1
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Walton NA, Hafen B, Graceffo S, Sutherland N, Emmerson M, Palmquist R, Formea CM, Purcell M, Heale B, Brown MA, Danford CJ, Rachamadugu SI, Person TN, Shortt KA, Christensen GB, Evans JM, Raghunath S, Johnson CP, Knight S, Le VT, Anderson JL, Van Meter M, Reading T, Haslem DS, Hansen IC, Batcher B, Barker T, Sheffield TJ, Yandava B, Taylor DP, Ranade-Kharkar P, Giauque CC, Eyring KR, Breinholt JW, Miller MR, Carter PR, Gillman JL, Gunn AW, Knowlton KU, Bonkowsky JL, Stefansson K, Nadauld LD, McLeod HL. The Development of an Infrastructure to Facilitate the Use of Whole Genome Sequencing for Population Health. J Pers Med 2022; 12:jpm12111867. [PMID: 36579594 PMCID: PMC9693138 DOI: 10.3390/jpm12111867] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 10/29/2022] [Accepted: 11/04/2022] [Indexed: 11/09/2022] Open
Abstract
The clinical use of genomic analysis has expanded rapidly resulting in an increased availability and utility of genomic information in clinical care. We have developed an infrastructure utilizing informatics tools and clinical processes to facilitate the use of whole genome sequencing data for population health management across the healthcare system. Our resulting framework scaled well to multiple clinical domains in both pediatric and adult care, although there were domain specific challenges that arose. Our infrastructure was complementary to existing clinical processes and well-received by care providers and patients. Informatics solutions were critical to the successful deployment and scaling of this program. Implementation of genomics at the scale of population health utilizes complicated technologies and processes that for many health systems are not supported by current information systems or in existing clinical workflows. To scale such a system requires a substantial clinical framework backed by informatics tools to facilitate the flow and management of data. Our work represents an early model that has been successful in scaling to 29 different genes with associated genetic conditions in four clinical domains. Work is ongoing to optimize informatics tools; and to identify best practices for translation to smaller healthcare systems.
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Affiliation(s)
- Nephi A. Walton
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
- Correspondence:
| | - Brent Hafen
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Sara Graceffo
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Nykole Sutherland
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Melanie Emmerson
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Rachel Palmquist
- Department of Pediatrics, University of Utah, Salt Lake City, UT 84108, USA
- Center for Personalized Medicine, Primary Children’s Hospital, Intermountain Healthcare, Salt Lake City, UT 84113, USA
| | - Christine M. Formea
- Department of Pharmacy, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Maricel Purcell
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Bret Heale
- Humanized Health Consulting, Salt Lake City, UT 84102, USA
| | | | | | - Sumathi I. Rachamadugu
- Department of Bioinformatics and Genomics, Pennsylvania State University, University Park, PA 16802, USA
| | - Thomas N. Person
- John Hopkins Genomics—DNA Diagnostics Laboratory, Department of Genetic Medicine, John Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | | | - G. Bryce Christensen
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Jared M. Evans
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Sharanya Raghunath
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Christopher P. Johnson
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Stacey Knight
- Department of Cardiology, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Viet T. Le
- Department of Cardiology, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Jeffrey L. Anderson
- Department of Cardiology, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Margaret Van Meter
- Department of Medical Oncology, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Teresa Reading
- Department of Surgery, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Derrick S. Haslem
- Department of Cardiology, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Ivy C. Hansen
- School of Medicine, University of Utah, Salt Lake City, UT 84132, USA
| | - Betsey Batcher
- Department of Endocrinology, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Tyler Barker
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Travis J. Sheffield
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Bhaskara Yandava
- Digital Technology Services, Intermountain Healthcare, Salt Lake City, UT 84130, USA
| | - David P. Taylor
- Digital Technology Services, Intermountain Healthcare, Salt Lake City, UT 84130, USA
| | | | - Christopher C. Giauque
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Kenneth R. Eyring
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Jesse W. Breinholt
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Mickey R. Miller
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Payton R. Carter
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Jason L. Gillman
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Andrew W. Gunn
- Center for Personalized Medicine, Primary Children’s Hospital, Intermountain Healthcare, Salt Lake City, UT 84113, USA
| | - Kirk U. Knowlton
- Department of Cardiology, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Joshua L. Bonkowsky
- Department of Pediatrics, University of Utah, Salt Lake City, UT 84108, USA
- Center for Personalized Medicine, Primary Children’s Hospital, Intermountain Healthcare, Salt Lake City, UT 84113, USA
| | | | - Lincoln D. Nadauld
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
| | - Howard L. McLeod
- Intermountain Precision Genomics, Intermountain Healthcare, Salt Lake City, UT 84107, USA
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2
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Szulik MW, Valdez S, Walsh M, Davis K, Bia R, Horiuchi E, O'Very S, Laxman A, Nicolova L, Sheikh H, Hickenlooper S, Miller MR, Wang L, Garcia-Llano J, Tracy C, Drakos SG, Funai K, Chaudhuri D, Boudina S, Franklin S. Abstract P3088: The Histone Lysine Methyltransferase SMYD1a Protects Heart From Ischemic Injury By Regulating OPA1 Mediated Cristae Remodeling And Supercomplex Formation. Circ Res 2022. [DOI: 10.1161/res.131.suppl_1.p3088] [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: 11/16/2022]
Abstract
The histone lysine methyltransferase SMYD1 has been shown to be critical for embryonic cardiac development and in maintaining cardiomyocyte homeostasis in adult mice. Subsequently, we reported that loss of
Smyd1
in the adult mouse myocardium leads to progressive cardiac hypertrophy and heart failure, which is accompanied with downregulation of mitochondrial proteins involved in oxidative phosphorylation, including
Ppargc1a
, and reduction of mitochondrial respiration capacity. To build upon these results and evaluate if SMYD1a can attenuate disease-induced remodeling in an animal model, we generated transgenic mice which inducibly express SMYD1a (the human ortholog) in cardiomyocytes and subjected them to permanent occlusion (PO) of the LAD. This lead to >50% reduction in infarct size and preserved cardiac function, as compared to littermate controls. Additionally, we demonstrated that under physiological conditions SMYD1a maintains metabolic homeostasis by regulating expression of
Ppargc1a
and its downstream targets, including components of the electron transport chain. Our molecular analysis shows that observed protection from ischemic injury results from enhanced mitochondrial respiration through Complex I and II as well as increased ATP production. This is associated with increased mitochondria cristae, and formation and stabilization of respiratory chain supercomplexes within the cristae. These changes in cristae structure occur concomitant with enhanced OPA1 expression, a major regulator of mitochondrial fusion and cristae morphology. Through this work we have established that OPA1 is a novel, functionally important downstream target of SMYD1a by which cardiomyocytes upregulate energy efficiency, protecting them from ischemic injury. These results also highlight SMYD1a as the only known epigenetic regulator of cristae morphology and provide broad implications for understanding the epigenetic mechanisms driving cardiac metabolism. Ultimately this work has identified a novel signaling pathway by which cardiomyocytes regulate energy efficiency, protecting them from ischemic injury.
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Affiliation(s)
| | | | | | | | - Ryan Bia
- Univ of Utah, Salt Lake City, UT
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3
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Adab P, Fitzmaurice DA, Dickens AP, Ayres JG, Buni H, Cooper BG, Daley AJ, Enocson A, Greenfield S, Jolly K, Jowett S, Kalirai K, Marsh JL, Miller MR, Riley RD, Siebert WS, Stockley RA, Turner AM, Cheng KK, Jordan RE. Cohort Profile: The Birmingham Chronic Obstructive Pulmonary Disease (COPD) Cohort Study. Int J Epidemiol 2018; 46:23. [PMID: 27378796 DOI: 10.1093/ije/dyv350] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/04/2015] [Indexed: 11/12/2022] Open
Affiliation(s)
- P Adab
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - D A Fitzmaurice
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - A P Dickens
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - J G Ayres
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - H Buni
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - B G Cooper
- Lung Function & Sleep, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - A J Daley
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - A Enocson
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - S Greenfield
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - K Jolly
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - S Jowett
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - K Kalirai
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - J L Marsh
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - M R Miller
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - R D Riley
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - W S Siebert
- Business School, University of Birmingham, Birmingham, UK
| | - R A Stockley
- Queen Elizabeth Hospital Research Laboratories, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - A M Turner
- School of Inflammation & Aging, University of Birmingham, UK
| | - K K Cheng
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - R E Jordan
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
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4
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Yang X, Jia X, Dong W, Wu S, Miller MR, Hu D, Li H, Pan L, Deng F, Guo X. Cardiovascular benefits of reducing personal exposure to traffic-related noise and particulate air pollution: A randomized crossover study in the Beijing subway system. Indoor Air 2018; 28:777-786. [PMID: 29896813 DOI: 10.1111/ina.12485] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Accepted: 06/08/2018] [Indexed: 05/06/2023]
Abstract
To assess the cardiovascular benefits of protecting against particulate air pollution and noise, we conducted a randomized crossover study with 40 young healthy college students from March to May 2017 in the underground subway, Beijing. Participants each received 4 treatments (no intervention phase [NIP], respirator intervention phase [RIP], headphone intervention phase [HIP], respirator plus headphone intervention phase [RHIP]) in a randomized order during 4 different study periods with 2-week washout intervals. We measured personal exposure to particulate matter (PM), noise and electrocardiogram (ECG) parameters (heart rate variability (HRV), heart rate (HR) and ST segment changes), ambulatory blood pressure (BP) continuously for 4 hours to investigate the cardiovascular effects. Compared with NIP, most of the HRV parameters increased, especially high frequency (HF) [21.1% (95% CI: 15.7%, 26.9%), 18.2% (95% CI: 12.8%, 23.9%), and 35.5% (95% CI: 29.3%, 42.0%) in RIP, HIP, and RHIP, respectively], whereas ST segment elevation and HR decreased for all 3 modes of interventions. However, no significant differences were observed in BP among the 4 treatments. In summary, short-term wearing of a respirator and/or headphone may be an effective way to minimize cardiovascular risk induced by air pollution in the subway by improving autonomic nervous function.
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Affiliation(s)
- X Yang
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, China
| | - X Jia
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, China
| | - W Dong
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, China
| | - S Wu
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, China
| | - M R Miller
- University/BHF Centre for Cardiovascular Science, Queens Medical Research Institute, The University of Edinburgh, Edinburgh, UK
| | - D Hu
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, China
| | - H Li
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, China
| | - L Pan
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, China
| | - F Deng
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, China
| | - X Guo
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, China
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5
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Dong W, Pan L, Li H, Miller MR, Loh M, Wu S, Xu J, Yang X, Shan J, Chen Y, Deng F, Guo X. Association of size-fractionated indoor particulate matter and black carbon with heart rate variability in healthy elderly women in Beijing. Indoor Air 2018; 28:373-382. [PMID: 29315830 DOI: 10.1111/ina.12449] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 12/22/2017] [Indexed: 05/09/2023]
Abstract
Associations between size-fractionated indoor particulate matter (PM) and black carbon (BC) and heart rate variability (HRV) and heart rate (HR) in elderly women remain unclear. Twenty-nine healthy elderly women were measured for 24-hour HRV/HR indices. Real-time size-fractionated indoor PM and BC were monitored on the same day and on the preceding day. Mixed-effects models were applied to investigate the associations between pollutants and HRV/HR indices. Increases in size-fractionated indoor PM were significantly associated with declines in power in the high-frequency band (HF), power in the low-frequency band (LF), and standard deviation of all NN intervals (SDNN). The largest decline in HF was 19% at 5-minute moving average for an interquartile range (IQR) increase (24 μg/m3 ) in PM0.5 . The results showed that smaller particles could lead to greater reductions in HRV indices. The reported associations were modified by body mass index (BMI): Declines in HF at 5-minute average for an IQR increase in PM0.5 were 34.5% and 1.0% for overweight (BMI ≥25 kg/m2 ) and normal-weight (BMI <25 kg/m2 ) participants, respectively. Moreover, negative associations between BC and HRV indices were found to be significant in overweight participants. Increases in size-fractionated indoor PM and BC were associated with compromised cardiac autonomic function in healthy elderly women, especially overweight ones.
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Affiliation(s)
- W Dong
- Department of Occupational and Environmental Health Sciences, Peking University, School of Public Health, Beijing, China
| | - L Pan
- Department of Occupational and Environmental Health Sciences, Peking University, School of Public Health, Beijing, China
| | - H Li
- Department of Occupational and Environmental Health Sciences, Peking University, School of Public Health, Beijing, China
| | - M R Miller
- University/BHF Centre for Cardiovascular Science, Queens Medical Research Institute, The University of Edinburgh, Edinburgh, UK
| | - M Loh
- Institute of Occupational Medicine, Edinburgh, UK
| | - S Wu
- Department of Occupational and Environmental Health Sciences, Peking University, School of Public Health, Beijing, China
| | - J Xu
- Department of Occupational and Environmental Health Sciences, Peking University, School of Public Health, Beijing, China
| | - X Yang
- Department of Occupational and Environmental Health Sciences, Peking University, School of Public Health, Beijing, China
| | - J Shan
- Department of Occupational and Environmental Health Sciences, Peking University, School of Public Health, Beijing, China
| | - Y Chen
- Respiratory Department, Peking University Third Hospital, Beijing, China
| | - F Deng
- Department of Occupational and Environmental Health Sciences, Peking University, School of Public Health, Beijing, China
| | - X Guo
- Department of Occupational and Environmental Health Sciences, Peking University, School of Public Health, Beijing, China
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6
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Luzuriaga-Neira A, Villacís-Rivas G, Cueva-Castillo F, Escudero-Sánchez G, Ulloa-Nuñez A, Rubilar-Quezada M, Monteiro R, Miller MR, Beja-Pereira A. On the origins and genetic diversity of South American chickens: one step closer. Anim Genet 2017; 48:353-357. [PMID: 28094447 DOI: 10.1111/age.12537] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/08/2016] [Indexed: 11/27/2022]
Abstract
Local chicken populations are a major source of food in the rural areas of South America. However, very little is known about their genetic composition and diversity. Here, we analyzed five populations from South America to investigate their maternal genetic origin and diversity, hoping to mitigate the lack of information on local chicken populations from this region. We also included three populations of chicken from the Iberian Peninsula and one from Easter Island, which are potential sources of the first chickens introduced in South America. The obtained sequencing data from South American chickens indicate the presence of four haplogroups (A, B, E and D) that can be further subdivided into nine sub-haplogroups. Of these, four (B1, D1a, E1a(b), E1b) were absent from local Iberian Peninsula chickens and one (D1a) was present only on Easter Island. The presence of the sub-haplogroups A1a(b) and E1a(b) in South America, previously only observed in Eastern Asia, and the significant population differentiation between Iberian Peninsula and South American populations, suggest a second maternal source of the extant genetic pool in South American chickens.
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Affiliation(s)
- A Luzuriaga-Neira
- Centro de Investigação em Biodiversidade e Recursos Genéticos (CIBIO-InBIO), Universidade do Porto, Campus Agrário de Vairão, Rua Padre Armando Quintas 7, 4485-661, Vairão, Portugal
| | - G Villacís-Rivas
- Centro de Biotecnología, Universidad Nacional de Loja, Pio Jaramillo Alvarado s/n sector La Argelia, 1101, Loja, Ecuador
| | - F Cueva-Castillo
- Centro de Biotecnología, Universidad Nacional de Loja, Pio Jaramillo Alvarado s/n sector La Argelia, 1101, Loja, Ecuador
| | - G Escudero-Sánchez
- Universidad Nacional de Loja, Pio Jaramillo Alvarado s/n sector La Argelia, 1101, Loja, Ecuador
| | - A Ulloa-Nuñez
- Facultad de Ciencias Veterinarias, Universidad de Concepción, Av. Vicente Mendez 595, Chillán, Chile
| | - M Rubilar-Quezada
- Facultad de Ciencias Veterinarias, Universidad de Concepción, Av. Vicente Mendez 595, Chillán, Chile
| | - R Monteiro
- Centro de Investigação em Biodiversidade e Recursos Genéticos (CIBIO-InBIO), Universidade do Porto, Campus Agrário de Vairão, Rua Padre Armando Quintas 7, 4485-661, Vairão, Portugal
| | - M R Miller
- Department of Animal Science, University of California, Davis, CA, 95616, USA
| | - A Beja-Pereira
- Centro de Investigação em Biodiversidade e Recursos Genéticos (CIBIO-InBIO), Universidade do Porto, Campus Agrário de Vairão, Rua Padre Armando Quintas 7, 4485-661, Vairão, Portugal.,Department of Biology, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre S/N, Porto, Portugal
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7
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Agustin E, Asare Okai PN, Khan I, Miller MR, Wang R, Sheng J, Royzen M. A fast click-slow release strategy towards the HPLC-free synthesis of RNA. Chem Commun (Camb) 2016; 52:1405-8. [PMID: 26619912 DOI: 10.1039/c5cc05392g] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [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]
Abstract
A general strategy for purification of oligonucleotides synthesized by solid phase synthesis is described. It is based on a recently developed concept involving a bio-orthogonal inverse electron demand Diels-Alder reaction between trans-cyclooctene and tetrazine, termed 'click-to-release'. The strategy has been applied towards the synthesis and purification of a model hairpin RNA strand, as well as a 34 nt long aptamer.
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Affiliation(s)
- E Agustin
- Department of Chemistry, SUNY, University at Albany, 1400 Washington Avenue, Albany, NY 1222, USA.
| | - P N Asare Okai
- Department of Chemistry, SUNY, University at Albany, 1400 Washington Avenue, Albany, NY 1222, USA.
| | - I Khan
- Department of Chemistry, SUNY, University at Albany, 1400 Washington Avenue, Albany, NY 1222, USA.
| | - M R Miller
- Department of Chemistry, SUNY, University at Albany, 1400 Washington Avenue, Albany, NY 1222, USA.
| | - R Wang
- Department of Chemistry, SUNY, University at Albany, 1400 Washington Avenue, Albany, NY 1222, USA.
| | - J Sheng
- Department of Chemistry, SUNY, University at Albany, 1400 Washington Avenue, Albany, NY 1222, USA.
| | - M Royzen
- Department of Chemistry, SUNY, University at Albany, 1400 Washington Avenue, Albany, NY 1222, USA.
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8
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Franklin S, Kimball T, Rasmussen TL, Rosa-Garrido M, Chen H, Tran T, Miller MR, Gray R, Jiang S, Ren S, Wang Y, Tucker HO, Vondriska TM. The chromatin-binding protein Smyd1 restricts adult mammalian heart growth. Am J Physiol Heart Circ Physiol 2016; 311:H1234-H1247. [PMID: 27663768 PMCID: PMC5130490 DOI: 10.1152/ajpheart.00235.2016] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [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: 03/14/2016] [Accepted: 08/16/2016] [Indexed: 11/22/2022]
Abstract
All terminally differentiated organs face two challenges, maintaining their cellular identity and restricting organ size. The molecular mechanisms responsible for these decisions are of critical importance to organismal development, and perturbations in their normal balance can lead to disease. A hallmark of heart failure, a condition affecting millions of people worldwide, is hypertrophic growth of cardiomyocytes. The various forms of heart failure in human and animal models share conserved transcriptome remodeling events that lead to expression of genes normally silenced in the healthy adult heart. However, the chromatin remodeling events that maintain cell and organ size are incompletely understood; insights into these mechanisms could provide new targets for heart failure therapy. Using a quantitative proteomics approach to identify muscle-specific chromatin regulators in a mouse model of hypertrophy and heart failure, we identified upregulation of the histone methyltransferase Smyd1 during disease. Inducible loss-of-function studies in vivo demonstrate that Smyd1 is responsible for restricting growth in the adult heart, with its absence leading to cellular hypertrophy, organ remodeling, and fulminate heart failure. Molecular studies reveal Smyd1 to be a muscle-specific regulator of gene expression and indicate that Smyd1 modulates expression of gene isoforms whose expression is associated with cardiac pathology. Importantly, activation of Smyd1 can prevent pathological cell growth. These findings have basic implications for our understanding of cardiac pathologies and open new avenues to the treatment of cardiac hypertrophy and failure by modulating Smyd1.
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Affiliation(s)
- Sarah Franklin
- Department of Internal Medicine, Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, Utah; and
| | - Todd Kimball
- Departments of Anesthesiology & Perioperative Medicine, Medicine (Cardiology) and Physiology, David Geffen School of Medicine, University of California, Los Angeles, California
| | - Tara L Rasmussen
- Department of Molecular Genetics and the Institute for Cellular and Molecular Biology, University of Texas at Austin, Texas
| | - Manuel Rosa-Garrido
- Departments of Anesthesiology & Perioperative Medicine, Medicine (Cardiology) and Physiology, David Geffen School of Medicine, University of California, Los Angeles, California
| | - Haodong Chen
- Departments of Anesthesiology & Perioperative Medicine, Medicine (Cardiology) and Physiology, David Geffen School of Medicine, University of California, Los Angeles, California
| | - Tam Tran
- Departments of Anesthesiology & Perioperative Medicine, Medicine (Cardiology) and Physiology, David Geffen School of Medicine, University of California, Los Angeles, California
| | - Mickey R Miller
- Department of Internal Medicine, Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, Utah; and
| | - Ricardo Gray
- Departments of Anesthesiology & Perioperative Medicine, Medicine (Cardiology) and Physiology, David Geffen School of Medicine, University of California, Los Angeles, California
| | - Shanxi Jiang
- Departments of Anesthesiology & Perioperative Medicine, Medicine (Cardiology) and Physiology, David Geffen School of Medicine, University of California, Los Angeles, California
| | - Shuxun Ren
- Departments of Anesthesiology & Perioperative Medicine, Medicine (Cardiology) and Physiology, David Geffen School of Medicine, University of California, Los Angeles, California
| | - Yibin Wang
- Departments of Anesthesiology & Perioperative Medicine, Medicine (Cardiology) and Physiology, David Geffen School of Medicine, University of California, Los Angeles, California
| | - Haley O Tucker
- Department of Molecular Genetics and the Institute for Cellular and Molecular Biology, University of Texas at Austin, Texas
| | - Thomas M Vondriska
- Departments of Anesthesiology & Perioperative Medicine, Medicine (Cardiology) and Physiology, David Geffen School of Medicine, University of California, Los Angeles, California
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9
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Kurita D, Miller MR, Muto A, Buskirk AR, Himeno H. Rejection of tmRNA·SmpB after GTP hydrolysis by EF-Tu on ribosomes stalled on intact mRNA. RNA 2014; 20:1706-1714. [PMID: 25246654 PMCID: PMC4201823 DOI: 10.1261/rna.045773.114] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Accepted: 07/18/2014] [Indexed: 06/03/2023]
Abstract
Messenger RNAs lacking a stop codon trap ribosomes at their 3' ends, depleting the pool of ribosomes available for protein synthesis. In bacteria, a remarkable quality control system rescues and recycles stalled ribosomes in a process known as trans-translation. Acting as a tRNA, transfer-messenger RNA (tmRNA) is aminoacylated, delivered by EF-Tu to the ribosomal A site, and accepts the nascent polypeptide. Translation then resumes on a reading frame within tmRNA, encoding a short peptide tag that targets the nascent peptide for degradation by proteases. One unsolved issue in trans-translation is how tmRNA and its protein partner SmpB preferentially recognize stalled ribosomes and not actively translating ones. Here, we examine the effect of the length of the 3' extension of mRNA on each step of trans-translation by pre-steady-state kinetic methods and fluorescence polarization binding assays. Unexpectedly, EF-Tu activation and GTP hydrolysis occur rapidly regardless of the length of the mRNA, although the peptidyl transfer to tmRNA decreases as the mRNA 3' extension increases and the tmRNA·SmpB binds less tightly to the ribosome with an mRNA having a long 3' extension. From these results, we conclude that the tmRNA·SmpB complex dissociates during accommodation due to competition between the downstream mRNA and the C-terminal tail for the mRNA channel. Rejection of the tmRNA·SmpB complex during accommodation is reminiscent of the rejection of near-cognate tRNA from the ribosome in canonical translation.
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Affiliation(s)
- Daisuke Kurita
- Department of Biochemistry and Molecular Biology, Faculty of Agriculture and Life Science, Hirosaki University, Hirosaki 036-8561, Japan
| | - Mickey R Miller
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
| | - Akira Muto
- Department of Biochemistry and Molecular Biology, Faculty of Agriculture and Life Science, Hirosaki University, Hirosaki 036-8561, Japan
| | - Allen R Buskirk
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
| | - Hyouta Himeno
- Department of Biochemistry and Molecular Biology, Faculty of Agriculture and Life Science, Hirosaki University, Hirosaki 036-8561, Japan
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Palti Y, Gao G, Liu S, Kent MP, Lien S, Miller MR, Rexroad CE, Moen T. The development and characterization of a 57K single nucleotide polymorphism array for rainbow trout. Mol Ecol Resour 2014; 15:662-72. [PMID: 25294387 DOI: 10.1111/1755-0998.12337] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2014] [Revised: 09/23/2014] [Accepted: 09/26/2014] [Indexed: 11/30/2022]
Abstract
In this study, we describe the development and characterization of the first high-density single nucleotide polymorphism (SNP) genotyping array for rainbow trout. The SNP array is publically available from a commercial vendor (Affymetrix). The SNP genotyping quality was high, and validation rate was close to 90%. This is comparable to other farm animals and is much higher than previous smaller scale SNP validation studies in rainbow trout. High quality and integrity of the genotypes are evident from sample reproducibility and from nearly 100% agreement in genotyping results from other methods. The array is very useful for rainbow trout aquaculture populations with more than 40 900 polymorphic markers per population. For wild populations that were confounded by a smaller sample size, the number of polymorphic markers was between 10 577 and 24 330. Comparison between genotypes from individual populations suggests good potential for identifying candidate markers for populations' traceability. Linkage analysis and mapping of the SNPs to the reference genome assembly provide strong evidence for a wide distribution throughout the genome with good representation in all 29 chromosomes. A total of 68% of the genome scaffolds and contigs were anchored through linkage analysis using the SNP array genotypes, including ~20% of the genome assembly that has not been previously anchored to chromosomes.
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Affiliation(s)
- Y Palti
- National Center for Cool and Cold Water Aquaculture, ARS-USDA, 11861 Leetown Road, Kearneysville, WV, 25430, USA
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11
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Abstract
In bacteria, transfer-messenger RNA (tmRNA) and SmpB comprise the most common and effective system for rescuing stalled ribosomes. Ribosomes stall on mRNA transcripts lacking stop codons and are rescued as the defective mRNA is swapped for the tmRNA template in a process known as trans-translation. The tmRNA–SmpB complex is recruited to the ribosome independent of a codon–anticodon interaction. Given that the ribosome uses robust discriminatory mechanisms to select against non-cognate tRNAs during canonical decoding, it has been hard to explain how this can happen. Recent structural and biochemical studies show that SmpB licenses tmRNA entry through its interactions with the decoding center and mRNA channel. In particular, the C-terminal tail of SmpB promotes both EFTu activation and accommodation of tmRNA, the former through interactions with 16S rRNA nucleotide G530 and the latter through interactions with the mRNA channel downstream of the A site. Here we present a detailed model of the earliest steps in trans-translation, and in light of these mechanistic considerations, revisit the question of how tmRNA preferentially reacts with stalled, non-translating ribosomes.
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Affiliation(s)
- Mickey R Miller
- Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT USA
| | - Allen R Buskirk
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD USA
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12
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Abstract
In bacteria, ribosomes stalled on truncated mRNAs are rescued by transfer-messenger RNA (tmRNA) and its protein partner SmpB. Acting like tRNA, the aminoacyl-tmRNA/SmpB complex is delivered to the ribosomal A site by EF-Tu and accepts the transfer of the nascent polypeptide. Although SmpB binding within the decoding center is clearly critical for licensing tmRNA entry into the ribosome, it is not known how activation of EF-Tu occurs in the absence of a codon-anticodon interaction. A recent crystal structure revealed that SmpB residue His136 stacks on 16S rRNA nucleotide G530, a critical player in the canonical decoding mechanism. Here we use pre-steady-state kinetic methods to probe the role of this interaction in ribosome rescue. We find that although mutation of His136 does not reduce SmpB's affinity for the ribosomal A-site, it dramatically reduces the rate of GTP hydrolysis by EF-Tu. Surprisingly, the same mutation has little effect on the apparent rate of peptide-bond formation, suggesting that release of EF-Tu from the tmRNA/SmpB complex on the ribosome may occur prior to GTP hydrolysis. Consistent with this idea, we find that peptidyl transfer to tmRNA is relatively insensitive to the antibiotic kirromycin. Taken together, our studies provide a model for the initial stages of ribosomal rescue by tmRNA.
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13
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Ward HM, Cooper BG, Miller MR. P37 Which Bronchodilator Reversibility Definition Best Avoids Bias. Thorax 2012. [DOI: 10.1136/thoraxjnl-2012-202678.178] [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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14
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Miller MR, Liu Z, Cazier DJ, Gebhard GM, Herron SR, Zaher HS, Green R, Buskirk AR. The role of SmpB and the ribosomal decoding center in licensing tmRNA entry into stalled ribosomes. RNA 2011; 17:1727-1736. [PMID: 21795410 PMCID: PMC3162337 DOI: 10.1261/rna.2821711] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Accepted: 06/24/2011] [Indexed: 05/31/2023]
Abstract
In bacteria, stalled ribosomes are recycled by a hybrid transfer-messenger RNA (tmRNA). Like tRNA, tmRNA is aminoacylated with alanine and is delivered to the ribosome by EF-Tu, where it reacts with the growing polypeptide chain. tmRNA entry into stalled ribosomes poses a challenge to our understanding of ribosome function because it occurs in the absence of a codon-anticodon interaction. Instead, tmRNA entry is licensed by the binding of its protein partner, SmpB, to the ribosomal decoding center. We analyzed a series of SmpB mutants and found that its C-terminal tail is essential for tmRNA accommodation but not for EF-Tu activation. We obtained evidence that the tail likely functions as a helix on the ribosome to promote accommodation and identified key residues in the tail essential for this step. In addition, our mutational analysis points to a role for the conserved K(131)GKK tail residues in trans-translation after peptidyl transfer to tmRNA, presumably EF-G-mediated translocation or translation of the tmRNA template. Surprisingly, analysis of A1492, A1493, and G530 mutants reveals that while these ribosomal nucleotides are essential for normal tRNA selection, they play little to no role in peptidyl transfer to tmRNA. These studies clarify how SmpB interacts with the ribosomal decoding center to license tmRNA entry into stalled ribosomes.
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Affiliation(s)
- Mickey R. Miller
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
| | - Zhu Liu
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
| | - DeAnna J. Cazier
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
| | - Grant M. Gebhard
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
| | - Steven R. Herron
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
| | - Hani S. Zaher
- Howard Hughes Medical Institute, Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | - Rachel Green
- Howard Hughes Medical Institute, Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | - Allen R. Buskirk
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
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Allen-Petersen BL, Miller MR, Neville MC, Anderson SM, Nakayama KI, Reyland ME. Loss of protein kinase C delta alters mammary gland development and apoptosis. Cell Death Dis 2011; 1:e17. [PMID: 21364618 PMCID: PMC3032509 DOI: 10.1038/cddis.2009.20] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [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] [Indexed: 01/26/2023]
Abstract
As apoptotic pathways are commonly deregulated in breast cancer, exploring how mammary gland cell death is regulated is critical for understanding human disease. We show that primary mammary epithelial cells from protein kinase C delta (PKCδ) −/− mice have a suppressed response to apoptotic agents in vitro. In the mammary gland in vivo, apoptosis is critical for ductal morphogenesis during puberty and involution following lactation. We have explored mammary gland development in the PKCδ −/− mouse during these two critical windows. Branching morphogenesis was altered in 4- to 6-week-old PKCδ −/− mice as indicated by reduced ductal branching; however, apoptosis and proliferation in the terminal end buds was unaltered. Conversely, activation of caspase-3 during involution was delayed in PKCδ −/− mice, but involution proceeded normally. The thymus also undergoes apoptosis in response to physiological signals. A dramatic suppression of caspase-3 activation was observed in the thymus of PKCδ −/− mice treated with irradiation, but not mice treated with dexamethasone, suggesting that there are both target- and tissue-dependent differences in the execution of apoptotic pathways in vivo. These findings highlight a role for PKCδ in both apoptotic and nonapoptotic processes in the mammary gland and underscore the redundancy of apoptotic pathways in vivo.
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Affiliation(s)
- B L Allen-Petersen
- Stem Cells and Development, School of Medicine, University of Colorado Denver, Aurora, CO 80045, USA
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Quanjer PH, Enright PL, Miller MR, Stocks J, Ruppel G, Swanney MP, Crapo RO, Pedersen OF, Falaschetti E, Schouten JP, Jensen RL. The need to change the method for defining mild airway obstruction. Eur Respir J 2011; 37:720-2. [PMID: 21357929 DOI: 10.1183/09031936.00135110] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Stavroudis TA, Shore AD, Morlock L, Hicks RW, Bundy D, Miller MR. NICU medication errors: identifying a risk profile for medication errors in the neonatal intensive care unit. J Perinatol 2010; 30:459-68. [PMID: 20043010 DOI: 10.1038/jp.2009.186] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [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: 01/17/2023]
Abstract
OBJECTIVE To identify a risk profile for harmful medication errors in the neonatal intensive care unit (NICU). STUDY DESIGN A retrospective cross-sectional study on NICU medication error reports submitted to MEDMARX between 1 January 1999, and 31 December 2005. The Rao-Scott modified chi(2) test was used for analysis. RESULT 6749 NICU medication error reports were submitted by 163 health-care facilities. Administering errors accounted for approximately one half of errors, and human factors were the most frequently cited cause of error. Patient age was not associated with an increased likelihood of an error being harmful (P=0.11). Error reports involving Institute for Safe Medication Practices (ISMP) High-Alert Medications, occurring in the prescribing phase of medication processing, or involving equipment/delivery device failures were more likely to be harmful (P< or =0.05). CONCLUSION Risk factors for harmful medication error reports include use of ISMP High-Alert Medications, the prescribing phase of the medication use process, and failure of equipment/delivery devices.
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Affiliation(s)
- T A Stavroudis
- Eudowood Neonatal Pulmonary Division, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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Langrish JP, Li X, Wang S, Lee MMY, Barnes GD, Ge GL, Miller MR, Cassee FR, Boon NA, Donaldson K, Li J, Mills NL, Jiang L, Newby DE. 051 Reducing particulate air pollution exposure in patients with coronary heart disease: improved cardiovascular health. Heart 2010. [DOI: 10.1136/hrt.2010.195958.25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Miller MR, Pedersen OF, Pellegrino R, Brusasco V. Debating the definition of airflow obstruction: time to move on? Eur Respir J 2010; 34:527-8. [PMID: 19720804 DOI: 10.1183/09031936.00103309] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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20
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Lam KBH, Jordan RE, Jiang CQ, Thomas GN, Miller MR, Zhang WS, Lam TH, Cheng KK, Adab P. Airflow obstruction and metabolic syndrome: the Guangzhou Biobank Cohort Study. Eur Respir J 2009; 35:317-23. [PMID: 19574332 DOI: 10.1183/09031936.00024709] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
There is some evidence that chronic obstructive pulmonary disease (COPD) and metabolic syndrome may be related, perhaps through systemic inflammation, which is common to both. However, the association between the two conditions has not yet been clearly shown. The present study involved 7,358 adults aged > or =50 yrs from a population-based survey who underwent spirometry, a structured interview and measurement of fasting metabolic marker levels. Airflow obstruction (forced expiratory volume in 1 s/forced vital capacity ratio of less than the lower limit of normal) was present in 6.7%, and the International Diabetes Federation metabolic syndrome criteria were met by 20.0%. The risk of metabolic syndrome was higher in those with airflow obstruction than in those without (odds ratio (OR) 1.47; 95% confidence interval (CI) 1.12-1.92), after controlling for potential confounders. Of the five components of metabolic syndrome, only central obesity was significantly associated with airflow obstruction (OR 1.43; 95% CI 1.09-1.88) after adjusting for body mass index. A similar association was observed in both never and current smokers. In this Chinese sample, airflow obstruction was associated with metabolic syndrome, and, in particular, its central obesity component. This may help explain the increased risk of cardiovascular diseases in COPD, and so could guide future clinical practice.
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Affiliation(s)
- K-B H Lam
- Guangzhou Number 12 People's Hospital, No. 1 Tianqiang Lu, Huangpu Da Dao Xi, Guangzhou 510620, People's Republic of China
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Miller MR, Beck J. Innervation of a lizard auditory organ having gap junctions between most hair cells: a serial transmission electron microscopy study. J Comp Neurol 2009; 293:223-35. [PMID: 19189713 DOI: 10.1002/cne.902930206] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Two apical unidirectional and 16 basal bidirectional papillar hair cells of the yucca night lizard, Xantusia vigilis, were serially sectioned for transmission electron microscopy (TEM) to determine the pattern of hair cell innervation. The 16 bidirectional hair cells (central group) were sectioned across the entire width of the papilla and consisted of four complete hair cells in each of the first three rows and the upper (or neural) half of the four hair cells in the fourth or last row. Both hair cell types were nonexclusively innervated, i.e., each afferent nerve fiber innervated two or more hair cells. The apical unidirectional hair cells were innervated by six or seven different afferent nerve fibers and five or six efferent fibers. The afferent nerve fibers made an average of 52.5 synapses/hair cell. In the central group of 16 bidirectional hair cells, 25 different afferent nerve fibers innervated an average of 4.5 hair cells. The average number of hair cells innervated by the eight afferent nerve fibers limited to the central group was 5.4. An unusual finding was the presence of gap junctions directly interconnecting more than half the hair cells in both papillar segments. In the bidirectional hair cell region, it was possible to count the number of gap junctions between 24 contiguous hair cells. The average number of gap junctions was four per hair cell, and all bidirectional hair cells were either directly or indirectly interconnected by gap junctions. The possible functions of a nonexclusive type of hair cell innervation and the presence of large numbers of gap junctions are discussed.
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Affiliation(s)
- M R Miller
- Department of Anatomy, University of California, San Francisco, California 94143, USA
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Swanney MP, Ruppel G, Enright PL, Pedersen OF, Crapo RO, Miller MR, Jensen RL, Falaschetti E, Schouten JP, Hankinson JL, Stocks J, Quanjer PH. Using the lower limit of normal for the FEV1/FVC ratio reduces the misclassification of airway obstruction. Thorax 2008; 63:1046-51. [PMID: 18786983 DOI: 10.1136/thx.2008.098483] [Citation(s) in RCA: 329] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIM The prevalence of airway obstruction varies widely with the definition used. OBJECTIVES To study differences in the prevalence of airway obstruction when applying four international guidelines to three population samples using four regression equations. METHODS We collected predicted values for forced expiratory volume in 1 s/forced vital capacity (FEV(1)/FVC) and its lower limit of normal (LLN) from the literature. FEV(1)/FVC from 40 646 adults (including 13 136 asymptomatic never smokers) aged 17-90+years were available from American, English and Dutch population based surveys. The prevalence of airway obstruction was determined by the LLN for FEV(1)/FVC, and by using the Global Initiative for Chronic Obstructive Lung Disease (GOLD), American Thoracic Society/European Respiratory Society (ATS/ERS) or British Thoracic Society (BTS) guidelines, initially in the healthy subgroup and then in the entire population. RESULTS The LLN for FEV(1)/FVC varied between prediction equations (57 available for men and 55 for women), and demonstrated marked negative age dependency. Median age at which the LLN fell below 0.70 in healthy subjects was 42 and 48 years in men and women, respectively. When applying the reference equations (Health Survey for England 1995-1996, National Health and Nutrition Examination Survey (NHANES) III, European Community for Coal and Steel (ECCS)/ERS and a Dutch population study) to the selected population samples, the prevalence of airway obstruction in healthy never smokers aged over 60 years varied for each guideline: 17-45% of men and 7-26% of women for GOLD; 0-18% of men and 0-16% of women for ATS/ERS; and 0-9% of men and 0-11% of women for BTS. GOLD guidelines caused false positive rates of up to 60% when applied to entire populations. CONCLUSIONS Airway obstruction should be defined by FEV(1)/FVC and FEV(1) being below the LLN using appropriate reference equations.
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Affiliation(s)
- M P Swanney
- Respiratory Physiology Laboratory, Christchurch Hospital, Private Bag 4710, Christchurch 8140, New Zealand.
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Miller MR, Healey DW, Robison SG, Dewey JD, Buskirk AR. The role of upstream sequences in selecting the reading frame on tmRNA. BMC Biol 2008; 6:29. [PMID: 18590561 PMCID: PMC2481249 DOI: 10.1186/1741-7007-6-29] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [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: 04/16/2008] [Accepted: 06/30/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND tmRNA acts first as a tRNA and then as an mRNA to rescue stalled ribosomes in eubacteria. Two unanswered questions about tmRNA function remain: how does tmRNA, lacking an anticodon, bypass the decoding machinery and enter the ribosome? Secondly, how does the ribosome choose the proper codon to resume translation on tmRNA? According to the -1 triplet hypothesis, the answer to both questions lies in the unique properties of the three nucleotides upstream of the first tmRNA codon. These nucleotides assume an A-form conformation that mimics the codon-anticodon interaction, leading to recognition by the decoding center and choice of the reading frame. The -1 triplet hypothesis is important because it is the most credible model in which direct binding and recognition by the ribosome sets the reading frame on tmRNA. RESULTS Conformational analysis predicts that 18 triplets cannot form the correct structure to function as the -1 triplet of tmRNA. We tested the tmRNA activity of all possible -1 triplet mutants using a genetic assay in Escherichia coli. While many mutants displayed reduced activity, our findings do not match the predictions of this model. Additional mutagenesis identified sequences further upstream that are required for tmRNA function. An immunoblot assay for translation of the tmRNA tag revealed that certain mutations in U85, A86, and the -1 triplet sequence result in improper selection of the first codon and translation in the wrong frame (-1 or +1) in vivo. CONCLUSION Our findings disprove the -1 triplet hypothesis. The -1 triplet is not required for accommodation of tmRNA into the ribosome, although it plays a minor role in frame selection. Our results strongly disfavor direct ribosomal recognition of the upstream sequence, instead supporting a model in which the binding of a separate ligand to A86 is primarily responsible for frame selection.
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Affiliation(s)
- Mickey R Miller
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA.
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Pellegrino R, Brusasco V, Viegi G, Crapo RO, Burgos F, Casaburi R, Coates A, van der Grinten CPM, Gustafsson P, Hankinson J, Jensen R, Johnson DC, Macintyre N, McKay R, Miller MR, Navajas D, Pedersen OF, Wanger J. Definition of COPD: based on evidence or opinion? Eur Respir J 2008; 31:681-2. [PMID: 18310402 DOI: 10.1183/09031936.00154307] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Yin P, Jiang CQ, Cheng KK, Lam TH, Lam KH, Miller MR, Zhang WS, Thomas GN, Adab P. Passive smoking exposure and risk of COPD among adults in China: the Guangzhou Biobank Cohort Study. Lancet 2007; 370:751-7. [PMID: 17765524 DOI: 10.1016/s0140-6736(07)61378-6] [Citation(s) in RCA: 189] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
BACKGROUND Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality in China, where the population is also exposed to high levels of passive smoking, yet little information exists on the effects of such exposure on COPD. We examined the relation between passive smoking and COPD and respiratory symptoms in an adult Chinese population. METHODS We used baseline data from the Guangzhou Biobank Cohort Study. Of 20 430 men and women over the age of 50 recruited in 2003-06, 15,379 never smokers (6497 with valid spirometry) were included in this cross-sectional analysis. We measured passive smoking exposure at home and work by two self-reported measures (density and duration of exposure). Diagnosis of COPD was based on spirometry and defined according to the GOLD guidelines. FINDINGS There was an association between risk of COPD and self-reported exposure to passive smoking at home and work (adjusted odds ratio 1.48, 95% CI 1.18-1.85 for high level exposure; equivalent to 40 h a week for more than 5 years). There were significant associations between reported respiratory symptoms and increasing passive smoking exposure (1.16, 1.07-1.25 for any symptom). INTERPRETATION Exposure to passive smoking is associated with an increased prevalence of COPD and respiratory symptoms. If this association is causal, we estimate that 1.9 million excess deaths from COPD among never smokers could be attributable to passive smoking in the current population in China. Our findings provide strong evidence for urgent measures against passive smoking in China.
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Affiliation(s)
- P Yin
- Department of Public Health and Epidemiology, University of Birmingham, UK
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26
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Segal JB, McNamara RL, Miller MR, Powe NR, Goodman SN, Robinson KA, Bass EB. WITHDRAWN: Anticoagulants or antiplatelet therapy for non-rheumatic atrial fibrillation and flutter. Cochrane Database Syst Rev 2007; 2006:CD001938. [PMID: 17636690 PMCID: PMC10759270 DOI: 10.1002/14651858.cd001938.pub2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Atrial fibrillation (AF) carries a high risk of stroke and other thromboembolic events. Appropriate use of drugs to prevent thromboembolism in patients with AF involves comparing the patient's risk of stroke to the risk of hemorrhage from medication use. OBJECTIVES To quantify risk of stroke, major hemorrhage and death from using medications that have been rigorously evaluated for prevention of thromboembolism in AF. SEARCH STRATEGY Articles were identified through the Cochrane Collaboration's CENTRAL database and MEDLINE until December 1999. SELECTION CRITERIA Included Randomized controlled trials of drugs to prevent thromboembolism in adults with non-postoperative AF. Excluded RCTS of patients with rheumatic valvular disease. DATA COLLECTION AND ANALYSIS Data were abstracted by two reviewers. Odds ratios from all qualitatively similar studies were combined, with weighting by study size, to yield aggregate odds ratios for stroke, major hemorrhage, and death for each drug. MAIN RESULTS Fourteen articles were included in this review. Warfarin was more efficacious than placebo for primary stroke prevention {aggregate odds ratio (OR) of stroke=0.30 [95% Confidence Interval (C.I.) 0.19,0.48]}, with moderate evidence of more major bleeding { OR= 1.90 [95% C.I. 0.89,4.04].}. Aspirin was inconclusively more efficacious than placebo for stroke prevention {OR=0.68 [95% C.I. 0.29,1.57]}, with inconclusive evidence regarding more major bleeds {OR=0.81[95% C.I. 0.37,1.78]}. For primary prevention, assuming a baseline risk of 45 strokes per 1000 patient-years, warfarin could prevent 30 strokes at the expense of only 6 additional major bleeds. Aspirin could prevent 17 strokes, without increasing major hemorrhage. In direct comparison, there was moderate evidence for fewer strokes among patients on warfarin than on aspirin {aggregate OR=0.64[95% C.I. 0.43,0.96]}, with only suggestive evidence for more major hemorrhage {OR =1.58 [95% C.I. 0.76,3.27]}. However, in younger patients, with a mean age of 65 years, the absolute reduction in stroke rate with warfarin compared to aspirin was low (5.5 per 1000 person-years) compared to an older group (15 per 1000 person-years). Low-dose warfarin or low-dose warfarin with aspirin was less efficacious for stroke prevention than adjusted-dose warfarin. AUTHORS' CONCLUSIONS The evidence strongly supports warfarin in AF for patients at average or greater risk of stroke, although clearly there is a risk of hemorrhage. Although not definitively supported by the evidence, aspirin may prove to be useful for stroke prevention in sub-groups with a low risk of stroke, with less risk of hemorrhage than with warfarin. Further studies are needed of low- molecular weight heparin and aspirin in lower risk patients.
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Affiliation(s)
- J B Segal
- Johns Hopkins University, General Internal Medicine, 1830 E. Monument St. 8th Floor, Baltimore, Maryland 21205, USA.
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Abstract
During the 1980s, the free radical, nitric oxide (NO), was discovered to be a crucial signalling molecule, with wide-ranging functions in the cardiovascular, nervous and immune systems. Aside from providing a credible explanation for the actions of organic nitrates and sodium nitroprusside that have long been used in the treatment of angina and hypertensive crises respectively, the discovery generated great hopes for new NO-based treatments for a wide variety of ailments. Decades later, however, we are still awaiting novel licensed agents in this arena, despite an enormous research effort to this end. This review explores some of the most promising recent advances in NO donor drug development and addresses the challenges associated with NO as a therapeutic agent.
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Affiliation(s)
- M R Miller
- Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute Edinburgh, UK
| | - I L Megson
- Free Radical Research Facility, Department of Diabetes, UHI Millennium Institute Inverness, UK
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Magro AM, Magro AD, Cunningham C, Miller MR. Down-regulation of vinculin upon MK886-induced apoptosis in LN18 glioblastoma cells. Neoplasma 2007; 54:517-526. [PMID: 17949236 PMCID: PMC4320946] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Glioblastomas are a type of malignant brain tumor and are among the most difficult cancers to treat. One strategy to treat aggressive cancers is the use of drugs that target multiple signaling pathways. MK886 is a drug known to inhibit both 5- lipoxygenase-activating-protein (FLAP) and peroxisome proliferator activated receptor-alpha (PPAR-alpha). The objectives of this study were to investigate the ability of MK886 to induce apoptotic cell death in LN18 glioblastoma cells and to characterize the cell death mechanisms. MK886 induced massive apoptotic LN18 cell death that was manifested by the release of nucleosomes, annexinV binding to phosphatidylserine in the absence of nuclear staining, and changes in the fluorescent intensity of Mito Tracker Deep Red 633 indicating changes in mitochondrial oxidative function and mass. The alteration of the mitochondrial function implied that MK886 induced apoptosis in LN18 cells via a mitochondrial pathway. The broad caspases inhibitor ZVAD-FMK inhibited MK886-induced nucleosome release, but not annexinV binding or MK886-altered mitochondrial function. Real time RT-PCR demonstrated that LN18 cells expressed significant levels of FLAP and PPAR- alpha mRNAs. A low level of arachidonate 5-lipoxygenase (ALOX-5) mRNA was detected, but little, if any, arachidonate 12- lipoxygenase (ALOX-12) mRNA was present. In addition, MK886-induced apoptosis in LN18 cells was accompanied by a decrease in the protein and mRNA levels of vinculin, but not other focal adhesion proteins. In summary, the data presented here indicate that disruption of the actin-vinculin-cell-cytoskeleton matrix of the LN18 glioblastoma is a component of the MK886 induced apoptosis. In addition, MK886 treated LN18 cells could provide one model in which to investigate drugs that target lipoxygenase and PPAR-alpha pathways in the chemotherapeutic treatment of glioblastomas.
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Affiliation(s)
- A M Magro
- Department of Biology, Fairmont University, Fairmont, WV 26554, USA.
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29
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Miller MR, Hankinson J, Brusasco V, Burgos F, Casaburi R, Coates A, Crapo R, Enright P, van der Grinten CPM, Gustafsson P, Jensen R, Johnson DC, MacIntyre N, McKay R, Navajas D, Pedersen OF, Pellegrino R, Viegi G, Wanger J. Standardisation of spirometry. Eur Respir J 2006; 26:319-38. [PMID: 16055882 DOI: 10.1183/09031936.05.00034805] [Citation(s) in RCA: 10738] [Impact Index Per Article: 596.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- M R Miller
- University Hospital Birmingham NHS Trust, Birmingham, UK
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Abstract
BACKGROUND Despite the growing use of error reporting tools, the healthcare industry is inexperienced in receiving, understanding, and analyzing these reports. OBJECTIVE To assess the accuracy and define the epidemiology of medication error reports. DESIGN, SETTING, AND PATIENTS A retrospective cohort study of 581 error reports containing 1010 medication errors reported between July 2001 and January 2003 at a large academic children's institution. MAIN OUTCOME MEASURES Correct classification and types of medication errors. RESULTS Of the 1010 medication errors reviewed, 298 (30%) were prescribing errors, 245 (24%) were dispensing errors, 410 (41%) were administration errors, and 57 (6%) involved medication administration records (MAR). Following expert review, 208 errors (21%) were deleted because they had been inappropriately coded as errors and 97 (10%) were added as they were not initially coded despite having occurred. In addition, 352 medication error reports needed to have the subtype of error reclassified; 207 (59%) of these involved the reporter choosing the non-descript "other" category on the reporting tool (such as "Prescribing other") which was able to be reclassified by expert review. The overall distribution of error type categories did not change significantly with expert review, although only MAR errors were underreported by the reporters. The most common medications were anti-infectives (17%), pain/sedative agents (15%), nutritional agents (11%), gastrointestinal agents (8%), and cardiovascular agents (7%). CONCLUSIONS Despite clear imperfections in the data captured, medication error reporting tools are effective as a means of collecting reliable information on errors rapidly and in real time. Our data suggest that administration errors are at least as common as prescribing errors in children. Further research is needed, not only in the area of computerized physician order entry (CPOE) for children, but also on ways to make the dispensing and administration of medications safer.
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Affiliation(s)
- M R Miller
- Department of Pediatrics and Center for Innovations in Quality Patient Care, The Johns Hopkins University, Baltimore, MD, USA.
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Macintyre N, Crapo RO, Viegi G, Johnson DC, van der Grinten CPM, Brusasco V, Burgos F, Casaburi R, Coates A, Enright P, Gustafsson P, Hankinson J, Jensen R, McKay R, Miller MR, Navajas D, Pedersen OF, Pellegrino R, Wanger J. Standardisation of the single-breath determination of carbon monoxide uptake in the lung. Eur Respir J 2006; 26:720-35. [PMID: 16204605 DOI: 10.1183/09031936.05.00034905] [Citation(s) in RCA: 1561] [Impact Index Per Article: 86.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- N Macintyre
- Duke University Medical Center, Durham, NC, USA
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32
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Abstract
tmRNA rescues stalled ribosomes in eubacteria by forcing the ribosome to abandon its mRNA template and resume translation with tmRNA itself as a template. Pseudoknot 1 (pk1), immediately upstream of this coding region in tmRNA, is a structural element that is considered essential for tmRNA function based on the analysis of pk1 mutants in vitro. pk1 binds near the ribosomal decoding site and may make base-specific contacts with tmRNA ligands. To study pk1 structure and function in vivo, we have developed a genetic selection that ties the life of Escherichia coli cells to tmRNA activity. Mutation of pk1 at 20% per base and selection for tmRNA activity yielded sequences that retain the same pseudoknot fold. In contrast, selection of active mutants from 10(6) completely random sequences identified hairpin structures that functionally replace pk1. Rational design of a hairpin with increased stability using an unrelated sequence yielded a tmRNA mutant with nearly wild-type activity. We conclude that the role of pk1 in tmRNA function is purely structural and that it can be replaced with a variety of hairpin structures. Our results demonstrate that in the study of functional RNAs, the inactivity of a mutant designed to destroy a given structure should not be interpreted as proof that the structure is necessary for RNA function. Such mutations may only destabilize a global fold that could be formed equally well by an entirely different, stable structure.
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Affiliation(s)
- Douglas R Tanner
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA
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33
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Pellegrino R, Viegi G, Brusasco V, Crapo RO, Burgos F, Casaburi R, Coates A, van der Grinten CPM, Gustafsson P, Hankinson J, Jensen R, Johnson DC, MacIntyre N, McKay R, Miller MR, Navajas D, Pedersen OF, Wanger J. Interpretative strategies for lung function tests. Eur Respir J 2006; 26:948-68. [PMID: 16264058 DOI: 10.1183/09031936.05.00035205] [Citation(s) in RCA: 3617] [Impact Index Per Article: 200.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- R Pellegrino
- Internal Medicine, University of Genoa, V.le Benedetto XV, 6, Genova I-16132, Italy
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Wanger J, Clausen JL, Coates A, Pedersen OF, Brusasco V, Burgos F, Casaburi R, Crapo R, Enright P, van der Grinten CPM, Gustafsson P, Hankinson J, Jensen R, Johnson D, Macintyre N, McKay R, Miller MR, Navajas D, Pellegrino R, Viegi G. Standardisation of the measurement of lung volumes. Eur Respir J 2005; 26:511-22. [PMID: 16135736 DOI: 10.1183/09031936.05.00035005] [Citation(s) in RCA: 1806] [Impact Index Per Article: 95.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- J Wanger
- Internal Medicine, University of Genoa, V.le Benedetto XV, 6, I-16132 Genova, Italy
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35
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Miller MR, Crapo R, Hankinson J, Brusasco V, Burgos F, Casaburi R, Coates A, Enright P, van der Grinten CPM, Gustafsson P, Jensen R, Johnson DC, MacIntyre N, McKay R, Navajas D, Pedersen OF, Pellegrino R, Viegi G, Wanger J. General considerations for lung function testing. Eur Respir J 2005; 26:153-61. [PMID: 15994402 DOI: 10.1183/09031936.05.00034505] [Citation(s) in RCA: 1267] [Impact Index Per Article: 66.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- M R Miller
- University Hospital Birmingham NHS Trust, UK
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Miller MR, White A, Boots M. The evolution of host resistance: tolerance and control as distinct strategies. J Theor Biol 2005; 236:198-207. [PMID: 16005309 DOI: 10.1016/j.jtbi.2005.03.005] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2004] [Revised: 03/02/2005] [Accepted: 03/02/2005] [Indexed: 11/23/2022]
Abstract
In response to parasitic infection, hosts may evolve defences that reduce the deleterious effects on survivorship. This may be interpreted as a form of resistance, as long as infected hosts are able to either recover or reproduce. Here we distinguish two important routes to this form of resistance. An infected host may either: (1) tolerate pathogen damage, or (2) control the pathogen by inhibiting its growth. A model is constructed to examine the evolutionary dynamics of tolerance and control to a free-living microparasite, where both forms of resistance are costly in terms of other life-history traits. We do not observe polymorphism of tolerant genotypes. In contrast, the evolution of control may lead to disruptive selection, and ultimately dimorphism of extreme strains. The optimal host genotype also varies with the type of resistance-individuals invest more in tolerance and pay a greater cost. The free-living framework used makes the distinction between tolerance and control explicit but the distinction applies equally to directly transmitted parasites. Due to the evolutionary differences exhibited, it is important to design experiments that distinguish between the two forms of resistance.
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Affiliation(s)
- M R Miller
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, England, UK.
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37
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Miller MR. The PEF data plot: planning to get the message. Thorax 2005; 60:91-2. [PMID: 15681491 PMCID: PMC1747304 DOI: 10.1136/thx.2004.035782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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38
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Miller MR, Okubo K, Roseberry MJ, Webb DJ, Megson IL. Extracellular nitric oxide release mediates soluble guanylate cyclase-independent vasodilator action of spermine NONOate: comparison with other nitric oxide donors in isolated rat femoral arteries. J Cardiovasc Pharmacol 2004; 43:440-51. [PMID: 15076229 DOI: 10.1097/00005344-200403000-00016] [Citation(s) in RCA: 10] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Nitric oxide (NO) and NO donors exhibit actions that are not entirely mediated by soluble guanylate cyclase (sGC). The site of NO release may influence the involvement of sGC-independent effects. Here we use spermine NONOate (SPER/NO) to release NO extracellularly, compared with other NO donors. Isolated rat femoral arteries were perfused luminally and perfusion pressure monitored. Vessels were contracted with phenylephrine (2-14 microM) in the presence of an NO synthase inhibitor (N(omega)-nitro-L-arginine methyl ester; 20 microM). Vasodilator responses to NO donors were assessed before and after perfusion of an sGC inhibitor (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one; ODQ; 20 microM), NO scavengers (hemoglobin; Hb & hydroquinone; HQ), and a superoxide generator (duroquinone; DQ). ODQ (20 microM) abolished the vasodilator responses to glyceryl trinitrate (10(-8) - 10(-3) M), and sodium nitroprusside (10(-8) - 10(-4) M), which release NO intracellularly. ODQ (20 microM) attenuated, but failed to abolish, the vasodilator responses to SPER/NO (10(-6) - 10(-3) M). ODQ abolished responses to S-nitrosoglutathione and S-nitroso-N-valeryl-D-penicillamine (10(-8) - 10(-4) M), but a small residual vasodilatation remained in response to 10(-3) M. In the presence of ODQ, the remaining vasodilatation to SPER/NO was all but abolished by scavengers of extracellular NO (Hb; 10 microM, HQ; 100 microM). Superoxide generation (DQ; 100 microM) also attenuated ODQ-resistant vasodilatation. The data suggest that, in rat femoral arteries, NO donors that are capable of releasing extracellular NO cause vasodilatation that is only partially mediated by sGC. Lack of augmentation of sGC-independent effects by superoxide suggests that they are not mediated by peroxynitrite.
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Affiliation(s)
- M R Miller
- Centre for Cardiovascular Science, Hugh Robson Building, University of Edinburgh, Edinburgh, Scotland, UK
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Kjaergaard SK, Pedersen OF, Miller MR, Rasmussen TR, Hansen JC, Mølhave L. Ozone exposure decreases the effect of a deep inhalation on forced expiratory flow in normal subjects. J Appl Physiol (1985) 2004; 96:1651-7. [PMID: 14688031 DOI: 10.1152/japplphysiol.00507.2003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [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: 11/22/2022] Open
Abstract
Sixteen healthy nonsmoking subjects (7 women), 21-49 yr old, were exposed in a climate chamber to either clean air or 300 parts/billion ozone on 4 days for 5 h each day. Before each exposure, the subjects had been pretreated with either oxidants (fish oil) or antioxidants (multivitamins). The study design was double-blind crossover with randomized allocation to the exposure regime. Full and partial flow-volume curves were recorded in the morning and before and during a histamine provocation at the end of the day. Nasal cavity volume and inflammatory markers in nasal lavage fluid were also measured. Compared with air, ozone exposure decreased peak expiratory flow, forced expiratory volume in 1 s, and forced vital capacity (FVC), with no significant effect from the pretreatment regimens. Ozone decreased the ratio of maximal to partial flow at 40% FVC by 0.08 ± 0.03 (mean ± SE, analysis of variance: P = 0.018) and at 30% FVC by 0.10 ± 0.05 ( P = 0.070). Ozone exposure did not significantly increase bronchial responsiveness, but, after treatment with fish oil, partial flows decreased more than after vitamins during the histamine test, without changing the maximal-to-partial flow ratio. The decreased effect of a deep inhalation after ozone exposure can be explained by changes in airway hysteresis relative to parenchymal hysteresis, due either to ozone-induced airway inflammation or to less deep inspiration after ozone, not significantly influenced by multivitamins or fish oil.
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Affiliation(s)
- S K Kjaergaard
- Department of Environmental and Occupational Medicine, Univ. of Aarhus, DK-8000 Aarhus C, Denmark
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40
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Abstract
Administrative data are readily available, inexpensive, computer readable, and cover large populations. Despite coding irregularities and limited clinical details, administrative data supplemented by tools such as the Agency for Healthcare Research and Quality (AHRQ) patient safety indicators (PSIs) could serve as a screen for potential patient safety problems that merit further investigation, offer valuable insights into adverse impacts and risks of medical errors and, to some extent, provide benchmarks for tracking progress in patient safety efforts at local, state, or national levels.
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Affiliation(s)
- C Zhan
- Center for Quality Improvement and Patient Safety, Agency for Healthcare Research and Quality, Department of Health and Human Services, Rockville, MD 20852, USA.
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Abstract
BACKGROUND Recent evidence suggests that the frequency response requirements for peak expiratory flow (PEF) meters are higher than was first thought and that the American Thoracic Society (ATS) waveforms to test PEF meters may not be adequate for the purpose. METHODS The dynamic response of mini-Wright (MW), Vitalograph (V), TruZone (TZ), MultiSpiro (MS) and pneumotachograph (PT) flow meters was tested by delivering two differently shaped flow-time profiles from a computer controlled explosive decompression device fitted with a fast response solenoid valve. These profiles matched population 5th and 95th centiles for rise time from 10% to 90% of PEF and dwell time of flow above 90% PEF. Profiles were delivered five times with identical chamber pressure and solenoid aperture at PEF. Any difference in recorded PEF for the two profiles indicates a poor dynamic response. RESULTS The absolute (% of mean) flow differences in l/min for the V, MW, and PT PEF meters were 25 (4.7), 20 (3.9), and 2 (0.3), respectively, at PEF approximately 500 l/min, and 25 (10.5), 20 (8.7) and 6 (3.0) at approximately 200 l/min. For TZ and MS meters at approximately 500 l/min the differences were 228 (36.1) and 257 (39.2), respectively, and at approximately 200 l/min they were 51 (23.9) and 1 (0.5). All the meters met ATS accuracy requirements when tested with their waveforms. CONCLUSIONS An improved method for testing the dynamic response of flow meters detects marked overshoot (underdamping) of TZ and MS responses not identified by the 26 ATS waveforms. This error could cause patient misclassification when using such meters with asthma guidelines.
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Affiliation(s)
- M R Miller
- Department of Medicine, University of Birmingham, Selly Oak Hospital, Birmingham, UK.
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Miller MR, Sigsgaard T, Omland O, Pedersen OF. Time domain and flow indices of bronchial hyperresponsiveness: association with asthma symptoms, atopy and smoking. Eur Respir J 2002; 20:86-91. [PMID: 12166587 DOI: 10.1183/09031936.02.00208602] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [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: 11/05/2022]
Abstract
Conventional measures of bronchial hyperresponsiveness (BHR) are only weakly associated with respiratory symptoms in epidemiological studies. Partial and maximal forced expiratory manoeuvres were recorded during histamine challenge testing in 1,959 young male farmers. Analysis was performed to test whether novel measures of BHR, using alternative flow and time domain indices, are more closely associated with asthma symptoms, smoking status and atopy than forced expiratory volume in one second (FEV1) and conventional measures of BHR. The first moments to 75% and 90% of the forced vital capacity (FVC) were calculated from full (F) and partial (P) forced expiratory manoeuvres (i.e. alpha1 75%F, alpha1 75%P), together with the instantaneous flows when 40% and 30% of the FVC remained to be expired (MEF40 and MEF30). BHR was measured by the provocative dose causing a 20% change (PD20) in the FEV1 and alpha1 75%, and also by the method of log dose slopes (LDS). Asthma was diagnosed from symptoms associated with asthma in 158 (8.1%) of the subjects. PD20 FEV1 could only be recorded in 190 subjects (9.7%), of whom only 48 had asthma, whereas LDSFEV1 was recorded in 1,725 (88%) subjects. From the prechallenge data, alpha1 75%, expressed as standardised residuals, showed the largest difference between smokers with and without asthma symptoms, and no indices showed significant differences between nonsmokers with and without asthma symptoms. From BHR data in both smokers and nonsmokers, LDSFEV1 showed one of the largest differences between those with and without asthma symptoms. With smoking status and atopy accounted for, the greatest partial correlation with asthma diagnosis was found for LDSMEF40P, and then for LDSFEV1, but LDSMEF40P was measurable in only just over one-half of the subjects. The authors conclude that time-domain indices are promising measures for longitudinal epidemiological studies concerning the relationship between bronchial hyperresonsiveness and environmental exposures. However, indices from the partial flow-volume loop suffer from censored data.
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Affiliation(s)
- M R Miller
- Dept of Medicine, University of Birmingham, UK.
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Mokotoff M, Mocarski YM, Gentsch BL, Miller MR, Zhou JH, Chen J, Ball ED. Caution in the use of 2-iminothiolane (Traut's reagent) as a cross-linking agent for peptides. The formation of N
-peptidyl-2-iminothiolanes with bombesin (BN) antagonist (d
-Trp6
,Leu13
-ψ[CH2
NH]-Phe14
)BN6−14
and d
-Trp-Gln-Trp-NH2. ACTA ACUST UNITED AC 2002; 57:383-9. [PMID: 11350598 DOI: 10.1034/j.1399-3011.2001.00845.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [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: 11/23/2022]
Abstract
During a study aimed at generating a bispecific molecule between BN antagonist (D-Trp(6),Leu(13)-psi[CH(2)NH]-Phe(14))BN(6-14) (Antag1) and mAb22 (anti-FcgammaRI), we attempted to cross-link the two molecules by introducing a thiol group into Antag1 via 2-iminothiolane (2-IT, Traut's reagent). We found that reaction of Antag1 with 2-IT, when observed using HPLC, affords two products, but that the later eluting peptide is rapidly transformed into the earlier eluting peptide. To understand what was occurring we synthesized a model peptide, D-Trp-Gln-Trp-NH(2) (TP1), the N-terminal tripeptide of Antag1. Reaction of TP1 with 2-IT for 5 min gave products 1a and 3a; the concentration of 1a decreased with reaction time, whereas that of 3a increased. Thiol 1a, the expected Traut product, was identified by collecting it in a vial containing N-methylmaleimide and then isolating the resultant Michael addition product 2a, which was confirmed by mass spectrometry. Thiol 1a is stable at acidic pH, but is unstable at pH 7.8, cyclizes and loses NH3 to give N-TP1-2-iminothiolane (3a), ES-MS (m/z) [602.1 (M+H)(+)], as well as regenerating TP1. Repeat reaction with Antag1 and 2-IT allowed us to isolate N-Antag1-2-iminothiolane (3b), FAB-MS (m/z) [1212.8 (M+H)(+)] and trap the normal Traut product 1b as its N-methylmaleimide Michael addition product 2b, ES-MS (m/z) [1340.8 (M+H)(+)]. Thiol 1b is also stable at acidic pH, but when neutralized is unstable and cyclizes, forming 3b and Antag1.
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Affiliation(s)
- M Mokotoff
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, PA 15261, USA.
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Wilson CM, Bakewell SE, Miller MR, Hart ND, McMorrow RCN, Barry PW, Collier DJ, Watt SJ, Pollard AJ. Increased resting bronchial tone in normal subjects acclimatised to altitude. Thorax 2002; 57:400-4. [PMID: 11978915 PMCID: PMC1746327 DOI: 10.1136/thorax.57.5.400] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [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: 11/03/2022]
Abstract
BACKGROUND Normal subjects frequently experience troublesome respiratory symptoms when acclimatised to altitude. Bronchial hyperresponsiveness (BHR) and full and partial flow-volume loops were measured before and after ascent to 5000 m altitude to determine if there are changes in resting bronchial tone and BHR that might explain the symptoms. METHODS BHR to histamine was measured using a turbine spirometer to record partial and full flow-volume curves and expressed as log dose slopes. Twenty one subjects were tested at sea level and after acclimatisation at 5000 m altitude. RESULTS No significant change in log dose slope measurements of forced expiratory volume in 1 second occurred after acclimatisation, and the maximal expiratory flow with 30% of forced vital capacity remaining (MEF(30%)) rose on the full loop and fell on the partial loop. Their ratio (full divided by partial) rose on average by 0.28 (95% confidence limits 0.14 to 0.42) from the mean (SD) sea level value of 0.87 (0.20). CONCLUSIONS There is no increase in BHR in normal subjects acclimatised to altitude but an increase in resting bronchial tone occurs that could be released by deep inspiration. This may be the result of increased cholinergic tone.
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Affiliation(s)
- C M Wilson
- Department of Anaesthesia, Sheffield Children's Hospital, Sheffield, UK
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Abstract
The frequency content of the first second of the maximum forced expiratory manoeuvre (MFEM) was measured to determine if the currently accepted frequency limit of 20 Hz for MFEM is adequate for recording peak expiratory flow (PEF). The frequency response of a Fleisch pneumotachograph (PT) was measured and used to record MFEM from 24 patients attending a lung-function laboratory and 26 normal volunteers. The first 1.024 s of the signal recorded at 1,000 Hz for that blow with maximum PEF, underwent fast Fourier transformation using a triangular window function, applied after 0.75 s to reduce flow linearly to zero. All the frequencies above a set limit were removed, followed by inverse transformation to reconstitute the blow. The limits for this frequency cut-off were progressively varied from 100 Hz down to 15 Hz, with the resulting PEF being compared with the PEF from the reconstituted blow with no frequency reduction. The average+/-SD age for the group was 47+/-18 yrs and the average PEF was 450+/-187 L x min(-1), which, when expressed as a standardized residual, was 0.1+/-2.1, with a range from -4.5-3.9 indicating a good spread around normal values. Average rise time to PEF was 83+/-38 ms and dwell time >90% PEF was 45+/-25 ms. Cut-off >20 Hz reduced the mean PEF of the group by 8.5 L x min(-1) (95% confidence limit 5.5-11.4 L x min(-1)), whereas cut-off >30 Hz reduced mean PEF by 4.4 L x min(-1) (2.6-6.2). In the present study subjects, 30 Hz was on the 95th percentile of frequencies for defining the upper limit for 98% of the power spectrum for the first second of the blow. It has been shown that there are frequencies >20 Hz that contribute to peak expiratory flow enough to influence readings made using conventional hand-held peak expiratory flow meters, such as the mini-Wright. Devices used for recording flow from a maximum forced expiratory manoeuvre should therefore have an adequate frequency response of up to 30 Hz.
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Affiliation(s)
- M R Miller
- Dept of Medicine, University of Birmingham, Selly Oak Hospital, UK.
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Abstract
The spirometric devices currently available are not well suited for continuous or ambulatory monitoring of subjects. The proposed solution details a method of assessing lung function that avoids the need for flow measurement at the mouth and provides more detailed information of the dynamics of chest motion while allowing the subject to move freely. The solution to this problem comprises a distributed sensor system that allows regional motions during breathing manoeuvres to be investigated as well as a measurement of tidal respiratory volume. Preliminary studies demonstrate performance benefits of an array of sensors over two-compartment respiratory measurements.
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Affiliation(s)
- T Earthrowl-Gould
- Department of Mechanical and Electrical Engineering, School of Engineering and Applied Science, Aston University, Birmingham, UK
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Zhan C, Sangl J, Bierman AS, Miller MR, Friedman B, Wickizer SW, Meyer GS. Potentially inappropriate medication use in the community-dwelling elderly: findings from the 1996 Medical Expenditure Panel Survey. JAMA 2001; 286:2823-9. [PMID: 11735757 DOI: 10.1001/jama.286.22.2823] [Citation(s) in RCA: 372] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
CONTEXT Inappropriate medication use is a major patient safety concern, especially for the elderly population. Using explicit criteria, prior studies have found that 23.5% and 17.5% of the US community-dwelling elderly population used at least 1 of 20 potentially inappropriate medications in 1987 and 1992, respectively. OBJECTIVES To determine the prevalence of potentially inappropriate medication use in community-dwelling elderly persons in 1996, to assess trends over 10 years, categorize inappropriate medication use according to explicit criteria, and to examine risk factors for inappropriate medication use. DESIGN, SETTING, AND PARTICIPANTS Respondents aged 65 years or older (n = 2455) to the 1996 Medical Expenditure Panel Survey, a nationally representative survey of the US noninstitutionalized population were included. A 7-member expert panel was convened to categorize inappropriate medications. MAIN OUTCOME MEASURE Prevalence of use of 33 potentially inappropriate medications. RESULTS In 1996, 21.3% (95% confidence interval [CI], 19.5%-23.1%) of community-dwelling elderly patients in the United States received at least 1 of 33 potentially inappropriate medications. Using the expert panel's classifications, about 2.6% of elderly patients (95% CI, 2.0%-3.2%) used at least 1 of the 11 medications that should always be avoided by elderly patients; 9.1% (95% CI, 7.9%-10.3%) used at least 1 of the 8 that would rarely be appropriate; and 13.3% (95% CI, 11.7%-14.9%) used at least 1 of the 14 medications that have some indications but are often misused. Use of some inappropriate medications declined between 1987 and 1996. Persons with poor health and more prescriptions had a significantly higher risk of inappropriate medication use. CONCLUSIONS Overall inappropriate medication use in elderly patients remains a serious problem. Despite challenges in using explicit criteria for assessing inappropriate medications for elderly patients, such criteria can be applied to population-based surveys to identify opportunities to improve quality of care and patient safety. Enhancements of existing data sources to include dosage, duration, and indication may augment national improvement and monitoring efforts.
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Affiliation(s)
- C Zhan
- Center for Quality Improvement and Patient Safety, Agency for Healthcare Research and Quality, 6011 Executive Blvd, Suite 200, Rockville, MD 20852, USA.
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Miller MR, Elixhauser A, Zhan C, Meyer GS. Patient Safety Indicators: using administrative data to identify potential patient safety concerns. Health Serv Res 2001; 36:110-32. [PMID: 16148964 PMCID: PMC1383610] [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: 05/04/2023] Open
Abstract
OBJECTIVE To develop Patient Safety Indicators (PSI) to identify potential in-hospital patient safety problems for the purpose of quality improvement. DATA SOURCE/STUDY DESIGN The data source was 2,400,000 discharge records in the 1997 New York State Inpatient Database. PSI algorithms were developed using systematic literature reviews of indicators and hand searches of the ICD-9-CM code book. The prevalence of PSI events and associations between PSI events and patient-level and hospital-level characteristics, length of stay, in-hospital mortality, and hospital charges were examined. PRINCIPAL FINDINGS PSIs were developed for 12 distinct clinical situations and an overall summary measure. The 1997 event rates per 10,000 discharges varied from 1.1 for foreign bodies left during procedure to 84.7 for birth traumas. Discharge records with PSI events had twofold to threefold longer hospital stays, twofold to 20-fold higher rates of in-hospital mortality, and twofold to eightfold higher total charges than records without PSI events. Multivariate logistic regression revealed that PSI events were primarily associated with increasing age (p < .001), hospitals performing more inpatient surgery (p < .001), and hospitals with higher percentage of beds in intensive care units (p < .001). CONCLUSIONS The PSIs provide an efficient and user-friendly tool to identify potential inhospital patient safety problems for targeted institution-level quality improvement efforts. Until better error-reporting systems are developed the PSIs can serve to shed light on the problem of medical errors not limited solely to mortality because of errors.
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Affiliation(s)
- M R Miller
- Center for Quality Improvement and Patient Safety, Agency for Healthcare Research and Quality, Rockville, MD 20852, USA
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Abstract
As consumers, payers, and regulatory agencies require evidence regarding quality of care, the demand for intensive care unit (ICU) quality measures will likely grow. ICU providers and professional societies may need to partner with experts in quality measurement to develop and implement quality measures. This essay outlines the steps for developing and implementing quality measures and provides examples of potential ICU quality indicators. Outcome measures, in particular mortality rates, require risk adjustment, making data collection burdensome and broad implementation unlikely. On the other hand, structure and process measures may be feasible to implement broadly. Given the steps for developing quality measures outlined in this essay and the growing evidence in the literature regarding the impact of ICU care, the future should realize the development and implementation of ICU quality indicators that are rigorously developed and provide insights into opportunities to improve the quality of ICU care.
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Affiliation(s)
- P J Pronovost
- Department of Anesthesiology/CCM, The Johns Hopkins Medical Institutions, 600 N. Wolfe Street, Baltimore, MD 21287, USA.
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Abstract
A diagnostic probe was used to estimate the activity of Fenton-derived hydroxyl radicals (.OH), reaction kinetics, and oxidation efficiency in batch suspensions comprised of silica sand, crushed goethite (alpha-FeOOH) ore, peat, and H2O2 (0.13 mM). A simple method of kinetic analysis is presented and used to estimate the rate of .OH production (POH) and scavenging term (ks), which were used to establish the influence of organic matter (Pahokee peat) in Fenton systems. POH was greater in the peat-amended systems than in the unamended control, and ks was approximately the same. Any increase in scavenging of .OH that resulted from the addition of peat was insignificant in comparison to radical scavenging by reaction with H2O2. Also, treatment efficiency, defined as the ratio of probe conversion to H2O2 consumption over the same period was greater in the peat-amended system. Results suggest that .OH production is enhanced in the presence of peat by one or more peat-dependent mechanisms. Fe concentration and availability in the peat, reduction of Fe(III) to Fe(II) by the organic matter, and reduction of organic-complexed Fe(III) to Fe(II) are discussed in the context of the Fenton mechanism.
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Affiliation(s)
- S G Huling
- United States Environmental Protection Agency, Robert S. Kerr Environmental Research Center, P.O. Box 1198, Ada, OK 74820, USA.
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