1,721,045 research outputs found
Characterization of a novel T lymphocyte protein which binds to a site related to steroid/thyroid hormone receptor response elements in the negative regulatory sequence of the human immunodeficiency virus long terminal repeat
No full textWe have previously identified a T lymphocyte protein which binds to a site within the LTR of the human immunodeficiency virus type 1 (HIV-1) and exerts an inhibitory effect on virus gene expression. The palindromic site (site B) recognized by this protein is related to the palindromic binding sites of members of the steroid/thyroid hormone receptor family. Here we characterize the T cell protein binding to this site as a 100 kD protein which is most abundant in T cells and which binds to site B as a 200 kD complex. This protein is distinct from other members of the steroid/thyroid hormone receptor family including the COUP protein which has a closely related DNA binding specificity.</p
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
The transcriptional co-activators CBP and p300 are activated via phenylephrine through the p42/p44 MAPK cascade
No full textThe CBP and p300 co-activators play a key role in many aspects of gene regulation being recruited to the DNA via transcription factors that are targets for specific signaling pathways. It has previously been demonstrated that in neuronal cells the ability of CBP and p300 to activate transcription can be directly stimulated by nerve growth factor or calcium-activated signaling pathways. Here we demonstrate that, in cardiac cells, the activity of CBP and p300 is stimulated by phenylephrine (PE) treatment and that they are required for the activation of atrial naturetic factor (ANF) gene expression by PE. Activation of CBP/p300 by PE involves the p42/p44 MAPK pathway and targets primarily the N terminus of p300 and the C terminus of CBP, which are not homologous to one another. To our knowledge, this is the first report of a specific stimulus modulating the activity of CBP and p300 in cardiac cells and it suggests that these factors play an important role in the hypertrophic effect of PE
Detection in non-erythroid cells of a factor with the binding characteristics of the erythroid cell transcription factor EF1
No full textThe erythroid transcription factor erythroid factor-1 (EF1) plays a critical role in the transcription of erythroid-specific genes. Here we report the presence of a factor with the mobility and sequence-specific DNA-binding characteristics of EF1 at low abundance in a wide variety of non-erythroid cell types. This is the first report of an EF1-like activity in non-erythroid cells and indicates that this factor may play a role in the regulation of genes expressed in such cells.</p
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
A novel T-cell protein which recognizes a palindromic sequence in the negative regulatory element of the human immunodeficiency virus long terminal repeat
No full textTwo major protein-binding sites within the negative regulatory element of the human immunodeficiency virus type 1 long terminal repeat have been identified. One (site B) contained a palindromic sequence with homology to steroid/thyroid hormone response elements but was distinct from previously described binding sites of this class. A novel T-cell protein recognized the palindromic sequence within site B and also bound estrogen- or thyroid hormone-response elements with lower affinity. A 7-base-pair mutation in the site B palindrome, which destroyed protein binding, resulted in increased expression from the human immunodeficiency virus type 1 long terminal repeat in T cells.</p
A T-cell protein which recognizes a palindromic DNA sequence in the negative regulatory element of the HIV-1 long terminal repeat with homology to steroid/thyroid hormone receptor binding sites
No full textDispelling 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
- …
