2,094 research outputs found

    Development of dioctadecyldimethylammonium bromide/monoolein liposomes for gene delivery

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    The artificial introduction of nucleic acids (NA) into mammalian cells (transfection) has become, in recent years, a well-established procedure in basic and applied research, which allowed the study of gene function and regulation. The advances in this area have made possible the use of these methods for gene-based medicines, which constitute alternative therapeutic approaches. One of the most prominent methods is lipofection that uses cationic liposome/NA complexes (a.k.a. lipoplexes) for the complexation, transport and release of therapeutic sequences into target cells. Although yielding lower transfection efficiencies compared with viral gene delivery, lipofection vectors are much safer for medical applications because no significant mutational or toxicological risk exist. Dioctadecyldimethylammonium Bromide (DODAB)/Monoolein (MO) liposomes have recently been described as a new promising alternative to common transfection reagents, due to the pioneering application of MO as helper lipid in lipoplex formulations. In this chapter, we will review the effect of MO on the physicochemical properties of DODAB/MO liposomes and pDNA/DODAB/MO lipoplexes. How lipoplex properties may affect the interaction with different extracellular components and their cell uptake and trafficking will be discussed. The importance of lipoplex biocompatibility towards efficient gene therapy will also be approached presenting pDNA/DODAB/MO system as a lipoplex model, supporting the use of MO as new helper lipid in lipofection.FCTCOMPETEThis work was supported by FCT research project PTDC/QUI/69795/2006, which is cofunded by the program COMPETE from QREN with co-participation from the European Community fund FEDER; CFUM [PEst-C/FIS/UI0607/2011]; CBMA [Pest C/BIA/UI4050/2011]; J.P.N. Silva holds a PhD Grant (SFRH/BD/46968/2008); A. C.N. Oliveira holds a PhD grant (SFRH/BD/68588/2010)

    Evaluation of antioxidant activity of selected Brazilian plants extracts

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    Numerous diseases are induced by free radicals and it has long been recognized that naturally occurring substances in higher plants have antioxidant activityinfo:eu-repo/semantics/publishedVersio

    DODAB:MO versus novel liposomes for protein delivery: comparing toxicity and encapsulation efficiency

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    UID/BIA/04050/2019, funded by national funds through the FCT IP, and project FUN2CYT: Harnessing the potential for biomedical applications of pleiotropic cytokines LIF and oncostatin M (PTDC/BTM-MAT/30568/2017, POCI-01-0145-FEDER-030568) supported by POCI through FEDER and FCT IPinfo:eu-repo/semantics/publishedVersio

    Transfusion reactions: diagnosis and treatment

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    Most transfusion provide safe and effective temporary replacement of blood components. As with other medical interventions, however, transfusions are associated with certain risks, and only when the expected benefits outweigh the potential risks should transfusion therapy be initiated. This chapter addresses the principal categories of transfusion reactions. For each individual type of reaction, the pathophysiology, diagnosis, treatment, and prevention are discussed. More detailed coverage is available elsewhere.A maior parte das transfusões resulta em reposição temporária, efetiva e segurade hemocomponentes. Como outras intervenções médicas, entretanto, as transfusões são associadas a certos riscos, e, somente quando os benefícios esperados sobrepõem os riscos potenciais, a transfusão deve ser iniciada. Este capítulo discorre sobre as principais categorias de reações transfusionais, discutindo a fisiopatologia, o diagnóstico, o tratamento, e a prevenção dessas reações.

    Strecker degradation of amino acids promoted by a camphor-derived sulfonamide

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    A camphor-derived sulfonimine with a conjugated carbonyl group, oxoimine 1 (O2SNC10H13O), reacts with amino acids (glycine, L-alanine, L-phenylalanine, L-leucine) to form a compound O2SNC10H13NC10H14NSO2 (2) which was characterized by spectroscopic means (MS and NMR) and supported by DFT calculations. The product, a single diastereoisomer, contains two oxoimine units connected by a –N= bridge, and thus has a structural analogy to the colored product Ruhemann´s purple obtained by the ninhydrin reaction with amino acids. A plausible reaction mechanism that involves zwitterions, a Strecker degradation of an intermediate imine and water-catalyzed tautomerizations was developed by means of DFT calculations on potential transition states

    Potential contribution of selected metallic restorative dentistry materials to X-ray fluorescence

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    Recent advances have led to the use of new materials in dental restoration which is an area of rapid growth. Applications include improving oral aesthetics and essential rehabilitation, whilst procedures range from the recovery of partial elements (inlays) to fitting dental implants. Ceramics, polymers and metallic materials have all been successfully employed in dental applications and benefit from new cost efficient manufacturing techniques. The application of radiographic techniques in dentistry and other medicine is also increasing, and the combination of new materials and radiation can lead to an elevated health risk. X-rays can interact with metallic materials producing X-ray fluorescence, which can increase the radiation dose in proximity to restorative material and increase the risk of live biological tissue becoming cancerous. The issue demands consideration so that the biological risks associated with such procedures are kept as low as possible. Comparisons of doses calculated for several materials have provided evidence that the Ti cp and NiCrTi alloys present less contribution to the increase of dose in surrounding soft tissue and the potential deleterious biological effects. On the other hand, Amalgam appears to be the most deleterious alloy

    Evaluation of drying and storage conditions on nutritional and sensory properties of dried galega kale (Brassica oleracea L. var. Acephala)

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    This work evaluated the effect of the air-drying temperature and vacuum packaging on quality and nutritional compounds of dehydrated galega kale, previously steam blanched, during 5 months of storage. When compared with the vacuum packaged kale, the packaging without vacuum yielded improved nutritional features, in general. This approach combined with a drying temperature of 40°C resulted in retention percentages of 62, 38, 92, and 48% for vitamin C, total phenolic content, total antioxidant capacity, and chlorophylls, respectively. The acceptance of the dried product by the consumer was assessed through a focus group. The participants classified the product as a practical and convenient alternative to cook healthier dishes. The appearance of dried galega kale was described as being fragile and being with nice smell, natural colour, and flavour similar to the fresh product. In conclusion, the herein presented product was addressed as an innovation with multiple possible applications in several recipes.info:eu-repo/semantics/publishedVersio
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