1,720,979 research outputs found
Adjuvant chemotherapy in colorectal cancer patients with microsatellite instability - Response
No full textInresponse: The major criticism raised by Watanabe in his
letter about our recently published article (1) concerns the
number of patients with stage II and III MSI-Hcolorectal
cancer (CRC) who received chemotherapy, that ‘‘should be
around 20 at most’’ and thus ‘‘seems too small to draw any
conclusions.’’
The assumption of Watanabe on the small number of
patients in our study is based on his interpretation that among
those 65 MSI-Hwho received chemotherapy, 31 were in stage
IV. This assumption is not correct. In fact, we considered as
patients receiving adjuvant chemotherapy only those who
underwent surgical intervention with curative intent (i.e.,
radical surgery), thus excluding most of stage IV patients who
received only palliative chemotherapy. We apologize for the
fact that this explanation was not present in the text leading to
the misinterpretation of the data. On this basis, among the 65
MSI-Hpatients considered as treated with adjuvant chemotherapy,
only 2 were in stage IV whereas 25 were in stage II and
the remaining 38 were in stage III, which is almost double of
what was hypothesized.
Furthermore, Watanabe states that the results of our study
‘‘could potentially bias the significance of MSI-Has predictor of
survival in adjuvant-treated colon cancer patients’’ as shown by
the results of his study (2), which compared the survival of
MSI-Hand MSS patients in stage II and III who received
chemotherapy.
We think that our results are not completely comparable
with those of Watanabe, mainly for the reason that our study
had a different design. In his work, Watanabe compared,
among patients who received chemotherapy, those affected by
MSI-HCRC versus those with stable tumors and found a
survival advantage in the first group; this study design could
not clearly establish whether this prognostic advantage is
conferred by the better sensitivity of MSI-HCRC to chemotherapeutic
agents or is due to the presence of instability by
itself.
On the contrary, our study was designed to investigate the
sensitivity of MSI-HCRC to chemotherapy. For this reason, we
compared among MSI-HCRC patients the outcome of those
who underwent 5-fluorouracil-based chemotherapy versus
those who were not treated. The results showed that chemotherapy
did not confer any survival advantage in MSI-HCRC
patients, confirming the report of another study with larger
sample size (3). In addition, the results of multivariate analysis
in stage II and III CRC cases showed the presence of MSI-H as an independent prognostic factor: this means that even in our
study, in accordance with Watanabe’s study, among patients
who received chemotherapy, MSI-Hpatients have a better
outcome than MSS patients.
Finally, another difference between the two studies involved
the definition of MSI. To define MSI, in our study, we used the
reference marker panel, as established in Bethesda guidelines.
Watanabe used eight dinucleotide and two polyadenine
markers in most cases, or two mononucleotide markers in
those cases without normal DNA available. This could have
important implications leading to heterogeneity in the population
defined as MSI in the two investigations
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
In response. Adjuvant chemotherapy in colorectal cancer patients with microsatellite instability.
No full textTo the Editor: In a recent issue of Clinical Cancer Research (1), we read Benatti et al.'s article with interest, therein they showed significantly better survival in microsatellite instability high (MSI-H) patients than microsatellite stable patients, and concluded that the type of genomic instability could influence the prognosis of colorectal cancer, in particular, in stages II and III. Furthermore, in relation to adjuvant treatment, they concluded that fluorouracil-based chemotherapy does not seem to improve survival among MSI-H patients. Although Benatti et al. introduced our results, our research on the similar topic came to a different conclusion (2). There are major issues to be discussed as to how Benatti et al. drew their conclusions. The first point is the total number of MSI-H patients who received chemotherapy. In Benatti et al.'s study, only 65 MSI-H patients received fluorouracil-based chemotherapy; among these 65 patients, 31 patients had stage IV disease. Considering that most of the patients who had stage IV disease would have received postoperative chemotherapy, the total number of MSI-H patients, in stages II and III, who received chemotherapy seems to be much fewer than 65. The second point is how they examined the survival rate. Benatti et al. examined the survival in stage II and stage III patients separately. Therefore, the number of MSI-H patients who received chemotherapy in either stage II or III should be 20 at most. This number of patients seems to be too small to find any difference in survival. In fact, MSI-H patients who underwent chemotherapy showed higher survival rates than those who did not, although it did not reach statistical significance. Furthermore, according to the survival curve of stage II cancers, there seems to be no cancer-related death in MSI-H patients who had undergone chemotherapy. Considering all these points, the small number of MSI-H patients who underwent chemotherapy seems to be the main reason why they could not find significant differences in survival between MSI-H patients who did or did not undergo chemotherapy. All of these points are also true in an analysis of MSI-H patients in stage III. In Benatti et al.'s study, the number of MSI-H patients with chemotherapy in stage II or III seems to be too small to draw any conclusion. In our previous study, we examined 73 MSI-H patients who received chemotherapy and showed a significant difference in survival between MSI-H patients and microsatellite stable patients (2). Taken together, Benatti et al.'s study may potentially bias the significance of MSI-H as a predictor of survival in patients with adjuvant-treated colon cancer
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
