1,720,984 research outputs found
Synthesis and biological evaluation of pyrazolo[3,4-d]pyrimidine derivatives active as SGK1, Fyn and Src kinases inhibitors
No full textThe pathogenesis of many cancers is characterized by mutations, overexpression and dysregulation of protein kinases. As a result, increasing attention has been directed towards the identification of novel kinase inhibitors for cancer therapy.
The work performed here focuses on the synthesis of a series of pyrazolo[3,4-d]pyrimidine derivatives as inhibitors of the serine-threonine kinase SGK1, and the tyrosine kinases Fyn and Src.
The first set of compounds are analogues of the in house SGK1 inhibitor SI113 which had previously demonstrated anti-cancer activity. In fact SI113 resulted to be active on various cancer cell lines and in an in vivo hepatocellular carcinoma model. The new set of SI113 analogues are characterized by different anilines, ammines and a morpholine group in C4 and are decorated in C6 with polar chains, i.e. ethanolamine, diethanolamine, ethylene glycol and ethylenediamine. The double bond on the N1 side chain which is essential for the activity of compounds toward SGK1, was maintained.
The structures of the second set of compounds, instead, are related to the in house Fyn inhibitor SI308. From previously studies on the first generation of Fyn inhibitors, SI308 was reported as the most potent compound, demonstrating both antiproliferative activity on cancer cell lines and the ability to inhibit protein Tau phosphorylation in a cellular model of Alzheimer’s disease. The new generation of SI308 related compounds present a methyl group at the C6 position and on C3 the phenyl ring is either unsubstituted or presents a methyl group in para position.
Preliminary screening using enzyme activity assays demonstrates that some of the novel compounds are active and therefore suitable for further study using in vitro models. It is predicted that subsequent in vitro data will aid in the design of future compounds.
Furthermore, previous data on another in house compound SI306, which is active on tyrosine kinase Src, reported promising results on an in vivo xenograft model of neuroblastoma. To further study this biological activity, SI306 was re- synthesized and additional experiments were performed on in vitro models. Testing of this compound on MYCN-amplified neuroblastoma cell lines HTLA-230 and SK-N-BE-2C further confirmed the activity of SI306 and provide increased support for the inhibition of Src as a valid approach for neuroblastoma treatment.
Finally, further in vitro studies were performed on of the three previously cited in house pyrazolo[3,4-d]pyrimidines, SI306, SI308 and SI113, using patient derived glioblastoma multiforme (GBM) cell lines. This final set of work was undertaken during a visiting research fellowship period and performed in collaboration with the School of Pharmacy at the University of Nottingham (United Kingdom). Kinase inhibitor activity has been evaluated on series of patient derived GBM cell lines isolated from both the central tumor core (GCE28) and from the invasive margin of the tumor (GIN28 and GIN8). The use of such phenotypically relevant in vitro models represents an important step for GBM drug development and screening. The results gathered using these relevant cell models further demonstrate the anti-cancer activity of the pyrazolo[3,4-d]pyrimidines compounds. Moreover, investigating the compounds in combination with one another reveals that synergy can be achieved and this finding has additional implications for potentially overcoming GBM drug resistance. Additionally, to overcome the low water solubility of our pyrazolo[3,4-d]pyrimidines compounds, formulations of the lead compounds (SI306, SI308 and SI113) were prepared using miniaturized screening process based on inkjet printing technology6. The observed activity of our compounds in vitro taken together with their successful formulation highlight that our kinase inhibitors are attractive candidates for the treatment of GBM
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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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