1,720,972 research outputs found

    The vitamin-E derivative U-X3836-E in the low-dose streptozocin-treated mouse: Effects on diabetes development

    No full text
    Low-dose streptozocin-treated (LDS) mice were administered an inhibitor of lipid peroxidation, U-83836-E (a derivative of vitamin E), in order to observe its ability to alter the onset of diabetes. Ten or 20 mg/kg body wt. per day of U-83836-E were given to mice for 7 days and they were killed after 21 days. Results revealed that there was a significant increase in glycaemia in treated groups up to day 14 after which no further increase was noticed. Superoxide dismutase (SOD) assay showed that: (1) the LDS treatment significantly reduces SOD activity when compared with untreated controls (P < 0.005); (2) U-83836-E increases SOD levels (when compared with untreated controls); and (3) U-83836-E counteracts LDS treatment, since SOD activity is significantly higher with respect to that found in LDS-controls (P < 0.05), and SOD levels were significantly higher with respect to that found in Group 2 animals (P < 0.05), but significantly lower with respect to those found in groups 3 and 4 (P < 0.005). Moreover, malondialdehyde (MDA), the end-product of lipoperoxidation, was found at much higher levels in LDS controls than in the other groups and the lowest values were found in U-83836-E controls and in normoglycaemic animals treated with both streptozocin and U-83836-E. Morphological observations demonstrated that islet β cells were of normal appearance in normoglycaemic animals of the treated groups. In conclusion, the in vivo inhibition of lipid peroxidation by this compound produces a limited but significant prevention of the islet β cell destruction. © 1995

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Full text link
    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

    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

    The Harderian gland in autoimmune diabetes of the nonobese diabetic mouse

    No full text
    Infiltration of the nonobese diabetic (NOD) mouse's Harderian gland (HG) was studied in 1-30-week-old animals. A mononuclear cell invasion of this gland is first seen in 8-week-old female mice (i.e., at a slightly later age than that for the onset of infiltration of pancreatic islets). Infiltrating elements are mainly located at the hilus of the gland or at one or two foci (periacinar infiltration) within the parenchyma. In the latter case, a few elements infiltrate the fibrous connective tissue surrounding the acini (one or more) without damaging them. The most severe histopathological lesion was observed in 16-week-old animals; at this time infiltration ranges from a still focal lesion to complete acinar destruction of the gland. Ultrastructural observations confirm that in several cases acinar cells are destroyed and the HG parenchyma is substituted with infiltrating elements, fibroblasts, and connective tissue. HG infiltration is comparable to the pancreatic inflammatory infiltration; the two processes are very similar, though insulitis starts slightly earlier than HG infiltration. Furthermore, as for insulitis and diabetes incidence, HG infiltration affects NOD males less than females. Moreover, immunocytochemistry has shown that T lymphocytes are the prevalent infiltrating element both in pancreatic islets and HGs. Further studies are required to understand the reasons for autoimmune destruction of this gland
    corecore