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Entwicklung einer DNA-Transfer Technik für das synthetische Peptid Tat-RGD in humane Lungenzellen und deren Anwendung fur funktionelle und regulatorische Untersuchungen von RELMB
Full text linkThe presented study is organized in two sections. In the first part a DNA-transfection procedure for human lung cells employing a peptide conjugate has been established and the corresponding transfection process characterized. In the second part this new transfection strategy has been applied for studying functional aspects of the human RELMBbeta gene.
Cell-lines and primary cells exhibit a varying degree of resistance to DNA
transfection strategies. In this study, we employed the synthetic peptide TatRGD (TR), composed of the HIV-1 derived translocation peptide Tat fused to the integrin binding RGD motif, as a tool for improving DNA transfer into human pulmonary cells. Binding experiments between DNA and TR and cytotoxicity measurements of TR treated cells were undertaken to optimize DNA and TR concentrations for transfection. Addition of a complex of TR and DNA (TRD) to A549 cells yielded in significant transgene expression. When combining TRD with Lipofectamine (TRDL), the expression was increased by 5-fold over Lipofectamine (DL) and by ~30-fold over TRD mediated transfections. Also, in primary smooth muscle cells (SMC) and fibroblasts (FB) derived from pulmonary arteries, an increase in TRDL mediated transfection efficiency was observed by a factor of ~ 2 and ~ 3 over that of DL. Laser scanning confocal microscopy for visualizing TR dependent DNA uptake demonstrated that the internalization of TRDL complexes is linked to caveoli in the plasma membrane. Interfering caveoli formation by methyl-b-cyclo-dextrin drastically decreased the transfection efficiency by TR. In conclusion, the TatRGD peptide mediates efficient gene delivery in human pulmonary cells, in particular when combined with standard cationic lipid based transfection reagent. The enhancement of DNA uptake by TatRGD is suggested to be mediated by caveoli dependent endocytosis.
RELMBbeta(resistin-like molecule) represents the most related human homologue of mouse RELMBbeta also known as hypoxic-induced-mitogenic-factor (HIMF) for which no human orthologue gene exist. In this part of the study, we isolated RELMBbeta cDNA from human lung tissue and performed regulatory and functional expression studies with the TatRGD procedure. RELMBbeta mRNA was upregulated in hypoxia in human lung A549 cell line as well as primary cultured adventitial fibroblasts (FB) and smooth muscle cells (SMC) of pulmonary artery. Upon transfection of a RELMBbeta encoding expression plasmid into these cells, we observed significant induction of proliferation particularly in SMC and A549 cells. The results suggest that human RELMBbeta may contribute to hypoxic induced pulmonary vascular remodeling processes or hypoxia related fibrotic lung disease.Die vorgelegte Studie ist in zwei Abschnitte gegliedert. Im ersten Teil wird eine DNATransfektions Prozedur mit Hilfe eines Peptid-Konjugats etabliert und der zugehörige Transfektions Prozess charakterisiert. Im zweiten Teil wird diese Transfektions Strategie angewendet, um funktionelle Aspekte des humanen RELMBbeta Gens zu untersuchen. Zelllinien und primäre Zellen zeigen eine unterschiedliche Resistenz gegenüber DNATransfektions Methoden. In dieser Studie wurde das synthetische Peptid TatRGD (TR), das aus dem von HIV-1 abgeleitetem Translokations Peptid Tat und dem Integrin bindenden RGD Motiv zusammengesetzt ist, genutzt, um den DNA Transfer in humane pulmonale Zellen zu begünstigen. Bindungsexperimente zwischen DNA und TR, sowie Zytotoxizitäts Messungen von TR behandelten Zellen wurden durchgeführt, um die zu verwendenden DNA und TR Konzentrationen zu optimieren. Zugabe eines Komplexes von TR und DNA (TRD) zu A549 Zellen resultierte in signifikanter transgener Expression. Die Kombination von TRD und Lipofectamin (TRDL) verstärkte die Expression 5-fach gegebenüber Lipofectamin (DL) und 30-fach gegenüber TRD vermittelter Transfektion. Ebenso in primär kultivierten glatten Muskelzellen (SMC) und adventitialen Fibroblasten (FB), die aus Pulmonalarterien gewonnen wurden, wurde eine Steigerung der Transfektionseffizienz um den Faktor 2 bzw. 3 gegenüber DL beobachtet.Laser-Scan basierte konfokale Mikroskopie zeigte, dass die TR abhängige DNA Aufnahme abhängig von Caveolae in der Plasmamembran ist. Inhibition der Caveolae Bildung durch Methyl-b-Cyclo-Dextrin verminderte drastisch die Transfektions Effizienz durch TR. Zusammengefasst, vermittelt TatRGD einen effizienten DNA Transfer in humane pulmonale Zellen, insbesondere wenn es mit Transfektions Reagenzien, die auf kationischen Lipiden basieren, kombiniert wird. Die Steigerung der DNA Aufnahme wird vermutlich durch Caveolae-abhängige Endozytose vermittelt.
RELMBbeta(resistin-like molecule) repräsentiert das am nächsten homologe Gen von RELMBbeta der Maus, das auch unter dem Namen HIMF (hypoxic-induced-mitogenicfactor) bekannt ist, für das aber kein orthologes humanes Gen existiert. In diesem Teil der Studie isolierten wir RELMBbeta cDNA von humanem Lungen Gewebe und führten funktionelle Expressions Studien mittels der TatRGD Methode sowie Untersuchungen zu seiner Regulation durch. Wir beobachteten eine Hochregulation von RELMBbeta mRNA in Hypoxie in der epithelialen humanen Lungenzellinie A549 sowie in primär kultivierten FB und SMC der Pulmonalarterie. Nach Transfektion der Zellen mit einem Expressions plasmid kodierend für RELMBbeta beobachteten wir eine signifikante Induktion der Proliferation insbesondere in SMC und A549 Zellen. Die Ergebnisse weisen darauf hin, dass humanes RELMBbeta am pulmonal-arteriellen Remodeling Prozess in Hypoxie oder an Hypoxie-assozierten fibrotischen Lungenerkrankungen beteiligt sein könnte
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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