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Johnson AEW, Bulgarelli L, Shen L, Gayles A, Shammout A, Horng S, Pollard TJ, Hao S, Moody B, Gow B, Lehman LWH, Celi LA, Mark RG. Author Correction: MIMIC-IV, a freely accessible electronic health record dataset. Sci Data 2023; 10:219. [PMID: 37072428 PMCID: PMC10113185 DOI: 10.1038/s41597-023-02136-9] [Citation(s) in RCA: 3] [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] [Indexed: 04/20/2023] Open
Affiliation(s)
- Alistair E W Johnson
- Massachusetts Institute of Technology, Cambridge, MA, USA.
- The Hospital for Sick Children, Toronto, ON, Canada.
| | | | - Lu Shen
- Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Alvin Gayles
- Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Ayad Shammout
- Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Steven Horng
- Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Tom J Pollard
- Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Sicheng Hao
- Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Benjamin Moody
- Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Brian Gow
- Massachusetts Institute of Technology, Cambridge, MA, USA
| | | | - Leo A Celi
- Massachusetts Institute of Technology, Cambridge, MA, USA
- Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Roger G Mark
- Massachusetts Institute of Technology, Cambridge, MA, USA
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2
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Johnson AEW, Bulgarelli L, Shen L, Gayles A, Shammout A, Horng S, Pollard TJ, Moody B, Gow B, Lehman LWH, Celi LA, Mark RG. Author Correction: MIMIC-IV, a freely accessible electronic health record dataset. Sci Data 2023; 10:31. [PMID: 36646711 PMCID: PMC9842744 DOI: 10.1038/s41597-023-01945-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Affiliation(s)
- Alistair E. W. Johnson
- grid.116068.80000 0001 2341 2786Massachusetts Institute of Technology, Cambridge, MA USA ,grid.42327.300000 0004 0473 9646The Hospital for Sick Children, Toronto, ON Canada
| | - Lucas Bulgarelli
- grid.116068.80000 0001 2341 2786Massachusetts Institute of Technology, Cambridge, MA USA
| | - Lu Shen
- grid.239395.70000 0000 9011 8547Beth Israel Deaconess Medical Center, Boston, MA USA
| | - Alvin Gayles
- grid.239395.70000 0000 9011 8547Beth Israel Deaconess Medical Center, Boston, MA USA
| | - Ayad Shammout
- grid.239395.70000 0000 9011 8547Beth Israel Deaconess Medical Center, Boston, MA USA
| | - Steven Horng
- grid.239395.70000 0000 9011 8547Beth Israel Deaconess Medical Center, Boston, MA USA
| | - Tom J. Pollard
- grid.116068.80000 0001 2341 2786Massachusetts Institute of Technology, Cambridge, MA USA
| | - Benjamin Moody
- grid.116068.80000 0001 2341 2786Massachusetts Institute of Technology, Cambridge, MA USA
| | - Brian Gow
- grid.116068.80000 0001 2341 2786Massachusetts Institute of Technology, Cambridge, MA USA
| | - Li-wei H. Lehman
- grid.116068.80000 0001 2341 2786Massachusetts Institute of Technology, Cambridge, MA USA
| | - Leo A. Celi
- grid.116068.80000 0001 2341 2786Massachusetts Institute of Technology, Cambridge, MA USA ,grid.239395.70000 0000 9011 8547Beth Israel Deaconess Medical Center, Boston, MA USA
| | - Roger G. Mark
- grid.116068.80000 0001 2341 2786Massachusetts Institute of Technology, Cambridge, MA USA
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Zhou Y, Zhao G, Li J, Sun G, Qian X, Moody B, Mark RG, Lehman LWH. A contrastive learning approach for ICU false arrhythmia alarm reduction. Sci Rep 2022; 12:4689. [PMID: 35304473 PMCID: PMC8933571 DOI: 10.1038/s41598-022-07761-9] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 02/07/2022] [Indexed: 11/16/2022] Open
Abstract
The high rate of false arrhythmia alarms in Intensive Care Units (ICUs) can lead to disruption of care, negatively impacting patients’ health through noise disturbances, and slow staff response time due to alarm fatigue. Prior false-alarm reduction approaches are often rule-based and require hand-crafted features from physiological waveforms as inputs to machine learning classifiers. Despite considerable prior efforts to address the problem, false alarms are a continuing problem in the ICUs. In this work, we present a deep learning framework to automatically learn feature representations of physiological waveforms using convolutional neural networks (CNNs) to discriminate between true vs. false arrhythmia alarms. We use Contrastive Learning to simultaneously minimize a binary cross entropy classification loss and a proposed similarity loss from pair-wise comparisons of waveform segments over time as a discriminative constraint. Furthermore, we augment our deep models with learned embeddings from a rule-based method to leverage prior domain knowledge for each alarm type. We evaluate our method using the dataset from the 2015 PhysioNet Computing in Cardiology Challenge. Ablation analysis demonstrates that Contrastive Learning significantly improves the performance of a combined deep learning and rule-based-embedding approach. Our results indicate that the final proposed deep learning framework achieves superior performance in comparison to the winning entries of the Challenge.
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Affiliation(s)
| | | | - Jun Li
- Nanjing University of Science and Technology, Nanjing, China
| | - Gan Sun
- Chinese Academy of Sciences, Shenyang, China
| | | | - Benjamin Moody
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Roger G Mark
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Li-Wei H Lehman
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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4
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Clifford GD, Liu C, Moody B, Lehman LWH, Silva I, Li Q, Johnson AE, Mark RG. AF Classification from a Short Single Lead ECG Recording: the PhysioNet/Computing in Cardiology Challenge 2017. Comput Cardiol (2010) 2018; 44. [PMID: 29862307 DOI: 10.22489/cinc.2017.065-469] [Citation(s) in RCA: 135] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The PhysioNet/Computing in Cardiology (CinC) Challenge 2017 focused on differentiating AF from noise, normal or other rhythms in short term (from 9-61 s) ECG recordings performed by patients. A total of 12,186 ECGs were used: 8,528 in the public training set and 3,658 in the private hidden test set. Due to the high degree of inter-expert disagreement between a significant fraction of the expert labels we implemented a mid-competition bootstrap approach to expert relabeling of the data, levering the best performing Challenge entrants' algorithms to identify contentious labels. A total of 75 independent teams entered the Challenge using a variety of traditional and novel methods, ranging from random forests to a deep learning approach applied to the raw data in the spectral domain. Four teams won the Challenge with an equal high F1 score (averaged across all classes) of 0.83, although the top 11 algorithms scored within 2% of this. A combination of 45 algorithms identified using LASSO achieved an F1 of 0.87, indicating that a voting approach can boost performance.
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Affiliation(s)
- Gari D Clifford
- Department of Biomedical Informatics, Emory University, Atlanta, USA.,Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, USA
| | - Chengyu Liu
- Department of Biomedical Informatics, Emory University, Atlanta, USA.,School of Instrument Science and Engineering, Southeast University, Nanjing, China
| | - Benjamin Moody
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, USA
| | - Li-Wei H Lehman
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, USA
| | - Ikaro Silva
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, USA
| | - Qiao Li
- Department of Biomedical Informatics, Emory University, Atlanta, USA
| | - A E Johnson
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, USA
| | - Roger G Mark
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, USA
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5
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Trad M, Boyer S, VanBelle C, Hughes L, Moody B. Advancing drug development in neuro-orphan indications. J Neurol Sci 2017. [DOI: 10.1016/j.jns.2017.08.2725] [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: 11/16/2022]
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6
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Affiliation(s)
- Gari D Clifford
- Department of Biomedical Informatics, Emory University, Atlanta, GA, United States of America. Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, United States of America
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7
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Liu C, Springer D, Li Q, Moody B, Juan RA, Chorro FJ, Castells F, Roig JM, Silva I, Johnson AE, Syed Z, Schmidt SE, Papadaniil CD, Hadjileontiadis L, Naseri H, Moukadem A, Dieterlen A, Brandt C, Tang H, Samieinasab M, Samieinasab MR, Sameni R, Mark RG, Clifford GD. An open access database for the evaluation of heart sound algorithms. Physiol Meas 2016; 37:2181-2213. [PMID: 27869105 PMCID: PMC7199391 DOI: 10.1088/0967-3334/37/12/2181] [Citation(s) in RCA: 206] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In the past few decades, analysis of heart sound signals (i.e. the phonocardiogram or PCG), especially for automated heart sound segmentation and classification, has been widely studied and has been reported to have the potential value to detect pathology accurately in clinical applications. However, comparative analyses of algorithms in the literature have been hindered by the lack of high-quality, rigorously validated, and standardized open databases of heart sound recordings. This paper describes a public heart sound database, assembled for an international competition, the PhysioNet/Computing in Cardiology (CinC) Challenge 2016. The archive comprises nine different heart sound databases sourced from multiple research groups around the world. It includes 2435 heart sound recordings in total collected from 1297 healthy subjects and patients with a variety of conditions, including heart valve disease and coronary artery disease. The recordings were collected from a variety of clinical or nonclinical (such as in-home visits) environments and equipment. The length of recording varied from several seconds to several minutes. This article reports detailed information about the subjects/patients including demographics (number, age, gender), recordings (number, location, state and time length), associated synchronously recorded signals, sampling frequency and sensor type used. We also provide a brief summary of the commonly used heart sound segmentation and classification methods, including open source code provided concurrently for the Challenge. A description of the PhysioNet/CinC Challenge 2016, including the main aims, the training and test sets, the hand corrected annotations for different heart sound states, the scoring mechanism, and associated open source code are provided. In addition, several potential benefits from the public heart sound database are discussed.
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Affiliation(s)
- Chengyu Liu
- Department of Biomedical Informatics, Emory University, USA
| | - David Springer
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, UK
| | - Qiao Li
- Department of Biomedical Informatics, Emory University, USA
| | - Benjamin Moody
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, USA
| | - Ricardo Abad Juan
- Department of Biomedical Engineering, Georgia Institute of Technology, USA
- ITACA Institute, Universitat Politecnica de Valencia, Spain
| | - Francisco J Chorro
- Service of Cardiology, Valencia University Clinic Hospital, INCLIVA, Spain
| | | | | | - Ikaro Silva
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, USA
| | - Alistair E.W. Johnson
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, USA
| | - Zeeshan Syed
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Samuel E. Schmidt
- Department of Health Science and Technology, Aalborg University, Denmark
| | - Chrysa D. Papadaniil
- Department of Electrical and Computer Engineering, Aristotle University of Thessaloniki, Greece
| | | | - Hosein Naseri
- Department of Mechanical Engineering, K. N. Toosi University of Technology, Iran
| | - Ali Moukadem
- MIPS Laboratory, University of Haute Alsace, France
| | | | | | - Hong Tang
- Faculty of Electronic and Electrical Engineering, Dalian University of Technology, China
| | - Maryam Samieinasab
- School of Electrical & Computer Engineering, Shiraz University, Shiraz, Iran
| | | | - Reza Sameni
- School of Electrical & Computer Engineering, Shiraz University, Shiraz, Iran
| | - Roger G. Mark
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, USA
| | - Gari D. Clifford
- Department of Biomedical Informatics, Emory University, USA
- Department of Biomedical Engineering, Georgia Institute of Technology, USA
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8
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Abstract
High false alarm rates in the ICU decrease quality of care by slowing staff response times while increasing patient delirium through noise pollution. The 2015 PhysioNet/Computing in Cardiology Challenge provides a set of 1250 multi-parameter ICU data segments associated with critical arrhythmia alarms, and challenges the general research community to address the issue of false alarm suppression using all available signals. Each data segment was 5 minutes long (for real time analysis), ending at the time of the alarm. For retrospective analysis, we provided a further 30 seconds of data after the alarm was triggered. A total of 750 data segments were made available for training and 500 were held back for testing. Each alarm was reviewed by expert annotators, at least two of whom agreed that the alarm was either true or false. Challenge participants were invited to submit a complete, working algorithm to distinguish true from false alarms, and received a score based on their program's performance on the hidden test set. This score was based on the percentage of alarms correct, but with a penalty that weights the suppression of true alarms five times more heavily than acceptance of false alarms. We provided three example entries based on well-known, open source signal processing algorithms, to serve as a basis for comparison and as a starting point for participants to develop their own code. A total of 38 teams submitted a total of 215 entries in this year's Challenge. This editorial reviews the background issues for this challenge, the design of the challenge itself, the key achievements, and the follow-up research generated as a result of the Challenge, published in the concurrent special issue of Physiological Measurement. Additionally we make some recommendations for future changes in the field of patient monitoring as a result of the Challenge.
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Affiliation(s)
- Gari D Clifford
- Department of Biomedical Informatics, Emory University, Atlanta GA, USA. Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta GA, USA
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9
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Johnson AEW, Pollard TJ, Shen L, Lehman LWH, Feng M, Ghassemi M, Moody B, Szolovits P, Celi LA, Mark RG. MIMIC-III, a freely accessible critical care database. Sci Data 2016; 3:160035. [PMID: 27219127 PMCID: PMC4878278 DOI: 10.1038/sdata.2016.35] [Citation(s) in RCA: 2488] [Impact Index Per Article: 311.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 04/25/2016] [Indexed: 12/11/2022] Open
Abstract
MIMIC-III (‘Medical Information Mart for Intensive Care’) is a large, single-center database comprising information relating to patients admitted to critical care units at a large tertiary care hospital. Data includes vital signs, medications, laboratory measurements, observations and notes charted by care providers, fluid balance, procedure codes, diagnostic codes, imaging reports, hospital length of stay, survival data, and more. The database supports applications including academic and industrial research, quality improvement initiatives, and higher education coursework.
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Affiliation(s)
- Alistair E W Johnson
- Laboratory for Computational Physiology, MIT Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Tom J Pollard
- Laboratory for Computational Physiology, MIT Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Lu Shen
- Information Systems, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA
| | - Li-Wei H Lehman
- Laboratory for Computational Physiology, MIT Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Mengling Feng
- Laboratory for Computational Physiology, MIT Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.,Data Analytics Department, Institute for Infocomm Research, A*STAR, Singapore 138632, Singapore
| | - Mohammad Ghassemi
- Laboratory for Computational Physiology, MIT Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Benjamin Moody
- Laboratory for Computational Physiology, MIT Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Peter Szolovits
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Leo Anthony Celi
- Laboratory for Computational Physiology, MIT Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.,Information Systems, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA
| | - Roger G Mark
- Laboratory for Computational Physiology, MIT Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.,Information Systems, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA
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10
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Souter MN, Nguyen-Robertson CV, Ross FJ, Reddiex SJJ, Waddington J, Van Rhijn I, Eckle SBG, McCluskey J, Aldrich AP, Rossjohn J, Moody B, Godfrey DI, Pellicci DG. Identification and characterization of CD1-restricted T cells. The Journal of Immunology 2016. [DOI: 10.4049/jimmunol.196.supp.206.6] [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] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
Most studies of T cells have focused on those that respond to foreign peptides. However, other specialized populations of T cells exist that recognize lipid antigens and make up a substantial component of the human immune system. These lipid reactive T cells recognize antigens presented by antigen presentation molecules from the CD1 family. Four CD1 molecules exist (CD1a, CD1b, CD1c and CD1d), and each is capable of presenting a unique repertoire of lipids antigens to T cells. Much of what we have learned about lipid reactive T cells stems from studies of CD1d restricted NKT cells as these are present is both mice and humans and can be detected using CD1d/α-GalCer tetramers. In contrast, our understanding of the biology of CD1a, CD1b, CD1c restricted T cells is relatively limited. However, the recent generation of CD1a, CD1b and CD1c tetramers is helping with the identification and characterisation of these CD1-restricted T cells.
We have produced CD1 tetramers loaded with mammalian self-lipids or lipid antigens from Mycobacterium tuberculosis. In conjunction, with a tetramer-based enrichment method, we have successfully identified both autoreactive and microbial lipid antigen specific T cells from healthy human blood. We reveal the phenotypic characteristics of these CD1-restricted T cells and used CD1 mutagenesis to provide new insight into TCR recognition of CD1-lipid antigen complexes. Collectively, these studies will serve as a basis for future studies of lipid reactive T cells in health and disease.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - J Rossjohn
- 4Monash Univ., Australia
- 5Cardiff Univ., United Kingdom
| | - B Moody
- 2Harvard Med. Sch
- 6Brigham and Women’s Hosp., Australia
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11
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Clifford GD, Silva I, Moody B, Li Q, Kella D, Shahin A, Kooistra T, Perry D, Mark RG. The PhysioNet/Computing in Cardiology Challenge 2015: Reducing False Arrhythmia Alarms in the ICU. Comput Cardiol (2010) 2015; 2015:273-276. [PMID: 27331073 DOI: 10.1109/cic.2015.7408639] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
High false alarm rates in the ICU decrease quality of care by slowing staff response times while increasing patient delirium through noise pollution. The 2015 Physio-Net/Computing in Cardiology Challenge provides a set of 1,250 multi-parameter ICU data segments associated with critical arrhythmia alarms, and challenges the general research community to address the issue of false alarm suppression using all available signals. Each data segment was 5 minutes long (for real time analysis), ending at the time of the alarm. For retrospective analysis, we provided a further 30 seconds of data after the alarm was triggered. A collection of 750 data segments was made available for training and a set of 500 was held back for testing. Each alarm was reviewed by expert annotators, at least two of whom agreed that the alarm was either true or false. Challenge participants were invited to submit a complete, working algorithm to distinguish true from false alarms, and received a score based on their program's performance on the hidden test set. This score was based on the percentage of alarms correct, but with a penalty that weights the suppression of true alarms five times more heavily than acceptance of false alarms. We provided three example entries based on well-known, open source signal processing algorithms, to serve as a basis for comparison and as a starting point for participants to develop their own code. A total of 38 teams submitted a total of 215 entries in this year's Challenge.
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Affiliation(s)
- Gari D Clifford
- Department of Biomedical Informatics, Emory University, Atlanta, GA USA; Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Ikaro Silva
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, USA
| | - Benjamin Moody
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, USA
| | - Qiao Li
- Department of Biomedical Informatics, Emory University, Atlanta, GA USA
| | - Danesh Kella
- Emory School of Medicine, Emory Univesrity, Atlanta, GA
| | - Abdullah Shahin
- Beth Israel Medical Center, Harvard University, Boston MA, USA
| | | | - Diane Perry
- Beth Israel Medical Center, Harvard University, Boston MA, USA
| | - Roger G Mark
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, USA
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12
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Abstract
This editorial reviews the background issues, the design, the key achievements, and the follow-up research generated as a result of the PhysioNet/Computing in Cardiology (CinC) Challenge 2014, published in the concurrent focus issue of Physiological Measurement. Our major focus was to accelerate the development and facilitate the comparison of robust methods for locating heart beats in long-term multi-channel recordings. A public (training) database consisting of 151 032 annotated beats was compiled from records that contained ECGs as well as pulsatile signals that directly reflect cardiac activity, and other signals that may have few or no observable markers of heart beats. A separate hidden test data set (consisting of 152 478 beats) is permanently stored at PhysioNet, and a public framework has been developed to provide researchers with the ability to continue to automatically score and compare the performance of their algorithms. A scoring criteria based on the averaging of gross sensitivity, gross positive predictivity, average sensitivity, and average positive predictivity is proposed. The top three scores (as of March 2015) on the hidden test data set were 93.64%, 91.50%, and 90.70%.
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Affiliation(s)
- Ikaro Silva
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139, USA
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13
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Alavi-Naini R, Salimi S, Sharifi-Mood B, Davoodikia AA, Moody B, Naghavi A. Association between the CD14 gene C-159T polymorphism and serum soluble CD14 with pulmonary tuberculosis. Int J Tuberc Lung Dis 2013; 16:1383-7. [PMID: 23107636 DOI: 10.5588/ijtld.11.0827] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Functional C-159T polymorphism in the promoter region of the CD14 lipopolysaccharide receptor has been reported to be associated with the development of tuberculosis (TB). OBJECTIVE To assess the association of CD14 C-159T polymorphism and serum soluble CD14 (sCD14) levels with pulmonary tuberculosis (TB) in an Iranian population living in a TB-endemic area. DESIGN A case-control study was performed prospectively on 120 newly diagnosed pulmonary TB patients and 131 healthy subjects. C-159T polymorphism was performed using amplification refractory mutation system polymerase chain reaction (ARMS-PCR). Concentrations of sCD14 were measured in serum samples using enzyme-linked immunosorbent assay. RESULTS The genotype frequencies of C-159T polymorphism differed significantly between TB patients and controls (P = 0.006). The risk of TB was 2.3-fold greater in individuals with the T-allele (CT + TT) in comparison to those without (OR 2.3, 95%CI 1.2-4.3, P = 0.006). Mean total sCD14 was significantly increased in the serum of patients with newly diagnosed pulmonary TB (mean ± SD = 3177 ± 751 ng/ml) compared to healthy controls (mean ± SD = 2955 ± 424 ng/ml, P < 0.004). CONCLUSION These data indicate that the C-159T polymorphism of the CD14 gene is associated with TB; serum sCD14 levels were higher in TB patients in a sample of the Iranian population.
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Affiliation(s)
- R Alavi-Naini
- Infectious Diseases and Tropical Medicine Research Center, Zahedan University of Medical Sciences, Zahedan, Iran
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14
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Wunderer T, Chua CL, Northrup JE, Yang Z, Johnson NM, Kneissl M, Garrett GA, Shen H, Wraback M, Moody B, Craft HS, Schlesser R, Dalmau RF, Sitar Z. Optically pumped UV lasers grown on bulk AlN substrates. ACTA ACUST UNITED AC 2012. [DOI: 10.1002/pssc.201100424] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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15
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Moody B, Haslauer CM, Kirk E, Kannan A, Loboa EG, McCarty GS. In situ monitoring of adipogenesis with human-adipose-derived stem cells using surface-enhanced Raman spectroscopy. Appl Spectrosc 2010; 64:1227-1233. [PMID: 21073790 DOI: 10.1366/000370210793335106] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Methods capable of nondestructively collecting high-quality, real-time chemical information from living human stem cells are of increasing importance given the escalating relevance of stem cells in therapeutic and regenerative medicines. Raman spectroscopy is one such technique that can nondestructively collect real-time chemical information. Living cells uptake gold nanoparticles and transport these particles through an endosomal pathway. Once inside the endosome, nanoparticles aggregate into clusters that give rise to large spectroscopic enhancements that can be used to elucidate local chemical environments through the use of surface-enhanced Raman spectroscopy. This report uses 40-nm colloidal gold nanoparticles to create volumes of surface-enhanced Raman scattering (SERS) within living human-adipose-derived adult stem cells enabling molecular information to be monitored. We exploit this method to spectroscopically observe chemical changes that occur during the adipogenic differentiation of human-adipose-derived stem cells over a period of 22 days. It is shown that intracellular SERS is able to detect the production of lipids as little as one day after the onset of adipogenesis and that a complex interplay between lipids, proteins, and chemical messengers can be observed shortly thereafter. After 22 days of differentiation, the cells show visible and spectroscopic indications of completed adipogenesis yet still share spectral features common to the progenitor stem cells.
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Affiliation(s)
- Benjamin Moody
- University of North Carolina, Chapel Hill and North Carolina State University, Joint Department of Biomedical Engineering, Raleigh, North Carolina 27695, USA
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16
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Abstract
This report highlights methodologies that enable statistically significant data to be collected for single nucleotide polymorphisms using surface enhanced Raman spectroscopy. Single-stranded oligonucleotides functionalized with 40 nm gold nanoparticles are hybridized with oligonucleotides adsorbed to a photolithographically defined gold surface thus creating a surface enhanced Raman environment around the DNA duplex. With this design characteristic Raman spectra have been collected and explored for differences between DNA duplexes formed from complementary oligonucleotides, completely mismatched oligonucleotides, and those formed from oligonucleotides that have a midsequence single nucleotide mismatch. The results show that statistically significant differences in Raman intensity for characteristic peaks can be collected for the three cases.
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Affiliation(s)
- Benjamin Moody
- North Carolina State University, 2147 Burlington Laboratories, Raleigh, North Carolina 27695, USA
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Zachek MK, Takmakov P, Moody B, Wightman RM, McCarty GS. Simultaneous decoupled detection of dopamine and oxygen using pyrolyzed carbon microarrays and fast-scan cyclic voltammetry. Anal Chem 2010; 81:6258-65. [PMID: 19552423 DOI: 10.1021/ac900790m] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Microfabricated structures utilizing pyrolyzed photoresist have been shown to be useful for monitoring electrochemical processes. These previous studies, however, were limited to constant-potential measurements and slow-scan voltammetry. The work described in this paper utilizes microfabrication processes to produce devices that enable multiple fast-scan cyclic voltammetry (FSCV) waveforms to be applied to different electrodes on a single substrate. This enabled the simultaneous, decoupled detection of dopamine and oxygen. In this paper we describe the fabrication process of these arrays and show that pyrolyzed photoresist electrodes possess surface chemistry and electrochemical properties comparable to PAN-type, T-650, carbon fiber microelectrodes using background-subtracted FSCV. The functionality of the array is discussed in terms of the degree of cross talk in response to flow injections of physiologically relevant concentrations of dopamine and oxygen. Finally, other applications of pyrolyzed photoresist microelectrode arrays are shown, including spatially resolved detection of analytes and combining FSCV with amperometry for the detection of dopamine.
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Affiliation(s)
- Matthew K Zachek
- Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, North Carolina 27695, USA
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18
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Mafi R, Sirouspour S, Mahdavikhah B, Moody B, Elizeh K, Kinsman A, Nicolici N. A Parallel Computing Platform for Real-Time Haptic Interaction with Deformable Bodies. IEEE Trans Haptics 2010; 3:211-223. [PMID: 27788075 DOI: 10.1109/toh.2009.50] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Real-time simulation of haptic interaction with deformable objects is computationally demanding. In particular in finite-element (FE) based analysis of such interactions, a large system of equations must be solved at an update rate of 100-1,000 Hz for simulation fidelity and stability. A new hardware-based parallel implementation of a Preconditioned Conjugate Gradient (PCG) algorithm is proposed for solving the linear systems of equations arising from FE-based deformation models. Concurrent utilization of a large number of fixed-point computing units on a Field-Programmable Gate Array (FPGA) device yields a very fast solution to these equations. Quantization and overflow errors in the fixed-point implementation of the iterative solver are minimized through dynamic scaling and preconditioning. Numerical accuracy of the solution, the architecture design, and issues pertaining to the degree of parallelism and scalability of the architecture are discussed in detail. The implementation of the solver on an Altera EP3SE110 FPGA device has enabled real-time simulation of three-dimensional linear elastic deformation models with 1,500 nodes at an update rate of up to 2,500 Hz.
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Abstract
The ability to quickly and inexpensively fabricate planar solid state nanogaps has enabled research to be effectively performed on devices down to just a few nanometers. Here, nanofabricated electrode pairs with electrode-to-electrode spacings of <4, 6 and 20 nm are utilized for monitoring an electroactive molecules, dopamine, in ionic solution. The results show a several order of magnitude enhancement of the electrochemical signal, collected current, for the solid state nanogaps with 6 nm electrode-electrode spacings as compared to traditional microelectrodes. The data from the <4 nm and 20 nm solid state nanogaps verify that this enhancement is due to cycling of the redox molecules in the confined geometry of the nanogap. In addition the data collected for the <4 nm nanogap emphasizes and reinforces that scaling does have limits and that as device sizes move to the few nanometer scale, the influence of a molecule's size and other physical properties becomes increasingly important and can eventually dominate the generated signals.
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Affiliation(s)
- Gregory S. McCarty
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh NC 27695
| | - Benjamin Moody
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh NC 27695
| | - Matthew K. Zachek
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh NC 27695
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20
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Moody B, Leotaud J, McCarty GS. Using surface-enhanced Raman spectroscopy to probe for genetic markers on single-stranded DNA. J Biomed Opt 2010; 15:027014. [PMID: 20459288 DOI: 10.1117/1.3400702] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Methods capable of quickly and inexpensively collecting genetic information are of increasing importance. We report a method of using surface-enhanced Raman spectroscopy to probe single-stranded DNA for genetic markers. This unique approach is used to analyze unmodified genes of moderate length for genetic markers by hybridizing native test oligonucleotides into a surface-enhanced Raman complex, vastly increasing detection sensitivity as compared to traditional Raman spectroscopy. The Raman complex is formed by sandwiching the test DNA between 40-nm gold nanoparticles and a photolithographically defined gold surface. With this design, we are able to collect characteristic Raman spectra about the test DNA and to detect genetic markers such as single-nucleotide polymorphisms (SNPs) and polymorphic regions. Results show that strands containing one of three different types of polymorphism can be differentiated using statistically significant trends regarding Raman intensity.
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Affiliation(s)
- Benjamin Moody
- University of North Carolina, Chapel Hill and North Carolina State University, Joint Department of Biomedical Engineering, 2140 Burlington Labs, 2500 Stinson Drive, Raleigh, North Carolina 27695, USA.
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21
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Moody B, McCarty GS. Solid state nanogaps for differential measurements of molecular properties. Appl Phys Lett 2009; 94:122104. [PMID: 23696694 PMCID: PMC3645910 DOI: 10.1063/1.3103616] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Accepted: 02/27/2009] [Indexed: 05/31/2023]
Abstract
This paper demonstrates the production and probing of solid state nanogaps. These nanogaps can be inexpensively and controllably produced using a combination of molecular and standard photolithography. These nanogaps are implemented for chemical monitoring by using surface enhanced Raman spectroscopy to collect molecular information at the nanogap and current-voltage traces to probe the charge transport of the nanogap. These data show that the oligonucleotides used as the molecular resist are degraded, that some of the degraded oligonucleotides are removed, and then new oligonucleotides are adsorbed.
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Affiliation(s)
- Benjamin Moody
- North Carolina State University, 2147 Burlington Labs, Raleigh, North Carolina 27695, USA
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22
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Goodman T, Doell L, Moody B. Designing a Dynamic APIC Chapter Website: Enhancing Professional Practice and Increasing Member Participation. Am J Infect Control 2006. [DOI: 10.1016/j.ajic.2006.05.111] [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: 12/01/2022]
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23
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Hooper L, Griffiths E, Abrahams B, Alexander W, Atkins S, Atkinson G, Bamford R, Chinuck R, Farrington J, Gardner E, Greene P, Gunner C, Hamer C, Helby B, Hetherington S, Howson R, Laidlaw J, Li M, Lynas J, McVicar C, Mead A, Moody B, Paterson K, Neal S, Rigby P, Ross F, Shaw H, Stone D, Taylor F, Van Rensburgh L, Vine R, Whitehead J, Wray L. Dietetic guidelines: diet in secondary prevention of cardiovascular disease (first update, June 2003). J Hum Nutr Diet 2004; 17:337-49. [PMID: 15250843 DOI: 10.1111/j.1365-277x.2004.00533.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [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: 12/01/2022]
Abstract
AIM To update dietetic guidelines summarizing the systematic review evidence on dietary advice to prevent further events in people with existing cardiovascular disease (CVD) (secondary prevention). METHODS The Cochrane Library, MEDLINE and EMBASE were comprehensively searched to November 2002 for systematic reviews on aspects of diet and heart health. Reviews were included if they searched systematically for randomised controlled trials relating to diet and secondary prevention of CVD. Two members of the UK Heart Health and Thoracic Dietitians Group critically appraised each review. The quality and results of each review were discussed and summarized in a meeting of the whole group. RESULTS Providing evidence-based dietary information (including increasing omega-3 fat intake) to all people who have had a myocardial infarction will save more lives than concentrating dietary advice on just those in need of weight loss or lipid lowering. The practice of prioritizing dietetic time in secondary prevention to those with raised lipids is out of date since the advent of statin therapy. However, effective dietary advice for those with angina, stroke, peripheral vascular disease or heart failure is less clear. CONCLUSION There is good systematic review evidence that dietary advice to those with coronary heart disease can reduce mortality and morbidity as well as modify some risk factors. Dietary advice that does this most effectively should be prioritized.
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Affiliation(s)
- L Hooper
- MANDEC, University Dental Hospital of Manchester, Manchester, UK.
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24
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Abstract
BACKGROUND The diagnosis of Barrett's esophagus (BE) has important psychological and economic implications. Although accepted standards for endoscopic biopsy methods and pathological interpretation for BE exist, adherence to these standards as a measure of the quality of care in BE has not been evaluated. Our aim was to assess the quality of care in BE by evaluating the process of care and adherence to accepted standards of practice. METHODS Explicit process-of-care criteria were developed using a systematic literature review and expert opinion in four domains of care: the quality of biopsy methods, the adequacy in identifying endoscopic landmarks, endoscopist-pathologist communication, and pathological interpretation and reporting. We reviewed all endoscopy and pathology reports of BE patients at two institutions from 1994-1997. An academic medical center (N = 237) with staff endoscopists and an academically affiliated community hospital (N = 100) with private-practice endoscopists were analyzed. RESULTS Physicians showed the highest adherence to accepted standards of care in the "adequacy of identifying landmarks" and "endoscopist-pathologist communication" domains, with a > or =70% adherence rate in most criteria. Conversely, physicians demonstrated the poorest adherence with the "quality of biopsy methods" and "pathologist interpretation and reporting" domains, with adherence rates frequently <60%. Significantly, biopsies were taken in the presence of visible esophagitis 35% of the time. Performance on several of the quality indicators varied significantly by the practice setting. CONCLUSIONS We have identified several opportunities for quality improvement efforts. In every domain, there is room for improvement, particularly in the quality of biopsy methods. As initiatives to screen the large population of gastroesophageal reflux disease patients for BE may be imminent, the time is now to define the critical process-of-care measures to minimize the risk of overdiagnosis and inadequate endoscopic surveillance.
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Affiliation(s)
- J J Ofman
- Department of Medicine and Health Services Research, Cedars-Sinai Medical Center, Los Angeles, California, USA
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25
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Longlands MG, Moody B, Wiener K. Automated method for urine 5-hydroxyindole-acetic acid by high-performance liquid chromatography using Gilson ASTED sample preparation unit. Ann Clin Biochem 2001; 38:69-70. [PMID: 11270848 DOI: 10.1258/0004563011900173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- M G Longlands
- Department of Clinical Biochemistry, North Manchester General Hospital, Manchester UK
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26
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Minei JP, Hawkins K, Moody B, Uchal LB, Joy K, Christensen LL, Haley RW. Alternative case definitions of ventilator-associated pneumonia identify different patients in a surgical intensive care unit. Shock 2000; 14:331-6; discussion 336-7. [PMID: 11028552 DOI: 10.1097/00024382-200014030-00016] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [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: 11/27/2022]
Abstract
Diagnostic criteria that define ventilator-associated pneumonia (VAP) remain controversial. The purpose of this study was to evaluate common definitions of VAP and determine their relationship to each other and clinical treatment. This study prospectively evaluated several diagnostic criteria that define VAP in a cohort of 255 consecutive SICU patients ventilated for < 48 h. Definitions evaluated include the CDC definitions, the Johanson definitions which do not rely on culture data, the Physician's Probable diagnosis which relies on positive quantitative cultures, and the antibiotic treatment group. Forty-four patients (17%) received antibiotic treatment for VAP. Depending on the definition evaluated, criteria were met for a diagnosis of VAP from as low as 4% of patients by the Johanson definition to as high as 48% of patients by the CDC definition. There was poor agreement among the definitions in their ability to select the same patient as having VAP. Besides duration of mechanical ventilation and tube feeding, which were risk factors that predicted meeting the criteria for all groups, risk factors predicting VAP varied among the definitions. This study demonstrates that in a surgical ICU, the candidate definitions of pneumonia evaluated show little agreement. The particular case definition chosen to diagnose VAP will determine the incidence rate of pneumonia, the time to onset of pneumonia, and the risk factors of the type of patient treated.
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Affiliation(s)
- J P Minei
- Department of Surgery, University of Texas Southwestern Medical Center, Dallas 75235-9158, USA
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27
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Moody B. Practical application of sharing surveillance data. Crit Care Nurs Clin North Am 1995; 7:719-25. [PMID: 8546831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
This article provides several practical and effective mechanisms for reporting meaningful information on nosocomial infections to critical care and other specific units. Roadblocks and a small sample of hospital practices for reporting unit-specific infections are described. Graphic presentations, especially line-stay histograms, are recommended.
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28
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Moody B. Modern trends in surveillance techniques. Healthtexas 1990; 46:17. [PMID: 10113348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Affiliation(s)
- B Moody
- Seton Medical Center, Austin, TX
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29
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Moody B, McCullough D. Wound complications associated with re-use of disposable bovies. Am J Infect Control 1990. [DOI: 10.1016/0196-6553(90)90123-a] [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: 11/26/2022]
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30
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McCullough D, Moody B, Lewis L. Infection control in a new pulmonary unit: Analysis of the risks. Am J Infect Control 1990. [DOI: 10.1016/0196-6553(90)90148-l] [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: 10/24/2022]
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31
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Craven DE, Moody B, Connolly MG, Kollisch NR, Stottmeier KD, McCabe WR. Pseudobacteremia caused by povidone-iodine solution contaminated with Pseudomonas cepacia. N Engl J Med 1981; 305:621-3. [PMID: 7022209 DOI: 10.1056/nejm198109103051106] [Citation(s) in RCA: 108] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Abstract
Phage T7 adsorbed to and lysed cells of Shigella sonnei D(2) 371-48, although the average burst size was only 0.1 phage per cell (abortive infection). No mechanism of host-controlled modification was involved. Upon infection, T7 rapidly degraded host deoxyribonucleic acid (DNA) to acid-soluble material. Phage-directed DNA synthesis was initiated normally, but after a few minutes the pool of phage DNA, including the parental DNA, was degraded. Addition of chloramphenicol, at the time of phage infection, prevented both the initiation of phage-directed DNA synthesis and the degradation of parental phage DNA. Addition of chloramphenicol 4.5 min after phage was added permitted the onset of phage-directed DNA synthesis but prevented breakdown of phage DNA. Mutants of T7 (ss(-) mutants) have been isolated which show normal growth in strain D(2) 371-48. Upon mixed infection of this strain with T7 wild type and an ss(-) mutant, infection was abortive; no complementation occurred. The DNA of the ss(-) mutants was degraded in mixed infection like that of the wild type. Revertant mutants which have lost their ability to grow on D(2) 371-48 were isolated from ss(-) mutants; they are, in essence, phenotypically like T7 wild type. Independently isolated revertants of ss(-) mutants did not produce ss(-) recombinants when they were crossed among themselves. When independently isolated ss(-) mutants were crossed with each other, wild-type recombinants were found; ss(-) mutants could then be mapped in a cluster compatible with the length of one cistron. We concluded that T7 codes for an active, chloramphenicol-sensitive function [ss(+) function (for suicide in Shigella)] which leads to the breakdown of phage DNA in the Shigella host.
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