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Effect of Butyrate in the Healing of Colonic Anastomoses in Rats
Get PDFBACKGROUND:
The body’s ability to replace injured or dead cells and repair tissues following inflammation is critical to survival. The repair of tissues involves two distinct processes – replacement of injured or dead cells by cells of the same type or regeneration and replacement by connective tissue called fibroplasia or fibrosis. Both these processes are determined by essentially similar mechanisms involving cell migration, proliferation and differentiation as well as cell-matrix interactions. The orderly regeneration of epithelial tissue requires a
specialised extracellular matrix called the basement membrane which acts as a scaffolding. These processes are the basis of the complex phenomenon of wound healing.
AIMS AND OBJECTIVES:
1. To assess the effect of intraluminal butyrate on the healing of anastomoses in rat colon by testing mechanical strength.
2. To compare the differences in the mechanical strength of ascending and descending colon with and without treatment with butyrate.
3. To assess the expression of Matrix Metalloproteinases in the healing colon and study the effect of butyrate on this expression.
MATERIALS AND METHODS:
Forty male albino rats of the Wistar strain weighing between 200 – 250 grams were used for the experiment. The animals were fed a fibre-free diet to minimise the production of SCFAs from the fibre in the colon. This was begun 2 days before the initial operation and continued till the end of the experiment. The diet used was a specially prepared purified fibre free diet based on the American Institute of Nutrition (AIN)-93M diet.105 The diet was prepared initially in a powder form and reconstituted every day with water to make a semi-solid diet. After 48 hours, the rats were anaesthetised using ether chamber and
intra-peritoneal ketamine (50mg/kg) and a midline laparotomy was done. The colon was first washed out with normal saline and then transected in two places preserving the marginal vessels (Fig 6.1). The ascending colon was transected about 3 cms from the ileo-caecal junction and the descending colon about 3 cms from the peritoneal reflection. Specimens were taken from both areas, frozen immediately in liquid nitrogen and stored at -70°C. An end-to-end anastomosis was carried out with a single layer of interrupted 6. 0 proline sutures (Fig 6.2, 6.3). A diversion caecostomy was carried out and the abdomen
closed in layers.
Statistical Analysis:
The results were tabulated on a spreadsheet and statistical analysis was done using SPSS software.
RESULTS:
Of the 40 rats used, 9 died during the course of the experiment. Six rats died during anaesthesia or in the immediate post-operative period. Of these, 4 animals died in the ether chamber possibly due to a reaction to ether or a vasovagal attack. One animal did not wake up after the operation and another animal died of acute cardiac tamponade as the post operative dose of saline was injected into the thorax instead of subcutaneously. Three animals died during the post operative period. One died on the first post-operative day possibly due to aspiration and two died on the fifth post-operative day due to intestinal obstruction. There were no demonstrable anastomotic leaks during the study.
CONCLUSIONS:
1. Local instillation of butyrate significantly strengthens colonic anastomoses as measured by the bursting wall tension.
2. The effect of butyrate increases both the bursting pressure and the circumference of the anastomosis.
3. There is a difference in the strength of proximal and distal colonic anastomoses.
4. There was an increase in the expression of Matrix metalloproteinases in all the post operative specimens. There was no difference in the expression of MMP2, but an increase in the expression of MMP9 between the butyrate and saline arms
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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