1,721,075 research outputs found
Validation of standard definition of sensitive versus refractory relapsed small cell lung cancer: A pooled analysis of topotecan second-line trials
No full textBackground Relapsed small cell lung cancer (SCLC) is classified into sensitive or resistant according to treatment-free interval (TFI) longer or shorter than 60 (criteria 1) or 90 (criteria 2) days. However, these criteria are based on small old studies and are inconsistent among different studies. The present study aimed at validating these criteria and assessing additional clinical parameters predictive of response rate (RR) and overall survival (OS). Patients and methods A database of six GlaxoSmithKline-sponsored trials of intravenous topotecan-based second-line chemotherapy was analysed. Validation of sensitive/resistant definition was performed on the entire dataset (631 patients), while study of additional parameters and development of prognostic model was conducted dividing the database into derivation and validation sets. Results The association between criterion 1 or 2 and RR was confirmed. Changing TFI cut-off or adding response to first-line did not improve accuracy. In addition to TFI (P = 0.007), only presence of liver metastasis (P = 0.046) was found to affect the probability of objective response. TFI, age, liver metastases, performance status (PS), albumin, haemoglobin and sodium levels were identified as independent prognostic factors for OS. A prognostic model, based on these variables, was able to separate relapsed SCLC into low versus high risk categories (median OS 41.4 versus 20.0 weeks). Conclusions This study confirms the value of standard criteria for relapsed SCLC outcome prediction. Patients with TFI < 60 days are refractory to second-line chemotherapy and have poor OS. Patients with liver metastasis and/or PS2 and/or low albumin, regardless of TFI, have similarly poor outcome.© 2014 Elsevier Ltd. All rights reserved
Prognostic role of hyponatremia in 564 small cell lung cancer patients treated with topotecan
No full textObjectives: Hyponatremia is reported in about 15% of small cell lung cancer (SCLC). Variable results of the prognostic significance of low plasmatic sodium (Napl) have been reported. Our study was performed to investigate the prognostic role of hyponatremia in SCLC patients treated in second-line with topotecan chemotherapy. Materials and methods: Data were retrospectively collected from a database including clinical data from 631 patients enrolled in 6 prospective topotecan iv studies. Final data were obtained from 564 patients in which data on baseline Napl were available. Univariate and multivariate analysis were carried out to study the possible correlation between Napl and second-line clinical outcomes. Results: Hyponatremia (Napl<135mequiv./l) was present in 101 cases (17.9%). Napl was <125mequiv./l in 16 patients (2.8%), 126-130mequiv./l in 11 (2%), 130-134mequiv./l in 74 (13.1%), while 463 patients (82.1%) showed normal values. The median survival was 28.7 weeks in patients with normal Napl, and 21.1 weeks in patients with hyponatremia (p<0.0001, HR=1.67, 95%CI=1.32-2.10). By Cox multivariate analysis, hyponatremia was associated with poorer prognosis (p=0.0024, HR=1.44, 95%CI=1.13-1.82). A not statistically significant trend of correlation between hyponatremia and progression-free survival (p=0.085, HR=1.23, 95%CI 0.97-1.55) and response rate (p=0.5037, OR=0.81, 95%CI 0.44-1.49) was observed. Conclusion: Hyponatremia is an independent prognostic factor for patients with SCLC treated with topotecan in second-line setting. Further studies are needed to prospectically confirm these results and to develop an optimal therapy for hyponatremic patients
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
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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