196,150 research outputs found
MECHANISMS OF HYDROPEROXIDE-INDUCED BRONCHOCONSTRICTION AND VASOCONSTRICTION IN ISOLATED AND PERFUSED RAT LUNG
No full textThe mechanisms of hydroperoxide-induced broncho- and vasoconstriction were investigated in the perfused and ventilated rat lung. Hydrogen peroxide (500 mu-M), tertiary butylhydroperoxide (500 mu-M) and arachidonic acid (100 mu-M) induced similar profiles of broncho- and vasoconstriction which could be prevented by the inhibitor of cyclooxygenase, diclofenac (100 mu-M) but not by nordihydroguaiaretic acid (5 and 25 mu-M), an inhibitor of lipoxygenase. The hydroperoxides also caused a time-dependent increase in the levels of thromboxane and prostacycline, products of cyclooxygenase. Furthermore, the thromboxane agonist, U44069 (100 pmoles), caused a very rapid broncho- and vasoconstriction that was preventable by the thromboxane antagonist L655.240 (1 mu-M). L655.240 also inhibited hydrogen peroxide-induced broncho- and vasoconstriction. The phospholipase A2 inhibitors, quinacrine (100 mu-M) and dibucaine (100 mu-M), did not prevent hydroperoxide-induced broncho- and vasoconstriction. The Ca2+ chelator, EGTA, prevented hydroperoxide and arachidonic acid-induced lung constriction, although it did not inhibit the release of thromboxane. The infusion of arachidonic acid and hydroperoxides resulted in edema in the lung which was prevented by prior administration of diclofenac, indomethacin or L655.240. These results indicate that hydroperoxide-induced broncho- and vasoconstriction and lung edema are mediated by thromboxane, a product of cyclooxygenase. The mechanism of hydroperoxide-induced release of arachidonic acid is not clear but does not seem to involve Ca2+ nor the activation of phospholipase A2
USE OF TRITIUM LABELED AMINO ACID CONJUGATES OF PROSTAGLANDINS AND THROMBOXANE AS LABELED LIGANDS IN PROSTANOID RADIOIMMUNOASSAY.
No full textUSE OF TRITIUM LABELED AMINO ACID CONJUGATES OF PROSTAGLANDINS AND THROMBOXANE AS LABELED LIGANDS IN PROSTANOID RADIOIMMUNOASSAY.
No full textMesenchymal stem cell regeneration and differentiation after anti inflammatory drug exposure
No full textTraumatic and degenerative pathologies of the musculoskeletal system are common and often involve injuries of multiple mesenchymal tissues including bone, cartilage, tendons and ligaments. Medical intervention is frequently initiated to relieve pain, restore biomechanical function, with aim to return to the desired level of activity as soon as possible. Oral or locally administered symptomatic pain relief has been used for a very long time, with little or no consideration of the long-term consequences on regeneration or optimizing healing properties of the synovial joint. Commonly used drugs are non-steroid-anti-inflammatory drugs (NSAIDS), aswell as locally injected glucocorticoids, administred peri- or intra articular when oral analgetics are insufficient. The focus of this thesis was to deeper explore the impact of short time exposure of two commonly used anti-inflammatory drugs i.e diclofenac (DF) and triamcinolone acetonide (TA) on mesenchymal stem cell (MSC) viability, differentiation capacity and trancriptomic output. Effect of tenogenic inducing growth factor GDF-7 on MSC differentiation was also assessed.The results of a murine model system showed the significantly reduced growth of MSCs exposed to TA and DF in therapeutical concentrations, in a concentration- and time dependent manner, however the growth inhibitory effect of DF was significantly reduced only in high concentrations. MSCs exposed to GDF-7 showed increased expression of tenogenic marker tenomodulin. Concomitant exposure of MSCs to GDF-7 and TA increased adipogenesis unpremeditatedly in a time dependent manner. Further studies were performed on primary human bone marrow MSC growth (hBM-MSC) where TA exerted a time- and dose dependent negative impact on hBM-MSCs. In addition, TA impaired cell cycle regulation and DNA replication, increased apoptotic/late-apoptotic cells significantly in TA-exposed cells. Differentiation assays after TA exposure revealed upregulation of osteoblastic marker RUNX2, but no significant difference after osteoblastic differentiation of hBM-MSCs exposed to TA or control. Adipogenesis was spontaneously induced by TA and could be confirmed both molecular and functional and TA clearly impaired chondrogenic differentiation demonstrated by molecular- and functional assays. The anti-inflammatory glucocorticoid stimulus on hBM-MSCs was verified with impaired inflammatory response. TA also reduced hBM-MSC activation, pointing to several functional mechanisms altered in the MSC immunoresponse to TA.In concusion, the results from this thesis raise the awareness of unpremeditated negative trophic effects of the synovial joint tissue when treating with the anti- inflammatory drugs triamcinolone acetonide and diclofenac, aiming at relieving pain. The side-effects are significant, impairing regeneration and chondrogenesis while promoting adipogenesis.List of scientific papersI. Diclofenac and triamcinolone acetonide impair tenocytic differentiation and promote adipocytic differentiation of mesenchymal stem cells. Fredriksson M, Li Y, Stålman A, Haldosén LA, Felländer-Tsai L. J Orthop Surg Res. 2013 Sep 2;8:30. https://doi.org/10.1186/1749-799X-8-30 II. Growth Differentiation Factor 7 promotes multiple-lineage differentiation in tenogenic cultures of mesenchymal stem cells. Kumlin M, Lindberg K, Haldosen LA, Felländer-Tsai L, Li Y. Injury. 2022 Dec;53(12):4165-4168. https://doi.org/10.1016/j.injury.2022.09.017 III. The functional and molecular impact of triamcinolone acetonide on primary human bone marrow mesenchymal stem cells. Kumlin M, Ungerstedt J, Cai H, Leonard E, Felländer-Tsai L, Qian H. [Submitted]IV. Molecular evidence for the effect of diclofenac on human mesenchymal stem cell survival and differentiation. Kumlin M, Ungerstedt J, Cai H, Felländer-Tsai L, Qian H. [Manuscript]</p
Arachidonic acid metabolism in the human mast cell line HMC-1. 5-lipoxygenase gene expression and biosynthesis of thromboxane
No full textDr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dispelling the Myths Behind First-author Citation Counts
No full textWe 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
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
Simulation of thermal plant optimization and hydraulic aspects of thermal distribution loops for large campuses
No full textFollowing an introduction, the author describes Texas A&M University and its utilities system. After that, the author presents how to construct simulation models for chilled water and heating hot water distribution systems. The simulation model was used in a $2.3 million Ross Street chilled water pipe replacement project at Texas A&M University. A second project conducted at the University of Texas at San Antonio was used as an example to demonstrate how to identify and design an optimal distribution system by using a simulation model. The author found that the minor losses of these closed loop thermal distribution systems are significantly higher than potable water distribution systems. In the second part of the report, the author presents the latest development of software called the Plant Optimization Program, which can simulate cogeneration plant operation, estimate its operation cost and provide optimized operation suggestions. The author also developed detailed simulation models for a gas turbine and heat recovery steam generator and identified significant potential savings. Finally, the author also used a steam turbine as an example to present a multi-regression method on constructing simulation models by using basic statistics and optimization algorithms. This report presents a survey of the author??s working experience at the Energy Systems Laboratory (ESL) at Texas A&M University during the period of January 2002 through March 2004. The purpose of the above work was to allow the author to become familiar with the practice of engineering. The result is that the author knows how to complete a project from start to finish and understands how both technical and nontechnical aspects of a project need to be considered in order to ensure a quality deliverable and bring a project to successful completion. This report concludes that the objectives of the internship were successfully accomplished and that the requirements for the degree of Degree of Engineering have been satisfied
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