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Browsing by Author "Barata, Pedro"

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  • A administração na mucosa bucal como uma estratégia alternativa à via oral
    Publication . Dias, Sandra; Figueiras, Ana; Barata, Pedro; Oliveira, Rita; Santos, Delfim; Veiga, Francisco
    o principal objectivo deste trabalho foi realizar uma revisão geral sobre o mecanismo de mucoadesão, tendo em consideração aspectos tais como, as teorias explicativas de tal mecanismo, assim como os passos envolvidos no mecanismo de acção. De seguida, foi feita uma abordagem sobre polímeros bioadesivos, tendo sido expostos alguns resultados práticos no sentido de avaliar a força bioadesiva, o trabalho bioadesivo, bem como índice de swelling, de forma a obter uma matriz mucoadesiva com características optimizadas.
    2007Journal article Open access Show more
  • Antiangiogenic and antioxidant in vitro properties of hydroethanolic extract from açaí (Euterpe oleracea) dietary powder supplement
    Publication . Costa, Raquel; Azevedo, Daniela; Barata, Pedro; Soares, Raquel; Guido, Luís F.; Carvalho, Daniel O.
    The Euterpe oleracea fruit (açaí) is a promising source of polyphenols with health-promoting properties. To our knowledge, few studies have focused on the influence of açaí phytochemicals on angiogenesis, with a significant impact on cancer. This study aimed at investigating the phytochemical profile of a purple açaí hydroethanolic extract (AHE) obtained from a commercial dietary powder supplement by high-performance liquid chromatography coupled to diode array detection and electrospray ionization mass spectrometry, and evaluate its in vitro effects on distinct angiogenic steps during vessel growth and on oxidative markers in human microvascular endothelial cells (HMEC-1). The phenolic profile of AHE revealed the presence of significant levels of anthocyanins, mainly cyanidin-3-O-rutinoside, and other flavonoids with promising health effects. The in vitro studies demonstrated that AHE exerts antiangiogenic activity with no cytotoxic effect. The AHE was able to decrease HMEC-1 migration and invasion potential, as well as to inhibit the formation of capillary-like structures. Additionally, AHE increased antioxidant defenses by upregulating superoxide dismutase and catalase enzymatic activities, accompanied by a reduction in the production of reactive oxygen species. These data bring new insights into the potential application of angiogenic inhibitors present in AHE on the development of novel therapeutic approaches for angiogenesis-dependent diseases.
    2021Journal article Open access Show more
  • Capítulo 6 - Microencapsulación
    Publication . Lopes, Carla Martins; Barata, Pedro
    2012Book part Restricted access Show more
  • Chapter 5: Stimuli-responsive nanosystems for drug-targeted delivery
    Publication . Lopes, Carla Martins; Barata, Pedro; Oliveira, Rita
    2018Book part Restricted access Show more
  • Chronopharmaceutical delivery of anti-inflammatory drugs
    Publication . Barata, Pedro; Lopes, Carla Martins
    The human body follows 24 hours cycles called the circadian rhythm that affect many physiological and physiopathological processes. Chronotherapeutic diseases include asthma, cardiovascular diseases, cancer, rheumatoid arthritis and other algesia processes. Drugs behaviours in the human body are also strongly affected by circadian changes, especially in what concerns absorption and elimination. Anti-inflammatory drugs are excellent candidates to chronotherapeutical delivery. Chronotherapeutic products are able to synchronize drug delivery with circadian rhythms in order to enhance efficacy and reduce side effects. These products mainly offer pulsatile release that follow a sigmoid release profile with a combination of periods of lag time and periods of fast drug release. Many technologies, either single units or multiparticulate systems, have been suggested and some have been successfully marketed improving patients adherence and quality of life. This review aims to describe the circadian rhythms and their influences in therapeutics as well as the technologies that have been proposed to develop chronopharmaceutical dosage forms.
    2011-06-01Journal article Restricted access Show more
  • Ciclodextrinas: formação de complexos e sua aplicação farmacêutica
    Publication . Oliveira, Rita; Santos, Delfim; Barata, Pedro
    O número de moléculas com problemas de solubilidade, biodisponibilidade e permeabilidade tem vindo a aumentar. As ciclodextrinas são oligossacarídeos cíclicos com uma cavidade central hidrófoba, cuja estrutura permite formar complexos de inclusão estáveis com diversos fármacos. A complexação com ciclodextrinas permite optimizar os diversos sistemas transportadores constituídos por este tipo de fármacos, assim como solucionar problemas devidos a propriedades indesejáveis como instabilidade, más características organolépticas ou potencial irritação. The number of molecules with problems of solubility, bioavailability and permeability is increasing. Cyclodextrins are cyclic oligosaccharides with a hydrophobic central cavity, whose structure can form stable inclusion complexes with various drugs. Complexation allows the optimization of drug delivery of such drugs, and to solve problems due to undesirable properties such as instability, poor organoleptic characteristics or irritation.
    2009Journal article Open access Show more
  • Cronoterapia: estratégia futura para a libertação de fármacos
    Publication . Barata, Pedro; Lopes, Carla Martins; Santos, D.; Oliveira, Rita; Murias, I.; Veiga, F.
    O conhecimento da existência de variações fisiológicas ao longo de um período de 24 horas (variação circadiana) em vários sistemas do organismo humano tem sido explorado por parte da Indústria Farmacêutica no sentido de adaptar a administração de medicamentos de acordo com as necessidades biológicas. Deste modo, estão descritos diversos estudos que demonstram resultados eficazes da aplicação da cronoterapia no controlo de várias doenças (e.g. gastrointestinais, cardiovasculares, respiratórias, no cancro).
    2011Journal article Open access Show more
  • Current neurogenic and neuroprotective strategies to prevent and treat neurodegenerative and neuropsychiatric disorders
    Publication . Carvalho, I. M.; Barata, Pedro; Costa, P. C.; Marques, C. S.; Oliveira, Rita; Ferreira, D. C.
    The adult central nervous system is commonly known to have a very limited regenerative capacity. The presence of functional stem cells in the brain can therefore be seen as a paradox, since in other organs these are known to counterbalance cell loss derived from pathological conditions. This fact has therefore raised the possibility to stimulate neural stem cell differentiation and proliferation or survival by either stem cell replacement therapy or direct administration of neurotrophic factors or other proneurogenic molecules, which in turn has also originated regenerative medicine for the treatment of otherwise incurable neurodegenerative and neuropsychiatric disorders that take a huge toll on society. This may be facilitated by the fact that many of these disorders converge on similar pathophysiological pathways: excitotoxicity, oxidative stress, neuroinflammation, mitochondrial failure, excessive intracellular calcium and apoptosis. This review will therefore focus on the most promising achievements in promoting neuroprotection and neuroregeneration reported to date.
    2015Journal article Restricted access Show more
  • Cyclodextrin-based carriers for topical delivery of anti-inflammatory agents
    Publication . Oliveira, Rita; Barata, Pedro
    Anti-inflammatory agents topically applied are appropriate in the treatment of skin diseases, restricting the therapeutical action to the affected area and reducing systemic side effects. On the other hand, systemic activity is the aim of transdermal delivery, which can be used to minimize the first pass metabolism but also to control systemic side effects, e.g., nonsteroidal anti-inflammatory drugs. The main limitation of this route is to overcome the stratum corneum, the outermost skin barrier. In order to achieve therapeutic concentrations and to improve the drug flux, permeation enhancers are used to optimize drug permeation through the skin. Cyclodextrins and their derivatives are capable of forming inclusion complexes with poor water soluble drugs improving their water solubility, bioavailability and stability, among other features. Cyclodextrins have been used as permeation enhancers although their mechanism it not yet well known. They can also be useful in the design of new drug carriers for skin delivery, by increasing the solubility of drugs hence providing high drug content systems. Improving the drug stability and promoting drug permeation are also desirable properties that cyclodextrins can provide to novel drug carriers. Several anti-inflammatory drugs have been incorporated into various skin delivery cyclodextrin-based systems such as liposomes, solid lipid nanoparticles and microemulsions.
    2011Journal article Restricted access Show more
  • Development of a platform to align education and practice: bridging Academia and the profession in Portugal
    Publication . Alves da Costa, Filipa; Martins, Ana Paula; Veiga, Francisco; Ramalhinho, Isabel; Sousa Lobo, José Manuel; Rodrigues, Luís; Granadeiro, Luiza; Castro, Matilde; Barata, Pedro; Gomes, Perpétua; Seabra, Vítor; Caramona, Maria Margarida
    Limited fitness for practice may result from a mismatch between education and practice. Aiming to meet the common interests of academics and practitioners, the Portuguese Pharmaceutical Society (PPS) developed the Education and Practice Platform (EPP). The EPP includes one representative from each pharmacy faculty, and all Councils of Speciality Boards of Practice. Brainstorming with involved parties enabled sharing of interests, concerns and identifying a common path. Aims, mission, vision and values were set. The EPP's mission is to: act as an enabler to foster the quality and adequacy of education through sharing best practices, ultimately leading to facilitate professional integration, and to foster quality development in teaching practices with recognition for autonomy in freedom to teach and to learn. Its vision is an alignment of education and practice with the PPS' statutes to ensure validation of the competences defined for each practice area, and compliance with international guidance. Key performance indicators (KPIs) were set. Activities developed include the creation of a national forum to discuss education and practice, development of workshops on teaching methods and pharmacy internships, enhanced representation in international events and response to global and national requests. Ongoing work focuses on the creation of a common training framework in hospital and community pharmacy practice adapted to Portugal. The EPP is a worldwide case study, encouraging the development of discussion contributing to an open climate of sharing best practices, indirectly leading to foster a better alignment between education and practice. Many of these results are so far intangible in scientific terms but worth describing.
    2020Journal article Open access Show more