1,720,985 research outputs found
Synthesis of Biomimetic Light-Driven E/Z Molecular Switches
No full textOur work is devoted to the synthesis of new biomimetic molecular switches, capable to
convert light-energy into a E/Z isomerization process. Computational studies performed on
Rhodopsin have defined the penta-2,4-dieniminium cation as the minimal chromophore
whose excited-state mimics the one of the natural pigment responsible of the vision
mechanism. By embedding this π system into conformational rigid molecules we developed
a new class of molecular switches featuring a selective and ultra-fast light-driven E/Z
photoisomerization.
An intriguing process, we named “cyclopropyl ring-opening/nitrilium ion ring-closing
tandem reaction”, has been conveniently used to approach “one-pot” the pivotal
chromophore. The successful functionalization of these molecules potentially allows their
grafting to a peptide domain
Development and in vitro characterization of nanoparticles for inner ear drug delivery
Full text linkAn innovative drug delivery system for inner ear therapy is based on the use of nanoparticles (NPs): they can be considered good carriers for therapeutic drugs within the inner ear, because they increase drug diffusion and are detected in all parts of the cochlea when applied near the round window. In this study liquid crystalline NPs based on glycerol monooleate were developed and conjugated with two hydrophobic drugs, coenzyme Q10 and dexamethasone, already used for inner ear therapies but limited in their efficacy by low solubility and bioavailability. These conjugated NPs were tested in vitro on two different cell lines, as models of the inner ear cell populations: thePC12 cells, neural-like cells used as a model of neuronal differentiation, and OC-k3, derived from the organ of Corti of transgenic mice as a model of inner ear sensory cells. The NPs conjugated with coenzyme Q10 or dexamethasone were tested against cisplatin (cis-diamminedichloroplatinum(II)), a cytotoxic agent widely used for treatment of solid tumors. Although effective as antitumor agent, cisplatin induces serious collateral effects, among which ototoxicity on the auditory nerve, the stria vascularis and hair cells. The results showed that NPs conjugated with drugs are well tolerated by both cells lines and are uptaken by cells in the first few hours after treatment, delivering the conjugated compounds inside the cells. Moreover, NPs conjugated with dexamethasone were able to counteract damages caused by cisplatin, preventing apoptosis in OC-k3 cells, and increased the concentration of drug uptaken by the cells compared to the free drug treatment. Based on these results, NPs have an interesting potential as inner ear drug delivery systems
Cellule staminali mesenchimali per la prevenzione dell’ototossicità indotta dal cisplatino
No full text
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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