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Dimitriadis SI, Perry G, Lancaster TM, Tansey KE, Singh KD, Holmans P, Pocklington A, Davey Smith G, Zammit S, Hall J, O’Donovan MC, Owen MJ, Jones DK, Linden DE. Genetic risk for schizophrenia is associated with increased proportion of indirect connections in brain networks revealed by a semi-metric analysis: evidence from population sample stratified for polygenic risk. Cereb Cortex 2023; 33:2997-3011. [PMID: 35830871 PMCID: PMC10016061 DOI: 10.1093/cercor/bhac256] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [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: 02/16/2022] [Revised: 05/30/2022] [Accepted: 05/31/2022] [Indexed: 02/02/2023] Open
Abstract
Research studies based on tractography have revealed a prominent reduction of asymmetry in some key white-matter tracts in schizophrenia (SCZ). However, we know little about the influence of common genetic risk factors for SCZ on the efficiency of routing on structural brain networks (SBNs). Here, we use a novel recall-by-genotype approach, where we sample young adults from a population-based cohort (ALSPAC:N genotyped = 8,365) based on their burden of common SCZ risk alleles as defined by polygenic risk score (PRS). We compared 181 individuals at extremes of low (N = 91) or high (N = 90) SCZ-PRS under a robust diffusion MRI-based graph theoretical SBN framework. We applied a semi-metric analysis revealing higher SMR values for the high SCZ-PRS group compared with the low SCZ-PRS group in the left hemisphere. Furthermore, a hemispheric asymmetry index showed a higher leftward preponderance of indirect connections for the high SCZ-PRS group compared with the low SCZ-PRS group (PFDR < 0.05). These findings might indicate less efficient structural connectivity in the higher genetic risk group. This is the first study in a population-based sample that reveals differences in the efficiency of SBNs associated with common genetic risk variants for SCZ.
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Affiliation(s)
- S I Dimitriadis
- Neuroscience and Mental Health Research Institute (NMHI), College of Biomedical and Life Sciences, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, College of Biomedical and Life Sciences, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
- Division of Psychological Medicine and Clinical Neurosciences, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff School of Medicine, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
- Neuroinformatics Group, School of Psychology, College of Biomedical and Life Sciences, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
| | - G Perry
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, College of Biomedical and Life Sciences, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
| | - T M Lancaster
- Neuroscience and Mental Health Research Institute (NMHI), College of Biomedical and Life Sciences, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, College of Biomedical and Life Sciences, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
- Department of Psychology, Bath University, Claverton Down BA2 7AY, Bath, Wales, UK
| | - K E Tansey
- MRC Integrative Epidemiology Unit (IEU), University of Bristol, Queens Road BS8 1QU, Bristol, Wales, UK
| | - K D Singh
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, College of Biomedical and Life Sciences, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
| | - P Holmans
- Division of Psychological Medicine and Clinical Neurosciences, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff School of Medicine, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
| | - A Pocklington
- Division of Psychological Medicine and Clinical Neurosciences, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff School of Medicine, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
| | - G Davey Smith
- MRC Integrative Epidemiology Unit (IEU), University of Bristol, Queens Road BS8 1QU, Bristol, Wales, UK
- Population Health Sciences, Bristol Medical School, University of Bristol, 1-5 Whiteladies Road BS8 1NU, Bristol, Wales, UK
| | - S Zammit
- Division of Psychological Medicine and Clinical Neurosciences, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff School of Medicine, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
- Population Health Sciences, Bristol Medical School, University of Bristol, 1-5 Whiteladies Road BS8 1NU, Bristol, Wales, UK
| | - J Hall
- Neuroscience and Mental Health Research Institute (NMHI), College of Biomedical and Life Sciences, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
- Division of Psychological Medicine and Clinical Neurosciences, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff School of Medicine, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
| | - M C O’Donovan
- Neuroscience and Mental Health Research Institute (NMHI), College of Biomedical and Life Sciences, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
- Division of Psychological Medicine and Clinical Neurosciences, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff School of Medicine, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
| | - M J Owen
- Neuroscience and Mental Health Research Institute (NMHI), College of Biomedical and Life Sciences, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
- Division of Psychological Medicine and Clinical Neurosciences, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff School of Medicine, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
| | - D K Jones
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, College of Biomedical and Life Sciences, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
| | - D E Linden
- Neuroscience and Mental Health Research Institute (NMHI), College of Biomedical and Life Sciences, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, College of Biomedical and Life Sciences, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
- Division of Psychological Medicine and Clinical Neurosciences, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff School of Medicine, Cardiff University, Maindy Road CF24 4HQ, Cardiff, Wales, UK
- Population Health Sciences, Bristol Medical School, University of Bristol, 1-5 Whiteladies Road BS8 1NU, Bristol, Wales, UK
- School for Mental Health and Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Universiteitssingel 40 UNS40 6229 ER, Maastricht, The Netherlands
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2
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Postans M, Parker GD, Lundell H, Ptito M, Hamandi K, Gray WP, Aggleton JP, Dyrby TB, Jones DK, Winter M. Uncovering a Role for the Dorsal Hippocampal Commissure in Recognition Memory. Cereb Cortex 2021; 30:1001-1015. [PMID: 31364703 PMCID: PMC7132945 DOI: 10.1093/cercor/bhz143] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [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: 12/05/2018] [Revised: 05/31/2019] [Accepted: 05/31/2019] [Indexed: 01/24/2023] Open
Abstract
The dorsal hippocampal commissure (DHC) is a white matter tract that provides interhemispheric connections between temporal lobe brain regions. Despite the importance of these regions for learning and memory, there is scant evidence of a role for the DHC in successful memory performance. We used diffusion-weighted magnetic resonance imaging (DW-MRI) and white matter tractography to reconstruct the DHC in both humans (in vivo) and nonhuman primates (ex vivo). Across species, our findings demonstrate a close consistency between the known anatomy and tract reconstructions of the DHC. Anterograde tract-tracer techniques also highlighted the parahippocampal origins of DHC fibers in nonhuman primates. Finally, we derived diffusion tensor MRI metrics from the DHC in a large sample of human subjects to investigate whether interindividual variation in DHC microstructure is predictive of memory performance. The mean diffusivity of the DHC correlated with performance in a standardized recognition memory task, an effect that was not reproduced in a comparison commissure tract—the anterior commissure. These findings highlight a potential role for the DHC in recognition memory, and our tract reconstruction approach has the potential to generate further novel insights into the role of this previously understudied white matter tract in both health and disease.
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Affiliation(s)
- M Postans
- Cardiff University Brain Research Imaging Centre, CF24 4HQ.,School of Psychology, CF10 3AS
| | - G D Parker
- Cardiff University Brain Research Imaging Centre, CF24 4HQ.,Experimental MRI Centre, School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| | - H Lundell
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, DK-2650, Denmark
| | - M Ptito
- School of Optometry, University of Montreal, H3T 1J4 Montreal, Canada.,Department of Neurology and Neurosurgery, Montreal Neurological Institute, H3A 2B4 Montreal, Canada
| | - K Hamandi
- Cardiff University Brain Research Imaging Centre, CF24 4HQ.,The Alan Richens Welsh Epilepsy Centre, Department of Neurology, University Hospital of Wales, Cardiff CF14 4XW, UK.,Institute of Psychological Medicine and Clinical Neurosciences.,Brain Repair And Intracranial Neurotherapeutics Unit, School of Medicine, Cardiff University, Cardiff CF24 4HQ, UK
| | - W P Gray
- Cardiff University Brain Research Imaging Centre, CF24 4HQ.,The Alan Richens Welsh Epilepsy Centre, Department of Neurology, University Hospital of Wales, Cardiff CF14 4XW, UK.,Institute of Psychological Medicine and Clinical Neurosciences.,Brain Repair And Intracranial Neurotherapeutics Unit, School of Medicine, Cardiff University, Cardiff CF24 4HQ, UK.,Department of Neurosurgery, Neurosciences Division, University Hospital Wales, Cardiff, CF14 4XW, UK
| | - J P Aggleton
- Cardiff University Brain Research Imaging Centre, CF24 4HQ.,School of Psychology, CF10 3AS
| | - T B Dyrby
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, DK-2650, Denmark.,Department of Applied Mathematics and Computer Science, Technical University of Denmark, Kongens Lyngby, Denmark, DK-2800
| | - D K Jones
- Cardiff University Brain Research Imaging Centre, CF24 4HQ.,School of Psychology, CF10 3AS.,Brain Repair And Intracranial Neurotherapeutics Unit, School of Medicine, Cardiff University, Cardiff CF24 4HQ, UK.,Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne 3000, Australia
| | - M Winter
- Cardiff University Brain Research Imaging Centre, CF24 4HQ.,School of Psychology, CF10 3AS.,Brain Repair And Intracranial Neurotherapeutics Unit, School of Medicine, Cardiff University, Cardiff CF24 4HQ, UK.,Department of Clinical Neuropsychology, University Hospital of Wales, Cardiff, CF14 4XW, UK
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3
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Griffin DW, Benzel WM, Fisher SC, Focazio MJ, Iwanowicz LR, Loftin KA, Reilly TJ, Jones DK. The presence of antibiotic resistance genes in coastal soil and sediment samples from the eastern seaboard of the USA. Environ Monit Assess 2019; 191:300. [PMID: 31254080 DOI: 10.1007/s10661-019-7426-z] [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] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 03/20/2019] [Indexed: 06/09/2023]
Abstract
Infections from antibiotic resistant microorganisms are considered to be one of the greatest global public health challenges that result in huge annual economic losses. While genes that impart resistance to antibiotics (AbR) existed long before the discovery and use of antibiotics, anthropogenic uses of antibiotics in agriculture, domesticated animals, and humans are known to influence the prevalence of these genes in pathogenic microorganisms. It is critical to understand the role that natural and anthropogenic processes have on the occurrence and distribution of antibiotic resistance in microbial populations to minimize health risks associated with exposures. As part of this research, 15 antibiotic resistance genes were analyzed in coastal sediments and soils along the eastern seaboard of the USA using presence/absence quantitative and digital polymerase chain reaction assays. Samples (53 soil and 192 sediment samples including 54 replicates) were collected from a variety of coastal settings where human and wildlife exposure is likely. At least one of the antibiotic resistance genes was detected in 76.4% of the samples. Samples that contained at least five or more antibiotic resistance genes (5.7%) where typically hydrologically down gradient of watersheds influenced by combined sewer outfalls (CSO). The most frequently detected antibiotic resistance target genes were found in 33.2%, 34.4%, and 42.2% of samples (target genes blaSHV, tetO, and aadA2, respectively). These data provide unique insight into potential exposure of AbR genes over a large geographical region of the eastern seaboard of the USA.
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Affiliation(s)
- Dale W Griffin
- USGS, 600 4th Street South, St. Petersburg, FL, 33701, USA.
| | - W M Benzel
- USGS, Box 25046, MS-973, Denver Federal Center, Denver, CO, 80225, USA
| | - S C Fisher
- USGS, 2045 Route 112, Coram, NY, 11727, USA
| | - M J Focazio
- USGS, 12201 Sunrise Valley Drive, Reston, VA, 20192, USA
| | - L R Iwanowicz
- USGS, 11649 Leetown Road, Kearneysville, WV, 25430, USA
| | - K A Loftin
- USGS, 1217 Biltmore Drive, Lawrence, KS, 66049, USA
| | - T J Reilly
- USGS, 12201 Sunrise Valley Drive, Reston, VA, 20192, USA
| | - D K Jones
- USGS, 2329 West Orton Circle, West Valley City, UT, 84119, USA
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4
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Jones DK, Alexander DC, Bowtell R, Cercignani M, Dell'Acqua F, McHugh DJ, Miller KL, Palombo M, Parker GJM, Rudrapatna US, Tax CMW. Microstructural imaging of the human brain with a 'super-scanner': 10 key advantages of ultra-strong gradients for diffusion MRI. Neuroimage 2018; 182:8-38. [PMID: 29793061 DOI: 10.1016/j.neuroimage.2018.05.047] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Revised: 05/17/2018] [Accepted: 05/18/2018] [Indexed: 12/13/2022] Open
Abstract
The key component of a microstructural diffusion MRI 'super-scanner' is a dedicated high-strength gradient system that enables stronger diffusion weightings per unit time compared to conventional gradient designs. This can, in turn, drastically shorten the time needed for diffusion encoding, increase the signal-to-noise ratio, and facilitate measurements at shorter diffusion times. This review, written from the perspective of the UK National Facility for In Vivo MR Imaging of Human Tissue Microstructure, an initiative to establish a shared 300 mT/m-gradient facility amongst the microstructural imaging community, describes ten advantages of ultra-strong gradients for microstructural imaging. Specifically, we will discuss how the increase of the accessible measurement space compared to a lower-gradient systems (in terms of Δ, b-value, and TE) can accelerate developments in the areas of 1) axon diameter distribution mapping; 2) microstructural parameter estimation; 3) mapping micro-vs macroscopic anisotropy features with gradient waveforms beyond a single pair of pulsed-gradients; 4) multi-contrast experiments, e.g. diffusion-relaxometry; 5) tractography and high-resolution imaging in vivo and 6) post mortem; 7) diffusion-weighted spectroscopy of metabolites other than water; 8) tumour characterisation; 9) functional diffusion MRI; and 10) quality enhancement of images acquired on lower-gradient systems. We finally discuss practical barriers in the use of ultra-strong gradients, and provide an outlook on the next generation of 'super-scanners'.
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Affiliation(s)
- D K Jones
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cardiff, CF24 4HQ, UK; School of Psychology, Faculty of Health Sciences, Australian Catholic University, Melbourne, Victoria, 3065, Australia.
| | - D C Alexander
- Centre for Medical Image Computing (CMIC), Department of Computer Science, UCL (University College London), Gower Street, London, UK; Clinical Imaging Research Centre, National University of Singapore, Singapore
| | - R Bowtell
- Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, UK
| | - M Cercignani
- Department of Psychiatry, Brighton and Sussex Medical School, Brighton, UK
| | - F Dell'Acqua
- Natbrainlab, Department of Neuroimaging, King's College London, London, UK
| | - D J McHugh
- Division of Informatics, Imaging and Data Sciences, The University of Manchester, Manchester, UK; CRUK and EPSRC Cancer Imaging Centre in Cambridge and Manchester, Cambridge and Manchester, UK
| | - K L Miller
- Oxford Centre for Functional MRI of the Brain, University of Oxford, Oxford, UK
| | - M Palombo
- Centre for Medical Image Computing (CMIC), Department of Computer Science, UCL (University College London), Gower Street, London, UK
| | - G J M Parker
- Division of Informatics, Imaging and Data Sciences, The University of Manchester, Manchester, UK; CRUK and EPSRC Cancer Imaging Centre in Cambridge and Manchester, Cambridge and Manchester, UK; Bioxydyn Ltd., Manchester, UK
| | - U S Rudrapatna
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cardiff, CF24 4HQ, UK
| | - C M W Tax
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cardiff, CF24 4HQ, UK
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Nadash P, Alan Miller E, Jones DK, Gusmano MK, Rosenbaum S. THE GOP’S TRANSFORMATION OF AMERICAN HEALTH CARE: THE STAKES FOR OLDER AMERICANS. Innov Aging 2018. [DOI: 10.1093/geroni/igy023.2355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- P Nadash
- University of Massachusetts Boston, Boston, Massachusetts, United States
| | - E Alan Miller
- University of Massachusetts Boston, Boston, MA, USA; Brown University, Providence, RI, USA
| | | | - M K Gusmano
- Rutgers University, New Brunswick, NJ, USA; The Hastings Center, Garrison, NY, USA
| | - S Rosenbaum
- The George Washington University, Washington, DC
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6
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Miller EA, Gusmano MK, Jones DK. AGING POLICY IN THE TRUMP ERA. Innov Aging 2018. [DOI: 10.1093/geroni/igy023.2351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- E A Miller
- University of Massachusetts Boston, Boston, Massachusetts
| | - M K Gusmano
- Rutgers University School of Public Health, New Brunswick, New Jersey
| | - D K Jones
- Boston University, Boston, Massachusetts
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7
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Jones DK, Luddington R, Higenbottam TW, Scott J, Cavarocchi N, Reardon D, Calvin J, Wallwork J. Changes in Factor VIII Proteins After Cardiopulmonary Bypass in Man Suggest Endothelial Damage. Thromb Haemost 2018. [DOI: 10.1055/s-0038-1647029] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Summary16 patients undergoing coronary artery bypass grafting using cardiopulmonary bypass (CPB) had blood samples taken at various times before, during and up to 1 week after surgery for estimation of beta-thromboglobulin (BTG), alpha- 1-antichymo- trypsin (ACT), factor VIII procoagulant protein (VIII:C), von Willebrand factor antigen (vWF:Ag) and ristocetin co-factor (vWFiRiCoF). vWF:Ag and vWF:RiCoF rose during and following surgery in a different manner to ACT. At 1 week there was a significantly disproportionate rise in vWF: Ag compared to vWFiRiCoF which suggested a degree of pulmonary endothelial damage.Prostacyclin, which was administered to 8 of the patients during CPB, reduced platelet activation as measured by a reduction in the release of BTG and also attenuated the consumption of VIII: C. It had no effect on pulmonary endothelial damage as measured by the ratio of vWF: Ag to vWF: RiCoF.
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Affiliation(s)
- D K Jones
- The Department of Respiratory Physiology, Papworth Hospital, Cambridge, England
| | - R Luddington
- The Department of Clinical Haematology, Addenbrookes Hospital, Cambridge, England
| | - T W Higenbottam
- The Department of Respiratory Physiology, Papworth Hospital, Cambridge, England
| | - J Scott
- The Department of Respiratory Physiology, Papworth Hospital, Cambridge, England
| | - N Cavarocchi
- The Department of Cardiothoracic Surgery, Papworth Hospital, Cambridge, England
| | - D Reardon
- The Department of Clinical Haematology, Addenbrookes Hospital, Cambridge, England
| | - J Calvin
- The Department of Biochemistry, Addenbrookes Hospital, Cambridge, England
| | - J Wallwork
- The Department of Cardiothoracic Surgery, Papworth Hospital, Cambridge, England
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8
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Stoler AB, Mattes BM, Hintz WD, Jones DK, Lind L, Schuler MS, Relyea RA. Effects of a common insecticide on wetland communities with varying quality of leaf litter inputs. Environ Pollut 2017; 226:452-462. [PMID: 28431762 DOI: 10.1016/j.envpol.2017.04.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 03/27/2017] [Accepted: 04/08/2017] [Indexed: 06/07/2023]
Abstract
Chemical contamination of aquatic systems often co-occurs with dramatic changes in surrounding terrestrial vegetation. Plant leaf litter serves as a crucial resource input to many freshwater systems, and changes in litter species composition can alter the attributes of freshwater communities. However, little is known how variation in litter inputs interacts with chemical contaminants. We investigated the ecological effects resulting from changes in tree leaf litter inputs to freshwater communities, and how those changes might interact with the timing of insecticide contamination. Using the common insecticide malathion, we hypothesized that inputs of nutrient-rich and labile leaf litter (e.g., elm [Ulmus spp.] or maple [Acer spp.]) would reduce the negative effects of insecticides on wetland communities relative to inputs of recalcitrant litter (e.g., oak [Quercus spp.]). We exposed artificial wetland communities to a factorial combination of three litter species treatments (elm, maple, and oak) and four insecticide treatments (no insecticide, small weekly doses of 10 μg L-1, and either early or late large doses of 50 μg L-1). Communities consisted of microbes, algae, snails, amphipods, zooplankton, and two species of tadpoles. After two months, we found that maple and elm litter generally induced greater primary and secondary production. Insecticides induced a reduction in the abundance of amphipods and some zooplankton species, and increased phytoplankton. In addition, we found interactive effects of litter species and insecticide treatments on amphibian responses, although specific effects depended on application regime. Specifically, with the addition of insecticide, elm and maple litter induced a reduction in gray tree frog survival, oak and elm litter delayed tree frog metamorphosis, and oak and maple litter reduced green frog tadpole mass. Our results suggest that attention to local forest composition, as well as the timing of pesticide application might help ameliorate the harmful effects of pesticides observed in freshwater systems.
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Affiliation(s)
- A B Stoler
- Darrin Fresh Water Institute, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
| | - B M Mattes
- Darrin Fresh Water Institute, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - W D Hintz
- Darrin Fresh Water Institute, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - D K Jones
- Darrin Fresh Water Institute, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - L Lind
- Darrin Fresh Water Institute, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - M S Schuler
- Darrin Fresh Water Institute, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - R A Relyea
- Darrin Fresh Water Institute, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
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9
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Ecker C, Andrews D, Dell'Acqua F, Daly E, Murphy C, Catani M, Thiebaut de Schotten M, Baron-Cohen S, Lai MC, Lombardo MV, Bullmore ET, Suckling J, Williams S, Jones DK, Chiocchetti A, Murphy DGM. Relationship Between Cortical Gyrification, White Matter Connectivity, and Autism Spectrum Disorder. Cereb Cortex 2016; 26:3297-309. [PMID: 27130663 PMCID: PMC4898679 DOI: 10.1093/cercor/bhw098] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Autism spectrum disorder (ASD) is a complex neurodevelopmental condition, which is accompanied by differences in gray matter neuroanatomy and white matter connectivity. However, it is unknown whether these differences are linked or reflect independent aetiologies. Using a multimodal neuroimaging approach, we therefore examined 51 male adults with ASD and 48 neurotypical controls to investigate the relationship between gray matter local gyrification (lGI) and white matter diffusivity in associated fiber tracts. First, ASD individuals had a significant increase in gyrification around the left pre- and post-central gyrus. Second, white matter fiber tracts originating and/or terminating in the cluster of increased lGI had a significant increase in axial diffusivity. This increase in diffusivity was predominantly observed in tracts in close proximity to the cortical sheet. Last, we demonstrate that the increase in lGI was significantly correlated with increased diffusivity of short tracts. This relationship was not significantly modulated by a main effect of group (i.e., ASD), which was more closely associated with gray matter gyrification than white matter diffusivity. Our findings suggest that differences in gray matter neuroanatomy and white matter connectivity are closely linked, and may reflect common rather than distinct aetiological pathways.
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Affiliation(s)
- C Ecker
- Department of Forensic and Neurodevelopmental Sciences, and the Sackler Institute for Translational Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College, London SE5 8AF, UK Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Goethe University, 60528 Frankfurt am Main, Germany
| | - D Andrews
- Department of Forensic and Neurodevelopmental Sciences, and the Sackler Institute for Translational Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College, London SE5 8AF, UK
| | - F Dell'Acqua
- Department of Forensic and Neurodevelopmental Sciences, and the Sackler Institute for Translational Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College, London SE5 8AF, UK
| | - E Daly
- Department of Forensic and Neurodevelopmental Sciences, and the Sackler Institute for Translational Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College, London SE5 8AF, UK
| | - C Murphy
- Department of Forensic and Neurodevelopmental Sciences, and the Sackler Institute for Translational Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College, London SE5 8AF, UK
| | - M Catani
- Department of Forensic and Neurodevelopmental Sciences, and the Sackler Institute for Translational Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College, London SE5 8AF, UK
| | - M Thiebaut de Schotten
- Department of Forensic and Neurodevelopmental Sciences, and the Sackler Institute for Translational Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College, London SE5 8AF, UK
| | - S Baron-Cohen
- Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge CB2 8AH, UK
| | - M C Lai
- Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge CB2 8AH, UK Child and Youth Mental Health Collaborative at the Centre or Addiction and Mental Health and The Hospital for Sick Children, Department of Psychiatry, University of Toronto, Toronto, Ontario, M6J 1H4, Canada Department of Psychiatry, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan 100, R.O.C
| | - M V Lombardo
- Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge CB2 8AH, UK Department of Psychology and Center for Applied Neuroscience, University of Cyprus, 1678 Nicosia, Cyprus
| | - E T Bullmore
- Brain Mapping Unit, Department of Psychiatry, University of Cambridge, Cambridge CB2 0SZ, UK
| | - J Suckling
- Brain Mapping Unit, Department of Psychiatry, University of Cambridge, Cambridge CB2 0SZ, UK
| | - S Williams
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College, London SE5 8AF, UK
| | - D K Jones
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff CF24 5HQ, UK
| | - A Chiocchetti
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Goethe University, 60528 Frankfurt am Main, Germany
| | - D G M Murphy
- Department of Forensic and Neurodevelopmental Sciences, and the Sackler Institute for Translational Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College, London SE5 8AF, UK
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10
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Abstract
In a double blind controlled study of 24 patients undergoing coronary artery bypass grafting, 12 received an infusion of prostacyclin at 20 ng/kg/min during cardiopulmonary bypass in an attempt to reduce the previously reported increased alveolar capillary membrane permeability that occurs postoperatively. Prostacyclin significantly reduced platelet activation but had no effect in reducing complement activation or transpulmonary neutrophil sequestration. Alveolar epithelial permeability as assessed by measuring the clearance of inhaled 99mTc-DTPA from lung to blood did not change postoperatively in either group. In order to fully evaluate pulmonary damage following cardiopulmonary bypass a marker for pulmonary endothelial damage may need to be used.
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Affiliation(s)
- DK Jones
- Department of Respiratory Physiology, Papworth Hosital
| | | | - D. Wheeldon
- Department of Cardiothoracic Surgery, Papworth Hospital
| | | | - D. Bethune
- Department of Anaesthesia Papworth Hospital
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Fuller S, Hamandi K, Jones DK, Gray WP. PREDICTING VISUAL FIELD DEFECTS FOLLOWING SELECTIVE TRANSSYLVIAN AMYGDALOHIPPOCAMPECTOMY. J Neurol Neurosurg Psychiatry 2015. [DOI: 10.1136/jnnp-2015-312379.57] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
IntroductionSurgery for refractory temporal lobe epilepsy can cause postoperative visual field defects (VFD). This study aimed to predict personalised risk of VFDs for patients undergoing selective transsylvian amygdalohippocampectomy.MethodsPreoperative reconstruction of the optic radiations (OR) using diffusion tensor-based tractography was completed on two patients. The ‘average resection model’ uses a template from postoperative structural scans of five patient scans to predict an average resection in the patient. The OR tractography was compared with the resection margins to determine fibre involvement. The ‘multiple individual comparison model’ compared individual postoperative scans with the preoperative tractography to determine risk of VFD.ResultsIn Patient 1 the average resection overlapped the OR, so an average resection would be expected to produce a VFD. In 3/5 postoperative scans the resection intersected with the OR, indicating that 60% of prior resections would have caused a defect. In Patient 2 no overlap between resection and OR was found in either model. Perimetry confirmed VFD in patient 1 but not in patient 2.DiscussionThis pilot study demonstrates that the risk of postoperative VFDs can be predicted. The two models provide qualitatively different form of quantitative risk which could inform the discussion between patient and clinician.
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12
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Santis S, Assaf Y, Evans CJ, Jones DK. Improved precision in CHARMED assessment of white matter through sampling scheme optimization and model parsimony testing. Magn Reson Med 2015; 71:661-71. [PMID: 23475834 DOI: 10.1002/mrm.24717] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
PURPOSE The composite hindered and restricted model of diffusion provides microstructural indices that are potentially more specific than those from diffusion tensor imaging. However, in comparison to diffusion tensor imaging, the acquisition time is longer, limiting clinical applications. Moreover, the model requires several parameters to be estimated whose confidence intervals can be large. Here, the composite hindered and restricted model of diffusion acquisition and data processing pipelines are optimized to extend the utility of this approach. METHODS A multishell sampling scheme was optimized using the electrostatic repulsion algorithm, combined with optimal ordering. The optimal protocol, using as few measurements as possible, was determined through leave-n-out analyses. Parsimonious model selection criteria were used to select between nested models, comprising up to three restricted compartments. The schemes were evaluated using both through Monte-Carlo simulations and in vivo data. RESULTS The optimization/model selection procedure resulted in increased accuracy and precision on the estimated parameters, allowing for a reduction in acquisition time and marked improvements in data quality. The final protocol provided whole brain coverage data in only 12 min. CONCLUSION Through careful optimization of the acquisition and analysis pipeline for the composite hindered and restricted model of diffusion, it is possible to reduce acquisition time for whole brain datasets to a time that is clinically applicable.
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Affiliation(s)
- S Santis
- CUBRIC School of Psychology, Cardiff University, Cardiff, UK; Neuroscience & Mental Health Research Institute, Cardiff University, Cardiff, UK
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13
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Drakesmith M, Caeyenberghs K, Dutt A, Lewis G, David AS, Jones DK. Overcoming the effects of false positives and threshold bias in graph theoretical analyses of neuroimaging data. Neuroimage 2015; 118:313-33. [PMID: 25982515 PMCID: PMC4558463 DOI: 10.1016/j.neuroimage.2015.05.011] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 03/12/2015] [Accepted: 05/05/2015] [Indexed: 11/17/2022] Open
Abstract
Graph theory (GT) is a powerful framework for quantifying topological features of neuroimaging-derived functional and structural networks. However, false positive (FP) connections arise frequently and influence the inferred topology of networks. Thresholding is often used to overcome this problem, but an appropriate threshold often relies on a priori assumptions, which will alter inferred network topologies. Four common network metrics (global efficiency, mean clustering coefficient, mean betweenness and smallworldness) were tested using a model tractography dataset. It was found that all four network metrics were significantly affected even by just one FP. Results also show that thresholding effectively dampens the impact of FPs, but at the expense of adding significant bias to network metrics. In a larger number (n=248) of tractography datasets, statistics were computed across random group permutations for a range of thresholds, revealing that statistics for network metrics varied significantly more than for non-network metrics (i.e., number of streamlines and number of edges). Varying degrees of network atrophy were introduced artificially to half the datasets, to test sensitivity to genuine group differences. For some network metrics, this atrophy was detected as significant (p<0.05, determined using permutation testing) only across a limited range of thresholds. We propose a multi-threshold permutation correction (MTPC) method, based on the cluster-enhanced permutation correction approach, to identify sustained significant effects across clusters of thresholds. This approach minimises requirements to determine a single threshold a priori. We demonstrate improved sensitivity of MTPC-corrected metrics to genuine group effects compared to an existing approach and demonstrate the use of MTPC on a previously published network analysis of tractography data derived from a clinical population. In conclusion, we show that there are large biases and instability induced by thresholding, making statistical comparisons of network metrics difficult. However, by testing for effects across multiple thresholds using MTPC, true group differences can be robustly identified.
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Affiliation(s)
- M Drakesmith
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Park Place, Cardiff CF10 3AT, UK; Neuroscience and Mental Health Research Institute (NMHRI), School of Medicine, Cardiff University, Maindy Road, Cardiff CF24 4HQ, UK.
| | - K Caeyenberghs
- School of Psychology, Faculty of Health Sciences, Australian Catholic University, 115 Victoria Parade, Melbourne, VIC 3065, Australia
| | - A Dutt
- Institute of Psychiatry, King's College London, 16 De Crespigny Park, London SE5 8AF, UK
| | - G Lewis
- Division of Psychiatry, Faculty of Brain Sciences, University College London, Charles Bell House, 67-73 Riding House Street, London W1W 7EJ, UK
| | - A S David
- Institute of Psychiatry, King's College London, 16 De Crespigny Park, London SE5 8AF, UK
| | - D K Jones
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Park Place, Cardiff CF10 3AT, UK; Neuroscience and Mental Health Research Institute (NMHRI), School of Medicine, Cardiff University, Maindy Road, Cardiff CF24 4HQ, UK
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14
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Bracht T, Doidge AN, Keedwell PA, Jones DK. Hedonic tone is associated with left supero-lateral medial forebrain bundle microstructure. Psychol Med 2015; 45:865-874. [PMID: 25124530 PMCID: PMC4413785 DOI: 10.1017/s0033291714001949] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Revised: 07/17/2014] [Accepted: 07/17/2014] [Indexed: 12/28/2022]
Abstract
BACKGROUND The medial forebrain bundle (MFB) is an important pathway of the reward system. Two branches have been described using diffusion magnetic resonance imaging (MRI)-based tractography: the infero-medial MFB (imMFB) and the supero-lateral MFB (slMFB). Previous studies point to white-matter microstructural alterations of the slMFB in major depressive disorder (MDD) during acute episodes. To extend this finding, this study investigates whether white-matter microstructure is also altered in MDD patients that are in remission. Further, we explore associations between diffusion MRI-based metrics of white-matter microstructure of imMFB, slMFB and hedonic tone, the ability to derive pleasure. METHOD Eighteen remitted depressed (RD) and 22 never depressed (ND) participants underwent high angular resolution diffusion-weighted imaging (HARDI) scans. To reconstruct the two pathways of the MFB (imMFB and slMFB) we used the damped Richardson-Lucy (dRL) algorithm. Mean fractional anisotropy (FA) was sampled along the tracts. RESULTS Mean FA of imMFB, slMFB and a comparison tract (the middle cerebellar peduncle) did not differ between ND and RD participants. Hedonic capacity correlated negatively with mean FA of the left slMFB, explaining 21% of the variance. CONCLUSIONS Diffusion MRI-based metrics of white-matter microstructure of the MFB in RD do not differ from ND. Hedonic capacity is associated with altered white-matter microstructure of the slMFB.
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Affiliation(s)
- T. Bracht
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, UK
- Neuroscience, Mental Health Research Institute, Cardiff University, Cardiff, UK
| | - A. N. Doidge
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, UK
- Neuroscience, Mental Health Research Institute, Cardiff University, Cardiff, UK
| | - P. A. Keedwell
- Neuroscience, Mental Health Research Institute, Cardiff University, Cardiff, UK
| | - D. K. Jones
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, UK
- Neuroscience, Mental Health Research Institute, Cardiff University, Cardiff, UK
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15
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Caeyenberghs K, Powell HWR, Thomas RH, Brindley L, Church C, Evans J, Muthukumaraswamy SD, Jones DK, Hamandi K. Hyperconnectivity in juvenile myoclonic epilepsy: a network analysis. Neuroimage Clin 2014; 7:98-104. [PMID: 25610771 PMCID: PMC4299970 DOI: 10.1016/j.nicl.2014.11.018] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 10/16/2014] [Accepted: 11/24/2014] [Indexed: 12/01/2022]
Abstract
Objective Juvenile myoclonic epilepsy (JME) is a common idiopathic (genetic) generalized epilepsy (IGE) syndrome characterized by impairments in executive and cognitive control, affecting independent living and psychosocial functioning. There is a growing consensus that JME is associated with abnormal function of diffuse brain networks, typically affecting frontal and fronto-thalamic areas. Methods Using diffusion MRI and a graph theoretical analysis, we examined bivariate (network-based statistic) and multivariate (global and local) properties of structural brain networks in patients with JME (N = 34) and matched controls. Neuropsychological assessment was performed in a subgroup of 14 patients. Results Neuropsychometry revealed impaired visual memory and naming in JME patients despite a normal full scale IQ (mean = 98.6). Both JME patients and controls exhibited a small world topology in their white matter networks, with no significant differences in the global multivariate network properties between the groups. The network-based statistic approach identified one subnetwork of hyperconnectivity in the JME group, involving primary motor, parietal and subcortical regions. Finally, there was a significant positive correlation in structural connectivity with cognitive task performance. Conclusions Our findings suggest that structural changes in JME patients are distributed at a network level, beyond the frontal lobes. The identified subnetwork includes key structures in spike wave generation, along with primary motor areas, which may contribute to myoclonic jerks. We conclude that analyzing the affected subnetworks may provide new insights into understanding seizure generation, as well as the cognitive deficits observed in JME patients. Subnetwork of hyperconnectivity in juvenile myoclonic epilepsy Hyperconnectivity in primary motor, parietal and subcortical regions Network-based statistics is a valuable tool for predicting functional cognitive deficits.
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Affiliation(s)
- K Caeyenberghs
- Department of Physical Therapy and Motor Rehabilitation, Faculty of Medicine and Health Sciences, University of Ghent, Ghent, Belgium ; Department of Movement and Sports Sciences, University of Ghent, Ghent, Belgium
| | - H W R Powell
- Department of Neurology, Morriston Hospital, Swansea, United Kingdom ; Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
| | - R H Thomas
- Department of Neurology, University Hospital of Wales, Alan Richens Welsh Epilepsy Centre, Cardiff, United Kingdom ; MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Hadyn Ellis Building, Cathays, United Kingdom
| | - L Brindley
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
| | - C Church
- Department of Neurology, University Hospital of Wales, Alan Richens Welsh Epilepsy Centre, Cardiff, United Kingdom
| | - J Evans
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
| | - S D Muthukumaraswamy
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
| | - D K Jones
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
| | - K Hamandi
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom ; Department of Neurology, University Hospital of Wales, Alan Richens Welsh Epilepsy Centre, Cardiff, United Kingdom
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Jones DK, Claydon TW, Ruben PC. Extracellular protons inhibit charge immobilization in the cardiac voltage-gated sodium channel. Biophys J 2014; 105:101-7. [PMID: 23823228 DOI: 10.1016/j.bpj.2013.04.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 04/10/2013] [Accepted: 04/12/2013] [Indexed: 11/25/2022] Open
Abstract
Low pH depolarizes the voltage-dependence of cardiac voltage-gated sodium (NaV1.5) channel activation and fast inactivation and destabilizes the fast-inactivated state. The molecular basis for these changes in protein behavior has not been reported. We hypothesized that changes in the kinetics of voltage sensor movement may destabilize the fast-inactivated state in NaV1.5. To test this idea, we recorded NaV1.5 gating currents in Xenopus oocytes using a cut-open voltage-clamp with extracellular solution titrated to either pH 7.4 or pH 6.0. Reducing extracellular pH significantly depolarized the voltage-dependence of both the QON/V and QOFF/V curves, and reduced the total charge immobilized during depolarization. We conclude that destabilized fast-inactivation and reduced charge immobilization in NaV1.5 at low pH are functionally related effects.
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Affiliation(s)
- D K Jones
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, British Columbia, Canada
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He BJ, Nolte G, Nagata K, Takano D, Yamazaki T, Fujimaki Y, Maeda T, Satoh Y, Heckers S, George MS, Lopes da Silva F, de Munck JC, Van Houdt PJ, Verdaasdonk RM, Ossenblok P, Mullinger K, Bowtell R, Bagshaw AP, Keeser D, Karch S, Segmiller F, Hantschk I, Berman A, Padberg F, Pogarell O, Scharnowski F, Karch S, Hümmer S, Keeser D, Paolini M, Kirsch V, Koller G, Rauchmann B, Kupka M, Blautzik J, Pogarell O, Razavi N, Jann K, Koenig T, Kottlow M, Hauf M, Strik W, Dierks T, Gotman J, Vulliemoz S, Lu Y, Zhang H, Yang L, Worrell G, He B, Gruber O, Piguet C, Hubl D, Homan P, Kindler J, Dierks T, Kim K, Steinhoff U, Wakai R, Koenig T, Kottlow M, Melie-García L, Mucci A, Volpe U, Prinster A, Salvatore M, Galderisi S, Linden DEJ, Brandeis D, Schroeder CE, Kayser C, Panzeri S, Kleinschmidt A, Ritter P, Walther S, Haueisen J, Lau S, Flemming L, Sonntag H, Maess B, Knösche TR, Lanfer B, Dannhauer M, Wolters CH, Stenroos M, Haueisen J, Wolters C, Aydin U, Lanfer B, Lew S, Lucka F, Ruthotto L, Vorwerk J, Wagner S, Ramon C, Guan C, Ang KK, Chua SG, Kuah WK, Phua KS, Chew E, Zhou H, Chuang KH, Ang BT, Wang C, Zhang H, Yang H, Chin ZY, Yu H, Pan Y, Collins L, Mainsah B, Colwell K, Morton K, Ryan D, Sellers E, Caves K, Throckmorton S, Kübler A, Holz EM, Zickler C, Sellers E, Ryan D, Brown K, Colwell K, Mainsah B, Caves K, Throckmorton S, Collins L, Wennberg R, Ahlfors SP, Grova C, Chowdhury R, Hedrich T, Heers M, Zelmann R, Hall JA, Lina JM, Kobayashi E, Oostendorp T, van Dam P, Oosterhof P, Linnenbank A, Coronel R, van Dessel P, de Bakker J, Rossion B, Jacques C, Witthoft N, Weiner KS, Foster BL, Miller KJ, Hermes D, Parvizi J, Grill-Spector K, Recanzone GH, Murray MM, Haynes JD, Richiardi J, Greicius M, De Lucia M, Müller KR, Formisano E, Smieskova R, Schmidt A, Bendfeldt K, Walter A, Riecher-Rössler A, Borgwardt S, Fusar-Poli P, Eliez S, Schmidt A, Sekihara K, Nagarajan SS, Schoffelen JM, Guggisberg AG, Nolte G, Balazs S, Kermanshahi K, Kiesenhofer W, Binder H, Rattay F, Antal A, Chaieb L, Paulus W, Bodis-Wollner I, Maurer K, Fein G, Camchong J, Johnstone J, Cardenas-Nicolson V, Fiederer LDJ, Lucka F, Yang S, Vorwerk J, Dümpelmann M, Cosandier-Rimélé D, Schulze-Bonhage A, Aertsen A, Speck O, Wolters CH, Ball T, Fuchs M, Wagner M, Kastner J, Tech R, Dinh C, Haueisen J, Baumgarten D, Hämäläinen MS, Lau S, Vogrin SJ, D'Souza W, Haueisen J, Cook MJ, Custo A, Van De Ville D, Vulliemoz S, Grouiller F, Michel CM, Malmivuo J, Aydin U, Vorwerk J, Küpper P, Heers M, Kugel H, Wellmer J, Kellinghaus C, Scherg M, Rampp S, Wolters C, Storti SF, Boscolo Galazzo I, Del Felice A, Pizzini FB, Arcaro C, Formaggio E, Mai R, Manganotti P, Koessler L, Vignal J, Cecchin T, Colnat-Coulbois S, Vespignani H, Ramantani G, Maillard L, Rektor I, Kuba R, Brázdil M, Chrastina J, Rektorova I, van Mierlo P, Carrette E, Strobbe G, Montes-Restrepo V, Vonck K, Vandenberghe S, Ahmed B, Brodely C, Carlson C, Kuzniecky R, Devinsky O, French J, Thesen T, Bénis D, David O, Lachaux JP, Seigneuret E, Krack P, Fraix V, Chabardès S, Bastin J, Jann K, Gee D, Kilroy E, Cannon T, Wang DJ, Hale JR, Mayhew SD, Przezdzik I, Arvanitis TN, Bagshaw AP, Plomp G, Quairiaux C, Astolfi L, Michel CM, Mayhew SD, Mullinger KJ, Bagshaw AP, Bowtell R, Francis ST, Schouten AC, Campfens SF, van der Kooij H, Koles Z, Lind J, Flor-Henry P, Wirth M, Haase CM, Villeneuve S, Vogel J, Jagust WJ, Kambeitz-Ilankovic L, Simon-Vermot L, Gesierich B, Duering M, Ewers M, Rektorova I, Krajcovicova L, Marecek R, Mikl M, Bracht T, Horn H, Strik W, Federspiel A, Schnell S, Höfle O, Stegmayer K, Wiest R, Dierks T, Müller TJ, Walther S, Surmeli T, Ertem A, Eralp E, Kos IH, Skrandies W, Flüggen S, Klein A, Britz J, Díaz Hernàndez L, Ro T, Michel CM, Lenartowicz A, Lau E, Rodriguez C, Cohen MS, Loo SK, Di Lorenzo G, Pagani M, Monaco L, Daverio A, Giannoudas I, La Porta P, Verardo AR, Niolu C, Fernandez I, Siracusano A, Flor-Henry P, Lind J, Koles Z, Bollmann S, Ghisleni C, O'Gorman R, Poil SS, Klaver P, Michels L, Martin E, Ball J, Eich-Höchli D, Brandeis D, Salisbury DF, Murphy TK, Butera CD, Mathalon DH, Fryer SL, Kiehl KA, Calhoun VC, Pearlson GD, Roach BJ, Ford JM, McGlashan TH, Woods SW, Volpe U, Merlotti E, Vignapiano A, Montefusco V, Plescia GM, Gallo O, Romano P, Mucci A, Galderisi S, Mingoia G, Langbein K, Dietzek M, Wagner G, Smesny, Scherpiet S, Maitra R, Gaser C, Sauer H, Nenadic I, Gonzalez Andino S, Grave de Peralta Menendez R, Grave de Peralta Menendez R, Sanchez Vives M, Rebollo B, Gonzalez Andino S, Frølich L, Andersen TS, Mørup M, Belfiore P, Gargiulo P, Ramon C, Vanhatalo S, Cho JH, Vorwerk J, Wolters CH, Knösche TR, Watanabe T, Kawabata Y, Ukegawa D, Kawabata S, Adachi Y, Sekihara K, Sekihara K, Nagarajan SS, Wagner S, Aydin U, Vorwerk J, Herrmann C, Burger M, Wolters C, Lucka F, Aydin U, Vorwerk J, Burger M, Wolters C, Bauer M, Trahms L, Sander T, Faber PL, Lehmann D, Gianotti LRR, Pascual-Marqui RD, Milz P, Kochi K, Kaneko S, Yamashita S, Yana K, Kalogianni K, Vardy AN, Schouten AC, van der Helm FCT, Sorrentino A, Luria G, Aramini R, Hunold A, Funke M, Eichardt R, Haueisen J, Gómez-Aguilar F, Vázquez-Olvera S, Cordova-Fraga T, Castro-López J, Hernández-Gonzalez MA, Solorio-Meza S, Sosa-Aquino M, Bernal-Alvarado JJ, Vargas-Luna M, Vorwerk J, Magyari L, Ludewig J, Oostenveld R, Wolters CH, Vorwerk J, Engwer C, Ludewig J, Wolters C, Sato K, Nishibe T, Furuya M, Yamashiro K, Yana K, Ono T, Puthanmadam Subramaniyam N, Hyttinen J, Lau S, Güllmar D, Flemming L, Haueisen J, Sonntag H, Vorwerk J, Wolters CH, Grasedyck L, Haueisen J, Maeß B, Freitag S, Graichen U, Fiedler P, Strohmeier D, Haueisen J, Stenroos M, Hauk O, Grigutsch M, Felber M, Maess B, Herrmann B, Strobbe G, van Mierlo P, Vandenberghe S, Strobbe G, Cárdenas-Peña D, Montes-Restrepo V, van Mierlo P, Castellanos-Dominguez G, Vandenberghe S, Lanfer B, Paul-Jordanov I, Scherg M, Wolters CH, Ito Y, Sato D, Kamada K, Kobayashi T, Dalal SS, Rampp S, Willomitzer F, Arold O, Fouladi-Movahed S, Häusler G, Stefan H, Ettl S, Zhang S, Zhang Y, Li H, Kong X, Montes-Restrepo V, Strobbe G, van Mierlo P, Vandenberghe S, Wong DDE, Bidet-Caulet A, Knight RT, Crone NE, Dalal SS, Birot G, Spinelli L, Vulliémoz S, Seeck M, Michel CM, Emory H, Wells C, Mizrahi N, Vogrin SJ, Lau S, Cook MJ, Karahanoglu FI, Grouiller F, Caballero-Gaudes C, Seeck M, Vulliemoz S, Van De Ville D, Spinelli L, Megevand P, Genetti M, Schaller K, Michel C, Vulliemoz S, Seeck M, Genetti M, Tyrand R, Grouiller F, Vulliemoz S, Spinelli L, Seeck M, Schaller K, Michel CM, Grouiller F, Heinzer S, Delattre B, Lazeyras F, Spinelli L, Pittau F, Seeck M, Ratib O, Vargas M, Garibotto V, Vulliemoz S, Vogrin SJ, Bailey CA, Kean M, Warren AE, Davidson A, Seal M, Harvey AS, Archer JS, Papadopoulou M, Leite M, van Mierlo P, Vonck K, Boon P, Friston K, Marinazzo D, Ramon C, Holmes M, Koessler L, Rikir E, Gavaret M, Bartolomei F, Vignal JP, Vespignani H, Maillard L, Centeno M, Perani S, Pier K, Lemieux L, Clayden J, Clark C, Pressler R, Cross H, Carmichael DW, Spring A, Bessemer R, Pittman D, Aghakhani Y, Federico P, Pittau F, Grouiller F, Vulliémoz S, Gotman J, Badier JM, Bénar CG, Bartolomei F, Cruto C, Chauvel P, Gavaret M, Brodbeck V, van Leeuwen T, Tagliazzuchi E, Melloni L, Laufs H, Griskova-Bulanova I, Dapsys K, Klein C, Hänggi J, Jäncke L, Ehinger BV, Fischer P, Gert AL, Kaufhold L, Weber F, Marchante Fernandez M, Pipa G, König P, Sekihara K, Hiyama E, Koga R, Iannilli E, Michel CM, Bartmuss AL, Gupta N, Hummel T, Boecker R, Holz N, Buchmann AF, Blomeyer D, Plichta MM, Wolf I, Baumeister S, Meyer-Lindenberg A, Banaschewski T, Brandeis D, Laucht M, Natahara S, Ueno M, Kobayashi T, Kottlow M, Bänninger A, Koenig T, Schwab S, Koenig T, Federspiel A, Dierks T, Jann K, Natsukawa H, Kobayashi T, Tüshaus L, Koenig T, Kottlow M, Achermann P, Wilson RS, Mayhew SD, Assecondi S, Arvanitis TN, Bagshaw AP, Darque A, Rihs TA, Grouiller F, Lazeyras F, Ha-Vinh Leuchter R, Caballero C, Michel CM, Hüppi PS, Hauser TU, Hunt LT, Iannaccone R, Stämpfli P, Brandeis D, Dolan RJ, Walitza S, Brem S, Graichen U, Eichardt R, Fiedler P, Strohmeier D, Freitag S, Zanow F, Haueisen J, Lordier L, Grouiller F, Van de Ville D, Sancho Rossignol A, Cordero I, Lazeyras F, Ansermet F, Hüppi P, Schläpfer A, Rubia K, Brandeis D, Di Lorenzo G, Pagani M, Monaco L, Daverio A, Giannoudas I, Verardo AR, La Porta P, Niolu C, Fernandez I, Siracusano A, Tamura K, Karube C, Mizuba T, Matsufuji M, Takashima S, Iramina K, Assecondi S, Ostwald D, Bagshaw AP, Marecek R, Brazdil M, Lamos M, Slavícek T, Marecek R, Jan J, Meier NM, Perrig W, Koenig T, Minami T, Noritake Y, Nakauchi S, Azuma K, Minami T, Nakauchi S, Rodriguez C, Lenartowicz A, Cohen MS, Rodriguez C, Lenartowicz A, Cohen MS, Iramina K, Kinoshita H, Tamura K, Karube C, Kaneko M, Ide J, Noguchi Y, Cohen MS, Douglas PK, Rodriguez CM, Xia HJ, Zimmerman EM, Konopka CJ, Epstein PS, Konopka LM, Giezendanner S, Fisler M, Soravia L, Andreotti J, Wiest R, Dierks T, Federspiel A, Razavi N, Federspiel A, Dierks T, Hauf M, Jann K, Kamada K, Sato D, Ito Y, Okano K, Mizutani N, Kobayashi T, Thelen A, Murray M, Pastena L, Formaggio E, Storti SF, Faralli F, Melucci M, Gagliardi R, Ricciardi L, Ruffino G, Coito A, Macku P, Tyrand R, Astolfi L, He B, Wiest R, Seeck M, Michel C, Plomp G, Vulliemoz S, Fischmeister FPS, Glaser J, Schöpf V, Bauer H, Beisteiner R, Deligianni F, Centeno M, Carmichael DW, Clayden J, Mingoia G, Langbein K, Dietzek M, Wagner G, Smesny S, Scherpiet S, Maitra R, Gaser C, Sauer H, Nenadic I, Dürschmid S, Zaehle T, Pannek H, Chang HF, Voges J, Rieger J, Knight RT, Heinze HJ, Hinrichs H, Tsatsishvili V, Cong F, Puoliväli T, Alluri V, Toiviainen P, Nandi AK, Brattico E, Ristaniemi T, Grieder M, Crinelli RM, Jann K, Federspiel A, Wirth M, Koenig T, Stein M, Wahlund LO, Dierks T, Atsumori H, Yamaguchi R, Okano Y, Sato H, Funane T, Sakamoto K, Kiguchi M, Tränkner A, Schindler S, Schmidt F, Strauß M, Trampel R, Hegerl U, Turner R, Geyer S, Schönknecht P, Kebets V, van Assche M, Goldstein R, van der Meulen M, Vuilleumier P, Richiardi J, Van De Ville D, Assal F, Wozniak-Kwasniewska A, Szekely D, Harquel S, Bougerol T, David O, Bracht T, Jones DK, Horn H, Müller TJ, Walther S, Sos P, Klirova M, Novak T, Brunovsky M, Horacek J, Bares M, Hoschl C C, Fellhauer I, Zöllner FG, Schröder J, Kong L, Essig M, Schad LR, Arrubla J, Neuner I, Hahn D, Boers F, Shah NJ, Neuner I, Arrubla J, Hahn D, Boers F, Jon Shah N, Suriya Prakash M, Sharma R, Kawaguchi H, Kobayashi T, Fiedler P, Griebel S, Biller S, Fonseca C, Vaz F, Zentner L, Zanow F, Haueisen J, Rochas V, Rihs T, Thut G, Rosenberg N, Landis T, Michel C, Moliadze V, Schmanke T, Lyzhko E, Bassüner S, Freitag C, Siniatchkin M, Thézé R, Guggisberg AG, Nahum L, Schnider A, Meier L, Friedrich H, Jann K, Landis B, Wiest R, Federspiel A, Strik W, Dierks T, Witte M, Kober SE, Neuper C, Wood G, König R, Matysiak A, Kordecki W, Sieluzycki C, Zacharias N, Heil P, Wyss C, Boers F, Arrubla J, Dammers J, Kawohl W, Neuner I, Shah NJ, Braboszcz C, Cahn RB, Levy J, Fernandez M, Delorme A, Rosas-Martinez L, Milne E, Zheng Y, Urakami Y, Kawamura K, Washizawa Y, Hiyoshi K, Cichocki A, Giroud N, Dellwo V, Meyer M, Rufener KS, Liem F, Dellwo V, Meyer M, Jones-Rounds JD, Raizada R, Staljanssens W, Strobbe G, van Mierlo P, Van Holen R, Vandenberghe S, Pefkou M, Becker R, Michel C, Hervais-Adelman A, He W, Brock J, Johnson B, Ohla K, Hitz K, Heekeren K, Obermann C, Huber T, Juckel G, Kawohl W, Gabriel D, Comte A, Henriques J, Magnin E, Grigoryeva L, Ortega JP, Haffen E, Moulin T, Pazart L, Aubry R, Kukleta M, Baris Turak B, Louvel J, Crespo-Garcia M, Cantero JL, Atienza M, Connell S, Kilborn K, Damborská A, Brázdil M, Rektor I, Kukleta M, Koberda JL, Bienkiewicz A, Koberda I, Koberda P, Moses A, Tomescu M, Rihs T, Britz J, Custo A, Grouiller F, Schneider M, Debbané M, Eliez S, Michel C, Wang GY, Kydd R, Wouldes TA, Jensen M, Russell BR, Dissanayaka N, Au T, Angwin A, O'Sullivan J, Byrne G, Silburn P, Marsh R, Mellic G, Copland D, Bänninger A, Kottlow M, Díaz Hernàndez L, Koenig T, Díaz Hernàndez L, Bänninger A, Koenig T, Hauser TU, Iannaccone R, Mathys C, Ball J, Drechsler R, Brandeis D, Walitza S, Brem S, Boeijinga PH, Pang EW, Valica T, Macdonald MJ, Oh A, Lerch JP, Anagnostou E, Di Lorenzo G, Pagani M, Monaco L, Daverio A, Verardo AR, Giannoudas I, La Porta P, Niolu C, Fernandez I, Siracusano A, Shimada T, Matsuda Y, Monkawa A, Monkawa T, Hashimoto R, Watanabe K, Kawasaki Y, Matsuda Y, Shimada T, Monkawa T, Monkawa A, Watanabe K, Kawasaki Y, Stegmayer K, Horn H, Federspiel A, Razavi N, Bracht T, Laimböck K, Strik W, Dierks T, Wiest R, Müller TJ, Walther S, Koorenhof LJ, Swithenby SJ, Martins-Mourao A, Rihs TA, Tomescu M, Song KW, Custo A, Knebel JF, Murray M, Eliez S, Michel CM, Volpe U, Merlotti E, Vignapiano A, Montefusco V, Plescia GM, Gallo O, Romano P, Mucci A, Galderisi S, Laimboeck K, Jann K, Walther S, Federspiel A, Wiest R, Strik W, Horn H. Abstracts of Presentations at the International Conference on Basic and Clinical Multimodal Imaging (BaCI), a Joint Conference of the International Society for Neuroimaging in Psychiatry (ISNIP), the International Society for Functional Source Imaging (ISFSI), the International Society for Bioelectromagnetism (ISBEM), the International Society for Brain Electromagnetic Topography (ISBET), and the EEG and Clinical Neuroscience Society (ECNS), in Geneva, Switzerland, September 5-8, 2013. Clin EEG Neurosci 2013; 44:1550059413507209. [PMID: 24368763 DOI: 10.1177/1550059413507209] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- B J He
- National Institutes of Health, Bethesda, MD, USA
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Parker GD, Marshall D, Rosin PL, Drage N, Richmond S, Jones DK. A pitfall in the reconstruction of fibre ODFs using spherical deconvolution of diffusion MRI data. Neuroimage 2012; 65:433-48. [PMID: 23085109 PMCID: PMC3580290 DOI: 10.1016/j.neuroimage.2012.10.022] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2011] [Revised: 10/12/2012] [Accepted: 10/13/2012] [Indexed: 11/30/2022] Open
Abstract
Diffusion weighted (DW) MRI facilitates non-invasive quantification of tissue microstructure and, in combination with appropriate signal processing, three-dimensional estimates of fibrous orientation. In recent years, attention has shifted from the diffusion tensor model, which assumes a unimodal Gaussian diffusion displacement profile to recover fibre orientation (with various well-documented limitations), towards more complex high angular resolution diffusion imaging (HARDI) analysis techniques. Spherical deconvolution (SD) approaches assume that the fibre orientation density function (fODF) within a voxel can be obtained by deconvolving a ‘common’ single fibre response function from the observed set of DW signals. In practice, this common response function is not known a priori and thus an estimated fibre response must be used. Here the establishment of this single-fibre response function is referred to as ‘calibration’. This work examines the vulnerability of two different SD approaches to inappropriate response function calibration: (1) constrained spherical harmonic deconvolution (CSHD)—a technique that exploits spherical harmonic basis sets and (2) damped Richardson–Lucy (dRL) deconvolution—a technique based on the standard Richardson–Lucy deconvolution. Through simulations, the impact of a discrepancy between the calibrated diffusion profiles and the observed (‘Target’) DW-signals in both single and crossing-fibre configurations was investigated. The results show that CSHD produces spurious fODF peaks (consistent with well known ringing artefacts) as the discrepancy between calibration and target response increases, while dRL demonstrates a lower over-all sensitivity to miscalibration (with a calibration response function for a highly anisotropic fibre being optimal). However, dRL demonstrates a reduced ability to resolve low anisotropy crossing-fibres compared to CSHD. It is concluded that the range and spatial-distribution of expected single-fibre anisotropies within an image must be carefully considered to ensure selection of the appropriate algorithm, parameters and calibration. Failure to choose the calibration response function carefully may severely impact the quality of any resultant tractography.
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Affiliation(s)
- G D Parker
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Roath, Cardiff, UK.
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Tsermentseli S, Dell'Acqua F, Landau S, Williams SCR, Jones DK, Leigh PN, Catani M, Goldstein LH. P20 Frontal white matter connections and cognitive change in amyotrophic lateral sclerosis: a DTI-tractography study. J Neurol Psychiatry 2012. [DOI: 10.1136/jnnp-2012-303538.37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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De Santis S, Evans CJ, Jones DK. RAPID: A routine assurance pipeline for imaging of diffusion. Magn Reson Med 2012; 70:490-6. [DOI: 10.1002/mrm.24465] [Citation(s) in RCA: 7] [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] [Received: 05/02/2012] [Revised: 07/02/2012] [Accepted: 07/26/2012] [Indexed: 11/11/2022]
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Blain CRV, Brunton S, Williams VC, Leemans A, Turner MR, Andersen PM, Catani M, Stanton BR, Ganesalingham J, Jones DK, Williams SCR, Leigh PN, Simmons A. Differential corticospinal tract degeneration in homozygous 'D90A' SOD-1 ALS and sporadic ALS. J Neurol Neurosurg Psychiatry 2011; 82:843-9. [PMID: 21515558 PMCID: PMC3134064 DOI: 10.1136/jnnp.2010.236018] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND The homogeneous genotype and stereotyped phenotype of a unique familial form of amyotrophic lateral sclerosis (ALS) (patients homozygous for aspartate-to-alanine mutations in codon 90 (homD90A) superoxide dismutase 1) provides an ideal model for studying genotype/phenotype interactions and pathological features compared with heterogeneous apparently sporadic ALS. The authors aimed to use diffusion tensor tractography to quantify and compare changes in the intracerebral corticospinal tracts of patients with both forms of ALS, building on previous work using whole-brain voxelwise group analysis. METHOD 21 sporadic ALS patients, seven homD90A patients and 20 healthy controls underwent 1.5 T diffusion tensor MRI. Patients were assessed using 'upper motor neuron burden,' El Escorial and ALSFR-R scales. The intracranial corticospinal tract was assessed using diffusion tensor tractography measures of fractional anisotropy (FA), mean diffusivity, and radial and axial diffusivity obtained from its entire length. RESULTS Corticospinal tract FA was reduced in sporadic ALS patients compared with both homD90A ALS patients and controls. The diffusion measures in sporadic ALS patients were consistent with anterograde (Wallerian) degeneration of the corticospinal tracts. In sporadic ALS, corticospinal tract FA was related to clinical measures. Despite a similar degree of clinical upper motor neuron dysfunction and disability in homD90A ALS patients compared with sporadic ALS, there were no abnormalities in corticospinal tract diffusion measures compared with controls. CONCLUSIONS Diffusion tensor tractography has shown axonal degeneration within the intracerebral portion of the corticospinal tract in sporadic ALS patients, but not those with a homogeneous form of familial ALS. This suggests significant genotypic influences on the phenotype of ALS and may provide clues to slower progression of disease in homD90A patients.
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Affiliation(s)
- C R V Blain
- Department of Clinical Neuroscience, King’s College London, Institute of Psychiatry, London, UK
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Singh KD, Muthukumaraswamy SD, Jones DK, Swettenham JB, Edden RAE. The level of GABAergic inhibition predicts peak gamma frequency and fMRI amplitude in humans. Neuroimage 2009. [DOI: 10.1016/s1053-8119(09)71401-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Blain CRV, Barker GJ, Jarosz JM, Coyle NA, Landau S, Brown RG, Chaudhuri KR, Simmons A, Jones DK, Williams SCR, Leigh PN. Measuring brain stem and cerebellar damage in parkinsonian syndromes using diffusion tensor MRI. Neurology 2007; 67:2199-205. [PMID: 17190944 DOI: 10.1212/01.wnl.0000249307.59950.f8] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.2] [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: 11/15/2022] Open
Abstract
OBJECTIVE To use diffusion tensor MRI to quantify and compare degeneration of the pons and cerebellar peduncles in multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and Parkinson disease (PD) and to relate changes in diffusion measures to clinical features and localized atrophy. METHODS We used a region-of-interest approach to measure changes in fractional anisotropy and mean diffusivity in the middle cerebellar peduncles, decussation of the superior cerebellar peduncles, and pons in 17 patients with MSA, 17 with PSP, 12 with PD, and 12 healthy volunteers. We also evaluated atrophy of the cerebellar peduncles and pons on T2-weighted magnetic resonance images in patients with MSA and PSP. RESULTS In MSA, fractional anisotropy was markedly reduced in the middle cerebellar peduncles, and mean diffusivity increased both here and in the pons compared with other groups, whereas in PSP, mean diffusivity was strikingly increased in the decussation of superior cerebellar peduncles. Cerebellar ataxia was related to mean diffusivity in the middle cerebellar peduncles (r = 0.71, p = 0.001) and pons (r = 0.60, p = 0.01) in MSA. Diffusion measures were related to localized atrophy in both MSA and PSP. CONCLUSIONS Diffusion tensor MRI can be used to quantify neurodegenerative processes in different brain stem and cerebellar structures in multiple system atrophy and progressive supranuclear palsy during life, and may have diagnostic value. Larger studies of early, undifferentiated parkinsonian syndromes are indicated to provide estimates of the relative diagnostic value of diffusion measures, atrophy measures, and visual assessment of scans.
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Affiliation(s)
- C R V Blain
- King's College London, Institute of Psychiatry, MRC Centre for Neurodegeneration, Department of Clinical Neuroscience, London, UK
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O'Sullivan M, Morris RG, Huckstep B, Jones DK, Williams SCR, Markus HS. Diffusion tensor MRI correlates with executive dysfunction in patients with ischaemic leukoaraiosis. J Neurol Neurosurg Psychiatry 2004; 75:441-7. [PMID: 14966162 PMCID: PMC1738975 DOI: 10.1136/jnnp.2003.014910] [Citation(s) in RCA: 257] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Cerebral small vessel disease is a common cause of vascular dementia. Both discrete lacunar infarcts and more diffuse ischaemic changes, seen as confluent high signal (leukoaraiosis) on T2 weighted magnetic resonance imaging (MRI), occur. However, there is a weak correlation between T2 lesion load and cognitive impairment. Diffusion tensor MRI (DTI) is a new technique that may provide a better index of white matter damage. OBJECTIVES To determine whether DTI measures are correlated more strongly with cognitive performance than lesion load on T2 weighted images, and whether these correlations are independent of conventional MRI parameters. METHODS 36 patients with ischaemic leukoaraiosis (leukoaraiosis plus a previous lacunar stroke) and 19 healthy volunteers underwent DTI, conventional MRI, and neuropsychological assessment. RESULTS On DTI, diffusivity was increased both within lesions and in normal appearing white matter. Mean diffusivity of normal appearing white matter correlated with full scale IQ (r = -0.46, p = 0.009) and tests of executive function. These correlations remained significant after controlling for age, sex, brain volume, and T1/T2 lesion volumes. No significant correlation was identified between T2 lesion load and IQ or neuropsychological scores. Of conventional measures, brain volume correlated best with cognitive function. CONCLUSIONS Diffusion tensor measurements correlate better with cognition than conventional MRI measures. They may be useful in monitoring disease progression and as a surrogate marker for treatment trials. The findings support the role of white matter damage and disruption of white matter connections in the pathogenesis of cognitive impairment in cerebral small vessel disease.
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Affiliation(s)
- M O'Sullivan
- Clinical Neuroscience, St George's Hospital Medical School, London SW17, UK
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O'Sullivan M, Summers PE, Jones DK, Jarosz JM, Williams SC, Markus HS. Normal-appearing white matter in ischemic leukoaraiosis: a diffusion tensor MRI study. Neurology 2001; 57:2307-10. [PMID: 11756617 DOI: 10.1212/wnl.57.12.2307] [Citation(s) in RCA: 177] [Impact Index Per Article: 7.7] [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: 11/15/2022] Open
Abstract
Ischemic leukoaraiosis is a consistent concomitant of vascular dementia. Conventional MRI provides little information about underlying white matter tract disruption and correlates poorly with cognitive dysfunction. Diffusion tensor MRI may provide better markers of tract integrity. Changes in the normal-appearing white matter were demonstrated in 30 patients with ischemic leukoaraiosis compared with 17 age-matched control subjects. These changes correlated with executive dysfunction assessed by the Wisconsin Card Sorting Test.
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Affiliation(s)
- M O'Sullivan
- Division of Clinical Neuroscience, Institute of Psychiatry, London, UK.
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Rose SE, Chalk JB, Griffin MP, Janke AL, Chen F, McLachan GJ, Peel D, Zelaya FO, Markus HS, Jones DK, Simmons A, O'Sullivan M, Jarosz JM, Strugnell W, Doddrell DM, Semple J. MRI based diffusion and perfusion predictive model to estimate stroke evolution. Magn Reson Imaging 2001; 19:1043-53. [PMID: 11711228 DOI: 10.1016/s0730-725x(01)00435-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In this study we present a novel automated strategy for predicting infarct evolution, based on MR diffusion and perfusion images acquired in the acute stage of stroke. The validity of this methodology was tested on novel patient data including data acquired from an independent stroke clinic. Regions-of-interest (ROIs) defining the initial diffusion lesion and tissue with abnormal hemodynamic function as defined by the mean transit time (MTT) abnormality were automatically extracted from DWI/PI maps. Quantitative measures of cerebral blood flow (CBF) and volume (CBV) along with ratio measures defined relative to the contralateral hemisphere (r(a)CBF and r(a)CBV) were calculated for the MTT ROIs. A parametric normal classifier algorithm incorporating these measures was used to predict infarct growth. The mean r(a)CBF and r(a)CBV values for eventually infarcted MTT tissue were 0.70 +/- 0.19 and 1.20 +/- 0.36. For recovered tissue the mean values were 0.99 +/- 0.25 and 1.87 +/- 0.71, respectively. There was a significant difference between these two regions for both measures (p < 0.003 and p < 0.001, respectively). Mean absolute measures of CBF (ml/100g/min) and CBV (ml/100g) for the total infarcted territory were 33.9 +/- 9.7 and 4.2 +/- 1.9. For recovered MTT tissue, the mean values were 41.5 +/- 7.2 and 5.3 +/- 1.2, respectively. A significant difference was also found for these regions (p < 0.009 and p < 0.036, respectively). The mean measures of sensitivity, specificity, positive and negative predictive values for modeling infarct evolution for the validation patient data were 0.72 +/- 0.05, 0.97 +/- 0.02, 0.68 +/- 0.07 and 0.97 +/- 0.02. We propose that this automated strategy may allow possible guided therapeutic intervention to stroke patients and evaluation of efficacy of novel stroke compounds in clinical drug trials.
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Affiliation(s)
- S E Rose
- Centre For Magnetic Resonance, University of Queensland, Brisbane, Queensland 4072, Australia.
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O'Sullivan M, Jones DK, Summers PE, Morris RG, Williams SC, Markus HS. Evidence for cortical "disconnection" as a mechanism of age-related cognitive decline. Neurology 2001; 57:632-8. [PMID: 11524471 DOI: 10.1212/wnl.57.4.632] [Citation(s) in RCA: 556] [Impact Index Per Article: 24.2] [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: 11/15/2022] Open
Abstract
BACKGROUND Normal aging is accompanied by a decline of cognitive abilities, and executive skills may be affected selectively, but the underlying mechanisms remain obscure and preventive strategies are lacking. It has been suggested that cortical "disconnection" due to the loss of white matter fibers may play an important role. But, to date, there has been no direct demonstration of structural disconnection in humans in vivo. METHODS The authors used diffusion tensor MRI to look for evidence of ultrastructural changes in cerebral white matter in a group of 20 elderly volunteers with normal conventional MRI scans, and a group of 10 younger controls. The older group also underwent neuropsychological assessment. RESULTS Diffusional anisotropy, a marker of white matter tract integrity, was reduced in the white matter of older subjects and fell linearly with increasing age in the older group. Mean diffusivity was higher in the older group and increased with age. These changes were maximal in anterior white matter. In the older group, anterior mean diffusivity correlated with executive function assessed by the Trail Making Test. CONCLUSIONS These findings provide direct evidence that white matter tract disruption occurs in normal aging and would be consistent with the cortical disconnection hypothesis of age-related cognitive decline. Maximal changes in anterior white matter provide a plausible structural basis for selective loss of executive functions. In addition to providing new information about the biological basis of cognitive abilities, diffusion tensor MRI may be a sensitive tool for assessing interventions aimed at preventing cognitive decline.
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Affiliation(s)
- M O'Sullivan
- Division of Clinical Neuroscience, St. George's Hospital Medical School, London, United Kingdom.
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Abstract
OBJECTIVE To evaluate prospectively the efficacy of extracorporeal shock wave therapy (ESWT) as a conservative treatment for Peyronie's disease. PATIENTS AND METHODS After obtaining ethical committee approval, 37 patients with Peyronie's disease were treated using ESWT. Before treatment the degree of angulation was assessed by artificially inducing an erection with a vacuum device. The severity of pain on erection was assessed using a visual analogue scale (0-5). Each patient was treated with a minimum of three sessions of ESWT (3000 shock waves at an energy density of 0.11-0.17 mJ/mm2) at 3-week intervals. The results were analysed using the Wilcoxon signed-rank test. RESULTS Of the 37 patients, 34 completed the protocol; the mean (range) duration of the disease was 19.43 (4-60) months and the mean follow-up 7.5 (5-11) months. Almost half (47%) of the patients reported an improvement in angulation, with a mean reduction of 29.3 degrees (10 degrees -60 degrees ) (P < 0.001); 12 of the 20 (60%) patients with pain on erection reported immediate relief, the mean reduction being 2.3 (1-4) on the visual analogue scale (P < 0.001). There was only minimal bruising at the site of treatment and no major side-effects were reported. CONCLUSION ESWT is an effective and safe treatment for Peyronie's disease; the long-term follow-up and results are awaited.
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Affiliation(s)
- J Husain
- Department of Urology, Stepping Hill Hospital, Stockport, UK
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Jones DK, Dardis R, Ervine M, Horsfield MA, Jeffree M, Simmons A, Jarosz J, Strong AJ. Cluster analysis of diffusion tensor magnetic resonance images in human head injury. Neurosurgery 2000; 47:306-13; discussion 313-4. [PMID: 10942003 DOI: 10.1097/00006123-200008000-00008] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
OBJECTIVE Issues surrounding the nature of the edema associated with traumatic brain injury in humans, and its evolution in the acute phase, remain unresolved. This study aimed to characterize the topographical nature of the pathophysiological changes in human traumatic brain injury with diffusion tensor magnetic resonance imaging. METHODS Multislice diffusion-weighted magnetic resonance imaging data were acquired from five patients undergoing elective ventilation for management of traumatic focal contusion or hematomas. The diffusion tensor and the T2-weighted intensity were then computed for every voxel in the image data set for each patient. The topographical distribution of abnormalities in the trace of the diffusion tensor and T2-weighted images were characterized by cluster analysis. RESULTS In four patients with technically satisfactory data, a narrow band of tissue was observed in the periphery of focal lesions, which was characterized by selective reduction in the trace of the diffusion tensor, without any associated increase in the T2-weighted signal intensity. CONCLUSION This change is interpreted as indicating either a partial redistribution of water from the extra- to intracellular compartment, or a reduction in the diffusivity of water in the intracellular or cytosolic environment. These diffusion and T2-weighted characteristics are also found in early ischemic change, hence, such regions may represent potentially salvageable tissue at risk of permanent damage. The study illustrates the advantage of using information contained within the diffusion tensor in addition to more conventional imaging sequences.
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Affiliation(s)
- D K Jones
- Section of Old Age Psychiatry, Institute of Psychiatry, King's College London, De Crespigny Park, England
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Cooper RA, Jones DK, Fitzgerald S, Boninger ML, Albright SJ. Analysis of position and isometric joysticks for powered wheelchair driving. IEEE Trans Biomed Eng 2000; 47:902-10. [PMID: 10916261 DOI: 10.1109/10.846684] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The control interface is one of the most critical components of the electric-powered wheelchair (EPW). The control interface must accommodate the user's limitations and maximize the user's abilities. This study extended Fitts' Law for target-acquisition to a continuously updated target. The extended Fitts' Law was used to examine EPW driving with a standard position sensing joystick and a prototype isometric joystick (IJ). The extended Fitts' Law provides insight into the difficulty of performing target-acquisition tasks with an EPW. The test results showed significant differences (p < 0.05) among the two types of joysticks for selected measures of information processing capacity, movement time, root-mean-square-error, and average velocity while performing turning maneuvers. The mean values indicate that the IJ may provide superior turning performance.
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Affiliation(s)
- R A Cooper
- Department of Rehabilitation Science, University of Pittsburgh, PA 15206, USA. rcooper+@pitt.edu
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Abstract
A strategic assessment of the contributions of two active-site hydrogen bonds in the binding of nicotinate to recombinant ferric soybean leghaemoglobin a (rLb) was carried out by mutagenic replacement of the hydrogen-bonding residues (H61A and Y30A variants) and by complementary chemical substitution of the carboxylate functionality on the nicotinate ligand. Dissociation constants, Kd (pH 5.5, mu = 0.10 M, 25.0 +/- 0.1 degrees C), for binding of nicotinate to ferric rLb, H61A and Y30A were 1.4 +/- 0.3 microM, 19 +/- 1 microM and 11 +/- 1 microM, respectively; dissociation constants for binding of nicotinamide were, respectively, 38 +/- 1 mM, 50 +/- 2 mM and 12 +/- 1 mM, and for binding of pyridine were 260 +/- 50 microM, 4.5 +/- 0.5 microM and 66 +/- 8 microM, respectively. Binding of cyanide and azide to the H61A and Y30A variants was unaffected by the mutations. The pH-dependence of nicotinate binding for rLb and Y30A was consistent with a single titration process (pKa values 6.9 +/- 0.1 and 6.7 +/- 0.2, respectively); binding of nicotinate to H61A was independent of pH. Reduction potentials for the rLb and rLb-nicotinate derivatives were 29 +/- 2 mV (pH 5.40, 25.0 degrees C, mu = 0.10 M) and - 65 +/- 2 mV (pH 5.42, 25.0 degrees C, mu = 0.10 M), respectively. The experiments provide a quantitative assessment of the role of individual hydrogen bonds in the binding process, together with a definitive determination of the pKa of His61 and unambiguous evidence that titration of His61 controls binding in the neutral to alkaline region.
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Affiliation(s)
- N Patel
- Department of Chemistry, University of Leicester, UK
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Cinà CS, Irvine KP, Jones DK. A modified technique of atriofemoral bypass for visceral and distal aortic perfusion in thoracoabdominal aortic surgery. Ann Vasc Surg 1999; 13:560-5. [PMID: 10541606 DOI: 10.1007/s100169900298] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Modified atriofemoral bypass (AFB) was used for repair of thoracoabdominal aortic aneurysms (TAAA). The primary circuit consisted of a centrifugal pump and heat exchanger to perfuse and warm the systemic circulation. A parallel secondary circuit with a second heat exchanger perfused the viscera with cold blood. A progressive sequential cross-clamping technique was used. This technique offers theoretical hemodynamic and metabolic advantages and may prove to be useful in preventing ischemic and reperfusion injury to the spinal cord and kidneys.
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Affiliation(s)
- C S Cinà
- Division of Vascular Surgery, Department of Surgery, Hamilton Health Sciences Corporation, McMaster University, Hamilton, Ontario, Canada
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34
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Ellis CM, Simmons A, Jones DK, Bland J, Dawson JM, Horsfield MA, Williams SC, Leigh PN. Diffusion tensor MRI assesses corticospinal tract damage in ALS. Neurology 1999; 53:1051-8. [PMID: 10496265 DOI: 10.1212/wnl.53.5.1051] [Citation(s) in RCA: 316] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND A number of neurophysiologic and neuroimaging techniques have been evaluated in the research setting to assess upper motor neuron (UMN) damage in ALS. Changes in tissue structure in the CNS modify the diffusional behavior of water molecules, which can be detected by diffusion tensor MRI. OBJECTIVES To explore the hypothesis that degeneration of the motor fibers in ALS would be reflected by changes in the diffusion characteristics of the white matter fibers in the posterior limb of the internal capsule and that these changes could be detected by diffusion tensor MRI. METHODS We studied 22 patients with El Escorial definite, probable, or possible ALS-11 with limb onset (mean age 54.5 +/- 10.7 years) and 11 with bulbar onset (mean age 49.6 +/- 11.7 years)-and compared them with 20 healthy, age-matched controls (mean age 46.0 +/- 12.6 years). We assessed central motor conduction time (CMCT), threshold to stimulation, and silent period using transcranial magnetic stimulation. Diffusion tensor MRI was performed using a 1.5-T GE Signa system (Milwaukee, WI) fitted with Advanced NMR hardware and software capable of producing echo planar MR images. Data were acquired from seven coronal slices centered to include the posterior limb of the internal capsule. Maps of the mean diffusivity, fractional anisotropy, and T2-weighted signal intensity were generated. RESULTS There were no differences between the subject groups on measures of CMCT, threshold to stimulation, and silent period. However, the CMCT correlated with clinical measures of UMN involvement. We found a significant increase in the mean diffusivity and reduction in fractional anisotropy along the corticospinal tracts between the three subject groups, most marked in the bulbar-onset group. The fractional anisotropy correlated with measures of disease severity and UMN involvement, whereas the mean diffusivity correlated with disease duration. CONCLUSION The results support the use of diffusion tensor MRI in detecting pathology of the corticospinal tracts in ALS.
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Affiliation(s)
- C M Ellis
- Department of Clinical Neurosciences, Institute of Psychiatry, and Guy's, King's and St. Thomas' School of Medicine, London, UK
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Abstract
A technique for assessing in vivo fiber connectivity in the human brain is presented. The method utilizes a novel connectivity algorithm that operates in three spatial dimensions and uses estimates of fiber tract orientation and tissue anisotropy, obtained from diffusion tensor magnetic resonance imaging, to establish the pathways of fiber tracts. Sample in vivo connectivity images from healthy human brain are presented that demonstrate connections in the white matter tracts. White matter connectivity information is potentially of interest in the study of a range of neurological, psychiatric, and developmental disorders and shows promise for following the natural history of disease.
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Affiliation(s)
- D K Jones
- Division of Medical Physics, University of Leicester, Leicester Royal Infirmary, United Kingdom
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Wilcock DJ, Jones DK, Horsfield MA, Cherryman GR. Echoplanar MRI in patients with an acute stroke syndrome. Br J Radiol 1999; 72:914-21. [PMID: 10645203 DOI: 10.1259/bjr.72.861.10645203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
An increasing number of patients with an acute stroke syndrome are being admitted to hospitals with on-site echoplanar MRI scanners. In this pictorial review, we describe our experience of an MRI protocol in the first 150 such patients scanned in our hospital. We illustrate some of the advantages of using echoplanar MRI. Diffusion and susceptibility weighted acquisitions may supplement conventional MR sequences by providing useful additional information about the age and location of the lesion, together with a high sensitivity to the presence of blood breakdown products.
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Affiliation(s)
- D J Wilcock
- Department of Radiology, University of Leicester, Leicester Royal Infirmary, UK
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37
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Abstract
A technique for assessing in vivo fiber connectivity in the human brain is presented. The method utilizes a novel connectivity algorithm that operates in three spatial dimensions and uses estimates of fiber tract orientation and tissue anisotropy, obtained from diffusion tensor magnetic resonance imaging, to establish the pathways of fiber tracts. Sample in vivo connectivity images from healthy human brain are presented that demonstrate connections in the white matter tracts. White matter connectivity information is potentially of interest in the study of a range of neurological, psychiatric, and developmental disorders and shows promise for following the natural history of disease.
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Affiliation(s)
- D K Jones
- Division of Medical Physics, University of Leicester, Leicester Royal Infirmary, United Kingdom
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Jones DK, Lythgoe D, Horsfield MA, Simmons A, Williams SC, Markus HS. Characterization of white matter damage in ischemic leukoaraiosis with diffusion tensor MRI. Stroke 1999; 30:393-7. [PMID: 9933277 DOI: 10.1161/01.str.30.2.393] [Citation(s) in RCA: 164] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Information on the neuropathological changes underlying ischemic leukoaraiosis is only available postmortem, and there are limited data on histological appearances early in the disease. Diffusion tensor imaging allows determination of the directionality of diffusion, which is greater in the direction of white matter bundles. Therefore, the technique might be expected to show loss of anisotropy (directional diffusion) in leukoaraiosis. METHODS Nine patients with ischemic leukoaraiosis (radiological leukoaraiosis and clinical lacunar stroke) and 10 age-matched controls were studied. Diffusion tensor imaging was performed, and maps of diffusion trace and fractional anisotropy were constructed. Mean values of trace and fractional anisotropy were determined in standard regions of the anterior and posterior white matter in both hemispheres. RESULTS In all patients with ischemic leukoaraiosis, a characteristic abnormal pattern was found, with loss of anisotropy and increased trace in the white matter. For example, in the right anterior white matter mean (SD) trace/3 was 1.12 (0.33) x10(-3) mm2 s-1 in patients and 0.75 (0.11) in controls (P=0.001). In the same region, fractional anisotropy was 0.53 (0.11) in patients and 0.78 (0.09) in controls (P<0.001). Within the white matter regions, there was a strong negative correlation between mean diffusivity and anisotropy (r=-0.92, P<0.0001). CONCLUSIONS The characteristic pattern found on diffusion tensor imaging in this patient group is consistent with axonal loss and gliosis leading to impairment to and loss of directional diffusion. The "in vivo histological" information obtained may be useful in monitoring disease progression and in investigating the pathogenesis of the cognitive impairment that may be present.
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Affiliation(s)
- D K Jones
- Division of Medical Physics, Leicester Royal Infirmary, Leicester, UK
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Abstract
An efficient expression system [D. A. Dalton et al. Arch. Biochem. Biophys. 328, 1-8, 1996) for soybean nodule ascorbate peroxidase (APX) has, for the first time, been used to generate enzyme in large enough quantities for detailed biophysical analysis. The recombinant APX has been characterized by electronic absorption, EPR, NMR and circular dichroism spectroscopies, and by electrochemistry. Electronic, EPR, and NMR spectra are consistent with a high-spin ferric resting state for the enzyme at 298 K. Low-temperature EPR (7 K) and electronic absorption (77 K) experiments indicate formation of a low-spin heme derivative at these temperatures. The midpoint reduction potential for the Fe(III)/Fe(II) redox couple, determined by spectroelectrochemistry, is -159 +/- 2 mV vs SHE (pH 7.0, 25.0 degrees C, mu = 0.10 M). Circular dichroism spectra of pea and soybean APXs are very similar, indicating common structural features for the two enzymes. The melting temperature of soybean APX, as monitored by circular dichroism spectroscopy, is 49 degrees C. These results represent the first detailed spectroscopic and electrochemical analysis of soybean ascorbate peroxidase and are discussed in the broader context of other class I peroxidases.
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Affiliation(s)
- D K Jones
- Department of Chemistry, University of Leicester, University Road, Leicester, LE1 7RH, England, United Kingdom
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Cooper RA, Dvorznak MJ, O'Connor TJ, Boninger ML, Jones DK. Braking electric-powered wheelchairs: effect of braking method, seatbelt, and legrests. Arch Phys Med Rehabil 1998; 79:1244-9. [PMID: 9779678 DOI: 10.1016/s0003-9993(98)90269-6] [Citation(s) in RCA: 18] [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: 02/09/2023]
Abstract
OBJECTIVE To examine the influence of three electric-powered wheelchair braking conditions and four wheelchair seating conditions on electric-powered wheelchair motion and Hybrid II test dummy motion. This study provides quantitative information related to assessing the safety of electric-powered wheelchair driving. DESIGN Rehabilitation engineering comparison and ANSI/ RESNA standards testing. Convenience sample of eight different electric-powered wheelchairs. Within-chair comparisons were conducted. INTERVENTION Electric-powered wheelchairs were compared under three braking scenarios (joystick release, joystick reverse, power-off) and four seating conditions (seatbelt and legrests, seatbelt and no legrests, no seatbelt but legrests, no seatbelt and no legrests). SETTING A rehabilitation engineering center. MAIN OUTCOME MEASURES The braking distance, braking time, and braking accelerations for electric-powered wheelchairs during three braking scenarios; trunk motion, head motion, and trunk angular acceleration during three braking scenarios and four seating conditions; and number of falls from the wheelchairs for three braking scenarios and four seating conditions. RESULTS Significant differences (p < .05) were found in braking distance, braking time, and braking acceleration when comparing the joystick release and joystick reverse scenarios with the power-off scenario. The mean braking distance was shortest with the power-off braking scenario (.89m), whereas it was longest when the joystick was released (1.66m). Significant differences (p < .05) in head displacement and trunk angular displacement were observed among braking conditions and between seating conditions. There were also significant differences (p = .0011) among braking conditions for maximum trunk angular acceleration. The Hybrid II test dummy fell from the wheelchairs with highest frequency when there were no legrests and no seatbelt used. CONCLUSION The results of this study indicate that use of a seatbelt when driving an electric-powered wheelchair reduces the risk of falling from a wheelchair. Furthermore, the use of legrests can reduce the risk of injury to the wheelchair driver. This study shows that the most abrupt braking occurs when deactivating the power switch.
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Affiliation(s)
- R A Cooper
- Department of Rehabilitation Science and Technology, School of Health and Rehabilitation Sciences, University of Pittsburgh, University of Pittsburgh Medical Center Systems PA 15206, USA
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41
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Simmons A, Darekar A, Jones DK, Horsfield MA, Cox TS, Jeffree MA, Williams SCR. Diffusion Tensor MRI Applied to Intra-axial Brain Tumours. Neuroimage 1998. [DOI: 10.1016/s1053-8119(18)31133-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Horsfield MA, Larsson HB, Jones DK, Gass A. Diffusion magnetic resonance imaging in multiple sclerosis. J Neurol Neurosurg Psychiatry 1998; 64 Suppl 1:S80-4. [PMID: 9647291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
This paper reviews the use of magnetic resonance diffusion imaging in studies of multiple sclerosis. Firstly, the principles of diffusion imaging are explained together with a discussion of the hardware and techniques required. The concept of diffusion tensor imaging is introduced and images obtained using this method are presented. Studies that have used diffusion imaging in patients with multiple sclerosis and the implications of the results are discussed. There is an increase in the diffusion coefficient of water molecules in the plaques of patients with multiple sclerosis, compared with healthy brain. Some workers also report increased diffusion in the normal appearing white matter of some patients with multiple sclerosis. Possible mechanisms are given for these findings, together with the experimental evidence to support them.
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Affiliation(s)
- M A Horsfield
- Division of Medical Physics, University of Leicester, Leicester Royal Infirmary, UK
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43
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Abstract
A gene encoding leghaemoglobin a from soybean has been constructed and the soluble recombinant protein expressed in E. coli. The integrity of the recombinant protein has been assessed by a range of spectroscopic techniques. Electrospray mass spectrometry of the protein indicates that the molecular mass of the protein corresponds to the predicted amino acid sequence. Circular dichroism spectra of the ferric derivative and UV-visible spectra of various ferric and ferrous derivatives (pH 6.99, mu = 0.10 M, 25.0 degrees C) are consistent with published data for the wild-type protein. For the ferric derivative, UV-visible (298 and 77 K) and EPR (10 K) spectra indicate the existence of a thermal equilibrium between high- and low-spin forms. Titration of the protein (0.10 M NaCl, mu = 0.10 M, 25.0 degrees C) between pHs 6.68 and 10.35 indicate formation (pKa = 8.3+/-0.03) of a 6-coordinate, hydroxide-bound form of the protein at high pH. All of the above data are consistent with the behaviour of the wild-type protein.
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Affiliation(s)
- D K Jones
- Department of Chemistry, University of Leicester, University Road, Leicester, LE1 7RH, England, U.K
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Krige D, Mills HR, Berrie EL, Doherty NC, Jones DK, Ryan CA, Davies H, Myint S, McCance DJ, Layton GT, French TJ. Sequence variation in the early genes E1E4, E6 and E7 of human papilloma virus type 6. Virus Res 1997; 49:187-91. [PMID: 9213393 DOI: 10.1016/s0168-1702(97)01469-x] [Citation(s) in RCA: 6] [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: 02/04/2023]
Abstract
The majority of condylomata acuminata (anogenital warts) are caused by infection with Human Papilloma Virus type 6 (HPV-6). We have sequenced the HPV-6 early genes, E1-E4, E6 and E7 from wart biopsy DNA samples sourced from the UK and USA and derived a consensus sequence for these genes and the proteins they encode. When compared to the prototype HPV-6b sequence, published over 12 years ago, the E1-E4 consensus sequence showed 3/91 (3.3%) amino acid changes, the E6 consensus sequence showed 1/150 (0.7%) changes and the E7 consensus sequence showed 1/98 (1.0%) changes. Since many of the early gene sequences from biopsy material were more similar to the HPV-6a subtype than HPV-6b, this data supports the use of HPV-6a as the HPV-6 prototype.
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Affiliation(s)
- D Krige
- British Biotech Pharmaceuticals Ltd., Oxford, UK
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45
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Jones DK, Dunn MI. 'Vampire syndrome': serum protein and lipid abnormalities related to frequent sale of plasma. J Fam Pract 1995; 40:288-290. [PMID: 7876787] [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: 05/22/2023]
Abstract
The sale of plasma for profit has become a common occurrence. In the United States, a healthy individual can donate as frequently as six times per month and up to 60 L of plasma per year. Although plasma donors are generally healthy, intervening conditions can increase the catabolism or decrease the synthesis of certain serum constituents and thereby produce a confusing clinical picture. In 1 month, we encountered two patients who presented with hypoalbuminemia and hypocholesterolemia for which there was no obvious cause except a history of frequent plasma sales.
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Affiliation(s)
- D K Jones
- Department of Internal Medicine, University of Kansas Medical Center, Kansas City 66103
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Hoffman GD, Jones DK. Prebilling DRG training can increase hospital reimbursement. Healthc Financ Manage 1993; 47:58, 60, 62. [PMID: 10145870] [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: 02/11/2023]
Abstract
Over the past decade, appropriate reimbursement has become increasingly dependent on accurate coding and correct DRG assignment. In this article, a study outlining the cost of inaccurate coding is presented, and a program for prebilling coder training is described. The authors show that a well-designed prebilling coding program can improve the accuracy of DRG assignment and thereby increase reimbursement by 10 percent or more.
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Jones DK, Perry EM, Grosso MA, Voelkel NF. Release of von Willebrand factor antigen (vWF:Ag) and eicosanoids during acute injury to the isolated rat lung. Am Rev Respir Dis 1992; 145:1410-5. [PMID: 1596010 DOI: 10.1164/ajrccm/145.6.1410] [Citation(s) in RCA: 9] [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] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
It has been suggested that the von Willebrand factor antigen (vWF:Ag) may be a clinical marker for pulmonary endothelial cell injury. An ELISA was developed for the measurement of rat vWF:Ag. Rat lungs were isolated and perfused with a recirculating, blood-free, physiologic salt solution. Circulating levels of vWF:Ag and the eicosanoids thromboxane B2 (TXB2) and prostaglandin 6-keto F1-alpha (6-keto PGF1 alpha) were measured before and after different forms of insult. The addition of phospholipase C (PLC) or hydrogen peroxide (H2O2) to the perfusate caused lung damage as manifested by pulmonary artery pressure increase and pulmonary edema. This was paralleled by significant release of vWF:Ag, TXB2, and 6-keto PGF1 alpha. Increased hydrostatic pressure caused pulmonary edema without vWF:Ag and eicosanoid release. The addition of vasopressin to the perfusate caused vWF:Ag release but no lung injury and no release of eicosanoids. It is concluded that in the rat model, vWF:Ag release is a nonspecific marker for lung injury.
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Affiliation(s)
- D K Jones
- Cardiovascular Pulmonary Research Laboratory, University of Colorado Health Sciences Center, Denver 80262
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Mulvin DW, Jones DK, Howard RB, Grosso MA, Repine JE, Johnston MR. Extracellular flush solution that contains blood, mannitol, albumin, and prostacyclin protects rat lungs from six hours of ischemia. J Heart Lung Transplant 1991; 10:986-9. [PMID: 1756165] [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: 12/28/2022] Open
Abstract
We have used an isolated rat lung model to compare the quality of preservation of different flush techniques with each other and with topical cooling alone. Lung injury was assessed by recording lung weights after reperfusion after 4 and 6 hours of ischemia. The flush solutions studied were intracellular (Collins-Sacks), traditional extracellular, extracellular with low potassium plus dextran, and extracellular containing blood, mannitol, albumin, and prostacyclin (Wallwork's solution). Flushing with Wallwork's solution before both 4 and 6 hours of ischemia gave superior protection from lung edema after reperfusion over all the other methods.
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Affiliation(s)
- D W Mulvin
- Department of Surgery, University of Colorado Health Sciences Centre, Denver 80262
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Jones DK. New ways to work. Job sharing: a personal view. Health Visit 1991; 64:116. [PMID: 2032849] [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: 12/29/2022]
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Abstract
Numerous pulmonary metastases entirely confined to one lobe are rare. A case is presented in which numerous pulmonary metastases from renal cell carcinoma were initially confused radiologically with lobar pneumonia.
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Affiliation(s)
- R Toye
- Academic Department of Radiology, St Bartholomew's Hospital, London
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