1,721,176 research outputs found
Significantly decreased hypoxanthine levels in bone marrow plasma of aplastic anemia patients revealed by 800 MHz NMR based metabolomics analysis
No full textBackground: Compared to plasma, the hypoxanthine (HX) concentration is three times higher in the human bone marrow [R1] and its availability is crucial to regulate the de novo purine synthesis in human bone marrow in vivo [R1]. Studies have shown that circulatory HX levels in the plasma increase in patients with solid tumors and leukemia [R2]. Aplastic anemia (AA) is rare disorder of bone marrow failure characterized by hypocellularity and peripheral cytopenias. As purine biosynthesis is essential for normal cell growth and proliferation, we hypothesized that bone marrow HX levels will be decreased in aplastic anemia (AA) patients and may reset back partially in AA patients showing clinical improvement.
Aim: To compare the HX levels in bone marrow plasma samples of AA patients and control subjects and further to check its metabolic reprogramming in AA patients showing clinical improvement.
Methods: The HX levels of bone marrow plasma metabolites were estimated for 56 AA patients and 20 control subjects using 800 MHz NMR spectroscopy. The NMR spectra were analyzed using NMR suite of commercial software (CHENOMX). The levels of altered metabolites in AA patients w.r.t control were estimated and the values are reported as Mean ± SD (SD is standard deviation). The diagnostic potential is evaluated employing standard receiver operating characteristic (ROC) curve analysis.
Results: The present study aims to compare the bone marrow plasma metabolic profiles of hypoxanthine between age and sex matched AA patients (N=40; mean age 32.31±16.03, male/female ratio of 22/18) and follow-up AA patients (N=16) with respect to age matched control subjects (N=20, mean age=39.5±18.48 years, male/female ratio of 11/9). The comparison revealed that the HX levels are significantly decreased in AA patients (HX=3.62 ± 3.17) compared to NC subjects (HX = 20.89 ± 12.73) and improved slightly in follow-up patients (HX=6.21 ±4.77, however no statistically significant change compared to AA patients). Further, the circulatory HX levels exhibit significant diagnostic potential with area under ROC (AUROC) curve values equal to 0.96 [95%CI = 0.92–1.00].
Concluding remarks: The depleted HX levels in the bone marrow plasma suggested altered/compromised purine biosynthesis/metabolism in AA patients and future studies are warranted to underscore its role in the disease pathobiology.
Reference:
[R1] King, M.E., Honeysett, J.M. and Howell, S.B., 1983. Regulation of de novo purine synthesis in human bone marrow mononuclear cells by hypoxanthine. The Journal of clinical investigation, 72(3), pp.965-970.
[R2] Wung WE, Howell SB. Hypoxanthine concentrations in normal subjects and patients with solid tumors and leukemia. Cancer research. 1984 Jul;44(7):3144-8.Compared to control subjects, the multivariate statistical analysis revealed that there are significantly decreased levels of hypoxanthine, citrate, lactate and glutamine in the bone marrow plasma of AA patients. On the other hand, the circulatory levels of acetate and pyruvate were significantly increased in the bone marrow plasma samples of AA patients compared to control subjects.
The investigation is an extension of our previous study
Srivastava, Jyotika, Shobhita Katiyar, Chandra P. Chaturvedi, and Soniya Nityanand. "Extracellular vesicles from bone marrow mesenchymal stromal cells of severe aplastic anemia patients attenuate hematopoietic functions of CD34+ hematopoietic stem and progenitor cells." Cell Biology International 46, no. 11 (2022): 1970-1976
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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