1,720,959 research outputs found
GENETIC BASIS OF ALCOHOL DEPENDENCE: TRIALLELIC POLYMORPHISM OF THE SEROTONIN TRANSPORTER GENE IN A POPULATION OF ALCOHOL DEPENDENT SUBJECTS FROM ITALY
No full textBackground: The involvement of genetic variants in the
neurobiology of addiction and in the pathways of reward circuits
is well established. Serotonin transporter (5-HTT) regulate
serotonergic neurotransmission and has been associated also
with alcohol dependence (AD). Aim of this study is to assess a
possible link between a tri-allelic polymorphism of the 5’-UTR
region of 5-HTT gene (SLC6A4) and AD. This tri-allelic
polymorphism is made up of the long (L) allele of 5-HTTLPR
polymorphism together with the A (La) or G (Lg) allele of the
rs25531 single nucleotide polymorphism (SNP) and the short
allele (S). Lg and S are the low-functioning alleles.
Methods: Genotyping was performed by PCR amplification of
the 5-HTTLPR region; this produces long (L) or short (S)
amplicons depending on the variable number of repeated
elements, that results, in most cases, in a 43 base pair
insertion/deletion. The rs25531 genotype was obtained by an
L specific PCR amplification followed by a mini sequencing
reaction. We investigated 439 Italian alcoholic outpatients
(male 350, female 89) at Alcohol Unit of Umberto I Hospital -
Sapienza University of Rome and 423 healthy controls (male
285, female 138).
Results: From allelic point of view, no statistically significant
difference could be evidenced between alcoholics and controls,
considering either overall population or males separated from
females. However, AD women showed higher frequency of
both the L (56.2%) and La (51.7%) allele than control women
(respectively 50.4% and 47.5%), although not statistically
significant probably because of the smallness of the sample
analysed. An higher frequency of the L allele statistically
significant (P <0.05), can be only observed in women with an
early first contact with alcohol (≤16 yo, 63.5%) compared to
control (50.4%).
Conclusions. According to our results, the 5HTTLPR and
rs25531 polymorphisms of the serotonin transporter gene
(SLC6A4) seems not to be generally involved in AD. However,
considering males and females together can lead to
underestimate important differences in allelic distribution. In
fact, at least some categories of female patients show an higher
percentage of “fully working” alleles (L and La). Genotypic
analysis and studies of larger populations are mandatory
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
Genetica della dipendenza da alcol: studio dei polimorfismi 5HTTLPR e RS25531 del gene codificante per il trasportatore della serotonina (5-HTT)
No full textPremessa: Nonostante il nutrito numero di pubblicazioni che lo vedono coinvolto, il ruolo del trasportatore della serotonina
(5-HTT), codificato dal gene SLC6A4, nella dipendenza da alcol (OMIM Entry - # 103780) non è ancora del tutto chiaro.
Scopo dello studio: Abbiamo valutato, in questo studio, il ruolo di due polimorfismi del gene SLC6A4 nella dipendenza da
alcol in una popolazione italiana: il polimorfismo di tipo VNTR 5-HTTLPR ed il polimorfismo a singolo nucleotide rs25531
entrambi situati nella regione 5'UTR; è noto che questi polimorfismi agiscono ambedue, seppur con meccanismi diversi,
sull 'efficacia trascrizionale di questo gene.
Materiali e metodi: Il genotipo relativo ai due polimorfismi in studio è stato caratterizzato, con metodiche di PCR e single
nucleotide primer extension, in una popolazione composta da 403 pazienti ambulatoriali alcol-dipendenti e da 427 soggetti
di controllo donatori di sangue del centro trasfusionale dell'Azienda Policlinico Umberto I di Roma.
Risultati : Abbiamo riscontrato un'associazione significativa tra il polimorfismo 5-HTTLPR e la popolazione alcol-dipendente
di sesso femminile che ha cominciato a bere in giovane eta (<25 anni) , con una odds ratio di 1,8 per I'allele L ed un valore
di probabilità associato di 0,026 ; una odds ratio di 2,2 è risultata per il genotipo LL, quello trascrizionalmente più attivo, con
un valore di probabilltà associato di 0,034. Nessuna differenza statisticamente significativa è emersa per il polimorfismo
rs25531 ne, a parte i risultati già descritti, per il polimorfismo 5-HTTLPR nella sua forma bi-allelica nonché in quella triallelica in associazione con il polimorfismo rs25531.
Conclusioni: I nostri risultati suggeriscono che differenze di genere e nell'eta di insorgenza della alcol-dipendenza possano
essere in relazione con fattori genetici
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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