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Bing R, Deutsch MA, Sellers SL, Corral CA, Andrews JPM, van Beek EJR, Bleiziffer S, Burchert W, Clark T, Dey D, Friedrichs K, Gummert JF, Koglin N, Leipsic JA, Lindner O, MacAskill MG, Milting H, Pessotto R, Preuss R, Raftis JB, Rudolph TK, Rudolph V, Slomka P, Stephens AW, Tavares A, Tzolos E, Weir N, White AC, Williams MC, Zabel R, Dweck MR, Hugenberg V, Newby DE. 18F-GP1 Positron Emission Tomography and Bioprosthetic Aortic Valve Thrombus. JACC Cardiovasc Imaging 2022; 15:1107-1120. [PMID: 35033495 DOI: 10.1016/j.jcmg.2021.11.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 11/12/2021] [Accepted: 11/16/2021] [Indexed: 10/19/2022]
Abstract
BACKGROUND Bioprosthetic valve thrombosis may have implications for valve function and durability. OBJECTIVES Using a novel glycoprotein IIb/IIIa receptor radiotracer 18F-GP1, we investigated whether positron emission tomography (PET)-computed tomography (CT) could detect thrombus formation on bioprosthetic aortic valves. METHODS Ex vivo experiments were performed on human platelets and explanted bioprosthetic aortic valves. In a prospective cross-sectional study, patients with either bioprosthetic or normal native aortic valves underwent echocardiography, CT angiography, and 18F-GP1 PET-CT. RESULTS Flow cytometric analysis, histology, immunohistochemistry, and autoradiography demonstrated selective binding of 18F-GP1 to activated platelet glycoprotein IIb/IIIa receptors and thrombus adherent to prosthetic valves. In total, 75 participants were recruited: 53 with bioprosthetic valves (median time from implantation 37 months [IQR: 12-80 months]) and 22 with normal native aortic valves. Three participants had obstructive valve thrombosis, and a further 3 participants had asymptomatic hypoattenuated leaflet thickening on CT angiography. All bioprosthetic valves, but none of the native aortic valves, demonstrated focal 18F-GP1 uptake on the valve leaflets: median maximum target-to-background ratio 2.81 (IQR: 2.29-3.48) vs 1.43 (IQR: 1.28-1.53) (P < 0.001). Higher 18F-GP1 uptake was independently associated with duration of valve implantation and hypoattenuated leaflet thickening. All 3 participants with obstructive valve thrombosis were anticoagulated for 3 months, leading to resolution of their symptoms, improvement in mean valve gradients, and a reduction in 18F-GP1 uptake. CONCLUSIONS Adherence of activated platelets is a common and sustained finding on bioprosthetic aortic valves. 18F-GP1 uptake is higher in the presence of thrombus, regresses with anticoagulation, and has potential use as an adjunctive clinical tool. (18F-GP1 PET-CT to Detect Bioprosthetic Aortic Valve Thrombosis; NCT04073875).
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Affiliation(s)
- Rong Bing
- BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom.
| | - Marcus-André Deutsch
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Center North Rhine-Westphalia, University Hospital Ruhr-University Bochum, Bad Oeynhausen, Germany.
| | - Stephanie L Sellers
- Department of Radiology and Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Carlos Alcaide Corral
- BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Jack P M Andrews
- BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Edwin J R van Beek
- BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom; Edinburgh Imaging, Queen's Medical Research Institute, Edinburgh, United Kingdom
| | - Sabine Bleiziffer
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Center North Rhine-Westphalia, University Hospital Ruhr-University Bochum, Bad Oeynhausen, Germany
| | - Wolfgang Burchert
- Institute of Radiology, Nuclear Medicine and Molecular Imaging, Heart and Diabetes Center North Rhine-Westphalia, University Hospital Ruhr-University Bochum, Bad Oeynhausen, Germany
| | - Tim Clark
- Edinburgh Imaging, Queen's Medical Research Institute, Edinburgh, United Kingdom
| | - Damini Dey
- Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, USA
| | - Kai Friedrichs
- Department of General and Interventional Cardiology/Angiology, Heart and Diabetes Center North Rhine-Westphalia, University Hospital Ruhr-University Bochum, Bad Oeynhausen, Germany
| | - Jan F Gummert
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Center North Rhine-Westphalia, University Hospital Ruhr-University Bochum, Bad Oeynhausen, Germany
| | | | - Jonathon A Leipsic
- Department of Radiology and Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Oliver Lindner
- Institute of Radiology, Nuclear Medicine and Molecular Imaging, Heart and Diabetes Center North Rhine-Westphalia, University Hospital Ruhr-University Bochum, Bad Oeynhausen, Germany
| | - Mark G MacAskill
- BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Hendrik Milting
- Erich and Hanna Klessmann Institute for Cardiovascular Research and Development, Heart and Diabetes Center North Rhine-Westphalia, University Hospital Ruhr-University Bochum, Bad Oeynhausen, Germany
| | - Renzo Pessotto
- Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, United Kingdom
| | - Rainer Preuss
- Institute of Radiology, Nuclear Medicine and Molecular Imaging, Heart and Diabetes Center North Rhine-Westphalia, University Hospital Ruhr-University Bochum, Bad Oeynhausen, Germany
| | - Jennifer B Raftis
- BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Tanja K Rudolph
- Department of General and Interventional Cardiology/Angiology, Heart and Diabetes Center North Rhine-Westphalia, University Hospital Ruhr-University Bochum, Bad Oeynhausen, Germany
| | - Volker Rudolph
- Department of General and Interventional Cardiology/Angiology, Heart and Diabetes Center North Rhine-Westphalia, University Hospital Ruhr-University Bochum, Bad Oeynhausen, Germany
| | - Piotr Slomka
- Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, USA
| | | | - Adriana Tavares
- BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Evangelos Tzolos
- BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Nick Weir
- Edinburgh Imaging, Queen's Medical Research Institute, Edinburgh, United Kingdom
| | - Audrey C White
- BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Michelle C Williams
- BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom; Edinburgh Imaging, Queen's Medical Research Institute, Edinburgh, United Kingdom
| | - Reinhard Zabel
- Institute of Radiology, Nuclear Medicine and Molecular Imaging, Heart and Diabetes Center North Rhine-Westphalia, University Hospital Ruhr-University Bochum, Bad Oeynhausen, Germany
| | - Marc R Dweck
- BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Verena Hugenberg
- Institute of Radiology, Nuclear Medicine and Molecular Imaging, Heart and Diabetes Center North Rhine-Westphalia, University Hospital Ruhr-University Bochum, Bad Oeynhausen, Germany
| | - David E Newby
- BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
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Noh RM, Graveling AJ, Lang NN, White AC, Lee KK, Mills NL, Newby DE, Lang CC, Frier BM. Effect of hypoglycaemia on measures of myocardial blood flow and myocardial injury in adults with and without type 1 diabetes: A prospective, randomised, open-label, blinded endpoint, cross-over study. Endocrinol Diabetes Metab 2021; 4:e00258. [PMID: 34277982 PMCID: PMC8279606 DOI: 10.1002/edm2.258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 04/04/2021] [Accepted: 04/17/2021] [Indexed: 11/15/2022] Open
Abstract
AIMS This study examined the effect of experimentally-induced hypoglycaemia on measures of myocardial blood flow and myocardial injury in adults with, and without, type 1 diabetes. METHODS In a prospective, randomised, open-label, blinded, endpoint cross-over study, 17 young adults with type 1 diabetes with no cardiovascular risk factors, and 10 healthy non-diabetic volunteers, underwent hyperinsulinaemic-euglycaemic (blood glucose 4.5-5.5 mmol/L) and hypoglycaemic (2.2-2.5 mmol/L) clamps. Myocardial blood flow was assessed using transthoracic echocardiography Doppler coronary flow reserve (CFR) and myocardial injury using plasma high-sensitivity cardiac troponin I (hs-cTnI) concentration. RESULTS During hypoglycaemia, coronary flow reserve trended non-significantly lower in those with type 1 diabetes than in the non-diabetic participants (3.54 ± 0.47 vs. 3.89 ± 0.89). A generalised linear mixed-model analysis examined diabetes status and euglycaemia or hypoglycaemia as factors affecting CFR. No statistically significant difference in CFR was observed for diabetes status (p = .23) or between euglycaemia and hypoglycaemia (p = .31). No changes in hs-cTnI occurred during hypoglycaemia or in the recovery period (p = .86). CONCLUSIONS A small change in CFR was not statistically significant in this study, implying hypoglycaemia may require more than coronary vasomotor dysfunction to cause harm. Further larger studies are required to investigate this putative problem.
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Affiliation(s)
- Radzi M. Noh
- Department of DiabetesRoyal Infirmary of EdinburghEdinburghUK
| | | | - Ninian N. Lang
- Centre for Cardiovascular ScienceUniversity of EdinburghEdinburghUK
| | - Audrey C. White
- Centre for Cardiovascular ScienceUniversity of EdinburghEdinburghUK
| | - Kuan K. Lee
- Centre for Cardiovascular ScienceUniversity of EdinburghEdinburghUK
| | | | - David E. Newby
- Centre for Cardiovascular ScienceUniversity of EdinburghEdinburghUK
| | - Chim C. Lang
- Division of Molecular and Clinical MedicineUniversity of DundeeDundeeUK
| | - Brian M. Frier
- Department of DiabetesRoyal Infirmary of EdinburghEdinburghUK
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3
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Pawade TA, Doris MK, Bing R, White AC, Forsyth L, Evans E, Graham C, Williams MC, van Beek EJ, Fletcher A, Adamson PD, Andrews JP, Cartlidge TR, Jenkins WS, Syed M, Fujisawa T, Lucatelli C, Fraser W, Ralston SH, Boon N, Prendergast B, Newby DE, Dweck MR. Effect of Denosumab or Alendronic Acid on the Progression of Aortic Stenosis: A Double-Blind Randomized Controlled Trial. Circulation 2021; 143:2418-2427. [PMID: 33913339 PMCID: PMC8212878 DOI: 10.1161/circulationaha.121.053708] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 04/02/2021] [Indexed: 12/17/2022]
Abstract
BACKGROUND Valvular calcification is central to the pathogenesis and progression of aortic stenosis, with preclinical and observational studies suggesting that bone turnover and osteoblastic differentiation of valvular interstitial cells are important contributory mechanisms. We aimed to establish whether inhibition of these pathways with denosumab or alendronic acid could reduce disease progression in aortic stenosis. METHODS In a single-center, parallel group, double-blind randomized controlled trial, patients >50 years of age with calcific aortic stenosis (peak aortic jet velocity >2.5 m/s) were randomized 2:1:2:1 to denosumab (60 mg every 6 months), placebo injection, alendronic acid (70 mg once weekly), or placebo capsule. Participants underwent serial assessments with Doppler echocardiography, computed tomography aortic valve calcium scoring, and 18F-sodium fluoride positron emission tomography and computed tomography. The primary end point was the calculated 24-month change in aortic valve calcium score. RESULTS A total of 150 patients (mean age, 72±8 years; 21% women) with calcific aortic stenosis (peak aortic jet velocity, 3.36 m/s [2.93-3.82 m/s]; aortic valve calcium score, 1152 AU [655-2065 AU]) were randomized and received the allocated trial intervention: denosumab (n=49), alendronic acid (n=51), and placebo (injection n=25, capsule n=25; pooled for analysis). Serum C-terminal telopeptide, a measure of bone turnover, halved from baseline to 6 months with denosumab (0.23 [0.18-0.33 µg/L] to 0.11 µg/L [0.08-0.17 µg/L]) and alendronic acid (0.20 [0.14-0.28 µg/L] to 0.09 µg/L [0.08-0.13 µg/L]) but was unchanged with placebo (0.23 [0.17-0.30 µg/L] to 0.26 µg/L [0.16-0.31 µg/L]). There were no differences in 24-month change in aortic valve calcium score between denosumab and placebo (343 [198-804 AU] versus 354 AU [76-675 AU]; P=0.41) or alendronic acid and placebo (326 [138-813 AU] versus 354 AU [76-675 AU]; P=0.49). Similarly, there were no differences in change in peak aortic jet velocity or 18F-sodium fluoride aortic valve uptake. CONCLUSIONS Neither denosumab nor alendronic acid affected progression of aortic valve calcification in patients with calcific aortic stenosis. Alternative pathways and mechanisms need to be explored to identify disease-modifying therapies for the growing population of patients with this potentially fatal condition. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02132026.
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Affiliation(s)
- Tania A. Pawade
- British Heart Foundation Centre for Cardiovascular Science (T.A.P., M.K.D., R.B., A.C.W., M.C.W., P.D.A., J.P.M.A., T.R.G.C., W.S.A.J., M.S., T.F., N.B., D.E.N., M.R.D.), University of Edinburgh, United Kingdom
| | - Mhairi K. Doris
- British Heart Foundation Centre for Cardiovascular Science (T.A.P., M.K.D., R.B., A.C.W., M.C.W., P.D.A., J.P.M.A., T.R.G.C., W.S.A.J., M.S., T.F., N.B., D.E.N., M.R.D.), University of Edinburgh, United Kingdom
| | - Rong Bing
- British Heart Foundation Centre for Cardiovascular Science (T.A.P., M.K.D., R.B., A.C.W., M.C.W., P.D.A., J.P.M.A., T.R.G.C., W.S.A.J., M.S., T.F., N.B., D.E.N., M.R.D.), University of Edinburgh, United Kingdom
| | - Audrey C. White
- British Heart Foundation Centre for Cardiovascular Science (T.A.P., M.K.D., R.B., A.C.W., M.C.W., P.D.A., J.P.M.A., T.R.G.C., W.S.A.J., M.S., T.F., N.B., D.E.N., M.R.D.), University of Edinburgh, United Kingdom
| | - Laura Forsyth
- Edinburgh Clinical Trials Unit (L.F.), University of Edinburgh, United Kingdom
| | - Emily Evans
- Edinburgh Clinical Research Facility (E.E., C.G.), University of Edinburgh, United Kingdom
| | - Catriona Graham
- Edinburgh Clinical Research Facility (E.E., C.G.), University of Edinburgh, United Kingdom
| | - Michelle C. Williams
- British Heart Foundation Centre for Cardiovascular Science (T.A.P., M.K.D., R.B., A.C.W., M.C.W., P.D.A., J.P.M.A., T.R.G.C., W.S.A.J., M.S., T.F., N.B., D.E.N., M.R.D.), University of Edinburgh, United Kingdom
| | - Edwin J.R. van Beek
- Edinburgh Imaging (E.J.R.v.B., A.F., C.L.), University of Edinburgh, United Kingdom
| | - Alison Fletcher
- Edinburgh Imaging (E.J.R.v.B., A.F., C.L.), University of Edinburgh, United Kingdom
| | - Philip D. Adamson
- British Heart Foundation Centre for Cardiovascular Science (T.A.P., M.K.D., R.B., A.C.W., M.C.W., P.D.A., J.P.M.A., T.R.G.C., W.S.A.J., M.S., T.F., N.B., D.E.N., M.R.D.), University of Edinburgh, United Kingdom
- Christchurch Heart Institute, University of Otago, New Zealand (P.D.A.)
| | - Jack P.M. Andrews
- British Heart Foundation Centre for Cardiovascular Science (T.A.P., M.K.D., R.B., A.C.W., M.C.W., P.D.A., J.P.M.A., T.R.G.C., W.S.A.J., M.S., T.F., N.B., D.E.N., M.R.D.), University of Edinburgh, United Kingdom
| | - Timothy R.G. Cartlidge
- British Heart Foundation Centre for Cardiovascular Science (T.A.P., M.K.D., R.B., A.C.W., M.C.W., P.D.A., J.P.M.A., T.R.G.C., W.S.A.J., M.S., T.F., N.B., D.E.N., M.R.D.), University of Edinburgh, United Kingdom
| | - William S.A. Jenkins
- British Heart Foundation Centre for Cardiovascular Science (T.A.P., M.K.D., R.B., A.C.W., M.C.W., P.D.A., J.P.M.A., T.R.G.C., W.S.A.J., M.S., T.F., N.B., D.E.N., M.R.D.), University of Edinburgh, United Kingdom
| | - Maaz Syed
- British Heart Foundation Centre for Cardiovascular Science (T.A.P., M.K.D., R.B., A.C.W., M.C.W., P.D.A., J.P.M.A., T.R.G.C., W.S.A.J., M.S., T.F., N.B., D.E.N., M.R.D.), University of Edinburgh, United Kingdom
| | - Takeshi Fujisawa
- British Heart Foundation Centre for Cardiovascular Science (T.A.P., M.K.D., R.B., A.C.W., M.C.W., P.D.A., J.P.M.A., T.R.G.C., W.S.A.J., M.S., T.F., N.B., D.E.N., M.R.D.), University of Edinburgh, United Kingdom
| | - Christophe Lucatelli
- Edinburgh Imaging (E.J.R.v.B., A.F., C.L.), University of Edinburgh, United Kingdom
| | - William Fraser
- Norwich Medical School, University of East Anglia, United Kingdom (W.F.)
| | - Stuart H. Ralston
- Institute of Genetics and Molecular Medicine (S.H.R.), University of Edinburgh, United Kingdom
| | - Nicholas Boon
- British Heart Foundation Centre for Cardiovascular Science (T.A.P., M.K.D., R.B., A.C.W., M.C.W., P.D.A., J.P.M.A., T.R.G.C., W.S.A.J., M.S., T.F., N.B., D.E.N., M.R.D.), University of Edinburgh, United Kingdom
| | | | - David E. Newby
- British Heart Foundation Centre for Cardiovascular Science (T.A.P., M.K.D., R.B., A.C.W., M.C.W., P.D.A., J.P.M.A., T.R.G.C., W.S.A.J., M.S., T.F., N.B., D.E.N., M.R.D.), University of Edinburgh, United Kingdom
| | - Marc R. Dweck
- British Heart Foundation Centre for Cardiovascular Science (T.A.P., M.K.D., R.B., A.C.W., M.C.W., P.D.A., J.P.M.A., T.R.G.C., W.S.A.J., M.S., T.F., N.B., D.E.N., M.R.D.), University of Edinburgh, United Kingdom
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4
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Gu H, Bing R, Chin C, Fang L, White AC, Everett R, Spath N, Park E, Chambers JB, Newby DE, Chiribiri A, Dweck MR, Chowienczyk P. First-phase ejection fraction by cardiovascular magnetic resonance predicts outcomes in aortic stenosis. J Cardiovasc Magn Reson 2021; 23:73. [PMID: 34107986 PMCID: PMC8191208 DOI: 10.1186/s12968-021-00756-x] [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] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Accepted: 04/06/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND First-phase ejection fraction (EF1; the ejection fraction measured during active systole up to the time of maximal aortic flow) measured by transthoracic echocardiography (TTE) is a powerful predictor of outcomes in patients with aortic stenosis. We aimed to assess whether cardiovascular magnetic resonance (CMR) might provide more precise measurements of EF1 than TTE and to examine the correlation of CMR EF1 with measures of fibrosis. METHODS In 141 patients with at least mild aortic stenosis, we measured CMR EF1 from a short-axis 3D stack and compared its variability with TTE EF1, and its associations with myocardial fibrosis and clinical outcome (aortic valve replacement (AVR) or death). RESULTS Intra- and inter-observer variation of CMR EF1 (standard deviations of differences within and between observers of 2.3% and 2.5% units respectively) was approximately 50% that of TTE EF1. CMR EF1 was strongly predictive of AVR or death. On multivariable Cox proportional hazards analysis, the hazard ratio for CMR EF1 was 0.93 (95% confidence interval 0.89-0.97, p = 0.001) per % change in EF1 and, apart from aortic valve gradient, CMR EF1 was the only imaging or biochemical measure independently predictive of outcome. Indexed extracellular volume was associated with AVR or death, but not after adjusting for EF1. CONCLUSIONS EF1 is a simple robust marker of early left ventricular impairment that can be precisely measured by CMR and predicts outcome in aortic stenosis. Its measurement by CMR is more reproducible than that by TTE and may facilitate left ventricular structure-function analysis.
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Affiliation(s)
- Haotian Gu
- British Heart Foundation Centre of Research Excellence, King's College London, London, UK
| | - Rong Bing
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Heart Centre, Royal Infirmary of Edinburgh, Edinburgh, UK
| | - Calvin Chin
- Department of Cardiology, National Heart Centre, Singapore, Singapore
| | - Lingyun Fang
- Department of Ultrasound, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Audrey C White
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Russell Everett
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Heart Centre, Royal Infirmary of Edinburgh, Edinburgh, UK
| | - Nick Spath
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Eunsoo Park
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - John B Chambers
- Cardiothoracic Centre, Guy's and St Thomas's Hospitals, London, UK
| | - David E Newby
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Heart Centre, Royal Infirmary of Edinburgh, Edinburgh, UK
| | - Amedeo Chiribiri
- British Heart Foundation Centre of Research Excellence, King's College London, London, UK
| | - Marc R Dweck
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Heart Centre, Royal Infirmary of Edinburgh, Edinburgh, UK
| | - Phil Chowienczyk
- British Heart Foundation Centre of Research Excellence, King's College London, London, UK.
- Department of Clinical Pharmacology, St Thomas' Hospital, London, SE1 7EH, UK.
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5
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Zheng KH, Tsimikas S, Pawade T, Kroon J, Jenkins WSA, Doris MK, White AC, Timmers NKLM, Hjortnaes J, Rogers MA, Aikawa E, Arsenault BJ, Witztum JL, Newby DE, Koschinsky ML, Fayad ZA, Stroes ESG, Boekholdt SM, Dweck MR. Lipoprotein(a) and Oxidized Phospholipids Promote Valve Calcification in Patients With Aortic Stenosis. J Am Coll Cardiol 2020; 73:2150-2162. [PMID: 31047003 PMCID: PMC6494952 DOI: 10.1016/j.jacc.2019.01.070] [Citation(s) in RCA: 162] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 01/28/2019] [Accepted: 01/28/2019] [Indexed: 01/05/2023]
Abstract
Background Lipoprotein(a) [Lp(a)], a major carrier of oxidized phospholipids (OxPL), is associated with an increased incidence of aortic stenosis (AS). However, it remains unclear whether elevated Lp(a) and OxPL drive disease progression and are therefore targets for therapeutic intervention. Objectives This study investigated whether Lp(a) and OxPL on apolipoprotein B-100 (OxPL-apoB) levels are associated with disease activity, disease progression, and clinical events in AS patients, along with the mechanisms underlying any associations. Methods This study combined 2 prospective cohorts and measured Lp(a) and OxPL-apoB levels in patients with AS (Vmax >2.0 m/s), who underwent baseline 18F-sodium fluoride (18F-NaF) positron emission tomography (PET), repeat computed tomography calcium scoring, and repeat echocardiography. In vitro studies investigated the effects of Lp(a) and OxPL on valvular interstitial cells. Results Overall, 145 patients were studied (68% men; age 70.3 ± 9.9 years). On baseline positron emission tomography, patients in the top Lp(a) tertile had increased valve calcification activity compared with those in lower tertiles (n = 79; 18F-NaF tissue-to-background ratio of the most diseased segment: 2.16 vs. 1.97; p = 0.043). During follow-up, patients in the top Lp(a) tertile had increased progression of valvular computed tomography calcium score (n = 51; 309 AU/year [interquartile range: 142 to 483 AU/year] vs. 93 AU/year [interquartile range: 56 to 296 AU/year; p = 0.015), faster hemodynamic progression on echocardiography (n = 129; 0.23 ± 0.20 m/s/year vs. 0.14 ± 0.20 m/s/year] p = 0.019), and increased risk for aortic valve replacement and death (n = 145; hazard ratio: 1.87; 95% CI: 1.13 to 3.08; p = 0.014), compared with lower tertiles. Similar results were noted with OxPL-apoB. In vitro, Lp(a) induced osteogenic differentiation of valvular interstitial cells, mediated by OxPL and inhibited with the E06 monoclonal antibody against OxPL. Conclusions In patients with AS, Lp(a) and OxPL drive valve calcification and disease progression. These findings suggest lowering Lp(a) or inactivating OxPL may slow AS progression and provide a rationale for clinical trials to test this hypothesis.
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Affiliation(s)
- Kang H Zheng
- Department of Vascular Medicine, Academic Medical Center, Amsterdam UMC, Amsterdam, the Netherlands. https://twitter.com/Zheng_KH
| | - Sotirios Tsimikas
- Division of Cardiovascular Medicine, Sulpizio Cardiovascular Center, University of California, San Diego, La Jolla, California
| | - Tania Pawade
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Jeffrey Kroon
- Department of Vascular Medicine, Academic Medical Center, Amsterdam UMC, Amsterdam, the Netherlands
| | - William S A Jenkins
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Mhairi K Doris
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Audrey C White
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Nyanza K L M Timmers
- Department of Vascular Medicine, Academic Medical Center, Amsterdam UMC, Amsterdam, the Netherlands
| | - Jesper Hjortnaes
- Department of Cardiothoracic Surgery, UMC Utrecht, Utrecht, the Netherlands
| | - Maximillian A Rogers
- Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Elena Aikawa
- Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Benoit J Arsenault
- Centre de recherche de l'Institut Universitaire de cardiologie et de pneumologie de Québec-Université Laval, Québec City, Québec, Canada
| | - Joseph L Witztum
- Department of Medicine, Division of Endocrinology and Metabolism, University of California, San Diego, La Jolla, California
| | - David E Newby
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Marlys L Koschinsky
- Robarts Research Institute, University of Western Ontario, London, Ontario, Canada
| | - Zahi A Fayad
- Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Erik S G Stroes
- Department of Vascular Medicine, Academic Medical Center, Amsterdam UMC, Amsterdam, the Netherlands
| | - S Matthijs Boekholdt
- Department of Cardiology, Academic Medical Center, Amsterdam UMC, Amsterdam, the Netherlands
| | - Marc R Dweck
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom.
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6
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Spath NB, Gomez M, Everett RJ, Semple S, Chin CWL, White AC, Japp AG, Newby DE, Dweck MR. Global Longitudinal Strain Analysis Using Cardiac MRI in Aortic Stenosis: Comparison with Left Ventricular Remodeling, Myocardial Fibrosis, and 2-year Clinical Outcomes. Radiol Cardiothorac Imaging 2019; 1:e190027. [PMID: 33778518 DOI: 10.1148/ryct.2019190027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 05/15/2019] [Accepted: 05/23/2019] [Indexed: 12/20/2022]
Abstract
Purpose To use global longitudinal strain (GLS) as a marker of left ventricular decompensation in aortic stenosis and to investigate the relationship of GLS measured with cardiac MRI with markers of myocardial fibrosis, symptom development, remodeling, and clinical outcomes. Materials and Methods Patients with aortic stenosis and healthy control subjects were assessed. GLS was assessed by using cardiac MRI feature tracking, diffuse fibrosis by T1 mapping, and replacement fibrosis using late gadolinium enhancement. Follow-up was prospective for the primary endpoint of all-cause mortality. Results GLS was reduced in aortic stenosis (n = 159) compared with control subjects (n = 41) (-17.6% ± 3.1 [standard deviation] vs -18.9% ± 2.6, P = .02). GLS demonstrated weak associations with aortic stenosis severity (Vmax; r = 0.24, P = .0005) but showed moderate correlation with T1 mapping measures of myocardial fibrosis (eg, indexed extracellular volume [iECV]; r = 0.43, P < .0001). Moreover, GLS was reduced in patients with midwall fibrosis compared with control subjects (P < .001), although values were similar to those of patients with myocardial infarction (P = .25). In adjusted analyses, GLS was associated with total myocardial fibrosis burden (iECV) and ejection fraction (both P < .001). GLS offered poor discrimination between disease states, inability to distinguish between control subjects and patients (area under the curve [AUC], 0.60), presence or absence of fibrosis (AUC, 0.63), or symptomatic severity (left ventricular decompensation AUC, 0.64). At follow-up (median, 1466 days), 21 patients died. GLS did not independently predict clinical outcomes. Conclusion GLS correlates with established markers of myocardial fibrosis. However, widespread utility of single GLS measurements may be limited by overlap between disease states and its inability to predict clinical outcomes beyond current established markers.© RSNA, 2019Supplemental material is available for this article.
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Affiliation(s)
- Nicholas B Spath
- BHF/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 47 Little France Crescent, Edinburgh EH16 4SB, Scotland (N.B.S., R.J.E., S.S., A.C.W., A.G.J., D.E.N., M.R.D.); Hospital del Mar Medical Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain (M.G.); Department of Cardiovascular Science, National Heart Center, Singapore (C.W.L.C.); and Department of Cardiology, Royal Infirmary of Edinburgh, Edinburgh, Scotland (A.G.J., D.E.N., M.R.D.)
| | - Miquel Gomez
- BHF/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 47 Little France Crescent, Edinburgh EH16 4SB, Scotland (N.B.S., R.J.E., S.S., A.C.W., A.G.J., D.E.N., M.R.D.); Hospital del Mar Medical Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain (M.G.); Department of Cardiovascular Science, National Heart Center, Singapore (C.W.L.C.); and Department of Cardiology, Royal Infirmary of Edinburgh, Edinburgh, Scotland (A.G.J., D.E.N., M.R.D.)
| | - Russell J Everett
- BHF/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 47 Little France Crescent, Edinburgh EH16 4SB, Scotland (N.B.S., R.J.E., S.S., A.C.W., A.G.J., D.E.N., M.R.D.); Hospital del Mar Medical Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain (M.G.); Department of Cardiovascular Science, National Heart Center, Singapore (C.W.L.C.); and Department of Cardiology, Royal Infirmary of Edinburgh, Edinburgh, Scotland (A.G.J., D.E.N., M.R.D.)
| | - Scott Semple
- BHF/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 47 Little France Crescent, Edinburgh EH16 4SB, Scotland (N.B.S., R.J.E., S.S., A.C.W., A.G.J., D.E.N., M.R.D.); Hospital del Mar Medical Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain (M.G.); Department of Cardiovascular Science, National Heart Center, Singapore (C.W.L.C.); and Department of Cardiology, Royal Infirmary of Edinburgh, Edinburgh, Scotland (A.G.J., D.E.N., M.R.D.)
| | - Calvin W L Chin
- BHF/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 47 Little France Crescent, Edinburgh EH16 4SB, Scotland (N.B.S., R.J.E., S.S., A.C.W., A.G.J., D.E.N., M.R.D.); Hospital del Mar Medical Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain (M.G.); Department of Cardiovascular Science, National Heart Center, Singapore (C.W.L.C.); and Department of Cardiology, Royal Infirmary of Edinburgh, Edinburgh, Scotland (A.G.J., D.E.N., M.R.D.)
| | - Audrey C White
- BHF/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 47 Little France Crescent, Edinburgh EH16 4SB, Scotland (N.B.S., R.J.E., S.S., A.C.W., A.G.J., D.E.N., M.R.D.); Hospital del Mar Medical Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain (M.G.); Department of Cardiovascular Science, National Heart Center, Singapore (C.W.L.C.); and Department of Cardiology, Royal Infirmary of Edinburgh, Edinburgh, Scotland (A.G.J., D.E.N., M.R.D.)
| | - Alan G Japp
- BHF/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 47 Little France Crescent, Edinburgh EH16 4SB, Scotland (N.B.S., R.J.E., S.S., A.C.W., A.G.J., D.E.N., M.R.D.); Hospital del Mar Medical Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain (M.G.); Department of Cardiovascular Science, National Heart Center, Singapore (C.W.L.C.); and Department of Cardiology, Royal Infirmary of Edinburgh, Edinburgh, Scotland (A.G.J., D.E.N., M.R.D.)
| | - David E Newby
- BHF/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 47 Little France Crescent, Edinburgh EH16 4SB, Scotland (N.B.S., R.J.E., S.S., A.C.W., A.G.J., D.E.N., M.R.D.); Hospital del Mar Medical Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain (M.G.); Department of Cardiovascular Science, National Heart Center, Singapore (C.W.L.C.); and Department of Cardiology, Royal Infirmary of Edinburgh, Edinburgh, Scotland (A.G.J., D.E.N., M.R.D.)
| | - Marc R Dweck
- BHF/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 47 Little France Crescent, Edinburgh EH16 4SB, Scotland (N.B.S., R.J.E., S.S., A.C.W., A.G.J., D.E.N., M.R.D.); Hospital del Mar Medical Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain (M.G.); Department of Cardiovascular Science, National Heart Center, Singapore (C.W.L.C.); and Department of Cardiology, Royal Infirmary of Edinburgh, Edinburgh, Scotland (A.G.J., D.E.N., M.R.D.)
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7
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Everett RJ, Tastet L, Clavel MA, Chin CWL, Capoulade R, Vassiliou VS, Kwiecinski J, Gomez M, van Beek EJR, White AC, Prasad SK, Larose E, Tuck C, Semple S, Newby DE, Pibarot P, Dweck MR. Progression of Hypertrophy and Myocardial Fibrosis in Aortic Stenosis: A Multicenter Cardiac Magnetic Resonance Study. Circ Cardiovasc Imaging 2019; 11:e007451. [PMID: 29914867 PMCID: PMC6023592 DOI: 10.1161/circimaging.117.007451] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2017] [Accepted: 04/23/2018] [Indexed: 01/20/2023]
Abstract
Supplemental Digital Content is available in the text. Background: Aortic stenosis is accompanied by progressive left ventricular hypertrophy and fibrosis. We investigated the natural history of these processes in asymptomatic patients and their potential reversal post-aortic valve replacement (AVR). Methods: Asymptomatic and symptomatic patients with aortic stenosis underwent repeat echocardiography and magnetic resonance imaging. Changes in peak aortic-jet velocity, left ventricular mass index, diffuse fibrosis (indexed extracellular volume), and replacement fibrosis (late gadolinium enhancement [LGE]) were quantified. Results: In 61 asymptomatic patients (43% mild, 34% moderate, and 23% severe aortic stenosis), significant increases in peak aortic-jet velocity, left ventricular mass index, indexed extracellular volume, and LGE mass were observed after 2.1±0.7 years, with the most rapid progression observed in patients with most severe stenosis. Patients with baseline midwall LGE (n=16 [26%]; LGE mass, 2.5 g [0.8–4.8 g]) demonstrated particularly rapid increases in scar burden (78% [50%–158%] increase in LGE mass per year). In 38 symptomatic patients (age, 66±8 years; 76% men) who underwent AVR, there was a 19% (11%–25%) reduction in left ventricular mass index (P<0.0001) and an 11% (4%–16%) reduction in indexed extracellular volume (P=0.003) 0.9±0.3 years after surgery. By contrast midwall LGE (n=10 [26%]; mass, 3.3 g [2.6–8.0 g]) did not change post-AVR (n=10; 3.5 g [2.1–8.0 g]; P=0.23), with no evidence of regression even out to 2 years. Conclusions: In patients with aortic stenosis, cellular hypertrophy and diffuse fibrosis progress in a rapid and balanced manner but are reversible after AVR. Once established, midwall LGE also accumulates rapidly but is irreversible post valve replacement. Given its adverse long-term prognosis, prompt AVR when midwall LGE is first identified may improve clinical outcomes. Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifiers: NCT01755936 and NCT01679431.
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Affiliation(s)
- Russell J Everett
- British Heart Foundation Centre for Cardiovascular Science (R.J.E., J.K., M.G., E.J.R.v.B., C.W., S.S., D.E.N., M.R.D.)
| | - Lionel Tastet
- University of Edinburgh, United Kingdom. Department of Medicine, Quebec Heart and Lung Institute, Canada (L.T., M.-A.C., R.C., E.L., P.P.)
| | - Marie-Annick Clavel
- University of Edinburgh, United Kingdom. Department of Medicine, Quebec Heart and Lung Institute, Canada (L.T., M.-A.C., R.C., E.L., P.P.)
| | - Calvin W L Chin
- Department of Cardiovascular Science, National Heart Center Singapore (C.W.L.C.)
| | - Romain Capoulade
- University of Edinburgh, United Kingdom. Department of Medicine, Quebec Heart and Lung Institute, Canada (L.T., M.-A.C., R.C., E.L., P.P.)
| | - Vassilios S Vassiliou
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom (V.S.V., S.K.P.).,Norwich Medical School, Norfolk and Norwich University Hospital, United Kingdom (V.S.V.)
| | - Jacek Kwiecinski
- British Heart Foundation Centre for Cardiovascular Science (R.J.E., J.K., M.G., E.J.R.v.B., C.W., S.S., D.E.N., M.R.D.).,First Department of Cardiology, Poznan University of Medical Sciences, Poland (J.K.)
| | - Miquel Gomez
- British Heart Foundation Centre for Cardiovascular Science (R.J.E., J.K., M.G., E.J.R.v.B., C.W., S.S., D.E.N., M.R.D.).,Hospital del Mar Medical Research Institute, Universitat Pompeu Fabra, Barcelona, Spain (M.G.)
| | - Edwin J R van Beek
- British Heart Foundation Centre for Cardiovascular Science (R.J.E., J.K., M.G., E.J.R.v.B., C.W., S.S., D.E.N., M.R.D.).,Edinburgh Imaging Queen's Medical Research Institute Facility (E.J.R.v.B., S.S.)
| | | | - Sanjay K Prasad
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, United Kingdom (V.S.V., S.K.P.)
| | - Eric Larose
- University of Edinburgh, United Kingdom. Department of Medicine, Quebec Heart and Lung Institute, Canada (L.T., M.-A.C., R.C., E.L., P.P.)
| | - Christopher Tuck
- British Heart Foundation Centre for Cardiovascular Science (R.J.E., J.K., M.G., E.J.R.v.B., C.W., S.S., D.E.N., M.R.D.).,Edinburgh Clinical Trials Unit, Usher Institute of Population Health Sciences and Informatics (C.T.)
| | - Scott Semple
- British Heart Foundation Centre for Cardiovascular Science (R.J.E., J.K., M.G., E.J.R.v.B., C.W., S.S., D.E.N., M.R.D.).,Edinburgh Imaging Queen's Medical Research Institute Facility (E.J.R.v.B., S.S.)
| | - David E Newby
- British Heart Foundation Centre for Cardiovascular Science (R.J.E., J.K., M.G., E.J.R.v.B., C.W., S.S., D.E.N., M.R.D.)
| | - Philippe Pibarot
- University of Edinburgh, United Kingdom. Department of Medicine, Quebec Heart and Lung Institute, Canada (L.T., M.-A.C., R.C., E.L., P.P.)
| | - Marc R Dweck
- British Heart Foundation Centre for Cardiovascular Science (R.J.E., J.K., M.G., E.J.R.v.B., C.W., S.S., D.E.N., M.R.D.)
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8
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Cartlidge TRG, Doris MK, Sellers SL, Pawade TA, White AC, Pessotto R, Kwiecinski J, Fletcher A, Alcaide C, Lucatelli C, Densem C, Rudd JHF, van Beek EJR, Tavares A, Virmani R, Berman D, Leipsic JA, Newby DE, Dweck MR. Detection and Prediction of Bioprosthetic Aortic Valve Degeneration. J Am Coll Cardiol 2019; 73:1107-1119. [PMID: 30871693 PMCID: PMC6424589 DOI: 10.1016/j.jacc.2018.12.056] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 11/21/2018] [Accepted: 12/02/2018] [Indexed: 11/22/2022]
Abstract
BACKGROUND Bioprosthetic aortic valve degeneration is increasingly common, often unheralded, and can have catastrophic consequences. OBJECTIVES The authors sought to assess whether 18F-fluoride positron emission tomography (PET)-computed tomography (CT) can detect bioprosthetic aortic valve degeneration and predict valve dysfunction. METHODS Explanted degenerate bioprosthetic valves were examined ex vivo. Patients with bioprosthetic aortic valves were recruited into 2 cohorts with and without prosthetic valve dysfunction and underwent in vivo contrast-enhanced CT angiography, 18F-fluoride PET, and serial echocardiography during 2 years of follow-up. RESULTS All ex vivo, degenerate bioprosthetic valves displayed 18F-fluoride PET uptake that colocalized with tissue degeneration on histology. In 71 patients without known bioprosthesis dysfunction, 14 had abnormal leaflet pathology on CT, and 24 demonstrated 18F-fluoride PET uptake (target-to-background ratio 1.55 [interquartile range (IQR): 1.44 to 1.88]). Patients with increased 18F-fluoride uptake exhibited more rapid deterioration in valve function compared with those without (annualized change in peak transvalvular velocity 0.30 [IQR: 0.13 to 0.61] vs. 0.01 [IQR: -0.05 to 0.16] ms-1/year; p < 0.001). Indeed 18F-fluoride uptake correlated with deterioration in all the conventional echocardiographic measures of valve function assessed (e.g., change in peak velocity, r = 0.72; p < 0.001). Each of the 10 patients who developed new overt bioprosthesis dysfunction during follow-up had evidence of 18F-fluoride uptake at baseline (target-to-background ratio 1.89 [IQR: 1.46 to 2.59]). On multivariable analysis, 18F-fluoride uptake was the only independent predictor of future bioprosthetic dysfunction. CONCLUSIONS 18F-fluoride PET-CT identifies subclinical bioprosthetic valve degeneration, providing powerful prediction of subsequent valvular dysfunction and highlighting patients at risk of valve failure. This technique holds major promise in the diagnosis of valvular degeneration and the surveillance of patients with bioprosthetic valves. (18F-Fluoride Assessment of Aortic Bioprosthesis Durability and Outcome [18F-FAABULOUS]; NCT02304276).
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Affiliation(s)
- Timothy R G Cartlidge
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Mhairi K Doris
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Stephanie L Sellers
- Edinburgh Imaging Facility, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Tania A Pawade
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Audrey C White
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Renzo Pessotto
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Jacek Kwiecinski
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Alison Fletcher
- Department of Radiology, St. Paul's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Carlos Alcaide
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Christophe Lucatelli
- Department of Radiology, St. Paul's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Cameron Densem
- Department of Cardiology, Papworth Hospital NHS Foundation Trust, Cambridge, United Kingdom
| | - James H F Rudd
- Division of Cardiovascular Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Edwin J R van Beek
- Department of Radiology, St. Paul's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Adriana Tavares
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | | | - Daniel Berman
- Cedars-Sinai Heart Institute, Los Angeles, California
| | - Jonathon A Leipsic
- Edinburgh Imaging Facility, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - David E Newby
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Marc R Dweck
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom.
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Jenkins WS, Pawade TA, Cartlidge T, Shah ASV, Williams M, White AC, Van Beek EJ, Newby DE, Dweck MR. P6052Computed tomography aortic valve calcium scoring is highly reproducible and predicts disease progression in aortic stenosis. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy566.p6052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- W S Jenkins
- University of Edinburgh, Centre for Cardiovascular Science, Edinburgh, United Kingdom
| | - T A Pawade
- University of Edinburgh, Centre for Cardiovascular Science, Edinburgh, United Kingdom
| | - T Cartlidge
- University of Edinburgh, Centre for Cardiovascular Science, Edinburgh, United Kingdom
| | - A S V Shah
- University of Edinburgh, Centre for Cardiovascular Science, Edinburgh, United Kingdom
| | - M Williams
- University of Edinburgh, Centre for Cardiovascular Science, Edinburgh, United Kingdom
| | - A C White
- University of Edinburgh, Centre for Cardiovascular Science, Edinburgh, United Kingdom
| | - E J Van Beek
- University of Edinburgh, Centre for Cardiovascular Science, Edinburgh, United Kingdom
| | - D E Newby
- University of Edinburgh, Centre for Cardiovascular Science, Edinburgh, United Kingdom
| | - M R Dweck
- University of Edinburgh, Centre for Cardiovascular Science, Edinburgh, United Kingdom
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10
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Kwiecinski J, Chin CWL, Everett RJ, White AC, Semple S, Yeung E, Jenkins WJ, Shah ASV, Koo M, Mirsadraee S, Lang CC, Mills N, Prasad SK, Jansen MA, Japp AG, Newby DE, Dweck MR. Adverse prognosis associated with asymmetric myocardial thickening in aortic stenosis. Eur Heart J Cardiovasc Imaging 2018; 19:347-356. [PMID: 28379401 PMCID: PMC5837366 DOI: 10.1093/ehjci/jex052] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 02/27/2017] [Accepted: 02/28/2017] [Indexed: 11/14/2022] Open
Abstract
Aims Asymmetric wall thickening has been described in patients with aortic stenosis. However, it remains poorly characterized and its prognostic implications are unclear. We hypothesized this pattern of adaptation is associated with advanced remodelling, left ventricular decompenzation, and a poor prognosis. Methods and results In a prospective observational cohort study, 166 patients with aortic stenosis (age 69, 69% males, mean aortic valve area 1.0 ± 0.4 cm2) and 37 age and sex-matched healthy volunteers underwent phenotypic characterization with comprehensive clinical, imaging, and biomarker evaluation. Asymmetric wall thickening on both echocardiography and cardiovascular magnetic resonance was defined as regional wall thickening ≥ 13 mm and > 1.5-fold the thickness of the opposing myocardial segment. Although no control subject had asymmetric wall thickening, it was observed in 26% (n = 43) of patients with aortic stenosis using magnetic resonance and 17% (n = 29) using echocardiography. Despite similar demographics, co-morbidities, valve narrowing, myocardial hypertrophy, and fibrosis, patients with asymmetric wall thickening had increased cardiac troponin I and brain natriuretic peptide concentrations (both P < 0.001). Over 28 [22, 33] months of follow-up, asymmetric wall thickening was an independent predictor of aortic valve replacement (AVR) or death whether detected by magnetic resonance [hazard ratio (HR) = 2.15; 95% confidence interval (CI) 1.29-3.59; P = 0.003] or echocardiography (HR = 1.79; 95% CI 1.08-3.69; P = 0.021). Conclusion Asymmetric wall thickening is common in aortic stenosis and is associated with increased myocardial injury, left ventricular decompenzation, and adverse events. Its presence may help identify patients likely to proceed quickly towards AVR. Clinical Trial Registration https://clinicaltrials.gov/show/NCT01755936: NCT01755936.
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Affiliation(s)
- Jacek Kwiecinski
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
- First Department of Cardiology, Poznan University of Medical Sciences, 1/2 Dluga, 61-848 Poznan, Poland
| | - Calvin W L Chin
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
- Department of Cardiovascular Science, National Heart Center Singapore
| | - Russell J Everett
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Audrey C White
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Scott Semple
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
- Clinical Research Imaging Centre, University of Edinburgh, UK
| | - Emily Yeung
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - William J Jenkins
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Anoop S V Shah
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Maria Koo
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Saeed Mirsadraee
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Chim C Lang
- Division of Cardiovascular and Diabetes Medicine, Ninewells Hospital and Medical School, UK
| | - Nicholas Mills
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | | | - Maurits A Jansen
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Alan G Japp
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - David E Newby
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Marc R Dweck
- BHF/Centre for Cardiovascular Science, University of Edinburgh, 49 Little France Crescent, Edinburgh EH16 4SB, UK
- Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York
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11
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Chin CWL, Everett RJ, Kwiecinski J, Vesey AT, Yeung E, Esson G, Jenkins W, Koo M, Mirsadraee S, White AC, Japp AG, Prasad SK, Semple S, Newby DE, Dweck MR. Myocardial Fibrosis and Cardiac Decompensation in Aortic Stenosis. JACC Cardiovasc Imaging 2016; 10:1320-1333. [PMID: 28017384 PMCID: PMC5683736 DOI: 10.1016/j.jcmg.2016.10.007] [Citation(s) in RCA: 248] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 10/04/2016] [Accepted: 10/05/2016] [Indexed: 11/24/2022]
Abstract
OBJECTIVES Cardiac magnetic resonance (CMR) was used to investigate the extracellular compartment and myocardial fibrosis in patients with aortic stenosis, as well as their association with other measures of left ventricular decompensation and mortality. BACKGROUND Progressive myocardial fibrosis drives the transition from hypertrophy to heart failure in aortic stenosis. Diffuse fibrosis is associated with extracellular volume expansion that is detectable by T1 mapping, whereas late gadolinium enhancement (LGE) detects replacement fibrosis. METHODS In a prospective observational cohort study, 203 subjects (166 with aortic stenosis [69 years; 69% male]; 37 healthy volunteers [68 years; 65% male]) underwent comprehensive phenotypic characterization with clinical imaging and biomarker evaluation. On CMR, we quantified the total extracellular volume of the myocardium indexed to body surface area (iECV). The iECV upper limit of normal from the control group (22.5 ml/m2) was used to define extracellular compartment expansion. Areas of replacement mid-wall LGE were also identified. All-cause mortality was determined during 2.9 ± 0.8 years of follow up. RESULTS iECV demonstrated a good correlation with diffuse histological fibrosis on myocardial biopsies (r = 0.87; p < 0.001; n = 11) and was increased in patients with aortic stenosis (23.6 ± 7.2 ml/m2 vs. 16.1 ± 3.2 ml/m2 in control subjects; p < 0.001). iECV was used together with LGE to categorize patients with normal myocardium (iECV <22.5 ml/m2; 51% of patients), extracellular expansion (iECV ≥22.5 ml/m2; 22%), and replacement fibrosis (presence of mid-wall LGE, 27%). There was evidence of increasing hypertrophy, myocardial injury, diastolic dysfunction, and longitudinal systolic dysfunction consistent with progressive left ventricular decompensation (all p < 0.05) across these groups. Moreover, this categorization was of prognostic value with stepwise increases in unadjusted all-cause mortality (8 deaths/1,000 patient-years vs. 36 deaths/1,000 patient-years vs. 71 deaths/1,000 patient-years, respectively; p = 0.009). CONCLUSIONS CMR detects ventricular decompensation in aortic stenosis through the identification of myocardial extracellular expansion and replacement fibrosis. This holds major promise in tracking myocardial health in valve disease and for optimizing the timing of valve replacement. (The Role of Myocardial Fibrosis in Patients With Aortic Stenosis; NCT01755936).
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Affiliation(s)
- Calvin W L Chin
- BHF/Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom; Department of Cardiovascular Science, National Heart Center, Singapore
| | - Russell J Everett
- BHF/Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Jacek Kwiecinski
- BHF/Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom; First Department of Cardiology, Poznan University of Medical Sciences, Poznan, Poland
| | - Alex T Vesey
- BHF/Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Emily Yeung
- BHF/Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Gavin Esson
- BHF/Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - William Jenkins
- BHF/Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Maria Koo
- BHF/Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Saeed Mirsadraee
- BHF/Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Audrey C White
- BHF/Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Alan G Japp
- BHF/Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | | | - Scott Semple
- Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, United Kingdom
| | - David E Newby
- BHF/Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Marc R Dweck
- BHF/Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom.
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12
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Del Brutto OH, Nash TE, White AC, Rajshekhar V, Wilkins PP, Singh G, Vasquez CM, Salgado P, Gilman RH, Garcia HH. Revised set of diagnostic criteria for neurocysticercosis (in reply to Garg and Malhotra). J Neurol Sci 2016; 373:350-351. [PMID: 28011076 DOI: 10.1016/j.jns.2016.12.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 12/12/2016] [Indexed: 11/25/2022]
Affiliation(s)
- O H Del Brutto
- School of Medicine, Universidad Espíritu Santo - Ecuador, Guayaquil, Ecuador.
| | - T E Nash
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institute of Health, Bethesda, MD, United States
| | - A C White
- Infectious Disease Division, Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - V Rajshekhar
- Department of Neurological Sciences, Christian Medical College Hospital, Vellore, India
| | - P P Wilkins
- Parasitology Services, Marathon, Fl, United States
| | - G Singh
- Department of Neurology, Dayanand Medical College, Ludhiana, India
| | - C M Vasquez
- Department of Neurosurgery, Instituto Nacional de Ciencias Neurológicas, Lima, Peru
| | - P Salgado
- Neuroimaging Unit, National Institute of Neurology and Neurosurgery Manuel Velasco Suarez, Mexico City, Mexico
| | - R H Gilman
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - H H Garcia
- Center for Global Health, Tumbes and the Department of Microbiology, School of Sciences, Universidad Peruana Cayetano Heredia, Peru; Cysticercosis Unit, Instituto Nacional de Ciencias Neurológicas, Lima, Peru
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13
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Del Brutto OH, Nash TE, White AC, Rajshekhar V, Wilkins PP, Singh G, Vasquez CM, Salgado P, Gilman RH, Garcia HH. Revised diagnostic criteria for neurocysticercosis. J Neurol Sci 2016; 372:202-210. [PMID: 28017213 DOI: 10.1016/j.jns.2016.11.045] [Citation(s) in RCA: 169] [Impact Index Per Article: 21.1] [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: 06/22/2016] [Revised: 10/29/2016] [Accepted: 11/20/2016] [Indexed: 10/20/2022]
Abstract
BACKGROUND A unified set of criteria for neurocysticercosis (NCC) has helped to standardize its diagnosis in different settings. METHODS Cysticercosis experts were convened to update current diagnostic criteria for NCC according to two principles: neuroimaging studies are essential for diagnosis, and all other information provides indirect evidence favoring the diagnosis. Recent diagnostic advances were incorporated to this revised set. RESULTS This revised set is structured in absolute, neuroimaging and clinical/exposure criteria. Absolute criteria include: histological confirmation of parasites, evidence of subretinal cysts, and demonstration of the scolex within a cyst. Neuroimaging criteria are categorized as major (cystic lesions without scolex, enhancing lesions, multilobulated cysts, and calcifications), confirmative (resolution of cysts after cysticidal drug therapy, spontaneous resolution of single enhancing lesions, and migrating ventricular cysts on sequential neuroimaging studies) and minor (hydrocephalus and leptomeningeal enhancement). Clinical/exposure criteria include: detection of anticysticercal antibodies or cysticercal antigens by well-standardized tests, systemic cysticercosis, evidence of a household Taenia carrier, suggestive clinical manifestations, and residency in endemic areas. Besides patients having absolute criteria, definitive diagnosis can be made in those having two major neuroimaging criteria (or one major plus one confirmative criteria) plus exposure. For patients presenting with one major and one minor neuroimaging criteria plus exposure, definitive diagnosis of NCC requires the exclusion of confounding pathologies. Probable diagnosis is reserved for individuals presenting with one neuroimaging criteria plus strong evidence of exposure. CONCLUSIONS This revised set of diagnostic criteria provides simpler definitions and may facilitate its more uniform and widespread applicability in different scenarios.
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Affiliation(s)
- O H Del Brutto
- School of Medicine, Universidad Espíritu Santo - Ecuador, Guayaquil, Ecuador
| | - T E Nash
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institute of Health, Bethesda, MD, United States
| | - A C White
- Infectious Disease Division, Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - V Rajshekhar
- Department of Neurological Sciences, Christian Medical College Hospital, Vellore, India
| | - P P Wilkins
- Parasitology Services, Marathon, FL, United States
| | - G Singh
- Department of Neurology, Dayanand Medical College, Ludhiana, India
| | - C M Vasquez
- Department of Neurosurgery, Instituto Nacional de Ciencias Neurológicas, Lima, Peru
| | - P Salgado
- Neuroimaging Unit, National Institute of Neurology and Neurosurgery Manuel Velasco Suarez, Mexico City, Mexico
| | - R H Gilman
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - H H Garcia
- Center for Global Health, Tumbes, Peru; Department of Microbiology, School of Sciences, Universidad Peruana Cayetano Heredia, Peru; Cysticercosis Unit, Instituto Nacional de Ciencias Neurológicas, Lima, Peru.
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14
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Smith NH, Musher DM, Huang DB, Rodriguez PS, Dowell ME, Ace W, White AC. Response of HIV-Infected Patients with Asymptomatic Syphilis to Intensive Intramuscular Therapy with Ceftriaxone or Procaine Penicillin. Int J STD AIDS 2016; 15:328-32. [PMID: 15117503 DOI: 10.1177/095646240401500511] [Citation(s) in RCA: 37] [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] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The objective of this prospective pilot study was to evaluate the response of HIV-infected patients with asymptomatic syphilis to one of two intensive antibiotic treatment regimens. Thirty-one HIV-infected patients with serum rapid plasma reagin titre ≥1:4 and no clinical findings of syphilis were randomized to receive daily intramuscular injections of ceftriaxone or procaine penicillin (plus oral probenecid) for 15 days; 24 returned for follow-up study. Seven of 10 (70%) procaine penicillin-treated patients and 10 of 14 (71%) ceftriaxone-treated patients had a ≥4-fold decline in RPR ( P=0.94); two penicillin-treated and one ceftriaxone-treated patient relapsed. Two patients failed ceftriaxone therapy. Three penicillin-treated, and two ceftriaxone-treated patients were serofast. Serological responses were similar in those patients with and without asymptomatic neurosyphilis. There was no difference in the serologic response to daily treatment with ceftriaxone vs that with procaine penicillin plus probenecid; both treatments were associated with comparatively high rates of serological non-response and relapse.
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Affiliation(s)
- N H Smith
- Infectious Disease Section, Department of Medicine, Baylor College of Medicine, One Baylor Plaza, 561E, Houston, Texas 77030, USA
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15
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Villanueva-Meyer PG, Garcia-Jasso CA, Springer CA, Lane JK, Su BS, Hidalgo IS, Goodrich MR, Deichsel EL, White AC, Cabada MM. Advice on malaria and yellow fever prevention provided at travel agencies in Cuzco, Peru. J Travel Med 2015; 22:26-30. [PMID: 25156197 DOI: 10.1111/jtm.12149] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [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] [Received: 03/12/2014] [Revised: 05/30/2014] [Accepted: 07/01/2014] [Indexed: 11/29/2022]
Abstract
BACKGROUND Travelers receive medical advice from a variety of sources, including travel agencies. The aim of this study is to describe the quality of pre-travel advice provided by travel agencies in Cuzco to travelers interested in visiting malaria and yellow fever endemic areas. METHODS Trained medical students posed as tourists and visited travel agencies in Cuzco requesting travel advice for a trip to the southern Amazon of Peru, recording advice regarding risk and prevention of malaria and yellow fever. RESULTS A total of 163 registered travel agencies were included in the study. The mean proposed tour duration was 6.8 days (±1.4 days) with a median time to departure of 3 days and a median tour cost of 805 US dollars (USD) [interquartile range (IQR) 580-1,095]. Overall, 45% employees failed to mention the risk for any illness. Eighteen percent of the employees acknowledged risk of malaria and 53% risk of yellow fever. However, 36% denied malaria risk and 2% denied risk of yellow fever in the region. The price of tours from travel agencies that did not mention any health risk was significantly lower [1,009.6 ± 500.5 vs 783.9 ± 402 USD, t (152) = 3, p < 0.01] compared with the price from agencies that did mention health risks. Almost all who acknowledged malaria (97%) and/or yellow fever (100%) were able to provide at least one recommendation for prevention. However, advice was not always accurate or spontaneously volunteered. Only 7% of the employees provided both correct scheduling and location information for administration of the yellow fever vaccine. CONCLUSIONS The majority of registered travel agencies in Cuzco did not provide sufficient and accurate information regarding risk and prevention of malaria and yellow fever to travelers inquiring about trips to the southern Amazon of Peru.
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Shah ASV, Chin CWL, Vassiliou V, Cowell SJ, Doris M, Kwok TC, Semple S, Zamvar V, White AC, McKillop G, Boon NA, Prasad SK, Mills NL, Newby DE, Dweck MR. Left ventricular hypertrophy with strain and aortic stenosis. Circulation 2014; 130:1607-16. [PMID: 25170097 DOI: 10.1161/circulationaha.114.011085] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND ECG left ventricular hypertrophy with strain is associated with an adverse prognosis in aortic stenosis. We investigated the mechanisms and outcomes associated with ECG strain. METHODS AND RESULTS One hundred and two patients (age, 70 years [range, 63-75 years]; male, 66%; aortic valve area, 0.9 cm(2) [range, 0.7-1.2 cm(2)]) underwent ECG, echocardiography, and cardiovascular magnetic resonance. They made up the mechanism cohort. Myocardial fibrosis was determined with late gadolinium enhancement (replacement fibrosis) and T1 mapping (diffuse fibrosis). The relationship between ECG strain and cardiovascular magnetic resonance was then assessed in an external validation cohort (n=64). The outcome cohort was made up of 140 patients from the Scottish Aortic Stenosis and Lipid Lowering Trial Impact on Regression (SALTIRE) study and was followed up for 10.6 years (1254 patient-years). Compared with those without left ventricular hypertrophy (n=51) and left ventricular hypertrophy without ECG strain (n=30), patients with ECG strain (n=21) had more severe aortic stenosis, increased left ventricular mass index, more myocardial injury (high-sensitivity plasma cardiac troponin I concentration, 4.3 ng/L [interquartile range, 2.5-7.3 ng/L] versus 7.3 ng/L [interquartile range, 3.2-20.8 ng/L] versus 18.6 ng/L [interquartile range, 9.0-45.2 ng/L], respectively; P<0.001) and increased diffuse fibrosis (extracellular volume fraction, 27.4±2.2% versus 27.2±2.9% versus 30.9±1.9%, respectively; P<0.001). All patients with ECG strain had midwall late gadolinium enhancement (positive and negative predictive values of 100% and 86%, respectively). Indeed, late gadolinium enhancement was independently associated with ECG strain (odds ratio, 1.73; 95% confidence interval, 1.08-2.77; P=0.02), a finding confirmed in the validation cohort. In the outcome cohort, ECG strain was an independent predictor of aortic valve replacement or cardiovascular death (hazard ratio, 2.67; 95% confidence interval, 1.35-5.27; P<0.01). CONCLUSION ECG strain is a specific marker of midwall myocardial fibrosis and predicts adverse clinical outcomes in aortic stenosis.
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Affiliation(s)
- Anoop S V Shah
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.)
| | - Calvin W L Chin
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.).
| | - Vassilis Vassiliou
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.)
| | - S Joanna Cowell
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.)
| | - Mhairi Doris
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.)
| | - T'ng Choong Kwok
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.)
| | - Scott Semple
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.)
| | - Vipin Zamvar
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.)
| | - Audrey C White
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.)
| | - Graham McKillop
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.)
| | - Nicholas A Boon
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.)
| | - Sanjay K Prasad
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.)
| | - Nicholas L Mills
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.)
| | - David E Newby
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.)
| | - Marc R Dweck
- From the British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK (A.S.V.S., C.W.L.C., M.D., T.C.K., S.S., A.C.W., N.A.B., N.L.M., D.E.N., M.R.D.); Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore (C.W.L.C.); Royal Brompton Hospital, London, UK (V.V., S.K.P.); National Heart and Lung Institute, Imperial College, London, UK (V.V., S.K.P.); NHS Lothian, Edinburgh, UK (S.J.C., A.C.W., G.M., N.A.B., N.L.M., D.E.N., M.R.D.); Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, UK (S.S., D.E.N.); and Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK (V.Z.)
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17
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White AC, Khuu JK, Dang CY, Hu J, Tran KV, Liu A, Gomez S, Zhang Z, Yi R, Scumpia P, Grigorian M, Lowry WE. Stem cell quiescence acts as a tumour suppressor in squamous tumours. Nat Cell Biol 2013; 16:99-107. [PMID: 24335650 PMCID: PMC3874399 DOI: 10.1038/ncb2889] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Accepted: 10/31/2013] [Indexed: 12/23/2022]
Abstract
In some organs, adult stem cells are uniquely poised to serve as cancer cells of origin. It is unclear, however, whether tumorigenesis is influenced by the activation state of the adult stem cell. Hair follicle stem cells (HFSCs) act as cancer cells of origin for cutaneous squamous cell carcinoma (SCC) and undergo defined cycles of quiescence and activation. The data presented here show that HFSCs are unable to initiate tumors during the quiescent phase of the hair cycle, indicating that the mechanisms that keep HFSCs dormant are dominant to the gain of oncogenes (Ras) or the loss of tumor suppressors (p53). Furthermore, Pten activity is necessary for quiescence based tumor suppression, as its deletion alleviates tumor suppression without affecting proliferation. These data demonstrate that stem cell quiescence is a form of tumor suppression in HFSCs, and that Pten plays a role in maintaining quiescence in the presence of tumorigenic stimuli.
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Affiliation(s)
- A C White
- 1] Department of Molecular Cell and Developmental Biology, UCLA, California 90095, USA [2] Eli and Edythe Broad Center for Regenerative Medicine, UCLA, California 90095, USA
| | - J K Khuu
- 1] Department of Molecular Cell and Developmental Biology, UCLA, California 90095, USA [2] Eli and Edythe Broad Center for Regenerative Medicine, UCLA, California 90095, USA
| | - C Y Dang
- 1] Department of Molecular Cell and Developmental Biology, UCLA, California 90095, USA [2] Eli and Edythe Broad Center for Regenerative Medicine, UCLA, California 90095, USA
| | - J Hu
- 1] Department of Molecular Cell and Developmental Biology, UCLA, California 90095, USA [2] Eli and Edythe Broad Center for Regenerative Medicine, UCLA, California 90095, USA
| | - K V Tran
- 1] Department of Molecular Cell and Developmental Biology, UCLA, California 90095, USA [2] Eli and Edythe Broad Center for Regenerative Medicine, UCLA, California 90095, USA
| | - A Liu
- 1] Department of Molecular Cell and Developmental Biology, UCLA, California 90095, USA [2] Eli and Edythe Broad Center for Regenerative Medicine, UCLA, California 90095, USA
| | - S Gomez
- 1] Department of Molecular Cell and Developmental Biology, UCLA, California 90095, USA [2] Eli and Edythe Broad Center for Regenerative Medicine, UCLA, California 90095, USA
| | - Z Zhang
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado 80309, USA
| | - R Yi
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado 80309, USA
| | - P Scumpia
- Department of Medicine, Division of Dermatology, David Geffen School of Medicine, UCLA, California 90095, USA
| | - M Grigorian
- 1] Department of Molecular Cell and Developmental Biology, UCLA, California 90095, USA [2] Eli and Edythe Broad Center for Regenerative Medicine, UCLA, California 90095, USA
| | - W E Lowry
- 1] Department of Molecular Cell and Developmental Biology, UCLA, California 90095, USA [2] Eli and Edythe Broad Center for Regenerative Medicine, UCLA, California 90095, USA [3] Jonsson Cancer Research Center, UCLA, California 90095, USA [4] Molecular Biology Institute, UCLA, California 90095, USA
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Chin CWL, Semple S, Malley T, White AC, Mirsadraee S, Weale PJ, Prasad S, Newby DE, Dweck MR. Optimization and comparison of myocardial T1 techniques at 3T in patients with aortic stenosis. Eur Heart J Cardiovasc Imaging 2013; 15:556-65. [PMID: 24282220 PMCID: PMC3979453 DOI: 10.1093/ehjci/jet245] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Aims To determine the optimal T1 mapping approach to assess myocardial fibrosis at 3T. Methods and results T1 mapping was performed at 3T using the modified look-locker-inversion sequence in 20 healthy volunteers and 20 patients with aortic stenosis (AS). Pre- and post-contrast myocardial T1, the partition coefficient (λ; ΔRmyocardium/ΔRblood, where ΔR = 1/post-contrast T1 − 1/pre-contrast T1), and extracellular volume fraction [ECV; λ (1 − haematocrit)] were assessed. After establishing the optimal time point and myocardial region for analysis, we compared the reproducibility of these T1 measures and their ability to differentiate asymptomatic patients with AS from healthy volunteers. There was no segmental variation across the ventricle in any of the T1 measures evaluated. λ and ECV did not vary with time, while post-contrast T1 was relatively constant between 15 and 30 min. Thus, mid-cavity myocardium at 20 min was used for subsequent analyses. ECV displayed excellent intra-, inter-observer, and scan–rescan reproducibility [intra-class correlation coefficients (ICC) 1.00, 0.97, and 0.96, respectively], as did λ (ICC 0.99, 0.94, 0.93, respectively). Moreover, ECV and λ were both higher in patients with AS compared with controls (ECV 28.3 ± 1.7 vs. 26.0 ± 1.6%, P < 0.001; λ 0.46 ± 0.03 vs. 0.44 ± 0.03, P = 0.02), with the former offering improved differentiation. In comparison, scan–rescan reproducibilities for pre- and post-contrast myocardial T1 were only modest (ICC 0.72 and 0.56) with no differences in values observed between cases and controls (both P> 0.05). Conclusions ECV appears to be the most promising measure of diffuse myocardial fibrosis at 3T based upon its superior reproducibility and ability to differentiate disease from health.
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Affiliation(s)
- Calvin W L Chin
- British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh, UK. Department of Cardiovascular Medicine, National Heart Center Singapore, Singapore
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Weigum SE, Castellanos-Gonzalez A, White AC, Richards-Kortum R. Amplification-free detection of Cryptosporidium parvum nucleic acids with the use of DNA/RNA-directed gold nanoparticle assemblies. J Parasitol 2013; 99:923-6. [PMID: 23617738 DOI: 10.1645/12-132.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
This study describes the development and evaluation of an amplification-free molecular assay for detection of Cryptosporidium parvum oocysts. The assay employed a pair of oligonucleotide-functionalized gold nanoparticle (AuNP) probes that were complementary to adjacent sequences on C. parvum 18s rRNA. Hybridization of the probes to the target RNA resulted in the assembly of AuNPs into target-linked networks, which were detected both visibly and spectroscopically, by a redshift in the wavelength of light scattered by the gold nanoparticles. The limit of detection was between 4 × 10(5) and 4 × 10(6) copies of RNA per microliter reaction mix, when a short synthetic target or full-length in vitro transcribed target was employed. With total nucleic acids purified from C. parvum oocysts spiked into 100-mg stool, as few as 670 oocysts/μl reaction mix were detected. The ability to detect the nucleic acids of C. parvum oocysts in stool, without the need for complex amplification, offers unique advantages for such AuNP aggregation assays to be extended toward use in resource-limited settings where protozoan detection is needed most.
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Affiliation(s)
- S E Weigum
- Department of Biology, Texas State University, San Marcos, Texas 78666
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White AC, Barenghi CF, Proukakis NP, Youd AJ, Wacks DH. Nonclassical velocity statistics in a turbulent atomic Bose-Einstein condensate. Phys Rev Lett 2010; 104:075301. [PMID: 20366893 DOI: 10.1103/physrevlett.104.075301] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Revised: 01/26/2010] [Indexed: 05/29/2023]
Abstract
In a recent experiment Paoletti [Phys. Rev. Lett. 101, 154501 (2008)]10.1103/PhysRevLett.101.154501 monitored the motion of tracer particles in turbulent superfluid helium and inferred that the velocity components do not obey the Gaussian statistics observed in ordinary turbulence. Motivated by their experiment, we create a small 3D turbulent state in an atomic Bose-Einstein condensate, compute directly the velocity field, and find similar nonclassical power-law tails. We obtain similar results in 2D trapped and 3D homogeneous condensates, and in classical 2D vortex points systems. This suggests that non-Gaussian turbulent velocity statistics describe a fundamental property of quantum turbulence. We also track the decay of the vortex tangle in the presence of the thermal cloud.
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Affiliation(s)
- A C White
- School of Mathematics and Statistics, Newcastle University, Newcastle upon Tyne, NE1 7RU, United Kingdom.
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Kovalszki A, Schumaker GL, Klein A, Terrin N, White AC. Reduced respiratory and skeletal muscle strength in survivors of sibling or unrelated donor hematopoietic stem cell transplantation. Bone Marrow Transplant 2008; 41:965-9. [PMID: 18264142 DOI: 10.1038/bmt.2008.15] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We performed a retrospective analysis of muscle strength testing obtained following sibling or unrelated donor hematopoietic stem cell transplant (HSCT) between 1 January 1999 and 31 December 2003 in a cohort of 44 subjects at Tufts-New England Medical Center. Maximal inspiratory pressure (PI(max)) was <or=80% predicted in 52% of subjects and <or=60% predicted in 20% of subjects; maximal expiratory pressure (PE(max)) was <or=80% predicted in 88% of subjects and <or=60% predicted in 74% of subjects. Patients with a PI(max) <or=60% predicted spent significantly longer time in hospital following HSCT compared with subjects with PI(max) 60% predicted. Grip strength (n=32) was reduced to <or=80% predicted in 75% of subjects and <or=60% predicted in 47% of subjects following HSCT. Analysis of paired measurements obtained before and after HSCT in 20 of the 44 subjects (45%) showed significant reduction in both PI(max) and PE(max) between the two measures. Respiratory and skeletal muscle weakness is present in a significant percentage of subjects undergoing pulmonary function testing in the post-HSCT period, and may contribute to pulmonary morbidity in subjects with pulmonary complications of HSCT.
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Affiliation(s)
- A Kovalszki
- Department of Medicine, Tufts-New England Medical Center, Tufts University School of Medicine, Boston, MA, USA
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Nash TE, Singh G, White AC, Rajshekhar V, Loeb JA, Proaño JV, Takayanagui OM, Gonzalez AE, Butman JA, DeGiorgio C, Del Brutto OH, Delgado-Escueta A, Evans CAW, Gilman RH, Martinez SM, Medina MT, Pretell EJ, Teale J, Garcia HH. Treatment of neurocysticercosis: current status and future research needs. Neurology 2006; 67:1120-7. [PMID: 17030744 PMCID: PMC2923067 DOI: 10.1212/01.wnl.0000238514.51747.3a] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Here we put forward a roadmap that summarizes important questions that need to be answered to determine more effective and safer treatments. A key concept in management of neurocysticercosis is the understanding that infection and disease due to neurocysticercosis are variable and thus different clinical approaches and treatments are required. Despite recent advances, treatments remain either suboptimal or based on poorly controlled or anecdotal experience. A better understanding of basic pathophysiologic mechanisms including parasite survival and evolution, nature of the inflammatory response, and the genesis of seizures, epilepsy, and mechanisms of anthelmintic action should lead to improved therapies.
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Affiliation(s)
- T E Nash
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, USA.
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White AC, Sousa AM, Blumberg J, Ryan HF, Fanburg BL, Kayyali US. Plasma antioxidants in subjects before hematopoietic stem cell transplantation. Bone Marrow Transplant 2006; 38:513-20. [PMID: 16980999 DOI: 10.1038/sj.bmt.1705475] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
UNLABELLED Chemo-irradiation induced oxidative damage to vascular endothelium may contribute to pulmonary complications of hematopoietic stem cell transplantation (HSCT). We measured antioxidants, markers of oxidative stress and plasma antioxidant capacity in plasma or serum from 24 subjects at day 7 before HSCT and 20 control subjects. The plasma concentration of extracellular glutathione peroxidase (GPX-3) was significantly reduced in the HSCT subjects compared with controls (HSCT: 98+/-42 microg/ml, control: 169+/-56 microg/ml, P<0.0001). The concentration of gamma-tocopherol was significantly higher in the HSCT subjects compared with controls (HSCT: 207+/-103 microg/dl; CONTROL 98+/-52 microg/dl; P=0.0002). The plasma concentrations of protein carbonyl, nitrotyrosine, malondialdehyde, alpha-tocopherol, vitamin A, homocysteine, cysteine and cysteinylglycine did not differ between HSCT and control subjects. Plasma from HSCT subjects was as effective as control plasma in quenching menadione-induced intracellular reactive oxygen species production in human microvascular endothelial cells. In summary, subjects before HSCT have significantly reduced plasma concentrations of GPX-3, elevated plasma gamma-tocopherol yet retains the ability to quench an acute oxidative stress. These changes may play a role in chronic oxidative stress in the HSCT population.
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Affiliation(s)
- A C White
- Pulmonary, Critical Care and Sleep Division, Department of Medicine, Tufts-New England Medical Center, Tupper Research Institute, Tufts University School of Medicine, Boston, MA, USA.
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Affiliation(s)
- C P Stewart
- The New Clinical Research Laboratory, Royal Infirmary of Edinburgh, and the Department of Pharmacology, Edinburgh University
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Affiliation(s)
- A C White
- The Department of Pharmacology, University of Edinburgh
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Affiliation(s)
- E Stedman
- The Department of Medical Chemistry, University of Edinburgh, and the Wellcome Physiological Research Laboratories, Langley Court, Beckenham
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Affiliation(s)
- C P Stewart
- The Departments of Therapeutics and Pharmacology, University of Edinburgh
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Baig S, Damian RT, Molinari JL, Tato P, Morales-Montor J, Welch M, Talhouk J, Hashmeys R, White AC. Purification and characterization of a metacestode cysteine proteinase from Taenia solium involved in the breakdown of human IgG. Parasitology 2005; 131:411-6. [PMID: 16178363 DOI: 10.1017/s0031182005007821] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Infection of the central nervous system by Taenia solium cysticerci is the cause of human neurocysticercosis, a major neurological infection in the Third World and an emerging infectious disease in the United States. We previously isolated a cysteine proteinase from cysticerci of Taenia crassiceps and demonstrated that it degrades human IgG in vitro. We have now isolated a 48 kDa thiol-dependent proteinase from T. solium. The T. solium enzyme also degrades human IgG, but does not significantly degrade albumin. IgG degradation was inhibited by cysteine proteinase inhibitors, but not significantly by inhibitors of aspartic, serine, or metalloproteinases. The peptide substrate specificity and pH optimum resemble cathepsin L. The Km for the peptide substrate Z-Phe-Arg-AFC was calculated to be 7.0 x 10(-6) M, the Kcat was 1.98 x 10(-5) s(-1), and the Kcat/Km 2.84 x 10(9) M(-1) s(-1), a value which is within the diffusion control limit for highly catalytic enzymes. We propose that immunoglobulin degradation by the T. solium cysteine proteinase may play a key role in the host-parasite interface and could be employed as a target for chemotherapy.
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Affiliation(s)
- S Baig
- Department of Cellular Biology, University of Georgia, Biological Sciences Building, Athens, GA 30603, USA
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Visnegarwala F, Graviss EA, Sajja P, Lahart CJ, White AC. Determinants of sustained virological suppression in indigent, HIV-infected patients: is single protease inhibitor-based antiretroviral therapy truly highly active? HIV Clin Trials 2004; 5:117-24. [PMID: 15248135 DOI: 10.1310/jq8u-6kvb-9jcg-jl51] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Effective virological suppression with HAART is dependent on strict adherence to therapy. Compliance with therapy is influenced by clinical and psychosocial factors. METHOD We performed a retrospective study investigating determinants of effective virological suppression, defined as <400 RNA at 11-13 months of HAART, in an urban indigent population. The study included 366 new patients presenting for care to the Thomas Street Clinic, Houston, Texas, between April and December 1998. Median age, CD4 count, and viral load (VL) of the study population were 37.5 years, 189 cells/mm(3), and 53,000, respectively. Thirty-nine percent had AIDS, 20% had cocaine-positive drug screens, and 64% were antiretroviral naïve. Two hundred and sixty-seven patients were started on HAART. Thirty-four percent showed virological suppression. RESULTS In multivariate analysis, adherence to HAART, care by experienced primary provider, baseline VL <100,000 copies/mL, age >35 years, and no active substance use were associated with virological suppression. Rates of virological suppression with HAART are unacceptably low in this urban indigent population. CONCLUSION Low rates of virological suppression are primarily due to lack of adherence rather than late utilization of care among ethnic minorities. Single protease-inhibitor-based antiretroviral therapy does not appear to be highly active in this patient population.
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Affiliation(s)
- F Visnegarwala
- Section of Infectious Diseases, Department of Medicine, Baylor College of Medicine, Houston, Texas, USA.
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Smith LA, Cowell SJ, White AC, Boon NA, Newby DE, Northridge DB. Contrast agent increases doppler velocities and improves reproducibility of aortic valve area measurements in patients with aortic stenosis. J Am Soc Echocardiogr 2004; 17:247-52. [PMID: 14981423 DOI: 10.1016/j.echo.2003.11.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [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: 10/25/2022]
Abstract
Observer variability may limit assessment of aortic stenosis by Doppler echocardiography. This study aimed to assess whether echocardiographic contrast agent improves reproducibility of aortic valve area (AVA) measurements for patients with aortic stenosis. In all, 20 patients with aortic stenosis (67 +/- 10 years old) underwent noncontrast and contrast Doppler echocardiography on 2 occasions, 3 weeks apart. Intraobserver and interobserver coefficients of reproducibility were 0.36 and 0.20 cm for left ventricular outflow tract (LVOT) diameter, and 0.38 and 0.24 cm(2) for AVA, respectively. Although intraobserver reproducibility was unaffected, contrast improved interobserver reproducibility for LVOT diameter (mean of differences -0.02 +/- 0.07 cm vs 0.01 +/- 0.10 cm, P <.05) and AVA (mean of differences 0.02 +/- 0.10 cm(2) vs 0.07 +/- 0.12 cm(2), P <.05). Prevalve and postvalve velocities were increased with contrast compared with noncontrast imaging (prevalve, 1.07 +/- 0.20 vs 0.94 +/- 0.19 m/s, P <.01; postvalve, 3.76 +/- 0.87 vs 3.47 +/- 0.78 m/s, P <.01). We conclude that contrast significantly increases Doppler velocities and produces modest improvements in reproducibility of LVOT diameter and AVA. We suggest that, when assessing patients with aortic stenosis, contrast agents should be considered in patients who are difficult to image with poor baseline LVOT images or Doppler studies, or where there is poor interobserver reproducibility.
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Affiliation(s)
- Lindsay A Smith
- Cardiovascular Research, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, Scotland, UK.
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Abstract
Neurocysticercosis is a common cause of neurological disease in developing countries and a major cause of epilepsy worldwide. A unique characteristic of human neurocysticercosis is that the living parasite is very well tolerated in human brain, so symptoms and clinical disease primarily result from death of the organism and accompanying inflammatory reaction in the human CNS. Among the diverse clinical manifestations of human neurocysticercosis, seizures are the most common, but other clinical problems occur, depending upon the localisation and viability of the parasite. Although both praziquantel and albendazole are effective agents, there is controversy about their role in several forms of the disease. Systematic reviews have pointed out the limited quality of available data on therapy. At a recent international conference convened to develop guidelines for treatment of this disease, areas of consensus and disagreement on the role of antiparasitic therapy were discussed. It was clear to all that cysticercosis cannot be regarded as a single disorder; treatment needs to be modified based on the location and number of cysticerci and the host response. There was a strong consensus that there is no role for antiparasitic drugs in patients with only calcified lesions. Studies suggest that patients with single enhancing lesions will do well regardless of antiparasitic therapy. Antiparasitic drugs are contraindicated in patients with cerebral oedema (cysticercal encephalitis). Most experts strongly recommend antiparasitic therapy in patients with multiple subarachnoid cysticerci or giant cysticerci. In patients with ventricular cysticerci, endoscopic removal is the preferred therapy. However, recent evidence suggests that placement of a ventricular shunt followed by antiparasitic therapy is an acceptable alternative. Standard treatment for localization-related epilepsy is effective for seizures caused by cysticercosis. In general, seizures are easily controlled in this illness. While many controversies regarding the treatment of patients with neurocysticercosis were not resolved at the international consensus conference, participants did conclude that controlled prospective studies are required to define optimal therapy for the infection and that treatment of infected individuals must be individualised.
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Affiliation(s)
- Terrence Riley
- Department of Neurology, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA.
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Abstract
Judgements about the health of clinical health care workers in relation to fitness to practice are made by a variety of doctors. These guidelines have been written to assist with such judgements and to facilitate equitable decision making in matters of employment.
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Affiliation(s)
- C J M Poole
- Dudley Priority Health NHS Trust, Health Centre, Cross Street, Dudley DY1 1RN, UK
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Del Brutto OH, Rajshekhar V, White AC, Tsang VC, Nash TE, Takayanagui OM, Schantz PM, Evans CA, Flisser A, Correa D, Botero D, Allan JC, Sarti E, Gonzalez AE, Gilman RH, García HH. Proposed diagnostic criteria for neurocysticercosis. Neurology 2001; 57:177-83. [PMID: 11480424 PMCID: PMC2912527 DOI: 10.1212/wnl.57.2.177] [Citation(s) in RCA: 489] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Neurocysticercosis is the most common helminthic infection of the CNS but its diagnosis remains difficult. Clinical manifestations are nonspecific, most neuroimaging findings are not pathognomonic, and some serologic tests have low sensitivity and specificity. The authors provide diagnostic criteria for neurocysticercosis based on objective clinical, imaging, immunologic, and epidemiologic data. These include four categories of criteria stratified on the basis of their diagnostic strength, including the following: 1) absolute--histologic demonstration of the parasite from biopsy of a brain or spinal cord lesion, cystic lesions showing the scolex on CT or MRI, and direct visualization of subretinal parasites by funduscopic examination; 2) major--lesions highly suggestive of neurocysticercosis on neuroimaging studies, positive serum enzyme-linked immunoelectrotransfer blot for the detection of anticysticercal antibodies, resolution of intracranial cystic lesions after therapy with albendazole or praziquantel, and spontaneous resolution of small single enhancing lesions; 3) minor--lesions compatible with neurocysticercosis on neuroimaging studies, clinical manifestations suggestive of neurocysticercosis, positive CSF enzyme-linked immunosorbent assay for detection of anticysticercal antibodies or cysticercal antigens, and cysticercosis outside the CNS; and 4) epidemiologic--evidence of a household contact with Taenia solium infection, individuals coming from or living in an area where cysticercosis is endemic, and history of frequent travel to disease-endemic areas. Interpretation of these criteria permits two degrees of diagnostic certainty: 1) definitive diagnosis, in patients who have one absolute criterion or in those who have two major plus one minor and one epidemiologic criterion; and 2) probable diagnosis, in patients who have one major plus two minor criteria, in those who have one major plus one minor and one epidemiologic criterion, and in those who have three minor plus one epidemiologic criterion.
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Affiliation(s)
- O H Del Brutto
- Department of Neurology, Hospital-Clinica Kennedy, Guayaquil, Ecuador.
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Robinson P, Okhuysen PC, Chappell CL, Lewis DE, Shahab I, Lahoti S, White AC. Expression of IL-15 and IL-4 in IFN-gamma-independent control of experimental human Cryptosporidium parvum infection. Cytokine 2001; 15:39-46. [PMID: 11509007 DOI: 10.1006/cyto.2001.0888] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have previously demonstrated interferon gamma (IFN-gamma) in intestinal mucosa after experimental human Cryptosporidium parvum infection, but expression was limited to sensitized volunteers. To characterize IFN-gamma-independent mechanisms in control of infection, jejunal biopsies from immunocompetent volunteers experimentally challenged with C. parvum were examined by in situ hybridization for interleukin (IL-)15 and IL-4 mRNA with confirmation by immunohistochemistry. Cytokine expression was correlated with prechallenge anti- C. parvum IgG, symptoms, oocyst shedding, and prior IFN-gamma expression data. IL-15 expression was noted only in those without prior sensitization, who did not express IFN-gamma. By contrast, expression of IL-4 was associated with prior sensitization. IL-15 was only detected in those with symptoms (6/14 symptomatic vs 0/3 asymptomatic, P<0.05). Among 14 volunteers who did not express IFN-gamma, oocyst shedding was lower in those expressing IL-15. Overall, 14/15 volunteers who did not shed oocysts expressed either IFN-gamma or IL-15. There was no correlation between expression of IL-4 and symptoms or oocyst shedding. In conclusion, IL-15 expression was associated with control of oocyst shedding in those not expressing IFN-gamma. These data suggest that IL-15 is involved in IFN-gamma independent mechanisms of control of human cryptosporidiosis, perhaps via activation of the innate immune response.
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Affiliation(s)
- P Robinson
- Department of Medicine, Baylor College of Medicine, Houston, TX 77030, USA
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Colvin JS, White AC, Pratt SJ, Ornitz DM. Lung hypoplasia and neonatal death inFgf9-null mice identify this gene as an essential regulator of lung mesenchyme. Development 2001; 128:2095-106. [PMID: 11493531 DOI: 10.1242/dev.128.11.2095] [Citation(s) in RCA: 247] [Impact Index Per Article: 10.7] [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: 12/17/2022]
Abstract
Mammalian lung develops as an evagination of ventral gut endoderm into the underlying mesenchyme. Iterative epithelial branching, regulated by the surrounding mesenchyme, generates an elaborate network of airways from the initial lung bud. Fibroblast growth factors (FGFs) often mediate epithelial-mesenchymal interactions and mesenchymal Fgf10 is essential for epithelial branching in the developing lung. However, no FGF has been shown to regulate lung mesenchyme. In embryonic lung, Fgf9 is detected in airway epithelium and visceral pleura at E10.5, but is restricted to the pleura by E12.5. We report that mice homozygous for a targeted disruption of Fgf9 exhibit lung hypoplasia and early postnatal death. Fgf9−/− lungs exhibit reduced mesenchyme and decreased branching of airways, but show significant distal airspace formation and pneumocyte differentiation. Our results suggest that Fgf9 affects lung size by stimulating mesenchymal proliferation. The reduction in the amount of mesenchyme in Fgf9−/− lungs limits expression of mesenchymal Fgf10. We suggest a model whereby FGF9 signaling from the epithelium and reciprocal FGF10 signaling from the mesenchyme coordinately regulate epithelial airway branching and organ size during lung embryogenesis.
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Affiliation(s)
- J S Colvin
- Department of Molecular Biology and Pharmacology, Washington University Medical School, Campus Box 8103, 660 S. Euclid Avenue, St Louis, MO 63110, USA
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Abstract
Hypoxemia is a prevalent problem in the chronically critically ill patient. This article reviews the pathophysiologic mechanisms of hypoxemia in this patient population, discusses how oxygenation is evaluated, and reviews methods for delivery of oxygen. Other topics directly related to oxygen use, such as oxygen toxicity, heliox use, and portable oxygen devices, are included.
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Affiliation(s)
- A C White
- Department of Medicine, Pulmonary and Critical Care Division, New England Medical Center, Tufts University School of Medicine, Boston, Massachusetts, USA.
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Robinson P, Okhuysen PC, Chappell CL, Lewis DE, Shahab I, Janecki A, White AC. Expression of tumor necrosis factor alpha and interleukin 1 beta in jejuna of volunteers after experimental challenge with Cryptosporidium parvum correlates with exposure but not with symptoms. Infect Immun 2001; 69:1172-4. [PMID: 11160015 PMCID: PMC97999 DOI: 10.1128/iai.69.2.1172-1174.2001] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Jejunal biopsies from volunteers challenged with Cryptosporidium parvum were examined for tumor necrosis factor alpha (TNF-alpha) and interleukin (IL)-1 beta mRNA. Postchallenge biopsies from 15 of 28 (54%) volunteers expressed TNF-alpha; 14% expressed IL-1 beta. Cytokine expression did not correlate with enteric symptoms, suggesting that TNF-alpha and IL-1 beta are not key mediators of diarrhea in human cryptosporidiosis.
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Affiliation(s)
- P Robinson
- Department of Medicine, Baylor College of Medicine, Houston, Texas 77030, USA
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Murphy RL, Brun S, Hicks C, Eron JJ, Gulick R, King M, White AC, Benson C, Thompson M, Kessler HA, Hammer S, Bertz R, Hsu A, Japour A, Sun E. ABT-378/ritonavir plus stavudine and lamivudine for the treatment of antiretroviral-naive adults with HIV-1 infection: 48-week results. AIDS 2001; 15:F1-9. [PMID: 11192874 DOI: 10.1097/00002030-200101050-00002] [Citation(s) in RCA: 173] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To evaluate the safety and antiviral activity of different dose levels of the HIV protease inhibitor ABT-378 combined with low-dose ritonavir, plus stavudine and lamivudine in antiretroviral-naive individuals. DESIGN Prospective, randomized, double-blind, multicenter. METHODS Eligible patients with plasma HIV-1 RNA > 5000 copies/ml received ABT-378 200 or 400 mg with ritonavir 100 mg every 12 h; after 3 weeks stavudine 40 mg and lamivudine 150 mg every 12 h were added (group I, n = 32). A second group initiated treatment with ABT-378 400 mg and ritonavir 100 or 200 mg plus stavudine and lamivudine every 12 h (group II, n = 68). RESULTS Mean baseline HIV-1 RNA was 4.9 log10 copies/ml in both groups and CD4 cell count was 398 x 10(6)/l and 310 x 10(6)/l in Groups I and II respectively. In the intent-to-treat (ITT; missing value = failure) analysis at 48 weeks, HIV-1 RNA was < 400 copies/ml for 91% (< 50 copies/ml, 75%) and 82% (< 50 copies/ml, 79%) of patients in groups I and II respectively. Mean steady-state ABT-378 trough concentrations exceeded the wild-type HIV-1 EC50 (effective concentration to inhibit 50%) by 50-100-fold. The most common adverse events were abnormal stools, diarrhea and nausea. No patient discontinued before 48 weeks because of treatment-related toxicity or virologic rebound. CONCLUSIONS ABT-378 is a potent, well-tolerated protease inhibitor. The activity and durable suppression of HIV-1 observed in this study is probably attributable to the observed tolerability profile and the achievement of high ABT-378 plasma concentrations.
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Affiliation(s)
- R L Murphy
- Department of Medicine, Northwestern University, Chicago, IL 60611, USA
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Sharma MD, Sagar B, Wang S, White AC, Balasubramanyam A. High frequency of serious infections in patients with panhypopituitarism: a case-control study. Clin Infect Dis 2001; 32:153-8. [PMID: 11112672 DOI: 10.1086/317533] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2000] [Revised: 05/19/2000] [Indexed: 11/04/2022] Open
Abstract
We reviewed the records of 65 patients with panhypopituitarism (PHP) for the frequency and types of infections requiring hospitalization, and documented serious infections in 13 of 65 patients with PHP. The increased frequency of serious infectious diseases in patients with PHP is likely to contribute to increased age-specific mortality.
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Affiliation(s)
- M D Sharma
- Division of Endocrinology, Baylor College of Medicine, Houston, TX 77030, USA.
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Dunne M, Fessel J, Kumar P, Dickenson G, Keiser P, Boulos M, Mogyros M, White AC, Cahn P, O'Connor M, Lewi D, Green S, Tilles J, Hicks C, Bissett J, Schneider MM, Benner R. A randomized, double-blind trial comparing azithromycin and clarithromycin in the treatment of disseminated Mycobacterium avium infection in patients with human immunodeficiency virus. Clin Infect Dis 2000; 31:1245-52. [PMID: 11073759 DOI: 10.1086/317468] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/1999] [Revised: 05/24/2000] [Indexed: 11/04/2022] Open
Abstract
Two hundred and forty-six patients infected with human immunodeficiency virus (HIV) who also had disseminated Mycobacterium avium complex received either azithromycin 250 mg every day, azithromycin 600 mg every day, or clarithromycin 500 mg twice a day, each combined with ethambutol, for 24 weeks. Samples drawn from patients were cultured and clinically assessed every 3 weeks up to week 12, then monthly thereafter through week 24 of double-blind therapy and every 3 months while on open-label therapy through the conclusion of the trial. The azithromycin 250 mg arm of the study was dropped after an interim analysis showed a lower rate of clearance of bacteremia. At 24 weeks of therapy, the likelihood of patients' developing 2 consecutive negative cultures (46% vs. 56%, P=.24) or 1 negative culture (59% vs. 61%, P=.80) was similar for azithromycin 600 mg (n=68) and clarithromycin (n=57), respectively. The likelihood of relapse was 39% versus 27% (P=.21) on azithromycin compared with clarithromycin, respectively. Of the 6 patients who experienced relapse, none of those randomized to receive azithromycin developed isolates resistant to macrolides, compared with 2 of 3 patients randomized to receive clarithromycin [corrected]. Mortality was similar in patients comprising each arm of the study (69% vs. 63%; hazard, 95.1% confidence interval, 1.1 [0.7, 1.7]). Azithromycin 600 mg, when given in combination with ethambutol, is an effective agent for the treatment of disseminated M. avium disease in patients infected with HIV.
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Affiliation(s)
- M Dunne
- Pfizer Central Research, Groton, CT 06340, USA.
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Leano AM, Miller K, White AC. Chronic graft-versus-host disease-related polymyositis as a cause of respiratory failure following allogeneic bone marrow transplant. Bone Marrow Transplant 2000; 26:1117-20. [PMID: 11108314 DOI: 10.1038/sj.bmt.1702688] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
An unusual case of respiratory failure and dropped head syndrome as a complication of severe chronic graft-versus-host disease (GVHD)-related polymyositis is described. The patient required tracheostomy and mechanical ventilation but recovered following treatment with aggressive immunosuppression and intensive rehabilitation. The differential diagnoses of muscle weakness in the bone marrow transplant (BMT) patient and the dropped head syndrome are both discussed. To our knowledge, this is the first reported case of respiratory failure requiring mechanical ventilation occurring as a complication of GVHD-related polymyositis.
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Affiliation(s)
- A M Leano
- Department of Medicine, New England Medical Center, Tufts University School of Medicine, Tupper Research Institute, Boston, MA 02111, USA
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Haas DW, Arathoon E, Thompson MA, de Jesus Pedro R, Gallant JE, Uip DE, Currier J, Noriega LM, Lewi DS, Uribe P, Benetucci L, Cahn P, Paar D, White AC, Collier AC, Ramirez-Ronda CH, Harvey C, Chung MO, Mehrotra D, Chodakewitz J, Nguyen BY. Comparative studies of two-times-daily versus three-times-daily indinavir in combination with zidovudine and lamivudine. AIDS 2000; 14:1973-8. [PMID: 10997402 DOI: 10.1097/00002030-200009080-00013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES To compare the efficacy and safety of two-times-daily versus three-times-daily indinavir in combination with zidovudine and lamivudine. DESIGN Two multicenter, open-label, randomized 24-week studies. METHODS Adults HIV-1 infection, HIV-1 RNA greater than 10000 copies/ml, and no prior lamivudine or protease inhibitor therapy were eligible. In a pilot study (Study A), patients received indinavir at 800 mg every 8 h, 1000 mg every 12 h, or 1200 mg every 12 h. In a subsequent study (Study B), patients received indinavir at 800 mg every 8 h or 1200 mg every 12 h. All subjects received zidovudine (300 mg) and lamivudine (150 mg) every 12 h. An intent-to-treat analysis was used. RESULTS In Study A, which enrolled 88 patients, neither HIV-1 RNA nor CD4 cell responses differed significantly between treatment groups at 24 weeks when corrected for multiple comparisons. Study B enrolled 433 patients, but was prematurely discontinued when interim analysis suggested greater efficacy of three-times-daily indinavir. Of the first 87 patients reaching week 24, HIV-1 RNA was less than 400 copies/ml in 91% receiving three-times-daily versus 64% receiving two-times-daily indinavir (P < 0.01). CONCLUSION Three-times-daily indinavir appears more efficacious than two-times-daily dosing when administered with zidovudine and lamivudine. Two-times-daily indinavir dosing should only be considered in situations characterized by favorable pharmacokinetic drug-drug interactions.
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Affiliation(s)
- D W Haas
- Vanderbilt University School of Medicine, Nashville, Tennessee 37212, USA.
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50
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Robinson P, Okhuysen PC, Chappell CL, Lewis DE, Shahab I, Lahoti S, White AC. Transforming growth factor beta1 is expressed in the jejunum after experimental Cryptosporidium parvum infection in humans. Infect Immun 2000; 68:5405-7. [PMID: 10948171 PMCID: PMC101805 DOI: 10.1128/iai.68.9.5405-5407.2000] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Biopsies from volunteers challenged with Cryptosporidium parvum were examined for transforming growth factor beta1 (TGF-beta1). None of the prechallenge biopsies exhibited TGF-beta. Seven of 12 volunteers with oocyst shedding expressed TGF-beta versus 2 of 13 volunteers without detected oocysts. The association of TGF-beta expression with oocyst excretion and the timing of symptoms suggests that TGF-beta mediates intestinal healing.
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Affiliation(s)
- P Robinson
- Department of Molecular Virology, Baylor College of Medicine, Houston, Texas 77030, USA
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