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Chen F, Ritter M, Xu Y, Tu K, Koch SM, Yan W, Bian H, Ding Y, Sun J, Burgert I. Lightweight, Strong, and Transparent Wood Films Produced by Capillary Driven Self-Densification. Small 2024:e2311966. [PMID: 38770995 DOI: 10.1002/smll.202311966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 04/16/2024] [Indexed: 05/22/2024]
Abstract
Wood delignification and densification enable the production of high strength and/or transparent wood materials with exceptional properties. However, processing needs to be more sustainable and besides the chemical delignification treatments, energy intense hot-pressing calls for alternative approaches. Here, this study shows that additional softening of delignified wood via a mild swelling process using an ionic liquid-water mixture enables the densification of tube-line wood cells into layer-by-layer sheet structures without hot-pressing. The natural capillary force induces self-densification in a simple drying process resulting in a transparent wood film. The as-prepared films with ≈150 µm thickness possess an optical transmittance ≈70%, while maintaining optical haze >95%. Due to the densely packed sheet structure with a large interfacial area, the reassembled wood film is fivefold stronger and stiffer than the delignified wood in fiber direction. Owing to a low density, the specific tensile strength and elastic modulus are as high as 282 MPa cm3 g-1 and 31 GPa cm3 g-1. A facile and highly energy efficient wood nanotechnology approach are demonstrated toward more sustainable materials and processes by directly converting delignified wood into transparent wood omitting polymeric matrix infiltration or mechanical pressing.
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Affiliation(s)
- Feng Chen
- Hubei Provincial Engineering Research Center of Surface and Interface Regulation Technology and Equipment for Renewable Energy Materials, Jianghan University, Wuhan, 430056, China
- Key Laboratory of Optoelectronic Chemical Materials and Devices-Ministry of Education, Jianghan University, Wuhan, 430056, China
- Wood Materials Science Group, Institute for Building Materials, ETH Zürich, Zürich, 8093, Switzerland
| | - Maximilian Ritter
- Wood Materials Science Group, Institute for Building Materials, ETH Zürich, Zürich, 8093, Switzerland
- WoodTec Group, Cellulose & Wood Materials, Empa, Dübendorf, 8600, Switzerland
| | - Yifan Xu
- Hubei Provincial Engineering Research Center of Surface and Interface Regulation Technology and Equipment for Renewable Energy Materials, Jianghan University, Wuhan, 430056, China
- Key Laboratory of Optoelectronic Chemical Materials and Devices-Ministry of Education, Jianghan University, Wuhan, 430056, China
| | - Kunkun Tu
- Wood Materials Science Group, Institute for Building Materials, ETH Zürich, Zürich, 8093, Switzerland
- WoodTec Group, Cellulose & Wood Materials, Empa, Dübendorf, 8600, Switzerland
- Jiangsu Key Laboratory of Coal-based Greenhouse Gas Control and Utilization, China University of Mining and Technology, Xuzhou, Jiangsu, 221008, China
| | - Sophie Marie Koch
- Wood Materials Science Group, Institute for Building Materials, ETH Zürich, Zürich, 8093, Switzerland
- WoodTec Group, Cellulose & Wood Materials, Empa, Dübendorf, 8600, Switzerland
| | - Wenqing Yan
- Wood Materials Science Group, Institute for Building Materials, ETH Zürich, Zürich, 8093, Switzerland
| | - Huiyang Bian
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China
| | - Yong Ding
- Wood Materials Science Group, Institute for Building Materials, ETH Zürich, Zürich, 8093, Switzerland
- WoodTec Group, Cellulose & Wood Materials, Empa, Dübendorf, 8600, Switzerland
| | - Jianguo Sun
- Wood Materials Science Group, Institute for Building Materials, ETH Zürich, Zürich, 8093, Switzerland
- WoodTec Group, Cellulose & Wood Materials, Empa, Dübendorf, 8600, Switzerland
| | - Ingo Burgert
- Wood Materials Science Group, Institute for Building Materials, ETH Zürich, Zürich, 8093, Switzerland
- WoodTec Group, Cellulose & Wood Materials, Empa, Dübendorf, 8600, Switzerland
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Guan H, Zhang C, Tu K, Dai X, Wang X, Wang X. Wet-Stable Lamellar Wood Sponge with High Elasticity and Fatigue Resistance Enabled by Chemical Cross-Linking. ACS Appl Mater Interfaces 2024; 16:18173-18183. [PMID: 38557017 DOI: 10.1021/acsami.4c01173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The excessive consumption of fossil-based plastics and the associated environmental concerns motivate the increasing exploitation of sustainable biomass-based materials for advanced applications. Natural wood-derived lamellar wood sponges via a top-down approach have recently attracted significant attention; however, the insufficient compressive fatigue resistance and lack of structural stability in water limit their wide applications. Here, we report a facile chemical cross-linking strategy to tackle these challenges, by which the cellulose fibrils in the lamellas are covalently bridged to enhance their connectivity. The cross-linked wood sponges demonstrate high compressibility up to 70% strain and exceptional compressive fatigue resistance (∼5% plastic deformation after 10,000 cycles at 50% strain). The interfibrillar cross-linking inhibits the swelling of cellulose fibrils and preserves the arch-shaped lamellas of the sponge in water, endowing the wood sponge with excellent wet stability. Such highly elastic and wet-stable lamellar wood sponges offer a sustainable alternative to synthetic polymer-based sponges used in diverse applications.
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Affiliation(s)
- Hao Guan
- Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China
| | - Chi Zhang
- Department of Mechanical and Process Engineering, ETH Zurich, 8092 Zurich, Switzerland
| | - Kunkun Tu
- Carbon Neutrality Institute, China University of Mining and Technology, Xuzhou, Jiangsu 221008, China
- Jiangsu Key Laboratory of Coal-Based Greenhouse Gas Control and Utilization, China University of Mining and Technology, Xuzhou, Jiangsu 221008, China
| | - Xinjian Dai
- Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China
| | - Xin Wang
- Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China
| | - Xiaoqing Wang
- Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China
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3
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Senthinathan A, Tu K, Stephenson E, O'Neill B, Lipscombe L, Ji C, Butt DA, Apajee J, Train A, Crampton N. A comparison between different patient groups for diabetes management during phases of the COVID-19 pandemic: a retrospective cohort study in Ontario, Canada. BMC Prim Care 2024; 25:43. [PMID: 38280984 PMCID: PMC10821561 DOI: 10.1186/s12875-024-02272-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Accepted: 01/10/2024] [Indexed: 01/29/2024]
Abstract
BACKGROUND With the onset of the COVID-19 pandemic and the large uptake in virtual care in primary care in Canada, the care of patients with type 2 diabetes has been greatly affected. This includes decreased in-person visits, laboratory testing and in-person assessments such as blood pressure (BP). No studies have investigated if these changes persisted with pandemic progression, and it is unclear if shifts impacted patient groups uniformly. The purpose of this paper was to examine changes in diabetes care pre, early, and later pandemic across different patient groups. METHODS A repeated cross-sectional design with an open cohort was used to investigate diabetes care in adults with type 2 diabetes for a 6-month interval from March 14 to September 13 over three consecutive years: 2019 (pre-pandemic period), 2020 (early pandemic period), and 2021 (later pandemic period). Data for this study were abstracted from the University of Toronto Practice-Based Research Network (UTOPIAN) Data Safe Haven, a primary care electronic medical records database in Ontario, Canada. Changes in diabetes care, which included primary care total visits, in-person visits, hemoglobin A1c (HbA1c) testing, and BP measurements were evaluated across the phases of the pandemic. Difference in diabetes care across patient groups, including age, sex, income quintile, prior HbA1c levels, and prior BP levels, were assessed. RESULTS A total of 39,401 adults with type 2 diabetes were included in the study. Compared to the 6-month pre-pandemic period, having any in-person visits decreased significantly early pandemic (OR = 0.079 (0.076-0.082)), with a partial recovery later pandemic (OR = 0.162 (95% CI: 0.157-0.169). Compared to the pre-pandemic period, there was a significant decrease early pandemic for total visits (OR = 0.486 (95% CI: 0.470-0.503)), HbA1c testing (OR = 0.401 (95% CI: 0.389-0.413)), and BP measurement (OR = 0.121 (95% CI: 0.116-0.125)), with partial recovery later pandemic. CONCLUSIONS All measures of diabetes care were substantially decreased early pandemic, with a partial recovery later pandemic across all patient groups. With the increase in virtual care due to the COVID-19 pandemic, diabetes care has been negatively impacted over 1-year after pandemic onset.
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Affiliation(s)
- A Senthinathan
- Department of Family and Community Medicine, University of Toronto, Toronto, ON, Canada.
| | - K Tu
- Department of Family and Community Medicine, University of Toronto, Toronto, ON, Canada
- North York General Hospital, Toronto, ON, Canada
- Toronto Western Family Health Team, University Health Network, Toronto, ON, Canada
| | - E Stephenson
- Department of Family and Community Medicine, University of Toronto, Toronto, ON, Canada
| | - B O'Neill
- Department of Family and Community Medicine, University of Toronto, Toronto, ON, Canada
- Department of Family and Community Medicine, St. Michael's Hospital, Toronto, ON, Canada
- MAP Centre for Urban Health Solutions, LiKa Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
| | - L Lipscombe
- Women's College Research Institute, Women's College Hospital, Toronto, ON, Canada
- Department of Medicine, University of Toronto, Toronto, ON, Canada
| | - C Ji
- Department of Family and Community Medicine, University of Toronto, Toronto, ON, Canada
| | - D A Butt
- Department of Family and Community Medicine, University of Toronto, Toronto, ON, Canada
- Scarborough Health Network, Toronto, ON, Canada
| | - J Apajee
- Department of Family and Community Medicine, University of Toronto, Toronto, ON, Canada
| | - A Train
- Department of Family Medicine, Queen's University, Kingston, ON, Canada
| | - N Crampton
- Department of Family and Community Medicine, University of Toronto, Toronto, ON, Canada
- Toronto Western Family Health Team, University Health Network, Toronto, ON, Canada
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Ding Y, Dreimol CH, Zboray R, Tu K, Stucki S, Keplinger T, Panzarasa G, Burgert I. Passive climate regulation with transpiring wood for buildings with increased energy efficiency. Mater Horiz 2023; 10:257-267. [PMID: 36409220 PMCID: PMC9810104 DOI: 10.1039/d2mh01016j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 11/15/2022] [Indexed: 06/16/2023]
Abstract
Buildings are significant end-users of global energy. About 20% of the energy consumption worldwide is used for maintaining a comfortable indoor climate. Therefore, passive systems for indoor temperature and humidity regulation that can respond to environmental changes are very promising to reduce buildings' energy consumption. We developed a process to improve the responsiveness of wood to humidity changes by laser-drilling microscopic holes and incorporating a hygroscopic salt (calcium chloride). The resulting "transpiring wood" displays superior water adsorption capacity and high moisture exchange rate, allowing regulation of humidity and temperature by the exchange of moisture with the surrounding air. We proved that the hygrothermal performance of transpiring wood can be used to regulate indoor climate, with associated energy savings, for various climate types, thus favoring its application in the building sector. The reduction of temperature fluctuations, thanks to the buffering of temperature peaks, can lead to an indirect energy saving of about 10% for cooling and between 4-27% for heating depending on the climate. Furthermore, our transpiring wood meets different sustainability criteria, from raw materials to the fabrication process, resulting in a product with a low overall environmental impact and that is easy to recycle.
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Affiliation(s)
- Yong Ding
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093, Zürich, Switzerland.
- WoodTec Group, Cellulose & Wood Materials, Empa, 8600 Dübendorf, Switzerland
| | - Christopher H Dreimol
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093, Zürich, Switzerland.
- WoodTec Group, Cellulose & Wood Materials, Empa, 8600 Dübendorf, Switzerland
| | - Robert Zboray
- Center for X-ray Analytics, Empa, 8600 Dübendorf, Switzerland
| | - Kunkun Tu
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093, Zürich, Switzerland.
- WoodTec Group, Cellulose & Wood Materials, Empa, 8600 Dübendorf, Switzerland
| | - Sandro Stucki
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093, Zürich, Switzerland.
- WoodTec Group, Cellulose & Wood Materials, Empa, 8600 Dübendorf, Switzerland
| | - Tobias Keplinger
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093, Zürich, Switzerland.
- WoodTec Group, Cellulose & Wood Materials, Empa, 8600 Dübendorf, Switzerland
| | - Guido Panzarasa
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093, Zürich, Switzerland.
- WoodTec Group, Cellulose & Wood Materials, Empa, 8600 Dübendorf, Switzerland
| | - Ingo Burgert
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093, Zürich, Switzerland.
- WoodTec Group, Cellulose & Wood Materials, Empa, 8600 Dübendorf, Switzerland
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5
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Toufeili A, Cohen E, Ray JG, Wilton AS, Brown HK, Saunders NR, Dennis CL, Holloway AC, Morrison KM, Hanley GE, Oberlander TF, Bérard A, Tu K, Barker LC, Vigod SN. Complex chronic conditions among children born to women with schizophrenia. Schizophr Res 2022; 241:24-35. [PMID: 35074529 DOI: 10.1016/j.schres.2021.12.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 09/28/2021] [Accepted: 12/12/2021] [Indexed: 10/19/2022]
Abstract
PURPOSE Maternal schizophrenia is linked to complications in offspring near the time of birth. Whether there is also a higher future risk of the child having a complex chronic condition (CCC) - a pediatric condition affecting any bodily system expected to last at least 12 months that is severe enough to require specialty care and/or a period of hospitalization - is not known. METHODS In this population-based health administrative data cohort study (Ontario, Canada, 1995-2018), the risk for CCC was compared in 5066 children of women with schizophrenia (the exposed) vs. 2,939,320 unexposed children. Adjusted hazard ratios (aHR) were generated for occurrence of any CCC, by CCC category, and stratified by child sex, and child prematurity. RESULTS CCC was more frequent in the exposed (7.7 per 1000 person-years [268 children]) than unexposed (4.2 per 100 person-years [124,452 children]) - an aHR of 1.25 (95% CI 1.10-1.41). aHRs were notably higher in 5 of 9 CCC categories: neuromuscular (1.73, 1.28-2.33), cardiovascular (1.94, 1.64-2.29), respiratory (1.83, 1.32-2.54), hematology/immunodeficiency (2.24, 1.24-4.05) and other congenital or genetic defect (1.59, 1.16-2.17). The aHR for CCC was more pronounced among boys (1.32, 1.13-1.55) than girls (1.16, 0.96-1.40), and of similar magnitude in term (1.22, 1.05-1.42) and preterm infants (1.18, 0.95-1.46). CONCLUSIONS The risk for a CCC appears to be higher in children born to women with schizophrenia. This finding introduces opportunities for targeted preconception counselling, optimization of maternal risk factors, and intervention to support a vulnerable parent population who will experience unique challenges caring for a child with CCCs.
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Affiliation(s)
- A Toufeili
- Dept. of Psychiatry, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - E Cohen
- Dept. of Pediatrics and Edwin S.H. Leong Centre for Healthy Children, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada; Hospital for Sick Children, Toronto, Ontario, Canada; ICES, Toronto, Ontario, Canada; Institute of Health Policy, Management & Evaluation, University of Toronto, Toronto, Ontario, Canada
| | - J G Ray
- ICES, Toronto, Ontario, Canada; Institute of Health Policy, Management & Evaluation, University of Toronto, Toronto, Ontario, Canada; Department of Medicine, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada; St. Michael's Hospital, Toronto, Ontario, Canada
| | | | - H K Brown
- ICES, Toronto, Ontario, Canada; Institute of Health Policy, Management & Evaluation, University of Toronto, Toronto, Ontario, Canada; Department of Health & Society, University of Toronto Scarborough, Toronto, Ontario, Canada; Women's College Hospital and Research Institute, Toronto, Ontario, Canada
| | - N R Saunders
- Dept. of Pediatrics and Edwin S.H. Leong Centre for Healthy Children, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada; Hospital for Sick Children, Toronto, Ontario, Canada; ICES, Toronto, Ontario, Canada; Institute of Health Policy, Management & Evaluation, University of Toronto, Toronto, Ontario, Canada
| | - C L Dennis
- St. Michael's Hospital, Toronto, Ontario, Canada; Women's College Hospital and Research Institute, Toronto, Ontario, Canada; Faculty of Nursing, Toronto, Ontario, Canada
| | - A C Holloway
- Department of Obstetrics and Gynecology, Faculty of Health Sciences, McMaster University, Hamilton, Ontario, Canada
| | - K M Morrison
- Department of Pediatrics, Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada
| | - G E Hanley
- Women's College Hospital and Research Institute, Toronto, Ontario, Canada; University of British Columbia, Vancouver, British Columbia, Canada
| | - T F Oberlander
- University of British Columbia, Vancouver, British Columbia, Canada
| | - A Bérard
- Centre Hospitalier Universitaire Sainte-Justine Research Center, Montreal, Quebec, Canada; Faculty of Pharmacy, University of Montreal, Montreal, Quebec, Canada
| | - K Tu
- Institute of Health Policy, Management & Evaluation, University of Toronto, Toronto, Ontario, Canada; Department of Family and Community Medicine, University of Toronto, Toronto, Canada; North York General Hospital, Toronto, Ontario, Canada; Toronto Western Hospital Family Health Team-University Health Network, Toronto, Ontario, Canada
| | - L C Barker
- Dept. of Psychiatry, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada; Women's College Hospital and Research Institute, Toronto, Ontario, Canada
| | - S N Vigod
- Dept. of Psychiatry, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada; ICES, Toronto, Ontario, Canada; Institute of Health Policy, Management & Evaluation, University of Toronto, Toronto, Ontario, Canada; Women's College Hospital and Research Institute, Toronto, Ontario, Canada.
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6
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Tu K, Büchele S, Mitchell S, Stricker L, Liu C, Goldhahn C, Allaz J, Ding Y, Günther R, Zhang Z, Sun J, Stucki S, Panzarasa G, Zeeman SC, Burgert I, Pérez-Ramírez J, Keplinger T. Natural Wood-Based Catalytic Membrane Microreactors for Continuous Hydrogen Generation. ACS Appl Mater Interfaces 2022; 14:8417-8426. [PMID: 35107245 DOI: 10.1021/acsami.1c22850] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The development of controlled processes for continuous hydrogen generation from solid-state storage chemicals such as ammonia borane is central to integrating renewable hydrogen into a clean energy mix. However, to date, most reported platforms operate in batch mode, posing a challenge for controllable hydrogen release, catalyst reusability, and large-scale operation. To address these issues, we developed flow-through wood-based catalytic microreactors, characterized by inherent natural oriented microchannels. The prepared structured catalysts utilize silver-promoted palladium nanoparticles supported on metal-organic framework (MOF)-coated wood microreactors as the active phase. Catalytic tests demonstrate their highly controllable hydrogen production in continuous mode, and by adjusting the ammonia borane flow and wood species, we reach stable productivities of up to 10.4 cmH23 min-1 cmcat-3. The modular design of the structured catalysts proves readily scalable. Our versatile approach is applicable for other metals and MOF combinations, thus comprising a sustainable and scalable platform for catalytic dehydrogenations and applications in the energy-water nexus.
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Affiliation(s)
- Kunkun Tu
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
- WoodTec Group, Cellulose & Wood Materials, EMPA, 8600 Dübendorf, Switzerland
| | - Simon Büchele
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland
| | - Sharon Mitchell
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland
| | - Laura Stricker
- Soft Materials, Department of Materials, ETH Zürich, 8093 Zurich, Switzerland
| | - Chun Liu
- Institute of Molecular Plant Biology, Department of Biology, ETH Zürich, 8092 Zürich, Switzerland
| | - Christian Goldhahn
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
- WoodTec Group, Cellulose & Wood Materials, EMPA, 8600 Dübendorf, Switzerland
| | - Julien Allaz
- Institute of Geochemistry and Petrology, ETH Zürich, 8092 Zürich, Switzerland
| | - Yong Ding
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
- WoodTec Group, Cellulose & Wood Materials, EMPA, 8600 Dübendorf, Switzerland
| | - Roman Günther
- Laboratory of Adhesives and Polymer Materials, Institute of Materials and Process Engineering, Zürich University of Applied Sciences, 8401 Winterthur, Switzerland
- Laboratory for Multifunctional Materials, Department of Materials, ETH Zürich, 8093 Zürich, Switzerland
| | - Zhidong Zhang
- Durability of Engineering Materials, Institute for Building Materials, ETH Zürich, Stefano-Franscini-Platz 3, 8093 Zürich, Switzerland
| | - Jianguo Sun
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
- WoodTec Group, Cellulose & Wood Materials, EMPA, 8600 Dübendorf, Switzerland
| | - Sandro Stucki
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
- WoodTec Group, Cellulose & Wood Materials, EMPA, 8600 Dübendorf, Switzerland
| | - Guido Panzarasa
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
- WoodTec Group, Cellulose & Wood Materials, EMPA, 8600 Dübendorf, Switzerland
| | - Samuel C Zeeman
- Institute of Molecular Plant Biology, Department of Biology, ETH Zürich, 8092 Zürich, Switzerland
| | - Ingo Burgert
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
- WoodTec Group, Cellulose & Wood Materials, EMPA, 8600 Dübendorf, Switzerland
| | - Javier Pérez-Ramírez
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland
| | - Tobias Keplinger
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
- WoodTec Group, Cellulose & Wood Materials, EMPA, 8600 Dübendorf, Switzerland
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7
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Xiao S, Chen C, Xia Q, Liu Y, Yao Y, Chen Q, Hartsfield M, Brozena A, Tu K, Eichhorn SJ, Yao Y, Li J, Gan W, Shi SQ, Yang VW, Lo Ricco M, Zhu JY, Burgert I, Luo A, Li T, Hu L. Lightweight, strong, moldable wood via cell wall engineering as a sustainable structural material. Science 2021; 374:465-471. [PMID: 34672741 DOI: 10.1126/science.abg9556] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Shaoliang Xiao
- Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA
| | - Chaoji Chen
- Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA
| | - Qinqin Xia
- Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA
| | - Yu Liu
- Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA
| | - Yuan Yao
- Center for Industrial Ecology, Yale School of the Environment, Yale University, New Haven, CT 06511, USA
| | - Qiongyu Chen
- Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA
| | - Matt Hartsfield
- Department of Materials Science and Engineering, The Ohio State University, Columbus, OH 43210, USA
| | - Alexandra Brozena
- Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA
| | - Kunkun Tu
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland.,WoodTec Group, Cellulose & Wood Materials, Empa, 8600 Dübendorf, Switzerland
| | - Stephen J Eichhorn
- Bristol Composites Institute, CAME School of Engineering, University of Bristol, University Walk, Bristol BS8 1TR, UK
| | - Yonggang Yao
- Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA
| | - Jianguo Li
- Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA
| | - Wentao Gan
- Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA
| | - Sheldon Q Shi
- Department of Mechanical Engineering, University of North Texas, Denton, TX 76203, USA
| | - Vina W Yang
- US Department of Agriculture (USDA) Forest Products Laboratory, Madison, WI 53726, USA
| | - Marco Lo Ricco
- US Department of Agriculture (USDA) Forest Products Laboratory, Madison, WI 53726, USA
| | - J Y Zhu
- US Department of Agriculture (USDA) Forest Products Laboratory, Madison, WI 53726, USA
| | - Ingo Burgert
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland.,WoodTec Group, Cellulose & Wood Materials, Empa, 8600 Dübendorf, Switzerland
| | - Alan Luo
- Department of Materials Science and Engineering, The Ohio State University, Columbus, OH 43210, USA
| | - Teng Li
- Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA
| | - Liangbing Hu
- Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA.,Center for Materials Innovation, University of Maryland, College Park, MD 20742, USA
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8
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Shweikialrefaee B, Abdel-Qadir H, Pang A, Austin P, Singh S, Jackevicius C, Tu K, Dorian P, Lee D, Ko D. The association of stroke rate with low density lipoprotein and statin exposure in patients with atrial fibrillation (AF). Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.0472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
There are limited data on the association between cholesterol levels and stroke risk in atrial fibrillation (AF).
Objective
To quantify the association of stroke rate in AF with low-density lipoprotein (LDL) levels and statin use.
Methods
Using linked administrative databases in Ontario, Canada, we conducted a population-based retrospective cohort study of patients aged ≥66 years, diagnosed with AF between 2009–2019. We used cause-specific hazard regression to determine the association of statin use with stroke rate. We developed a second cause-specific regression model for patients with at least one lipid profile measurement in the year before AF diagnosis to study the association of LDL levels with stroke rate, while adjusting for statin use. LDL levels were modeled using restricted cubic splines (RCS). Both models were adjusted for age, sex, heart failure, hypertension, diabetes, stroke or transient ischemic attack, and vascular disease at baseline, plus anticoagulation as a time-varying covariate.
Results
We studied 261,659 qualifying patients (median age 78 years, 49% female), of whom 3,954 (1.5%) developed a stroke during one-year follow-up. A total of 142,834 (54.6%) patients were treated with statins and 145,775 (55.7%) had lipid measurements before AF diagnosis. The adjusted RCS analyses (see Figure) indicated increasing hazard ratios (HRs) for stroke with increasing low-density lipoprotein (LDL) values above 1.5mmol/L. Statin use was associated with a lower stroke rate relative to non-users (hazard ratio 0.87, 95% confidence interval 0.81–0.93, p-value <0.0001).
Conclusion
LDL levels above 1.5mmol/L were independently associated with higher stroke rates in patients with AF, while statins were associated with lower stroke rates independent of anticoagulation. This suggests that LDL measurements may improve stroke risk stratification in AF, while statins may offer an underutilized pathway to lower stroke risk in AF.
Funding Acknowledgement
Type of funding sources: Foundation. Main funding source(s): 1) Heart and stroke foundation of Canada HR for Stroke and LDL level
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Affiliation(s)
- B Shweikialrefaee
- University of Toronto, Department of Internal Medicine, Toronto, Canada
| | | | | | | | - S Singh
- Sunnybrook Health Sciences Centre, Toronto, Canada
| | | | - K Tu
- University of Toronto, Department of Family Medicine, Toronto, Canada
| | | | - D Lee
- University Health Network, Toronto, Canada
| | - D Ko
- Sunnybrook Health Sciences Centre, Toronto, Canada
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9
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Sun J, Guo H, Schädli GN, Tu K, Schär S, Schwarze FWMR, Panzarasa G, Ribera J, Burgert I. Enhanced mechanical energy conversion with selectively decayed wood. Sci Adv 2021; 7:7/11/eabd9138. [PMID: 33692104 PMCID: PMC7946366 DOI: 10.1126/sciadv.abd9138] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 11/20/2020] [Indexed: 05/02/2023]
Abstract
Producing electricity from renewable sources and reducing its consumption by buildings are necessary to meet energy and climate change challenges. Wood is an excellent "green" building material and, owing to its piezoelectric behavior, could enable direct conversion of mechanical energy into electricity. Although this phenomenon has been discovered decades ago, its exploitation as an energy source has been impaired by the ultralow piezoelectric output of native wood. Here, we demonstrate that, by enhancing the elastic compressibility of balsa wood through a facile, green, and sustainable fungal decay pretreatment, the piezoelectric output is increased over 55 times. A single cube (15 mm by 15 mm by 13.2 mm) of decayed wood is able to produce a maximum voltage of 0.87 V and a current of 13.3 nA under 45-kPa stress. This study is a fundamental step to develop next-generation self-powered green building materials for future energy supply and mitigation of climate change.
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Affiliation(s)
- Jianguo Sun
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
- WoodTec Group, Cellulose & Wood Materials, EMPA, 8600 Dübendorf, Switzerland
| | - Huizhang Guo
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
- WoodTec Group, Cellulose & Wood Materials, EMPA, 8600 Dübendorf, Switzerland
| | - Gian Nutal Schädli
- Institute for Biomechanics, Department of Health Sciences and Technology, ETH Zürich, 8093 Zürich, Switzerland
| | - Kunkun Tu
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
- WoodTec Group, Cellulose & Wood Materials, EMPA, 8600 Dübendorf, Switzerland
| | - Styfen Schär
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
| | | | - Guido Panzarasa
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
- WoodTec Group, Cellulose & Wood Materials, EMPA, 8600 Dübendorf, Switzerland
| | - Javier Ribera
- Laboratory for Cellulose & Wood Materials, EMPA, 9014 St. Gallen, Switzerland.
| | - Ingo Burgert
- Wood Materials Science, Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland.
- WoodTec Group, Cellulose & Wood Materials, EMPA, 8600 Dübendorf, Switzerland
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10
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Sun J, Guo H, Ribera J, Wu C, Tu K, Binelli M, Panzarasa G, Schwarze FWMR, Wang ZL, Burgert I. Sustainable and Biodegradable Wood Sponge Piezoelectric Nanogenerator for Sensing and Energy Harvesting Applications. ACS Nano 2020; 14:14665-14674. [PMID: 32936611 DOI: 10.1021/acsnano.0c05493] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Developing low-cost and biodegradable piezoelectric nanogenerators is of great importance for a variety of applications, from harvesting low-grade mechanical energy to wearable sensors. Many of the most widely used piezoelectric materials, including lead zirconate titanate (PZT), suffer from serious drawbacks such as complicated synthesis, poor mechanical properties (e.g., brittleness), and toxic composition, limiting their development for biomedical applications and posing environmental problems for their disposal. Here, we report a low-cost, biodegradable, biocompatible, and highly compressible piezoelectric nanogenerator based on a wood sponge obtained with a simple delignification process. Thanks to the enhanced compressibility of the wood sponge, our wood nanogenerator (15 × 15 × 14 mm3, longitudinal × radial × tangential) can generate an output voltage of up to 0.69 V, 85 times higher than that generated by native (untreated) wood, and it shows stable performance under repeated cyclic compression (≥600 cycles). Our approach suggests the importance of increased compressibility of bulk materials for improving their piezoelectric output. We demonstrate the versatility of our nanogenerator by showing its application both as a wearable movement monitoring system (made with a single wood sponge) and as a large-scale prototype with increased output (made with 30 wood sponges) able to power simple electronic devices (a LED light, a LCD screen). Moreover, we demonstrate the biodegradability of our wood sponge piezoelectric nanogenerator by studying its decomposition with cellulose-degrading fungi. Our results showcase the potential application of a wood sponge as a sustainable energy source, as a wearable device for monitoring human motions, and its contribution to environmental sustainability by electronic waste reduction.
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Affiliation(s)
- Jianguo Sun
- Wood Materials Science, Institute for Building Materials, ETH Zürich, Zürich 8093, Switzerland
- Laboratory for Cellulose & Wood Materials, Empa, Duebendorf 8600, Switzerland
| | - Hengyu Guo
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Javier Ribera
- Laboratory for Cellulose & Wood Materials, Empa, Lerchenfeldstrasse 5, St. Gallen 9014, Switzerland
| | - Changsheng Wu
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Kunkun Tu
- Wood Materials Science, Institute for Building Materials, ETH Zürich, Zürich 8093, Switzerland
- Laboratory for Cellulose & Wood Materials, Empa, Duebendorf 8600, Switzerland
| | - Marco Binelli
- Complex Materials, Department of Materials, ETH Zürich, Zürich 8093, Switzerland
| | - Guido Panzarasa
- Wood Materials Science, Institute for Building Materials, ETH Zürich, Zürich 8093, Switzerland
| | - Francis W M R Schwarze
- Laboratory for Cellulose & Wood Materials, Empa, Lerchenfeldstrasse 5, St. Gallen 9014, Switzerland
| | - Zhong Lin Wang
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Ingo Burgert
- Wood Materials Science, Institute for Building Materials, ETH Zürich, Zürich 8093, Switzerland
- Laboratory for Cellulose & Wood Materials, Empa, Duebendorf 8600, Switzerland
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11
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Fu Q, Tu K, Goldhahn C, Keplinger T, Adobes-Vidal M, Sorieul M, Burgert I. Luminescent and Hydrophobic Wood Films as Optical Lighting Materials. ACS Nano 2020; 14:13775-13783. [PMID: 32986407 DOI: 10.1021/acsnano.0c06110] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Most materials used for optical lighting applications need to produce a uniform illumination and require high mechanical and hydrophobic properties. However, they are rarely eco-friendly. Herein, a bio-based, polymer matrix-free, luminescent, and hydrophobic film with excellent mechanical properties for optical lighting purposes is demonstrated. A template is prepared by turning a wood veneer into porous scaffold from which most of the lignin and half of the hemicelluloses are removed. The infiltration of quantum dots (CdSe/ZnS) into the porous template prior to densification resulted in almost uniform luminescence (isotropic light scattering) and could be extended to various quantum dot particles, generating different light colors. In a subsequent step, the luminescent wood film is coated with hexadecyltrimethoxysilane (HDTMS) via chemical vapor deposition. The presence of the quantum dots coupled with the HDTMS coating renders the film hydrophobic (water contact angle ≈ 140°). This top-down process strongly eliminates lumen cavities and preserves the orientation of the original cellulose fibrils to create luminescent and polymer matrix-free films with high modulus and strength in the direction of fibers. The proposed optical lighting material could be attractive for interior designs (e.g., lamps and laminated cover panels), photonics, and laser devices.
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Affiliation(s)
- Qiliang Fu
- Scion, 49 Sala Street, Private Bag 3020, Rotorua 3046, New Zealand
| | - Kunkun Tu
- Wood Materials Science, ETH Zürich, 8093 Zürich, Switzerland
- Cellulose and Wood Materials, Empa-Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Christian Goldhahn
- Wood Materials Science, ETH Zürich, 8093 Zürich, Switzerland
- Cellulose and Wood Materials, Empa-Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Tobias Keplinger
- Wood Materials Science, ETH Zürich, 8093 Zürich, Switzerland
- Cellulose and Wood Materials, Empa-Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Maria Adobes-Vidal
- Wood Materials Science, ETH Zürich, 8093 Zürich, Switzerland
- Cellulose and Wood Materials, Empa-Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Mathias Sorieul
- Scion, 49 Sala Street, Private Bag 3020, Rotorua 3046, New Zealand
| | - Ingo Burgert
- Wood Materials Science, ETH Zürich, 8093 Zürich, Switzerland
- Cellulose and Wood Materials, Empa-Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
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12
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Tu K, Puértolas B, Adobes‐Vidal M, Wang Y, Sun J, Traber J, Burgert I, Pérez‐Ramírez J, Keplinger T. Green Synthesis of Hierarchical Metal-Organic Framework/Wood Functional Composites with Superior Mechanical Properties. Adv Sci (Weinh) 2020; 7:1902897. [PMID: 32274302 PMCID: PMC7141016 DOI: 10.1002/advs.201902897] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 01/20/2020] [Indexed: 05/25/2023]
Abstract
The applicability of advanced composite materials with hierarchical structure that conjugate metal-organic frameworks (MOFs) with macroporous materials is commonly limited by their inferior mechanical properties. Here, a universal green synthesis method for the in situ growth of MOF nanocrystals within wood substrates is introduced. Nucleation sites for different types of MOFs are readily created by a sodium hydroxide treatment, which is demonstrated to be broadly applicable to different wood species. The resulting MOF/wood composite exhibits hierarchical porosity with 130 times larger specific surface area compared to native wood. Assessment of the CO2 adsorption capacity demonstrates the efficient utilization of the MOF loading along with similar adsorption ability to that of pure MOF. Compression and tensile tests reveal superior mechanical properties, which surpass those obtained for polymer substrates. The functionalization strategy offers a stable, sustainable, and scalable platform for the fabrication of multifunctional MOF/wood-derived composites with potential applications in environmental- and energy-related fields.
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Affiliation(s)
- Kunkun Tu
- Wood Materials ScienceInstitute for Building MaterialsETH ZürichZürich8093Switzerland
- WoodTec GroupCellulose & Wood MaterialsEMPADübendorf8600Switzerland
| | - Begoña Puértolas
- Institute for Chemical and BioengineeringDepartment of Chemistry and Applied BiosciencesETH ZurichZurich8093Switzerland
| | - Maria Adobes‐Vidal
- Wood Materials ScienceInstitute for Building MaterialsETH ZürichZürich8093Switzerland
- WoodTec GroupCellulose & Wood MaterialsEMPADübendorf8600Switzerland
| | - Yaru Wang
- Wood Materials ScienceInstitute for Building MaterialsETH ZürichZürich8093Switzerland
- WoodTec GroupCellulose & Wood MaterialsEMPADübendorf8600Switzerland
| | - Jianguo Sun
- Wood Materials ScienceInstitute for Building MaterialsETH ZürichZürich8093Switzerland
- WoodTec GroupCellulose & Wood MaterialsEMPADübendorf8600Switzerland
| | - Jacqueline Traber
- EawagSwiss Federal Institute of Aquatic Science and TechnologyDübendorf8600Switzerland
| | - Ingo Burgert
- Wood Materials ScienceInstitute for Building MaterialsETH ZürichZürich8093Switzerland
- WoodTec GroupCellulose & Wood MaterialsEMPADübendorf8600Switzerland
| | - Javier Pérez‐Ramírez
- Institute for Chemical and BioengineeringDepartment of Chemistry and Applied BiosciencesETH ZurichZurich8093Switzerland
| | - Tobias Keplinger
- Wood Materials ScienceInstitute for Building MaterialsETH ZürichZürich8093Switzerland
- WoodTec GroupCellulose & Wood MaterialsEMPADübendorf8600Switzerland
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13
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Kassardjian CD, Widdifield J, Paterson JM, Kopp A, Nagamuthu C, Barnett C, Tu K, Breiner A. Serious infections in patients with myasthenia gravis: population‐based cohort study. Eur J Neurol 2020; 27:702-708. [DOI: 10.1111/ene.14153] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 01/09/2020] [Indexed: 11/29/2022]
Affiliation(s)
- C. D. Kassardjian
- Division of Neurology Department of Medicine St Michael's Hospital University of Toronto Toronto ON
| | - J. Widdifield
- Holland Bone & Joint Research Program Sunnybrook Health Sciences Centre Sunnybrook Research Institute Toronto ON
- Institute of Health Policy, Management & Evaluation University of Toronto Toronto ON
- ICES Toronto ON
| | - J. M. Paterson
- Institute of Health Policy, Management & Evaluation University of Toronto Toronto ON
- ICES Toronto ON
| | | | | | - C. Barnett
- Division of Neurology Department of Medicine Ellen and Martin Prosserman Centre for Neuromuscular Diseases University Health Network University of Toronto Toronto ON
| | - K. Tu
- Department of Community and Family Medicine North York General Hospital University Health Network Toronto ON
| | - A. Breiner
- Division of Neurology Department of Medicine The Ottawa Hospital and Ottawa Hospital Research Institute Ottawa ON Canada
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14
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Hoang-Kim A, Parpia C, Freitas C, Austin PC, Ross HJ, Wijeysundera HC, Tu K, Mak S, Farkouh ME, Schull M, Rochon P, Mason R, Lee DS. P3518Men with heart failure have higher readmission rates: a closer review of sex and gender based analyses. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz745.0382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
There has been increased attention on reducing hospital readmission rates. However, little is known about any difference in readmission rates in heart failure by sex, although evidence exists demonstrating differences in the etiology of heart failure. As a result, strategies to optimize readmission reduction programs and care strategies for women and men remain unclear.
Purpose
(1) To identify studies examining readmission rates according to sex, and (2) to provide a qualitative overview of possible considerations for the impact of sex or gender.
Methods
A scoping protocol was developed using the Arksey and O'Malley framework and the Joanna Briggs Institute methodology. Our search strategy was reviewed according to the peer-review of electronic search strategy (PRESS) checklist. Full text articles published between 2002 and 2017 and drawn from multiple databases (i.e. MEDLINE, EMBASE), grey literature (i.e. National Technical Information, Duck Duck Go), and experts were consulted for additional articles. Screening criteria were established a priori. Once an acceptable inter-rater agreement was established at 80% by two independent reviewers, articles were screened for potential eligibility. A descriptive analytical method was employed to chart primary research articles. Articles were considered relevant if the cohort consisted of adult heart failure patients who were readmitted after an index hospitalization and a sex/gender-based analysis was performed.
Results
The literature search yielded 5887 articles, of which 746 underwent full text assessment for eligibility. Of 164 eligible articles, 34 studies addressed the primary outcome, 103 studies considered sex differences as a secondary outcome and 25 studies included disaggregated data for sex but no subsequent interaction was reported. Good inter-rater agreement was reached: 83% for title and abstract screening; 88% for full text review; kappa: 0.69 (95% CI: 0.526–0.851). Twelve of 34 studies included for the primary outcome reported higher readmission rates for men compared to five studies reporting higher readmission rates for women. However, there were differential readmission rates that were dependent on duration of follow-up. Women were more likely to experience higher readmission rates than men when time to event was less than one year. Readmission rates for men were higher when follow-up was longer than one year.
Conclusion
Sex differences in readmission rates were dependent on follow up time. Most studies used composite outcomes and had short times to event, which may mask underlying effects of sex on readmission.
Acknowledgement/Funding
Ontario SPOR Support Unit
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Affiliation(s)
| | - C Parpia
- Women's College Hospital, Toronto, Canada
| | - C Freitas
- University Health Network, Toronto, Canada
| | | | - H J Ross
- University Health Network, Toronto, Canada
| | | | - K Tu
- University Health Network, Toronto, Canada
| | - S Mak
- Mount Sinai Hospital of the University Health Network, Toronto, Canada
| | | | | | - P Rochon
- Women's College Hospital, Toronto, Canada
| | - R Mason
- Women's College Hospital, Toronto, Canada
| | - D S Lee
- University Health Network, Toronto, Canada
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15
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Zhou D, Wang Z, Tu S, Chen S, Peng J, Tu K. Effects of cold plasma, UV‐C or aqueous ozone treatment on
Botrytis cinerea
and their potential application in preserving blueberry. J Appl Microbiol 2019; 127:175-185. [DOI: 10.1111/jam.14280] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 03/18/2019] [Accepted: 04/04/2019] [Indexed: 12/28/2022]
Affiliation(s)
- D. Zhou
- College of Food Science and Technology Nanjing Agricultural University Nanjing China
| | - Z. Wang
- College of Food Science and Technology Nanjing Agricultural University Nanjing China
| | - S. Tu
- Medical Sciences Division University of Oxford Oxford UK
- Sydney Medical School The University of Sydney Sydney NSW Australia
| | - S. Chen
- College of Food Science and Technology Nanjing Agricultural University Nanjing China
| | - J. Peng
- College of Food Science and Technology Nanjing Agricultural University Nanjing China
| | - K. Tu
- College of Food Science and Technology Nanjing Agricultural University Nanjing China
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16
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Frey M, Biffi G, Adobes‐Vidal M, Zirkelbach M, Wang Y, Tu K, Hirt AM, Masania K, Burgert I, Keplinger T. Tunable Wood by Reversible Interlocking and Bioinspired Mechanical Gradients. Adv Sci (Weinh) 2019; 6:1802190. [PMID: 31131194 PMCID: PMC6524091 DOI: 10.1002/advs.201802190] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 02/25/2019] [Indexed: 05/24/2023]
Abstract
Elegant design principles in biological materials such as stiffness gradients or sophisticated interfaces provide ingenious solutions for an efficient improvement of their mechanical properties. When materials such as wood are directly used in high-performance applications, it is not possible to entirely profit from these optimizations because stiffness alterations and fiber alignment of the natural material are not designed for the desired application. In this work, wood is turned into a versatile engineering material by incorporating mechanical gradients and by locally adapting the fiber alignment, using a shaping mechanism enabled by reversible interlocks between wood cells. Delignification of the renewable resource wood, a subsequent topographic stacking of the cellulosic scaffolds, and a final densification allow fabrication of desired 3D shapes with tunable fiber architecture. Additionally, prior functionalization of the cellulose scaffolds allows for obtaining tunable functionality combined with mechanical gradients. Locally controllable elastic moduli between 5 and 35 GPa are obtained, inspired by the ability of trees to tailor their macro- and micro-structure. The versatility of this approach has significant relevance in the emerging field of high-performance materials from renewable resources.
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Affiliation(s)
- Marion Frey
- Wood Materials ScienceDepartment of Civil, Environmental and Geomatic EngineeringETH Zürich8093ZürichSwitzerland
- Cellulose & Wood MaterialsFunctional MaterialsEMPA8600DübendorfSwitzerland
| | - Giulia Biffi
- Wood Materials ScienceDepartment of Civil, Environmental and Geomatic EngineeringETH Zürich8093ZürichSwitzerland
| | - Maria Adobes‐Vidal
- Wood Materials ScienceDepartment of Civil, Environmental and Geomatic EngineeringETH Zürich8093ZürichSwitzerland
- Cellulose & Wood MaterialsFunctional MaterialsEMPA8600DübendorfSwitzerland
| | - Meri Zirkelbach
- Wood Materials ScienceDepartment of Civil, Environmental and Geomatic EngineeringETH Zürich8093ZürichSwitzerland
- Design and ArtsLucerne University of Applied Sciences and Arts6020EmmenSwitzerland
| | - Yaru Wang
- Wood Materials ScienceDepartment of Civil, Environmental and Geomatic EngineeringETH Zürich8093ZürichSwitzerland
- Cellulose & Wood MaterialsFunctional MaterialsEMPA8600DübendorfSwitzerland
| | - Kunkun Tu
- Wood Materials ScienceDepartment of Civil, Environmental and Geomatic EngineeringETH Zürich8093ZürichSwitzerland
- Cellulose & Wood MaterialsFunctional MaterialsEMPA8600DübendorfSwitzerland
| | - Ann M. Hirt
- Institute for GeophysicsDepartment of Earth SciencesETH Zürich8093ZürichSwitzerland
| | - Kunal Masania
- Complex MaterialsDepartment of MaterialsETH Zürich8093ZürichSwitzerland
| | - Ingo Burgert
- Wood Materials ScienceDepartment of Civil, Environmental and Geomatic EngineeringETH Zürich8093ZürichSwitzerland
- Cellulose & Wood MaterialsFunctional MaterialsEMPA8600DübendorfSwitzerland
| | - Tobias Keplinger
- Wood Materials ScienceDepartment of Civil, Environmental and Geomatic EngineeringETH Zürich8093ZürichSwitzerland
- Cellulose & Wood MaterialsFunctional MaterialsEMPA8600DübendorfSwitzerland
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17
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Donio P, Freitas C, Austin P, Ross H, Abdel-Qadir H, Wijeysundera H, Tu K, Cram P, Liu P, Abrams H, Udell J, Mak S, Farkouh M, Tu J, Wang X, Tobe S, Lee D. COMPARISON OF READMISSION AND DEATH AMONG CARDIAC PATIENTS IN NORTHERN VS. SOUTHERN ONTARIO. Can J Cardiol 2018. [DOI: 10.1016/j.cjca.2018.07.357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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18
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Sun L, Wang Y, Li Q, Wang L, Wang C, Yao B, Liu Z, Song T, Tu K, Liu Q. Hepatic stellate cells (HSCs) activating HSF1-mediated COMP secretion promote liver metastasis of pancreatic cancer through CD36/AKT/FOXM1 signaling. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy151.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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19
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Zhou D, Wang Z, Li M, Xing M, Xian T, Tu K. Carvacrol and eugenol effectively inhibitRhizopus stoloniferand control postharvest soft rot decay in peaches. J Appl Microbiol 2017; 124:166-178. [DOI: 10.1111/jam.13612] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 09/16/2017] [Accepted: 10/09/2017] [Indexed: 11/28/2022]
Affiliation(s)
- D. Zhou
- College of Food Science and Technology; Nanjing Agricultural University; Nanjing China
| | - Z. Wang
- College of Food Science and Technology; Nanjing Agricultural University; Nanjing China
| | - M. Li
- College of Food Science and Technology; Nanjing Agricultural University; Nanjing China
| | - M. Xing
- College of Food Science and Technology; Nanjing Agricultural University; Nanjing China
| | - T. Xian
- College of Food Science and Technology; Nanjing Agricultural University; Nanjing China
| | - K. Tu
- College of Food Science and Technology; Nanjing Agricultural University; Nanjing China
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20
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Tobias DJ, Tu K, Klein ML. Assessment of all-atom potentials for modeling membranes: molecular dynamics simulations of solid and liquid alkanes and crystals of phospholipid fragments. ACTA ACUST UNITED AC 2017. [DOI: 10.1051/jcp/1997941482] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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21
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Tu K, Wang X, Kong L, Chang H, Liu J. Fabrication of robust, damage-tolerant superhydrophobic coatings on naturally micro-grooved wood surfaces. RSC Adv 2016. [DOI: 10.1039/c5ra24407b] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Damage-tolerant superhydrophobic wood surfaces were fabricated by applying an epoxy-resin primer coating and subsequent construction of silica/epoxy-resin/fluorinated alkylsilane composite films.
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Affiliation(s)
- Kunkun Tu
- Research Institute of Wood Industry
- Chinese Academy of Forestry
- Beijing 100091
- China
| | - Xiaoqing Wang
- Research Institute of Wood Industry
- Chinese Academy of Forestry
- Beijing 100091
- China
| | - Lizhuo Kong
- Research Institute of Wood Industry
- Chinese Academy of Forestry
- Beijing 100091
- China
| | - Huanjun Chang
- Research Institute of Wood Industry
- Chinese Academy of Forestry
- Beijing 100091
- China
| | - Junliang Liu
- Research Institute of Wood Industry
- Chinese Academy of Forestry
- Beijing 100091
- China
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22
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Tu K, Waldron K, Ingham L, De Barsy T, De Baerdemaeker J. Effect of picking time and storage conditions on ‘Cox’s Orange Pippin’ apple texture in relation to cell wall changes. ACTA ACUST UNITED AC 2015. [DOI: 10.1080/14620316.1997.11515589] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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23
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Chang H, Tu K, Wang X, Liu J. Fabrication of mechanically durable superhydrophobic wood surfaces using polydimethylsiloxane and silica nanoparticles. RSC Adv 2015. [DOI: 10.1039/c5ra03070f] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Mechanically durable superhydrophobic coatings were fabricated on the intrinsically heterogeneous wood substrate using polydimethylsiloxane (PDMS) and silica nanoparticles.
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Affiliation(s)
- Huanjun Chang
- Research Institute of Wood Industry
- Chinese Academy of Forestry
- Beijing 100091
- P. R. China
| | - Kunkun Tu
- Research Institute of Wood Industry
- Chinese Academy of Forestry
- Beijing 100091
- P. R. China
| | - Xiaoqing Wang
- Research Institute of Wood Industry
- Chinese Academy of Forestry
- Beijing 100091
- P. R. China
| | - Junliang Liu
- Research Institute of Wood Industry
- Chinese Academy of Forestry
- Beijing 100091
- P. R. China
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Widdifield J, Young J, Bombardier C, Jaakkimainen R, Butt D, Ivers N, Bernatsky S, Paterson J, Thorne J, Ahluwalia V, Tomlinson G, Tu K. FRI0194 Identifying Patients with Rheumatoid Arthritis in Primary Care Electronic Medical Records. Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2014-eular.4816] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Birken C, Tu K, Oud W, Carsley S, Hanna M, Lebovic G, Guttmann A. 166: Using Electronic Medical Records to Estimate Overweight and Obesity Rates in Children in Ontario, Canada. Paediatr Child Health 2014. [DOI: 10.1093/pch/19.6.e35-162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Allin S, Munce S, Carlin L, Butt D, Tu K, Hawker G, Sale J, Jaglal S. Fracture risk assessment after BMD examination: whose job is it, anyway? Osteoporos Int 2014; 25:1445-53. [PMID: 24610580 PMCID: PMC3988517 DOI: 10.1007/s00198-014-2661-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 02/16/2014] [Indexed: 11/05/2022]
Abstract
UNLABELLED Fracture risk assessments on bone mineral density reports guide family physicians' treatment decisions but are subject to inaccuracy. Qualitative analysis of interviews with 22 family physicians illustrates their pervasive questioning of reported assessment accuracy and independent assumption of responsibility for assessment. Assumption of responsibility is common despite duplicating specialists' work. INTRODUCTION Fracture risk is the basis for recommendations of treatment for osteoporosis, but assessments on bone mineral density (BMD) reports are subject to known inaccuracies. This creates a complex situation for referring physicians, who must rely on assessments to inform treatment decisions. This study was designed to broadly understand physicians' current experiences with and preferences for BMD reporting; the present analysis focuses on their interpretation and use of the fracture risk assessments on reports, specifically METHODS A qualitative, thematic analysis of one-on-one interviews with 22 family physicians in Ontario, Canada was performed. RESULTS The first major theme identified in interview data reflects questioning by family physicians of reported fracture risk assessments' accuracy. Several major subthemes related to this included questioning of: 1) accuracy in raw bone mineral density measures (e.g., g/cm(2)); 2) accurate inclusion of modifying risk factors; and 3) the fracture risk assessment methodology employed. A second major theme identified was family physicians' independent assumption of responsibility for risk assessment and its interpretation. Many participants reported that they computed risk assessments in their practice to ensure accuracy, even when provided with assessments on reports. CONCLUSIONS Results indicate family physicians question accuracy of risk assessments on BMD reports and often assume responsibility both for revising and relating assessments to treatment recommendations. This assumption of responsibility is common despite the fact that it may duplicate the efforts of reading physicians. Better capture of risk information on BMD referrals, quality control standards for images and standardization of risk reporting may help attenuate some inefficiency.
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Affiliation(s)
- S Allin
- Department of Physical Therapy, University of Toronto, 160-500 University Ave., M5G 1V7, Toronto, Ontario, Canada,
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Butt DA, Mamdani M, Austin PC, Tu K, Gomes T, Glazier RH. The risk of falls on initiation of antihypertensive drugs in the elderly. Osteoporos Int 2013; 24:2649-57. [PMID: 23612794 DOI: 10.1007/s00198-013-2369-7] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 04/05/2013] [Indexed: 02/06/2023]
Abstract
SUMMARY Antihypertensive drugs are associated with an immediate increased falls risk in elderly patients which was significant during the first 14 days after receiving a thiazide diuretic, angiotensin-converting enzyme inhibitor, angiotensin II receptor blocker, calcium channel blocker, or beta-adrenergic blocker. Fall prevention strategies during this period may prevent fall-related injuries. INTRODUCTION The purpose of this study is to evaluate if initiation of the common antihypertensive drugs is associated with the occurrence of falls. METHODS This population-based self-controlled case series study used healthcare administrative databases to identify new users of antihypertensive drugs in the elderly aged 66 and older living in Ontario, Canada who suffered a fall from April 1, 2000 to March 31, 2009. The risk period was the first 45 days following antihypertensive therapy initiation, further subdivided into 0-14 and 15-44 days with control periods before and after treatment in a 450-day observation period. We calculated the relative incidence (incidence rate ratio, IRR), defined as the rate of falls in the risk period compared to falls rate in the control periods. RESULTS Of the 543,572 new users of antihypertensive drugs among community-dwelling elderly, 8,893 experienced an injurious fall that required hospital care during the observation period. New users had a 69 % increased risk of having an injurious fall during the first 45 days following antihypertensive treatment (IRR = 1.69; 95 % CI, 1.57-1.81). This finding was consistent for thiazide diuretics, angiotensin-converting enzyme inhibitors, calcium channel blockers, and beta-adrenergic blockers but not angiotensin II receptor antagonists. There was also an increased falls risk during the first 14 days of antihypertensive drug initiation (IRR = 1.94; 95 % CI, 1.75-2.16), which was consistent for all antihypertensive drug classes. CONCLUSIONS This study suggests that initiation of antihypertensive drugs is a risk factor for falls in the elderly. Fall prevention strategies during this period may reduce injuries.
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Affiliation(s)
- D A Butt
- Department of Family and Community Medicine, The Scarborough Hospital, University of Toronto, Toronto, Ontario, Canada,
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Widdifield J, Paterson JM, Bernatsky S, Tu K, Thorne JC, Bombardier C. FRI0518 Epidemiology of rheumatoid arthritis in a universal public health care system: results from the ontario ra administrative database (ORAD). Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2013-eular.1645] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Schultz SE, Rothwell DM, Chen Z, Tu K. Identifying cases of congestive heart failure from administrative data: a validation study using primary care patient records. Chronic Dis Inj Can 2013; 33:160-166. [PMID: 23735455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
INTRODUCTION To determine if using a combination of hospital administrative data and ambulatory care physician billings can accurately identify patients with congestive heart failure (CHF), we tested 9 algorithms for identifying individuals with CHF from administrative data. METHODS The validation cohort against which the 9 algorithms were tested combined data from a random sample of adult patients from EMRALD, an electronic medical record database of primary care physicians in Ontario, Canada, and data collected in 2004/05 from a random sample of primary care patients for a study of hypertension. Algorithms were evaluated on sensitivity, specificity, positive predictive value, area under the curve on the ROC graph and the combination of likelihood ratio positive and negative. RESULTS We found that that one hospital record or one physician billing followed by a second record from either source within one year had the best result, with a sensitivity of 84.8% and a specificity of 97.0%. CONCLUSION Population prevalence of CHF can be accurately measured using combined administrative data from hospitalization and ambulatory care.
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Affiliation(s)
- S E Schultz
- Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.
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Widdifield J, Bernatsky S, Paterson J, Thorne J, Tu K, Bombardier C. FRI0410 Rheumatoid arthritis (RA) care: Geographic disparities and impact of primary care physicians on access to rheumatologists. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2012-eular.2867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Jiménez C, Prigent C, Mueller B, Seneviratne SI, McCabe MF, Wood EF, Rossow WB, Balsamo G, Betts AK, Dirmeyer PA, Fisher JB, Jung M, Kanamitsu M, Reichle RH, Reichstein M, Rodell M, Sheffield J, Tu K, Wang K. Global intercomparison of 12 land surface heat flux estimates. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010jd014545] [Citation(s) in RCA: 275] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Tu K, Mitiku T, Guo H, Lee DS, Tu JV. Myocardial infarction and the validation of physician billing and hospitalization data using electronic medical records. Chronic Dis Can 2010; 30:141-146. [PMID: 20946715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
OBJECTIVE Population-based identification of patients with a myocardial infarction is limited to patients presenting to hospital with an acute event. We set out to determine if adding physician billing data to hospital discharge data would result in an accurate capture of patients who have had a myocardial infarction. METHODS We performed a retrospective chart abstraction of 969 randomly selected adult patients using data abstracted from primary care physicians on an electronic medical record in Ontario, Canada, as the reference standard. RESULTS An algorithm of 3 physician billings in a one-year period with at least one being by a specialist or within a hospital or emergency room plus one hospital discharge abstract performed with a sensitivity of 80.4% (95% CI: 69.5-91.3), specificity of 98.0% (95% CI: 97.1-98.9), positive predictive value of 69.5% (95% CI: 57.7-81.2), negative predictive value of 98.9% (95% CI: 98.2% to 99.6%) and kappa statistic of 0.73 (95% CI: 0.63-0.83). CONCLUSION Using a combination of hospital discharge abstracts and physician billing data may be the best way of assessing trends of MI occurrence over time since it increases the capture of MI beyond those patients who have been hospitalized.
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Affiliation(s)
- K Tu
- Institute for Clinical Evaluative Sciences (ICES), Toronto, Canada.
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Kaczorowski J, Chambers LW, Dolovich L, Farrell B, McDonough B, Sebaldt R, Lehana T, Tu K, Zagorski B, Goeree R, Paterson JM, Levitt C, Hogg W, Karwalajtys T, Gierman T, Laryea S, Carter M, Cross D. IMPROVING CARDIOVASCULAR HEALTH AT THE POPULATION LEVEL: A 39 COMMUNITY CLUSTER-RANDOMISED TRIAL OF THE CARDIOVASCULAR HEALTH AWARENESS PROGRAM (CHAP): PS.3.03. J Hypertens 2010. [DOI: 10.1097/01.hjh.0000384008.86281.66] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Tu K, Gochin M. Structure determination by restrained molecular dynamics using NMR pseudocontact shifts as experimentally determined constraints. J Am Chem Soc 2009; 121:9276-85. [PMID: 17917690 DOI: 10.1021/ja9904540] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The structure of a DNA octamer d(TTGGCCAA)(2) complexed to chromomycin-A(3) and a single divalent cobalt ion has been solved by using the pseudocontact shifts due to the unpaired electrons on the cobalt. A protocol was developed and critically evaluated for using the pseudocontact shifts in structure determination. The pseudocontact shifts were input as experimental restraints in molecular dynamics simulations with or without NOE constraints. Both the magnitude and orientation of the susceptibility anisotropy tensor required for the shift calculations were determined during the simulations by iterative refinement. The pseudocontact shifts could be used to define the structure to a very high precision and accuracy compared with a corresponding NOE-determined structure. Convergence was obtained from different starting structures and tensors. A structure determination using both NOE's and pseudocontact shifts revealed a general agreement between the two data sets. However, some evidence for a discrepancy between NOE's and pseudocontact shifts was observed in the backbone and terminal base pairs of the DNA. Violations in shift or NOE restraints remaining in the final structures were examined and may be a reflection of motional averaging of the constraints and evidence for flexibility. This work demonstrates that pseudocontact shifts are a powerful tool for NMR structure determination.
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Affiliation(s)
- K Tu
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94143, USA
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Abstract
Beta-blockers are less beneficial than other antihypertensive drugs in the elderly with hypertension. All elderly patients in Ontario, Canada (population over 3.5 million elderly) without co-morbidities who were first treated for hypertension with a beta-blocker were studied in a retrospective population-based cohort study (1994-2002) to determine the characteristics of those prescribed beta-blockers. Of the 194,761 patients in our cohort, 25 485 (13%) were prescribed a beta-blocker as their first antihypertensive agent. On multivariate analysis, factors significantly associated with being prescribed a beta-blocker as first-line therapy included male sex (adjusted odds ratio (OR) 1.06 [95% CI 1.03-1.09] vs women), younger age (adjusted OR 1.67 [95% CI 1.55-1.79] for patients aged 66-69 vs those aged 85 or older), residence in a long-term care facility (adjusted OR 1.19 [95% CI 1.04-1.35] vs living in the community) and lower socioeconomic status (adjusted OR 1.07 [95% CI 1.02-1.12], for lowest quintile vs highest quintile). Patients with diabetes were substantially less likely to be prescribed beta-blockers (adjusted OR 0.42 [95% CI 0.40-0.44]). Greater efforts are required to educate physicians to select other drugs for initial therapy in older patients with uncomplicated hypertension.
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Affiliation(s)
- K Tu
- Institute for Clinical Evaluative Sciences, Toronto, Canada
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Abstract
OBJECTIVES The extensive use of benzodiazepines has been a concern of healthcare providers and policy makers in Canada and around the world. The purpose of this study was to examine temporal trends in benzodiazepine prescriptions dispensed in older people from 1993-1998. DESIGN Retrospective population-based cross-sectional study using administrative databases. SETTING Ontario, Canada. PARTICIPANTS The over 1 million residents of Ontario age 65 and older covered by the provincial universal drug benefit program. MEASUREMENTS The main outcome measures were the prevalence, overall and with respect to age and gender, of benzodiazepine prescriptions dispensed and the ratio of the number of people to whom short- versus long-acting benzodiazepine prescriptions were dispensed in each study year. The annual rates of switching to other psychotropic agents were examined for those patients that discontinued filling benzodiazepine prescriptions. RESULTS The annual prevalence of benzodiazepine prescriptions dispensed decreased consistently over time (25.1% in 1993 to 22.5% in 1998; P < .001). Benzodiazepine dispensing prevalence increased with increasing age (approximately 20% of those age 65 to 69 to approximately 30% of those age > or =85; P < .001) and more females than males received the medication (relative risk = 1.50, 95% confidence interval = 1.49-1.51). The ratio of short- to long-acting benzodiazepine prescriptions filled increased over time (3.6 in 1993 to 5.8 in 1998; P < .001), in line with guideline recommendations. Rates of switching to antidepressants increased over time (8.5% in 1993 to 10.2% in 1998; P < .001), whereas switching to barbiturates was consistently low (0.12%; P = .403). CONCLUSION The prevalence of benzodiazepine therapy for older people in Ontario has steadily declined between 1993 and 1998. There is a trend of dispensing relatively more short-acting than long-acting benzodiazepines and of replacing benzodiazepines with antidepressants in older people without a remarkable increase in barbiturate consumption. These findings suggest that, without undue regulation, physicians are making progress in the prescribing of benzodiazepine therapy on the basis of current knowledge available.
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Affiliation(s)
- K Tu
- Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada
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Mamdani MM, Tu K, Jaakkimainen L, Bica A, Hux J. Proton pump inhibitors. Compliance with a mandated step-up program. Can Fam Physician 2001; 47:531-5. [PMID: 11281086 PMCID: PMC2018396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
OBJECTIVE To assess compliance with a step-up approach to proton pump inhibitor (PPI) therapy before implementation of a new provincial policy to promote histamine-type 2 receptor antagonist (H2RA) use before PPI therapy. DESIGN Population-based, retrospective, open cohort study using prescribing and medical procedure data from January 1, 1995, to April 30, 1999. SETTING Health administration databases for the universal health care system in Ontario. PARTICIPANTS Approximately 1.4 million residents of Ontario older than 65 years. MAIN OUTCOME MEASURES Proportion of patients who received a trial of H2RA therapy or gastrointestinal diagnostic testing 12 months before starting PPI therapy in 1996. RESULTS Among the 25,870 patients who met study criteria in 1996, about 63% had received H2RAs 12 months before starting PPI therapy and 73% had had a trial of H2RAs or gastrointestinal diagnostic testing. Repeat analysis for January through April 1999, following the new policy implementation, showed that about 72% of patients had had a trial of H2RAs within 12 months of starting PPI therapy. CONCLUSION A modest gain (9%) in compliance with using H2RA therapy within 12 months before starting PPI therapy was seen following introduction of the step-up intervention. In future, costs and benefits of potential interventions should be carefully considered before implementing new policies.
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Affiliation(s)
- M M Mamdani
- Institute for Clinical Evaluative Sciences, Toronto, Ont
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Mamdani MM, Tu K, van Walraven C, Austin PC, Naylor CD. Postmenopausal estrogen replacement therapy and increased rates of cholecystectomy and appendectomy. CMAJ 2000; 162:1421-4. [PMID: 10834045 PMCID: PMC1232454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
BACKGROUND Several studies have indicated that estrogen may prime inflammatory and nociceptive pathways, leading to symptoms that mimic cholecystitis. We set out to confirm the relation between recent estrogen use and cholecystectomy in postmenopausal women and to test the novel hypothesis that a similar relation exists for appendectomy. METHODS We developed a retrospective cohort using prescribing and surgical procedure information from health administrative databases for approximately 800,000 female residents of Ontario who were over 65 years of age between July 1, 1993, and Mar. 31, 1998. We compared the incidence of cholecystectomy and appendectomy among women recently prescribed estrogen replacement therapy, levothyroxine and dihydropyridine calcium-channel antagonists (DCCA) using age-adjusted Cox proportional hazards models. Patients were followed for a mean of 540 (standard deviation [SD] 449) days. RESULTS Compared with women taking DCCA, those who had recently begun taking estrogen were significantly more likely to undergo cholecystectomy (age-adjusted risk ratio [aRR] 1.9, 95% confidence interval [CI] 1.6-2.2) and appendectomy (aRR 1.8, 95% CI 1.1-3.0). No significant difference in either outcome measure was found between the levothyroxine users and the DCCA users. INTERPRETATION This study identifies an increased risk of cholecystectomy and appendectomy among postmenopausal women who have recently begun estrogen replacement therapy.
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Affiliation(s)
- M M Mamdani
- Institute for Clinical Evaluative Sciences, Toronto, Ont
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Abstract
Molecular dynamics simulations have been used to investigate the structure of hybrid bilayers (HB) formed by dipalmitoylphosphatidylcholine (DPPC) lipid monolayers adsorbed on a hydrophobic alkanethiol self-assembled monolayer (SAM). The HB system was studied at 20 degrees C and 60 degrees C, and the results were compared with recent neutron reflectivity measurements (Meuse, C. W., S. Krueger, C. F. Majkrzak, J. A. Dura, J. Fu, J. T. Connor, and A. L. Plant. 1998. Biophys. J. 74:1388) and previous simulations of hydrated multilamellar bilayers (MLB) of DPPC (Tu, K., D. J. Tobias, and M. L. Klein. 1995. Biophys. J. 69:2558; and 1996. 70:595). The overall structures of the HBs are in very good agreement with experiment. The structure of the SAM monolayer is hardly perturbed by the presence of the DPPC overlayer. The DPPC layer presents characteristics very similar to the MLB gel phase at low temperature and to the liquid crystal phase at high temperature. Subtle changes have been found for the lipid/water interface of the HBs compared to the MLBs. The average phosphatidylcholine headgroup orientation is less disordered, and this produces changes in the electric properties of the HB lipid/water interface. These changes are attributed to the fact that the aqueous environment of the lipids in these unilamellar films is different from that of MLB stacks. Finally, examination of the intramolecular and whole-molecule dynamics of the DPPC molecules in the fluid phase HB and MLB membranes revealed that the reorientations of the upper part of the acyl chains (near the acyl ester linkage) are slower, the single molecule protrusions are slightly damped, and the lateral rattling motions are significantly reduced in the HB compared with the MLB.
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Affiliation(s)
- M Tarek
- Laboratory for Research on the Structure of Matter, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6202, USA
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Abstract
The conventional formula for relating CD2 average order parameters <Sn> to average methylenic travel <Dn> is flawed when compared to molecular dynamics simulations of dipalmitoylphosphatidylcholine. Inspired by the simulated probability distribution functions, a new formula is derived that satisfactorily relates these quantities. This formula is used to obtain the average chain length <LC>, and the result agrees with the direct simulation result for <LC>. The simulation also yields a hydrocarbon thickness 2<DC>. The result <LC> = <DC> is consistent with a model of chain packing with both early chain termination and partial interdigitation of chains from opposing monolayers. The actual simulated area per lipid <A> is easily obtained from the order parameters. However, when this method is applied to NMR order parameter data from dimyristoylphosphatidylcholine, the resulting <A> is 10% larger than the currently accepted value.
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Affiliation(s)
- H I Petrache
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
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Abstract
We report a 1.4-ns constant-pressure molecular dynamics simulation of cholesterol at 12.5 mol% in a dipalmitoylphosphatidylcholine (DPPC) bilayer at 50 degrees C and compare the results to our previous simulation of a pure DPPC bilayer. The interlamellar spacing was increased by 2.5 A in the cholesterol-containing bilayer, consistent with x-ray diffraction results, whereas the bilayer thickness was increased by only 1 A. The bilayer/water interface was more abrupt because the lipid headgroups lie flatter to fill spaces left by the cholesterol molecules. This leads to less compensation by the lipid headgroups of the oriented water contribution to the membrane dipole potential and could explain the experimentally observed increase in the magnitude of the dipole potential by cholesterol. Our calculations suggested that 12.5 mol% cholesterol does not significantly affect the conformations and packing of the hydrocarbon chains and produces only a slight reduction in the empty free volume. However, cholesterol has a significant influence on the subnanosecond time scale lipid dynamics: the diffusion constant for the center-of-mass "rattling" motion was reduced by a factor of 3, and the reorientational motion of the methylene groups was slowed along the entire length of the hydrocarbon chains.
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Affiliation(s)
- K Tu
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94143-0446, USA
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Tu K, Tarek M, Klein ML, Scharf D. Effects of anesthetics on the structure of a phospholipid bilayer: molecular dynamics investigation of halothane in the hydrated liquid crystal phase of dipalmitoylphosphatidylcholine. Biophys J 1998; 75:2123-34. [PMID: 9788906 PMCID: PMC1299885 DOI: 10.1016/s0006-3495(98)77655-6] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We report the results of constant temperature and pressure molecular dynamics calculations carried out on the liquid crystal (Lalpha) phase of dipalmitoylphosphatidylcholine with a mole fraction of 6.5% halothane (2-3 MAC). The present results are compared with previous simulations for pure dipalmitoylphosphatidylcholine under the same conditions (Tu et al., 1995. Biophys. J. 69:2558-2562) and with various experimental data. We have found subtle structural changes in the lipid bilayer in the presence of the anesthetic compared with the pure lipid bilayer: a small lateral expansion is accompanied by a modest contraction in the bilayer thickness. However, the overall increase in the system volume is found to be comparable to the molecular volume of the added anesthetic molecules. No significant change in the hydrocarbon chain conformations is apparent. The observed structural changes are in fair agreement with NMR data corresponding to low anesthetic concentrations. We have found that halothane exhibits no specific binding to the lipid headgroup or to the acyl chains. No evidence is obtained for preferential orientation of halothane molecules with respect to the lipid/water interface. The overall dynamics of the lipid-bound halothane molecules appears to be reminiscent of that of other small solutes (Bassolino-Klimas et al., 1995. J. Am. Chem. Soc. 117:4118-4129).
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Affiliation(s)
- K Tu
- Center for Molecular Modeling, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA
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Owensby JE, Elliott S, Tu K, Hernandez JE. Cellulitis and myositis caused by Agrobacterium radiobacter and Haemophilus parainfluenzae after influenza virus vaccination. South Med J 1997; 90:752-4. [PMID: 9225903 DOI: 10.1097/00007611-199707000-00022] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Agrobacterium radiobacter is a gram-negative aerobic bacillus that has been reported as a cause of disease only 36 times in the literature. More than half of the patients (25) have had bacteremia. Peritonitis, urinary tract infection, endocarditis, and one case of cellulitis associated with bacteremia have also been reported. Infection is often associated with immunosuppression and the presence of a plastic foreign body, such as central venous catheters, nephrostomy tubes, intraperitoneal catheters, and prosthetic cardiac valves. We present apparently the first case of A radiobacter causing myositis after influenza virus vaccination.
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Affiliation(s)
- J E Owensby
- Department of Internal Medicine, West Virginia University-Charleston Division, USA
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Tu K, Tobias DJ, Blasie JK, Klein ML. Molecular dynamics investigation of the structure of a fully hydrated gel-phase dipalmitoylphosphatidylcholine bilayer. Biophys J 1996; 70:595-608. [PMID: 8789079 PMCID: PMC1224962 DOI: 10.1016/s0006-3495(96)79623-6] [Citation(s) in RCA: 137] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
We report the results of a constant pressure and temperature molecular dynamics simulation of a gel-phase dipalmitoylphosphatidylcholine bilayer with nw = 11.8 water molecules/lipid at 19 degrees C. The results of the simulation were compared in detail with a variety of x-ray and neutron diffraction data. The average positions of specific carbon atoms along the bilayer normal and the interlamellar spacing and electron density profile were in very good agreement with neutron and x-ray diffraction results. The area per lipid and the details of the in-plane hydrocarbon chain structure were in excellent agreement with wide-angle x-ray diffraction results. The only significant deviation is that the chains met in a pleated arrangement at the bilayer center, although they should be parallel. Novel discoveries made in the present work include the observation of a bimodal headgroup orientational distribution. Furthermore, we found that there are a significant number of gauche conformations near the ends of the hydrocarbon chains and, in addition to verifying a previous suggestion that there is partial rotational ordering in the hydrocarbon chains, that the two chains in a given molecule are inequivalent with respect to rotations. Finally, we have investigated the lipid/water interface and found that the water penetrates beneath the headgroups, but not as far as the carbonyl groups, that the phosphates are strongly hydrated almost exclusively at the nonesterified oxygen atoms, and that the hydration of the ammonium groups is more diffuse, with some water molecules concentrated in the grooves between the methyl groups.
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Affiliation(s)
- K Tu
- Department of Chemistry, University of Pennsylvania, Philadelphia 19104-6323, USA
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Tu K, Tobias DJ, Klein ML. Constant pressure and temperature molecular dynamics simulation of a fully hydrated liquid crystal phase dipalmitoylphosphatidylcholine bilayer. Biophys J 1995; 69:2558-62. [PMID: 8599662 PMCID: PMC1236493 DOI: 10.1016/s0006-3495(95)80126-8] [Citation(s) in RCA: 184] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We report a constant pressure and temperature molecular dynamics simulation of a fully hydrated liquid crystal (L alpha) phase bilayer of dipalmitoylphosphatidylcholine at 50 degrees C and 28 water molecules/lipid. We have shown that the bilayer is stable throughout the 1550-ps simulation and have demonstrated convergence of the system dimensions. Several important aspects of the bilayer structure have been investigated and compared favorably with experimental results. For example, the average positions of specific carbon atoms along the bilayer normal agree well with neutron diffraction data, and the electron density profile is in accord with x-ray diffraction results. The hydrocarbon chain deuterium order parameters agree reasonably well with NMR results for the middles of the chains, but the simulation predicts too much order at the chain ends. In spite of the deviations in the order parameters, the hydrocarbon chain packing density appears to be essentially correct, inasmuch as the area/lipid and bilayer thickness are in agreement with the most refined experimental estimates. The deuterium order parameters for the glycerol and choline groups, as well as the phosphorus chemical shift anisotropy, are in qualitative agreement with those extracted from NMR measurements.
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Affiliation(s)
- K Tu
- Department of Chemistry, University of Pennsylvania, Philadelphia 19104-6323, USA
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Dai L, Cheng P, Tu K, Xu Y, Zhang W. The effect of posterior element resection on the stress distribution in the lumbar spine. Chin Med Sci J 1995; 10:113-5. [PMID: 7647317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A three-dimensional finite element model of the lumbar motion segment was used to predict the stress distribution in lumbar spine with posterior element resection. It was shown that the stress level in all parts of the lumbar spine was elevated although the stress distribution remained unchanged. The authors concluded that the posterior element resection in lumbar surgery should be avoided as much as possible.
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Affiliation(s)
- L Dai
- Department of Orthopedics, Changzheng Hospital, Shanghai
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Dai L, Cheng P, Tu K, Xu Y, Zhang W. The stress distribution of the lumbar spine and disc degeneration. Chin Med Sci J 1992; 7:166-8. [PMID: 1286185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A three-dimensional finite element model of the lumbar motion segment was developed to study the effect of disc degeneration upon stress distribution in the lumbar spine. The results showed that after degeneration of the intervertebral disc, the stress distribution and load transmission of the lumbar spine are significantly changed. It is concluded that these changes provide a biomechanical basis for understanding the etiology of spinal canal stenosis and nerve root entrapment.
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Affiliation(s)
- L Dai
- Department of Orthopedics, Changzheng Hospital, Shanghai
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Dai L, Cheng P, Zhang W, Xu Y, Tu K. Stress distribution and bone density in the lumbar spine. Chin Med Sci J 1992; 7:105-7. [PMID: 1450391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The stress distribution of the lumbar spine was analyzed with a mechanical model of the lumbar motion segment constructed by a three-dimensional finite element method, and the results were compared with the corresponding bone density represented by the value of CT. The results showed that the stress levels in the various parts of the lumbar spine were closely related to the CT values. The authors conclude that the dynamic balance of bone growth is maintained in large part by mechanical stress.
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Affiliation(s)
- L Dai
- Changzheng Hospital, Shanghai
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