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Williams ZJ, Hoagland D, Jourdan J, Gourdie RG. Abstract P1092: Voltage Gated Sodium Channel Subunit Mimetic Peptide βadp1 Increases Regulated Intramembrane Proteolysis Of Scn1b/β1. Circ Res 2022. [DOI: 10.1161/res.131.suppl_1.p1092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Clinical treatment for cardiac arrhythmias based on targeting ion channels is limited and can have deadly side effects. We previously reported that acute administration of βadp1 resulted in decreased action potential conduction velocity and increased arrhythmias in isolated guinea pig hearts. These changes were associated with disruption of trans-homophilic adhesion of the β1 subunit within gap junction-adjacent perinexal domains in intercalated discs. Using Electric Cell-Substrate Impedance Sensing (ECIS), we found that βadp1 shows opposing acute and long-term effects on β1 mediated adhesion. βadp1 decreases β1 mediated adhesion in 1610 cells stably expressing SCN1B/β1 (1610β1) over the first 24 hours, but after 48 hours is associated with increased adhesion. Regulated Intramembrane Proteolysis (RIP) of β1 sequentially by BACE-1 and γ-secretase results in a cleaved intracellular fragment that translocates to the nucleus and alters transcription of various genes, including VGSC subunits. Therefore, we hypothesized the long-term gain-of-adhesion-function with βadp1 treatment resulted from increased RIP of β1, with downstream VGSC gene expression effects. Inhibition of γ-secretase with DAPT accumulates a C-terminal fragment (CTF) of β1 during RIP, enabling quantification of changes to RIP. Thus, 1610β1 cells were treated with 50μM βadp1, 1μM DAPT, 50μM βadp1+1μM DAPT or 0.1% DMSO control. Cells were fixed for β1 immunofluorescence (IF) or lysate was collected at 6-, 24-, and 48-hours post treatments for Western blotting. DAPT treatment significantly increased CTF levels compared to control at all timepoints (p<.0001). However, βadp1+DAPT treatment resulted in greater accumulation of β1 CTF levels over DAPT alone at each timepoint. (n=6, 6 hr: p<.01, 24 hr: p<.01, 48 hr: p<.05). βadp1+DAPT treatment caused a significant increase in full-length β1 at 6 hours, but no difference at 24 or 48 hours. The data suggest depletion of β1 by increased RIP of β1 after βadp1 treatment. IF showed an increase in abundance of β1 48 hours after βadp1 treatment compared to DMSO. In sum, our data indicates that βadp1 may upregulate RIP of β1 with potential downstream effects on gene transcription of VGSC subunits, suggesting a path to a novel class of antiarrhythmics.
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Teng A, Gu L, Di Paola M, Lakin R, Williams Z, Au A, CHEN WENLIANG, Callaghan NI, Hakem Zadeh F, ZHOU YUQING, Fatah M, Chatterjee D, Jourdan J, Jack L, Simmons CA, Kislinger T, Yip C, Backx P, Gourdie RG, Hamilton RM, Gramolini A. Abstract P2018: Tmem65 Is Critical For The Structure And Function Of The Intercalated Discs In Mouse Hearts. Circ Res 2022. [DOI: 10.1161/res.131.suppl_1.p2018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The intercalated disc (ICD) is unique membrane structure that is indispensable to normal heart function, yet its structural organization is not completely understood. Previously, we showed that the ICD-bound transmembrane protein 65 (Tmem65) was required for connexin 43 (Cx43) localization and function in cultured mouse neonatal cardiomyocytes. Here, we investigated the role of Tmem65 in ICD organization
in vivo
. A mouse model was established by injecting CD1 mouse pups (3-7 days after birth) with recombinant adeno-associated virus 9 (rAAV9) harboring Tmem65 shRNA which resulted in a 90% reduction of Tmem65 expression in mouse ventricles compared to mice injected with scrambled shRNA. Tmem65 knockdown (KD) resulted in increased mortality which was accompanied by eccentric hypertrophic cardiomyopathy within 3 weeks of injection, progressing to dilated cardiomyopathy with severe cardiac fibrosis by 7 weeks post-injection. Tmem65 KD hearts displayed depressed hemodynamics, measured echocardiographically, accompanied by electrocardiogram changes (prolonged PR intervals and QRS duration) consistent with impaired conduction, which was confirmed with optical mapping of isolated hearts. Immunoprecipitation and super-resolution microscopy demonstrated a physical interaction between Tmem65 and sodium channel β subunit (β1) in mouse hearts and this interaction appeared to be required for both the establishment of perinexal nanodomain structure and the localization of both voltage-gated sodium channel 1.5 (NaV1.5) and Cx43 to ICDs. Despite the loss of NaV1.5 at the ICDs, whole-cell patch clamp electrophysiology did not reveal reductions in Na
+
currents but did show reduced Ca
2+
and K
+
currents in Tmem65 KD cardiomyocytes in comparison to control cells. We conclude that disrupting Tmem65 function results in impaired ICD structure, abnormal cardiac electrophysiology, and ultimately cardiomyopathy.
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Affiliation(s)
| | | | | | | | | | - Aaron Au
- Univ of Toronto, Toronto, Canada
| | | | | | | | | | | | | | | | - Liu Jack
- Univ of Toronto, Toronto, Canada
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3
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Marsh SR, Pridham KJ, Jourdan J, Gourdie RG. Novel Protocols for Scalable Production of High Quality Purified Small Extracellular Vesicles from Bovine Milk. Nanotheranostics 2021; 5:488-498. [PMID: 34367882 PMCID: PMC8342262 DOI: 10.7150/ntno.62213] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 06/07/2021] [Indexed: 12/13/2022] Open
Abstract
Extracellular Vesicles (EVs) are cell-secreted nanovesicles that have unique potential for encapsulating and targeting "difficult-to-drug" therapeutic cargos. Milk provides an enriched source of EVs, and of particular interest to the drug delivery field, small EVs. Small EVs are distinguished from large EVs by membrane components, biogenesis mechanism and downstream functionality - in particular, small EVs are primarily composed of exosomes, which show high stability in vivo and naturally function in the targeted delivery of biological materials to cells. Moreover, bovine milk is abundantly produced by the dairy industry, widely consumed, and generally well tolerated by humans. Importantly, there is evidence that milk exosomes and small EVs are efficiently taken up into the circulation from the gut, providing the opportunity for their use in administration of therapeutics such as microRNAs or peptides not typically available via an oral route. Unfortunately, present methods for isolation do not efficiently separate EVs from milk proteins, resulting in contamination that is not desirable in a clinical-grade therapeutic. Herein, we present novel EV purification methods focused on optimized timing and levels of temperature and divalent cation chelation. Incorporation of these solubilization steps into centrifugation- and tangential flow filtration-based methods provide large amounts of purified small EVs at ultra-dense concentrations, which are substantially free from contaminating milk proteins. Remarkably, these ultra-dense isolates equal 10 to 15% of the starting volume of milk indicating a prodigious rate of small EV production by mammary glands. Our approach enables gentle, scalable production of ultrastructurally and functionally intact small EVs from milk, providing a path to their industrial scale purification for oral delivery of therapeutic biologics and small drugs.
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Affiliation(s)
- Spencer R. Marsh
- Fralin Biomedical Research Institute at Virginia Tech Carillion, Roanoke, VA, 24016, USA
- Center for Vascular and Heart Research, Virginia Tech, Roanoke, VA, 24016, USA
| | - Kevin J. Pridham
- Fralin Biomedical Research Institute at Virginia Tech Carillion, Roanoke, VA, 24016, USA
- Center for Vascular and Heart Research, Virginia Tech, Roanoke, VA, 24016, USA
| | - Jane Jourdan
- Fralin Biomedical Research Institute at Virginia Tech Carillion, Roanoke, VA, 24016, USA
- Center for Vascular and Heart Research, Virginia Tech, Roanoke, VA, 24016, USA
| | - Robert G. Gourdie
- Fralin Biomedical Research Institute at Virginia Tech Carillion, Roanoke, VA, 24016, USA
- Center for Vascular and Heart Research, Virginia Tech, Roanoke, VA, 24016, USA
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, 24061, USA
- Department of Emergency Medicine, Virginia Tech Carilion School of Medicine, Virginia Tech, Roanoke, VA, 24016, USA
- Faculty of Health Science, Virginia Tech, Blacksburg, VA, 24061, USA
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4
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Veeraraghavan R, Hoeker GS, Alvarez-Laviada A, Hoagland D, Wan X, King DR, Sanchez-Alonso J, Chen C, Jourdan J, Isom LL, Deschenes I, Smyth JW, Gorelik J, Poelzing S, Gourdie RG. The adhesion function of the sodium channel beta subunit (β1) contributes to cardiac action potential propagation. eLife 2018; 7:37610. [PMID: 30106376 PMCID: PMC6122953 DOI: 10.7554/elife.37610] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [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: 04/17/2018] [Accepted: 08/06/2018] [Indexed: 12/22/2022] Open
Abstract
Computational modeling indicates that cardiac conduction may involve ephaptic coupling – intercellular communication involving electrochemical signaling across narrow extracellular clefts between cardiomyocytes. We hypothesized that β1(SCN1B) –mediated adhesion scaffolds trans-activating NaV1.5 (SCN5A) channels within narrow (<30 nm) perinexal clefts adjacent to gap junctions (GJs), facilitating ephaptic coupling. Super-resolution imaging indicated preferential β1 localization at the perinexus, where it co-locates with NaV1.5. Smart patch clamp (SPC) indicated greater sodium current density (INa) at perinexi, relative to non-junctional sites. A novel, rationally designed peptide, βadp1, potently and selectively inhibited β1-mediated adhesion, in electric cell-substrate impedance sensing studies. βadp1 significantly widened perinexi in guinea pig ventricles, and selectively reduced perinexal INa, but not whole cell INa, in myocyte monolayers. In optical mapping studies, βadp1 precipitated arrhythmogenic conduction slowing. In summary, β1-mediated adhesion at the perinexus facilitates action potential propagation between cardiomyocytes, and may represent a novel target for anti-arrhythmic therapies.
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Affiliation(s)
- Rengasayee Veeraraghavan
- Virginia Tech Carilion Research Institute, Virginia Polytechnic University, Roanoke, United States.,School of Medicine, Virginia Polytechnic University, Roanoke, United States
| | - Gregory S Hoeker
- Virginia Tech Carilion Research Institute, Virginia Polytechnic University, Roanoke, United States.,School of Medicine, Virginia Polytechnic University, Roanoke, United States
| | | | - Daniel Hoagland
- Virginia Tech Carilion Research Institute, Virginia Polytechnic University, Roanoke, United States.,School of Medicine, Virginia Polytechnic University, Roanoke, United States
| | - Xiaoping Wan
- Heart and Vascular Research Center, MetroHealth Medical Center, Department of Medicine, Case Western Reserve University, Cleveland, United States
| | - D Ryan King
- Virginia Tech Carilion Research Institute, Virginia Polytechnic University, Roanoke, United States.,School of Medicine, Virginia Polytechnic University, Roanoke, United States.,Graduate Program in Translational Biology, Medicine and Health, Virginia Tech, Virginia, United States
| | - Jose Sanchez-Alonso
- Department of Myocardial Function, Imperial College London, London, United Kingdom
| | - Chunling Chen
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, United States
| | - Jane Jourdan
- Virginia Tech Carilion Research Institute, Virginia Polytechnic University, Roanoke, United States.,School of Medicine, Virginia Polytechnic University, Roanoke, United States
| | - Lori L Isom
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, United States
| | - Isabelle Deschenes
- Heart and Vascular Research Center, MetroHealth Medical Center, Department of Medicine, Case Western Reserve University, Cleveland, United States.,Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, Unites States
| | - James W Smyth
- Virginia Tech Carilion Research Institute, Virginia Polytechnic University, Roanoke, United States.,School of Medicine, Virginia Polytechnic University, Roanoke, United States.,Department of Biological Sciences, College of Science, Blacksburg, United States
| | - Julia Gorelik
- Department of Myocardial Function, Imperial College London, London, United Kingdom
| | - Steven Poelzing
- Virginia Tech Carilion Research Institute, Virginia Polytechnic University, Roanoke, United States.,School of Medicine, Virginia Polytechnic University, Roanoke, United States.,Department of Biomedical Engineering and Mechanics, Virginia Polytechnic University, Blacksburg, United States
| | - Robert G Gourdie
- Virginia Tech Carilion Research Institute, Virginia Polytechnic University, Roanoke, United States.,School of Medicine, Virginia Polytechnic University, Roanoke, United States.,Department of Biomedical Engineering and Mechanics, Virginia Polytechnic University, Blacksburg, United States
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5
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Mirtl M, T Borer E, Djukic I, Forsius M, Haubold H, Hugo W, Jourdan J, Lindenmayer D, McDowell WH, Muraoka H, Orenstein DE, Pauw JC, Peterseil J, Shibata H, Wohner C, Yu X, Haase P. Genesis, goals and achievements of Long-Term Ecological Research at the global scale: A critical review of ILTER and future directions. Sci Total Environ 2018; 626:1439-1462. [PMID: 29898550 DOI: 10.1016/j.scitotenv.2017.12.001] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 11/28/2017] [Accepted: 12/01/2017] [Indexed: 06/08/2023]
Abstract
Since its founding in 1993 the International Long-term Ecological Research Network (ILTER) has gone through pronounced development phases. The current network comprises 44 active member LTER networks representing 700 LTER Sites and ~80 LTSER Platforms across all continents, active in the fields of ecosystem, critical zone and socio-ecological research. The critical challenges and most important achievements of the initial phase have now become state-of-the-art in networking for excellent science. At the same time increasing integration, accelerating technology, networking of resources and a strong pull for more socially relevant scientific information have been modifying the mission and goals of ILTER. This article provides a critical review of ILTER's mission, goals, development and impacts. Major characteristics, tools, services, partnerships and selected examples of relative strengths relevant for advancing ILTER are presented. We elaborate on the tradeoffs between the needs of the scientific community and stakeholder expectations. The embedding of ILTER in an increasingly collaborative landscape of global environmental observation and ecological research networks and infrastructures is also reflected by developments of pioneering regional and national LTER networks such as SAEON in South Africa, CERN/CEOBEX in China, TERN in Australia or eLTER RI in Europe. The primary role of ILTER is currently seen as a mechanism to investigate ecosystem structure, function, and services in response to a wide range of environmental forcings using long-term, place-based research. We suggest four main fields of activities and advancements for the next decade through development/delivery of a: (1) Global multi-disciplinary community of researchers and research institutes; (2) Strategic global framework and strong partnerships in ecosystem observation and research; (3) Global Research Infrastructure (GRI); and (4) a scientific knowledge factory for societally relevant information on sustainable use of natural resources.
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Affiliation(s)
- M Mirtl
- Environment Agency Austria, Spittelauer Lände 5, 1090 Wien, Austria; Helmholtz Centre for Environmental Research - UFZ, Department of Community Ecology, Theodor-Lieser-Strasse 4, D-06120 Halle, Germany.
| | - E T Borer
- Department of Ecology, Evolution, and Behavior, 1987 Upper Buford Circle, Suite 100, University of Minnesota, St. Paul, MN 55108, USA
| | - I Djukic
- Environment Agency Austria, Spittelauer Lände 5, 1090 Wien, Austria
| | - M Forsius
- Finnish Environment Institute SYKE, P.O.Box 140, FI-00251 Helsinki, Finland
| | - H Haubold
- Environment Agency Austria, Spittelauer Lände 5, 1090 Wien, Austria
| | - W Hugo
- South African Environmental Observation Network (SAEON) of the National Research Foundation (NRF), 41 De Havilland Crescent, The Woods, Persequor Park, PO Box 2600, Pretoria 0001, South Africa
| | - J Jourdan
- Senckenberg Research Institute and Natural History Museum Frankfurt, Department of River Ecology and Conservation, Clamecystraße 12, 63571 Gelnhausen, Germany
| | - D Lindenmayer
- Fenner School of Environment and Society, Frank Fenner Building (Bldg 141), The ANU College of Medicine, Biology & Environment, The Australian National University, Acton, ACT 2601, Australia
| | - W H McDowell
- Department of Natural Resources and the Environment, University of New Hampshire, Rudman Hall, 46 College Road, Durham, NH 03824, USA
| | - H Muraoka
- River Basin Research Center, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - D E Orenstein
- Faculty of Architecture and Town Planning, Technion - Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - J C Pauw
- South African Environmental Observation Network (SAEON) of the National Research Foundation (NRF), 41 De Havilland Crescent, The Woods, Persequor Park, PO Box 2600, Pretoria 0001, South Africa
| | - J Peterseil
- Environment Agency Austria, Spittelauer Lände 5, 1090 Wien, Austria
| | - H Shibata
- Field Science Center for Northern Biosphere, Hokkaido University, N9 W9, Kita-ku, Sapporo 060-0809, Japan
| | - C Wohner
- Environment Agency Austria, Spittelauer Lände 5, 1090 Wien, Austria
| | - X Yu
- Chinese Ecosystem Research Network (CERN), Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 11A Datun Road, Chaoyang District, Beijing 100101, China
| | - P Haase
- Senckenberg Research Institute and Natural History Museum Frankfurt, Department of River Ecology and Conservation, Clamecystraße 12, 63571 Gelnhausen, Germany; Faculty of Biology, University of Duisburg-Essen, 45141 Essen, Germany
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6
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Lamouille S, Smyth JW, O'Rourke L, Kanabur P, Guo S, Jourdan J, Sheng Z, Gourdie RG. Abstract 4765: Targeting glioblastoma cancer stem cells with a novel Connexin43 mimetic peptide. Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-4765] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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
Abstract
Glioblastoma (GBM) is a highly malignant and lethal cancer of the central nervous system. Despite intensive research efforts, there has been limited progress in improving patient outcome. The current therapy for GBM patients includes surgical resection, radiotherapy and cytotoxic chemotherapy with temozolomide (TMZ), conferring a median survival time of only 14.6 months. Failure to generate more effective treatment strategies is due in part to the cellular heterogeneity within GBM tumors, which comprise a sub-population of GBM cancer stem cells (GSCs) characterized by self-renewal characteristics and resistance to TMZ. Recent work, including our own, has demonstrated that levels of the gap junction protein Connexin43 (Cx43) correlate with GBM TMZ resistance. Increased Cx43 levels occur in GSCs compared to parental GBM cells, and patients with high levels of Cx43 mRNA and low levels of MGMT, an enzyme that repairs TMZ-induced DNA lesions, have a significantly shorter life span. In contrast, Cx43 has also been associated with anti-proliferative effects in glioma and reduced levels of Cx43 protein are reported in high-grade gliomas. In addition to forming gap junctions, Cx43 can regulate cell proliferation, migration, and apoptosis, through distinct channel-independent mechanisms. Therefore, altering the localization and/or activity of Cx43 rather than Cx43 expression alone may represent a more targeted strategy in GBM treatment. Using super-resolution microscopy, we find intracellular Cx43 decorating microtubules in GSCs demonstrating for the first time such clustering in situ. Regulation of Cx43 function is primarily associated with multiple sites for post-translational modification and protein-protein interaction within the Cx43 carboxy-terminus (CT) which includes a tubulin binding domain. We have developed a peptide named JM2 (juxtamembrane 2) composed of the Cx43 CT amino acids encompassing the microtubule-binding sequence fused to an antennapedia cell penetration domain for cellular uptake. Super-resolution microscopy and biochemical analysis confirm JM2 specific interaction with microtubules concomitantly with a loss of Cx43 interaction with microtubules in GSCs derived from patient tumors. In addition, we observe that JM2 decreases Cx43 gap junction plaque formation and cell-cell communication in GSCs and limits microtubule dynamics. Importantly, JM2 decreases cell survival in TMZ-resistant GSCs and GSC neurosphere formation in vitro, and GSC-derived tumor growth in vivo. Our current research includes the development of JM2-loaded biodegradable nanoparticles for sustained JM2 delivery in preparation for future clinical trials. In conclusion, we have developed a Cx43 mimetic peptide that significantly decreases the tumorigenic potential of GSCs and represents a novel and potent therapeutic opportunity to alter Cx43 activity in targeting chemoresistant GSCs for GBM treatment.
Citation Format: Samy Lamouille, James W. Smyth, Laurie O'Rourke, Pratik Kanabur, Sujuan Guo, Jane Jourdan, Zhi Sheng, Robert G. Gourdie. Targeting glioblastoma cancer stem cells with a novel Connexin43 mimetic peptide [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4765. doi:10.1158/1538-7445.AM2017-4765
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Affiliation(s)
| | | | | | | | - Sujuan Guo
- 1Virginia Tech Carilion Research Institute, Roanoke, VA
| | - Jane Jourdan
- 1Virginia Tech Carilion Research Institute, Roanoke, VA
| | - Zhi Sheng
- 1Virginia Tech Carilion Research Institute, Roanoke, VA
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7
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Duclos A, Peix JL, Piriou V, Occelli P, Denis A, Bourdy S, Carty MJ, Gawande AA, Debouck F, Vacca C, Lifante JC, Colin C, Aegerter P, Aouifi A, Arickx D, Aubart F, Baudrin D, Berry WR, Beuvry C, Bonnet F, Bouveret L, Cabarrot P, Cames E, Carty MJ, Caton J, Chenitz MC, Clergues F, Colin C, Coudray JM, Damiens M, Dauzac C, Debono B, Debouck F, De Germay B, Deleforterie AC, Denis A, Desrousseaux JF, Didelot MP, Doat B, Domingo-Saidji NY, Duclos A, Durieux P, Fessy M, Hardy P, Cariven P, Fontas N, Ganansia P, Gawande AA, Giraud F, Gostiaux G, Habi S, Haga S, Houlgatte A, Jaffe M, Jourdan J, Kaczmarek N, Lamblin S, Level C, Liaras E, Lifante JC, Lipsitz SR, Majchrzak C, Malavaud B, Serres TM, Martin X, Martinet C, Maupetit B, Michel P, Movondo A, Naamani B, Nacry R, Occelli P, Olousouzian S, Papin P, Paquet JC, Parfaite A, Pattou F, Paugam C, Pavy E, Peix JL, Petit H, Pierre S, Piriou V, Poupon Bourdy S, Pradere B, Quesne M, Radola Y, Raould A, Rongieras F, Rouquette I, Sanders V, Sanz F, Sens F, Surmont S, Sicre C, Tabur D, Targosz P, Thery D, Toppan N, Usandizaga G, Vacca C, Verheyde I, Zadegan F. Cluster randomized trial to evaluate the impact of team training on surgical outcomes. Br J Surg 2016; 103:1804-1814. [DOI: 10.1002/bjs.10295] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 05/07/2016] [Accepted: 07/15/2016] [Indexed: 11/10/2022]
Abstract
Abstract
Background
The application of safety principles from the aviation industry to the operating room has offered hope in reducing surgical complications. This study aimed to assess the impact on major surgical complications of adding an aviation-based team training programme after checklist implementation.
Methods
A prospective parallel-group cluster trial was undertaken between September 2011 and March 2013. Operating room teams from 31 hospitals were assigned randomly to participate in a team training programme focused on major concepts of crew resource management and checklist utilization. The primary outcome measure was the occurrence of any major adverse event, including death, during the hospital stay within the first 30 days after surgery. Using a difference-in-difference approach, the ratio of the odds ratios (ROR) was estimated to compare changes in surgical outcomes between intervention and control hospitals.
Results
Some 22 779 patients were enrolled, including 5934 before and 16 845 after team training implementation. The risk of major adverse events fell from 8·8 to 5·5 per cent in 16 intervention hospitals (adjusted odds ratio 0·57, 95 per cent c.i. 0·48 to 0·68; P < 0·001) and from 7·9 to 5·4 per cent in 15 control hospitals (odds ratio 0·64, 0·50 to 0·81; P < 0·001), resulting in the absence of difference between arms (ROR 0·90, 95 per cent c.i. 0·67 to 1·21; P = 0·474). Outcome trends revealed significant improvements among ten institutions, equally distributed across intervention and control hospitals.
Conclusion
Surgical outcomes improved substantially, with no difference between trial arms. Successful implementation of an aviation-based team training programme appears to require modification and adaptation of its principles in the context of the the surgical milieu. Registration number: NCT01384474 (http://www.clinicaltrials.gov).
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Affiliation(s)
- A Duclos
- Pôle Information Médicale Evaluation Recherche, Hospices Civils de Lyon, Lyon, France
- Health Services and Performance Research Laboratory, Université Claude Bernard Lyon 1, EA, 7425, Lyon, France
- Center for Surgery and Public Health, Brigham and Women's Hospital – Harvard Medical School, Boston, Massachusetts, USA
| | - J L Peix
- Service de Chirurgie Générale et Endocrinienne, Pierre Bénite, France
| | - V Piriou
- Health Services and Performance Research Laboratory, Université Claude Bernard Lyon 1, EA, 7425, Lyon, France
- Service d'Anesthésie Réanimation Médicale et Chirurgicale, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, Pierre Bénite, France
| | - P Occelli
- Pôle Information Médicale Evaluation Recherche, Hospices Civils de Lyon, Lyon, France
- Health Services and Performance Research Laboratory, Université Claude Bernard Lyon 1, EA, 7425, Lyon, France
| | - A Denis
- Pôle Information Médicale Evaluation Recherche, Hospices Civils de Lyon, Lyon, France
| | - S Bourdy
- Pôle Information Médicale Evaluation Recherche, Hospices Civils de Lyon, Lyon, France
| | - M J Carty
- Center for Surgery and Public Health, Brigham and Women's Hospital – Harvard Medical School, Boston, Massachusetts, USA
| | - A A Gawande
- Center for Surgery and Public Health, Brigham and Women's Hospital – Harvard Medical School, Boston, Massachusetts, USA
- Ariadne Labs and Harvard Chan School of Public Health, Boston, Massachusetts, USA
| | - F Debouck
- Air France Consulting, AFM42, Chambourcy, France
| | - C Vacca
- Coordination pour l'Evaluation des Pratiques Professionnelles en Santé en Rhône-Alpes, Lyon, France
| | - J C Lifante
- Health Services and Performance Research Laboratory, Université Claude Bernard Lyon 1, EA, 7425, Lyon, France
- Service de Chirurgie Générale et Endocrinienne, Pierre Bénite, France
| | - C Colin
- Pôle Information Médicale Evaluation Recherche, Hospices Civils de Lyon, Lyon, France
- Health Services and Performance Research Laboratory, Université Claude Bernard Lyon 1, EA, 7425, Lyon, France
| | | | | | | | | | - D Baudrin
- Agence Régional de Santé de Toulouse
| | | | | | - F Bonnet
- Assistance Publique-Hôpitaux de Paris
| | | | | | - E Cames
- Centre Hospitalier Universitaire de Toulouse
| | - M J Carty
- Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - J Caton
- Clinique Emile Vialar de Lyon
| | | | | | | | | | | | - C Dauzac
- Assistance Publique-Hôpitaux de Paris
| | - B Debono
- Clinique des Cèdres de Cornebarrieu
| | | | | | | | | | | | | | | | | | | | - P Durieux
- Assistance Publique-Hôpitaux de Paris
| | | | - P Hardy
- Assistance Publique-Hôpitaux de Paris
| | | | - N Fontas
- Centre Hospitalier Universitaire de Toulouse
| | | | - A A Gawande
- Brigham and Women's Hospital, Boston, Massachusetts, USA
| | | | | | - S Habi
- Centre Hospitalier de Vienne
| | - S Haga
- Infirmerie Protestante de Lyon
| | - A Houlgatte
- Hôpital d'Instruction des Armées du Val de Grâce
| | - M Jaffe
- Clinique Ambroise Paré de Toulouse
| | | | | | | | - C Level
- Assistance Publique-Hôpitaux de Paris
| | - E Liaras
- Hôpital Privé de Natécia de Lyon
| | | | - S R Lipsitz
- Brigham and Women's Hospital, Boston, Massachusetts, USA
| | | | - B Malavaud
- Centre Hospitalier Régional Universitaire de Toulouse
| | | | | | | | | | | | | | | | | | | | | | - P Papin
- Centre Hospitalier de Villefranche sur Saône
| | | | | | - F Pattou
- Centre Hospitalier Régional Universitaire de Lille
| | - C Paugam
- Assistance Publique-Hôpitaux de Paris
| | - E Pavy
- Hôpital Simone Veil d'Eaubonne
| | | | | | - S Pierre
- Institut Claudius Régaud de Toulouse
| | | | | | - B Pradere
- Centre Hospitalier Régional Universitaire de Lille
| | | | - Y Radola
- Centre Hospitalier Régional Universitaire de Lille
| | - A Raould
- Assistance Publique-Hôpitaux de Paris
| | - F Rongieras
- Hôpital d'Instruction des Armées Desgenettes de Lyon
| | | | - V Sanders
- Centre Hospitalier Régional Universitaire de Lille
| | - F Sanz
- Centre Hospitalier Régional Universitaire de Lille
| | | | | | | | | | | | - D Thery
- Institut Catholique de Lille
| | - N Toppan
- Clinique de l'Union de Saint Jean
| | | | - C Vacca
- Coordination pour l'Evaluation des Pratiques Professionnelles en Santé en Rhône-Alpes de Lyon
| | | | - F Zadegan
- Assistance Publique-Hôpitaux de Paris
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Murphy SF, Varghese RT, Lamouille S, Guo S, Pridham KJ, Kanabur P, Osimani AM, Sharma S, Jourdan J, Rodgers CM, Simonds GR, Gourdie RG, Sheng Z. Connexin 43 Inhibition Sensitizes Chemoresistant Glioblastoma Cells to Temozolomide. Cancer Res 2015; 76:139-49. [PMID: 26542214 DOI: 10.1158/0008-5472.can-15-1286] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 10/04/2015] [Indexed: 01/24/2023]
Abstract
Resistance of glioblastoma (GBM) to the front-line chemotherapeutic agent temozolomide (TMZ) continues to challenge GBM treatment efforts. The repair of TMZ-induced DNA damage by O-6-methylguanine-DNA methyltransferase (MGMT) confers one mechanism of TMZ resistance. Paradoxically, MGMT-deficient GBM patients survive longer despite still developing resistance to TMZ. Recent studies indicate that the gap junction protein connexin 43 (Cx43) renders GBM cells resistant to TMZ through its carboxyl terminus (CT). In this study, we report insights into how Cx43 promotes TMZ resistance. Cx43 levels were inversely correlated with TMZ sensitivity of GBM cells, including GBM stem cells. Moreover, Cx43 levels inversely correlated with patient survival, including as observed in MGMT-deficient GBM patients. Addition of the C-terminal peptide mimetic αCT1, a selective inhibitor of Cx43 channels, sensitized human MGMT-deficient and TMZ-resistant GBM cells to TMZ treatment. Moreover, combining αCT1 with TMZ-blocked AKT/mTOR signaling, induced autophagy and apoptosis in TMZ-resistant GBM cells. Our findings suggest that Cx43 may offer a biomarker to predict the survival of patients with MGMT-independent TMZ resistance and that combining a Cx43 inhibitor with TMZ could enhance therapeutic responses in GBM, and perhaps other TMZ-resistant cancers.
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Affiliation(s)
- Susan F Murphy
- Virginia Tech Carilion Research Institute, Roanoke, Virginia
| | | | - Samy Lamouille
- Virginia Tech Carilion Research Institute, Roanoke, Virginia. FirstString Research Inc., Mount Pleasant, South Carolina
| | - Sujuan Guo
- Virginia Tech Carilion Research Institute, Roanoke, Virginia
| | - Kevin J Pridham
- Virginia Tech Carilion Research Institute, Roanoke, Virginia
| | - Pratik Kanabur
- Virginia Tech Carilion Research Institute, Roanoke, Virginia
| | | | - Shaan Sharma
- Virginia Tech Carilion Research Institute, Roanoke, Virginia
| | - Jane Jourdan
- Virginia Tech Carilion Research Institute, Roanoke, Virginia
| | - Cara M Rodgers
- Department of Neurosurgery, Carilion Clinic, Roanoke, Virginia
| | - Gary R Simonds
- Department of Neurosurgery, Carilion Clinic, Roanoke, Virginia
| | - Robert G Gourdie
- Virginia Tech Carilion Research Institute, Roanoke, Virginia. Faculty of Health Science, Virginia Tech, Blacksburg, Virginia. Virginia Tech-Wake Forest University School of Biomedical Engineering and Sciences, Blacksburg, Virginia. Department of Emergency Medicine, Virginia Tech Carilion School of Medicine, Roanoke, Virginia.
| | - Zhi Sheng
- Virginia Tech Carilion Research Institute, Roanoke, Virginia. Faculty of Health Science, Virginia Tech, Blacksburg, Virginia. Department of Biological Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia. Department of Internal Medicine, Virginia Tech Carilion School of Medicine, Roanoke, Virginia.
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9
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Al-Mamari SA, Jourdan J, Boukaidi S, Quintens H, Marsaud A, Carpentier X, Arnaud P, Mentine N, Durand M, Amiel J, Chevallier D. [Ipsilateral dual kidney transplantation: a monocentric experience about 15 cases and literature review]. Prog Urol 2014; 24:87-93. [PMID: 24485077 DOI: 10.1016/j.purol.2013.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [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: 03/02/2013] [Revised: 08/01/2013] [Accepted: 09/09/2013] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Our study aimed to support the viability of the concept of Ipsilateral Dual Kidney Transplantation (DKT) by presenting our initial experience and proposing a review of the literature in this subject. METHODS Fifteen ipsilateral DKT were performed at Nice University Hospital between August 2010 and March 2012. We have described our skin incision preferences, the vascular anastomoses, and the uretero-vesical reimplantation. We have analyzed the operative duration, the cold ischemia time (CIT) of both transplants, the blood transfusion volume, the intraoperative and postoperative complications, the time to diuresis recovery, the hospital stay, and the kinetics of the creatinine clearance until the third postoperative month. We have compared our results with those of the literature. RESULTS The average CIT of the first transplant (T1) was 17.5 ± 3.3 hours, and that of the second (T2) was 18.4 ± 3.3 hours. The mean operating time was 234 ± 67 minutes. Patients received an average of 2 units of blood during surgery [0-4] and 1.8 units in the postoperative period [0-15]. The complications rate was 26.7% and included an intraoperative T2 artery thrombosis and 3 postoperative complications consistent with a hematoma, a T2 ureteric necrosis and a T2 venous thrombosis. Two transplants were lost (6.7%) and one death (6.7%) was reported on day 40. The average length of hospital stay was 20.9 ± 7.8 days. The mean creatinine clearance values were 12.6 mL/min at D2, 35.6 mL/min at D7, 44.9 mL/min on discharge, and 48.2 mL/min at D90. CONCLUSION Our results supported the viability of the dual kidney transplantation concept. Furthermore the ipsilateral approach shortened the procedure and limited the surgical trauma by preserving the contralateral iliac fossa, without compromising renal function recovery or increasing morbidity.
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Affiliation(s)
- S A Al-Mamari
- Service d'urologie, hôpital l'Archet 2, CHU de Nice, 151, route Saint-Antoine-de-Ginestière, BP 06202, 23079 Nice cedex 3, France.
| | - J Jourdan
- Service d'urologie, hôpital l'Archet 2, CHU de Nice, 151, route Saint-Antoine-de-Ginestière, BP 06202, 23079 Nice cedex 3, France
| | - S Boukaidi
- Service d'urologie, hôpital l'Archet 2, CHU de Nice, 151, route Saint-Antoine-de-Ginestière, BP 06202, 23079 Nice cedex 3, France
| | - H Quintens
- Service d'urologie, hôpital l'Archet 2, CHU de Nice, 151, route Saint-Antoine-de-Ginestière, BP 06202, 23079 Nice cedex 3, France
| | - A Marsaud
- Service d'urologie, hôpital l'Archet 2, CHU de Nice, 151, route Saint-Antoine-de-Ginestière, BP 06202, 23079 Nice cedex 3, France
| | - X Carpentier
- Service d'urologie, hôpital l'Archet 2, CHU de Nice, 151, route Saint-Antoine-de-Ginestière, BP 06202, 23079 Nice cedex 3, France
| | - P Arnaud
- Service d'urologie, hôpital l'Archet 2, CHU de Nice, 151, route Saint-Antoine-de-Ginestière, BP 06202, 23079 Nice cedex 3, France
| | - N Mentine
- Service d'urologie, hôpital l'Archet 2, CHU de Nice, 151, route Saint-Antoine-de-Ginestière, BP 06202, 23079 Nice cedex 3, France
| | - M Durand
- Service d'urologie, hôpital l'Archet 2, CHU de Nice, 151, route Saint-Antoine-de-Ginestière, BP 06202, 23079 Nice cedex 3, France
| | - J Amiel
- Service d'urologie, hôpital l'Archet 2, CHU de Nice, 151, route Saint-Antoine-de-Ginestière, BP 06202, 23079 Nice cedex 3, France
| | - D Chevallier
- Service d'urologie, hôpital l'Archet 2, CHU de Nice, 151, route Saint-Antoine-de-Ginestière, BP 06202, 23079 Nice cedex 3, France
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Ahl-Manary S, Jourdan J, Carpentier X, Arnaud P, Mentine N, Durand M, Quintens H, Boukaidi S, Marsaud A, Chevallier D, Amiel J. Bi-transplantation rénale par abord ipsilatéral : expérience d’un centre à propos de 15 patients opérés consécutivement et revue de la littérature. Prog Urol 2012. [DOI: 10.1016/j.purol.2012.08.081] [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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11
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Rhett JM, Ongstad EL, Jourdan J, Gourdie RG. Cx43 associates with Na(v)1.5 in the cardiomyocyte perinexus. J Membr Biol 2012; 245:411-22. [PMID: 22811280 DOI: 10.1007/s00232-012-9465-z] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [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] [Received: 04/10/2012] [Accepted: 06/20/2012] [Indexed: 01/24/2023]
Abstract
Gap junctions (GJs) are aggregates of channels that provide for direct cytoplasmic connection between cells. Importantly, this connection is thought responsible for cell-to-cell transfer of the cardiac action potential. The GJ channels of ventricular myocytes are composed of connexin43 (Cx43). Interaction of Cx43 with zonula occludens-1 (ZO-1) is localized not only at the GJ plaque, but also to the region surrounding the GJ, the perinexus. Cx43 in the perinexus is not detectable by immunofluorescence, yet localization of Cx43/ZO-1 interaction to this region indicated the presence of Cx43. Therefore, we hypothesized that Cx43 occurs in the perinexus at a lower concentration per unit membrane than in the GJ itself, making it difficult to visualize. To overcome this, the Duolink protein-protein interaction assay was used to detect Cx43. Duolink labeling of cardiomyocytes localized Cx43 to the perinexus. Quantification demonstrated that signal in the perinexus was lower than in the GJ but significantly higher than in nonjunctional regions. Additionally, Duolink of Triton X-100-extracted cultures suggested that perinexal Cx43 is nonjunctional. Importantly, the voltage gated sodium channel Na(v)1.5, which is responsible for initiation of the action potential, was found to interact with perinexal Cx43 but not with ZO-1. This work provides a detailed characterization of the structure of the perinexus at the GJ edge and indicates that one of its potential functions in the heart may be in facilitating conduction of action potential.
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Affiliation(s)
- J Matthew Rhett
- Department of Regenerative Medicine, Medical University of South Carolina, 173 Ashley Ave, CRI Room 616, Charleston, SC 29425, USA
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12
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Fomin N, Arrington J, Asaturyan R, Benmokhtar F, Boeglin W, Bosted P, Bruell A, Bukhari MHS, Christy ME, Chudakov E, Clasie B, Connell SH, Dalton MM, Daniel A, Day DB, Dutta D, Ent R, El Fassi L, Fenker H, Filippone BW, Garrow K, Gaskell D, Hill C, Holt RJ, Horn T, Jones MK, Jourdan J, Kalantarians N, Keppel CE, Kiselev D, Kotulla M, Lindgren R, Lung AF, Malace S, Markowitz P, McKee P, Meekins DG, Mkrtchyan H, Navasardyan T, Niculescu G, Opper AK, Perdrisat C, Potterveld DH, Punjabi V, Qian X, Reimer PE, Roche J, Rodriguez VM, Rondon O, Schulte E, Seely J, Segbefia E, Slifer K, Smith GR, Solvignon P, Tadevosyan V, Tajima S, Tang L, Testa G, Trojer R, Tvaskis V, Vulcan WF, Wasko C, Wesselmann FR, Wood SA, Wright J, Zheng X. New measurements of high-momentum nucleons and short-range structures in nuclei. Phys Rev Lett 2012; 108:092502. [PMID: 22463628 DOI: 10.1103/physrevlett.108.092502] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Indexed: 05/31/2023]
Abstract
We present new measurements of electron scattering from high-momentum nucleons in nuclei. These data allow an improved determination of the strength of two-nucleon correlations for several nuclei, including light nuclei where clustering effects can, for the first time, be examined. The data also include the kinematic region where three-nucleon correlations are expected to dominate.
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Affiliation(s)
- N Fomin
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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13
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Jeribi A, Berguignat M, Carpentier X, Jourdan J, Cassuto-Viguier E, Albano L. NGAL et Cystatine C : 2 biomarqueurs plasmatiques précoces, prédictifs de la reprise de fonction en transplantation rénale. Nephrol Ther 2011. [DOI: 10.1016/j.nephro.2011.07.270] [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: 12/01/2022]
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14
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Antonov A, Gaidarov M, Ivanov M, Kadrev D, Aïche M, Barreau G, Czajkowski S, Jurado B, Belier G, Chatillon A, Granier T, Taieb J, Doré D, Letourneau A, Ridikas D, Dupont E, Berthoumieux E, Panebianco S, Farget F, Schmitt C, Audouin L, Khan E, Tassan-Got L, Aumann T, Beller P, Boretzky K, Dolinskii A, Egelhof P, Emling H, Franzke B, Geissel H, Kelic-Heil A, Kester O, Kurz N, Litvinov Y, Münzenberg G, Nolden F, Schmidt KH, Scheidenberger C, Simon H, Steck M, Weick H, Enders J, Pietralla N, Richter A, Schrieder G, Zilges A, Distler M, Merkel H, Müller U, Junghans A, Lenske H, Fujiwara M, Suda T, Kato S, Adachi T, Hamieh S, Harakeh M, Kalantar-Nayestanaki N, Wörtche H, Berg G, Koop I, Logatchov P, Otboev A, Parkhomchuk V, Shatilov D, Shatunov P, Shatunov Y, Shiyankov S, Shvartz D, Skrinsky A, Chulkov L, Danilin B, Korsheninnikov A, Kuzmin E, Ogloblin A, Volkov V, Grishkin Y, Lisin V, Mushkarenkov A, Nedorezov V, Polonski A, Rudnev N, Turinge A, Artukh A, Avdeichikov V, Ershov S, Fomichev A, Golovkov M, Gorshkov A, Grigorenko L, Klygin S, Krupko S, Meshkov I, Rodin A, Sereda Y, Seleznev I, Sidorchuk S, Syresin E, Stepantsov S, Ter-Akopian G, Teterev Y, Vorontsov A, Kamerdzhiev S, Litvinova E, Karataglidis S, Alvarez Rodriguez R, Borge M, Fernandez Ramirez C, Garrido E, Sarriguren P, Vignote J, Fraile Prieto L, Lopez Herraiz J, Moya de Guerra E, Udias-Moinelo J, Amaro Soriano J, Lallena Rojo A, Caballero J, Johansson H, Jonson B, Nilsson T, Nyman G, Zhukov M, Golubev P, Rudolph D, Hencken K, Jourdan J, Krusche B, Rauscher T, Kiselev D, Trautmann D, Al-Khalili J, Catford W, Johnson R, Stevenson P, Barton C, Jenkins D, Lemmon R, Chartier M, Cullen D, Bertulani C, Heinz A. The electron–ion scattering experiment ELISe at the International Facility for Antiproton and Ion Research (FAIR)—A conceptual design study. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 2011. [DOI: 10.1016/j.nima.2010.12.246] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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15
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Abstract
Cx43 gap junctions (GJs) are integral to the function of the mammalian heart. It is shown that ZO-1 dynamically regulates the transition between Cx43 connexons and GJ intercellular channels, determining the balance of connexon-mediated cell permeability to GJ communication. Importantly, a novel domain proximal to GJs is identified—the perinexus. Connexin 43 (Cx43) is a gap junction (GJ) protein widely expressed in mammalian tissues that mediates cell-to-cell coupling. Intercellular channels comprising GJ aggregates form from docking of paired connexons, with one each contributed by apposing cells. Zonula occludens-1 (ZO-1) binds the carboxy terminus of Cx43, and we have previously shown that inhibition of the Cx43/ZO-1 interaction increases GJ size by 48 h. Here we demonstrated that increases in GJ aggregation occur within 2 h (∼Cx43 half-life) following disruption of Cx43/ZO-1. Immunoprecipitation and Duolink protein–protein interaction assays indicated that inhibition targets ZO-1 binding with Cx43 in GJs as well as connexons in an adjacent domain that we term the “perinexus.” Consistent with GJ size increases being matched by decreases in connexons, inhibition of Cx43/ZO-1 reduced the extent of perinexal interaction, increased the proportion of connexons docked in GJs relative to undocked connexons in the plasma membrane, and increased GJ intercellular communication while concomitantly decreasing hemichannel-mediated membrane permeance in contacting, but not noncontacting, cells. ZO-1 small interfering RNA and overexpression experiments verified that loss and gain of ZO-1 function govern the transition of connexons into GJs. It is concluded that ZO-1 regulates the rate of undocked connexon aggregation into GJs, enabling dynamic partitioning of Cx43 channel function between junctional and proximal nonjunctional domains of plasma membrane.
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Affiliation(s)
- J Matthew Rhett
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC 29425, USA
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16
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Palatinus JA, O'Quinn MP, Barker RJ, Harris BS, Jourdan J, Gourdie RG. ZO-1 determines adherens and gap junction localization at intercalated disks. Am J Physiol Heart Circ Physiol 2010; 300:H583-94. [PMID: 21131473 DOI: 10.1152/ajpheart.00999.2010] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The disruption of the spatial order of electromechanical junctions at myocyte-intercalated disks (ICDs) is a poorly understood characteristic of many cardiac disease states. Here, in vitro and in vivo evidence is provided that zonula occludens-1 (ZO-1) regulates the organization of gap junctions (GJs) and adherens junctions (AJs) at ICDs. We investigated the contribution of ZO-1 to cell-cell junction localization by expressing a dominant-negative ZO-1 construct (DN-ZO-1) in rat ventricular myocytes (VMs). The expression of DN-ZO-1 in cultured neonatal VMs for 72 h reduced the interaction of ZO-1 and N-cadherin, as assayed by colocalization and coimmunoprecipitation, prompting cytoplasmic internalization of AJ and GJ proteins. DN-ZO-1 expression in adult VMs in vivo also reduced N-cadherin colocalization with ZO-1, a phenomenon not observed when the connexin-43 (Cx43)-ZO-1 interaction was disrupted using a mimetic of the ZO-1-binding ligand from Cx43. DN-ZO-1-infected VMs demonstrated large GJs at the ICD periphery and showed a loss of focal ZO-1 concentrations along plaque edges facing the disk interior. Additionally, there was breakdown of the characteristic ICD pattern of small interior and large peripheral GJs. Continuous DN-ZO-1 expression in VMs over postnatal development reduced ICD-associated Cx43 GJs and increased lateralized and cytoplasmic Cx43. We conclude that ZO-1 regulation of GJ localization is via an association with the N-cadherin multiprotein complex and that this is a key determinant of stable localization of both AJs and GJs at the ICD.
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Affiliation(s)
- Joseph A Palatinus
- Department of Regenerative Medicine and Cell Biology, Cardiovascular Biology Center, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC, 29425, USA
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17
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Fomin N, Arrington J, Day DB, Gaskell D, Daniel A, Seely J, Asaturyan R, Benmokhtar F, Boeglin W, Boillat B, Bosted P, Bruell A, Bukhari MHS, Christy ME, Chudakov E, Clasie B, Connell SH, Dalton MM, Dutta D, Ent R, El Fassi L, Fenker H, Filippone BW, Garrow K, Hill C, Holt RJ, Horn T, Jones MK, Jourdan J, Kalantarians N, Keppel CE, Kiselev D, Kotulla M, Lindgren R, Lung AF, Malace S, Markowitz P, McKee P, Meekins DG, Miyoshi T, Mkrtchyan H, Navasardyan T, Niculescu G, Okayasu Y, Opper AK, Perdrisat C, Potterveld DH, Punjabi V, Qian X, Reimer PE, Roche J, Rodriguez VM, Rondon O, Schulte E, Segbefia E, Slifer K, Smith GR, Solvignon P, Tadevosyan V, Tajima S, Tang L, Testa G, Trojer R, Tvaskis V, Vulcan WF, Wasko C, Wesselmann FR, Wood SA, Wright J, Zheng X. Scaling of the F2 structure function in nuclei and quark distributions at x>1. Phys Rev Lett 2010; 105:212502. [PMID: 21231294 DOI: 10.1103/physrevlett.105.212502] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Indexed: 05/30/2023]
Abstract
We present new data on electron scattering from a range of nuclei taken in Hall C at Jefferson Lab. For heavy nuclei, we observe a rapid falloff in the cross section for x>1, which is sensitive to short-range contributions to the nuclear wave function, and in deep inelastic scattering corresponds to probing extremely high momentum quarks. This result agrees with higher energy muon scattering measurements, but is in sharp contrast to neutrino scattering measurements which suggested a dramatic enhancement in the distribution of the "superfast" quarks probed at x>1. The falloff at x>1 is noticeably stronger in 2H and 3He, but nearly identical for all heavier nuclei.
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Affiliation(s)
- N Fomin
- University of Virginia, Charlottesville, Virginia, USA
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Slifer K, Rondón OA, Aghalaryan A, Ahmidouch A, Asaturyan R, Bloch F, Boeglin W, Bosted P, Carasco C, Carlini R, Cha J, Chen JP, Christy ME, Cole L, Coman L, Crabb D, Danagoulian S, Day D, Dunne J, Elaasar M, Ent R, Fenker H, Frlez E, Gaskell D, Gan L, Gomez J, Hu B, Jourdan J, Jones MK, Keith C, Keppel CE, Khandaker M, Klein A, Kramer L, Liang Y, Lichtenstadt J, Lindgren R, Mack D, McKee P, McNulty D, Meekins D, Mkrtchyan H, Nasseripour R, Niculescu I, Normand K, Norum B, Pocanic D, Prok Y, Raue B, Reinhold J, Roche J, Kiselev D, Savvinov N, Sawatzky B, Seely M, Sick I, Smith C, Smith G, Stepanyan S, Tang L, Tajima S, Testa G, Vulcan W, Wang K, Warren G, Wesselmann FR, Wood S, Yan C, Yuan L, Yun J, Zeier M, Zhu H. Probing quark-gluon interactions with transverse polarized scattering. Phys Rev Lett 2010; 105:101601. [PMID: 20867509 DOI: 10.1103/physrevlett.105.101601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2009] [Revised: 08/24/2010] [Indexed: 05/29/2023]
Abstract
We have extracted QCD matrix elements from our data on doubly polarized inelastic scattering of electrons on nuclei. We find the higher twist matrix element d˜2, which arises strictly from quark-gluon interactions, to be unambiguously nonzero. The data also reveal an isospin dependence of higher twist effects if we assume that the Burkhardt-Cottingham sum rule is valid. The fundamental Bjorken sum rule obtained from the a0 matrix element is satisfied at our low momentum transfer.
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Affiliation(s)
- K Slifer
- University of Virginia, Charlottesville, Virginia 22903, USA
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Seely J, Daniel A, Gaskell D, Arrington J, Fomin N, Solvignon P, Asaturyan R, Benmokhtar F, Boeglin W, Boillat B, Bosted P, Bruell A, Bukhari MHS, Christy ME, Clasie B, Connell S, Dalton MM, Day D, Dunne J, Dutta D, El Fassi L, Ent R, Fenker H, Filippone BW, Gao H, Hill C, Holt RJ, Horn T, Hungerford E, Jones MK, Jourdan J, Kalantarians N, Keppel CE, Kiselev D, Kotulla M, Lee C, Lung AF, Malace S, Meekins DG, Mertens T, Mkrtchyan H, Navasardyan T, Niculescu G, Niculescu I, Nomura H, Okayasu Y, Opper AK, Perdrisat C, Potterveld DH, Punjabi V, Qian X, Reimer PE, Roche J, Rodriguez VM, Rondon O, Schulte E, Segbefia E, Slifer K, Smith GR, Tadevosyan V, Tajima S, Tang L, Testa G, Trojer R, Tvaskis V, Vulcan WF, Wesselmann FR, Wood SA, Wright J, Yuan L, Zheng X. New measurements of the European Muon Collaboration effect in very light nuclei. Phys Rev Lett 2009; 103:202301. [PMID: 20365978 DOI: 10.1103/physrevlett.103.202301] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Revised: 07/27/2009] [Indexed: 05/29/2023]
Abstract
New Jefferson Lab data are presented on the nuclear dependence of the inclusive cross section from (2)H, (3)He, (4)He, (9)Be and (12)C for 0.3 < x < 0.9, Q(2) approximately 3-6 GeV(2). These data represent the first measurement of the EMC effect for (3)He at large x and a significant improvement for (4)He. The data do not support previous A-dependent or density-dependent fits to the EMC effect and suggest that the nuclear dependence of the quark distributions may depend on the local nuclear environment.
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Affiliation(s)
- J Seely
- Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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Rhett JM, Jourdan J, O'Quinn M, Gourdie RG. Inhibition of Cx43/ZO‐1 Interaction Improves Gap Junction Intercellular Communication and Reduces Connexon Activity. FASEB J 2009. [DOI: 10.1096/fasebj.23.1_supplement.1028.1] [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] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Jane Jourdan
- Cell Biology and AnatomyMedical University of South CarolinaCharlestonSC
| | - Michael O'Quinn
- Cell Biology and AnatomyMedical University of South CarolinaCharlestonSC
| | - Robert G Gourdie
- Cell Biology and AnatomyMedical University of South CarolinaCharlestonSC
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Fraisse T, Brunel AS, Arnaud E, Balducchi JP, Jourdan J, de Wazières B, Sotto A. Manifestations originales au cours de la polychondrite atrophiante : à propos de quatre cas. Rev Med Interne 2008; 29:801-4. [DOI: 10.1016/j.revmed.2008.03.370] [Citation(s) in RCA: 3] [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] [Received: 08/03/2007] [Accepted: 03/29/2008] [Indexed: 01/18/2023]
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Sedmera D, Harris BS, Grant E, Zhang N, Jourdan J, Kurkova D, Gourdie RG. Cardiac expression patterns of endothelin-converting enzyme (ECE): implications for conduction system development. Dev Dyn 2008; 237:1746-53. [PMID: 18489007 DOI: 10.1002/dvdy.21572] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The spatiotemporal distribution of the endothelin-converting enzyme (ECE) protein in the embryonic chick heart and the association of this polypeptide with the developing cardiac conduction system is described here for the first time. Further, we show how cardiac hemodynamic load directly affects ECE level and distribution. Endothelin (ET) is a cytokine involved in the inductive recruitment of Purkinje fibers. ET is produced by proteolytic cleavage of Big-ET by ECE. We generated an antibody against chick ECE recognizing a single band at approximately 70 kD to correlate the cardiac expression of this protein with that reported previously for its mRNA. ECE protein expression was more widespread compared to its mRNA, being present in endothelial cells, mesenchymal cells, and myocytes, and particularly enriched in the trabeculae and nascent ventricular conduction system. The myocardial expression was significantly modified under experimentally altered hemodynamic loading. In vivo, ET receptor blockade with bosentan delayed activation sequence maturation. These data support a role for ECE in avian cardiac conduction system differentiation and maturation.
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Affiliation(s)
- David Sedmera
- Department of Cell Biology and Anatomy, Medical University of South Carolina, Charleston, South Carolina 29425, USA
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23
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Sarrau S, Jourdan J, Dupuis-Soyris F, Verwaerde P. Effects of postoperative ketamine infusion on pain control and feeding behaviour in bitches undergoing mastectomy. J Small Anim Pract 2007; 48:670-6. [PMID: 17725589 DOI: 10.1111/j.1748-5827.2007.00362.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To determine if ketamine administered to bitches at the end of a mastectomy, followed by a six-hour constant rate infusion (CRI), improved postoperative opioid analgesia and feeding behaviour. METHODS The bitches were randomised into three groups: the placebo group received 0.09 ml/kg isotonic saline intravenously followed by a six-hour CRI of 0.5 ml/kg/hour, the low-dose ketamine received 150 microg/kg ketamine intravenously followed by a six-hour CRI of 2 microg/kg/minute and the high-dose ketamine group received 700 microg/kg ketamine intravenously followed by a six-hour CRI of 10 microg/kg/minute. Any additional opioids given were recorded at the time of extubation and at intervals after extubation. Food intake was evaluated eight (T8) and 20 (T20) hours after extubation by measuring the per cent coverage of basal energy requirements (BER). RESULTS No significant difference was observed for opioid requirements between the three groups. The mean percentages of BER coverage did not differ significantly at T8 but the difference between the high-dose and low-dose ketamine groups (P=0.014), and the high-dose ketamine and placebo groups (P=0.038) was significant at T20. CLINICAL SIGNIFICANCE This study demonstrated that 700 microg/kg ketamine given intravenously postoperatively followed by a six-hour ketamine CRI of 10 microg/kg/minute improved patient feeding behaviour.
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Affiliation(s)
- S Sarrau
- National Veterinary School of Toulouse, Anaesthesia and Critical Care Unit, 23, Chemin des Capelles, 31076 Toulouse Cedex, France
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Fraisse T, Brunel A, Arnaud E, Balducchi J, Jourdan J, de Wazieres B, Sotto A. Manifestations originales au cours de la polychondrite atrophiante: à propos de quatre cas. Rev Med Interne 2007. [DOI: 10.1016/j.revmed.2007.03.287] [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: 10/23/2022]
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Gourdie RG, Ghatnekar GS, O'Quinn M, Rhett MJ, Barker RJ, Zhu C, Jourdan J, Hunter AW. The unstoppable connexin43 carboxyl-terminus: new roles in gap junction organization and wound healing. Ann N Y Acad Sci 2007; 1080:49-62. [PMID: 17132774 DOI: 10.1196/annals.1380.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [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: 11/12/2022]
Abstract
Intercellular connectivity mediated by gap junctions (GJs) composed of connexin43 (Cx43) is critical to the function of excitable tissues such as the heart and brain. Disruptions to Cx43 GJ organization are thought to be a factor in cardiac arrhythmias and are also implicated in epilepsy. This article is based on a presentation to the 4th Larry and Horti Fairberg Workshop on Interactive and Integrative Cardiology and summarizes the work of Gourdie and his lab on Cx43 GJs in the heart. Background and perspective of recently published studies on the function of Cx43-interacting protein zonula occludens-(ZO)-1 in determining the organization of GJ plaques are provided. In addition how a peptide containing a PDZ-binding sequence of Cx43, developed as part of the work on cardiac GJ organization is also described, which has led to evidence for novel and unexpected roles for Cx43 in modulating healing following tissue injury.
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Affiliation(s)
- Robert G Gourdie
- Department of Cell Biology and Anatomy, Medical University of South Carolina, Charleston, SC 29425, USA.
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26
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Sedmera D, Harris BS, Grant E, Zhang N, Jourdan J, Kurkova D, Gourdie RG. Cardiac expression patterns of endothelin‐converting enzyme (ECE) suggest a role of endothelin signaling in conduction system development. FASEB J 2007. [DOI: 10.1096/fasebj.21.5.a201] [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] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- David Sedmera
- Anatomy, First Faculty of MedicineCharles UniversityU Nemocnice 3PragueCzech Republic
- Cardiovascular MorphogenesisIAPG AS CR, Videnska 1083PragueCzech Republic
| | - Brett S. Harris
- Cell Biology and AnatomyMUSC, 173 Ashley AvenueCharlestonSC29425
| | - Elizabeth Grant
- Cell Biology and AnatomyMUSC, 173 Ashley AvenueCharlestonSC29425
| | - Ning Zhang
- Cell Biology and AnatomyMUSC, 173 Ashley AvenueCharlestonSC29425
| | - Jane Jourdan
- Cell Biology and AnatomyMUSC, 173 Ashley AvenueCharlestonSC29425
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Wesselmann FR, Slifer K, Tajima S, Aghalaryan A, Ahmidouch A, Asaturyan R, Bloch F, Boeglin W, Bosted P, Carasco C, Carlini R, Cha J, Chen JP, Christy ME, Cole L, Coman L, Crabb D, Danagoulian S, Day D, Dunne J, Elaasar M, Ent R, Fenker H, Frlez E, Gan L, Gaskell D, Gomez J, Hu B, Jones MK, Jourdan J, Keith C, Keppel CE, Khandaker M, Klein A, Kramer L, Liang Y, Lichtenstadt J, Lindgren R, Mack D, McKee P, McNulty D, Meekins D, Mkrtchyan H, Nasseripour R, Niculescu I, Normand K, Norum B, Pocanic D, Prok Y, Raue B, Reinhold J, Roche J, Rohe D, Rondón OA, Savvinov N, Sawatzky B, Seely M, Sick I, Smith C, Smith G, Stepanyan S, Tang L, Testa G, Vulcan W, Wang K, Warren G, Wood S, Yan C, Yuan L, Yun J, Zeier M, Zhu H. Proton spin structure in the resonance region. Phys Rev Lett 2007; 98:132003. [PMID: 17501192 DOI: 10.1103/physrevlett.98.132003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2006] [Indexed: 05/15/2023]
Abstract
We have examined the spin structure of the proton in the region of the nucleon resonances (1.085 GeV<W<1.910 GeV) at an average four momentum transfer of Q2=1.3 GeV2. Using the Jefferson Lab polarized electron beam, a spectrometer, and a polarized solid target, we measured the asymmetries A|| and A(perpendicular) to high precision, and extracted the asymmetries A1 and A2, and the spin structure functions g1 and g2. We found a notably nonzero A(perpendicular), significant contributions from higher-twist effects, and only weak support for polarized quark-hadron duality.
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Zhu C, Barker RJ, Hunter AW, Zhang Y, Jourdan J, Gourdie RG. Quantitative analysis of ZO-1 colocalization with Cx43 gap junction plaques in cultures of rat neonatal cardiomyocytes. Microsc Microanal 2005; 11:244-8. [PMID: 16060977 DOI: 10.1017/s143192760505049x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2004] [Accepted: 12/22/2004] [Indexed: 05/03/2023]
Abstract
The gap junction (GJ) is an aggregate of intercellular channels that facilitates cytoplasmic interchange of ions, second messengers, and other molecules of less than 1000 Da between cells. In excitable organs such as heart and brain, GJs configure extended intercellular pathways for stable and long-term propagation of action potential. In a previous study in adult rat heart, we have shown that the Drosophila disks-large related protein ZO-1 shows low to moderate colocalization at myocyte borders with the GJ protein Cx43. In the present study, we detail a protocol for characterizing the pattern and level of colocalization of ZO-1 with Cx43 in cultures of neonatal myocytes at the level of individual GJ plaques. The data indicate that ZO-1 shows on average a partial 26.6% overlap (SD = 11.3%) with Cx43 GJ plaques. There is a strong positive correlation between GJ plaque size and area of ZO-1 colocalization, indicating that the level of associated ZO-1 scales with the area of the GJ plaque. Qualitatively, the most prominent colocalization occurs at the plaque perimeter. These studies may provide insight into the presently unknown biological function of ZO-1 interaction with Cx43.
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Affiliation(s)
- Ching Zhu
- Department of Cell Biology and Anatomy, Cardiovascular Developmental Biology Center, Medical University of South Carolina, Charleston, SC 29425, USA
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Abstract
The pattern of gap junctional coupling between cells is thought to be important for the proper function of many types of tissues. At present, little is known about the molecular mechanisms that control the size and distribution of gap junctions. We addressed this issue by expressing connexin43 (Cx43) constructs in HeLa cells, a connexin-deficient cell line. HeLa cells expressing exogenously introduced wild-type Cx43 formed small, punctate gap junctions. By contrast, cells expressing Cx43-GFP formed large, sheet-like gap junctions. These results suggest that the GFP tag, which is fused to the carboxyl terminus of Cx43, alters gap junction size by masking the carboxyl terminal amino acids of Cx43 that comprise a zonula occludins-1 (ZO-1) binding site. We are currently testing this hypothesis using deletion and dominant-negative constructs that directly target the interaction between Cx43 and ZO-1.
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Affiliation(s)
- Andrew W Hunter
- Department of Cell Biology and Anatomy, Medical University of South Carolina, SC 29425, USA.
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30
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Rohe D, Armstrong CS, Asaturyan R, Baker OK, Bueltmann S, Carasco C, Day D, Ent R, Fenker HC, Garrow K, Gasparian A, Gueye P, Hauger M, Honegger A, Jourdan J, Keppel CE, Kubon G, Lindgren R, Lung A, Mack DJ, Mitchell JH, Mkrtchyan H, Mocelj D, Normand K, Petitjean T, Rondon O, Segbefia E, Sick I, Stepanyan S, Tang L, Tiefenbacher F, Vulcan WF, Warren G, Wood SA, Yuan L, Zeier M, Zhu H, Zihlmann B. Correlated strength in the nuclear spectral function. Phys Rev Lett 2004; 93:182501. [PMID: 15525158 DOI: 10.1103/physrevlett.93.182501] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2004] [Indexed: 05/24/2023]
Abstract
We have carried out an (e,e'p) experiment at high momentum transfer and in parallel kinematics to measure the strength of the nuclear spectral function S(k,E) at high nucleon momenta k and large removal energies E. This strength is related to the presence of short-range and tensor correlations, and was known hitherto only indirectly and with considerable uncertainty from the lack of strength in the independent-particle region. This experiment locates by direct measurement the correlated strength predicted by theory.
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Affiliation(s)
- D Rohe
- University of Basel, CH-4056 Basel, Switzerland
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Warren G, Wesselmann F, Zhu H, McKee P, Savvinov N, Zeier M, Aghalaryan A, Ahmidouch A, Arenhövel H, Asaturyan R, Ben-Dayan I, Bloch F, Boeglin W, Boillat B, Breuer H, Brower J, Carasco C, Carl M, Carlini R, Cha J, Chant N, Christy E, Cole L, Coman L, Coman M, Crabb D, Danagoulian S, Day D, Duek K, Dunne J, Elaasar M, Ent R, Farrell J, Fatemi R, Fawcett D, Fenker H, Forest T, Garrow K, Gasparian A, Goussev I, Gueye P, Harvey M, Hauger M, Herrera R, Hu B, Jaegle I, Jones M, Jourdan J, Keith C, Kelly J, Keppel C, Khandaker M, Klein A, Klimenko A, Kramer L, Krusche B, Kuhn S, Liang Y, Lichtenstadt J, Lindgren R, Liu J, Lung A, Mack D, Maclachlan G, Markowitz P, McNulty D, Meekins D, Mitchell J, Mkrtchyan H, Nasseripour R, Niculescu I, Normand K, Norum B, Opper A, Piasetzky E, Pierce J, Pitt M, Prok Y, Raue B, Reinhold J, Roche J, Rohe D, Rondon O, Sacker D, Sawatzky B, Seely M, Sick I, Simicevic N, Smith C, Smith G, Steinacher M, Stepanyan S, Stout J, Tadevosyan V, Tajima S, Tang L, Testa G, Trojer R, Vlahovic B, Vulcan B, Wang K, Wells S, Woehrle H, Wood S, Yan C, Yanay Y, Yuan L, Yun J, Zihlmann B. Measurement of the electric form factor of the neutron at Q2=0.5 and 1.0 GeV2/c2. Phys Rev Lett 2004; 92:042301. [PMID: 14995367 DOI: 10.1103/physrevlett.92.042301] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2003] [Indexed: 05/24/2023]
Abstract
The electric form factor of the neutron was determined from measurements of the d-->(e-->,e'n)p reaction for quasielastic kinematics. Polarized electrons were scattered off a polarized deuterated ammonia (15ND3) target in which the deuteron polarization was perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons in a large solid angle detector. We find G(n)(E)=0.0526+/-0.0033(stat)+/-0.0026(sys) and 0.0454+/-0.0054+/-0.0037 at Q(2)=0.5 and 1.0 (GeV/c)(2), respectively.
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Affiliation(s)
- G Warren
- Universität Basel, CH-4056 Basel, Switzerland
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Bond J, Sedmera D, Jourdan J, Zhang Y, Eisenberg CA, Eisenberg LM, Gourdie RG. Wnt11 and Wnt7a are up-regulated in association with differentiation of cardiac conduction cells in vitro and in vivo. Dev Dyn 2003; 227:536-43. [PMID: 12889062 DOI: 10.1002/dvdy.10333] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The heart beat is coordinated by a precisely timed sequence of action potentials propagated through cells of the conduction system. Previously, we have shown that conduction cells in the chick embryo are derived from multipotent, cardiomyogenic progenitors present in the looped, tubular heart. Moreover, analyses of heterogeneity within myocyte clones and cell birth dating have indicated that elaboration of the conduction system occurs by ongoing, localized recruitment from within this multipotent pool. In this study, we have focused on a potential role for Wnt signaling in development of the cardiac conduction system. Treatment of embryonic myocytes from chick with endothelin-1 (ET-1) has been shown to promote expression of markers of Purkinje fiber cells. By using this in vitro model, we find that Wnt11 are Wnt7a are up-regulated in association with ET-1 treatment. Moreover, in situ hybridization reveals expression, although not temporal coincidence of, Wnt11 and Wnt7a in specialized tissues in the developing heart in vivo. Specifically, whereas Wnt11 shows transient and prominent expression in central elements of the developing conduction system (e.g., the His bundle), relative increases in Wnt7a expression emerge at sites consistent with the location of peripheral conduction cells (e.g., subendocardial Purkinje fibers). The patterns of Wnt11 and Wnt7a expression observed in vitro and in the embryonic chick heart appear to be consistent with roles for these two Wnts in differentiation of cardiac conduction tissues.
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Affiliation(s)
- Jacqueline Bond
- Department of Cell Biology and Anatomy, Medical University of South Carolina, Charleston, South Carolina 29425, USA
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Hunter A, Jourdan J, Gourdie R. Fusion of GFP to the Carboxyl Terminus of Connexin43 Increases Gap Junction Size in HeLa Cells. ACTA ACUST UNITED AC 2003. [DOI: 10.1080/714040429] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Jourdan E, Topart D, Richard B, Jourdan J, Sotto A. Severe autoimmune hemolytic anemia following rituximab therapy in a patient with a lymphoproliferative disorder. Leuk Lymphoma 2003; 44:889-90. [PMID: 12802933 DOI: 10.1080/1042819021000055110] [Citation(s) in RCA: 29] [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: 10/27/2022]
Abstract
Rituximab (chimeric anti-CD20 IgG1 monoclonal antibody) is effective in the treatment of relapsed/refractory low-grade lymphomas of B-cell origin as well as in diffuse large B-cell lymphoma. Several reports also demonstrated the efficacy of rituximab for the treatment of autoimmune cytopenia, especially for cold agglutinin disease. We report the first case, to our knowledge, of rituximab-related autoimmune hemolytic anemia. The pathophysiological mechanisms remain unknown, although the drug could act through massive cytokines liberation after destruction of CD20 positive cells by rituximab.
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MESH Headings
- Anemia, Hemolytic, Autoimmune/chemically induced
- Anemia, Hemolytic, Autoimmune/etiology
- Antibodies, Monoclonal/adverse effects
- Antibodies, Monoclonal/therapeutic use
- Antibodies, Monoclonal, Murine-Derived
- Cell Transformation, Neoplastic
- Disease Progression
- Humans
- Immunoglobulin M
- Leukemia, Lymphocytic, Chronic, B-Cell/complications
- Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy
- Lymphoproliferative Disorders/complications
- Lymphoproliferative Disorders/drug therapy
- Male
- Middle Aged
- Rituximab
- Splenomegaly
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Affiliation(s)
- E Jourdan
- Service de Médecine Interne B, Hôpital Caremeau, Av du Professeur Robert Debré, F-30900 Nîmes, France.
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Jourdan E, Defez C, Topart D, Richard B, Bellabas H, Fabbro-Peray P, Jourdan J, Sotto A. Evaluation of imipenem 1.5 g daily in febrile patients with short duration neutropenia after chemotherapy for non-leukemic hematologic malignancies and solid tumors: personal experience and review of the literature. Leuk Lymphoma 2003; 44:619-26. [PMID: 12769338 DOI: 10.1080/1042819021000055309] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [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: 10/27/2022]
Abstract
Numerous studies have demonstrated efficacy of imipenem-cilastatin, 50 mg/kg/day, as first line therapy in febrile patients with neutropenia of short duration consecutive to cytostatic chemotherapy. However, only two studies used low dosage of this antibiotic as 1.5 g/day, in prospective, double blind, randomized clinical trials, in this indication. Efficacy and tolerability of imipenem-cilastatin 0.5 g three times daily IV in 30-min infusions, as first-line empiric therapy, were retrospectively evaluated in our hematological unit. From January 1996 to September 2000, 30 neutropenic patients (12 females) with 45 febrile episodes were included. Median age was 57.5 years (31-75). Twenty-four of them had lymphomas, 4 solid tumors and 2 myelomas. There were 13 clinically documented infections, (CD, 28.8%), 16 microbiologically documented infections, (MD, 35.6%) and 16 febrile episodes corresponding to fever of unknown origin, (FUO, 35.6%). The median neutrophils count on nadir (n = 44), was 67/mm3 (8-369). The median duration of neutropenia was 5 days (3-15). Bacteremia was observed in 10 patients, urinary tract infection in 3 patients. The most frequently isolated microorganism was Escherichia coli. The overall success rate of the first line therapy was 66.7%. Adverse events were observed in 11.1% of the patients without necessity to stop treatment. The MD infections showed a lower rate of success compared with CD infections and FUO. These data were in accordance with the previous studies. The importance of number of microorganisms (p = 0.007) and of infected sites (p = 0.01) appeared as prognostic factors (univariate analysis). Although imipenem-cilastatin has been used in numerous studies as empiric broad-spectrum antibiotic therapy in the treatment of febrile neutropenic cancer patients, the exact dosage of this antibiotic is still not standardized. However, utilization of this antibiotic in monotherapy at low dosage seems to us to be safe and effective as usual dosage in the antimicrobial treatment ofthe febrile patients with post chemotherapy neutropenia of short duration.
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Affiliation(s)
- E Jourdan
- Service de Médecine Interne B, Hôpital Carémeau, rue du Professeur-Debré, 30029 CHU Nîmes, France
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Pulcini C, Roth S, Bernard E, Vandenbos E, Jourdan J, Dellamonica P. [Dissecting aortic aneurysm revealed by prolonged fever]. Presse Med 2002; 31:743. [PMID: 12148352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/26/2023] Open
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37
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Meunier JP, Berkane N, Lopez S, El Ghobary T, Teboul J, Malzac B, Isetta C, Jourdan J. Traumatic aortic regurgitation: aortic valvuloplasty controlled by aortoscopy. J Heart Valve Dis 2001; 10:784-8. [PMID: 11767187] [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: 02/23/2023]
Abstract
Traumatic aortic insufficiency is a rare occurrence after blunt chest trauma, and requires surgical treatment. Aortic valve replacement has been proposed as the procedure of choice, but primary valve repair is being performed increasingly more often. In a plead for conservative surgery, we report a case of valvuloplasty that was controlled by intraoperative aortic endoscopy. When operative conditions permit aortic valve repair, this should be carried out in order to avoid aortic valve replacement and its potential complications, especially in young patients with healthy valves. Replacement is the safest treatment for complex or multiple injuries of the aortic valve, however.
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Affiliation(s)
- J P Meunier
- Department of Cardiac Surgery, Pasteur Hospital, University of Nice, France
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38
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Zhu H, Ahmidouch A, Anklin H, Arenhövel H, Armstrong C, Bernet C, Boeglin W, Breuer H, Brindza P, Brown D, Bültmann S, Carlini R, Chant N, Cowley A, Crabb D, Danagoulian S, Day DB, Eden T, Ent R, Farah Y, Fatemi R, Garrow K, Harris C, Hauger M, Honegger A, Jourdan J, Kaufmann M, Khandaker M, Kubon G, Lichtenstadt J, Lindgren R, Lourie R, Lung A, Mack D, Malik S, Markowitz P, McFarlane K, McKee P, McNulty D, Milanovich G, Mitchell J, Mkrtchyan H, Mühlbauer M, Petitjean T, Prok Y, Rohe D, Rollinde E, Rondon OA, Roos P, Sawafta R, Sick I, Smith C, Southern T, Steinacher M, Stepanyan S, Tadevosyan V, Tieulent R, Tobias A, Vulcan W, Warren G, Wöhrle H, Wood S, Yan C, Zeier M, Zhao J, Zihlmann B. Measurement of the electric form factor of the neutron through d-->(e-->,e(')n)p at Q2 = 0.5 (GeV/c)(2). Phys Rev Lett 2001; 87:081801. [PMID: 11497934 DOI: 10.1103/physrevlett.87.081801] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2001] [Indexed: 05/23/2023]
Abstract
We report the first measurement using a solid polarized target of the neutron electric form factor G(n)(E) via d-->(e-->,e(')n)p. G(n)(E) was determined from the beam-target asymmetry in the scattering of longitudinally polarized electrons from polarized deuterated ammonia ( 15ND3). The measurement was performed in Hall C at Thomas Jefferson National Accelerator Facility in quasifree kinematics with the target polarization perpendicular to the momentum transfer. The electrons were detected in a magnetic spectrometer in coincidence with neutrons in a large solid angle segmented detector. We find G(n)(E) = 0.04632+/-0.00616(stat)+/-0.00341(syst) at Q2 = 0.495 (GeV/c)(2).
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Affiliation(s)
- H Zhu
- Institute of Nuclear and Particle Physics, University of Virginia, Charlottesville, 22903, USA
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Ducreux D, Chevallier P, Perrin C, Jourdan J, Hofman P, Raffaelli C, Padovani B. Pseudomembranous aspergillus bronchitis in a double-lung transplanted patient: unusual radiographic and CT features. Eur Radiol 2001; 10:1547-9. [PMID: 11044922 DOI: 10.1007/s003300000385] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Pseudomembranous aspergillus bronchitis is considered as an early form of invasive pulmonary aspergillosis, a well-known airway infection in immunocompromised patients. Radiologic features concerning invasive aspergillosis of the airways have been reported. However, we describe here an unusual feature of invasive aspergillus bronchitis, never reported to date, observed in a double-lung transplanted patient. Chest radiograph and CT revealed significant peribronchial thickening without any parenchymal involvement.
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Affiliation(s)
- D Ducreux
- Department of Radiology, Hopital Pasteur, Nice, France
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41
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Sotto A, De Boever CM, Fabbro-Peray P, Gouby A, Sirot D, Jourdan J. Risk factors for antibiotic-resistant Escherichia coli isolated from hospitalized patients with urinary tract infections: a prospective study. J Clin Microbiol 2001; 39:438-44. [PMID: 11158087 PMCID: PMC87756 DOI: 10.1128/jcm.39.2.438-444.2001] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
From November 1998 to February 1999 we prospectively evaluated the prevalence of resistance to penicillins, cephalosporins, carbapenem, quinolones, aminoglycosides, and trimethoprim-sulfamethoxazole (SXT) in 320 Escherichia coli isolates isolated from hospitalized patients with acute urinary tract infections (UTIs). We also studied for these strains risk factors for resistance to amoxicillin-clavulanic acid (AMC), fluoroquinolones (FQs), and SXT. Resistance rates were consistent with those from major recent studies reported in the literature. Multivariate analyses selected the following factors as being significantly associated with E. coli resistance: (i) for resistance to AMC, prior (1 year) UTI (odds ratio [OR] = 2.71, P = 0.006), prior (1 year) urinary catheter (OR = 2.98, P = 0.0025), and prior (6 months) antibiotic exposure (OR = 2.68, P = 0.005); (ii) for resistance to FQs male sex (OR = 3.87, P = 0.03), with a trend toward significance for age >65 years (OR = 7.67, P = 0.06) and prior (1 year) UTI (OR = 2.98, P = 0.07); and (iii) for resistance to SXT, male sex (OR = 1.91, P = 0.046), hospitalization in an intermediate-term-care unit (OR = 2.18, P = 0.008), and prior (1 year) UTI (OR = 2.03, P = 0.03). Ours results suggest that prior UTI is a common risk factor for resistance to the different antibiotics tested. Although few studies on risk factors for E. coli resistance to antibiotics have been published, careful interpretation of their findings, taking into consideration the population, infection site, and period studied, should contribute to the formulation of a better strategy that can be used to overcome antibiotic resistance.
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Affiliation(s)
- A Sotto
- Laboratoire Universitaire de Thérapeutique, Service de Médecine Interne B, Hôpital Carémeau, Nîmes, France.
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Bernard ML, Peterson YK, Chung P, Jourdan J, Lanier SM. Selective interaction of AGS3 with G-proteins and the influence of AGS3 on the activation state of G-proteins. J Biol Chem 2001; 276:1585-93. [PMID: 11042168 DOI: 10.1074/jbc.m005291200] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
AGS3 (activator of G-protein signaling 3) was isolated in a yeast-based functional screen for receptor-independent activators of heterotrimeric G-proteins. As an initial approach to define the role of AGS3 in mammalian signal processing, we defined the AGS3 subdomains involved in G-protein interaction, its selectivity for G-proteins, and its influence on the activation state of G-protein. Immunoblot analysis with AGS3 antisera indicated expression in rat brain, the neuronal-like cell lines PC12 and NG108-15, as well as the smooth muscle cell line DDT(1)-MF2. Immunofluorescence studies and confocal imaging indicated that AGS3 was predominantly cytoplasmic and enriched in microdomains of the cell. AGS3 coimmunoprecipitated with Galpha(i3) from cell and tissue lysates, indicating that a subpopulation of AGS3 and Galpha(i) exist as a complex in the cell. The coimmunoprecipitation of AGS3 and Galpha(i) was dependent upon the conformation of Galpha(i3) (GDP GTPgammaS (guanosine 5'-3-O-(thio)triphosphate)). The regions of AGS3 that bound Galpha(i) were localized to four amino acid repeats (G-protein regulatory motif (GPR)) in the carboxyl terminus (Pro(463)-Ser(650)), each of which were capable of binding Galpha(i). AGS3-GPR domains selectively interacted with Galpha(i) in tissue and cell lysates and with purified Galpha(i)/Galpha(t). Subsequent experiments with purified Galpha(i2) and Galpha(i3) indicated that the carboxyl-terminal region containing the four GPR motifs actually bound more than one Galpha(i) subunit at the same time. The AGS3-GPR domains effectively competed with Gbetagamma for binding to Galpha(t(GDP)) and blocked GTPgammaS binding to Galpha(i1). AGS3 and related proteins provide unexpected mechanisms for coordination of G-protein signaling pathways.
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Affiliation(s)
- M L Bernard
- Department of Pharmacology, Medical University of South Carolina, Charleston, South Carolina 29403, USA
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Vergne L, Peeters M, Mpoudi-Ngole E, Bourgeois A, Liegeois F, Toure-Kane C, Mboup S, Mulanga-Kabeya C, Saman E, Jourdan J, Reynes J, Delaporte E. Genetic diversity of protease and reverse transcriptase sequences in non-subtype-B human immunodeficiency virus type 1 strains: evidence of many minor drug resistance mutations in treatment-naive patients. J Clin Microbiol 2000; 38:3919-25. [PMID: 11060045 PMCID: PMC87518 DOI: 10.1128/jcm.38.11.3919-3925.2000] [Citation(s) in RCA: 154] [Impact Index Per Article: 6.4] [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: 11/20/2022] Open
Abstract
Most human immunodeficiency virus (HIV) drug susceptibility studies have involved subtype B strains. Little information on the impact of viral diversity on natural susceptibility to antiretroviral drugs has been reported. However, the prevalence of non-subtype-B (non-B) HIV type 1 (HIV-1) strains continues to increase in industrialized countries, and antiretroviral treatments have recently become available in certain developing countries where non-B subtypes predominate. We sequenced the protease and reverse transcriptase (RT) genes of 142 HIV-1 isolates from antiretroviral-naive patients: 4 belonged to group O and 138 belonged to group M (9 subtype A, 13 subtype B, 2 subtype C, 5 subtype D, 2 subtype F1, 9 subtype F2, 4 subtype G, 5 subtype J, 2 subtype K, 3 subtype CRF01-AE, 67 subtype CRF02-AG, and 17 unclassified isolates). No major mutations associated with resistance to nucleoside reverse transcriptase inhibitors (NRTIs) or protease inhibitors were detected. Major mutations linked to resistance to non-NRTI agents were detected in all group O isolates (A98G and Y181C) and in one subtype J virus (V108I). In contrast, many accessory mutations were found, especially in the protease gene. Only 5.6% of the 142 strains, all belonging to subtype B or D, had no mutations in the protease gene. Sixty percent had one mutation, 22.5% had two mutations, 9.8% had three mutations, and 2.1% (all group O strains) had four mutations. In order of decreasing frequency, the following mutations were identified in the protease gene: M36I (86.6%), L10I/V (26%), L63P (12.6%), K20M/R (11.2%), V77I (5.6%), A71V (2.8%), L33F (0.7%), and M46I (0.7%). R211K, an accessory mutation associated with NRTI resistance, was also observed in 43.6% of the samples. Phenotypic and clinical studies are now required to determine whether multidrug-resistant viruses emerge more rapidly during antiretroviral therapy when minor resistance-conferring mutations are present before treatment initiation.
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Affiliation(s)
- L Vergne
- Laboratoire Retrovirus, IRD, Montpellier, France
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Merle De Boever C, Sotto A, Guillot B, Jourdan J. [Carbamazepine intolerance mimicking infectious mononucleosis: apropos of 3 cases]. Therapie 2000; 54:489-91. [PMID: 10667117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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Isetta C, Garaffo R, Bastian G, Jourdan J, Baudouy M, Milano G. Life-threatening 5-fluorouracil-like cardiac toxicity after treatment with 5-fluorocytosine. Clin Pharmacol Ther 2000; 67:323-5. [PMID: 10741637 DOI: 10.1067/mcp.2000.104643] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- C Isetta
- Hôpital Pasteur and Centre Antoine-Lacassagne, Nice, France
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Sotto A, Assens C, Berard M, Jourdan J, Boffa MC. Plasma thrombomodulin level is correlated with those of the soluble interleukin-2 receptor and hepatic cytolysis markers in patients with Mediterranean spotted fever. Thromb Haemost 1999; 82:1769-70. [PMID: 10613670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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Sotto A, Foulongne V, Sirot D, Jourdan J. A method using TEM-5-beta-lactamase to assay imipenem. J Antimicrob Chemother 1999; 44:851-2. [PMID: 10590293 DOI: 10.1093/jac/44.6.851-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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48
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Camous JP, Raybaud F, Jourdan J. Pseudofracture of an ICD lead. Pacing Clin Electrophysiol 1999; 22:1704. [PMID: 10598979 DOI: 10.1111/j.1540-8159.1999.tb00395.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] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A proximal pseudofracture of a Medtronic 6936 defibrillating lead adjacent to the ICD pulse generator was found on X ray. At this site, the multifilar metallic connector joins the stimulating lead before coiling around it. Conventional X ray of the abdomen does not visualize this connection. During ICD replacement, lead impedance should be routinely measured.
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Affiliation(s)
- J P Camous
- Medical Department of Cardiology Faculty of Medecine, Nice, France
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Sotto A, Guillot B, Dandurand M, Jourdan J. Exacerbation of skin mycobacterial lesions under highly active antiretroviral therapy in an HIV-infected patient. AIDS 1999; 13:1790-1. [PMID: 10509588 DOI: 10.1097/00002030-199909100-00030] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Leprince P, Fretz C, Dorent R, Boudifa A, Jourdan J, Youssoub JJ, Bors V, Nataf P, Pavie A, Gandjbakhch I. Posttransplantation cytotoxic immunoglobulin G is associated with a high rate of acute allograft dysfunctions in heart transplant recipients. Am Heart J 1999; 138:586-92. [PMID: 10467212 DOI: 10.1016/s0002-8703(99)70164-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND The significance of anti-human leukocyte antigen immunoglobin G (IgG) detected in the posttransplantation course of heart graft recipients remains unclear. METHOD Sera from 121 cardiac allograft recipients transplanted between January 1992 and December 1994 were screened for the presence of lymphocytotoxic antibodies in the first year after transplantation. Dithiothreitol was used to differentiate IgG from immunoglobulin M. RESULTS Nineteen patients (15%) had cytotoxic IgG develop, mainly during the first month after transplantation. The percentage of women was higher in this group (42% vs 15.7%; P <.05). Donor to recipient mismatches for sex, blood typing, cytomegalovirus serology, and human leukocyte antigen typing were comparable between IgG producers and nonproducers. The frequency of acute allograft dysfunction during the first year after transplantation was significantly higher among patients producing IgG (42% vs 5.9; P <.001). Most of these acute allograft dysfunctions were independent of cellular rejection lesions but were associated with a thickening of the posterior wall and the interventricular septum during the acute episode. Finally, all the patients but one recovered. Recurrences were not uncommon and, at 1 year after transplantation, the dose of cyclosporine used in patients producing IgG was significantly greater, as was the left ventricular thickness. CONCLUSION Posttransplantation cytotoxic IgG is not uncommon and appears to be associated with a high rate of acute allograft dysfunction. Development of these antibodies can be caused by a previous undetected immunization, as suggested by the higher percentage of women in the producer group. Correlation with histologic lesions of humoral rejection are discussed.
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Affiliation(s)
- P Leprince
- Department of Thoracic and Cardiovascular Surgery, La Pitié Hospital, Paris, France
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