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Overexpression of the G1 domain of PG-M/Versican induces overgrowth of human leiomyosarcoma cells by altering their proliferation-apoptosis equilibrium
No full textTumour dormancy induced by overexpression of PG-M/versican G1 domain in soft tissue sarcomas
No full textDominant role of the G1 domain of PG-M/Versican in the control of the proliferation-apoptosis balance and invasive capabilities of tumour cells.
No full textABSTRACT
To dissect the role of the globular domains of PGM/versican a large hyaluronan binding
proteoglycan (PG) enriched in tumor lesions we have stably transduced a human
leiomyosarcoma cell line with either the G1 or G3 domain of the PG and subsequently assayed
the effect of this manipulation on several cellular processes in vitro and in vivo. G1- and G3-
overexpressing cells were found to exhibit an enhanced growth that was more accentuated in the
absence of serum components and was seen both when cells were cultured on ECM substrates
and in the absence of ECM anchorage. Accordingly, if inoculated subcutaneously into nude
mice, G1 transfectants formed larger tumor masses than control cells at the site of implantation,
albeit after a certain latency period. Upon binding to cell surface CD44, proliferation of G1-, but
not G3-, overexpressing cells were dose dependently inhibited by exogenous hyaluronan (HA) or
HA fragments. G1- and G3-transduced cells did not differ in their intrinsic ability to adhere and
migrate on various purified ECM components, whereas G1-overproducing sarcoma cells were
more invasive than the corresponding G3 mutants, and their locomotion was perturbed by
exogenous HA. The augmented anchorage-independent growth exhibited solely by G1-
transduced was largely ascribable to a reduced apoptotic rate, thereby indicating a shift in the
proliferation−apoptosis equilibrium of the cells toward the former. In fact, G1-overexpressing
cells appeared resistant to both cytotoxic drug-induced and Fas-dependent programmed cell
death, and this resistance implicated mitochondrial apoptotic genes. The results indicate that the
terminal domains of versican may differentially control propagation of tumor cells and diversely
modulate their responses to environmental HA
Key words: soft tissue sarcoma hyaluronan G1 G
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
A new epitope presenting system displays a HIV-1 V3 loop sequence and induces neutralizing antibodies.
No full textThe principal neutralizing domain, IGPGRAF sequence, from the V3-loop of HIV-I was inserted in two positions on the surface of the protein that makes up the capside shell of the insect flock House Virus. The hybrid proteins were expressed in insect cells via recombinant baculoviruses. Three different hybrids were used as immunogens: two with a single copy of the insert in different positions of the carrier protein and a third with two copies of the insert at the same positions as before. All hybrid proteins induced strong and broad specific immune response in guinea pigs against different V3-loop sequences, However, only one of the hybrid proteins was able to induce a strong neutralizing response against MN and IIIB HIV-1 isolates. Our results demonstrate that a very short peptide sequence of HIV-I can constitute a valuable immunogen able to induce a neutralizing response if presented to the immune system in the context of the FHV capsomer structure
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
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