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    Detection of gonadotropin-releasing hormone receptor in normal human pituitary cells and pituitary adenomas using immunohistochemistry

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    Gonadotropin-releasing hormone (GnRH), which is a well-known regulator of gonadotroph function, has recently been considered to be a paracrine factor involved in the control of somatotroph, lactotroph, and corticotroph cells. GnRH action is initiated by binding to a specific cell surface receptor, the gonadotropin-releasing hormone receptor (GnRHR), which is expressed by follicle-stimulating hormone/luteinizing hormone (FSH/LH) cells. Using in situ hybridization techniques, GnRHR messenger ribonucleic acid (mRNA) has recently been detected in normal human anterior pituitary gland and in various pituitary adenomas, including FSH/LH-cell, growth hormone (GH)-cell, adrenocorticotropic hormone (ACTH)-cell, and null-cell adenomas. However, immunohistochemical studies indicating the specific cell distribution of GnRHR in normal pituitary cells have never been reported. The aim of the present investigation was to evaluate the immunohistochemical expression of GnRHR in different types of normal pituitary cells and related tumors. Using double-label immunohistochemical techniques on formalin-fixed and paraffin-embedded tissues and specific antibodies directed against pituitary hormones and GnRHR, we found GnRHR immunoreactivity not only in FSH/LH cells, but also in GH- and thyroid-stimulating hormone (TSH) cells. GnRHR was detected in FSH/LH-cell, GH-cell, mixed GH- and prolactin (PRL)-cell, and alpha-subunit (alpha-SU)/null-cell adenomas. The findings of this study suggest that the interaction between GnRH and GnRHR may play a role in paracrine/autocrine regulation of different types of normal pituitary cells and pituitary adenoma

    Microvessel density in prostate carcinoma

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    The objective of this work was to assess the correlation between microvessel density (MVD), pathological stage and disease recurrence in a series of patients who underwent radical prostatectomy for prostate cancer. Pathological material from 75 consecutive radical prostatectomies performed before 1994 without neo-adjuvant treatment, in which sufficient follow-up data were available, was re-examined. Paraffin embedded material was re-cut and hematoxylin and eosin (H&E) stained. Areas of maximal angiogenesis within tumor were identified. Expression of CD34 was investigated by using the monoclonal antibody MY 10. Within the areas of maximal angiogenesis, microvessels expressing CD34 were counted and specimens were divided into two groups, one showing a count of less than 90 microvessels per microscopic field at 200 × magnification (MVD 90). The MVD was then related to pathological stage, Gleason score (GS) and outcome of the disease. Mean follow-up was 84 months. Clinical or biochemical progression was observed in 38.6% of patients. In low GS cases, MVD was always 90. In high GS MVD was always >90. MVD was positively associated with a higher pathological stage. Progression of the disease was observed in 20% of MVD 90 (P=0.006). Mantel-Haensz test showed a correlation between MVD and time to progression (P <0.05). Although problems exist in methods of counting and in the cut-off number of vessels, which can discriminate the risk categories, it may be concluded that microvessel counts, using CD34 monoclonal antibody, can accurately predict the outcome of radical prostatectomy

    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

    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
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