1,720,989 research outputs found
The study of cell motility and plasticity in cancer: the role of the crosstalk between BM-MSCs and tumor in osteosarcoma progression and Claisened Hexafluoro as potential inhibitor of amoeboid motility in metastatic melanoma
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Growing evidence suggest that bone marrow-derived mesenchymal stem cells (BM-MSCs) are key players in tumor stroma. Here, we investigated the cross-talk between BM-MSCs and osteosarcoma (OS) cells in tumor progression.
We revealed a strong tropism of BM-MSCs towards these tumor cells and identified monocyte chemoattractant protein (MCP)-1, growth-regulated oncogene (GRO)-α and transforming growth factor (TGF)-β1 as pivotal factors for BM-MSC chemotaxis. Once in contact with OS cells, BM-MSCs trans-differentiate into cancer-associated fibroblasts, further increasing MCP-1, GRO-α, interleukin (IL)-6 and IL-8 levels in the tumor microenvironment. These cytokines promote mesenchymal to amoeboid transition (MAT), driven by activation of the small GTPase RhoA, in OS cells, as illustrated by the in vitro assay and live imaging.
The outcome is a significant increase of aggressiveness in OS cells in terms of motility, invasiveness and trans-endothelial migration. In keeping with their enhanced trans-endothelial migration abilities, OS cells stimulated by BM-MSCs also sustain migration and invasion. Thus, BM-MSC recruitment to the OS site and the consequent cytokine-induced MAT are crucial events in OS malignancy.
Part 2
Metastatic melanoma is one of the most aggressive and lethal malignancies with a poor prognosis. Melanoma cells are able to migrate using different types of cell motility such as the rounded/amoeboid-type motility and the elongated/mesenchymal-type motility thanks to their high plasticity. Really several data underline the crucial role of amoeboid motility in the dissemination process of highly metastatic melanoma cells. Thus, targeting this process could be a promising strategy to prevent the metastatic spreading of melanoma cells.
Claisened Hexafluoro is a chemical analog of Honokiol (HKL), a biphenolic compound derived from Magnolia officinalis which has antitumoral and antimetastatic effect in numerous cancers, including melanoma.
Starting from these evidence, here we tested Claisened Hexafluoro on human metastatic melanoma cells, as an inhibitor of amoeboid motility. Data here reported demonstrate that Claisened Hexafluoro, impairing mitochondrial activity and affecting AMP-activated protein kinase (AMPK) signaling, strongly inhibits amoeboid motility and many steps of the disseminating process in vitro as well as in vivo, confirming its possible future application to fight metastatic spreading of melanoma cells
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
A comparative numerical study of the coanda effect
No full textThe tendency of a fluid or a gas jet to stay attached to a convex surface, named as Coandg effect, after the Romanian scientist Henri Marie Coandg who is considered the first to have investigated it, has many practical applications. The approaching jet adheres along the whole as long as the surface is not too sharply curved. The adherence is due to the developing, along the liquid interface, of pressures lower than the external pressure. In this paper pressure distributions caused by a 2D water jet on convex surfaces is numerically investigated. Steady flow characteristics are deduced by means of three different solvers: a pure Lagrangian, based on the Weakly Compressible Smoothed Particle hydrodynamics (WCSPH) technique, COMSOL Multiphysics and Flow-3D. For sake of clarity, elliptic shaped solid contours are taken into account. Results, consisting of pressure profiles and dynamic thrust, are investigated in terms of the ratio R1/R2 being R1 and R2 the major and minor radius respectively
CFD ANALYSIS OF WIND EFFECT ON WAVE OVERTOPPING
No full textIt is widely assumed that onshore winds significantly increase runup and overtopping; several recent research results have indeed shown that this effect cannot be neglected. The effects of the wind and of the spray generation on the overflow phenomenon thus seem to be important in the design of seawalls, even though they are difficult to quantify through hydraulic model experiments due to the problem of wind scaling.
The use of a numerical model overcomes the limits of scale effects in experimental tests, thus making it possible to consider the action of wind-induced shear stress on the increase of the up-rushing jet near the wall.
The present work presents a numerical wind stress model that takes into account such action on wave overtopping
A CFD study on impact wave loadings exerted behind overtopping type WECs
No full textOne of the most interesting characteristics of the Wave Energy Converters (WEC) based on the overtopping principle is their capability of being integrated into conventional harbor structures. However, in these cases Particular attention must be drawn to the structural stability and the nature of loadings exerted on the device. This paper presents CFD experiments on a composite breakwater including an upright section and a sloping crown simulating a WEC. The hydrodynamic forces caused by the overtopping process onto the inner face of the structure are analyzed, with a Particular focus on the impulsive events
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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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