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Sepp T, Baines C, Kreitsberg R, Scharsack JP, Nogueira P, Lang T, Fort J, Sild E, Clarke JT, Tuvikene A, Meitern R. Differences on the level of hepatic transcriptome between two flatfish species in response to liver cancer and environmental pollution levels. Comp Biochem Physiol C Toxicol Pharmacol 2024; 275:109781. [PMID: 37923151 DOI: 10.1016/j.cbpc.2023.109781] [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: 08/02/2023] [Revised: 09/20/2023] [Accepted: 10/23/2023] [Indexed: 11/07/2023]
Abstract
Environmental factors can cause cancer in both wild animals and humans. In ecological settings, genetic variation and natural selection can sometimes produce resilience to the negative impacts of environmental change. An increase in oncogenic substances in natural habitats has therefore, unintentionally, created opportunities for using polluted habitats to study cancer defence mechanisms. The Baltic and North Sea are among the most contaminated marine areas, with a long history of pollution. Two flatfish species (flounder, Platichthys flesus and dab, Limanda limanda) are used as ecotoxicological indicator species due to pollution-induced liver cancer. Cancer is more prevalent in dab, suggesting species-specific differences in vulnerability and/or defence mechanisms. We conducted gene expression analyses for 30 flatfishes. We characterize between- and within-species patterns in potential cancer-related mechanisms. By comparing cancerous and healthy fishes, and non-cancerous fishes from clean and polluted sites, we suggest also genes and related physiological mechanisms that could contribute to a higher resistance to pollution-induced cancer in flounders. We discovered changes in transcriptome related to elevated pollutant metabolism, alongside greater tumour suppression mechanisms in the liver tissue of flounders compared to dabs. This suggests either hormetic upregulation of tumour suppression or a stronger natural selection pressure for higher cancer resistance for flounders in polluted environment. Based on gene expression patterns seen in cancerous and healthy fish, for liver cancer to develop in flounders, genetic defence mechanisms need to be suppressed, while in dabs, analogous process is weak or absent. We conclude that wild species could offer novel insights and ideas for understanding the nature and evolution of natural cancer defence mechanisms.
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Affiliation(s)
- Tuul Sepp
- Institute of Ecology and Earth Sciences, University of Tartu, Liivi 2, 50409 Tartu, Estonia. https://twitter.com/@TuulSeppLab
| | - Ciara Baines
- Institute of Ecology and Earth Sciences, University of Tartu, Liivi 2, 50409 Tartu, Estonia; Estonian Marine Institute, University of Tartu, Mäealuse 14, 12618 Tallinn, Harju County, Estonia
| | - Randel Kreitsberg
- Institute of Ecology and Earth Sciences, University of Tartu, Liivi 2, 50409 Tartu, Estonia
| | - Jörn Peter Scharsack
- Thünen Institute of Fisheries Ecology, Herwigstraße 31, 27572 Bremerhaven, Germany
| | - Pedro Nogueira
- Thünen Institute of Fisheries Ecology, Herwigstraße 31, 27572 Bremerhaven, Germany
| | - Thomas Lang
- Thünen Institute of Fisheries Ecology, Herwigstraße 31, 27572 Bremerhaven, Germany
| | - Jérôme Fort
- Littoral, Environnement et Sociétés (LIENSs), UMR7266 CNRS - La Rochelle University, 2 rue Olympe de Gouges, 17000 La Rochelle, France
| | - Elin Sild
- Institute of Ecology and Earth Sciences, University of Tartu, Liivi 2, 50409 Tartu, Estonia
| | - John T Clarke
- Institute of Ecology and Earth Sciences, University of Tartu, Liivi 2, 50409 Tartu, Estonia; GeoBio-Center, Ludwig-Maximilians-Universität München, Richard-Wagner-Str. 10, 80333 Munich, Germany; Department of Earth and Environmental Sciences, Paleontology & Geobiology, Ludwig Maximilians-Universität München, Richard-Wagner-Str. 10, 80333 Munich, Germany; Department of Ecology and Biogeography, Nicolaus Copernicus University in Toruń, Lwowska 1, 87-100 Toruń, Poland
| | - Arvo Tuvikene
- Estonian University of Life Sciences, Friedrich Reinhold Kreutzwaldi 1a, 51014 Tartu, Estonia
| | - Richard Meitern
- Institute of Ecology and Earth Sciences, University of Tartu, Liivi 2, 50409 Tartu, Estonia
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Meng Y, Davison J, Clarke JT, Zobel M, Gerz M, Moora M, Öpik M, Bueno CG. Environmental modulation of plant mycorrhizal traits in the global flora. Ecol Lett 2023; 26:1862-1876. [PMID: 37766496 DOI: 10.1111/ele.14309] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 08/15/2023] [Accepted: 08/21/2023] [Indexed: 09/29/2023]
Abstract
Mycorrhizal symbioses are known to strongly influence plant performance, structure plant communities and shape ecosystem dynamics. Plant mycorrhizal traits, such as those characterising mycorrhizal type (arbuscular (AM), ecto-, ericoid or orchid mycorrhiza) and status (obligately (OM), facultatively (FM) or non-mycorrhizal) offer valuable insight into plant belowground functionality. Here, we compile available plant mycorrhizal trait information and global occurrence data (∼ 100 million records) for 11,770 vascular plant species. Using a plant phylogenetic mega-tree and high-resolution climatic and edaphic data layers, we assess phylogenetic and environmental correlates of plant mycorrhizal traits. We find that plant mycorrhizal type is more phylogenetically conserved than plant mycorrhizal status, while environmental variables (both climatic and edaphic; notably soil texture) explain more variation in mycorrhizal status, especially FM. The previously underestimated role of environmental conditions has far-reaching implications for our understanding of ecosystem functioning under changing climatic and soil conditions.
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Affiliation(s)
- Yiming Meng
- Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia
| | - John Davison
- Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia
| | - John T Clarke
- GeoBio-Center, Ludwig-Maximilians-Universität München, Munich, Germany
- Department of Earth and Environmental Sciences, Paleontology & Geobiology, Ludwig-Maximilians-Universität München, Munich, Germany
- Department of Ecology and Biogeography, Nicolaus Copernicus University in Toruń, Toruń, Poland
- Department of Zoology, Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia
| | - Martin Zobel
- Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia
| | - Maret Gerz
- Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia
| | - Mari Moora
- Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia
| | - Maarja Öpik
- Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia
| | - C Guillermo Bueno
- Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia
- Pyrenean Institute of Ecology, IPE-CSIC, Jaca, Spain
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Clarke JT. Evidence for general size-by-habitat rules in actinopterygian fishes across nine scales of observation. Ecol Lett 2021; 24:1569-1581. [PMID: 34110065 PMCID: PMC8362132 DOI: 10.1111/ele.13768] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [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: 02/23/2021] [Accepted: 04/08/2021] [Indexed: 11/30/2022]
Abstract
Identifying environmental predictors of phenotype is fundamentally important to many ecological questions, from revealing broadscale ecological processes to predicting extinction risk. However, establishing robust environment—phenotype relationships is challenging, as powerful case studies require diverse clades which repeatedly undergo environmental transitions at multiple taxonomic scales. Actinopterygian fishes, with 32,000+ species, fulfil these criteria for the fundamental habitat divisions in water. With four datasets of body size (ranging 10,905–27,226 species), I reveal highly consistent size‐by‐habitat‐use patterns across nine scales of observation. Taxa in marine, marine‐brackish, euryhaline and freshwater‐brackish habitats possess larger mean sizes than freshwater relatives, and the largest mean sizes consistently emerge within marine‐brackish and euryhaline taxa. These findings align with the predictions of seven mechanisms thought to drive larger size by promoting additional trophic levels. However, mismatches between size and trophic‐level patterns highlight a role for additional mechanisms, and support for viable candidates is examined in 3439 comparisons.
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Affiliation(s)
- John T Clarke
- Department of Ecology and Biogeography, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University, Toruń, Poland.,Institute of Ecology and Earth Sciences, Department of Zoology, University of Tartu, Tartu, Estonia
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Butler B, Gamble-George J, Prins P, North A, Clarke JT, Khoshbouei H. Chronic Methamphetamine Increases Alpha-Synuclein Protein Levels in the Striatum and Hippocampus but not in the Cortex of Juvenile Mice. J Addict Prev 2015; 2:6. [PMID: 25621291 PMCID: PMC4303106] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Methamphetamine is the second most widely used illicit drug worldwide. More than 290 tons of methamphetamine was synthesized in the year 2005 alone, corresponding to approximately ~3 billion 100 mg doses of methamphetamine. Drug addicts abuse high concentrations of methamphetamine for months and even years. Current reports in the literature are consistent with the interpretation that methamphetamine-induced neuronal injury may render methamphetamine users more susceptible to neurodegenerative pathologies. Specifically, chronic exposure to psychostimulants is associated with increases in striatal alpha-synuclein expression, a synaptic protein implicated in the pathogenesis of neurodegenerative diseases. This raises the question whether methamphetamine exposure affects alpha-synuclein levels in the brain. In this short report, we examined alpha-synuclein protein and mRNA levels in the striatum, hippocampus and cortex of adolescent male mice following a neurotoxic regimen of methamphetamine (24mg/kg/daily/14days). We found that methamphetamine exposure resulted in a decrease in the monomeric form of alpha-synuclein (molecular species <19 kDa), while increasing higher molecular weight alpha-synuclein species (>19 kDa) in the striatum and hippocampus, but not in the cortex. Despite the elevation of high molecular weight alpha-synuclein species (>19 kDa), there was no change in the alpha-synuclein mRNA levels in the striatum, hippocampus and cortex of mice exposed to methamphetamine. The methamphetamine-induced increase in high molecular weight alpha-synuclein protein levels might be one of the causal mechanisms or one of the compensatory consequences of methamphetamine-mediated neurotoxicity.
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Affiliation(s)
- B Butler
- Department of Neuroscience, University of Florida School of Medicine, Gainesville, Fl 32611, USA
| | - J Gamble-George
- Department of Neuroscience, University of Florida School of Medicine, Gainesville, Fl 32611, USA
| | - P Prins
- Department of Neuroscience, University of Florida School of Medicine, Gainesville, Fl 32611, USA
| | - A North
- Department of Neuroscience, University of Florida School of Medicine, Gainesville, Fl 32611, USA
| | - J T Clarke
- Department of Neuroscience, University of Florida School of Medicine, Gainesville, Fl 32611, USA
| | - H Khoshbouei
- Department of Neuroscience, University of Florida School of Medicine, Gainesville, Fl 32611, USA
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Nichols JD, Badman SV, Baines KH, Brown RH, Bunce EJ, Clarke JT, Cowley SWH, Crary FJ, Dougherty MK, Gérard JC, Grocott A, Grodent D, Kurth WS, Melin H, Mitchell DG, Pryor WR, Stallard TS. Dynamic auroral storms on Saturn as observed by the Hubble Space Telescope. Geophys Res Lett 2014; 41:3323-3330. [PMID: 26074636 PMCID: PMC4459195 DOI: 10.1002/2014gl060186] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 04/28/2014] [Indexed: 05/29/2023]
Abstract
We present observations of significant dynamics within two UV auroral storms observed on Saturn using the Hubble Space Telescope in April/May 2013. Specifically, we discuss bursts of auroral emission observed at the poleward boundary of a solar wind-induced auroral storm, propagating at ∼330% rigid corotation from near ∼01 h LT toward ∼08 h LT. We suggest that these are indicative of ongoing, bursty reconnection of lobe flux in the magnetotail, providing strong evidence that Saturn's auroral storms are caused by large-scale flux closure. We also discuss the later evolution of a similar storm and show that the emission maps to the trailing region of an energetic neutral atom enhancement. We thus identify the auroral form with the upward field-aligned continuity currents flowing into the associated partial ring current.
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Affiliation(s)
- J D Nichols
- Department of Physics and Astronomy, University of Leicester Leicester, UK
| | - S V Badman
- Department of Physics and Astronomy, University of Leicester Leicester, UK ; Department of Physics, Lancaster University Lancaster, UK
| | - K H Baines
- Space Science and Engineering Center, University of Wisconsin-Madison Madison, Wisconsin, USA
| | - R H Brown
- Lunar and Planetary Lab, University of Arizona Tucson, Arizona, USA
| | - E J Bunce
- Department of Physics and Astronomy, University of Leicester Leicester, UK
| | - J T Clarke
- Center for Space Physics, Boston University Boston, Massachusetts, USA
| | - S W H Cowley
- Department of Physics and Astronomy, University of Leicester Leicester, UK
| | - F J Crary
- Laboratory for Atmospheric and Space Physics, University of Colorado Boulder Boulder, Colorado, USA
| | - M K Dougherty
- Blackett Laboratory, Imperial College London London, UK
| | - J-C Gérard
- Laboratoire de Physique Atmospherique et Planetaire, Universite de Liege Liege, Belgium
| | - A Grocott
- Department of Physics and Astronomy, University of Leicester Leicester, UK ; Department of Physics, Lancaster University Lancaster, UK
| | - D Grodent
- Laboratoire de Physique Atmospherique et Planetaire, Universite de Liege Liege, Belgium
| | - W S Kurth
- Department of Physics and Astronomy, University of Iowa Iowa City, Iowa, USA
| | - H Melin
- Department of Physics and Astronomy, University of Leicester Leicester, UK
| | - D G Mitchell
- Applied Physics Laboratory, Johns Hopkins University Laurel, Maryland, USA
| | - W R Pryor
- Department of Science, Central Arizona College Coolidge, Arizona, USA
| | - T S Stallard
- Department of Physics and Astronomy, University of Leicester Leicester, UK
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Abstract
• Plants have utterly transformed the planet, but testing hypotheses of causality requires a reliable time-scale for plant evolution. While clock methods have been extensively developed, less attention has been paid to the correct interpretation and appropriate implementation of fossil data. • We constructed 17 calibrations, consisting of minimum constraints and soft maximum constraints, for divergences between model representatives of the major land plant lineages. Using a data set of seven plastid genes, we performed a cross-validation analysis to determine the consistency of the calibrations. Six molecular clock analyses were then conducted, one with the original calibrations, and others exploring the impact on divergence estimates of changing maxima at basal nodes, and prior probability densities within calibrations. • Cross-validation highlighted Tracheophyta and Euphyllophyta calibrations as inconsistent, either because their soft maxima were overly conservative or because of undetected rate variation. Molecular clock analyses yielded estimates ranging from 568-815 million yr before present (Ma) for crown embryophytes and from 175-240 Ma for crown angiosperms. • We reject both a post-Jurassic origin of angiosperms and a post-Cambrian origin of land plants. Our analyses also suggest that the establishment of the major embryophyte lineages occurred at a much slower tempo than suggested in most previous studies. These conclusions are entirely compatible with current palaeobotanical data, although not necessarily with their interpretation by palaeobotanists.
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Affiliation(s)
- John T Clarke
- School of Earth Sciences, University of Bristol, Wills Memorial Building, Queen's Road, Bristol BS8 1RJ, UK
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK
| | - Rachel C M Warnock
- School of Earth Sciences, University of Bristol, Wills Memorial Building, Queen's Road, Bristol BS8 1RJ, UK
| | - Philip C J Donoghue
- School of Earth Sciences, University of Bristol, Wills Memorial Building, Queen's Road, Bristol BS8 1RJ, UK
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Pryor WR, Rymer AM, Mitchell DG, Hill TW, Young DT, Saur J, Jones GH, Jacobsen S, Cowley SWH, Mauk BH, Coates AJ, Gustin J, Grodent D, Gérard JC, Lamy L, Nichols JD, Krimigis SM, Esposito LW, Dougherty MK, Jouchoux AJ, Stewart AIF, McClintock WE, Holsclaw GM, Ajello JM, Colwell JE, Hendrix AR, Crary FJ, Clarke JT, Zhou X. The auroral footprint of Enceladus on Saturn. Nature 2011; 472:331-3. [DOI: 10.1038/nature09928] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Accepted: 02/10/2011] [Indexed: 11/09/2022]
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Jones SA, Almássy Z, Beck M, Burt K, Clarke JT, Giugliani R, Hendriksz C, Kroepfl T, Lavery L, Lin SP, Malm G, Ramaswami U, Tincheva R, Wraith JE. Mortality and cause of death in mucopolysaccharidosis type II-a historical review based on data from the Hunter Outcome Survey (HOS). J Inherit Metab Dis 2009; 32:534-43. [PMID: 19597960 DOI: 10.1007/s10545-009-1119-7] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2008] [Revised: 04/14/2009] [Accepted: 05/12/2009] [Indexed: 11/30/2022]
Abstract
Mucopolysaccharidosis type II (MPS II or Hunter syndrome) is a progressive, multisystemic disease caused by a deficiency of iduronate-2-sulfatase. Patients with the severe form of the disease have cognitive impairment and typically die in the second decade of life. Patients with the less severe form do not experience significant cognitive involvement and may survive until the fifth or sixth decade of life. We studied the relationship of both severity of MPS II and the time period in which patients died with age at death in 129 patients for whom data were entered retrospectively into HOS (Hunter Outcome Survey), the only large-scale, multinational observational study of patients with MPS II. Median age at death was significantly lower in patients with cognitive involvement compared with those without cognitive involvement (11.7 versus 14.1 years; p = 0.024). These data indicate that cognitive involvement is indicative of more severe disease and lower life expectancy in patients with MPS II. Median age at death was significantly lower in patients who died in or before 1985 compared with those who died after 1985 (11.3 versus 14.1 years; p alpha 0.001). The difference in age at death between patients dying in or before, relative to after, the selected cut-off date of 1985 may reflect improvements in patient identification, care and management over the past two decades. Data from patients who died after 1985 could serve as a control in analyses of the effects of enzyme replacement therapy with idursulfase on mortality in patients with MPS II.
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Affiliation(s)
- S A Jones
- Willink Unit, Genetic Medicine, Manchester Academic Health Science Centre, Central Manchester University Hospitals, NHS Foundation Trust, St Mary's Hospital, Manchester, UK.
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9
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Affiliation(s)
- Denis Grodent
- Institut d'Astrophysique et de Géophysique, Laboratory for Planetary and Atmospheric Physics; Université de Liège; Liège Belgium
| | - Bertrand Bonfond
- Institut d'Astrophysique et de Géophysique, Laboratory for Planetary and Atmospheric Physics; Université de Liège; Liège Belgium
| | - Aikaterini Radioti
- Institut d'Astrophysique et de Géophysique, Laboratory for Planetary and Atmospheric Physics; Université de Liège; Liège Belgium
| | - Jean-Claude Gérard
- Institut d'Astrophysique et de Géophysique, Laboratory for Planetary and Atmospheric Physics; Université de Liège; Liège Belgium
| | - Xianzhe Jia
- Institute of Geophysics and Planetary Physics; University of California; Los Angeles California USA
| | | | - John T. Clarke
- Center for Space Physics; Boston University; Boston Massachusetts USA
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Grodent D, Bonfond B, Gérard JC, Radioti A, Gustin J, Clarke JT, Nichols J, Connerney JEP. Auroral evidence of a localized magnetic anomaly in Jupiter's northern hemisphere. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2008ja013185] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Denis Grodent
- Laboratory for Planetary and Atmospheric Physics; Université de Liège; Liège Belgium
| | - Bertrand Bonfond
- Laboratory for Planetary and Atmospheric Physics; Université de Liège; Liège Belgium
| | - Jean-Claude Gérard
- Laboratory for Planetary and Atmospheric Physics; Université de Liège; Liège Belgium
| | - Aikaterini Radioti
- Laboratory for Planetary and Atmospheric Physics; Université de Liège; Liège Belgium
| | - Jacques Gustin
- Laboratory for Planetary and Atmospheric Physics; Université de Liège; Liège Belgium
| | - John T. Clarke
- Center for Space Physics; Boston University; Boston Massachusetts USA
| | - Jonathan Nichols
- Center for Space Physics; Boston University; Boston Massachusetts USA
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Gladstone GR, Stern SA, Slater DC, Versteeg M, Davis MW, Retherford KD, Young LA, Steffl AJ, Throop H, Parker JW, Weaver HA, Cheng AF, Orton GS, Clarke JT, Nichols JD. Jupiter's Nightside Airglow and Aurora. Science 2007; 318:229-31. [DOI: 10.1126/science.1147613] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- G. Randall Gladstone
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - S. Alan Stern
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - David C. Slater
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - Maarten Versteeg
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - Michael W. Davis
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - Kurt D. Retherford
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - Leslie A. Young
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - Andrew J. Steffl
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - Henry Throop
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - Joel Wm. Parker
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - Harold A. Weaver
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - Andrew F. Cheng
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - Glenn S. Orton
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - John T. Clarke
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - Jonathan D. Nichols
- Southwest Research Institute, San Antonio, TX 78238, USA
- NASA Headquarters, Washington, DC 20546, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
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Gérard JC, Saglam A, Grodent D, Clarke JT. Morphology of the ultraviolet Io footprint emission and its control by Io's location. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005ja011327] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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13
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Clarke JT, Gérard JC, Grodent D, Wannawichian S, Gustin J, Connerney J, Crary F, Dougherty M, Kurth W, Cowley SWH, Bunce EJ, Hill T, Kim J. Morphological differences between Saturn's ultraviolet aurorae and those of Earth and Jupiter. Nature 2005; 433:717-9. [PMID: 15716945 DOI: 10.1038/nature03331] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2004] [Accepted: 12/22/2004] [Indexed: 11/10/2022]
Abstract
It has often been stated that Saturn's magnetosphere and aurorae are intermediate between those of Earth, where the dominant processes are solar wind driven, and those of Jupiter, where processes are driven by a large source of internal plasma. But this view is based on information about Saturn that is far inferior to what is now available. Here we report ultraviolet images of Saturn, which, when combined with simultaneous Cassini measurements of the solar wind and Saturn kilometric radio emission, demonstrate that its aurorae differ morphologically from those of both Earth and Jupiter. Saturn's auroral emissions vary slowly; some features appear in partial corotation whereas others are fixed to the solar wind direction; the auroral oval shifts quickly in latitude; and the aurora is often not centred on the magnetic pole nor closed on itself. In response to a large increase in solar wind dynamic pressure Saturn's aurora brightened dramatically, the brightest auroral emissions moved to higher latitudes, and the dawn side polar regions were filled with intense emissions. The brightening is reminiscent of terrestrial aurorae, but the other two variations are not. Rather than being intermediate between the Earth and Jupiter, Saturn's auroral emissions behave fundamentally differently from those at the other planets.
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Affiliation(s)
- J T Clarke
- Boston University, 725 Commonwealth Avenue, Boston, Massachusetts 02215, USA.
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14
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Kurth WS, Gurnett DA, Clarke JT, Zarka P, Desch MD, Kaiser ML, Cecconi B, Lecacheux A, Farrell WM, Galopeau P, Gérard JC, Grodent D, Prangé R, Dougherty MK, Crary FJ. An Earth-like correspondence between Saturn's auroral features and radio emission. Nature 2005; 433:722-5. [PMID: 15716947 DOI: 10.1038/nature03334] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2004] [Accepted: 12/04/2004] [Indexed: 11/09/2022]
Abstract
Saturn is a source of intense kilometre-wavelength radio emissions that are believed to be associated with its polar aurorae, and which provide an important remote diagnostic of its magnetospheric activity. Previous observations implied that the radio emission originated in the polar regions, and indicated a strong correlation with solar wind dynamic pressure. The radio source also appeared to be fixed near local noon and at the latitude of the ultraviolet aurora. There have, however, been no observations relating the radio emissions to detailed auroral structures. Here we report measurements of the radio emissions, which, along with high-resolution images of Saturn's ultraviolet auroral emissions, suggest that although there are differences in the global morphology of the aurorae, Saturn's radio emissions exhibit an Earth-like correspondence between bright auroral features and the radio emissions. This demonstrates the universality of the mechanism that results in emissions near the electron cyclotron frequency narrowly beamed at large angles to the magnetic field.
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Affiliation(s)
- W S Kurth
- Department of Physics and Astronomy, The University of Iowa, Iowa City, Iowa 52242, USA.
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15
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Crary FJ, Clarke JT, Dougherty MK, Hanlon PG, Hansen KC, Steinberg JT, Barraclough BL, Coates AJ, Gérard JC, Grodent D, Kurth WS, Mitchell DG, Rymer AM, Young DT. Solar wind dynamic pressure and electric field as the main factors controlling Saturn's aurorae. Nature 2005; 433:720-2. [PMID: 15716946 DOI: 10.1038/nature03333] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2004] [Accepted: 12/27/2004] [Indexed: 11/09/2022]
Abstract
The interaction of the solar wind with Earth's magnetosphere gives rise to the bright polar aurorae and to geomagnetic storms, but the relation between the solar wind and the dynamics of the outer planets' magnetospheres is poorly understood. Jupiter's magnetospheric dynamics and aurorae are dominated by processes internal to the jovian system, whereas Saturn's magnetosphere has generally been considered to have both internal and solar-wind-driven processes. This hypothesis, however, is tentative because of limited simultaneous solar wind and magnetospheric measurements. Here we report solar wind measurements, immediately upstream of Saturn, over a one-month period. When combined with simultaneous ultraviolet imaging we find that, unlike Jupiter, Saturn's aurorae respond strongly to solar wind conditions. But in contrast to Earth, the main controlling factor appears to be solar wind dynamic pressure and electric field, with the orientation of the interplanetary magnetic field playing a much more limited role. Saturn's magnetosphere is, therefore, strongly driven by the solar wind, but the solar wind conditions that drive it differ from those that drive the Earth's magnetosphere.
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Affiliation(s)
- F J Crary
- Southwest Research Institute, Culebra Road, San Antonio, Texas 78288, USA.
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Gérard JC, Bunce EJ, Grodent D, Cowley SWH, Clarke JT, Badman SV. Signature of Saturn's auroral cusp: Simultaneous Hubble Space Telescope FUV observations and upstream solar wind monitoring. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2005ja011094] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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17
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Clarke JT, Rifkin EB, Johnston HL. Condensed Gas Calorimetry. III. Heat Capacity, Heat of Fusion, Heat of Vaporization, Vapor Pressures and Entropy of Diborane between 13 °K. and the Boiling Point (180.32 °K.)1. J Am Chem Soc 2002. [DOI: 10.1021/ja01100a006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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18
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Swain CG, Stockmayer WH, Clarke JT. Effect of Structure on the Rate of Spontaneous Thermal Decomposition of Substituted Benzoyl Peroxides. J Am Chem Soc 2002. [DOI: 10.1021/ja01168a017] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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19
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Kerr EC, Rifkin EB, Johnston HL, Clarke JT. Condensed Gas Calorimetry. II. Heat Capacity of Ortho-deuterium between 13.1 and 23.6°K., Melting and Boiling Points, Heats of Fusion and Vaporization. Vapor Pressures of Liquid Ortho-deuterium1. J Am Chem Soc 2002. [DOI: 10.1021/ja01145a093] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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21
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Johnston HL, Clarke JT, Rifkin EB, Kerr EC. Condensed Gas Calorimetry. I. Heat Capacities, Latent Heats and Entropies of Pure Para-Hydrogen from 12.7 to 20.3°K. Description of the Condensed Gas Calorimeter in Use in the Cryogenic Laboratory of the Ohio State University1,2. J Am Chem Soc 2002. [DOI: 10.1021/ja01165a028] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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22
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Clarke JT, Ajello J, Ballester G, Ben Jaffel L, Connerney J, Gérard JC, Gladstone GR, Grodent D, Pryor W, Trauger J, Waite JH. Ultraviolet emissions from the magnetic footprints of Io, Ganymede and Europa on Jupiter. Nature 2002; 415:997-1000. [PMID: 11875560 DOI: 10.1038/415997a] [Citation(s) in RCA: 177] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Io leaves a magnetic footprint on Jupiter's upper atmosphere that appears as a spot of ultraviolet emission that remains fixed underneath Io as Jupiter rotates. The specific physical mechanisms responsible for generating those emissions are not well understood, but in general the spot seems to arise because of an electromagnetic interaction between Jupiter's magnetic field and the plasma surrounding Io, driving currents of around 1 million amperes down through Jupiter's ionosphere. The other galilean satellites may also leave footprints, and the presence or absence of such footprints should illuminate the underlying physical mechanism by revealing the strengths of the currents linking the satellites to Jupiter. Here we report persistent, faint, far-ultraviolet emission from the jovian footprints of Ganymede and Europa. We also show that Io's magnetic footprint extends well beyond the immediate vicinity of Io's flux-tube interaction with Jupiter, and much farther than predicted theoretically; the emission persists for several hours downstream. We infer from these data that Ganymede and Europa have persistent interactions with Jupiter's magnetic field despite their thin atmospheres.
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Affiliation(s)
- J T Clarke
- Boston University, 725 Commonwealth Avenue, Boston, Massachusetts 02215, USA.
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23
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Gladstone GR, Waite JH, Grodent D, Lewis WS, Crary FJ, Elsner RF, Weisskopf MC, Majeed T, Jahn JM, Bhardwaj A, Clarke JT, Young DT, Dougherty MK, Espinosa SA, Cravens TE. A pulsating auroral X-ray hot spot on Jupiter. Nature 2002; 415:1000-3. [PMID: 11875561 DOI: 10.1038/4151000a] [Citation(s) in RCA: 158] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Jupiter's X-ray aurora has been thought to be excited by energetic sulphur and oxygen ions precipitating from the inner magnetosphere into the planet's polar regions. Here we report high-spatial-resolution observations that demonstrate that most of Jupiter's northern auroral X-rays come from a 'hot spot' located significantly poleward of the latitudes connected to the inner magnetosphere. The hot spot seems to be fixed in magnetic latitude and longitude and occurs in a region where anomalous infrared and ultraviolet emissions have also been observed. We infer from the data that the particles that excite the aurora originate in the outer magnetosphere. The hot spot X-rays pulsate with an approximately 45-min period, a period similar to that reported for high-latitude radio and energetic electron bursts observed by near-Jupiter spacecraft. These results invalidate the idea that jovian auroral X-ray emissions are mainly excited by steady precipitation of energetic heavy ions from the inner magnetosphere. Instead, the X-rays seem to result from currently unexplained processes in the outer magnetosphere that produce highly localized and highly variable emissions over an extremely wide range of wavelengths.
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Affiliation(s)
- G R Gladstone
- Southwest Research Institute, San Antonio, Texas 78228, USA.
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Mauk BH, Clarke JT, Grodent D, Waite JH, Paranicas CP, Williams DJ. Transient aurora on Jupiter from injections of magnetospheric electrons. Nature 2002; 415:1003-5. [PMID: 11875562 DOI: 10.1038/4151003a] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Energetic electrons and ions that are trapped in Earth's magnetosphere can suddenly be accelerated towards the planet. Some dynamic features of Earth's aurora (the northern and southern lights) are created by the fraction of these injected particles that travels along magnetic field lines and hits the upper atmosphere. Jupiter's aurora appears similar to Earth's in some respects; both appear as large ovals circling the poles and both show transient events. But the magnetospheres of Jupiter and Earth are so different---particularly in the way they are powered---that it is not known whether the magnetospheric drivers of Earth's aurora also cause them on Jupiter. Here we show a direct relationship between Earth-like injections of electrons in Jupiter's magnetosphere and a transient auroral feature in Jupiter's polar region. This relationship is remarkably similar to what happens at Earth, and therefore suggests that despite the large differences between planetary magnetospheres, some processes that generate aurorae are the same throughout the Solar System.
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Affiliation(s)
- B H Mauk
- The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, Maryland 20723, USA.
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25
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Choong K, Clarke JT, Cutz E, Pollit RJ, Olpin SE. Lethal cardiac tachyarrhythmia in a patient with neonatal carnitine-acylcarnitine translocase deficiency. Pediatr Dev Pathol 2001; 4:573-9. [PMID: 11826365 DOI: 10.1007/s10024001-0101-7] [Citation(s) in RCA: 13] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2001] [Accepted: 06/22/2001] [Indexed: 10/26/2022]
Abstract
Carnitine-acylcarnitine translocase (CACT) deficiency is an inherited defect of the co-transport of free and esterified carnitine across the inner mitochondrial membrane. We report a case of CACT deficiency in a newborn who died at 72 h of age from severe, intractable cardiac tachyarrhythmia, despite an improvement in his neurological and biochemical status. Postmortem examination showed marked steatosis of myocardium, liver, and kidney. In addition, electron microscopic studies showed virtually complete elimination of mitochondria from cardiomyocytes. It appears that the correction of the acute metabolic derangements in this condition may not prevent rapid progression to death, suggesting that the rhythm disturbances in CACT deficiency result from prior and ongoing accumulation of toxic metabolites, rather than from an acute metabolic derangement. Furthermore, we speculate that the choice of anti-arrhythmic agent in this patient may paradoxically have contributed to his death.
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Affiliation(s)
- K Choong
- Department of Pediatrics, Division of Neonatology, Hospital for Sick Children and University of Toronto, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada
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26
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Clarke JT, Amato D, Deber RB. Managing public payment for high-cost, high-benefit treatment: enzyme replacement therapy for Gaucher's disease in Ontario. CMAJ 2001; 165:595-6. [PMID: 11563212 PMCID: PMC81418] [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: 02/21/2023] Open
Affiliation(s)
- J T Clarke
- Department of Pediatrics, Hospital for Sick Children, Department of Health Administration, University of Toronto, Toronto, Ont.
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Abstract
Two brothers with a painful neuropathy as a component of late-onset GM2 gangliosidosis of the Sandhoff type are presented. A dramatic response of the severe dysesthesias to amitriptyline and gabapentin is described. Symptomatic sensory neuropathy may be a component of late-onset GM2 gangliosidosis.
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Affiliation(s)
- G C Chow
- Division of Neurology, University of Toronto and The Hospital for Sick Children, Toronto, Ontario, Canada
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28
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Waite JH, Gladstone GR, Lewis WS, Goldstein R, McComas DJ, Riley P, Walker RJ, Robertson P, Desai S, Clarke JT, Young DT. An auroral flare at Jupiter. Nature 2001; 410:787-9. [PMID: 11298440 DOI: 10.1038/35071018] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Jupiter's aurora is the most powerful in the Solar System. It is powered largely by energy extracted from planetary rotation, although there seems also to be a contribution from the solar wind. This contrasts with Earth's aurora, which is generated through the interaction of the solar wind with the magnetosphere. The major features of Jupiter's aurora (based on far-ultraviolet, near-infrared and visible-wavelength observations) include a main oval that generally corotates with the planet and a region of patchy, diffuse emission inside the oval on Jupiter's dusk side. Here we report the discovery of a rapidly evolving, very bright and localized emission poleward of the northern main oval, in a region connected magnetically to Jupiter's outer magnetosphere. The intensity of the emission increased by a factor of 30 within 70 s, and then decreased on a similar timescale, all captured during a single four-minute exposure. This type of flaring emission has not previously been reported for Jupiter (similar, but smaller, transient events have been observed at Earth), and it may be related directly to changes in the solar wind.
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Affiliation(s)
- J H Waite
- Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109, USA.
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29
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Abstract
GM2-gangliosidosis (McKusick 268800 and 272800) is a rare hereditary, progressive disorder of ganglioside metabolism caused by deficiency of lysosomal beta-hexosaminidase (EC 3.2.1.52) activity. It is characterized by severe central nervous system involvement. Involvement of the peripheral and autonomic nervous system has been suspected but rarely documented in published case reports in the chronic form of the disease. Four patients, aged 24-29 years, with chronic GM2-gangliosidosis were examined prospectively for evidence of peripheral and autonomic nervous system dysfunction. All had nerve conduction studies, sympathetic skin responses and cardiac monitoring during the head tilt-table test. Three patients had objective evidence of autonomic dysfunction with abnormal sympathetic nervous skin responses and axonal sensorimotor polyneuropathy. None of the patients had evidence of significant cardiovascular autonomic dysfunction on the head tilt-table test. The peripheral and autonomic nervous system may be involved in patients with chronic GM2-gangliosidosis. In some cases, this may be clinically significant. On the other hand, cardiovascular autonomic instability is apparently not a significant problem in young adult patients with the disease.
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Affiliation(s)
- M S Salman
- Division of Neurology, University of Toronto and Hospital for Sick Children, ON, Canada.
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30
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Petroulakis E, Cao Z, Clarke JT, Mahuran DJ, Lee G, Triggs-Raine B. W474C amino acid substitution affects early processing of the alpha-subunit of beta-hexosaminidase A and is associated with subacute G(M2) gangliosidosis. Hum Mutat 2000; 11:432-42. [PMID: 9603435 DOI: 10.1002/(sici)1098-1004(1998)11:6<432::aid-humu3>3.0.co;2-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Mutations in the HEXA gene, encoding the alpha-subunit of beta-hexosaminidase A (Hex A), that abolish Hex A enzyme activity cause Tay-Sachs disease (TSD), the fatal infantile form of G(M2) gangliosidosis, Type 1. Less severe, subacute (juvenile-onset) and chronic (adult-onset) variants are characterized by a broad spectrum of clinical manifestations and are associated with residual levels of Hex A enzyme activity. We identified a 1422 G-->C (amino acid W474C) substitution in the first position of exon 13 of HEXA of a non-Jewish proband who manifested a subacute variant of G(M2) gangliosidosis. On the second maternally inherited allele, we identified the common infantile disease-causing 4-bp insertion, +TATC 1278, in exon 11. Pulse-chase analysis using proband fibroblasts revealed that the W474C-containing alpha-subunit precursor was normally synthesized, but not phosphorylated or secreted, and the mature lysosomal alpha-subunit was not detected. When the W474C-containing alpha-subunit was transiently co-expressed with the beta-subunit to produce Hex A (alphabeta) in COS-7 cells, the mature alpha-subunit was present, but its level was much lower than that from normal alpha-subunit transfections, although higher than in those cells transfected with an alpha-subunit associated with infantile TSD. Furthermore, the precursor level of the W474C alpha-subunit was found to accumulate in comparison to the normal alpha-subunit precursor levels. We conclude that the 1422 G-->C mutation is the cause of Hex A enzyme deficiency in the proband. The resulting W474C substitution clearly interferes with alpha-subunit processing, but because the base substitution falls at the first position of exon 13, aberrant splicing may also contribute to Hex A deficiency in this proband.
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Affiliation(s)
- E Petroulakis
- Department of Biochemistry and Molecular Biology, University of Manitoba, Winnipeg, Canada
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31
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Zhang S, Bagshaw R, Hilson W, Oho Y, Hinek A, Clarke JT, Callahan JW. Characterization of beta-galactosidase mutations Asp332-->Asn and Arg148-->Ser, and a polymorphism, Ser532-->Gly, in a case of GM1 gangliosidosis. Biochem J 2000; 348 Pt 3:621-32. [PMID: 10839995 PMCID: PMC1221106] [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: 02/16/2023]
Abstract
We have identified and characterized three missense mutations in a patient with type 1 G(M1) gangliosidosis, namely a substitution of G for A at nucleotide position 1044 (G1044-->A; in exon 10) on one allele, which converts Asp(332) into asparagine, and both a mutation (C492-->A in exon 4, leading to the amino acid change of Arg(148)-->Ser) and a polymorphism (A1644-->G in exon 15, leading to a change of Ser(532)-->Gly) on the other allele. This patient had less than 1% residual beta-galactosidase activity and minimally detectable levels of immunoreactive beta-galactosidase protein in fibroblasts. To account for the above findings, a series of expression and immunolocalization studies were undertaken to assess the impact of each mutation. Transient overexpression in COS-1 cells of cDNAs encoding Asp(332)Asn, Arg(148)Ser and Ser(532)Gly mutant beta-galactosidases produced abundant amounts of precursor beta-galactosidase, with activities of 0, 84 and 81% compared with the cDNA clone for wild-type beta-galactosidase (GP8). Since the level of vector-driven expression is much less in Chinese hamster ovary (CHO) cells than in COS-1 cells, and we knew that exogenous beta-galactosidase undergoes lysosomal processing when expressed in these cells, transient expression studies were performed of Arg(148)Ser and Ser(532)Gly, which yielded active forms of the enzyme. In this case, the Arg(148)Ser and Ser(532)Gly products gave rise to 11% and 86% of the control activity respectively. These results were not unexpected, since the Arg(148)Ser mutation introduced a major conformational change into the protein, and we anticipated that it would be degraded in the endoplasmic reticulum (ER), whereas the polymorphism was expected to produce near-normal activity. To examine the effect of the Asp(332)Asn mutation on the catalytic activity, we isolated CHO clones permanently transfected with the Asp(332)Asn and Asp(332)Glu constructs, purified the enzymes by substrate-analogue-affinity chromatography, and determined their kinetic parameters. The V(max) values of both mutant recombinant enzymes were markedly reduced (less than 0.9% of the control), and the K(m) values were unchanged compared with the corresponding wild-type enzyme isolated at the same time. Both the Arg(148)Ser beta-galactosidase in CHO cells and Asp(332)Asn beta-galactosidases (in COS-1 and CHO cells) produced abundant immunoreaction in the perinuclear area, consistent with localization in the ER. A low amount was detected in lysosomes. Incubation of patient fibroblasts in the presence of leupeptin, which reduces the rate of degradation of lysosomal beta-galactosidase by thiol proteases, had no effect on residual enzyme activity, and immunostaining was again detected largely in the perinuclear area (localized to the ER) with much lower amounts in the lysosomes. In summary, the Arg(148)Ser mutation has no effect on catalytic activity, whereas the Asp(332)Asn mutation seriously reduces catalytic activity, suggesting that Asp(332) might play a role in the active site. Immunofluorescence studies indicate the expressed mutant proteins with Arg(148)Ser and Asp(332)Asn mutations are held up in the ER, where they are probably degraded, resulting in only minimum amounts of the enzyme becoming localized in the lysosomes. These results are completely consistent with findings in the cultured fibroblasts. Our results imply that most of the missense mutations described in G(M1) gangliosidosis to date have little effect on catalytic activity, but do affect protein conformation such that the resulting protein cannot be transported out of the ER and fails to arrive in the lysosome. This accounts for the minimal amounts of enzyme protein and activity seen in most G(M1) gangliosidosis patient fibroblasts.
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Affiliation(s)
- S Zhang
- Research Institute, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, Canada M5G 1X8
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32
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Abstract
Mucolipidosis type III (ML-III) is a lysosomal storage disease often presenting with joint involvement. We report the MRI appearance of the hips in two siblings with ML-III showing abnormal signal intensity within the hips with increased synovial thickness. Although the etiology is uncertain this may reflect a fibrous response to ML-III.
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Affiliation(s)
- C E Wihlborg
- Department of Diagnostic Imaging, Hospital for Sick Children, Toronto, Ontario, Canada
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33
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Abstract
It has been postulated that the significant incidence of learning disabilities in well-treated patients with phenylketonuria (PKU) may be due, in part, to reduced production of neurotransmitters as a result of deficient tyrosine transport across the neuronal cell membrane. Hypotyrosinemia has been reported in treated and untreated PKU but virtually no data are available. We decided to examine this in our patient population and to compare it with the published norms, patient data from our hospital clinical biochemical laboratory database, and a group of normal children and adolescents in a private pediatric practice. We found that the mean nonfasting plasma tyrosine in 99 classical PKU patients was 41.1 micromol/L, in 26 mild (atypical) PKU patients 53.3 micromol/L, and in 35 non-PKU mild hyperphenylalaninemia patients 66.6 micromol/L. This compared to nonfasting plasma tyrosine levels in 102 non-PKU subjects of 64.0 micromol/L in our hospital biochemistry database, 69.1 micromol/L in 58 volunteers in the private office practice, and 64-78.8 micromol/L in infants, children, and adolescents in the literature review. Our data support the previously undocumented statements in the literature that plasma tyrosine levels are low in PKU.
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Affiliation(s)
- W B Hanley
- Division of Clinical & Biochemical Genetics, The Hospital for Sick Children, Toronto, Ontario, Canada.
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34
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Affiliation(s)
- M J Nowaczyk
- Department of Molecular Medicine and Pathology, McMaster University, Hamilton, Ontario, Canada.
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35
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Abstract
Whether specific cognitive deficits related to frontal-lobe dysfunction that have been reported in individuals with phenylketonuria (PKU) are also characteristic of mild hyperphenylalaninemia (MHP) was investigated. Tests of executive function and control tasks not assessing executive function were administered to a group of individuals with MHP and a group without MHP, similar in age, gender, and IQ. Tests of academic skills and behavior-rating questionnaires were also administered to the group with MHP. No group differences were found for any measure, suggesting that the mild elevations of phenylalanine in individuals with MHP are not sufficient to produce behavioral and cognitive impairments characteristic of PKU.
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Affiliation(s)
- M L Smith
- University of Toronto at Mississauga.
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Abstract
Tyrosine (Tyr) is an essential amino acid in phenylketonuria (PKU) because of the limited hydroxylation of phenylalanine (Phe) to Tyr. The recommended intakes for Tyr in PKU are at least five times the recommended phenylalanine intakes. This suggests that Phe and Tyr contribute approximately 20 and 80%, respectively, of the aromatic amino acid (AAA) requirement (REQ). In animals and normal humans, dietary Tyr was shown to spare 40-50% of the Phe requirement, proportions that reflect dietary and tissue protein composition. We tested the hypothesis that the Tyr REQ in PKU would account for 45% of the total AAA REQ by indicator amino acid oxidation (IAAO). Tyr REQ was determined in five children with PKU by examining the effect of varying dietary Tyr intake on lysine oxidation and the appearance of (13)CO(2) in breath (F(13)CO(2)) under dietary conditions of adequate energy, protein (1.5 g x kg(-1) x day(-1)), and phenylalanine (25 mg x kg(-1) x day(-1)). Lysine oxidation and F(13)CO(2) were determined using a primed 4-h oral equal-dose infusion of L-[1-(13)C]lysine. Lysine oxidation and F(13)CO(2) decreased linearly as Tyr intake increased, to a break point that was interpreted as the mean dietary Tyr requirement (16.3 and 19.2 mg x kg(-1) x day(-1), respectively). At Tyr intakes of >16.3 and 19.2 mg x kg(-1) x day(-1), lysine oxidation and F(13)CO(2), respectively, were low and constant. This represents 40.4 and 44.4%, respectively, of the total AAA intake. The current recommendations for Tyr intake in PKU patients appear to be overestimated by a factor of approximately 5. This study is the first application of the IAAO technique in a pediatric population and in humans with an inborn error of metabolism.
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Affiliation(s)
- R Bross
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario M5S 3E2
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Clarke JT. Professional norms in the practice of medical genetics. Health Law J 1999; 3:131-51. [PMID: 10569872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Affiliation(s)
- J T Clarke
- Department of Genetics and Pediatrics, Hospital for Sick Children, Toronto, Ontario
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Clarke JT, Skinner WR, Vincent MB, Irgang T, Suratkal V, Grassl H, Trauger JT. Laboratory studies of alkali metal filter deposition, ultraviolet transmission, and visible blocking. Appl Opt 1999; 38:1803-1813. [PMID: 18305811 DOI: 10.1364/ao.38.001803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Far-ultraviolet alkali metal or Wood's filters have been produced and tested supporting the production of a flight filter for the Wide Field Planetary Camera 2 on the Hubble Space Telescope. Sodium layers 0.5-1-microm thick transmit up to 40% in the ultraviolet while efficiently blocking visible wavelengths. The prevention of visible pinholes is assisted by a clean, sleek-free surface and a cooled substrate during deposition. The coatings are stabilized efficiently by a bismuth overcoating whose transmission spectrum is presented. We also report for the first time, to our knowledge, the first demonstrated long-wavelength cutoff from a lithium filter, with a shorter cutoff wavelength than sodium and potentially higher stability for astronomical imaging.
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Affiliation(s)
- J T Clarke
- Space Physics Research Laboratory, University of Michigan, 2455 Hayward, Ann Arbor, Michigan 48109-2143, USA.
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MacKenzie JJ, Amato D, Clarke JT. Enzyme replacement therapy for Gaucher's disease: the early Canadian experience. CMAJ 1998; 159:1273-8. [PMID: 9861225 PMCID: PMC1229823] [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: 02/09/2023] Open
Abstract
BACKGROUND The management of severe Gaucher's disease was dramatically improved by the development of enzyme replacement therapy. However, this treatment is very costly (currently about $21,000 per infusion for adults at the starting dose recommended by the manufacturer). The goal of this study was to determine how enzyme replacement therapy was being prescribed and financially supported in various parts of Canada. In addition, demographic and outcome information was elicited. METHODS Prescribing physicians were identified through professional associations and with the help of the manufacturer of the enzyme preparations used for the treatment of Gaucher's disease. The physicians were surveyed by questionnaire in July 1995. The study included all patients in Canada who had received enzyme replacement therapy for Gaucher's disease before July 1, 1995. RESULTS A total of 25 patients (15 children and 10 adults) with type 1 Gaucher's disease, the common nonneuronopathic variant of the disease, were receiving enzyme replacement therapy by the end of 1995. The indications for treatment included massive splenomegaly, growth failure, and severe bony, hematologic and pulmonary complications of the disease; no patients with mild disease were receiving treatment. Treatment regimens varied markedly (from 12 to 160 units of enzyme/kg per month). All the patients were reported to have responded well to therapy, based on serial measurements of hematologic indices, liver and spleen volumes, and numbers of bony crises as well as patients' subjective impressions. Financial support for therapy varied markedly from one province to another. None of the reporting physicians was aware of any patients with severe Gaucher's disease who were denied therapy as a result of inability to pay for the medication. Various agencies provided financial support for therapy, including both federal and provincial governments, private insurance carriers and the commercial supplier of the enzyme. In Ontario provincial health care officials accepted the development, by a multidisciplinary panel of medical experts, of formal guidelines for determining eligibility, on the basis of objective medical criteria, for reimbursement for enzyme replacement treatment. INTERPRETATION Although some differences were found across the country with respect to the details of treatment, the indications for enzyme replacement therapy and the selection of severely affected patients were similar in the various provinces. However, financial support was inconsistent and varied among provinces and patients. This will prove to be a challenge in future, not only with respect to this disease but also for other diseases for which effective, expensive therapy has been developed.
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Affiliation(s)
- J J MacKenzie
- Department of Pediatrics, Queen's University, Kingston, Ont
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Nowaczyk MJ, Hughes HE, Costa T, Clarke JT. Severe prenatal growth retardation, dysmorphic features, pigmentary retinopathy, and generalized absence of subcutaneous tissues: a new entity? Clin Dysmorphol 1998; 7:263-8. [PMID: 9823492 DOI: 10.1097/00019605-199810000-00005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We report a girl with severe prenatal and postnatal growth retardation, congenital generalized absence of subcutaneous tissue, and facial and somatic changes with some similarities to Wiedemann-Rautenstrauch syndrome (WRS). However, the patient's condition is sufficiently different from those reported previously to suggest that this patient represents a new syndrome. The abnormalities observed in this patient overlap with those of WRS, Cockayne syndrome, type A (CSA), and osteodysplastic primordial dwarfism type III (OPD III), but also include choanal atresia and pigmentary retinopathy.
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Affiliation(s)
- M J Nowaczyk
- Division of Clinical Genetics, Hospital for Sick Children, Toronto, Ontario, Canada.
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41
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Clarke JT, Ballester G, Trauger J, Ajello J, Pryor W, Tobiska K, Connerney JEP, Gladstone GR, Waite JH, Ben Jaffel L, Gérard JC. Hubble Space Telescope imaging of Jupiter's UV aurora during the Galileo orbiter mission. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98je01130] [Citation(s) in RCA: 155] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Trauger JT, Clarke JT, Ballester GE, Evans RW, Burrows CJ, Crisp D, Gallagher JS, Griffiths RE, Hester JJ, Hoessel JG, Holtzman JA, Krist JE, Mould JR, Sahai R, Scowen PA, Stapelfeldt KR, Watson AM. Saturn's hydrogen aurora: Wide field and planetary camera 2 imaging from the Hubble Space Telescope. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98je01324] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Nowaczyk MJ, Lehotay DC, Platt BA, Fisher L, Tan R, Phillips H, Clarke JT. Ethylmalonic and methylsuccinic aciduria in ethylmalonic encephalopathy arise from abnormal isoleucine metabolism. Metabolism 1998; 47:836-9. [PMID: 9667231 DOI: 10.1016/s0026-0495(98)90122-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [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: 11/18/2022]
Abstract
Ethylmalonic encephalopathy (EE), an organic aciduria of unknown etiology characterized by developmental delay, hypotonia, and vascular instability associated with lactic acidemia and urinary excretion of ethylmalonic acid (EMA) and methylsuccinic acid (MSA), has been described in 11 patients. To test the possibility that the underlying biochemical defect involves isoleucine catabolism, we determined the response to oral L-isoleucine (IIe) load (150 mg/kg) in a 5-year-old girl with EE and in three healthy, age- and sex-matched controls. Following IIe load in the patient, there was accumulation of 2-methylbutyrylglycine (2-MBG) and a delayed and lower peak urinary excretion of tiglylglycine (TGL), suggesting a partial defect in 2-methyl-branched chain acylcoenzyme A dehydrogenase (2M-BCAD). In vitro measurements 2M-BCAD activity in cultured skin fibroblasts from patients with EE have been reported to be normal. Our results show that isoleucine is a source for the elevated EMA and MSA in patients with EE, and suggest a functional, possibly secondary, deficiency of activity of 2M-BCAD in vivo.
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Affiliation(s)
- M J Nowaczyk
- Department of Pediatrics, Hospital for Sick Children and University of Toronto, Ontario, Canada
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Carbone MA, MacKay N, Ling M, Cole DE, Douglas C, Rigat B, Feigenbaum A, Clarke JT, Haworth JC, Greenberg CR, Seargeant L, Robinson BH. Amerindian pyruvate carboxylase deficiency is associated with two distinct missense mutations. Am J Hum Genet 1998; 62:1312-9. [PMID: 9585612 PMCID: PMC1377163 DOI: 10.1086/301884] [Citation(s) in RCA: 34] [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: 11/04/2022] Open
Abstract
We characterized the pyruvate carboxylase (PC) gene by PCR amplification, subcloning, and sequencing. The coding region has 19 exons and 18 introns spanning approximately 16 kb of genomic DNA. Screening both the cDNA and the gene of individuals with the simple A form of PC deficiency revealed an 1828G-->A missense mutation in 11 Ojibwa and 2 Cree patients and a 2229G-->T transversion mutation in 2 brothers of Micmac origin. Carrier frequency may be as high as 1/10 in some groupings. The two point mutations are located in a region of homology conserved among yeast, rat, and human PC, in the vicinity of the carboxylation domain of the enzyme. These data provide the first characterization of the human PC gene structure, the identification of common pathogenic mutations, and the demonstration of a founder effect in the Ojibwa and Cree patients.
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Affiliation(s)
- M A Carbone
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
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45
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Christodoulou J, Danks DM, Sarkar B, Baerlocher KE, Casey R, Horn N, Tümer Z, Clarke JT. Early treatment of Menkes disease with parenteral copper-histidine: long-term follow-up of four treated patients. Am J Med Genet 1998; 76:154-64. [PMID: 9511979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We report on the long-term clinical course of 4 boys with Menkes disease, treated from early infancy with parenteral copper-histidine, with follow-up over 10-20 years. Three of the 4 had male relatives with a severe clinical course compatible with classical Menkes disease. As a consequence of early treatment, our patients have normal or near-normal intellectual development, but have developed many of the more severe somatic abnormalities of the related disorder, occipital horn syndrome, including severe orthostatic hypotension in 2. In addition, 1 boy developed a previously unreported anomaly, namely, massive splenomegaly and hypersplenism as a consequence of a splenic artery aneurysm. Previously reported molecular studies in 2 of these patients had shown gene defects which would have predicted a truncated and probably nonfunctional gene product. Despite the favorable effects on the neurological symptoms, parenteral copper treatment for Menkes disease should still be regarded as experimental. The development of more effective treatments must await a more precise delineation of the role which the Menkes protein plays in intracellular copper trafficking.
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Affiliation(s)
- J Christodoulou
- Division of Clinical Genetics, Hospital for Sick Children, Toronto, Ontario, Canada
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Smith ML, Hanley WB, Clarke JT, Klim P, Schoonheyt W, Austin V, Lehotay DC. Randomised controlled trial of tyrosine supplementation on neuropsychological performance in phenylketonuria. Arch Dis Child 1998; 78:116-21. [PMID: 9579151 PMCID: PMC1717450 DOI: 10.1136/adc.78.2.116] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [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: 12/29/2022]
Abstract
OBJECTIVE To test the efficacy of tyrosine supplementation, as an adjunct to dietary treatment, on neuropsychological test performance in individuals with phenylketonuria. DESIGN A randomised controlled trial of tyrosine supplementation using a double blind crossover procedure with three four week phases. SETTING The Hospital for Sick Children, Toronto. PARTICIPANTS 21 individuals with phenylketonuria (ages 6 to 28 years, mean 11.3). INTERVENTION Participants were given 100 mg/kg body weight/d of L-tyrosine or L-alanine (placebo). RESULTS At baseline, performance on several of the neuropsychological test measures was correlated with tyrosine levels. Dietary supplements of tyrosine increased plasma tyrosine concentrations; however, no change in test performance was found across the tyrosine and placebo phases of the study. CONCLUSIONS Tyrosine supplementation of this type does not appear to alter neuropsychological performance in individuals with phenylketonuria.
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Affiliation(s)
- M L Smith
- Department of Psychology, University of Toronto, Mississauga, Ontario, Canada.
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47
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Nowaczyk MJ, Blaser SI, Clarke JT. Central nervous system malformations in ethylmalonic encephalopathy. Am J Med Genet 1998; 75:292-6. [PMID: 9475600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Central nervous system malformations have been reported in a number of inherited enzyme defects. Ethylmalonic encephalopathy, an organic aciduria of unknown pathogenesis, has not been reported previously in association with brain or spinal cord malformations. We report on 2 sibs with confirmed ethylmalonic encephalopathy and malformations of the central nervous system; one with tethered cord, the other with cerebellar tonsillar ectopia (Chiari I malformation).
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Affiliation(s)
- M J Nowaczyk
- Department of Pediatrics, Hospital for Sick Children, University of Toronto, Ontario, Canada.
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Cantor WJ, Daly P, Iwanochko M, Clarke JT, Cusimano RJ, Butany J. Cardiac transplantation for Fabry's disease. Can J Cardiol 1998; 14:81-4. [PMID: 9487277] [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: 02/06/2023] Open
Abstract
Fabry's disease is a rare cause of cardiomyopathy. There are no previous reported cases of cardiac transplantation for end-stage cardiomyopathy secondary to Fabry's disease. Recurrence of disease in allografts following renal transplantation has been documented, but the course following heart transplantation is not known. A 53-year-old female presented with congestive heart failure and was found to have end-stage restrictive cardiomyopathy secondary to Fabry's disease, as diagnosed by endomyocardial biopsy. She underwent cardiac transplantation. Eight weeks post-transplantation, electron microscopy of an endomyocardial biopsy specimen showed concentric lamellar inclusions within myocytes similar to inclusions seen in the preoperative biopsy and the explanted heart. However, subsequent biopsies up to one year after heart transplantation did not show any such inclusions. There has been no clinical evidence of Fabry's cardiomyopathy. Heart transplantation is a viable option for end-stage Fabry's cardiomyopathy. However, long term follow-up is required to determine clinical outcome.
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Affiliation(s)
- W J Cantor
- Division of Cardiology, Toronto Hospital, Ontario
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Abstract
We report the results of a near total myeloablation in preparation for bone marrow transplantation in a boy with minimal symptoms of X-linked adrenoleukodystrophy. Severe cerebral X-linked adrenoleukodystrophy developed in the patient after failure of bone marrow transplantation. This experience suggests that immunotherapy alone is not responsible for the improvement observed in some patients with X-ALD after BMT.
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Affiliation(s)
- M J Nowaczyk
- Department of Pediatrics, Hospital for Sick Children, Ontario, Canada
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Affiliation(s)
- A Owayed
- Department of Pediatrics, Hospital for Sick Children, Toronto, Ontario, Canada
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