1
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Philip S, McDermott P, Cooper E, Coates V, McCann M. Comorbid Chronic Diseases and Ventilatory Support in COVID-19 Hospitalisations. Ir Med J 2024; 117:928. [PMID: 38526316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
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2
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Yiasemidou M, Yates C, Cooper E, Goldacre R, Lindsey I. External rectal prolapse: more than meets the eye. Tech Coloproctol 2023; 27:783-785. [PMID: 37278904 DOI: 10.1007/s10151-023-02829-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 05/29/2023] [Indexed: 06/07/2023]
Affiliation(s)
- M Yiasemidou
- Pelvic Floor Unit, Department of Colorectal Surgery, Oxford University Hospitals NHS Trust, Oxford, England
| | - C Yates
- Pelvic Floor Unit, Department of Colorectal Surgery, Oxford University Hospitals NHS Trust, Oxford, England
| | - E Cooper
- Pelvic Floor Unit, Department of Colorectal Surgery, Oxford University Hospitals NHS Trust, Oxford, England
| | - R Goldacre
- Nuffield Department of Population Health, Big Data Institute, Oxford University, Oxford, England
| | - I Lindsey
- Pelvic Floor Unit, Department of Colorectal Surgery, Oxford University Hospitals NHS Trust, Oxford, England.
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3
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Guenther M, Wei Y, Stein S, D’Ippolito A, Farouq D, Moebius D, Marineau J, Cooper E, Chuaqui C, Carulli J, Olson E. CDK11 is a selective dependency in neuroblastoma harboring loss of chromosome 1p36. Eur J Cancer 2022. [DOI: 10.1016/s0959-8049(22)01046-2] [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: 11/03/2022]
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4
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Saviuk N, Chong Y, Wang P, Bermudez S, Zhao Z, Bhaskaran AA, Bowie D, Sonenberg N, Cooper E, Haghighi AP. Loss of 4E-BP converts cerebellar long-term depression to long-term potentiation. Cell Rep 2022; 39:110911. [PMID: 35675781 DOI: 10.1016/j.celrep.2022.110911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 10/31/2021] [Accepted: 05/12/2022] [Indexed: 11/17/2022] Open
Abstract
Genetic perturbances in translational regulation result in defects in cerebellar motor learning; however, little is known about the role of translational mechanisms in the regulation of cerebellar plasticity. We show that genetic removal of 4E-BP, a translational suppressor and target of mammalian target of rapamycin complex 1, results in a striking change in cerebellar synaptic plasticity. We find that cerebellar long-term depression (LTD) at parallel fiber-Purkinje cell synapses is converted to long-term potentiation in 4E-BP knockout mice. Biochemical and pharmacological experiments suggest that increased phosphatase activity largely accounts for the defects in LTD. Our results point to a model in which translational regulation through the action of 4E-BP plays a critical role in establishing the appropriate kinase/phosphatase balance required for normal synaptic plasticity in the cerebellum.
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Affiliation(s)
- Natasha Saviuk
- Integrated Program in Neuroscience, McGill University, Montréal, QC, Canada; Department of Physiology, McGill University, Montréal, QC, Canada
| | - Yumaine Chong
- Integrated Program in Neuroscience, McGill University, Montréal, QC, Canada; Department of Physiology, McGill University, Montréal, QC, Canada
| | - Peng Wang
- Biochemistry, McGill University, Montréal, QC, Canada
| | - Sara Bermudez
- Biochemistry, McGill University, Montréal, QC, Canada
| | - Zhe Zhao
- Integrated Program in Neuroscience, McGill University, Montréal, QC, Canada
| | - Arjun A Bhaskaran
- Integrated Program in Neuroscience, McGill University, Montréal, QC, Canada; Pharmacology and Therapeutics, McGill University, Montréal, QC, Canada
| | - Derek Bowie
- Integrated Program in Neuroscience, McGill University, Montréal, QC, Canada; Pharmacology and Therapeutics, McGill University, Montréal, QC, Canada
| | | | - Ellis Cooper
- Integrated Program in Neuroscience, McGill University, Montréal, QC, Canada; Department of Physiology, McGill University, Montréal, QC, Canada.
| | - A Pejmun Haghighi
- Integrated Program in Neuroscience, McGill University, Montréal, QC, Canada; Department of Physiology, McGill University, Montréal, QC, Canada; Buck Institute for Research on Aging, Novato, CA, USA.
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Cooper E, Crawford E, Maher J, Chinn J, Runge A, Bera K, Zezoff D, Dinicu A, Naaseh A, Lucas A, White K, Tewari S, Hari A, Bernstein M, Chang J, Ziogas A, Pearre D, Tewari K. Feasibility Of Visual Inspection With Acetic Acid (VIA) Screening For Cervical Cancer In Tanzania With Emphasis On Baseline Knowledge And Educational Intervention. Gynecol Oncol 2020. [DOI: 10.1016/j.ygyno.2019.11.047] [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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6
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Ariyaratne H, Scott E, Anderson A, Cooper E, Pasciuti K. Linac-based stereotactic ablative radiotherapy for lung cancer: single-institution outcomes. Lung Cancer 2020. [DOI: 10.1016/s0169-5002(20)30105-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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7
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Chong Y, Saviuk N, Pie B, Basisty N, Quinn RK, Schilling B, Sonenberg N, Cooper E, Haghighi AP. Removing 4E-BP Enables Synapses to Refine without Postsynaptic Activity. Cell Rep 2019; 23:11-22. [PMID: 29617653 DOI: 10.1016/j.celrep.2018.03.040] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [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: 10/20/2016] [Revised: 02/02/2018] [Accepted: 03/10/2018] [Indexed: 11/29/2022] Open
Abstract
Throughout the developing nervous system, considerable synaptic re-organization takes place as postsynaptic neurons extend dendrites and incoming axons refine their synapses, strengthening some and eliminating others. It is well accepted that these processes rely on synaptic activity; however, the mechanisms that lead to this developmental reorganization are not fully understood. Here, we explore the regulation of cap-dependent translation, a mechanism known to play a role in synaptic growth and plasticity. Using sympathetic ganglia in α3 nicotinic acetylcholine receptor (nAChR)-knockout (KO) mice, we establish that electrophysiologically silent synapses between preganglionic axons and postsynaptic sympathetic neurons do not refine, and the growth of dendrites and the targeting of synapses on postsynaptic neurons are impaired. Remarkably, genetically removing 4E-BP, a suppressor of cap-dependent translation, from these α3 nAChR-KO mice largely restores these features. We conclude that synaptic connections can re-organize and refine without postsynaptic activity during post-natal development when 4E-BP-regulated cap-dependent translation is enhanced.
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Affiliation(s)
- Yumaine Chong
- Department of Physiology, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Natasha Saviuk
- Department of Physiology, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Brigitte Pie
- Department of Physiology, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Nathan Basisty
- Buck Institute for Research on Aging, Novato, CA 94945, USA
| | - Ryan K Quinn
- Buck Institute for Research on Aging, Novato, CA 94945, USA
| | | | - Nahum Sonenberg
- Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Ellis Cooper
- Department of Physiology, McGill University, Montreal, QC H3G 1Y6, Canada.
| | - A Pejmun Haghighi
- Department of Physiology, McGill University, Montreal, QC H3G 1Y6, Canada; Buck Institute for Research on Aging, Novato, CA 94945, USA.
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8
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Schindler A, Meabon J, Baskin B, Cooper E, Yagi M, Simon B, Peskind E, Phillips P, Cook D. Non-invasive vagus nerve stimulation for the prevention/treatment of comorbid mild traumatic brain injury and PTSD. Brain Stimul 2019. [DOI: 10.1016/j.brs.2018.12.356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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9
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Ariyaratne H, Chander A, Anderson A, Pasciuti K, Cooper E. Stereotactic ablative radiotherapy for second primary lung malignancy arising post-pneumonectomy. Lung Cancer 2019. [DOI: 10.1016/s0169-5002(19)30220-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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10
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Bagheri H, Friedman H, Shao H, Chong Y, Lo CA, Emran F, Kays I, Yang XJ, Cooper E, Chen BE, Siminovitch K, Peterson A. TIE: A Method to Electroporate Long DNA Templates into Preimplantation Embryos for CRISPR-Cas9 Gene Editing. CRISPR J 2018; 1:223-229. [PMID: 31021258 PMCID: PMC6636866 DOI: 10.1089/crispr.2017.0020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Precise genome editing using CRISPR typically requires delivery of guide RNAs, Cas9 endonuclease, and DNA repair templates. Both microinjection and electroporation effectively deliver these components into mouse zygotes provided the DNA template is an oligonucleotide of only a few hundred base pairs. However, electroporation completely fails with longer double-stranded DNAs leaving microinjection as the only delivery option. Here, we overcome this limitation by first injecting all CRISPR components, including long plasmid-sized DNA templates, into the sub-zona pellucida space. There they are retained, supporting subsequent electroporation. We show that this simple and well-tolerated method achieves intracellular reagent concentrations sufficient to effect precise gene edits.
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Affiliation(s)
- Hooman Bagheri
- 1 Laboratory of Developmental Biology, McGill University , Montreal, Quebec, Canada.,2 Department of Human Genetics, McGill University , Montreal, Quebec, Canada
| | - Hana Friedman
- 1 Laboratory of Developmental Biology, McGill University , Montreal, Quebec, Canada.,2 Department of Human Genetics, McGill University , Montreal, Quebec, Canada.,3 Department of Neurology and Neurosurgery, McGill University , Montreal, Quebec, Canada.,4 Department of Oncology, McGill University , Montreal, Quebec, Canada
| | - Harry Shao
- 1 Laboratory of Developmental Biology, McGill University , Montreal, Quebec, Canada
| | - Yumaine Chong
- 5 Department of Physiology, McGill University , Montreal, Quebec, Canada
| | - Chiu-An Lo
- 6 Centre for Research in Neuroscience, Research Institute of the McGill University Health Centre , Montreal, Quebec, Canada
| | - Farida Emran
- 6 Centre for Research in Neuroscience, Research Institute of the McGill University Health Centre , Montreal, Quebec, Canada
| | - Ibrahim Kays
- 6 Centre for Research in Neuroscience, Research Institute of the McGill University Health Centre , Montreal, Quebec, Canada
| | - Xiang-Jiao Yang
- 7 Department of Biochemistry, McGill University , Montreal, Quebec, Canada
| | - Ellis Cooper
- 5 Department of Physiology, McGill University , Montreal, Quebec, Canada
| | - Brian E Chen
- 6 Centre for Research in Neuroscience, Research Institute of the McGill University Health Centre , Montreal, Quebec, Canada
| | - Katherine Siminovitch
- 8 Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital , Toronto, Ontario, Canada
| | - Alan Peterson
- 1 Laboratory of Developmental Biology, McGill University , Montreal, Quebec, Canada.,2 Department of Human Genetics, McGill University , Montreal, Quebec, Canada.,3 Department of Neurology and Neurosurgery, McGill University , Montreal, Quebec, Canada.,4 Department of Oncology, McGill University , Montreal, Quebec, Canada
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11
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Taylor A, Cooper E, Ham K. Delayed intestinal perforation secondary to blunt force abdominal trauma in a cat. JFMS Open Rep 2018; 4:2055116918763410. [PMID: 29662682 PMCID: PMC5894924 DOI: 10.1177/2055116918763410] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Case summary A 7-month-old intact male domestic shorthair cat was presented 4 h after being hit by a car. It had bilateral inguinal hernias and a mesenteric rent that were repaired surgically and a hematoma in the left retroperitoneal space. No other intra-abdominal abnormalities were identified on abdominal surgical exploration. Approximately 72 h after presentation, the cat started vomiting and developed severe abdominal discomfort. A sudden decrease in mentation and elevation of respiratory rate and effort ensued. Abdominal radiographs showed loss of detail in the abdominal cavity, and abdominocentesis confirmed septic peritonitis. The cat was euthanized, and post-mortem evaluation of the bowel revealed two 1 cm perforations of the jejunum. Relevance and novel information To our knowledge, delayed intestinal perforation secondary to blunt force abdominal trauma has not previously been reported in cats. It has been reported in dogs, but the pathophysiology resulting in perforation is poorly understood. Delayed intestinal injury secondary to blunt force abdominal trauma has been reported in people, especially in children, as a result of motor vehicle accidents.
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Affiliation(s)
- A Taylor
- Cummings School of Veterinary Medicine at Tufts University, North Grafton, MA, USA
| | - E Cooper
- Department of Emergency and Critical Care, The Ohio State University, Columbus, OH, USA
| | - K Ham
- Department of Veterinary Clinical Sciences - Small Animal Surgery, The Ohio State University, Columbus, OH, USA
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12
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Gandhi S, Ewing J, Cooper E, Chaves J, Gray B. Comparison of Low-Dose Catheter-Directed Thrombolysis With and Without Pharmacomechanical Thrombectomy for Acute Lower Extremity Ischemia. J Vasc Surg 2018. [DOI: 10.1016/j.jvs.2018.02.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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13
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Moujaber O, Omran N, Kodiha M, Pié B, Cooper E, Presley JF, Stochaj U. Data on the association of the nuclear envelope protein Sun1 with nucleoli. Data Brief 2017; 13:115-123. [PMID: 28580408 PMCID: PMC5447391 DOI: 10.1016/j.dib.2017.05.028] [Citation(s) in RCA: 3] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2016] [Revised: 05/10/2017] [Accepted: 05/11/2017] [Indexed: 11/01/2022] Open
Abstract
SUN proteins participate in diverse cellular activities, many of which are connected to the nuclear envelope. Recently, the family member SUN1 has been linked to novel biological activities. These include the regulation of nucleoli, intranuclear compartments that assemble ribosomal subunits. We show that SUN1 associates with nucleoli in several mammalian epithelial cell lines. This nucleolar localization is not shared by all cell types, as SUN1 concentrates at the nuclear envelope in ganglionic neurons and non-neuronal satellite cells. Database analyses and Western blotting emphasize the complexity of SUN1 protein profiles in different mammalian cells. We constructed a STRING network which identifies SUN1-related proteins as part of a larger network that includes several nucleolar proteins. Taken together, the current data highlight the diversity of SUN1 proteins and emphasize the possible links between SUN1 and nucleoli.
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Affiliation(s)
| | - Nawal Omran
- Physiology, McGill University, Montreal, Canada
| | | | | | | | - John F Presley
- Anatomy & Cell Biology, McGill University, Montreal, Canada
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Cooper E, Sheikh Z, Townend W, Johnson M, Hutchinson A. PALLIATIVE CARE IN THE EMERGENCY DEPARTMENT: A SYSTEMATIC REVIEW. Arch Emerg Med 2016. [DOI: 10.1136/emermed-2016-206402.38] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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15
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Jefferson L, Fairhurst C, Cooper E, Hewitt C, Torgerson T, Cook L, Tharmanathan P, Cockayne S, Torgerson D. No difference found in time to publication by statistical significance of trial results: a methodological review. JRSM Open 2016; 7:2054270416649283. [PMID: 27757242 PMCID: PMC5052771 DOI: 10.1177/2054270416649283] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Objective Time-lag from study completion to publication is a potential source of publication bias in randomised controlled trials. This study sought to update the evidence base by identifying the effect of the statistical significance of research findings on time to publication of trial results. Design Literature searches were carried out in four general medical journals from June 2013 to June 2014 inclusive (BMJ, JAMA, the Lancet and the New England Journal of Medicine). Setting Methodological review of four general medical journals. Participants Original research articles presenting the primary analyses from phase 2, 3 and 4 parallel-group randomised controlled trials were included. Main outcome measures Time from trial completion to publication. Results The median time from trial completion to publication was 431 days (n = 208, interquartile range 278–618). A multivariable adjusted Cox model found no statistically significant difference in time to publication for trials reporting positive or negative results (hazard ratio: 0.86, 95% CI 0.64 to 1.16, p = 0.32). Conclusion In contrast to previous studies, this review did not demonstrate the presence of time-lag bias in time to publication. This may be a result of these articles being published in four high-impact general medical journals that may be more inclined to publish rapidly, whatever the findings. Further research is needed to explore the presence of time-lag bias in lower quality studies and lower impact journals.
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Affiliation(s)
- L Jefferson
- York Trials Unit, Department of Health Sciences, University of York, York YO10 5DD, UK
| | - C Fairhurst
- York Trials Unit, Department of Health Sciences, University of York, York YO10 5DD, UK
| | - E Cooper
- Elderly medicine, York Hospital, York YO31 8HE, UK
| | - C Hewitt
- York Trials Unit, Department of Health Sciences, University of York, York YO10 5DD, UK
| | - T Torgerson
- York Trials Unit, Department of Health Sciences, University of York, York YO10 5DD, UK
| | - L Cook
- York Trials Unit, Department of Health Sciences, University of York, York YO10 5DD, UK
| | - P Tharmanathan
- York Trials Unit, Department of Health Sciences, University of York, York YO10 5DD, UK
| | - S Cockayne
- York Trials Unit, Department of Health Sciences, University of York, York YO10 5DD, UK
| | - D Torgerson
- York Trials Unit, Department of Health Sciences, University of York, York YO10 5DD, UK
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16
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Czaplicki LM, Cooper E, Ferguson PL, Stapleton HM, Vilgalys R, Gunsch CK. A New Perspective on Sustainable Soil Remediation-Case Study Suggests Novel Fungal Genera Could Facilitate in situ Biodegradation of Hazardous Contaminants. ACTA ACUST UNITED AC 2016; 26:59-72. [PMID: 27917031 DOI: 10.1002/rem.21458] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Deciding upon a cost effective and sustainable method to address soil pollution is a challenge for many remedial project managers. High pressure to quickly achieve cleanup goals pushes for energy-intensive remedies that rapidly address the contaminants of concern with established technologies, often leaving little room for research and development especially for slower treatment technologies, such as bioremediation, for the more heavily polluted sites. In the present case study, new genomic approaches have been leveraged to assess fungal biostimulation potential in soils polluted with particularly persistent hydrophobic contaminants. This new approach provides insights into the genetic functions available at a given site in a way never before possible. In particular, this article presents a case study where next generation sequencing (NGS) has been used to categorize fungi in soils from the Atlantic Wood Industries Superfund site in Portsmouth, Virginia. Data suggest that original attempts to harness fungi for bioremediation may have focused on fungal genera poorly suited to survive under heavily polluted site conditions, and that more targeted approaches relying on native indigenous fungi which are better equipped to survive under site specific conditions may be more appropriate.
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Affiliation(s)
- L M Czaplicki
- Candidate and Dean's Graduate Fellow in the Department of Civil and Environmental Engineering at Duke University in Durham, North Carolina. Her doctoral thesis focuses on fungal bioremediation of high molecular weight polycyclic aromatic hydrocarbon contaminated soils. She received her M.S. from Duke University and her B.S. in Environmental Engineering from The Ohio State University
| | - E Cooper
- research scientist and she manages the Duke Superfund Analytical Chemistry Core in Durham, North Carolina. Dr. Cooper is interested in analyzing environmentally important organic compounds in a variety of matrices including sediments, water, biological samples, and polyurethane foam. She received her Ph.D. in Environmental Sciences from Duke University. She earned her B.S in Plant Science and her M.S. in Plant and Soil Sciences from the University of Delaware
| | - P L Ferguson
- an associate professor of Environmental Chemistry and Engineering in the Department of Civil and Environmental Engineering and the Nicholas School of the Environment at Duke University in Durham, North Carolina. His research focuses on developing new methods for trace analysis of organic and nanoparticulate contaminants in the aquatic environment. Dr. Ferguson received his Ph.D. from the State University of New York at Stony Brook in Coastal Oceanography. He received his B.S. in Marine Science and Chemistry from the University of South Carolina
| | - H M Stapleton
- an associate professor in the Nicholas School of the Environment. Her research increases the understanding of the fate and transformation of organic contaminants in aquatic systems and indoor environments. Dr. Stapleton received her Ph.D. and M.S. from the University of Maryland, and her B.S. from Long Island University Southampton College
| | - R Vilgalys
- professor in the Department of Biology and adjunct professor in the Department of Molecular Genetics and Microbiology at Duke University in Durham, North Carolina. His research focuses on fungal evolution, genetics and systematics. Dr. Vilgalys received his Ph.D. in Botany from Virginia Polytechnic Institute and State University. He received his M.S. in Botany from Virginia Tech and his B.A. in Biology from the State University of New York College at Genesco
| | - C K Gunsch
- an associate professor in the Department of Civil and Environmental Engineering at Duke University in Durham, North Carolina. Her research focuses on characterizing and engineering environmental microbiomes. Dr. Gunsch received her Ph.D. in Civil Engineering from the University of Texas at Austin. She received her M.S. in Environmental Engineering and Science from Clemson University and her B.S. in Civil Engineering from Purdue University
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17
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Mundinger TO, Cooper E, Coleman MP, Taborsky GJ. Short-term diabetic hyperglycemia suppresses celiac ganglia neurotransmission, thereby impairing sympathetically mediated glucagon responses. Am J Physiol Endocrinol Metab 2015; 309:E246-55. [PMID: 26037249 PMCID: PMC4525110 DOI: 10.1152/ajpendo.00140.2015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 05/25/2015] [Indexed: 01/09/2023]
Abstract
Short-term hyperglycemia suppresses superior cervical ganglia neurotransmission. If this ganglionic dysfunction also occurs in the islet sympathetic pathway, sympathetically mediated glucagon responses could be impaired. Our objectives were 1) to test for a suppressive effect of 7 days of streptozotocin (STZ) diabetes on celiac ganglia (CG) activation and on neurotransmitter and glucagon responses to preganglionic nerve stimulation, 2) to isolate the defect in the islet sympathetic pathway to the CG itself, and 3) to test for a protective effect of the WLD(S) mutation. We injected saline or nicotine in nondiabetic and STZ-diabetic rats and measured fos mRNA levels in whole CG. We electrically stimulated the preganglionic or postganglionic nerve trunk of the CG in nondiabetic and STZ-diabetic rats and measured portal venous norepinephrine and glucagon responses. We repeated the nicotine and preganglionic nerve stimulation studies in nondiabetic and STZ-diabetic WLD(S) rats. In STZ-diabetic rats, the CG fos response to nicotine was suppressed, and the norepinephrine and glucagon responses to preganglionic nerve stimulation were impaired. In contrast, the norepinephrine and glucagon responses to postganglionic nerve stimulation were normal. The CG fos response to nicotine, and the norepinephrine and glucagon responses to preganglionic nerve stimulation, were normal in STZ-diabetic WLD(S) rats. In conclusion, short-term hyperglycemia's suppressive effect on nicotinic acetylcholine receptors of the CG impairs sympathetically mediated glucagon responses. WLD(S) rats are protected from this dysfunction. The implication is that this CG dysfunction may contribute to the impaired glucagon response to insulin-induced hypoglycemia seen early in type 1 diabetes.
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MESH Headings
- Animals
- Diabetes Mellitus, Type 1/blood
- Diabetes Mellitus, Type 1/complications
- Diabetes Mellitus, Type 1/metabolism
- Diabetes Mellitus, Type 1/physiopathology
- Down-Regulation/drug effects
- Electric Stimulation
- Ganglia, Sympathetic/drug effects
- Ganglia, Sympathetic/metabolism
- Ganglia, Sympathetic/physiopathology
- Ganglionic Stimulants/pharmacology
- Glucagon/blood
- Glucagon/metabolism
- Hyperglycemia/etiology
- Islets of Langerhans/drug effects
- Islets of Langerhans/innervation
- Islets of Langerhans/metabolism
- Male
- Mutant Proteins/metabolism
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Neurons/drug effects
- Neurons/metabolism
- Nicotinic Agonists/pharmacology
- Norepinephrine/blood
- Norepinephrine/metabolism
- Proto-Oncogene Proteins c-fos/genetics
- Proto-Oncogene Proteins c-fos/metabolism
- Rats, Sprague-Dawley
- Rats, Transgenic
- Rats, Wistar
- Receptors, Nicotinic/chemistry
- Receptors, Nicotinic/metabolism
- Synaptic Transmission/drug effects
- Wallerian Degeneration/complications
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Affiliation(s)
| | - Ellis Cooper
- Department of Physiology, McGill University, Montreal, Quebec, Canada
| | - Michael P Coleman
- The Babraham Institute, Babraham Research Campus, Babraham, Cambridge, United Kingdom; and
| | - Gerald J Taborsky
- Department of Medicine, University of Washington, Seattle, Washington; Veterans Affairs Puget Sound Health Care System, Seattle, Washington
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Norcia A, Ales J, Cooper E, Wiegand T. Measuring perceptual differences between compressed and uncompressed video sequences using the swept-parameter Visual Evoked Potential. J Vis 2014. [DOI: 10.1167/14.10.649] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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19
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Sprague W, Cooper E, Durand JB, Banks M. Disparity Preferences in V1 Reflect the Statistics of Disparity in Natural Viewing. J Vis 2014. [DOI: 10.1167/14.10.1111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Kipling SL, Young K, Foster JD, Smart NJ, Hunter AE, Cooper E, Francis NK. Laparoscopic extralevator abdominoperineal excision of the rectum: short-term outcomes of a prospective case series. Tech Coloproctol 2013; 18:445-51. [PMID: 24081545 DOI: 10.1007/s10151-013-1071-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [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] [Received: 06/13/2013] [Accepted: 09/06/2013] [Indexed: 12/27/2022]
Abstract
BACKGROUND Laparoscopic approaches for the resection of low rectal cancer and the extralevator technique for abdominoperineal excision are both becoming increasingly popular. There are little published data regarding the combined application of these techniques to the resection of low rectal tumours. The aim of this study was to assess the feasibility of such an approach and to appraise short-term outcomes in a consecutive series of patients undergoing laparoscopic extralevator abdominoperineal excision (ELAPE). METHODS Consecutive patients undergoing laparoscopic ELAPE at our institution between 2008 and 2011 were identified from a prospectively maintained database. The abdominal phase of the operation was performed laparoscopically, and following extralevator resection, the perineum was reconstructed using a biologic mesh. All patients were enrolled in an enhanced recovery programme. RESULTS Of 166 patients undergoing radical resection of rectal cancer at our institution between 2008 and 2011, 28 underwent laparoscopic ELAPE. Median age was 70 years, median body mass index was 27.5 kg/m(2), and 71% were male. The conversion rate to laparotomy was 18%. Three patients (10.8%) had circumferential resection margins <1 mm; no intraoperative tumour perforation occurred. The median length of stay was 7 days, with a 30-day readmission rate of 21% and no 30-day mortality. Post-operative perineal wound complications occurred in 25%. At median 38-month follow-up (range 23-66 months), overall survival was 75%, disease-free survival was 71%, and there were three local recurrences (11%). CONCLUSIONS Laparoscopic extralevator abdominoperineal excision can be safely performed without compromising short-term outcomes.
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Affiliation(s)
- S L Kipling
- Department of General Surgery, Yeovil District Hospital, Higher Kingston, Yeovil, BA21 4AT, UK
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Abstract
Mortality statistics for excessive alcohol consumption show no signs of abatement, with a report published in 2011 from the World Health Organization (WHO) estimating that 2.5 million people worldwide died because of their alcohol consumption. Serious physiological, psychological, social and legal problems are thought to affect many more. Alcohol withdrawal syndrome (AWS) is a potentially life-threatening condition that often occurs in those individuals who significantly reduce or stop their intake after a prolonged and excessive period of drinking. Pharmacological treatment of the AWS has traditionally been undertaken by the use of the benzodiazepines, but recent years have witnessed the emergence of several alternatives. The aim of this paper was (1) to review the evidence base supporting the use of various pharmacological agents currently employed to treat AWS, and (2) to consider the efficacy and safety of the emerging alternatives to the benzodiazepines. The Cochrane Database of Systematic Reviews, CINAHL, Embase, PsycINFO, MEDLINE and BNI databases were extensively searched in order to retrieve the maximum number of relevant articles. Reference lists from relevant literature were also used to identify other potential studies for inclusion. All studies concerned with measuring the efficacy and safety of the various pharmacological treatment options for AWS were considered and a total of 63 trials were included in this review. Findings support the use of benzodiazepines as the recommended drug of choice for the treatment of AWS in the absence of adequate evidence to support the use of alternative agents. There is a lack of evidence of a superior pharmacological agent to the benzodiazepines for the treatment of AWS. There are several studies that have shown that there are pharmacological alternatives that could compete or act as an adjunct with the benzodiazepines in terms of high efficacy and safety in the treatment of AWS, but there is a need for further quality research to be carried out before definitive conclusions can be drawn.
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Affiliation(s)
- E Cooper
- Community Mental Health Team, Pennine Care NHS foundation Trust, Stockport , UK
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Lukashova V, Jinadasa T, Ilie A, Verbich D, Cooper E, Orlowski J. The Na(+)/H (+) exchanger NHE5 is sorted to discrete intracellular vesicles in the central and peripheral nervous systems. Adv Exp Med Biol 2013; 961:397-410. [PMID: 23224898 DOI: 10.1007/978-1-4614-4756-6_34] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The pH milieu of the central and peripheral nervous systems is an important determinant of neuronal excitability, function, and survival. In mammals, neural acid-base homeostasis is coordinately regulated by ion transporters belonging to the Na(+)/H(+) exchanger (NHE) and bicarbonate transporter gene families. However, the relative contributions of individual isoforms within the respective families are not fully understood. This report focuses on the NHE family, specifically the plasma membrane-type NHE5 which is preferentially transcribed in brain, but the distribution of the native protein has not been extensively characterized. To this end, we generated a rabbit polyclonal antibody that specifically recognizes NHE5. In both central (cortex, hippocampus) and peripheral (superior cervical ganglia, SCG) nervous tissue of mice, NHE5 immunostaining was punctate and highly concentrated in the somas and to lesser amounts in the dendrites of neurons. Very little signal was detected in axons. Similarly, in primary cultures of differentiated SCG neurons, NHE5 localized predominantly to vesicles in the somatodendritic compartment, though some immunostaining was also evident in punctate vesicles along the axons. NHE5 was also detected predominantly in intracellular vesicles of cultured SCG glial cells. Dual immunolabeling of SCG neurons showed that NHE5 did not colocalize with markers for early endosomes (EEA1) or synaptic vesicles (synaptophysin), but did partially colocalize with the transferrin receptor, a marker of recycling endosomes. Collectively, these data suggest that NHE5 partitions into a unique vesicular pool in neurons that shares some characteristics of recycling endosomes where it may serve as an important regulated store of functional transporters required to maintain cytoplasmic pH homeostasis.
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Charlebois A, Lee L, Cooper E, Mason K, Powis J. Factors associated with HCV antiviral treatment uptake among participants of a community-based HCV programme for marginalized patients. J Viral Hepat 2012; 19:836-42. [PMID: 23121361 DOI: 10.1111/j.1365-2893.2012.01648.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Accepted: 06/03/2012] [Indexed: 01/29/2023]
Abstract
While the majority of cases of hepatitis C virus (HCV) in developed countries occur among illicit drug users, HCV antiviral treatment uptake is poor in this population. Several studies have shown that patients can successfully be treated for HCV in the context of methadone maintenance programmes, but little evidence exists evaluating HCV treatment models for substance users where methadone maintenance is not indicated. This retrospective cohort study involved 129 persons participating in psycho-educational support groups and integrated, interprofessional, community-based health services focused on the treatment for HCV among marginalized populations with high rates of crack cocaine use and mental health comorbidities. We sought to identify the factors associated with antiviral treatment uptake. Group participation improved access to health care. While 19% had previously seen an HCV specialist prior to group initiation, 59% saw an HCV specialist during the group. Half of the participants were nonimmune to hepatitis A or B at baseline, and 80% of these patients received immunization through the programme. The programme treated 24 patients with pegylated interferon and ribavirin and achieved a sustained virologic response (SVR) rate of 91% for genotype 2 or 3 and 54% for genotype 1. Stable housing was independently associated with initiation of treatment, and there was a nonsignificant trend towards lower rates of treatment initiation among women. SVR rates for those who had used crack or injection drugs in the month prior to joining the programme did not differ significantly from those who had abstained.
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Affiliation(s)
- A Charlebois
- Department of Family and Community Medicine, University of Toronto, Toronto, ON, Canada
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Krishnaswamy A, Cooper E. Reactive oxygen species inactivate neuronal nicotinic acetylcholine receptors through a highly conserved cysteine near the intracellular mouth of the channel: implications for diseases that involve oxidative stress. J Physiol 2012; 590:39-47. [PMID: 21969449 PMCID: PMC3300044 DOI: 10.1113/jphysiol.2011.214007] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [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: 06/13/2011] [Accepted: 10/02/2011] [Indexed: 11/08/2022] Open
Abstract
An intriguing feature of several nicotinic acetylcholine receptors (nAChRs) on neurons is that their subunits contain a highly conserved cysteine residue located near the intracellular mouth of the receptor pore. The work summarized in this review indicates that α3β4-containing and α4β2-containing neuronal nAChRs, and possibly other subtypes, are inactivated by elevations in intracellular reactive oxygen species (ROS). This review discusses a model for the molecular mechanisms that underlie this inactivation. In addition, we explore the implications of this mechanism in the context of complications that arise from diabetes. We review the evidence that diabetes elevates cytosolic ROS in sympathetic neurons and inactivates postsynaptic α3β4-containing nAChRs shortly after the onset of diabetes, leading to a depression of synaptic transmission in sympathetic ganglia, an impairment of sympathetic reflexes. These effects of ROS on nAChR function are due to the highly conserved Cys residues in the receptors: replacing the cysteine residues in α3 allow ganglionic transmission and sympathetic reflexes to function normally in diabetes. This example from diabetes suggests that other diseases involving oxidative stress, such as Parkinson's disease, could lead to the inactivation of nAChRs on neurons and disrupt cholinergic nicotinic signalling.
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Gurav K, Cooper E, Junno J, Stein D, Chintada DR, Doddamane M, Moses S. P2-S2.21 Traditional devadasi system under transition: boon or bane for HIV prevention programme? Sex Transm Infect 2011. [DOI: 10.1136/sextrans-2011-050108.317] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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26
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Cooper E, Watson L. A retrospective audit of weight loss in bariatric surgery patients. J Hum Nutr Diet 2011. [DOI: 10.1111/j.1365-277x.2011.01177_12.x] [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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Held R, Cooper E, O'Brien J, Banks M. Making big things look small: Blur combined with other depth cues affects perceived size and distance. J Vis 2010. [DOI: 10.1167/9.8.959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Campanucci V, Krishnaswamy A, Cooper E. Diabetes depresses synaptic transmission in sympathetic ganglia by inactivating nAChRs through a conserved intracellular cysteine residue. Neuron 2010; 66:827-34. [PMID: 20620869 DOI: 10.1016/j.neuron.2010.06.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/08/2010] [Indexed: 10/19/2022]
Abstract
Most people with diabetes develop severe complications of the autonomic nervous system; yet, the underlying causes of many diabetic-induced dysautonomias are poorly understood. Here we explore the idea that these dysautonomias results, in part, from a defect in synaptic transmission. To test this idea, we investigated cultured sympathetic neurons and show that hyperglycemia inactivates nAChRs through a mechanism involving an elevation in reactive oxygen species and an interaction with highly conserved cysteine residues located near the intracellular mouth of the nAChR channel. Consistent with this, we show that diabetic mice have depressed ganglionic transmission and reduced sympathetic reflexes, whereas diabetic mice expressing mutant postsynaptic nAChRs that lack the conserved cysteine residues on the alpha3 subunit have normal synaptic transmission in sympathetic ganglia and normal sympathetic reflexes. Our work suggests a new model for diabetic-induced dysautonomias and identifies ganglionic nAChRs as targets of hyperglycemia-induced downstream signals.
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Affiliation(s)
- Verónica Campanucci
- Department of Physiology, McGill University, Montreal, Quebec H3G 1Y6, Canada
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Cooper E, Iqbal A, Bartlett A, Marriott C, Whitfield PJ, Brown MB. A comparison of topical formulations for the prevention of human schistosomiasis. J Pharm Pharmacol 2010; 56:957-62. [PMID: 15285838 DOI: 10.1211/0022357043996] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Abstract
Recently, a dimeticone formulation has been shown to be effective at preventing Schistosoma cercariae infecting skin, while DEET (N,N-diethyl-m-toluamide), a highly effective insecticide, has been shown to have activity against cercariae. Seven formulations, 3 containing DEET, were prepared and applied to excised human skin in Franz cells for 1 h. Schistosoma cercariae were applied for 30 min at 1 and 24 h, and the number that penetrated the skin calculated (n = 9). DEET could not be incorporated into the dimeticone formulation, yet it remained the most effective at preventing cercarial penetration, both 1 and 24 h after application. The ointments that contained DEET did prevent penetration but their mode of action was due to the toxicity of DEET against the cercariae. The persistence of the protection afforded by the dimeticone formulation after washing suggests that the formulation may be interacting with the stratum corneum to prevent cercarial recognition of skin.
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Affiliation(s)
- E Cooper
- Department of Pharmacy, King's College London, 150 Stamford St, SE1 9NN, UK
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Caffery PM, Krishnaswamy A, Sanders T, Liu J, Hartlaub H, Klysik J, Cooper E, Hawrot E. Engineering neuronal nicotinic acetylcholine receptors with functional sensitivity to alpha-bungarotoxin: a novel alpha3-knock-in mouse. Eur J Neurosci 2009; 30:2064-76. [PMID: 20128845 DOI: 10.1111/j.1460-9568.2009.07016.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We report here the construction of a novel knock-in mouse expressing chimeric alpha3 nicotinic acetylcholine receptor (nAChR) subunits with pharmacological sensitivity to alpha-bungarotoxin (alphaBTX). Sensitivity was generated by substituting five amino acids in the loop C (beta9-beta10) region of the mouse alpha3 subunit with the corresponding residues from the alpha1 subunit of the muscle type receptor from Torpedo californica. To demonstrate the utility of the underlying concept, expressed alpha3[5] subunits were characterized in the superior cervical ganglia (SCG) of homozygous knock-in mice, where the synaptic architecture of postsynaptic alpha3-containing nAChR clusters could now, for the first time, be directly visualized and interrogated by live-staining with rhodamine-conjugated alphaBTX. Consistent with the postsynaptic localization of ganglionic nAChRs, the alphaBTX-labeled puncta colocalized with a marker for synaptic varicosities. Following in vivo deafferentation, these puncta persisted but with significant changes in intensity and distribution that varied with the length of the recovery period. Compound action potentials and excitatory postsynaptic potentials recorded from SCG of mice homozygous for alpha3[5] were abolished by 100 nmalphaBTX, even in an alpha7 null background, demonstrating that synaptic throughput in the SCG is completely dependent on the alpha3-subunit. In addition, we observed that the genetic background of various inbred and outbred mouse lines greatly affects the functional expression of alpha3[5]-nAChRs, suggesting a powerful new approach for exploring the molecular mechanisms underlying receptor assembly and trafficking. As alphaBTX-sensitive sequences can be readily introduced into other nicotinic receptor subunits normally insensitive to alphaBTX, the findings described here should be applicable to many other receptors.
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Affiliation(s)
- Philip M Caffery
- Department of Molecular Pharmacology, Brown University, Providence, RI, USA
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Krishnaswamy A, Cooper E. An activity-dependent retrograde signal induces the expression of the high-affinity choline transporter in cholinergic neurons. Neuron 2009; 61:272-86. [PMID: 19186169 DOI: 10.1016/j.neuron.2008.11.025] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2008] [Revised: 10/15/2008] [Accepted: 11/24/2008] [Indexed: 10/21/2022]
Abstract
A well-accepted view of developing circuits is that synapses must be active to mature and persist, whereas inactive synapses remain immature and are eventually eliminated. We question this long-standing view by investigating nonfunctional cholinergic nicotinic synapses in the superior cervical ganglia (SCG) of mice with a disruption in the alpha3 nicotinic receptor (nAChR) subunit gene, a gene essential for fast synaptic transmission in sympathetic ganglia. Using imaging and electrophysiology, we show that synapses persist for at least 2-3 months without postsynaptic activity; however, the presynaptic terminals lack high-affinity choline transporters (CHTs), and as a result, they are quickly depleted of transmitter. Moreover, we demonstrate with rescue experiments that CHT is induced by signals downstream of postsynaptic activity, converting immature terminals to mature terminals capable of sustaining transmitter release in response to high-frequency or continuous firing. Importantly, postsynaptic neurons must be continually active to maintain CHT in presynaptic terminals.
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Affiliation(s)
- Arjun Krishnaswamy
- Department of Physiology, McGill University, Montreal, H3G 1Y6 Quebec, Canada
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Affiliation(s)
- H Kahal
- Department of Diabetes and Endocrinology, Poole Hospital NHS Foundation Trust, Poole BH15 2JB.
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Abstract
Neuronal synapse formation is a multistep process regulated by several pre- and postsynaptic adhesion and signaling proteins. Recently, we found that agrin acts as one such synaptogenic factor at neuronal synapses in the PNS by demonstrating that structural synapse formation is impaired in the superior cervical ganglia (SCG) of z+ agrin-deficient mice and in SCG cultures derived from those animals. Here, we tested whether synaptic function is defective in agrin-null (AGD-/-) ganglia and began to define agrin's mechanism of action. Our electrophysiological recordings of compound action potentials showed that presynaptic stimulation evoked action potentials in approximately 40% of AGD-/- ganglionic neurons compared to 90% of wild-type neurons; moreover, transmission could not be potentiated as in wild-type or z+ agrin-deficient ganglia. Intracellular recordings also showed that nerve-evoked excitatory postsynaptic potentials in AGD-/- neurons were only 1/3 the size of those in wild-type neurons and mostly subthreshold. Consistent with these defects in transmission, we found an approximately 40-50% decrease in synapse number in AGD-/- ganglia and cultures, and decreased levels of differentiation at the residual synapses in culture. Furthermore, surface levels of acetylcholine receptors (AChRs) were equivalent in cultured AGD-/- and wild-type neurons, and depolarization reduced the synaptic localization of AChRs in AGD-/- but not wild-type neurons. These findings provide the first direct demonstration that agrin is required for proper structural and functional development of an interneuronal synapse in vivo. Moreover, they suggest a novel role for agrin, in stabilizing the postsynaptic density of nAChR at nascent neuronal synapses.
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Affiliation(s)
- Jacinthe Gingras
- Center for Research in Neuroscience, McGill University Health Center, Montreal, QC, H3G 1A4, Canada
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Stanwood N, Cooper E, Nasso J, Guzick D. A pilot randomized controlled trial of LNG-IUD versus DMPA for young postpartum women. Contraception 2006. [DOI: 10.1016/j.contraception.2006.05.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Rassadi S, Krishnaswamy A, Pié B, McConnell R, Jacob MH, Cooper E. A null mutation for the alpha3 nicotinic acetylcholine (ACh) receptor gene abolishes fast synaptic activity in sympathetic ganglia and reveals that ACh output from developing preganglionic terminals is regulated in an activity-dependent retrograde manner. J Neurosci 2006; 25:8555-66. [PMID: 16162937 PMCID: PMC6725660 DOI: 10.1523/jneurosci.1983-05.2005] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [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: 11/21/2022] Open
Abstract
In vertebrates, synaptic activity exerts an important influence on the formation of neural circuits, yet our understanding of its role in directing presynaptic and postsynaptic differentiation during synaptogenesis is incomplete. This study investigates how activity influences synaptic differentiation as synapses mature during early postnatal life. Specifically, we ask what happens to presynaptic terminals when synapses develop without functional postsynaptic receptors and without fast synaptic transmission. To address this issue, we investigated cholinergic nicotinic synapses in sympathetic ganglia of mice with a null mutation for the alpha3 nicotinic ACh receptor gene. Disrupting the alpha3 gene completely eliminates fast excitatory synaptic potentials on postganglionic sympathetic neurons, establishing a crucial role for alpha3-containing postsynaptic receptors in synaptic transmission. Interestingly, the preganglionic nerve terminals form morphologically normal synapses with sympathetic neurons, and these synapses persist without activity in postnatal animals. Surprisingly, when stimulating the preganglionic nerve at physiological rates, we discovered a significant decrease in ACh output from the presynaptic terminals in these alpha3(-/-) sympathetic ganglia. We show that this decrease in ACh output from the presynaptic terminals results, in part, from a lack of functional high-affinity choline transporters. We conclude the following: (1) fast synaptic transmission in mammalian SCG requires alpha3 expression; (2) in the absence of activity, the preganglionic nerve forms synapses that appear morphologically normal and persist for several weeks; and (3) to sustain transmitter release, developing presynaptic terminals require an activity-dependent retrograde signal.
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Affiliation(s)
- Siamak Rassadi
- Department of Physiology, McGill University, Montreal, Quebec, H3G 1Y6, Canada
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Haiduven D, Cooper E, Luther S. Comparison of live versus online bioreadiness training programs for nurses. Am J Infect Control 2005. [DOI: 10.1016/j.ajic.2005.04.055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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De Rossi A, Walker AS, Forni DD, Klein N, Gibb DM, Aboulker JP, Babiker A, Compagnucci A, Darbyshire J, Debré M, Gersten M, Giaquinto C, Gibb DM, Jones A, Aboulker JP, Babiker A, Blanche S, Bohlin AB, Butler K, Castelli-Gattinara G, Clayden P, Darbyshire J, Debré M, de Groot R, Faye A, Giaquinto C, Gibb DM, Griscelli C, Grosch-Wörner I, Levy J, Lyall H, Mellado Pena M, Nadal D, Peckham C, Ramos Amador JT, Rosado L, Rudin C, Scherpbier H, Sharland M, Tovo PA, Valerius N, Wintergerst U, Boucher C, Clerici M, de Rossi A, Klein N, Loveday C, Muñoz-Fernandez M, Pillay D, Rouzioux C, Babiker A, Darbyshire J, Gibb DM, Harper L, Johnson D, Kelleher P, McGee L, Poland A, Walker AS, Aboulker JP, Carrière I, Compagnucci A, Debré M, Eliette V, Leonardo S, Moulinier C, Saidi Y, Galli L, Foot A, Kershaw H, Caul O, Tarnow-Mordi W, Petrie J, McIntyre P, Appleyard K, Gibb DM, Novelli V, Klein N, McGee L, Ewen S, Johnson M, Gibb DM, Cooper E, Fisher T, Barrie R, Norman J, King D, Larsson-Sciard EL. Relationship between Changes in Thymic Emigrants and Cell-Associated HIV-1 Dna in HIV-1-Infected Children Initiating Antiretroviral Therapy. Antivir Ther 2005. [DOI: 10.1177/135965350501000104] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objectives and methods To investigate the relationship between cell-associated HIV-1 dynamics and recent thymic T-cell emigrants, HIV-1 DNA and T-cell receptor rearrangement excision circles (TREC, a marker of recent thymic emigrants) were measured in peripheral blood mononuclear cells in 181 samples from 33 HIV-1-infected children followed for 96 weeks after antiretroviral therapy (ART) initiation. Results At baseline, HIV-1 DNA was higher in children with higher TREC ( P=0.02) and was not related to age, CD4 or HIV-1 RNA in multivariate analyses ( P>0.3). Overall, TREC increased and HIV-1 DNA decreased significantly after ART initiation, with faster HIV-1 DNA declines in children with higher baseline TREC ( P=0.009). The greatest decreases in HIV-1 DNA occurred in children with the smallest increases in TREC levels during ART ( P=0.002). However, this inverse relationship between changes in HIV-1 DNA and TREC tended to vary according to the phase of HIV-1 RNA decline ( P=0.13); for the same increase in TREC, HIV-1 DNA decline was much smaller during persistent or transient viraemia compared with stable HIV-1 RNA suppression. Conclusions Overall, these findings indicate that TREC levels predict HIV-1 DNA response to ART and suggest that immune repopulation by thymic emigrants adversely affects HIV-1 DNA decline in the absence of persistent viral suppression, possibly by providing a cellular source for viral infection and replication.
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Affiliation(s)
| | - Anita De Rossi
- Department of Oncology and Surgical Sciences, AIDS Reference Centre, Padova, Italy
| | | | - Davide De Forni
- Department of Oncology and Surgical Sciences, AIDS Reference Centre, Padova, Italy
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - A Foot
- PHL Regional Virus Laboratory, Bristol
| | - H Kershaw
- PHL Regional Virus Laboratory, Bristol
| | - O Caul
- Ninewells Hospital and Medical School, Dundee
| | | | | | | | | | - DM Gibb
- Newham General Hospital, London
| | | | - N Klein
- Newham General Hospital, London
| | - L McGee
- Newham General Hospital, London
| | - S Ewen
- Newham General Hospital, London
| | | | - DM Gibb
- St Bartholemew's Hospital, London
| | - E Cooper
- St Bartholemew's Hospital, London
| | - T Fisher
- St Bartholemew's Hospital, London
| | | | - J Norman
- Chelsea and Westminster Hospital, London
| | - D King
- University College London Medical School
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Wheeler DG, Cooper E. Weak synaptic activity induces ongoing signaling to the nucleus that is enhanced by BDNF and suppressed by low-levels of nicotine. Mol Cell Neurosci 2004; 26:50-62. [PMID: 15121178 DOI: 10.1016/j.mcn.2003.12.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2003] [Revised: 12/16/2003] [Accepted: 12/22/2003] [Indexed: 11/23/2022] Open
Abstract
The developing nervous system adapts to a wide array of stimuli, in part, by evoking activity-dependent mechanisms that signal to the nucleus and induce long-term modifications in neuronal function. It is well established that one such stimulus is strong synaptic activity. Our interest, however, is whether weak activity generated at developing synapses also signals to the nucleus and if so, can these signals be modulated by extrinsic factors. Using cultured hippocampal neurons and a highly sensitive readout of CRE-mediated gene expression, we demonstrate that weak synaptic transmission, including non-evoked, spontaneous transmitter release, induces ongoing gene expression. These weak synaptic stimuli, acting through NMDA receptors, signal to the nucleus through a MAPK pathway, without a significant contribution of L-type Ca2+ channels. In addition, we show that BDNF, a molecule that has clear effects on synaptic plasticity, enhances this CRE-dependent gene expression by acting upstream of NMDA receptors. On the other hand, low levels of nicotine, which also effects synaptic plasticity, suppress ongoing CRE-mediated gene expression indirectly by acting on GABAergic neurons; this indirect action on gene expression suggests an alternative mechanism for how nicotine produces long-lasting changes.
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Affiliation(s)
- Damian G Wheeler
- Department of Physiology, McGill University, Montréal, Québec, Canada H3G 1Y6
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Liu JT, Wang CH, Chou IC, Sun SS, Koa CH, Cooper E. Regaining consciousness for prolonged comatose patients with right median nerve stimulation. Acta Neurochir Suppl 2003; 87:11-4. [PMID: 14518515 DOI: 10.1007/978-3-7091-6081-7_3] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
During the past half year, we have utilized right median nerve stimulation (produced by Empi. Co. USA) to awaken consciousness of patients on 6 cases, 2 with brain trauma, one with aneurysm rupture, one with hemorrhagic stroke and two with hypoxic encephalopathy. The comatose duration ranged from 6 to 17 weeks. All patients underwent SPECT scan for cerebral perfusion evaluation and neurotransmitter quantification before and after the stimulation. The stimulation time lasted from 8 to 10 hours on daytime. The stimulation persisted for 3 months in all patients. Four patients recovered from the consciousness within 35 days. There was no obvious clinical improvement in two patients. Brain perfusion increased in all cases through the SPECT study after stimulation. The elevation of neurotransmitter in CSF was found in 5 out of the 6 cases. Median nerve stimulation elevates the cerebral blood flow and may influence the patient's consciousness. Young patients (<40 years old) had better results than old patients. The stimulation could be initiated if the patient's acute stage was over. In our series, although increase in cerebral blood flow was found in all cases, some patients did not regain consciousness.
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Affiliation(s)
- J T Liu
- Department of Neurosurgery, China Medical College Hospital, Taichung, Taiwan ROC.
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Sun W, Thomson W, Stewart D, Cooper E. Using E-Z vacuum manifold to isolate DNA for HLA molecular typing. Hum Immunol 2003. [DOI: 10.1016/j.humimm.2003.08.176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Vojdani A, Vojdani E, Cooper E. Antibodies to myelin basic protein, myelin oligodendrocytes peptides, alpha-beta-crystallin, lymphocyte activation and cytokine production in patients with multiple sclerosis. J Intern Med 2003; 254:363-74. [PMID: 12974875 DOI: 10.1046/j.1365-2796.2003.01203.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To measure neurone-specific humoral and cellular immune parameters in MRI-positive patients with multiple sclerosis (MS). BACKGROUND It has been postulated from animal models for MS and in situ evidence in MS patients that antibodies, activated T cells and proinflammatory cytokines are involved in the destruction of myelin sheaths and loss of oligodendrocytes in active areas. SUBJECTS AND METHODS Blood samples were obtained from 20 healthy control subjects and 20 patients with abnormal MRI and clinical diagnosis of MS. Sera were tested for levels of IgG, IgM and IgA against myelin basic protein (MBP), myelin oligodendrocyte glycoprotein (MOG) peptides, and a small heat-shock protein, alpha-beta-crystallin. Lymphocytes were isolated and cultured in the presence or absence of MBP, MOG peptides and alpha-beta-crystallin, measured for stimulated T cells, cytokine production and compared with controls. RESULTS Patients with MS showed the highest levels of IgG, IgM or IgA antibodies against one or all three tested antigens. Moreover, in the presence of MBP, MOG peptides or alpha-beta-crystallin, a significant percent- age of lymphocytes from MS patients underwent blast transformation, which resulted in high levels of interferon gamma (IFN-gamma), tumour necrosis factor alpha (TNF-alpha) and tumour necrosis factor beta (TNF-beta) production. Sensitivity of these assays was 60-80% and specificity, 65-70%. CONCLUSIONS Detection of antibodies against MBP, MOG peptides, alpha-beta-crystallin, lymphocyte stimulation and production of proinflammatory cytokines in response to these antigens could be used as surrogate markers for the confirmation of MS diagnosis. A combination of antibodies, lymphocyte activation or cytokine production with abnormal MRI may significantly increase the sensitivity and specificity of MS diagnosis.
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Affiliation(s)
- A Vojdani
- Immunosciences Lab., Inc., Beverly Hills Facility [corrected] USA.
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Keller MJ, Wheeler DG, Cooper E, Meier JL. Role of the human cytomegalovirus major immediate-early promoter's 19-base-pair-repeat cyclic AMP-response element in acutely infected cells. J Virol 2003; 77:6666-75. [PMID: 12767986 PMCID: PMC156166 DOI: 10.1128/jvi.77.12.6666-6675.2003] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [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: 01/30/2003] [Accepted: 03/18/2003] [Indexed: 01/08/2023] Open
Abstract
Prior studies have suggested a role of the five copies of the 19-bp-repeat cyclic AMP (cAMP)-response element (CRE) in major immediate-early (MIE) promoter activation, the rate-limiting step in human cytomegalovirus (HCMV) replication. We used two different HCMV genome modification strategies to test this hypothesis in acutely infected cells. We report the following: (i) the CREs do not govern basal levels of MIE promoter activity at a high or low multiplicity of infection (MOI) in human foreskin fibroblast (HFF)- or NTera2-derived neuronal cells; (ii) serum and virion components markedly increase MIE promoter-dependent transcription at a low multiplicity of infection (MOI), but this increase is not mediated by the CREs; (iii) forskolin stimulation of the cAMP signaling pathway induces a two- to threefold increase in MIE RNA levels in a CRE-specific manner at a low MOI in both HFF- and NTera2-derived neuronal cells; and (iv) the CREs do not regulate basal levels of HCMV DNA replication at a high or low MOI in HFF. Their presence does impart a forskolin-induced increase in viral DNA replication at a low MOI but only when basal levels of MIE promoter activity are experimentally diminished. In conclusion, the 19-bp-repeat CREs add to the robust MIE promoter activity that occurs in the acutely infected stimulated cells, although the CREs' greater role may be in other settings.
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Affiliation(s)
- M J Keller
- Department of Internal Medicine and the Helen C. Levitt Center for Viral Pathogenesis and Disease, University of Iowa Carver College of Medicine, Iowa City, Iowa 52242, USA
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Cooper E, Fraser M, Kwan J, Davidson D, O'Reilly M, Paull A. Shadowing—a new approach to infection control in the workplace. J Hosp Infect 2003. [DOI: 10.1053/jhin.2002.1268] [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: 11/11/2022]
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Abstract
Agrin is a nerve-derived factor that directs neuromuscular synapse formation, however its role in regulating interneuronal synaptogenesis is less clear. Here, we examine agrin's role in synapse formation between cholinergic preganglionic axons and sympathetic neurons in the superior cervical ganglion (SCG) using agrin-deficient mice. In dissociated cultures of SCG neurons, we found a significant decrease in the number of synapses with aggregates of presynaptic synaptophysin and postsynaptic neuronal acetylcholine receptor among agrin-deficient neurons as compared to wild-type neurons. Moreover, the levels of pre- and postsynaptic markers at the residual synapses in agrin-deficient SCG cultures were also reduced, and these defects were rescued by adding recombinant neural agrin to the cultures. Similarly, we observed a decreased matching of pre- and postsynaptic markers in SCG of agrin-deficient embryos, reflecting a decrease in the number of differentiated synapses in vivo. Finally, in electrophysiological experiments, we found that paired-pulse depression was more pronounced and posttetanic potentiation was significantly greater in agrin-deficient ganglia, indicating that synaptic transmission is also defective. Together, these findings indicate that neural agrin plays an organizing role in the formation and/or differentiation of interneuronal, cholinergic synapses.
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MESH Headings
- Action Potentials
- Agrin/genetics
- Agrin/physiology
- Animals
- Animals, Newborn
- Biomarkers/analysis
- Cell Count
- Cells, Cultured
- Cholinergic Fibers/metabolism
- Electrophysiology
- Ganglia, Sympathetic/cytology
- Ganglia, Sympathetic/growth & development
- Ganglia, Sympathetic/physiology
- Mice
- Mice, Inbred Strains
- Mice, Mutant Strains
- Rats
- Rats, Sprague-Dawley
- Receptors, Cholinergic/analysis
- Receptors, Cholinergic/metabolism
- Receptors, Nicotinic/analysis
- Superior Cervical Ganglion/cytology
- Synapses/chemistry
- Synapses/physiology
- Synapses/ultrastructure
- Synaptophysin/analysis
- Synaptophysin/metabolism
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Affiliation(s)
- Jacinthe Gingras
- Department of Neurology and Neurosurgery, Center for Research in Neuroscience, The Research Institute of the McGill University Health Centre, 1650 Cedar Avenue, Montreal, Quebec H3G 1A4, Canada
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Peri CV, Shaffrey ME, Farace E, Cooper E, Alves WM, Cooper JB, Young JS, Jane JA. Pilot study of electrical stimulation on median nerve in comatose severe brain injured patients: 3-month outcome. Brain Inj 2001; 15:903-10. [PMID: 11595086 DOI: 10.1080/02699050110065709] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
PRIMARY OBJECTIVE To determine if electrical stimulation (ES) benefits (waking time, 3-month outcomes) treated coma patients. RESEARCH DESIGN Double blind randomized-controlled study. METHODS AND PROCEDURES Ten coma patients; six treatment and four controls, using the 'Respond Select' by EMPI. EXPERIMENTAL INTERVENTIONS Treatment group received radial nerve ES applied in 300 ms intermittent pulses at 40 Hz, 15-20m A 8 hours a day up to 14 days of coma; control group received sham stimulation. MAIN OUTCOMES AND RESULTS ES group emerged from coma mean 2 days earlier than controls, although this result was not statistically significant. At 3 months post-injury, there was no group difference in Glasgow Outcome Scale, although the ES group had improved function over controls as measured by the FIM/FAM (mean of 114 and 64.5, respectively, n.s.). CONCLUSIONS These data show an interesting trend, although statistical power was limited in this small pilot study, suggesting the need for a larger trial.
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Affiliation(s)
- C V Peri
- University of Virginia, Charlottesville, VA 22908, USA
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Cooper E, Paull A. Occupational exposure: there for your protection. Aust Nurs J 2001; 9:35. [PMID: 11908118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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Abstract
Activity-dependent changes in gene expression involving the transcription factor cAMP-response element-binding protein (CREB) occur in learning and memory, pain, and drug addiction. This mechanism may also be important for cytomegaloviral infections of the brain. The human cytomegalovirus major immediate-early promoter/enhancer (hCMV promoter), rate-limiting for productive cytomegalovirus infection, contains five cAMP-response elements (CREs). Indirect evidence suggests that this promoter does not function in unstimulated neurons. Here we test the hypothesis that expression from the hCMV promoter in neurons is induced by membrane depolarization. For these experiments, we infected cultured sympathetic and hippocampal neurons with hCMV-green fluorescent protein (GFP) promoter/reporter constructs using adenoviral gene transfer techniques and measured transgene expression by quantifying GFP fluorescence and GFP mRNA levels. We found that depolarization up-regulates promoter activity by >90-fold. Moreover, our results from pharmacological experiments suggest that this induction occurred through a CREB-dependent pathway. Importantly, site-directed mutagenesis of all five CREs in the promoter blocked this up-regulation almost completely, whereas mutating four of them had no effect. We conclude that the hCMV promoter acts as a molecular switch in neurons and is strongly induced by membrane depolarization, neuronal activity, or other stimuli that activate CREB. These results may provide insight into molecular mechanisms of cytomegalovirus-related diseases of the brain.
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Affiliation(s)
- D G Wheeler
- Department of Physiology, McGill University, Montréal, Québec H3G 1Y6, Canada
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