1,721,038 research outputs found
COX-2 inhibition induces autophagic flux and influences extracellular vesicle profile in human glioblastoma U87MG cell line
No full textIntroduction: Glioblastoma Multiforme (GBM), a lethal primary tumor of the central nervous system, is characterized by a highly infiltrating capacity, striking cellular heterogeneity, relapsing ability, and resistance to therapy. At present, the standard of therapeutic protocol consists of maximum conceivable surgical resection, followed by radiotherapy plus parallel adjuvant chemotherapy with temozolomide. Despite this, resistance to therapy limits its effectiveness, and GBM cannot be effectively controlled, being characterized by an extremely broad set of genetic and epigenetic alterations and high rates of recurrences. Several studies have suggested that gliomas, similar to most established malignant tumors, are characterized by a moderately inflammatory environment. Growing evidence over the past decades indicates the involvement of COX-2 in the progression of a variety of tumors, including GBM. We analyzed the effect of NS398, a COX-2 inhibitor, on the autophagic flux and extracellular vesicle (EV) secretion in the human U87MG glioma cell line. The effects of glioma stem cells (GSC)-derived EVs on adherent U87MG were also evaluated. Methods: After treatments, cell morphology was assessed by optical microscopy and by SEM. Cell proliferation and migration were examined using CCK-8 and scratch wound healing assay. Cell cycle profile and apoptosis were analyzed by flow cytometry. Autophagy-associated acidic vesicular organelles were quantified by acridine orange staining. A nanoparticle tracking analysis was used to assess the number and size of EVs. EV ultrastructure was verified by TEM and protein levels analyzed by WB. Acid sphingomyelinase was determined through ceramide levels. Results: NS398 was able to induce autophagy in both adherent U87MG and GSCs and EV secretion in GSCs. EVs secreted by NS398-treated GSC, but not those from untreated cells, were able to inhibit adherent U87MG cell growth and migration while also inducing a consistent level of autophagy. Conclusions: The hypothesis of COX-2 expression as GBM profile marker or interesting therapeutic target is supported by our findings. Autophagy and EV release following treatment with the COX-2 inhibitor could represent useful elements to better understand the complex biomolecular frame of GBM
Use of 1D and 2D seismic response analyses of soil deposits for seismic Microzonation of urban areas in Tuscany (Italy)
No full textThe paper firstly summarizes the main factors affecting seismic response of natural soil deposits with special attention to soil nonlinearity. Then, the available simplified approaches to assess stratigraphic and topographic amplification effects in various codes are discussed.In the second part, the paper shows the results of 1D and 2D Seismic Response Analyses (SRAs), that were performed for the urban centre of Castelnuovo di Garfagnana which is in one of the most seismic areas of Tuscany (Italy). More specifically, the construction of the geotechnical models for seismic response analyses carried out for three cross-sections is illustrated, based on geological and geotechnical information and data available in the Tuscany Region database developed in the framework of the VEL Project. The paper also describes this interactive, georeferenced database. The last part of the paper presents the results of the numerical analyses on selected representative points located along the surface of soil deposit in terms of bar plots of amplification factors. Various available criteria to express 2D amplification effects were considered and summarised. Anyway, the possible aggravation effect was computed by means of an ad - hoc defined parameter. Moreover, possible criteria to extend the SRA results that were obtained for a given geological section over the whole study area were discussed. Use of the average shear wave velocity parameter, V-s,V-30, revealed the most appropriate and cost-effective criterion
La Tribuna Illustrata, Domenica, La Disgrazia al Parco Aerostatico Presse Monte Mario
No full textIssue of the Italian newspaper "La Tribuna Illustrata" with an article about an accident during a military balloon experiment at Monte Mario in Rome on June 14, 1899 (page 204). Photographs show the deflating balloon descending into a wooded area and Oreste Vacco, the soldier killed in the accident. A color illustration on the back cover shows the soldier falling out of the balloon and two soldiers in the balloon basket.For more information about this item, visit https://archivesspace.mit.edu/repositories/2/digital_objects/79
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
Extracellular Vesicles in Prostate Cancer: New Future Clinical Strategies?
Full text linkProstate cancer (PCa) is the most common cancer--excluding skin tumors--in men older than 50 years of age. Over time, the ability to diagnose PCa has improved considerably, mainly due to the introduction of prostate-specific antigen (PSA) in the clinical routine. However, it is important to take into account that although PSA is a highly organ-specific marker, it is not cancer-specific. This shortcoming suggests the need to find new and more specific molecular markers. Several emerging PCa biomarkers have been evaluated or are being assessed for their potential use. There is increasing interest in the prospective use of extracellular vesicles as specific markers; it is well known that the content of vesicles is dependent on their cellular origin and is strongly related to the stimulus that triggers the release of the vesicles. Consequently, the identification of a disease-specific molecule (protein, lipid or RNA) associated with vesicles could facilitate their use as novel biological markers. The present review describes several in vitro studies that demonstrate the role of vesicles in PCa progression and several in vivo studies that highlight the potential use of vesicles as PCa biomarkers
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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