1,723,932 research outputs found
TESI DI DOTTORATO: New biomolecular prognostic and predictive factors of response to treatments in colo-rectal cancer. CANDIDATO: G. Della Vittoria Scarpati. RELATORE: S.Pepe
No full textMicroRNAs are small RNAs that regulate gene expression at the post-transcriptional level. miRNAs exert an important role in the regulation of biological processes, and abnormal expression of miRNAs are associated with different cancers. Considering the strong association between genetic alterations and neoplastic diseases, it is not surprising that there is a special focus on the correlation between miRNAs and cancer. Several experimental studies on colorectal cancer, the most common cancer site and furthermore the second most common cause of death due to cancer, have highlighted the critical role of miRNA in regulation of wellknown oncogenic and tumour suppressor signalling pathways.
Furthermore, several investigations have described the ability of microRNA expression patterns to predict prognosis in colon cancer and support diagnosis of poorly differentiated tumours. Currently, two different approaches are applied to investigate the association between miRNA and colorectal cancer (CRC). On the one hand, miRNAs seem to regulate many known oncogenic and tumour suppressor pathways involved in the pathogenesis of CRC. This is of particular interest in colorectal neoplasms as many proteins involved in key signalling pathways in this tumour, like p53, RAS and epithelial–mesenchymal transition (EMT) transcription factors as well as members of the PI-3-K and the Wnt/β-catenin pathway seem to be affected by miRNA regulation. Their dissection in functional studies is critical for a better understanding of cancer biology, eventually aiming for the identification of novel pharmaceutical targets. On the other hand, expression profiles of hundreds of different miRNAs have been shown to bear a much higher potential as biomarkers than their mRNA counterparts. This allows a prediction of prognosis and a distinction of certain disease entities including colorectal cancer sub-types. In order to investigate miRNA differential expression in human colorectal cancer, we analyzed by microarray and real-time PCR the expression of 939 mature miRNAs in total RNA extracted from 39 rectal fresh frozen biopsies, with the aim to found a “signature” that correlates with the response to treatments. Total RNA was extracted from biopsies of patients affected by a locally advanced rectal cancer, treated with neo-adjuant chemo-radiotherapy, follwing by surgery. RNA concentration was tested by Nanodrop ND 1000 spectrophotometer and by Agilent Bioanalyzer Assay to measure the total RNA integrity (RIN) and concentration. Also small RNA was tested by Small RNA Kit to characterize the fraction of miRNAs. The expression level of mature miRNAs found their biopsy specimen, obtained prior to the combination therapy, were quantified using microarray analysis. The miRNA expression pattern was classified based on the final pathological response to the combination therapy.
We found that the expression level of 14 miRNAs were significantly different in patients with TRG 1 if compared with patients with other TRG, with a sensitivity of 78% and a specificity of 80%. The miRNA expression pattern is associated with therapeutic outcome and may be a specific “signature”. This information could be utilized as a novel biomarker to predict drug response.
La candidata ha analizzato l'espressione di una serie di microRNA in campioni di tessuto derivati da neoplasie del retto localmente avanzate, trattate con radio-chemioterapia concomitante a scopo adiuvante. Un cluster di 14 microRNA erano sovraespressi nei pazienti che ottenevano una risposta completa patologica (Tumor Regression Grade 1) dopo il trattamento neoadiuvante (sensibilità 78%; specificità 80%
La composizione di “Camma” nel carteggio tra Adelaide Ristori, Giuseppe Montanelli e Lauretta Cipriani Parra
Get PDFAmong Adelaide Ristori’s great successes, Camma, premiered in Paris on April 23rd, 1857, was written for her by Giuseppe Montanelli. From the perspective of a dramaturgical investigation into how a Grande Attrice chose and construct her repertoire, the correspondence between Montanelli and Ristori is an important case study: the author sends the various acts of the tragedy, as they were completed, to the actress, who gradually comments on their value and offers suggestions for their better stage success, well aware of the strategies to best enhance her own abilities and the expectations of the audience. Ristori’s answers, always lucid, focused and decisive, allow us to recognize to what extent a Grande Attrice would intervene on a text, tailor-made for her, considering her strengths and abilities. Thus, this essay is about the compositional strategies of the textual score and is based on an in-depth reading of the correspondence, investigated especially with regard to the actress’s interventions, whose actual realisation and success are then compared with the final script and the review of the tragedy’s outcome with audiences and critics
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
Depositional geometry and fabric types of carbonate buildups in continental rift settings
No full textDispelling 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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