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Gabb VG, Blackman J, Morrison HD, Biswas B, Li H, Turner N, Russell GM, Greenwood R, Jolly A, Trender W, Hampshire A, Whone A, Coulthard E. Remote Evaluation of Sleep and Circadian Rhythms in Older Adults With Mild Cognitive Impairment and Dementia: Protocol for a Feasibility and Acceptability Mixed Methods Study. JMIR Res Protoc 2024; 13:e52652. [PMID: 38517469 PMCID: PMC10998181 DOI: 10.2196/52652] [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: 09/19/2023] [Revised: 02/12/2024] [Accepted: 02/13/2024] [Indexed: 03/23/2024] Open
Abstract
BACKGROUND Sleep disturbances are a potentially modifiable risk factor for neurodegenerative dementia secondary to Alzheimer disease (AD) and Lewy body disease (LBD). Therefore, we need to identify the best methods to study sleep in this population. OBJECTIVE This study will assess the feasibility and acceptability of various wearable devices, smart devices, and remote study tasks in sleep and cognition research for people with AD and LBD. METHODS We will deliver a feasibility and acceptability study alongside a prospective observational cohort study assessing sleep and cognition longitudinally in the home environment. Adults aged older than 50 years who were diagnosed with mild to moderate dementia or mild cognitive impairment (MCI) due to probable AD or LBD and age-matched controls will be eligible. Exclusion criteria include lack of capacity to consent to research, other causes of MCI or dementia, and clinically significant sleep disorders. Participants will complete a cognitive assessment and questionnaires with a researcher and receive training and instructions for at-home study tasks across 8 weeks. At-home study tasks include remote sleep assessments using wearable devices (electroencephalography headband and actigraphy watch), app-based sleep diaries, online cognitive assessments, and saliva samples for melatonin- and cortisol-derived circadian markers. Feasibility outcomes will be assessed relating to recruitment and retention, data completeness, data quality, and support required. Feedback on acceptability and usability will be collected throughout the study period and end-of-study interviews will be analyzed using thematic analysis. RESULTS Recruitment started in February 2022. Data collection is ongoing, with final data expected in February 2024 and data analysis and publication of findings scheduled for the summer of 2024. CONCLUSIONS This study will allow us to assess if remote testing using smart devices and wearable technology is a viable alternative to traditional sleep measurements, such as polysomnography and questionnaires, in older adults with and without MCI or dementia due to AD or LBD. Understanding participant experience and the barriers and facilitators to technology use for research purposes and remote research in this population will assist with the development of, recruitment to, and retention within future research projects studying sleep and cognition outside of the clinic or laboratory. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID) DERR1-10.2196/52652.
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Affiliation(s)
- Victoria Grace Gabb
- Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Neurology Department, Bristol Brain Centre, North Bristol NHS Trust, Bristol, United Kingdom
| | - Jonathan Blackman
- Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Neurology Department, Bristol Brain Centre, North Bristol NHS Trust, Bristol, United Kingdom
| | - Hamish Duncan Morrison
- Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Neurology Department, Bristol Brain Centre, North Bristol NHS Trust, Bristol, United Kingdom
| | - Bijetri Biswas
- Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Haoxuan Li
- Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Neurology Department, Bristol Brain Centre, North Bristol NHS Trust, Bristol, United Kingdom
- King's College Hospital, King's College Hospital NHS Foundation Trust, London, United Kingdom
- Bristol Royal Infirmary, University Hospitals Bristol and Weston NHS Foundation Trust, Bristol, United Kingdom
| | - Nicholas Turner
- Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | | | - Rosemary Greenwood
- Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Research & Innovation, University Hospitals Bristol and Weston NHS Foundation Trust, Bristol, United Kingdom
| | - Amy Jolly
- Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
- UCL Queen Square Institute of Neurology, Faculty of Brain Sciences, University College London, London, United Kingdom
| | - William Trender
- Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Adam Hampshire
- Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Alan Whone
- Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Neurology Department, Bristol Brain Centre, North Bristol NHS Trust, Bristol, United Kingdom
| | - Elizabeth Coulthard
- Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Neurology Department, Bristol Brain Centre, North Bristol NHS Trust, Bristol, United Kingdom
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Habets PC, Kalafatakis K, Dzyubachyk O, van der Werff SJ, Keo A, Thakrar J, Mahfouz A, Pereira AM, Russell GM, Lightman SL, Meijer OC. Transcriptional and cell type profiles of cortical brain regions showing ultradian cortisol rhythm dependent responses to emotional face stimulation. Neurobiol Stress 2023; 22:100514. [PMID: 36660181 PMCID: PMC9842700 DOI: 10.1016/j.ynstr.2023.100514] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 01/02/2023] [Accepted: 01/02/2023] [Indexed: 01/05/2023] Open
Abstract
The characteristic endogenous circadian rhythm of plasma glucocorticoid concentrations is made up from an underlying ultradian pulsatile secretory pattern. Recent evidence has indicated that this ultradian cortisol pulsatility is crucial for normal emotional response in man. In this study, we investigate the anatomical transcriptional and cell type signature of brain regions sensitive to a loss of ultradian rhythmicity in the context of emotional processing. We combine human cell type and transcriptomic atlas data of high spatial resolution with functional magnetic resonance imaging (fMRI) data. We show that the loss of cortisol ultradian rhythm alters emotional processing response in cortical brain areas that are characterized by transcriptional and cellular profiles of GABAergic function. We find that two previously identified key components of rapid non-genomic GC signaling - the ANXA1 gene and retrograde endocannabinoid signaling - show most significant differential expression (q = 3.99e-10) and enrichment (fold enrichment = 5.56, q = 9.09e-4). Our results further indicate that specific cell types, including a specific NPY-expressing GABAergic neuronal cell type, and specific G protein signaling cascades underly the cerebral effects of a loss of ultradian cortisol rhythm. Our results provide a biological mechanistic underpinning of our fMRI findings, indicating specific cell types and cascades as a target for manipulation in future experimental studies.
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Affiliation(s)
- Philippe C. Habets
- Leiden University Medical Center, Department of Medicine, Division of Endocrinology, 2300 RC Leiden, the Netherlands,Amsterdam University Medical Centre, Department of Psychiatry, Department of Anatomy and Neurosciences, 1081 HZ, Amsterdam, the Netherlands,Corresponding author. Leiden University Medical Center, Department of Medicine, Division of Endocrinology, 2300 RC Leiden, the Netherlands.
| | - Konstantinos Kalafatakis
- Henry Wellcome Laboratories of Integrative Neuroscience and Endocrinology, Bristol Medical School, University of Bristol, BS1 3NY, Bristol, United Kingdom,Institute of Health Science Education, Barts and the London School of Medicine & Dentistry, Queen Mary University of London Malta Campus, VCT 2520, Victoria Gozo, Malta
| | - Oleh Dzyubachyk
- Department of Radiology, Division of Medical Image Processing, Leiden University Medical Center, 2333 ZA, Leiden, the Netherlands,Leiden University Medical Center, Department of Cell and Chemical Biology, Section Electron Microscopy, 2300 RC, Leiden, the Netherlands
| | - Steven J.A. van der Werff
- Department of Psychiatry, Leiden University Medical Center LUMC, Leiden, the Netherlands,Leiden Institute for Brain and Cognition, Leiden, the Netherlands
| | - Arlin Keo
- Leiden Computational Biology Center, Leiden University Medical Center, Leiden, the Netherlands,Delft Bioinformatics Lab, Delft University of Technology, Delft, the Netherlands
| | - Jamini Thakrar
- Henry Wellcome Laboratories of Integrative Neuroscience and Endocrinology, Bristol Medical School, University of Bristol, BS1 3NY, Bristol, United Kingdom
| | - Ahmed Mahfouz
- Leiden Computational Biology Center, Leiden University Medical Center, Leiden, the Netherlands,Delft Bioinformatics Lab, Delft University of Technology, Delft, the Netherlands,Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
| | - Alberto M. Pereira
- Leiden University Medical Center, Department of Medicine, Division of Endocrinology, 2300 RC Leiden, the Netherlands,Department of Endocrinology & Metabolism, Amsterdam University Medical Center, Amsterdam, the Netherlands
| | - Georgina M. Russell
- Henry Wellcome Laboratories of Integrative Neuroscience and Endocrinology, Bristol Medical School, University of Bristol, BS1 3NY, Bristol, United Kingdom
| | - Stafford L. Lightman
- Henry Wellcome Laboratories of Integrative Neuroscience and Endocrinology, Bristol Medical School, University of Bristol, BS1 3NY, Bristol, United Kingdom
| | - Onno C. Meijer
- Leiden University Medical Center, Department of Medicine, Division of Endocrinology, 2300 RC Leiden, the Netherlands,Leiden Institute for Brain and Cognition, Leiden, the Netherlands
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Violaris IG, Kalafatakis K, Zavala E, Tsoulos IG, Lampros T, Lightman SL, Tsipouras MG, Giannakeas N, Tzallas A, Russell GM. Modelling Hydrocortisone Pharmacokinetics on a Subcutaneous Pulsatile Infusion Replacement Strategy in Patients with Adrenocortical Insufficiency. Pharmaceutics 2021; 13:pharmaceutics13060769. [PMID: 34064165 PMCID: PMC8224376 DOI: 10.3390/pharmaceutics13060769] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/17/2021] [Accepted: 05/18/2021] [Indexed: 11/16/2022] Open
Abstract
In the context of glucocorticoid (GC) therapeutics, recent studies have utilised a subcutaneous hydrocortisone (HC) infusion pump programmed to deliver multiple HC pulses throughout the day, with the purpose of restoring normal circadian and ultradian GC rhythmicity. A key challenge for the advancement of novel HC replacement therapies is the calibration of infusion pumps against cortisol levels measured in blood. However, repeated blood sampling sessions are enormously labour-intensive for both examiners and examinees. These sessions also have a cost, are time consuming and are occasionally unfeasible. To address this, we developed a pharmacokinetic model approximating the values of plasma cortisol levels at any point of the day from a limited number of plasma cortisol measurements. The model was validated using the plasma cortisol profiles of 9 subjects with disrupted endogenous GC synthetic capacity. The model accurately predicted plasma cortisol levels (mean absolute percentage error of 14%) when only four plasma cortisol measurements were provided. Although our model did not predict GC dynamics when HC was administered in a way other than subcutaneously or in individuals whose endogenous capacity to produce GCs is intact, it was found to successfully be used to support clinical trials (or practice) involving subcutaneous HC delivery in patients with reduced endogenous capacity to synthesize GCs.
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Affiliation(s)
- Ioannis G. Violaris
- Department of Electrical and Computer Engineering, University of Western Macedonia, 50131 Kozani, Greece; (I.G.V.); (M.G.T.)
| | - Konstantinos Kalafatakis
- Laboratories of Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, Bristol BS1 3NY, UK; (S.L.L.); (G.M.R.)
- Department of Informatics & Telecommunications, School of Informatics & Telecommunications, University of Ioannina, 47100 Arta, Greece; (I.G.T.); (T.L.); (N.G.); (A.T.)
- Correspondence: or ; Tel.: +30-2107288264
| | - Eder Zavala
- Centre for Systems Modelling and Quantitative Biomedicine, Institute of Metabolism and Systems Research, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK;
| | - Ioannis G. Tsoulos
- Department of Informatics & Telecommunications, School of Informatics & Telecommunications, University of Ioannina, 47100 Arta, Greece; (I.G.T.); (T.L.); (N.G.); (A.T.)
| | - Theodoros Lampros
- Department of Informatics & Telecommunications, School of Informatics & Telecommunications, University of Ioannina, 47100 Arta, Greece; (I.G.T.); (T.L.); (N.G.); (A.T.)
| | - Stafford L. Lightman
- Laboratories of Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, Bristol BS1 3NY, UK; (S.L.L.); (G.M.R.)
| | - Markos G. Tsipouras
- Department of Electrical and Computer Engineering, University of Western Macedonia, 50131 Kozani, Greece; (I.G.V.); (M.G.T.)
| | - Nikolaos Giannakeas
- Department of Informatics & Telecommunications, School of Informatics & Telecommunications, University of Ioannina, 47100 Arta, Greece; (I.G.T.); (T.L.); (N.G.); (A.T.)
| | - Alexandros Tzallas
- Department of Informatics & Telecommunications, School of Informatics & Telecommunications, University of Ioannina, 47100 Arta, Greece; (I.G.T.); (T.L.); (N.G.); (A.T.)
| | - Georgina M. Russell
- Laboratories of Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, Bristol BS1 3NY, UK; (S.L.L.); (G.M.R.)
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Kalafatakis K, Russell GM, Ferguson SG, Grabski M, Harmer CJ, Munafò MR, Marchant N, Wilson A, Brooks JC, Thakrar J, Murphy P, Thai NJ, Lightman SL. Glucocorticoid ultradian rhythmicity differentially regulates mood and resting state networks in the human brain: A randomised controlled clinical trial. Psychoneuroendocrinology 2021; 124:105096. [PMID: 33296841 PMCID: PMC7895801 DOI: 10.1016/j.psyneuen.2020.105096] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 10/23/2020] [Accepted: 11/26/2020] [Indexed: 12/17/2022]
Abstract
Adrenal glucocorticoid secretion into the systematic circulation is characterised by a complex rhythm, composed of the diurnal variation, formed by changes in pulse amplitude of an underlying ultradian rhythm of short duration hormonal pulses. To elucidate the potential neurobiological significance of glucocorticoid pulsatility in man, we have conducted a randomised, double-blind, placebo-controlled, three-way crossover clinical trial on 15 healthy volunteers, investigating the impact of different glucocorticoid rhythms on measures of mood and neural activity under resting conditions by recruiting functional neuroimaging, computerised behavioural tests and ecological momentary assessments. Endogenous glucocorticoid biosynthesis was pharmacologically suppressed, and plasma levels of corticosteroid restored by hydrocortisone replacement in three different regimes, either mimicking the normal ultradian and circadian profile of the hormone, or retaining the normal circadian but abolishing the ultradian rhythm of the hormone, or by our current best oral replacement regime which results in a suboptimal circadian and ultradian rhythm. Our results indicate that changes in the temporal mode of glucocorticoid replacement impact (i) the morning levels of self-perceived vigour, fatigue and concentration, (ii) the diurnal pattern of mood variation, (iii) the within-network functional connectivity of various large-scale resting state networks of the human brain, (iv) the functional connectivity of the default-mode, salience and executive control networks with glucocorticoid-sensitive nodes of the corticolimbic system, and (v) the functional relationship between mood variation and underlying neural networks. The findings indicate that the pattern of the ultradian glucocorticoid rhythm could affect cognitive psychophysiology under non-stressful conditions and opens new pathways for our understanding on the neuropsychological effects of cortisol pulsatility with relevance to the goal of optimising glucocorticoid replacement strategies.
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Affiliation(s)
- Konstantinos Kalafatakis
- Laboratories of Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, BS1 3NY Bristol, United Kingdom; Clinical Research and Imaging Centre, University of Bristol and University Hospitals Bristol NHS Foundation Trust, BS2 8DX Bristol, United Kingdom; Royal Bristol Infirmary, University Hospitals Bristol NHS Foundation Trust, BS2 8HW Bristol, United Kingdom.
| | - Georgina M Russell
- Laboratories of Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, BS1 3NY Bristol, United Kingdom; Royal Bristol Infirmary, University Hospitals Bristol NHS Foundation Trust, BS2 8HW Bristol, United Kingdom
| | - Stuart G Ferguson
- School of Medicine, University of Tasmania, Hobart, TAS 7000, Australia
| | - Meryem Grabski
- Clinical Psychopharmacology Unit, Division of Psychology and Language Sciences, University College London, WC1E 6BT London, United Kingdom; MRC Integrative Epidemiology Unit, School of Psychological Science, University of Bristol, BS8 1TU Bristol, United Kingdom
| | - Catherine J Harmer
- Department of Psychiatry, Oxford University and Oxford Health NHS Foundation Trust, OX3 7JX Oxford, United Kingdom
| | - Marcus R Munafò
- MRC Integrative Epidemiology Unit, School of Psychological Science, University of Bristol, BS8 1TU Bristol, United Kingdom
| | - Nicola Marchant
- Laboratories of Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, BS1 3NY Bristol, United Kingdom; Royal Bristol Infirmary, University Hospitals Bristol NHS Foundation Trust, BS2 8HW Bristol, United Kingdom
| | - Aileen Wilson
- Clinical Research and Imaging Centre, University of Bristol and University Hospitals Bristol NHS Foundation Trust, BS2 8DX Bristol, United Kingdom
| | - Jonathan C Brooks
- Clinical Research and Imaging Centre, University of Bristol and University Hospitals Bristol NHS Foundation Trust, BS2 8DX Bristol, United Kingdom
| | - Jamini Thakrar
- Laboratories of Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, BS1 3NY Bristol, United Kingdom; Clinical Research and Imaging Centre, University of Bristol and University Hospitals Bristol NHS Foundation Trust, BS2 8DX Bristol, United Kingdom; Royal Bristol Infirmary, University Hospitals Bristol NHS Foundation Trust, BS2 8HW Bristol, United Kingdom
| | - Patrick Murphy
- Laboratories of Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, BS1 3NY Bristol, United Kingdom; Royal Bristol Infirmary, University Hospitals Bristol NHS Foundation Trust, BS2 8HW Bristol, United Kingdom
| | - Ngoc J Thai
- Clinical Research and Imaging Centre, University of Bristol and University Hospitals Bristol NHS Foundation Trust, BS2 8DX Bristol, United Kingdom
| | - Stafford L Lightman
- Laboratories of Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, BS1 3NY Bristol, United Kingdom; Royal Bristol Infirmary, University Hospitals Bristol NHS Foundation Trust, BS2 8HW Bristol, United Kingdom
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Bhake R, Russell GM, Kershaw Y, Stevens K, Zaccardi F, Warburton VEC, Linthorst ACE, Lightman SL. Continuous Free Cortisol Profiles in Healthy Men. J Clin Endocrinol Metab 2020; 105:5570194. [PMID: 31529059 DOI: 10.1210/clinem/dgz002] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Accepted: 09/08/2019] [Indexed: 12/26/2022]
Abstract
CONTEXT In humans, approximately 95% of circulating cortisol is bound to corticosteroid-binding globulin and albumin. It is only the free fraction that is biologically active and can activate signaling pathways via glucocorticoid hormone receptors in cells. Microdialysis is a well-established technique that enables the sampling of molecules in different compartments of the body, including extracellular fluid. This is the first study validating a rapid sampling microdialysis method measuring free cortisol in the subcutaneous and blood compartments of healthy volunteers. METHODS Healthy nonsmoking volunteers (42 men, aged 18-24 years; body mass index 18-25 kg/m2) received placebo (saline), 250 μg Synacthen, or 1 mg dexamethasone with 10-minute sampling to measure total and free cortisol (subcutaneous, intravenous, and saliva) for an hour before and 4 hours after administration. RESULTS Following stimulation by Synacthen, total serum cortisol and free cortisol in both compartments rose significantly, achieving and maintaining maximum levels between 2 and 3 hours following the stimulus. A decline in cortisol levels was evident after the administration of dexamethasone or placebo, but there was a clear pulsatile activity around lunchtime in the latter group, which was prominent in the blood compartment (total and free cortisol). There was good correlation between serum total and free cortisol (subcutaneous and intravenous) in the Synacthen and dexamethasone groups with no significant delay (less than 5 minutes) between total and free cortisol. CONCLUSIONS This seminal study demonstrated the dynamic responses of total blood cortisol and microdialysis derived free cortisol in blood, subcutaneous tissue, and saliva in men.
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Affiliation(s)
- Ragini Bhake
- University Hospitals Leicester NHS Trust, Leicester, UK
| | - Georgina M Russell
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, Bristol Medical School, University of Bristol, Bristol, UK
| | - Yvonne Kershaw
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, Bristol Medical School, University of Bristol, Bristol, UK
| | - Kara Stevens
- Medical Statistics, Faculty of Health: Medicine, Dentistry and Human Sciences, University of Plymouth, Plymouth, UK
| | - Francesco Zaccardi
- Leicester Real World Evidence Unit, Leicester Diabetes Centre, University of Leicester, Leicester, UK
| | | | - Astrid C E Linthorst
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, Bristol Medical School, University of Bristol, Bristol, UK
| | - Stafford L Lightman
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, Bristol Medical School, University of Bristol, Bristol, UK
- University Hospitals Bristol NHS Foundation Trust, Bristol, UK
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Bhake RC, Kluckner V, Stassen H, Russell GM, Leendertz J, Stevens K, Linthorst ACE, Lightman SL. Continuous Free Cortisol Profiles-Circadian Rhythms in Healthy Men. J Clin Endocrinol Metab 2019; 104:5935-5947. [PMID: 31355884 DOI: 10.1210/jc.2019-00449] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 07/23/2019] [Indexed: 12/26/2022]
Abstract
CONTEXT The pituitary-adrenal axis had historically been considered a representative model for circadian rhythms. A recently developed portable collection device has provided the opportunity to evaluate free cortisol profiles using the microdialysis approach in individuals free to conduct their day-to-day activities in their own surroundings. METHODS Two separate experiments were conducted in healthy male volunteers. The total and subcutaneous (SC) free cortisol levels were measured at 10-minute intervals for a 24-hour period in one experiment, and the SC free cortisol levels were measured at 20-minute interval for 72 consecutive hours in free-living individuals in the second experiment. RESULTS The characteristic circadian rhythm was evident in both serum total and SC free cortisol, with the lowest levels achieved and maintained in the hours surrounding sleep onset and the peak levels occurring in every individual around waking. In all free-living individuals, the circadian rhythm was consistent across the 72-hour period, despite a wide range of activities. All the participants also showed increased cortisol after the consumption of lunch. The lowest levels during all 24-hour periods were observed during the hours after lights off, at the onset of sleep. CONCLUSIONS To the best of our knowledge, the present study is the first to report up to three consecutive 24-hour measurements of SC free cortisol in healthy individuals. We believe our study is a landmark study that paves the way for ambulatory monitoring of free cortisol profiles continuously for a period of 72 hours in free-living individuals performing their day-to-day activities whether healthy or with diseases involving the hypothalamic-pituitary-adrenal axis.
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Affiliation(s)
- R C Bhake
- University Hospitals Leicester National Health Service Trust, Leicester, United Kingdom
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, United Kingdom
| | - V Kluckner
- Department of Psychiatry, Psychotherapy, and Psychosomatics, University of Zurich, Zurich, Switzerland
| | - H Stassen
- Department of Psychiatry, Psychotherapy, and Psychosomatics, University of Zurich, Zurich, Switzerland
| | - G M Russell
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, United Kingdom
| | - J Leendertz
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, United Kingdom
| | - K Stevens
- Department of Medical Statistics, Faculty of Health: Medicine, Dentistry, and Human Sciences, University of Plymouth, Plymouth, United Kingdom
| | - A C E Linthorst
- Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - S L Lightman
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, United Kingdom
- University Hospitals Bristol National Health Service Foundation Trust, Bristol, United Kingdom
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Kalafatakis K, Giannakeas N, Lightman SL, Charalampopoulos I, Russell GM, Tsipouras M, Tzallas A. Utilization of the allen gene expression atlas to gain further insight into glucocorticoid physiology in the adult mouse brain. Neurosci Lett 2019; 706:194-200. [PMID: 31100428 DOI: 10.1016/j.neulet.2019.05.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [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: 01/11/2019] [Revised: 05/05/2019] [Accepted: 05/13/2019] [Indexed: 11/15/2022]
Abstract
Glucocorticoid neurodynamics are the most crucial determinant of the hormonal effects in the mammalian brain, and depend on multiple parallel receptor and enzymatic systems, responsible for effectively binding with the hormone (and mediating its downstream molecular effects) and altering the local glucocorticoid content (by adding, removing or degrading glucocorticoids), respectively. In this study, we combined different computational tools to extract, process and visualize the gene expression data of 25 genes across 96 regions of the adult C57Bl/6J mouse brain, implicated in glucocorticoid neurodynamics. These data derive from the anatomic gene expression atlas of the adult mouse brain of the Allen Institute for Brain Science, captured via the in situ hybridization technique. A careful interrogation of the datasets referring to these 25 genes of interest, based on a targeted, prior knowledge-driven approach, revealed useful pieces of information on spatial differences in the glucocorticoid-sensitive receptors, in the regional capacity for local glucocorticoid biosynthesis, excretion, conversion to other biologically active forms and degradation. These data support the importance of the corticolimbic system of the mammalian brain in mediating glucocorticoid effects, and particularly hippocampus, as well as the need for intensifying the research efforts on the hormonal role in sensory processing, executive control function, its interplay with brain-derived neurotrophic factor and the molecular basis for the regional susceptibility of the brain to states of prolonged high hormonal levels. Future work could expand this methodology by exploiting Allen Institute's databases from other species, introducing complex tools of data analysis and combined analysis of different sources of biological datasets.
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Affiliation(s)
- Konstantinos Kalafatakis
- Department of Informatics & Telecommunications, School of Informatics & Telecommunications, University of Ioannina, Arta, Greece; Laboratories for Integrative Neuroscience and Endocrinology, Bristol Medical School, University of Bristol, Bristol, United Kingdom.
| | - Nikolaos Giannakeas
- Department of Informatics & Telecommunications, School of Informatics & Telecommunications, University of Ioannina, Arta, Greece
| | - Stafford L Lightman
- Laboratories for Integrative Neuroscience and Endocrinology, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Ioannis Charalampopoulos
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, Crete, Greece; Institute of Molecular Biology and Biotechnology, Foundation of Research and Technology Hellas, Heraklion, Crete, Greece
| | - Georgina M Russell
- Laboratories for Integrative Neuroscience and Endocrinology, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Markos Tsipouras
- Department of Informatics & Telecommunications, School of Informatics & Telecommunications, University of Ioannina, Arta, Greece
| | - Alexandros Tzallas
- Department of Informatics & Telecommunications, School of Informatics & Telecommunications, University of Ioannina, Arta, Greece
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Kalafatakis K, Russell GM, Lightman SL. MECHANISMS IN ENDOCRINOLOGY: Does circadian and ultradian glucocorticoid exposure affect the brain? Eur J Endocrinol 2019; 180:R73-R89. [PMID: 30481157 DOI: 10.1530/eje-18-0853] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 11/23/2018] [Indexed: 11/08/2022]
Abstract
Glucocorticoids are a class of systematically secreted hormones, vital for mammalian life, which are intensively investigated for more than 80 years. They regulate multiple body processes like metabolism, fluid homeostasis, immune and stress system responsivity, as well as brain function. Glucocorticoids have a complex rhythm by which they are released to circulation from the adrenal cortex. The hormone exhibits a circadian variation, with high hormonal levels being secreted just prior and during the active part of the day, and progressively lower and lower amounts being released during the inactive part of it. Underlying this diurnal variation there is a more dynamic, ultradian rhythm composed of frequent episodes of glucocorticoid secretion (hormonal pulses). Accumulating evidence from observational, in silico, in vitro and in vivo, preclinical and clinical studies suggest that both aspects of glucocorticoid rhythmicity are preserved among mammalian species and are important for brain function. The central nervous system is exposed to both aspects of the hormonal rhythm and has developed mechanisms able to perceive them and translate them to differential cellular events, genomic and non-genomic. Thus, glucocorticoid rhythmicity regulates various physiological neural and glial processes, under baseline and stressful conditions, and hormonal dysrhythmicity has been associated with cognitive and behavioural defects. This raises a number of clinical implications concerning (i) glucocorticoid involvement in neuropsychiatric disease and (ii) improving the therapeutic efficacy or expanding the role of glucocorticoid-based treatments in such conditions.
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Kalafatakis K, Russell GM, Harmer CJ, Munafo MR, Marchant N, Wilson A, Brooks JCW, Thai NJ, Ferguson SG, Stevenson K, Durant C, Schmidt K, Lightman SL. Effects of the pattern of glucocorticoid replacement on neural processing, emotional reactivity and well-being in healthy male individuals: study protocol for a randomised controlled trial. Trials 2016; 17:44. [PMID: 26801980 PMCID: PMC4724084 DOI: 10.1186/s13063-016-1159-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 01/06/2016] [Indexed: 01/31/2023] Open
Abstract
Background Deviation from the physiological glucocorticoid dynamics (circadian and underlying ultradian rhythmicity) is a common characteristic of various neuropsychiatric and endocrine disorders as well as glucocorticoid-based therapeutics. These states may be accompanied by neuropsychiatric symptomatology, suggesting continuous dynamic glucocorticoid equilibrium is essential for brain homeostasis. Methods/design The study consists of two parts. The preliminary stage of the study aims to validate (technically and pharmacologically) and optimise three different patterns of systemic cortisol administration in man. These patterns are based on the combinatory administration of metyrapone, to suppress endogenous cortisol production, and concurrent hydrocortisone replacement. The second, subsequent, core part of the study is a randomised, double-blinded, placebo-controlled, crossover study, where participants (healthy male individuals aged 18–60 years) will undergo all three hydrocortisone replacement schemes. During these infusion regimes, we plan a number of neurobehavioural tests and imaging of the brain to assess neural processing, emotional reactivity and perception, mood and self-perceived well-being. The psychological tests include: ecological momentary assessment, P1vital Oxford Emotional Test Battery and Emotional Potentiated Startle Test, Leeds Sleep Evaluation Questionnaire and the visual working memory task (n-back). The neuroimaging protocol combines magnetic resonance sequences that capture data related to the functional and perfusion status of the brain. Discussion Results of this clinical trial are designed to evaluate the impact (with possible mechanistic insights) of different patterns of daily glucocorticoid dynamics on neural processing and reactivity related to emotional perception and mood. This evidence should contribute to the optimisation of the clinical application of glucocorticoid-based therapeutics. Trial registration UK Clinical Research Network, IRAS Ref: 106181, UKCRN-ID-15236 (23 October 2013)
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Affiliation(s)
- Konstantinos Kalafatakis
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, School of Clinical Sciences, Faculty of Medicine and Dentistry, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol, BS1 3NY, UK. .,Bristol Royal Infirmary, University Hospitals Bristol NHS Foundation Trust, Bristol, BS28HW, UK. .,Clinical Research and Imaging Centre, University of Bristol, Bristol, BS28DX, UK.
| | - Georgina M Russell
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, School of Clinical Sciences, Faculty of Medicine and Dentistry, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol, BS1 3NY, UK. .,Bristol Royal Infirmary, University Hospitals Bristol NHS Foundation Trust, Bristol, BS28HW, UK.
| | - Catherine J Harmer
- Department of Psychiatry, Medical Sciences Division, University of Oxford, Oxford, OX37JX, UK.
| | - Marcus R Munafo
- MRC Integrative Epidemiology Unit at the University of Bristol, UK Centre for Tobacco and Alcohol Studies, School of Experimental Psychology, University of Bristol, Bristol, BS81TU, UK.
| | - Nicky Marchant
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, School of Clinical Sciences, Faculty of Medicine and Dentistry, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol, BS1 3NY, UK. .,Bristol Royal Infirmary, University Hospitals Bristol NHS Foundation Trust, Bristol, BS28HW, UK.
| | - Aileen Wilson
- Clinical Research and Imaging Centre, University of Bristol, Bristol, BS28DX, UK.
| | - Jonathan C W Brooks
- Clinical Research and Imaging Centre, University of Bristol, Bristol, BS28DX, UK.
| | - Ngoc J Thai
- Clinical Research and Imaging Centre, University of Bristol, Bristol, BS28DX, UK.
| | - Stuart G Ferguson
- School of Medicine, University of Tasmania, Hobart, TAS 7000, Australia.
| | - Kirsty Stevenson
- Bristol Royal Infirmary, University Hospitals Bristol NHS Foundation Trust, Bristol, BS28HW, UK.
| | - Claire Durant
- Clinical Research and Imaging Centre, University of Bristol, Bristol, BS28DX, UK.
| | - Kristin Schmidt
- Department of Psychiatry, Medical Sciences Division, University of Oxford, Oxford, OX37JX, UK.
| | - Stafford L Lightman
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, School of Clinical Sciences, Faculty of Medicine and Dentistry, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol, BS1 3NY, UK. .,Bristol Royal Infirmary, University Hospitals Bristol NHS Foundation Trust, Bristol, BS28HW, UK.
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Kalafatakis K, Russell GM, Zarros A, Lightman SL. Temporal control of glucocorticoid neurodynamics and its relevance for brain homeostasis, neuropathology and glucocorticoid-based therapeutics. Neurosci Biobehav Rev 2015; 61:12-25. [PMID: 26656793 DOI: 10.1016/j.neubiorev.2015.11.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 10/09/2015] [Accepted: 11/19/2015] [Indexed: 11/26/2022]
Abstract
Glucocorticoids mediate plethora of actions throughout the human body. Within the brain, they modulate aspects of immune system and neuroinflammatory processes, interfere with cellular metabolism and viability, interact with systems of neurotransmission and regulate neural rhythms. The influence of glucocorticoids on memory and emotional behaviour is well known and there is increasing evidence for their involvement in many neuropsychiatric pathologies. These effects, which at times can be in opposing directions, depend not only on the concentration of glucocorticoids but also the duration of their presence, the temporal relationship between their fluctuations, the co-influence of other stimuli, and the overall state of brain activity. Moreover, they are region- and cell type-specific. The molecular basis of such diversity of effects lies on the orchestration of the spatiotemporal interplay between glucocorticoid- and mineralocorticoid receptors, and is achieved through complex dynamics, mainly mediated via the circadian and ultradian pattern of glucocorticoid secretion. More sophisticated methodologies are therefore required to better approach the study of these hormones and improve the effectiveness of glucocorticoid-based therapeutics.
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Affiliation(s)
- Konstantinos Kalafatakis
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, School of Clinical Sciences, Faculty of Medicine and Dentistry, University of Bristol, Bristol BS1 3NY, United Kingdom.
| | - Georgina M Russell
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, School of Clinical Sciences, Faculty of Medicine and Dentistry, University of Bristol, Bristol BS1 3NY, United Kingdom.
| | - Apostolos Zarros
- Research Department of Pharmaceutics, UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, United Kingdom.
| | - Stafford L Lightman
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, School of Clinical Sciences, Faculty of Medicine and Dentistry, University of Bristol, Bristol BS1 3NY, United Kingdom.
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Russell GM, Kalafatakis K, Lightman SL. The importance of biological oscillators for hypothalamic-pituitary-adrenal activity and tissue glucocorticoid response: coordinating stress and neurobehavioural adaptation. J Neuroendocrinol 2015; 27:378-88. [PMID: 25494867 PMCID: PMC4539599 DOI: 10.1111/jne.12247] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 11/26/2014] [Accepted: 12/10/2014] [Indexed: 12/28/2022]
Abstract
The hypothalamic-pituitary-adrenal (HPA) axis is critical for life. It has a circadian rhythm that anticipates the metabolic, immunoregulatory and cognitive needs of the active portion of the day, and retains an ability to react rapidly to perceived stressful stimuli. The circadian variation in glucocorticoids is very 'noisy' because it is made up from an underlying approximately hourly ultradian rhythm of glucocorticoid pulses, which increase in amplitude at the peak of circadian secretion. We have shown that these pulses emerge as a consequence of the feedforward-feedback relationship between the actions of corticotrophin hormone (ACTH) on the adrenal cortex and of endogenous glucocorticoids on pituitary corticotrophs. The adrenal gland itself has adapted to respond preferentially to a digital signal of ACTH and has its own feedforward-feedback system that effectively amplifies the pulsatile characteristics of the incoming signal. Glucocorticoid receptor signalling in the body is also adapted to respond in a tissue-specific manner to oscillating signals of glucocorticoids, and gene transcriptional and behavioural responses depend on the pattern (i.e. constant or pulsatile) of glucocorticoid presentation. During major stressful activation of the HPA, there is a marked remodelling of the pituitary-adrenal interaction. The link between ACTH and glucocorticoid pulses is maintained, although there is a massive increase in the adrenal responsiveness to the ACTH signals.
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Affiliation(s)
- G M Russell
- Henry Wellcome Laboratories of Integrative Neuroscience and Endocrinology, School of Clinical Sciences, Faculty of Medicine and Dentistry, University of Bristol, Bristol, UK
| | - K Kalafatakis
- Henry Wellcome Laboratories of Integrative Neuroscience and Endocrinology, School of Clinical Sciences, Faculty of Medicine and Dentistry, University of Bristol, Bristol, UK
| | - S L Lightman
- Henry Wellcome Laboratories of Integrative Neuroscience and Endocrinology, School of Clinical Sciences, Faculty of Medicine and Dentistry, University of Bristol, Bristol, UK
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Gibbison B, Spiga F, Walker JJ, Russell GM, Stevenson K, Kershaw Y, Zhao Z, Henley D, Angelini GD, Lightman SL. Dynamic pituitary-adrenal interactions in response to cardiac surgery. Crit Care Med 2015; 43:791-800. [PMID: 25517478 DOI: 10.1097/ccm.0000000000000773] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVES To characterize the dynamics of the pituitary-adrenal interaction during the course of coronary artery bypass grafting both on and off pump. Since our data pointed to a major change in adrenal responsiveness to adrenocorticotropic hormone, we used a reverse translation approach to investigate the molecular mechanisms underlying this change in a rat model of critical illness. DESIGN CLINICAL STUDIES Prospective observational study. ANIMAL STUDIES Controlled experimental study. SETTING CLINICAL STUDIES Cardiac surgery operating rooms and critical care units. ANIMAL STUDIES University research laboratory. SUBJECTS CLINICAL STUDIES Twenty, male patients. ANIMAL STUDIES Adult, male Sprague-Dawley rats. INTERVENTIONS CLINICAL STUDIES Coronary artery bypass graft-both on and off pump. ANIMAL STUDIES Injection of either lipopolysaccharide or saline (controls) via a jugular vein cannula. MEASUREMENTS AND MAIN RESULTS CLINICAL STUDIES Blood samples were taken for 24 hours from placement of the first venous access. Cortisol and adrenocorticotropic hormone were measured every 10 and 60 minutes, respectively, and corticosteroid-binding globulin was measured at the beginning and end of the 24-hour period and at the end of operation. There was an initial rise in both levels of adrenocorticotropic hormone and cortisol to supranormal values at around the end of surgery. Adrenocorticotropic hormone levels then returned toward preoperative values. Ultradian pulsatility of both adrenocorticotropic hormone and cortisol was maintained throughout the perioperative period in all individuals. The sensitivity of the adrenal gland to adrenocorticotropic hormone increased markedly at around 8 hours after surgery maintaining very high levels of cortisol in the face of "basal" levels of adrenocorticotropic hormone. This sensitivity began to return toward preoperative values at the end of the 24-hour sampling period. ANIMAL STUDIES Adult, male Sprague-Dawley rats were given either lipopolysaccharide or sterile saline via a jugular vein cannula. Hourly blood samples were subsequently collected for adrenocorticotropic hormone and corticosterone measurement. Rats were killed 6 hours after the injection, and the adrenal glands were collected for measurement of steroidogenic acute regulatory protein, steroidogenic factor 1, and dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1 messenger RNAs and protein using real-time quantitative polymerase chain reaction and Western immunoblotting, respectively. Adrenal levels of the adrenocorticotropic hormone receptor (melanocortin type 2 receptor) messenger RNA and its accessory protein (melanocortin type 2 receptor accessory protein) were also measured by real-time quantitative polymerase chain reaction. In response to lipopolysaccharide, rats showed a pattern of adrenocorticotropic hormone and corticosterone that was similar to patients undergoing coronary artery bypass grafting. We were also able to demonstrate increased intra-adrenal corticosterone levels and an increase in steroidogenic acute regulatory protein, steroidogenic factor 1, and melanocortin type 2 receptor accessory protein messenger RNAs and steroidogenic acute regulatory protein, and a reduction in dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1 and melanocortin type 2 receptor messenger RNAs, 6 hours after lipopolysaccharide injection. CONCLUSIONS Severe inflammatory stimuli activate the hypothalamic-pituitary-adrenal axis resulting in increased steroidogenic activity in the adrenal cortex and an elevation of cortisol levels in the blood. Following coronary artery bypass grafting, there is a massive increase in both adrenocorticotropic hormone and cortisol secretion. Despite a subsequent fall of adrenocorticotropic hormone to basal levels, cortisol remains elevated and coordinated adrenocorticotropic hormone-cortisol pulsatility is maintained. This suggested that there is an increase in adrenal sensitivity to adrenocorticotropic hormone, which we confirmed in our animal model of immune activation of the hypothalamic-pituitary-adrenal axis. Using this model, we were able to show that this increased adrenal sensitivity results from changes in the regulation of both stimulatory and inhibitory intra-adrenal signaling pathways. Increased understanding of the dynamics of normal hypothalamic-pituitary-adrenal responses to major surgery will provide us with a more rational approach to glucocorticoid therapy in critically ill patients.
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Affiliation(s)
- Ben Gibbison
- Department of Cardiac Anesthesia, Bristol Heart Institute, Bristol, UK.,Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, UK
| | - Francesca Spiga
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, UK
| | - Jamie J Walker
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, UK.,College of Engineering, Mathematics, and Physical Sciences, University of Exeter, Exeter, UK
| | - Georgina M Russell
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, UK
| | - Kirsty Stevenson
- Department of Clinical Biochemistry, University Hospitals Bristol NHS Foundation Trust, Bristol, UK
| | - Yvonne Kershaw
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, UK
| | - Zidong Zhao
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, UK
| | - David Henley
- Department of Endocrinology, Sir Charles Gairdner Hospital. Perth, WA. Australia.,Faculty of Medicine, Dentistry and Health Sciences. University of Western Australia, Crawley, WA, Australia
| | - Gianni D Angelini
- Department of Cardiac Surgery, Bristol Heart Institute, Bristol, UK.,National Heart and Lung Institute, Imperial College, London. UK
| | - Stafford L Lightman
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, UK
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Russell GM, Lightman SL. Can side effects of steroid treatments be minimized by the temporal aspects of delivery method? Expert Opin Drug Saf 2014; 13:1501-13. [DOI: 10.1517/14740338.2014.965141] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Russell GM, Durant C, Ataya A, Papastathi C, Bhake R, Woltersdorf W, Lightman S. Subcutaneous pulsatile glucocorticoid replacement therapy. Clin Endocrinol (Oxf) 2014; 81:289-93. [PMID: 24735400 PMCID: PMC4231230 DOI: 10.1111/cen.12470] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 04/05/2014] [Accepted: 04/11/2014] [Indexed: 11/29/2022]
Abstract
The glucocorticoid hormone cortisol is released in pulses resulting in a complex and dynamic ultradian rhythm of plasma cortisol that underlies the classical circadian rhythm. These oscillating levels are also seen at the level of tissues such as the brain and trigger pulses of gene activation and downstream signalling. Different patterns of glucocorticoid presentation (constant vs pulsatile) result not only in different patterns of gene regulation but also in different neuroendocrine and behavioural responses. Current 'optimal' glucocorticoid replacement therapy results in smooth hormone blood levels and does not replicate physiological pulsatile cortisol secretion. Validation of a novel portable pulsatile continuous subcutaneous delivery system in healthy volunteers under dexamethasone and metyrapone suppression. Pulsatile subcutaneous hydrocortisone more closely replicates physiological circadian and ultradian rhythmicity.
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Affiliation(s)
- Georgina M Russell
- Henry Wellcome Laboratories for Integrative Neurosciences and Endocrinology, Dorothy Hodgkin Building, University of BristolBristol, UK
| | - Claire Durant
- Henry Wellcome Laboratories for Integrative Neurosciences and Endocrinology, Dorothy Hodgkin Building, University of BristolBristol, UK
| | - Alia Ataya
- School of experimental psychology, University of BristolBristol, UK
| | - Chrysoula Papastathi
- Henry Wellcome Laboratories for Integrative Neurosciences and Endocrinology, Dorothy Hodgkin Building, University of BristolBristol, UK
| | - Ragini Bhake
- Henry Wellcome Laboratories for Integrative Neurosciences and Endocrinology, Dorothy Hodgkin Building, University of BristolBristol, UK
| | | | - Stafford Lightman
- Henry Wellcome Laboratories for Integrative Neurosciences and Endocrinology, Dorothy Hodgkin Building, University of BristolBristol, UK
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Henley DE, Russell GM, Douthwaite JA, Wood SA, Buchanan F, Gibson R, Woltersdorf WW, Catterall JR, Lightman SL. Hypothalamic-pituitary-adrenal axis activation in obstructive sleep apnea: the effect of continuous positive airway pressure therapy. J Clin Endocrinol Metab 2009; 94:4234-42. [PMID: 19820009 DOI: 10.1210/jc.2009-1174] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [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: 02/11/2023]
Abstract
CONTEXT Obstructive sleep apnea (OSA) is a common condition with significant cardiovascular and metabolic comorbidity. We hypothesized that these may result from OSA-induced perturbations of endogenous ultradian hypothalamic-pituitary-adrenal axis activity. OBJECTIVE The aim of the study was to investigate ACTH and cortisol ultradian patterns using an automated, repetitive blood sampling technique. DESIGN Samples for ACTH and cortisol were collected from 10 patients with moderate to severe OSA under basal conditions, at 10-min intervals over 24 h, at diagnosis and 3 months after compliant continuous positive airway pressure (CPAP) therapy. Multiple-parameter deconvolution estimated specific measures of ACTH and cortisol pulsatile secretion from blood hormone concentrations. RESULTS Mean total ACTH and cortisol production were elevated pre-CPAP compared to post-CPAP (ACTH, 1459.8 +/- 123.0 vs. 808.1 +/- 97.9 pg/ml, P < 0.001; cortisol, 5748.9 +/- 364.9 vs. 3817.7 +/- 351.7 nmol/liter, P < 0.001) as were mean total pulsatile production (ACTH, 764.1 +/- 86.3 vs. 383.5 +/- 50.0 pg/ml, P = 0.002; cortisol, 4715.9 +/- 253.3 vs. 3227.7 +/- 258.8 nmol/liter, P < 0.001). ACTH and cortisol secretory burst mean half-duration were higher at diagnosis (12.3 +/- 0.7 and 13.5 +/- 0.7 vs. 7.8 +/- 0.4 and 8.4 +/- 0.6 min, respectively, P < 0.001); thus, 95% of each ACTH secretion occurred in 21.0 +/- 1.2 vs. 12.9 +/- 0.8 min post-CPAP (P < 0.001) and for cortisol in 23.0 +/- 1.2 vs. 14.2 +/- 1.1 min post-CPAP (P < 0.001). Approximate entropy (ApEn) revealed greater disorderliness in both ACTH (P = 0.03) and cortisol (P = 0.001) time series pre-CPAP. Forward and reverse cross-ApEn suggested nodal disruption at central and adrenal levels pre-CPAP (P = 0.01). Significantly elevated cortisol responses to a single breath of 35% CO(2) occurred pre-CPAP (P = 0.006). CONCLUSIONS Untreated compared to treated OSA is associated with marked disturbances in ACTH and cortisol secretory dynamics, resulting in prolonged tissue exposure to disordered, elevated hormone levels.
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Affiliation(s)
- David E Henley
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol BS1 3NY, United Kingdom.
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Henley DE, Leendertz JA, Russell GM, Wood SA, Taheri S, Woltersdorf WW, Lightman SL. Development of an automated blood sampling system for use in humans. J Med Eng Technol 2009; 33:199-208. [PMID: 19340690 DOI: 10.1080/03091900802185970] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Many hormones are released in a pulsatile or burst-like pattern resulting in fluctuating blood levels that can undergo rapid modulation by physiological and pathological signals. To accurately measure these changes in hormone concentration requires frequent blood sampling, often over extended periods as the overall rhythmicity may vary over 24 hours. The aim of this study was to develop a computerized, automated blood sampling system which allows repeated stress-free blood sample collection from humans over an extended period under basal or test conditions. The system incorporates a peristaltic pump, fraction collector and standard infusion pump together with a custom built electronic control unit linked to a personal computer. Disposable tubing prevents cross-contamination between study participants. The computer programme is modifiable to adjust for the number of specimen tubes and volume of blood collected per sampling cycle. Patency of the collecting line is maintained with 0.9% saline, without the need for heparinization. To validate the system, 10-minute samples for cortisol were collected over 24 hours from five healthy volunteers, of whom two had additional concomitant ACTH sampling. Deconvolution analysis revealed an expected number of hormone secretory episodes and a non-pathological degree of orderliness within the data. There was high concordance between ACTH and cortisol secretory events. The ability of the system to allow multiple measurements and of the software program to link with other physiological monitoring equipment provides a powerful tool to study physiologic/pathophysiologic change in relation to blood hormone and other biomarker levels.
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Affiliation(s)
- D E Henley
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, UK.
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Lightman SL, Wiles CC, Atkinson HC, Henley DE, Russell GM, Leendertz JA, McKenna MA, Spiga F, Wood SA, Conway-Campbell BL. The significance of glucocorticoid pulsatility. Eur J Pharmacol 2008; 583:255-62. [DOI: 10.1016/j.ejphar.2007.11.073] [Citation(s) in RCA: 168] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2007] [Revised: 09/20/2007] [Accepted: 11/07/2007] [Indexed: 11/25/2022]
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Abstract
The 1985 outbreak of high-pathogenicity avian influenza (HPAI) in Victoria, Australia, took 5 days to confirm by standard laboratory tests, during which time infected chickens continued excreting virus, thus creating the opportunity for transmission to other farms. An immunofluorescence test for the detection of viral antigen in tissue impression smears was evaluated as a rapid diagnostic test for HPAI virus infections of poultry. Several test configurations were compared for background reactions and strength of fluorescence, with the optimum combination found to be an influenza A group-specific monoclonal antibody, detected by an anti-mouse fluorescein isothiocyanate conjugate. Immunohistochemical examination of tissues from chickens experimentally infected with low-pathogenicity and HPAI viruses identified the pancreas as the organ most consistently containing high concentrations of HPAI viral antigen. This test has since been used in Australia in the rapid laboratory confirmation of three avian influenza outbreaks and in showing that numerous other suspect cases were not caused by avian influenza.
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Affiliation(s)
- P W Selleck
- CSIRO Australian Animal Health Laboratory, 5 Portarlington Road, Geelong, 3220, Victoria, Australia
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Abstract
A human isolate of Nipah virus from an outbreak of febrile encephalitis in Malaysia that coincided with a field outbreak of disease in pigs was used to infect eight 6-week-old pigs orally or subcutaneously and two cats oronasally. In pigs, the virus induced a respiratory and neurological syndrome consistent with that observed in the Malaysian pigs. Not all the pigs showed clinical signs, but Nipah virus was recovered from the nose and oropharynx of both clinically and sub-clinically infected animals. Natural infection of in-contact pigs, which was readily demonstrated, appeared to be acute and self-limiting. Subclinical infections occurred in both inoculated and in-contact pigs. Respiratory and neurological disease was also produced in the cats, with recovery of virus from urine as well as from the oropharynx. The clinical and pathological syndrome induced by Nipah virus in cats was comparable with that associated with Hendra virus infection in this species, except that in fatal infection with Nipah virus there was extensive inflammation of the respiratory epithelium, associated with the presence of viral antigen. Viral shedding via the nasopharynx, as observed in pigs and cats in the present study, was not a regular feature of earlier reports of experimental Hendra virus infection in cats and horses. The findings indicate the possibility of field transmission of Nipah virus between pigs via respiratory and oropharyngeal secretions.
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Affiliation(s)
- D J Middleton
- Australian Animal Health Laboratory, CSIRO Livestock Industries, Geelong 3220, Australia
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Hooper PT, Russell GM, Selleck PW, Lunt RA, Morrissy CJ, Braun MA, Williamson MM. Immunohistochemistry in the identification of a number of new diseases in Australia. Vet Microbiol 1999; 68:89-93. [PMID: 10501165 DOI: 10.1016/s0378-1135(99)00064-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Immunohistochemistry plays an important part in the diagnosis of some viral diseases. Demonstration of viral antigen in a lesion is an important contribution to diagnosis, either at the time of investigation or retrospectively. At the CSIRO Australian Animal Health Laboratory, the most frequent use of immunohistochemistry has been in the diagnosis of the important avian diseases, highly pathogenic avian influenza and Newcastle disease. The technology took key roles in the diagnoses of Hendra virus infections, and, later, an immunoperoxidase test gave the first indication of the existence of Australian bat lyssavirus. The test can often confirm that a virus isolated in an animal is the actual virus causing disease and not a coincidental isolation. Good examples of that in some more new diseases were the association of Wallal virus with blindness in kangaroos, and of the new porcine Menangle virus in natural and experimental cerebral disease in foetal piglets.
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Affiliation(s)
- P T Hooper
- CSIRO Australian Animal Health Laboratory, Geelong.
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Hooper PT, Lunt RA, Gould AR, Hyatt AD, Russell GM, Kattenbelt JA, Blacksell SD, Reddacliff LA, Kirkland PD, Davis RJ, Durham PJ, Bishop AL, Waddington J. Epidemic of blindness in kangaroos--evidence of a viral aetiology. Aust Vet J 1999; 77:529-36. [PMID: 10494400 DOI: 10.1111/j.1751-0813.1999.tb12127.x] [Citation(s) in RCA: 30] [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: 11/28/2022]
Abstract
OBJECTIVE To determine the cause of an epidemic of blindness in kangaroos. DESIGN AND PROCEDURES Laboratory examinations were made of eyes and brains of a large number of kangaroos using serological, virological, histopathological, electron microscopical, immunohistochemical methods, and PCR with cDNA sequencing. In addition, potential insect viral vectors identified during the disease outbreak were examined for specific viral genomic sequences. SAMPLE POPULATION For histopathological analysis, 55 apparently blind and 18 apparently normal wild kangaroos and wallabies were obtained from New South Wales, Victoria, South Australia, and Western Australia. A total of 437 wild kangaroos and wallabies (including 23 animals with apparent blindness) were examined serologically. RESULTS Orbiviruses of the Wallal and Warrego serogroups were isolated from kangaroos affected with blindness in a major epidemic in south-eastern Australia in 1994 and 1995 and extending to Western Australia in 1995/96. Histopathological examinations showed severe degeneration and inflammation in the eyes, and mild inflammation in the brains. In affected retinas, Wallal virus antigen was detected by immunohistochemical analysis and orbiviruses were seen in electron microscopy. There was serological variation in the newly isolated Wallal virus from archival Wallal virus that had been isolated in northern Australia. There were also variations of up to 20% in genotype sequence from the reference archival virus. Polymerase chain reactions showed that Wallal virus was present during the epidemic in three species of midges, Culicoides austropalpalis, C dycei and C marksi. Wallal virus nucleic acid was also detected by PCR in a paraffin-embedded retina taken from a blind kangaroo in 1975. CONCLUSION Wallal virus and perhaps also Warrego virus are the cause of the outbreak of blindness in kangaroos. Other viruses may also be involved, but the evidence in this paper indicates a variant of Wallal virus, an orbivirus transmitted by midges, has the strongest aetiological association, and immunohistochemical analysis implicates it as the most damaging factor in the affected eyes.
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Affiliation(s)
- P T Hooper
- CSIRO Australian Animal Health Laboratory, Geelong, Victoria
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Affiliation(s)
- P T Hooper
- CSIRO Australian Animal Health Laboratory, Geelong, Victoria
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Hooper PT, Hansson E, Young JG, Russell GM, Della-Porta AJ. Lesions in the upper respiratory tract in chickens experimentally infected with Newcastle disease viruses isolated in Australia. Aust Vet J 1999; 77:50-1. [PMID: 10028397 DOI: 10.1111/j.1751-0813.1999.tb12432.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- P T Hooper
- CSIRO Australian Animal Health Laboratory, Geelong, Victoria
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Abstract
Nine cats and four guinea pigs became affected with severe disease during experiments on the infectivity of equine morbillivirus, a newly recognized cause of respiratory disease in horses and humans. Four of the cats were challenged by subcutaneous inoculation, two by intranasal installation, two by oral dosage, and one by direct contact with a cat previously infected by subcutaneous inoculation. All four guinea pigs were inoculated subcutaneously. Gross pathology seen in all affected cats was characterized by hydrothorax and dark, heavy, wet, congested and/or hemorrhagic lungs with froth sometimes found in the respiratory passages. Pulmonary lymph nodes were enlarged and edematous. Six cats also had congested ceca with accompanying edema of mesenteric lymph nodes. Histologically, the lesions in the lungs of the cats were those of severe interstitial pneumonia characterized by serofibrinous alveolar edema, alveolar macrophages, intra-alveolar hemorrhage, thrombosis of small veins, alveolar wall necrosis, and syncytial cells. Clearly defined vascular lesions included intramural hemorrhage, edema, and necrosis and syncytial cells in the endothelium of pulmonary arteries and veins, 20-80 microm in diameter. Vascular lesions accompanied by parenchymal degeneration were also seen in the gastrointestinal and lymphoid organs. Syncytial cells were also visible in the lymphoid tissues of lymph nodes, spleen, and Peyer's patches. At necropsy, all guinea pigs were cyanosed and had congestion and edema in the gastrointestinal tract. Histologically, there was widespread vascular disease in arteries and veins, 20-80 microm in diameter, in many organs such as the lungs, kidneys, spleens, lymph nodes, gastrointestinal tracts, and skeletal and intercostal muscles, but there was no severe pulmonary edema as seen in horses and cats. Sections of tissues of the cats and guinea pigs, examined by indirect immunocytochemical stains, confirmed that the vascular damage was associated with the presence of equine morbillivirus antigen. The syncytia in small blood vessels in the lungs and other organs of both cats and guinea pigs were similar to those seen in horses, and their presence was interpreted as an important characteristic of the disease consistent with a reaction to a morbillivirus.
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Affiliation(s)
- P T Hooper
- CSIRO Australian Animal Health Laboratory, Geelong.
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26
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Abstract
Laboratory examinations of equine morbillivirus included experimental reproductions of the disease caused by the virus by transmission of mixed lung and spleen taken from two field equine cases into two horses and by inoculating tissue culture virus into a further two horses. The most distinctive gross lesions of the diseases that developed in three of the horses was that of pulmonary edema characterized by gelatinous distension of subpleural lymphatics. Histologically, the lesions in the lungs were those of serofibrinous alveolar edema, alveolar macrophages, hemorrhage, thrombosis of capillaries, and syncytial cells. Clearly defined vascular lesions in three horses that became clinically affected within 8 days of inoculation of virus included intramural hemorrhage, edema, and necrosis and syncytial cells in the endothelium of pulmonary vessels (approximately 40-70 microm in diameter). Vascular lesions accompanied by parenchymal degeneration were also seen in the heart, kidney, brain, spleen, lymph node, and stomach. A fourth horse, which survived for 12 days, had detectable lesions only in the lungs, which were more chronic than those in the other three horses, a greater degree of cellular infiltration, and fewer well-defined vascular lesions. Sections stained by an indirect immunocytochemical method showed equine morbillivirus antigen was present in the vascular lesions and along alveolar walls. When endothelial cells were examined by electron microscope, cytoplasmic virus inclusion bodies containing filamentous structures were seen that reacted to an immunogold test to equine morbillivirus antigen. The presence of the syncytia in the small blood vessels in the lungs and other organs was interpreted as an important characteristic of the disease and consistent with a reaction to a morbillivirus.
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Affiliation(s)
- P T Hooper
- CSIRO Australian Animal Health Laboratory, Geelong.
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27
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Russell GM, Greenhouse EM. Homophobia in the supervisory relationship: an invisible intruder. Psychoanal Rev 1997; 84:27-42. [PMID: 9130321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- G M Russell
- Dept of Psychology, University of Colorado, Boulder, USA
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28
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Affiliation(s)
- P T Hooper
- CSIRO Australian Animal Health Laboratory, Geelong, Victoria
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29
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Fraser GC, Hooper PT, Lunt RA, Gould AR, Gleeson LJ, Hyatt AD, Russell GM, Kattenbelt JA. Encephalitis caused by a Lyssavirus in fruit bats in Australia. Emerg Infect Dis 1996; 2:327-31. [PMID: 8969249 PMCID: PMC2639915 DOI: 10.3201/eid0204.960408] [Citation(s) in RCA: 125] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
This report describes the first pathologic and immunohistochemical recognition in Australia of a rabies-like disease in a native mammal, a fruit bat, the black flying fox (Pteropus alecto). A virus with close serologic and genetic relationships to members of the Lyssavirus genus of the family Rhabdoviridae was isolated in mice from the tissue homogenates of a sick juvenile animal.
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Affiliation(s)
- G C Fraser
- NSW Department of Agriculture, Wollongbar, Australia
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30
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Russell GM, Mills AE. Pulmonary malakoplakia related to Rhodococcus equi occurring in the acquired immunodeficiency syndrome. Med J Aust 1994; 160:308-9. [PMID: 8107640] [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: 01/28/2023]
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31
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Russell GM, Kinirons MJ. The attitudes and experience of community dental officers in Northern Ireland in treating disabled people. Community Dent Health 1993; 10:327-33. [PMID: 8124620] [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: 01/28/2023]
Abstract
The views of community dental officers working in Northern Ireland were obtained concerning the difficulties they experience in treating disabled people. A closed questionnaire was used and a response rate of 84 per cent was achieved (60 officers). Thirty-seven per cent of the officers had received postgraduate training in this area. Lack of experience and knowledge concerning the treatment of the disabled was the commonest reason for not offering comprehensive dental care. Emotional upset and embarrassment or the length of time for treatment were the least cited. One-fifth perceived no barriers, a slight majority indicated two or less and only two officers indicated more than five. Those who were qualified ten years or longer, had greater difficulty than the more recently qualified in providing treatment for mentally and physically disabled children and medically compromised patients.
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Affiliation(s)
- G M Russell
- Department of Paediatric and Preventive Dentistry, School of Dentistry, Belfast, UK
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Russell GM, Kinirons MJ. A study of the barriers to dental care in a sample of patients with cerebral palsy. Community Dent Health 1993; 10:57-64. [PMID: 8495394] [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: 01/31/2023]
Abstract
The study examined the potential barriers to dental care for a selected sample of 57 adults suffering from cerebral palsy. The majority (60 per cent) were regular dental attenders and they received dental care in general dental practice and community dental practice in almost equal numbers. Those with mobility or communication difficulties were significantly more likely to attend the community or hospital dental services (P < 0.05). Their most common perceived barriers to dental care were fear, the need to be accompanied and negative attitudes, while cost was a rarely stated barrier. A dislike of dental treatment was significantly related to irregular attendance (P < 0.05) but neither anxiety nor the need to be accompanied were significantly related to attendance pattern.
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Affiliation(s)
- G M Russell
- Department of Paediatric and Preventive Dentistry, Queen's University of Belfast, UK
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Abstract
Ceftriaxone is a new, third-generation cephalosporin that, because of its long half-life, offers potential advantages of cost and convenience over similar agents such as cefotaxime. We compared the two drugs in a prospective, randomized study of the treatment of chest infections in seriously ill patients. Fifty-one patients (90 percent of whom were mechanically ventilated) received either ceftriaxone, 2g IV once daily, or cefotaxime, 2 g IV thrice daily, for five days. The two groups of patients appeared demographically comparable. Ceftriaxone in a single daily dose of 2 g once daily may not be satisfactory for the treatment of serious chest infections.
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Affiliation(s)
- J H Reeves
- Intensive Care Unit, Royal Melbourne Hospital, Victoria, Australia
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Abstract
Measures of discrepancy between observed behavior and that predicted by the Rotter (1966) I-E Scale indicate the usefulness of moderator variables in distinguishing defensive externality. To explore the complex relationship between verbalized beliefs and behavior a 26-item Behavioroid Internal-External Scale was developed and administered to 200 college students. Analysis of the scores indicated a symmetrical distribution, moderate to high loadings on a principal factor, moderate item-remainder correlations, and high reliability estimates. The validity and usefulness of the Behavioroid I-E Scale as a moderator variable were discussed.
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Russell GM, Schillings PH. Granuloma gangraenescens, a fatal disease of the face. Pract Otorhinolaryngol (Basel) 1966; 28:81-94. [PMID: 5920032 DOI: 10.1159/000274706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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