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Pharmacological investigation on alpha-asarone in experimental model of nicotine withdrawal induced depression in mice / Ranjith Kumar Chellian
Get PDFDepression is one of the major withdrawal symptoms during smoking cessation. The
cAMP response element protein binding (CREB) and brain-derived neurotrophic factor
(BDNF) signalling pathways have been implicated in the neuroplasticity during nicotinewithdrawal in mice. Traditionally, Acorus calamus Linn (Acoraceae) rhizomes were used
to discontinue the habit of smoking cigarettes. Alpha-asarone is one of the bioactive
phytochemicals present in the rhizomes of Acorus calamus Linn and possesses an
antidepressant-like activity in ICR mice. In addition, α-asarone was shown to interact
with CREB and BDNF pathways. Hence, it is hypothesized that α-asarone could be
effective in alleviating depression-like behaviour during nicotine-withdrawal in mice.
In this study, the dose-dependent effect of α-asarone in the tail suspension test and
locomotor activity in ICR mice was studied. In addition, the possible monoaminergic
mechanism(s) involved in the antidepressant effect of α-asarone was studied in alphamethyl-para-tyrosine (AMPT, a catecholamine synthesis inhibitor) and 4-chloro-DLphenylalanine (PCPA, a serotonin synthesis inhibitor) pre-treated ICR mice, respectively,
using tail suspension test. In a separate study, the effect of α-asarone or bupropion on
nicotine-induced hypomotility and hypothermia in ICR mice was investigated. In the
nicotine-withdrawal study, the effect of repeated α-asarone or bupropion treatment in
naïve and nicotine-withdrawn C57BL6 mice was studied in forced swim test and
spontaneous locomotor activity test. In addition, the effects of repeated α-asarone or
bupropion treatment on the hippocampal CREB, phosphorylated-CREB (pCREB), and
BDNF levels in nicotine-withdrawn C57BL6 mice were measured.
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The study results showed that the acute treatment of α-asarone at lower doses (15
and 20 mg/kg, i.p.) significantly decreased the duration of immobility time in the tail
suspension test. Moreover, AMPT and PCPA pre-treatment significantly reversed the
anti-immobility effect of α-asarone (20 mg/kg, i.p.) in the tail suspension test. The effect
of α-asarone on nicotine’s pharmacological effect revealed that the α-asarone (5, 10, 20
and 30 mg/kg, i.p.) did not reverse or block the nicotine-induced hypomotility and
hypothermia in mice. However, bupropion (20 mg/kg, i.p.) significantly reversed the
nicotine-induced hypomotility and hypothermia in mice. In the nicotine-withdrawal
study, the immobility time of nicotine-withdrawn mice was significantly attenuated with
repeated α-asarone (5, 10 and 20 mg/kg, i.p. × 8 days) or bupropion (10 mg/kg, i.p. × 8
days) pretreatment in the forced swim test. However, repeated α-asarone and bupropion
treatment did not significantly alter the immobility time in the forced swim test or
spontaneous locomotor activity in naïve mice. In addition, repeated α-asarone or
bupropion pre-treatment significantly attenuated the hippocampal pCREB levels in
nicotine-withdrawn mice.
Taken together, these results suggest that α-asarone possess an antidepressant-like
activity only at lower doses through its interaction with noradrenergic, dopaminergic and
serotonergic systems in ICR mice. Furthermore, unlike bupropion, α-asarone was not
capable of interacting with nicotinic acetylcholine receptors. Besides, α-asarone treatment
attenuated the nicotine-withdrawal induced depression-like behaviour through the
modulation of hippocampal pCREB levels in nicotine-withdrawn C57BL6 mice.
Therefore, α-asarone may have a place in the treatment of depression upon cessation of
nicotine-containing products mainly in the form of cigarettes
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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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