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GHB-C rats: the control line of GHB-sensitive (GHB-S) and GHB-resistant (GHB-R) rats
No full textGamma-hydroxybutyric acid (GHB)-sensitive (GHB-S) and GHB-resistant (GHB-R) rats have been selectively bred for their opposite sensitivity to the sedative/hypnotic effect of GHB. This opposite sensitivity has been found to generalize to the GABA(B) receptor agonist, baclofen. A control line [named GHB-control (GHB-C)] has been derived from the foundation stock of GHB-S and GHB-R rats. GHB-C rats have been bred without any evaluation of their sensitivity to GHB. The experiments described here were designed to evaluate the sensitivity of GHB-C rats, from the 13th generation, to the sedative/hypnotic effect of GHB (1 g/kg, i.p.) and baclofen (20 mg/kg, i.p.). All measures (onset, sleep time and r = sleep time/onset) of sensitivity to GHB- and baclofen-induced sedation/hypnosis in GHB-C rats were significantly different from and intermediate to those recorded in GHB-S and GHB-R rats. Furthermore, these values were similar to those recorded in the foundation stock. These results suggest that GHB-C rats may constitute a valid control line for GHB-S and GHB-R rats, representing the "general population" from which GHB-S and GHB-R rats were derived. Furthermore, the relative equidistance of sensitivity to GHB- and baclofen-induced sedation/hypnosis of GHB-C rats from those of GHB-S and GHB-R rats suggests that genetic factors contributes to the development of both sensitivity in GHB-S rats and resistance in GHB-R rats
Up-regulation of GABA(B) receptors by chronic administration of the GABA(B) receptor antagonist SCH 50,911
No full textChronic treatment of mice with the specific gamma-aminobutyrie acid(B) (GABA(B)) receptor antagonist (2S)(+)-5.5-(dimethyl-2-morpholineacetic acid (SCH 50,911) increased both the number of GABA(B) receptors in the whole brain (measured as [H-1]CGP 54626 [S-(R,R)]-3-[[1-(3,4-dichlorophenyl)amino]-2-hydroxypropyl](cyclohexylmethyl)phosphinic acid hydrochloride binding) and the ability of bacloten to activate GABA(B) receptor coupled G-protein (measured as % reduction of the EC50 of baclofen to activate [S-15]GTP gamma S binding).
The results indicate that persistent blockade of GABA(B) receptors leads to their compensatory up-regulation and suggest that GABA(B) receptors are tonically activated by endogenous GABA. (c) 2005 Elsevier B.V. All rights reserved
Evaluation for the withdrawal syndrome from gamma-hydroxybutyric acid (GHB), gamma-butyrolactone (GBL), and 1,4-butanediol (1,4-BD) in different rat lines.
No full textA severe and life-threatening gamma-hydroxybutyric acid (GHB) withdrawal syndrome, clinically similar to the alcohol withdrawal syndrome, is increasingly being reported in GHB addicts. We investigated for the occurrence of withdrawal in Wistar and Sprague-Dawley rats, and in the selectively bred lines of GHB-sensitive (GHB-S) and Sardinian alcohol-preferring (sP) rats, following chronic administration of GHB, gamma-butyrolactone (GBL), and/or 1,4-butanediol (1,4-BD). Using validated rodent alcohol withdrawal scoring scales, little to no spontaneous or pharmacologically precipitated withdrawal effects were observed in Wistar, Sprague-Dawley, or GHB-S rats. Conversely, sP rats displayed both spontaneous and precipitated audiogenic seizures following abrupt cessation of chronic GHB or 1,4-BD administration and following pharmacological challenge with the GABA(B) receptor-selective antagonist, SCH 50911, respectively
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Withdrawal syndrome from gamma-hydroxybutyric acid (GHB) and 1,4-butanediol (1,4-BD) in Sardinian alcohol-preferring rats.
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