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Farooq B, Russell AE, Howe LD, Herbert A, Smith ADAC, Fisher HL, Baldwin JR, Arseneault L, Danese A, Mars B. The relationship between type, timing and duration of exposure to adverse childhood experiences and adolescent self-harm and depression: findings from three UK prospective population-based cohorts. J Child Psychol Psychiatry 2024. [PMID: 38613494 DOI: 10.1111/jcpp.13986] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/14/2024] [Indexed: 04/15/2024]
Abstract
BACKGROUND Adverse childhood experiences (ACEs) are well-established risk factors for self-harm and depression. However, despite their high comorbidity, there has been little focus on the impact of developmental timing and the duration of exposure to ACEs on co-occurring self-harm and depression. METHODS Data were utilised from over 22,000 children and adolescents participating in three UK cohorts, followed up longitudinally for 14-18 years: the Avon Longitudinal Study of Parents and Children (ALSPAC), the Millennium Cohort Study (MCS) and the Environmental Risk (E-Risk) Longitudinal Twin Study. Multinomial logistic regression models estimated associations between each ACE type and a four-category outcome: no self-harm or depression, self-harm alone, depression alone and self-harm with co-occurring depression. A structured life course modelling approach was used to examine whether the accumulation (duration) of exposure to each ACE, or a critical period (timing of ACEs) had the strongest effects on self-harm and depression in adolescence. RESULTS The majority of ACEs were associated with co-occurring self-harm and depression, with consistent findings across cohorts. The importance of timing and duration of ACEs differed across ACEs and across cohorts. For parental mental health problems, longer duration of exposure was strongly associated with co-occurring self-harm and depression in both ALSPAC (adjusted OR: 1.18, 95% CI: 1.10-1.25) and MCS (1.18, 1.11-1.26) cohorts. For other ACEs in ALSPAC, exposure in middle childhood was most strongly associated with co-occurring self-harm and depression, and ACE occurrence in early childhood and adolescence was more important in the MCS. CONCLUSIONS Efforts to mitigate the impact of ACEs should start in early life with continued support throughout childhood, to prevent long-term exposure to ACEs contributing to risk of self-harm and depression in adolescence.
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Affiliation(s)
- Bushra Farooq
- Centre for Academic Mental Health, Population Health Sciences, University of Bristol Medical School, Bristol, UK
| | - Abigail E Russell
- Children and Young People's Mental Health Research Collaboration, University of Exeter Medical School, Exeter, UK
| | - Laura D Howe
- MRC Integrative Epidemiology Unit, Population Health Sciences, University of Bristol Medical School, Bristol, UK
| | - Annie Herbert
- MRC Integrative Epidemiology Unit, Population Health Sciences, University of Bristol Medical School, Bristol, UK
| | - Andrew D A C Smith
- Mathematics and Statistics Research Group, University of the West of England, Bristol, UK
| | - Helen L Fisher
- Social, Genetic & Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
- ESRC Centre for Society and Mental Health, King's College London, London, UK
| | - Jessie R Baldwin
- Social, Genetic & Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
- Division of Psychology and Language Sciences, Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Louise Arseneault
- Mathematics and Statistics Research Group, University of the West of England, Bristol, UK
| | - Andrea Danese
- Social, Genetic & Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
- Department of Child and Adolescent Psychiatry, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
- National and Specialist CAMHS Clinic for Trauma, Anxiety, and Depression, South London and Maudsley NHS Foundation Trust, London, UK
| | - Becky Mars
- Centre for Academic Mental Health, Population Health Sciences, University of Bristol Medical School, Bristol, UK
- National Institute for Health and Care Research, Biomedical Research Centre, Bristol, UK
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Curtin EL, Widnall E, Dodd S, Limmer M, Simmonds R, Russell AE, Kaley A, Kidger J. Exploring mechanisms and contexts in a Peer Education Project to improve mental health literacy in schools in England: a qualitative realist evaluation. Health Educ Res 2024; 39:40-54. [PMID: 37490030 PMCID: PMC10805377 DOI: 10.1093/her/cyad026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 06/26/2023] [Accepted: 06/27/2023] [Indexed: 07/26/2023]
Abstract
Poor adolescent mental health calls for universal prevention. The Mental Health Foundation's 'Peer Education Project' equips older students ('peer educators') to teach younger students ('peer learners') about mental health. The peer-led lessons cover defining good and bad mental health, risk and protective factors, self-care, help-seeking and looking after one another. While previous pre-post evaluations have suggested effectiveness, the mechanisms through which the intervention improves mental health literacy remain unclear. We purposively recruited seven secondary schools across England from 2020 to 2022 and collected data through five observations, 12 staff interviews and 15 student focus groups (totalling 134 students; 46 peer educators aged 14-18 years and 88 peer learners aged 11-13 years). Our realist analysis adopted retroductive logic, intertwining deductive and inductive approaches to test the initial programme theory against insights arising from the data. We developed Context-Mechanisms-Outcome configurations related to four themes: (i) modelling behaviours and forming supportive relationships, (ii) relevant and appropriate content, (iii) peer educators feeling empowered and (iV) a school culture that prioritises mental health support. Our refined programme theory highlights key mechanisms, contexts conducive to achieving the outcomes and ways to improve training, recruitment and delivery to maximise effectiveness for similar peer-led initiatives.
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Affiliation(s)
- E L Curtin
- Department of Population Health, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - E Widnall
- Population Health Sciences, Bristol Medical School, University of Bristol, Canynge Hall, Bristol BS8 2PS, UK
| | - S Dodd
- Division of Health Research, Lancaster University, Hazelrigg Lane, Lancaster LA1 4YW, UK
| | - M Limmer
- Division of Health Research, Lancaster University, Hazelrigg Lane, Lancaster LA1 4YW, UK
| | - R Simmonds
- Mental Health Foundation, Long Lane, London SE1 4PD, UK
| | - A E Russell
- College of Medicine and Health, University of Exeter, Heavitree Road, Exeter EX1 2LU, UK
| | - A Kaley
- Division of Health Research, Lancaster University, Hazelrigg Lane, Lancaster LA1 4YW, UK
- School of Health and Social Care, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - J Kidger
- Population Health Sciences, Bristol Medical School, University of Bristol, Canynge Hall, Bristol BS8 2PS, UK
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Engler-Chiurazzi EB, Russell AE, Povroznik JM, McDonald KO, Porter KN, Wang DS, Hammock J, Billig BK, Felton CC, Yilmaz A, Schreurs BG, O'Callaghan JD, Zwezdaryk KJ, Simpkins JW. Intermittent systemic exposure to lipopolysaccharide-induced inflammation disrupts hippocampal long-term potentiation and impairs cognition in aging male mice. Brain Behav Immun 2023; 108:279-291. [PMID: 36549577 PMCID: PMC10019559 DOI: 10.1016/j.bbi.2022.12.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [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] [Received: 06/17/2022] [Revised: 12/13/2022] [Accepted: 12/14/2022] [Indexed: 12/24/2022] Open
Abstract
Age-related cognitive decline, a common component of the brain aging process, is associated with significant impairment in daily functioning and quality of life among geriatric adults. While the complexity of mechanisms underlying cognitive aging are still being elucidated, microbial exposure and the multifactorial inflammatory cascades associated with systemic infections are emerging as potential drivers of neurological senescence. The negative cognitive and neurobiological consequences of a single pathogen-associated inflammatory experience, such as that modeled through treatment with lipopolysaccharide (LPS), are well documented. Yet, the brain aging impacts of repeated, intermittent inflammatory challenges are less well studied. To extend the emerging literature assessing the impact of infection burden on cognitive function among normally aging mice, here, we repeatedly exposed adult mice to intermittent LPS challenges during the aging period. Male 10-month-old C57BL6 mice were systemically administered escalating doses of LPS once every two weeks for 2.5 months. We evaluated cognitive consequences using the non-spatial step-through inhibitory avoidance task, and both spatial working and reference memory versions of the Morris water maze. We also probed several potential mechanisms, including cortical and hippocampal cytokine/chemokine gene expression, as well as hippocampal neuronal function via extracellular field potential recordings. Though there was limited evidence for an ongoing inflammatory state in cortex and hippocampus, we observed impaired learning and memory and a disruption of hippocampal long-term potentiation. These data suggest that a history of intermittent exposure to LPS-induced inflammation is associated with subtle but significantly impaired cognition among normally aging mice. The broader impact of these findings may have important implications for standard of care involving infections in aging individuals or populations at-risk for dementia.
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Affiliation(s)
- E B Engler-Chiurazzi
- Clinical Neuroscience Research Center, Department of Neurosurgery, Tulane Brain Institute, Tulane University, New Orleans, LA 70114, USA; Center for Basic and Translational Stroke Research, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA; Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA.
| | - A E Russell
- Center for Basic and Translational Stroke Research, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA; Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA; Department of Biology, School of Science, Penn State Erie, The Behrend College, Erie, PA 16563, USA; Magee Women's Research Institute, Allied Member, Pittsburgh, PA 15213, USA
| | - J M Povroznik
- Center for Basic and Translational Stroke Research, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA; Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA
| | - K O McDonald
- Clinical Neuroscience Research Center, Department of Neurosurgery, Tulane Brain Institute, Tulane University, New Orleans, LA 70114, USA
| | - K N Porter
- Center for Basic and Translational Stroke Research, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA
| | - D S Wang
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA
| | - J Hammock
- Center for Basic and Translational Stroke Research, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA
| | - B K Billig
- Health Effects Laboratory Division, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA
| | - C C Felton
- Health Effects Laboratory Division, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA
| | - A Yilmaz
- Health Effects Laboratory Division, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA
| | - B G Schreurs
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA
| | - J D O'Callaghan
- Health Effects Laboratory Division, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA
| | - K J Zwezdaryk
- Department of Microbiology and Immunology, Tulane Brain Institute, Tulane University, New Orleans, LA 70114, USA
| | - J W Simpkins
- Center for Basic and Translational Stroke Research, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA; Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA
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Orri M, Russell AE, Mars B, Turecki G, Gunnell D, Heron J, Tremblay RE, Boivin M, Nuyt AM, Côté SM, Geoffroy MC. Perinatal adversity profiles and suicide attempt in adolescence and young adulthood: longitudinal analyses from two 20-year birth cohort studies. Psychol Med 2022; 52:1255-1267. [PMID: 33019954 DOI: 10.1017/s0033291720002974] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND We aimed to identify groups of children presenting distinct perinatal adversity profiles and test the association between profiles and later risk of suicide attempt. METHODS Data were from the Québec Longitudinal Study of Child Development (QLSCD, N = 1623), and the Avon Longitudinal Study of Parents and Children (ALSPAC, N = 5734). Exposures to 32 perinatal adversities (e.g. fetal, obstetric, psychosocial, and parental psychopathology) were modeled using latent class analysis, and associations with a self-reported suicide attempt by age 20 were investigated with logistic regression. We investigated to what extent childhood emotional and behavioral problems, victimization, and cognition explained the associations. RESULTS In both cohorts, we identified five profiles: No perinatal risk, Poor fetal growth, Socioeconomic adversity, Delivery complications, Parental mental health problems (ALSPAC only). Compared to children with No perinatal risk, children in the Poor fetal growth (pooled estimate QLSCD-ALSPAC, OR 1.89, 95% CI 1.04-3.44), Socioeconomic adversity (pooled-OR 1.42, 95% CI 1.08-1.85), and Parental mental health problems (OR 1.74, 95% CI 1.27-2.40), but not Delivery complications, profiles were more likely to attempt suicide. The proportion of this effect mediated by the putative mediators was larger for the Socioeconomic adversity profile compared to the others. CONCLUSIONS Perinatal adversities associated with suicide attempt cluster in distinct profiles. Suicide prevention may begin early in life and requires a multidisciplinary approach targeting a constellation of factors from different domains (psychiatric, obstetric, socioeconomic), rather than a single factor, to effectively reduce suicide vulnerability. The way these factors cluster together also determined the pathways leading to a suicide attempt, which can guide decision-making on personalized suicide prevention strategies.
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Affiliation(s)
- Massimiliano Orri
- Department of Psychiatry, McGill Group for Suicide Studies, Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada
- Bordeaux Population Health Research Centre, Inserm U1219, University of Bordeaux, Bordeaux, France
| | - Abigail E Russell
- Centre for Academic Mental Health, Population Health Sciences, University of Bristol Medical School, Bristol, UK
- National Institute of Health Research Biomedical Research Centre, University Hospitals Bristol NHS Foundation Trust, University of Bristol, Bristol, UK (Mars, Gunnell)
| | - Becky Mars
- Centre for Academic Mental Health, Population Health Sciences, University of Bristol Medical School, Bristol, UK
- National Institute of Health Research Biomedical Research Centre, University Hospitals Bristol NHS Foundation Trust, University of Bristol, Bristol, UK (Mars, Gunnell)
| | - Gustavo Turecki
- Department of Psychiatry, McGill Group for Suicide Studies, Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada
| | - David Gunnell
- Centre for Academic Mental Health, Population Health Sciences, University of Bristol Medical School, Bristol, UK
- National Institute of Health Research Biomedical Research Centre, University Hospitals Bristol NHS Foundation Trust, University of Bristol, Bristol, UK (Mars, Gunnell)
| | - Jon Heron
- Centre for Academic Mental Health, Population Health Sciences, University of Bristol Medical School, Bristol, UK
| | - Richard E Tremblay
- School of Public Health, Physiotherapy and Sports Science, University College Dublin, Dublin, Ireland (Tremblay)
- Departments of Pediatrics and Psychology, University of Montréal, Montreal, QC, Canada (Tremblay)
| | - Michel Boivin
- School of Psychology, Université Laval, Québec City, Québec, Canada (Boivin)
| | - Anne-Monique Nuyt
- Department of Pediatrics, Centre Hospitalier Universitaire Sainte-Justine Research Center, University of Montreal, Montreal, QC, Canada (Nuyt)
| | - Sylvana M Côté
- Department of Social and Preventive Medicine, University of Montreal, Montreal, QC, Canada (Côté)
| | - Marie-Claude Geoffroy
- Department of Educational and Counselling Psychology, McGill University, Montreal, QC, Canada (Geoffroy)
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5
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Russell AE, Moore D, Sanders A, Dunn B, Hayes R, Kidger J, Sonuga-Barke E, Pfiffner L, Ford T. Synthesising the existing evidence for non-pharmacological interventions targeting outcomes relevant to young people with ADHD in the school setting: systematic review protocol. Syst Rev 2022; 11:28. [PMID: 35168685 PMCID: PMC8848797 DOI: 10.1186/s13643-022-01902-x] [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] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 02/07/2022] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Children and adolescents with attention-deficit/hyperactivity disorder (ADHD) have impairing levels of difficulty paying attention, impulsive behaviour and/or hyperactivity. ADHD causes extensive difficulties for young people at school, and as a result these children are at high risk for a wide range of poor outcomes. We ultimately aim to develop a flexible, modular 'toolkit' of evidence-based strategies that can be delivered by primary school staff to improve the school environment and experience for children with ADHD; the purpose of this review is to identify and quantify the evidence-base for potential intervention components. This protocol sets out our plans to systematically identify non-pharmacological interventions that target outcomes that have been reported to be of importance to key stakeholders (ADHD symptoms, organisation skills, executive-global- and classroom-functioning, quality of life, self-esteem and conflict with teachers and peers). We plan to link promising individual intervention components to measured outcomes, and synthesise the evidence of effectiveness for each outcome. METHODS A systematic search for studies published from the year 2000 that target the outcomes of interest in children and young people aged 3-12 will be conducted. Titles and abstracts will be screened using prioritisation software, and then full texts of potentially eligible studies will be screened. Systematic reviews, RCTs, non-randomised and case-series studies are eligible designs. Synthesis will vary by the type of evidence available, potentially including a review of reviews, meta-analysis and narrative synthesis. Heterogeneity of studies meta-analysed will be assessed, along with publication bias. Intervention mapping will be applied to understand potential behaviour change mechanisms for promising intervention components. DISCUSSION This review will highlight interventions that appear to effectively ameliorate negative outcomes that are of importance for people with ADHD, parents, school staff and experts. Components of intervention design and features that are associated with effective change in the outcome will be delineated and used to inform the development of a 'toolkit' of non-pharmacological strategies that school staff can use to improve the primary school experience for children with ADHD. TRIAL REGISTRATION PROSPERO number CRD42021233924.
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Affiliation(s)
- Abigail E Russell
- University of Exeter College of Medicine and Health, South Cloisters, St Luke's Campus, Exeter, EX1 2LU, UK.
| | - Darren Moore
- University of Exeter College of Medicine and Health, South Cloisters, St Luke's Campus, Exeter, EX1 2LU, UK
| | - Amy Sanders
- University of Exeter College of Medicine and Health, South Cloisters, St Luke's Campus, Exeter, EX1 2LU, UK
| | - Barnaby Dunn
- University of Exeter College of Medicine and Health, South Cloisters, St Luke's Campus, Exeter, EX1 2LU, UK
| | - Rachel Hayes
- University of Exeter College of Medicine and Health, South Cloisters, St Luke's Campus, Exeter, EX1 2LU, UK
| | | | | | - Linda Pfiffner
- University of California San Francisco, San Francisco, USA
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Leach AS, Hack J, Amboage M, Diaz-Moreno S, Huang H, Cullen PL, Wilding M, Magliocca E, Miller TS, Howard CA, Brett DJL, Shearing PR, McMillan PF, Russell AE, Jervis R. A novel fuel cell design for operandoenergy-dispersive x-ray absorption measurements. J Phys Condens Matter 2021; 33:314002. [PMID: 34030140 DOI: 10.1088/1361-648x/ac0476] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 05/24/2021] [Indexed: 06/12/2023]
Abstract
A polymer electrolyte fuel cell has been designed to allowoperandox-ray absorption spectroscopy (XAS) measurements of catalysts. The cell has been developed to operate under standard fuel cell conditions, with elevated temperatures and humidification of the gas-phase reactants, both of which greatly impact the catalyst utilisation. X-ray windows in the endplates of the cell facilitate collection of XAS spectra during fuel cell operation while maintaining good compression in the area of measurement. Results of polarisation curves and cyclic voltammograms showed that theoperandocell performs well as a fuel cell, while also providing XAS data of suitable quality for robust XANES analysis. The cell has produced comparable XAS results when performing a cyclic voltammogram to an establishedin situcell when measuring the Pt LIII edge. Similar trends of Pt oxidation, and reduction of the formed Pt oxide, have been presented with a time resolution of 5 s for each spectrum, paving the way for time-resolved spectral measurements of fuel cell catalysts in a fully-operating fuel cell.
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Affiliation(s)
- A S Leach
- Electrochemical Innovation Lab, Department of Chemical Engineering, UCL, London WC1E 7JE, United Kingdom
| | - J Hack
- Electrochemical Innovation Lab, Department of Chemical Engineering, UCL, London WC1E 7JE, United Kingdom
| | - M Amboage
- Diamond Light Source, Didcot, Oxon, OX11 0DE, United Kingdom
| | - S Diaz-Moreno
- Diamond Light Source, Didcot, Oxon, OX11 0DE, United Kingdom
| | - H Huang
- School of Chemistry, University of Southampton, University Road, Southampton SO17 1BJ, United Kingdom
| | - P L Cullen
- Electrochemical Innovation Lab, Department of Chemical Engineering, UCL, London WC1E 7JE, United Kingdom
- School of Engineering and Materials Science (SEMS) and Material Research Institute, Queen Mary University of London, London, E1 4NS, United Kingdom
| | - M Wilding
- UK Catalysis Hub, Research Complex at Harwell, Harwell Campus, OX11 0FA, United Kingdom
| | - E Magliocca
- Electrochemical Innovation Lab, Department of Chemical Engineering, UCL, London WC1E 7JE, United Kingdom
| | - T S Miller
- Electrochemical Innovation Lab, Department of Chemical Engineering, UCL, London WC1E 7JE, United Kingdom
| | - C A Howard
- Department of Physics & Astronomy, University College London, London WC1E 6BT, United Kingdom
| | - D J L Brett
- Electrochemical Innovation Lab, Department of Chemical Engineering, UCL, London WC1E 7JE, United Kingdom
| | - P R Shearing
- Electrochemical Innovation Lab, Department of Chemical Engineering, UCL, London WC1E 7JE, United Kingdom
| | - P F McMillan
- Department of Chemistry, Christopher Ingold Laboratory, University College London, 20 Gordon St., London WC1H 0AJ, United Kingdom
| | - A E Russell
- School of Chemistry, University of Southampton, University Road, Southampton SO17 1BJ, United Kingdom
| | - R Jervis
- Electrochemical Innovation Lab, Department of Chemical Engineering, UCL, London WC1E 7JE, United Kingdom
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Pavlickova H, Russell AE, Lightman S, McCabe R. Feasibility of salivary cortisol collection in patients and companions attending dementia diagnostic meetings in memory clinics. BMC Res Notes 2021; 14:30. [PMID: 33478564 PMCID: PMC7818922 DOI: 10.1186/s13104-021-05446-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 01/08/2021] [Indexed: 11/24/2022] Open
Abstract
Objectives Receiving a diagnosis of dementia is life-changing for the individual and their companion. The aim of the study was to explore the feasibility of collecting salivary cortisol from patients who are informed if they have dementia and their companions. Patients and companions collected nine saliva samples in three batches: 1–2 weeks before, immediately before, and immediately after the diagnostic meeting. Each batch consisted of three samples taken in the evening, after awaking and 30 mins post-waking. Results 22.7% (N = 10) of 44 invited patients and nine companions agreed, with 18.2% patients (N = 8) and 15.9% companions (N = 7) providing samples. Participants found that saliva collection was demanding and disrupted routines. On a purely descriptive level, some indications of an increased cortisol stress response in patients diagnosed with dementia were found in this very small sample. Researchers should expect low recruitment rates in this elderly population. Simpler collection procedures, e.g. pre-labelled packages with date/time, possible omission of morning samples and objective rather than self-report assessment of waking and saliva collection times—using actigraphy wrist-watches bleeps to prompt people at the timepoints and electronic track caps—might improve adherence and improve the accuracy of timepoints when swabs were actually collected.
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Affiliation(s)
- H Pavlickova
- Mental Health Research Group, University of Exeter Medical School, University of Exeter, Exeter, UK
| | - A E Russell
- Mental Health Research Group, University of Exeter Medical School, University of Exeter, Exeter, UK
| | - S Lightman
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, Dorothy Hodgkin Building, University of Bristol, Bristol, BS1 3NY, UK
| | - R McCabe
- School of Health Sciences, City, University of London, 1 Myddelton Street, London, EC1R 1UW, UK.
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Russell AE, Ford T, Russell G. Barriers and predictors of medication use for childhood ADHD: findings from a UK population-representative cohort. Soc Psychiatry Psychiatr Epidemiol 2019; 54:1555-1564. [PMID: 31073627 PMCID: PMC6858474 DOI: 10.1007/s00127-019-01720-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 04/25/2019] [Indexed: 01/23/2023]
Abstract
PURPOSE Little is known about sociodemographic and clinical factors that predict and act as barriers to ADHD medication independently of symptom severity. We examined the proportion of children using medication for ADHD, age of initiation of medication, and predictors of medication use in a population-representative cohort. METHODS Data from the Millennium Cohort Study on child ADHD, medication use for ADHD at age 14 (in 2014-2015) and child, parent and sociodemographic variables were collated. Logistic regression models were used to identify factors that predict medication use for ADHD (the main outcome measure), adjusting for symptom severity at age seven. RESULTS The weighted prevalence of ADHD was 3.97% (N = 11,708). 45.57% of children with ADHD (N = 305) were taking medication. The median age at initiation was 9 years (range 3-14). Male gender (AOR 3.66, 95% CI 1.75, 7.66) and conduct problems at age seven (AOR 1.24 95% CI 1.04, 1.47) and 14 predicted medication use at age 14 after adjusting for symptom severity. CONCLUSIONS Our study is the first to assess predictors of medication whist adjusting for ADHD symptom severity. Girls with ADHD were less likely to be prescribed medication, even when they displayed similar ADHD symptom levels to boys. Conduct problems also predicted medication independently of ADHD symptoms. ADHD may be more often medicated in boys because clinicians may think a prototypical ADHD child is male, and perhaps conduct problems make boys more disruptive in the classroom, leading to boys being more often treated.
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Affiliation(s)
- A E Russell
- Centre for Academic Mental Health, University of Bristol Medical School, Oakfield House, Bristol, BS8 2BN, UK.
| | - T Ford
- University of Exeter Medical School, St Luke's Campus, Exeter, EX1 2LU, UK
| | - G Russell
- University of Exeter Medical School, St Luke's Campus, Exeter, EX1 2LU, UK
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Moore DA, Russell AE, Arnell S, Ford TJ. Educators' experiences of managing students with ADHD: a qualitative study. Child Care Health Dev 2017; 43:489-498. [PMID: 28233330 DOI: 10.1111/cch.12448] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 11/20/2016] [Accepted: 01/08/2017] [Indexed: 01/04/2023]
Abstract
BACKGROUND The symptoms of attention-deficit/hyperactivity disorder are associated with difficulty coping with the social, behavioural and academic components of school. Compared with medication and other non-pharmacological treatment, there is less evidence relating to school-based interventions to support children with ADHD. There is additionally an absence of any research focused on the experiences and practices of educators in the UK around how they work with children who are inattentive, impulsive and hyperactive. METHODS Forty-two educational practitioners from primary, secondary and alternate provision schools in the UK participated in focus groups or individual interviews that explored (1) their experiences of managing students with ADHD in the classroom and (2) factors that helped and hindered them in this endeavour. Transcripts were analysed using thematic analysis. RESULTS Analysis identified six themes: broad strategies, student-centred, inclusive strategies, labelling, medication and relationships. Participants' experiences of managing students with ADHD drew upon a wide range of strategies that typically involved responding to individual needs in an inclusive manner, so individuals with ADHD could access the classroom with their peers. Participants spoke about three factors that helped and hindered managing students with ADHD. Labelling of students with ADHD was reported, with the negative aspects of labelling, such as stigmatization, affecting the classroom. Educators reported mixed experiences regarding the helpfulness of medication; where helpful, it allowed the use of strategies in the classroom. Although students with ADHD were described as having rollercoaster relationships, positive relationships were considered key to the support of children with these difficulties. CONCLUSIONS This study suggests that factors such as attitudes towards ADHD, relationships experienced by students with ADHD and other treatments being delivered need to be carefully considered before strategies are put in place in the classroom. This study supports the need for further work on the implementation of evidence-based school interventions for ADHD.
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Affiliation(s)
- D A Moore
- University of Exeter Medical School, Exeter, UK
| | - A E Russell
- University of Exeter Medical School, Exeter, UK
| | - S Arnell
- Psychology, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - T J Ford
- University of Exeter Medical School, Exeter, UK
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10
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Ford T, Macdiarmid F, Russell AE, Racey D, Goodman R. The predictors of persistent DSM-IV disorders in 3-year follow-ups of the British Child and Adolescent Mental Health Surveys 1999 and 2004. Psychol Med 2017; 47:1126-1137. [PMID: 27995813 DOI: 10.1017/s0033291716003214] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
BACKGROUND The identification of the factors that influence the persistence of psychiatric disorder may assist practitioners to focus on young people who are particularly prone to poor outcomes, but population-based samples of sufficient size are rare. METHOD This secondary analysis combined data from two large, population-based cross-sectional surveys in Great Britain (1999 and 2004) and their respective follow-ups (2002 and 2007), to study homotypic persistence among the 998 school-age children with psychiatric disorder at baseline. Psychiatric disorder was measured using the Development and Well-Being Assessment applying DSM-IV criteria. Factors relating to the child, family, and the severity and type of psychopathology at baseline were analysed using logistic regression. RESULTS Approximately 50% of children with at least one psychiatric disorder were assigned the same diagnostic grouping at 3-year follow-up. Persistent attention-deficit/hyperactivity disorder and anxiety were predicted by poor peer relationship scores. Persistent conduct disorder was predicted by intellectual disability, rented housing, large family size, poor family function and by severer baseline psychopathology scores. CONCLUSIONS Homotypic persistence was predicted by different factors for different groups of psychiatric disorders. Experimental research in clinical samples should explore whether these factors also influence response to interventions.
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Affiliation(s)
- T Ford
- University of Exeter Medical School,Exeter,Devon,UK
| | - F Macdiarmid
- King's College London,Institute of Psychiatry,London,UK
| | - A E Russell
- University of Exeter Medical School,Exeter,Devon,UK
| | - D Racey
- University of Exeter Medical School,Exeter,Devon,UK
| | - R Goodman
- King's College London,Institute of Psychiatry,London,UK
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11
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Brownlow N, Russell AE, Saravanapavan H, Wiesmann M, Murray JM, Manley PW, Dibb NJ. Comparison of nilotinib and imatinib inhibition of FMS receptor signaling, macrophage production and osteoclastogenesis. Leukemia 2007; 22:649-52. [PMID: 17851554 DOI: 10.1038/sj.leu.2404944] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Harvey PJ, Wing LM, Beilby J, Ramsay A, Tonkin AL, Goh SH, Russell AE, Bune AJ, Chalmers JP. Effect of indomethacin on blood pressure control during treatment with nitrendipine. Blood Press 1995; 4:307-12. [PMID: 8535553 DOI: 10.3109/08037059509077612] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
This study tested the hypothesis that treatment with a nonsteroidal anti-inflammatory drug will not alter the hypotensive effect of a dihydropyridine calcium channel antagonist. Fifteen essential hypertensives (ages 58-80 years) had a supine diastolic blood pressure (DBP) < 100 mmHg after 4 weeks monotherapy with nitrendipine 5-20 mg twice daily. They entered a double-blind randomised crossover study in which the addition of indomethacin 25 mg three times daily was compared with placebo in treatment phases each of 4 weeks duration. Subjects were seen weekly and measurements in the last 2 weeks of each phase were compared. Supine blood pressure (mean +/- SE) was higher in the indomethacin phase (158 +/- 4/80 +/- 2) than in the placebo phase (154 +/- 4/76 +/- 3) (p < 0.01 for DBP). In 6/15 (40%) of subjects the increase in supine diastolic blood pressure with indomethacin was > 5 mmHg. Plasma urea was also increased in the indomethacin phase: 7.6 +/- 0.6 mmol/l compared with placebo: 6.3 +/- 0.5 mmol/l (p < 0.001). The study has demonstrated that concurrent treatment with the NSAID indomethacin impairs the blood pressure lowering effect of the dihydropyridine calcium channel antagonist nitrendipine. This increase in blood pressure with indomethacin in subjects treated with nitrendipine may represent either an independent pressor effect of indomethacin or a reduced vasodilator prostanoid contribution to the hypotensive effect of nitrendipine. This blood pressure increase may be sufficient to interfere significantly with clinical blood pressure control in some subjects.
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Affiliation(s)
- P J Harvey
- Department of Clinical Pharmacology, Flinders Medical Centre, Adelaide, S.A., Australia
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15
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Wing LM, Russell AE, Tonkin AL, Bune AJ, West MJ, Chalmers JP. Felodipine, metoprolol and their combination compared with placebo in isolated systolic hypertension in the elderly. Blood Press 1994; 3:82-9. [PMID: 8199723 DOI: 10.3109/08037059409101526] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This study compared with placebo the efficacy and tolerability of optimised doses of felodipine 5-20 mg daily, metoprolol 50-200 mg daily and their combination in subjects 60 years or over with isolated systolic hypertension. The study employed a randomised double-blind crossover design with allocation of treatment order within subjects by Latin squares. For each subject, after a single-blind run-in placebo phase, there were four randomised treatment phases each of six weeks duration, with a dose titration step at three weeks if necessary. Twenty-eight subjects entered the randomised phases of the study and twenty-one completed all four phases--13 male, 8 female (ages: median 71, range 59-85 years). At the end of both the felodipine and metoprolol phases systolic and diastolic pressure were reduced at 2 hours postdose compared with the placebo phase (p < 0.001), the blood pressure reduction with felodipine (-40/-20 mmHg) being greater than that with metoprolol (-15/-9 mmHg) (p < 0.01). Immediately predose (12 hours postdose) there was a persisting reduction of supine systolic blood pressure (-17 mmHg) with felodipine (p < 0.001), but there was no significant effect of metoprolol. At both measurement times the two drugs when in combination had an additive effect on blood pressure. There was a 20% increase in reported symptoms during each of the active treatment phases. Four subjects withdrew during the randomised phases because of probable drug-related adverse events and six subjects required dosage reductions during the felodipine or combination phases.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- L M Wing
- Department of Clinical Pharmacology, Flinders Medical Centre, Bedford Park, Adelaide, Australia
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16
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Wing LM, Russell AE, Tonkin AL, Watts RW, Bune AJ, West MJ, Chalmers JP. Mono- and combination therapy with felodipine or enalapril in elderly patients with systolic hypertension. Blood Press 1994; 3:90-6. [PMID: 8199724 DOI: 10.3109/08037059409101527] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Using a randomised double-blind crossover design with Latin square allocation of treatments in 20 subjects (7 male, 13 female-ages: 61-87 years) with systolic hypertension, we investigated the efficacy and tolerability of once daily felodipine (extended release) 5-20 mg, enalapril 5-20 mg and their combination compared with placebo in four treatment phases each of 6 weeks duration. During each phase, doses were titrated to achieve a predose clinic supine systolic blood pressure of 140 mmHg or to a predetermined maximum dose. In both the felodipine and combination phases, predose supine and standing systolic and diastolic pressures were significantly reduced compared with the placebo phase (decrease in supine pressure: -13/-5 and -18/-7, respectively). Only predose supine diastolic pressure was significantly reduced (-3 mmHg) compared to placebo in the enalapril phase. In combination the effects of the two drugs on predose blood pressure were additive. There was a 40-60% increase in reported symptoms in the felodipine and combination phases compared with the placebo and enalapril phases. Thus, in elderly subjects with systolic hypertension, felodipine effectively reduces blood pressure throughout the dose interval but with vasodilator adverse effects. In contrast, enalapril is well tolerated but is less effective in reducing blood pressure throughout the whole dose interval.
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Affiliation(s)
- L M Wing
- Department of Clinical Pharmacology, Flinders Medical Centre, Bedford Park, Adelaide, Australia
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17
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Russell AE, Russell RE. Cheap thrills. Med J Aust 1993; 158:136. [PMID: 8419758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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18
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Tonkin AL, Wing LM, Russell AE, West MJ, Bune AJ, Morris MJ, Cain MD, Chalmers J. Diltiazem and atenolol in essential hypertension: additivity of effects on blood pressure and cardiac conduction with combination therapy. J Hypertens 1990; 8:1015-9. [PMID: 1963183 DOI: 10.1097/00004872-199011000-00007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In 15 patients with mild to moderate essential hypertension, the effects of diltiazem (120 mg twice daily) were compared with those of atenolol (50 mg once daily), the two drugs in combination, and placebo in a randomized double-blind cross-over study with treatment phases of 4 weeks duration. Blood pressure was reduced in the active treatment phases (supine blood pressure: diltiazem, 172/92 mmHg; atenolol, 172/92 mmHg; diltiazem plus atenolol, 164/88 mmHg; pooled estimate of s.e.m. by analysis of variance = 3/1) compared with placebo (180/101 mmHg). Factorial analysis confirmed fully additive antihypertensive effects of the drugs in combination. The time interval from the beginning of the P wave to the beginning of the QRS complex (P-R interval) was longer during combination therapy (0.184s) compared with either diltiazem (0.175s) or atenolol (0.174s) alone, or placebo (0.164s); s.e.m. by analysis of variance = 0.003. No clinically significant conduction disturbances occurred. Plasma atrial natriuretic peptide was elevated by atenolol but not diltiazem. Thus, in subjects with uncomplicated essential hypertension, diltiazem and atenolol had equal antihypertensive efficacy when used alone, and fully additive effects in combination, on both blood pressure and cardiac conduction.
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Affiliation(s)
- A L Tonkin
- Flinders Medical Centre, Adelaide, South Australia
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19
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Wing LM, Nestel PJ, Chalmers JP, Rouse I, West MJ, Bune AJ, Tonkin AL, Russell AE. Lack of effect of fish oil supplementation on blood pressure in treated hypertensives. J Hypertens 1990; 8:339-43. [PMID: 2160490 DOI: 10.1097/00004872-199004000-00007] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Fish and fish oils have been reported to reduce blood pressure in normotensives and untreated hypertensives. The present study examined the effect of dietary supplementation with fish oil on blood pressure in 20 treated hypertensives with controlled blood pressures who continued their usual antihypertensive drug treatment throughout. A double-blind, randomized crossover design was used, with two phases, each of 8 weeks' duration. In one phase, subjects took fifteen 1 g fish oil capsules (Lipitac; Reckitt and Colman Pharmaceuticals, Sydney, Australia) daily, and in the other, 15 capsules of identical appearance containing 1 g olive oil daily. There was no difference between the treatment phases for any blood pressure parameter, heart rate or body weight, but blood pressure was lower in both phases compared with pretreatment values. The fasting plasma triglyceride concentration was 30% lower in the fish oil phase (P less than 0.001), but there was no difference between the phases for plasma concentrations of total or high-density lipoprotein (HDL) cholesterol. We conclude that, in treated hypertensives with controlled blood pressures, any additional fall in blood pressure produced by dietary supplementation with fish oil is so small that the requirement for antihypertensive drug therapy is unlikely to be reduced.
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Affiliation(s)
- L M Wing
- Hypertension Clinic, Flinders Medical Centre, Bedford Park, Australia
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20
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Russell AE, Smith SA, West MJ, Aylward PE, McRitchie RJ, Hassam RM, Minson RB, Wing LM, Chalmers JP. Automated non-invasive measurement of cardiac output by the carbon dioxide rebreathing method: comparisons with dye dilution and thermodilution. Heart 1990; 63:195-9. [PMID: 2109625 PMCID: PMC1024406 DOI: 10.1136/hrt.63.3.195] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The accuracy and reproducibility of indirect measurement of cardiac output at rest by the carbon dioxide rebreathing (indirect Fick) method with an automated respiratory analysis system (Gould 9000IV) were compared with simultaneous measurements made in duplicate by dye dilution and thermodilution in 25 patients having cardiac catheterisation studies. Measurements of cardiac output by the carbon dioxide rebreathing method were not significantly different from those obtained with dye dilution (mean difference -0.3 l/min, SD 0.76, 95% confidence interval -0.7 to 0.1). Thermodilution significantly over-estimated cardiac output by a mean of 2.2 l/min or 39% (SD 1.5, 95% confidence interval 1.6 to 2.8) compared with the carbon dioxide rebreathing method and significantly overestimated cardiac output by 1.9 l/min or 31% (SD 1.2, 95% confidence interval 1.2 to 2.5) compared with dye dilution. The reproducibility of measurements of cardiac output in individual patients was satisfactory with the dye dilution method but was poor with carbon dioxide rebreathing and thermodilution. Indirect measurement of resting cardiac output by the Gould 9000IV automated carbon dioxide rebreathing method is more accurate but the variability inherent with this method requires that multiple measurements be taken for each determination. Measurement of cardiac output by the thermodilution method by a commercially available cardiac output computer was not satisfactory because not only was there considerable variability between repeat measurements but the method also consistently overestimated cardiac output compared with the dye dilution method.
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Affiliation(s)
- A E Russell
- Department of Medicine, Flinders Medical Centre, Bedford Park, South Australia
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21
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Aylward PE, Russell AE, Smith SA, Sheppard JM, Stoner JE. The authors reply. Heart 1989; 62:415. [DOI: 10.1136/hrt.62.5.415-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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22
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Russell AE, Wing LM, Smith SA, Aylward PE, McRitchie RJ, Hassam RM, West MJ, Chalmers JP. Optimal size of cuff bladder for indirect measurement of arterial pressure in adults. J Hypertens 1989; 7:607-13. [PMID: 2681407 DOI: 10.1097/00004872-198908000-00002] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
This study tested the hypothesis that a sphygmomanometer cuff bladder long enough to encircle the arm in most adults ('obese cuff') would provide a more accurate and precise estimate of intra-arterial pressure than the usual 'standard' cuff bladder. In 53 patients undergoing diagnostic coronary angiography (35 males, 18 females, aged 36-79 years), indirect blood pressure, measured in the left arm with a random-zero sphygmomanometer, was compared with simultaneously measured femoral intra-arterial pressure. Duplicate indirect measurements were made with each of two cuffs containing bladders measuring 39 x 15 cm ('obese') and 23 x 12 cm ('standard'). The obese cuff bladder encircled 80% or more of the arm circumference in all subjects, whereas the standard cuff bladder met this requirement in only 19% of the subjects. For both systolic and diastolic pressure there was marked interindividual variability in the differences between indirect and direct measurements with both cuffs. With the obese cuff there was no systematic error in the diastolic blood pressure measurement. The standard cuff consistently overestimated diastolic pressure by 7.7 +/- 8.3 mmHg (mean +/- s.d.). For both cuffs, the difference between indirect and direct diastolic pressure increased with arm size (P less than 0.05). Both cuffs underestimated systolic blood pressure, the obese cuff by 15.5 +/- 11.7 mmHg and the standard cuff by 7.6 +/- 12.1 mmHg. These systolic blood pressure underestimates were greater at higher blood pressures (P less than 0.01) and with smaller arms (P less than 0.05). Age was not related to measurement error with either cuff.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- A E Russell
- Department of Medicine, Flinders Medical Centre, Bedford Park, South Australia
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Russell AE, Tonkin AL, Wing LM, Hassam RM, McRitchie RJ, Aylward PE, Minson RB, Bune AJ, West MJ, Chalmers JP. Accuracy of the Takeda TM-2420 ambulatory blood pressure monitor. Clin Exp Pharmacol Physiol 1989; 16:253-6. [PMID: 2743618 DOI: 10.1111/j.1440-1681.1989.tb01553.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
1. The accuracy of blood pressure measurement with the Takeda TM-2420 ambulatory blood pressure monitor and the TM-2020 data recorder have been assessed by comparison with simultaneous measurements taken using auscultation and direct femoral artery measurements. 2. Systolic blood pressure was underestimated by the TM-2420 by a mean of 10 mmHg (s.d. = 6, 95% confidence interval (CI) = -13 to -7) over the range of pressures measured by auscultation. It was underestimated by 23 mmHg (s.d. = 12, 95% CI = -28 to -18) compared with direct femoral artery measurements. 3. Diastolic pressure measurements were similar to those obtained by auscultation. When compared with direct femoral artery recordings, diastolic pressure was overestimated by about 5 mmHg (s.d. = 4, 95% CI = 3.4-6.6), which is consistent with indirect readings, taken with a 'standard' cuff (inflatable bladder 23 cm X 12 cm). 4. The TM-2420/2020 is thus suitable for ambulatory measurements of blood pressure when diastolic pressure is the criterion of interest.
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Affiliation(s)
- A E Russell
- Department of Medicine, Flinders Medical Centre, Bedford Park, South Australia
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Smith SA, Stoner JE, Russell AE, Sheppard JM, Aylward PE. Transmitral velocities measured by pulsed Doppler in healthy volunteers: effects of acute changes in blood pressure and heart rate. Heart 1989; 61:344-7. [PMID: 2653392 PMCID: PMC1216674 DOI: 10.1136/hrt.61.4.344] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The effect of a two minute cold pressor test on transmitral velocities measured by pulsed Doppler was studied in 11 healthy volunteers. Blood pressure increased significantly during cold immersion but peak atrial and peak early diastolic transmitral velocities and their ratio (A:E) were unchanged. There was no correlation between changes in Doppler variables and changes in calculated mean arterial blood pressure during the test. Heart rate changes were variable and not related to changes in blood pressure. In individual people the change in pulse interval during cold immersion was significantly and inversely correlated with the change in the A:E ratio. The large acute increase in arterial pressure seen during the cold pressor test in normal volunteers had no consistent effect on the transmitral velocity profile although small changes in heart rate were associated with large changes in A:E ratio. The effect of small changes in heart rate may be of considerable importance in determining transmitral velocity profiles. Thus in clinical and experimental studies in which the heart rate is not controlled, Doppler data on transmitral flow should be interpreted with caution.
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Affiliation(s)
- S A Smith
- Department of Medicine, Flinders Medical Centre, Bedford Park, South Australia
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Abstract
Previous studies have demonstrated that plasma Neuropeptide Y-like immunoreactivity (NPY-LI) increases after activation of sympathetic nerves. To test the hypothesis that the adrenal medulla may also be a significant source of circulating plasma NPY-LI and to determine if NPY is co-released with adrenal catecholamines, we have measured the peripheral venous concentrations of NPY-LI, adrenaline and noradrenaline in six patients, before and after induction of hypoglycaemia as part of pituitary function tests that also tested gonadotrophin and thyroid stimulating hormone release. The plasma adrenaline concentration was increased approximately 15 times (p less than 0.05) relative to baseline at 30 mins and remained elevated for the 90 minutes of the study. The plasma concentration of both noradrenaline and NPY-LI remained unchanged. These results failed to demonstrate an increase in the amount of NPY-LI released into the plasma during stimulation of the adrenal medulla with hypoglycaemic stress in man. They do not support significant co-release of NPY with adrenaline from the adrenal medulla in man, nor a physiological role for NPY as an adrenal hormone in human subjects in this situation.
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Affiliation(s)
- A E Russell
- Department of Medicine, Flinders Medical Centre, Adelaide, South Australia
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Russell AE, Aylward PE, Smith SA, Cain MD, McRitchie RJ, Chalmers JP. Plasma neuropeptide Y and atrial natriuretic peptide concentrations in man. Clin Exp Pharmacol Physiol 1988; 15:955-8. [PMID: 2977307 DOI: 10.1111/j.1440-1681.1988.tb01041.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
1. In order to examine the concentration of neuropeptide Y-like immunoreactivity (NPY-LI) and atrial natriuretic peptide (ANP) in the circulation in man, blood was sampled from the iliac vein, the inferior vena cava, the superior vena cava, the pulmonary artery and the femoral artery in 13 patients undergoing cardiac catheterization. 2. Plasma NPY-LI levels were similar at all points sampled and no arteriovenous differences were found. Plasma ANP concentration in the pulmonary artery was greater than in peripheral venous blood but there was a strong correlation between the two. 3. The concentration of NPY-LI and ANP in peripheral venous blood reflects central venous and arterial concentrations.
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Affiliation(s)
- A E Russell
- Department of Medicine, Flinders Medical Centre, Adelaide, South Australia
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Smith SA, Russell AE, West MJ, Chalmers J. Automated non-invasive measurement of cardiac output: comparison of electrical bioimpedance and carbon dioxide rebreathing techniques. Heart 1988; 59:292-8. [PMID: 3128316 PMCID: PMC1216462 DOI: 10.1136/hrt.59.3.292] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Two commercial automated, non-invasive systems for estimation of cardiac output were evaluated. Values of cardiac output obtained by electrical bioimpedance cardiography (BoMed NCCOM3 machine) were compared with values derived from an indirect Fick technique that uses carbon dioxide rebreathing (Gould 9000 IV system) during 103 simultaneous measurements made at rest in 19 randomly selected subjects and on exercise in 11 subjects. Cardiac output values obtained with impedance cardiography were significantly correlated with those measured by the indirect Fick method, although there was a wide scatter with over 73% of the readings lying outside the limits defined by the line of identity +/- 20%. This correlation was greatly reduced when stroke volume index was used instead of cardiac output. Indirect Fick results were linearly related to oxygen uptake both at rest and on exercise, while impedance cardiography results did not correlate with oxygen uptake. Impedance cardiography gave consistently lower results for cardiac output than indirect Fick at all levels of exercise. Both machines were easy to use and produced acceptable mean (SE) coefficients of variation (BoMed NCCOM3 7.7 (1.0)%, Gould 9000 IV 10.6 (1.4)%). Further validation is required before either of these machines can be recommended as an alternative to invasive monitoring in clinical practice.
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Affiliation(s)
- S A Smith
- Department of Cardiovascular Medicine, Flinders Medical Centre, Bedford Park, South Australia
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Wing LM, Chalmers JP, West MJ, Russell AE, Morris MJ, Cain MD, Bune AJ, Southgate DO. Enalapril and atenolol in essential hypertension: attenuation of hypotensive effects in combination. Clin Exp Hypertens A 1988; 10:119-33. [PMID: 2832102 DOI: 10.3109/10641968809046803] [Citation(s) in RCA: 17] [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] [Indexed: 01/02/2023]
Abstract
In 16 patients with essential hypertension the effects of enalapril 20 mg once daily were compared with those of atenolol 50 mg once daily, with the two drugs in combination and with placebo using a double-blind cross-over design with allocation of treatment order by randomised Latin squares. For each patient there were four treatment phases, each of four weeks duration, which together comprised a 2 x 2 factorial experiment. All blood pressure parameters were reduced in the three active treatment phases compared to placebo (p less than 0.001). Supine blood pressures (group means) were 171/97 (placebo), 147/85 (enalapril), 154/84 (atenolol) and 144/78 (enalapril plus atenolol) (S.E.M. +/- 2/+/- 1-ANOVA), and standing blood pressures were 170/105 (placebo), 146/92 (enalapril), 154/92 (atenolol) and 147/86 (enalapril plus atenolol) (S.E.M. +/- 3/+/- 1). In the combination phase there was an additional hypotensive response but the potential fully additive effects of the two agents were attenuated by 30-50%. The mechanism of the attenuated hypotensive effect of the combined agents has not been determined. Plasma atrial natriuretic peptide (ANP) concentration was doubled in the presence of atenolol (P less than 0.01) suggesting that ANP may contribute to the hypotensive effect of the beta-blocker.
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Affiliation(s)
- L M Wing
- Flinders Medical Centre, Repatriation General Hospital, Adelaide, South Australia
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Wing LM, Chalmers JP, West MJ, Bune AJ, Russell AE, Elliott JM, Morris MJ. Treatment of hypertension with enalapril and hydrochlorothiazide or enalapril and atenolol: contrasts in hypotensive interactions. J Hypertens Suppl 1987; 5:S603-6. [PMID: 2832575] [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: 01/02/2023]
Abstract
To determine the nature of the resultant effect on blood pressure when angiotensin converting enzyme (ACE) inhibitors are combined with other hypotensive agents in the treatment of uncomplicated essential hypertension, two randomized, double-blind, crossover trials were conducted. In each trial there were four treatment phases, each 4 weeks in duration, comprising a 2 X 2 factorial experiment. Twenty-one patients completed the first study in which the effects of enalapril (10 mg twice daily) were compared with hydrochlorothiazide (25 mg twice daily), with the two drugs in combination and with placebo. All blood pressure parameters were reduced in the three active treatment phases compared with placebo (P less than 0.001). Enalapril and hydrochlorothiazide were equally effective and in combination their hypotensive effects were fully additive. Sixteen patients completed the second study which compared the effects of enalapril (20 mg daily), atenolol (50 mg daily), the two drugs in combination and placebo. All blood pressure parameters were again reduced in all phases compared with placebo (P less than 0.001). Enalapril and atenolol were also equally effective, but in combination their hypotensive effects were less than fully additive, with attenuation of the potential additive response by 30-50%. These results indicate that a diuretic-ACE inhibitor combination can be expected to have a greater hypotensive effect than a beta-blocker-ACE inhibitor combination. Both hydrochlorothiazide and atenolol increased plasma atrial natriuretic peptide (ANP) concentrations (P less than 0.01), suggesting that ANP could contribute to the hypotensive effects of these two drug classes.
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Affiliation(s)
- L M Wing
- Department of Clinical Pharmacology, Flinders Medical Centre, Bedford Park, SA, Australia
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Morris MJ, Russell AE, Kapoor V, Cain MD, Elliott JM, West MJ, Wing LM, Chalmers JP. Increases in plasma neuropeptide Y concentrations during sympathetic activation in man. J Auton Nerv Syst 1986; 17:143-9. [PMID: 3782722 DOI: 10.1016/0165-1838(86)90089-5] [Citation(s) in RCA: 132] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Neuropeptide Y (NPY) coexists with noradrenaline in postganglionic sympathetic neurons. In order to test the hypothesis that NPY may be released along with catecholamines by activation of the sympathoadrenal system we measured plasma NPY-like immunoreactivity (NPY-LI) concentrations during cold pressor test, head up tilt and bicycle exercise in healthy volunteers. All 3 manoeuvres resulted in elevation of blood pressure, heart rate and plasma noradrenaline and adrenaline concentrations. These were accompanied by increases in plasma NPY-LI concentrations on cold pressor test and exercise, but not with head up tilt. The increases in both NPY-LI and catecholamines were greatest with exercise. These findings suggest that NPY is released at the same time as noradrenaline when sympathetic noradrenergic nerves are activated.
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Sparrow NA, Glasser L, Glasser D, Russell AE. Binding isotherms by continuous-flow dynamic dialysis. J Pharm Biomed Anal 1986; 4:461-74. [PMID: 16867582 DOI: 10.1016/0731-7085(86)80067-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/1984] [Revised: 05/16/1985] [Indexed: 11/22/2022]
Abstract
The classical dynamic dialysis technique for the determination of a protein-ligand binding isotherm has been modified by the introduction of a flow cell in which the dialysate on the sink side of the membrane is continuously eluted with a constant flow of eluting buffer and its ligand concentration measured. This new experimental method is termed continuous-flow dynamic dialysis (CFDD). A transfer function procedure for extracting the binding isotherm from the dialysis data is described. This is a more general technique (requiring only a verifiable assumption of linearity) than that previously used, in which the system was modelled using Fick's first law and which relied on the establishment of quasi-steady state conditions across the membrane. The present analysis uses the Laplace transform to effect deconvolution of the impulse response function of the cell from the dialysis data and, using a Fourier series approach, directly yields numerical data representing the free ligand concentration in equilibrium with the protein-ligand complex. The protein-ligand binding isotherm is obtained in parametric form, with time as the parameter.
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Affiliation(s)
- N A Sparrow
- Leather Industries Research Institute, Rhodes University, P.O. Box 185, Grahamstown 6140, South Africa
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Abstract
Thermal stabilities of mature insoluble collagen, salt-precipitated fibrils of acid-soluble collagen and acid-soluble collagen in solution were compared as a function of acid pH. Both insoluble and precipitated collagens showed large parallel destabilization with decrease in pH, whereas the intrinsic stability of individual collagen molecules in dilute solution was comparatively unaffected.
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Abstract
The effects of KCNS and KI on thermal transition temperatures of calf skin collagen molecules in dilute acid solution and precipitated collagen fibrils from the same source were compared as a function of salt concentration and pH. The two salts produced qualitatively similar effects on each collagen form, but the response shown by single collagen molecules in dilute solution differed from that observed for molecular aggregates present in native-type fibrils.
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Abstract
The effects of mono- and poly-hydric alcohols in the presence of KCl on the intrinsic stability of collagen molecules in dilute acid solution were compared with corresponding solvent and salt effects on the increased stability of the aggregated molecules in salt-precipitated fibrils. Salt addition decreased solubility and increased the thermal stability of fibrils, but progressively decreased the stability of collagen molecules in solution. In contrast, the alcohols enhanced solubility and decreased fibril stability, the effects increasing with solvent hydrocarbon chain length and with decreasing hydroxyl/methylene-group ratio. Molar destabilization of dissolved collagen by alcohols was lower than for fibrils, and at low salt concentration, both ethylene glycol and glycerol were structural stabilizers. Electron-micrograph studies indicated that salt-precipitated fibrils tended to adopt the native aggregation mode, and qualitatively similar solvent effects were observed in insoluble collagens. Implications of the experimental findings are discussed in terms of a model in which electrostatic and apolar interactions mainly govern the excess of stability in collagen fibrils whereas intrinsic stability of single molecules is a function of polar interactions and polypeptide-chain rigidity.
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Russell AE, Cooper DR. Effect of compounds of the urea-guanidinium class on renaturation and thermal stability of acid-soluble collagen. Biochem J 1972; 127:855-63. [PMID: 4672803 PMCID: PMC1178795 DOI: 10.1042/bj1270855] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The effects of guanidinium salts in decreasing the renaturation rate and lowering the thermal stability of acid-soluble calf-skin collagen have been compared with those of formamide and urea. With the exception of guanidinium sulphate at higher concentrations, no qualitative differences were apparent in the effects of these perturbants, which thus differed only in molar activity. Activity variation in the guanidinium salts reflected a net effect resulting from additivity of cation and anion contributions. As observed in other protein systems, lyotropic activity increased in the series formamide<urea<guanidinium ion, and in the guanidinium salts in the anion order fluoride<sulphate<chloride<bromide<nitrate<iodide. Low activities of guanidinium fluoride and sulphate were attributable to counter-effects of the anions, which acted as structural stabilizers. Changes in renaturation kinetics induced by either temperature or added perturbants appeared to conform with the Flory-Weaver model for the collagen transition. Additivity and non-specificity of the observed effects are discussed with particular reference to a common mechanism involving weak, non-saturated binding of perturbants at protein peptide groups.
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Abstract
The effects of a number of related glycols and substituted glycols on the renaturation kinetics of acid-soluble calf-skin collagen have been investigated. Optical rotation recovery was monitored at a fixed temperature in the presence of perturbants and the initial rates of reaction were determined. The effects of perturbants on stability of the native protein are compared with their action in the renaturing systems. The relationship between initial recovery rates and fixed-time [alpha]-values is shown to be dependent upon the renaturation temperature. The influence of perturbant concentration on recovery rates is discussed in terms of present theories of the mechanism of collagen renaturation.
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Hart GJ, Russell AE, Cooper DR. The effects of certain glycols, substituted glycols and related organic solvents on the thermal stability of soluble collagen. Biochem J 1971; 125:599-604. [PMID: 5169191 PMCID: PMC1178097 DOI: 10.1042/bj1250599] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The effects of a number of related diols, substituted diols and glycerol on the thermal stability of acid-soluble calf skin collagen were investigated. Thermal transition temperatures were determined by optical rotation measurement. Short-chain diols with terminal hydroxyl groups, i.e. ethylene glycol and propane-1,3-diol, stabilized the protein at all accessible concentrations. Stabilization was also observed with glycerol and diethylene glycol. Higher homologues in the diol series produced various effects, as did hydroxyl-group positional isomerism. Monoalkyl substitution of diols progressively lowered the denaturation temperature of collagen. Results are discussed in relation to possible mechanisms of perturbant action.
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Russell AE, Cooper DR. Comparison of lyotropic and chromatographic effects of polar organic solvents on collagen and cellulose. Biochemistry 1971; 10:3890-6. [PMID: 5160416 DOI: 10.1021/bi00797a015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Russell AE, Cooper DR. Structural and functional factors in the lyotropic activity of amides and alkyl-substituted amides on acid-soluble collagen. Biochemistry 1970; 9:2802-6. [PMID: 5459533 DOI: 10.1021/bi00816a008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Cooper DR, Russell AE. Intra- and intermolecular crosslinks in collagen in tendon, cartilage and bone. Clin Orthop Relat Res 1969; 67:188-209. [PMID: 4903341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Russell AE, Cooper DR. Structural and functional factors in the hydrogen bonding of polar organic solvents to acid-soluble collagen. Effect on renaturation kinetics and thermal stability. Biochemistry 1969; 8:3980-90. [PMID: 5346381 DOI: 10.1021/bi00838a014] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Abstract
1. The effect of gamma-irradiation in the range 1 krad-10 Mrads on freeze-dried acid-soluble collagen was studied. 2. The specific-rotation and reduced-viscosity recoveries after heating and cooling of the irradiated collagen in solution showed a high degree of dependence on irradiation dose, with reduced viscosity showing significantly less recovery than specific rotation on increasing the irradiation dose. 3. The dependence of reduced viscosity on concentration was greatly decreased with increased doses of gamma-irradiation. 4. The melting temperature measured by optical rotation also decreased as the irradiation dose was increased, and at low doses was distinctly biphasic. 5. Physical properties showed that the action of gamma-irradiation up to 10 Mrads occurred in two distinct phases, with the early changes being extremely sensitive to irradiation dose. 6. The action of the gamma-irradiation is discussed in terms of the structure of tropocollagen.
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Russell AE, Zuckerman S. A "Sexual Skin" in a Marmoset. J Anat 1935; 69:356-362.1. [PMID: 17104541 PMCID: PMC1249084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023] Open
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Harris HA, Russell AE. The Atypical Growth in Cartilage as the Fundamental Factor in Dwarfism and Achondroplasia. Proc R Soc Med 1933; 26:779-787. [PMID: 19989278 PMCID: PMC2204493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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Russell AE. Cyclic or Recurrent Vomiting associated with Hypertrophic Stenosis of the Pylorus. Proc R Soc Med 1910; 3:78-88. [PMID: 19974791 PMCID: PMC1961291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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Russell AE, Sargent P. Apoplectiform Cerebral Hæmorrhage. Operation. Evacuation of Blood. Slow Improvement. Proc R Soc Med 1909; 2:44-51. [PMID: 20898192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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Russell AE, Sargent P. Apoplectiform Cerebral Hæmorrhage. Operation. Evacuation of Blood. Slow Improvement. Proc R Soc Med 1909; 2:44-51. [PMID: 19973795 PMCID: PMC2046562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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