Browsing by Issue Date, starting with "2019-01"
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- Adult asthma scores—development and validation of multivariable scores to identify asthma in surveysPublication . Sá-Sousa, Ana; Pereira, Ana Margarida; Almeida, Rute; Araújo, Luís; Couto, Mariana; Jacinto, Tiago; Freitas, Alberto; Bousquet, Jean; Fonseca, João A.One of the questions in epidemiology is the identification of adult asthma in studies. To develop and validate multivariable scores for adult asthma identification in epidemiological studies and to explore cutoffs to rule in/rule out asthma, compared with asthma diagnosed by a physician after clinical examination and diagnostic tests, blinded to the self-administered questions. We analyzed data (n = 711 adults) from a nationwide population-based study. The predictors were self-administered questions identified in a literature review (the Adult Asthma Epidemiological Score [A2 score]) and from the Global Allergy and Asthma Network of Excellence (GA2LEN) questionnaire (the GA2LEN Asthma Epidemiological Score [GA2LEN score]). Scores were developed using exploratory factor analysis. Internal consistency, discriminative power, and diagnostic accuracy were assessed. The A2 score comprises 8 questions (including “Did a physician confirm you had asthma?”) and the GA2LEN score comprises 6 questions (including “Have you ever had asthma?”). Both had high Cronbach α (0.89 and 0.85, respectively, for the A2 score and the GA2LEN score) and good area under the receiver-operating characteristic curve (90.4% and 89.0%). The scoring is the sum of positive answers. Asthma is present (rule in) for scores of 4 or more (specificity, 99.2%; PPV, 93.3% and 91.7%; accuracy, 89.4% and 87.4%, respectively, for the A2 score and the GA2LEN score). Asthma is excluded (rule out) for A2 scores of 0 to 1 and a GA2LEN score of 0 (sensitivity, 93.1%; NPV, 98.2% and 98.0%; accuracy 89.4% and 82.8%, respectively, for the A2 score and the GA2LEN score). These practical scores can be used to rule in/rule out asthma in epidemiological studies and clinical screening/triage settings. They may help physicians in primary care or other specialties to screen patients with asthma using a simple score with a high level of discrimination and to identify the best candidates to be referred for a diagnostic workup. Moreover, their use may contribute to reducing the inconsistencies of operational definitions of asthma across studies and surveys.
- Nutrition education: challenges from a growing digital and social media ecosystemPublication . Costa-Rodrigues, JoãoThe present digital revolution that we are living is making dramatic changes not only in entertainment but especially in education. A few decades ago, entertainment/education was consumed passively, and was created by companies or experts that decided what people should see and learn. Nowadays, everyone can be both a consumer and a creator, and the created contents can virtually reach any people in any place. Another important issue regarding all of this changes is the availability and accessibility of digital media interfaces and devices, especially in children and teenagers. One of the contents that is more likely to be searched in digital media are nutrition-related issues. Brands and marketers have realized it and there is a strong investment in this field. Unfortunately, due to that there is a growing number of digital platforms that offer information about food and nutrition without any scientific background. Even worse, in a significant percentage of cases, the information is created and transmitted without the intervention of nutritionists.
- The influence of the extraction temperature on polyphenolic profiles and bioactivity of chamomile (Matricaria chamomilla L.) subcritical water extractsPublication . Cvetanović, Aleksandra; Švarc-Gajić, Jaroslava; Zeković, Zoran; Jerković, Jelena; Zengin, Gokhan; Gašić, Uroš; Tešić, Živoslav; Mašković, Pavle; Soares, Cristina; Barroso, M. Fátima; Delerue-Matos, Cristina; Đurović, SašaThe main goal of this research was to determine the relationship among chemical structure, bioactivity and temperature of chamomile during subcritical water extraction in isobaric conditions (45 bar) at seven different temperatures (65-210 °C). The influence of temperature on phenolic profiles was defined by UHPLC-HESI-MS/MS. The overall results indicate that the presence of conjugated double bonds, side chains, glucose moiety or ether moiety in molecules influence the efficiency of polyphenols' extraction in subcritical water. In terms of antioxidant activity, the extracts were the most active towards ABTS radicals (IC50 = 7.3-16.8 µg/mL), whereby temperature of 150 °C was optimal. On the other hand, the extracts obtained at 115 °C showed highest cytotoxicity. Inhibition of α-amylase and α-glucosidase was the highest at 65 and 85 °C, i.e. 0.51 and 4.13 mmolAE/g, respectively. Activity against tyrosinase was the highest at 210 °C (17.92 mgKAE/g). The data showed that different non-phenolic compounds may also participate in bio-activities of the extracts.
- Effects and bioaccumulation of gold nanoparticles in the gilthead seabream (Sparus aurata) – Single and combined exposures with gemfibrozilPublication . Barreto, A.; Luis, L.G.; Pinto, E.; Almeida, A.; Paíga, Paula; Santos, Lúcia H.M.L.M.; Delerue-Matos, Cristina; Trindade, T.; Soares, A.M.V.M.; Hylland, K.; Loureiro, S.; Oliveira, M.Gold nanoparticles (AuNPs) are found in a wide range of applications and therefore expected to present increasing levels in the environment. There is however limited knowledge concerning the potential toxicity of AuNPs as well as their combined effects with other pollutants. Hence, the present study aimed to investigate the effects of AuNPs alone and combined with the pharmaceutical gemfibrozil (GEM) on different biological responses (behaviour, neurotransmission, biotransformation and oxidative stress) in one of the most consumed fish in southern Europe, the seabream Sparus aurata. Fish were exposed for 96 h to waterborne 40 nm AuNPs with two coatings - citrate and polyvinylpyrrolidone (PVP), alone or combined with GEM. Antioxidant defences were induced in liver and gills upon both AuNPs exposure. Decreased swimming performance (1600 μg.L-1) and oxidative damage in gills (4 and 80 μg.L-1) were observed following exposure to polyvinylpyrrolidone coated gold nanoparticles (PVP-AuNPs). Generally, accumulation of gold in fish tissues and deleterious effects in S. aurata were higher for PVP-AuNPs than for cAuNPs exposures. Although AuNPs and GEM combined effects in gills were generally low, in liver, they were higher than the predicted. The accumulation and effects of AuNPs showed to be dependent on the size, coating, surface charge and aggregation/agglomeration state of nanoparticles. Additionally, it was tissue' specific and dependent on the presence of other contaminants. Although, gold intake by humans is expected to not exceed the estimated tolerable daily intake, it is highly recommended to keep it on track due to the increasing use of AuNPs.
- Discovery of a New Xanthone against Glioma: Synthesis and Development of (Pro)liposome FormulationsPublication . Alves, Ana; Correia-da-Silva, Marta; Nunes, Claúdia; Campos, João; Sousa, Emília; Silva, Patrícia; Bousbaa, Hassan; Rodrigues, Francisca; Ferreira, Domingos; Costa, Paulo; Pinto, MadalenaFollowing our previous work on the antitumor activity of acetylated flavonosides, a new acetylated xanthonoside, 3,6-bis(2,3,4,6-tetra-O-acetyl-β-glucopyranosyl)xanthone (2), was synthesized and discovered as a potent inhibitor of tumor cell growth. The synthesis involved the glycosylation of 3,6-di-hydroxyxanthone (1) with acetobromo-α-d-glucose. Glycosylation with silver carbonate decreased the amount of glucose donor needed, comparative to the biphasic glycosylation. Xanthone 2 showed a potent anti-growth activity, with GI50 < 1 μM, in human cell lines of breast, lung, and glioblastoma cancers. Current treatment for invasive brain glioma is still inadequate and new agents against glioblastoma with high brain permeability are urgently needed. To overcome these issues, xanthone 2 was encapsulated in a liposome. To increase the well-known low stability of these drug carriers, a proliposome formulation was developed using the spray drying method. Both formulations were characterized and compared regarding three months stability and in vitro anti-growth activity. While the proliposome formulation showed significantly higher stability, it was at the expense of losing its biocompatibility as a drug carrier in higher concentrations. More importantly, the new xanthone 2 was still able to inhibit the growth of glioblastoma cells after liposome formulation.
- Síndrome visual do computador: intervenção para a redução dos fatores de risco e avaliação do seu impactoPublication . Cardoso, Bárbara Sofia Marques; Rodrigues, Matilde; Mateus, CatarinaA Síndrome Visual do Computador (SVC) descreve um conjunto de problemas oculares e visuais que resultam do uso prolongado de ecrãs de visualização. A sua severidade e prevalência tem sido relacionada com fatores individuais, hábitos de visualização e características do posto de trabalho. Apesar de vários estudos terem analisado a relação entre a ocorrência da SVC e potenciais fatores de risco, poucos estudaram o impacto de uma intervenção ergonómica na redução dos sintomas. O presente estudo tem como objetivo elaborar e implementar um programa de intervenção para a redução dos sintomas relacionados com a SVC. Foram envolvidos no estudo 84 colaboradores de uma instituição de caridade e assistência social. A intervenção abrangeu ações de formação a todos os colaboradores, entrega de panfleto informativo e de uma embalagem de lágrimas artificiais, tratamento ortóptico para a insuficiência de convergência e correção dos postos de trabalho. Para descrever aspetos gerais, bem como para avaliar a eficácia da intervenção, foi aplicado um questionário em três momentos: Pré-intervenção; Pósintervenção Momento 1 e Pós-intervenção Momento 2. Este incluiu questões relacionadas com aspetos pessoais, características do posto de trabalho, hábitos de visualização, uma escala para a avaliação da SVC. No momento Pré-intervenção foi aplicado o questionário completo, enquanto que nos restantes momentos foi aplicado apenas a escala de avaliação da SVC e o questionário com a escala para avaliação do desconforto musculoesquelético. Adicionalmente, foi aplicado no último momento um questionário para analisar a perceção dos sujeitos sobre o impacto da intervenção. Verificaram-se alterações nos comportamentos adotados pelos sujeitos, nomeadamente no ajuste do posto de trabalho e na realização de descanso visual. A severidade e prevalência da SVC diminuiu, apesar de não se terem verificado diferenças significativas entre os 3 momentos. Em relação aos sintomas musculoesqueléticos, referidos na literatura como estando associados à SVC, verificaram-se melhorias significativas ao nível da parte superior das costas e do pescoço ao final do dia de trabalho. Este estudo sugere que um programa de intervenção ergonómica apresenta vantagens para a saúde dos trabalhadores, promovendo a diminuição dos sintomas visuais e musculoesqueléticos.
- Impacto do envelhecimento na amplitude de movimento do membro superior: comparação entre o método tradicional e o wrist evaluation systemPublication . Freitas, Artur Henrique Rodrigues de; Fernandes, Ângela; Restivo, Maria TeresaObjetivo: O objetivo deste estudo é compreender o impacto do envelhecimento na amplitude de movimento do punho e antebraço, e comparar a avaliação através do uso do método tradicional e da utilização do sistema Wrist Evalution System. Método: Este estudo pode ser classificado como do tipo quantitativo, observacional, analítico e transversal. A amostra foi constituída por 115 participantes, sendo que posteriormente foi dividida em três grupos etários. Um primeiro grupo constituído por 44 jovens, dos 18 aos 25 anos, um segundo grupo constituído por 34 indivíduos entre os 26 e os 59 anos, e um terceiro grupo constituído por 37 indivíduos com mais de 60 anos. A avaliação realizou-se num único momento, recorrendo-se a dois métodos: o método tradicional, através do goniómetro universal e do inclinómetro, e um segundo, um sistema designado por Wrist Evaluation System. Em ambos os métodos de avaliação e nos três grupos etários, foram avaliados os valores de amplitude de movimento de flexão, extensão, desvio radial e cubital do punho e pronação e supinação do antebraço. Resultados: Verificaram-se correlações significativas da idade e número de horas de atividade física por semana com as amplitudes de movimento avaliadas, independentemente do método utilizado. Quando comparados os diferentes grupos, observaram-se diferenças significativas entre grupo mais velho e o grupo mais novo da amostra para a maioria dos movimentos. Entre os instrumentos de avaliação, o Wrist Evaluation System apresentou valores significativamente inferiores nos movimentos de supinação do antebraço e extensão do punho e superiores nos movimentos desvio radial e cubital do punho e na pronação do antebraço. Conclusão: Através deste estudo, conclui-se que o envelhecimento tem um impacto negativo na amplitude de movimento, e que há diferenças significativas entre os dois métodos em todos os movimentos
- Measurements of retinal fluid by oct leakage in diabetic macular edema: A biomarker of visual acuity response to treatmentPublication . Santos, Ana Rita; Alves, Dalila; Santos, Torcato; Figueira, João; Rufino, Silva; Cunha-Vaz, José G.Optical coherence tomography leakage changes after anti-vascular endothelial growth factor treatment of diabetic macular edema, identifying the degree of decrease in retinal fluid in the outer layers of the retina is a more robust biomarker of BCVA recovery than central retinal thickness, disorganization of the inner retinal layer, or ellipsoid zone disruption changes.
- Aggregation of Consumers and Producers in a Community with different Clustering MethodsPublication . Silva, Cátia; Faria, Pedro; Vale, Zita; Starzacher, NikolausThe consumer concept is shaping up as the grid is improving to a smart way. Moving from an actor with little information about what was happening in the energy market, to player with an active and important role in its management. The term prosumer will revolutionize the way the electrical system operates. The possibility of the participation of distributed small-scale energy resources in the network infrastructure changes the current management model. The authors propose a model that optimally associates all concepts. Scheduling, aggregation and compensation are the main phases that compose this model. In this paper, the author focusses only on the second, being the main goal compare between being a consumer, a producer or a prosumer in this method. In this way, two partitional clustering methods were used, testing different k clusters.
- Electric Water Heater Modeling, DR Approaches Analysis and Study of Consumer Comfort for Demand ResponsePublication . Ahmed; Faria, Pedro; Vale, ZitaWith the smart energy management system household residential appliances is able to participate in the demand response events. To reduce peak load demand and complexities in the local infrastructure DR can play an important role now a days. This paper presents a study and analysis of several papers on residential EWH DR modeling and implementation. It shows an overview of analysis of the most used and recent DR models for EWH. It also shows the analysis of the used methods to model this and the used approach in several papers. Additionally, the discussed consumer comforts and obtainable benefits in several papers by participating in DR events is also shown here. The study and analysis in this paper will contribute to the future research and encourage the end users to participate in households DR events.