1,721,039 research outputs found

    Epidermal growth factor receptor and caveolin-1 coexpression identifies adult supratentorial ependymomas with rapid unfavorable outcomes

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    Supratentorial ependymomas account for a minority of intracranial ependymomas, which still have uncertain prognostic markers. Among them, epidermal growth factor receptor (EGFR) overexpression correlates with a poor prognosis. In glioblastoma cells, EGFR function has been reported to be regulated by its migration from cell membrane infoldings called caveolae and by its colo-calization with the caveolae-associated protein caveolin-1 (cav-1). Therefore, we decided to investigate cav-1 expression and coexpression with EGFR in a series of adult intracranial ependymomas. We analyzed 22 adult supratentorial ependymomas and compared tumor grades as determined by the WHO classification and patient survival rates with the expression of EGFR, cav-1, and p53 and the values of the proliferation marker Ki-67, all tested by immunohistochemistry; in addition, we investigated the mutational profile of cav-1. The results demonstrate that the tumor grade is directly correlated with EGFR, Ki-67, and cav-1 expression only, whereas (by univariate analysis) the expression of all the studied markers, as well as the tumor histological grade, significantly correlated with the patient's overall survival (OS). By multivariate analysis using the Cox proportional hazards model, among all variables considered, cav-1 was the only independent prognostic marker related to OS (relative risk = 13.92; P =.013). Among grade II epen-dymomas, only cav-1 correlated with poor OS (P =.011), distinguishing 2 distinct subgroups of tumors with different outcomes despite sharing identical grading. All the patients studied carried wild-type cav-1 sequences, demonstrating that cav-1 overexpression is not driven by activating mutations, as previously reported in other tumor types. Interestingly, after stratifying all cases into 4 distinct groups according to cav-1 and EGFR expression (cav-1+/EGFR+, cav-1+/EGFR+, cav-1+/EGFR+, and cav-1+/EGFR+), the coexpres-sion of cav-1 and EGFR identified a subset of patients with definitively poor prognoses. Further studies are needed to support this evidence on a larger scale and to clarify how cav-1 and EGFR interaction can influence tumor aggressiveness. © The Author(s) 2010

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

    Primary bladder phaeochromocytoma diagnosed by a vet

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    Bladder phaeochromocytomas are rare neuroendocrine neoplasms whose diagnosis can be missed in spite of their rather suggestive presentation. It is mandatory to collect a thorough medical history and to recognize their typical symptoms. This study reports the case of a woman, treated for hypertensive crisis, who was diagnosed with bladder phaeochromocytoma thanks to a vet noting her fainting after micturitio

    Better see to better agree: Phosphohistone H3 (PHH3) increases inter-observer agreement in mitotic count for meningioma grading and imposes new specific thresholds

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    Background: Mitotic count on hematoxylin and eosin (H&E)-stained slides is a crucial diagnostic criterion in meningioma grading. However, mitosis assessment on H&E slides can be impaired by technical factors and by pathologist's experience. Phosphohistone H3 (PHH3) serine-10 is a mitosis-specific antibody that has proven to facilitate mitotic count in various tumors. Methods: A series of 70 meningiomas (15 grade I, 40 grade II, 15 grade III) was used to validate PHH3 intra- and interobserver reproducibility and to identify PHH3-specific mitotic thresholds. Four pathologists with different experience in neuropathology counted mitoses on both H&E- and PHH3-stained slides. Results: H&E and PHH3 mitotic rates were highly correlated (Pearson's r = 0.92, P <. 0001). PHH3 mitotic counts had both a good mean interobserver correlation (Rm = 0.83) and a good intraclass correlation (0.78), higher than H&E mitotic indices (Rm = 0.77, intraclass correlation = 0.71). After further stratification of ..

    "Benign" metastatic meningioma: clinico-pathological analysis of one case metastasising to the lung and overview on the concepts of either primitive or metastatic meningiomas of the lung.

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    Lung '' metastases '' of benign meningiomas are rarely described events of biological and clinical interest. We, here, report of a 70-year-old healthy woman found by CT scan to have multiple lesions, the two largest in the right lung on routine examination. Anamnesis revealed that the patient underwent a surgical resection of cerebral meningioma 12 years before. The larger lung lesion was a 3-cm node located in the right lung and was removed by wedge resection. Macroscopically, it showed well-defined borders, whitish colour and firm consistency; histologically, it was uniformly composed by spindle meningothelial cells arranged in fascicules including psammoma bodies. The morphological and immunohistochemical features of this lesion, together with the similarity with the original cerebral tumour and its indolent evolution, led to a final diagnosis of '' benign '' meningioma metastatic to the lung. Lung metastatic meningiomas may be a diagnostic challenge because of their unusual site of presentation and the possible confusion with primitive lung meningiomas or primary mesenchymal lung lesions. They represent a typical example of '' benign '' tumours that may implant to the lung similar to other tumours, definitely considered benign but reported to rarely present unusual secondary localization

    Variations on the Author

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    “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

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    We 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

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    We 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
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