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Mancuso M, Cruciani A, Sveva V, Casula E, Brown KE, Di Lazzaro V, Rothwell JC, Rocchi L. Changes in Cortical Activation by Transcranial Magnetic Stimulation Due to Coil Rotation Are Not Attributable to Cranial Muscle Activation. Brain Sci 2024; 14:332. [PMID: 38671984 PMCID: PMC11048461 DOI: 10.3390/brainsci14040332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2024] [Revised: 03/26/2024] [Accepted: 03/27/2024] [Indexed: 04/28/2024] Open
Abstract
Transcranial magnetic stimulation coupled with electroencephalography (TMS-EEG) allows for the study of brain dynamics in health and disease. Cranial muscle activation can decrease the interpretability of TMS-EEG signals by masking genuine EEG responses and increasing the reliance on preprocessing methods but can be at least partly prevented by coil rotation coupled with the online monitoring of signals; however, the extent to which changing coil rotation may affect TMS-EEG signals is not fully understood. Our objective was to compare TMS-EEG data obtained with an optimal coil rotation to induce motor evoked potentials (M1standard) while rotating the coil to minimize cranial muscle activation (M1emg). TMS-evoked potentials (TEPs), TMS-related spectral perturbation (TRSP), and intertrial phase clustering (ITPC) were calculated in both conditions using two different preprocessing pipelines based on independent component analysis (ICA) or signal-space projection with source-informed reconstruction (SSP-SIR). Comparisons were performed with cluster-based correction. The concordance correlation coefficient was computed to measure the similarity between M1standard and M1emg TMS-EEG signals. TEPs, TRSP, and ITPC were significantly larger in M1standard than in M1emg conditions; a lower CCC than expected was also found. These results were similar across the preprocessing pipelines. While rotating the coil may be advantageous to reduce cranial muscle activation, it may result in changes in TMS-EEG signals; therefore, this solution should be tailored to the specific experimental context.
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Affiliation(s)
- Marco Mancuso
- Department of Human Neuroscience, University of Rome “Sapienza”, Viale dell’Università 30, 00185 Rome, Italy;
| | - Alessandro Cruciani
- Unit of Neurology, Neurophysiology, Neurobiology, and Psychiatry, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo 21, 00128 Rome, Italy; (A.C.); (V.D.L.)
- Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo 200, 00128 Rome, Italy
| | - Valerio Sveva
- Department of Anatomical and Histological Sciences, Legal Medicine and Orthopedics, University of Rome “Sapienza”, Piazzale Aldo Moro 5, 00185 Rome, Italy;
| | - Elias Casula
- Department of System Medicine, “Tor Vergata” University of Rome, Via Montpellier 1, 00133 Rome, Italy;
| | - Katlyn E. Brown
- Department of Kinesiology, University of Waterloo, 200 University Ave W, Waterloo, ON N2L 3G5, Canada;
| | - Vincenzo Di Lazzaro
- Unit of Neurology, Neurophysiology, Neurobiology, and Psychiatry, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo 21, 00128 Rome, Italy; (A.C.); (V.D.L.)
- Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo 200, 00128 Rome, Italy
| | - John C. Rothwell
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK;
| | - Lorenzo Rocchi
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK;
- Department of Medical Sciences and Public Health, University of Cagliari, Cittadella Universitaria di Monserrato, Blocco I S.S. 554 bivio per Sestu, Monserrato, 09042 Cagliari, Italy
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Breslin G, Wills W, Bontoft C, Fakoya O, Greco HA, Lloyd N, Wagner AP, Wellings A, Harding S, Brown KE. Whole systems approach to diet and healthy weight: a longitudinal process evaluation in East Scotland. Perspect Public Health 2023; 143:347-357. [PMID: 37902308 PMCID: PMC10683340 DOI: 10.1177/17579139231203858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2023]
Abstract
AIMS Obesity contributes to morbidity and early mortality, affecting people of all ages and sociodemographic backgrounds. Despite attempts to address obesity, efforts to date have only had limited success. Adopting a whole systems approach (WSA) may potentially address obesity and emphasise complex inter-relating factors beyond individual choice. This study aimed to assess implementation of WSA to diet and healthy weight in two council areas of Scotland, longitudinally exploring enablers and barriers. One area followed a Leeds Beckett WSA model (LBM) of implementation, while the other used a hybrid model incorporating existing working systems. METHODS To assess the process of implementing a WSA, interviews and focus groups were conducted after initiation and 1 year later. RESULTS Main enablers included: belief in WSA effectiveness; positive relationships between key personnel; buy-in at community and national levels; funding availability; the working group responsible for coordinating the system development comprising individuals with diverse expertise; good communication; and existing governance structures. Barriers included: insufficient funding; high staff turnover; inadequate training in WSA methodology; engaging all relevant stakeholders and reverting to 'old ways' of non-WSA working. The LBM provided a framework for system setup and generating an action plan. CONCLUSION This study provides the first independent longitudinal process evaluation of WSAs that have incorporated Leeds Beckett methodology, and offers insights into how a WSA can be implemented to address diet and healthy weight.
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Affiliation(s)
- G Breslin
- School of Psychology, Queen’s University Belfast, Belfast, UK
| | - W Wills
- School of Health and Social Work, University of Hertfordshire, Hatfield, UK; Applied Research Collaboration (ARC) East of England, National Institute for Health and Care Research (NIHR), London, UK
| | - C Bontoft
- Department of Psychology, Sport and Geography, School of Life and Medical Sciences, University of Hertfordshire, College Lane Campus, College Lane, Hatfield AL10 9AB, UK
| | - O Fakoya
- Department of Psychology, Sport and Geography, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
| | - H-A Greco
- Department of Psychology, Sport and Geography, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
| | - N Lloyd
- Department of Psychology, Sport and Geography, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
| | - AP Wagner
- Applied Research Collaboration (ARC) East of England, National Institute for Health and Care Research (NIHR), London, UK; Norwich Medical School, University of East Anglia, Norwich, UK
| | - A Wellings
- Department of Psychology, Sport and Geography, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
| | - S Harding
- Department of Psychology, Sport and Geography, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
| | - KE Brown
- Department of Psychology, Sport and Geography, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
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Kaethler LB, Brown KE, Meehan SK, Staines WR. Investigating Cerebellar Modulation of Premovement Beta-Band Activity during Motor Adaptation. Brain Sci 2023; 13:1523. [PMID: 38002483 PMCID: PMC10669216 DOI: 10.3390/brainsci13111523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 10/16/2023] [Accepted: 10/23/2023] [Indexed: 11/26/2023] Open
Abstract
Enhancing cerebellar activity influences motor cortical activity and contributes to motor adaptation, though it is unclear which neurophysiological mechanisms contributing to adaptation are influenced by the cerebellum. Pre-movement beta event-related desynchronization (β-ERD), which reflects a release of inhibitory control in the premotor cortex during movement planning, is one mechanism that may be modulated by the cerebellum through cerebellar-premotor connections. We hypothesized that enhancing cerebellar activity with intermittent theta burst stimulation (iTBS) would improve adaptation rates and increase β-ERD during motor adaptation. Thirty-four participants were randomly assigned to an active (A-iTBS) or sham cerebellar iTBS (S-iTBS) group. Participants performed a visuomotor task, using a joystick to move a cursor to targets, prior to receiving A-iTBS or S-iTBS, following which they completed training with a 45° rotation to the cursor movement. Behavioural adaptation was assessed using the angular error of the cursor path relative to the ideal trajectory. The results showed a greater adaptation rate following A-iTBS and an increase in β-ERD, specific to the high β range (20-30 Hz) during motor planning, compared to S-iTBS, indicative of cerebellar modulation of the motor cortical inhibitory control network. The enhanced release of inhibitory activity persisted throughout training, which suggests that the cerebellar influence over the premotor cortex extends beyond adaptation to other stages of motor learning. The results from this study further understanding of cerebellum-motor connections as they relate to acquiring motor skills and may inform future skill training and rehabilitation protocols.
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Affiliation(s)
| | | | | | - W. Richard Staines
- Department of Kinesiology and Health Sciences, University of Waterloo, 200 University Ave. W., Waterloo, ON N2L 3G1, Canada; (L.B.K.); (K.E.B.); (S.K.M.)
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4
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Ibáñez J, Zicher B, Brown KE, Rocchi L, Casolo A, Del Vecchio A, Spampinato D, Vollette CA, Rothwell JC, Baker SN, Farina D. Standard intensities of transcranial alternating current stimulation over the motor cortex do not entrain corticospinal inputs to motor neurons. J Physiol 2023; 601:3187-3199. [PMID: 35776944 DOI: 10.1113/jp282983] [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: 02/14/2022] [Accepted: 06/22/2022] [Indexed: 11/08/2022] Open
Abstract
Transcranial alternating current stimulation (TACS) is commonly used to synchronize a cortical area and its outputs to the stimulus waveform, but gathering evidence for this based on brain recordings in humans is challenging. The corticospinal tract transmits beta oscillations (∼21 Hz) from the motor cortex to tonically contracted limb muscles linearly. Therefore, muscle activity may be used to measure the level of beta entrainment in the corticospinal tract due to TACS over the motor cortex. Here, we assessed whether TACS is able to modulate the neural inputs to muscles, which would provide indirect evidence for TACS-driven neural entrainment. In the first part of the study, we ran simulations of motor neuron (MN) pools receiving inputs from corticospinal neurons with different levels of beta entrainment. Results suggest that MNs are highly sensitive to changes in corticospinal beta activity. Then, we ran experiments on healthy human subjects (N = 10) in which TACS (at 1 mA) was delivered over the motor cortex at 21 Hz (beta stimulation), or at 7 Hz or 40 Hz (control conditions) while the abductor digiti minimi or the tibialis anterior muscle were tonically contracted. Muscle activity was measured using high-density electromyography, which allowed us to decompose the activity of pools of motor units innervating the muscles. By analysing motor unit pool activity, we observed that none of the TACS conditions could consistently alter the spectral contents of the common neural inputs received by the muscles. These results suggest that 1 mA TACS over the motor cortex given at beta frequencies does not entrain corticospinal activity. KEY POINTS: Transcranial alternating current stimulation (TACS) is commonly used to entrain the communication between brain regions. It is challenging to find direct evidence supporting TACS-driven neural entrainment due to the technical difficulties in recording brain activity during stimulation. Computational simulations of motor neuron pools receiving common inputs in the beta (∼21 Hz) band indicate that motor neurons are highly sensitive to corticospinal beta entrainment. Motor unit activity from human muscles does not support TACS-driven corticospinal entrainment.
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Affiliation(s)
- Jaime Ibáñez
- BSICoS group, I3A Institute, University of Zaragoza, IIS Aragón, Zaragoza, Spain
- Department of Bioengineering, Imperial College, London, UK
- Department for Clinical and movement neurosciences, Institute of Neurology, University College London, UK
| | - Blanka Zicher
- Department of Bioengineering, Imperial College, London, UK
| | - Katlyn E Brown
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - Lorenzo Rocchi
- Department for Clinical and movement neurosciences, Institute of Neurology, University College London, UK
- Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy
| | - Andrea Casolo
- Department of Biomedical Sciences, University of Padova, Padua, Italy
| | - Alessandro Del Vecchio
- Department of Artificial Intelligence in Biomedical Engineering, Faculty of Engineering, 17 Friedrich-Alexander University, Erlangen, Germany
| | - Danny Spampinato
- Non-Invasive Brain Stimulation Unit, Department of Behavioral and Clinical Neurology, Santa Lucia Foundation, Rome, Italy
| | | | | | - Stuart N Baker
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
| | - Dario Farina
- Department of Bioengineering, Imperial College, London, UK
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5
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Neva JL, Brown KE, Peters S, Feldman SJ, Mahendran N, Boisgontier MP, Boyd LA. Acute Exercise Modulates the Excitability of Specific Interneurons in Human Motor Cortex. Neuroscience 2021; 475:103-116. [PMID: 34487820 DOI: 10.1016/j.neuroscience.2021.08.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 08/25/2021] [Accepted: 08/26/2021] [Indexed: 10/20/2022]
Abstract
Acute exercise can modulate the excitability of the non-exercised upper-limb representation in the primary motor cortex (M1). Accumulating evidence demonstrates acute exercise affects measures of M1 intracortical excitability, with some studies also showing altered corticospinal excitability. However, the influence of distinct M1 interneuron populations on the modulation of intracortical and corticospinal excitability following acute exercise is currently unknown. We assessed the impact of an acute bout of leg cycling exercise on unique M1 interneuron excitability of a non-exercised intrinsic hand muscle using transcranial magnetic stimulation (TMS) in young adults. Specifically, posterior-to-anterior (PA) and anterior-to-posterior (AP) TMS current directions were used to measure the excitability of distinct populations of interneurons before and after an acute bout of exercise or rest. Motor evoked potentials (MEPs) and short-interval intracortical inhibition (SICI) were measured in the PA and AP current directions in M1 at two time points separated by 25 min of rest, as well as immediately and 30 min after a 25-minute bout of moderate-intensity cycling exercise. Thirty minutes after exercise, MEP amplitudes were significantly larger than other timepoints when measured with AP current, whereas MEP amplitudes derived from PA current did not show this effect. Similarly, SICI was significantly decreased immediately following acute exercise measured with AP but not PA current. Our findings suggest that the excitability of unique M1 interneurons are differentially modulated by acute exercise. These results indicate that M1 interneurons preferentially activated by AP current may play an important role in the exercise-induced modulation of intracortical and corticospinal excitability.
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Affiliation(s)
- Jason L Neva
- Université de Montréal, École de kinésiologie et des sciences de l'activité physique, Faculté de médecine, Montréal, QC, Canada; Centre de recherche de l'institut universitaire de gériatrie de Montréal, Montréal, QC, Canada.
| | - Katlyn E Brown
- University of Waterloo, Department of Kinesiology, Applied Health Sciences, Waterloo, ON, Canada
| | - Sue Peters
- Rehabilitation Research Program, GF Strong Rehabilitation Centre, Vancouver Coastal Health Research Institute, Vancouver, BC, Canada; University of British Columbia, Department of Physical Therapy, Faculty of Medicine, Vancouver, BC, Canada
| | - Samantha J Feldman
- Graduate Program in Clinical Developmental Neuropsychology, Department of Psychology, York University, Toronto, ON, Canada
| | - Niruthikha Mahendran
- University of Queensland, Discipline of Physiotherapy, School of Health and Rehabilitation Sciences, Brisbane, Australia
| | - Matthieu P Boisgontier
- School of Rehabilitation Sciences, Faculty of Health Sciences, University of Ottawa, Ottawa ON, Canada; Bruyère Research Institute, Ottawa, ON, Canada
| | - Lara A Boyd
- University of British Columbia, Department of Physical Therapy, Faculty of Medicine, Vancouver, BC, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
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6
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Abstract
OBJECTIVES: To investigate neurophysiological alterations within the typical symptomatic period after concussion (1-month) and throughout recovery (6-months) in adolescents; and (2) to examine relationships between neurophysiological and upper limb kinematic outcomes.METHODS: 18 adolescents with concussion were compared to 17 healthy controls. Transcranial magnetic stimulation (TMS) was used to assess neurophysiological differences between groups including: short- and long-interval intracortical inhibition, intracortical facilitation, short- and long-latency afferent inhibition, afferent facilitation, and transcallosal inhibition (TCI). Behavioral measures of upper limb kinematics were assessed with a robotic device.RESULTS: Mixed model analysis of neurophysiological data identified two key findings. First, participants with concussion demonstrated delayed onset of interhemispheric inhibition, as indexed by TCI, compared to healthy controls. Second, our exploratory analysis indicated that the magnitude of TCI onset delay in adolescents with concussion was related to upper limb kinematics.CONCLUSIONS: Our findings indicate that concussion in adolescence alters interhemispheric communication. We note relationships between neurophysiological and kinematic data, suggesting an affinity for individuals with less concussion-related physiological change to improve their motor behavior over time. These data serve as an important step in future development of assessments (neurobiological and clinical) and interventions for concussion.
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Affiliation(s)
- Julia Schmidt
- Department of Occupational Science and Occupational Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Katlyn E Brown
- Sobell Department of Motor Neuroscience and Movement Disorders, University College London, London, UK.,Graduate Program in Rehabilitation Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Samantha J Feldman
- Graduate Program in Neuroscience, University of British Columbia, Vancouver, British Columbia, Canada
| | - Shelina Babul
- BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Emergency Medicine, BC Children's Hospital, Vancouver, British Columbia, Canada.,Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jill G Zwicker
- Department of Occupational Science and Occupational Therapy, University of British Columbia, Vancouver, British Columbia, Canada.,BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada.,Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada.,Sunny Hill Health Centre at BC Children's Hospital, Vancouver, British Columbia, Canada
| | - Lara A Boyd
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
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7
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Hordacre B, Austin D, Brown KE, Graetz L, Parees I, De Trane S, Vallence AM, Koblar S, Kleinig T, McDonnell MN, Greenwood R, Ridding MC, Rothwell JC. Evidence for a Window of Enhanced Plasticity in the Human Motor Cortex Following Ischemic Stroke. Neurorehabil Neural Repair 2021; 35:307-320. [PMID: 33576318 PMCID: PMC7610679 DOI: 10.1177/1545968321992330] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [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] [Indexed: 12/23/2022]
Abstract
BACKGROUND In preclinical models, behavioral training early after stroke produces larger gains compared with delayed training. The effects are thought to be mediated by increased and widespread reorganization of synaptic connections in the brain. It is viewed as a period of spontaneous biological recovery during which synaptic plasticity is increased. OBJECTIVE To look for evidence of a similar change in synaptic plasticity in the human brain in the weeks and months after ischemic stroke. METHODS We used continuous theta burst stimulation (cTBS) to activate synapses repeatedly in the motor cortex. This initiates early stages of synaptic plasticity that temporarily reduces cortical excitability and motor-evoked potential amplitude. Thus, the greater the effect of cTBS on the motor-evoked potential, the greater the inferred level of synaptic plasticity. Data were collected from separate cohorts (Australia and UK). In each cohort, serial measurements were made in the weeks to months following stroke. Data were obtained for the ipsilesional motor cortex in 31 stroke survivors (Australia, 66.6 ± 17.8 years) over 12 months and the contralesional motor cortex in 29 stroke survivors (UK, 68.2 ± 9.8 years) over 6 months. RESULTS Depression of cortical excitability by cTBS was most prominent shortly after stroke in the contralesional hemisphere and diminished over subsequent sessions (P = .030). cTBS response did not differ across the 12-month follow-up period in the ipsilesional hemisphere (P = .903). CONCLUSIONS Our results provide the first neurophysiological evidence consistent with a period of enhanced synaptic plasticity in the human brain after stroke. Behavioral training given during this period may be especially effective in supporting poststroke recovery.
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Affiliation(s)
- Brenton Hordacre
- University of South Australia, IIMPACT in Health, Adelaide,
Australia
| | - Duncan Austin
- UCL Institute of Neurology, Queen Square, London, UK
| | | | - Lynton Graetz
- Lifespan Human Neurophysiology group, Adelaide Medical
School, The University of Adelaide, Australia
| | - Isabel Parees
- Servicio de Neurologia, Hospital Universitario Ramón
y Cajal, Madrid, Spain
- Servicio de Neurología, Hospital Ruber
Internacional, Madrid, Spain
| | - Stefania De Trane
- The Blizard Institute, Barts and The London School of
Medicine & Dentistry, Queen Mary University of London, London, UK
- Clinical Board: Medicine (Neuroscience), The Royal London
Hospital, Barts Health NHS Trust, London, UK
- National Hospital for Neurology and Neurosurgery, Queen
Square, London, UK
| | - Ann-Maree Vallence
- Discipline of Psychology, College of Science, Health,
Engineering and Education, Murdoch University, Western Australia, Australia
| | - Simon Koblar
- Department of Medicine, The University of Adelaide,
Adelaide, Australia
- Department of Neurology, Royal Adelaide Hospital,
Adelaide, Australia
| | - Timothy Kleinig
- Department of Medicine, The University of Adelaide,
Adelaide, Australia
- Department of Neurology, Royal Adelaide Hospital,
Adelaide, Australia
| | | | - Richard Greenwood
- National Hospital for Neurology and Neurosurgery, Queen
Square, London, UK
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8
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De Doncker W, Brown KE, Kuppuswamy A. Influence of post-stroke fatigue on reaction times and corticospinal excitability during movement preparation. Clin Neurophysiol 2020; 132:191-199. [PMID: 33302061 PMCID: PMC7810236 DOI: 10.1016/j.clinph.2020.11.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [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] [Received: 06/01/2020] [Revised: 10/07/2020] [Accepted: 11/16/2020] [Indexed: 11/20/2022]
Abstract
Higher the fatigue, lesser the inhibition in movement preparation in stroke survivors. Higher the fatigue, lesser the pre-movement facilitation and slower the reaction times. Poor excitability modulation supports sensory attenuation model of fatigue.
Objectives Reduced corticospinal excitability at rest is associated with post-stroke fatigue (PSF). However, it is not known if corticospinal excitability prior to a movement is also altered in fatigue which may then influence subsequent behaviour. We hypothesized that the levels of PSF can be explained by differences in modulation of corticospinal excitability during movement preparation. Methods 73 stroke survivors performed an auditory reaction time task. Corticospinal excitability was measured using transcranial magnetic stimulation. Fatigue was quantified using the fatigue severity scale. The effect of time and fatigue on corticospinal excitability and reaction time was analysed using a mixed effects model. Results Those with greater levels of PSF showed reduced suppression of corticospinal excitability during movement preparation and increased facilitation immediately prior to movement onset (β = −0.0066, t = −2.22, p = 0.0263). Greater the fatigue, slower the reaction times the closer the stimulation time to movement onset (β = 0.0024, t = 2.47, p = 0.0159). Conclusions Lack of pre-movement modulation of corticospinal excitability in high fatigue may indicate poor sensory processing supporting the sensory attenuation model of fatigue. Significance We take a systems-based approach and investigate the motor system and its role in pathological fatigue allowing us to move towards gaining a mechanistic understanding of chronic pathological fatigue.
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Affiliation(s)
- William De Doncker
- Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, UK.
| | - Katlyn E Brown
- Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, UK; University of Waterloo, Department of Kinesiology, Faculty of Applied Health Sciences, Waterloo, ON, Canada
| | - Annapoorna Kuppuswamy
- Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, UK
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9
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Brown KE, Neva JL, Mang CS, Chau B, Chiu LK, Francisco BA, Staines WR, Boyd LA. The influence of an acute bout of moderate-intensity cycling exercise on sensorimotor integration. Eur J Neurosci 2020; 52:4779-4790. [PMID: 32692429 DOI: 10.1111/ejn.14909] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 07/06/2020] [Indexed: 01/09/2023]
Abstract
Acute cycling exercise can modulate motor cortical circuitry in the non-exercised upper-limb. Within the primary motor cortex, measures of intracortical inhibition are reduced and intracortical facilitation is enhanced following acute exercise. Further, acute cycling exercise decreases interhemispheric inhibition between the motor cortices and lowers cerebellar-to-motor cortex inhibition. Yet, investigations into the effects of acute exercise on sensorimotor integration, referring to the transfer of incoming afferent information from the primary somatosensory cortex to motor cortex, are lacking. The current work addresses this gap in knowledge with two experimental sessions. In the first session, we tested the exercise-induced changes in somatosensory and motor excitability by assessing somatosensory (SEP) and motor evoked potentials (MEPs). In the second session, we explored the effects of acute cycling exercise on short- (SAI) and long-latency afferent inhibition (LAI), and afferent facilitation. In both experimental sessions, neurophysiological measures were obtained from the non-exercised upper-limb muscle, tested at two time points pre-exercise separated by a 25-min period of rest. Next, a 25-min bout of moderate-intensity lower-limb cycling was performed with measures assessed at two time points post-exercise. Acute lower-limb cycling increased LAI, without modulation of SAI or afferent facilitation. Further, there were no exercise-induced changes to SEP or MEP amplitudes. Together, these results suggest that acute exercise has unique effects on sensorimotor integration, which are not accompanied by concurrent changes in somatosensory or motor cortical excitability.
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Affiliation(s)
- Katlyn E Brown
- Department of Kinesiology, Faculty of Applied Health Sciences, University of Waterloo, Waterloo, ON, Canada
| | - Jason L Neva
- École de Kinésiologie et des Sciences de l'activité Physique, Faculté de médecine, Université de Montréal, Montréal, QC, Canada.,Centre de Recherche de l'institut Universitaire de Gériatrie de Montréal, Montréal, QC, Canada
| | - Cameron S Mang
- Department of Kinesiology and Health Studies, University of Regina, Regina, SK, Canada
| | - Briana Chau
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Larissa K Chiu
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Beatrice A Francisco
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - William R Staines
- Department of Kinesiology, Faculty of Applied Health Sciences, University of Waterloo, Waterloo, ON, Canada
| | - Lara A Boyd
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.,The Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
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10
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Neva JL, Brown KE, Wadden KP, Mang CS, Borich MR, Meehan SK, Boyd LA. The effects of five sessions of continuous theta burst stimulation over contralesional sensorimotor cortex paired with paretic skilled motor practice in people with chronic stroke. Restor Neurol Neurosci 2020; 37:273-290. [PMID: 31227676 DOI: 10.3233/rnn-190916] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND In individuals with chronic stroke, impairment of the paretic arm may be exacerbated by increased contralesional transcallosal inhibition (TCI). Continuous theta burst stimulation (cTBS) can decrease primary motor cortex (M1) excitability and TCI. However, contralesional cTBS shows inconsistent effects after stroke. Variable effects of cTBS could stem from failure to pair stimulation with skilled motor practice or a focus of applying cTBS over M1. OBJECTIVE Here, we investigated the effects of pairing cTBS with skilled practice on motor learning and arm function. We considered the differential effects of stimulation over two different brain regions: contralesional M1 (M1c) or contralesional primary somatosensory cortex (S1c). METHODS 37 individuals with chronic stroke participated in five sessions of cTBS and paretic arm skilled practice of a serial targeting task (STT); participants received either cTBS over M1c or S1c or sham before STT practice. Changes in STT performance and Wolf Motor Function Test (WMFT) were assessed as primary outcomes. Assessment of bilateral corticospinal, intracortical excitability and TCI were secondary outcomes. RESULTS cTBS over sensorimotor cortex did not improve STT performance and paretic WMFT-rate beyond sham cTBS. TCI was reduced bi-directionally following the intervention, regardless of stimulation group. In addition, we observed an association between STT performance change and paretic WMFT-rate change in the M1c stimulation group only. CONCLUSIONS Multiple sessions of STT practice can improve paretic arm function and decrease TCI bilaterally, with no additional benefit of prior cTBS. Our results suggest that improvement in STT practice following M1c cTBS scaled with change in paretic arm function in some individuals. Our results highlight the need for a better understanding of the mechanisms of cTBS to effectively identify who may benefit from this form of brain stimulation.
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Affiliation(s)
- J L Neva
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - K E Brown
- Graduate Studies in Rehabilitation Sciences, University of British Columbia, Vancouver Canada
| | - K P Wadden
- Graduate Studies in Rehabilitation Sciences, University of British Columbia, Vancouver Canada
| | - C S Mang
- Graduate Studies in Rehabilitation Sciences, University of British Columbia, Vancouver Canada.,Division of Physical Medicine and Rehabilitation, Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - M R Borich
- Department of Rehabilitation Medicine, Division of Physical Therapy, School of Medicine, Emory University, Atlanta, GA, USA
| | - S K Meehan
- School of Kinesiology, University of Michigan, Ann Arbor, Michigan, USA
| | - L A Boyd
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.,The Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
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11
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Rocchi L, Latorre A, Ibanez Pereda J, Spampinato D, Brown KE, Rothwell J, Bhatia K. A case of congenital hypoplasia of the left cerebellar hemisphere and ipsilateral cortical myoclonus. Mov Disord 2019; 34:1745-1747. [PMID: 31609490 DOI: 10.1002/mds.27881] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 09/03/2019] [Accepted: 09/09/2019] [Indexed: 12/26/2022] Open
Affiliation(s)
- Lorenzo Rocchi
- Department of Clinical and Movement Neurosciences, University College London Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Anna Latorre
- Department of Clinical and Movement Neurosciences, University College London Queen Square Institute of Neurology, University College London, London, United Kingdom.,Department of Human Neuroscience, University of Rome "Sapienza," Rome, Italy
| | - Jaime Ibanez Pereda
- Department of Clinical and Movement Neurosciences, University College London Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Danny Spampinato
- Department of Clinical and Movement Neurosciences, University College London Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Katlyn E Brown
- Department of Clinical and Movement Neurosciences, University College London Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - John Rothwell
- Department of Clinical and Movement Neurosciences, University College London Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Kailash Bhatia
- Department of Clinical and Movement Neurosciences, University College London Queen Square Institute of Neurology, University College London, London, United Kingdom
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12
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Powell MS, Bowlan PR, Son SF, Bolme CA, Brown KE, Moore DS, McGrane SD. A benchtop shock physics laboratory: Ultrafast laser driven shock spectroscopy and interferometry methods. Rev Sci Instrum 2019; 90:063001. [PMID: 31254979 DOI: 10.1063/1.5092244] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 05/27/2019] [Indexed: 06/09/2023]
Abstract
Common Ti:sapphire chirped pulse amplified laser systems can be readily adapted to be both a generator of adjustable pressure shock waves and a source for multiple probes of the ensuing ultrafast shock dynamics. In this paper, we detail experimental considerations for optimizing the shock generation, interferometric characterization, and spectroscopic probing of shock dynamics with visible and mid-infrared transient absorption. While we have reported results using these techniques elsewhere, here we detail how the spectroscopies are integrated with the shock and interferometry experiment. The interferometric characterization uses information from beams at multiple polarizations and angles of incidence combined with thin film equations and shock dynamics to determine the shock velocity, particle velocity, and shocked refractive index. Visible transient absorption spectroscopy uses a white light supercontinuum in a reflection geometry, synchronized to the shock wave, to time resolve shock-induced changes in visible absorption such as changes to electronic structure or strongly absorbing products and intermediates due to reaction. Mid-infrared transient absorption spectroscopy uses two color filamentation supercontinuum generation combined with a simple thermal imaging microbolometer spectrometer to enable broadband single shot detection of changes in the vibrational spectra. These methods are demonstrated here in the study of shock dynamics at stresses from 5 to 30 GPa in organic materials and from a few GPa to >70 GPa in metals with spatial resolution of a few micrometers and temporal resolution of a few picoseconds. This experiment would be possible to replicate in any ultrafast laser laboratory containing a single bench top commercial chirped pulse amplification laser system.
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Affiliation(s)
- M S Powell
- Maurice J. Zucrow Laboratory, Mechanical Engineering Department, Purdue University, 500 Allison Rd., West Lafayette, Indiana 47907, USA
| | - P R Bowlan
- Physical Chemistry and Applied Spectroscopy, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - S F Son
- Maurice J. Zucrow Laboratory, Mechanical Engineering Department, Purdue University, 500 Allison Rd., West Lafayette, Indiana 47907, USA
| | - C A Bolme
- Shock and Detonation Physics, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - K E Brown
- Shock and Detonation Physics, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - D S Moore
- Shock and Detonation Physics, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - S D McGrane
- Shock and Detonation Physics, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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13
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Kwah KL, Fulton EA, Brown KE. Accessing National Health Service Stop Smoking Services in the UK: a COM-B analysis of barriers and facilitators perceived by smokers, ex-smokers and stop smoking advisors. Public Health 2019; 171:123-130. [PMID: 31128557 DOI: 10.1016/j.puhe.2019.03.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 03/15/2019] [Accepted: 03/20/2019] [Indexed: 10/26/2022]
Abstract
OBJECTIVE Smokers who access free National Health Service (NHS) Stop Smoking Services (SSS) in the UK are four times more likely to stop smoking, yet uptake of the services has been in decline in recent years. Evidence was collated to explore the beliefs of smokers, ex-smokers and Stop Smoking Advisors (SSAs) about SSS and the barriers and facilitators to access. STUDY DESIGN Mixed-methods design including i) a search of the literature; ii) a cross-sectional online questionnaire completed by 38 smokers and ex-smokers; and iii) semistructured interviews with 5 SSAs. METHODS PubMed, Web of Science, Scopus, Prospero and the NIHR Portfolio were searched in October 2017 to identify relevant studies. Smokers and ex-smokers were recruited to the online questionnaire via Public Health websites and social media in Warwickshire. SSAs identified via Public Health Warwickshire were invited to take part in an interview conducted over the telephone. Findings were collated and analysed using the COM-B ('Capability', 'Opportunity', 'Motivation' and 'Behaviour') model framework. RESULTS A range of practical and psychological or belief-based barriers and facilitators to accessing SSS were identified within all the components of the COM-B model, aside from physical capability, for example; 'Psychological capability', such as lack of understanding about what the service offers; 'Reflective motivation', such as lack of confidence in service efficacy; and 'Social opportunity', such as recommendations from healthcare professionals to attend. Suggestions and consideration on how future tobacco control intervention and public health messages can address these components are reported. CONCLUSIONS Public health interventions and campaigns may benefit from focussing on addressing the well-known perceived barriers and facilitators smokers experience, in particular focussing on the components of the COM-B that have been identified as being important to increase the uptake of SSS.
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Affiliation(s)
- K L Kwah
- Centre for Advances in Behavioural Science, Coventry University, Coventry, CV1 5FB, UK.
| | - E A Fulton
- Centre for Advances in Behavioural Science, Coventry University, Coventry, CV1 5FB, UK; Public Health Warwickshire, Warwickshire County Council, Warwick, CV34 4RL, UK
| | - K E Brown
- Centre for Advances in Behavioural Science, Coventry University, Coventry, CV1 5FB, UK; Public Health Warwickshire, Warwickshire County Council, Warwick, CV34 4RL, UK
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14
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Peters S, Brown KE, Garland SJ, Staines WR, Handy TC, Francisco BA, Boyd LA. Cortical processing of irrelevant somatosensory information from the leg is altered by attention during early movement preparation. Brain Res 2019; 1707:45-53. [PMID: 30468723 DOI: 10.1016/j.brainres.2018.11.027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 11/04/2018] [Accepted: 11/19/2018] [Indexed: 11/28/2022]
Abstract
The ability to actively suppress, or gate, irrelevant sensory information is needed for safe and efficient walking in sensory-rich environments. Both attention and the late phase of motor preparation alter somatosensory evoked potentials (SEPs) in healthy adults. The aim of this study was to examine the effect of attention on the processing of irrelevant somatosensory information during the early phase of preparation of plantarflexion movements. Young healthy individuals received tibial nerve stimulation while electroencephalography (EEG) recorded SEPs over the Cz electrode. Three conditions were tested in both legs: 1) Rest, 2) Attend To the stimulated limb, and 3) Attend Away from the stimulated limb. In conditions 2 and 3, vibration (80 Hz) was applied over the medial soleus muscle to cue voluntary plantarflexion movements of the stimulated (Attend To) or non-stimulated leg (Attend Away). Only SEPs delivered during early preparation were averaged for statistical analysis. Results demonstrated a main effect of condition for the N40 and N70 indicating that SEP amplitudes in the Attend To condition were smaller than rest (p ≤ 0.02). For the P50, no interaction effects or main effects were found (p ≥ 0.08). There was no main effect of leg for any component measured. The results indicate that gating of irrelevant sensory information during early preparation occurs in the leg when attention is directed within the same limb. If attention alters the somatosensory stimuli from a leg movement, then directing attention may affect safe community walking.
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Affiliation(s)
- Sue Peters
- Graduate Programs in Rehabilitation Sciences, Faculty of Medicine, University of British Columbia, 212 - 2177 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada.
| | - Katlyn E Brown
- Graduate Programs in Rehabilitation Sciences, Faculty of Medicine, University of British Columbia, 212 - 2177 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada
| | - S Jayne Garland
- Faculty of Health Sciences, Western University, Arthur and Sonia Labatt Health Sciences Building, Room 200, London, ON, N6A 5B9, Canada
| | - W Richard Staines
- Department of Kinesiology, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada
| | - Todd C Handy
- Department of Psychology, Faculty of Arts, University of British Columbia, 2136 West Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Beatrice A Francisco
- Graduate Programs in Rehabilitation Sciences, Faculty of Medicine, University of British Columbia, 212 - 2177 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Lara A Boyd
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, 212 - 2177 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 2215 Wesbrook Ball, Vancouver, BC, V6T IZ3, Canada
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15
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Brown KE, Neva JL, Feldman SJ, Staines WR, Boyd LA. Sensorimotor integration in chronic stroke: Baseline differences and response to sensory training. Restor Neurol Neurosci 2018. [PMID: 29526859 DOI: 10.3233/rnn-170790] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The integration of somatosensory information from the environment into the motor cortex to inform movement is essential for motor function. As motor deficits commonly persist into the chronic phase of stroke recovery, it is important to understand potential contributing factors to these deficits, as well as their relationship with motor function. To date the impact of chronic stroke on sensorimotor integration has not been thoroughly investigated. OBJECTIVES The current study aimed to comprehensively examine the influence of chronic stroke on sensorimotor integration, and determine whether sensorimotor integration can be modified with an intervention. Further, it determined the relationship between neurophysiological measures of sensorimotor integration and motor deficits post-stroke. METHODS Fourteen individuals with chronic stroke and twelve older healthy controls participated. Motor impairment and function were quantified in individuals with chronic stroke. Baseline neurophysiology was assessed using nerve-based measures (short- and long-latency afferent inhibition, afferent facilitation) and vibration-based measures of sensorimotor integration, which paired vibration with single and paired-pulse TMS techniques. Neurophysiological assessment was performed before and after a vibration-based sensory training paradigm to assess changes within these circuits. RESULTS Vibration-based, but not nerve-based measures of sensorimotor integration were different in individuals with chronic stroke, as compared to older healthy controls, suggesting that stroke differentially impacts integration of specific types of somatosensory information. Sensorimotor integration was behaviourally relevant in that it related to both motor function and impairment post-stroke. Finally, sensory training modulated sensorimotor integration in individuals with chronic stroke and controls. CONCLUSION Sensorimotor integration is differentially impacted by chronic stroke based on the type of afferent feedback. However, both nerve-based and vibration-based measures relate to motor impairment and function in individuals with chronic stroke.
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Affiliation(s)
- Katlyn E Brown
- Graduate Program in Rehabilitation Sciences, Faculty of Medicine, University of British Columbia, Vancouver, Canada
| | - Jason L Neva
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Samantha J Feldman
- Graduate Program in Neuroscience, Faculty of Medicine, University of British Columbia, Vancouver, Canada
| | - W Richard Staines
- Department of Kinesiology, Faculty of Applied Health Sciences, University of Waterloo, Waterloo, Ontario, Canada
| | - Lara A Boyd
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
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16
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Peters S, Brown KE, Garland SJ, Staines WR, Handy TC, Boyd LA. Suppression of somatosensory stimuli during motor planning may explain levels of balance and mobility after stroke. Eur J Neurosci 2018; 48:3534-3551. [PMID: 30151944 DOI: 10.1111/ejn.14136] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 08/10/2018] [Accepted: 08/16/2018] [Indexed: 12/01/2022]
Abstract
The ability to actively suppress, or gate, irrelevant sensory information is required for safe and efficient walking in sensory-rich environments. Both motor attention and motor planning alter somatosensory evoked potentials (SEPs) in healthy adults. This study's aim was to examine the effect of motor attention on processing of irrelevant somatosensory information during plantar flexion motor planning after stroke. Thirteen healthy older adults and 11 individuals with stroke participated. Irrelevant tibial nerve stimulation was delivered while SEPs were recorded over Cz, overlaying the leg portion of the sensorimotor cortex at the vertex of the head. Three conditions were tested in both legs: (1) Rest, (2) Attend To, and (3) Attend Away from the stimulated limb. In conditions 2 and 3, relevant vibration cued voluntary plantar flexion movements of the stimulated (Attend To) or non-stimulated (Attend Away) leg. SEP amplitudes were averaged during motor planning per condition. Individuals with stroke did not show attention-mediated gating of the N40 component associated with irrelevant somatosensory information during motor planning. It may be that dysfunction in pathways connecting to area 3b explains the lack of attention-mediated gating of the N40. Also, attention-mediated gating during motor planning explained significant and unique variance in a measure of community balance and mobility combined with response time. Thus, the ability to gate irrelevant somatosensory information appears important for stepping in both older adults and after stroke. Our data suggest that therapies that direct motor attention could positively impact walking after stroke.
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Affiliation(s)
- Sue Peters
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Katlyn E Brown
- Graduate Programs in Rehabilitation Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - S Jayne Garland
- Faculty of Health Sciences, Western University, London, Ontario, Canada
| | - W Richard Staines
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - Todd C Handy
- Department of Psychology, Faculty of Arts, University of British Columbia, Vancouver, British Columbia, Canada
| | - Lara A Boyd
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada
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17
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Ferris JK, Peters S, Brown KE, Tourigny K, Boyd LA. Type-2 diabetes mellitus reduces cortical thickness and decreases oxidative metabolism in sensorimotor regions after stroke. J Cereb Blood Flow Metab 2018; 38:823-834. [PMID: 28401788 PMCID: PMC5987933 DOI: 10.1177/0271678x17703887] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Individuals with type-2 diabetes mellitus experience poor motor outcomes after ischemic stroke. Recent research suggests that type-2 diabetes adversely impacts neuronal integrity and function, yet little work has considered how these neuronal changes affect sensorimotor outcomes after stroke. Here, we considered how type-2 diabetes impacted the structural and metabolic function of the sensorimotor cortex after stroke using volumetric magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS). We hypothesized that the combination of chronic stroke and type-2 diabetes would negatively impact the integrity of sensorimotor cortex as compared to individuals with chronic stroke alone. Compared to stroke alone, individuals with stroke and diabetes had lower cortical thickness bilaterally in the primary somatosensory cortex, and primary and secondary motor cortices. Individuals with stroke and diabetes also showed reduced creatine levels bilaterally in the sensorimotor cortex. Contralesional primary and secondary motor cortex thicknesses were negatively related to sensorimotor outcomes in the paretic upper-limb in the stroke and diabetes group such that those with thinner primary and secondary motor cortices had better motor function. These data suggest that type-2 diabetes alters cerebral energy metabolism, and is associated with thinning of sensorimotor cortex after stroke. These factors may influence motor outcomes after stroke.
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Affiliation(s)
- Jennifer K Ferris
- 1 Faculty of Medicine, Graduate program of Rehabilitation Sciences, University of British Columbia, Vancouver, Canada
| | - Sue Peters
- 1 Faculty of Medicine, Graduate program of Rehabilitation Sciences, University of British Columbia, Vancouver, Canada
| | - Katlyn E Brown
- 1 Faculty of Medicine, Graduate program of Rehabilitation Sciences, University of British Columbia, Vancouver, Canada
| | - Katherine Tourigny
- 2 Department of Psychology, University of British Columbia, Vancouver, Canada
| | - Lara A Boyd
- 1 Faculty of Medicine, Graduate program of Rehabilitation Sciences, University of British Columbia, Vancouver, Canada.,3 Department of Physical Therapy, University of British Columbia, Vancouver, Canada.,4 Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
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18
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Schmidt J, Hayward KS, Brown KE, Zwicker JG, Ponsford J, van Donkelaar P, Babul S, Boyd LA. Imaging in Pediatric Concussion: A Systematic Review. Pediatrics 2018; 141:peds.2017-3406. [PMID: 29678928 DOI: 10.1542/peds.2017-3406] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/12/2018] [Indexed: 11/24/2022] Open
Abstract
CONTEXT Pediatric mild traumatic brain injury (mTBI) is a common and poorly understood injury. Neuroimaging indexes brain injury and outcome after pediatric mTBI, but remains largely unexplored. OBJECTIVE To investigate the differences in neuroimaging findings in children/youth with mTBI. Measures of behavior, symptoms, time since injury, and age at injury were also considered. DATA SOURCES A systematic review was conducted up to July 6, 2016. STUDY SELECTION Studies were independently screened by 2 authors and included if they met predetermined eligibility criteria: (1) children/youth (5-18 years of age), (2) diagnosis of mTBI, and (3) use of neuroimaging. DATA EXTRACTION Two authors independently appraised study quality and extracted demographic and outcome data. RESULTS Twenty-two studies met the eligibility criteria, involving 448 participants with mTBI (mean age = 12.7 years ± 2.8). Time postinjury ranged from 1 day to 5 years. Seven different neuroimaging methods were investigated in included studies. The most frequently used method, diffusion tensor imaging (41%), had heterogeneous findings with respect to the specific regions and tracts that showed group differences. However, group differences were observed in many regions containing the corticospinal tract, portions of the corpus callosum, or frontal white-matter regions; fractional anisotropy was increased in 88% of the studies. LIMITATIONS This review included a heterogeneous sample with regard to participant ages, time since injury, symptoms, and imaging methods which prevented statistical pooling/modelling. CONCLUSIONS These data highlight essential priorities for future research (eg, common data elements) that are foundational to progress the understanding of pediatric concussion.
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Affiliation(s)
- Julia Schmidt
- Department of Physical Therapy, The University of British Columbia, Vancouver, Canada; .,School of Allied Health, College of Science, Health and Engineering, La Trobe University, Melbourne, Australia
| | - Kathryn S Hayward
- Department of Physical Therapy, The University of British Columbia, Vancouver, Canada.,Florey Institute of Neuroscience and Mental Health, National Health and Medical Research Council and University of Melbourne, Parkville, Australia.,Centre for Research Excellence in Stroke Rehabilitation and Brain Recovery, Melbourne, Australia
| | - Katlyn E Brown
- Department of Physical Therapy, The University of British Columbia, Vancouver, Canada
| | - Jill G Zwicker
- Department of Physical Therapy, The University of British Columbia, Vancouver, Canada.,BC Children's Hospital Research Institute, Vancouver, Canada; and
| | | | - Paul van Donkelaar
- Department of Physical Therapy, The University of British Columbia, Vancouver, Canada
| | - Shelina Babul
- Department of Physical Therapy, The University of British Columbia, Vancouver, Canada.,BC Children's Hospital Research Institute, Vancouver, Canada; and
| | - Lara A Boyd
- Department of Physical Therapy, The University of British Columbia, Vancouver, Canada
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19
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Francisco BA, Neva JL, Brown KE, Campbell KL, Boyd LA. The Effects of Acute Aerobic Exercise On Primary Motor Cortical Excitability in Healthy Older Adults. Med Sci Sports Exerc 2018. [DOI: 10.1249/01.mss.0000535398.10305.d4] [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: 11/21/2022]
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20
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Brown KE, Lohse KR, Mayer IMS, Strigaro G, Desikan M, Casula EP, Meunier S, Popa T, Lamy JC, Odish O, Leavitt BR, Durr A, Roos RAC, Tabrizi SJ, Rothwell JC, Boyd LA, Orth M. The reliability of commonly used electrophysiology measures. Brain Stimul 2017; 10:1102-1111. [PMID: 28807846 DOI: 10.1016/j.brs.2017.07.011] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [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: 03/28/2017] [Revised: 06/27/2017] [Accepted: 07/27/2017] [Indexed: 10/19/2022] Open
Abstract
BACKGROUND Electrophysiological measures can help understand brain function both in healthy individuals and in the context of a disease. Given the amount of information that can be extracted from these measures and their frequent use, it is essential to know more about their inherent reliability. OBJECTIVE/HYPOTHESIS To understand the reliability of electrophysiology measures in healthy individuals. We hypothesized that measures of threshold and latency would be the most reliable and least susceptible to methodological differences between study sites. METHODS Somatosensory evoked potentials from 112 control participants; long-latency reflexes, transcranial magnetic stimulation with resting and active motor thresholds, motor evoked potential latencies, input/output curves, and short-latency sensory afferent inhibition and facilitation from 84 controls were collected at 3 visits over 24 months at 4 Track-On HD study sites. Reliability was assessed using intra-class correlation coefficients for absolute agreement, and the effects of reliability on statistical power are demonstrated for different sample sizes and study designs. RESULTS Measures quantifying latencies, thresholds, and evoked responses at high stimulator intensities had the highest reliability, and required the smallest sample sizes to adequately power a study. Very few between-site differences were detected. CONCLUSIONS Reliability and susceptibility to between-site differences should be evaluated for electrophysiological measures before including them in study designs. Levels of reliability vary substantially across electrophysiological measures, though there are few between-site differences. To address this, reliability should be used in conjunction with theoretical calculations to inform sample size and ensure studies are adequately powered to detect true change in measures of interest.
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Affiliation(s)
- K E Brown
- Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada
| | - K R Lohse
- College of Health, University of Utah, Salt Lake City, UT, USA
| | - I M S Mayer
- Department of Neurology, Ulm University Hospital, Ulm, Germany; Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, UK
| | - G Strigaro
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, UK
| | - M Desikan
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, UK
| | - E P Casula
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, UK
| | - S Meunier
- APHP Department of Genetics, Groupe Hospitalier Pitié-Salpêtrière, Institut du Cerveau et de la Moelle, INSERM U1127, CNRS UMR7225, Sorbonne Universités - UPMC Université Paris VI UMR_S1127, Paris, France
| | - T Popa
- APHP Department of Genetics, Groupe Hospitalier Pitié-Salpêtrière, Institut du Cerveau et de la Moelle, INSERM U1127, CNRS UMR7225, Sorbonne Universités - UPMC Université Paris VI UMR_S1127, Paris, France
| | - J-C Lamy
- APHP Department of Genetics, Groupe Hospitalier Pitié-Salpêtrière, Institut du Cerveau et de la Moelle, INSERM U1127, CNRS UMR7225, Sorbonne Universités - UPMC Université Paris VI UMR_S1127, Paris, France
| | - O Odish
- Department of Neurology, Leiden University Medical Centre, 2300RC Leiden, The Netherlands
| | - B R Leavitt
- Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, 950 West 28th Avenue, Vancouver, BC V5Z 4H4, Canada
| | - A Durr
- APHP Department of Genetics, Groupe Hospitalier Pitié-Salpêtrière, Institut du Cerveau et de la Moelle, INSERM U1127, CNRS UMR7225, Sorbonne Universités - UPMC Université Paris VI UMR_S1127, Paris, France
| | - R A C Roos
- Department of Neurology, Leiden University Medical Centre, 2300RC Leiden, The Netherlands
| | - S J Tabrizi
- Huntington's Disease Research Centre, UCL Institute of Neurology, London, UK
| | - J C Rothwell
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, UK
| | - L A Boyd
- Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada
| | - M Orth
- Department of Neurology, Ulm University Hospital, Ulm, Germany.
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21
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Santibanez S, Hübschen JM, Ben Mamou MC, Muscat M, Brown KE, Myers R, Donoso Mantke O, Zeichhardt H, Brockmann D, Shulga SV, Muller CP, O'Connor PM, Mulders MN, Mankertz A. Molecular surveillance of measles and rubella in the WHO European Region: new challenges in the elimination phase. Clin Microbiol Infect 2017; 23:516-523. [PMID: 28712666 DOI: 10.1016/j.cmi.2017.06.030] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [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: 04/05/2017] [Revised: 06/14/2017] [Accepted: 06/15/2017] [Indexed: 01/24/2023]
Abstract
BACKGROUND The WHO European Region (EUR) has adopted the goal of eliminating measles and rubella but individual countries perform differently in achieving this goal. Measles virus spread across the EUR by mobile groups has recently led to large outbreaks in the insufficiently vaccinated resident population. As an instrument for monitoring the elimination process and verifying the interruption of endemic virus transmission, molecular surveillance has to provide valid and representative data. Irrespective of the country's specific situation, it is required to ensure the functionality of the laboratory surveillance that is supported by the WHO Global Measles and Rubella Laboratory Network. AIMS To investigate whether the molecular surveillance in the EUR is adequate for the challenges in the elimination phase, we addressed the quality assurance of molecular data, the continuity and intensity of molecular monitoring, and the analysis of transmission chains. SOURCES Published articles, the molecular External Quality Assessment Programme of the WHO, the Centralized Information System for Infectious Diseases of the WHO EUR and the WHO Measles and Rubella Nucleotide Surveillance databases served as information sources. CONTENT Molecular proficiency testing conducted by the WHO in 2016 has shown that the expertise for measles and rubella virus genotyping exists in all parts of the EUR. The analysis of surveillance data reported nationally to the WHO in 2013-2016 has revealed some countries with outbreaks but not sufficiently representative molecular data. Long-lasting supranational MV transmission chains were identified. IMPLICATIONS A more systematic molecular monitoring and recording of the transmission pattern for the whole EUR could help to create a meaningful picture of the elimination process.
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Affiliation(s)
- S Santibanez
- WHO European Regional Reference Laboratory for Measles and Rubella, Robert Koch-Institut, Berlin, Germany.
| | - J M Hübschen
- WHO European Regional Reference Laboratory for Measles and Rubella, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette and Laboratoire National de Santé, Dudelange, Luxembourg
| | - M C Ben Mamou
- Vaccine-preventable Diseases and Immunization, WHO Regional Office for Europe, Copenhagen, Denmark
| | - M Muscat
- Vaccine-preventable Diseases and Immunization, WHO Regional Office for Europe, Copenhagen, Denmark
| | - K E Brown
- WHO Global Specialized Laboratory for Measles and Rubella, Virus Reference Department, Public Health England, London, UK
| | - R Myers
- WHO Global Specialized Laboratory for Measles and Rubella, Virus Reference Department, Public Health England, London, UK
| | - O Donoso Mantke
- INSTAND e.V. - Gesellschaft zur Förderung der Qualitätssicherung in medizinischen Laboratorien e.V., Düsseldorf, Germany
| | - H Zeichhardt
- INSTAND e.V. - Gesellschaft zur Förderung der Qualitätssicherung in medizinischen Laboratorien e.V., Düsseldorf, Germany; Institut für Virologie, Campus Benjamin Franklin, Charité - Universitätsmedizin Berlin, Germany; Institut für Qualitätssicherung in der Virusdiagnostik - IQVD, Berlin, Germany
| | - D Brockmann
- Epidemiological Modelling of Infectious Diseases, Robert Koch-Institut, Berlin, Germany; Institute for Theoretical Biology, Department of Biology, Humboldt University of Berlin, Berlin, Germany
| | - S V Shulga
- WHO European Regional Reference Laboratory for Measles and Rubella, Gabrichevsky Research Institute for Epidemiology and Microbiology, Moscow, Russia
| | - C P Muller
- WHO European Regional Reference Laboratory for Measles and Rubella, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette and Laboratoire National de Santé, Dudelange, Luxembourg
| | - P M O'Connor
- Vaccine-preventable Diseases and Immunization, WHO Regional Office for Europe, Copenhagen, Denmark
| | - M N Mulders
- Department of Immunization, Vaccines, and Biologicals, World Health Organization, Geneva, Switzerland
| | - A Mankertz
- WHO European Regional Reference Laboratory for Measles and Rubella, Robert Koch-Institut, Berlin, Germany
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22
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Neva JL, Brown KE, Mang CS, Francisco BA, Boyd LA. An acute bout of exercise modulates both intracortical and interhemispheric excitability. Eur J Neurosci 2017; 45:1343-1355. [PMID: 28370664 DOI: 10.1111/ejn.13569] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 03/23/2017] [Accepted: 03/24/2017] [Indexed: 11/28/2022]
Abstract
Primary motor cortex (M1) excitability is modulated following a single session of cycling exercise. Specifically, short-interval intracortical inhibition and intracortical facilitation are altered following a session of cycling, suggesting that exercise affects the excitability of varied cortical circuits. Yet we do not know whether a session of exercise also impacts the excitability of interhemispheric circuits between, and other intracortical circuits within, M1. Here we present two experiments designed to address this gap in knowledge. In experiment 1, single and paired pulse transcranial magnetic stimulation (TMS) were used to measure intracortical circuits including, short-interval intracortical facilitation (SICF) tested at 1.1, 1.5, 2.7, 3.1 and 4.5 ms interstimulus intervals (ISIs), contralateral silent period (CSP) and interhemispheric interactions by measuring transcallosal inhibition (TCI) recorded from the abductor pollicus brevis muscles. All circuits were assessed bilaterally pre and two time points post (immediately, 30 min) moderate intensity lower limb cycling. SICF was enhanced in the left hemisphere after exercise at the 1.5 ms ISI. Also, CSP was shortened and TCI decreased bilaterally after exercise. In Experiment 2, corticospinal and spinal excitability were tested before and after exercise to investigate the locus of the effects found in Experiment 1. Exercise did not impact motor-evoked potential recruitment curves, Hoffman reflex or V-wave amplitudes. These results suggest that a session of exercise decreases intracortical and interhemispheric inhibition and increases facilitation in multiple circuits within M1, without concurrently altering spinal excitability. These findings have implications for developing exercise strategies designed to potentiate M1 plasticity and skill learning in healthy and clinical populations.
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Affiliation(s)
- J L Neva
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, 212-2177 Westbrook Mall, Vancouver, BC, V6T 1Z3, Canada
| | - K E Brown
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, 212-2177 Westbrook Mall, Vancouver, BC, V6T 1Z3, Canada
| | - C S Mang
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, 212-2177 Westbrook Mall, Vancouver, BC, V6T 1Z3, Canada
| | - B A Francisco
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, 212-2177 Westbrook Mall, Vancouver, BC, V6T 1Z3, Canada
| | - L A Boyd
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, 212-2177 Westbrook Mall, Vancouver, BC, V6T 1Z3, Canada
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23
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Hübschen JM, Bork SM, Brown KE, Mankertz A, Santibanez S, Ben Mamou M, Mulders MN, Muller CP. Challenges of measles and rubella laboratory diagnostic in the era of elimination. Clin Microbiol Infect 2017; 23:511-515. [PMID: 28412379 DOI: 10.1016/j.cmi.2017.04.009] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 04/03/2017] [Accepted: 04/05/2017] [Indexed: 11/26/2022]
Abstract
The Member States of the WHO European Region adopted the goal of measles and rubella elimination more than 10 years ago, but so far only 21 of 53 countries have reached this target. Laboratory investigation of suspected cases is essential to support disease elimination efforts. Therefore, WHO maintains a network of accredited laboratories providing high-quality testing. Laboratory investigation heavily relies on specific IgM serology and increasingly on virus detection by reverse transcription (RT)-PCR, but other methods such as IgG avidity testing and genetic characterization of virus strains have gained in importance. In elimination settings, often few samples from suspected cases are available for testing, but testing proficiency must be maintained. The predictive value of an IgM-positive result decreases and other rash-fever disease aetiologies become more important. In addition, cases with a rash after measles/rubella vaccination or with mild disease after waning of vaccine-induced antibodies are seen more often. Thus, it is necessary to perform comprehensive and potentially time-consuming and costly investigations of every suspected case using quality-controlled laboratory methods. At the same time rapid feedback to public health officers is required for timely interventions. The introduction of new laboratory methods for comprehensive case investigations requires training of staff under the supervision of WHO-accredited reference laboratories and the definition of appropriate test algorithms. Clinical, laboratory, and epidemiological data are essential for final case classification and investigation of chains of transmission in the endgame of measles and rubella elimination.
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Affiliation(s)
- J M Hübschen
- WHO European Regional Reference Laboratory for Measles and Rubella, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette and Laboratoire National de Santé, Dudelange, Luxembourg
| | - S M Bork
- WHO European Regional Reference Laboratory for Measles and Rubella, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette and Laboratoire National de Santé, Dudelange, Luxembourg
| | - K E Brown
- WHO Global Specialized Laboratory for Measles and Rubella, Virus Reference Department, Public Health England, London, UK
| | - A Mankertz
- WHO European Regional Reference Laboratory for Measles and Rubella, Robert Koch Institute, Berlin, Germany
| | - S Santibanez
- WHO European Regional Reference Laboratory for Measles and Rubella, Robert Koch Institute, Berlin, Germany
| | - M Ben Mamou
- Vaccine-Preventable Diseases and Immunization, WHO Regional Office for Europe, Copenhagen, Denmark
| | - M N Mulders
- Expanded Programme on Immunization, Department of Immunization, Vaccines, and Biologicals, WHO, Geneva, Switzerland
| | - C P Muller
- WHO European Regional Reference Laboratory for Measles and Rubella, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette and Laboratoire National de Santé, Dudelange, Luxembourg.
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24
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Brown KE, Newby K, Caley M, Danahay A, Kehal I. Pilot evaluation of a web-based intervention targeting sexual health service access. Health Educ Res 2016; 31:273-282. [PMID: 26928566 DOI: 10.1093/her/cyw003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 02/03/2016] [Indexed: 06/05/2023]
Abstract
Sexual health service access is fundamental to good sexual health, yet interventions designed to address this have rarely been implemented or evaluated. In this article, pilot evaluation findings for a targeted public health behavior change intervention, delivered via a website and web-app, aiming to increase uptake of sexual health services among 13-19-year olds are reported. A pre-post questionnaire-based design was used. Matched baseline and follow-up data were identified from 148 respondents aged 13-18 years. Outcome measures were self-reported service access, self-reported intention to access services and beliefs about services and service access identified through needs analysis. Objective service access data provided by local sexual health services were also analyzed. Analysis suggests the intervention had a significant positive effect on psychological barriers to and antecedents of service access among females. Males, who reported greater confidence in service access compared with females, significantly increased service access by time 2 follow-up. Available objective service access data support the assertion that the intervention may have led to increases in service access. There is real promise for this novel digital intervention. Further evaluation is planned as the model is licensed to and rolled out by other local authorities in the United Kingdom.
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Affiliation(s)
- K E Brown
- Centre for Technology Enabled Health Research, Faculty of Health & Life Sciences, Coventry University, Priory Street, Coventry CV1 5FB, UK and Public Health Warwickshire, Warwickshire County Council, Barrack Street, Warwick CV34 4SX, UK
| | - K Newby
- Centre for Technology Enabled Health Research, Faculty of Health & Life Sciences, Coventry University, Priory Street, Coventry CV1 5FB, UK and
| | - M Caley
- Public Health Warwickshire, Warwickshire County Council, Barrack Street, Warwick CV34 4SX, UK
| | - A Danahay
- Public Health Warwickshire, Warwickshire County Council, Barrack Street, Warwick CV34 4SX, UK
| | - I Kehal
- Centre for Technology Enabled Health Research, Faculty of Health & Life Sciences, Coventry University, Priory Street, Coventry CV1 5FB, UK and
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25
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Neva JL, Lakhani B, Brown KE, Wadden KP, Mang CS, Ledwell NHM, Borich MR, Vavasour IM, Laule C, Traboulsee AL, MacKay AL, Boyd LA. Multiple measures of corticospinal excitability are associated with clinical features of multiple sclerosis. Behav Brain Res 2016; 297:187-95. [PMID: 26467603 PMCID: PMC4904787 DOI: 10.1016/j.bbr.2015.10.015] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [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: 07/28/2015] [Revised: 09/04/2015] [Accepted: 10/05/2015] [Indexed: 10/22/2022]
Abstract
In individuals with multiple sclerosis (MS), transcranial magnetic stimulation (TMS) may be employed to assess the integrity of corticospinal system and provides a potential surrogate biomarker of disability. The purpose of this study was to provide a comprehensive examination of the relationship between multiple measures corticospinal excitability and clinical disability in MS (expanded disability status scale (EDSS)). Bilateral corticospinal excitability was assessed using motor evoked potential (MEP) input-output (IO) curves, cortical silent period (CSP), short-interval intracortical inhibition (SICI), intracortical facilitation (ICF) and transcallosal inhibition (TCI) in 26 individuals with MS and 11 healthy controls. Measures of corticospinal excitability were compared between individuals with MS and controls. We evaluated the relationship(s) between age and clinical demographics such as age at MS onset (AO), disease duration (DD) and clinical disability (EDSS) with measures of corticospinal excitability. Corticospinal excitability thresholds were higher, MEP latency and CSP onset delayed and MEP durations prolonged in individuals with MS compared to controls. Age, DD and EDSS correlated with corticospinal excitability thresholds. Also, TCI duration and the linear slope of the MEP amplitude IO curve correlated with EDSS. Hierarchical regression modeling demonstrated that combining multiple TMS-based measures of corticospinal excitability accounted for unique variance in clinical disability (EDSS) beyond that of clinical demographics (AO, DD). Our results indicate that multiple TMS-based measures of corticospinal and interhemispheric excitability provide insights into the potential neural mechanisms associated with clinical disability in MS. These findings may aid in the clinical evaluation, disease monitoring and prediction of disability in MS.
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Affiliation(s)
- J L Neva
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.
| | - B Lakhani
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - K E Brown
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - K P Wadden
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - C S Mang
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - N H M Ledwell
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - M R Borich
- Division of Physical Therapy, Department of Rehabilitation Medicine, School of Medicine, Emory University, Atlanta, GA, USA
| | - I M Vavasour
- Department of Radiology, The University of British Columbia, Vancouver, BC, Canada
| | - C Laule
- Department of Radiology, The University of British Columbia, Vancouver, BC, Canada; Department of Pathology & Laboratory Medicine, The University of British Columbia, Vancouver, BC, Canada
| | - A L Traboulsee
- Division of Neurology, Department of Medicine, Faculty of Medicine, The University of British Columbia, Vancouver, BC, Canada
| | - A L MacKay
- Department of Radiology, The University of British Columbia, Vancouver, BC, Canada; Department of Physics & Astronomy, The University of British Columbia, Vancouver, BC, Canada
| | - L A Boyd
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
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26
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Thompson CI, Ellis J, Galiano M, Ramsay M, Brown KE, Zambon M. Detection of influenza A(H3N2) virus in children with suspected mumps during winter 2014/15 in England. ACTA ACUST UNITED AC 2015; 20. [PMID: 26290428 DOI: 10.2807/1560-7917.es2015.20.31.21203] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Influenza A(H3N2) virus was detected in oral fluid from 16/107 children (aged 2 to 12 years) with a clinical diagnosis of mumps, who were sampled between December 2014 and February 2015 in England, during the peak of the 2014/15 influenza season. Sequence analysis of an A(H3N2) virus from a child with suspected mumps showed the virus was similar to other circulating A(H3N2) viruses detected in winter 2014/15, which were antigenically drifted from the A(H3N2) vaccine strain.
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Affiliation(s)
- C I Thompson
- Public Health England, Virus Reference Department, Colindale, London, United Kingdom
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27
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Brown KE, Neva JL, Ledwell NM, Boyd LA. Use of transcranial magnetic stimulation in the treatment of selected movement disorders. Degener Neurol Neuromuscul Dis 2014; 4:133-151. [PMID: 32669907 PMCID: PMC7337234 DOI: 10.2147/dnnd.s70079] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [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: 03/05/2014] [Accepted: 04/23/2014] [Indexed: 11/23/2022] Open
Abstract
Transcranial magnetic stimulation (TMS) is a valuable technique for assessing the underlying neurophysiology associated with various neuropathologies, and is a unique tool for establishing potential neural mechanisms responsible for disease progression. Recently, repetitive TMS (rTMS) has been advanced as a potential therapeutic technique to treat selected neurologic disorders. In healthy individuals, rTMS can induce changes in cortical excitability. Therefore, targeting specific cortical areas affected by movement disorders theoretically may alter symptomology. This review discusses the evidence for the efficacy of rTMS in Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, and multiple sclerosis. It is hoped that gaining a more thorough understanding of the timing and parameters of rTMS in individuals with neurodegenerative disorders may advance both clinical care and research into the most effective uses of this technology.
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Affiliation(s)
| | - Jason L Neva
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | | | - Lara A Boyd
- Graduate Program in Rehabilitation Science.,Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
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28
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29
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Wallace LM, Brown KE, Hilton S. Planning for, implementing and assessing the impact of health promotion and behaviour change interventions: a way forward for health psychologists. Health Psychol Rev 2013; 8:8-33. [PMID: 25053005 DOI: 10.1080/17437199.2013.775629] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Researchers in the field of health psychology have increasingly been involved in translating a body of knowledge about psychological factors associated with health-relevant behaviours, into the development and evaluation of interventions that seek to apply that knowledge. In this paper we argue that a changing economic and political climate, and the strong behavioural contribution to disease morbidity and mortality in developed nations, requires health psychologists to plan more rigorously for, and communicate more effectively, about how health promotion, social cognition and behaviour change interventions will have impact and be increasingly embedded into health services or health promotion activity. We explain academic and wider socio-economic uses of 'impact' in health services research. We describe the relationship between impact and dissemination, and impact as distinct from, but often used interchangeably with the terms 'implementation', 'knowledge transfer' and 'knowledge translation' (KT). The evidence for establishing impact is emergent. We therefore draw on a number of impact planning and KT frameworks, with reference to two self- management interventions, to describe a framework that we hope will support health psychologists in embedding impact planning and execution in research. We illustrate this further in an on-line annexe with reference to one of our own interventions, Mums-and-MS (see Supplemental Material).
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Affiliation(s)
- L M Wallace
- a Applied Research Centre for Health & Lifestyle Interventions , Coventry University , Coventry CV1 5FB , UK
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30
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Pebody RG, Chand MA, Thomas HL, Green HK, Boddington NL, Carvalho C, Brown CS, Anderson SR, Rooney C, Crawley-Boevey E, Irwin DJ, Aarons E, Tong C, Newsholme W, Price N, Langrish C, Tucker D, Zhao H, Phin N, Crofts J, Bermingham A, Gilgunn-Jones E, Brown KE, Evans B, Catchpole M, Watson JM. The United Kingdom public health response to an imported laboratory confirmed case of a novel coronavirus in September 2012. Euro Surveill 2012. [DOI: 10.2807/ese.17.40.20292-en] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
On 22 September 2012, a novel coronavirus, very closely related to that from a fatal case in Saudi Arabia three months previously, was detected in a previously well adult transferred to intensive care in London from Qatar with severe respiratory illness. Strict respiratory isolation was instituted. Ten days after last exposure, none of 64 close contacts had developed severe disease, with 13 of 64 reporting mild respiratory symptoms. The novel coronavirus was not detected in 10 of 10 symptomatic contacts tested.
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Affiliation(s)
- R G Pebody
- Health Protection Agency (HPA), London, United Kingdom
| | - M A Chand
- Health Protection Agency (HPA), London, United Kingdom
| | - H L Thomas
- European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control, (ECDC), Stockholm, Sweden
- Field Epidemiology Training Programme (FETP), Health Protection Agency, London, United Kingdom
- Health Protection Agency (HPA), London, United Kingdom
| | - H K Green
- Health Protection Agency (HPA), London, United Kingdom
| | | | - C Carvalho
- European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control, (ECDC), Stockholm, Sweden
- Health Protection Agency (HPA), London, United Kingdom
| | - C S Brown
- Centre for Clinical Infection and Diagnostics Research, King’s College London, London, England
- Health Protection Agency (HPA), London, United Kingdom
| | - S R Anderson
- Health Protection Agency (HPA), London, United Kingdom
| | - C Rooney
- Health Protection Agency (HPA), London, United Kingdom
| | | | - D J Irwin
- Health Protection Agency (HPA), London, United Kingdom
| | - E Aarons
- Guy’s and St Thomas’ NHS Foundation Trust and King’s Health Partners, London, United Kingdom
| | - C Tong
- Guy’s and St Thomas’ NHS Foundation Trust and King’s Health Partners, London, United Kingdom
| | - W Newsholme
- Guy’s and St Thomas’ NHS Foundation Trust and King’s Health Partners, London, United Kingdom
| | - N Price
- Guy’s and St Thomas’ NHS Foundation Trust and King’s Health Partners, London, United Kingdom
| | - C Langrish
- Guy’s and St Thomas’ NHS Foundation Trust and King’s Health Partners, London, United Kingdom
| | - D Tucker
- Guy’s and St Thomas’ NHS Foundation Trust and King’s Health Partners, London, United Kingdom
| | - H Zhao
- Health Protection Agency (HPA), London, United Kingdom
| | - N Phin
- Health Protection Agency (HPA), London, United Kingdom
| | - J Crofts
- Health Protection Agency (HPA), London, United Kingdom
| | - A Bermingham
- Health Protection Agency (HPA), London, United Kingdom
| | | | - K E Brown
- Health Protection Agency (HPA), London, United Kingdom
| | - B Evans
- Health Protection Agency (HPA), London, United Kingdom
| | - M Catchpole
- Health Protection Agency (HPA), London, United Kingdom
| | - J M Watson
- Health Protection Agency (HPA), London, United Kingdom
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31
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Pebody RG, Chand MA, Thomas HL, Green HK, Boddington NL, Carvalho C, Brown CS, Anderson SR, Rooney C, Crawley-Boevey E, Irwin DJ, Aarons E, Tong C, Newsholme W, Price N, Langrish C, Tucker D, Zhao H, Phin N, Crofts J, Bermingham A, Gilgunn-Jones E, Brown KE, Evans B, Catchpole M, Watson JM. The United Kingdom public health response to an imported laboratory confirmed case of a novel coronavirus in September 2012. Euro Surveill 2012; 17:20292. [PMID: 23078799] [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: 06/01/2023] Open
Abstract
On 22 September 2012, a novel coronavirus, very closely related to that from a fatal case in Saudi Arabia three months previously, was detected in a previously well adult transferred to intensive care in London from Qatar with severe respiratory illness. Strict respiratory isolation was instituted. Ten days after last exposure, none of 64 close contacts had developed severe disease, with 13 of 64 reporting mild respiratory symptoms. The novel coronavirus was not detected in 10 of 10 symptomatic contacts tested.
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Affiliation(s)
- R G Pebody
- Health Protection Agency (HPA), London, UK.
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32
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Brown KE, Abraham C, Joshi P, Wallace LM. Sexual health professionals' evaluations of a prototype computer-based contraceptive planning intervention for adolescents: implications for practice. Sex Health 2012; 9:341-8. [PMID: 22877593 DOI: 10.1071/sh11042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2011] [Accepted: 01/20/2012] [Indexed: 11/23/2022]
Abstract
BACKGROUND This paper aims to demonstrate how an online planning intervention to enhance contraceptive and condom use among adolescents was viewed by sexual health professionals. It identifies feedback that has facilitated improvement of the intervention both in terms of potential effectiveness and sustainability in practice. The data illustrate how professionals' feedback can enhance intervention development. METHOD Ten practitioners (two male; eight female) representing a range of roles in sexual health education and healthcare were given electronic copies of the prototype intervention. Interviews were conducted to elicit feedback. Transcripts of the interviews were subjected to thematic analysis. RESULTS Practitioners provided positive feedback about the intervention content, use of on-line media, the validity of planning techniques and the inclusion of males in contraceptive planning. Issues with rapport building, trust, privacy, motivation, and time and resources were raised, however, and the promotion of condom carrying was contentious. CONCLUSIONS Professionals' feedback provided scope for developing the intervention to meet practitioners' concerns, thus enhancing likely feasibility and acceptability in practice. Ways in which particular feedback was generalisable to wider theory-based and online intervention development are explored. Some responses indicated that health practitioners would benefit from training to embed theory-based interventions into sexual health education and healthcare.
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Affiliation(s)
- K E Brown
- Coventry University, Coventry, CV1 5FB, UK.
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Maple PAC, Breuer J, Quinlivan M, Kafatos G, Brown KE. Comparison of a commercial Varicella Zoster glycoprotein IgG enzyme immunoassay with a reference time resolved fluorescence immunoassay (VZV TRFIA) for measuring VZV IgG in sera from pregnant women, sera sent for confirmatory testing and pre and post vOka vaccination sera from healthcare workers. J Clin Virol 2012; 53:201-7. [PMID: 22261123 DOI: 10.1016/j.jcv.2011.12.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [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: 10/20/2011] [Revised: 12/08/2011] [Accepted: 12/09/2011] [Indexed: 01/30/2023]
Abstract
BACKGROUND Recently, a commercial, standardised VZV IgG glycoprotein EIA, Binding Site VaccZyme™VZV glycoprotein IgG low level EIA (VaccZyme™EIA) has become available. The VaccZyme™EIA is more robust and user friendly than the reference VZV time-resolved fluorescence immunoassay (VZV TRFIA). OBJECTIVES To assess the usefulness of the VaccZyme™EIA in the diagnostic laboratory by comparing VZV IgG levels generated by both assays on serum panels representing, non-vaccinated, and vOka vaccinated populations. STUDY DESIGN Sera from non-vaccinated individuals were tested; 248 from pregnant women, 117 from various patient groups referred to the Virus Reference Department for confirmatory VZV IgG testing and 102 from healthcare workers enrolled in a study (ROVE) of antibody/IgG response to vOka. From the ROVE study, 282 post vaccination sera were tested; 108 and 101 collected at six weeks post first and second doses of vOka, respectively, and 73 collected at 18 month follow-up. RESULTS Sensitivities and specificities (equivocals treated as negatives) of the VaccZyme™EIA for sera from pregnant women were 97.8% (95% CI: [94.6%, 99.4%]) and 96.8% (95% CI: [89.0%, 99.6%]), respectively, and for sera referred for confirmatory testing were 81.2% (95% CI: [71.2%, 88.8%]) and 96.9% (95% CI: [83.8%, 99.9%]), respectively, and for ROVE baseline sera were 54.2% (95% CI: [32.8%, 74.4%]) and 100% (95% CI: [95.4%, 100.0%]), respectively. For the post vOka serum panels sensitivities of the VaccZyme™EIA ranged from 65.3% (95% CI: [50.4%, 78.3%]) to 80.4% (95% CI: [71.1%, 87.8%]). Specificities were all 100%. Correlation with VZV TRFIA was high and agreement varied between the serum panels tested. CONCLUSIONS VaccZyme™EIA is recommended for detecting VZV IgG in sera from non-vaccinated populations; however, caution is advised when measuring post vOka VZV IgG levels.
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Affiliation(s)
- P A C Maple
- Virus Reference Department, Health Protection Agency, Microbiology Services, Colindale, London, UK.
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Brown KE, Mulders MN, Freymuth F, Santibanez S, Mosquera MM, Cordey S, Beirnes J, Shulga S, Myers R, Featherstone D. Appearance of a novel measles G3 strain in multiple European countries within a two month period, 2010. Euro Surveill 2011. [DOI: 10.2807/ese.16.17.19852-en] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
During late 2010, a previously unrecognised strain of measles genotype G3 virus was identified in five different European countries by the World Health Organization Measles and Rubella Laboratory Network. Apart from one, none had a travel history to south-east Asia, the usual source of G3 viruses, although epidemiological links could be established between some of the cases. This case series illustrates the value of genotyping and sequencing in tracking measles infections, and identifying otherwise unrecognised chains of transmission.
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Affiliation(s)
- K E Brown
- Virus Reference Department, World Health Organization Global Specialised Laboratory for Measles and Rubella, Health Protection Agency - Colindale, London, United Kingdom
| | - M N Mulders
- World Health Organization Regional Office for Europe, Copenhagen, Denmark
| | - F Freymuth
- Centre National de Référence de la Rougeole et des Paramyxoviridae Respiratoires (National Reference Centre for measles and respiratory Paramyxoviridae), Laboratoire de virologie humaine et moléculaire (Laboratory of human and molecular virology), Centre Hospitalier Universitaire de Caen, France
| | - S Santibanez
- National Reference Centre Measles, Mumps, Rubella, Regional Reference Laboratory WHO EURO, Robert Koch Institute, Berlin, Germany
| | - M M Mosquera
- Centro Nacional de Microbiología (National Microbiology Centre), Instituto de Salud Carlos III, Madrid, Spain
| | - S Cordey
- Swiss National Reference Centre for Emerging Viral Diseases, Division of Infectious Diseases, University of Geneva Hospitals, Geneva, Switzerland
| | - J Beirnes
- Viral Exanthemata National Microbiology Laboratory, Winnipeg, Canada
| | - S Shulga
- World Health Organization Regional Reference Laboratory, European Region, Moscow, Russian Federation
| | - R Myers
- Virus Reference Department, World Health Organization Global Specialised Laboratory for Measles and Rubella, Health Protection Agency - Colindale, London, United Kingdom
| | - D Featherstone
- Expanded Programme on Immunization, Department of Immunization, Vaccines and Biologicals, World Health Organization, Geneva, Switzerland
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Brown KE, Mulders MN, Freymuth F, Santibanez S, Mosquera MM, Cordey S, Beirnes J, Shulga S, Myers R, Featherstone D. Appearance of a novel measles G3 strain in multiple European countries within a two month period, 2010. Euro Surveill 2011; 16:19852. [PMID: 21543045] [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: 05/30/2023] Open
Abstract
During late 2010, a previously unrecognised strain of measles genotype G3 virus was identified in five different European countries by the World Health Organization Measles and Rubella Laboratory Network.Apart from one, none had a travel history to south-east Asia, the usual source of G3 viruses, although epidemiological links could be established between some of the cases. This case series illustrates the value of genotyping and sequencing in tracking measles infections, and identifying otherwise unrecognised chains of transmission.
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Affiliation(s)
- K E Brown
- Virus Reference Department, World Health Organization Global Specialised Laboratory for Measles and Rubella, Health Protection Agency - Colindale, London, United Kingdom.
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McDonald SLR, Maple PAC, Andrews N, Brown KE, Ayres KL, Scott FT, Al Bassam M, Gershon AA, Steinberg SP, Breuer J. Evaluation of the time resolved fluorescence immunoassay (TRFIA) for the detection of varicella zoster virus (VZV) antibodies following vaccination of healthcare workers. J Virol Methods 2010; 172:60-5. [PMID: 21192976 DOI: 10.1016/j.jviromet.2010.12.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Revised: 12/16/2010] [Accepted: 12/22/2010] [Indexed: 10/18/2022]
Abstract
Determination of varicella zoster virus (VZV) immunity in healthcare workers without a history of chickenpox is important for identifying those in need of vOka vaccination. Post immunisation, healthcare workers in the UK who work with high risk patients are tested for seroconversion. To assess the performance of the time-resolved fluorescence immunoassay (TRFIA) for the detection of antibody in vaccinated as well as unvaccinated individuals, a cut-off was first calculated. VZV-IgG specific avidity and titres six weeks after the first dose of vaccine were used to identify subjects with pre-existing immunity among a cohort of 110 healthcare workers. Those with high avidity (≥ 60%) were considered to have previous immunity to VZV and those with low or equivocal avidity (<60%) were considered naive. The former had antibody levels ≥ 400 mIU/mL and latter had levels < 400 mIU/mL. Comparison of the baseline values of the naive and immune groups allowed the estimation of a TRFIA cut-off value of > 130 mIU/mL which best discriminated between the two groups and this was confirmed by ROC analysis. Using this value, the sensitivity and specificity of TRFIA cut-off were 90% (95% CI 79-96), and 78% (95% CI 61-90) respectively in this population. A subset of samples tested by the gold standard Fluorescence Antibody to Membrane Antigen (FAMA) test showed 84% (54/64) agreement with TRFIA.
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Affiliation(s)
- S L R McDonald
- Centre of Immunology and Infectious Diseases, Blizard Institute of Cell and Molecular Science, Bart's and the London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark St, Whitechapel, London E12AT, UK
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Winchester SA, Brown KE. A woman with suspected subacute sclerosing panencephalitis (SSPE). J Clin Virol 2010; 50:93-5. [PMID: 20951637 DOI: 10.1016/j.jcv.2010.09.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Accepted: 09/08/2010] [Indexed: 10/18/2022]
Affiliation(s)
- S A Winchester
- Virus Reference Department, Centre for Infections, Health Protection Agency, 61 Colindale Avenue, London NW9 5EQ, United Kingdom
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Cramp P, Derksen FJ, Stick JA, Nickels FA, Brown KE, Robinson P, Robinson NE. Effect of ventriculectomy versus ventriculocordectomy on upper airway noise in draught horses with recurrent laryngeal neuropathy. Equine Vet J 2010; 41:729-34. [PMID: 20095218 DOI: 10.2746/042516409x434099] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [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
REASONS FOR PERFORMING STUDY Little is known about the efficacy of bilateral ventriculectomy (VE) or bilateral ventriculocordectomy (VCE) in draught horses. OBJECTIVES To compare the effect of VE and VCE on upper airway noise in draught horses with recurrent laryngeal neuropathy (RLN) by use of quantitative sound analysis techniques. HYPOTHESIS In competitive draught horses with grade 4 RLN, VE and VCE reduce upper airway noise during exercise, but VCE is more effective. METHODS Thirty competitive hitch or pulling draught horses with grade 4 RLN were evaluated for upper airway sound during exercise. Respiratory rate (RR), inspiratory (Ti) and expiratory time (Te), the ratio between Ti and Te (Ti/Te), inspiratory (Sli) and expiratory sound levels (Sle), the ratio between Sli and Sle (Sli/Sle), and peak sound intensity of the second formant (F2) were calculated. Eleven horses were treated with VE and 19 with VCE. After 90 days of voice and physical rest and 30 days of work, the horses returned for post operative upper airway sound evaluation and resting videoendoscopy. RESULTS VE significantly reduced Ti/Te, Sli, Sli/Sle and the sound intensity of F2. Respiratory rate, Ti, Te and Sle were unaffected by VE. VCE significantly reduced Ti/Te, Ti, Te, Sli, Sli/Sle and the sound intensity of F2, while RR and Sle were unaffected. The reduction in sound intensity of F2 following VCE was significantly greater than following VE. After VE and VCE, 7/11 (64%) and 15/18 (83%) owners, respectively, concluded that the surgery improved upper airway sound in their horses sufficiently for successful competition. CONCLUSIONS VE and VCE significantly reduce upper airway noise and indices of airway obstruction in draught horses with RLN, but VCE is more effective than VE. The procedures have few post operative complications. POTENTIAL RELEVANCE VCE is recommended as the preferred treatment for RLN in draught horses. Further studies are required to evaluate the longevity of the procedure's results.
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Affiliation(s)
- P Cramp
- Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, Michigan 48824-1314, USA
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Abstract
REASONS FOR PERFORMING STUDY Perineural analgesics are used for lameness diagnosis but the duration of effect, knowledge of which would provide valuable information when performing subsequent blocks, is unknown. OBJECTIVE To evaluate the duration of a palmar digital nerve block using force plate measurements. METHODS Ten horses diagnosed with unilateral navicular syndrome were trotted at range of 3 +/- 0.15 m/sec over a force plate to record ground reaction forces for 5 trials of each forelimb. Data were recorded before nerve block, and then at 15 mins, 1, 2 and 24 h post nerve block. RESULTS Before nerve block, peak vertical force (mean +/- s.e.) was significantly higher in the contralateral forelimb (CL = 5345 +/- 188 N) than in the lame forelimb (L = 4256 +/- 204 N; P<0.05). At 15 mins post nerve block there was no significant difference between the 2 forelimbs (CL = 5140 +/- 184 N; L = 5126 +/- 129 N), and this remained the case for 1 h. By 2 h, the mean score for the lame leg had decreased (L = 4642 +/- 182 N) but was still greater than preblock. By 24 h, vertical forces had returned to preblock values. CONCLUSIONS The palmar digital nerve block was fully effective between 15 mins and 1 h. The analgesic effect began to subside between 1 and 2 h but sufficient analgesia persisted to affect gait characteristics beyond 2 h. POTENTIAL RELEVANCE When using a palmar digital nerve block, it is important to perform lameness evaluations between 15 mins and 1 h to be sure of effective nerve blockade.
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Affiliation(s)
- L A Bidwell
- Large Animal Clinical Sciences, Michigan State University, East Lansing, Michigan 48824, USA
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Abstract
Measles virus causes an acute infection characterised by rash and fever. Measles infection is preventable by vaccination, but remains a significant cause of childhood mortality in the developing world with an estimated number of approximately 242,000 deaths by measles in 2006 [1].
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Affiliation(s)
- S Gnaneshan
- Centre for Infections, Health Protection Agency London, United Kingdom
| | - K E Brown
- Centre for Infections, Health Protection Agency London, United Kingdom
| | - J Green
- Centre for Infections, Health Protection Agency London, United Kingdom
| | - D W Brown
- Centre for Infections, Health Protection Agency London, United Kingdom
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Gnaneshan S, Brown KE, Green J, Brown DW. On-line global/WHO-European regional measles nucleotide surveillance. Euro Surveill 2008; 13:18861. [PMID: 18761979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Affiliation(s)
- S Gnaneshan
- Centre for Infections, Health Protection Agency London, United Kingdom.
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Campbell H, Andrews N, Brown KE, Miller E. Review of the effect of measles vaccination on the epidemiology of SSPE. Int J Epidemiol 2007; 36:1334-48. [DOI: 10.1093/ije/dym207] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Kayali Z, Tan S, Shinkunas L, Voigt M, LaBrecque DR, Stapleton JT, Brown KE, Schmidt WN. Risk factors for hepatitis C fibrosis: a prospective study of United States veterans compared with nonveterans. J Viral Hepat 2007; 14:11-21. [PMID: 17212639 DOI: 10.1111/j.1365-2893.2006.00764.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Chronic hepatitis C virus (HCV) infection causes cirrhosis in many infected patients; however, a better understanding of the risk factors for fibrosis progression in high HCV prevalence groups such as US veterans is needed. We wished to compare the demographic, clinical characteristics, and independent variables that influence fibrosis in US veterans vs nonveterans with chronic HCV. HCV-seropositive US veterans (n = 459) and nonveterans (n = 395) prospectively completed a detailed medical, social and occupational questionnaire. Clinical factors for progressive liver disease were compared between veterans and nonveterans and fibrosis stage assessed on liver biopsies (168 veterans and 208 nonveterans). Using polychotomous logistic regression, fibrosis was analysed as both a progressive and categorical outcome to determine independent risk factors for both patient groups. Although veterans were significantly older and had higher lifetime alcohol consumption than nonveterans, their median fibrosis scores did not differ from nonveterans. By univariate analysis, alanine aminotransferase, necroinflammatory activity (NIA), and cryoglobulin positivity were associated with fibrosis in veterans and nonveterans (P < 0.05, all comparisons), whereas steatosis was associated with fibrosis only in nonveterans (P < 0.0001). By multivariate analysis, NIA was an independent risk factor for fibrosis in both groups (P < 0.01). However, fibrosis in nonveterans was also independently associated with steatosis, significant alcohol consumption and age (P < 0.04, all comparisons). Independent risk factors for fibrosis vary among high HCV prevalence groups such as veterans when compared with nonveterans. Understanding specific patient cohort effects is important for determining independent risk factors for disease progression in chronic HCV infection.
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Affiliation(s)
- Z Kayali
- Division of Gastroenterology and Hepatology, Liver Transplant Institute, Loma Linda University, Loma Linda, CA, USA
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Lee WM, Brown KE, Young NS, Dawson GJ, Schlauder GG, Gutierrez RA, Fontana R, Rossaro L, Davern T, Lalani E. Brief report: no evidence for parvovirus B19 or hepatitis E virus as a cause of acute liver failure. Dig Dis Sci 2006; 51:1712-5. [PMID: 16964546 DOI: 10.1007/s10620-005-9061-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2005] [Accepted: 09/16/2005] [Indexed: 12/09/2022]
Abstract
Viral hepatitis A and B are known to cause acute liver failure. While nearly 20% of acute liver failure cases are of indeterminate etiology, screening for other viruses has not been uniformly performed. We looked for evidence for parvovirus B19 and hepatitis E virus in sera from U.S. acute liver failure patients. For B19, 78 patients' sera, including 34 with indeterminate etiology, were evaluated by DNA dot-blot hybridization, reverse transcription polymerase chain reaction, and enzyme-linked immunosorbent assay for immunoglobin G and M antibodies; none showed evidence for infection.
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Affiliation(s)
- W M Lee
- Division of Digestive and Liver Diseases, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-8887, USA.
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Brown KE, Broadhurst KA, Mathahs MM, Kladney RD, Fimmel CJ, Srivastava SK, Brunt EM. Immunodetection of aldose reductase in normal and diseased human liver. Histol Histopathol 2005; 20:429-36. [PMID: 15736047 DOI: 10.14670/hh-20.429] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Aldose reductase is an NADPH-dependent aldo-keto reductase best known as the rate-limiting enzyme of the polyol pathway that is implicated in the complications of diabetes. Aldose reductase appears to be involved in a variety of disease states other than diabetes, presumably due to its ability to catalyze the reduction of a broad spectrum of aldehydes, including some cytotoxic products of lipid peroxidation. Although the data regarding expression of aldose reductase in normal liver are conflicting, prior studies have suggested that the enzyme may be induced in diseased liver. The goal of these studies was to characterize expression of aldose reductase in normal and diseased human liver, using RT-PCR, Western analysis and immunohistochemistry. Aldose reductase transcripts and protein were detected at low levels in control human livers. In contrast, levels of aldose reductase mRNA and protein were increased in chronically diseased human livers. Immunohistochemistry demonstrated localization of aldose reductase in sinusoidal lining cells; dual immunofluorescence confocal microscopy with the macrophage marker, CD68, confirmed that the aldose reductase-positive sinusoidal lining cells were Kupffer cells. Abundant aldose reductase-positive, CD68-positive cells were present in the fibrous septa of cirrhotic livers, accounting for the increase in immunoreactive aldose reductase in diseased livers. Immunostaining of human lung, spleen and lymph node revealed that macrophages in those tissues also express aldose reductase. These data are the first to demonstrate that aldose reductase is expressed by human macrophages in various tissues and suggest that this enzyme may play a role in immune or inflammatory processes.
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Affiliation(s)
- K E Brown
- Iowa City Veterans Administration Medical Center, Iowa City, IA, USA.
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Brown KE. Variants of B19. Dev Biol (Basel) 2004; 118:71-7. [PMID: 15645675] [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: 05/01/2023]
Abstract
The human parvovirus B19 (B19), the only known human pathogenic parvovirus, was discovered in 1975. Like other parvoviruses it is a small (22-24 nm diameter) non-enveloped icosahedral virus, with a single-stranded genome. As part of its life history it replicates to high titre in the bone marrow, and in acute infection high titres of infectious virus are present in the peripheral blood. Parvovirus B19 is therefore not an uncommon 'contaminant' of blood and blood products. In addition the lack of lipid membrane envelope renders parvoviruses insensitive to solvent detergents, and the small genome confers relative resistance to heat and gamma irradiation. Many medical reviews have been written on the molecular biology, clinical features, approaches to diagnosis and management, and these should be consulted for more information. This review will give an overview of the biology of parvovirus B19 infection, and the more recently described variants of parvovirus B19.
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Affiliation(s)
- K E Brown
- Hematology Branch, National Heart, Lung and Blood Institute, Bethesda, MD 20892, USA.
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47
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Maciejewski JP, Follmann D, Nakamura R, Saunthararajah Y, Rivera CE, Simonis T, Brown KE, Barrett JA, Young NS. Increased frequency of HLA-DR2 in patients with paroxysmal nocturnal hemoglobinuria and the PNH/aplastic anemia syndrome. Blood 2001; 98:3513-9. [PMID: 11739151 DOI: 10.1182/blood.v98.13.3513] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Many autoimmune diseases are associated with HLA alleles, and such a relationship also has been reported for aplastic anemia (AA). AA and paroxysmal nocturnal hemoglobinuria (PNH) are related clinically, and glycophosphoinositol (GPI)-anchored protein (AP)-deficient cells can be found in many patients with AA. The hypothesis was considered that expansion of a PNH clone may be a marker of immune-mediated disease and its association with HLA alleles was examined. The study involved patients with a primary diagnosis of AA, patients with myelodysplastic syndrome (MDS), and patients with primary PNH. Tests of proportions were used to compare allelic frequencies. For patients with a PNH clone (defined by the presence of GPI-AP-deficient granulocytes), regardless of clinical manifestations, there was a higher than normal incidence of HLA-DR2 (58% versus 28%; z = 4.05). The increased presence of HLA-DR2 was found in all frankly hemolytic PNH and in PNH associated with bone marrow failure (AA/PNH and MDS/PNH). HLA-DR2 was more frequent in AA/PNH (56%) than in AA without a PNH clone (37%; z = 3.36). Analysis of a second cohort of patients with bone marrow failure treated with immunosuppression showed that HLA-DR2 was associated with a hematologic response (50% of responders versus 34% of nonresponders; z = 2.69). Both the presence of HLA-DR2 and the PNH clone were independent predictors of response but the size of PNH clone did not correlate with improvement in blood count. The results suggest that clonal expansion of GPI-AP-deficient cells is linked to HLA and likely related to an immune mechanism.
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Affiliation(s)
- J P Maciejewski
- Hematology Branch and Office of Biostatistics Research, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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Abstract
Oxidative damage to tissue proteins has been implicated in the pathogenesis of liver disease, but the mechanisms that promote oxidation in vivo are unclear. Hydrogen peroxide is transformed into an array of potentially damaging reactants by the heme protein myeloperoxidase. This proinflammatory enzyme is expressed by circulating neutrophils and monocytes but is generally thought to be absent from tissue macrophages. To determine whether myeloperoxidase is present in Kupffer cells, the fixed-tissue macrophages of liver, Western blot analysis, and immunohistochemistry were performed. Two different antibodies monospecific for myeloperoxidase identified a 60-kd protein, the predicted molecular mass of myeloperoxidase, in human liver extracts. Immunostaining detected the enzyme in sinusoidal lining cells of normal and diseased human livers. Immunofluorescence confocal microscopy demonstrated co-localization of myeloperoxidase and CD68, a monocyte/macrophage marker, in sinusoidal lining cells. Numerous myeloperoxidase-expressing cells were also evident in the fibrous septa of cirrhotic livers. Immunostaining with an antibody to proteins modified by hypochlorous acid, a characteristic product of the enzyme, indicated that myeloperoxidase is enzymatically active in cases of acute liver injury and cirrhosis. These findings identify myeloperoxidase as a component of human Kupffer cells. Oxidative damage resulting from the action of myeloperoxidase may contribute to acute liver injury and hepatic fibrogenesis.
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Affiliation(s)
- K E Brown
- John Cochran Veteran's Administration Medical Center, St. Louis, Missouri, USA.
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49
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Abstract
A novel flavivirus, GB virus C (GBV-C)/hepatitis G virus (HGV), has been detected in chronic liver disease patients. It is known that the viral RNA can be detected in approximately 5% of American blood donors. However, the implications for liver disease and the sites of virus replication remain unknown. Possible sites of virus replication were studied by using cell lines and/or primary cells derived from human lymphoid cells, myeloid cells, hepatocytes and endothelial cells. RNA was detected by virus strand-specific RT-PCR and GBV-C/HGV antigen was detected with a rabbit polyclonal anti-E2 (envelope 2) antibody by Western blot analysis. Negative-strand RNA, representative of replicating virus, was detected in lymphoid and megakaryocytoid cell lines and primary vascular endothelial cells. In addition, an increase in virus titre over time was demonstrated and viral antigen was detected, and virus could be passaged to infect fresh cells. However, viral RNA or antigen could not be detected in any of the hepatocyte lines tested. These results indicate that the replication site of GBV-C/HGV is not primarily in hepatocytes and that detection of replicating virus in hepatic tissue may reflect virus replication in haematopoietic cells and/or vascular endothelial cells present in the liver.
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Affiliation(s)
- K E Brown
- Virus Discovery Group, Hematology Branch, National Heart, Lung and Blood Institute, Bethesda, MD 20892, USA
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Magnusson MK, Meade KE, Brown KE, Arthur DC, Krueger LA, Barrett AJ, Dunbar CE. Rabaptin-5 is a novel fusion partner to platelet-derived growth factor beta receptor in chronic myelomonocytic leukemia. Blood 2001; 98:2518-25. [PMID: 11588050 DOI: 10.1182/blood.v98.8.2518] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Chromosomal translocations involving the platelet-derived growth factor beta receptor (PDGFbetaR) gene have been reported in some patients with chronic myelomonocytic leukemia (CMML). The resultant fusion proteins have constitutive PDGFbetaR tyrosine kinase activity, but the partner genes previously reported (tel, Huntingtin interacting protein 1 [HIP-1], H4/D10S170) have poorly understood roles in the oncogenic activity of the fusion proteins. A novel PDGFbetaR fusion protein has been characterized in a patient with CMML and an acquired t(5;17)(q33;p13). Southern blot analysis on patient leukemia cells demonstrated involvement of the PDGFbetaR gene. Using 5' rapid amplification of complementary DNA ends-polymerase chain reaction (RACE-PCR) on patient RNA, rabaptin-5 was identified as a novel partner fused in-frame to the PDGFbetaR gene. The new fusion protein includes more than 85% of the native Rabaptin-5 fused to the transmembrane and intracellular tyrosine kinase domains of the PDGFbetaR. Transduction with a retroviral vector expressing rabaptin-5/PDGFbetaR transformed the hematopoietic cell line Ba/F3 to growth factor independence and caused a fatal myeloproliferative disease in mice. Rabaptin-5 is a well-studied protein shown to be an essential and rate-limiting component of early endosomal fusion through interaction with the Ras family GTPases Rab5 and Rab4. The fusion protein includes 3 of 4 coiled-coil domains (involved in homodimerization of native rabaptin-5), 2 caspase-3 cleavage sites, and a binding site for the tumor suppressor gene tuberin (tuberous sclerosis complex-2). Early endosomal transport is critical in regulation of various growth factor receptors, through ligand-induced clathrin-mediated endocytosis, and thus this new fusion protein links together 2 important pathways of growth regulation.
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MESH Headings
- Adult
- Animals
- Bone Marrow/pathology
- Cell Line
- Cloning, Molecular
- Humans
- In Situ Hybridization, Fluorescence
- Karyotyping
- Leukemia, Myelomonocytic, Chronic/blood
- Leukemia, Myelomonocytic, Chronic/genetics
- Leukemia, Myelomonocytic, Chronic/pathology
- Male
- Membrane Proteins/genetics
- Mice
- Mice, Inbred BALB C
- Oncogene Proteins, Fusion/genetics
- Receptor, Platelet-Derived Growth Factor beta/genetics
- Recombinant Fusion Proteins/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Transfection
- Translocation, Genetic
- Vesicular Transport Proteins
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Affiliation(s)
- M K Magnusson
- Hematology Branch, National Heart, Lung, and Blood Institute, and Laboratory of Pathology, Division of Clinical Sciences, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
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