1,720,972 research outputs found
p27Kip1 is inactivated in human colorectal cancer by cytoplasmic localization associated with activation of Akt/PKB
No full textp27Kip1 is a nuclear member of the Kip/Cip family of cyclin-dependent kinase inhibitors and is a negative cell cycle regulator that is thought to play a role in tumour suppression. Reduced levels of p27Kip1 are frequent in human cancers and these have been associated with poor prognosis. We have analysed p27Kip1 expression and intracellular localization in 70 human colorectal cancers by western blotting and immunohistochemistry and the results related to Akt expression and clinical pathological parameters. p27Kip1 protein expression, as evaluated by western blotting, was absent or reduced in about 63% of colorectal cancers compared with both peritumoral and normal tissue. Cytoplasmic p27Kip1 was detected, by immunohistochemical analysis, in 30% (21 of 70) of cases indicating that translocation of p27Kip1 protein into the cytoplasm may be responsible for p27Kip1 inactivation. The analysis of phosphorylated Akt by western blotting indicated that it was expressed in 38% (8 of 21) of tumours showing cytoplasmic p27Kip1. Patients whose cancer presented accumulation of cytoplasmic p27Kip1 showed poorer outcomes for cancer-related relapse and survival. These results suggest that cytoplasmic p27Kip1 localization, associated or not with Akt activation, may contribute to colorectal tumorigenesis and metastasis and it may be useful as a negative prognostic factor for the outcome of patients with colorectal cancer
Port in oncology practice: 3-monthly locking with normal saline for catheter maintenance, a preliminary report
No full textIntroduction Patients with cancer need stable venous access using central vascular devices like central venous ports and peripherally inserted central catheters that can be used for a wide range of indications. Numerous flushing protocols exist including different frequencies for catheter locking to maintain catheter patency. The aim of this retrospective study was to evaluate the incidence of lumen occlusion of central venous ports in a group of adult cancer patients, adopting a policy of locking with normal saline every three months. Methods This is a single-center retrospective observational study. During follow-up, we analyzed adult cancer patients who had undergone port insertion from January 1st, 2007 to August 31st, 2014. Flushing and locking were performed every three months with a syringe containing normal saline. Results We collected data from 381 patients with ports inserted in subclavian vein (379 patients) and in the right jugular vein (2 patients). Locking was performed during 3-monthly follow-up visits. Median follow-up was 810 days (90-2700 days). Among 381 ports, 59 were removed; the reasons for removal were: end of use (45 cases), catheter rupture (9 cases), dislocation (3 cases) and catheter-related bloodstream infection (2 cases). We had no reports of lumen occlusion. Conclusions Our data suggest that locking ports with normal saline every three months is not associated with an increased risk of lumen occlusion. </jats:sec
Prognostic value of relative cerebral blood volume (rCBV) in patients with recurrent glioblastoma multiforme treated with bevacizumab
No full textBACKGROUND:
To assess whether the early monitoring of the effects of bevacizumab in patients with recurrent glioblastoma multiforme (GBM) using perfusional dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) before and after the beginning of anti-angiogenic therapy is predictive of treatment response.
METHODS:
Thirteen patients with recurrent GBM underwent perfusion MRI with relative cerebral blood volume (rCBV) mapping before (T0) and after the beginning (T1) of bevacizumab treatment. Recurrence Regions of Interest (RoIs) were positioned on the enhancing component of tumoral tissue revealed by post-contrast T1-weighted images. The rCBV measurements on the corresponding maps were made before and after the start of the anti-angiogenic therapy. The Cox proportional hazards model and the Kaplan-Meier method were used with the log-rank test to establish whether pre- and post-bevacizumab rCBV predicted progression-free survival (PFS). We tried to assess if there was a correlation between rCBV at T0 and rCBV at T1 using the Pearson's correlation coefficient.
RESULTS:
In the univariable analysis, rCBV was significantly predictive of PFS at T0 (HR= 5.3, p=0.003) and at T1 (HR=4.14, p=0.04). Similarly, in the multivariate Cox model analysis, rCBV was predictive of PFS at T0 (HR=4.4, p=0.04) and T1 (HR=4.2, p=0.02). PFS was longer in patients whose rCBV was less than 4.50 ml/100g at T0 and less than 1.83 ml/100g at T1 than in patients with higher rCBV values. There was a moderate positive correlation between rCBV at T0 and rCBV at T1 (P=0.032, R=0.546).
CONCLUSIONS:
Despite the limited number of enrolled patients, rCBV assessed using DSC-MRI through the parameter rCBV is proved reliable in predicting the effects of anti-angiogenic treatment in patients with recurrent GBM
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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