1,720,954 research outputs found
Tailoring copolymer architectures and macromolecular interactions for enhanced nanotherapeutic delivery: A design-by-architecture approach
No full textAmphiphilic copolymers with precise macromolecular topologies are crucial in nanomedicine for enhancing drug delivery by improving solubilization, stabilization, and therapeutic efficacy on target tissues. This study employs a design-by-architecture approach to identify factors influencing interactions between synthesized macromolecules and biological systems for optimal drug nanodelivery. Copolymers combining poly(epsilon-caprolactone) blocks and poly(polyethylene glycol methacrylate) or poly(glycerol methacrylate), were synthesized to investigate how architectural adjustments impact self-assembly, nanoparticle size, drug loading, and biomolecule interactions. Linear and brush block copolymers with varied block lengths were studied for their self-assembly behavior in aqueous environments. Both copolymer types formed smaller nanoparticles with extended hydrophilic blocks, with brush block copolymers showing superior performance due to their peculiar macromolecular architecture. Incorporating 'clickable' glycidyl units within the hydrophilic block minimally affected particle size. Controlled functionalization with thiol groups resulted in stable nanoparticles with enhanced size reduction and mucoadhesive properties, potentially improving targeted drug delivery and therapeutic effects
Complex macromolecular architectures for tailored interactions and targeted therapy
No full textLAUREA MAGISTRALEI nanocarrier polimerici (NC) hanno acquisito un ruolo rilevante nel campo della somministrazione di farmaci. Negli ultimi anni, le attività di ricerca hanno dimostrato che è possibile progettare e sintetizzare sistemi di rilascio di farmaci con proprietà fisico-chimiche controllate attraverso un approccio di progettazione razionale dei polimeri. La regolazione della composizione e dell'architettura dei copolimeri a blocchi di interesse è essenziale per garantire l'efficienza di carico, la cinetica di rilascio e la biodistribuzione del farmaco desiderate. Questo progetto mira a ottenere una libreria di copolimeri a blocchi anfifilici composti da poly(ε-caprolactone) (PCL), poly(ethylene glycol) methacrylate (PEGMA) e polyglycidyl methacrylate (PgMA), trattati con differenti agenti funzionalizzanti (tioli e peptidi) per ottenere NCs che presentino proprietà diverse a seconda dell'applicazione prevista. La sintesi dei copolimeri ha combinato due tecniche: la polimerizzazione ad apertura ad anello (ROP) per il blocco idrofobico e la polimerizzazione radicale a trasferimento atomico (ATRP) per il blocco idrofilo. Tutti i copolimeri contenenti gMA sono stati funzionalizzati mediante una modifica post-polimerizzazione (“click reaction”) sfruttando il suo anello epossidico altamente sensibile. I NCs polimerici sono stati ottenuti per nanoprecipitazione in ambiente acquoso. Attraverso la funzionalizzazione con gruppi tiolici, sono state prodotte nanoparticelle con capacità mucoadesive e di riduzione delle dimensioni, in grado di migliorare la somministrazione e i risultati terapeutici. Inoltre, è stata dimostrata la possibilità di generare sistemi ibridi che combinano NPs polimeriche con NPs d'oro, con l'obiettivo finale di sfruttare un effetto curativo sinergico. Parallelamente, è stata perfezionata la reazione di funzionalizzazione con il peptide RGD, che facilita l'adesione cellulare delle NPs al tumore bersaglio legando i recettori di integrina sovraespressi nel cancro alla prostata curabile con un farmaco epigenetico, e utilizzata in questo lavoro per valutare la capacità di incapsulamento delle NCs.Polymer nanocarriers (NCs) have acquired a relevant role in the field of drug delivery. In recent years, research activities have shown that it is possible to design and synthesize drug delivery systems with controlled physicochemical properties through the rational polymer design approach. Adjusting the composition and architecture of the block copolymers of interest is essential to ensure the desired loading efficiency, release kinetics, and drug biodistribution. This project aims at obtaining a library of amphiphilic block copolymers composed of poly(ε-caprolactone) (PCL), poly(ethylene glycol) methacrylate (PEGMA), and polyglycidyl methacrylate (PgMA), variedly treated with functionalizing agents (thiols and peptides) to obtain NCs presenting different properties according to the intended application. The copolymer synthesis combined two techniques: ring-opening polymerization (ROP) for the hydrophobic block and atom transfer radical polymerization (ATRP) for the hydrophilic block of the amphiphiles. All copolymers containing gMA were functionalized by click post-polymerization modification exploiting its highly sensitive epoxy ring. Polymeric nanocarriers were obtained by nanoprecipitation in aqueous media. Through functionalization with thiol groups, nanoparticles with mucoadhesive and size-reduction capabilities were produced able to improve delivery and therapeutic outcomes. In addition, the possibility to generate hybrid systems combining polymeric NPs with gold NPs was proved with the ultimate goal of exploiting a synergistic curative effect. In parallel, the functionalization reaction with RGD peptide, which facilitates NPs cellular adhesion on target tumor by binding integrin receptors overexpressed in prostate cancer curable by an epigenetic drug , was refined and used in this work to evaluate the encapsulation ability of NCs
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
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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