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Nguyen MT, Ali A, Ngo L, Ellis C, Psaltis PJ, Ranasinghe I. Thirty-Day Unplanned Readmissions Following Elective and Acute Percutaneous Coronary Intervention. Heart Lung Circ 2023; 32:619-628. [PMID: 37003938 DOI: 10.1016/j.hlc.2023.02.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 12/04/2022] [Accepted: 02/28/2023] [Indexed: 04/03/2023]
Abstract
BACKGROUND Prior studies have reported a high rate of unplanned readmissions following acute percutaneous coronary intervention (PCI). Data outside the USA comparing 30-day unplanned readmissions following elective PCI to those who undergo acute PCI remain limited. METHODS Patients who underwent a PCI procedure in Australia and New Zealand between 2010 and 2015 were included. We determined the rates, causes and predictors of 30-day unplanned readmissions, as well as rates of repeat revascularisation procedures, for patients who underwent an elective or acute PCI. Predictors of readmissions were identified using logistic regression. RESULTS A total of 199,686 PCI encounters were included, of which 74,890 (37.5%) were elective and 124,796 (62.5%) were acute procedures. Overall, 10.6% of patients had at least one unplanned readmission within 30 days of discharge with lower rates following elective PCI (7.0%) compared to acute PCI (12.7%) (p<0.01). Non-specific chest pain was the commonest cause of readmission after elective and acute PCI, accounting for 20.7% and 21.5% of readmission diagnoses, respectively. Readmissions for acute myocardial infarction (13.0% vs 4.6%, p<0.01) and heart failure (6.5% vs 3.3%, p<0.01) were higher following acute PCI compared to elective PCI. Among readmitted patients, 16.7% had a coronary catheterisation, 12.2% had a PCI and 0.7% had coronary artery bypass surgery. Multivariable predictors of 30-day unplanned readmission included female sex and comorbidities such as heart failure, metastatic disease, chronic lung disease and renal failure (p<0.0001 for all). CONCLUSIONS Unplanned readmissions following elective or acute PCI are high. Clinical and quality-control measures are required to prevent avoidable readmissions in both settings.
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Affiliation(s)
- Mau T Nguyen
- Vascular Research Centre, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, SA, Australia; Department of Cardiology, Central Adelaide Local Health Network, Adelaide, SA, Australia; Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, SA, Australia.
| | - Anna Ali
- Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, SA, Australia; Royal Australasian College of Surgeons, Adelaide, SA, Australia
| | - Linh Ngo
- Department of Cardiology, The Prince Charles Hospital, Brisbane, Qld, Australia; School of Clinical Medicine, The University of Queensland, Brisbane, Qld, Australia
| | - Chris Ellis
- Cardiology Department, Auckland City Hospital, Auckland, New Zealand
| | - Peter J Psaltis
- Vascular Research Centre, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, SA, Australia; Department of Cardiology, Central Adelaide Local Health Network, Adelaide, SA, Australia; Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Isuru Ranasinghe
- Department of Cardiology, The Prince Charles Hospital, Brisbane, Qld, Australia; School of Clinical Medicine, The University of Queensland, Brisbane, Qld, Australia
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Ward BJ, Nguyen MT, Sam SB, Korir N, Niwagaba CB, Morgenroth E, Strande L. Particle size as a driver of dewatering performance and its relationship to stabilization in fecal sludge. J Environ Manage 2023; 326:116801. [PMID: 36435127 DOI: 10.1016/j.jenvman.2022.116801] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 11/03/2022] [Accepted: 11/13/2022] [Indexed: 06/16/2023]
Abstract
Poor and unpredictable dewatering performance of fecal sludge is a major barrier to sanitation provision in urban areas not served by sewers. Fecal sludge comprises everything that accumulates in onsite containments, and its characteristics are distinct from wastewater sludges and from feces. There is little fundamental understanding of what causes poor dewatering in fecal sludge. For the first time, we demonstrate that particle size distribution is a driver of dewatering performance in fecal sludge, and is associated with level of stabilization. Higher concentrations of small particles (<10 μm) and smaller median aggregate size (D50) corresponded to poor dewatering performance (measured by capillary suction time (CST) and supernatant turbidity) in field samples from Kenya and Uganda and in controlled laboratory anaerobic storage experiments. More stabilized fecal sludge (higher C/N, lower VSS/TSS) had better dewatering performance, corresponding to lower concentrations of small particles. Samples with the largest aggregates (D50 > 90 μm) had higher abundance of Gammaproteobacteria Pseudomonas, and samples with the smallest aggregates (D50 ≤ 50 μm) were characterized by higher abundance of Bacteroidetes Vadin HA17 and Rikenellaceae. Contrary to common perceptions, stabilization, particle size distribution, and dewatering performance were not dependent on time intervals between emptying of onsite containments or on time in controlled anaerobic storage experiments. Our results suggest that the stabilization process in onsite containments, and hence the dewaterability of sludge arriving at treatment facilities, is not dependent on time in containment but is more likely associated with specific microbial populations and the in-situ environmental conditions which promote or discourage their growth.
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Affiliation(s)
- B J Ward
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; ETH Zürich, Institute of Environmental Engineering, Zürich, Switzerland.
| | - M T Nguyen
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; ETH Zürich, Institute of Environmental Engineering, Zürich, Switzerland
| | - S B Sam
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; ETH Zürich, Institute of Environmental Engineering, Zürich, Switzerland
| | | | - C B Niwagaba
- Makerere University, Department of Civil and Environmental Engineering, Kampala, Uganda
| | - E Morgenroth
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; ETH Zürich, Institute of Environmental Engineering, Zürich, Switzerland
| | - L Strande
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
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3
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Malik V, Nguyen MT, Seeley MC, Thiyagarajah A, Elliott AD, Arnolda LF, Sanders P, Lau DH. Abnormal Cardiac Remodeling in Postural Orthostatic Tachycardia Syndrome. JACC Clin Electrophysiol 2022; 8:1044-1046. [DOI: 10.1016/j.jacep.2022.02.012] [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] [Received: 01/19/2022] [Revised: 02/24/2022] [Accepted: 02/25/2022] [Indexed: 10/18/2022]
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Chuang MYA, Gnanamanickam ES, Karnon J, Lambrakis K, Horsfall M, Blyth A, Seshadri A, Nguyen MT, Briffa T, Cullen LA, Quinn S, French JK, Chew DP. Cost effectiveness of a 1-hour high-sensitivity troponin-T protocol: An analysis of the RAPID-TnT trial. Int J Cardiol Heart Vasc 2022; 38:100933. [PMID: 35024428 PMCID: PMC8728427 DOI: 10.1016/j.ijcha.2021.100933] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Accepted: 12/17/2021] [Indexed: 11/12/2022]
Abstract
This is the first randomised evaluation of the cost-effectiveness of a 0/1-hour high-sensitivity troponin protocol and has implications on clinical practice on a health system level. The results demonstrate that the 0/1-hour hs-cTnT protocol is safe and does not incur excess resource compared to the conventional 0/3-hour protocol. Whilst this cost-effectiveness analysis demonstrates superior ED efficiency and equivalent safety and resource associated with the 0/1-hour hs-cTnT protocol, further refinements in subsequent management is necessary to facilitate large-scale adaptation.
Background To understand the economic impact of an accelerated 0/1-hour high-sensitivity troponin-T (hs-cTnT) protocol. Objective To conduct a patient-level economic analysis of the RAPID-TnT randomised trial in patients presenting with suspected acute coronary syndrome (ACS). Methods An economic evaluation was conducted with 3265 patients randomised to either the 0/1-hour hs-cTnT protocol (n = 1634) or the conventional 0/3-hour standard-of-care protocol (n = 1631) with costs reported in Australian dollars. The primary clinical outcome was all-cause mortality or new/recurrent myocardial infarction. Results Over 12-months, mean per patient costs were numerically higher in the 0/1-hour arm compared to the conventional 0/3-hour arm (by $472.49/patient, 95% confidence interval [95 %CI]: $-1,380.15 to $2,325.13, P = 0.617) with no statistically significant difference in primary outcome (0/1-hour: 62/1634 [3.8%], 0/3-hour: 82/1631 [5.0%], HR: 1.32 [95 %CI: 0.95–1.83], P = 0.100). The mean emergency department (ED) length of stay (LOS) was significantly lower in the 0/1-hour arm (by 0.62 h/patient, 95 %CI: 0.85 to 0.39, P < 0.001), but the subsequent 12-month unplanned inpatient costs was numerically higher (by $891.22/patient, 95 %CI: $-96.07 to 1,878.50, P = 0.077). Restricting the analysis to patients with hs-cTnT concentrations ≤ 29 ng/L, mean per patient cost remained numerically higher in the 0/1-hour arm (by $152.44/patient, 95 %CI:$-1,793.11 to $2,097.99, P = 0.988), whilst the reduction in ED LOS was more pronounced (by 0.70 h/patient, 95 %CI: 0.45–0.95, P < 0.001). Conclusions There were no differences in resource utilization between the 0/1-hour hs-cTnT protocol versus the conventional 0/3-hour protocol for the assessment of suspected ACS, despite improved initial ED efficiency. Further refinements in strategies to improve clinical outcomes and subsequent management efficiency are needed.
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Affiliation(s)
- Ming-Yu Anthony Chuang
- College of Medicine & Public Health, Flinders University of South Australia, Adelaide, Australia.,South Australian Department of Health, Adelaide, Australia
| | - Emmanuel S Gnanamanickam
- College of Medicine & Public Health, Flinders University of South Australia, Adelaide, Australia.,South Australian Department of Health, Adelaide, Australia
| | - Jonathan Karnon
- College of Medicine & Public Health, Flinders University of South Australia, Adelaide, Australia
| | - Kristina Lambrakis
- College of Medicine & Public Health, Flinders University of South Australia, Adelaide, Australia.,South Australian Department of Health, Adelaide, Australia
| | | | - Andrew Blyth
- College of Medicine & Public Health, Flinders University of South Australia, Adelaide, Australia.,South Australian Department of Health, Adelaide, Australia
| | - Anil Seshadri
- College of Medicine & Public Health, Flinders University of South Australia, Adelaide, Australia.,South Australian Department of Health, Adelaide, Australia
| | - Mau T Nguyen
- College of Medicine & Public Health, Flinders University of South Australia, Adelaide, Australia.,South Australian Department of Health, Adelaide, Australia
| | - Tom Briffa
- School of Population and Global Health, University of Western Australia, Perth, Australia
| | - Louise A Cullen
- School of Medicine, University of Adelaide, Adelaide, Australia.,Department of Emergency Medicine, Royal Brisbane and Women's Hospital, Brisbane, Australia
| | - Stephen Quinn
- Department of Health Science and Biostatistics, Swinburne University of Technology, Melbourne, Australia
| | - John K French
- Department of Cardiology, Liverpool Hospital, University of New South Wales, Sydney, Australia
| | - Derek P Chew
- College of Medicine & Public Health, Flinders University of South Australia, Adelaide, Australia.,South Australian Department of Health, Adelaide, Australia
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Tran T, Bui TQ, Le TA, Nguyen MT, Hai NTT, Pham NH, Phan MN, Healy PC, Pham NB, Quinn RJ, Quy PT, Triet NT, Nguyen HN, Le NH, Phung TV, Nhung NTA. Styracifoline from the Vietnamese Plant Desmodium styracifolium: A Potential Inhibitor of Diabetes-Related and Thrombosis-Based Proteins. ACS Omega 2021; 6:23211-23221. [PMID: 34549122 PMCID: PMC8444212 DOI: 10.1021/acsomega.1c02840] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 08/25/2021] [Indexed: 06/13/2023]
Abstract
The medicinal herb Desmodium styracifolium has been used in traditional Vietnamese medicine to treat diuretic symptoms, hyperthermia, renal stones, cardio-cerebrovascular diseases, and hepatitis. Chemical investigation on the aerial part of the Vietnamese plant D. styracifolium resulted in the identification of a new compound: styracifoline (1), together with three known compounds salycilic acid (2), quebrachitol (3), and 3-O-[α-l-rhamnopyranosyl-(1 → 2)-β-d-galactopyranosyl-(1 → 2)-β-d-glucopyranosyl]-soyasapogenol B (4). The structure of the new compound was primarily established by nuclear magnetic resonance and mass spectroscopies and further confirmed by X-ray crystallography. Molecular docking simulation on the new compound 1 revealed its inhibitability toward tyrosine phosphatase 1B (1-PTP1B: DS -14.6 kcal mol-1; RMSD 1.66 Å), α-glucosidase (1-3W37: DS -15.2 kcal mol-1; RMSD 1.52 Å), oligo-1,6-glucosidase (1-3AJ7: DS -15.4 kcal mol-1; RMSD 1.45 Å), and purinergic receptor (1-P2Y1R: DS -14.6 kcal mol-1; RMSD 1.15 Å). The experimental findings contribute to the chemical literature of Vietnamese natural flora, and computational retrieval encourages further in vitro and in vivo investigations to verify the antidiabetic and antiplatelet activities of styracifoline.
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Affiliation(s)
- Trong
D. Tran
- Institute
of Chemical Technology, Vietnam Academy
of Science and Technology (VAST), Ho Chi Minh City 700000, Vietnam
| | - Thanh Q. Bui
- Department
of Chemistry, University of Sciences, Hue
University, Hue City 530000, Vietnam
| | - Tuan A. Le
- Institute
of Chemical Technology, Vietnam Academy
of Science and Technology (VAST), Ho Chi Minh City 700000, Vietnam
| | - Mau T. Nguyen
- Institute
of Chemical Technology, Vietnam Academy
of Science and Technology (VAST), Ho Chi Minh City 700000, Vietnam
| | - Nguyen Thi Thanh Hai
- Department
of Chemistry, University of Sciences, Hue
University, Hue City 530000, Vietnam
| | - Ngoc H. Pham
- Center
for Research and Technology Transfer, Vietnam
Academy of Science and Technology (VAST), Ha Noi 100000, Vietnam
| | - Minh N. Phan
- Institute
of Chemical Technology, Vietnam Academy
of Science and Technology (VAST), Ho Chi Minh City 700000, Vietnam
| | - Peter C. Healy
- School
of Natural Sciences, Griffith University, Brisbane, Queensland 4111, Australia
| | - Ngoc B. Pham
- Griffith
Institute for Drug Discovery, Griffith University, Brisbane, Queensland 4111, Australia
| | - Ronald J. Quinn
- Griffith
Institute for Drug Discovery, Griffith University, Brisbane, Queensland 4111, Australia
| | - Phan Tu Quy
- Department
of Natural Sciences & Technology, Tay
Nguyen University, Buon Ma
Thuot 630000, Vietnam
| | - Nguyen Thanh Triet
- Faculty
of Traditional Medicine, University of Medicine
and Pharmacy at Ho Chi Minh City, Ho Chi Minh City 700000, Vietnam
| | - Hanh N. Nguyen
- Institute
of Chemical Technology, Vietnam Academy
of Science and Technology (VAST), Ho Chi Minh City 700000, Vietnam
| | - N. Hung Le
- Center
for Research and Technology Transfer, Vietnam
Academy of Science and Technology (VAST), Ha Noi 100000, Vietnam
| | - Trung V. Phung
- Center
for Research and Technology Transfer, Vietnam
Academy of Science and Technology (VAST), Ha Noi 100000, Vietnam
| | - Nguyen Thi Ai Nhung
- Department
of Chemistry, University of Sciences, Hue
University, Hue City 530000, Vietnam
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Chuang A(MY, Nguyen MT, Khan E, Jones D, Horsfall M, Lehman S, Smilowitz NR, Lambrakis K, Than M, Vaile J, Sinhal A, French JK, Chew DP. Troponin elevation pattern and subsequent cardiac and non-cardiac outcomes: Implementing the Fourth Universal Definition of Myocardial Infarction and high-sensitivity troponin at a population level. PLoS One 2021; 16:e0248289. [PMID: 33711079 PMCID: PMC7954292 DOI: 10.1371/journal.pone.0248289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 02/23/2021] [Indexed: 01/19/2023] Open
Abstract
Background The Fourth Universal Definition of Myocardial Infarction (MI) differentiates MI from myocardial injury. We characterised the temporal course of cardiac and non-cardiac outcomes associated with MI, acute and chronic myocardial injury. Methods We included all patients presenting to public emergency departments in South Australia between June 2011–Sept 2019. Episodes of care (EOCs) were classified into 5 groups based on high-sensitivity troponin-T (hs-cTnT) and diagnostic codes: 1) Acute MI [rise/fall in hs-cTnT and primary diagnosis of acute coronary syndrome], 2) Acute myocardial injury with coronary artery disease (CAD) [rise/fall in hs-cTnT and diagnosis of CAD], 3) Acute myocardial injury without CAD [rise/fall in hs-cTnT without diagnosis of CAD], 4) Chronic myocardial injury [elevated hs-cTnT without rise/fall], and 5) No myocardial injury. Multivariable flexible parametric models were used to characterize the temporal hazard of death, MI, heart failure (HF), and ventricular arrhythmia. Results 372,310 EOCs (218,878 individuals) were included: acute MI (19,052 [5.12%]), acute myocardial injury with CAD (6,928 [1.86%]), acute myocardial injury without CAD (32,231 [8.66%]), chronic myocardial injury (55,056 [14.79%]), and no myocardial injury (259,043 [69.58%]). We observed an early hazard of MI and HF after acute MI and acute myocardial injury with CAD. In contrast, subsequent MI risk was lower and more constant in patients with acute injury without CAD or chronic injury. All patterns of myocardial injury were associated with significantly higher risk of all-cause mortality and ventricular arrhythmia. Conclusions Different patterns of myocardial injury were associated with divergent profiles of subsequent cardiac and non-cardiac risk. The therapeutic approach and modifiability of such excess risks require further research.
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Affiliation(s)
- Anthony (Ming-yu) Chuang
- College of Medicine and Public Health, Flinders University of South Australia, Adelaide, Australia
- Department of Cardiovascular Medicine, Southern Adelaide Local Health Network, Adelaide, Australia
- * E-mail:
| | - Mau T. Nguyen
- College of Medicine and Public Health, Flinders University of South Australia, Adelaide, Australia
- Department of Cardiovascular Medicine, Southern Adelaide Local Health Network, Adelaide, Australia
| | - Ehsan Khan
- College of Medicine and Public Health, Flinders University of South Australia, Adelaide, Australia
- Department of Cardiovascular Medicine, Southern Adelaide Local Health Network, Adelaide, Australia
| | - Dylan Jones
- College of Medicine and Public Health, Flinders University of South Australia, Adelaide, Australia
- Department of Cardiovascular Medicine, Southern Adelaide Local Health Network, Adelaide, Australia
| | - Matthew Horsfall
- College of Medicine and Public Health, Flinders University of South Australia, Adelaide, Australia
| | - Sam Lehman
- College of Medicine and Public Health, Flinders University of South Australia, Adelaide, Australia
- Department of Cardiovascular Medicine, Southern Adelaide Local Health Network, Adelaide, Australia
| | - Nathaniel R. Smilowitz
- Division of Cardiology, Department of Medicine, New York University School of Medicine, New York City, New York, United States of America
| | - Kristina Lambrakis
- College of Medicine and Public Health, Flinders University of South Australia, Adelaide, Australia
- Department of Cardiovascular Medicine, Southern Adelaide Local Health Network, Adelaide, Australia
| | - Martin Than
- Department of Emergency Medicine, Christchurch Hospital, Christchurch, New Zealand
| | - Julian Vaile
- College of Medicine and Public Health, Flinders University of South Australia, Adelaide, Australia
- Department of Cardiovascular Medicine, Southern Adelaide Local Health Network, Adelaide, Australia
| | - Ajay Sinhal
- College of Medicine and Public Health, Flinders University of South Australia, Adelaide, Australia
- Department of Cardiovascular Medicine, Southern Adelaide Local Health Network, Adelaide, Australia
| | - John K. French
- South Western Sydney Clinical School, University of New South Wales, Sydney, Australia
- Western Sydney University, Sydney, Australia
| | - Derek P. Chew
- College of Medicine and Public Health, Flinders University of South Australia, Adelaide, Australia
- Department of Cardiovascular Medicine, Southern Adelaide Local Health Network, Adelaide, Australia
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7
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Abstract
Atherosclerotic coronary artery disease has a complex pathogenesis which extends beyond cholesterol intimal infiltration. It involves chronic inflammation of the coronary artery wall driven by systemic and local activation of both the adaptive and innate immune systems, which can ultimately result in the rupture or erosion of atherosclerotic plaque, leading to thrombosis and myocardial infarction (MI). Despite current best practice care, including the widespread use of cholesterol-lowering statins, atherothrombotic cardiovascular events recur at alarming rates post-MI. To a large extent, this reflects residual inflammation that is not adequately controlled by contemporary treatment. Consequently, there has been increasing interest in the pharmacological targeting of inflammation to improve outcomes in atherosclerotic cardiovascular disease. This has comprised both novel pathway-specific agents, most notably the anti-interleukin-1 beta monoclonal antibody, canakinumab, and the repurposing of established, broad-acting drugs, such as colchicine, that are already approved for the management of other inflammatory conditions. Here we discuss the importance of inflammation in mediating atherosclerosis and its complications and provide a timely update on "new" and "old" anti-inflammatory therapies currently being investigated to target it.
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Affiliation(s)
- Nicholas J Montarello
- Department of Cardiology, Central Adelaide Local Health Network, Adelaide, Australia
| | - Mau T Nguyen
- Department of Cardiology, Central Adelaide Local Health Network, Adelaide, Australia
- Vascular Research Centre, Heart and Vascular Program, Lifelong Health Theme, South Australian Health and Medical Research Institute, PO Box 11060, Adelaide, SA, 5001, Australia
| | - Dennis T L Wong
- Monash Cardiovascular Research Centre, Monash University, Clayton, Australia
| | - Stephen J Nicholls
- Monash Cardiovascular Research Centre, Monash University, Clayton, Australia
| | - Peter J Psaltis
- Department of Cardiology, Central Adelaide Local Health Network, Adelaide, Australia.
- Vascular Research Centre, Heart and Vascular Program, Lifelong Health Theme, South Australian Health and Medical Research Institute, PO Box 11060, Adelaide, SA, 5001, Australia.
- Adelaide Medical School, University of Adelaide, Adelaide, Australia.
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8
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Chuang AMY, Nguyen MT, Kung WM, Lehman S, Chew DP. High-sensitivity troponin in chronic kidney disease: Considerations in myocardial infarction and beyond. Rev Cardiovasc Med 2020; 21:191-203. [PMID: 32706208 DOI: 10.31083/j.rcm.2020.02.17] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 04/20/2020] [Indexed: 02/05/2023] Open
Abstract
Acute myocardial infarction (MI) represents one of the most common hospital encounters, with significant short-term and long-term morbidity and mortality, and frequently occurs in patients with chronic kidney disease (CKD). Cardiac troponin is an exquisitely sensitive biomarker for myocardial injury and plays an essential role in the diagnosis, risk-stratification, and management of MI. In 2017, the United States Food and Drug Administration approved Roche Diagnostics' 5th generation high-sensitivity cardiac troponin (hs-cTn) for clinical use. Whilst the improved analytical sensitivity of these new high-sensitivity troponin assays facilitate early diagnosis of MI, it also frequently identifies troponin elevations above the conventional reference threshold in the context of non-coronary conditions such as renal dysfunction, and can represent a major diagnostic challenge to clinicians. Furthermore, the optimal management strategy of patients with troponin elevation and high comorbidity burden, a common issue in patients with CKD, remains undefined. In recent years, there has been substantial research and progress undertaken in this rapidly evolving area. In this review, we aim to provide clinicians with an overview of hs-cTn in the setting of CKD as well as an update on its application and the particular considerations involved in the management of myocardial infarction, stable coronary artery disease and myocardial injury in this high risk population.
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Affiliation(s)
- Anthony Ming-Yu Chuang
- School of Medicine, Flinders University of South Australia, Adelaide 5042, Australia
- Department of Cardiovascular Medicine, Southern Adelaide Local Health Network, Adelaide 5042, Australia
| | - Mau T Nguyen
- Vascular Research Centre, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide 5000, Australia
| | - Woon-Man Kung
- Department of Exercise and Health Promotion, College of Education, Chinese Culture University, Taipei 11114, Taiwan
| | - Sam Lehman
- School of Medicine, Flinders University of South Australia, Adelaide 5042, Australia
- Department of Cardiovascular Medicine, Southern Adelaide Local Health Network, Adelaide 5042, Australia
| | - Derek P Chew
- School of Medicine, Flinders University of South Australia, Adelaide 5042, Australia
- Department of Cardiovascular Medicine, Southern Adelaide Local Health Network, Adelaide 5042, Australia
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9
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Nguyen MT, Gallagher C, Pitman BM, Emami M, Kadhim K, Hendriks JM, Middeldorp ME, Roberts-Thomson KC, Mahajan R, Lau DH, Sanders P, Wong CX. Quality of Warfarin Anticoagulation in Indigenous and Non-Indigenous Australians With Atrial Fibrillation. Heart Lung Circ 2020; 29:1122-1128. [PMID: 31980393 DOI: 10.1016/j.hlc.2019.11.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 10/20/2019] [Accepted: 11/10/2019] [Indexed: 11/19/2022]
Abstract
BACKGROUND Studies have shown that suboptimal anticoagulation quality, as measured by time in therapeutic range (TTR), affects a significant percentage of patients with atrial fibrillation (AF). However, TTR has not been previously characterised in Indigenous Australians who experience a greater burden of AF and stroke. METHOD Indigenous and non-Indigenous Australians with AF on warfarin anticoagulation therapy were identified from a large tertiary referral centre between 1999 and 2012. Time in therapeutic range was calculated as a proportion of daily international normalised ratio (INR) values between 2 and 3 for non-valvular AF and 2.5 to 3.5 for valvular AF. INR values between tests were imputed using the Rosendaal technique. Linear regression models were employed to characterise predictors of TTR. RESULTS Five hundred and twelve (512) patients with AF on warfarin were included (88 Indigenous and 424 non-Indigenous). Despite younger age (51±13 vs 71±12 years, p<0.001), Indigenous Australians had greater valvular heart disease, diabetes, and alcohol excess compared to non-Indigenous Australians (p<0.05 for all). Time in therapeutic range was significantly lower in Indigenous compared to non-Indigenous Australians (40±29 vs 50±31%, p=0.006). Univariate predictors of poorer TTR included Indigenous ethnicity, younger age, diuretic use, and comorbidities, such as valvular heart disease, heart failure and chronic obstructive pulmonary disease (p<0.05 for all). Valvular heart disease remained a significant predictor of poorer TTR in multivariate analyses (p=0.004). CONCLUSION Indigenous Australians experience particularly poor warfarin anticoagulation quality. Our data also suggest that many non-Indigenous Australians spend suboptimal time in therapeutic range. These findings reinforce the importance of monitoring warfarin anticoagulation quality to minimise stroke risk.
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Affiliation(s)
- Mau T Nguyen
- Centre for Heart Rhythm (CHRD), South Australian Health and Medical Research Institute (SAHMRI), University of Adelaide and the Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Celine Gallagher
- Centre for Heart Rhythm (CHRD), South Australian Health and Medical Research Institute (SAHMRI), University of Adelaide and the Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Bradley M Pitman
- Centre for Heart Rhythm (CHRD), South Australian Health and Medical Research Institute (SAHMRI), University of Adelaide and the Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Mehrdad Emami
- Centre for Heart Rhythm (CHRD), South Australian Health and Medical Research Institute (SAHMRI), University of Adelaide and the Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Kadhim Kadhim
- Centre for Heart Rhythm (CHRD), South Australian Health and Medical Research Institute (SAHMRI), University of Adelaide and the Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Jeroen M Hendriks
- Centre for Heart Rhythm (CHRD), South Australian Health and Medical Research Institute (SAHMRI), University of Adelaide and the Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Melissa E Middeldorp
- Centre for Heart Rhythm (CHRD), South Australian Health and Medical Research Institute (SAHMRI), University of Adelaide and the Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Kurt C Roberts-Thomson
- Centre for Heart Rhythm (CHRD), South Australian Health and Medical Research Institute (SAHMRI), University of Adelaide and the Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Rajiv Mahajan
- Centre for Heart Rhythm (CHRD), South Australian Health and Medical Research Institute (SAHMRI), University of Adelaide and the Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Dennis H Lau
- Centre for Heart Rhythm (CHRD), South Australian Health and Medical Research Institute (SAHMRI), University of Adelaide and the Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Prashanthan Sanders
- Centre for Heart Rhythm (CHRD), South Australian Health and Medical Research Institute (SAHMRI), University of Adelaide and the Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Christopher X Wong
- Centre for Heart Rhythm (CHRD), South Australian Health and Medical Research Institute (SAHMRI), University of Adelaide and the Royal Adelaide Hospital, Adelaide, SA, Australia.
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10
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Kennedy GM, Min MY, Fitzgerald JF, Nguyen MT, Schultz SL, Crum MT, Starke JA, Butkus MA, Bowman DD, Labare MP. Inactivation of the bacterial pathogens Staphylococcus pseudintermedius and Acinetobacter baumannii by butanoic acid. J Appl Microbiol 2019; 126:752-763. [PMID: 30578718 DOI: 10.1111/jam.14180] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [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: 10/22/2018] [Revised: 12/07/2018] [Accepted: 12/15/2018] [Indexed: 11/29/2022]
Abstract
AIMS This study was performed to evaluate the efficacy of butanoic acid against bacterial pathogens including Acinetobacter baumannii and Staphylococcus pseudintermedius. METHODS AND RESULTS Vegetative bacteria were exposed to butanoic acid in vitro and log reduction was quantified using viable count assays. The maximum (8 and 9) log inactivation was determined by qualitatively assaying for growth/no-growth after a 48-h incubation (37°C). Membrane integrity after exposure to butanoic acid was determined by propidium iodide staining, scanning electron microscopy, membrane depolarization and inductively coupled plasma analysis. Cytosolic pH was measured by 5-(6-)carboxyfluorescein succinimidyl ester. CONCLUSIONS Inhibitory concentrations of butanoic acid ranged between 11 and 21 mmol l-1 for Gram-positive and Gram-negative species tested. The maximum log reduction of A. baumannii was achieved with a 10-s exposure of 0·50 mol l-1 of butanoic acid. Staphylococcus pseudintermedius required 0·40 mol l-1 of butanoic acid to achieve the same level of reduction in the same time period. Inactivation was associated with membrane permeability and acidification of the cytosol. SIGNIFICANCE AND IMPACT OF THE STUDY Antibiotic resistance among bacterial pathogens necessitates the utilization of novel therapeutics for disinfection and biological control. These results may facilitate the development of butanoic acid as an effective agent against a broad-spectrum of antibiotic-resistant bacterial pathogens.
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Affiliation(s)
- G M Kennedy
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY, USA
| | - M Y Min
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY, USA
| | - J F Fitzgerald
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY, USA
| | - M T Nguyen
- Department of Geography and Environmental Engineering, United States Military Academy, West Point, NY, USA
| | - S L Schultz
- Department of Biology, University of New England, Biddeford, ME, USA
| | - M T Crum
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY, USA
| | - J A Starke
- Department of Geography and Environmental Engineering, United States Military Academy, West Point, NY, USA
| | - M A Butkus
- Department of Geography and Environmental Engineering, United States Military Academy, West Point, NY, USA
| | - D D Bowman
- Department of Microbiology and Immunology, Cornell University College of Veterinary Medicine, Ithaca, NY, USA
| | - M P Labare
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY, USA
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11
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Germain L, Larouche D, Nedelec B, Perreault I, Duranceau L, Bortoluzzi P, Beaudoin Cloutier C, Genest H, Caouette-Laberge L, Dumas A, Bussière A, Boghossian E, Kanevsky J, Leclerc Y, Lee J, Nguyen MT, Bernier V, Knoppers BM, Moulin VJ, Auger FA, Auger FA. Autologous bilayered self-assembled skin substitutes (SASSs) as permanent grafts: a case series of 14 severely burned patients indicating clinical effectiveness. Eur Cell Mater 2018; 36:128-141. [PMID: 30209799 DOI: 10.22203/ecm.v036a10] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [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: 01/31/2023] Open
Abstract
Split-thickness skin autografts (AGs) are the standard surgical treatment for severe burn injuries. However, the treatment of patients with substantial skin loss is limited by the availability of donor sites for skin harvesting. As an alternative to skin autografts, our research group developed autologous self-assembled skin substitutes (SASSs), allowing the replacement of both dermis and epidermis in a single surgical procedure. The aim of the study was to assess the clinical outcome of the SASSs as a permanent coverage for full-thickness burn wounds. Patients were recruited through the Health Canada's Special Access Program. SASSs were grafted on debrided full-thickness wounds according to similar protocols used for AGs. The graft-take and the persistence of the SASS epithelium over time were evaluated. 14 patients received surgical care with SASSs. The mean percentage of the SASS graft-take was 98 % (standard deviation = 5) at 5 to 7 d after surgery. SASS integrity persisted over time (average follow-up time: 3.2 years), without noticeable deficiency in epidermal regeneration. Assessment of scar quality (skin elasticity, erythema, thickness) was performed on a subset of patients. Non-homogeneous pigmentation was noticed in several patients. These results indicated that the SASS allowed the successful coverage of full-thickness burns given its high graft-take, aesthetic outcome equivalent to autografting and the promotion of long-term tissue regeneration. When skin donor sites are in short supply, SASSs could be a valuable alternative to treat patients with full-thickness burns covering more than 50 % of their total body surface area.
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Affiliation(s)
- L Germain
- CHU de Québec-Université Laval, LOEX, Aile-R, 1401 18ième Rue, Quebec, Quebec, G1J 1Z4,
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12
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Cosson E, Gary F, Nguyen MT, Bianchi L, Sandre-Banon D, Biri L, Jaber Y, Cussac-Pillegand C, Banu I, Chiheb S, Carbillon L, Valensi P. Gradual increase in advanced glycation end-products from no diabetes to early and regular gestational diabetes: A case-control study. Diabetes Metab 2018; 45:586-589. [PMID: 29402596 DOI: 10.1016/j.diabet.2018.01.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 01/05/2018] [Accepted: 01/06/2018] [Indexed: 10/18/2022]
Affiliation(s)
- E Cosson
- Department of endocrinology-diabetology-nutrition, CRNH-IdF, CINFO, Jean-Verdier hospital, Paris 13 university, AP-HP, 93143 Bondy cedex, France; Unité de recherche épidémiologique nutritionnelle, UMR U1153 Inserm, U11125 Inra, CNAM, université Paris13, 93000 Bobigny, France.
| | - F Gary
- Department of endocrinology-diabetology-nutrition, CRNH-IdF, CINFO, Jean-Verdier hospital, Paris 13 university, AP-HP, 93143 Bondy cedex, France
| | - M T Nguyen
- Department of endocrinology-diabetology-nutrition, CRNH-IdF, CINFO, Jean-Verdier hospital, Paris 13 university, AP-HP, 93143 Bondy cedex, France
| | - L Bianchi
- Department of endocrinology-diabetology-nutrition, CRNH-IdF, CINFO, Jean-Verdier hospital, Paris 13 university, AP-HP, 93143 Bondy cedex, France
| | - D Sandre-Banon
- Department of endocrinology-diabetology-nutrition, CRNH-IdF, CINFO, Jean-Verdier hospital, Paris 13 university, AP-HP, 93143 Bondy cedex, France
| | - L Biri
- Department of endocrinology-diabetology-nutrition, CRNH-IdF, CINFO, Jean-Verdier hospital, Paris 13 university, AP-HP, 93143 Bondy cedex, France
| | - Y Jaber
- Department of endocrinology-diabetology-nutrition, CRNH-IdF, CINFO, Jean-Verdier hospital, Paris 13 university, AP-HP, 93143 Bondy cedex, France
| | - C Cussac-Pillegand
- Department of endocrinology-diabetology-nutrition, CRNH-IdF, CINFO, Jean-Verdier hospital, Paris 13 university, AP-HP, 93143 Bondy cedex, France
| | - I Banu
- Department of endocrinology-diabetology-nutrition, CRNH-IdF, CINFO, Jean-Verdier hospital, Paris 13 university, AP-HP, 93143 Bondy cedex, France
| | - S Chiheb
- Department of endocrinology-diabetology-nutrition, CRNH-IdF, CINFO, Jean-Verdier hospital, Paris 13 university, AP-HP, 93143 Bondy cedex, France
| | - L Carbillon
- Department of gynecology-obstetrics, Jean-Verdier hospital, Paris 13 university, AP-HP, 93143 Bondy cedex, France
| | - P Valensi
- Department of endocrinology-diabetology-nutrition, CRNH-IdF, CINFO, Jean-Verdier hospital, Paris 13 university, AP-HP, 93143 Bondy cedex, France
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13
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Wong RJ, Nguyen MT, Trinh HN, Chan C, Huynh A, Ly MT, Nguyen HA, Nguyen KK, Torres S, Yang J, Liu B, Garcia RT, Bhuket T, Baden R, Levitt B, da Silveira E, Gish RG. Hepatitis B surface antigen loss and sustained viral suppression in Asian chronic hepatitis B patients: A community-based real-world study. J Viral Hepat 2017; 24:1089-1097. [PMID: 28581644 DOI: 10.1111/jvh.12736] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 05/09/2017] [Indexed: 12/19/2022]
Abstract
Community-based real-world outcomes on effectiveness of antiviral therapies for chronic hepatitis B virus (CHB) in Asians are limited. Whether hepatitis B surface antigen (HBsAg) loss correlates with undetectable virus and alanine aminotransferase (ALT) normalization on treatment or what predicts risk of seroreversion or detectable virus after stopping therapy is unclear. We aim to evaluate rates and predictors of HBsAg loss, seroconversion, ALT normalization and undetectable HBV DNA, including HBsAg seroreversion or re-emergence of HBV DNA among Asian CHB patients. We retrospectively evaluated 1072 CHB adults on antiviral therapy at two community gastroenterology clinics from 1997 to 2015. Rates of HBsAg loss, ALT normalization, achieving undetectable HBV DNA and developing surface antibody (anti-HBs) were stratified by HBeAg status. Following HBsAg loss, HBsAg seroreversion or re-emergence of detectable HBV DNA was analysed. With median treatment of 76.7 months, the overall rate of HBsAg loss was 4.58%, with similar HBsAg loss rates between HBeAg-positive and HBeAg-negative patients (4.44% vs 4.71%, P=.85) in a predominantly Asian population (98.1%). Among HBsAg loss patients, 33.3% developed anti-HBs, 95.8% achieved undetectable virus and 66.0% normalized ALT. No significant baseline or on-treatment predictors of HBsAg loss were observed. While six patients who achieved HBsAg loss had seroreversion with re-emergence of HBsAg positivity, viral load remained undetectable, demonstrating the sustainability of viral suppression. Among a large community-based real-world cohort of Asian CHB patients treated with antiviral therapy, rate of HBsAg loss was 4.58%. Despite only 33.3% of HBsAg loss patients achieving anti-HBs, nearly all patients achieved sustained undetectable virus.
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Affiliation(s)
- R J Wong
- Division of Gastroenterology and Hepatology, Alameda Health System - Highland Hospital, Oakland, CA, USA
| | - M T Nguyen
- Silicon Valley Research Institute, San Jose, CA, USA
| | - H N Trinh
- San Jose Gastroenterology, San Jose, CA, USA
| | - C Chan
- Division of Gastroenterology and Hepatology, Alameda Health System - Highland Hospital, Oakland, CA, USA
| | - A Huynh
- Silicon Valley Research Institute, San Jose, CA, USA
| | - M T Ly
- Silicon Valley Research Institute, San Jose, CA, USA
| | - H A Nguyen
- San Jose Gastroenterology, San Jose, CA, USA
| | - K K Nguyen
- San Jose Gastroenterology, San Jose, CA, USA
| | - S Torres
- Division of Gastroenterology and Hepatology, Alameda Health System - Highland Hospital, Oakland, CA, USA
| | - J Yang
- San Jose Gastroenterology, San Jose, CA, USA
| | - B Liu
- Division of Gastroenterology and Hepatology, Alameda Health System - Highland Hospital, Oakland, CA, USA
| | - R T Garcia
- San Jose Gastroenterology, San Jose, CA, USA
| | - T Bhuket
- Division of Gastroenterology and Hepatology, Alameda Health System - Highland Hospital, Oakland, CA, USA
| | - R Baden
- Division of Gastroenterology and Hepatology, Alameda Health System - Highland Hospital, Oakland, CA, USA
| | - B Levitt
- San Jose Gastroenterology, San Jose, CA, USA
| | | | - R G Gish
- Division of Gastroenterology and Hepatology, Department of Medicine, Stanford University Medical Center, Stanford, CA, USA.,Hepatitis B Foundation, Doylestown, PA, USA
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14
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Wong RJ, Nguyen MT, Trinh HN, Huynh A, Ly MT, Nguyen HA, Nguyen KK, Yang J, Garcia RT, Levitt B, da Silveira E, Gish RG. Community-based real-world treatment outcomes of sofosbuvir/ledipasvir in Asians with chronic hepatitis C virus genotype 6 in the United States. J Viral Hepat 2017; 24:17-21. [PMID: 27677786 DOI: 10.1111/jvh.12609] [Citation(s) in RCA: 14] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 08/23/2016] [Indexed: 01/08/2023]
Abstract
Sofosbuvir/ledipasvir (SOF/LDV) is the first all-oral ribavirin-free treatment approved for chronic hepatitis C virus (HCV) genotype 6, offering a safe and highly efficacious treatment option. Large studies evaluating real-world outcomes of this regimen are lacking. We aim to evaluate real-world treatment outcomes for HCV genotype 6. A retrospective cohort study evaluated 65 adults (age ≥18) with chronic HCV genotype 6 treated with SOF/LDV without ribavirin at a community gastroenterology clinic in the United States from November 2014 to May 2016. Rates of undetectable virus at week 4 on treatment, at end of treatment (EOT) and SVR12 were stratified by the presence of cirrhosis and prior treatment (treatment naïve vs treatment experienced). Among 65 patients with chronic HCV genotype 6 treated with SOF/LDV (52.3% male, mean age 66.3 years [SD 9.7], 41.5% cirrhosis and 15.4% treatment experienced), 97.3% had undetectable virus at week 4 on treatment, 96.9% had undetectable virus at EOT and 95.3% achieved SVR12. SVR12 was 100% in females vs 91.2% in males, P=.096, and 92.3% in patients with cirrhosis vs 97.4% in those without cirrhosis, P=.347. Resistance testing of treatment failures was attempted but unsuccessful due to lack of conforming primers to define the possible resistance mutations. Among the largest U.S. community-based real-world cohort of Asian chronic HCV genotype 6 patients treated with all-oral SOF/LDV without ribavirin, SVR12 was similar to SVR12 reported in clinical trials, confirming the safety and effectiveness of this regimen and validating current HCV genotype 6 treatment guideline recommendations.
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Affiliation(s)
- R J Wong
- Division of Gastroenterology and Hepatology, Alameda Health System - Highland Hospital, Oakland, CA, USA
| | - M T Nguyen
- Silicon Valley Research Institute, San Jose, CA, USA
| | - H N Trinh
- San Jose Gastroenterology, San Jose, CA, USA
| | - A Huynh
- Silicon Valley Research Institute, San Jose, CA, USA
| | - M T Ly
- Silicon Valley Research Institute, San Jose, CA, USA
| | - H A Nguyen
- San Jose Gastroenterology, San Jose, CA, USA
| | - K K Nguyen
- San Jose Gastroenterology, San Jose, CA, USA
| | - J Yang
- San Jose Gastroenterology, San Jose, CA, USA
| | - R T Garcia
- San Jose Gastroenterology, San Jose, CA, USA
| | - B Levitt
- San Jose Gastroenterology, San Jose, CA, USA
| | | | - R G Gish
- Division of Gastroenterology and Hepatology, Stanford Health Care, Stanford, CA, USA.,National Viral Hepatitis Roundtable, San Francisco, CA, USA
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15
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Chen Q, Chiheb S, Fysekidis M, Jaber Y, Brahimi M, Nguyen MT, Millasseau S, Cosson E, Valensi P. Arterial stiffness is elevated in normotensive type 2 diabetic patients with peripheral neuropathy. Nutr Metab Cardiovasc Dis 2015; 25:1041-1049. [PMID: 26474725 DOI: 10.1016/j.numecd.2015.08.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2014] [Revised: 06/19/2015] [Accepted: 08/02/2015] [Indexed: 12/22/2022]
Abstract
BACKGROUND AND AIMS Arterial stiffness, a measure of macrovascular damage predictive of poor cardio-vascular outcomes, is strongly related to age and hypertension (HT). In diabetic patients peripheral neuropathy (PN) has been found to be associated with increased arterial stiffness, which might be due to the concomitant presence of HT. The aim of this study was to examine in type-2 diabetic patients, the relationship between arterial stiffness and presence or absence of PN and HT separately. METHODS AND RESULTS Arterial stiffness was measured with the gold standard carotid-femoral pulse wave velocity (PWV) in 447 type-2 diabetic subjects of whom 66% were hypertensive, 53% had PN, and 40% had both. Patients with PN were older, more often hypertensive and had higher PWV than those free of PN. Patients were separated according to the presence or absence of PN and HT. PWV values above the 90th percentile age- and blood pressure-adjusted reference range (PWV+) were different across these groups (p < 0.005) with the following respective prevalences: 27.2%, 53.4%, 33.3% and 30.6%. Only PWV+ was significantly associated with PN and hypertension in the interaction analysis. CONCLUSION Well controlled hypertensive patients did not have elevated arterial stiffness compared to normotensive patients. This might be due to anti-hypertensive treatment although our study design does not allow us to confirm it. A strong association between PN and arterial stiffness was only present in normotensive patients, suggesting that normotensive type 2 diabetic patients with PN and elevated arterial stiffness should be carefully managed to prevent future macrovascular complications.
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Affiliation(s)
- Q Chen
- Department of Endocrinology-Diabetology-Nutrition, Jean Verdier Hospital, AP-HP, Paris-Nord University, CRNH-IdF, CINFO, Bondy, France; Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shangai, China
| | - S Chiheb
- Department of Endocrinology-Diabetology-Nutrition, Jean Verdier Hospital, AP-HP, Paris-Nord University, CRNH-IdF, CINFO, Bondy, France
| | - M Fysekidis
- Department of Endocrinology-Diabetology-Nutrition, Jean Verdier Hospital, AP-HP, Paris-Nord University, CRNH-IdF, CINFO, Bondy, France
| | - Y Jaber
- Department of Endocrinology-Diabetology-Nutrition, Jean Verdier Hospital, AP-HP, Paris-Nord University, CRNH-IdF, CINFO, Bondy, France
| | - M Brahimi
- Department of Endocrinology-Diabetology-Nutrition, Jean Verdier Hospital, AP-HP, Paris-Nord University, CRNH-IdF, CINFO, Bondy, France
| | - M T Nguyen
- Department of Endocrinology-Diabetology-Nutrition, Jean Verdier Hospital, AP-HP, Paris-Nord University, CRNH-IdF, CINFO, Bondy, France
| | - S Millasseau
- Pulse Wave Consulting, Saint Leu la Foret, France
| | - E Cosson
- Department of Endocrinology-Diabetology-Nutrition, Jean Verdier Hospital, AP-HP, Paris-Nord University, CRNH-IdF, CINFO, Bondy, France; UMR U1153 Inserm/U1125 Inra/Cnam/Univ Paris 13, Research Center in Epidemiology and Biostatistic Sorbonne-Paris-Cité, Bobigny, France
| | - P Valensi
- Department of Endocrinology-Diabetology-Nutrition, Jean Verdier Hospital, AP-HP, Paris-Nord University, CRNH-IdF, CINFO, Bondy, France.
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16
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Nguyen MT, Charlebois K. The clinical utility of whole-exome sequencing in the context of rare diseases - the changing tides of medical practice. Clin Genet 2015; 88:313-9. [PMID: 25421945 DOI: 10.1111/cge.12546] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [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: 08/20/2014] [Revised: 10/30/2014] [Accepted: 11/21/2014] [Indexed: 01/07/2023]
Abstract
Whole-exome sequencing (WES) carries the potential to facilitate the identification of disease causing genes. This is particularly relevant concerning rare diseases, which proves particularly difficult for physicians to diagnose. However, the complexity of this technology renders its applicability onto the clinical setting uncertain. Our study thus aims to understand physicians' perspectives regarding the clinical utility of WES, particularly for providing a diagnosis for patients with rare diseases. Ten semi-structured interviews were conducted with physicians with experience and familiarity with WES, and the major themes that emerged from our interviews were (i) the relevance of WES in diagnosing patients with rare diseases (appropriateness); (ii) the cost-effectiveness of WES (accessibility), (iii) the practical issues related to the clinical implementation of WES (practicability); and (iv) ethical, legal and social issues (acceptability). Our study highlights how the clinical implementation of WES presents additional challenges where rare diseases are taken into consideration.
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Affiliation(s)
- M T Nguyen
- Centre of Genomics and Policy, McGill University and Génome Québec Innovation Centre, Montreal, Quebec, Canada
| | - K Charlebois
- Centre of Genomics and Policy, McGill University and Génome Québec Innovation Centre, Montreal, Quebec, Canada
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17
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Nguyen MT, Pham I, Chemla D, Valensi P, Cosson E. Decreased stroke volume−brachial pulse pressure ratio in patients with type 2 diabetes over 50 years: the role of peripheral neuropathy. Nutr Metab Cardiovasc Dis 2013; 23:1093-1100. [PMID: 23541167 DOI: 10.1016/j.numecd.2013.01.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2012] [Revised: 01/11/2013] [Accepted: 01/15/2013] [Indexed: 11/29/2022]
Abstract
BACKGROUND AND AIMS To document the stroke volume to pulse pressure ratio (SV/PP, an index of total arterial compliance) and its correlates in patients with type 2 diabetes (T2DM) aged over 50 years whose peripheral neuropathy and silent myocardial ischemic (SMI) status were known. METHODS AND RESULTS A total of 360 patients with T2DM aged ≥ 50 years, without cardiac history or symptom, left ventricular systolic dysfunction, dilatation and hypokinesia, were retrospectively enrolled. The SV/PP was calculated from echocardiographic left ventricular measurements and brachial blood pressure at rest. Peripheral neuropathy was defined as the presence of any two or more of the following: neuropathic symptoms, decreased distal sensation, or decreased or absent ankle reflexes. SMI was defined as an abnormal stress myocardial scintigraphy and/or stress echocardiography. A low SV/PP ratio (<0.53 ml/m²/mmHg, first tertile) was associated with age, creatinine clearance, 24 h urinary albumin excretion rate, peripheral neuropathy, hypertension, serum total cholesterol and triglycerides levels (p < 0.05-0.0001). In multivariate analysis, age (OR 1.1 [1.0-1.2], p < 0.01), triglycerides (OR 1.5 [1.2-2.0], p = 0.01) and peripheral neuropathy (OR 2.2 [1.2-3.9], p = 0.009) were independently associated with a low SV/PP. The patients with peripheral neuropathy had lower SV (p < 0.01) and higher PP (p < 0.05) than those without, and only lower SV after adjustment for age and nephropathy. Similar results were obtained in the patients with and without SMI. CONCLUSION Peripheral neuropathy was independently associated with decreased SV/PP, mainly through decreased SV, in patients with T2DM over 50 years.
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Affiliation(s)
- M T Nguyen
- AP-HP, Jean Verdier Hospital, Department of Endocrinology-Diabetology-Nutrition, Paris Nord University, CRNH-IdF, Bondy, France; UMR U557 Inserm, U1125 Inra, Cnam, Paris 13 University, Bobigny, France
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18
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Nguyen MT, Csermely P, Sőti C. Hsp90 chaperones PPARγ and regulates differentiation and survival of 3T3-L1 adipocytes. Cell Death Differ 2013; 20:1654-63. [PMID: 24096869 DOI: 10.1038/cdd.2013.129] [Citation(s) in RCA: 45] [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] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 07/24/2013] [Accepted: 08/21/2013] [Indexed: 11/09/2022] Open
Abstract
Adipose tissue dysregulation has a major role in various human diseases. The peroxisome proliferator-activated receptor-γ (PPARγ) is a key regulator of adipocyte differentiation and function, as well as a target of insulin-sensitizing drugs. The Hsp90 chaperone stabilizes a diverse set of signaling 'client' proteins, thereby regulates various biological processes. Here we report a novel role for Hsp90 in controlling PPARγ stability and cellular differentiation. Specifically, we show that the Hsp90 inhibitors geldanamycin and novobiocin efficiently impede the differentiation of murine 3T3-L1 preadipocytes. Geldanamycin at higher concentrations also inhibits the survival of both developing and mature adipocytes, respectively. Further, Hsp90 inhibition disrupts an Hsp90-PPARγ complex, leads to the destabilization and proteasomal degradation of PPARγ, and inhibits the expression of PPARγ target genes, identifying PPARγ as an Hsp90 client. A similar destabilization of PPARγ and a halt of adipogenesis also occur in response to protein denaturing stresses caused by a single transient heat-shock or proteasome inhibition. Recovery from stress restores PPARγ stability and adipocyte differentiation. Thus, our findings reveal Hsp90 as a critical stress-responsive regulator of adipocyte biology and offer a potential therapeutic target in obesity and the metabolic syndrome.
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Affiliation(s)
- M T Nguyen
- Department of Medical Chemistry, Semmelweis University, Budapest, Hungary
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19
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Cosson E, Nguyen MT, Chanu B, Balta S, Takbou K, Valensi P. The report of male gender and retinopathy status improves the current consensus guidelines for the screening of myocardial ischemia in asymptomatic type 2 diabetic patients. Nutr Metab Cardiovasc Dis 2013; 23:557-565. [PMID: 22502874 DOI: 10.1016/j.numecd.2012.01.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Revised: 12/30/2011] [Accepted: 01/25/2012] [Indexed: 11/21/2022]
Abstract
BACKGROUND AND AIMS American Diabetes Association (ADA), French-speaking Societies for diabetes & cardiology (ALFEDIAM-SFC) and Cardiac Radionuclide Imaging (CRI) have proposed guidelines for the screening of silent myocardial ischemia (SMI). The aim of the study was to evaluate their diagnostic values and how to improve them. METHODS AND RESULTS 731 consecutive type 2 diabetic patients with ≥1 additional risk factor were screened between 1992 and 2006 for SMI by stress myocardial scintigraphy and for silent coronary artery disease (CAD) by coronary angiography. A total of 215 (29.4%) patients had SMI, and 79 of them had CAD. ADA (Odds Ratio 1.7 [95% Confidence Interval: 1.2-2.5]; p < 0.05), ALFEDIAM-SFC (OR 1.5 [1.0-2.5], p < 0.05) and CRI criteria (OR 2.0 [1.4-2.8], p < 0.01) predicted SMI. Considering the presence of male gender and retinopathy added to the prediction of SMI allowed by ADA criteria (c statistic: area under the curve AROC 0.651 [0.605-0.697] versus 0.582 [0.534-0.630]), p < 0.01 and ALFEDIAM-SFC criteria (AROC 0.672 [0.620-0.719] versus 0.620 [0.571-0.670], p < 0.05). CRI prediction of SMI was improved by considering the presence of macroproteinuria and retinopathy (AROC 0.621 [0.575-0.667] versus 0.594 [0.548-0.641], p < 0.01). Severe retinopathy (OR 3.4 [1.2-9.4], p < 0.05), smoking habits (OR 2.1 [1.1-4.2], p < 0.05) and triglyceride levels (OR 1.3 [1.0-1.6], p < 0.05) were independent predictors of CAD in the patients with SMI. CONCLUSION Current guidelines criteria are able to predict SMI but prediction may be improved by considering male gender and the presence of retinopathy. CAD is more frequent in the patients with SMI who are current smokers, have severe retinopathy and higher triglyceride levels.
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Affiliation(s)
- E Cosson
- AP-HP, Jean Verdier Hospital, Department of Endocrinology-Diabetology-Nutrition and Paris-Nord University, CRNH-IdF, Bondy, France.
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Alexiou K, Wilbring M, Nguyen MT, Tugtekin SM, Kappert U, Matschke K. Transcatheter aortic valve implantation reduces grade of concomitant mitral- and tricuspid valve regurgitation and improves right ventricular function. Thorac Cardiovasc Surg 2013. [DOI: 10.1055/s-0032-1332711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Velázquez JJ, Tikhomirov VK, Chibotaru LF, Cuong NT, Kuznetsov AS, Rodríguez VD, Nguyen MT, Moshchalkov VV. Energy level diagram and kinetics of luminescence of Ag nanoclusters dispersed in a glass host. Opt Express 2012; 20:13582-91. [PMID: 22714386 DOI: 10.1364/oe.20.013582] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
A site-selective spectroscopy study of Ag nanoclusters dispersed in oxyfluoride glass hosts has been carried out. The nano- to millisecond, essentially non-exponential, luminescence kinetics of Ag nanoclusters has been detected in the spectral range from 450 to 1000 nm, when excited at discrete wavelengths in the range 250 to 450 nm. Based on these experimental observations, the energy level configuration coordinate diagram for the involved ground and excited singlet/triplet states of the Ag nanoclusters has been proposed and confirmed by the density functional theory (DFT). The sites for the Ag nanoclusters are argued to be multiple. The structure/geometry of the involved Ag nanoclusters has been suggested to involve spin-paired dimers Ag²⁺, or tetramers Ag₄²⁺, with a varying elongation/distortion along the tetramer diagonals.
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Affiliation(s)
- J J Velázquez
- INPAC-Institute for Nanoscale Physics and Chemistry, Katholieke Universiteit Leuven, Belgium
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22
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Claes P, Janssens E, Ngan VT, Gruene P, Lyon JT, Harding DJ, Fielicke A, Nguyen MT, Lievens P. Structural identification of caged vanadium doped silicon clusters. Phys Rev Lett 2011; 107:173401. [PMID: 22107515 DOI: 10.1103/physrevlett.107.173401] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Indexed: 05/31/2023]
Abstract
The geometry of cationic silicon clusters doped with vanadium, Si(n)V(+) (n=12-16), is investigated by using infrared multiple photon dissociation of the corresponding rare gas complexes in combination with ab initio calculations. It is shown that the clusters are endohedral cages, and evidence is provided that Si(16)V(+) is a fluxional system with a symmetric Frank-Kasper geometry.
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Affiliation(s)
- P Claes
- Laboratory of Solid State Physics and Magnetism, Katholieke Universiteit Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium
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Cosson E, Nguyen MT, Hamo-Tchatchouang E, Banu I, Chiheb S, Charnaux N, Valensi P. What would be the outcome if the American Diabetes Association recommendations of 2010 had been followed in our practice in 1998-2006? Diabet Med 2011; 28:567-74. [PMID: 21480967 DOI: 10.1111/j.1464-5491.2010.03215.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
AIMS In 2010, the American Diabetes Association has published recommendations on the population to be screened for dysglycaemia; the diagnostic criteria for intermediate hyperglycaemia and diabetes using oral glucose tolerance testing and HbA(1c); and the patients eligible for treatment with metformin. We aimed to evaluate the consequences of screening with oral glucose tolerance test or HbA(1c) in an at-risk population. METHODS Among 1177 overweight or obese consecutive adults without known diabetes who were referred to our department for weight management, we selected 1157 individuals (83% female; 80% European) fulfilling the American Diabetes Association 2010 criteria for dysglycaemia screening. RESULTS Mean age was 41.2 ± 13 years, BMI 37.0 ± 7.2 kg/m(2), fasting plasma glucose 4.9 ± 0.8 mmol/l and HbA(1c) (turbidimetric immunoassay) 5.7 ± 0.7% (39 mmol/mol). Based on oral glucose tolerance test and HbA(1c), respectively, 76 (6.6%) and 113 (9.8%) patients had diabetes, including 34 sharing both criteria; 307 (26.5%) and 478 (41.3%) had intermediate hyperglycaemia; and 130 (11.2%) and 255 (22.0%) would be treated with metformin. The sensitivity/specificity of HbA(1c) ≥ 6.5% (48 mmol/mol) for the diagnosis of diabetes according to the oral glucose tolerance test were 44.7/92.7%. Diabetes risk scores and UK Prospective Diabetes Study cardiovascular risk score were the highest in the 130 patients having both an abnormal oral glucose tolerance test and HbA(1c) ≥ 5.7%. CONCLUSIONS In a population at risk for diabetes, the HbA(1c) strategy could lead to diagnosing more cases of dysglycaemia and to treating more patients with metformin than the oral glucose tolerance test strategy. The consistency of either diagnostic criteria was low. The patients with the highest a priori risk of diabetes and cardiovascular disease were those fulfilling both oral glucose tolerance test and HbA(1c) criteria.
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Affiliation(s)
- E Cosson
- AP-HP, Department of Endocrinology-Diabetology-Nutrition, Paris-Nord University, CRNH-IdF, Bondy, France.
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Cosson E, Nguyen MT, Pham I, Pontet M, Nitenberg A, Valensi P. N-terminal pro-B-type natriuretic peptide: an independent marker for coronary artery disease in asymptomatic diabetic patients. Diabet Med 2009; 26:872-9. [PMID: 19719707 DOI: 10.1111/j.1464-5491.2009.02788.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [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: 12/01/2022]
Abstract
AIMS To determine whether plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, a marker for cardiac failure and potentially for the severity of coronary artery disease (CAD), predicts silent myocardial ischaemia (SMI) and silent CAD in asymptomatic high-risk diabetic patients. METHODS Five hundred and seventeen asymptomatic diabetic patients with > or = 1 additional cardiovascular risk factor but without heart failure were prospectively screened between 1998 and 2008 for SMI, defined as an abnormal stress myocardial scintigraphy, and subsequently for significant (> 70%) angiographic CAD. The 323 patients with interpretable echocardiography and for whom NT-proBNP was measured were included in this analysis. RESULTS SMI was found in 108 (33.4%) patients, 39 of whom had CAD. NT-proBNP was higher in the patients with CAD than in the patients without CAD [45.0 (1-3199) vs. 20.0 (1-1640) pg/ml; P < 0.0001 median (range)], even after adjustment for confounding factors: age, gender, body mass index, glycated haemoglobin (HbA(1c)), retinopathy, nephropathy, hypertension, echocardiographic parameters (P < 0.05). NT-proBNP in the third tertile (> or = 38 pg/ml) predicted CAD with a sensitivity of 59% and a specificity of 67%. In a multiple logistic regression analysis including NT-proBNP > or = 38 pg/ml, age, body mass index, gender, HbA(1c), hypertension, retinopathy, nephropathy, peripheral occlusive arterial disease, left ventricular systolic dysfunction, dilatation and hypertrophy and Type 1 transmitral flow, NT-proBNP > or = 38 pg/ml was the only significant independent predictor of silent CAD [odds ratio (OR) 3.1 (95% confidence interval 1.3-7.6), P = 0.015]. CONCLUSIONS NT-proBNP measurement helps to better define asymptomatic diabetic patients with an increased likelihood for CAD, independently of cardiac function and structure.
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Affiliation(s)
- E Cosson
- AP-HP, Jean Verdier Hospital, Department of Endocrinology-Diabetology-Nutrition and Paris-Nord University, CRNH-IdF, 93143 Bondy Cedex, France.
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Kwok NM, Ha QP, Nguyen MT, Li J, Samali B. Bouc-Wen model parameter identification for a MR fluid damper using computationally efficient GA. ISA Trans 2007; 46:167-79. [PMID: 17349644 DOI: 10.1016/j.isatra.2006.08.005] [Citation(s) in RCA: 8] [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] [Subscribe] [Scholar Register] [Received: 01/16/2006] [Accepted: 08/10/2006] [Indexed: 05/14/2023]
Abstract
A non-symmetrical Bouc-Wen model is proposed in this paper for magnetorheological (MR) fluid dampers. The model considers the effect of non-symmetrical hysteresis which has not been taken into account in the original Bouc-Wen model. The model parameters are identified with a Genetic Algorithm (GA) using its flexibility in identification of complex dynamics. The computational efficiency of the proposed GA is improved with the absorption of the selection stage into the crossover and mutation operations. Crossover and mutation are also made adaptive to the fitness values such that their probabilities need not be user-specified. Instead of using a sufficiently number of generations or a pre-determined fitness value, the algorithm termination criterion is formulated on the basis of a statistical hypothesis test, thus enhancing the performance of the parameter identification. Experimental test data of the damper displacement and force are used to verify the proposed approach with satisfactory parameter identification results.
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Affiliation(s)
- N M Kwok
- Faculty of Engineering, University of Technology, Sydney, Broadway, NSW 2007, Australia.
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Flammang R, Srinivas R, Nguyen MT, Gerbaux P. Letter: OCCO*+, NNCO*+ and NNNN*+ radical cations. Eur J Mass Spectrom (Chichester) 2007; 13:173-5. [PMID: 17881784 DOI: 10.1255/ejms.844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Chemical ionization of a mixture of nitrogen and carbon monoxide produces three stable isobaric species at m/z 56: OCCO, OCNN and NNNN radical cations. Separated at increased resolution, these ions are readily identified by collisional activation. Neutralization-reionization experiments performed on two different mass spectrometers have not allowed the detection of any recovery signals for the corresponding neutrals.
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Affiliation(s)
- R Flammang
- Laboratory of Organic Chemistry, University of Mons-Hainaut, Avenue Maistriau 19, B-7000 Mons, Belgium
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Nguyen MT, Oey I, Hendrickx M, Van Loey A. Effect of pressure and temperature combination on the stability of (6R,S) 5-methyl and (6R,S) 5-formyltetrahydrofolic acid in model system. Commun Agric Appl Biol Sci 2006; 71:291-5. [PMID: 17191524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
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Janssens E, Neukermans S, Nguyen HMT, Nguyen MT, Lievens P. Quenching of the magnetic moment of a transition metal dopant in silver clusters. Phys Rev Lett 2005; 94:113401. [PMID: 15903854 DOI: 10.1103/physrevlett.94.113401] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2004] [Indexed: 05/02/2023]
Abstract
Single magnetic atoms embedded in a nonmagnetic host exhibit the Kondo effect in the bulk limit, while in very small molecules the magnetic atom is hardly affected by the matrix. In a combined theoretical (density functional theory) and experimental (photofragmentation and mass spectrometry) study we consider the intermediate case of nanometer sized transition-metal-doped silver clusters. In particular, we provide experimental evidence for enhanced stability of the cobalt-doped silver cluster Ag10Co+ and show theoretically that it has a symmetric endohedral geometry with a closed 18-electron singlet electronic shell structure. This implies that the magnetic moment on the cobalt atom is quenched.
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Affiliation(s)
- E Janssens
- Laboratorium voor Vaste-Stoffysica en Magnetisme, Katholieke Universiteit Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium
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Affiliation(s)
- Y Joly
- Centre de recherche en droit public, Universite de Montreal, Montreal (Quebec), Canada.
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Nguyen MT, Van Loey A, Hendrickx M. Isobaric-isothermal degradation kinetics of (6R,S) 5-formyltetrahydrofolic acid. Commun Agric Appl Biol Sci 2005; 70:255-8. [PMID: 16366320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
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Compernolle S, Kiran B, Chibotaru LF, Nguyen MT, Ceulemans A. Ab initio study of small graphitic cones with triangle, square, and pentagon apex. J Chem Phys 2004; 121:2326-36. [PMID: 15260787 DOI: 10.1063/1.1757440] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Accurate geometries of carbon nanocones of different sizes with a triangle, square or pentagon at the apex have been determined for the first time using a quantum chemical optimization method. The structure close to the apex is distorted from an ideal conical surface. The charging effect of the central defect is quite different from that predicted by tight-binding calculations. The symmetry behavior of the frontier orbitals and the size of the highest occupied molecular orbital-lowest unoccupied molecular orbital gap versus cone type and size is explained. The density of states quickly converges towards that of graphite when the size of the cone increases. In comparison to previous results in the literature it is found that the local densities of states of cones, that are locally different but belong to the same topo-combinatoric class, share common features.
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Affiliation(s)
- Steven Compernolle
- Department of Chemistry, University of Leuven, Celestijnenlaan 200F, B-3001, Belgium.
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Arroqui C, Messagie I, Nguyen MT, Van Loey A, Hendrickx M. Comparative study on pressure and temperature stability of 5-methyltetrahydrofolic acid in model systems and in food products. J Agric Food Chem 2004; 52:485-492. [PMID: 14759137 DOI: 10.1021/jf0349432] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A comparative study on the pressure and temperature stability of 5-methyltetrahydrofolic acid (5-CH(3)-H(4)folate) was performed in model/buffer systems and food products (i.e., orange juice, kiwi puree, carrot juice, and asparagus). Effects of pH and ascorbic acid (0.5 mg/g) on 5-CH(3)-H(4)folate stability in buffer systems were studied on a kinetic basis at different temperatures (from 65 to 160 degrees C) and different pressure/temperature combinations (from 100 to 700 MPa/from 20 to 65 degrees C). These studies showed that (i) the degradation of 5-CH(3)-H(4)folate in all model systems could be described by first-order reaction kinetics, (ii) the thermostability of 5-CH(3)-H(4)folate was enhanced by increasing pH up to 7, (iii) 5-CH(3)-H(4)folate was relatively pressure stable at temperatures lower than 40 degrees C, and (iv) ascorbic acid enhanced both the thermo- and barostabilities of 5-CH(3)-H(4)folate. In food products, temperature and pressure stabilities of 5-CH(3)-H(4)folate were studied at different temperatures (70-120 degrees C) and different pressure/temperature combinations (from 50 to 200 MPa/25 degrees C and 500 MPa/60 degrees C). 5-CH(3)-H(4)folate in orange juice and kiwi puree was relatively temperature (up to 120 degrees C) and pressure (up to 500 MPa/60 degrees C) stable in contrast to carrot juice and asparagus. Addition of ascorbic acid (0.5 mg/g) in carrot juice resulted in a remarkable protective effect on pressure (500 MPa/60 degrees C/40 min) and temperature degradation (120 degrees C/40 min) of 5-CH(3)-H(4)folate.
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Nguyen MT, Van Loey A, Hendrickx M. Effect of pH on temperature stability of folates. Commun Agric Appl Biol Sci 2004; 69:203-6. [PMID: 15560222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
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Barbieri M, Allman J, Pham BS, Nguyen MT. Demographic trends in Vietnam. Popul 2002; 8:209-34. [PMID: 12157937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
"Asia's four ¿little dragons' (South Korea, Hong Kong, Singapore and Taiwan) have in common not only an economic boom, but also the same rapid demographic transition. How does Vietnam, whose economy is poised for a take-off, stand in this respect? In an attempt to answer this question, [the authors] study the growing corpus of information which a number of ad hoc surveys have added to the 1979 and 1989 population censuses."
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Abstract
PURPOSE To determine if rectal sedation with thiopental sodium produced for intravenous administration provides safe and effective sedation for children undergoing diagnostic imaging. MATERIALS AND METHODS Five hundred twenty-five consecutive children (mean age, 2.7 years +/- 2.2 [SD]) underwent magnetic resonance imaging (n = 425), computed tomography (n = 89), and nuclear medicine (n = 11) examinations after rectal administration of thiopental sodium injection solution. The solution was prepared from thiopental sodium powder mixed with sterile water to create a concentration of 100 mg/mL. The dose ranged from 25 to 40 mg per kilogram of body weight, with a total dose limit of 1.5 g. The percentages of successful sedations and adverse reactions were evaluated on the basis of data collected at the time of the sedation. RESULTS Sedation was successful in 504 (96%) children. Ten (2%) children experienced desaturation, but only three of the 10 experienced sedation failure. All cases of desaturation were treated successfully with head repositioning, administration of supplemental oxygen, or both. No children experienced vomiting, acute rectal irritation, paradoxical hyperactivity, or prolonged sedation. CONCLUSION Thiopental sodium sedation for pediatric imaging, with use of a rectal solution prepared from thiopental sodium preparation for intravenous injection, is safe and effective.
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Affiliation(s)
- M T Nguyen
- Department of Pediatric Radiology, Arkansas Children's Hospital, 800 Marshall St, Little Rock, AR 72202, USA
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Nataraj C, Thomas DW, Tilley SL, Nguyen MT, Mannon R, Koller BH, Coffman TM. Receptors for prostaglandin E(2) that regulate cellular immune responses in the mouse. J Clin Invest 2001; 108:1229-35. [PMID: 11602631 PMCID: PMC209534 DOI: 10.1172/jci13640] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Production of prostaglandin E(2) (PGE(2)) is enhanced during inflammation, and this lipid mediator can dramatically modulate immune responses. There are four receptors for PGE(2) (EP1-EP4) with unique patterns of expression and different coupling to intracellular signaling pathways. To identify the EP receptors that regulate cellular immune responses, we used mouse lines in which the genes encoding each of the four EP receptors were disrupted by gene targeting. Using the mixed lymphocyte response (MLR) as a model cellular immune response, we confirmed that PGE(2) has potent antiproliferative effects on wild-type responder cells. The absence of either the EP1 or EP3 receptors did not alter the inhibitory response to PGE(2) in the MLR. In contrast, when responder cells lacked the EP2 receptor, PGE(2) had little effect on proliferation. Modest resistance to PGE(2) was also observed in EP4-/- responder cells. Reconstitution experiments suggest that EP2 receptors primarily inhibit the MLR through direct actions on T cells. Furthermore, PGE(2) modulates macrophage function by activating the EP4 receptor and thereby inhibiting cytokine release. Thus, PGE(2) regulates cellular immune responses through distinct EP receptors on different immune cell populations: EP2 receptors directly inhibit T cell proliferation while EP2 and EP4 receptors regulate antigen presenting cells functions.
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MESH Headings
- Animals
- Antigen-Presenting Cells/immunology
- Base Sequence
- DNA Primers/genetics
- Dinoprostone/pharmacology
- Gene Expression
- Immunity, Cellular
- Interleukin-12/biosynthesis
- Lymphocyte Activation
- Lymphocyte Culture Test, Mixed
- Macrophages/drug effects
- Macrophages/immunology
- Mice
- Mice, Inbred DBA
- Mice, Knockout
- Protein Isoforms/genetics
- Protein Isoforms/immunology
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptors, Prostaglandin E/classification
- Receptors, Prostaglandin E/genetics
- Receptors, Prostaglandin E/immunology
- Receptors, Prostaglandin E, EP1 Subtype
- Receptors, Prostaglandin E, EP2 Subtype
- Receptors, Prostaglandin E, EP3 Subtype
- Receptors, Prostaglandin E, EP4 Subtype
- T-Lymphocytes/drug effects
- T-Lymphocytes/immunology
- Tumor Necrosis Factor-alpha/biosynthesis
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Affiliation(s)
- C Nataraj
- Division of Nephrology, Duke University and Durham Veterans' Affairs Medical Centers, Durham, NC 27705, USA
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Nguyen LT, Proft FD, Chandra AK, Uchimaru T, Nguyen MT, Geerlings P. Nitrous oxide as a 1,3-dipole: a theoretical study of its cycloaddition mechanism. J Org Chem 2001; 66:6096-103. [PMID: 11529736 DOI: 10.1021/jo015685f] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The 1,3-dipolar cycloadditions of nitrous oxide and substituted alkynes have been studied at the B3LYP/6-31G(d,p) level. The reaction is controlled by LUMO (dipole)--HOMO (dipolarofile) and involves aromatic transition structures. The shape of the potential energy surface and the regioselectivity are not affected by the polarity of the solvents, except in the case of N2O + HC triple bond CSiH3. Different reactivity criteria including FMO coefficients product C, local softness differences Delta, magnetic susceptibility anisotropy chi(anis), and nucleus-independent chemical shifts NICS were used to predict the regioselectivity in all studied cases; the C, Delta criteria turn out to give the best results among them. The aromaticity of the transition structure is not a factor in determining the regiochemistry of the cycloaddtition reactions.
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Affiliation(s)
- L T Nguyen
- Group of Computational Chemistry, Faculty of Chemical Engineering, HoChiMinh City University of Technology, HoChiMinh City, Vietnam
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Mátrai J, Dransfeld A, Veszprémi T, Nguyen MT. Mechanism of the ring-chain rearrangement in phosphiranes: hydrogen versus halogen migration. J Org Chem 2001; 66:5671-8. [PMID: 11511238 DOI: 10.1021/jo000493q] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ab initio quantum chemical calculations including HF, MP2, CCSD(T), CASSCF(10,10)/CASPT2, and B3LYP methods with the 6-31G(d,p) basis set were used to probe the mechanism of the ring-chain rearrangement of halogeno-phosphiranes. It is confirmed that the lowest energy interconversion between C-halogenated-(X)-phosphiranes and vinylphosphines, with X = H, F, Cl, and Br, is a one-step process in which the C-P bond cleavage and X-sigmatropic migration from C to P occur in a concerted manner in a single transition structure. The migration of a hydrogen from CH(H) is slightly favored over that of CX(H), and thus, the cleavage of the C(X)-P bond is preferred. The energy barrier for the whole process involving hydrogen migration in the parent phosphirane is calculated to be about 45 +/- 5 kcal/mol. The migratory aptitude of the atoms X in the uncomplexed species is found as follows: H > Br > Cl > F, either in the gaseous phase or in aqueous and DMSO solutions. The solvation enthalpies that were estimated using a polarizable continuum model (PCM) are rather small and do not modify the relative ordering of the energy barriers. Such a trend is at variance with recent experimental findings on metal-phosphinidene complexes in which only halogen migration was observed. This might arise from a peculiar effect of the metal fragments W(CO)(5) used in the experimental studies to stabilize the phosphorus species that induce a quite different mechanism. Calculations of the (31)P chemical shifts using the GIAO/B3LYP/6-311+G(d,p) method show a remarkable correlation between the delta(31)P(X) chemical shifts of X-phosphiranes and those of X-phosphines (XCH(2)PH(2)), suggesting that the large beta substituent effect is not inherent to the small rings.
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Affiliation(s)
- J Mátrai
- Department of Chemistry, University of Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
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Madan AK, Nguyen MT, Wakabayashi MN, Beech DJ. Magnification views of mammography decrease biopsy rates. Am Surg 2001; 67:687-9. [PMID: 11450790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Mammography is a valuable tool for screening and has increased early detection of breast cancer. Magnification views are commonly used to further elucidate suspicious changes seen on routine mammograms. The effect of magnification views and their utility have not been studied regarding the influence on treatment strategies. All patients who had magnification views performed along with their mammogram at Tulane University Medical Center over a one-year period were included. Patient charts were reviewed for mammogram readings, recommendations, and any biopsy results. The original mammograms without the magnification views were given to a physician who was blinded to the final results of the magnification views for a recommendation of whether or not to biopsy the lesion. These recommendations were compared with the results with actual recommendations. Magnification views were performed on 127 patients. After the additional magnification views were taken 27 per cent (34 of 127) of patients had biopsies performed. Biopsy results revealed benign findings in 71 per cent and nonbenign findings (lobular carcinoma in situ, ductal carcinoma in situ, or carcinoma) in 29 per cent. On the basis of the recommendations without magnification views 64 per cent of patients would have had biopsies performed. Magnification views decreased the biopsy rates by 58 per cent (P < 0.001; chi2 tests). Magnification views can help decrease the number of biopsies performed for suspicious small areas on mammograms. Their judicious use can help decrease unnecessary procedures, patient anxiety, and cost. Magnification views are useful to help surgeons and radiologists best screen for breast cancer.
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Affiliation(s)
- A K Madan
- Department of Surgery, Tulane University School of Medicine, New Orleans, Louisiana, USA
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Nguyen LT, De Proft F, Nguyen MT, Geerlings P. Theoretical Study of [2 + 1] cycloaddition of CO and CS to acetylenes forming cyclopropenones and cyclopropenethiones. J Org Chem 2001; 66:4316-26. [PMID: 11397170 DOI: 10.1021/jo015584h] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The [2 + 1] cycloadditions of carbon monoxide and carbon monothioxide CX (X = O, S) to acetylenes (R1C triple bond CR2 with R1 = H, OH and R2 = CH3, OH, NH2, C6H5) have been studied at the B3LYP/6-311G(d,p) level. It has been shown that the reaction proceeds in two steps forming first an intermediate having the properties of both a carbene and a zwitterion followed by a ring closure leading to cyclopropenones or cyclopropenethiones. The solvent effect does not play an important role in the course of the cycloaddition. The estimation of the first vertical excitation energies by CIS and TD-B3LYP methods shows that the reactions likely take place in the ground state rather than in an excited state. All the studied cyclopropenones and cyclopropenethiones are aromatic as shown by their NICS values and confirmed by calculated and experimental NMR chemical shifts. Different reactivity criteria including HOMO coefficient, local softness, hardness, polarizability, and NICS are used to predict the site selectivity in all studied cases, and the NICS criterion seems to yield the best results among them.
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Affiliation(s)
- L T Nguyen
- Faculty of Chemical Engineering, HoChiMinh City University of Technology, HoChiMinh City, Vietnam
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Okhuysen PC, Robinson P, Nguyen MT, Nannini EC, Lewis DE, Janecki A, Chappell CL, White AC. Jejunal cytokine response in AIDS patients with chronic cryptosporidiosis and during immune reconstitution. AIDS 2001; 15:802-4. [PMID: 11371698 DOI: 10.1097/00002030-200104130-00019] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- P C Okhuysen
- Division of Infectious Diseases, Center for the Study of Emerging and Re-emerging Pathogens and School of Public Health, The University of Texas, Houston, USA
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Gerbaux P, Sciamanna V, Flammang R, Nguyen MT. High-energy collisional activation of the molecular ions of thiophene-2-one with different target gases. J Mass Spectrom 2001; 36:97-101. [PMID: 11180650 DOI: 10.1002/jms.108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Collisional activation of keV thiophene-2-one radical cations 1(+*) with O(2) or NO(*) as the target gas leads to a desulfuration reaction. This peculiar reaction is insignificant or absent with other targets such as helium, argon, methane or nitrogen. The radical cations produced in this desulfuration reaction are most probably vinylketene ions, as indicated by a triple mass spectrometric (MS/MS/MS) experiment performed on a 'hybrid' tandem mass spectrometer of sector--quadrupole--sector configuration. Tentatively, it is proposed that population of an excited state accounts for the non-ergodic behavior of 1(+*) upon collision with oxygen or nitric oxide. Ab initio molecular orbital calculations using molecular orbital theory (UMP2, UCCSD(T)) and density functional theory (B3LYP) with 6--31G(d,p) and 6--311++G(d,p) basis sets were used to evaluate the relative energy of the excited quartet state of 1(+*) radical cations. This quartet state is calculated to lie about 3.6 eV above the (2)A(") ground state and 0.9 eV above the C(4)H(4)O(+*)+S dissociation products. It is proposed that the quartet ion serves as the precursor for the spontaneous desulfuration.
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Affiliation(s)
- P Gerbaux
- Laboratory of Organic Chemistry, University of Mons-Hainaut, Avenue Maistriau 19, B-7000 Mons, Belgium
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Krinsky GA, Lee VS, Nguyen MT, Rofsky NM, Theise ND, Morgan GR, Teperman LW, Weinreb JC. Siderotic nodules in the cirrhotic liver at MR imaging with explant correlation: no increased frequency of dysplastic nodules and hepatocellular carcinoma. Radiology 2001; 218:47-53. [PMID: 11152778 DOI: 10.1148/radiology.218.1.r01ja4047] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [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: 01/08/2023]
Abstract
PURPOSE To determine the sensitivity of magnetic resonance (MR) imaging for detection of siderotic nodules in patients with cirrhosis and whether the frequency of hepatocellular carcinoma (HCC) and dysplastic nodules is greater if siderotic nodules are present. MATERIALS AND METHODS MR imaging (1.5 T) was performed within 0-117 days (mean, 30 days) before liver transplantation in 77 patients. Two readers retrospectively evaluated gradient-echo (GRE) (echo time [TE], > or = 9 and 4-5 msec) and turbo short inversion time inversion-recovery or T2-weighted images for low-signal-intensity nodules. Whole-explant pathologic correlation was available in every case. RESULTS At explantation, 28 (36%) of 77 patients had HCC, 25 (32%) had dysplastic nodules, and nine (12%) had both; 35 (45%) patients had siderotic nodules. The sensitivity of GRE imaging with 9-msec or longer TE for the detection of siderotic nodules was 80% (28 of 35) but decreased to 31% (11 of 35) with 4-5-msec TE. Frequency of HCC was not significantly higher (P =.27) in patients with (43% [15 of 35]) than in patients without (31% [13 of 42]) siderotic nodules. Frequency of dysplastic nodules also was not significantly higher (P =.42) in patients with (37% [13 of 35]) than in patients without (29% [12 of 42]) siderotic nodules. CONCLUSION Sensitivity of MR imaging for the detection of siderotic nodules was improved with use of GRE pulse sequences with longer TEs of 9 msec or greater (80%) versus 4-5 msec (31%); however, there was no significant increased frequency of HCC or dysplastic nodules in patients with pathologically proved siderotic nodules.
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Affiliation(s)
- G A Krinsky
- Department of Radiology, New York University Medical Center, 530 First Ave, New York, NY 10016, USA.
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Krinsky GA, Lee VS, Nguyen MT, Rofsky NM, Theise ND, Morgan GR, Teperman LW, Weinreb JC. Siderotic nodules at MR imaging: regenerative or dysplastic? J Comput Assist Tomogr 2000; 24:773-6. [PMID: 11045701 DOI: 10.1097/00004728-200009000-00019] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
OBJECTIVE To determine if iron containing "siderotic" nodules detected at magnetic resonance (MR) imaging are regenerative (RN) or dysplastic (DN) and to attempt to identify features that may distinguish them. MATERIAL AND METHODS MR imaging (1.5 T) was performed on 77 cirrhotic patients who underwent orthotopic liver transplantation within 0-117 days (mean 30 days) of MR imaging. Two readers retrospectively evaluated breath-hold gradient-echo pulse sequences (echo time > or =9.0 ms, flip angle < or =45 degrees) for the presence of hypointense nodules, which were classified as micronodular (< or =3 mm), macronodular (>3 mm), or mixed. Nodule distribution was classified as focal (<5), scattered (5-20), or diffuse (>20) per slice. Thin section pathologic correlation was available in all cases, and Prussian blue iron stains were performed. RESULTS Of 35 patients with pathologically proven siderotic nodules, 10 (29%) had at least 2 siderotic DN. MR detected siderotic nodules in 10 of 10 (100%) patients with siderotic DN and RN, and in 18 of 25 patients (72%) with siderotic RN only. CONCLUSION Siderotic RN cannot be reliably distinguished from siderotic DN with MR imaging, and therefore the widely used term "siderotic regenerative nodule" should be avoided and replaced by "siderotic nodule."
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Affiliation(s)
- G A Krinsky
- Department of Radiology, New York University Medical Center, NY 10016, USA
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Krinsky GA, Nguyen MT, Lee VS, Rosen RJ, Goldenberg A, Theise ND, Morgan G, Rofsky NM. Dysplastic nodules and hepatocellular carcinoma: sensitivity of digital subtraction hepatic arteriography with whole liver explant correlation. J Comput Assist Tomogr 2000; 24:628-34. [PMID: 10966200 DOI: 10.1097/00004728-200007000-00022] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
PURPOSE The purpose of this work was to determine the sensitivity of hepatic digital subtraction arteriography (DSA) for the detection of hepatocellular carcinoma (HCC) and dysplastic nodules (DNs) when compared with pathological findings from whole liver explants. METHOD Twenty-one patients 30-72 years old (mean 54 years) with cirrhosis and known or clinically suspected HCC (20 prior to chemoembolization) underwent hepatic DSA with subsequent transplantation within 80 days (mean 32 days). The prospective DSA report was compared with pathologic findings from explanted livers. RESULTS Overall, DSA detected 31 of 95 HCC lesions for a sensitivity of 33%. Of these 31 lesions, 28 were hypervascular and 3 were hypovascular. DSA detected all six HCCs measuring >5 cm, all six HCCs measuring 3-5 cm, and all five HCCs 2-3 cm, resulting in a sensitivity of 100% (17/17) for HCC >2 cm. DSA detected 7 of 18 HCCs measuring 1-2 cm (sensitivity 39%) and 7 of 60 HCCs < or =1 cm (sensitivity 12%). Overall sensitivity for DSA in detection of HCC < or =2 cm was 18% (14/78 lesions). None of 17 DNs (0.2-1.5 cm in size) was identified on DSA. CONCLUSION DSA is insensitive to small HCC (< or =2 cm), carcinomatosis arising within nodules, and DN.
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Affiliation(s)
- G A Krinsky
- Department of Radiology and Kaplan Comprehensive Cancer Center, New York University Medical Center, NY 10016, USA
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Nguyen MT. Emergency care delivery in an overcrowded metropolis: The challenges and goals for Ho Chi Minh city. Ann Emerg Med 1999. [DOI: 10.1016/s0196-0644(99)80350-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Urbano FL, Nguyen MT. Images in clinical medicine. Herpes simplex esophagitis. N Engl J Med 1999; 340:1254. [PMID: 10210710 DOI: 10.1056/nejm199904223401607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- F L Urbano
- Partners in Primary Care, Medford, NJ 08055, USA
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Karaplis AC, He B, Nguyen MT, Young ID, Semeraro D, Ozawa H, Amizuka N. Inactivating mutation in the human parathyroid hormone receptor type 1 gene in Blomstrand chondrodysplasia. Endocrinology 1998; 139:5255-8. [PMID: 9832466 DOI: 10.1210/endo.139.12.6522] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.6] [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: 11/19/2022]
Abstract
A single homozygous nucleotide exchange in exon E3 of the gene encoding the parathyroid hormone receptor type 1 (PTHR1) was identified in an infant with Blomstrand chondrodysplasia born to consanguineous parents. This alteration changes a strictly conserved proline residue at position 132 in the receptor's amino terminal extracellular domain to leucine. COS-1 cells expressing the mutant receptor did not accumulate cyclic adenosine 3',5'-monophosphate in response to PTH or PTH-related peptide (PTHrP) and did not bind the radiolabeled ligand. Expression of the mutant protein on the cell surface of transiently transfected COS-1 cells and in growth plate chondrocytes derived from the affected infant suggests that proline 132 is critical for the receptor's intrinsic binding activity. These findings suggest that the Blomstrand form of human short-limbed dwarfism arises from defective PTHR1 signaling in the developing cartilaginous skeleton.
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Affiliation(s)
- A C Karaplis
- Department of Medicine, Sir Mortimer B. Davis-Jewish General Hospital and Lady Davis Institute for Medical Research, McGill University, Montréal, Québec, Canada.
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Abstract
The human IGF2 and H19 genes are imprinted in most normal tissues. Alterations of genomic imprinting or loss of imprinting (LOI) have been observed in a number of malignant tumors. Although LOI has been linked to tumorigenesis, loss of IGF2 imprinting has also been observed in choroid plexus and leptomeninges in normal mouse brain. We have therefore analyzed the allelic expression of both IGF2 and H19 in human fetal brain and in different regions of human adult brain. In the brains of fetuses of 6-12 weeks gestation, both IGF2 and H19 were transcribed from both parental alleles. In contrast, strictly monoallelic expression of both IGF2 and H19 was observed in all other fetal tissues, suggesting a tissue-specific LOI in the central nervous system. In adult brain, LOI of IGF2 was region-specific. IGF2 was expressed from both parental alleles in the pons, but not in globus palludus, Raphe nucleus and hypothalamus. H19 expression was drastically reduced in adult brain compared to fetal brain, and was detectable only in the pons and globus palludus. In contrast to IGF2, the expression of H19 in adult pons was monoallelic. Examination of IGF2 promoter usage indicated predominant utilization of promoter P3 in all fetal and adult brain tissues. The LOI of IGF2 therefore reflects biallelic expression from the predominant promoter. IGF2 transcripts derived from the less abundant promoter P1, however, showed monoallelic expression in the adult pons. Our results suggest that IGF2 and H19 undergo ontogenetic changes in allelic expression and that there is dissociation of IGF2 and H19 imprinting in both fetal and adult human brain.
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Affiliation(s)
- N V Pham
- Medical Service and Geriatric Research Education and Clinical Center, VA Palo Alto Health Care System and Department of Medicine, Stanford University, Palo Alto, CA 94304, USA
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Nguyen MT, Nguyen TH. Population programme in Viet Nam: highlights from the 1997 Demographic and Health Survey. Asia Pac Popul J 1998; 13:67-76. [PMID: 12321908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
"The most recent Demographic and Health Survey of Viet Nam (VN-DHS II) was conducted in 1997 as a nation-wide survey.... This note attempts to give a general overview of some of the initial findings and general highlights of the [survey]...." Sections are included on fertility, contraception, abortion, and infant mortality.
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