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Author Correction: Cytosolic actin isoforms form networks with different rheological properties that indicate specific biological function
No full textDissecting the roles of the Dectin-1R in the bladder innate defences
Full text linkPh. D. ThesisPrevious work using immortalised cells transfected with a NF-κB reporter and challenged with
zymosan, to mimic a fungal infection, suggested possible co-operation between Dectin-1 and
TLR5 receptors in urogenital tissues. These data were interesting as research describing
Dectin-1R functioning relates specifically to myeloid derived cells and TLR5, classically, is
known to function as a homodimer. The aim of the research reported in this thesis was
therefore to focus on the Dectin-1 and TLR5 receptors in the bladder urothelium, with the
objective of investigating Dectin-1 receptor functioning, Dectin1/TLR5 receptor co-operation
and cell signalling events following a zymosan (β-glucan) challenge.
Western analyses of cell lysates from a bladder biopsy and immortalised RT4 bladder cells
using a Dectin-1R antibody (R&D systems, AF1859) revealed the synthesis of proteins
representing full-length and truncated (stalk-less) Dectin-1 receptors. These data supported
the use of the immortalised RT4 cells in all subsequent analyses exploring Dectin-1R
functioning in the urothelial tissues. Following challenge of the cells with the yeast cell wall
extract zymosan (50ug/ml) increased synthesis of an array of host defence agents including
hBD2, IL-8 and LCN2 were observed (p<0.05). Furthermore IL-8 effector synthesis was
significantly reduced following CLEC7A (Dectin-1R) gene knockdown (p<0.05) and antibody
blocking of the Dectin-1R (p<0.01). These data supported synthesis of the Dectin-1R in
urothelial cells and a role in defending the bladder against a fungal challenge.
Knocking-down the TLR5 gene in RT4 cells (80% knockdown) and challenging the cells with
zymosan, resulted in a significant reduction in hBD2, IL8 and LCN2 synthesis (p<0.05). These
data suggested co-operation between the Dectin-1 and TLR5 receptors in bladder cells, which
was supported by immunostaining and a proximity ligation assay approach. In addition these
analyses supported clustering of the Dectin-1 and TLR5 receptors following activation.
Experiments to explore roles for the encoded Dectin-1 receptor isoforms, 1, 2 and 4, in the
TLR5 co-operation events involved engineering a suite of stable cell lines each over-expressing
a Dectin-1 receptor isoform and either a TLR5 full-length or TLR5 truncated receptor. This
approach exploited the pVitro2-neo-mcs vector, which is able to co-express two cDNA
sequences simultaneously. However, the resultant cell lines did not over-express the Dectin-1
and TLR5 receptors. It was hypothesised that the increased number of receptors synthesised
by the cells over-loaded the urothelial cell membranes causing gene silencing and/or cell death.
The signalling mechanisms activating the transcription of host effector genes following a
zymosan challenge of RT4 bladder cells were explored using western analyses and an antibody
to Syk-P (Cell Signalling, C87C1), SYK gene knockdown and piceatannol (100 ug/ml) a Syk
inhibitor followed by ELISA to measure LCN2 and IL-8 media concentrations. No
phosphorylation of Syk was observed and the knock-down/inhibition approaches had no
significant effects on the media concentrations of either IL-8 or LCN2. However, knockdown of
the RAF1 gene resulted in decreased secretion of the host defence molecules LCN2 and IL-8
(p<0.01). Additionally western blot analyses showed phosphorylation and degradation of the
NF-κB inhibitor IκBα. These data suggested that Dectin-1R activation in response to zymosan in
bladder cells involved Raf-1 signalling, which supported a non-canonical signalling pathway.
In summary, Dectin-1 receptors were shown to be synthesized in RT4 bladder epithelial cells
and were activated in response to zymosan (fungal) challenge resulting in the production of
host defence effector molecules. Data showed potential co-operation between Dectin-1 and
TLR5 receptors in mediating the bladder cell response. Dectin-1R signalling in urothelial cells
was also orchestrated via a non-canonical signalling pathway involving Raf-1. These data
support a novel host defence mechanism, involving Dectin-1 and TLR5 receptors functioning
co-operatively, to defend urothelial from fungal infections.Dr William Edmund Harker Foundatio
Cytosolic actin isoforms form networks with different rheological properties that indicate specific biological function
No full textAbstract The implications of the existence of different actins expressed in epithelial cells for network mechanics and dynamics is investigated by microrheology and confocal imaging. γ-actin predominately found in the apical cortex forms stiffer networks compared to β-actin, which is preferentially organized in stress fibers. We attribute this to selective interactions with Mg2+-ions interconnecting the filaments’ N-termini. Bundling propensity of the isoforms is different in the presence of Mg2+-ions, while crosslinkers such as α-actinin, fascin, and heavy meromyosin alter the mechanical response independent of the isoform. In the presence of myosin, β-actin networks show a large number of small contraction foci, while γ-actin displays larger but fewer foci indicative of a stronger interaction with myosin motors. We infer that subtle changes in the amino acid sequence of actin isoforms lead to alterations of the mechanical properties on the network level with potential implications for specific biological functions
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
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