1,720,961 research outputs found
Polymorphisms at the glutathione S-transferase, GSTP1 locus: a novel mechanism for susceptibility and development of atopic airway inflammation
No full textA common feature of environmental irritants is their ability to cause local inflammation which could alter airway function. The principal targets of such injury are the epithelial cells lining the airway passages and the lower respiratory gas-exchange areas. While host atopy is a recognized risk factor for airway inflammation, atopy alone cannot cause asthma. We hypothesize that susceptibility to persistent airway inflammation in atopic individuals is characterized by an inherited deficiency in the effectiveness of detoxification of inhaled irritants and products of oxidative stress such as reactive oxygen species (ROS). Our case-control studies show that polymorphisms at the glutathione S-transferase, GSTP1, locus on chromosome 11q13 may account for variation in host response to oxidative stress, a key component of airway inflammation. Frequency of the GSTP1 Val/Val genotype is reduced in atopic subjects compared with nonatopic subjects. Trend analysis also shows a significant decrease of GSTP1 Val/Val (with parallel increase of GSTP1 Ile/Ile) genotype frequency with increasing severity of airflow obstruction/bronchial hyperresponsiveness. The implication of specific polymorphisms at the GSTP1 locus in airway inflammation is entirely novel: however, GST are recognized as a supergene family of enzymes critical in 1) cell protection from the toxic products of ROS-mediated reactions, 2) modulation of eicosanoid synthesis
Polymorphism at the glutathione S-transferase, GSTP1 locus:A new marker for bronchial hyperresponsiveness and asthma
No full textMost genetic studies of asthma have concentrated on genes on chromosomes 11q and 5q and their association with the key asthma-related phenotypes of bronchial hyperresponsiveness (BHR) and atopy. Although asthma is characterized by airway inflammation, a critical component of which is oxidative stress, few data exist on genes involved in protecting against this insult. We describe an association study designed to examine whether allelic variation at the glutathione-S-transferase GSTP1 locus influences expression of the BHR and atopy phenotypes in asthma. The enzyme encoded by GSTP1 utilizes a variety of lipid and DNA products of oxidative stress, and polymorphic variants of this gene are associated with altered catalytic function of this enzyme. We found that the frequency of GSTP1 Val(105)/Val(105) was significantly lower in asthmatic than in control subjects. Indeed, the presence of this genotype conferred a sixfold lower risk of asthma than did GSTP1 Ile(105)/Ile(105). Remarkably, asthma risk in Val(105) homozygotes was further reduced (by ninefold) after correction for atopic indices, age, and gender. Trend analysis after stratification according to the degree of bronchial reactivity/obstruction showed that the frequency of GSTP1 Val(105)/Val(105) correlates with decreasing severity of airway dysfunction. Furthermore, subjects with GSTP1 Val(105)/Val(105) have four- and 10-fold lower risks, respectively, of exhibiting atopy defined by skin test positivity and IgE level. These data show that GSTP1 polymorphism is strongly associated with asthma and related phenotypes, and provide an alternative explanation for the linkage of chromosome 11q13 with BHR and atopy
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
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
MSO899695 Supplemental Figure - Supplemental material for Th17 cells increase in RRMS as well as in SPMS, whereas various other phenotypes of Th17 increase in RRMS only
No full textSupplemental material, MSO899695 Supplemental Figure for Th17 cells increase in RRMS as well as in SPMS, whereas various other phenotypes of Th17 increase in RRMS only by S Kalra, C Lowndes, L Durant, RC Strange, A Al-Araji, Clive P Hawkins and S John Curnow in Multiple Sclerosis Journal—Experimental, Translational and Clinical</p
MSO899695 Supplemental material - Supplemental material for Th17 cells increase in RRMS as well as in SPMS, whereas various other phenotypes of Th17 increase in RRMS only
No full textSupplemental material, MSO899695 Supplemental material for Th17 cells increase in RRMS as well as in SPMS, whereas various other phenotypes of Th17 increase in RRMS only by S Kalra, C Lowndes, L Durant, RC Strange, A Al-Araji, Clive P Hawkins and S John Curnow in Multiple Sclerosis Journal—Experimental, Translational and Clinical</p
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
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