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This paper provides a review of the literature on the use of Pluronic (R) triblock copolymers for drug encapsulation over the last 10 years. A special focus is given to the progress of drug delivery systems (e.g., micelles, liposomes, micro/nanoemulsions, hydrogels and nanogels, and polymersomes and niosomes); the beneficial aspects of Pluronic (R) triblock copolymers as biological response modifiers and as pharmaceutical additives, adjuvants, and stabilizers, are also discussed. The advantages and limitations encountered in developing site-specific targeting approaches based on Pluronic-based nanostructures in cancer treatment are highlighted, in addition to inno-vative examples for improving tumor cytotoxicity while reducing side effects. info:eu-repo/semantics/publishedVersion

In the last decade, research studies have increased on the development of delivery systems for polyphenols, for protection, improvement of stability and increase of their bioavailability. Rosmarinic acid is a polyphenol with described bioactivities, such as antioxidant, anti-mutagenic, anti-bacterial and anti-viral capabilities. Thus, the aim of this research work was to produce stable solid lipid nanoparticles (SLN) using carnauba wax as lipidic matrix, for delivery of rosmarinic acid, to be further incorporated into food matrices. Hence, different concentrations of wax (0.5, 1 and 1.5%, w/v) and percentages of surfactant (1, 2 and 3%, v/v) were tested. Physical properties, surface morphology and association efficiencies were studied at time of production and after 28 day at refrigerated storage. Thermal properties and the nature of the chemical interactions between the lipids waxes and rosmarinic acid were also evaluated. The particles showed range size between 35-927 nm and zeta potentials of ca. -38 to 40, showing high stability, with no risk of aggregation due to electric repulsion of SLN. High association efficiencies % (ca. 99%) were obtained. FTIR analyses proved the association of rosmarinic acid and lipidic matrix. The low lipid and high surfactant concentrations leads to small SLN. The surfactant, polysorbate 80 decreases the interfacial tension in the SLN surfaces, preventing aggregation, leading to the development of small particles. These properties were maintained throughout the 28 day of refrigerated storage, and no rosmarinic acid was released by the particles during refrigeration, indicating good compatibility between rosmarinic acid and the waxy core of SLN. The optimum range values to obtain the desirable features for incorporation in a functional food suggest formulations containing 1.0 and 1.5% (w/v) of lipid and 2% (v/v) of surfactant. This journal is © The Royal Society of Chemistry 2015.

Cancer is a major cause of morbidity and mortality worldwide. Chemotherapeutic agents currently used in cancer treatment are associated with severe side effects and development of resistance. Thus, there is a pressing need for novel and more potent anticancer drugs with high selectivity for tumor cells and reduced toxicity to normal tissue. Natural products remain an important source of bioactive compounds and drug prototypes that can lead to new and more effective antitumor agents. Coniferous plants are rich in abietane diterpenoids with a wide range of biological activities that provide useful templates for synthetic modification. Abietic acid and dehydroabietic acid (DHA), the major diterpenic resin acids from Pinus rosin, and dehydroabietylamine found in commercial disproportionated rosin amine, display antibacterial and antitumor properties. These compounds and their synthetic derivatives have been reported as promising anticancer agents with potent growth inhibitory activity against several types of human cancer cell lines, including breast, ovarian, prostate, colon, liver, lung and cervical carcinoma cells. Their mechanisms of action are diverse and include DNA binding, induction of apoptosis or oncosis, tubulin polymerization inhibition and disruption of intracellular cholesterol transport. This review covers the main aspects of natural rosin abietane diterpenoids (abietic acid, DHA and DHAA) and synthetic derivatives concerning their anti-proliferative, cytotoxic and antitumor activities, mechanisms of action and structure- activity relationships relevant for the development of novel anticancer agents for cancer chemotherapy.

A presença de filtros UV nos produtos de cuidado da pele e cosméticos representa um dos benefícios principais prestados aos consumidores a nível de saúde pública. Os perigos da exposição diária aos raios ultravioleta são, atualmente, bem conhecidos e descritos. Os raios UV têm influência em várias alterações cutâneas no fotoenvelhecimento. Os danos da radiação UV na pele verificam-se diretamente a nível do DNA e indiretamente no sistema imunitário a nível cutâneo. As formulações cosméticas têm uma vasta gama de ingredientes fotoprotetores ativos para incorporação consoante os diferentes tipos de fotoprotetor desejado. A seleção dos mesmos é feita consoante a legislação e regulamentação do país de produção e qual será o produto final no mercado. Nesta dissertação foi estudado o efeito da cafeína como fotoestabilizador de protetores solares bioativos contendo avobenzona e p-metoxicinamato de otilo (instáveis quando presentes na mesma formulação). Alguns dos efeitos benéfícos da cafeína na saúde humana têm sido comprovados ao longo dos tempos. Os seus mecanismos de ação demonstram que incorporada em determinadas formulações e concentrações poderá funcionar como um filtro solar potente e trazer novidades ao mundo da proteção solar., The presence of UV filters in skin care products and cosmetics represents one of the major benefits to consumers in public health. The risks associated to daily exposure to Ultraviolet (UV) rays are currently part of established knowledge. UV rays have influence on almost all skin changes related to photoaging. Skin damages provoked by UV radiation in the skin occur both directly at the DNA level and indirectly in the cutaneous immune system. The cosmetic formulations have a wide range of photoprotective active ingredients that can be incorporated depending on the different types of photoprotector desired. Their selection is done according to the legislation and regulations in the country of production and what will be the final product in the market. In this dissertation the effect of caffeine as a photo-stabilizer of bioactive sunscreens containing avobenzone and p-methoxycinnamate (unstable when present in the same formulation) was studied. Some of the beneficial effects of caffeine on human health have been proven over time. its mechanisms of action demonstrate that, as part of certain formulations and concentrations, caffeine can act as a potente sunscreen and bring innovation to the world of sun protection., Orientação: Pedro Lopes da Fonte