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The Development of Intrabody Trap Technology (ITT) for Functional Genomics
Full text link1.1 - The Aim of the Research.
Antibodies can be ectopically expressed as secreted proteins in cells that do not normally express them to interfere with extracellular antigens and/or as intracellular proteins targeted to different intracellular compartments to
inhibit intracellular gene products: this has lead to an effective protein knock-out technology.
Expression of antibodies inside cells has been used successfully to ablate protein function.
The performance of antibodies that are intracellularly expressed is however somewhat unpredictable because the reducing environment of the cell cytoplasm in which they are forced to work prevents some antibodies, but
not others, to fold properly. For this reason, a selection procedure for the isolation of antibodies able to
fold correctly and to bind antigens under condition of intracellular expression would be highly desirable. The development of this novel selection procedure could exploit methods to monitor intracellular protein –
protein interactions, for instance the yeast two-hybrid technology. Such a system would greatly facilitate the isolation of candidate antibodies for intracellular antibody down-stream applications in the system of interest, and would lend itself to the development of cell-based high-throughput screening procedures in functional genomics applications.
In view of this, the creation of a new technology that allows the isolation of intracellular scFv fragments, based on their ability to bind antigen under conditions of intracellular expression has become an important goal both
for functional genomics and for gene therapy, to fulfill the requirement of antibodies with improved thermodynamic stability and solubility properties.
1.2 - Results
The following chapters will describe all the steps taken in order to achieve the final goal: the development of the intrabody trap technology (ITT), an in vivo selection and assay procedure for functional intracellular antibodies
using a two-hybrid approach. In the first part of the project we find that several characterized antibodies can bind their target antigen in eukaryotic cells when expressed in the two-hybrid format and we have been able to isolate intracellular binders from panels of scFv, all of which can bind antigen in vitro. Furthermore, we showed a model selection in which a single chain scFv was isolated from a mixture of half a million clones, indicating that this is a robust procedure that should facilitate isolation of intrabody specificity from complex mixtures.
The results form the basis of the “intrabody trap technology”, whereby many different, specific and functional antibodies can be isolated in vivo under condition of intracellular expression.
The second part of the thesis reports the demonstration that ITT can be effectively applied to the de novo
selection of functional intrabodies, by performing a real selection from polyclonal scFv fragments partially
enriched from a large naive phage library by antigen panning. The experimental procedure described in this thesis has allowed the selection of intrabodies against a protein antigen involved in Alzheimer’s disease (AD),
the microtubule associated protein tau, the main components of the paired helical filaments (PHFs), found in neurofibrillary lesions in AD brains. In particular the aim of the work was to isolate scFv fragments against a tau
fragment, which displays apoptotic capacity in different cellular context
COMPOSIZIONI IN GRADO DI PREVENIRE EVENTI NEURODEGENERATIVI E METODO PER SAGGIARNE L'ATTIVITA'
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
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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