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Gilly WF, Teal P, Graves EE, Lo J, Schneider MB, Zasio R, Adler JR. Effects of Focal Ionizing Radiation of the Squid Stellate Ganglion on Synaptic and Axonal Transmission in the Giant-Fiber Pathway. Cureus 2021; 13:e13110. [PMID: 33692914 PMCID: PMC7938441 DOI: 10.7759/cureus.13110] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Ionizing radiation is clinically used to treat neurological problems and reduce pathological levels of neural activity in the brain, but its cellular-level mechanisms are not well understood. Although spontaneous and stimulated synaptic activity has been produced in rodents by clinically and environmentally relevant doses of radiation, the effects on basic excitability properties of neurons have seldom been reported. This study examined the effects of focused ionizing radiation on synaptic transmission and action potential generation in the squid giant-fiber system, which includes the giant synapse between a secondary interneuron and the tertiary giant motor axons. Radiation of 140-300 Gy was delivered to a stellate ganglion of a living squid over several minutes, with the contralateral stellate ganglion serving as an internal control. No qualitative changes in the efficacy of synaptic transmission were noted in conjunction with stimulation of the input to the giant synapse, although in one irradiated ganglion, the refractory period increased from about 5 ms to more than 45 seconds. Small but significant changes in the action potential recorded from the giant motor axon in response to electrical stimulation were associated with an increased maximum rate of fall and a shortened action potential duration. Other action-potential parameters, including resting potential, overshoot, the maximum rate of the rise, and the refractory period were not significantly changed. Attempts to account for the observed changes in the action potential were carried through a Hodgkin-Huxley model of the action potential. This approach suggests that an increase in the maximum voltage-gated potassium conductance of about 50% mimics the action potential shortening and increased rate of fall that was experimentally observed. We propose that such an effect could result from phosphorylation of squid potassium channels.
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Affiliation(s)
- William F Gilly
- Biology, Hopkins Marine Station, Stanford University, Pacific Grove, USA
| | - P Teal
- Biology, Hopkins Marine Station, Stanford University, Pacific Grove, USA
| | - Edward E Graves
- Radiation Oncology, Stanford University School of Medicine, Stanford, USA
| | - Jackei Lo
- Radiation Oncology, Stanford Health Care, Stanford, USA
| | - M Bret Schneider
- Neurosurgery, Stanford University School of Medicine, Stanford, USA.,Psychiatry, Stanford University School of Medicine, Stanford, USA
| | - Reese Zasio
- Veterinary Service Center, Stanford University School of Medicine, Stanford, USA
| | - John R Adler
- Radiation Oncology, Stanford University Medical Center, Stanford, USA.,Neurosurgery, Stanford University School of Medicine, Stanford, USA
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2
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Hametner C, MacIsaac RL, Kellert L, Abdul-Rahim AH, Ringleb PA, Lees KR, Alexandrov A, Bath P, Bluhmki E, Bornstein N, Chen C, Claesson L, Davis S, Donnan G, Diener H, Fisher M, Ginsberg M, Gregson B, Grotta J, Hacke W, Hennerici M, Hommel M, Kaste M, Lyden P, Marler J, Muir K, Venketasubramanian N, Sacco R, Shuaib A, Teal P, Wahlgren N, Warach S, Weimar C. Sex and Stroke in Thrombolyzed Patients and Controls. Stroke 2017; 48:367-374. [DOI: 10.1161/strokeaha.116.014323] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 09/02/2016] [Accepted: 09/19/2016] [Indexed: 01/22/2023]
Abstract
Background and Purpose—
We hypothesized that any sex-related difference in outcome poststroke is explained by other prognostic factors and that the response to intravenous recombinant tissue-type plasminogen activator (r-tPA) is equal in males and females after adjustment for such factors.
Methods—
We accessed an independent collection of randomized clinical trials—the VISTA (Virtual International Stroke Trials Archive). Data were preprocessed by selecting complete cases (n=8028) and matching females to males (coarsened exact matching, n=4575, 24.3% r-tPA). Outcome was assessed by the 7-point modified Rankin Scale (mRS) measured at 90 days after ischemic stroke. Relationship among variables was estimated by adjusted regression analysis.
Results—
In nonthrombolyzed patients, ordinal analysis of mRS adjusting for stroke- and sex-related prognostic factors suggested comparable outcomes for females and males (odds ratio, 0.96; 95% confidence interval, 0.85–1.06). Females responded comparably to r-tPA as did males, irrespective of the outcome definition of mRS (ordinal:
P
Interaction
=0.46, relative excess risk because of interaction=0). The number needed to treat was 6.8 and 11.2 for 1 female to achieve mRS score of 0 to 2 and 0 to 1, which was highly congruent with males. Analysis for a nonlinear variation of age-by-sex revealed a good outcome for females <45 years with significant disadvantage thereafter (mRS score of 0–2:
P
Interaction
=0.004). No relationship between sex, r-tPA, and bleeding complications was evident.
Conclusions—
Functional outcome (mRS) without r-tPA was overall similar between the sexes, as was the response to r-tPA. Nonlinear sex-by-age interaction improved estimates of functional independence; this should be considered in sex-related studies in stroke.
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Affiliation(s)
- Christian Hametner
- From the Department of Neurology, Division of Vascular Neurology, University of Heidelberg, Germany (C.H., L.K., P.A.R.); Queen Elizabeth University Hospital (R.L.M., A.H.A.-R.) and BHF Cardiovascular Research Centre (K.R.L.), Institute of Cardiovascular and Medical Sciences, University of Glasgow, United Kingdom; and Department of Neurology, Ludwig-Maximilians-University Munich, Germany (L.K.)
| | - Rachael L. MacIsaac
- From the Department of Neurology, Division of Vascular Neurology, University of Heidelberg, Germany (C.H., L.K., P.A.R.); Queen Elizabeth University Hospital (R.L.M., A.H.A.-R.) and BHF Cardiovascular Research Centre (K.R.L.), Institute of Cardiovascular and Medical Sciences, University of Glasgow, United Kingdom; and Department of Neurology, Ludwig-Maximilians-University Munich, Germany (L.K.)
| | - Lars Kellert
- From the Department of Neurology, Division of Vascular Neurology, University of Heidelberg, Germany (C.H., L.K., P.A.R.); Queen Elizabeth University Hospital (R.L.M., A.H.A.-R.) and BHF Cardiovascular Research Centre (K.R.L.), Institute of Cardiovascular and Medical Sciences, University of Glasgow, United Kingdom; and Department of Neurology, Ludwig-Maximilians-University Munich, Germany (L.K.)
| | - Azmil H. Abdul-Rahim
- From the Department of Neurology, Division of Vascular Neurology, University of Heidelberg, Germany (C.H., L.K., P.A.R.); Queen Elizabeth University Hospital (R.L.M., A.H.A.-R.) and BHF Cardiovascular Research Centre (K.R.L.), Institute of Cardiovascular and Medical Sciences, University of Glasgow, United Kingdom; and Department of Neurology, Ludwig-Maximilians-University Munich, Germany (L.K.)
| | - Peter A. Ringleb
- From the Department of Neurology, Division of Vascular Neurology, University of Heidelberg, Germany (C.H., L.K., P.A.R.); Queen Elizabeth University Hospital (R.L.M., A.H.A.-R.) and BHF Cardiovascular Research Centre (K.R.L.), Institute of Cardiovascular and Medical Sciences, University of Glasgow, United Kingdom; and Department of Neurology, Ludwig-Maximilians-University Munich, Germany (L.K.)
| | - Kennedy R. Lees
- From the Department of Neurology, Division of Vascular Neurology, University of Heidelberg, Germany (C.H., L.K., P.A.R.); Queen Elizabeth University Hospital (R.L.M., A.H.A.-R.) and BHF Cardiovascular Research Centre (K.R.L.), Institute of Cardiovascular and Medical Sciences, University of Glasgow, United Kingdom; and Department of Neurology, Ludwig-Maximilians-University Munich, Germany (L.K.)
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3
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Sykora M, Siarnik P, Diedler J, Lees K, Alexandrov A, Bath P, Bluhmki E, Bornstein N, Claesson L, Davis S, Donnan G, Diener HC, Fisher M, Ginsberg M, Gregson B, Grotta J, Hacke W, Hennerici M, Hommel M, Kaste M, Lyden P, Marler J, Muir K, Sacco R, Shuaib A, Teal P, Wahlgren N, Warach S, Weimar C. β-Blockers, Pneumonia, and Outcome After Ischemic Stroke. Stroke 2015; 46:1269-74. [DOI: 10.1161/strokeaha.114.008260] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 01/21/2015] [Indexed: 02/02/2023]
Abstract
Background and Purpose—
Increased sympathetic drive after stroke is involved in the pathophysiology of several complications including poststroke immunudepression. β-Blocker (BB) therapy has been suggested to have neuroprotective properties and to decrease infectious complications after stroke. We aimed to examine the effects of random pre- and on-stroke BB exposure on mortality, functional outcome, and occurrence of pneumonia after ischemic stroke.
Methods—
Data including standard demographic and clinical variables as well as prestroke and on-stroke antihypertensive medication, incidence of pneumonia, functional outcome defined using modified Rankin Scale and mortality at 3 months were extracted from the Virtual International Stroke Trials Archive. For statistical analysis multivariable Poisson regression was used.
Results—
In total, 5212 patients were analyzed. A total of 1155 (22.2%) patients were treated with BB before stroke onset and 244 (4.7%) patients were newly started with BB in the acute phase of stroke. Mortality was 17.5%, favorable outcome (defined as modified Rankin Scale, 0–2) occurred in 58.2% and pneumonia in 8.2% of patients. Prestroke BB showed no association with mortality. On-stroke BB was associated with reduced mortality (adjusted risk ratio, 0.63; 95% confidence interval, 0.42–0.96). Neither prestroke BB nor on-stroke BB showed an association with functional outcome. Both prestroke and on-stroke BB were associated with reduced frequency of pneumonia (adjusted risk ratio, 0.77; 95% confidence interval, 0.6–0.98 and risk ratio, 0.49; 95% confidence interval, 0.25–0.95).
Conclusions—
In this large nonrandomized comparison, on-stroke BB was associated with reduced mortality. Prestroke and on-stroke BB were inversely associated with incidence of nosocomial pneumonia. Randomized trials investigating the potential of β-blockade in acute stroke may be warranted.
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Affiliation(s)
- Marek Sykora
- From the Department of Neurology, University of Heidelberg, Heidelberg, Germany (M.S., J.D.); Department of Neurology, Comenius University, Bratislava, Slovakia (P.S.); and Department of Neurology, University of Tübingen, Tübingen, Germany (J.D.)
| | - Pavel Siarnik
- From the Department of Neurology, University of Heidelberg, Heidelberg, Germany (M.S., J.D.); Department of Neurology, Comenius University, Bratislava, Slovakia (P.S.); and Department of Neurology, University of Tübingen, Tübingen, Germany (J.D.)
| | - Jennifer Diedler
- From the Department of Neurology, University of Heidelberg, Heidelberg, Germany (M.S., J.D.); Department of Neurology, Comenius University, Bratislava, Slovakia (P.S.); and Department of Neurology, University of Tübingen, Tübingen, Germany (J.D.)
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4
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Gladstone DJ, Dorian P, Spring M, Panzov V, Mamdani M, Healey JS, Thorpe KE, Aviv R, Boyle K, Blakely J, Cote R, Hall J, Kapral M, Kozlowski N, Laupacis A, O’Donnell M, Sabihuddin K, Sharma M, Shuaib A, Vaid H, Pinter A, Abootalebi S, Chan R, Crann S, Fleming L, Frank C, Hachinski V, Hesser K, Kumar B, Soros P, Wright M, Basile V, Boyle K, Hopyan J, Rajmohan Y, Swartz R, Vaid H, Valencia G, Ween J, Aram H, Barber P, Coutts S, Demchuk A, Fischer K, Hill M, Klein G, Kenney C, Menon B, McClelland M, Russell A, Ryckborst K, Stys P, Smith E, Watson T, Chacko S, Sahlas D, Sancan J, Côté R, Durcan L, Ehrensperger E, Minuk J, Wein T, Wadup L, Asdaghi N, Beckman J, Esplana N, Masigan P, Murphy C, Tang E, Teal P, Villaluna K, Woolfenden A, Yip S, Bussière M, Dowlatshahi D, Sharma M, Stotts G, Robert S, Ford K, Hackam D, Miners L, Mabb T, Spence JD, Buck B, Griffin-Stead T, Jassal R, Siddiqui M, Hache A, Lessard C, Lebel F, Mackey A, Verreault S, Astorga C, Casaubon LK, del Campo M, Jaigobin C, Kalman L, Silver FL, Atkins L, Coles K, Penn A, Sargent R, Walter C, Gable Y, Kadribasic N, Schwindt B, Shuaib A, Kostyrko P, Selchen D, Saposnik G, Christie P, Jin A, Hicklin D, Howse D, Edwards E, Jaspers S, Sher F, Stoger S, Crisp D, Dhanani A, John V, Levitan M, Mehdiratta M, Wong D. Atrial Premature Beats Predict Atrial Fibrillation in Cryptogenic Stroke. Stroke 2015; 46:936-41. [DOI: 10.1161/strokeaha.115.008714] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- David J. Gladstone
- From the Division of Neurology (D.J.G.), Department of Medicine (D.J.G., P.D., M.S., M.M.), and Dalla Lana School of Public Health (K.E.T.), University of Toronto, Toronto, Ontario, Canada; University of Toronto Stroke Program, Toronto, Ontario, Canada (D.J.G.); Division of Neurology, Department of Medicine, and the Hurvitz Brain Sciences Program, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, Ontario, Canada (D.J.G.); Heart and Stroke Foundation Canadian Partnership for
| | - Paul Dorian
- From the Division of Neurology (D.J.G.), Department of Medicine (D.J.G., P.D., M.S., M.M.), and Dalla Lana School of Public Health (K.E.T.), University of Toronto, Toronto, Ontario, Canada; University of Toronto Stroke Program, Toronto, Ontario, Canada (D.J.G.); Division of Neurology, Department of Medicine, and the Hurvitz Brain Sciences Program, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, Ontario, Canada (D.J.G.); Heart and Stroke Foundation Canadian Partnership for
| | - Melanie Spring
- From the Division of Neurology (D.J.G.), Department of Medicine (D.J.G., P.D., M.S., M.M.), and Dalla Lana School of Public Health (K.E.T.), University of Toronto, Toronto, Ontario, Canada; University of Toronto Stroke Program, Toronto, Ontario, Canada (D.J.G.); Division of Neurology, Department of Medicine, and the Hurvitz Brain Sciences Program, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, Ontario, Canada (D.J.G.); Heart and Stroke Foundation Canadian Partnership for
| | - Val Panzov
- From the Division of Neurology (D.J.G.), Department of Medicine (D.J.G., P.D., M.S., M.M.), and Dalla Lana School of Public Health (K.E.T.), University of Toronto, Toronto, Ontario, Canada; University of Toronto Stroke Program, Toronto, Ontario, Canada (D.J.G.); Division of Neurology, Department of Medicine, and the Hurvitz Brain Sciences Program, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, Ontario, Canada (D.J.G.); Heart and Stroke Foundation Canadian Partnership for
| | - Muhammad Mamdani
- From the Division of Neurology (D.J.G.), Department of Medicine (D.J.G., P.D., M.S., M.M.), and Dalla Lana School of Public Health (K.E.T.), University of Toronto, Toronto, Ontario, Canada; University of Toronto Stroke Program, Toronto, Ontario, Canada (D.J.G.); Division of Neurology, Department of Medicine, and the Hurvitz Brain Sciences Program, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, Ontario, Canada (D.J.G.); Heart and Stroke Foundation Canadian Partnership for
| | - Jeff S. Healey
- From the Division of Neurology (D.J.G.), Department of Medicine (D.J.G., P.D., M.S., M.M.), and Dalla Lana School of Public Health (K.E.T.), University of Toronto, Toronto, Ontario, Canada; University of Toronto Stroke Program, Toronto, Ontario, Canada (D.J.G.); Division of Neurology, Department of Medicine, and the Hurvitz Brain Sciences Program, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, Ontario, Canada (D.J.G.); Heart and Stroke Foundation Canadian Partnership for
| | - Kevin E. Thorpe
- From the Division of Neurology (D.J.G.), Department of Medicine (D.J.G., P.D., M.S., M.M.), and Dalla Lana School of Public Health (K.E.T.), University of Toronto, Toronto, Ontario, Canada; University of Toronto Stroke Program, Toronto, Ontario, Canada (D.J.G.); Division of Neurology, Department of Medicine, and the Hurvitz Brain Sciences Program, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, Ontario, Canada (D.J.G.); Heart and Stroke Foundation Canadian Partnership for
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - R. Chan
- London Health Sciences Centre; London, Ontario
| | - S. Crann
- London Health Sciences Centre; London, Ontario
| | - L. Fleming
- London Health Sciences Centre; London, Ontario
| | - C. Frank
- London Health Sciences Centre; London, Ontario
| | | | - K. Hesser
- London Health Sciences Centre; London, Ontario
| | - B.S. Kumar
- London Health Sciences Centre; London, Ontario
| | - P. Soros
- London Health Sciences Centre; London, Ontario
| | - M. Wright
- London Health Sciences Centre; London, Ontario
| | - V. Basile
- Sunnybrook Health Sciences Centre; Toronto, Ontario
| | - K. Boyle
- Sunnybrook Health Sciences Centre; Toronto, Ontario
| | - J. Hopyan
- Sunnybrook Health Sciences Centre; Toronto, Ontario
| | - Y. Rajmohan
- Sunnybrook Health Sciences Centre; Toronto, Ontario
| | - R. Swartz
- Sunnybrook Health Sciences Centre; Toronto, Ontario
| | - H. Vaid
- Sunnybrook Health Sciences Centre; Toronto, Ontario
| | - G. Valencia
- Sunnybrook Health Sciences Centre; Toronto, Ontario
| | - J. Ween
- Sunnybrook Health Sciences Centre; Toronto, Ontario
| | - H. Aram
- Foothills Hospital; Calgary, Alberta
| | | | - S. Coutts
- Foothills Hospital; Calgary, Alberta
| | | | | | - M.D. Hill
- Foothills Hospital; Calgary, Alberta
| | - G. Klein
- Foothills Hospital; Calgary, Alberta
| | - C. Kenney
- Foothills Hospital; Calgary, Alberta
| | - B. Menon
- Foothills Hospital; Calgary, Alberta
| | | | | | | | - P. Stys
- Foothills Hospital; Calgary, Alberta
| | | | | | - S. Chacko
- Hamilton Health Sciences Centre; Hamilton, Ontario
| | - D. Sahlas
- Hamilton Health Sciences Centre; Hamilton, Ontario
| | - J. Sancan
- Hamilton Health Sciences Centre; Hamilton, Ontario
| | - R. Côté
- Montreal General Hospital; Montreal, Québec
| | - L. Durcan
- Montreal General Hospital; Montreal, Québec
| | | | - J. Minuk
- Montreal General Hospital; Montreal, Québec
| | - T. Wein
- Montreal General Hospital; Montreal, Québec
| | - L. Wadup
- Montreal General Hospital; Montreal, Québec
| | - N. Asdaghi
- Vancouver Hospital and Health Sciences Centre; Vancouver, British Columbia
| | - J. Beckman
- Vancouver Hospital and Health Sciences Centre; Vancouver, British Columbia
| | - N. Esplana
- Vancouver Hospital and Health Sciences Centre; Vancouver, British Columbia
| | - P. Masigan
- Vancouver Hospital and Health Sciences Centre; Vancouver, British Columbia
| | - C. Murphy
- Vancouver Hospital and Health Sciences Centre; Vancouver, British Columbia
| | - E. Tang
- Vancouver Hospital and Health Sciences Centre; Vancouver, British Columbia
| | - P. Teal
- Vancouver Hospital and Health Sciences Centre; Vancouver, British Columbia
| | - K. Villaluna
- Vancouver Hospital and Health Sciences Centre; Vancouver, British Columbia
| | - A. Woolfenden
- Vancouver Hospital and Health Sciences Centre; Vancouver, British Columbia
| | - S. Yip
- Vancouver Hospital and Health Sciences Centre; Vancouver, British Columbia
| | | | | | - M. Sharma
- The Ottawa Hospital; Ottawa, Ontario
| | - G. Stotts
- The Ottawa Hospital; Ottawa, Ontario
| | - S. Robert
- The Ottawa Hospital; Ottawa, Ontario
| | - K. Ford
- Stroke Prevention & Atherosclerosis Research Centre, Robarts Research Institute; London, Ontario
| | - D. Hackam
- Stroke Prevention & Atherosclerosis Research Centre, Robarts Research Institute; London, Ontario
| | - L. Miners
- Stroke Prevention & Atherosclerosis Research Centre, Robarts Research Institute; London, Ontario
| | - T. Mabb
- Stroke Prevention & Atherosclerosis Research Centre, Robarts Research Institute; London, Ontario
| | - J. D. Spence
- Stroke Prevention & Atherosclerosis Research Centre, Robarts Research Institute; London, Ontario
| | - B. Buck
- Grey Nuns Hospital; Edmonton Alberta
| | | | - R. Jassal
- Grey Nuns Hospital; Edmonton Alberta
| | | | - A. Hache
- Centre Hospitalier Affilié Universitaire de Québec: Hôpital de l’Enfant-Jesus; Québec, Québec
| | - C. Lessard
- Centre Hospitalier Affilié Universitaire de Québec: Hôpital de l’Enfant-Jesus; Québec, Québec
| | - F. Lebel
- Centre Hospitalier Affilié Universitaire de Québec: Hôpital de l’Enfant-Jesus; Québec, Québec
| | - A. Mackey
- Centre Hospitalier Affilié Universitaire de Québec: Hôpital de l’Enfant-Jesus; Québec, Québec
| | - S. Verreault
- Centre Hospitalier Affilié Universitaire de Québec: Hôpital de l’Enfant-Jesus; Québec, Québec
| | - C. Astorga
- University Health Network; Toronto, Ontario
| | | | | | | | - L. Kalman
- University Health Network; Toronto, Ontario
| | - FL Silver
- University Health Network; Toronto, Ontario
| | - L. Atkins
- Vancouver Island Health Authority; Victoria, British Columbia
| | - K. Coles
- Vancouver Island Health Authority; Victoria, British Columbia
| | - A. Penn
- Vancouver Island Health Authority; Victoria, British Columbia
| | - R. Sargent
- Vancouver Island Health Authority; Victoria, British Columbia
| | - C. Walter
- Vancouver Island Health Authority; Victoria, British Columbia
| | - Y. Gable
- Mackenzie Health Sciences Centre; Edmonton, Alberta
| | | | - B. Schwindt
- Mackenzie Health Sciences Centre; Edmonton, Alberta
| | - A. Shuaib
- Mackenzie Health Sciences Centre; Edmonton, Alberta
| | | | - D. Selchen
- St. Michael’s Hospital; Toronto, Ontario
| | | | - P. Christie
- Kingston General Hospital; Kingston, Ontario
| | - A. Jin
- Kingston General Hospital; Kingston, Ontario
| | - D. Hicklin
- Thunder Bay Regional Health Sciences Centre; Thunder Bay, Ontario
| | - D. Howse
- Thunder Bay Regional Health Sciences Centre; Thunder Bay, Ontario
| | - E. Edwards
- Thunder Bay Regional Health Sciences Centre; Thunder Bay, Ontario
| | - S. Jaspers
- Thunder Bay Regional Health Sciences Centre; Thunder Bay, Ontario
| | - F. Sher
- Thunder Bay Regional Health Sciences Centre; Thunder Bay, Ontario
| | - S. Stoger
- Thunder Bay Regional Health Sciences Centre; Thunder Bay, Ontario
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5
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Saleem S, Teal P, Kleijn WB, O'Donnell T, Witter T, Tzeng Y‐C. Non‐linear Relationships between Blood Pressure and Cerebral Blood Flow. FASEB J 2015. [DOI: 10.1096/fasebj.29.1_supplement.833.3] [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)
- Saqib Saleem
- ECS Victoria University of WellingtonNew Zealand
- CTP University of OtagoNew Zealand
| | - P. Teal
- ECS Victoria University of WellingtonNew Zealand
| | - W B. Kleijn
- ECS Victoria University of WellingtonNew Zealand
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6
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Abdul-Rahim AH, Fulton RL, Sucharew H, Kleindorfer D, Khatri P, Broderick JP, Lees KR, Alexandrov A, Bath P, Bluhmki E, Bornstein N, Claesson L, Curram J, Davis S, Donnan G, Diener H, Fisher M, Ginsberg M, Gregson B, Grotta J, Hacke W, Hennerici M, Hommel M, Kaste M, Lyden P, Marler J, Muir K, Sacco R, Shuaib A, Teal P, Wahlgren N, Warach S, Weimar C. National Institutes of Health Stroke Scale Item Profiles as Predictor of Patient Outcome. Stroke 2015; 46:395-400. [DOI: 10.1161/strokeaha.114.006837] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Azmil H. Abdul-Rahim
- From the Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (A.H.A.-R., R.L.F., K.R.L.); Division of Biostatistics and Epidemiology, Cincinnati Children’s Hospital Medical Centre, OH (H.S.); Department of Neurology, University of Cincinnati College of Medicine, OH (D.K., P.K., J.P.B.)
| | - Rachael L. Fulton
- From the Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (A.H.A.-R., R.L.F., K.R.L.); Division of Biostatistics and Epidemiology, Cincinnati Children’s Hospital Medical Centre, OH (H.S.); Department of Neurology, University of Cincinnati College of Medicine, OH (D.K., P.K., J.P.B.)
| | - Heidi Sucharew
- From the Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (A.H.A.-R., R.L.F., K.R.L.); Division of Biostatistics and Epidemiology, Cincinnati Children’s Hospital Medical Centre, OH (H.S.); Department of Neurology, University of Cincinnati College of Medicine, OH (D.K., P.K., J.P.B.)
| | - Dawn Kleindorfer
- From the Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (A.H.A.-R., R.L.F., K.R.L.); Division of Biostatistics and Epidemiology, Cincinnati Children’s Hospital Medical Centre, OH (H.S.); Department of Neurology, University of Cincinnati College of Medicine, OH (D.K., P.K., J.P.B.)
| | - Pooja Khatri
- From the Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (A.H.A.-R., R.L.F., K.R.L.); Division of Biostatistics and Epidemiology, Cincinnati Children’s Hospital Medical Centre, OH (H.S.); Department of Neurology, University of Cincinnati College of Medicine, OH (D.K., P.K., J.P.B.)
| | - Joseph P. Broderick
- From the Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (A.H.A.-R., R.L.F., K.R.L.); Division of Biostatistics and Epidemiology, Cincinnati Children’s Hospital Medical Centre, OH (H.S.); Department of Neurology, University of Cincinnati College of Medicine, OH (D.K., P.K., J.P.B.)
| | - Kennedy R. Lees
- From the Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (A.H.A.-R., R.L.F., K.R.L.); Division of Biostatistics and Epidemiology, Cincinnati Children’s Hospital Medical Centre, OH (H.S.); Department of Neurology, University of Cincinnati College of Medicine, OH (D.K., P.K., J.P.B.)
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7
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Amsalem E, Teal P, Grozinger CM, Hefetz A. Precocene-I inhibits juvenile hormone biosynthesis, ovarian activation, aggression and alters sterility signal production in bumble bee (Bombus terrestris) workers. ACTA ACUST UNITED AC 2014; 217:3178-85. [PMID: 25013106 DOI: 10.1242/jeb.107250] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Juvenile hormone (JH) is an important regulator of development and physiology in insects. While in many insect species, including bumble bees, JH functions as gonadotropin in adults, in some highly eusocial insects its role has shifted to regulate social behavior including division of labor, dominance and aggression. Studying JH functions across social insect species is important for understanding the evolution of sociality; however, these studies have been limited because of the inability to reduce JH levels without surgically removing its glandular source, the corpora allata. Precocene is known to inhibit JH biosynthesis in several non-social insects, but has been poorly studied in social insects. Here, we tested whether precocene-I can effectively reduce JH levels in Bombus terrestris workers, and examined its effects on their physiology and behavior. Precocene-I treatment of three-worker groups decreased JH titer and ovarian activation, irrespective of the bees' dominance rank within the group, and was remedied by JH replacement therapy. Precocene-I also decreased aggressiveness and increased ester-sterility signal production; these changes were rank-dependent, and affected mainly the most reproductive and the least aggressive workers, respectively, and could not be remedied by JH replacement therapy. These results clearly confirm the role of JH as a gonadotropin and mediator of aggression in B. terrestris, and indicate that JH effects are associated with worker dominance rank. The ability to chemically reduce JH titer provides us with a non-intrusive method to probe the evolutionary changes associated with JH and the hormonal mechanisms that are associated with reproduction and behavior in social insects.
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Affiliation(s)
- E Amsalem
- Department of Entomology, Center for Pollinator Research, Center for Chemical Ecology, The Pennsylvania State University, University Park, PA 16802, USA
| | - P Teal
- Chemistry Research Unit, 1600-1700 SW, 23rd Drive, Gainesville, FL 32608, USA
| | - C M Grozinger
- Department of Entomology, Center for Pollinator Research, Center for Chemical Ecology, The Pennsylvania State University, University Park, PA 16802, USA
| | - A Hefetz
- Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
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Gladstone DJ, Spring M, Dorian P, Panzov V, Thorpe KE, Hall J, Vaid H, O'Donnell M, Laupacis A, Côté R, Sharma M, Blakely JA, Shuaib A, Hachinski V, Coutts SB, Sahlas DJ, Teal P, Yip S, Spence JD, Buck B, Verreault S, Casaubon LK, Penn A, Selchen D, Jin A, Howse D, Mehdiratta M, Boyle K, Aviv R, Kapral MK, Mamdani M. Atrial fibrillation in patients with cryptogenic stroke. N Engl J Med 2014; 370:2467-77. [PMID: 24963566 DOI: 10.1056/nejmoa1311376] [Citation(s) in RCA: 861] [Impact Index Per Article: 86.1] [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: 01/07/2023]
Abstract
BACKGROUND Atrial fibrillation is a leading preventable cause of recurrent stroke for which early detection and treatment are critical. However, paroxysmal atrial fibrillation is often asymptomatic and likely to go undetected and untreated in the routine care of patients with ischemic stroke or transient ischemic attack (TIA). METHODS We randomly assigned 572 patients 55 years of age or older, without known atrial fibrillation, who had had a cryptogenic ischemic stroke or TIA within the previous 6 months (cause undetermined after standard tests, including 24-hour electrocardiography [ECG]), to undergo additional noninvasive ambulatory ECG monitoring with either a 30-day event-triggered recorder (intervention group) or a conventional 24-hour monitor (control group). The primary outcome was newly detected atrial fibrillation lasting 30 seconds or longer within 90 days after randomization. Secondary outcomes included episodes of atrial fibrillation lasting 2.5 minutes or longer and anticoagulation status at 90 days. RESULTS Atrial fibrillation lasting 30 seconds or longer was detected in 45 of 280 patients (16.1%) in the intervention group, as compared with 9 of 277 (3.2%) in the control group (absolute difference, 12.9 percentage points; 95% confidence interval [CI], 8.0 to 17.6; P<0.001; number needed to screen, 8). Atrial fibrillation lasting 2.5 minutes or longer was present in 28 of 284 patients (9.9%) in the intervention group, as compared with 7 of 277 (2.5%) in the control group (absolute difference, 7.4 percentage points; 95% CI, 3.4 to 11.3; P<0.001). By 90 days, oral anticoagulant therapy had been prescribed for more patients in the intervention group than in the control group (52 of 280 patients [18.6%] vs. 31 of 279 [11.1%]; absolute difference, 7.5 percentage points; 95% CI, 1.6 to 13.3; P=0.01). CONCLUSIONS Among patients with a recent cryptogenic stroke or TIA who were 55 years of age or older, paroxysmal atrial fibrillation was common. Noninvasive ambulatory ECG monitoring for a target of 30 days significantly improved the detection of atrial fibrillation by a factor of more than five and nearly doubled the rate of anticoagulant treatment, as compared with the standard practice of short-duration ECG monitoring. (Funded by the Canadian Stroke Network and others; EMBRACE ClinicalTrials.gov number, NCT00846924.).
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Affiliation(s)
- David J Gladstone
- From the Division of Neurology (D.J.G.), Department of Medicine (D.J.G., P.D., A.L., M.S., J.A.B., L.K.C., D.S., M. Mehdiratta, K.B., M.K.K.), and Dalla Lana School of Public Health (K.E.T.), University of Toronto, the University of Toronto Stroke Program (D.J.G.), Division of Neurology, Department of Medicine, and Brain Sciences Program, Sunnybrook Health Sciences Centre and Sunnybrook Research Institute (D.J.G., R.A.), the Heart and Stroke Foundation Canadian Partnership for Stroke Recovery (D.J.G.), and the Applied Health Research Centre, Li Ka Shing Knowledge Institute of St. Michael's Hospital (V.P., K.E.T., J.H., H.V., A.L., M. Mamdani), Toronto, McMaster University, Hamilton, ON (M.S., D.J.S.), McGill University, Montreal (R.C.), University of Alberta, Edmonton (A.S., B.B.), Western University, London, ON (V.H., J.D.S.), Department of Clinical Neurosciences and Radiology, Hotchkiss Brain Institute, University of Calgary, Calgary, AB (S.B.C.), University of British Columbia, Vancouver (P.T., S.Y.), Queen's University, Kingston, ON (A.J.), Thunder Bay Regional Health Sciences Centre, Thunder Bay, ON (D.H.), Université Laval, Quebec City (S.V.), and Vancouver Island Health Research Centre, Victoria, BC (A.P.) - all in Canada; and the National University of Ireland, Galway (M.O.)
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9
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Flint AC, Faigeles BS, Cullen SP, Kamel H, Rao VA, Gupta R, Smith WS, Bath PM, Donnan GA, Lees K, Alexandrov A, Bath P, Bluhmki E, Bornstein N, Claesson L, Davis S, Donnan G, Diener H, Fisher M, Gregson B, Grotta J, Hacke W, Hennerici M, Hommel M, Kaste M, Lyden P, Marler J, Muir K, Sacco R, Shuaib A, Teal P, Wahlgren N, Warach S, Weimar C. THRIVE Score Predicts Ischemic Stroke Outcomes and Thrombolytic Hemorrhage Risk in VISTA. Stroke 2013; 44:3365-9. [DOI: 10.1161/strokeaha.113.002794] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Background and Purpose—
In previous studies, the Totaled Health Risks in Vascular Events (THRIVE) score has shown broad utility, allowing prediction of clinical outcome, death, and risk of hemorrhage after tissue-type plasminogen activator (tPA) treatment, irrespective of the type of acute stroke therapy applied to the patient.
Methods—
We used data from the Virtual International Stroke Trials Archive to further validate the THRIVE score in a large cohort of patients receiving tPA or no acute treatment, to confirm the relationship between THRIVE and hemorrhage after tPA, and to compare the THRIVE score with several other available outcome prediction scores.
Results—
The THRIVE score strongly predicts clinical outcome (odds ratio, 0.55 for good outcome [95% CI, 0.53–0.57];
P
<0.001), mortality (odds ratio, 1.57 [95% confidence interval, 1.50–1.64];
P
<0.001), and risk of intracerebral hemorrhage after tPA (odds ratio, 1.34 [95% confidence interval, 1.22–1.46];
P
<0.001). The relationship between THRIVE score and outcome is not influenced by the independent relationship of tPA administration and outcome. In receiver operator characteristic curve analysis, the THRIVE score was superior to several other available outcome prediction scores in the prediction of clinical outcome and mortality.
Conclusions—
The THRIVE score is a simple-to-use tool to predict clinical outcome, mortality, and risk of hemorrhage after thrombolysis in patients with ischemic stroke. Despite its simplicity, the THRIVE score performs better than several other outcome prediction tools. A free Web calculator for the THRIVE score is available at
http://www.thrivescore.org
.
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Affiliation(s)
- Alexander C. Flint
- From the Department of Neuroscience, Kaiser Permanente, Redwood City, CA (A.C.F., B.S.F., S.P.C., V.A.R.); Department of Neurology and Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (H.K.); Departments of Neurology, Neurosurgery, and Radiology, Marcus Stroke and Neuroscience Center, Grady Memorial Hospital, Emory University School of Medicine, Atlanta, GA (R.G.); Department of Neurology, University of California San Francisco (W.S.S.); Stroke Trials Unit, University
| | - Bonnie S. Faigeles
- From the Department of Neuroscience, Kaiser Permanente, Redwood City, CA (A.C.F., B.S.F., S.P.C., V.A.R.); Department of Neurology and Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (H.K.); Departments of Neurology, Neurosurgery, and Radiology, Marcus Stroke and Neuroscience Center, Grady Memorial Hospital, Emory University School of Medicine, Atlanta, GA (R.G.); Department of Neurology, University of California San Francisco (W.S.S.); Stroke Trials Unit, University
| | - Sean P. Cullen
- From the Department of Neuroscience, Kaiser Permanente, Redwood City, CA (A.C.F., B.S.F., S.P.C., V.A.R.); Department of Neurology and Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (H.K.); Departments of Neurology, Neurosurgery, and Radiology, Marcus Stroke and Neuroscience Center, Grady Memorial Hospital, Emory University School of Medicine, Atlanta, GA (R.G.); Department of Neurology, University of California San Francisco (W.S.S.); Stroke Trials Unit, University
| | - Hooman Kamel
- From the Department of Neuroscience, Kaiser Permanente, Redwood City, CA (A.C.F., B.S.F., S.P.C., V.A.R.); Department of Neurology and Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (H.K.); Departments of Neurology, Neurosurgery, and Radiology, Marcus Stroke and Neuroscience Center, Grady Memorial Hospital, Emory University School of Medicine, Atlanta, GA (R.G.); Department of Neurology, University of California San Francisco (W.S.S.); Stroke Trials Unit, University
| | - Vivek A. Rao
- From the Department of Neuroscience, Kaiser Permanente, Redwood City, CA (A.C.F., B.S.F., S.P.C., V.A.R.); Department of Neurology and Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (H.K.); Departments of Neurology, Neurosurgery, and Radiology, Marcus Stroke and Neuroscience Center, Grady Memorial Hospital, Emory University School of Medicine, Atlanta, GA (R.G.); Department of Neurology, University of California San Francisco (W.S.S.); Stroke Trials Unit, University
| | - Rishi Gupta
- From the Department of Neuroscience, Kaiser Permanente, Redwood City, CA (A.C.F., B.S.F., S.P.C., V.A.R.); Department of Neurology and Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (H.K.); Departments of Neurology, Neurosurgery, and Radiology, Marcus Stroke and Neuroscience Center, Grady Memorial Hospital, Emory University School of Medicine, Atlanta, GA (R.G.); Department of Neurology, University of California San Francisco (W.S.S.); Stroke Trials Unit, University
| | - Wade S. Smith
- From the Department of Neuroscience, Kaiser Permanente, Redwood City, CA (A.C.F., B.S.F., S.P.C., V.A.R.); Department of Neurology and Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (H.K.); Departments of Neurology, Neurosurgery, and Radiology, Marcus Stroke and Neuroscience Center, Grady Memorial Hospital, Emory University School of Medicine, Atlanta, GA (R.G.); Department of Neurology, University of California San Francisco (W.S.S.); Stroke Trials Unit, University
| | - Philip M. Bath
- From the Department of Neuroscience, Kaiser Permanente, Redwood City, CA (A.C.F., B.S.F., S.P.C., V.A.R.); Department of Neurology and Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (H.K.); Departments of Neurology, Neurosurgery, and Radiology, Marcus Stroke and Neuroscience Center, Grady Memorial Hospital, Emory University School of Medicine, Atlanta, GA (R.G.); Department of Neurology, University of California San Francisco (W.S.S.); Stroke Trials Unit, University
| | - Geoffrey A. Donnan
- From the Department of Neuroscience, Kaiser Permanente, Redwood City, CA (A.C.F., B.S.F., S.P.C., V.A.R.); Department of Neurology and Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY (H.K.); Departments of Neurology, Neurosurgery, and Radiology, Marcus Stroke and Neuroscience Center, Grady Memorial Hospital, Emory University School of Medicine, Atlanta, GA (R.G.); Department of Neurology, University of California San Francisco (W.S.S.); Stroke Trials Unit, University
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10
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Hajjar K, Fulton RL, Diener HC, Lees KR, Alexandrov A, Bath PMW, Bluhmki E, Claesson L, Curram J, Davis SM, Donnan G, Diener HC, Fisher M, Gregson B, Grotta J, Hacke W, Hennerici MG, Hommel M, Kaste M, Lees KR, Lyden P, Marler J, Muir K, Sacco R, Shuaib A, Teal P, Wahlgren NG, Warach S, Weimar C. Does the cognitive measure Cog-4 show improvement among patients treated with thrombolysis after acute stroke? Int J Stroke 2012; 8:652-6. [PMID: 22813096 DOI: 10.1111/j.1747-4949.2012.00848.x] [Citation(s) in RCA: 6] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Although the established measure of disability post stroke, the modified Rankin Scale emphasizes motor function and may underestimate the importance of cognitive impairment in more disabled patients. A subset of four items from the National Institutes of Health Stroke Scale has been proposed to assess cognitive function after stroke (Cog-4), and to correlate with modified Rankin Scale. Items correspond to orientation, executive function, language, and inattention. We investigated responsiveness of Cog-4 to treatment with thrombolysis and whether it offers information that supplements modified Rankin Scale. METHODS We included 6268 patients from the Virtual International Stroke Trials Archive: 2734 received intravenous thrombolysis and 3534 were treated conservatively. We compared day 90 outcomes between treated and untreated groups, by modified Rankin Scale (illustrative) and by Cog-4 (primary measure) adjusting for age, baseline National Institutes of Health stroke scale, hemispheric lateralisation as well as baseline Cog-4 and baseline National Institutes of Health Stroke Scale excluding baseline Cog-4 separately. Analysis of Cog-4 was repeated within strata of 90 day modified Rankin Scale. Statistical analyses included proportional odds logistic regression and Cochran-Mantel-Haenszel test. RESULTS Modified Rankin Scale showed a difference between treatment groups of expected magnitude (odds ratio 1·56; 95% confidence interval 1·43-1·72; P < 0·001). After adjustment for imbalance in baseline prognostic factors, the distribution of Cog-4 scores at 90 days was better in thrombolysed patients compared with nonthrombolysed patients (odds ratio 1·31; 95% confidence interval 1·18-1·47; P = 0·006). However, Cog-4 analysis stratified by 90-day modified Rankin Scale was neutral between treatment groups (OR 1·01; 95% CI 0·90-1·14), and Cog-4 was not responsive to treatment group even within modified Rankin Scale categories 4 and 5 despite substantial cognitive deficits in these patients. CONCLUSION Although Cog-4 may be responsive to treatment effects, it does not provide additional information beyond modified Rankin Scale assessment.
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Affiliation(s)
- Karim Hajjar
- Department of Neurology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
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11
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O’Donnell M, Xavier D, Diener C, Sacco R, Lisheng L, Zhang H, Pias P, Truelsen T, Chin S, Rangarajan S, DeVilliers L, Damasceno A, Mondo C, Lanas F, Avezum A, Diaz R, Varigos J, Hankey G, Teal P, Kapral M, Ryglewicz D, Czlonkowska A, Skowronska M, Lopez-Jaramillo P, Dans T, Langhorne P, Yusuf S. Rationale and Design of INTERSTROKE: A Global Case-Control Study of Risk Factors for Stroke. Neuroepidemiology 2010; 35:36-44. [DOI: 10.1159/000306058] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Accepted: 01/08/2010] [Indexed: 11/19/2022] Open
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12
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Gunn M, Champion Z, Casey M, Teal P, Casey P. Testicular and spermatozoan parameters in the pukeko (Porphyrio porphyrio melanotus). Anim Reprod Sci 2008; 109:330-42. [DOI: 10.1016/j.anireprosci.2007.11.002] [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: 07/22/2007] [Revised: 11/04/2007] [Accepted: 11/13/2007] [Indexed: 10/22/2022]
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13
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Sinclair SE, Frighetto L, Loewen PS, Sunderji R, Teal P, Fagan SC, Marra CA. Cost-Utility analysis of tissue plasminogen activator therapy for acute ischaemic stroke: a Canadian healthcare perspective. Pharmacoeconomics 2001; 19:927-936. [PMID: 11700779 DOI: 10.2165/00019053-200119090-00004] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
BACKGROUND There are over 40000 ischaemic strokes annually in Canada, which result in significant morbidity, mortality and burden to the healthcare system. A recent, large clinical trial has evaluated tissue plasminogen activator (t-PA) intravenously for the treatment of acute ischaemic stroke with promising outcomes but with an increased risk of symptomatic intracranial haemorrhage. OBJECTIVE To compare clinical and economic outcomes of intravenous t-PA therapy (0.9 mg/kg, to a maximum of 90 mg, initiated within 3 hours of stroke onset) versus no t-PA for acute ischaemic stroke based on the outcomes achieved in the National Institute of Neurological Disorders and Stroke (NINDS) trial. DESIGN A Markov model depicting the natural lifetime course after an initial acute ischaemic stroke. On the basis of this model, a simulated trial compared no t-PA with t-PA. PATIENTS A hypothetical cohort of 1000 patients with acute ischaemic stroke. STUDY PERSPECTIVE Canadian healthcare system. OUTCOME MEASURES Total acute stroke and post-stroke treatment costs and cumulative quality-adjusted life-years (QALYs). RESULTS For a hypothetical cohort of 1000 patients, the estimated lifetime stroke costs were 103100000 Canadian dollars (SCan) [1999 values) in the t-PA arm ($Can103100 per patient) compared with SCan106900000 in the no t-PA arm ($Can106900 per patient), yielding a lifetime cost difference of $Can3800000 in favour of t-PA versus no t-PA (SCan3800 per patient). In the hypothetical cohort, t-PA treatment resulted in 13 130 QALYs versus 9670 QALYs with no t-PA treatment. This translated into a net benefit of 3460 additional QALYs per 1000 patients (3.46 QALYs per patient). No treatment, outcome or economic variables influenced the model outcome. CONCLUSION From the standpoint of cost effectiveness, treatment of acute ischaemic stroke with intravenous t-PA is an economically attractive strategy.
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Affiliation(s)
- S E Sinclair
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, Canada
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14
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Affiliation(s)
- G W Albers
- Stanford Stroke Center, Palo Alto, CA 94304-1705, USA.
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15
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Bede JC, Teal P, Tobe SS. Production of insect juvenile hormone III and its precursors in cell suspension cultures of the sedge, Cyperus iria L. Plant Cell Rep 1999; 19:20-25. [PMID: 30754753 DOI: 10.1007/s002990050704] [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] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Juvenile hormones (JHs) are sesquiterpenoids that regulate metamorphosis and reproduction in most insect species. There has been one report of an insect JH in plants: JH III, methyl-10R,11-epoxy-3,7,11-trimethyl 2E, 6E-dodecadienoate, has been identified in two sedge species, Cyperus iria L. and C. aromaticus (Ridley) Mattf and Kük. This is the first report of callus and cell suspension cultures derived from C. iria. Farnesol and methyl farnesoate, two biosynthetic intermediates of JH III in insects, as well as JH III have been identified in suspension culture cell extracts by gas chromatography-mass spectroscopy. These cultures thus provide a useful in vitro model to investigate the biosynthesis of JH III in the sedge, C. iria.
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Affiliation(s)
- J C Bede
- Department of Zoology, University of Toronto, 25 Harbord St., Toronto, Ontario, M5S 3G5, Canada e-mail: , Fax:+416-9783522, , , , , , CA
| | - P Teal
- CMAVE, United States Department of Agriculture, ARS, Gainesville, FL, P.O. Box 14565, 1700 SW 23 Dr1. Gainesville, FL 32604, USA, , , , , , US
| | - S S Tobe
- Department of Zoology, University of Toronto, 25 Harbord St., Toronto, Ontario, M5S 3G5, Canada e-mail: , Fax:+416-9783522, , , , , , CA
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16
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Affiliation(s)
- G W Albers
- Stanford University Medical Center, Stanford Stroke Center, Palo Alto, CA 94304-1705, USA
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17
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Norris JW, Buchan A, Cote R, Hachinski V, Phillips SJ, Shuaib A, Silver F, Simard D, Teal P. Canadian guidelines for intravenous thrombolytic treatment in acute stroke. A consensus statement of the Canadian Stroke Consortium. Neurol Sci 1998; 25:257-9. [PMID: 9706731 DOI: 10.1017/s0317167100034120] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND The thromobolytic drug, tissue plasminogen activator (tPA) has been approved in the United States for the treatment of acute ischemic stroke amid controversy and concern about the balance of risk and benefit. The Canadian Stroke Consortium (CSC), a national network of neurologists who collaborate on joint projects in stroke medicine, including clinical trials and consensus statements, has developed guidelines for the use of tPA in Canada. METHODS AND RESULTS The CSC Board of Directors wrote a preliminary report based on existing publications, including randomized drug trials and the report of a special committee struck by the Stroke Council of the American Heart Association. This draft was circulated to the CSC membership-at-large for suggestions or amendments, to produce this final draft. CONCLUSIONS The present guidelines have been devised to represent a Canadian viewpoint of management. The Health Protection Branch of the Ministry of Health of Canada has not yet produced an evaluation. Further modification of these guidelines may be necessary when more data from clinical trials and experience with the drug become available.
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Affiliation(s)
- J W Norris
- Sunnybrook Health Science Centre, Toronto, Ontario, Canada
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18
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Affiliation(s)
- A Fónagy
- Plant Protection Institute of Hungarian Academy of Sciences, Budapest, Hungary
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19
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Singh RB, Graeb DA, Fung A, Teal P. Cardiac rupture complicating cerebral intraarterial thrombolytic therapy. AJNR Am J Neuroradiol 1997; 18:1881-3. [PMID: 9403446 PMCID: PMC8337355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We report a case of fatal cardiac rupture occurring during intraarterial thrombolytic therapy for acute embolic stroke in a patient with recent myocardial infarction.
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Affiliation(s)
- R B Singh
- Department of Radiology, Vancouver Hospital and Health Sciences Centre, British Columbia, Canada
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20
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Abstract
PURPOSE To evaluate the results of excimer laser photorefractive keratectomy (PRK) using an erodible mask to treat myopic astigmatism. SETTING Douglas Memorial Hospital Medical Centre, Fore Erie, Ontario, Canada. METHODS Photorefractive keratectomy was done on 25 consecutive eyes of 25 patients with myopic astigmatism using the OmniMed excimer laser and a compound single-use myopic erodible mask manufactured to produce a specific spherical and cylindrical correction for each individual patient. Follow-up ranged from 6 months for 25 patients to 1 year for 5 patients. RESULTS Six months after PRK, the mean preoperative sphere of -7.46 diopters (D) decreased to -0.17 D and the mean preoperative cylinder of 2.31 D dropped to 0.69 D; 73% of astigmatism was corrected. In the five eyes followed for 1 year, 94% of astigmatism was corrected. Correction of the myopic component was less predictable, with a wider than anticipated range of overcorrection. CONCLUSIONS Excimer laser PRK successfully corrected myopic astigmatism in patients with low and high myopia. The less predictable myopia results may have been secondary to increased procedure time, corneal dehydration, and difficulty in patient fixation and thus alignment.
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Affiliation(s)
- C Niles
- Douglas Memorial Hospital Medical Centre, Fort Erie, Ontario, Canada
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21
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Abstract
Corneal subepithelial opacification associated with pain, photophobia, and injection has been reported in the first to third day following photorefractive keratectomy (PRK). Regardless of treatment, the resolution has generally left the patient with permanent corneal scarring and a one to two line reduction in visual acuity. We surveyed 50 PRK surgeons and received responses from 17 on 30 cases of this complication, which occurs in approximately one in 300 cases. The etiology is unknown. Cases were first reported when nonsteroidal anti-inflammatory drugs, with or without occlusive contact lens, were substituted for conventional bandage occlusion in the postoperative protocol for PRK.
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Affiliation(s)
- P Teal
- Eye Laser Centre, Fort Erie, Ontario, Canada
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22
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Sher NA, Krueger RR, Teal P, Jans RG, Edmison D. Role of topical corticosteroids and nonsteroidal antiinflammatory drugs in the etiology of stromal infiltrates after excimer photorefractive keratectomy. J Refract Corneal Surg 1994; 10:587-8. [PMID: 7530111] [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: 01/25/2023]
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Chaves CJ, Caplan LR, Chung CS, Tapia J, Amarenco P, Teal P, Wityk R, Estol C, Tettenborn B, Rosengart A. Cerebellar infarcts in the New England Medical Center Posterior Circulation Stroke Registry. Neurology 1994; 44:1385-90. [PMID: 8058134 DOI: 10.1212/wnl.44.8.1385] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [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: 01/28/2023] Open
Abstract
We report the clinical findings and stroke mechanisms of 63 patients with cerebellar infarcts. We divided the intracranial vertebrobasilar circulation into the proximal territory (P), fed by the intracranial vertebral arteries and their branches; the middle territory (M), fed by the proximal and middle basilar artery and its branches; and the distal territory (D), fed by the rostral basilar artery and its branches. Cerebellar infarcts were classified by vascular territories P, M, D, P&D, and middle-plus (P&M, M&D, and P&M&D). Patients with P infarcts (11 patients) frequently had vertigo, gait instability, limb ataxia, and headache, whereas patients with D infarcts (15 patients) most often had limb ataxia, gait instability, and dysarthria. Patients with P&D infarcts (17 patients) had signs and symptoms of both groups combined. Infarcts in which the middle territory was involved, either alone (three patients) or combined with other territories (17 patients) were dominated by brainstem signs and symptoms. The predominant stroke mechanisms in the P, D, and P&D groups were embolic due to intra-arterial or cardiac embolism. When the M territory was involved, either alone or with P, D, or P&D territories, stroke mechanisms were more varied, and there was often large-artery occlusion with hemodynamic ischemia.
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Affiliation(s)
- C J Chaves
- Department of Neurology, New England Medical Center, Tufts University, Boston, MA 02111
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24
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Lindsey RW, Teal P, Probe RA, Rhoads D, Davenport S, Schauder K. Early experience with the gamma interlocking nail for peritrochanteric fractures of the proximal femur. J Trauma 1991; 31:1649-58. [PMID: 1749038 DOI: 10.1097/00005373-199112000-00015] [Citation(s) in RCA: 65] [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] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Surgical fixation, early weight-bearing, and bony union remain a challenge in the treatment of peritrochanteric femur fractures, especially if the fractures are comminuted or unstable. Preliminary experience with the Gamma locking nail, a short intramedullary nail connected to a sliding compression screw augmented with distal locking screws, is presented. In a consecutive series of 29 patients, all fractures were adequately reduced and immediate weight-bearing was begun regardless of fracture configuration (13/27 fractures classified as unstable). Twenty-seven patients were reviewed at 6 months. At follow-up, all patients continued to be ambulatory and all fractures healed. Major complications included screw migration in the femoral head (two patients), difficulty in securely placing the distal screws (eight patients), and a femoral shaft fracture through the distal locking screws following a fall. The technical problems inherent in the device and its instrumentation are discussed. In this early experience, the Gamma nail appears to allow for early patient ambulation regardless of the fracture configuration with excellent clinical results.
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Affiliation(s)
- R W Lindsey
- Division of Orthopedic Surgery, Baylor College of Medicine, Houston, Texas 77030
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25
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Machida CA, Bunzow JR, Searles RP, Van Tol H, Tester B, Neve KA, Teal P, Nipper V, Civelli O. Molecular cloning and expression of the rat beta 1-adrenergic receptor gene. J Biol Chem 1990; 265:12960-5. [PMID: 1695899] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Using the sequence homology approach for cloning related genes within the G-protein-coupled receptor gene family, we have cloned the gene for the rat beta 1-adrenergic receptor (beta 1-AR). The rat beta 1-adrenergic receptor gene was isolated from a lambda EMBL3 rat genomic DNA library using the hamster beta 2-adrenergic receptor (beta 2-AR) coding sequence as a probe under low stringency hybridization conditions. The rat beta 1-AR gene encodes a protein of 466 amino acids that contains one consensus site for N-linked glycosylation (Asn-15) and three consensus sites for cAMP-dependent protein kinase phosphorylation (Ser-296, Ser-301, and Ser-401). The encoded rat beta 1-AR is 98 and 91% similar at the amino acid level with the human beta 1-AR in the transmembrane domains and in the overall sequence, respectively. Genomic Southern blot and gene dosage analyses indicate that the rat beta 1-AR gene is a single copy gene. The tissue distribution of the rat beta 1-AR mRNA was highest in the pineal gland with other brain regions and peripheral tissues, including the heart, expressing the mRNA at moderate levels. The bacteriophage clone containing the rat beta 1-AR gene with its natural promoter was co-transfected with the selectable marker (pRSVneo) conferring neomycin resistance into beta 1-AR-deficient mouse L cells. Analyses of the selected transfectant demonstrates efficient expression of the beta 1-AR gene and functional receptor. 125I-Labeled iodocyanopindolol bound transfectant membranes with an affinity of KD = 24 pm; the beta 1-AR-selective antagonist ICI 89,406 displaced iodocyanopindolol binding with a Ki approximately 140 times lower than that for the beta 2-AR-selective antagonist ICI 118,551. In addition, in the transfectant cell line, adenylylcyclase was stimulated by beta-adrenergic receptor agonists with the rank order of potency of isoproterenol greater than norepinephrine = epinephrine, consistent with properties expected of the beta 1-AR subtype.
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Affiliation(s)
- C A Machida
- Division of Neuroscience, Oregon Regional Primate Research Center, Beaverton 97006
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26
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Machida CA, Bunzow JR, Searles RP, Van Tol H, Tester B, Neve KA, Teal P, Nipper V, Civelli O. Molecular cloning and expression of the rat beta 1-adrenergic receptor gene. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)38253-5] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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27
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Abstract
Two patients with neuroacanthocytosis are described. One presented with parkinsonism and the other resembled diurnal dystonia of the Segawa type. Both patients responded well to dopaminomimetic therapy. A PET scan with fluorodopa revealed a nigrostriatal deficit in the first patient.
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Affiliation(s)
- R F Peppard
- Department of Medicine, University of British Columbia, Vancouver, Canada
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28
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Wolters EC, Hurwitz TA, Mak E, Teal P, Peppard FR, Remick R, Calne S, Calne DB. Clozapine in the treatment of parkinsonian patients with dopaminomimetic psychosis. Neurology 1990; 40:832-4. [PMID: 1970427 DOI: 10.1212/wnl.40.5.832] [Citation(s) in RCA: 112] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
In a double-blind placebo-controlled study, we evaluated the effects of clozapine (75 to 250 mg/day, mean 170.8) on dopaminomimetic psychosis and parkinsonian disability. Clozapine prevented deterioration of psychosis during the increase of dopaminomimetics in the 3 patients who completed the study. Worsening of parkinsonism occurred in 3 of the 6 patients. In the dosage used, clozapine's usefulness was limited by its propensity to produce sedation, confusion, and increased parkinsonism.
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Affiliation(s)
- E C Wolters
- Department of Medicine, University Hospital, University of British Columbia, Vancouver, Canada
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29
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Abstract
Significant neurotoxicity including seizures, encephalopathy and coma may complicate the use of cyclosporin A (CyA). Two patients are described, receiving CyA, who presented with abnormal behaviour, stupor, focal motor activity and were shown to be in complex partial status epilepticus (CPSE). Abnormalities of behaviour and/or stupor in patients receiving CyA may be a manifestation of CPSE. Patients receiving CyA who develop an encephalopathy should have electroencephalography performed at the time of the abnormal behaviour.
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Affiliation(s)
- R E Appleton
- Department of Paediatrics, University of British Columbia, Vancouver, Canada
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30
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Vandenbark AA, Teal P, Offner H. Activation of an encephalitogenic T lymphocyte line with a cellfree supernatant containing basic protein and I region gene products. J Immunol 1987; 138:452-9. [PMID: 2432125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Activation of antigen-specific T lymphocyte lines requires presentation of the relevant antigen by syngeneic accessory cells (AC) that express Class II MHC gene products. To determine if the T cell activation signal was AC associated or was shed into the medium, supernatants from rat thymic AC populations pulsed with guinea pig basic protein (GP-BP) or PPD were used to stimulate resting BP- or PPD-reactive T cell lines derived from Lewis or BN rats. Cellfree supernatants were found to stimulate the T cell lines in an antigen-specific, strain-restricted manner, reflecting the pattern of stimulation observed with intact AC used. The activity of the cellfree supernatant could be enhanced five to 20 times in the presence of activated T lymphocytes, the optimal production occurring over a 6-hr period. The cellfree T lymphocyte activation signal produced in the presence of activated T cell products contained both an antigen-specific, MHC-restricted component (85%) and an antigen-independent, mitogenic component (15%). Supernatants containing GP-BP but not bovine BP or PPD induced highly significant proliferation of the Lewis rat-derived BP-1 T lymphocyte line, and transfer of these supernatant-activated cells produced clinical signs of experimental autoimmune encephalomyelitis (EAE) and DTH reactions to GP-BP. The GP-BP component was not inhibited by either of two monoclonal antibodies directed at determinants on either side of the epitope(s) recognized by BP-1 cells. However, stimulation was inhibited by an anti-I-A but not an anti-I-E monoclonal antibody, suggesting the involvement of a Class II MHC gene product on the T cell activation signal. The supernatant activity could be separated by ultracentrifugation at 100,000 X G for 4 hr into a microsomal pellet and an ultrasupernatant, and both fractions had greatly reduced activity on resting T cells until they were reconstituted by vigorous mixing. These results suggest that T effector cells can be activated by AC-derived microsomal fragments bearing Class II antigens that associate noncovalently with processed antigen. This cellfree signal is sufficient to activate encephalitogenic T lymphocytes to transfer clinical EAE and DTH reactions without need for a direct T cell-AC interaction.
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31
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Vandenbark AA, Teal P, Offner H. Activation of an encephalitogenic T lymphocyte line with a cellfree supernatant containing basic protein and I region gene products. The Journal of Immunology 1987. [DOI: 10.4049/jimmunol.138.2.452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Activation of antigen-specific T lymphocyte lines requires presentation of the relevant antigen by syngeneic accessory cells (AC) that express Class II MHC gene products. To determine if the T cell activation signal was AC associated or was shed into the medium, supernatants from rat thymic AC populations pulsed with guinea pig basic protein (GP-BP) or PPD were used to stimulate resting BP- or PPD-reactive T cell lines derived from Lewis or BN rats. Cellfree supernatants were found to stimulate the T cell lines in an antigen-specific, strain-restricted manner, reflecting the pattern of stimulation observed with intact AC used. The activity of the cellfree supernatant could be enhanced five to 20 times in the presence of activated T lymphocytes, the optimal production occurring over a 6-hr period. The cellfree T lymphocyte activation signal produced in the presence of activated T cell products contained both an antigen-specific, MHC-restricted component (85%) and an antigen-independent, mitogenic component (15%). Supernatants containing GP-BP but not bovine BP or PPD induced highly significant proliferation of the Lewis rat-derived BP-1 T lymphocyte line, and transfer of these supernatant-activated cells produced clinical signs of experimental autoimmune encephalomyelitis (EAE) and DTH reactions to GP-BP. The GP-BP component was not inhibited by either of two monoclonal antibodies directed at determinants on either side of the epitope(s) recognized by BP-1 cells. However, stimulation was inhibited by an anti-I-A but not an anti-I-E monoclonal antibody, suggesting the involvement of a Class II MHC gene product on the T cell activation signal. The supernatant activity could be separated by ultracentrifugation at 100,000 X G for 4 hr into a microsomal pellet and an ultrasupernatant, and both fractions had greatly reduced activity on resting T cells until they were reconstituted by vigorous mixing. These results suggest that T effector cells can be activated by AC-derived microsomal fragments bearing Class II antigens that associate noncovalently with processed antigen. This cellfree signal is sufficient to activate encephalitogenic T lymphocytes to transfer clinical EAE and DTH reactions without need for a direct T cell-AC interaction.
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32
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Arch S, Linstedt A, Whitney G, Teal P, Smock T. Neuropeptide routing in the bag cells: kinetic differences in the appearance of newly labeled peptides in transport and secretion. J Neurosci 1986; 6:1545-52. [PMID: 2423661 PMCID: PMC6568736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The bag cell neurons of Aplysia synthesize and secrete several peptides. Some of these, in addition to the egg-laying hormone (ELH), are strongly implicated in the various alterations of central neuronal activity that accompany an electrical discharge of the bag cells. Thus, the secreted peptides appear to play a variety of roles in the animal's physiology. We have been interested in the intracellular mechanisms that precede peptide secretion from the bag cells because of the evidence that most, if not all, of these peptides are derived from a common precursor. Our objective has been to determine if presumed products of this precursor are processed coordinately following their synthesis. We have concentrated on two peptides (ELH and the acidic peptide, AP) because they are most easily identified in our analytical systems. On pulse-chase radiolabeling of the cells in vitro, we found that labeled AP appears before labeled ELH in axonal transport. This observation is not easily accounted for by the assumption, taken from studies of other peptide-secreting cells, that a precursor to both peptides is loaded into secretory granules before further processing ensues. Since the initial disproportion in the representation of the peptides in transport is no longer detectable at long chase times (18 and 24 hr), we examined the possibilities that ELH production is delayed relative to that of AP or that AP is degraded more rapidly than ELH. No evidence was found for either process. The disproportion between the newly labeled peptides in transport was evident on analysis of the medium bathing bag cells depolarized after 24 hr of chase.(ABSTRACT TRUNCATED AT 250 WORDS)
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33
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Vandenbark AA, Nilaver G, Konat G, Teal P, Offner H. Chronic neurologic dysfunction and demyelination induced in Lewis rats by repeated injections of encephalitogenic T-lymphocyte lines. J Neurosci Res 1986; 16:643-56. [PMID: 2432277 DOI: 10.1002/jnr.490160406] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Experimental autoimmune encephalomyelitis (EAE) in the Lewis rat is characteristically a monophasic paralytic disorder. Recovered rats are thereafter immune to EAE induced by injection of guinea pig basic protein (GP-BP) in complete Freund's adjuvant (CFA), but they are still susceptible to EAE induced by an encephalitogenic T-lymphocyte line (BP-1). Induction of active EAE or injection of a sublethal dose of activated BP-1 cells resulted in a monophasic episode of EAE, followed by recovery of normal neurologic function. Repeated challenges with activated BP-1 cells, however, induced unremitting neurologic signs marked by loss of tail tonicity and incontinence, which persisted for more than 6 months. Histologically, the spinal cord of affected rats revealed attenuation of MBP staining (demyelination) and moderate-to-extensive gliosis associated with increased size of intervening spaces. Inflammatory cell lesions, however, were notably absent. Biophysical analysis of isolated spinal cord myelin from affected rats demonstrated a distorted distribution in subfraction densities and the appearance of extra-myelin proteins in the light myelin subfraction. Immunologically, chronically affected animals were unresponsive to the encephalitogenic determinant on GP-BP, although other BP determinants elicited strong delayed type hypersensitivity (DTH) reactions in rats immunized initially with GP-BP in CFA. These data show that ongoing neurologic dysfunction can be induced in the Lewis rat by a GP-BP specific T-lymphocyte line; they suggest that unremitting clinical signs can persist in the absence both of inflammatory lesions in the CNS and of pronounced immunologic responsiveness to the encephalitogenic determinant of GP-BP.
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