1,720,977 research outputs found
Dopamine plasma membrane transporter (DAT) in rat thymus and spleen: an immunochemical and immunohistochemical study
No full textThe expression of the dopamine plasma membrane transporter (DAT) was investigated in rat thymus and spleen by immunochemical and immunohistochemical techniques. Antibodies raised against a peptide mapping near the amino terminus of DAT were bound to a single band of approximately 76 kDa in thymus and spleen membranes as well as in striatal and kidney membranes which were used as dopaminergic reference tissues. Reverse transcription-polymerase chain reaction analysis revealed that both thymus and spleen expressed DAT mRNA. Immunohistochemistry revealed in rat thymus a DAT immune reaction in the wall of arteries located in septa of connective tissue as well as in the medulla, with a reticular localization and an apparent negative reaction of thymocytes. In the spleen, DAT immunoreactivity was located primarily in the red-white pulp marginal zone, within small cells, likely corresponding to lymphocytes and in the wall of white pulp arteries. The presence of a dopamine transporter suggests that dopamine released in the lymphoid microenvironment may contribute to neuroimmune modulation. It cannot be excluded a different activity of dopamine in primary and secondary immune organs, such as maturation and selection of lymphocytes and activation of immune responses in the spleen
Quantitative image analysis of choroid and retinal vasculature in SHR: a model of cerebrovascular hypertensive changes?
No full textRetinal and choroids arteries changes were investigated ophthalmoscopically and with morphometric techniques in spontaneously hypertensive rats (SHR) of 26 weeks either untreated (control animals) or treated for 12 weeks equi-hypotensive doses of the Ca2+ antagonist nicardipine or of the non-dihydropyridine type vasodilatator hydralazine. Retinal and choroid arteries hypertensive changes were compared with those affecting pial and intracerebral arteries of frontal lobe. Ophthalmoscopic analysis revealed in control SHR a rarefaction of capillaries and a decrease of their length and area. Treatment with nicardipine and to a lesser extent with hydralazine countered ophthalmoscopic changes noticeable in SHR. Morphometric analysis revealed thickening of the wall and luminal narrowing of retinal, choroids, pial, and intracerebral arteries. Anti-hypertensive treatment decreased thickening of the arterial wall and increased luminal narrowing of different arteries investigated. Nicardipine was more effective than hydralazine in countering arterial hypertensive changes in SHR and displayed a vasodilatory activity on small sized retinal and cerebral arteries, that represent a vascular segment not sensitive to hydralazine. Comparative evaluation of the wall-to-lumen ratio revealed a similar pattern between retinal and intracerebral arteries, but not between other arteries investigated. This suggests that analysis of retinal arteries may be predictive of brain intracerebral arteries changes in hypertension
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
Dopamine receptor subtypes in the human pulmonary arterial tree
No full textDopamine induces vasorelaxation of pulmonary artery primarily through an endothelium-dependent mechanism, but dopamine receptor subtypes involved in these mechanisms have not been identified yet. The expression and localization of dopamine D1-like (D1 and D5) and D2-like (D2, D3 and D4) receptors were investigated in hilar, lobar and intrapulmonary branches of human pulmonary artery by immunoblotting and immunohistochemistry. Pulmonary artery expresses dopamine D1, D2, D4 and D5 receptor subtypes, but not the D3 receptor subtype. Dopamine D1 and to a lesser extent D5 receptors were accumulated primarily in the endothelium of extrapulmonary branches of pulmonary artery. A faint dopamine D1 and D5 receptor immunoreactivity was found in the inner media of extrapulmonary and of large sized intrapulmonary branches of pulmonary artery, but not in medium- or small-sized intrapulmonary artery branches. Dopamine D2 and to a lesser extent D4 receptor immunoreactivity co-localized with the tyrosine hydroxylase-immunoreactive sympathetic plexus supplying pulmonary artery was found in the adventitia and in the adventitia-media of both extra- and different-sized intrapulmonary branches of pulmonary artery. These findings suggest the possible role of dopamine receptors in the pulmonary endothelium-dependent vasorelaxing activity. The D1 receptor subtype seems to be the most involved in this mechanism. Dopamine D2-like receptors are prejunctional and are located at the level of sympathetic neuroeffector plexus. The heterogeneous distribution and density of dopamine receptor subtypes along the human pulmonary arterial tree may be related to the different functional roles of dopamine at various levels of the pulmonary circulation
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
- …
