Browsing by Author "Gray, Alan"

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    Age of Transfused Red Blood Cells and Health Outcomes in Two Surgical Cohorts
    (Elsevier, 2019-03) Khan, Sikandar H.; Devnani, Rohit; LaPradd, Michelle; Landrigan, Matt; Gray, Alan; Kelley, Andrea; Eckert, George J.; Li, Xiaochun; Khan, Babar A.; Medicine, School of Medicine
    Rationale: Red blood cells (RBC) undergo morphologic and biochemical changes during storage which may lead to adverse health risks upon transfusion. In prior studies, the effect of RBC age on health outcomes has been conflicting. We designed the study to assess the effects of RBC units' storage duration on health outcomes specifically for hospitalized patients undergoing hip fracture surgery or coronary artery bypass grafting (CABG) surgery. Methods: Using International Classification of Diseases (ICD) 9 codes, hip fracture surgery and CABG surgery patients, who received RBC transfusions between 2008 and 2013, were retrospectively identified from the electronic medical records system. Hip fracture surgery and CABG cohorts were sub-divided into 3 blood age groups based upon RBC unit age at the time of transfusion: young blood (RBC units stored less than or equal to 14 days), old blood (RBC units were stored for greater than or equal to 28 days), or mixed blood for the remaining patients. Outcome variables were 30-day, 90-day, and inpatient mortality as well as hospital length of stay. Results: A total of 3,182 patients were identified: 1,121 with hip fractures and 2,061 with CABG. Transfusion of old blood was associated with higher inpatient mortality in the hip fracture surgery cohort (OR 166.8, 95% CI 1.067-26064.7, p = 0.04) and a higher 30-day mortality in the CABG cohort (OR 4.55, 95% CI 1.01-20.49, p = 0.03). Conclusions: Transfusing RBC units stored for greater than or equal to 28 days may be associated with a higher mortality for patients undergoing hip fracture or CABG.
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    Isotopic evidence for oligotrophication of terrestrial ecosystems
    (Nature, 2018) Craine, Joseph; Elmore, Andrew J.; Wang, Lixin; Aranibar, Julieta; Bauters, Marijn; Boeckx, Pascal; Crowley, Brooke E.; Dawes, Melissa A.; Delzon, Sylvain; Fajardo, Alex; Fang, Yunting; Fujiyoshi, Lei; Gray, Alan; Guerrieri, Rossella; Gundale, Michael J.; Hawke, David J.; Hietz, Peter; Jonard, Mathieu; Kearsley, Elizabeth; Kenzo, Tanaka; Makarov, Mikhail; Marañón-Jiménez, Sara; McGlynn, Terrence P.; McNeil, Brenden E.; Mosher, Stella G.; Nelson, David M.; Peri, Pablo L.; Roggy, Jean Christophe; Sanders-DeMott, Rebecca; Song, Minghua; Szpak, Paul; Templer, Pamela H.; Van der Colff, Dewidine; Werner, Christiane; Xu, Xingliang; Yang, Yang; Yu, Guirui; Zmudczyńska-Skarbek, Katarzyna; Earth Sciences, School of Science
    Human societies depend on an Earth system that operates within a constrained range of nutrient availability, yet the recent trajectory of terrestrial nitrogen (N) availability is uncertain. Examining patterns of foliar N concentrations and isotope ratios (δ15N) from more than 43,000 samples acquired over 37 years, here we show that foliar N concentration declined by 9% and foliar δ15N declined by 0.6–1.6‰. Examining patterns across different climate spaces, foliar δ15N declined across the entire range of mean annual temperature and mean annual precipitation tested. These results suggest declines in N supply relative to plant demand at the global scale. In all, there are now multiple lines of evidence of declining N availability in many unfertilized terrestrial ecosystems, including declines in δ15N of tree rings and leaves from herbarium samples over the past 75–150 years. These patterns are consistent with the proposed consequences of elevated atmospheric carbon dioxide and longer growing seasons. These declines will limit future terrestrial carbon uptake and increase nutritional stress for herbivores.