33 research outputs found

    A Flow Induced Autoimmune Response and Accelerated Senescence of Red Blood Cells in Cardiovascular Devices

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    Red blood cells (RBCs) passing through heart pumps, prosthetic heart valves and other cardiovascular devices undergo early senescence attributed to non-physiologic forces. We hypothesized that mechanical trauma accelerates aging by deformation of membrane proteins to cause binding of naturally occurring IgG. RBCs isolated from blood of healthy volunteers were exposed to high shear stress in a viscometer or microfluidics channel to mimic mechanical trauma and then incubated with autologous plasma. Increased binding of IgG was observed indicating forces caused conformational changes in a membrane protein exposing an epitope(s), probably the senescent cell antigen of band 3. The binding of immunoglobulin suggests it plays a role in the premature sequestration and phagocytosis of RBCs in the spleen. Measurement of IgG holds promise as a marker foreshadowing complications in cardiovascular patients and as a means to improve the design of medical devices in which RBCs are susceptible to sublethal trauma.Research in this publication was supported by the National Institutes of Health Small Business Innovation Research program under award number R44HL114246 as a subcontract to the University of Oklahoma from VADovations and NIH grant R21HL132286 to DWS and TAS. Open Access fees paid for in whole or in part by the University of Oklahoma Libraries.Ye

    Development of optimal strategies for water harvesting and utilization in arid lands, Jordan

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    In IDL-987

    Effects of land use changes and soil conservation intervention on soil properties as indicators for land degradation under a Mediterranean climate

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    Land degradation resulting from improper land use and management is a major cause of declined productivity in the arid environment. The objectives of this study were to examine the effects of a sequence of land use changes, soil conservation measures, and the time since their implementation on the degradation of selected soil properties. The climate for the selected 105 km<sup>2</sup> watershed varies from semi-arid sub-tropical to Mediterranean sub-humid. Land use changes were detected using aerial photographs acquired in 1953, 1978, and 2008. A total of 218 samples were collected from 40 sites in three different rainfall zones to represent different land use changes and variable lengths of time since the construction of stone walls. Analyses of variance were used to test the differences between the sequences of land use changes (interchangeable sequences of forest, orchards, field crops, and range), the time since the implementation of soil conservation measures, rainfall on the thickness of the A-horizon, soil organic carbon content, and texture. Soil organic carbon reacts actively with different combinations and sequences of land use changes. The time since stone walls were constructed showed significant impacts on soil organic carbon and the thickness of the surface horizon. The effects of changing the land use and whether the changes were associated with the construction of stone walls varied according to the annual rainfall. The changes in soil properties could be used as indicators of land degradation and to assess the impact of soil conservation programs. The results help in understanding the effects of land use changes on land degradation processes and carbon sequestration potential and in formulating sound soil conservation plans

    Association of timing of percutaneous left ventricular assist device insertion with outcomes in patients undergoing cardiac surgeryCentral MessagePerspective

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    Objectives: The aim of this study was to explore the associations between percutaneous ventricular assist device (pVAD) insertion timing relative to cardiac surgery and patient outcomes. Methods: The Nationwide Inpatient Sample was queried for patients undergoing cardiac surgery and pVAD insertion in the same admission from 2016 to 2019. Patients were stratified by timing of pVAD insertion. Preoperative characteristics, postoperative complications, and mortality were compared among groups. Results: Overall, 3695 patients underwent cardiac surgery and pVAD insertion during the same hospitalization (pre: 1130, intra: 1690, and post: 875). The distribution of cardiac surgery procedures was similar across groups. Median Elixhauser Comorbidity Index was 13 for pre-, 15 for intra-, and 17 for postoperative pVAD patients (P = .021). Patients who received a postoperative pVAD were associated with increased mortality (pre: 18%, intra: 39%, and post: 54%; P < .01). Increased complication rates were also associated with postoperative pVAD insertion (pre: 61%, intra: 55%, and post: 75%; P < .01). Preoperative pVAD insertion was associated with increase rates of sepsis (pre: 18%, intra: 9.8%, and post: 17%; P = .01) and pneumonia (pre: 38%, intra: 23%, and post: 31%; P < .01). Postoperative pVAD insertion was associated with increased rates of gastrointestinal bleeding (pre: 2.2%, intra: 3.0%, and post: 7.4%; P = .01), renal failure (pre: 10%, intra: 9.2%, and post: 17%; P = .01), and prolonged ventilation (pre: 44%, intra: 41%, and post: 54%; P = .02). Conclusions: Postoperative pVAD insertion following cardiac surgery was associated with increased complications and mortality compared with preoperative or intraoperative insertion. Further studies should explore optimal utilization and timing of pVAD insertion in patients undergoing cardiac surgery

    White donor, younger donor and double lung transplant are associated with better survival in sarcoidosis patients

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    Sarcoidosis commonly affects the lung. Lung transplantation (LT) is required when there is a severe and refractory involvement. We compared post-transplant survival rates of sarcoidosis patients with chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF). We also explored whether the race and age of the donor, and double lung transplant have any effect on the survival in the post transplant setting. We analyzed 9,727 adult patients with sarcoidosis, COPD, and IPF who underwent LT worldwide between 2005-2015 based on United Network for Organ Sharing (UNOS) database. Survival rates were compared with Kaplan-Meier, and risk factors were investigated by Cox-regression analysis. 469 (5%) were transplanted because of sarcoidosis, 3,688 (38%) for COPD and 5,570 (57%) for IPF. Unadjusted survival analysis showed a better post-transplant survival rate for patients with sarcoidosis (p < 0.001, Log-rank test). In Cox-regression analysis, double lung transplant and white race of the lung donor showed to have a significant survival advantage. Since double lung transplant, those who are younger and have lower Lung Allocation Score (LAS) at the time of transplant have a survival advantage, we suggest double lung transplant as the procedure of choice, especially in younger sarcoidosis subjects and with lower LAS scores
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