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Mesnier J, Simard T, Jung RG, Lehenbauer KR, Piayda K, Pracon R, Jackson GG, Flores-Umanzor E, Faroux L, Korsholm K, Chun JKR, Chen S, Maarse M, Montrella K, Chaker Z, Spoon JN, Pastormerlo LE, Meincke F, Sawant AC, Moldovan CM, Qintar M, Aktas MK, Branca L, Radinovic A, Ram P, El-Zein RS, Flautt T, Ding WY, Sayegh B, Benito-González T, Lee OH, Badejoko SO, Paitazoglou C, Karim N, Zaghloul AM, Agarwal H, Kaplan RM, Alli O, Ahmed A, Suradi HS, Knight BP, Alla VM, Panaich SS, Wong T, Bergmann MW, Chothia R, Kim JS, Pérez de Prado A, Bazaz R, Gupta D, Valderrábano M, Sanchez CE, El Chami MF, Mazzone P, Adamo M, Ling F, Wang DD, O'Neill W, Wojakowski W, Pershad A, Berti S, Spoon DB, Kawsara A, Jabbour G, Boersma LVA, Schmidt B, Nielsen-Kudsk JE, Freixa X, Ellis CR, Fauchier L, Demkow M, Sievert H, Main ML, Hibbert B, Holmes DR, Alkhouli M, Rodés-Cabau J. Persistent and Recurrent Device-Related Thrombus After Left Atrial Appendage Closure: Incidence, Predictors, and Outcomes. JACC Cardiovasc Interv 2023; 16:2722-2732. [PMID: 38030358 DOI: 10.1016/j.jcin.2023.09.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 09/05/2023] [Accepted: 09/11/2023] [Indexed: 12/01/2023]
Abstract
BACKGROUND Scarce data exist on the evolution of device-related thrombus (DRT) after left atrial appendage closure (LAAC). OBJECTIVES This study sought to assess the incidence, predictors, and clinical impact of persistent and recurrent DRT in LAAC recipients. METHODS Data were obtained from an international multicenter registry including 237 patients diagnosed with DRT after LAAC. Of these, 214 patients with a subsequent imaging examination after the initial diagnosis of DRT were included. Unfavorable evolution of DRT was defined as either persisting or recurrent DRT. RESULTS DRT resolved in 153 (71.5%) cases and persisted in 61 (28.5%) cases. Larger DRT size (OR per 1-mm increase: 1.08; 95% CI: 1.02-1.15; P = 0.009) and female (OR: 2.44; 95% CI: 1.12-5.26; P = 0.02) were independently associated with persistent DRT. After DRT resolution, 82 (53.6%) of 153 patients had repeated device imaging, with 14 (17.1%) cases diagnosed with recurrent DRT. Overall, 75 (35.0%) patients had unfavorable evolution of DRT, and the sole predictor was average thrombus size at initial diagnosis (OR per 1-mm increase: 1.09; 95% CI: 1.03-1.16; P = 0.003), with an optimal cutoff size of 7 mm (OR: 2.51; 95% CI: 1.39-4.52; P = 0.002). Unfavorable evolution of DRT was associated with a higher rate of thromboembolic events compared with resolved DRT (26.7% vs 15.1%; HR: 2.13; 95% CI: 1.15-3.94; P = 0.02). CONCLUSIONS About one-third of DRT events had an unfavorable evolution (either persisting or recurring), with a larger initial thrombus size (particularly >7 mm) portending an increased risk. Unfavorable evolution of DRT was associated with a 2-fold higher risk of thromboembolic events compared with resolved DRT.
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Affiliation(s)
- Jules Mesnier
- Quebec Heart and Lung Institute, Laval University, Quebec City, Quebec, Canada
| | - Trevor Simard
- Department of Cardiovascular Diseases, Mayo Clinic School of Medicine, Rochester, Minnesota, USA
| | - Richard G Jung
- Capital Research Group, University of Ottawa Heart Institute, Ottawa, Ontario, Canada
| | - Kyle R Lehenbauer
- Division of Cardiology, Saint Luke's Mid America Heart Institute, Kansas City, Missouri, USA
| | - Kerstin Piayda
- CardioVascular Center Frankfurt, Frankfurt, Germany; Department of Cardiology and Angiology, Universitätsklinikum Gießen und Marburg, Gießen, Germany
| | - Radoslaw Pracon
- Coronary and Structural Heart Diseases Department, National Institute of Cardiology, Warsaw, Poland
| | | | - Eduardo Flores-Umanzor
- Department of Cardiology, Hospital Clínic of Barcelona, August Pi i Sunyer Biomedical Research Institute, University of Barcelona, Barcelona, Spain
| | - Laurent Faroux
- Quebec Heart and Lung Institute, Laval University, Quebec City, Quebec, Canada
| | - Kasper Korsholm
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | - Julian K R Chun
- Cardioangiologisches Centrum Bethanien, Medizinische Klinik III, Markuskrankenhaus, Frankfurt, Germany
| | - Shaojie Chen
- Cardioangiologisches Centrum Bethanien, Medizinische Klinik III, Markuskrankenhaus, Frankfurt, Germany
| | - Moniek Maarse
- Cardiology, St Antonius Hospital, Nieuwegein, the Netherlands; LB Amsterdam University Medical Center, Amsterdam, the Netherlands
| | - Kristi Montrella
- Heart and Vascular Institute, University of Pittsburgh Medical Center, University of Pittsburgh, Altoona, Pennsylvania, USA
| | - Zakeih Chaker
- Division of Cardiology, West Virginia School of Medicine, Morgantown, West Virginia, USA
| | - Jocelyn N Spoon
- International Heart Institute of Montana, Missoula, Montana, USA
| | - Luigi E Pastormerlo
- Fondazione Toscana Gabriele Monasterio Massa, Scuola Superiore Sant'Anna, Pisa, Italy
| | | | | | - Carmen M Moldovan
- Division of Cardiology and Structural Heart Diseases, Medical University of Silesia, Katowice, Poland
| | - Mohammed Qintar
- Division of Cardiology, Henry Ford Health System, Detroit, Michigan, USA; Department of Cardiology, Sparrow Hospital, Michigan State University, Lansing, Michigan
| | - Mehmet K Aktas
- Division of Cardiology, University of Rochester Medical Center, Rochester, New York, USA
| | - Luca Branca
- Cardiac Catheterization Laboratory and Cardiology, ASST Spedali Civili di Brescia, Department of Medical and Surgical Specialties, Radiological Sciences, and Public Health, University of Brescia, Brescia, Italy
| | - Andrea Radinovic
- Arrhythmology Department, San Raffaele University Hospital, Milan, Italy
| | - Pradhum Ram
- Emory University Hospital, Atlanta, Georgia, USA
| | - Rayan S El-Zein
- Division of Cardiology, OhioHealth Doctors Hospital/OhioHealth Riverside Methodist Hospital, Columbus, Ohio, USA
| | | | - Wern Yew Ding
- Liverpool Heart and Chest Hospital, Liverpool, United Kingdom
| | - Bassel Sayegh
- Heart, Lung and Vascular Institute, Excela Health, Independence Health System, Pittsburgh, Pennsylvania, USA
| | | | - Oh-Hyun Lee
- Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Solomon O Badejoko
- Division of Internal Medicine, St Joseph's Medical Center (Dignity Health), Stockton, California, USA
| | | | - Nabeela Karim
- Royal Brompton and Harefield Hospitals, Part of Guys' and St Thomas' National Health Service Foundation Trust, London, United Kingdom
| | - Ahmed M Zaghloul
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | | | - Rachel M Kaplan
- Bluhm Cardiovascular Institute, Northwestern University, Chicago, Illinois, USA
| | - Oluseun Alli
- Division of Cardiology, Novant Health Heart and Vascular Institute, Charlotte, North Carolina, USA
| | - Aamir Ahmed
- Rush University Medical Center, Chicago, Illinois, USA
| | | | - Bradley P Knight
- Bluhm Cardiovascular Institute, Northwestern University, Chicago, Illinois, USA
| | - Venkata M Alla
- Creighton University School of Medicine, Omaha, Nebraska, USA
| | - Sidakpal S Panaich
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Tom Wong
- Royal Brompton and Harefield Hospitals, Part of Guys' and St Thomas' National Health Service Foundation Trust, London, United Kingdom
| | | | - Rashaad Chothia
- Division of Internal Medicine, St Joseph's Medical Center (Dignity Health), Stockton, California, USA
| | - Jung-Sun Kim
- Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Seoul, Korea
| | | | - Raveen Bazaz
- Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Dhiraj Gupta
- Liverpool Heart and Chest Hospital, Liverpool, United Kingdom
| | | | - Carlos E Sanchez
- Division of Cardiology, OhioHealth Doctors Hospital/OhioHealth Riverside Methodist Hospital, Columbus, Ohio, USA
| | | | - Patrizio Mazzone
- Electrophysiology Unit, Cardio-Thoraco-Vascular Department, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Marianna Adamo
- Cardiac Catheterization Laboratory and Cardiology, ASST Spedali Civili di Brescia, Department of Medical and Surgical Specialties, Radiological Sciences, and Public Health, University of Brescia, Brescia, Italy
| | - Fred Ling
- Division of Cardiology, University of Rochester Medical Center, Rochester, New York, USA
| | - Dee Dee Wang
- Division of Cardiology, Henry Ford Health System, Detroit, Michigan, USA
| | - William O'Neill
- Division of Cardiology, Henry Ford Health System, Detroit, Michigan, USA
| | - Wojtek Wojakowski
- Division of Cardiology and Structural Heart Diseases, Medical University of Silesia, Katowice, Poland
| | - Ashish Pershad
- Chandler Regional Medical Center, Chandler, Arizona, USA
| | - Sergio Berti
- Fondazione Toscana Gabriele Monasterio Massa, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Daniel B Spoon
- International Heart Institute of Montana, Missoula, Montana, USA
| | - Akram Kawsara
- Division of Cardiology, West Virginia School of Medicine, Morgantown, West Virginia, USA
| | - George Jabbour
- Heart and Vascular Institute, University of Pittsburgh Medical Center, University of Pittsburgh, Altoona, Pennsylvania, USA
| | - Lucas V A Boersma
- Cardiology, St Antonius Hospital, Nieuwegein, the Netherlands; LB Amsterdam University Medical Center, Amsterdam, the Netherlands
| | - Boris Schmidt
- Cardioangiologisches Centrum Bethanien, Medizinische Klinik III, Markuskrankenhaus, Frankfurt, Germany
| | | | - Xavier Freixa
- Department of Cardiology, Hospital Clínic of Barcelona, August Pi i Sunyer Biomedical Research Institute, University of Barcelona, Barcelona, Spain
| | | | - Laurent Fauchier
- Service de Cardiologie, Centre Hospitalier Universitaire Trousseau Faculté de Médecine, Université François Rabelais, Tours, France
| | - Marcin Demkow
- Coronary and Structural Heart Diseases Department, National Institute of Cardiology, Warsaw, Poland
| | - Horst Sievert
- Heart, Lung and Vascular Institute, Excela Health, Independence Health System, Pittsburgh, Pennsylvania, USA
| | - Michael L Main
- Division of Cardiology, Saint Luke's Mid America Heart Institute, Kansas City, Missouri, USA
| | - Benjamin Hibbert
- Capital Research Group, University of Ottawa Heart Institute, Ottawa, Ontario, Canada
| | - David R Holmes
- Department of Cardiovascular Diseases, Mayo Clinic School of Medicine, Rochester, Minnesota, USA
| | - Mohamad Alkhouli
- Department of Cardiovascular Diseases, Mayo Clinic School of Medicine, Rochester, Minnesota, USA.
| | - Josep Rodés-Cabau
- Quebec Heart and Lung Institute, Laval University, Quebec City, Quebec, Canada; Department of Cardiology, Hospital Clínic of Barcelona, August Pi i Sunyer Biomedical Research Institute, University of Barcelona, Barcelona, Spain.
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Vega J, Carrasco A, Karim N, Stewart M, Bell W. Recurrent cerebellar ischemic infarctions and stereotyped peri-ictal sympathetic responses in a near-SUDEP patient with cardiovascular risk factors. Epilepsy Behav Rep 2023; 23:100605. [PMID: 37332897 PMCID: PMC10276251 DOI: 10.1016/j.ebr.2023.100605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/02/2023] [Accepted: 05/04/2023] [Indexed: 06/20/2023] Open
Abstract
We report a 60-year-old woman who presented to the emergency department after experiencing a witnessed unknown onset bilateral tonic clonic seizure (GTCS) that culminated in cardiac arrest. A neurology consultant uncovered a years-long history of frequent episodic staring followed by confusion and expressive aphasia, which strongly suggested that she suffered from epilepsy. Thus, her cardiac arrest and subsequent resuscitation met criteria for a near-sudden unexpected death in epilepsy (SUDEP) diagnosis. Serial bloodwork demonstrated transient troponin I elevations and leukocytoses, while a brain MRI revealed global cerebral anoxic injury and a small acute right cerebellar ischemic infarction. A review of her medical record uncovered a hospitalization sixteen months earlier for a likely GTCS whose workup showed similar troponin I elevations and leukocytoses, and surprisingly, a different small acute right cerebellar ischemic infarction in the same vascular territory. To our knowledge, this is the first report of subcortical ischemic infarctions occurring concurrently with GTCSs in a near-SUDEP patient. Aside from illustrating the key role of inpatient neurologists in the diagnosis of near-SUDEP, this manuscript discusses the potential significance of postictal ischemic infarctions, transient asymptomatic troponin elevations, and transient non-infectious leukocytoses in epilepsy patients with cardiovascular risk factors.
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Affiliation(s)
- J.L. Vega
- East Carolina University Medical Center, Greenville, NC, United States
- TeleNeurologia SAS, Medellin, Colombia
| | - A. Carrasco
- Brody School of Medicine, East Carolina University, Greenville, NC, United States
| | - N. Karim
- East Carolina University Medical Center, Greenville, NC, United States
| | - M. Stewart
- Departments of Neurology, State University of New York Health Sciences University, Brooklyn, NY, United States
- Physiology and Pharmacology, State University of New York Health Sciences University, Brooklyn, NY, United States
| | - W. Bell
- Brody School of Medicine, East Carolina University, Greenville, NC, United States
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Griffiths S, Behar JM, Kramer DB, Debney MT, Monkhouse C, Lefas AY, Lowe M, Amin F, Cantor E, Boyalla V, Karim N, Till J, Markides V, Clague JR, Wong T. The long-term outcomes of cardiac implantable electronic devices implanted via the femoral route. Pacing Clin Electrophysiol 2022; 45:481-490. [PMID: 35043404 PMCID: PMC9305836 DOI: 10.1111/pace.14449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 12/17/2021] [Accepted: 01/16/2022] [Indexed: 11/28/2022]
Abstract
Background Conventional superior access for cardiac implantable electronic devices (CIEDs) is not always possible and femoral CIEDs (F‐CIED) are an alternative option when leadless systems are not suitable. The long‐term outcomes and extraction experiences with F‐CIEDs, in particular complex F‐CIED (ICD/CRT devices), remain poorly understood. Methods Patients referred for F‐CIEDs implantation between 2002 and 2019 at two tertiary centers were included. Early complications were defined as ≤30 days following implant and late complications >30 days. Results Thirty‐one patients (66% male; age 56 ± 20 years; 35% [11] patients with congenital heart disease) were implanted with F‐CIEDs (10 ICD/CRT and 21 pacemakers). Early complications were observed in 6.5% of patients: two lead displacements. Late complications at 6.8 ± 4.4 years occurred in 29.0% of patients. This was higher with complex F‐CIED compared to simple F‐CIED (60.0% vs. 14.3%, p = .02). Late complications were predominantly generator site related (n = 8, 25.8%) including seven infections/erosions and one generator migration. Eight femoral generators and 14 leads (median duration in situ seven [range 6–11] years) were extracted without complication. Conclusions Procedural success with F‐CIEDs is high with clinically acceptable early complication rates. There is a notable risk of late complications, particularly involving the generator site of complex devices following repeat femoral procedures. Extraction of chronic F‐CIED in experienced centers is feasible and safe.
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Affiliation(s)
- Samuel Griffiths
- Royal Brompton Hospital, Royal Brompton & Harefield NHS Trust, Sydney Street, London, SW3 6NP, UK
| | - Jonathan M Behar
- Royal Brompton Hospital, Royal Brompton & Harefield NHS Trust, Sydney Street, London, SW3 6NP, UK
| | - Daniel B Kramer
- Richard A. and Susan F. Smith Center for Outcomes Research in Cardiology, Beth Israel Deaconess Medical Center & Harvard Medical School, Boston, MA, USA
| | - Mike T Debney
- Royal Brompton Hospital, Royal Brompton & Harefield NHS Trust, Sydney Street, London, SW3 6NP, UK
| | | | - Alicia Y Lefas
- Royal Brompton Hospital, Royal Brompton & Harefield NHS Trust, Sydney Street, London, SW3 6NP, UK
| | - Martin Lowe
- Barts Heart Centre, West Smithfields, London, EC1A 7BE, UK
| | - Fouad Amin
- Wexham Park Hospital, Frimley Health NHS Foundation Trust, Frimley, UK
| | - Emily Cantor
- Royal Brompton Hospital, Royal Brompton & Harefield NHS Trust, Sydney Street, London, SW3 6NP, UK
| | - Vennella Boyalla
- Royal Brompton Hospital, Royal Brompton & Harefield NHS Trust, Sydney Street, London, SW3 6NP, UK
| | - Nabeela Karim
- Royal Brompton Hospital, Royal Brompton & Harefield NHS Trust, Sydney Street, London, SW3 6NP, UK
| | - Jan Till
- Royal Brompton Hospital, Royal Brompton & Harefield NHS Trust, Sydney Street, London, SW3 6NP, UK
| | - Vias Markides
- Royal Brompton Hospital, Royal Brompton & Harefield NHS Trust, Sydney Street, London, SW3 6NP, UK
| | - Jonathan R Clague
- Royal Brompton Hospital, Royal Brompton & Harefield NHS Trust, Sydney Street, London, SW3 6NP, UK
| | - Tom Wong
- Royal Brompton Hospital, Royal Brompton & Harefield NHS Trust, Sydney Street, London, SW3 6NP, UK
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4
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Simard T, Jung RG, Lehenbauer K, Piayda K, Pracoń R, Jackson GG, Flores-Umanzor E, Faroux L, Korsholm K, Chun JKR, Chen S, Maarse M, Montrella K, Chaker Z, Spoon JN, Pastormerlo LE, Meincke F, Sawant AC, Moldovan CM, Qintar M, Aktas MK, Branca L, Radinovic A, Ram P, El-Zein RS, Flautt T, Ding WY, Sayegh B, Benito-González T, Lee OH, Badejoko SO, Paitazoglou C, Karim N, Zaghloul AM, Agrawal H, Kaplan RM, Alli O, Ahmed A, Suradi HS, Knight BP, Alla VM, Panaich SS, Wong T, Bergmann MW, Chothia R, Kim JS, Pérez de Prado A, Bazaz R, Gupta D, Valderrabano M, Sanchez CE, El Chami MF, Mazzone P, Adamo M, Ling F, Wang DD, O'Neill W, Wojakowski W, Pershad A, Berti S, Spoon D, Kawsara A, Jabbour G, Boersma LVA, Schmidt B, Nielsen-Kudsk JE, Rodés-Cabau J, Freixa X, Ellis CR, Fauchier L, Demkow M, Sievert H, Main ML, Hibbert B, Holmes DR, Alkhouli M. Predictors of Device-Related Thrombus Following Percutaneous Left Atrial Appendage Occlusion. J Am Coll Cardiol 2021; 78:297-313. [PMID: 34294267 DOI: 10.1016/j.jacc.2021.04.098] [Citation(s) in RCA: 92] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 04/05/2021] [Accepted: 04/29/2021] [Indexed: 12/20/2022]
Abstract
BACKGROUND Device-related thrombus (DRT) has been considered an Achilles' heel of left atrial appendage occlusion (LAAO). However, data on DRT prediction remain limited. OBJECTIVES This study constructed a DRT registry via a multicenter collaboration aimed to assess outcomes and predictors of DRT. METHODS Thirty-seven international centers contributed LAAO cases with and without DRT (device-matched and temporally related to the DRT cases). This study described the management patterns and mid-term outcomes of DRT and assessed patient and procedural predictors of DRT. RESULTS A total of 711 patients (237 with and 474 without DRT) were included. Follow-up duration was similar in the DRT and no-DRT groups, median 1.8 years (interquartile range: 0.9-3.0 years) versus 1.6 years (interquartile range: 1.0-2.9 years), respectively (P = 0.76). DRTs were detected between days 0 to 45, 45 to 180, 180 to 365, and >365 in 24.9%, 38.8%, 16.0%, and 20.3% of patients. DRT presence was associated with a higher risk of the composite endpoint of death, ischemic stroke, or systemic embolization (HR: 2.37; 95% CI, 1.58-3.56; P < 0.001) driven by ischemic stroke (HR: 3.49; 95% CI: 1.35-9.00; P = 0.01). At last known follow-up, 25.3% of patients had DRT. Discharge medications after LAAO did not have an impact on DRT. Multivariable analysis identified 5 DRT risk factors: hypercoagulability disorder (odds ratio [OR]: 17.50; 95% CI: 3.39-90.45), pericardial effusion (OR: 13.45; 95% CI: 1.46-123.52), renal insufficiency (OR: 4.02; 95% CI: 1.22-13.25), implantation depth >10 mm from the pulmonary vein limbus (OR: 2.41; 95% CI: 1.57-3.69), and non-paroxysmal atrial fibrillation (OR: 1.90; 95% CI: 1.22-2.97). Following conversion to risk factor points, patients with ≥2 risk points for DRT had a 2.1-fold increased risk of DRT compared with those without any risk factors. CONCLUSIONS DRT after LAAO is associated with ischemic events. Patient- and procedure-specific factors are associated with the risk of DRT and may aid in risk stratification of patients referred for LAAO.
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Affiliation(s)
- Trevor Simard
- Department of Cardiovascular Diseases, Mayo Clinic School of Medicine, Rochester, Minnesota, USA. https://twitter.com/tjsimard
| | - Richard G Jung
- Capital Research Group, University of Ottawa Heart Institute, Ottawa, Ontario, Canada
| | - Kyle Lehenbauer
- Division of Cardiology, Saint Luke's Mid America Heart Institute, Kansas City, Missouri, USA
| | - Kerstin Piayda
- CardioVascular Center Frankfurt, Frankfurt, Germany; Heinrich-Heine-University, Division of Cardiology, Pulmonology and Vascular Medicine, Düsseldorf, Germany
| | - Radoslaw Pracoń
- Coronary and Structural Heart Diseases Department, National Institute of Cardiology, Warsaw, Poland
| | | | - Eduardo Flores-Umanzor
- Department of Cardiology, Hospital Clinic of Barcelona, August Pi I Sunyer Biomedical Research Institute, University of Barcelona, Barcelona, Spain
| | - Laurent Faroux
- Quebec Heart and Lung Institute, Laval University, Quebec City, Quebec, Canada
| | - Kasper Korsholm
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | - Julian K R Chun
- Cardioangiologisches Centrum Bethanien, Medizinische Klinik III, Markuskrankenhaus, Frankfurt, Germany
| | - Shaojie Chen
- Cardioangiologisches Centrum Bethanien, Medizinische Klinik III, Markuskrankenhaus, Frankfurt, Germany
| | - Moniek Maarse
- Cardiology, St Antonius Hospital, Nieuwegein, the Netherlands; LB Amsterdam University Medical Center, Amsterdam, the Netherlands
| | - Kristi Montrella
- University of Pittsburgh Medical Center Heart and Vascular Institute, University of Pittsburgh, Altoona, Pennsylvania, USA
| | - Zakeih Chaker
- Division of Cardiology, West Virginia School of Medicine, Morgantown, West Virginia, USA
| | - Jocelyn N Spoon
- International Heart Institute of Montana, Missoula, Montana, USA
| | - Luigi E Pastormerlo
- Fondazione Toscana Gabriele Monasterio Massa, Scuola Superiore Sant'Anna, Pisa, Italy
| | | | | | - Carmen M Moldovan
- Division of Cardiology and Structural Heart Diseases, Medical University of Silesia, Katowice, Poland
| | - Mohammed Qintar
- Division of Cardiology, Henry Ford Health System, Detroit, Michigan, USA
| | - Mehmet K Aktas
- Division of Cardiology, University of Rochester Medical Center, Rochester, New York, USA
| | - Luca Branca
- Catheterization Laboratory, Cardiothoracic Department, Spedali Civili of Brescia, Brescia, Italy
| | - Andrea Radinovic
- Arrhythmology Department, San Raffaele University Hospital, Milan, Italy
| | - Pradhum Ram
- Emory University Hospital, Atlanta, Georgia, USA
| | - Rayan S El-Zein
- Division of Cardiology, OhioHealth Doctors Hospital/OhioHealth Riverside Methodist Hospital, Columbus, Ohio, USA
| | | | - Wern Yew Ding
- Liverpool Heart and Chest Hospital, Liverpool, United Kingdom
| | - Bassel Sayegh
- Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA; The Heart, Lung and Vascular Institute, Excela Health, Pittsburgh, Pennsylvania, USA
| | | | - Oh-Hyun Lee
- Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Solomon O Badejoko
- Division of Internal Medicine, St Joseph's Medical Center (Dignity Health), Stockton, California, USA
| | | | - Nabeela Karim
- Royal Brompton and Harefield Hospitals, Part of Guys' and St Thomas' National Health Service Foundation Trust, London, United Kingdom
| | - Ahmed M Zaghloul
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | | | - Rachel M Kaplan
- Northwestern University, Bluhm Cardiovascular Institute, Chicago, Illinois, USA
| | - Oluseun Alli
- Division of Cardiology, Novant Health Heart and Vascular Institute, Charlotte, North Carolina, USA
| | - Aamir Ahmed
- Rush University Medical Center, Chicago, Illinois, USA
| | | | - Bradley P Knight
- Northwestern University, Bluhm Cardiovascular Institute, Chicago, Illinois, USA
| | - Venkata M Alla
- Creighton University School of Medicine, Omaha, Nebraska, USA
| | - Sidakpal S Panaich
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Tom Wong
- Royal Brompton and Harefield Hospitals, Part of Guys' and St Thomas' National Health Service Foundation Trust, London, United Kingdom
| | | | - Rashaad Chothia
- Division of Internal Medicine, St Joseph's Medical Center (Dignity Health), Stockton, California, USA
| | - Jung-Sun Kim
- Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Seoul, Korea
| | | | - Raveen Bazaz
- Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Dhiraj Gupta
- Liverpool Heart and Chest Hospital, Liverpool, United Kingdom
| | | | - Carlos E Sanchez
- Division of Cardiology, OhioHealth Doctors Hospital/OhioHealth Riverside Methodist Hospital, Columbus, Ohio, USA
| | | | - Patrizio Mazzone
- Arrhythmology Department, San Raffaele University Hospital, Milan, Italy
| | - Marianna Adamo
- Catheterization Laboratory, Cardiothoracic Department, Spedali Civili of Brescia, Brescia, Italy
| | - Fred Ling
- Division of Cardiology, University of Rochester Medical Center, Rochester, New York, USA
| | - Dee Dee Wang
- Division of Cardiology, Henry Ford Health System, Detroit, Michigan, USA
| | - William O'Neill
- Division of Cardiology, Henry Ford Health System, Detroit, Michigan, USA
| | - Wojtek Wojakowski
- Division of Cardiology and Structural Heart Diseases, Medical University of Silesia, Katowice, Poland
| | | | - Sergio Berti
- Fondazione Toscana Gabriele Monasterio Massa, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Daniel Spoon
- International Heart Institute of Montana, Missoula, Montana, USA
| | - Akram Kawsara
- Division of Cardiology, West Virginia School of Medicine, Morgantown, West Virginia, USA
| | - George Jabbour
- University of Pittsburgh Medical Center Heart and Vascular Institute, University of Pittsburgh, Altoona, Pennsylvania, USA
| | - Lucas V A Boersma
- Cardiology, St Antonius Hospital, Nieuwegein, the Netherlands; LB Amsterdam University Medical Center, Amsterdam, the Netherlands
| | - Boris Schmidt
- Cardioangiologisches Centrum Bethanien, Medizinische Klinik III, Markuskrankenhaus, Frankfurt, Germany
| | | | - Josep Rodés-Cabau
- Quebec Heart and Lung Institute, Laval University, Quebec City, Quebec, Canada
| | - Xavier Freixa
- Department of Cardiology, Hospital Clinic of Barcelona, August Pi I Sunyer Biomedical Research Institute, University of Barcelona, Barcelona, Spain
| | | | - Laurent Fauchier
- Service de Cardiologie, Centre Hospitalier Universitaire Trousseau Faculté de Médecine, Université François Rabelais, Tours, France
| | - Marcin Demkow
- Coronary and Structural Heart Diseases Department, National Institute of Cardiology, Warsaw, Poland
| | | | - Michael L Main
- Division of Cardiology, Saint Luke's Mid America Heart Institute, Kansas City, Missouri, USA
| | - Benjamin Hibbert
- Capital Research Group, University of Ottawa Heart Institute, Ottawa, Ontario, Canada
| | - David R Holmes
- Department of Cardiovascular Diseases, Mayo Clinic School of Medicine, Rochester, Minnesota, USA
| | - Mohamad Alkhouli
- Department of Cardiovascular Diseases, Mayo Clinic School of Medicine, Rochester, Minnesota, USA.
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Karim N, Kozhuharov N, Jarman J, Furniss S, Veasey R, Ullah W, Vouliotis AI, Martin C, Kalla M, Osmanagic A, Ginks M, Pope M, Christian Sitcherling C, Gupta D, Wong T. Safety and acute clinical outcomes of atrial fibrillation catheter ablation in octogenarians: a multicentre evaluation with a matched younger cohort. Europace 2021. [DOI: 10.1093/europace/euab116.235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
OnBehalf
Sven Knecht and the International Octogenarian AF ablation group
Background
Octogenarians are a fast-growing demographic with a high burden of atrial fibrillation (AF). There are limited data on procedural safety and acute outcomes of catheter ablation (CA) for AF in this group.
Purpose
Investigation of complications & outcomes in octogenarians undergoing CA for AF.
Methods
Data on all octogenarian patients who underwent AF ablation at nine European cardiology centres between 2013 and 2019 were retrospectively analysed and matched with control patients aged <80 years. The characteristics used for matching were type of AF, type of procedure (de novo or redo), & the year of procedure.
Results
216 octogenarians (81.9 ± 1.9 years; 52.8% females) underwent an AF ablation procedure, and were matched with 216 patients aged <80 years (62.4 ± 9.5 years, 34.7% females), p <0.001 for both. The proportion of paroxysmal and persistent AF was 43.5% & 56.5% respectively in both groups, and 79.3% of the procedures were de novo. RF ablation made up 75.4% & 75.9% (p = 0.90) procedures in octogenarians and controls respectively. 17 complications occurred in 14 (7.9%) octogenarian patients and 11 in 11 (5.1%) patients in the younger matched cohort (p = 0.07). There were 4.2% & 1.9% major complications (p= 0.17) and 3.7% & 3.2% minor complications (p= 0.77) in the octogenarian & younger cohorts respectively. Complications in octogenarians consisted of groin complications (n = 6), pneumonia (n = 3), pericardial effusion (n = 2), phrenic nerve injury (n = 2), pulmonary oedema (n = 1), gastroparesis (n = 1), stroke (n = 1). Acute procedural success rates were 99.1% & 99.5% (p = 0.62) The complication rates were similar for RF; 6.0% vs 5.4% (p = 0.79) and Cryoballoon; 14.0% vs 4.1% (p = 0.09) in both octogenarians and younger cohort respectively.
Conclusion
In spite of significantly higher overall risk profile of octogenarians undergoing AF ablation, there is no difference in acute procedural success and complication rates as compared to younger patients Catheter ablation of AF in octogenerians Octogenarians n = 216 Matched Controls (aged < 80yrs) n = 216 P value Age (yrs), mean (SD)s 81.9 (1.9) 62.4(9.5) < 0.0001 Females, (%) 52.8 34.7 0.0002 CHA2DS2-VASc, mean (SD) 3.6 (1.2) 1.4 (1.3) < 0.0001 Mean LA size, mm 42.8 ± 8.3mm 45.8 ± 16.2 0.062 Impaired LV function, (%) 23.7 17.9 0.206 IHD, (%) 20.7 5.9 < 0.0001 Procedural time (mins), mean (sd) 150.6 (69.7) 148.9 (64.4) 0.914 All complications, n (%) 17 (7.9) 11 (5.1) 0.073
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Affiliation(s)
- N Karim
- Royal Brompton Hospital, London, United Kingdom of Great Britain & Northern Ireland
| | - N Kozhuharov
- Liverpool Heart and Chest Hospital, Liverpool, United Kingdom of Great Britain & Northern Ireland
| | - J Jarman
- Royal Brompton Hospital, London, United Kingdom of Great Britain & Northern Ireland
| | - S Furniss
- Eastbourne District General Hospital, Eastbourne, United Kingdom of Great Britain & Northern Ireland
| | - R Veasey
- Eastbourne District General Hospital, Eastbourne, United Kingdom of Great Britain & Northern Ireland
| | - W Ullah
- University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom of Great Britain & Northern Ireland
| | - A-I Vouliotis
- University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom of Great Britain & Northern Ireland
| | - C Martin
- Royal Papworth Hospital NHS Foundation Trust, Cambridge, United Kingdom of Great Britain & Northern Ireland
| | - M Kalla
- Queen Elizabeth Hospital Birmingham, Birmingham, United Kingdom of Great Britain & Northern Ireland
| | - A Osmanagic
- Queen Elizabeth Hospital Birmingham, Birmingham, United Kingdom of Great Britain & Northern Ireland
| | - M Ginks
- John Radcliffe Hospital, Oxford, United Kingdom of Great Britain & Northern Ireland
| | - M Pope
- John Radcliffe Hospital, Oxford, United Kingdom of Great Britain & Northern Ireland
| | | | - D Gupta
- Liverpool Heart and Chest Hospital, Liverpool, United Kingdom of Great Britain & Northern Ireland
| | - T Wong
- Royal Brompton Hospital, London, United Kingdom of Great Britain & Northern Ireland
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6
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Shi R, Chen Z, Pope MTB, Zaman JAB, Debney M, Marinelli A, Boyalla V, Sathishkumar A, Karim N, Cantor E, Valli H, Haldar S, Jones DG, Hussain W, Markides V, Betts TR, Wong T. Individualized ablation strategy to treat persistent atrial fibrillation: Core-to-boundary approach guided by charge-density mapping. Heart Rhythm 2021; 18:862-870. [PMID: 33610744 DOI: 10.1016/j.hrthm.2021.02.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [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: 11/01/2020] [Revised: 02/05/2021] [Accepted: 02/08/2021] [Indexed: 12/26/2022]
Abstract
BACKGROUND Noncontact charge-density mapping allows rapid real-time global mapping of atrial fibrillation (AF), offering the opportunity for a personalized ablation strategy. OBJECTIVE The purpose of this study was to compare the 2-year outcome of an individualized strategy consisting of pulmonary vein isolation (PVI) plus core-to-boundary ablation (targeting the conduction pattern core with an extension to the nearest nonconducting boundary) guided by charge-density mapping, with an empirical PVI plus posterior wall electrical isolation (PWI) strategy. METHODS Forty patients (age 62 ± 12 years; 29 male) with persistent AF (10 ± 5 months) prospectively underwent charge-density mapping-guided PVI, followed by core-to-boundary stepwise ablation until termination of AF or depletion of identified cores. Freedom from AF/atrial tachycardia (AT) at 24 months was compared with a propensity score-matched control group of 80 patients with empirical PVI + PWI guided by conventional contact mapping. RESULTS Acute AF termination occurred in 8 of 40 patients after charge-density mapping-guided PVI alone and in 21 of the remaining 32 patients after core-to-boundary ablation in the study cohort, compared with 8 of 80 (10%) in the control cohort (P <.001). On average, 2.2 ± 0.6 cores were ablated post-PVI before acute AF termination. At 24 months, freedom from AF/AT after a single procedure was 68% in the study group vs 46% in the control group (P = .043). CONCLUSION An individualized ablation strategy consisting of PVI plus core-to-boundary ablation guided by noncontact charge-density mapping is a feasible and effective strategy for treating persistent AF, with a favorable 24-month outcome.
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Affiliation(s)
- Rui Shi
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom
| | - Zhong Chen
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom
| | - Michael T B Pope
- Oxford Biomedical Research Centre, Oxford University Hospitals NHS Trust, Oxford, United Kingdom
| | - Junaid A B Zaman
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom
| | - Mike Debney
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom
| | - Alessio Marinelli
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom
| | - Vennela Boyalla
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom
| | - Anitha Sathishkumar
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom
| | - Nabeela Karim
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom
| | - Emily Cantor
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom
| | - Haseeb Valli
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom
| | - Shouvik Haldar
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom
| | - David G Jones
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom
| | - Wajid Hussain
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom
| | - Vias Markides
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom
| | - Timothy R Betts
- Oxford Biomedical Research Centre, Oxford University Hospitals NHS Trust, Oxford, United Kingdom
| | - Tom Wong
- Heart Rhythm Centre, Royal Brompton and Harefield Hospitals, Part of Guys & St Thomas NHS Foundation Trust, London, United Kingdom.
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Ma Y, Zaman JAB, Shi R, Karim N, Panikker S, Chen Z, Chen W, Jones DG, Hussain W, Markides V, Wong T. Spectral characterization and impact of stepwise ablation protocol including LAA electrical isolation on persistent AF. Pacing Clin Electrophysiol 2020; 44:318-326. [PMID: 33377500 DOI: 10.1111/pace.14151] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 12/04/2020] [Accepted: 12/13/2020] [Indexed: 12/14/2022]
Abstract
OBJECTIVES To study how left atrial appendage electrical isolation (LAAEI) impacts atrial dominant frequency (DF) in patients with long-standing persistent atrial fibrillation (LSPAF). BACKGROUND LAAEI is associated with a high probability of freedom from atrial fibrillation (AF) and spectral analysis may identify high-frequency sources. How LAAEI impacts the AF dynamics and the subgroup of LSPAF patients in whom LAAEI would be most beneficial, is unclear. METHODS Twenty patients with LSPAF were included in the study. Fast Fourier transforms (FFT) were performed on atrial electrograms recorded from 13 sites in the LA and RA. The highest peak frequency was defined as DF. RESULTS There was no significant difference in DF between atrial sites except for at the superior vena cava which had the lowest DF at baseline. Stepwise ablation consisting of circumferential pulmonary vein isolation and a linear ablation set of mitral isthmus and roof significantly reduced the DF within the coronary sinus (CS) (5.93 ± 0.98 Hz vs. 5.09 ± 0.72 Hz, p < .05) and the LA posterior wall (LApos) (6.26 ± 0.92 Hz vs. 5.43 ± 0.98 Hz, p < .01). LAAEI preferentially further decreased the DF at the LApos (p < .01), but not at the CS. In cases where there was < 13.6% reduction in the DF of the LApos following the stepwise ablation, the addition of LAAEI was associated with an increased restoration of sinus rhythm (55%, p < .05). CONCLUSION LAAEI in addition to stepwise ablation results in further reduction of the DF in the LApos, which is associated with acute termination of AF and favorable ablation outcome.
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Affiliation(s)
- Yuedong Ma
- Heart Rhythm Centre, The Royal Brompton and Harefield NHS Foundation Trust, National Heart and Lung Institute, Imperial College London, London, UK.,Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Junaid A B Zaman
- Heart Rhythm Centre, The Royal Brompton and Harefield NHS Foundation Trust, National Heart and Lung Institute, Imperial College London, London, UK
| | - Rui Shi
- Heart Rhythm Centre, The Royal Brompton and Harefield NHS Foundation Trust, National Heart and Lung Institute, Imperial College London, London, UK.,Department of Cardiology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Nabeela Karim
- Heart Rhythm Centre, The Royal Brompton and Harefield NHS Foundation Trust, National Heart and Lung Institute, Imperial College London, London, UK
| | - Sandeep Panikker
- Heart Rhythm Centre, The Royal Brompton and Harefield NHS Foundation Trust, National Heart and Lung Institute, Imperial College London, London, UK
| | - Zhong Chen
- Heart Rhythm Centre, The Royal Brompton and Harefield NHS Foundation Trust, National Heart and Lung Institute, Imperial College London, London, UK
| | - Wen Chen
- Department of Medical Statistics, School of Public Health, Sun Yat-Sen University, Guangzhou, China
| | - David Gareth Jones
- Heart Rhythm Centre, The Royal Brompton and Harefield NHS Foundation Trust, National Heart and Lung Institute, Imperial College London, London, UK
| | - Wajid Hussain
- Heart Rhythm Centre, The Royal Brompton and Harefield NHS Foundation Trust, National Heart and Lung Institute, Imperial College London, London, UK
| | - Vias Markides
- Heart Rhythm Centre, The Royal Brompton and Harefield NHS Foundation Trust, National Heart and Lung Institute, Imperial College London, London, UK
| | - Tom Wong
- Heart Rhythm Centre, The Royal Brompton and Harefield NHS Foundation Trust, National Heart and Lung Institute, Imperial College London, London, UK
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8
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Karim N, Ho SY, Nicol E, Li W, Zemrak F, Markides V, Reddy V, Wong T. The left atrial appendage in humans: structure, physiology, and pathogenesis. Europace 2019; 22:5-18. [DOI: 10.1093/europace/euz212] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 07/12/2019] [Indexed: 01/01/2023] Open
Abstract
Abstract
For many years, the left atrial appendage (LAA) was considered a dormant embryological remnant; however, it is a structurally complex and functional organ that contributes to cardiac haemodynamic changes and volume homeostasis through both its contractile properties and neurohormonal peptide secretion. When dysfunctional, the LAA contributes to thrombogenesis and subsequent increased predisposition to cardioembolic events. Consequently, the LAA has gained much attention as a therapeutic target to lower this risk. In addition, attention has focused on the LAA in its role as an electrical trigger for atrial tachycardia and atrial fibrillation with ablation of the LAA to achieve electrical isolation showing promising results in the maintenance of sinus rhythm. This in-depth review explores the structure, physiology and pathophysiology of the LAA, as well as LAA intervention and their sequelae.
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Affiliation(s)
- Nabeela Karim
- Department of Cardiology, The Royal Brompton and Harefield NHS Foundation Trust, Imperial College London, Sydney Street, London, UK
| | - Siew Yen Ho
- Department of Cardiology, The Royal Brompton and Harefield NHS Foundation Trust, Imperial College London, Sydney Street, London, UK
| | - Edward Nicol
- Department of Cardiology, The Royal Brompton and Harefield NHS Foundation Trust, Imperial College London, Sydney Street, London, UK
| | - Wei Li
- Department of Cardiology, The Royal Brompton and Harefield NHS Foundation Trust, Imperial College London, Sydney Street, London, UK
| | - Filip Zemrak
- Barts Heart Centre, St. Bartholomew’s Hospital, Barts Health NHS Trust, London, UK
| | - Vias Markides
- Department of Cardiology, The Royal Brompton and Harefield NHS Foundation Trust, Imperial College London, Sydney Street, London, UK
| | - Vivek Reddy
- Helmsley Centre for Cardiac Electrophysiology, Mount Sinai Hospital, New York City, NY, USA
| | - Tom Wong
- Department of Cardiology, The Royal Brompton and Harefield NHS Foundation Trust, Imperial College London, Sydney Street, London, UK
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9
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Karim N, Marinelli A, Cantor E, Boyalla V, Malaczynska-Rajpold K, Ahmed O, Khan H, Haldar S, Jones D, Hussein W, Markides V, Wong T, Jarman J. P2831Safety of atrial fibrillation catheter ablation in the elderly. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.1141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Catheter ablation for drug refractory, symptomatic atrial fibrillation (AF), is becoming increasingly common and can be beneficial in alleviating symptoms. However, in the elderly, there are concerns about the risks an invasive procedure poses, with limited published data available in those aged over 80 years.
Purpose
To determine the complication risk of AF catheter ablation in the elderly
Methods
Complications were identified from patient records in 3156 consecutive patients who underwent radiofrequency catheter ablation for AF, at a tertiary cardiology centre between 2013–2017. All cases were performed under general anesthesia.
Results
In this cohort of 3156 patients (mean age= 62.9±11.0 years, female = 29.9%), 90 (2.85%) (mean age= 66±10.0 years, female = 49.5%) complications were identified. In patients aged ≥80 years, complications occurred in 5 out of 99 patients (5.05%) (mean age= 82.6±1.2, female=100%), compared to 85 out of 3057 patients (2.78%) in those aged <80 years (mean age= 65±10.3, female = 49.4%). The difference was not significant p=0.18. Complications in the elderly all occurred acutely, and included groin haematoma (2.02%), pneumonia (2.02%) and pericardial effusion (1.01%).
Conclusion
Catheter ablation for AF in patients ≥80 years of age, is not associated with a significant increase in complication risk, compared to those who are younger.
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Affiliation(s)
- N Karim
- Royal Brompton Hospital, London, United Kingdom
| | - A Marinelli
- Royal Brompton Hospital, London, United Kingdom
| | - E Cantor
- Royal Brompton Hospital, London, United Kingdom
| | - V Boyalla
- Royal Brompton Hospital, London, United Kingdom
| | | | - O Ahmed
- Royal Brompton Hospital, London, United Kingdom
| | - H Khan
- Royal Brompton Hospital, London, United Kingdom
| | - S Haldar
- Royal Brompton Hospital, London, United Kingdom
| | - D Jones
- Royal Brompton Hospital, London, United Kingdom
| | - W Hussein
- Royal Brompton Hospital, London, United Kingdom
| | - V Markides
- Royal Brompton Hospital, London, United Kingdom
| | - T Wong
- Royal Brompton Hospital, London, United Kingdom
| | - J Jarman
- Royal Brompton Hospital, London, United Kingdom
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10
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Amin T, Karim N, Roberts M, McMahon L. SAT-058 Signal-averaged ECG abnormality and mortality in hemodialysis patients: A prospective study. Kidney Int Rep 2019. [DOI: 10.1016/j.ekir.2019.05.082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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12
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Karim N, Pathrose J, Fathallah H, El Desouki I, Perry A, Starnes S, Morris J. P2.01-129 Potential Impact of KRAS Molecular Profiling of Non-Squamous Non-Small Cell Lung Cancer (NSCLC). J Thorac Oncol 2018. [DOI: 10.1016/j.jtho.2018.08.1184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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13
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Creta A, Providencia R, Karim N, Papageorgiou N, Sporton S, Chow A, Finlay M, Ahsan S, Earley MJ, Khan F, Hunter R, Lowe M, Segal O, Lambiase PD, Schilling RJ. P5773Atrial fibrillation catheter ablation in patients with hypertrophic cardiomyopathy: multi-centre experience and application of HCM-Risk SCD score to predict ablation outcome. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy566.p5773] [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: 11/12/2022] Open
Affiliation(s)
- A Creta
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - R Providencia
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - N Karim
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - N Papageorgiou
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - S Sporton
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - A Chow
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - M Finlay
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - S Ahsan
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - M J Earley
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - F Khan
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - R Hunter
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - M Lowe
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - O Segal
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - P D Lambiase
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - R J Schilling
- Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
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Karim N, Murtaza G, Naeem M. Whole‐exome sequencing identified a novel frameshift mutation in
SDR9C7
underlying autosomal recessive congenital ichthyosis in a Pakistani family. Br J Dermatol 2017; 177:e191-e192. [DOI: 10.1111/bjd.15535] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- N. Karim
- Medical Genetics Research Laboratory Department of Biotechnology Quaid‐I‐Azam University Islamabad Pakistan
| | - G. Murtaza
- Medical Genetics Research Laboratory Department of Biotechnology Quaid‐I‐Azam University Islamabad Pakistan
| | - M. Naeem
- Medical Genetics Research Laboratory Department of Biotechnology Quaid‐I‐Azam University Islamabad Pakistan
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Adlakha R, Obiechina N, Gill A, Brice H, Parwes I, Barnes A, Davies A, Diamanto A, Karim N, Hawkins L, Michael A, Nandi A. 126Implantable loop recorders - diagnostic yield in patients with syncope and presyncope. Europace 2017. [DOI: 10.1093/europace/eux283.119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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16
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Providencia R, Srinivasan N, Karim N, Honarbakhsh S, Ferreira MJ, Goncalves L, Marijon E, Lambiase P. 93Impact of QTc formulae in the prevalence of short and long corrected QT intervals in a young adult cohort. Europace 2017. [DOI: 10.1093/europace/eux283.088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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17
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Karim N, Jacob A, Shaukat M, Hua Y, Chiu H, Mehta A, Moore P, Chow A. 59Can high volume tertiary centres with 24/7 device implanting service provide improved efficacy and outcomes compared to a large district general hospital model? Europace 2017. [DOI: 10.1093/europace/eux283.054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Aluisio A, Mbanjumucyo G, Barry M, Karim N, Levine A. 193 Impact of Implementation of Emergency Medicine Training on Emergency Department Mortality in Kigali, Rwanda: An Interrupted Time-Series Quasi-Experimental Design. Ann Emerg Med 2017. [DOI: 10.1016/j.annemergmed.2017.07.220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Karim N, Aral M, Eduwor S, Wald D, Finlay M. 46Smartphone apps for the detection of AF. Europace 2017. [DOI: 10.1093/europace/eux283.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Providência R, Karim N, Srinivasan N, Honarbakhsh S, Vidigal Ferreira MJ, Gonçalves L, Marijon E, Lambiase PD. Impact of QTc formulae in the prevalence of short corrected QT interval and impact on probability and diagnosis of short QT syndrome. Heart 2017; 104:502-508. [DOI: 10.1136/heartjnl-2017-311673] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 07/26/2017] [Accepted: 08/05/2017] [Indexed: 11/03/2022] Open
Abstract
ObjectiveTo assess the prevalence of short corrected QT (QTc) intervals and its impact on short QT syndrome (SQTS) diagnosis using different QT correction formulae.MethodsObservational study. The prevalence of short QTc intervals was estimated using four different QT correction formulae in 14 662 young adults from the ‘Sudden Cardiac Death Screening of Risk FactOrS’ (SCD-SOS) cohort. Then, using data from this cohort and the pooled-cohort analysed by Gollob et al, comprising 61 patients with SQTS, we assessed the impact of the different QTc correction formulae on SQTS probability and diagnosis based on the Expert Consensus recommendations (QTc ≤330 ms or QTc 330–360 ms+1 additional risk feature).ResultsThe prevalence of individuals with a QTc ≤330 and ≤320 ms in the SCD-SOS cohort was extremely low (≤0.07% and≤0.02%, respectively), and these were more frequently identified by the Framingham correction. The different QTc correction formulae led to a shift in SQTS probability in 5%–10% of individuals in both the SCD-SOS and Gollob cohort). Intermediate probability individuals were rare (<0.1%), and no high-SQTS probability individuals were identified in the SCD-SOS cohort. Based on Consensus criteria, instead of 12 (0.08%) individuals being diagnosed with SQTS using the Bazett equation, a different number of individuals would meet diagnostic criteria with the other formulae: 11 (0.08%) using Fridericia, 9 (0.06%) with Hodges and 16 (0.11%) using the Framingham equation.ConclusionPrevalence of SQTS in the apparently healthy adult population is low. Applying different QTc correction formulae leads to significant reclassification of SQTS probability and their impact on predicting outcomes should be assessed.
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Providencia R, Srinivasan N, Karim N, Honarbakhsh S, Ferreira MJ, Goncalves L, Lambiase PD. P1793Impact of QTc formulae in the prevalence of long corrected QT interval and impact on risk of Long QT Syndrome. Europace 2017. [DOI: 10.1093/ehjci/eux161.102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Furniss G, Opel A, Hussein A, Pearman C, Grace A, Connelly D, Orlowski A, Banerjee A, McNicholas T, Providencia R, Montañes M, Providencia R, Panagopoulos D, Tomlinson D, Dalrymple-Hay M, Haywood G, Butler A, Ang R, Ullah W, Schwartz R, Fannon M, Finlay M, Hunter R, Schilling R, Das M, Asfour I, Morgan M, Ronayne C, Shaw M, Snowdon R, Gupta D, Todd D, King R, Hall M, Modi S, Mediratta N, Gupta D, Reddy V, Neuzil P, Willems S, Verma A, Heck P, Schilling R, Lambiase P, Hall M, Nicholl B, McQueenie R, Jani BD, McKeag N, Gallacher K, Mair F, Heaton D, Macdonald J, Burnell J, Ryan R, Marshall T, Sutton C, O'Callaghan S, Kenny R, Karim N, Srinivasan N, Ferreira M, Goncalves L, Lambiase P, Toledano M, Field E, Walsh H, Maguire K, Cervi E, Kaski J, Perez Tome M, Pantazis A, Elliott P, Lambiase P, Segal O. ORAL ABSTRACTS (3)EP & Ablation31LEFT ATRIAL POSTERIOR WALL ISOLATION (THE “BOX LESION PATTERN”) IN THE TREATMENT OF ATRIAL FIBRILLATION: A SINGLE CENTRE EXPERIENCE32DAY CASE CRYOBLATION (CRYO) FOR PAROXYSMAL ATRIAL FIBRILLATION (pAF) IN THE DISTRICT GENERAL HOSPITAL IS SAFE AND EFFECTIVE IF DONE IN HIGH VOLUME WITH EXPERIENCED OPERATORS33ABLATION INDEX-GUIDED PULMONARY VEIN ISOLATION FOR ATRIAL FIBRILLATION MAY IMPROVE CLINICAL OUTCOMES IN COMPARISON TO CONTACT FORCE-GUIDED ABLATION34THE PROCEDURAL COMPLICATION RATES AND SHORT-TERM SUCCESS RATES OF THORACOSCOPIC AF ABLATION DURING THE INSTITUTIONAL LEARNING CURVE35INITIAL PROCEDURAL RESULTS FROM DDRAMATIC-SVT STUDY: DD MECHANISM IDENTIFICATION AND LOCALISATION USING DIPOLE DENSITY MAPPING TO GUIDE ABLATION STRATEGY36MORBIDITY AND MORTALITY IN MIDDLE-AGED INDIVIDUALS WITH ATRIAL FIBRILLATION: UK BIOBANK DATAClinical EP37THE GM AHSN AF LANDSCAPE TOOL: A SHARED PUBLIC DATA PLATFORM TO PROMOTE QUALITY IMPROVEMENTS AND IDENTIFY OPPORTUNITIES TO PREVENT AF-RELATED STROKE IN THE DEVOLVED GREATER MANCHESTER HEALTH SYSTEM38REAL WORLD PERSISTENCE, ADHERENCE AND SWITCH-OVER ACROSS ANTICOAGULANTS IN ATRIAL FIBRILLATION-A NATIONAL POPULATION-BASED STUDY39ORTHOSTATIC HYPOTENSION AND ATRIAL FIBRILLATION40PREVALENCE OF SHORT QT AND CRITERIA OF SEVERITY IN A YOUNG ASYMPTOMATIC COHORT41SURFACE ELECTROCARDIOGRAPHIC FEATURES AND PREVALENCE OF ARRHYTHMIAS IN PAEDIATRIC FRIEDREICH'S ATAXIA42RISK STRATIFICATION OF TYPE 1 MYOTONIC DYSTROPHY: IS THE ECG ACCURATE ENOUGH TO SELECT PATIENTS AT RISK OF BRADYARRHYTHMIC EVENTS? Europace 2016. [DOI: 10.1093/europace/euw272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Nairismägi ML, Tan J, Lim JQ, Nagarajan S, Ng CCY, Rajasegaran V, Huang D, Lim WK, Laurensia Y, Wijaya GC, Li ZM, Cutcutache I, Pang WL, Thangaraju S, Ha J, Khoo LP, Chin ST, Dey S, Poore G, Tan LHC, Koh HKM, Sabai K, Rao HL, Chuah KL, Ho YH, Ng SB, Chuang SS, Zhang F, Liu YH, Pongpruttipan T, Ko YH, Cheah PL, Karim N, Chng WJ, Tang T, Tao M, Tay K, Farid M, Quek R, Rozen SG, Tan P, Teh BT, Lim ST, Tan SY, Ong CK. JAK-STAT and G-protein-coupled receptor signaling pathways are frequently altered in epitheliotropic intestinal T-cell lymphoma. Leukemia 2016; 30:1311-9. [PMID: 26854024 PMCID: PMC4895162 DOI: 10.1038/leu.2016.13] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [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: 07/15/2015] [Revised: 01/07/2016] [Accepted: 01/18/2016] [Indexed: 12/11/2022]
Abstract
Epitheliotropic intestinal T-cell lymphoma (EITL, also known as type II enteropathy-associated T-cell lymphoma) is an aggressive intestinal disease with poor prognosis and its molecular alterations have not been comprehensively characterized. We aimed to identify actionable easy-to-screen alterations that would allow better diagnostics and/or treatment of this deadly disease. By performing whole-exome sequencing of four EITL tumor-normal pairs, followed by amplicon deep sequencing of 42 tumor samples, frequent alterations of the JAK-STAT and G-protein-coupled receptor (GPCR) signaling pathways were discovered in a large portion of samples. Specifically, STAT5B was mutated in a remarkable 63% of cases, JAK3 in 35% and GNAI2 in 24%, with the majority occurring at known activating hotspots in key functional domains. Moreover, STAT5B locus carried copy-neutral loss of heterozygosity resulting in the duplication of the mutant copy, suggesting the importance of mutant STAT5B dosage for the development of EITL. Dysregulation of the JAK-STAT and GPCR pathways was also supported by gene expression profiling and further verified in patient tumor samples. In vitro overexpression of GNAI2 mutants led to the upregulation of pERK1/2, a member of MEK-ERK pathway. Notably, inhibitors of both JAK-STAT and MEK-ERK pathways effectively reduced viability of patient-derived primary EITL cells, indicating potential therapeutic strategies for this neoplasm with no effective treatment currently available.
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Affiliation(s)
- M-L Nairismägi
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - J Tan
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore.,Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - J Q Lim
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - S Nagarajan
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - C C Y Ng
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - V Rajasegaran
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - D Huang
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - W K Lim
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - Y Laurensia
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - G C Wijaya
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - Z M Li
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - I Cutcutache
- Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore.,Centre for Computational Biology, Duke-NUS Medical School, Singapore, Singapore
| | - W L Pang
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - S Thangaraju
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - J Ha
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - L P Khoo
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - S T Chin
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - S Dey
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - G Poore
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - L H C Tan
- Department of Pathology, Singapore General Hospital, Singapore, Singapore
| | - H K M Koh
- Advanced Molecular Pathology Laboratory, Singapore Health Services, Singapore, Singapore
| | - K Sabai
- Advanced Molecular Pathology Laboratory, Singapore Health Services, Singapore, Singapore
| | - H-L Rao
- Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - K L Chuah
- Department of Pathology, Tan Tock Seng Hospital, Singapore, Singapore
| | - Y-H Ho
- Department of Pathology, Tan Tock Seng Hospital, Singapore, Singapore
| | - S-B Ng
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore.,Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Department of Pathology, National University Hospital, National University Health System, Singapore, Singapore
| | - S-S Chuang
- Department of Pathology, Chi Mei Medical Center, Tainan, Taiwan.,Department of Pathology, Taipei Medical University and National Taiwan University, Taipei, Taiwan
| | - F Zhang
- Department of Pathology, Guangdong General Hospital, Guangzhou, China
| | - Y-H Liu
- Department of Pathology, Guangdong General Hospital, Guangzhou, China
| | - T Pongpruttipan
- Department of Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Y H Ko
- Department of Pathology, Samsung Medical Centre, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - P-L Cheah
- Department of Pathology, University of Malaya, Kuala Lumpur, Malaysia
| | - N Karim
- Department of Pathology, Hospital Raja Permaisuri Bainun, Ipoh, Malaysia
| | - W-J Chng
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore.,Department of Haematology-Oncology, National University Hospital, National University Health System, Singapore, Singapore
| | - T Tang
- Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - M Tao
- Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - K Tay
- Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - M Farid
- Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - R Quek
- Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - S G Rozen
- Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore.,Centre for Computational Biology, Duke-NUS Medical School, Singapore, Singapore
| | - P Tan
- Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore.,Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore.,Genome Institute of Singapore, A*STAR, Singapore, Singapore
| | - B T Teh
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore.,Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore.,Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore
| | - S T Lim
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore.,Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore.,Office of Education, Duke-NUS Medical School, Singapore, Singapore
| | - S-Y Tan
- Department of Pathology, Singapore General Hospital, Singapore, Singapore.,Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Department of Pathology, National University Hospital, National University Health System, Singapore, Singapore.,Department of Pathology, Guangdong General Hospital, Guangzhou, China.,Department of Pathology, University of Malaya, Kuala Lumpur, Malaysia.,Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore
| | - C K Ong
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
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Tanvir EM, Afroz R, Chowdhury M, Gan SH, Karim N, Islam MN, Khalil MI. A model of chlorpyrifos distribution and its biochemical effects on the liver and kidneys of rats. Hum Exp Toxicol 2015; 35:991-1004. [PMID: 26519480 DOI: 10.1177/0960327115614384] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This study investigated the main target sites of chlorpyrifos (CPF), its effect on biochemical indices, and the pathological changes observed in rat liver and kidney function using gas chromatography/mass spectrometry. Adult female Wistar rats (n = 12) were randomly assigned into two groups (one control and one test group; n = 6 each). The test group received CPF via oral gavage for 21 days at 5 mg/kg daily. The distribution of CPF was determined in various organs (liver, brain, heart, lung, kidney, ovary, adipose tissue, and skeletal muscle), urine and stool samples using GCMS. Approximately 6.18% of CPF was distributed in the body tissues, and the highest CPF concentration (3.80%) was found in adipose tissue. CPF also accumulated in the liver (0.29%), brain (0.22%), kidney (0.10%), and ovary (0.03%). Approximately 83.60% of CPF was detected in the urine. CPF exposure resulted in a significant increase in plasma transaminases, alkaline phosphatase, and total bilirubin levels, a significant reduction in total protein levels and an altered lipid profile. Oxidative stress due to CPF administration was also evidenced by a significant increase in liver malondialdehyde levels. The detrimental effects of CPF on kidney function consisted of a significant increase in plasma urea and creatinine levels. Liver and kidney histology confirmed the observed biochemical changes. In conclusion, CPF bioaccumulates over time and exerts toxic effects on animals.
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Affiliation(s)
- E M Tanvir
- Laboratory of Preventive and Integrative Biomedicine, Department of Biochemistry and Molecular Biology, Jahangirnagar University, Savar, Bangladesh Agrochemicals and Environmental Research Division, Institute of Food and Radiation Biology, Atomic Energy Research Establishment, Savar, Bangladesh Department of Biochemistry, Gono Bishwabidyalay, Mirzanagar, Savar, Bangladesh
| | - R Afroz
- Laboratory of Preventive and Integrative Biomedicine, Department of Biochemistry and Molecular Biology, Jahangirnagar University, Savar, Bangladesh
| | - Maz Chowdhury
- Agrochemicals and Environmental Research Division, Institute of Food and Radiation Biology, Atomic Energy Research Establishment, Savar, Bangladesh
| | - S H Gan
- Human Genome Centre, School of Medical Sciences, Universiti Sains Malaysia, Kelantan, Malaysia
| | - N Karim
- Laboratory of Preventive and Integrative Biomedicine, Department of Biochemistry and Molecular Biology, Jahangirnagar University, Savar, Bangladesh
| | - M N Islam
- Agrochemicals and Environmental Research Division, Institute of Food and Radiation Biology, Atomic Energy Research Establishment, Savar, Bangladesh
| | - M I Khalil
- Laboratory of Preventive and Integrative Biomedicine, Department of Biochemistry and Molecular Biology, Jahangirnagar University, Savar, Bangladesh Human Genome Centre, School of Medical Sciences, Universiti Sains Malaysia, Kelantan, Malaysia
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Ratnasingam J, Karim N, Paramasivam SS, Ibrahim L, Lim LL, Tan ATB, Vethakkan SR, Jalaludin A, Chan SP. Hypothalamic pituitary dysfunction amongst nasopharyngeal cancer survivors. Pituitary 2015; 18:448-55. [PMID: 25134488 DOI: 10.1007/s11102-014-0593-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [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: 10/24/2022]
Abstract
PURPOSE Radiation fields for nasopharyngeal cancer (NPC) include the base of skull, which places the hypothalamus and pituitary at risk of damage. We aimed to establish the prevalence, pattern and severity of hypothalamic pituitary (HP) dysfunction amongst NPC survivors. METHODS We studied 50 patients (31 males) with mean age 57 ± 12.2 years who had treatment for NPC between 3 and 21 years (median 8 years) without pre-existing HP disorder from other causes. All patients had a baseline cortisol, fT4, TSH, LH, FSH, oestradiol/testosterone, prolactin and renal function. All patients underwent dynamic testing with insulin tolerance test to assess the somatotroph and corticotroph axes. Baseline blood measurements were used to assess thyrotroph, gonadotroph and lactotroph function. RESULTS Hypopituitarism was present in 82% of patients, 30% single axis, 28% two axes, 18% three axes and 6% four axes deficiencies. Somatotroph deficiency was most common (78%) while corticotroph, gonadotroph and thyrotroph deficiencies were noted in 40% (4 complete/16 partial), 22 and 4% of the patients respectively. Hyperprolactinaemia was present in 30% of patients. The development of HP dysfunction was significantly associated with the time elapsed from irradiation, OR 2.5 (1.2, 5.3), p = 0.02, for every 2 years post treatment. The use of concurrent chemo-irradiation (CCRT) compared to those who had radiotherapy alone was also significantly associated with HP dysfunction, OR 14.5 (2.4, 87.7), p < 0.01. CONCLUSION Despite low awareness and detection rates, HP dysfunction post-NPC irradiation is common. Use of CCRT may augment time related pituitary damage. As these endocrinopathies result in significant morbidity and mortality we recommend periodic assessment of pituitary function amongst NPC survivors.
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Affiliation(s)
- J Ratnasingam
- Endocrine Unit, Department of Medicine, University Malaya Medical Centre, Kuala Lumpur, Malaysia,
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Neil E, Majd N, Morris J, Karim N, Molano J, Colapietro P, Curry R. ED-22 * CONCURRENCE OF GLIOMAS IN PATIENTS WITH MULTIPLE SCLEROSIS: CASE REPORT AND LITERATURE REVIEW. Neuro Oncol 2014. [DOI: 10.1093/neuonc/nou253.22] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Cardoso JC, Cokelaere K, Maertens M, Karim N, Jong TJ, Calonje E. When nonspecific histology can be a clue to the diagnosis: three cases of trigeminal trophic syndrome. Clin Exp Dermatol 2014; 39:596-9. [PMID: 24890685 DOI: 10.1111/ced.12332] [Citation(s) in RCA: 6] [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] [Subscribe] [Scholar Register] [Accepted: 01/05/2014] [Indexed: 11/26/2022]
Abstract
Trigeminal trophic syndrome (TTS) is a rare cause of facial ulceration, which is usually associated with damage to the trigeminal nerve pathway, either centrally or peripherally, the most common causes being cerebrovascular accidents and trigeminal nerve ablation procedures. We present three cases of TTS, emphasizing the histopathological features. All three patients presented with facial ulceration. Two patients had a single lesion, and the third had several ulcers. However, in all cases, there was involvement of the nasal ala, and the lesions were strictly unilateral. Histology consistently showed ulceration with signs of severe chronic trauma: scarring, lichenification and/or pseudoepitheliomatous hyperplasia. Diagnosis of TTS can be difficult, and requires close clinicopathological correlation. Histology is important in excluding the majority of possible conditions included in the differential diagnosis, mainly malignancy and infectious processes. Several treatments have been described, but TTS is frequently refractory to treatment.
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Affiliation(s)
- J C Cardoso
- Dermatology Department, University Hospital of Coimbra, Coimbra, Portugal
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Selim S, Rahman R, Yasmin R, Karim N, Chowdhury SH, Lona H, Nabi SG, Shafi T. Risk factors of acute coronary syndrome among Bangladeshi people. Mymensingh Med J 2013; 22:513-521. [PMID: 23982542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Two hundred consecutive patients of acute coronary syndrome aged 30-80 years (inclusive) admitted to the coronary care unit of National institute of Cardiovascular Diseases, Dhaka, were prospectively recruited as cases. Two hundred controls were prospectively selected either from individuals attending in the Shaheed Suhrawardy Medical College Hospital, admitted for elective surgery or in medicine ward for conditions that were unlikely to confound a comparative analysis. The Cases had significantly lower yearly incomes than controls, and significantly higher number of cases is occupied as sedentary worker. Smoking was an important risk factor. About 70% of cases and 45% of controls smoked previously cigarettes. Consumption of non smoke tobacco is another risk factor. The high risk of IHD in developing countries attributed to low consumption of fruit and vegetables, and in our study regular consumption of fruits (taking fruit at least 4 days a week) shows 20.5% cases and 33% of controls (OR 0.524, 95%CI 0.333-0.823) and p value was 0.005. Around 23.5% of the cases were diabetic compared with 4.5% of controls. We found 5% cases and 1.5% controls having known dyslipidemia. Although the body-mass index of cases was 24.68±3.06 Kg/M² and controls 20.54±4.37 Kg/M². The WHR was also significantly greater in cases 0.98±0.05M vs. controls 0.93±0.102M (p<0.001). About 31% of cases and 2% of controls had past history of myocardial infarction. The most predictive independent variables were previous smoking (p<0.001), WHR (p<0.001), history of hypertension (p<0.001), and income (p<0.001). Smoking and WHR were associated with the highest risks. The variables revealed to be significantly associated with acute coronary syndrome by bivariate analyses were all entered into the model directly. Eleven variables entered into the model. Of them Age, occupation, family income (yearly), fruit consumption, known hypertension, known DM, known dyslipidemia, previous MI, previous smoking, BMI and Waist and hip ratio were found to be the independent predictors of acute coronary syndrome. The study found that smoking tobacco, diabetes mellitus, hypertension, visceral obesity and less fruit intake are the important factors of acute coronary syndrome in Bangladesh.
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Affiliation(s)
- S Selim
- Dr Shahjada Selim, Department of Endocrinology & Metabolism, BIRDEM, Dhaka, Bangladesh
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Strom TA, Arora A, Osborn B, Karim N, Komabayashi T, Liu X. Endodontic release system for apexification with calcium hydroxide microspheres. J Dent Res 2012; 91:1055-9. [PMID: 22914537 DOI: 10.1177/0022034512459054] [Citation(s) in RCA: 10] [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] [Indexed: 11/17/2022] Open
Abstract
The use of calcium hydroxide (CH) as an intracanal medicament for apexification is widespread. However, because of a short residence time in the root canal, the CH must be refreshed frequently, increasing the number of appointments required and leading to patient non-compliance. We hypothesized that a core-/shell-structured CH microsphere system would lead to sustained slow release of calcium and hydroxide ions of CH for long periods of time, eliminating the need for multiple visits for apexification. In this study, calcium hydroxide microspheres (CHMSs) with a core/shell structure were prepared by an emulsion method. The CHMS shell was composed of alginate, which was crosslinked by the Ca(2+) released from the CH in the CHMSs. Therefore, this system provides a unique feedback loop that controls the release of ions from the CHMSs. The in vitro experiments from the root canals of extracted human teeth showed that the CHMSs had a sustained, slow release of Ca(2+), at a constant rate of approximately 2 to 3% per month from day one to the six-month endpoint of the experiment. After 6 months, 72.1 ± 5.8% of the total CH from the CHMSs remained in the root canals of the teeth, while only 46.9 ± 10.9% and 36.8 ± 7.5% remained from a commercial product (UltraCal(®)XS) and CH powder alone, respectively (p < 0.01). The pH of all of the formulations (CHMS, UltraCal(®) XS, and CH powder) in the extracted teeth never rose above 9 during the release period, indicating a buffering effect of the teeth. The core-/shell-structured CHMSs are, therefore, a promising delivery vehicle for the sustained slow release of Ca(2+) and OH(-) in the root canal.
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Affiliation(s)
- T A Strom
- Texas A&M Health Science Center, Baylor College of Dentistry, Dallas, TX 75246, USA
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Htwe TT, Karim N, Lam AK. Follicular thyroid carcinoma with insular component: a retrospective case study, immunohistochemical analysis and literature review. Singapore Med J 2012; 53:e49-e51. [PMID: 22434304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
This is a retrospective case study of a 61-year-old woman diagnosed with follicular thyroid carcinoma. The patient underwent thyroidectomy for the treatment of goitre after being admitted for shortness of breath. Microscopic and immunohistochemical studies were performed, which confirmed follicular carcinoma of the thyroid with an insular component. We also conducted a review of the literature on this uncommon entity.
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Affiliation(s)
- T T Htwe
- Discipline of Pathology, Universiti Kuala Lumpur - Royal College of Medicine Perak, 3 Jalan Greentown, Ipoh 30450, Perak, Malaysia.
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Talukder S, Khan SH, Karim N. SP1-50 Current status update on non-communicable diseases in Bangladesh. Br J Soc Med 2011. [DOI: 10.1136/jech.2011.142976n.27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Htwe TT, Karim N, Wong J, Jahanfar S, Mansur MA. Differential expression of galectin-3 in advancing thyroid cancer cells: a clue toward understanding tumour progression and metastasis. Singapore Med J 2010; 51:856-859. [PMID: 21140111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
INTRODUCTION Galectin-3 is a member of the beta-galactoside-binding protein family that plays an important role in cell-to-cell adhesion and in cell-to-matrix interaction. Cellular expression of galectin-3 is correlated with cancer aggressiveness and metastasis. METHODS We examined the differential expression of galectin-3 in a collection of 142 cases of thyroid lesions, including 108 cases of papillary thyroid carcinoma (PTC) and 34 cases of follicular carcinoma (FCA). An immunohistochemical method was applied and semiquantitative scoring was performed on the staining intensity of the positive tissue. Scoring was done on cells at the central portion of the tumour foci and on cells at the periphery that were adjacent to the neighbouring normal thyroid tissue matrix. RESULTS A significantly higher expression (p is 0.001) of galectin-3 was observed in the advancing peripheral thyroid cancer cells compared to the centrally located cells that were not in close contact with the neighbouring stromal tissue in cases with PTC compared to those with FCA. CONCLUSION This finding supported the role of galectin-3 in its cell-to-cell adhesion and cell-to-matrix interaction. Galectin-3 is a potential tumour marker for indicating local and distance metastasis, especially in cases with PTC.
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Affiliation(s)
- T T Htwe
- University Kuala Lumpur-Royal College of Medicine Perak, Ipoh 30450, Malaysia.
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Fuhrmann J, Leicht R, Karim N. Estimation of Structural Heterogeneity in Radical Copolymerized Polymer Networks by Comparison with Structural Homogeneous Model Networks. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19850891108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Karim N, Russell V, Shukla B, Thalacker C, Velamakanni S. Adper easy bond in total-etch mode on dentin. Dent Mater 2010. [DOI: 10.1016/j.dental.2009.11.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Abstract
OBJECTIVE Inhibin A and B (Inh A and B), activin A (Act A) as well as FSH may play an important role in bone turnover in perimenopausal women. Data in men are lacking. The aim was to investigate the relationship between circulating concentrations of Inh B and Act A and FSH/LH/testosterone (T) and their contribution to bone mineral density (BMD) in a male population. DESIGN AND SUBJECTS Cross-sectional case-control study of 156 men, 63 with osteoporosis and 93 controls, aged (mean [SD]) 57.7 [13.7] years. MEASUREMENTS Areal (aBMD) was measured at the femoral neck, total hip and lumbar spine. Volumetric BMD (vBMD) was calculated at the femoral neck and lumbar spine. Risk factors were assessed including the measurement of LH/FSH/T, Inh B and Act A. RESULTS After correction for age and body mass index (BMI), associations were found between Inh B and FSH (beta regression coefficient beta = -0.326; P < 0.0001), T (beta = -0.36; P = 0.019) and Act A (beta = -0.4; P = 0.007) and between Inh B and LH (beta = 0.23; P < 0.0001) in all patients. The controls had higher Inh B concentrations compared to the cases (Inh B: controls: 139 [86] pg/ml vs. cases 88 [51] pg/ml; P = 0.005). Act A tended to be lower in the controls (Act A: controls 0.63 [0.24] ng/ml vs. cases 0.75 [0.4] ng/ml; P = 0.056). Univariate regression analyses showed a positive association between Inh B and BMD (P < 0.01) at the lumbar spine and total hip. In contrast a negative association was seen between FSH and BMD at the lumbar spine and femoral neck (P < 0.01). In a partial multivariate regression model that included the gonadal factors only, a positive association was seen between Inh B and BMD at the hip (beta = 0.088; P = 0.04). When all hormones including the gonadotrophins were entered in a full multivariate model, FSH and LH were found to be better predictors of BMD than Inh B or Act A in the controls and cases. CONCLUSIONS These data suggest that the gonadal peptides and gonadotrophins may play a role in the maintenance of bone mass in men. Future confirmatory longitudinal studies are needed.
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Affiliation(s)
- N Karim
- Department of Chemical Pathology, St Thomas Hospital, London, UK
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Abstract
We use an experimental introduction in nature to examine factors that influence parallel evolution. In 1996, 200 high-predation guppies (Poecilia reticulata) from the Yarra River were introduced into the Damier River, which previously lacked guppies. Eight years later, we quantified the colour of wild-caught guppies ('phenotypic' divergence) and lab-reared guppies ('genetic' divergence) from low- and high-predation environments in both rivers. Phenotypic and genetic divergence between predation environments within the Yarra was evident for black and for orange. Phenotypic divergence within the Damier was parallel to the Yarra for black but not for orange. Genetic divergence was absent between predation environments within the Damier, but was evident when comparing both Damier populations to their Yarra ancestors. The evolution of male colour thus depends on factors other than the simple contrast between 'high' and 'low' predation. We suggest that the parallel evolution of male signalling traits may sometimes first require the parallel evolution of female preferences.
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Affiliation(s)
- N Karim
- Redpath Museum and Department of Biology, McGill University, Montréal, QC, Canada
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Low B, Liong M, Yuen K, Chee C, Chong W, Leong W, Karim N, Cheah P. PD-03.05. Urology 2006. [DOI: 10.1016/j.urology.2006.08.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Rajendra S, Ackroyd R, Karim N, Mohan C, Ho JJ, Kutty MK. Loss of human leucocyte antigen class I and gain of class II expression are early events in carcinogenesis: clues from a study of Barrett's oesophagus. J Clin Pathol 2006; 59:952-7. [PMID: 16467164 PMCID: PMC1860487 DOI: 10.1136/jcp.2005.031575] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Human leucocyte antigen (HLA) expression is altered in oesophageal carcinomas compared with normal tissue. It is unclear, however, whether this phenotype precedes malignant transformation or results as a consequence of it. AIM To investigate HLA class I and II expression in Barrett's oesophagus and normal squamous oesophageal tissue. METHODS Asian patients with Barrett's oesophagus (n = 64) and a control group (n = 60) with a normal oesophagus but without reflux symptoms were recruited using endoscopic and histopathological criteria. Tissue samples were stained with monoclonal antibodies specific for HLA-ABC, HLA-DR alpha chain or HLA-DP/DQ/DR, and scored semiquantitatively. The results of immunohistochemical staining were correlated with clinical and histopathological characteristics of patients. RESULTS Marked expression of HLA-ABC was observed in 50% of Barrett's oesophagus sections as compared with 68.3% of controls (p = 0.038). HLA-DR staining was seen in 51.6% of Barrett's oesophagus samples versus 11.7% of controls (p<0.001). Expression of HLA-DP/DQ/DR was evident in 73.4% of oesophageal intestinal metaplasia tissue as opposed to 18.3% of controls (p<0.001). Importantly, a total loss of HLA-ABC and a concomitant gain of HLA-DP/DQ/DR expression were seen in 37.5% of patients with Barrett's oesophagus but in none of the controls (p<0.001). Interestingly, this phenotype was associated positively with dysplasia (adjusted p, p* = 0.031) but negatively with non-steroidal anti-inflammatory drug use (p* = 0.004). CONCLUSIONS HLA class I expression is down regulated and class II expression is up regulated in Barrett's oesophagus. As these changes predate malignant transformation, altered major histocompatibility complex expression may be a key event in disease progression, possibly in facilitating evasion from immune surveillance.
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Affiliation(s)
- S Rajendra
- Division of Gastroenterology, Department of Medicine, Royal College of Medicine, Perak, Malaysia.
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Darnal HK, Karim N, Kamini K, Angela K. The profile of lymphadenopathy in adults and children. Med J Malaysia 2005; 60:590-8. [PMID: 16515110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Surgical biopsies of lymphnodes of 315 patients (273 adult and 42 children) were reviewed microscopically and analysed. The sex ratio was similar in adults but in children males were twice than female (2:1). Ethnically Malay patients predominated in both the groups. The commonest cause of biopsied lymphadenopathy in adults were malignancy (47%) followed by chronic nonspecific lymphadenitis (20%) and granulomatous lymphadenitis (9%) while in children chronic nonspecific lymphadenitis was the commonest (46%) followed by granulomatous lymphadentitis (21%) and malignancy (14%). Twenty percent of adults and 4% of children had normal lymphnodes. Secondary deposits in adult males and females were of squamous cell carcinoma and adenocarcinoma type respectively. In our study 100% of clildren and 96% of adults with granulomatous lymphadenitis had tubercular lesions.
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Affiliation(s)
- H K Darnal
- Department of Pathology, Royal College of Medicine Perak, No. 3, Jalan Greentown, Ipoh, Perak, Malaysia
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41
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Inwoley KA, Sawadogo D, Mizero L, Salou M, Karim N, Sangaré A. [Immunophenotyping of acute leukemias: diagnostic and pronostic utility in Abidjan, Côte d'Ivoire]. Bull Soc Pathol Exot 2004; 97:319-22. [PMID: 15787262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Flow cytometry is nowadays the first-line method for immunophenotypic identification of blast cells but is not so usual in limited-resources countries. We have investigated on the usefulness of this tool in Abidjan, Côte d'Ivoire. Bone marrow sample from 13 patients with acute leukemia identified by cytology and cytochemical analysis was immunophenotyped by using monoclonal antibodies directed to: T lymphoid cells (CD3, CD5, CD7); B lymphoid cells (CD10, CD19, CD20, CD22, HLA-DR) and myeloid cells (CD13, CD33). Immunophenotyping allowed us to confirm the diagnosis of 6 de novo acute leukemias (2 acute myeloid leukaemias, 4 acute lymphoid leukemias) and 7 acute leukaemias resulting from chronic myeloid leukaemias. Immunophenotyping also characterizes the atypical/aberrant lineage essential for the prognosis: 2 biphenotypic acute leukemias (myeloid/lymphoid T) were identified. Our results suggest that flow cytometry may be a useful additional tool to identify the specific leukemic cell, to make a better classification as well as a prognosis evaluation of patients with acute leukemias.
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MESH Headings
- Acute Disease
- Adolescent
- Adult
- Antigens, CD/analysis
- Antigens, Neoplasm/analysis
- B-Lymphocytes/chemistry
- B-Lymphocytes/pathology
- Blast Crisis/diagnosis
- Blast Crisis/pathology
- Bone Marrow Examination
- Child
- Cote d'Ivoire/epidemiology
- Cross-Sectional Studies
- Female
- Flow Cytometry
- Humans
- Immunophenotyping
- Leukemia/classification
- Leukemia/diagnosis
- Leukemia/epidemiology
- Leukemia/pathology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Leukemia, Myeloid, Acute/diagnosis
- Leukemia, Myeloid, Acute/pathology
- Male
- Middle Aged
- Myeloid Cells/chemistry
- Myeloid Cells/pathology
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology
- Prognosis
- T-Lymphocytes/chemistry
- T-Lymphocytes/pathology
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Affiliation(s)
- K A Inwoley
- Département d'hématologie, d'immunologie et de biologie cellulaire, Unité de formation et de recherche des sciences pharmaceutiques et biologiques, Université de Cocody, Abidjan, Côte d'Ivoire.
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Rajendra S, Kadir ZA, Karim N, Zain Z. Ulcerative colitis and motor neurone disease: causal or coincidental? Singapore Med J 2003; 44:423-5. [PMID: 14700423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
Neurological involvement associated with inflammatory bowel disease is well established though rarely reported in the literature. The coexistence of motor neurone disease with ulcerative colitis has never been previously documented. The case of a 53-year-old Indian male with distal ulcerative colitis who, two and a half years later, developed dysarthria, dysphagia, a wasted fasciculating tongue and palatal palsy characteristic of bulbar type motor neurone disease is described. Topical and oral steroids together with azathioprine and mesalazine suppositories controlled the bowel symptoms but did not improve the neurological deficit. Subsequently, the antiglutamate agent riluzole improved the mobility of his tongue. The close temporal relationship and relative infrequency of both these conditions in a Malaysian population along with the recognised association between ulcerative colitis and other neurological conditions deserve careful consideration as to whether a common denominator is involved. Documentation of coexistence of both disorders in a single patient is important in case similar associations are reported in future.
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Affiliation(s)
- S Rajendra
- Department of Medicine, Perak College of Medicine, 3 Jalan Greentown, 30450 Ipoh, Malaysia.
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Damji KF, Sohocki MM, Khan R, Gupta SK, Rahim M, Loyer M, Hussein N, Karim N, Ladak SS, Jamal A, Bulman D, Koenekoop RK. Leber's congenital amaurosis with anterior keratoconus in Pakistani families is caused by the Trp278X mutation in the AIPL1 gene on 17p. Can J Ophthalmol 2001; 36:252-9. [PMID: 11548141 DOI: 10.1016/s0008-4182(01)80018-1] [Citation(s) in RCA: 29] [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] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Leber's congenital amaurosis (LCA) represents the earliest and severest form of retinal dystrophy leading to congenital blindness. A total of 20% of children attending blind schools have this disease. LCA has a multigenic basis and is proving central to our understanding of the development of the retina. We describe the clinical and molecular genetic features of four inbred pedigrees from neighbouring remote villages in northern Pakistan, in which some of the affected members have concurrent keratoconus. METHODS History-taking and physical and eye examinations were performed in the field. Venipuncture, DNA extraction, studies of linkage to known LCA genes, automated sequencing and polymorphism analyses for haplotype assessments were done. RESULTS We examined 12 affected and 15 unaffected family members. By history, there were an additional nine blind people in the four pedigrees. In each pedigree a consanguineous marriage was evident. We found a homozygous nonsense mutation in the AIPL1 gene, which replaces a tryptophan with a stop codon (Trp278X). The phenotype is severe and variable, despite the common molecular genetic etiology in each family. Affected patients had hand motion to no light perception vision and fundus findings ranging from maculopathy to diffuse pigmentary retinopathy. Three affected members had definite keratoconus, and two were suspects based on mild cone formation in the cornea of at least one eye. INTERPRETATION We have identified four Pakistani families with a severe form of LCA that is associated with severe keratoconus in some affected members. The molecular etiology in all four families is a homozygous nonsense mutation, Trp278X, in the photoreceptor-pineal gene AIPL1. To our knowledge, this is one of the first phenotype-genotype correlations of AIPL1-associated LCA.
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MESH Headings
- Adaptor Proteins, Signal Transducing
- Adolescent
- Adult
- Aged
- Blindness/ethnology
- Blindness/genetics
- Carrier Proteins/genetics
- Child
- Child, Preschool
- Chromosomes, Human, Pair 17
- Codon, Nonsense
- Codon, Terminator
- Consanguinity
- DNA Mutational Analysis
- Eye Proteins
- Female
- Genetic Linkage
- Haplotypes
- Humans
- Keratoconus/ethnology
- Keratoconus/genetics
- Male
- Middle Aged
- Optic Atrophy, Hereditary, Leber/ethnology
- Optic Atrophy, Hereditary, Leber/genetics
- Pakistan/epidemiology
- Pedigree
- Polymorphism, Genetic
- Retinitis Pigmentosa/ethnology
- Retinitis Pigmentosa/genetics
- Tryptophan
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Affiliation(s)
- K F Damji
- Ottawa Hospital Research Institute, Ont.
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Karim N, Choe CK. Laboratory accidents--a matter of attitude. Malays J Pathol 2000; 22:85-9. [PMID: 16329540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
This is a prospective study on accidents occurring in the Pathology laboratories of Hospital Ipoh over the 3-year period from January 1996 to October 1999. 15 mishaps were recorded. The location of the accidents were the histology (40%), microbiology (33%), haematology (20%) and cytology (7%) laboratories. No mishaps were reported from the clinical chemistry, blood bank and outpatient laboratories. Cuts by sharp objects were the most common injuries sustained (47%) followed by splashes and squirts by fluid such as blood or chemicals (27%). There was 1 case each of contact with biohazardous fluid, burn, allergy and accidental drinking of disinfectant. 67% of the accidents involved medical laboratory technicians, 20% involved attendants and the rest were medical officers and the junior laboratory technicians. Although the accidents reported appeared trivial, it is vital to document them and bring them to the attention of all concerned in the laboratory, in order to prevent major accidents and also because of medico-legal implications. The role of the Laboratory Safety Committee cannot be overemphasised. Modification of staff attitude is considered an important remedial goal.
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Affiliation(s)
- N Karim
- Department of Pathology, Hospital Ipoh, Perak, Darul Ridzuan, Malaysia
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Steinhoff G, Stock U, Karim N, Mertsching H, Timke A, Meliss RR, Pethig K, Haverich A, Bader A. Tissue engineering of pulmonary heart valves on allogenic acellular matrix conduits: in vivo restoration of valve tissue. Circulation 2000; 102:III50-5. [PMID: 11082362 DOI: 10.1161/01.cir.102.suppl_3.iii-50] [Citation(s) in RCA: 181] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Tissue engineering using in vitro-cultivated autologous vascular wall cells is a new approach to biological heart valve replacement. In the present study, we analyzed a new concept to process allogenic acellular matrix scaffolds of pulmonary heart valves after in vitro seeding with the use of autologous cells in a sheep model. METHODS AND RESULTS Allogenic heart valve conduits were acellularized by a 48-hour trypsin/EDTA incubation to extract endothelial cells and myofibroblasts. The acellularization procedure resulted in an almost complete removal of cells. After that procedure, a static reseeding of the upper surface of the valve was performed sequentially with autologous myofibroblasts for 6 days and endothelial cells for 2 days, resulting in a patchy cellular restitution on the valve surface. The in vivo function was tested in a sheep model of orthotopic pulmonary valve conduit transplantation. Three of 4 unseeded control valves and 5 of 6 tissue-engineered valves showed normal function up to 3 months. Unseeded allogenic acellular control valves showed partial degeneration (2 of 4 valves) and no interstitial valve tissue reconstitution. Tissue-engineered valves showed complete histological restitution of valve tissue and confluent endothelial surface coverage in all cases. Immunohistological analysis revealed cellular reconstitution of endothelial cells (von Willebrand factor), myofibroblasts (alpha-actin), and matrix synthesis (procollagen I). There were histological signs of inflammatory reactions to subvalvar muscle leading to calcifications, but these were not found in valve and pulmonary artery tissue. CONCLUSIONS The in vitro tissue-engineering approach using acellular matrix conduits leads to the in vivo reconstitution of viable heart valve tissue.
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Affiliation(s)
- G Steinhoff
- Leibniz Research Laboratories for Biotechnology and Artificial Organs Department of Thoracic and Cardiovascular Surgery, Medical School Hannover, Hannover, Germany
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Abstract
OBJECTIVES Short latency visual evoked potentials (SVEP), in response to high-intensity flashes from light emitting diodes (LED), were used to detect subclinical effects along the visual pathway in four groups of subjects with different levels of exposure to gasoline, all within legally acceptable limits. METHODS Potentials and exposure levels were obtained from 31 subjects with different occupational exposure levels to gasoline fumes, as well as from 17 non-exposed control subjects. SVEP were recorded from four electrode sites (infra-orbital, Cz, Pz, Oz), in response to flashes presented to each eye in turn from goggle-mounted LEDs. SVEP components were defined after digital filtering, which eliminated the high-frequency oscillatory potentials and accentuated five major components: a periocular P30, attributed to the retina; a fronto-central N50, attributed to the optic nerve; centro-parietal P65 and N85, attributed to the optic tracts and radiation; and an occipital, cortical P105. RESULTS The latencies of successive SVEP components of the exposed subjects showed a significant latency prolongation compared to controls, beginning with activity attributed to the optic nerve and increasing cumulatively with the later components. Retinal components were not affected by the exposure to organic solvents. Among the exposed groups, differences in latency prolongation corresponded to occupational exposure. CONCLUSION The low-frequency components of SVEP were reliably measured and proved to be sensitive to subclinical effects of organic solvents on conduction along the visual pathway. These components are likely to be sensitive to other subcortical visual pathway lesions, but their clinical promise needs further verification.
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Affiliation(s)
- H Pratt
- Evoked Potentials Laboratory, Behavioral Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel
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Mertsching H, Karim N, Haverich A, Bader A. Investigations on biological safety and immunologic aspects of chimeric bioartificial vessels in xenotransplantation. Transplant Proc 2000; 32:1165. [PMID: 10936403 DOI: 10.1016/s0041-1345(00)01168-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- H Mertsching
- Medical School Hannover, Leibniz Research Laboratories for Biotechnology and Artificial Organs, Hannover, Germany
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Karim N, Leong SW. Evaluation of nutritional status among a group of young Chinese adults in Kuala Lumpur, Malaysia. Asia Pac J Clin Nutr 2000; 9:82-6. [PMID: 24394392 DOI: 10.1046/j.1440-6047.2000.00145.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A nutritional status study was carried out among a group of young Chinese adults, aged between 19 and 25, in Kuala Lumpur, Malaysia. Subjects comprised 108 young adults (55 women, 53 men) who were students at two institutes of higher learning. Physical characteristics were evaluated by anthropometric measurements while food intake was determined with a 3-day food record. Blood cholesterol and triglyceride were assessed using the Reflotron analyser. Birthweight was obtained from birth certificates or by proxy. The results showed that the mean body mass index (BMI) for men and women was 21.4 ± 3.3 and 20.0 ± 2.0, respectively, indicating normal weight. Further analysis of BMI classification demonstrated that 28% of men and 39% of women were underweight, 11% of men and 2% of women were overweight while 2% of men were obese. Mean waist-to-hip ratio showed that the subjects had a low risk of developing cardiovascular disease (0.72 ± 0.03 women; 0.81 ± 0.05 men). Mean energy intake was 8841 ± 1756 kJ per day for men and 6426 ± 1567 kJ per day for women. Closer analysis of energy intake of the subjects showed that 86% of men and 91% of women were consuming below the Malaysian recommendation for energy. Nutrients found to be deficient in at least one third of women were calcium, vitamin A, niacin and iron. Mean cholesterol intake in the diet was 278.7 ± 108.7 mg in men and 207.0 ± 82.5 mg in women and there was a significant difference between genders. Blood cholesterol and triglyceride levels were 3.88 ± 0.76 mmol/L and 1.08 ± 0.33 mmol/L, respectively in men, while these levels were lower in women, 3.87 ± 0.80 mmol/L for cholesterol and 0.99 ± 0.29 mmol/L for triglyceride. A general trend of higher mean blood cholesterol and triglyceride levels was shown in adults who were born with lower birthweights.
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Affiliation(s)
- N Karim
- Department of Nutrition and Dietetics, Faculty of Allied Health Sciences, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
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Murray S, Bliss P, Karim N, Calam J, Taylor GW. Analysis of N(alpha)-methylhistamine by gas chromatography-mass spectrometry. J Chromatogr B Biomed Sci Appl 2000; 739:337-44. [PMID: 10755377 DOI: 10.1016/s0378-4347(99)00569-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A gas chromatography-electron capture mass spectrometry assay has been developed for the histamine H3 receptor agonist, N(alpha)-methylhistamine (N(alpha)-MH). The assay is linear from 50 pg-10 ng, with a limit of detection of 50 pg/ml for gastric juice and plasma, and 50 pg/sample for bacteria (10(7)-10(8) CFU) and gastric tissue (5-10 mg wet weight). The limits of quantification are 100 pg/ml for gastric juice (%RSD=1.4) and plasma (%RSD=9.4), and 100 pg/sample for bacteria (%RSD=3.9) and tissue (%RSD=5.8). N(alpha)-MH was not present in human plasma, but low levels (1.4 ng/ml and 0.4 ng/ml) were detected in two samples of human gastric juice obtained from patients infected with Helicobacter pylori.
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Affiliation(s)
- S Murray
- Division of Medicine, Imperial College School of Medicine, London, UK
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50
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Thedinga E, Karim N, Kraft T, Brenner B. A single-fiber in vitro motility assay. In vitro sliding velocity of F-actin vs. unloaded shortening velocity in skinned muscle fibers. J Muscle Res Cell Motil 1999; 20:785-96. [PMID: 10730581 DOI: 10.1023/a:1005658825375] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We describe an approach that allows us to form a micro in vitro motility assay with as little myosin as can be retrieved from a short (approximately 10 mm) segment of a single skinned skeletal muscle fiber (diameter some 100 microm). Myosin is directly extracted from the single fiber segment by a high ionic strength solution in the presence of MgATP, and the extracted myosin is immediately applied to a miniaturized flow cell that has been pretreated with BSA. The observed sliding velocities of fluorescently labeled F-actin are essentially identical with those reported in the literature. Since at the single fiber level most muscle fibers contain only a single myosin heavy chain isoform this approach allows us to determine without additional purification steps, the sliding velocity driven by myosins with different heavy chain isoforms. In addition, this approach can be used to directly correlate under identical experimental conditions unloaded shortening velocity measured in segments of skinned muscle fibers with the in vitro sliding velocity of fluorescently labeled F-actin by extraction of myosin from the same skinned fibers. Such direct correlation was performed with different myosin heavy chain isoforms as well as at different temperatures and ionic strengths. Under all conditions studied, unloaded shortening velocity was 4- to 8-fold faster than sliding velocity in the motility assay even at high temperature (22 degrees C) and ionic strengths >50 mM. This suggests that sliding velocity in the motility assay is limited by additional factors beyond those thought to limit velocity of unloaded shortening in muscle fibers. One such factor might be unspecific ionic interactions between F-actin and the substrate in the motility assay resulting in somewhat higher sensitivity for ionic strength of sliding velocity in the motility assay. This might become of special relevance when using in vitro sliding velocity in assessing functional consequences of mutations involving charged residues of actin or myosin.
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Affiliation(s)
- E Thedinga
- Department of Molecular and Cell Physiology, Medical School Hannover, Germany
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