1,721,008 research outputs found
An Update on Molecular Pathways Regulating Vasculogenic Mimicry in Human Osteosarcoma and Their Role in Canine Oncology
Full text linkCanine tumors are valuable comparative models for human counterparts, especially to explore novel biomarkers and to understand pathways and processes involved in metastasis. Vasculogenic mimicry (VM) is a unique property of malignant cancer cells which promote metastasis. Thus, it represents an opportunity to investigate both the molecular mechanisms and the therapeutic targets of a crucial phenotypic malignant switch. Although this biological process has been largely investigated in different human cancer types, including osteosarcoma, it is still largely unknown in veterinary pathology, where it has been mainly explored in canine mammary tumors. The presence of VM in human osteosarcoma is associated with poor clinical outcome, reduced patient survival, and increased risk of metastasis and it shares the main pathways involved in other type of human tumors. This review illustrates the main findings concerning the VM process in human osteosarcoma, search for the related current knowledge in canine pathology and oncology, and potential involvement of multiple pathways in VM formation, in order to provide a basis for future investigations on VM in canine tumors
Editorial: Canine osteosarcoma as a model in comparative oncology: Advances and perspective
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Fibroblastic sarcoid in a Grant's Zebra in Europe and its association with bovine papillomavirus type-1
No full textGoing 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
Histological Evaluation of Long-Term Collagen Type I Culture
No full textHistological approach to long-term culture on collagen type I permits the evaluation of vasculogenic mimicry morphological features and the identification of endothelial-like cell-specific antigens. Here, we show the preparation of collagen type I solution, the embedding and the sections cutting of D17 osteosarcoma cells long-term culture, and then the hematoxylin and eosin (H&E) staining to identify endothelial-like structure. Moreover, we provide the protocols for periodic acid-Schiff (PAS) staining to evidence glycoproteins and CD31 immunohistochemistry to exclude the presence of this endothelial marker, as per definition by vasculogenic mimicry concept. This method allows to consider long-term culture as tissue, promoting the deeper study of vascular-like structures in vitro
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
Ovarian prolapse associated with severe granulomatous hepatitis in an adult female montezuma swordtail Xiphophorus montezumae (Jordan & Snyder, 1899)
No full textIntroduction - Prolapse through the vent is relatively common in fish. Vent prolapse in fish includes intestinal prolapse through
the anal/genital pore and ovarian prolapse through the genital pore. This event can occur secondary to an infectious process or
may be consequent to straining from passing eggs or constipation, although predisposing or associated pathological conditions
are not frequently determined, especially as far as ovarian prolapse is concerned. Careful physical examination may allow to
identify the prolapsed organ, since ovarian tissue usually appears to be grainy with presence of small white to yellow follicles,
whereas intestine typically have a smooth surface (Lewbart, 1998).
Description of the case - The present case describes an adult female Montezuma swordtail, Xiphophorus montezumae (Jordan
& Snyder, 1899), showing a mass protruding from the genital pore, with macroscopical features referable to ovarian tissue. The
fish spontaneously died after a fifteen-days period of progressive reduction of food consumption, with moderate weight loss, and
it was immediately submitted to necroscopic and histopathologic exams. Post-mortem examination confirmed the ovarian prolapse,
associated with a moderate abdominal enlargement. Opening of the coelomic cavity also revealed severe hepatomegaly
associated with pale, yellow to tan liver parenchyma and presence of multiple, miliary nodules on the liver surface. Samples of
liver and ovarian tissues were fixed in 10% neutral buffered formalin, embedded in paraffin, cut in 5 μm-thick sections, stained
with haematoxylin-eosin (HE) and examined by light microscopy. Additional sections were also subjected to Ziehl-Neelsen stain,
with (P-ZN) and without (ZN) pre-treatment by a 24 h incubation in 10% periodic acid, which may improve detection of acidfast
bacilli in fish. Histologically, liver parenchyma showed multiple granulomas, characterized by a necrotic core, containing
eosinophilic cellular debris, surrounded by epithelioid cell layers of variable thickness, with presence of scattered multinucleate
giant cells. Multiple granulomatous and pre-granulomatous inflammatory foci were also detected in mesentery and ovarian
tissue. Multifocal, mild to moderate acid-fast staining was revealed by ZN, especially in the epithelioid layers, whereas P-ZN
revealed higher numbers of intensely stained acid-fast bacteria, with beaded or barred staining, which were found in dense
sheets and clumped aggregations within the necrotic core or individually in the surrounding epithelioid cells. A focal aggregation
of acid-fast bacteria was also detected in intraovarian fry tissues by P-ZN. Histological and histochemical findings were
suggestive of mycobacteriosis, although a differential diagnosis with partially acid-fast, related actinomycetes, such as Nocardia,
was considered
Conclusions - Multinucleate giant cells, characteristic of mycobacterial granulomas in mammals, have been rarely reported in
fish, since the majority of mycobacterial lesions described in fish lack these cells. Detection of acid-fast staining in intraovarian
fry tissues is also important, since vertical transmission of mycobacteria has been suggested, and transovarian passage in
livebearing fish has been reported (Roberts, 2001; Gauthier and Rhodes, 2009).
Pathological conditions associated with ovarian prolapse in fish remain frequently undefined. A unique study in an oviparous
species reported the occurrence of egg retention with a egg mass protruding from the vent in a female frogfish Antennarius striatus,
associated with an atypical, severe systemic mycobacteriosis, characterized by the absence of typical granuloma formation
(Yanong et al., 2003). To our knowledge, this is the first report of an ovarian prolapse associated with severe, multifocal granulomatous
inflammation referable to mycobacteriosis in the ovoviviparous species Xiphophorus montezumae
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
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