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Drug Delivery to the brain: in vivo evaluation on surface engeneered nanoparticles
No full textDrug Delivery to the brain: in vivo evaluation on surface engeneered nanoparticle
Nanotech approaches to CNS delivery: nanoparticle surface modification to obtain long-circulating polymeric drug carriers
No full textThere is a broad interest in the development of nanoparticles (NPs) carrying on their surface carbohydrates such as sialic acids. It is known that these carbohydrates influence the biological and physical properties of biopharmaceutical proteins and living cells. Macromolecular compounds containing these carbohydrates showed an anti-recognition effect, exert an antiviral effect and also are able to be recognized by the cell surface of some kind of cancer cells. Thus, in the present research we performed two different approaches in order to obtain polymeric (poly(d,l-lactide-co-glycolide), PLGA) NPs surface decorated with the sialic acid N-acetylneuraminic acid (Neu5Ac). The first strategy that has been followed is based on the derivatization of the polyester PLGA with the thioderivative of Neu5Ac, starting material for the preparation of the NPs; the second is based on the synthesis of compounds potentially able to insert their lipophilic moiety into the underivatized PLGA NPs during their preparation, and to display their hydrophilic moiety (Neu5Ac) on their surface. The first approach allowed the obtainment of NPs surface decorated with Neu5Ac, as evidenced by ESCA spectroscopy and interaction with the lectin Wheat Germ Agglutinin. Moreover, a formulation of these NPs suitable for in vitro assays showed that they are phagocytosed by human monocytes with an apparently different mechanism with respect of those made of underivatized PLGA. The second strategy led to NPs in which their surface appears to be very different with respect to the NPs obtained following the first strategy, with the carboxylic groups of Neu5Ac markedly shielded. Thus, the new Neu5Ac-modified PLGA polyester represent a useful starting material for the preparation of NPs surface decorated with this sialic acid
Sialic acid as surface modifier of polymeric PLGA nanoparticles
No full textNanoparticles for drug delivery to CN
Nanotechnology for the CNS drug delivery and targeting
No full textIn the last years, the application of "nanotechnology “to the field of “medicine” surely represented the most innovative strategy to cope with diseases and it coule be named as nanomedicine applied to difficult-to-treat diseases. As known, in this field of research, the most important goal to be reached is an increase in selectivity and specificity of drug action. Several results with stimulating findings in preclinical or clinical phases have been reached by using nanocarriers, delivering agents to targeted pathologies, and among them, it is known that neuro-pathologies represent a stimulating issue. In fact, the pharmaceutical treatment of Central Nervous System (CNS) disorders is the second largest area of therapy, following cardiovascular diseases. Nowadays, non-invasive drug delivery systems for CNS are actively studied. The nano-technological approach consist of the use of nanosystems (colloidal carriers) which could be polymer-based (nanoparticles, Np) or solid lipid material made (solid lipid nanoparticles, SLNp) and lipid-based (liposomes, LP). In fact, the development of these new delivery systems started with the discovery that properly surface-engineered colloidal vectors, with a diameter around 200 nm, were shown to be able to cross the BBB without apparent damage, and to deliver drugs or genetic materials into the brain. During this talk, an overview will be presented considering the most recent literature results of nanomedicine applied to brain diseases, carried out with all the most popular kinds of nanoparticulate systems, focusing in particular on peptide-decorated nanosystems able to target the CNS
The bridge between Nanotechnology and Neuroscience: Neuro-Nanomedicine
No full textThe application of nanotechnology to the field of medicine is now at the cutting edge of scientific research. Named as Nanomedicine, this smart strategy is aimed to find new approaches for therapeutic application in the difficult-to-treat pathologies, as neurological diseases. Applied to Central Nervous System (CNS) pathologies, nanocarriers, engineered for the specific passage across the Blood-Brain Barrier (BBB), have been widely studied with stimulating and interesting results. The in vivo and in vitro experiments clearly demonstrated the potential of this kind of approach, that, now, clearly needs a higher grade of translation of the research to preclinical model of pathologies. This paper provides for an incisive description of the rationale and the development of nanomedicine applied to neuroscience, the neuro-nanomedicine
Nanotech approaches to CNS delivery: nanoparticles surface modification to obtain long circulating polymeric drug carriers
No full textNanotech approaches to CNS delivery: nanoparticles surface modification to obtain long circulating polymeric drug carrier
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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