Browsing by Issue Date, starting with "2021-04"
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- Intranasal drug delivery for treatment of Alzheimer's diseasePublication . Fonseca, Leonor Cancela; Lopes, Joao; Vieira, Joao; Viegas, Claudia; Oliveira, Claudia S.; Hartmann, Rafael P.; Fonte, PedroThe Alzheimer's disease is a neurodegenerative condition with severe consequences interfering with patient quality of life. It is characterized as a progressive and irreversible brain disorder hampering memory and thinking, affecting the capacity to perform daily tasks leading to physical and cognitive incapacitation. The conventional treatment occurs by the oral route, but it presents relevant drawbacks such as low bioavailability, fast metabolism, limited brain exposure, and undesirable side effects. The intranasal route has been proposed as a promising alternative to deliver drugs and improve the Alzheimer's disease treatment. Still, there is not a clear alternative delivery system available in the market with advantageous bioavailability and safety. The aim of this review is to perform an overview on the strategies for drug intranasal delivery for Alzheimer's disease treatment. The advantages and disadvantages of this delivery route and the delivery systems developed so far are discussed. A special focus is given on the use of permeation enhancers, the types of intranasal drug delivery devices, as well as possible toxicity concerns.
- Dynamics in cultural spaces in the historic center of Portimão, PortugalPublication . Rodrigues, Ana Maria; Pires Rosa, Manuela; Rebelo, EfigénioO objetivo deste estudo consiste na construção de indicadores referentes ao desempenho dos espaços culturais da cidade de Portimão, Algarve, Portugal, que se encontram inseridos numa rota pedonal, a Rota Turística Acessível de Portimão. Trata-se do Museu de Portimão, espaço cultural que expressa a história da indústria conserveira local, e do Teatro Tempo, localizado num edifício também ele histórico, onde se dinamizam atividades na área da representação. Ambos os edifícios consistem em objetos arquitetónicos com valor patrimonial e reabilitados para espaços culturais. A metodologia aplicada carateriza-se por uma base teórica, pela recolha e análise de dados quantitativos. O conhecimento teórico advém de uma revisão de literatura, em áreas e.g.: turismo cultural, turismo acessível, património e reabilitação urbana. Os dados quantitativos são provenientes da recolha de dados dos espaços culturais Teatro Tempo e Museu de Portimão: número de visitantes/espectadores e número de sessões e atividades desde 2008-2018. Com este estudo pode-se concluir que os espaços culturais Museu de Portimão e Teatro Tempo são usufruídos não só pelos residentes, mas também por visitantes, na cidade de Portimão. A presente análise defende a importância do investimento na reabilitação urbana, na valorização patrimonial e nos espaços culturais para a construção de um turismo cultural acessível e sustentável.
- Paleoenvironments and human adaptations during the Last Glacial Maximum in the Iberian Peninsula: A reviewPublication . Cascalheira, João; Alcaraz-Castano, Manuel; Alcolea-Gonzalez, Javier; Andres-Herrero, Maria de; Arrizabalaga, Alvaro; Tortosa, J. Emili Aura; Garcia-Ibaibarriaga, Naroa; Iriarte-Chiapusso, Maria-JoseThe Iberian Peninsula is considered one of the most well-suited regions in Europe to develop studies on the relationship between environmental changes and human adaptations across the Late Pleistocene. Due to its southwesternmost cul-de-sac position and eco-geographical diversity, Paleolithic Iberia was the stage of cyclical cultural/technological changes, linked to fluctuations in climate and environments, human demographics, and the size, extension, and type of social exchange networks. Such dynamics are particularly evident during the Last Glacial Maximum (LGM) timeframe, with a series of innovations emerging in the archaeological record, marking the transitions between the traditionally defined Gravettian, Proto-Solutrean, Solutrean, and Magdalenian technocomplexes. Stemming from a workshop organized in Erlangen in 2019 on ?The Last Glacial Maximum in Europe - state of knowledge in Geosciences and Archaeology?, this paper presents, in the first part, an updated review on the paleoenvironments and human adaptations across four macro-regions (Northern, Inland, Mediterranean, and Western Atlantic Fa?ade) in Iberia during the LGM; and, in a second part, a discussion on the pronounced interregional variability, unresolved research questions, and the most promising research topics for future studies.
- Nanoencapsulation as a novel delivery approach for therapeutic applications of gla-rich protein (GRP)Publication . Araújo, Nuna; Viegas, Carla; Pontes, Jorge Filipe; Marreiros, Catarina; Raimundo, Pedro; Macedo, Anjos L.; Alves de Matos, António; Grenha, Ana; Vermeer, Cees; Simes, DinaGla rich protein (GRP) is a vitamin K dependent protein, shown to function as an inhibitor of pathological calcification and as an anti-inflammatory agent, with potential therapeutic use for age-related diseases such as osteoarthritis (OA) [1,2]. OA is a leading cause of disability and morbidity in the older population and constitutes a major world wide challenge for our health system. Presently, there are no drugs approved that can prevent, stop, or even restrain progression of OA. GRP has been shown to be able to lower inflammation and mineralisation processes in the articular tissue. Chitosan/tripolyphosphate (TPP) nanoparticles were selected for this study due to their biocompatibility, biodegradability and capacity to overcome the problem of low solubility of GRP in physiological conditions. This study aims to produce and characterise chitosan/TPP nanoparticles as GRP-delivery vehicles and test its anti-inflammatory potential in human macrophages.
- Out-of-hospital cardiac arrest in the Algarve region of Portugal: a retrospective registry trial with outcome dataPublication . Carvalho, Nuno Mourão; Martins, Cláudia; Cartaxo, Vera; Marreiros, Ana; Justo, Emília; Raposo, Carlos; Binnie, AlexandraBackground and importanceOut-of-hospital cardiac arrest is a leading cause of death in Europe. An understanding of region-specific factors is essential for informing strategies to improve survival. DesignThis retrospective observational study included all out-of-hospital cardiac arrest patients attended by the Emergency Medical Service of the Algarve in 2019. Outcome data were derived from hospital records. Main resultsIn 2019, there were 850 out-of-hospital cardiac arrests treated with cardiopulmonary resuscitation in the Algarve, representing a population incidence of 189/100 000. Return of spontaneous circulation occurred in 83 patients (9.8%), of whom 17 (2.0%) had survival to hospital discharge and 15 (1.8%) had survival with good neurologic outcome. Among patients in the Utstein comparator group, survival to hospital discharge was 21.4%. Predictors of return of spontaneous circulation were age, witnessed arrest, initial shockable rhythm, time of year, time to cardiopulmonary resuscitation, and time to advanced life support. Predictors of survival to hospital discharge were age, initial shockable rhythm, time to rhythm analysis, and time to advanced life support. Predictors of survival with good neurologic outcome were age, initial shockable rhythm, and time to return of spontaneous circulation. ConclusionsThe incidence of out-of-hospital cardiac arrest with cardiopulmonary resuscitation in the Algarve was higher than in other jurisdictions while return of spontaneous circulation, survival to hospital discharge, and survival with good neurologic outcome were comparatively low. An aging population, a geographically diverse region, and a low incidence of bystander cardiopulmonary resuscitation may have contributed to these outcomes. These results confirm the importance of early cardiopulmonary resuscitation, early rhythm assessment, and early advanced life support, all of which are potentially modifiable through public education, broadening of the defibrillator network and increased availability of advanced life support teams.
- Comparação da eficácia de algumas soluções de reforço sísmico de escolas de betão armadoPublication . Tomás, Bruno; Estêvão, João M. C.A aplicação conjunta da NP EN 1998-1:2010 (EC8-1) e da NP EN 1998-3:2017 (EC8-3) na reabilitação sísmica de edifícios existentes no Algarve constitui um importante desafio técnico, designadamente em face do agravamento dos valores espectrais da ação sísmica para a generalidade dos municípios dessa região, por comparação com a anterior regulamentação. Esse desafio é ainda maior para as construções escolares, por dois motivos: por um lado, porque a ação sísmica é aumentada no contexto das análises sísmicas a realizar neste tipo de construção, nomeadamente por força da utilização de um coeficiente de importância; por outro, porque no anexo nacional do EC8-3 é exigida a verificação de segurança de três estados limites (DL, SD e NC), ao contrário dos edifícios correntes, onde somente é necessário verificar a segurança para um estado limite (SD). No contexto do projeto PERSISTAH, foi realizada a comparação da eficácia de diversas soluções de reforço de uma escola de betão armado. Foram comparados os efeitos de seis estratégias de reforço, designadamente através da adição de contraventamentos metálicos, adição de paredes resistentes, encamisamento dos pilares com betão armado e com materiais compósitos. Os resultados obtidos, com recurso a análises não lineares, demonstram que todas as soluções são viáveis, muito embora apresentem curvas de capacidade muito distintas. Na generalidade dos casos, o estado limite que mais condicionou as medidas de reforço sísmico testadas foi o NC.
- Revisiting lignin: a tour through its structural features, characterization methods and applicationsPublication . Melro, Elodie; Filipe, Alexandra; Sousa, Dora; Medronho, Bruno; Romano, AnabelaLignin is a complex organic polymer found in the plant cell wall with important biological functions, such as water transport, mechanical support, and resistance to various stresses. It is considered the second most abundant biopolymer on earth and the largest natural source of aromatics. Despite being annually co-produced in massive amounts, during cellulose fragmentation in the pulp industry and ethanol biorefinery, it is clearly undervalued; most of it is discarded or burned as fuel for energy production and, so far, only ca. 1-2% of lignin has been utilized as a high-value product. This underuse makes lignin the future resource of choice to produce green fuels and a wide range of added-value biomaterials and chemicals, which can contribute to the transition to more sustainable industries. However, its great variability between plant families combined with its complex and chemically inert structure is challenging researchers who seek for strategies regarding its valorization. With this scope, several different approaches have emerged regarding the development of better and efficient isolation methods, purification and characterization techniques, and improved methodologies for lignin chemical modification and blending with other compounds. These improvements represent important opportunities for the creation of value-added lignin-based biopolymers and materials and some have already shown potential to be scaled up. All these aspects are pedagogically introduced and discussed in this review.
- One-minute and green synthesis of magnetic iron oxide nanoparticles assisted by design of experiments and high energy ultrasound: Application to biosensing and immunoprecipitationPublication . Pérez-Beltrán, Christian Hazael; Jose Garcia-Guzman, Juan; Ferreira, Bibiana; Estevez-Hernandez, Osvaldo; Lopez-Iglesias, David; Cubillana-Aguilera, Laura; Link, Wolfgang; Stanica, N.; Rosa Da Costa, Ana; Maria Palacios-Santander, JoseThe present study is focused on the ultrafast and green synthesis, via the co-precipitation method, of magnetic nanoparticles (MNPs) based on iron oxides using design of experiments (DOE) and high energy sonochemical approach, considering two main factors: amplitude (energy) of the ultrasound probe and sonication time. The combination of these techniques allowed the development of a novel one-minute green synthesis, which drastically reduced the amount of consumed energy, solvents, reagents, time and produced residues. This green sonochemical synthesis permitted to obtain mean particle sizes of 11 ? 2 nm under the optimized conditions of amplitude = 40% (2826 J) and time = 1 min. Their composition, structure, size, morphology and magnetic properties were assessed through X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning and transmission electron microscopy (SEM & TEM), and vibrating sample magnetometry (VSM). The characterization results indicate the proper formation of MNPs, and the correct functionalization of MNPs with different coating agents. The functionalized MNPs were used as: i) biosensor, which could detect mercury in water in the range of 0.030?0.060 ppm, and ii) support onto which polyclonal antibodies were anchored and successfully bound to an osteosarcoma cell line expressing the target protein (TRIB2-GFP), as part of an immunoprecipitation assay.
- Cultivation of the red seaweed Kappaphycus alvarezii using biofloc effluentPublication . Pires, Clovis Murilo; Bazzo, Giovana Carolina; Barreto, Pedro Luiz Manique; do Espirito Santo, Carlos Manoel; Ventura, Thallis Felipe Boa; Pedra, Anna Gabrielle La Macchia; Rover, Ticiane; McGovern, Malachy; Hayashi, LeilaThe aim of this work was to evaluate the use of effluent from a Biofloc System (BFT) as a fertilizer for the red seaweed Kappaphycus alvarezii cultivated in tanks and analyze its influence on carrageenan yield and quality. Firstly, the optimum effluent concentration and period for enrichment were determined by an in vitro study. The seedlings were then cultivated for 7 days in two different culture media: 50% von Stosch solution (V) and 25% BFT (B), both diluted in sterilized seawater. Seaweeds cultivated only in sterilized seawater were used as a control (C). After this period, all plants were grown in only sterilized seawater for a further 28 days. Seedlings from V (1.05 +/- 0.02% day(-1)) and B (1.13 +/- 0.01% day(-1)) showed no significant differences in growth rates, being both higher than the control (0.91 +/- 0.06% day(-1)). Seedlings from V and B also removed a greater quantity of nitrate (58.39% and 22.97%, respectively). Seedlings from V removed 100% phosphate, while those from B removed 83.58%. The tissue nitrogen content was higher only in the V. Although no significant differences were observed among treatments in the carrageenan yield, significantly higher gel strength and viscosity were observed in B (248.85 g cm(-2) and 19.89 mPa s, respectively). According to the results, BFT effluent can be used to replace von Stosch solution to grow K. alvarezii in tanks. At the same time, the seaweed, together with bacteria and microalgae from the effluent, can be an effective biofilter in IMTA systems using bioflocs.
- Therapeutic potential of vanadium complexes with 1,10-phenanthroline ligands, quo vadis? Fate of complexes in cell media and cancer cellsPublication . Nunes, Patrique; Correia, Isabel; Cavaco, Isabel; Marques, Fernanda; Pinheiro, Teresa; Avecilla, Fernando; Pessoa, Joao Costa(VO)-O-IV-complexes formulated as [(VO)-O-IV(OSO3)(phen)(2)] (1) (phen = 1,10-phenanthroline), [(VO)-O-IV(OSO3) (Me(2)phen)(2)] (2) (Me(2)phen = 4,7-dimethyl-1,10-phenanthroline) and [(VO)-O-IV(OSO3)(amphen)(2)] (3) (amphen = 5-amino-1,10-phenanthroline) were prepared and stability in cell incubation media evaluated. Their cytotoxicity was determined against the A2780 (ovarian), MCF7 (breast) and PC3 (prostate) human cancer cells at different incubation times. While at 3 and 24 h the cytotoxicity differs for complexes and corresponding free ligands, at 72 h incubation all compounds are equally active presenting low IC50 values. Upon incubation of A2780 cells with 1-3, cellular distribution of vanadium in cytosol, membranes, nucleus and cytoskeleton, indicate that the uptake of V is low, particularly for 1, and that the uptake pattern depends on the ligand. Nuclear microscopic techniques are used for imaging and elemental quantification in whole PC3 cells incubated with 1. Once complexes are added to cell culture media, they decompose, and with time most V-IV oxidizes to V-V-species. Modeling of speciation when [(VO)-O-IV(OSO3)(phen)(2)] (1) is added to cell media is presented. At lower concentrations of 1, (VO)-O-IV- and phen-containing species are mainly bound to bovine serum albumin, while at higher concentrations [(VO)-O-IV (phen)n](2+)-complexes become relevant, being predicted that the species taken up and mechanisms of action operating depend on the total concentration of complex. This study emphasizes that for these (VO)-O-IV-systems, and probably for many others involving oxidovanadium or other labile metal complexes, it is not possible to identify active species or propose mechanisms of cytotoxic action without evaluating speciation occurring in cell media.