1,721,010 research outputs found
ESPRESSIONE DI MARKERS IMMUNOISTOCHIMICI IN GONADI NORMALI E PATOLOGICHE DI CANE
Full text linkThis study aimed to determine the immunophenotypical characterization of canine Sertoli cells (SCs) and related tumors and canine ovarian neoplasms.
In veterinary literature histological and immunohistochemical aspects of canine Sertoli cell tumor (SCT) are poorly investigated and data on normal testes of mature and immature dogs are absent.
In human medicine, numerous studies have shown that during maturation from fetal to adult testis, SCs undergo a process of differentiation whereby the expression of some markers is maintained, while other markers disappear and others are acquired.
The comparison between the expression of cellular markers in normal and neoplastic testes may make clearer the temporal sequence of markers appearance in the dog, important for understanding the mechanisms underlying their re-expression in disorders of the adult testis. The analogies observed between canine and human species might clarify if the dog could be considered a good animal model for human testicular cancer.
To evaluate the expression of Sertoli cell markers in normal and neoplastic canine testes, formalin fixed and paraffin embedded sections of testes from 2 fetuses, 15 newborns (from 0 to 20 days old), 5 puppies (from 43 days to 6 months old), 14 adult dogs and 21 canine SCTs (20 benign and 1 metastatic malignant SCT) were processed for histology and immunohistochemistry (ABC method) with antibodies against vimentin (1:1000), CKAE1/AE3 (1:3000), desmin (1:300), INH α (1:40) and AMH (1:30000).
Histologically, 13/20 benign SCTs were classified as classical SCTs while 7/20, showing intracytoplasmic vacuoles, were considered “lipid rich”. The malignant SCT, largely necrotic, was composed of large cystic tubules lined by numerous layers of poorly-differentiated neoplastic SCs characterized by marked anisocytosis and anisokaryosis.
The mitotic index of the SCTs ranged from 0 to1.6, with the highest value recorded in the malignant SCT.
Immunohistologically, vimentin was always expressed by normal SCs from puppies and adults and by all SCTs taken in consideration. On the other hand, only 1 foetus and 4 newborns were positive immunolabelled.
INH α was present exclusively in fetal and neonatal testes and in 13/21 SCTs, while desmin and CKAE1/AE3 were never present within normal testes but exclusively expressed by 7/21 and 5/21 SCTs, respectively. Finally, AMH was always expressed by foetal and neonatal testes, by the youngest puppies (43-45 days old) and by all the SCTs taken in consideration.
We speculate that the expression of CKAE1/AE3, INH α, desmin and AMH observed in SCTs and not in mature testes may be a manifestation of de-differentiation. In fact, neoplastic SCs re-express foetal and neonatal makers, normally lost with maturation, demonstrating an immature phenotype. The re-expression of immunophenotypical markers of immaturity has been already described in several testicular pathologic conditions and the identification of the mechanisms via which this “cellular reversal maturation” occurs should be further investigated.
Regarding ovarian canine epithelial tumours, given the variety of histological features that characterize this lesion and that can cause diagnostic difficulties or misinterpretation, the aim of this study was to investigate the reliability of the marker HBME-1 in canine normal ovaries, granulosa cell tumors, and epithelial ovarian neoplasms to determine whether this marker could be included in an immunohistochemical panel for differential diagnoses of canine ovarian tumors.
Samples were obtained from 4 normal ovaries, 10 granulosa cell tumors, and 18 epithelial ovarian tumors. After formalin fixation and paraffin embedding, tissue sections were stained with hematoxylin and eosin and probed immunohistochemically for the HBME-1 marker. Granulosa cells and related tumors were consistently negative for HBME-1. Normal ovarian surface epithelium and 17 out of 18 ovarian epithelial tumors were positive for HBME-1. The results suggested that HBME-1 would be a useful marker for the differential diagnosis of ovarian tumors in the dog
Rabbit Sertoli cells: Immunohistochemical profile from neonatal to adult age
No full textImmunohistochemistry (IHC) on formalin-fixed paraffin-embedded tissue specimens is a widely used laboratory technique that allows the demonstration and the direct microscopical observation of antigens within tissue sections by means of specific antibodies. IHC is one the best tools to define the immunophenotype of a cell during maturation or neoplastic transformation.To investigate the immunophenotype of postnatal rabbit Sertoli cell, from neonatal to adult age, in this chapter, the immunohistochemical protocol described is one of the most common: the avidin-biotin complex (ABC) method
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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