Envelhecimento : activo ? bem sucedido ? saudável ? possíveis coordenadas de análise…

Que concepção ou visão do envelhecimento poderá guiar a formulação de políticas, a actuação e a investigação ? Diversos termos têm surgido nas últimas décadas, alguns correspondendo a propostas conceptuais claramente estruturadas, outros nem tanto... Abordar-se-ão aqui alguns dos mais divulgados – envelhecimento saudável, envelhecimento bem sucedido, envelhecimento activo –, discutindo as suas potencialidades e limites. Adoptando como referência uma perspectiva de promoção da saúde, tal como decorre da Carta de Ottawa (1986), termina-se com uma proposta de critérios a ter em conta numa conceptualização de envelhecimento.Which understanding or vision of ageing should guide us in policy making, action and research ? In the last decades, several concepts and frameworks have been proposed. This article discusses some of them – healthy aging, successful aging, active ageing – emphasising their potential and limits. Adopting a health promotion approach consistent with the Ottawa Charter (1986), it concludes with a proposal of criteria to be considered in analysing or developing an ageing framework and vision

Hemodynamic evaluation of the right portal vein in healthy dogs of different body weights

<p>Abstract</p> <p>Background</p> <p>Doppler ultrasonography is an important tool for evaluating hepatic portal hemodynamics. However, no study in dogs of different body weights, in the range encountered in routine clinical veterinary practice, has been reported. It can be difficult to obtain an ideal insonation angle when evaluating the main portal vein, so evaluation of the right portal vein branch has been described in humans as an alternative. The aim of this study was to analyze, through Doppler ultrasonography, the hemodynamics in the right portal vein branch in dogs of different body weights.</p> <p>Methods</p> <p>Thirty normal dogs were divided in three groups by weight, in order to establish normal values for mean velocity, flow volume and portal congestion index of the right portal vein branch by means of Doppler ultrasonography.</p> <p>Results</p> <p>In all dogs ideal insonation angles were obtained for the right portal vein branch. The average velocity was similar in the three groups, but the portal congestion index and the flow volume differed, showing that the weight of the dog can influence these values.</p> <p>Conclusion</p> <p>Doppler ultrasonography for the evaluation of flow in the right branch of the portal vein could be a viable alternative, or complement, to examining the main vessel segment. This is especially so in those animals in which an ideal insonation angle for examination of the main portal vein is hard to obtain. In addition, the weight of the dog must be considered for the correct evaluation of the portal system hemodynamics, particularly for portal blood flow and the congestion index.</p

Sowing wildflower meadows in Mediterranean peri-urban green areas to promote grassland diversity

Introduction: The increase of urban areas and their infrastructure network is homogenizing the landscape and threatening biodiversity and ecosystems functions and services. Wildflower meadows have a high biodiversity value and can prosper in degraded areas dominated by nitrophilous species, making them suitable to be used in peri-urban and urban areas to promote local flora, create habitat for pollinators and other small fauna, and increase overall biodiversity. Moreover, the application of wildflowers seed mixes suitable for rehabilitating anthropized environments should be restricted to native species of regional origin, and the results properly monitored. However, thorough monitoring of seed mixes evolution is uncommon. This study evaluates the effectiveness of a seed mix of wild native species developed to promote grassland diversity in Mediterranean peri-urban areas. Methods: The study was divided into two sequential phases. Firstly, a preparatory phase consisted in developing two seed mixes and sowing them (autumn 2016) in ex-situ plots (three plots of 5 × 2 m2 per mix) at an experimental field to choose the one with the best performance. The second phase consisted of the in-situ application (autumn 2018) of the chosen seed mix by sowing 14 plots (10 × 2 m2) in pocket parks distributed along pedestrian trails of South Portugal. All plots were monitored through floristic surveys for two springs (ex-situ trials: 2017 and 2018; in-situ trials: 2019 and 2020). Results: All sowed species germinated in the in-situ plots over the first 2  years. The seed mix application positively contributed to the floristic community, generating a significant increase in the total species richness, diversity, evenness, and vegetation cover. The seed mix establishment did not require watering nor soil fertilizing and the mowing frequency was low (once in late spring), contributing to sustainable and low-cost management of these green areas. Discussion: The tested seed mix promoted native flora diversity rapidly and seems suitable for use in peri-urban context under identical climate conditions. Given the small number of native seed mixes tested in the Mediterranean, this study represents a contribution toward improved management standards of native flora diversity in Mediterranean green urban and peri-urban areas.info:eu-repo/semantics/publishedVersio

Identification of protein-coding and non-coding RNA expression profiles in CD34+ and in stromal cells in refractory anemia with ringed sideroblasts

<p>Abstract</p> <p>Background</p> <p>Myelodysplastic syndromes (MDS) are a group of clonal hematological disorders characterized by ineffective hematopoiesis with morphological evidence of marrow cell dysplasia resulting in peripheral blood cytopenia. Microarray technology has permitted a refined high-throughput mapping of the transcriptional activity in the human genome. Non-coding RNAs (ncRNAs) transcribed from intronic regions of genes are involved in a number of processes related to post-transcriptional control of gene expression, and in the regulation of exon-skipping and intron retention. Characterization of ncRNAs in progenitor cells and stromal cells of MDS patients could be strategic for understanding gene expression regulation in this disease.</p> <p>Methods</p> <p>In this study, gene expression profiles of CD34⁺cells of 4 patients with MDS of refractory anemia with ringed sideroblasts (RARS) subgroup and stromal cells of 3 patients with MDS-RARS were compared with healthy individuals using 44 k combined intron-exon oligoarrays, which included probes for exons of protein-coding genes, and for non-coding RNAs transcribed from intronic regions in either the sense or antisense strands. Real-time RT-PCR was performed to confirm the expression levels of selected transcripts.</p> <p>Results</p> <p>In CD34⁺cells of MDS-RARS patients, 216 genes were significantly differentially expressed (q-value ≤ 0.01) in comparison to healthy individuals, of which 65 (30%) were non-coding transcripts. In stromal cells of MDS-RARS, 12 genes were significantly differentially expressed (q-value ≤ 0.05) in comparison to healthy individuals, of which 3 (25%) were non-coding transcripts.</p> <p>Conclusions</p> <p>These results demonstrated, for the first time, the differential ncRNA expression profile between MDS-RARS and healthy individuals, in CD34⁺cells and stromal cells, suggesting that ncRNAs may play an important role during the development of myelodysplastic syndromes.</p

Bottom-trawling fisheries influence on standing stocks, composition, diversity and trophic redundancy of macrofaunal assemblages from the West Iberian Margin

Bottom-trawling fisheries operating in Portugal (West Iberian Margin) impose one of the largest footprints per unit of biomass landed in European waters at depths greater than 200 m, affecting the seafloor integrity and the associated benthic fauna. To investigate how trawling pressure is affecting the macrofaunal assemblages, we compared the standing stock (abundance and biomass), community structure and taxonomical and trophic diversity in areas subjected to varying trawling pressure along the SW Portuguese upper slope, between 200 and 600 m. In addition to trawling pressure, several environmental variables, namely depth, grain size and organic matter, were correlated with the biological component, which suggest that the longstanding trawling pressure presents cumulative effects to the habitat heterogeneity known to characterise the West Iberian Margin fauna. Furthermore, our results showed a depletion of macro-infaunal abundances in both the fishing ground and the adjacent area (up to 3 times lower), when compared to the area not trawled. The observed decrease in abundance with increasing trawling pressure was also associated with a loss of species and trophic richness, but univariate diversity indices related with community structure (i.e. Shannon-Wiener index, Pielou's evenness) failed to detect consistent differences across areas. Also observed was a decrease in the number of taxa – trophic guilds combinations of the core assemblage (i.e. characteristic, dominant or frequent taxa) with increasing trawling pressure. We suggest that, in disturbed sediments, the lower functional redundancy resulting from the loss of species within most feeding guilds increases the vulnerability of trophic interactions and therefore of the whole assemblage to further increases in natural and anthropogenic disturbance or their synergistic effects.publishe

Microglial Sirtuin 2 shapes long-term potentiation in hippocampal slices

Copyright © 2020 Sa de Almeida, Vargas, Fonseca-Gomes, Tanqueiro, Belo, Miranda-Lourenço, Sebastião, Diógenes and Pais. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Microglial cells have emerged as crucial players in synaptic plasticity during development and adulthood, and also in neurodegenerative and neuroinflammatory conditions. Here we found that decreased levels of Sirtuin 2 (Sirt2) deacetylase in microglia affects hippocampal synaptic plasticity under inflammatory conditions. The results show that long-term potentiation (LTP) magnitude recorded from hippocampal slices of wild type mice does not differ between those exposed to lipopolysaccharide (LPS), a pro-inflammatory stimulus, or BSA. However, LTP recorded from hippocampal slices of microglial-specific Sirt2 deficient (Sirt2-) mice was significantly impaired by LPS. Importantly, LTP values were restored by memantine, an antagonist of N-methyl-D-aspartate (NMDA) receptors. These results indicate that microglial Sirt2 prevents NMDA-mediated excitotoxicity in hippocampal slices in response to an inflammatory signal such as LPS. Overall, our data suggest a key-protective role for microglial Sirt2 in mnesic deficits associated with neuroinflammation.This study was supported by Santa Casa da Misericórdia de Lisboa (MB37-2017), GAPIC Research Program of the University of Lisbon Medical School (n° 2014002 and n° 2015028) and the following doctoral grants: PD/BD/128091/2016, SFRH/BD/118238/2016, PD/BD/114337/2016, and PD/BD/1144- 41/2016.info:eu-repo/semantics/publishedVersio

XRD and FTIR analysis of Ti–Si–C–ON coatings for biomedical applications

Ti–Si–C–ON films were deposited by DC reactive magnetron sputtering using different partial pressure ratio of oxygen (pO2) and nitrogen (pN2). Compositional analysis revealed the existence of three different growth zones for the films; (I) N/Ti = 2.1 (high atomic ratio) and low oxygen content; (II) 0.76 < N/Ti < 2.1 (intermediate atomic ratio) and (III) N/Ti ≤ 0.12 (low ratio) and high oxygen content. For high N/Ti atomic ratio (N/Ti = 2.1) the XRD pattern exhibits reflections that correspond to a mixture of two different phases: a metallic-like Ti and a fcc NaCl type structure. Its electrical resistivity presents a metallic character and, consequently, has high infrared reflectivity. For the intermediate N/Ti ratio (0.76 < N/Ti < 2.1), the films crystallize in a B1-NaCl crystal structure typical for TiC0.2N0.8. Their FTIR spectra present C–N modes, besides the TiN ones, that indicate a progressive substitution of nitrogen by carbon atoms with increasing oxygen content (and lowering N/Ti ratio). For the highest oxygen content (and lower N/Ti ratio) the presence of the Ti–O–Ti stretching mode shows the formation of highly resistive Ti–O compounds consistent with the semiconductor character of this film. Biofilm formation as well as material cytotoxicity seemed to be related with the presence of the Ti

Photoinactivation of bacterial and fungal planktonic/biofilm forms using the combination of a porphyrinic formulation with potassium iodide

Antimicrobial photodynamic therapy (aPDT) is a promising approach against multidrug-resistant microorganisms. In this work, we accessed the photodynamic efficiency of an affordable formulation composed of five cationic porphyrins (FORM) and its combined effect with potassium iodide (KI) on a large spectrum of microorganisms. For this purpose, the aPDT assays were conducted with FORM alone and FORM + KI on planktonic and biofilm forms of Gram(+) (Staphylococcus aureus) and Gram(−) (Escherichia coli) bacteria and of the yeast Candida albicans. The results obtained indicate that FORM, at low concentrations (0.5–5.0 μM), had an efficient photodynamic action on the planktonic forms of E. coli, S. aureus, and C. albicans. Moreover, the combination of FORM with KI improved the photodynamic action of this PS, promoting microbial inactivation with lower PS concentrations and treatment time. The combination of FORM + KI was also extremely efficient in the destruction of bacterial and fungal biofilms. This outstanding effect may be due to the action of longer-lived iodine reactive species produced by the reaction of KI with the ROS generated by FORM during the aPDT treatment.info:eu-repo/semantics/publishedVersio

Identification of a micropeptide and multiple secondary cell genes that modulate <i>Drosophila</i> male reproductive success

Even in well-characterized genomes, many transcripts are considered noncoding RNAs (ncRNAs) simply due to the absence of large open reading frames (ORFs). However, it is now becoming clear that many small ORFs (smORFs) produce peptides with important biological functions. In the process of characterizing the ribosome-bound transcriptome of an important cell type of the seminal fluid-producing accessory gland of Drosophila melanogaster, we detected an RNA, previously thought to be noncoding, called male-specific abdominal (msa). Notably, msa is nested in the HOX gene cluster of the Bithorax complex and is known to contain a micro-RNA within one of its introns. We find that this RNA encodes a "micropeptide" (9 or 20 amino acids, MSAmiP) that is expressed exclusively in the secondary cells of the male accessory gland, where it seems to accumulate in nuclei. Importantly, loss of function of this micropeptide causes defects in sperm competition. In addition to bringing insights into the biology of a rare cell type, this work underlines the importance of small peptides, a class of molecules that is now emerging as important actors in complex biological processes

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

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