1,720,954 research outputs found
Molecular and metabolic determinants of metastasis development and progression
Get PDFMACC1, ein Hauptregulator von Metastasen, ist an zahlreichen Kennzeichen von Krebs beteiligt, einschließlich dereguliertem Metabolismus. Dennoch ist seine Rolle im Krebsstoffwechsel unklar. In der vorliegenden Arbeit wurde eine systematische Analyse von MACC1-getriebenen metabolischen Netzwerken durchgeführt. MACC1 erhöhte die GLUT1 auf Zellmembrane, was zu einer erhöhten Glukoseanreicherung, einem erhöhten Glukosefluss und somit zu einer erhöhten Zellproliferation führte. Außerdem, reduzierte MACC1 den Glutaminfluss unabhängig von der Nährstoffverfügbarkeit. Bei Glucoseentzug erhöhte MACC1 die Pyruvataufnahme und zeigte aber die geringe Auswirkungen auf den Pyruvatfluss. In vivo, MACC1 zeigte erhöhte Aufnahme von 18F-FDG und 18F-Glutamat in Lebermetastasen. Zusammengefasst zeigen diese Ergebnisse, dass MACC1 mehrere Wirkungen auf den Krebs-Metabolismus zeigt, was es attraktiv macht, seine Wirkungen in Krebsmodellen weiter zu untersuchen.
Metastasierung ist die Haupttodesursache bei Darmkrebs. Fünfzehn bis zwanzig Prozent der Darmkrebs Patienten im Stadium II entwickeln im Verlauf der Erkrankung Metastasen, jedoch bleiben die Kriterien der Wahrscheinlichkeit mit welcher Patienten von Chemotherapie profitieren werden ungenau. Hier wurde das Potenzial der Plasma-Metabolomik zur Vorhersage von Metachronmetastasen untersucht. Plasma metabolische Profile wurden wesentlich unterschiedlich zwischen nicht-metastasierten und metachron metastasierten Patienten gefunden. Wie Klassifikationsmodelle aus Entscheidungsbäumen und Support-Vektor-Maschinen gezeigt haben die Plasmametaboliten haben die Fähigkeit nicht-metastasierte von metachron metastasierten Darmkrebs Patienten zu unterscheiden, mit einer durschnittlichen Vorhersagegenauigkeit von 0,75 bzw. 0,82 für jede der Methoden, angemessen. Zusammen, zeigen diese Ergebnisse, dass Plasmametaboliten das Potenzial haben, Darmkrebs Patienten gemäß ihrem Metastasierungsrisiko nichtinvasiv zu stratifizieren.MACC1, a master regulator of metastasis, is involved in most hallmarks of cancer, including deregulated metabolism. Yet, fragmentary data on its role in cancer metabolism exist. Here, a systematic analysis of MACC1-driven metabolic networks by elucidation of cell nutrient preferences, environment dependent alterations of nutrient utilization, metabolic pathway functionality and metabolic tracing using 13C-labeled metabolic substrates had been performed. MACC1 was found to enhance surface GLUT1 thus leading to increased glucose depletion, glucose flux and hence increased cell proliferation. Besides, MACC1 was found to reduce glutamine flux independent of nutrient availability. Upon glucose deprivation MACC1 was found to enhance pyruvate uptake exhibiting minor effects on pyruvate flux. In vivo, MACC1 increased uptakes of 18F-FDG and 18F-glutamate in liver metastatic lesions. Together, these findings demonstrate that MACC1 exhibits multiple effects on cancer metabolism, thus making it attractive to further study its effects in cancer models.
Metastasis is the main cause of death from colorectal cancer (CRC). Fifteen to twenty percent of stage II CRC patients develop metastasis during the course of disease, however the criteria of likely benefitting patients from chemotherapy remain imprecise. Here, the potential of plasma metabolomics to predict metachronous metastasis was assessed. Plasma metabolic profiles were shown to be significantly different between non-metastasized and metachronously metastasized CRC patients. As demonstrated by supervised classifications using decision trees and support vector machines plasma metabolites have the power to distinguish non-metastasized from metachronously metastasized CRC patients giving average prediction accuracy of 0.75 and 0.82 for each of the methods, respectively. Together, these results demonstrate that plasma metabolites have the potential to non-invasively stratify CRC patients according to their metastasis risk
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
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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