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Isolation and characterization of a novel collagen-binding protein from Streptococcus pyogenes strain 6414
No full text
Isolation and characterization of a novel collagen-binding protein from Streptococcus pyogenes strain 6414
No full textIn this report we have analyzed the binding of collagen to Streptococcus pyogenes strain 6414. This binding was rapid, specific, and involved a limited number of receptor molecules (11,600 copies per cell). When the proteins in a streptococcal lysate were blotted onto a nitrocellulose filter and probed with 125I-labeled collagen, a prominent collagen-binding protein of 57 kDa was identified as well as minor 130-150-kDa components. The major 57-kDa protein was isolated by affinity chromatography on collagen-Sepharose followed by gel filtration chromatography. The 57-kDa protein purified from S. pyogenes was used to raise a monospecific antibody which also reacted with a collagen-binding protein of similar molecular size isolated from Streptococcus zooepidemicus. The two collagen-binding proteins from streptococci have a similar amino acid composition and isoelectric points. Isolated collagen-binding protein was specifically recognized by 125I-collagen in a solid-phase binding assay and displayed an affinity for the ligand quite similar to that exhibited by intact bacteria (Kd = 3.1 versus 3.5 x 10(-9) M, respectively). Surface-labeled bacteria attached to microtiter wells coated with different collagen types and the 57-kDa protein blocked the adhesion to collagen substrate. We propose that the 57-kDa protein is an adhesin involved in the attachment of streptococci to host tissues
Interaction of genetic markers of inflammation and multiple risk factors in CAD (Coronary Artery Disease)
No full textGoing 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
Atrial fibrillation recurrence and expression levels of apelin-regulating miRNAs
No full textMicroRNAs have emerged as novel serum diagnostic biomarkers for various diseases. To understand the mechanisms of atrial fibrillation (AF), we are studying apelin-regulating miRNAs that might identify those individuals with an increased propensity to the arrhythmia.
We recruited 68 patients with persistent or chronic AF. Of the 68 patients with AF, 38 present a persistent AF and underwent external electrical cardioversion. Quantitative Real-time PCR was performed with LNA probes and SYBR master mix for apelin-regulating miRNAs. High expression of hsa-miR-30b-5p (0.29-fold), hsa-miR-30c-5p (0.15-fold), hsa-miR-155-5p (0.29-fold), hsa-miR-142-3p (0.63-fold), hsa-miR-148-3p (0.13-fold) and hsa-miR-124-3p (1.2-fold) was found in AF group as compared to controls. Comparing the values of relative quantification among patients with AF recurrence after external electrical cardioversion and patients who maintained sinus rhythm we found a statistically significant difference only for the miR-30b-5p. Our studies confirm the hypothesis that apelin and apelinergic system plays a role in the pathophysiology of AF. The determination of cut-off values for miRNAs involved in the regulation of apelin could allow the creation of an effective prognostic score that can be useful to determine which therapeutic strategy to adopt in each patient according to his chances of
maintaining the pace before cardioversion external power supply
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
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