective about the use of phytochemicals as life expectancy promoters and anti-aging factors in human individuals was provided. Conclusions: Overall, and despite all of those advances, the study of the biological potential of numerous natural matrices still remains a hot topic among the scientific community. In fact, the available knowledge about the responsible phytochemicals for the biological potential, their mechanisms of action, the establishment of therapeutic and prophylactic doses, and even the occurrence of biochemical inter-relations, is considerable scarce.

Alimentação e miopia

Dissertação de mestrado em Optometria Avançada

Synthesis of polyhydroxylated compounds from Derythrose: enzymatic inhibition studies

Dissertação de mestrado em Química Medicinal

Trans-cultural aspects of social anxiety disorder and related conditions: a Brazilian case series and a review of international clinical studies

Cross-cultural studies have much to teach clinicians and researchers alike about psychopathology in general and about social anxiety disorder (SAD) in particular. Unfortunately, little is known about the degree and the mechanisms through which cultural environment may influence clinical manifestations of SAD. OBJECTIVE: Our objective was to identify culture-related clinical patterns in SAD and related disorders. METHODS: We described socio-demographic and clinical characteristics of a sample of 62 adult outpatients with SAD seen at a university clinic for anxiety and depressive disorders in Rio de Janeiro, Brazil, and compared them with those reported in clinical samples from North America, Europe, Asia and Oceania identified through a systematic review in Medline, PsychINFO, and LILACS. RESULTS: Our comparison of trans-cultural features of SAD lends partial support to Heimberg's (1997) contention that the majority of socio-demographic features and symptoms of this disorder are relatively independent of geographic and cultural differences. CONCLUSION: Patients with SAD were almost universally characterized by: 1) a predominance of males in clinical samples; 2) early onset of the disorder; 3) high educational attainment; and 4) great frequency of comorbidities.

Imidazo-benzocrown ether functionalised amino acids: synthesis and fluorimetric chemosensing studies with metal cations

Comunicação em painel - P59

Chemical composition, antioxidant activity and bioaccessibility studies in phenolic extracts of two Hericium wild edible species

Mushrooms are rich sources of bioactive compounds such as phenolic acids. When ingested, these molecules have to be released from the matrix to be transformed/absorbed by the organism, so that they can exert their bioactivity. Several in vitro methodologies have been developed in order to evaluate the bioavailability of bioactive compounds. Herein, two Hericium species were analyzed for their chemical composition and antioxidant activity. Furthermore, an in vitro digestion of the mushrooms and mushroom phenolic extracts was performed, and the digested samples were also submitted to antioxidant activity evaluation in order to evaluate the bioaccessibility of the phenolic acids identified in the samples. Hericium species showed similar chemical profiles (except for tocopherols), varying only in the concentration of the compounds. The phenolic extracts revealed higher antioxidant activity than the in vitro digested samples, meaning that this process decrease the antioxidant properties of the extract/mushroom. Nevertheless, phenolic acids were found in the digested samples, meaning that those molecules are bioaccessible.

Synthesis, antiangiogenesis evaluation and molecular docking studies of 1-Aryl-3-[(thieno[3,2-b]pyridin-7-ylthio)phenyl]ureas: Discovery of a new substitution pattern for type II VEGFR-2 Tyr kinase inhibitors

The synthesis and biological evaluation of novel 1-aryl-3-[2-, 3- or 4-(thieno[3,2-b]pyridin-7-ylthio)phenyl]ureas 3, 4 and 5 as VEGFR-2 tyrosine kinase inhibitors, are reported. The 1-aryl-3-[3-(thieno[3,2-b]pyridin-7-ylthio)phenyl]ureas 4a-4h, with the arylurea in the meta position to the thioether, showed the lowest IC50 values in enzymatic assays (10-206 nM), the most potent compounds 4d-4h (IC50 10-28 nM) bearing hydrophobic groups (Me, F, CF3 and Cl) in the terminal phenyl ring. A convincing rationalization was achieved for the highest potent compounds 4 as type II VEGFR-2 inhibitors, based on the simultaneous presence of: (1) the thioether linker and (2) the arylurea moiety in the meta position. For compounds 4, significant inhibition of Human Umbilical Vein Endothelial Cells (HUVECs) proliferation (BrdU assay), migration (wound-healing assay) and tube formation were observed at low concentrations. These compounds have also shown to increase apoptosis using the TUNEL assay. Immunostaining for total and phosphorylated (active) VEGFR-2 was performed by Western blotting. The phosphorylation of the receptor was significantly inhibited at 1.0 and 2.5 microM for the most promising compounds. Altogether, these findings point to an antiangiogenic effect in HUVECs.

Preservation of vernacular schist masonry farm walls

This paper complements the information presented at the CIAV2013 on vernacular build- ings in northern Portugal, and addresses the topic of masonry walls in the rural areas of the northwestern Portuguese coastline. These walls are structural schist masonry constructions, built using ancient tech- niques and locally available resources. The result is a territory built for agricultural exploration, and a landscape imprinted with past social hierarchies and structures. Using the information gathered by the fieldwork study, the paper will present studies on masonry walls with different morphologies, construction materials and building techniques employed. The information presented aims to contribute to enlighten researchers and technicians about these building specificities, to increase the scarce available literature about schist’s potential as construction material, and to enhance the importance of the cultural value of this particular kind of heritage.

Experimental and numerical studies of hybrid PCM embedded in plastering mortar for enhanced thermal behaviour of buildings

This paper proposes a methodology for improvement of energy efficiency in buildings through the innovative simultaneous incorporation of three distinct phase change materials (here termed as hybrid PCM) in plastering mortars for façade walls. The thermal performance of a hybrid PCM mortar was experimentally evaluated by comparing the behaviour of a prototype test cell (including hybrid PCM plastering mortar) subjected to realistic daily temperature profiles, with the behaviour of a similar prototype test cell, in which no PCM was added. A numerical simulation model was employed (using ANSYS-FLUENT) to validate the capacity of simulating temperature evolution within the prototype containing hybrid PCM, as well as to understand the contribution of hybrid PCM to energy efficiency. Incorporation of hybrid PCM into plastering mortars was found to have the potential to significantly reduce heating/cooling temperature demands for maintaining the interior temperature within comfort levels when compared to normal mortars (without PCM), or even mortars comprising a single type of PCM.

In vitro and in vivo studies of temozolomide loading in zeolite structures as drug delivery systems for glioblastoma

Zeolites Y (faujasite) and MOR (mordonite) were used as hosts for temozolomide (TMZ), a current good-standard chemotherapeutic agent used in the treatment of glioblastoma brain tumors. TMZ was loaded into zeolites by liquid-phase adsorption at controlled pH. FTIR, 1H NMR, MS, SEM, UV/vis and chemical analysis demonstrated the successful loading of TMZ into zeolite hosts. The hydrolysis of TMZ in MTIC (TMZ metabolite) after the preparation of drug delivery systems (DDS) was observed in simulated body fluid. The effect of zeolites and DDS were evaluated on the viability of glioblastoma cell lines. Unloaded Y zeolite presented toxicity to cancer cells in contrast to MOR. In accordance, the best results in potentiation of the TMZ effect was obtained with MOR. We found that mordonite loaded with 0.026 mmol of TMZ was able to decrease the half maximal inhibitory concentrations (IC50) at least 3-fold in comparison to free temozolomide both in vitro and in vivo.

Géneros textuais e práticas de sucesso no 1º ciclo do ensino básico

Tese de Doutoramento em Estudos da Criança (Área do Conhecimento em Estudos da Língua Portuguesa)

Looking for mechanisms regulating lung growth in CDH: rat and human studies

Tese de Doutoramento em Ciências da Saúde

Effects of bariatric surgery on the central nervous system and eating behavior in humans: a systematic review on the neuroimaging studies

INTRODUCTION: Neuroimaging studies suggest that obese people might show hyperactivity of brain areas regarding reward processing, and hypoactivity of brain areas concerning cognitive control, when exposed to food cues. Although the effects of bariatric surgery on the central nervous system and eating behavior are well known, few studies have used neuroimage techniques with the aim of investigating the central effects of bariatric surgery in humans. OBJECTIVES: This paper systematically and critically reviews studies using functional neuroimaging to investigate changes on the patterns of activation of central areas related to the regulation of eating behavior after bariatric surgery. METHOD: A search on the databases Medline, Web of Science, Lilacs and Science Direct on Line, was conducted in February 2013, using the keywords "Neuroimaging", "Positron-Emission Tomography", "Magnetic Resonance Imaging", "Gastric Bypass", "Gastroplasty", "Jejunoileal Bypass", "Bariatric Surgery". RESULTS: Seven manuscripts were included; the great majority studied the central effects of Roux en Y gastric bypass, using positron emission tomography or functional magnetic resonance. CONCLUSIONS: Bariatric surgery might normalize the activity of central areas concerned with reward and incentive salience processing, as the nucleus accumbens and mesencephalic tegmental ventral area, as well as circuitries processing behavioral inhibition, as the dorsolateral prefrontal cortex.

Psychometric properties of assessment instruments for autism spectrum disorder: a systematic review of Brazilian studies

Objective To systematically review the scientific literature on the psychometric properties of international instruments for the assessment of autism spectrum disorder (ASD) in the Brazilian population. Methods A search of bibliographic references was conducted in six electronic databases: PsycINFO, PubMed, IndexPsi, Lilacs, Capes (theses and dissertations) and SciELO. The studies were selected by two independent researchers. Results The procedure identified 11 studies of the Brazilian population that encompassed six ASD assessment tools. Given the information provided, the adaptation of the M-CHAT, a screening instrument, was the best conducted. All steps of the adaptation process were described and the changes made to the final version of the instrument were presented, which was not addressed in other studies. In terms of reliability, all of the instruments that assessed internal consistency showed adequate values. In addition, the ADI-R and the CARS adaptations also satisfactorily contemplated inter-rater reliability and test-retest indices, respectively. Finally, all studies aiming to validate instruments showed evidence of validity and sensitivity, and specificity values above 0.90 were observed in the ASQ, ADI-R and ABC. Conclusion Considering both the psychometric aspects and the copyright information, the screening instrument that currently appears to be best indicated for clinical and research use is the M-CHAT. It was also noticed that there are still no specific ASD diagnostic tools available for use in Brazil. This lack of diagnostic instruments consists in a critical situation for the improvement of clinical practice and the development of research in this area.

Cultural studies as the new humanities

The purpose of this study is to argue that Cultural Studies may be regarded as the new humanities. Cultural Studies focus on ethnic, post-colonial, communication, anthropological, ethnographic and feminist studies, and only ‘very marginally’ have they shown an interest in literature and literary studies (Aguiar & Silva, 2008). But those fields, which ‘Social Science’ rather than the ‘Arts’ have invested in (Ibid., p. 254), are the touchstone of modernity. Today, the concept we have of humankind is, to a large extent, played out in these areas. The questioning of both humankind and modernity has as backdrop the technologically-driven shift of culture from word to image (Martins, 2011 a). My proposal takes into account this debate, while underscoring how Cultural Studies are engaged in what is current and contemporary, which means, in the present and everyday life.