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Milstein JA, Beer D, Thomson J, Cedars A, Konstantinidis K. Atrial Fibrillation Ablation in a Patient With SV ASD and PAPVR Preceding Transcatheter Septal Closure. JACC Case Rep 2023; 15:101862. [PMID: 37283841 PMCID: PMC10240272 DOI: 10.1016/j.jaccas.2023.101862] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 03/23/2023] [Accepted: 04/03/2023] [Indexed: 06/08/2023]
Abstract
Atrial fibrillation (AF) is common in adults with unrepaired atrial septal defects (ASDs). Sinus venosus (SV) ASDs associated with partial anomalous pulmonary venous return (PAPVR) are traditionally managed surgically. We report the first AF catheter ablation in a patient with SV ASD and PAPVR preceding transcatheter ASD repair with a covered stent. (Level of Difficulty: Advanced.).
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Affiliation(s)
- Jenna A. Milstein
- Division of Cardiology, Johns Hopkins Medicine, Baltimore, Maryland, USA
| | - Dominik Beer
- Geisinger Heart Institute, Danville, Pennsylvania, USA
| | - John Thomson
- Division of Cardiology, Johns Hopkins Medicine, Baltimore, Maryland, USA
| | - Ari Cedars
- Division of Cardiology, Johns Hopkins Medicine, Baltimore, Maryland, USA
| | - Klitos Konstantinidis
- Division of Cardiology, Johns Hopkins Medicine, Baltimore, Maryland, USA
- Division of Cardiology, University of Utah School of Medicine, Salt Lake City, Utah, USA
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Winter F, Beer D, Morawska M, Dorfer C, Roessler K. P07.03.A Advances in Robotic Navigated Laser Craniotomy. An in-vivo non-recovery animal study. Neuro Oncol 2022. [DOI: 10.1093/neuonc/noac174.135] [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
Background
We previously described a new frameless stereotactic intervention using robotic guided laser beam for depth electrode placement. This study tested the feasibility of a new cutting strategy for angulated precision bone channels as well as improved cut-through detection using optical coherence tomography (OCT) and a new generation of co-axial live video feed.
Material and Methods
Preoperative CT scans were performed to plan trajectories for bone channels angulated 45, 60, and 90° relative to the surface. The animals were prepared under general anesthesia by a trained veterinarian conforming European requirements and Good Laboratory Practice regulations. A new cutting strategy was implemented consisting of two circular paths and three different ablation phases. After cut-through detection bolts and depth electrodes were inserted. Before termination ad-hoc planned laser craniotomies were performed to evaluate possible cortex damage.
Results
70 robotic guided laser beam precision bone channels were cut in four pig specimens. Bolts and depth electrodes were implanted solely guided by the trajectory given by the laser precision channels. The new cutting strategy showed no irregularities for either cylindrical (n=38, 45°=10, 60°14, 90°=14) or anti-conical (n=33, 45°=11, 60°=13, 90°=9) bone channels. Angulation and hole diameter showed no significant difference between cylindrical and anti-conical cutting strategies. The updated co-axial camera live video feed in addition to OCT reliably detected cut-through in 80% of cases. Insertion of bolts with firm fit was achieved in 94% of bone channels. All four anesthesia protocols showed no irregularities. No unintended damage to the cortex was detected after laser guided craniotomy.
Conclusion
The new cutting strategy showed promising results in 70 precision bone channels for angulated cylindrical and anti-conical channels in a large in-vivo non-recovery animal study. OCT signal and a new co-axial camera proved its feasibility for cut-through detection. Robotic guided laser beam techniques proved its feasibility for the placement of depth electrodes and might be a suitable option to optimize the burr hole for biopsies.
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Affiliation(s)
- F Winter
- Medical University of Vienna , Vienna , Austria
| | - D Beer
- Advanced Osteotomy Tools , Basel , Switzerland
| | - M Morawska
- Advanced Osteotomy Tools , Basel , Switzerland
| | - C Dorfer
- Medical University of Vienna , Vienna , Austria
| | - K Roessler
- Medical University of Vienna , Vienna , Austria
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3
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Beer D, Berger RD. New Ablation Technology Keeps Getting Cooler. JACC Clin Electrophysiol 2022; 8:1040-1041. [PMID: 35981792 DOI: 10.1016/j.jacep.2022.06.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 06/15/2022] [Indexed: 11/16/2022]
Affiliation(s)
- Dominik Beer
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ronald D Berger
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA; Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA.
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Isakadze N, Engels MC, Beer D, McClellan R, Yanek LR, Mondaloo B, Hays AG, Metkus TS, Calkins H, Barth AS. C-reactive Protein Elevation Is Associated With QTc Interval Prolongation in Patients Hospitalized With COVID-19. Front Cardiovasc Med 2022; 9:866146. [PMID: 35811700 PMCID: PMC9261932 DOI: 10.3389/fcvm.2022.866146] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 04/28/2022] [Indexed: 12/27/2022] Open
Abstract
Background The relationship between inflammation and corrected QT (QTc) interval prolongation is currently not well defined in patients with COVID-19. Objective This study aimed to assess the effect of marked interval changes in the inflammatory marker C-reactive protein (CRP) on QTc interval in patients hospitalized with COVID-19. Methods In this retrospective cohort study of hospitalized adult patients admitted with COVID-19 infection, we identified 85 patients who had markedly elevated CRP levels and serial measurements of an ECG and CRP during the same admission. We compared mean QTc interval duration, and other clinical and ECG characteristics between times when CRP values were high and low. We performed mixed-effects linear regression analysis to identify associations between CRP levels and QTc interval in univariable and adjusted models. Results Mean age was 58 ± 16 years, of which 39% were women, 41% were Black, and 25% were White. On average, the QTc interval calculated via the Bazett formula was 15 ms higher when the CRP values were “high” vs. “low” [447 ms (IQR 427–472 ms) and 432 ms (IQR 412–452 ms), respectively]. A 100 mg/L increase in CRP was associated with a 1.5 ms increase in QTc interval [β coefficient 0.15, 95% CI (0.06–0.24). In a fully adjusted model for sociodemographic, ECG, and clinical factors, the association remained significant (β coefficient 0.14, 95% CI 0.05–0.23). Conclusion An interval QTc interval prolongation is observed with a marked elevation in CRP levels in patients with COVID-19.
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Affiliation(s)
- Nino Isakadze
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Marc C. Engels
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Dominik Beer
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Rebecca McClellan
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Lisa R. Yanek
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Bahareh Mondaloo
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Allison G. Hays
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Thomas S. Metkus
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Hugh Calkins
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Andreas S. Barth
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- *Correspondence: Andreas S. Barth
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Beer D, Calkins H. Evidence to Support Rhythm Control Is Superior to Rate Control as Treatment for Atrial Fibrillation. JACC Clin Electrophysiol 2022; 8:633-634. [PMID: 35589175 DOI: 10.1016/j.jacep.2022.03.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 03/26/2022] [Indexed: 10/18/2022]
Affiliation(s)
- Dominik Beer
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hugh Calkins
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
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Beer D, Subzposh FA, Colburn S, Naperkowski A, Vijayaraman P. His bundle pacing capture threshold stability during long-term follow-up and correlation with lead slack. Europace 2021; 23:757-766. [PMID: 33236070 DOI: 10.1093/europace/euaa350] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 10/26/2020] [Indexed: 11/13/2022] Open
Abstract
AIMS His bundle pacing (HBP) is the most physiologic form of pacing. Long-term HBP capture threshold stability and its relation to lead characteristics at the time of implantation have not been adequately described. The aim of this study was to characterize HB capture threshold in follow-up and to identify potential lead characteristics predictive of lead capture instability. METHODS AND RESULTS Consecutive patients with successful HBP for bradycardia indications were identified from the Geisinger HBP registry. His bundle capture thresholds, baseline comorbidities, and radiographic lead slack characteristics were analysed. An increase in HB capture threshold ≥1 V above implant values at any time during follow-up was tracked. Forty-four of the 294 studied (15%) experienced HB capture threshold increase by ≥ 1 V. Threshold increase was seen early (41% by 8 weeks, 66% by 1 year). Eighteen (6%) patients required lead revision in follow-up. Abnormal slack shape was associated with a trend toward capture threshold increase [hazard ratio (HR) 2.07; 95% confidence interval (CI) 0.9-4.6; P = 0.08]. Non-perpendicular angle of lead insertion on radiography was associated with the capture threshold increase (HR 2.81, 95% CI 1.4-5.8; P < 0.01). CONCLUSION His bundle capture threshold remains stable in the majority (85%) of patients. Implant characteristics may predict the threshold rise. Further evaluation of the aetiology of threshold increase and design changes in lead and delivery systems may lead to chronically stable capture thresholds.
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Affiliation(s)
- Dominik Beer
- Geisinger Commonwealth School of Medicine Director, Cardiac Electrophysiology Geisinger Heart Institute MC 36-10, 1000 E Mountain Blvd Wilkes-Barre, PA 18711, USA
| | - Faiz A Subzposh
- Geisinger Commonwealth School of Medicine Director, Cardiac Electrophysiology Geisinger Heart Institute MC 36-10, 1000 E Mountain Blvd Wilkes-Barre, PA 18711, USA
| | - Shaun Colburn
- Geisinger Commonwealth School of Medicine Director, Cardiac Electrophysiology Geisinger Heart Institute MC 36-10, 1000 E Mountain Blvd Wilkes-Barre, PA 18711, USA
| | - Angela Naperkowski
- Geisinger Commonwealth School of Medicine Director, Cardiac Electrophysiology Geisinger Heart Institute MC 36-10, 1000 E Mountain Blvd Wilkes-Barre, PA 18711, USA
| | - Pugazhendhi Vijayaraman
- Geisinger Commonwealth School of Medicine Director, Cardiac Electrophysiology Geisinger Heart Institute MC 36-10, 1000 E Mountain Blvd Wilkes-Barre, PA 18711, USA
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Vijayaraman P, Patel N, Colburn S, Beer D, Naperkowski A, Subzposh FA. His-Purkinje Conduction System Pacing in Atrioventricular Block: New Insights into Site of Conduction Block. JACC Clin Electrophysiol 2021; 8:73-85. [PMID: 34393084 DOI: 10.1016/j.jacep.2021.07.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/06/2021] [Accepted: 07/12/2021] [Indexed: 10/20/2022]
Abstract
OBJECTIVES This study aims to assess the safety and feasibility of achieving His-Purkinje conduction system pacing (HPCSP) in consecutive patients with atrioventricular block (AVB) and to describe the site of conduction block in patients with infranodal AVB. BACKGROUND HPCSP has evolved as the preferred form of physiologic pacing. Left bundle branch area pacing (LBBAP) has emerged as an effective alternative to His bundle pacing (HBP). METHODS Consecutive patients with AVB referred for pacemaker implantation were included in the study. HBP or LBBAP was attempted in all patients. Site of conduction block was identified as nodal or infranodal (intra-Hisian or infra-Hisian) AVB. RESULTS HPCSP was attempted in 333 consecutive patients with AVB and was successful in 322 (97%) patients. HBP was achieved in 140 patients, LBBAP in 179 patients, and both in 3 patients. Site of conduction block was nodal in 55% and infranodal in 45% (intra-Hisian 89%; infra-Hisian 4%; indeterminate 7%). QRS duration at baseline was 111±27 versus 129±31 (P < 0.001) compared to 126 ± 24 vs 125 ± 21 milliseconds (P = 0.75) during HBP and LBBAP, respectively. HBP thresholds at implant were higher compared to LBBAP (1.2 ± 0.7 V at 0.9 milliseconds vs 0.6 ± 0.3 V at 0.5 milliseconds; P < 0.001) but remained stable during follow-up. Lead revision was required in 3% and 2% of patients with HBP and LBBAP, respectively. CONCLUSIONS HPCSP pacing was successfully performed in 97% of unselected patients with AVB irrespective of the site of conduction block. True infra-Hisian block (distal His-Purkinje conduction disease) is rare. HBP and LBBAP were complementary in achieving stable and low capture thresholds.
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Affiliation(s)
- Pugazhendhi Vijayaraman
- Geisinger Heart Institute, Geisinger Commonwealth School of Medicine, Wilkes-Barre, Pennsylvania, USA.
| | - Neil Patel
- The Wright Center, Scranton, Pennsylvania, USA
| | - Shaun Colburn
- Geisinger Heart Institute, Geisinger Commonwealth School of Medicine, Wilkes-Barre, Pennsylvania, USA
| | - Dominik Beer
- Johns Hopkins University, Baltimore, Maryland, USA
| | - Angela Naperkowski
- Geisinger Heart Institute, Geisinger Commonwealth School of Medicine, Wilkes-Barre, Pennsylvania, USA
| | - Faiz A Subzposh
- Geisinger Heart Institute, Geisinger Commonwealth School of Medicine, Wilkes-Barre, Pennsylvania, USA
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Beer D, Isakadze N, McClellan R, Calkins H, Barth AS. Acquired Long QT and Ventricular Arrhythmias in the Setting of Acute Inflammation: A Case Series. JACC Case Rep 2021; 3:1103-1107. [PMID: 34471893 PMCID: PMC8314122 DOI: 10.1016/j.jaccas.2021.04.034] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 04/21/2021] [Accepted: 04/27/2021] [Indexed: 01/08/2023]
Abstract
We report a case series of 4 patients with transient marked QTc prolongation and ventricular arrhythmias in the setting of inflammation with very high ferritin levels. Three patients were positive for coronavirus disease-2019. In the setting of an acute rise in inflammatory markers, electrocardiography screening for QTc prolongation is warranted. (Level of Difficulty: Beginner.)
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Affiliation(s)
- Dominik Beer
- Department of Medicine, Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Nino Isakadze
- Department of Medicine, Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Rebecca McClellan
- Department of Medicine, Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hugh Calkins
- Department of Medicine, Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Andreas S Barth
- Department of Medicine, Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Carruth ED, Beer D, Alsaid A, Schwartz MLB, McMinn M, Kelly MA, Buchanan AH, Nevius CD, Calkins H, James CA, Murray B, Tichnell C, Matsumura ME, Kirchner HL, Fornwalt BK, Sturm AC, Haggerty CM. Clinical Findings and Diagnostic Yield of Arrhythmogenic Cardiomyopathy Through Genomic Screening of Pathogenic or Likely Pathogenic Desmosome Gene Variants. Circ Genom Precis Med 2021; 14:e003302. [PMID: 33684294 DOI: 10.1161/circgen.120.003302] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Genomic screening holds great promise for presymptomatic identification of hidden disease, and prevention of dramatic events, including sudden cardiac death associated with arrhythmogenic cardiomyopathy (ACM). Herein, we present findings from clinical follow-up of carriers of ACM-associated pathogenic/likely pathogenic desmosome variants ascertained through genomic screening. METHODS Of 64 548 eligible participants in Geisinger MyCode Genomic Screening and Counseling program (2015-present), 92 individuals (0.14%) identified with pathogenic/likely pathogenic desmosome variants by clinical laboratory testing were referred for evaluation. We reviewed preresult medical history, patient-reported family history, and diagnostic testing results to assess both arrhythmogenic right ventricular cardiomyopathy and left-dominant ACM. RESULTS One carrier had a prior diagnosis of dilated cardiomyopathy with arrhythmia; no other related diagnoses or diagnostic family history criteria were reported. Fifty-nine carriers (64%) had diagnostic testing in follow-up. Excluding the variant, 21/59 carriers satisfied at least one arrhythmogenic right ventricular cardiomyopathy task force criterion, 11 (52%) of whom harbored DSP variants, but only 5 exhibited multiple criteria. Six (10%) carriers demonstrated evidence of left-dominant ACM, including high rates of atypical late gadolinium enhancement by magnetic resonance imaging and nonsustained ventricular tachycardia. Two individuals received new cardiomyopathy diagnoses and received defibrillators for primary prevention. CONCLUSIONS Genomic screening for pathogenic/likely pathogenic variants in desmosome genes can uncover both left- and right-dominant ACM. Findings of overt cardiomyopathy were limited but were most common in DSP-variant carriers and notably absent in PKP2-variant carriers. Consideration of the pathogenic/likely pathogenic variant as a major criterion for diagnosis is inappropriate in the setting of genomic screening.
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Affiliation(s)
- Eric D Carruth
- Department of Translational Data Science and Informatics (E.D.C., C.D.N., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Dominik Beer
- The Heart Institute (D.B., A.A., M.E.M., B.K.F., A.C.S., C.M.H.), Geisinger, Danville, PA
| | - Amro Alsaid
- The Heart Institute (D.B., A.A., M.E.M., B.K.F., A.C.S., C.M.H.), Geisinger, Danville, PA
| | - Marci L B Schwartz
- Genomic Medicine Institute (M.L.B.S., M.M., M.A.K., A.H.B., A.C.S.), Geisinger, Danville, PA
| | - Megan McMinn
- Genomic Medicine Institute (M.L.B.S., M.M., M.A.K., A.H.B., A.C.S.), Geisinger, Danville, PA
| | - Melissa A Kelly
- Genomic Medicine Institute (M.L.B.S., M.M., M.A.K., A.H.B., A.C.S.), Geisinger, Danville, PA
| | - Adam H Buchanan
- Genomic Medicine Institute (M.L.B.S., M.M., M.A.K., A.H.B., A.C.S.), Geisinger, Danville, PA
| | - Christopher D Nevius
- Department of Translational Data Science and Informatics (E.D.C., C.D.N., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Hugh Calkins
- Division of Cardiology, Department of Medicine, Johns Hopkins Medical Center, Baltimore, MD (H.C., C.A.J., B.M., C.T.)
| | - Cynthia A James
- Division of Cardiology, Department of Medicine, Johns Hopkins Medical Center, Baltimore, MD (H.C., C.A.J., B.M., C.T.)
| | - Brittney Murray
- Division of Cardiology, Department of Medicine, Johns Hopkins Medical Center, Baltimore, MD (H.C., C.A.J., B.M., C.T.)
| | - Crystal Tichnell
- Division of Cardiology, Department of Medicine, Johns Hopkins Medical Center, Baltimore, MD (H.C., C.A.J., B.M., C.T.)
| | - Martin E Matsumura
- The Heart Institute (D.B., A.A., M.E.M., B.K.F., A.C.S., C.M.H.), Geisinger, Danville, PA
| | - H Lester Kirchner
- Department of Population Health Sciences (H.L.K.), Geisinger, Danville, PA
| | - Brandon K Fornwalt
- Department of Translational Data Science and Informatics (E.D.C., C.D.N., B.K.F., C.M.H.), Geisinger, Danville, PA.,The Heart Institute (D.B., A.A., M.E.M., B.K.F., A.C.S., C.M.H.), Geisinger, Danville, PA.,Department of Radiology (B.K.F.), Geisinger, Danville, PA
| | - Amy C Sturm
- The Heart Institute (D.B., A.A., M.E.M., B.K.F., A.C.S., C.M.H.), Geisinger, Danville, PA.,Genomic Medicine Institute (M.L.B.S., M.M., M.A.K., A.H.B., A.C.S.), Geisinger, Danville, PA
| | - Christopher M Haggerty
- Department of Translational Data Science and Informatics (E.D.C., C.D.N., B.K.F., C.M.H.), Geisinger, Danville, PA.,The Heart Institute (D.B., A.A., M.E.M., B.K.F., A.C.S., C.M.H.), Geisinger, Danville, PA
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Mahmoud O, Beer D, Mahmaljy H, Youniss M, Campoverde EH, Elias H, Stanton M, Patel M, Hashmi I, Young K, Kuppuraju R, Jacobs S, Alsaid A. Prevalence and Predictors of Obstructive Coronary Artery Disease in Nonlow-risk Acute Chest Pain Patients Who Rule Out for Myocardial Infarction in the High-sensitivity Troponin Era. Crit Pathw Cardiol 2021; 20:10-15. [PMID: 32511135 DOI: 10.1097/hpc.0000000000000229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES The best management approach for chest pain patients who rule out for myocardial infarction (MI) in the high-sensitivity troponin (hsTn) era remains elusive. Patients, especially those with nonlow clinical risk scores, are often referred for inpatient ischemic testing to uncover obstructive coronary artery disease (CAD). Whether the prevalence of obstructive CAD in this cohort is high enough to justify routine testing is not known. METHODS We conducted a retrospective cohort analysis of 1517 emergency department chest pain patients who ruled out for MI by virtue of a stable high-sensitivity troponin T (hsTnT) levels (defined as <5 ng/L intermeasurements increase) and were admitted for inpatient testing. RESULTS Abnormal ischemia evaluation (including 5.9% with evidence of fixed wall motion or perfusion defects) was 11.9%. Of those undergoing invasive angiography (n = 292), significant coronary stenoses (≥70% or unstable lesions) and multivessel CAD occurred in 16.8% and 5.5%, respectively. In a multivariate logistic regression model, known CAD, prior MI, chest pain character, mildly elevated hsTnT, and left ventricular ejection fraction <40% were predictive of an abnormal ischemia evaluation result, whereas electrocardiography findings and the modified History, EKG, Age, Risk factors, and troponin (HEART) score were not. Of note, 30-day adverse cardiac events were strikingly low at 0.4% with no deaths despite an overwhelming majority (>90%) of patients scoring intermediate or high on the modified HEART score. CONCLUSIONS A considerable percentage of acute chest pain patients who rule out for MI by hsTn had evidence of obstructive CAD, and the modified HEART score was not predictive of an abnormal ischemia evaluation.
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Affiliation(s)
- Osama Mahmoud
- From the Heart Institute, Geisinger Medical Center, Danville, PA
| | - Dominik Beer
- From the Heart Institute, Geisinger Medical Center, Danville, PA
| | - Hadi Mahmaljy
- From the Heart Institute, Geisinger Medical Center, Danville, PA
| | - Mohamed Youniss
- From the Heart Institute, Geisinger Medical Center, Danville, PA
| | | | - Hadi Elias
- From the Heart Institute, Geisinger Medical Center, Danville, PA
| | - Matthew Stanton
- Department of Internal Medicine, Geisinger Medical Center, Danville, PA
| | - Maulin Patel
- Department of Internal Medicine, Geisinger Medical Center, Danville, PA
| | - Insia Hashmi
- Department of Internal Medicine, Geisinger Medical Center, Danville, PA
| | - Katelyn Young
- Department of Internal Medicine, Geisinger Medical Center, Danville, PA
| | - Rajesh Kuppuraju
- Department of Internal Medicine, Geisinger Medical Center, Danville, PA
| | - Steven Jacobs
- Department of Internal Medicine, Geisinger Medical Center, Danville, PA
| | - Amro Alsaid
- From the Heart Institute, Geisinger Medical Center, Danville, PA
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Ravi V, Beer D, Pietrasik GM, Hanifin JL, Ooms S, Ayub MT, Larsen T, Huang HD, Krishnan K, Trohman RG, Vijayaraman P, Sharma PS. Development of New-Onset or Progressive Atrial Fibrillation in Patients With Permanent HIS Bundle Pacing Versus Right Ventricular Pacing: Results From the RUSH HBP Registry. J Am Heart Assoc 2020; 9:e018478. [PMID: 33174509 PMCID: PMC7763709 DOI: 10.1161/jaha.120.018478] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Background Conventional right ventricular pacing (RVP) has been associated with an increased incidence of atrial fibrillation (AF). We sought to compare the occurrence of new‐onset AF and assessed AF disease progression during long‐term follow‐up between His bundle pacing (HBP) and RVP. Methods and Results We included patients undergoing initial dual‐chamber pacemaker implants at Rush University Medical Center between January 1, 2016, and June 30, 2019. A total of 360 patients were evaluated, and 225 patients (HBP, n=105; RVP, n=120) were included in the study. Among the 148 patients (HBP, n=72; RVP, n=76) with no history of AF, HBP demonstrated a lower risk of new‐onset AF (adjusted hazard ratio [HR], 0.53; 95% CI, 0.28–0.99; P=0.046) compared with traditional RVP. This benefit was observed with His or RVP burden exceeding 20% (HR, 0.29; 95% CI, 0.13–0.64; P=0.002), ≥40% (HR, 0.31; P=0.007), ≥60% (HR, 0.35; P=0.015), and ≥80% (HR, 0.40; P=0.038). There was no difference with His or RV pacing burden <20% (HR, 0.613; 95% CI, 0.213–1.864; P=0.404). In patients with a prior history of AF, there was no difference in AF progression (P=0.715); however, in a subgroup of patients with a pacing burden ≥40%, HBP demonstrated a trend toward a lower risk of AF progression (HR, 0.19; 95% CI, 0.03–1.16; P=0.072). Conclusions HBP demonstrated a lower risk of new‐onset AF compared with RVP, which was primarily observed at a higher pacing burden.
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Affiliation(s)
- Venkatesh Ravi
- Division of Cardiology Department of Medicine Rush University Medical Center Chicago IL
| | - Dominik Beer
- Division of Cardiology Department of Medicine Geisinger Heart Institute Wilkes-Barre PA
| | - Grzegorz M Pietrasik
- Division of Cardiology Department of Medicine John H Stroger Jr Hospital of Cook County Chicago IL
| | - Jillian L Hanifin
- Division of Cardiology Department of Medicine Rush University Medical Center Chicago IL
| | - Sara Ooms
- Division of Cardiology Department of Medicine Rush University Medical Center Chicago IL
| | - Muhammad Talha Ayub
- Division of Cardiology Department of Medicine Rush University Medical Center Chicago IL
| | - Timothy Larsen
- Division of Cardiology Department of Medicine Rush University Medical Center Chicago IL
| | - Henry D Huang
- Division of Cardiology Department of Medicine Rush University Medical Center Chicago IL
| | - Kousik Krishnan
- Division of Cardiology Department of Medicine Rush University Medical Center Chicago IL
| | - Richard G Trohman
- Division of Cardiology Department of Medicine Rush University Medical Center Chicago IL
| | | | - Parikshit S Sharma
- Division of Cardiology Department of Medicine Rush University Medical Center Chicago IL
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Beer D, Harjai K, Bauch TD, Vijayaraman P. Percutaneous Extraction of an Embolized IVC Filter Strut Embedded in the Right Ventricle. JACC Case Rep 2020; 2:2318-2322. [PMID: 34317163 PMCID: PMC8304553 DOI: 10.1016/j.jaccas.2020.07.054] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/22/2020] [Accepted: 07/29/2020] [Indexed: 11/30/2022]
Abstract
The incidence of IVC filter fracture is high with risk for embolization and may require open surgery. We present a minimally invasive approach of complex transcatheter extraction of an embolized and embedded IVC filter strut from the right ventricle. (Level of Difficulty: Intermediate.)
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Affiliation(s)
| | | | | | - Pugazhendhi Vijayaraman
- Address for correspondence: Dr. Pugazhendhi Vijayaraman, Cardiac Electrophysiology, Geisinger Commonwealth School of Medicine, Geisinger Heart Institute, MC 36-10, 1000 East Mountain Boulevard, Wilkes-Barre, Pennsylvania 18711, USA.
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13
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Carruth ED, Young W, Beer D, James CA, Calkins H, Jing L, Raghunath S, Hartzel DN, Leader JB, Kirchner HL, Smelser DT, Carey DJ, Kelly MA, Sturm AC, Alsaid A, Fornwalt BK, Haggerty CM. Prevalence and Electronic Health Record-Based Phenotype of Loss-of-Function Genetic Variants in Arrhythmogenic Right Ventricular Cardiomyopathy-Associated Genes. Circ Genom Precis Med 2019; 12:e002579. [PMID: 31638835 DOI: 10.1161/circgen.119.002579] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Arrhythmogenic right ventricular cardiomyopathy (ARVC) is associated with variants in desmosome genes. Secondary findings of pathogenic/likely pathogenic variants, primarily loss-of-function (LOF) variants, are recommended for clinical reporting; however, their prevalence and associated phenotype in a general clinical population are not fully characterized. METHODS From whole-exome sequencing of 61 019 individuals in the DiscovEHR cohort, we screened for putative loss-of-function variants in PKP2, DSC2, DSG2, and DSP. We evaluated measures from prior clinical ECG and echocardiograms, manually over-read to evaluate ARVC diagnostic criteria, and performed a PheWAS (phenome-wide association study). Finally, we estimated expected penetrance using Bayesian inference. RESULTS One hundred forty individuals (0.23%; 59±18 years old at last encounter; 33% male) had an ARVC variant (G+). None had an existing diagnosis of ARVC in the electronic health record, nor significant differences in prior ECG or echocardiogram findings compared with matched controls without variants. Several G+ individuals satisfied major repolarization (n=4) and ventricular function (n=5) criteria, but this prevalence matched controls. PheWAS showed no significant associations of other heart disease diagnoses. Combining our best genetic and disease prevalence estimates yields an estimated penetrance of 6.0%. CONCLUSIONS The prevalence of ARVC loss-of-function variants is ≈1:435 in a general clinical population of predominantly European descent, but with limited electronic health record-based evidence of phenotypic association in our population, consistent with a low penetrance estimate. Prospective deep phenotyping and longitudinal follow-up of a large sequenced cohort is needed to determine the true clinical relevance of an incidentally identified ARVC loss-of-function variant.
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Affiliation(s)
- Eric D Carruth
- Department of Imaging Science and Innovation (E.D.C., L.J., S.R., B.K.F., C.M.H.), Geisinger, Danville, PA.,Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Wilson Young
- The Heart Institute (W.Y., D.B., A.A., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Dominik Beer
- The Heart Institute (W.Y., D.B., A.A., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Cynthia A James
- Department of Medicine, Division of Cardiology, Johns Hopkins Medical Center, Baltimore, MD (C.A.J., H.C.)
| | - Hugh Calkins
- Department of Medicine, Division of Cardiology, Johns Hopkins Medical Center, Baltimore, MD (C.A.J., H.C.)
| | - Linyuan Jing
- Department of Imaging Science and Innovation (E.D.C., L.J., S.R., B.K.F., C.M.H.), Geisinger, Danville, PA.,Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Sushravya Raghunath
- Department of Imaging Science and Innovation (E.D.C., L.J., S.R., B.K.F., C.M.H.), Geisinger, Danville, PA.,Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Dustin N Hartzel
- Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Joseph B Leader
- Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - H Lester Kirchner
- Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Diane T Smelser
- Department of Molecular and Functional Genomics (D.T.S., D.J.C.), Geisinger, Danville, PA
| | - David J Carey
- Department of Molecular and Functional Genomics (D.T.S., D.J.C.), Geisinger, Danville, PA
| | - Melissa A Kelly
- Genomic Medicine Institute (M.A.K., A.C.S.), Geisinger, Danville, PA
| | - Amy C Sturm
- Genomic Medicine Institute (M.A.K., A.C.S.), Geisinger, Danville, PA
| | - Amro Alsaid
- The Heart Institute (W.Y., D.B., A.A., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Brandon K Fornwalt
- Department of Imaging Science and Innovation (E.D.C., L.J., S.R., B.K.F., C.M.H.), Geisinger, Danville, PA.,Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA.,The Heart Institute (W.Y., D.B., A.A., B.K.F., C.M.H.), Geisinger, Danville, PA.,Department of Radiology (B.K.F.), Geisinger, Danville, PA
| | - Christopher M Haggerty
- Department of Imaging Science and Innovation (E.D.C., L.J., S.R., B.K.F., C.M.H.), Geisinger, Danville, PA.,Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA.,The Heart Institute (W.Y., D.B., A.A., B.K.F., C.M.H.), Geisinger, Danville, PA
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Bueno R, Harpole D, Tsao M, Beer D, Watson M, Shepherd F, Richards W, Ballman K, Wang X, Chen Z, Govindan R, Chen G, Rivard C, Hirsch F. OA13.01 SPECS2 Lung Cancer Consortium Prospective Multicenter Validation of Prognostic Signature for Early Stage Squamous Lung Cancer. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.477] [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: 11/25/2022]
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15
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Affiliation(s)
- Dominik Beer
- Geisinger Heart Institute, Geisinger Commonwealth School of Medicine, MC 36-10, 1000 E Mountain Blvd, Wilkes-Barre, PA, USA
| | - Gopi Dandamudi
- Department of Cardiology, CHI-Franciscan, Tacoma, WA, USA
| | - John M Mandrola
- Department of Cardiology, Baptist Health Louisville, Louisville, KY, USA
| | | | - Pugazhendhi Vijayaraman
- Geisinger Heart Institute, Geisinger Commonwealth School of Medicine, MC 36-10, 1000 E Mountain Blvd, Wilkes-Barre, PA, USA
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16
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Beer D, Sharma PS, Subzposh FA, Naperkowski A, Pietrasik GM, Durr B, Qureshi M, Panikkath R, Abdelrahman M, Williams BA, Hanifin JL, Zimberg R, Austin K, Macuch B, Trohman RG, Vanenkevort EA, Dandamudi G, Vijayaraman P. Clinical Outcomes of Selective Versus Nonselective His Bundle Pacing. JACC Clin Electrophysiol 2019; 5:766-774. [PMID: 31320004 DOI: 10.1016/j.jacep.2019.04.008] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 04/24/2019] [Accepted: 04/24/2019] [Indexed: 11/17/2022]
Abstract
OBJECTIVES The aim of the study was to evaluate the clinical outcomes of nonselective (NS) His bundle pacing (HBP) compared with selective (S) HBP. BACKGROUND HBP is the most physiologic form of ventricular pacing. NS-HBP results in right ventricular septal pre-excitation due to fusion with myocardial capture in addition to His bundle capture resulting in widened QRS duration compared with S-HBP wherein there is exclusive His bundle capture and conduction. METHODS The Geisinger and Rush University HBP registries comprise 640 patients who underwent successful HBP. Our study population included 350 consecutive patients treated with HBP for bradyarrhythmic indications who demonstrated ≥20% ventricular pacing burden 3 months post-implantation. Patients were categorized into S-HBP or NS-HBP based on QRS morphology (NS-HBP n = 232; S-HBP n = 118) at the programmed output at the 3-month follow-up. The primary analysis outcome was a combined endpoint of all-cause mortality or heart failure hospitalization. RESULTS The NS-HBP group had a higher number of men (64% vs. 50%; p = 0.01), higher incidence of infranodal atrioventricular block (40% vs. 9%; p < 0.01), ischemic cardiomyopathy (24% vs. 14%; p = 0.03), and permanent atrial fibrillation (18% vs. 8%; p = 0.01). The primary endpoint occurred in 81 of 232 patients (35%) in the NS-HBP group compared with 23 of 118 patients (19%) in the S-HBP group (hazard ratio: 1.38; 95% confidence interval: 0.87 to 2.20; p = 0.17). Subgroup analyses of patients at greatest risk (higher pacing burden or lower left ventricular ejection fraction) revealed no incremental risk with NS-HBP. CONCLUSIONS NS-HBP was associated with similar outcomes of death or heart failure hospitalization when compared with S-HBP. Multicenter risk-matched clinical studies are needed to confirm these findings.
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Affiliation(s)
- Dominik Beer
- Division of Cardiology, Geisinger Heart Institute, Wilkes Barre, Pennsylvania
| | - Parikshit S Sharma
- Division of Cardiology, Rush University Medical Center, Chicago, Illinois
| | - Faiz A Subzposh
- Division of Cardiology, Geisinger Heart Institute, Wilkes Barre, Pennsylvania
| | - Angela Naperkowski
- Division of Cardiology, Geisinger Heart Institute, Wilkes Barre, Pennsylvania
| | | | - Brendan Durr
- Division of Cardiology, Geisinger Heart Institute, Wilkes Barre, Pennsylvania
| | - Maria Qureshi
- Division of Cardiology, Geisinger Heart Institute, Wilkes Barre, Pennsylvania
| | - Ragesh Panikkath
- Division of Cardiology, Geisinger Heart Institute, Wilkes Barre, Pennsylvania
| | - Mohamed Abdelrahman
- Division of Cardiology, Weil Cornell Medicine-New York Presbyterian Hospital, New York, New York
| | - Brent A Williams
- Division of Cardiology, Geisinger Heart Institute, Wilkes Barre, Pennsylvania
| | - Jillian L Hanifin
- Division of Cardiology, Rush University Medical Center, Chicago, Illinois
| | - Ryan Zimberg
- Division of Cardiology, Rush University Medical Center, Chicago, Illinois
| | - Kelly Austin
- Division of Cardiology, Geisinger Heart Institute, Wilkes Barre, Pennsylvania
| | - Brooke Macuch
- Division of Cardiology, Geisinger Heart Institute, Wilkes Barre, Pennsylvania
| | - Richard G Trohman
- Division of Cardiology, Rush University Medical Center, Chicago, Illinois
| | | | - Gopi Dandamudi
- Division of Cardiology, Indiana University, Indianapolis, Indiana
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Beer D, Subzposh FA, Vijayaraman P. The continuing search for physiologic pacing. Aging (Albany NY) 2019; 11:2177-2178. [PMID: 31029058 PMCID: PMC6519995 DOI: 10.18632/aging.101928] [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] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Accepted: 04/22/2019] [Indexed: 11/25/2022]
Affiliation(s)
- Dominik Beer
- Division of Cardiac Electrophysiology, Geisinger Heart Institute, Geisinger Commonwealth School of Medicine, Wilkes-Barre, PA 18711, USA
| | - Faiz A. Subzposh
- Division of Cardiac Electrophysiology, Geisinger Heart Institute, Geisinger Commonwealth School of Medicine, Wilkes-Barre, PA 18711, USA
| | - Pugazhendhi Vijayaraman
- Division of Cardiac Electrophysiology, Geisinger Heart Institute, Geisinger Commonwealth School of Medicine, Wilkes-Barre, PA 18711, USA
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Yu H, Chen Z, Ballman K, Watson M, Govindan R, Beer D, Bueno R, Herman M, Franklin W, Gandara D, Joshi M, Merrick D, Richards W, Rivard C, Shepherd F, Tsao M, Bokhoven A, Harpole D, Hirsch F. P1.04-23 Expression of Emerging Immunotherapy Targets in Early-Stage Squamous Lung Carcinoma. J Thorac Oncol 2018. [DOI: 10.1016/j.jtho.2018.08.738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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19
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Abdelrahman M, Subzposh FA, Beer D, Durr B, Naperkowski A, Sun H, Oren JW, Dandamudi G, Vijayaraman P. Clinical Outcomes of His Bundle Pacing Compared to Right Ventricular Pacing. J Am Coll Cardiol 2018. [DOI: 10.1016/j.jacc.2018.02.048] [Citation(s) in RCA: 311] [Impact Index Per Article: 51.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Hoffmann O, Regenauer M, Löwe R, Dehn-Rotfelser KV, Funke I, Burges A, Beer D, Mayer B. Identification of the most effective chemotherapy in recurrent ovarian cancer using the spheroid model. Geburtshilfe Frauenheilkd 2014. [DOI: 10.1055/s-0034-1388455] [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] Open
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Beer D, Friese K, Fürst S, Göß C, Hertlein L, Lenhard M, Grandl S, Heinemann V, Burges A. Individualized management of Aggressive Angiomyxoma: A case report. Geburtshilfe Frauenheilkd 2014. [DOI: 10.1055/s-0034-1388509] [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] Open
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22
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Arnold F, Margraf D, Hoffmann O, Dehn-Rotfelser KV, Funke I, Loewe R, Burges A, Beer D, Werner J, Mayer B. Tumor biology driven treatment selection in primary ovarian cancer. Geburtshilfe Frauenheilkd 2014. [DOI: 10.1055/s-0034-1388483] [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] Open
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23
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Rao SPS, Lakshminarayana SB, Kondreddi RR, Herve M, Camacho LR, Bifani P, Kalapala SK, Jiricek J, Ma NL, Tan BH, Ng SH, Nanjundappa M, Ravindran S, Seah PG, Thayalan P, Lim SH, Lee BH, Goh A, Barnes WS, Chen Z, Gagaring K, Chatterjee AK, Pethe K, Kuhen K, Walker J, Feng G, Babu S, Zhang L, Blasco F, Beer D, Weaver M, Dartois V, Glynne R, Dick T, Smith PW, Diagana TT, Manjunatha UH. Indolcarboxamide Is a Preclinical Candidate for Treating Multidrug-Resistant Tuberculosis. Sci Transl Med 2013; 5:214ra168. [DOI: 10.1126/scitranslmed.3007355] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Zhang L, Mudumbi P, Beer D, Day R, Robinson VM, Ghosh P, Esberg DB, Rothman SA, Kramer RK, Day F, Kowey PR. Abstract 424: Fish Oils Reduce the Risk of Stroke in Patients with Hypertension. Hypertension 2012. [DOI: 10.1161/hyp.60.suppl_1.a424] [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: 11/16/2022]
Abstract
BACKGROUND:
Hypertension (HTN) is a major cause of stroke. Previous studies showed evidence that long term fish oil consumption can prevent stroke in men but it has not been thoroughly investigated in patients with HTN. This study aimed to determine the prevalence of stroke or transient ischemic attack (TIA) in HTN patients consuming fish oils.
METHODS
Medical records of HTN patients were retrieved randomly from two hospital based cardiology outpatient clinics. The prevalence of stroke/TIA was investigated in patients with and without taking fish oils and the compliance of fish oil intake was further investigated by a follow-up survey. The use of anticoagulant agents, angiotensin-converting enzyme inhibitors (ACE), angiotensin receptor blockers (ARBs) and beta-blockers (BB) was also compared between two groups.
RESULTS
After taking fish oils (2±1 g) daily for a median duration of 4 yrs (95% CI: 3, 5 yrs) none of HTN patients in the fish oil group developed stroke/TIA whereas events of stroke/TIA occurred in 8% of HTN patients in the non-fish oil group (Table 1). No difference was found in the concomitant use of ACE, ARBs and BB in the two groups and the effect of fish oil was not influenced by anticoagulants.
CONCLUSIONS:
Our findings suggest that long term fish oil consumption can reduce the risk of stroke in patients with hypertension. This simple approach may help reduce the healthcare burden and improve the quality of life by preventing stroke in patients with hypertension.
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Affiliation(s)
- Li Zhang
- Lankenau Med Cntr, Lankenau Institute for Med Rsch, Jefferson Med College, Wynnewood, PA
| | - Praveen Mudumbi
- Lankenau Med Cntr, Lankenau Institute for Med Rsch, Jefferson Med College, Wynnewood, PA
| | - Dominik Beer
- Lankenau Med Cntr, Lankenau Institute for Med Rsch, Jefferson Med College, Wynnewood, PA
| | - Roseann Day
- Lankenau Med Cntr, Lankenau Institute for Med Rsch, Jefferson Med College, Wynnewood, PA
| | - Victoria M Robinson
- Lankenau Med Cntr, Lankenau Institute for Med Rsch, Jefferson Med College, Wynnewood, PA
| | - Pradeepto Ghosh
- Lankenau Med Cntr, Lankenau Institute for Med Rsch, Jefferson Med College, Wynnewood, PA
| | - Douglas B Esberg
- Lankenau Med Cntr, Lankenau Institute for Med Rsch, Jefferson Med College, Wynnewood, PA
| | - Steven A Rothman
- Lankenau Med Cntr, Lankenau Institute for Med Rsch, Jefferson Med College, Wynnewood, PA
| | - R. Kyle Kramer
- Lankenau Med Cntr, Lankenau Institute for Med Rsch, Jefferson Med College, Wynnewood, PA
| | - Francis Day
- Bryn Mawr Hosp, Main Line Health, Bryn Mawr, PA
| | - Peter R Kowey
- Lankenau Med Cntr, Lankenau Institute for Med Rsch, Jefferson Med College, Wynnewood, PA
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Gravel J, Fitzpatrick E, Millar K, Curtis S, Joubert G, Boutis K, Guimont C, Goldman RD, Dubrovsky S, Porter R, Beer D, Osmond MH. Validity of the Canadian Triage and Acuity Scale for Children: A Multi-Centre, Database Study. Paediatr Child Health 2012. [DOI: 10.1093/pch/17.suppl_a.21aa] [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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MacLeod DIA, Beer D. The extended Maxwellian view. J Vis 2010. [DOI: 10.1167/3.9.341] [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: 11/24/2022] Open
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Beer D, Becker M, Anstis S, MacLeod D. Polarity-specific masking of isoluminant colors. J Vis 2010. [DOI: 10.1167/2.7.546] [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: 11/24/2022] Open
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Kurabachew M, Lu SHJ, Krastel P, Schmitt EK, Suresh BL, Goh A, Knox JE, Ma NL, Jiricek J, Beer D, Cynamon M, Petersen F, Dartois V, Keller T, Dick T, Sambandamurthy VK. Lipiarmycin targets RNA polymerase and has good activity against multidrug-resistant strains of Mycobacterium tuberculosis. J Antimicrob Chemother 2008; 62:713-9. [DOI: 10.1093/jac/dkn269] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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Beer D, Rüdt R. Die pseudotumoröse Kalzinose bei chronischer Niereninsuffizienz. AKTUEL RHEUMATOL 2008. [DOI: 10.1055/s-2008-1043582] [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: 10/21/2022]
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Jin Z, Mori Y, Yang J, Sato F, Ito T, Cheng Y, Paun B, Hamilton JP, Kan T, Olaru A, David S, Agarwal R, Abraham JM, Beer D, Montgomery E, Meltzer SJ. Hypermethylation of the nel-like 1 gene is a common and early event and is associated with poor prognosis in early-stage esophageal adenocarcinoma. Oncogene 2007; 26:6332-40. [PMID: 17452981 DOI: 10.1038/sj.onc.1210461] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The nel-like1 (NELL1) gene maps to chromosome 11p15, which frequently undergoes loss of heterozygosity in esophageal adenocarcinoma (EAC). NELL1 promoter hypermethylation was examined by real-time methylation-specific polymerase chain reaction in 259 human esophageal tissues. Hypermethylation of this promoter showed highly discriminative receiver-operator characteristic curve profiles, clearly distinguishing esophageal squamous cell carcinoma (ESCC) and EAC from normal esophagus (NE) (P<0.001). NELL1 normalized methylation values were significantly higher in Barrett's metaplasia (BE), dysplastic Barrett's (D) and EAC than in NE (P<0.0000001). NELL1 hypermethylation frequency was zero in NE but increased early during neoplastic progression, to 41.7% in BE from patients with Barrett's alone, 52.5% in D and 47.8% in EAC. There was a significant correlation between NELL1 hypermethylation and BE segment length. Three (11.5%) of 26 ESCCs exhibited NELL1 hypermethylation. Survival correlated inversely with NELL1 hypermethylation in patients with stages I-II (P=0.0264) but not in stages III-IV (P=0.68) EAC. Treatment of KYSE220 ESCC and BIC EAC cells with 5-aza-2'-deoxycytidine reduced NELL1 methylation and increased NELL1 mRNA expression. NELL1 mRNA levels in EACs with an unmethylated NELL1 promoter were significantly higher than those in EACs with a methylated promoter (P=0.02). Promoter hypermethylation of NELL1 is a common, tissue-specific event in human EAC, occurs early during Barrett's-associated esophageal neoplastic progression, and is a potential biomarker of poor prognosis in early-stage EAC.
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Affiliation(s)
- Z Jin
- Division of Gastroenterology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
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Brichory F, Beer D, Le Naour F, Giordano T, Hanash S. Proteomics-based identification of protein gene product 9.5 as a tumor antigen that induces a humoral immune response in lung cancer. Cancer Res 2001; 61:7908-12. [PMID: 11691811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
We used a proteomic approach to identify proteins that commonly induce an antibody response in lung cancer. Sera from 64 newly diagnosed patients with lung cancer, 99 patients with other types of cancer, and 71 noncancer controls were analyzed for antibody-based reactivity against lung adenocarcinoma proteins resolved by two-dimensional PAGE. Unlike controls, autoantibodies against a protein identified by mass spectrometry as protein gene product 9.5 (PGP 9.5) were detected in sera from 9 of 64 patients with lung cancer. Circulating PGP 9.5 antigen was detected in sera from two additional patients with lung cancer, without detectable PGP 9.5 autoantibodies. PGP 9.5 is a neurospecific polypeptide previously proposed as a marker for non-small cell lung cancer, based on its expression in tumor tissue. Using A549 lung adenocarcinoma cell line, we have demonstrated that PGP 9.5 was present at the cell surface, as well as secreted. Thus, the findings of PGP 9.5 antigen and/or antibodies in serum of patients with lung cancer suggest that PGP 9.5 may have utility in lung cancer screening and diagnosis.
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Affiliation(s)
- F Brichory
- Department of Pediatrics, University of Michigan, Ann Arbor, Michigan 48109, USA
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Abstract
We have developed a comprehensive approach to identifying molecular changes in lung cancer that includes both genomic and proteomic analyses. The related effort has produced a large amount of data pertaining to gene expression at the RNA and protein levels. As a result, we have constructed a database that contains protein expression data on lung cancer as well as other relevant data including DNA microarray derived data. A large number of proteins that are expressed in different types of lung cancer have been identified and have been correlated with the expression measures for their corresponding genes at the RNA level. The database is intended to facilitate our effort at developing novel classification schemes for lung cancer and the identification of novel markers for early diagnosis.
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Affiliation(s)
- J M Oh
- University of Michigan Medical Center, 1150 W. Medical Center Drive, A520 Medical Science Research Building I, Ann Arbor, MI 48109-0656, USA
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Beer D, Bettschart V. [Abdominal pain]. Rev Med Suisse Romande 2001; 121:33-40. [PMID: 11234707] [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: 04/16/2023]
Abstract
The doctor on duty conducting home visits is frequently asked to care for patients with non-traumatic severe abdominal pain. For this reason, visiting doctors should be able to recognize tell-tale alarm signs, evaluate ailments that call for surgical referral to--particularly those that require emergency surgery--and, if necessary, perform simple paraclinical exams at the patient's bedside. In the case of intense abdominal pain requiring a rapid and effective "analgesia", the doctor should be able to administer an opiate, without of the surgical unit impairing the judgement. When hospitalisation or referral for surgery is not necessary, a re-evaluation at 12 to 36 hours later should be offered.
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Affiliation(s)
- D Beer
- Policlinique Médicale Universitaire, César-Roux 19, 1005 Lausanne
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Abstract
We have developed a comprehensive approach to the identification of protein markers in lung cancer that includes profiling of tumor tissue and cell lines as well as the analysis of serum for autoantibodies to lung tumor antigens. A large number of proteins that are differentially expressed in the major subtypes of lung cancer have been identified by mass spectrometry. A database of protein expression in lung cancer and other types of cancer has been constructed that integrates two-dimensional gel profiles, mass spectrometry data, quantitative protein data and gene expression data at the RNA level, that serves as a resource for biomarker identification. Analysis of the serological response in lung cancer has led to the identification of novel markers detectable in serum of lung cancer patients at the time of diagnosis. The proteomic approach is likely to yield novel classification schemes and novel markers for early diagnosis of lung cancer.
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Affiliation(s)
- S Hanash
- Department of Pediatrics, University of Michigan Medical Center, A520 Medical Science Research Bldg. I, 1150 W. Medical Center Drive, Ann Arbor, MI 48109, USA.
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Leonard HL, Swedo SE, Garvey M, Beer D, Perlmutter S, Lougee L, Karitani M, Dubbert B. Postinfectious and other forms of obsessive-compulsive disorder. Child Adolesc Psychiatr Clin N Am 1999; 8:497-511. [PMID: 10442228] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The search for subtypes of OCD has led to increased appreciation of the importance of distinguishing early (prepubertal) versus later on-set, and of tic-related versus non-tic related subtypes, as well as postinfectious forms of the disorder. How these apparent typologies relate to each other remains to be elucidated. Careful longitudinal clinical descriptive studies, as well as the ongoing application of genetic, neuroimaging, and immunologic techniques, promise to advance our understanding of how genotype and environmental factors interact to produce the diverse clinical forms of OCD and to point the way to more effective treatment.
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Affiliation(s)
- H L Leonard
- Division of Child and Adolescent Psychiatry, Rhode Island Hospital, Providence, USA.
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Papageorgiou AC, Quinn CP, Beer D, Brehm RD, Tranter HS, Bonventre PF, Acharya KR. Crystal structure of a biologically inactive mutant of toxic shock syndrome toxin-1 at 2.5 A resolution. Protein Sci 1996; 5:1737-41. [PMID: 8844860 PMCID: PMC2143494 DOI: 10.1002/pro.5560050826] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Toxic shock syndrome toxin-1 (TSST-1) is one of a family of staphylococcal exotoxins recognized as microbial superantigens. The toxin plays a dominant role in the genesis of toxic shock in humans through a massive activation of the immune system. This potentially lethal illness occurs as a result of the interaction of TSST-1 with a significant proportion of the T-cell repertoire. TSST-1, like other superantigens, can bind directly to class II major histocompatibility (MHC class II) molecules prior to its interaction with entire families of V beta chains of the T-cell receptor (TCR). The three-dimensional structure of a mutant (His-135-Ala) TSST-1 was compared with the structure of the native (wild-type) TSST-1 at 2.5 A resolution. The replacement of His 135 of TSST-1 with an Ala residue results in the loss of T-cell mitogenicity and toxicity in experimental animals. This residue, postulated to be directly involved in the toxin-TCR interactions, is located on the major helix alpha 2, which forms the backbone of the molecule and is exposed to the solvent. In the molecular structure of the mutant toxin, the helix alpha 2 remains unaltered, but the His to Ala modification causes perturbations on the neighboring helix alpha 1 by disrupting helix-helix interactions. Thus, the effects on TCR binding of the His 135 residue could actually be mediated, wholly or in part, by the alpha 1 helix.
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Affiliation(s)
- A C Papageorgiou
- School of Biology and Biochemistry, University of Bath, Claverton Down, United Kingdom
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Abstract
Multiple personality disorder is the classification given a person for whom two or more distinct personalities are diagnosed. The personalities can be different and vary in character from aggressive to submissive (victimized). The victim alters can be abused and abuse or mutilate self to relieve anxiety or guilt (deserving punishment) or to exert control. Alters may provide a means of expressing anger or other feelings. Aggression towards the body may be sexually oriented, so one may ask whether aggression could make self-rape possible. If so, such expression of self-injuries may be observed in a person with multiple personality as when one alter may injure another. Clinical case material is presented on this concept for a woman who had been formally diagnosed with multiple personality disorder.
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Probst MR, Beer M, Beer D, Jenö P, Meyer UA, Gasser R. Human liver arylacetamide deacetylase. Molecular cloning of a novel esterase involved in the metabolic activation of arylamine carcinogens with high sequence similarity to hormone-sensitive lipase. J Biol Chem 1994; 269:21650-6. [PMID: 8063807] [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: 01/28/2023] Open
Abstract
Microsomal arylacetamide deacetylase (DAC) competes against the activity of cytosolic arylamine N-acetyltransferase, which catalyzes one of the initial biotransformation pathways for arylamine and heterocyclic amine carcinogens in many species and tissues. Activity determination and immunoblot analysis of DAC in human target tissues for arylamine carcinogens revealed that in extrahepatic tissues, additional enzymes are responsible for any deacetylation activity, whereas a single enzyme predominantly catalyzes this hydrolytic reaction in liver. We isolated and characterized a full-length cDNA from a human liver lambda gt11 library. This clone encodes an open reading frame of 400 amino acids with a deduced molecular mass of 45.7 kDa and contains two putative glycosylation sites. The 3'-untranslated region contains two putative polyadenylation signals. The cDNA was confirmed to be that for DAC in tryptic peptides from the purified human liver protein. Highest sequence similarity of DAC was found in a series of prokaryotic esterases encompassing the putative active site. Two extended regions of significant sequence homology with hormone-sensitive lipase and with lipase 2 from Moraxella TA144 were identified, whereas similarity to carboxyl esterases was restricted to the region encompassing the putative active site, indicating that DAC should be classified as esterase. This cDNA provides an important tool to study deacetylation and its effects on the metabolic activation of arylamine and heterocyclic amine carcinogens.
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Affiliation(s)
- M R Probst
- Department of Pharmacology, Biocenter of the University, Basel, Switzerland
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Probst M, Beer M, Beer D, Jenö P, Meyer U, Gasser R. Human liver arylacetamide deacetylase. Molecular cloning of a novel esterase involved in the metabolic activation of arylamine carcinogens with high sequence similarity to hormone-sensitive lipase. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)31855-0] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Abstract
'Unitary psychosis' is the collective name for a set of disparate doctrines whose common denominator is the view that there is only one form of psychosis and that its diverse clinical presentations can be explained in terms of endogenous and exogenous factors. This paper examines the history of these doctrines since the eighteenth century in the work of their main sponsors and extricates their conceptual assumptions. It is shown that the nature of the debate between 'unitarians' and those who believed in the existence of separate diseases has changed throughout time, and that to these changes national differences have been important. Earlier discussions made use of conceptual and ontological argument; latter ones of clinical analysis; and the latest debate, that occurred during the 1970s, over-relied on statistical techniques and genetic analysis. The outcome of this long debate remains inconclusive.
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Hoff P, Beer D. Introductory remarks on the translation of Emil Kraepelin's paper Die Erscheinungsformen des Irreseins (1920). Hist Psychiatry 1992; 3:499-29. [PMID: 11612918 DOI: 10.1177/0957154x9200301206] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Fischer M, Beer D, von Wrangell U. [Local infiltration thrombolysis of arterial occlusions with tissue plasminogen activator]. Med Klin (Munich) 1992; 87:563-6. [PMID: 1470051] [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: 12/27/2022]
Abstract
Only few reports deal with local low dose thrombolysis of peripheral arterial occlusions by the infiltration technique with recombinant human tissue plasminogen activator (rTPA). We report the treatment of 45 cases (38 patients, 13 times women and 32 times men, aged 33 to 86 years). The patients suffered from thrombotic occlusions of the femoropopliteal artery (n = 39), a femoro-popliteal PTFE bypass (n = 3), a femorocrural bypass graft (n = 2) or a popliteal embolus (n = 1). The thrombus was infiltrated with 2.5 mg rTPA/hour attenuated to 30 ml normal saline solution. In the mean 7.1 mg rTPA was given. The rate of recanalisation was 76% during the days the patient stayed in hospital. The rate of recanalisation was higher (88%) in 16 cases suffering from acute arterial occlusion (< 24 hours). Even in those cases with undetectable or absent peripheral arterial runoff, therapeutic success was achieved at 92%.
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Affiliation(s)
- M Fischer
- Medizinische Klinik II, Städtisches Klinikum Braunschweig
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Papageorgiou AC, Oikonomakos NG, Leonidas DD, Bernet B, Beer D, Vasella A. The binding of D-gluconohydroximo-1,5-lactone to glycogen phosphorylase. Kinetic, ultracentrifugation and crystallographic studies. Biochem J 1991; 274 ( Pt 2):329-38. [PMID: 1900987 PMCID: PMC1150141 DOI: 10.1042/bj2740329] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Combined kinetic, ultracentrifugation and X-ray-crystallographic studies have characterized the effect of the beta-glucosidase inhibitor gluconohydroximo-1,5-lactone on the catalytic and structural properties of glycogen phosphorylase. In the direction of glycogen synthesis, gluconohydroximo-1,5-lactone was found to competitively inhibit both the b (Ki 0.92 mM) and the alpha form of the enzyme (Ki 0.76 mM) with respect to glucose 1-phosphate in synergism with caffeine. In the direction of glycogen breakdown, gluconohydroximo-1,5-lactone was found to inhibit phosphorylase b in a non-competitive mode with respect to phosphate, and no synergism with caffeine could be demonstrated. Ultracentrifugation and crystallization experiments demonstrated that gluconohydroximo-1,5-lactone was able to induce dissociation of tetrameric phosphorylase alpha and stabilization of the dimeric T-state conformation. A crystallographic binding study with 100 mM-gluconohydroximo-1,5-lactone at 0.24 nm (2.4 A) resolution showed a major peak at the catalytic site, and no significant conformational changes were observed. Analysis of the electron-density map indicated that the ligand adopts a chair conformation. The results are discussed with reference to the ability of the catalytic site of the enzyme to distinguish between two or more conformations of the glucopyranose ring.
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Affiliation(s)
- A C Papageorgiou
- Biological Research Center, National Hellenic Research Foundation, Athens, Greece
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