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Zimmer C, Taff CC, Ardia DR, Rosvall KA, Kallenberg C, Bentz AB, Taylor AR, Johnson LS, Vitousek MN. Gene expression in the female tree swallow brain is associated with inter- and intra-population variation in glucocorticoid levels. Horm Behav 2023; 147:105280. [PMID: 36403365 DOI: 10.1016/j.yhbeh.2022.105280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 10/12/2022] [Accepted: 11/07/2022] [Indexed: 11/18/2022]
Abstract
Studies of the evolutionary causes and consequences of variation in circulating glucocorticoids (GCs) have begun to reveal how they are shaped by selection. Yet the extent to which variation in circulating hormones reflects variation in other important regulators of the hypothalamic-pituitary-adrenal (HPA) axis, and whether these relationships vary among populations inhabiting different environments, remain poorly studied. Here, we compare gene expression in the brain of female tree swallows (Tachycineta bicolor) from populations that breed in environments that differ in their unpredictability. We find evidence of inter-population variation in the expression of glucocorticoid and mineralocorticoid receptors in the hypothalamus, with the highest gene expression in a population from an extreme environment, and lower expression in a population from a more consistent environment as well as in birds breeding at an environmentally variable high-altitude site that are part of a population that inhabits a mixture of high and low altitude habitats. Within some populations, variation in circulating GCs predicted differences in gene expression, particularly in the hypothalamus. However, some patterns were present in all populations, whereas others were not. These results are consistent with the idea that some combination of local adaptation and phenotypic plasticity may modify components of the HPA axis affecting stress resilience. Our results also underscore that a comprehensive understanding of the function and evolution of the stress response cannot be gained from measuring circulating hormones alone, and that future studies that apply a more explicitly evolutionary approach to important regulatory traits are likely to provide significant insights.
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Affiliation(s)
- Cedric Zimmer
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA; Laboratoire d'Ethologie Expérimentale et Comparée, LEEC, Université Sorbonne Paris Nord, UR 4443, 93430 Villetaneuse, France.
| | - Conor C Taff
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA; Cornell Lab of Ornithology, Ithaca, NY 14850, USA
| | - Daniel R Ardia
- Department of Biology, Franklin and Marshall College, Lancaster, PA 17604, USA
| | - Kimberly A Rosvall
- Department of Biology, Indiana University Bloomington, Bloomington, IN 47405, USA
| | - Christine Kallenberg
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA
| | - Alexandra B Bentz
- Department of Biology, Indiana University Bloomington, Bloomington, IN 47405, USA; Department of Biology, University of Oklahoma, Norman, OK 73019, USA
| | - Audrey R Taylor
- Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA
| | - L Scott Johnson
- Department of Biological Sciences, Towson University, Towson, MD 21252, USA
| | - Maren N Vitousek
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA; Cornell Lab of Ornithology, Ithaca, NY 14850, USA
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2
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McDuffie LA, Christie KS, Taylor AR, Nol E, Friis C, Harwood CM, Rausch J, Laliberte B, Gesmundo C, Wright JR, Johnson JA. Flyway‐scale GPS tracking reveals migratory routes and key stopover and non‐breeding locations of lesser yellowlegs. Ecol Evol 2022; 12:e9495. [DOI: 10.1002/ece3.9495] [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] [Received: 05/28/2022] [Revised: 10/23/2022] [Accepted: 10/25/2022] [Indexed: 11/11/2022] Open
Affiliation(s)
| | - Katherine S. Christie
- Alaska Department of Fish and Game, Threatened, Endangered and Diversity Program Anchorage Alaska USA
| | - Audrey R. Taylor
- Department of Biological Sciences University of Alaska Anchorage Anchorage Alaska USA
| | - Erica Nol
- Biology Trent University Peterborough Ontario Canada
| | - Christian Friis
- Environment and Climate Change Canada Canadian Wildlife Service Toronto Ontario Canada
| | | | - Jennie Rausch
- Environment and Climate Change Canada Canadian Wildlife Service Yellowknife Northwest Territories Canada
| | - Benoit Laliberte
- Environment and Climate Change Canada Wildlife Management and Regulatory Affairs Gatineau Quebec Canada
| | - Callie Gesmundo
- U.S. Fish and Wildlife Service Migratory Bird Program Anchorage Alaska USA
| | - James R. Wright
- School of Environment and Natural Resources The Ohio State University Columbus Ohio USA
| | - James A. Johnson
- U.S. Fish and Wildlife Service Migratory Bird Program Anchorage Alaska USA
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3
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Bulla M, Reneerkens J, Weiser EL, Sokolov A, Taylor AR, Sittler B, McCaffery BJ, Ruthrauff DR, Catlin DH, Payer DC, Ward DH, Solovyeva DV, Santos ESA, Rakhimberdiev E, Nol E, Kwon E, Brown GS, Hevia GD, Gates HR, Johnson JA, van Gils JA, Hansen J, Lamarre JF, Rausch J, Conklin JR, Liebezeit J, Bêty J, Lang J, Alves JA, Fernández-Elipe J, Exo KM, Bollache L, Bertellotti M, Giroux MA, van de Pol M, Johnson M, Boldenow ML, Valcu M, Soloviev M, Sokolova N, Senner NR, Lecomte N, Meyer N, Schmidt NM, Gilg O, Smith PA, Machín P, McGuire RL, Cerboncini RAS, Ottvall R, van Bemmelen RSA, Swift RJ, Saalfeld ST, Jamieson SE, Brown S, Piersma T, Albrecht T, D'Amico V, Lanctot RB, Kempenaers B. Comment on "Global pattern of nest predation is disrupted by climate change in shorebirds". Science 2019; 364:364/6445/eaaw8529. [PMID: 31196986 DOI: 10.1126/science.aaw8529] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 05/29/2019] [Indexed: 11/02/2022]
Abstract
Kubelka et al (Reports, 9 November 2018, p. 680) claim that climate change has disrupted patterns of nest predation in shorebirds. They report that predation rates have increased since the 1950s, especially in the Arctic. We describe methodological problems with their analyses and argue that there is no solid statistical support for their claims.
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Affiliation(s)
- Martin Bulla
- Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, 82319 Seewiesen, Germany. .,NIOZ Royal Netherlands Institute for Sea Research, Department of Coastal Systems and Utrecht University, 1790 AB Den Burg, Texel, Netherlands.,Faculty of Environmental Sciences, Czech University of Life Sciences, 16521 Prague, Czech Republic
| | - Jeroen Reneerkens
- NIOZ Royal Netherlands Institute for Sea Research, Department of Coastal Systems and Utrecht University, 1790 AB Den Burg, Texel, Netherlands.,Conservation Ecology Group, Groningen Institute for Evolutionary Life Sciences (GELIFES), University of Groningen, 9700 CC Groningen, Netherlands
| | - Emily L Weiser
- Upper Midwest Environmental Sciences Center, U.S. Geological Survey, La Crosse, WI 54603, USA
| | - Aleksandr Sokolov
- Arctic Research Station, Institute of Plant and Animal Ecology, 629400 Labytnangi, Russia
| | - Audrey R Taylor
- Department of Geography and Environmental Studies, University of Alaska, Anchorage, AK 99508, USA
| | - Benoît Sittler
- Nature Conservation and Landscape Ecology, University of Freiburg, 79106 Freiburg, Germany.,Arctic Ecology Research Group (GREA), F-21440 Francheville, France
| | - Brian J McCaffery
- Yukon Delta National Wildlife Refuge, U.S. Fish and Wildlife Service, Grand View, WI 54839, USA
| | - Dan R Ruthrauff
- Alaska Science Center, U.S. Geological Survey, Anchorage, AK 99508, USA
| | - Daniel H Catlin
- Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA 24061, USA
| | - David C Payer
- Natural Resource Sciences, National Park Service, Anchorage, AK 99501, USA
| | - David H Ward
- Alaska Science Center, U.S. Geological Survey, Anchorage, AK 99508, USA
| | - Diana V Solovyeva
- Institute of Biological Problems of the North, FEB RAS, Magadan 685000, Russia
| | - Eduardo S A Santos
- BECO do Departamento de Zoologia, Rua do Matão, Universidade de São Paulo, 05508-090 São Paulo, Brazil
| | - Eldar Rakhimberdiev
- Conservation Ecology Group, Groningen Institute for Evolutionary Life Sciences (GELIFES), University of Groningen, 9700 CC Groningen, Netherlands.,Department of Vertebrate Zoology, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Erica Nol
- Biology Department, Trent University, Peterborough, ON K9J 7B8, Canada
| | - Eunbi Kwon
- Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA 24061, USA
| | - Glen S Brown
- Wildlife Research and Monitoring, Ministry of Natural Resources and Forestry, Peterborough, ON K9L 1Z8, Canada
| | - Glenda D Hevia
- Grupo de Ecofisiología Aplicada al Manejo y Conservación de Fauna Silvestre, Centro para el Estudio de Sistemas Marinos (CESIMAR)-CCT CONICET-CENPAT, 9120 Puerto Madryn, Argentina
| | - H River Gates
- Pacific Flyway Program, National Audubon Society, Anchorage, AK 99501, USA
| | - James A Johnson
- Migratory Bird Management, U.S. Fish and Wildlife Service, Anchorage, AK 99503, USA
| | - Jan A van Gils
- NIOZ Royal Netherlands Institute for Sea Research, Department of Coastal Systems and Utrecht University, 1790 AB Den Burg, Texel, Netherlands
| | - Jannik Hansen
- Department of Bioscience, Aarhus University, 4000 Roskilde, Denmark
| | - Jean-François Lamarre
- Science & Technology Program, Polar Knowledge Canada, Cambridge Bay, NU X0B 0C0, Canada
| | - Jennie Rausch
- Canadian Wildlife Service, Environment and Climate Change Canada, P.O. Box 2310, Yellowknife, NT X1A 2P7, Canada
| | - Jesse R Conklin
- Conservation Ecology Group, Groningen Institute for Evolutionary Life Sciences (GELIFES), University of Groningen, 9700 CC Groningen, Netherlands
| | - Joe Liebezeit
- Audubon Society of Portland, Portland, OR 97210, USA
| | - Joël Bêty
- Department of Biology and Center for Northern Studies, University of Quebec, Rimouski, QC G5L 3A1, Canada
| | - Johannes Lang
- Arctic Ecology Research Group (GREA), F-21440 Francheville, France.,Clinic for Birds, Reptiles, Amphibians and Fish/Working Group for Wildlife Biology, Giessen University, 35392 Giessen, Germany
| | - José A Alves
- DBIO & CESAM-Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal.,South Iceland Research Centre, University of Iceland, Fjolheimar IS-800 Selfoss & IS-861 Gunnarsholt, Iceland
| | | | - Klaus-Michael Exo
- Institute of Avian Research "Vogelwarte Helgoland," 26386 Wilhelmshaven, Germany
| | - Loïc Bollache
- Laboratoire Chrono-environnement, Université de Franche-Comté, UMR 6249 CNRS-UFC, F-25000 Besançon, France
| | - Marcelo Bertellotti
- Grupo de Ecofisiología Aplicada al Manejo y Conservación de Fauna Silvestre, Centro para el Estudio de Sistemas Marinos (CESIMAR)-CCT CONICET-CENPAT, 9120 Puerto Madryn, Argentina
| | | | - Martijn van de Pol
- Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), 6708PB Wageningen, Netherlands
| | - Matthew Johnson
- Plumas National Forest, USDA Forest Service, Quincy, CA 95971, USA
| | - Megan L Boldenow
- Biology and Wildlife Department, University of Alaska, Fairbanks, AK 99775, USA
| | - Mihai Valcu
- Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, 82319 Seewiesen, Germany
| | - Mikhail Soloviev
- Department of Vertebrate Zoology, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Natalya Sokolova
- Arctic Research Station, Institute of Plant and Animal Ecology, 629400 Labytnangi, Russia
| | - Nathan R Senner
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Nicolas Lecomte
- Department of Biology, Université de Moncton, Moncton, NB E1A 3E9, Canada
| | - Nicolas Meyer
- Arctic Ecology Research Group (GREA), F-21440 Francheville, France.,Laboratoire Chrono-environnement, Université de Franche-Comté, UMR 6249 CNRS-UFC, F-25000 Besançon, France
| | - Niels Martin Schmidt
- Department of Bioscience, Aarhus University, 4000 Roskilde, Denmark.,Arctic Research Centre, Aarhus University, 8000 Aarhus C, Denmark
| | - Olivier Gilg
- Arctic Ecology Research Group (GREA), F-21440 Francheville, France.,Laboratoire Chrono-environnement, Université de Franche-Comté, UMR 6249 CNRS-UFC, F-25000 Besançon, France
| | - Paul A Smith
- National Wildlife Research Centre, Environment and Climate Change Canada, Ottawa, ON K1S 5B6, Canada
| | | | - Rebecca L McGuire
- Arctic Beringia Program, Wildlife Conservation Society, Fairbanks, AK 99709, USA
| | | | | | | | - Rose J Swift
- Cornell Lab of Ornithology and Department of Natural Resources, Cornell University, Ithaca, NY 14850, USA
| | - Sarah T Saalfeld
- Migratory Bird Management, U.S. Fish and Wildlife Service, Anchorage, AK 99503, USA
| | - Sarah E Jamieson
- Centre for Wildlife Ecology, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - Stephen Brown
- Shorebird Recovery Program, Manomet Inc., P.O. Box 545, Saxtons River, VT 05154, USA
| | - Theunis Piersma
- NIOZ Royal Netherlands Institute for Sea Research, Department of Coastal Systems and Utrecht University, 1790 AB Den Burg, Texel, Netherlands.,Conservation Ecology Group, Groningen Institute for Evolutionary Life Sciences (GELIFES), University of Groningen, 9700 CC Groningen, Netherlands
| | - Tomas Albrecht
- Institute of Vertebrate Biology, Czech Academy of Sciences, 60300 Brno, Czech Republic.,Faculty of Science, Charles University, 128 44 Prague, Czech Republic
| | - Verónica D'Amico
- Grupo de Ecofisiología Aplicada al Manejo y Conservación de Fauna Silvestre, Centro para el Estudio de Sistemas Marinos (CESIMAR)-CCT CONICET-CENPAT, 9120 Puerto Madryn, Argentina
| | - Richard B Lanctot
- Migratory Bird Management, U.S. Fish and Wildlife Service, Anchorage, AK 99503, USA
| | - Bart Kempenaers
- Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, 82319 Seewiesen, Germany.
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Winter RL, Newhard DK, Taylor AR, Johnson JA, Baravik-Munsell ED. Balloon valvuloplasty in a dog with congenital bicuspid aortic valve and supravalvar aortic stenosis (atypical Shone's complex). J Vet Cardiol 2019; 23:88-95. [PMID: 31174733 DOI: 10.1016/j.jvc.2019.02.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [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: 10/17/2018] [Revised: 02/05/2019] [Accepted: 02/22/2019] [Indexed: 12/27/2022]
Abstract
An 8-month-old intact female pug was presented for evaluation and possible balloon valvuloplasty (BV) for severe aortic stenosis. A bicuspid, severely stenotic aortic valve of type 3 morphology with a supravalvar stenosis component was diagnosed, consistent with the diagnosis of atypical Shone's complex. There was severe concentric hypertrophy of the left ventricle, with increased echogenicity of the myocardium nearest to the endocardial border. Mild left atrial enlargement was observed. Selective angiography and transesophageal echocardiography revealed an enlarged and relatively tortuous ascending aorta. The changes to the ascending aorta and the anatomy of the lesion made retrograde access to the left ventricle challenging. Ultimately, BV was successful using a pediatric valvuloplasty balloon catheter and rapid right ventricular pacing, and the pressure gradient across the aortic valve was decreased by more than 50% compared with preoperative measurements. Although valvar aortic stenosis is rare in veterinary medicine, this report highlights the potential challenges and feasibility of BV for this disease.
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Affiliation(s)
- R L Winter
- Department of Veterinary Clinical Sciences, The Ohio State University College of Veterinary Medicine, 601 Vernon L. Tharp St, Columbus, OH, 43210, USA.
| | - D K Newhard
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Auburn University, 1220 Wire Road, Auburn, AL, 36849, USA
| | - A R Taylor
- Department of Neurology, MedVet Medical and Cancer Center for Pets, 300 E. Wilson Bridge Rd, Worthington, OH, 43085, USA
| | - J A Johnson
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Auburn University, 1220 Wire Road, Auburn, AL, 36849, USA
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5
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Affiliation(s)
- Nasim A Rana
- Oxford Regional Rheumatic Diseases Research Centre, Stoke Mandeville Hospital, Aylesbury, Buckinghamshire
| | - A R Taylor
- Oxford Regional Rheumatic Diseases Research Centre, Stoke Mandeville Hospital, Aylesbury, Buckinghamshire
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6
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Mohrhauser DA, Taylor AR, Underwood KR, Pritchard RH, Wertz-Lutz AE, Blair AD. The influence of maternal energy status during midgestation on beef offspring carcass characteristics and meat quality. J Anim Sci 2016; 93:786-93. [PMID: 25548203 DOI: 10.2527/jas.2014-8567] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Research has suggested that maternal undernutrition may cause the development of a thrifty phenotype in the offspring, potentially resulting in greater adiposity and reduced muscle mass. These alterations in adipose and muscle development could have lasting impacts on offspring growth, carcass characteristics, and meat quality. However, limited research exists evaluating the impact of maternal energy status on these economically important traits of the offspring. Therefore, the objective of this study was to determine the influence of maternal energy status during midgestation on offspring carcass characteristics and meat quality. To alter maternal energy status, cows either grazed dormant, winter range (positive energy status [PES]) or were fed in a drylot at 80% of the energy requirements for BW maintenance (negative energy status [NES]) during a mean period of 102 ± 10.9 to 193 ± 10.9 d of gestation. Changes in BCS, BW, LM area (LMA), and 12th rib backfat were measured throughout midgestation. At the end of midgestation, cows in the NES group had a reduction (P ≤ 0.05) in BCS, BW, LMA, and 12th rib backfat when compared with PES dams. Cows and calves were managed similarly after midgestation through weaning and calves were managed and fed a common diet through the receiving, backgrounding, and finishing phases in the feedlot. Calves were harvested after 208 d in the feedlot, carcass characteristics were recorded, and strip loins were recovered for analysis of objective color and Warner-Bratzler shear force (WBSF). Maternal energy status had no influence on offspring HCW, dressing percent, LMA, percent KPH, marbling score, percent intramuscular fat, objective color, or WBSF (P > 0.10). Progeny of NES cows tended to have improvements in 12th rib backfat and USDA yield grade (P < 0.10). Greater ratio of marbling score to 12th rib fat thickness and ratio of percent intramuscular fat to 12th rib fat thickness (P < 0.05) were discovered in progeny from cows experiencing a NES during midgestation. These results suggest that maternal energy status during midgestation may impact fat deposition in intramuscular and subcutaneous fat depots without impacting muscle mass.
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7
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Taylor AR, Young BD, Levine GJ, Eden K, Corapi W, Rossmeisl JH, Levine JM. Clinical Features and Magnetic Resonance Imaging Findings in 7 Dogs with Central Nervous System Aspergillosis. J Vet Intern Med 2015; 29:1556-63. [PMID: 26473515 PMCID: PMC4895661 DOI: 10.1111/jvim.13648] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2015] [Revised: 09/06/2015] [Accepted: 09/17/2015] [Indexed: 01/03/2023] Open
Abstract
Background Systemic aspergillosis is a manifestation of Aspergillus sp. infection that can result in central nervous system (CNS) involvement with marked alterations in CNS function. Information regarding the clinical presentation and magnetic resonance imaging (MRI) findings in cases of aspergillosis with CNS involvement is lacking, resulting in a need for better understanding of this disease. Hypothesis/Objectives The primary objectives were to describe the clinical features and MRI findings in dogs with CNS aspergillosis. The secondary objectives were to describe clinicopathologic findings and case outcome. Animals Seven dogs with CNS aspergillosis. Methods Archived records from 6 institutions were reviewed to identify cases with MRI of CNS aspergillosis confirmed with serum galactomannan enzyme immunoassay (EIA) testing, culture, or supported by histopathology. Signalment, clinical, MRI, clinicopathologic, histopathologic, and microbiologic findings were recorded and evaluated. Results Aspergillosis of the CNS was identified in 7 dogs from 3 institutions. The median age was 3 years and six were German Shepherd dogs. Five dogs had signs of vestibular dysfunction as a component of multifocal neurological abnormalities. The MRI findings ranged from normal to abnormal, including hemorrhagic infarction and mass lesions. Conclusions and Clinical Importance Until now, all reported MRI findings in dogs with CNS aspergillosis have been abnormal. We document that CNS aspergillosis in dogs, particularly German Shepherd dogs, can be suspected based on neurologic signs, whether MRI findings are normal or abnormal. Confirmatory testing with galactomannan EIA, urine, cerebrospinal fluid (CSF) or tissue culture should be performed in cases where aspergillosis is a differential diagnosis.
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Affiliation(s)
- A R Taylor
- Department of Clinical Sciences, Auburn University, Auburn, AL
| | - B D Young
- Diagnostic Imaging, VCA Alameda East Veterinary Hospital, Denver, CO
| | - G J Levine
- Department of Veterinary Pathobiology, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX
| | - K Eden
- Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA
| | - W Corapi
- Department of Veterinary Pathobiology, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX
| | - J H Rossmeisl
- Department of Small Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA
| | - J M Levine
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX
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Lamontagne S, Taylor AR, Herpich D, Hancock GJ. Submarine groundwater discharge from the South Australian Limestone Coast region estimated using radium and salinity. J Environ Radioact 2015; 140:30-41. [PMID: 25461513 DOI: 10.1016/j.jenvrad.2014.10.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2014] [Revised: 10/22/2014] [Accepted: 10/23/2014] [Indexed: 06/04/2023]
Abstract
The Tertiary Limestone Aquifer (TLA) is one of the major regional hydrogeological systems of southern Australia. Submarine groundwater discharge (SGD) of freshwater from the TLA occurs through spring creeks, beach springs and diffusively through beach sands, but the magnitude of the total flux is not known. Here, a range of potential environmental tracers (including temperature, salinity, (222)Rn, (223)Ra, (224)Ra, (226)Ra, (228)Ra, and (4)He) were measured in potential sources of SGD and in seawater along a 45 km transect off the coastline to evaluate SGD from the TLA. Whilst most tracers had a distinct signature in the sources of water to the coastline, salinity and the radium quartet had the most distinct SGD signal in seawater. A one-dimensional advection-dispersion model was used to estimate the terrestrial freshwater component of SGD (Qfw) using salinity and the recirculated seawater component (Qrsw) using radium activity in seawater. Qfw was estimated at 1.2-4.6 m(3) s(-1), similar in magnitude to previously measured spring creek discharge (∼3 m(3) s(-1)) for the area. This suggests that other terrestrial groundwater discharge processes (beach springs and diffuse discharge through beach sands) were no more than 50% of spring creek discharge. The largest component of total SGD was Qrsw, estimated at 500-1000 m(3) s(-1) and possibly greater. The potential for wave, storm, or buoyancy-driven porewater displacement from the seafloor could explain the large recirculation flux for this section of the Southern Ocean Continental Shelf.
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Affiliation(s)
- S Lamontagne
- CSIRO Land and Water and CSIRO Water for a Healthy Country Flagship, Waite Campus, Waite Road, Urrbrae, SA 5064, Australia.
| | - A R Taylor
- CSIRO Land and Water and CSIRO Water for a Healthy Country Flagship, Waite Campus, Waite Road, Urrbrae, SA 5064, Australia.
| | - D Herpich
- South Australian Department of Environment, Water and Natural Resources, 11 Helen Street, Mt Gambier, SA 5290, Australia.
| | - G J Hancock
- CSIRO Land and Water and Water for a Healthy Country Flagship, Black Mountain, ACT 2601, Australia.
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9
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Taylor SB, Taylor AR, Koenig JI. The interaction of disrupted type II neuregulin 1 and chronic adolescent stress on adult anxiety- and fear-related behaviors. Neuroscience 2012; 249:31-42. [PMID: 23022220 DOI: 10.1016/j.neuroscience.2012.09.045] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [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: 07/18/2012] [Revised: 09/15/2012] [Accepted: 09/19/2012] [Indexed: 01/11/2023]
Abstract
The incidence of anxiety, mood, substance abuse disorders and schizophrenia increases during adolescence. Epidemiological evidence confirms that exposure to stress during sensitive periods of development can create vulnerabilities that put genetically predisposed individuals at increased risk for psychiatric disorders. Neuregulin 1 (NRG1) is a frequently identified schizophrenia susceptibility gene that has also been associated with the psychotic features of bipolar disorder. Previously, we established that Type II NRG1 is expressed in the hypothalamic-pituitary-adrenal (HPA) axis neurocircuitry. We also found, using a line of Nrg1 hypomorphic rats (Nrg1(Tn)), that genetic disruption of Type II NRG1 results in altered HPA axis function and environmental reactivity. The present studies used the Nrg1(Tn) rats to test whether Type II NRG1 gene disruption and chronic stress exposure during adolescence interact to alter adult anxiety- and fear-related behaviors. Male and female Nrg1(Tn) and wild-type rats were exposed to chronic variable stress (CVS) during mid-adolescence and then tested for anxiety-like behavior, cued fear conditioning and basal corticosterone secretion in adulthood. The disruption of Type II NRG1 alone significantly impacts rat anxiety-related behavior by reversing normal sex-related differences and impairs the ability to acquire cued fear conditioning. Sex-specific interactions between genotype and adolescent stress also were identified such that CVS-treated wild-type females exhibited a slight reduction in anxiety-like behavior and basal corticosterone, while CVS-treated Nrg1(Tn) females exhibited a significant increase in cued fear extinction. These studies confirm the importance of Type II NRG1 in anxiety and fear behaviors and point to adolescence as a time when stressful experiences can shape adult behavior and HPA axis function.
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Affiliation(s)
- S B Taylor
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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10
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Taylor AR, Gifondorwa DJ, Robinson MB, Strupe JL, Prevette D, Johnson JE, Hempstead BL, Oppenheim RW, Milligan CE. Motoneuron programmed cell death in response to proBDNF. Dev Neurobiol 2012; 72:699-712. [PMID: 21834083 PMCID: PMC3233653 DOI: 10.1002/dneu.20964] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Motoneurons (MN) as well as most neuronal populations undergo a temporally and spatially specific period of programmed cell death (PCD). Several factors have been considered to regulate the survival of MNs during this period, including availability of muscle-derived trophic support and activity. The possibility that target-derived factors may also negatively regulate MN survival has been considered, but not pursued. Neurotrophin precursors, through their interaction with p75(NTR) and sortilin receptors have been shown to induce cell death during development and following injury in the CNS. In this study, we find that muscle cells produce and secrete proBDNF. ProBDNF through its interaction with p75(NTR) and sortilin, promotes a caspase-dependent death of MNs in culture. We also provide data to suggest that proBDNF regulates MN PCD during development in vivo.
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Affiliation(s)
- AR Taylor
- Department of Neurobiology and Anatomy, Wake Forest University School of Medicine Winston-Salem, NC
| | - DJ Gifondorwa
- Department of Neurobiology and Anatomy, Wake Forest University School of Medicine Winston-Salem, NC
| | - MB Robinson
- Department of Neurobiology and Anatomy, Wake Forest University School of Medicine Winston-Salem, NC
| | - JL Strupe
- Department of Neurobiology and Anatomy, Wake Forest University School of Medicine Winston-Salem, NC
| | - D Prevette
- Department of Neurobiology and Anatomy, Wake Forest University School of Medicine Winston-Salem, NC
| | - JE Johnson
- Department of Neurobiology and Anatomy, Wake Forest University School of Medicine Winston-Salem, NC
| | - BL Hempstead
- Department of Medicine Cornell University Medical Center, NY
| | - RW Oppenheim
- Department of Neurobiology and Anatomy, Wake Forest University School of Medicine Winston-Salem, NC
- Interdisciplinary Neuroscience Program, Wake Forest University School of Medicine Winston-Salem, NC
- ALS Center, Wake Forest University School of Medicine Winston-Salem, NC
| | - CE Milligan
- Department of Neurobiology and Anatomy, Wake Forest University School of Medicine Winston-Salem, NC
- Interdisciplinary Neuroscience Program, Wake Forest University School of Medicine Winston-Salem, NC
- ALS Center, Wake Forest University School of Medicine Winston-Salem, NC
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Taylor SB, Taylor AR, Markham JA, Geurts AM, Kanaskie BZ, Koenig JI. Disruption of the neuregulin 1 gene in the rat alters HPA axis activity and behavioral responses to environmental stimuli. Physiol Behav 2011; 104:205-14. [PMID: 21092742 PMCID: PMC3081908 DOI: 10.1016/j.physbeh.2010.11.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [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: 09/20/2010] [Revised: 11/03/2010] [Accepted: 11/10/2010] [Indexed: 10/18/2022]
Abstract
Exposure to stress can result in an increased risk for psychiatric disorders, especially among genetically predisposed individuals. Neuregulin 1 (NRG1) is a susceptibility gene for schizophrenia and is also associated with psychotic bipolar disorder. In the rat, the neurons of the hypothalamic paraventricular nucleus show strong expression of Nrg1 mRNA. In patients with schizophrenia, a single nucleotide polymorphism in the 5' region of NRG1 interacts with psychosocial stress to affect reactivity to expressed emotion. However, there is virtually no information on the role of NRG1 in hypothalamic-pituitary-adrenal axis function, and whether the protein is expressed in the paraventricular nucleus is unknown. The present studies utilize a unique line of Nrg1 hypomorphic rats (Nrg1(Tn)) generated by gene trapping with the Sleeping Beauty transposon. We first established that the Nrg1(Tn) rats displayed reduced expression of both the mRNA and protein corresponding to the Type II NRG1 isoform. After confirming, using wild type animals, that Type II NRG1 is expressed in the neurocircuitry involved in regulating hypothalamic-pituitary-adrenal axis responses to environmental stimuli, the Nrg1(Tn) rats were then used to test the hypothesis that altered expression of Type II NRG1 disrupts stress regulation and reactivity. In support of this hypothesis, Nrg1(Tn) rats have disrupted basal and acute stress recovery corticosterone secretion, differential changes in expression of glucocorticoid receptors in the pituitary, paraventricular nucleus and hippocampus, and a failure to habituate to an open field. Together, these findings point to NRG1 as a potential novel regulator of neuroendocrine responses to stress as well as behavioral reactivity.
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Affiliation(s)
- S B Taylor
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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Bernheim F, Bernheim ML, Taylor AR, Beard D, Sharp DG, Beard JW. A FACTOR IN DOMESTIC RABBIT PAPILLOMA TISSUE HYDROLYZING THE PAPILLOMA VIRUS PROTEIN. Science 2010; 95:230-1. [PMID: 17797118 DOI: 10.1126/science.95.2461.230] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Sharp DG, Taylor AR, McLean IW, Beard D, Beard JW, Feller AE, Dingle JH. ISOLATION AND CHARACTERIZATION OF INFLUENZA VIRUS B (LEE STRAIN). Science 2010; 98:307-8. [PMID: 17776068 DOI: 10.1126/science.98.2544.307] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Thompson SEM, Callow JA, Callow ME, Wheeler GL, Taylor AR, Brownlee C. Membrane recycling and calcium dynamics during settlement and adhesion of zoospores of the green alga Ulva linza. Plant Cell Environ 2007; 30:733-44. [PMID: 17470149 DOI: 10.1111/j.1365-3040.2007.01661.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Recruitment of individuals of the marine alga Ulva linza on to a suitable habitat involves the settlement of motile zoospores on to a substratum during which a preformed adhesive is secreted by vesicular exocytosis. The fluorescent styryl dye FM 1-43 and fluorescent Ca(2+) indicators were used to follow membrane cycling and changes in cytosolic Ca(2+) ([Ca(2+)](cyt)) associated with settlement. When swimming zoospores were exposed continuously to FM 1-43, the plasma membrane was preferentially labelled. During settlement, FM 1-43-labelled plasma membrane was rapidly internalized reflecting high membrane turnover. The internalized membrane was focused into a discrete region indicating targeting of membrane to an endosome-like compartment. Acetoxymethyl (AM)-ester derivatives were found to be unsuitable for monitoring [Ca(2+)](cyt) because the dyes were rapidly sequestered from the cytoplasm into sub-cellular compartments. [Ca(2+)](cyt) was, however, reliably measured using dextran-conjugated calcium indicators delivered into cells using a biolistic technique. Cells loaded with Oregon Green BAPTA-1 dextran (Invitrogen, Paisley, UK) showed diffuse cytosolic loading and reliably responded to imposed changes in [Ca(2+)](cyt). During settlement, zoospores exhibited both localized and diffuse increases in [Ca(2+)](cyt) implying a role for [Ca(2+)](cyt) in exocytosis of the adhesive.
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Affiliation(s)
- S E M Thompson
- School of Biosciences, The University of Birmingham, Birmingham, and Marine Biological Association, The Laboratory, Citadel Hill, Plymouth, UK
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Abstract
Increased incidence of malignancies within aviators is well documented. Commercial female flyers have been found to have a higher risk of developing breast cancer. However, there has not been any report of male breast cancer related to flying either alone or where malignant melanoma and other primary cancers are also associated. We report two male World War II, British Royal Air Force pilots with primary breast carcinoma associated with two other primary cancer sites.
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Affiliation(s)
- D J Gordon
- Department of Plastic and General Surgery, Stoke Mandeville Hospital, Aylesbury, Buckinghamshire, UK.
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Affiliation(s)
- V Adjetey
- Stoke Mandeville Hospital NHS Trust, Mandeville Road, Aylesbury, Buckinghamshire HP21 8AL, UK
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Taylor AR. Adverse events feasibility study: methodology. N Z Med J 2001; 114:387. [PMID: 11589444] [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: 02/21/2023]
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22
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Taylor AR, Assmann SM. Apparent absence of a redox requirement for blue light activation of pump current in broad bean guard cells. Plant Physiol 2001; 125:329-38. [PMID: 11154340 PMCID: PMC61013 DOI: 10.1104/pp.125.1.329] [Citation(s) in RCA: 10] [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] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
In guard cells, membrane hyperpolarization in response to a blue light (BL) stimulus is achieved by the activation of a plasma membrane H(+)-ATPase. Using the patch clamp technique on broad bean (Vicia faba) guard cells we demonstrate that both steady-state- and BL-induced pump currents require ATP and are blocked by vanadate perfused into the guard cell during patch clamp recording. Background-pump current and BL-activated currents are voltage independent over a wide range of membrane potentials. During BL-activated responses significant hyperpolarization is achieved that is sufficient to promote K(+) uptake. BL activation of pump current becomes desensitized by three or four pulses of 30 s x 100 micromol m(-2) s(-1) BL. This desensitization is not a result of pump inhibition as maximal responses to fusicoccin are observed after full BL desensitization. BL treatments prior to whole cell recording show that BL desensitization is not due to washout of a secondary messenger by whole cell perfusion, but appears to be an important feature of the BL-stimulated pump response. We found no evidence for an electrogenic BL-stimulated redox chain in the plasma membrane of guard cells as no steady-state- or BL-activated currents are detected with NADH or NADPH added to the cytosol in the absence of ATP. Steady-state- nor BL-activated currents are affected by the inclusion along with ATP of 1 mM NADH in the pipette under saturating red light or by including NADPH in the pipette under darkness or saturating red light. These data suggest that reduced products of photosynthesis do not significantly modulate plasma membrane pump currents and are unlikely to be critical regulators in BL-stimulation of the plasma membrane H(+)-ATPase in guard cells.
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Affiliation(s)
- A R Taylor
- Marine Biological Association of the United Kingdom, The Laboratory, Citadel Hill, Plymouth PL1 2PB, United Kingdom.
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English J, Taylor AR, Mashchenko SY, Irwin JA, Basu S, Johnstone D. The Galactic Worm GW 123.4-1.5: A Mushroom-shaped H i Cloud. Astrophys J 2000; 533:L25-L28. [PMID: 10727383 DOI: 10.1086/312592] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/1999] [Accepted: 02/28/2000] [Indexed: 05/23/2023]
Abstract
The Dominion Radio Astrophysical Observatory's Synthesis Telescope provides the highest resolution data (1&arcmin; and 0.82 km s-1) to date of an H i worm candidate. Observed as part of the Canadian Galactic Plane Survey, mushroom-shaped GW 123.4-1.5 extends only a few hundred parsecs, contains approximately 105 M middle dot in circle of neutral hydrogen, and appears unrelated to a conventional shell or chimney structure. Our preliminary Zeus two-dimensional models use a single off-plane explosion with a modest ( approximately 1051 ergs) energy input. These generic simulations generate, interior to an expanding outer blast wave, a buoyant cloud whose structure resembles the morphology of the observed feature. Unlike typical model superbubbles, the stem can be narrow because its width is not governed by the pressure behind the blast wave or the disk scale height. Using this type of approach, it should be possible to more accurately model the thin stem and other details of GW 123.4-1.5 in the future.
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Taylor AR, Russ PD, Lee RE, Weingardt JP. Acute afferent loop obstruction diagnosed with computed tomography: case report. Can Assoc Radiol J 1999; 50:251-4. [PMID: 10459312] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
Affiliation(s)
- A R Taylor
- Department of Radiology, University of Colorado Health Sciences Center, Denver 80262, USA
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Kat CC, Darcy CM, O'Donoghue JM, Taylor AR, Regan PJ. The use of the latissimus dorsi musculocutaneous flap for immediate correction of the deformity resulting from breast conservation surgery. Br J Plast Surg 1999; 52:99-103. [PMID: 10434887 DOI: 10.1054/bjps.1997.3035] [Citation(s) in RCA: 39] [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] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Breast conservation surgery is now widely accepted as the treatment of choice in early breast cancer. Randomised controlled trials have shown comparable recurrence and survival rates following breast conservation when compared to mastectomy, with the perceived advantage that it should leave a cosmetically acceptable result without reconstruction. It is our experience that an adequate local excision may result in a poor cosmetic result with distortion of the nipple position, especially in women with small breasts. Between January 1994 and July 1996, we have performed 30 procedures, combining a wide local excision and axillary lymph node clearance for breast cancer with immediate reconstruction of the defect with a latissimus dorsi musculocutaneous flap. All patients had postoperative radiotherapy to the residual breast and, where appropriate, to the axilla. Adjuvant hormonal therapy or chemotherapy was prescribed where indicated. Patient's ages ranged from 36 to 72 years. All tumours were in the lateral, superior or inferior quadrants. The mean combined operating time was 120 min. Two patients required postoperative blood transfusion. Mean hospital stay was 8 days. Histology confirmed tumour clearance in all cases and six patients had axillary lymph node metastases. There were two cases of minor wound infection and six cases of seroma at the donor site. We conclude that breast cancers are ideally treated by a multidisciplinary team and that an immediate latissimus dorsi musculocutaneous flap may correct the deformities often seen after breast conservation surgery.
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Affiliation(s)
- C C Kat
- Department of Plastic and Reconstructive Surgery, Stoke Mandeville Hospital NHS Trust, Aylesbury, UK
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Hirabayashi H, Hirosawa H, Kobayashi H, Murata Y, Edwards PG, Fomalont EB, Fujisawa K, Ichikawa T, Kii T, Lovell JEJ, Moellenbrock GA, Okayasu R, Inoue M, Kawaguchi N, Kameno S, Shibata KM, Asaki Y, Bushimata T, Enome S, Horiuchi S, Miyaji T, Umemoto T, Migenes V, Wajima K, Nakajima J, Morimoto M, Ellis J, Meier DL, Murphy DW, Preston RA, Smith JG, Tingay SJ, Traub DL, Wietfeldt RD, Benson JM, Claussen MJ, Flatters C, Romney JD, Ulvestad JS, D’Addario LR, Langston GI, Minter AH, Carlson BR, Dewdney PE, Jauncey DL, Reynold JE, Taylor AR, McCulloch PM, Cannon WH, Gurvits LI, Mioduszewski AJ, Schilizzi RT, Booth RS. Overview and initial results of the very long baseline interferometry space observatory programme. Science 1998; 281:1825-9. [PMID: 9743489 DOI: 10.1126/science.281.5384.1825] [Citation(s) in RCA: 127] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
High angular resolution images of extragalactic radio sources are being made with the Highly Advanced Laboratory for Communications and Astronomy (HALCA) satellite and ground-based radio telescopes as part of the Very Long Baseline Interferometry (VLBI) Space Observatory Programme (VSOP). VSOP observations at 1.6 and 5 gigahertz of the milli-arc-second-scale structure of radio quasars enable the quasar core size and the corresponding brightness temperature to be determined, and they enable the motions of jet components that are close to the core to be studied. Here, VSOP images of the gamma-ray source 1156+295, the quasar 1548+056, the ultraluminous quasar 0014+813, and the superluminal quasar 0212+735 are presented and discussed.
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Affiliation(s)
- H Hirabayashi
- H. Hirabayashi, H. Hirosawa, H. Kobayashi, Y. Murata, P. G. Edwards, E. B. Fomalont, K. Fujisawa, T. Ichikawa, T. Kii, J. E. J. Lovell, G. A. Moellenbrock, and R. Okayasu are with the Institute of Space and Astronautical Science, Sagamihara, Kanagawa 22
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Abstract
Patch-clamp technology has greatly increased our knowledge of plant membrane transport. However, the success of patch clamping crucially relies on establishing a high resistance (G omega) seal between the membrane and the patch-clamp pipette. This can prove problematic in many plant-cell preparations. It is therefore of great importance to develop protocols for protoplast isolation, maintenance and seal formation that improve seal rate. This study investigated whether the pH and the K+ and the Cl(-)concentration of the pipette solution had an effect on the seal formation. High pH and absence of K+ significantly promoted membrane sealing, whereas the concentration of Cl- had no effect. To reap the benefit of seal-promoting pipette solutions and yet retain the option to adjust this solution to experimental requirements, a pipette perfusion apparatus was implemented. The perfusion system was successfully applied in cell-attached patch, excised-patch and whole-cell configurations, using plasma membrane and tonoplast of three different species. The system enables complete solution exchange within minutes and is potentially of great benefit in the study of channel selectivity, the application of (cytoplasmic) channel blockers and the study of primary and secondary transport.
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Stuart NS, Warwick J, Blackledge GR, Spooner D, Keen C, Taylor AR, Tyrell C, Webster DJ, Earl H. A randomised phase III cross-over study of tamoxifen versus megestrol acetate in advanced and recurrent breast cancer. Eur J Cancer 1996; 32A:1888-92. [PMID: 8943670 DOI: 10.1016/0959-8049(96)00191-8] [Citation(s) in RCA: 27] [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: 02/03/2023]
Abstract
139 peri- and postmenopausal women with advanced or recurrent breast cancer who had not received prior hormonal therapy were randomised in an open, cross-over study comparing the synthetic progestogen megestrol acetate with tamoxifen. The response rate (CR/PR) to megestrol acetate (25%; 95% confidence interval (CI) 15-35%) was not significantly different from that produced by tamoxifen (33%, CI 22-44%). Time-to-treatment failure was also similar in the two groups. Cross-over treatment was given on progression in 76 cases. Cross-over response (CR/PR) was seen in 3 of 35 patients (9%) receiving megestrol acetate as second-line therapy and in 6 of 41 patients (15%) receiving tamoxifen second-line. There was no significant difference in survival between the groups (P = 0.17) with median survival times of 24 and 32 months for the megestrol acetate and tamoxifen groups, respectively. The toxicity profile of the two drugs was different, although significant toxicity was rare with either agent. Megestrol acetate is an effective treatment for advanced breast cancer in older women when used either as first- or second-line treatment. Cross-over response is seen following both treatments. Given that most patients now receive tamoxifen as adjuvant treatment, megestrol acetate would appear to be one of the logical choices for patients who find the side-effects of tamoxifen unacceptable and for those who relapse on tamoxifen with further hormone therapy being clinically indicated.
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Affiliation(s)
- N S Stuart
- CRC Trials Unit, Queen Elizabeth Medical Centre, Birmingham, U.K
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Abstract
Galaxies are surrounded by large haloes of hot gas which must be replenished as the gas cools. This has led to the concept of galactic 'chimneys'--cavities in the interstellar medium, created by multiple supernova explosions, that can act as conduits for the efficient transport of hot gas from a galaxy's disk to its halo. Here we present a high-resolution map of atomic hydrogen in the Perseus arm of our galaxy, which shows clear evidence for the existence of such a chimney. This chimney appears to have been formed by the energetic winds from a cluster of young massive stars, and may currently have reached the stage of bowing out into the halo.
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Affiliation(s)
- M Normandeau
- Department of Physics and Astronomy, University of Calgary, Alberta, Canada
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Abstract
1. The objective was to use modern mass spectrometric techniques to update current information on the metabolism of trimetazidine in human subjects found by previous studies. 2. Urine and plasma samples were taken from four healthy human volunteers taking part in a larger kinetic study. Each subject received an oral dose of 80-mg trimetazidine daily for 4 days. 3. Identification and quantitation of trimetazidine and its metabolites in urine and plasma were achieved using modern liquid chromatography-mass spectrometric methods. 4. The major drug-related component observed in urine and plasma was unchanged trimetazidine. In addition to the parent drug, 10 metabolites were detected in urine in concentrations ranging from 0.008 (0.01% dose) to 1.094 micrograms.ml-1 (1.4% dose). Metabolic profiles following acute and chronic doses of trimetazidine were qualitatively similar.
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Affiliation(s)
- P J Jackson
- Servier Research and Development, Ltd, Slough, UK
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Abstract
Plasma membranes of guard cells in epidermal peels of Vicia faba and Commelina communis can be made accessible to a patch-clamp pipet by removing a small portion (1-3 micrometers in diameter) of the guard cell wall using a microbeam of ultraviolet light generated by a nitrogen laser. Using this laser microsurgical technique, we have measured channel activity across plasma membranes of V. faba guard cells in both cell-attached and isolated patch configurations. Measurements made in the inside-out patch configuration revealed two distinct K(+)-selective channels. Major advantages of the laser microsurgical technique include the avoidance of enzymatic protoplast isolation, the ability to study cell types that have been difficult to isolate as protoplasts or for which enzymatic isolation protocols result in protoplasts not amenable to patch-clamp studies, the maintenance of positional information in single-channel measurements, reduced disruption of cell-wall-mediated signaling pathways, and the ability to investigate intercellular signaling through studies of cells remaining situated within tissue.
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Affiliation(s)
- G H Henriksen
- Department of Biology, The Pennsylvania State University, University Park 16802, USA
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Taylor AR, Brownsill RD, Grandon H, Lefoulon F, Petit A, Luijten W, Kopelman PG, Walther B. Synthesis of putative metabolites and investigation of the metabolic fate of gliclazide, [1-(3-azabicyclo(3,3,0)oct-3-yl)-3-(4-methylphenylsulfonyl) urea], in diabetic patients. Drug Metab Dispos 1996; 24:55-64. [PMID: 8825191] [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: 02/02/2023] Open
Abstract
Synthesis of postulated hydroxylated metabolites of gliclazide is described together with their detailed structural analysis using 1H-NMR, two-dimensional 1H-NMR, and MS to characterize the products. Metabolism of gliclazide has been investigated in the urine of nine patients of different ethnic origins receiving gliclazide therapy for the treatment of diabetes. Urine extracts were analyzed by GC/MS to quantify and identify the metabolites excreted in urine and the metabolites compared with the synthesized products. Metabolic profiles in all diabetic patients were very similar and comparable with those reported for healthy human volunteers. In addition to the expected metabolites arising from oxidation of the 4-methylphenyl ring, four isomeric hydroxylated products of the azabicyclooctyl ring were identified and the structure of a fifth isomer postulated.
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Affiliation(s)
- A R Taylor
- Servier Research and Development Ltd., Fulmer, Slough, UK
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Hayle AJ, Darling DL, Taylor AR, Tarin D. Transfection of metastatic capability with total genomic DNA from human and mouse metastatic tumour cell lines. Differentiation 1993; 54:177-89. [PMID: 8270145 DOI: 10.1111/j.1432-0436.1993.tb01600.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
From a large series of experiments involving transfer of high molecular weight total genomic DNA from highly metastatic human and mouse tumour cell lines to other mouse tumour cell lines we have derived a few cell lines with greatly augmented metastatic properties. In one of these experiments the transfected cell line (designated AH8 Test) not only colonised the lungs but also formed secondary tumour colonies in several extrapulmonary sites including the skin, skeletal muscles, bone, liver diaphragm, spleen and heart. There were no qualitative and quantitative effects of this magnitude when we used DNA from several non-metastatic or non-tumourigenic sources. Secondary transfection of metastatic capability with DNA obtained from a metastasis formed by one of the primary transfectant lines (AH8 Test) has also been accomplished. Concomitant transfer of human DNA through both transfection cycles in this experiment was confirmed by a variety of methods including Southern blot analysis, in situ hybridisation and polymerase chain reaction (PCR) amplification of DNA using primers recognising human-specific Alu repeat sequences. The findings offer opportunities for the isolation of sequences programming metastatic behaviour and we have cloned and sequenced a fragment of human DNA, which has not been previously characterised, from the transfected cells.
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Affiliation(s)
- A J Hayle
- Nuffield Department of Pathology, John Radcliffe Hospital, University of Oxford, Headington, UK
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Marchant NC, Breen MA, Wallace D, Bass S, Taylor AR, Ings RM, Campbell DB, Williams J. Comparative biodisposition and metabolism of 14C-(+/-)-fenfluramine in mouse, rat, dog and man. Xenobiotica 1992; 22:1251-66. [PMID: 1492418 DOI: 10.3109/00498259209053154] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
1. The comparative metabolism of fenfluramine was investigated in mouse, rat, dog and man following a single oral dose of 14C-(+/-)-fenfluramine hydrochloride (1 mg/kg), and also in rat after eight consecutive 12-h subcutaneous doses (24 mg/kg). 2. Main route of excretion of radioactivity in all species and at all doses was into urine (> 80%), with only minor amounts of radioactivity found in faeces. 3. From all species examined a total of 11 metabolites were observed in urine and plasma by t.l.c. and h.p.l.c. analysis and no metabolite was present in the plasma which was not present in urine. 4. All species dealkylate fenfluramine to the active metabolite norfenfluramine, to a relative greater or lesser extent, with plasma metabolic ratios (norfenfluramine/fenfluramine) showing inter-animal variation (rat >> dog >> mouse = man). 5. These differences are due to the efficient deamination of both compounds to polar inactive metabolites in man, with less dealkylation and lower plasma levels of norfenfluramine compared with the other species studied. 6. In conclusion, major species differences in the metabolism of (+/-)-fenfluramine, both qualitative and quantitative were observed, and no one species had a similar metabolic profile to that found in man.
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Affiliation(s)
- N C Marchant
- Servier Research and Development Ltd., Fulmer, Slough, UK
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Taylor AR, Brownlee C. Localized Patch Clamping of Plasma Membrane of a Polarized Plant Cell : Laser Microsurgery of the Fucus spiralis Rhizoid Cell Wall. Plant Physiol 1992; 99:1686-8. [PMID: 16669092 PMCID: PMC1080682 DOI: 10.1104/pp.99.4.1686] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
We used an ultraviolet laser to rupture a small region of cell wall of a polarized Fucus spiralis rhizoid cell and gained localized access to the plasma membrane at the growing apex. Careful control of cell turgor enabled a small portion of plasma membrane-bound cytoplasm to be exposed. Gigaohm seals allowing single-channel recordings were obtained with a high success rate using this method with conventional patch clamp techniques.
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Affiliation(s)
- A R Taylor
- Marine Biological Association, Plymouth, United Kingdom PL1 2PB
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Abstract
This laboratory has recently reported the occurrence of DNA nicking at the onset of terminal skeletal myogenesis by using the technique of in situ nick translation (Dawson and Lough: Dev. Biol., 127:362-367, 1988). Because 1-beta-D-arabinofuranosylcytosine (araC), a cytocidal agent that is routinely used to removed dividing fibroblasts from myogenic cultures, inhibits DNA repair, it was of interest to determine whether araC treatment resulted in an accumulation of the endogenously created nicks. Thus, we have assessed the accumulation of DNA nicks in myotube cells during a 20 hour araC treatment period at the onset of terminal myogenesis (44-64 hours in vitro) by using three techniques: alkaline sucrose gradient density centrifugation, kinetic in situ nick translation, and cellular in situ nick translation. Although alkaline sucrose gradient centrifugation revealed no detectable nicking after 20 hours, kinetic in situ nick translation analysis revealed subtle but significant increases in DNA nicks caused by araC within 7 hours of drug application, and a 1.5-fold increase in DNA repair sites after 20 hours of drug treatment. That these observations reflected nicking specifically in myotube nuclei was determined by immunocytochemical localization of nicked sites after repair with a biotinylated nucleotide analog (biotin-11-dUTP). The effects of araC were only incompletely reversible, whether or not the drug was removed from the cultures, within 2 days of the treatment period.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- T M Masuck
- Department of Anatomy and Cellular Biology, Medical College of Wisconsin, Milwaukee 53226
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Abstract
An immunohistochemical study was performed on the paraffin sections of 25 tumors in the central nervous system (CNS) with prominent papillary configurations. These tumors included seven metastatic papillary carcinomas, six choroid plexus tumors, four papillary ependymomas, two myxopapillary ependymomas, two papillary pituitary adenomas, two astroblastomas, one papillary meningioma, and one anaplastic astrocytoma with significant papillary changes. The panel of antibodies applied included anti-glial fibrillary acidic protein (GFAP), anti-carcinoembryonic antigen (CEA), anti-vimentin (VM), anti-S-100 protein (S-100 P), anti-cytokeratin, and anti-prealbumin antisera. All ependymomas and astroblastomas examined expressed both VM and GFAP, which were either absent or focally expressed in choroid plexus tumors. In contrast, all choroid plexus tumors showed anti-cytokeratin immunoreactivity that was absent in the ependymomas and astroblastomas. Five choroid plexus tumors also expressed S-100 P, thus differentiating them from metastatic carcinoma that showed negative immunostaining. Anti-CEA antisera immunoreactivity was seen in six metastatic tumors, whereas none of the primary CNS tumors expressed CEA. Prealbumin was expressed in four choroid plexus tumors and two metastatic tumors. Immunohistochemical typing using a panel of antibodies has allowed the differentiation of most of the papillary tumors in the CNS examined in this study.
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Affiliation(s)
- L C Ang
- Department of Pathology, University Hospital, London, Ontario, Canada
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39
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Abstract
An immunohistochemical study was performed on the paraffin sections of 25 tumors in the central nervous system (CNS) with prominent papillary configurations. These tumors included seven metastatic papillary carcinomas, six choroid plexus tumors, four papillary ependymomas, two myxopapillary ependymomas, two papillary pituitary adenomas, two astroblastomas, one papillary meningioma, and one anaplastic astrocytoma with significant papillary changes. The panel of antibodies applied included anti-glial fibrillary acidic protein (GFAP), anti-carcinoembryonic antigen (CEA), anti-vimentin (VM), anti-S-100 protein (S-100 P), anti-cytokeratin, and anti-prealbumin antisera. All ependymomas and astroblastomas examined expressed both VM and GFAP, which were either absent or focally expressed in choroid plexus tumors. In contrast, all choroid plexus tumors showed anti-cytokeratin immunoreactivity that was absent in the ependymomas and astroblastomas. Five choroid plexus tumors also expressed S-100 P, thus differentiating them from metastatic carcinoma that showed negative immunostaining. Anti-CEA antisera immunoreactivity was seen in six metastatic tumors, whereas none of the primary CNS tumors expressed CEA. Prealbumin was expressed in four choroid plexus tumors and two metastatic tumors. Immunohistochemical typing using a panel of antibodies has allowed the differentiation of most of the papillary tumors in the CNS examined in this study.
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Affiliation(s)
- L C Ang
- Department of Pathology, University Hospital, London, Ontario, Canada
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Ings RM, Gray AJ, Taylor AR, Gordon BH, Breen M, Hiley M, Brownsill R, Marchant N, Richards R, Wallace D. Disposition, pharmacokinetics, and metabolism of 14C-fotemustine in cancer patients. Eur J Cancer 1990; 26:838-42. [PMID: 2145908 DOI: 10.1016/0277-5379(90)90166-q] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The pharmacokinetics and metabolism of intravenously infused 14C-fotemustine (about 100 mg/m2) were examined in 2 cancer patients. Plasma levels of radioactivity increased to a maximum of 4.1 and 5.5 micrograms equivalents per g when the infusion stopped then declined triexponentially with mean half-lives of about 1/2, 10 and 80 h for the initial, mid and terminal phases, respectively. Plasma levels of intact drug were lower, with maximum levels of 1.1 and 2.8 micrograms/ml, and declined monophasically with a half-life of about 24 min. Plasma clearance was high (1426 and 764 ml/min) with the volume of distribution based on areas of 47.7 and 26.4 l. Most of the radioactivity was eliminated in urine (50.1 and 61.3%) over 7 days with smaller amounts in the feces (6.8 and 0.3%) and only minimal quantities (under 0.1%) as expired carbon dioxide. Metabolites of fotemustine were identified as chloroethanol and N-nitroso-1-imidazolone-ethyl-diethylphosphonate in plasma and as 1-hydantoin-ethyl-diethyl-phosphonate and acetic acid in urine.
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Affiliation(s)
- R M Ings
- Servier Research and Development Ltd., Fulmer, Slough, Bucks
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Summers GD, Taylor AR, Webley M. Elbow synovectomy and excision of the radial head in rheumatoid arthritis: a short term palliative procedure. J Rheumatol 1988; 15:566-9. [PMID: 2456388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We present the results of synovectomy and excision of the radial head in 65 elbows affected by rheumatoid arthritis. Eighty-four percent of elbows had good pain relief 6 months after operation but after an average of 5 years only 54% remained relatively pain-free. Range of motion remained the same or improved in the majority of patients. Synovitis occurred in 39% of elbows during the followup period and intraarticular steroid injections were frequently given. This undoubtedly modified results of pain relief that might have been attributed to the operation. Destructive changes in the humeroulnar joint were considered the main cause of elbow pain at the time of review.
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Affiliation(s)
- G D Summers
- Department of Rheumatology, Stoke Mandeville Hospital, Aylesbury, Buckinghamshire, England
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Niemtzow RC, Taylor AR, Reutershan TP, Rebuck HI, Belford WB, Josuweit RA, Haacke RH, Williams KD, Ball TP. Amateur radio communications and the National Disaster Medical System. Mil Med 1987; 152:622-5. [PMID: 3122093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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Abstract
The purpose of the present study was to assess the social adaptation of mainstreamed mildly retarded children, comparing them to a matched sample of regular education students. Results indicated that mildly retarded children were quite rejected by their peers, and, compared to nonretarded classmates, they reported significantly more dissatisfaction and anxiety about their peer relations. With respect to behavioral style, there were no group differences in peer- or teacher-reported aggressiveness or disruptiveness. However, retarded children were perceived as more shy and avoidant, as less cooperative, and as less likely to exhibit leadership skills. Further analysis of the behavioral assessment data, via cluster analysis, revealed 2 subtypes of rejected retarded children: an internalizing group perceived as displaying high levels of shy/avoidant behavior and an externalizing group perceived as high in aggressive and/or disruptive behavior. In addition, the internalizing group reported higher social anxiety than did the externalizing group. Implications for school-based intervention research with mildly retarded children are discussed.
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Affiliation(s)
- A R Taylor
- Department of Human Development, University of Maryland, College Park 20742
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Abstract
A review of the literature reveals that radial-head excision for rheumatoid destruction of the elbow is a worthwhile operation, producing complete pain relief in many and substantial improvement in approximately 75%. Recurrence of symptoms eventually occurs in 50% patients.
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Abstract
Thirty patients were managed with the use of a simple means of external fixation. Ten of these patients had multiple injuries. In 18 the fractures were open. Five cases had loss of bone length and infected wounds when first seen and were treated with the aid of microvascular surgical procedures. Eight cases required skin grafting. One case required a vein graft to the popliteal artery. The method described is simple to use. It requires little previous experience and is cost effective. We recommend its use in the initial treatment of grade 2 and 3 open fractures. It may also be used on closed unstable fractures, and will maintain limb length in severe injuries with loss of bone substance while further treatment is considered or performed.
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Bryant FR, Taylor AR, Lehman IR. Interaction of the recA protein of Escherichia coli with single-stranded DNA. J Biol Chem 1985; 260:1196-202. [PMID: 3838171] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The interaction of recA protein with single-stranded (ss) phi X174 DNA has been examined by means of a nuclease protection assay. The stoichiometry of protection was found to be 1 recA monomer/approximately 4 nucleotides of ssDNA both in the absence of a nucleotide cofactor and in the presence of ATP. In contrast, in the presence of adenosine 5'-O-(thiotriphosphate) (ATP gamma S) the stoichiometry was 1 recA monomer/approximately 8 nucleotides. No protection was seen with ADP. In the absence of a nucleotide cofactor, the binding of recA protein to ssDNA was quite stable as judged by equilibration with a challenge DNA (t1/2 approximately 30 min). Addition of ATP stimulated this transfer (t1/2 approximately 3 min) as did ADP (t1/2 approximately 0.2 min). ATP gamma S greatly reduced the rate of equilibration (t1/2 greater than 12 h). Direct visualization of recA X ssDNA complexes at subsaturating recA protein concentrations using electron microscopy revealed individual ssDNA molecules partially covered with recA protein which were converted to highly condensed networks upon addition of ATP gamma S. These results have led to a general model for the interaction of recA protein with ssDNA.
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Silver RB, Saft MS, Taylor AR, Cole RD. Identification of nonmitochondrial creatine kinase enzymatic activity in isolated sea urchin mitotic apparatus. J Biol Chem 1983; 258:13287-91. [PMID: 6313691] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
ATP-dependent calcium sequestration was previously localized in vesicles of mitotic apparatus isolated from sea urchins. We now demonstrate that the mitotic apparatus contains an ATP-regenerative system characterized as creatine kinase (EC 2.7.3.2). Mitotic apparatus isolated with vesicles intact converted ADP to ATP if phosphocreatine was present. Omission of ADP or phosphocreatine gave negligible ATP. When mitotic apparatus were washed with detergent-containing buffer to remove vesicles, their ability to produce ATP from ADP and phosphocreatine was reduced. Assays of creatine kinase activity using NADP+:glucose-6-phosphate dehydrogenase indicated that 70% of the creatine kinase activity was extractable with 0.5% Triton X-100. The insoluble residue containing the skeleton of the mitotic apparatus had the rest of the activity. Experiments with a luciferin/luciferase assay showed that Triton removed above 82% of the activity. Preparations of intact mitotic apparatus were free of cytochrome c oxidase (EC 1.9.3.1) activity and therefore free of mitochondria. About 10(8) mitotic apparatus (total volume about 1 liter) could produce 17 mmol of ATP/min when substrates were not limiting. The creatine kinase enzyme activity described herein and the previously described membrane vesicular calcium sequestration system are nonmitochondrial, integral constituents of the sea urchin mitotic apparatus.
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Kingston RE, Gutell RR, Taylor AR, Chamberlin MJ. Transcriptional mapping of plasmid pKK3535. Quantitation of the effect of guanosine tetraphosphate on binding to the rrnB promoters and a lambda promoter with sequence homologies in the CII binding region. J Mol Biol 1981; 146:433-49. [PMID: 6168764 DOI: 10.1016/0022-2836(81)90041-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Abstract
A simple and versatile method for external fixation of fractures of long bones is described. The method was first used in 1976 in a successful attempt to save a limb which had sustained a severe comminuted fracture of the tibia with vascular impairment.
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