1,720,957 research outputs found
Involvement of HIF-1α activation in the doxorubicin resistance of human osteosarcoma cells.
No full textOsteosarcoma is the most common primary bone cancer in children and adolescents. Despite aggressive treatment regimens, survival outcomes remain unsatisfactory, particularly in patients with metastatic and/or recurrent disease. Unfortunately, treatment failure is commonly due to the development of chemoresistance, for which the underlying molecular mechanisms remain unclear. The aim of the present study was to investigate the role of hypoxia-inducible factor 1α (HIF‐1α) and its signalling pathways as mediators of drug-resistance in human osteosarcoma. Toward this aim, we established two osteosarcoma cell lines selected for resistance to doxorubicin, a drug of choice in the treatment of this tumour. Our results showed that the multidrug resistance (MDR) phenotype was also mediated by HIF-1α, the most important regulator of cell adaptation to hypoxia. Our data showed that this transcription factor promoted the outward transport of intracellular doxorubicin by activating the P-glycoprotein (P-gp) expression in osteosarcoma cells maintained in normoxic conditions. In addition, it hindered doxorubicin-induced apoptosis by regulating the expression of c-Myc and p21. Finally, we observed that the doxorubicin-resistant cells maintained for 2 months of continuous culture in a drug-free medium, lost their drug-resistance and this effect was associated with the absence of HIF-1α expression. The emerging role of HIF-1α in osteosarcoma biology indicates its use as a valuable therapeutic target
Development of a methodology to select suitable cutting techniques for the decommissioning of nuclear power plants considering site-specific requirements
No full textIn the nuclear industry field, the decommissioning of Nuclear Power Plants (NPPs) is becoming a very relevant issue due to the number of reactors that are expected to shut down in the next few decades. Each plant presents unique characteristics, not allowing to develop a standard dismantling program that can be valid for all NPPs. Several cutting techniques have been applied in the past to dismantle reactors and their internals, however the selection of a suitable cutting technology implies considering several different parameters, such us applicability, cost and secondary waste, which can make the choice challenging. In this paper, the most relevant cutting technologies (CTs) used in decommissioning projects of Nuclear Power Plants (NPPs) are presented and their advantages and drawbacks are discussed. As the customary trade-off matrix approach to compare technologies considering their main characteristics does not consider plant-specific details, a novel methodology that considers these aspects has been developed, whose aim is to combine the information on both the cutting techniques and the site-specific requirements. The proposed methodology can be used to assist stakeholders in the development of a comprehensive decommissioning plan, considering unique site characteristics
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
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
Efficacy of facial exercises in facial expression categorization in schizophrenia
No full textEmbodied cognition theories suggest that observation of facial expression induces the same pattern of muscle activation, and that this contributes to emotion recognition. Consequently, the inability to form facial expressions would affect emotional understanding. Patients with schizophrenia show a reduced ability to express and perceive facial emotions. We assumed that a physical training specifically developed to mobilize facial muscles could improve the ability to perform facial movements, and, consequently, spontaneous mimicry and facial expression recognition. Twenty-four inpatient participants with schizophrenia were randomly assigned to the experimental and control group. At the beginning and at the end of the study, both groups were submitted to a facial expression categorization test and their data compared. The experimental group underwent a training period during which the lip muscles, and the muscles around the eyes were mobilized through the execution of transitive actions. Participants were trained three times a week for five weeks. Results showed a positive impact of the physical training in the recognition of others’ facial emotions, specifically for the responses of “fear”, the emotion for which the recognition deficit in the test is most severe. This evidence suggests that a specific deficit of the sensorimotor system may result in a specific cognitive deficit
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
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
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