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Plomgaard AM, Stevenson N, Roberts JA, Hvass Petersen T, Vanhatalo S, Greisen G. Early EEG-burst sharpness and 2-year disability in extremely preterm infants. Pediatr Res 2024; 95:193-199. [PMID: 37500756 PMCID: PMC10798884 DOI: 10.1038/s41390-023-02753-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 06/17/2023] [Accepted: 07/07/2023] [Indexed: 07/29/2023]
Abstract
BACKGROUND Automated computational measures of EEG have the potential for large-scale application. We hypothesised that a predefined measure of early EEG-burst shape (increased burst sharpness) could predict neurodevelopmental impairment (NDI) and mental developmental index (MDI) at 2 years of age over-and-above that of brain ultrasound. METHODS We carried out a secondary analysis of data from extremely preterm infants collected for an RCT (SafeBoosC-II). Two hours of single-channel cross-brain EEG was used to analyse burst sharpness with an automated algorithm. The co-primary outcomes were moderate-or-severe NDI and MDI. Complete data were available from 58 infants. A predefined statistical analysis was adjusted for GA, sex and no, mild-moderate, and severe brain injury as detected by cranial ultrasound. RESULTS Nine infants had moderate-or-severe NDI and the mean MDI was 87 ± 17.3 SD. The typical burst sharpness was low (negative values) and varied relatively little (mean -0.81 ± 0.11 SD), but the odds ratio for NDI was increased by 3.8 (p = 0.008) and the MDI was reduced by -3.2 points (p = 0.14) per 0.1 burst sharpness units increase (+1 SD) in the adjusted analysis. CONCLUSION This study confirms the association between EEG-burst measures in preterm infants and neurodevelopment in childhood. Importantly, this was by a priori defined analysis. IMPACT A fully automated, computational measure of EEG in the first week of life was predictive of neurodevelopmental impairment at 2 years of age. This confirms many previous studies using expert reading of EEG. Only single-channel EEG data were used, adding to the applicability. EEG was recorded by several different devices thus this measure appears to be robust to differences in electrodes, amplifiers and filters. The likelihood ratio of a positive EEG test, however, was only about 2, suggesting little immediate clinical value.
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Affiliation(s)
- Anne Mette Plomgaard
- Department of Neonatology, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - Nathan Stevenson
- Brain Modelling Group, QIMR Berghofer Medical Research Institute, Herston, Brisbane, QLD, 4006, Australia
| | - James A Roberts
- Brain Modelling Group, QIMR Berghofer Medical Research Institute, Herston, Brisbane, QLD, 4006, Australia
| | | | - Sampsa Vanhatalo
- BABA Center, Departments of Clinical Neurophysiology and Physiology, Children's Hospital, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
| | - Gorm Greisen
- Department of Neonatology, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100, Copenhagen, Denmark.
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Sookplung P, Suchartwatnachai P, Akavipat P. The dosage of thiopental as pharmacological cerebral protection during non-shunt carotid endarterectomy: A retrospective study. F1000Res 2023; 12:381. [PMID: 38143589 PMCID: PMC10748806 DOI: 10.12688/f1000research.131838.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/05/2023] [Indexed: 12/26/2023] Open
Abstract
Background Thiopental has been used as a pharmacological cerebral protection strategy during carotid endarterectomy surgeries. However, the optimal dosage required to induce burst suppression on the electroencephalogram (EEG) remains unknown. This retrospective study aimed to determine the optimal dosage of thiopental required to induce burst suppression during non-shunt carotid endarterectomy. Methods The Neurological Institute of Thailand Review Board approved the study. Data were collected from 2009 to 2019 for all non-shunt carotid endarterectomy patients who received thiopental for pharmacological cerebral protection and had intraoperative EEG monitoring. Demographic information, carotid stenosis severity, intraoperative EEG parameters, thiopental dosage, carotid clamp time, intraoperative events, and patient outcomes were abstracted. Results The study included 57 patients. Among them, 24 patients (42%) achieved EEG burst suppression pattern with a thiopental dosage of 26.3±10.1 mg/kg/hr. There were no significant differences in perioperative events between patients who achieved burst suppression and those who did not. After surgery, 33.3% of patients who achieved burst suppression were extubated and awakened. One patient in the non-burst suppression group experienced mild neurological deficits. No deaths occurred within one month postoperative. Conclusions The optimal dosage of thiopental required to achieve burst suppression on intraoperative EEG during non-shunt carotid endarterectomy was 26.3±10.1 mg/kg/hr.
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Affiliation(s)
- Pimwan Sookplung
- Department of Anesthesiology, Neurological Institute of Thailand, Bangkok, 10400, Thailand
| | | | - Phuping Akavipat
- Department of Anesthesiology, Neurological Institute of Thailand, Bangkok, 10400, Thailand
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Alcock S, Singh S, Wiens EJ, Singh N, Ande SR, Lampron K, Huang B, Kirkpatrick I, Trivedi A, Schaffer SA, Shankar JS. CT perfusion for Assessment of poor Neurological outcome in Comatose Cardiac Arrest Patients (CANCCAP): protocol for a prospective study. BMJ Open 2023; 13:e071166. [PMID: 37270194 DOI: 10.1136/bmjopen-2022-071166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/05/2023] Open
Abstract
INTRODUCTION Cardiac arrest remains one of the most common causes of death with the majority occurring outside of hospitals (out of hospital cardiac arrest). Despite advancements in resuscitation management, approximately 50% of comatose cardiac arrest patients (CCAP) will suffer a severe unsurvivable brain injury. To assess brain injury, a neurological examination is conducted, however, its reliability in predicting outcomes in the first days following cardiac arrest is limited. Non-contrast CT is the most employed scan to assess hypoxic changes, even though it is not sensitive to early hypoxic-ischaemic changes in the brain. CT perfusion (CTP) has shown high sensitivity and specificity in brain death patients, although its use in predicting poor neurological outcome in CCAP has not yet been explored. The purpose of this study is to validate CTP for predicting poor neurological outcome (modified Rankin scale, mRS≥4) at hospital discharge in CCAP. METHODS AND ANALYSIS The CT Perfusion for Assessment of poor Neurological outcome in Comatose Cardiac Arrest Patients study is a prospective cohort study funded by the Manitoba Medical Research Foundation. Newly admitted CCAP receiving standard Targeted Temperature Management are eligible. Patients undergo a CTP at the same time as the admission standard of care head CT. Admission CTP findings will be compared with the reference standard of an accepted bedside clinical assessment at the time of admission. Deferred consent will be used. The primary outcome is a binary outcome of good neurological status, defined as mRs<4 or poor neurological status (mRs≥4) at hospital discharge. A total of 90 patients will be enrolled. ETHICS AND DISSEMINATION This study has been approved by the University of Manitoba Health Research Ethics Board. The findings from our study will be disseminated through peer-reviewed journals and presentations at local rounds, national and international conferences. The public will be informed at the end of the study. TRIAL REGISTRATION NUMBER NCT04323020.
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Affiliation(s)
- Susan Alcock
- Department of Radiology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Sarbjeet Singh
- Department of Radiology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Evan J Wiens
- Department of Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Navjit Singh
- University of Manitoba Max Rady College of Medicine, Winnipeg, Manitoba, Canada
| | - Sudharsana Rao Ande
- Department of Radiology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Kristen Lampron
- Department of Radiology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Beili Huang
- Department of Radiology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Iain Kirkpatrick
- Department of Radiology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Anurag Trivedi
- Section of Neurology, Department of Internal Medicine, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
| | - Stephen Allan Schaffer
- Sections of Cardiology and Critical Care Medicine, Department of Internal Medicine, University of Manitoba Max Rady College of Medicine, Winnipeg, Manitoba, Canada
| | - Jai Shiva Shankar
- Department of Radiology, University of Manitoba Max Rady College of Medicine, Winnipeg, Manitoba, Canada
- Department of Human Anatomy and Cell Science, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
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Zironi I, Aicardi G. Hypoxia Depresses Synaptic Transmission in the Primary Motor Cortex of the Infant Rat-Role of Adenosine A 1 Receptors and Nitric Oxide. Biomedicines 2022; 10:2875. [PMID: 36359395 PMCID: PMC9687150 DOI: 10.3390/biomedicines10112875] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/02/2022] [Accepted: 11/04/2022] [Indexed: 09/08/2024] Open
Abstract
The acute and long-term consequences of perinatal asphyxia have been extensively investigated, but only a few studies have focused on postnatal asphyxia. In particular, electrophysiological changes induced in the motor cortex by postnatal asphyxia have not been examined so far, despite the critical involvement of this cortical area in epilepsy. In this study, we exposed primary motor cortex slices obtained from infant rats in an age window (16-18 day-old) characterized by high incidence of hypoxia-induced seizures associated with epileptiform motor behavior to 10 min of hypoxia. Extracellular field potentials evoked by horizontal pathway stimulation were recorded in layers II/III of the primary motor cortex before, during, and after the hypoxic event. The results show that hypoxia reversibly depressed glutamatergic synaptic transmission and neuronal excitability. Data obtained in the presence of specific blockers suggest that synaptic depression was mediated by adenosine acting on pre-synaptic A1 receptors to decrease glutamate release, and by a nitric oxide (NO)/cGMP postsynaptic pathway. These effects are neuroprotective because they limit energy failure. The present findings may be helpful in the preclinical search for therapeutic strategies aimed at preventing acute and long-term neurological consequences of postnatal asphyxia.
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Affiliation(s)
- Isabella Zironi
- Department of Physics and Astronomy, University of Bologna, 40127 Bologna, Italy
| | - Giorgio Aicardi
- Department for Life Quality Studies, University of Bologna, 40127 Bologna, Italy
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Ni R, Müller Herde A, Haider A, Keller C, Louloudis G, Vaas M, Schibli R, Ametamey SM, Klohs J, Mu L. In vivo Imaging of Cannabinoid Type 2 Receptors: Functional and Structural Alterations in Mouse Model of Cerebral Ischemia by PET and MRI. Mol Imaging Biol 2022; 24:700-709. [PMID: 34642898 PMCID: PMC9581861 DOI: 10.1007/s11307-021-01655-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 09/09/2021] [Accepted: 09/14/2021] [Indexed: 02/07/2023]
Abstract
PURPOSE Stroke is one of the most prevalent vascular diseases. Non-invasive molecular imaging methods have the potential to provide critical insights into the temporal dynamics and follow alterations of receptor expression and metabolism in ischemic stroke. The aim of this study was to assess the cannabinoid type 2 receptor (CB2R) levels in transient middle cerebral artery occlusion (tMCAO) mouse models at subacute stage using positron emission tomography (PET) with our novel tracer [18F]RoSMA-18-d6 and structural imaging by magnetic resonance imaging (MRI). PROCEDURES Our recently developed CB2R PET tracer [18F]RoSMA-18-d6 was used for imaging neuroinflammation at 24 h after reperfusion in tMCAO mice. The RNA expression levels of CB2R and other inflammatory markers were analyzed by quantitative real-time polymerase chain reaction using brain tissues from tMCAO (1 h occlusion) and sham-operated mice. [18F]fluorodeoxyglucose (FDG) was included for evaluation of the cerebral metabolic rate of glucose (CMRglc). In addition, diffusion-weighted imaging and T2-weighted imaging were performed for anatomical reference and delineating the lesion in tMCAO mice. RESULTS mRNA expressions of inflammatory markers TNF-α, Iba1, MMP9 and GFAP, CNR2 were increased to 1.3-2.5 fold at 24 h after reperfusion in the ipsilateral compared to contralateral hemisphere of tMCAO mice, while mRNA expression of the neuronal marker MAP-2 was markedly reduced to ca. 50 %. Reduced [18F]FDG uptake was observed in the ischemic striatum of tMCAO mouse brain at 24 h after reperfusion. Although higher activity of [18F]RoSMA-18-d6 in ex vivo biodistribution studies and higher standard uptake value ratio (SUVR) were detected in the ischemic ipsilateral compared to contralateral striatum in tMCAO mice, the in vivo specificity of [18F]RoSMA-18-d6 was confirmed only in the CB2R-rich spleen. CONCLUSIONS This study revealed an increased [18F]RoSMA-18-d6 measure of CB2R and a reduced [18F]FDG measure of CMRglc in the ischemic striatum of tMCAO mice at subacute stage. [18F]RoSMA-18-d6 might be a promising PET tracer for detecting CB2R alterations in animal models of neuroinflammation without neuronal loss.
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Affiliation(s)
- Ruiqing Ni
- Institute for Biomedical Engineering, University of Zurich & ETH Zurich, Zurich, Switzerland
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
| | - Adrienne Müller Herde
- Department of Chemistry and Applied Biosciences, ETH Zurich, HCI H427 Vladimir-Prelog-Weg 1-5/10, 8093, Zurich, Switzerland
| | - Ahmed Haider
- Department of Chemistry and Applied Biosciences, ETH Zurich, HCI H427 Vladimir-Prelog-Weg 1-5/10, 8093, Zurich, Switzerland
| | - Claudia Keller
- Department of Chemistry and Applied Biosciences, ETH Zurich, HCI H427 Vladimir-Prelog-Weg 1-5/10, 8093, Zurich, Switzerland
| | - Georgios Louloudis
- Institute for Biomedical Engineering, University of Zurich & ETH Zurich, Zurich, Switzerland
| | - Markus Vaas
- Institute for Biomedical Engineering, University of Zurich & ETH Zurich, Zurich, Switzerland
| | - Roger Schibli
- Department of Chemistry and Applied Biosciences, ETH Zurich, HCI H427 Vladimir-Prelog-Weg 1-5/10, 8093, Zurich, Switzerland
| | - Simon M Ametamey
- Department of Chemistry and Applied Biosciences, ETH Zurich, HCI H427 Vladimir-Prelog-Weg 1-5/10, 8093, Zurich, Switzerland
| | - Jan Klohs
- Institute for Biomedical Engineering, University of Zurich & ETH Zurich, Zurich, Switzerland
| | - Linjing Mu
- Department of Chemistry and Applied Biosciences, ETH Zurich, HCI H427 Vladimir-Prelog-Weg 1-5/10, 8093, Zurich, Switzerland.
- Department of Nuclear Medicine, University Hospital Zurich, Zurich, Switzerland.
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Cerebral blood vessels and perfusion in the pediatric brain death: five cases studied by neuroimaging. Neuroradiology 2022; 64:1661-1669. [PMID: 35511244 DOI: 10.1007/s00234-022-02955-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 04/11/2022] [Indexed: 12/30/2022]
Abstract
PURPOSE To detect the cerebral blood vessels and perfusion using neuroimaging modalities including computed tomography angiography (CTA), computed tomography perfusion (CTP), and arterial spin labeling (ASL) in children with brain death (BD). METHODS According to the current children's BD criteria, 5 children (3 males, 2 females, mean age of 5.65 years) with BD were enrolled from January 2019 to December 2020. The imaging features of CTA, CTP, and ASL were evaluated to analyze the visualization of important intracranial blood vessels and the states of the cerebral blood flow (CBF) and cerebral blood volume (CBV) related to the region of interest (ROI) brain tissue during the two clinical assessments for BD. RESULTS The "4-point scale" scoring system of CTA was applied to evaluate BD and no negative results were detected. The CTP results of the 5 children suggested the cessation of cerebral circulation with 100% positive results. The ranges of CBF and CBV were 0.00-9.52 ml/100 g/min (mean value 4.95 ± 1.69 ml/100 g/min) and 0.00-1.34 ml/100 g (mean value 0.36 ± 0.20 ml/100 g), respectively. One patient also underwent ASL examination, which demonstrated a significant reduction in whole brain perfusion, indicating the absence of cerebral circulation. The CBF values of the brainstem, basal ganglia, and prefrontal lobe were 11.61 ± 1.49 ml/100 g/min, 7.81 ± 2.42 ml/100 g/min, and 9.94 ± 2.01 ml/100 g/min, respectively. CONCLUSION Neuroimaging examinations particularly CTA and CTP reveal well the hemodynamic and cerebral blood vessels changes of BD, which can be used as supplementary supportive evidence for the declaration of brain death in children.
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What Are We Measuring? A Refined Look at the Process of Disrupted Autoregulation and the Limitations of Cerebral Perfusion Pressure in Preventing Secondary Injury after Traumatic Brain Injury. Clin Neurol Neurosurg 2022; 221:107389. [PMID: 35961231 DOI: 10.1016/j.clineuro.2022.107389] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 07/19/2022] [Accepted: 07/25/2022] [Indexed: 11/23/2022]
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Effects of Citicoline on Structural/Functional Consequences of Focal Ischemia of the Rat Brain. NEUROPHYSIOLOGY+ 2022. [DOI: 10.1007/s11062-022-09918-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Powers WJ, An H, Diringer MN. Cerebral Blood Flow and Metabolism. Stroke 2022. [DOI: 10.1016/b978-0-323-69424-7.00003-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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10
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Roux SG, Garnier NB, Abry P, Gold N, Frasch MG. Distance to Healthy Metabolic and Cardiovascular Dynamics From Fetal Heart Rate Scale-Dependent Features in Pregnant Sheep Model of Human Labor Predicts the Evolution of Acidemia and Cardiovascular Decompensation. Front Pediatr 2021; 9:660476. [PMID: 34414140 PMCID: PMC8369259 DOI: 10.3389/fped.2021.660476] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 06/21/2021] [Indexed: 01/27/2023] Open
Abstract
The overarching goal of the present work is to contribute to the understanding of the relations between fetal heart rate (FHR) temporal dynamics and the well-being of the fetus, notably in terms of predicting the evolution of lactate, pH and cardiovascular decompensation (CVD). It makes uses of an established animal model of human labor, where 14 near-term ovine fetuses subjected to umbilical cord occlusions (UCO) were instrumented to permit regular intermittent measurements of metabolites lactate and base excess, pH, and continuous recording of electrocardiogram (ECG) and systemic arterial blood pressure (to identify CVD) during UCO. ECG-derived FHR was digitized at the sampling rate of 1,000 Hz and resampled to 4 Hz, as used in clinical routine. We focused on four FHR variability features which are tunable to temporal scales of FHR dynamics, robustly computable from FHR sampled at 4 Hz and within short-time sliding windows, hence permitting a time-dependent, or local, analysis of FHR which helps dealing with signal noise. Results show the sensitivity of the proposed features for early detection of CVD, correlation to metabolites and pH, useful for early acidosis detection and the importance of coarse time scales (2.5-8 s) which are not disturbed by the low FHR sampling rate. Further, we introduce the performance of an individualized self-referencing metric of the distance to healthy state, based on a combination of the four features. We demonstrate that this novel metric, applied to clinically available FHR temporal dynamics alone, accurately predicts the time occurrence of CVD which heralds a clinically significant degradation of the fetal health reserve to tolerate the trial of labor.
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Affiliation(s)
- Stephane G. Roux
- Laboratoire de Physique, Université Lyon, Ens de Lyon, Université Claude Bernard, CNRS, Lyon, France
| | - Nicolas B. Garnier
- Laboratoire de Physique, Université Lyon, Ens de Lyon, Université Claude Bernard, CNRS, Lyon, France
| | - Patrice Abry
- Laboratoire de Physique, Université Lyon, Ens de Lyon, Université Claude Bernard, CNRS, Lyon, France
| | - Nathan Gold
- Department of Mathematics and Statistics, York University, Toronto, ON, Canada
- Centre for Quantitative Analysis and Modelling, Fields Institute, Toronto, ON, Canada
| | - Martin G. Frasch
- Department of OBGYN, Center on Human Development and Disability, University of Washington, Seattle, WA, United States
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Alcock S, Batoo D, Ande SR, Grierson R, Essig M, Martin D, Trivedi A, Sinha N, Leeies M, Zeiler FA, Shankar JJS. Early diagnosis of mortality using admission CT perfusion in severe traumatic brain injury patients (ACT-TBI): protocol for a prospective cohort study. BMJ Open 2021; 11:e047305. [PMID: 34108167 PMCID: PMC8191612 DOI: 10.1136/bmjopen-2020-047305] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
INTRODUCTION Severe traumatic brain injury (TBI) is a catastrophic neurological condition with significant economic burden. Early in-hospital mortality (<48 hours) with severe TBI is estimated at 50%. Several clinical examinations exist to determine brain death; however, most are difficult to elicit in the acute setting in patients with severe TBI. Having a definitive assessment tool would help predict early in-hospital mortality in this population. CT perfusion (CTP) has shown promise diagnosing early in-hospital mortality in patients with severe TBI and other populations. The purpose of this study is to validate admission CTP features of brain death relative to the clinical examination outcome for characterizing early in-hospital mortality in patients with severe TBI. METHODS AND ANALYSIS The Early Diagnosis of Mortality using Admission CT Perfusion in Severe Traumatic Brain Injury Patients study, is a prospective cohort study in patients with severe TBI funded by a grant from the Canadian Institute of Health Research. Adults aged 18 or older, with evidence of a severe TBI (Glasgow Coma Scale score ≤8 before initial resuscitation) and, on mechanical ventilation at the time of imaging are eligible. Patients will undergo CTP at the time of first imaging on their hospital admission. Admission CTP compares with the reference standard of an accepted bedside clinical assessment for brainstem function. Deferred consent will be used. The primary outcome is a binary outcome of mortality (dead) or survival (not dead) in the first 48 hours of admission. The planned sample size for achieving a sensitivity of 75% and a specificity of 95% with a CI of ±5% is 200 patients. ETHICS AND DISSEMINATION This study has been approved by the University of Manitoba Health Research Ethics Board. The findings from our study will be disseminated through peer-reviewed journals and presentations at local rounds, national and international conferences. The public will be informed through forums at the end of the study. TRIAL REGISTRATION NUMBER NCT04318665.
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Affiliation(s)
- Susan Alcock
- Department of Radiology, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
| | - Divjeet Batoo
- Department of Radiology, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
| | - Sudharsana Rao Ande
- Department of Radiology, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
| | - Rob Grierson
- Department of Emergency Medicine, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
| | - Marco Essig
- Department of Radiology, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
| | - Douglas Martin
- Department of Emergency Medicine, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
| | - Anurag Trivedi
- Section of Neurology, Department of Internal Medicine, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
| | - Namita Sinha
- Section of Neuropathology, Department of Pathology, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
| | - Murdoch Leeies
- Department of Emergency Medicine & Section of Critical Care Medicine, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
| | - Frederick A Zeiler
- Section of Neurosurgery, Department of Surgery, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
- Department of Human Anatomy and Cell Science, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
| | - Jai Jai Shiva Shankar
- Department of Radiology, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
- Department of Human Anatomy and Cell Science, University of Manitoba Faculty of Health Sciences, Winnipeg, Manitoba, Canada
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Gold N, Herry CL, Wang X, Frasch MG. Fetal Cardiovascular Decompensation During Labor Predicted From the Individual Heart Rate Tracing: A Machine Learning Approach in Near-Term Fetal Sheep Model. Front Pediatr 2021; 9:593889. [PMID: 34026680 PMCID: PMC8132964 DOI: 10.3389/fped.2021.593889] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 03/31/2021] [Indexed: 12/26/2022] Open
Abstract
Background: When exposed to repetitive umbilical cord occlusions (UCO) with worsening acidemia, fetuses eventually develop cardiovascular decompensation manifesting as pathological hypotensive arterial blood pressure (ABP) responses to fetal heart rate (FHR) decelerations. Failure to maintain cardiac output during labor is a key event leading up to brain injury. We reported that the timing of the event when a fetus begins to exhibit this cardiovascular phenotype is highly individual and was impossible to predict. Objective: We hypothesized that this phenotype would be reflected in the individual behavior of heart rate variability (HRV) as measured by root mean square of successive differences of R-R intervals (RMSSD), a measure of vagal modulation of HRV, which is known to increase with worsening acidemia. This is clinically relevant because HRV can be computed in real-time intrapartum. Consequently, we aimed to predict the individual timing of the event when a hypotensive ABP pattern would emerge in a fetus from a series of continuous RMSSD data. Study Design: Fourteen near-term fetal sheep were chronically instrumented with vascular catheters to record fetal arterial blood pressure, umbilical cord occluder to mimic uterine contractions occurring during human labor and ECG electrodes to compute the ECG-derived HRV measure RMSSD. All animals were studied over a ~6 h period. After a 1-2 h baseline control period, the animals underwent mild, moderate, and severe series of repetitive UCO. We applied the recently developed machine learning algorithm to detect physiologically meaningful changes in RMSSD dynamics with worsening acidemia and hypotensive responses to FHR decelerations. To mimic clinical scenarios using an ultrasound-based 4 Hz FHR sampling rate, we recomputed RMSSD from FHR sampled at 4 Hz and compared the performance of our algorithm under both conditions (1,000 Hz vs. 4 Hz). Results: The RMSSD values were highly non-stationary, with four different regimes and three regime changes, corresponding to a baseline period followed by mild, moderate, and severe UCO series. Each time series was characterized by seemingly randomly occurring (in terms of timing of the individual onset) increase in RMSSD values at different time points during the moderate UCO series and at the start of the severe UCO series. This event manifested as an increasing trend in RMSSD values, which counter-intuitively emerged as a period of relative stationarity for the time series. Our algorithm identified these change points as the individual time points of cardiovascular decompensation with 92% sensitivity, 86% accuracy and 92% precision which corresponded to 14 ± 21 min before the visual identification. In the 4 Hz RMSSD time series, the algorithm detected the event with 3 times earlier detection times than at 1,000 Hz, i.e., producing false positive alarms with 50% sensitivity, 21% accuracy, and 27% precision. We identified the overestimation of baseline FHR variability by RMSSD at a 4 Hz sampling rate to be the cause of this phenomenon. Conclusions: The key finding is demonstration of FHR monitoring to detect fetal cardiovascular decompensation during labor. This validates the hypothesis that our HRV-based algorithm identifies individual time points of ABP responses to UCO with worsening acidemia by extracting change point information from the physiologically related fluctuations in the RMSSD signal. This performance depends on the acquisition accuracy of beat to beat fluctuations achieved in trans-abdominal ECG devices and fails at the sampling rate used clinically in ultrasound-based systems. This has implications for implementing such an approach in clinical practice.
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Affiliation(s)
- Nathan Gold
- Department of Mathematics and Statistics, York University, Toronto, ON, Canada
- Centre for Quantitative Analysis and Modelling, Fields Institute for Research in Mathematical Science, Toronto, ON, Canada
| | - Christophe L. Herry
- Dynamical Analysis Laboratory, Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Xiaogang Wang
- Department of Mathematics and Statistics, York University, Toronto, ON, Canada
- Institute of Big Data, Qing Hua University, Beijing, China
| | - Martin G. Frasch
- Department of Obstetrics and Gynecology and Center on Human Development and Disability, University of Washington, Seattle, WA, United States
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Greisen G, Hansen ML, Rasmussen MIS, Vestager M, Hyttel-Sørensen S, Hahn GH. Cerebral Oximetry in Preterm Infants-To Use or Not to Use, That Is the Question. Front Pediatr 2021; 9:747660. [PMID: 35186815 PMCID: PMC8847778 DOI: 10.3389/fped.2021.747660] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 12/28/2021] [Indexed: 12/19/2022] Open
Abstract
The Safeguarding the Brains of our smallest Children (SafeBoosC) project was initially established to test the patient-relevant benefits and harms of cerebral oximetry in extremely preterm infants in the setting of a randomized clinical trial. Extremely preterm infants constitute a small group of patients with a high risk of death or survival with brain injury and subsequent neurodevelopmental disability. Several cerebral oximeters are approved for clinical use, but the use of additional equipment may disturb and thereby possibly harm these vulnerable, immature patients. Thus, the mission statement of the consortium is "do not disturb-unless necessary." There may also be more tangible risks such as skin breakdown, displacement of tubes and catheters due to more complicated nursing care, and mismanagement of cerebral oxygenation as a physiological variable. Other monitoring modalities have relevance for reducing the risk of hypoxic-ischemic brain injury occurring during acute illness and have found their place in routine clinical care without evidence from randomized clinical trials. In this manuscript, we discuss cerebral oximetry, pulse oximetry, non-invasive electric cardiometry, and invasive monitoring of blood pressure. We discuss the reliability of the measurements, the pathophysiological rationale behind the clinical use, the evidence of benefit and harms, and the costs. By examining similarities and differences, we aim to provide our perspective on the use or non-use of cerebral oximetry in newborn infants during intensive care.
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Affiliation(s)
- Gorm Greisen
- Department of Neonatology, Rigshospitalet and Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Mathias Lühr Hansen
- Department of Neonatology, Rigshospitalet and Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Marie Isabel Skov Rasmussen
- Department of Neonatology, Rigshospitalet and Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Maria Vestager
- Department of Neonatology, Rigshospitalet and Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Simon Hyttel-Sørensen
- Department of Neonatology, Rigshospitalet and Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Gitte Holst Hahn
- Department of Neonatology, Rigshospitalet and Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
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VEGF/VEGFR-2 system exerts neuroprotection against Phoneutria nigriventer spider envenomation through PI3K-AKT-dependent pathway. Toxicon 2020; 185:76-90. [PMID: 32649934 DOI: 10.1016/j.toxicon.2020.06.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 06/23/2020] [Accepted: 06/23/2020] [Indexed: 01/19/2023]
Abstract
This study was undertaken to elucidate why VEGF/VEGFR-2 is elevated in the hippocampus of rats injected with Phoneutria nigriventer spider venom (PNV). PNV delays Na+ channels inactivation; blocks Ca2+ and K+ channels, increases glutamate release, causes blood-brain breakdown (BBBb), brain edema and severe excitotoxicity. Analytical FT-IR spectroscopy showed profound alteration in molecular biochemical state, with evidences for VEGFR-2 (KDR/Flk-1) signaling mediation. By blocking VEGF/VEGFR-2 binding via pre-treatment with itraconazole we demonstrated that animals' condition was deteriorated soon at 1-2 h post-PNV exposure concurrently with decreased expression of VEGF, BBB-associated proteins, ZO-1, β-catenin, laminin, P-gp (P-glycoprotein), Neu-N (neuron's viability marker) and MAPKphosphorylated-p38, while phosphorylated-ERK and Src pathways were increased. At 5 h and coinciding with incipient signs of animals' recuperation, the proteins associated with protection (HIF-1α, VEGF, VEGFR-1, VEGFR-2, Neu-N, occludin, β-catenin, laminin, P-gp efflux protein, phosphorylated-p38) increased thus indicating p38 pathway activation together with paracellular route strengthening. However, the BBB transcellular trafficking and caspase-3 increased (pro-apoptotic pathway activation). At 24 h, the transcellular route reestablished physiological state but the pro-survival pathway PI3K/(p-Akt) dropped in animals underwent VEGF/VEGFR-2 binding inhibition, whereas it was significantly activated at matched interval in PNV group without prior itraconazole; these results demonstrate impaired VEGF' survival effects at 24 h. The inhibition of VEGF/VEGFR-2 binding identified 5 h as turning point at which multi-level dynamic interplay was elicited to reverse hippocampal damage. Collectively, the data confirmed VEGFR-2 signaling via serine-threonine kinase Akt as neuroprotective pathway against PNV-induced damage. Further studies are needed to elucidate mechanisms underlying PNV effects.
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Nikolic D, Jankovic M, Petrovic B, Novakovic I. Genetic Aspects of Inflammation and Immune Response in Stroke. Int J Mol Sci 2020; 21:ijms21197409. [PMID: 33049931 PMCID: PMC7582307 DOI: 10.3390/ijms21197409] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 10/01/2020] [Accepted: 10/05/2020] [Indexed: 02/06/2023] Open
Abstract
Genetic determinants play important role in the complex processes of inflammation and immune response in stroke and could be studied in different ways. Inflammation and immunomodulation are associated with repair processes in ischemic stroke, and together with the concept of preconditioning are promising modes of stroke treatment. One of the important aspects to be considered in the recovery of patients after the stroke is a genetic predisposition, which has been studied extensively. Polymorphisms in a number of candidate genes, such as IL-6, BDNF, COX2, CYPC19, and GPIIIa could be associated with stroke outcome and recovery. Recent GWAS studies pointed to the variant in genesPATJ and LOC as new genetic markers of long term outcome. Epigenetic regulation of immune response in stroke is also important, with mechanisms of histone modifications, DNA methylation, and activity of non-coding RNAs. These complex processes are changing from acute phase over the repair to establishing homeostasis or to provoke exaggerated reaction and death. Pharmacogenetics and pharmacogenomics of stroke cures might also be evaluated in the context of immuno-inflammation and brain plasticity. Potential novel genetic treatment modalities are challenged but still in the early phase of the investigation.
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Affiliation(s)
- Dejan Nikolic
- Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia;
- Physical Medicine and Rehabilitation Department, University Children’s Hospital, 11000 Belgrade, Serbia
- Correspondence:
| | - Milena Jankovic
- Neurology Clinic, Clinical Center of Serbia, 11000 Belgrade, Serbia;
| | - Bojana Petrovic
- Clinic for Gynecology and Obstetrics, Clinical Center of Serbia, 11000 Belgrade, Serbia;
| | - Ivana Novakovic
- Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia;
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Martí-Carvajal AJ, Valli C, Martí-Amarista CE, Solà I, Martí-Fàbregas J, Bonfill Cosp X. Citicoline for treating people with acute ischemic stroke. Cochrane Database Syst Rev 2020; 8:CD013066. [PMID: 32860632 PMCID: PMC8406786 DOI: 10.1002/14651858.cd013066.pub2] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
BACKGROUND Stroke is one of the leading causes of long-lasting disability and mortality and its global burden has increased in the past two decades. Several therapies have been proposed for the recovery from, and treatment of, ischemic stroke. One of them is citicoline. This review assessed the benefits and harms of citicoline for treating patients with acute ischemic stroke. OBJECTIVES To assess the clinical benefits and harms of citicoline compared with placebo or any other control for treating people with acute ischemic stroke. SEARCH METHODS We searched in the Cochrane Stroke Group Trials Register, CENTRAL, MEDLINE Ovid, Embase Ovid, LILACS until 29 January 2020. We searched the World Health Organization Clinical Trials Search Portal and ClinicalTrials.gov. Additionally, we also reviewed reference lists of the retrieved publications and review articles, and searched the websites of the US Food and Drug Administration (FDA) and European Medicines Agency (EMA). SELECTION CRITERIA We included randomized controlled trials (RCTs) in any setting including participants with acute ischemic stroke. Trials were eligible for inclusion if they compared citicoline versus placebo or no intervention. DATA COLLECTION AND ANALYSIS We selected RCTs, assessed the risk of bias in seven domains, and extracted data by duplicate. Our primary outcomes of interest were all-cause mortality and the degree of disability or dependence in daily activities at 90 days. We estimated risk ratios (RRs) for dichotomous outcomes. We measured statistical heterogeneity using the I² statistic. We conducted our analyses using the fixed-effect and random-effects model meta-analyses. We assessed the overall quality of evidence for six pre-specified outcomes using the GRADE approach. MAIN RESULTS We identified 10 RCTs including 4281 participants. In all these trials, citicoline was given either orally, intravenously, or a combination of both compared with placebo or standard care therapy. Citicoline doses ranged between 500 mg and 2000 mg per day. We assessed all the included trials as having high risk of bias. Drug companies sponsored six trials. A pooled analysis of eight trials indicates there may be little or no difference in all-cause mortality comparing citicoline with placebo (17.3% versus 18.5%; RR 0.94, 95% CI 0.83 to 1.07; I² = 0%; low-quality evidence due to risk of bias). Four trials found no difference in the proportion of patients with disability or dependence in daily activities according to the Rankin scale comparing citicoline with placebo (21.72% versus 19.23%; RR 1.11, 95% CI 0.97 to 1.26; I² = 1%; low-quality evidence due to risk of bias). Meta-analysis of three trials indicates there may be little or no difference in serious cardiovascular adverse events comparing citicoline with placebo (8.83% versus 7.77%; RR 1.04, 95% CI 0.84 to 1.29; I² = 0%; low-quality evidence due to risk of bias). Overall, either serious or non-serious adverse events - central nervous system, gastrointestinal, musculoskeletal, etc. - were poorly reported and harms may have been underestimated. Four trials assessing functional recovery with the Barthel Index at a cut-off point of 95 points or more did not find differences comparing citicoline with placebo (32.78% versus 30.70%; RR 1.03, 95% CI 0.94 to 1.13; I² = 24%; low-quality evidence due to risk of bias). There were no differences in neurological function (National Institutes of Health Stroke Scale at a cut-off point of ≤ 1 points) comparing citicoline with placebo according to five trials (24.31% versus 22.44%; RR 1.08, 95% CI 0.96 to 1.21; I² = 27%, low-quality evidence due to risk of bias). A pre-planned Trial Sequential Analysis suggested that no more trials may be needed for the primary outcomes but no trial provided information on quality of life. AUTHORS' CONCLUSIONS This review assessed the clinical benefits and harms of citicoline compared with placebo or any other standard treatment for people with acute ischemic stroke. The findings of the review suggest there may be little to no difference between citicoline and its controls regarding all-cause mortality, disability or dependence in daily activities, severe adverse events, functional recovery and the assessment of the neurological function, based on low-certainty evidence. None of the included trials assessed quality of life and the safety profile of citicoline remains unknown. The available evidence is of low quality due to either limitations in the design or execution of the trials.
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Affiliation(s)
- Arturo J Martí-Carvajal
- Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE (Cochrane Ecuador), Quito, Ecuador
- School of Medicine, Universidad Francisco de Vitoria (Cochrane Madrid), Madrid, Spain
| | - Claudia Valli
- Iberoamerican Cochrane Centre, Biomedical Research Institute Sant Pau (IIB Sant Pau), Barcelona, Spain
| | | | - Ivan Solà
- Iberoamerican Cochrane Centre, Biomedical Research Institute Sant Pau (IIB Sant Pau), CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain
| | - Joan Martí-Fàbregas
- Unitat de Malalties Vasculars Cerebrals - Stroke Unit, Servei De Neurologia - Department of Neurology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Xavier Bonfill Cosp
- Iberoamerican Cochrane Centre, Biomedical Research Institute Sant Pau (IIB Sant Pau), Universitat Autònoma de Barcelona, CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain
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Castel A, Frank YS, Feltner J, Karp FB, Albright CM, Frasch MG. Monitoring Fetal Electroencephalogram Intrapartum: A Systematic Literature Review. Front Pediatr 2020; 8:584. [PMID: 33042922 PMCID: PMC7518218 DOI: 10.3389/fped.2020.00584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 08/07/2020] [Indexed: 12/05/2022] Open
Abstract
Background: Studies about the feasibility of monitoring fetal electroencephalogram (fEEG) during labor began in the early 1940s. By the 1970s, clear diagnostic and prognostic benefits from intrapartum fEEG monitoring were reported, but until today, this monitoring technology has remained a curiosity. Objectives: Our goal was to review the studies reporting the use of fEEG including the insights from interpreting fEEG patterns in response to uterine contractions during labor. We also used the most relevant information gathered from clinical studies to provide recommendations for enrollment in the unique environment of a labor and delivery unit. Data Sources: PubMed. Eligibility Criteria: The search strategy was: ("fetus"[MeSH Terms] OR "fetus"[All Fields] OR "fetal"[All Fields]) AND ("electroencephalography"[MeSH Terms] OR "electroencephalography"[All Fields] OR "eeg"[All Fields]) AND (Clinical Trial[ptyp] AND "humans"[MeSH Terms]). Because the landscape of fEEG research has been international, we included studies in English, French, German, and Russian. Results: From 256 screened studies, 40 studies were ultimately included in the qualitative analysis. We summarize and report features of fEEG which clearly show its potential to act as a direct biomarker of fetal brain health during delivery, ancillary to fetal heart rate monitoring. However, clinical prospective studies are needed to further establish the utility of fEEG monitoring intrapartum. We identified clinical study designs likely to succeed in bringing this intrapartum monitoring modality to the bedside. Limitations: Despite 80 years of studies in clinical cohorts and animal models, the field of research on intrapartum fEEG is still nascent and shows great promise to augment the currently practiced electronic fetal monitoring. Prospero Number: CRD42020147474.
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Affiliation(s)
- Aude Castel
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, Montreal, QC, Canada
| | - Yael S Frank
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA, United States
| | - John Feltner
- Department of Pediatrics, University of Washington, Seattle, WA, United States
| | - Floyd B Karp
- School of Pharmacy, University of Washington, Seattle, WA, United States
| | - Catherine M Albright
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA, United States
| | - Martin G Frasch
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA, United States.,Center on Human Development and Disability, University of Washington, Seattle, WA, United States
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Maternal nutrient restriction in guinea pigs leads to fetal growth restriction with increased brain apoptosis. Pediatr Res 2019; 85:105-112. [PMID: 30420709 DOI: 10.1038/s41390-018-0230-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 10/10/2018] [Accepted: 10/13/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND We determined whether maternal nutrient restriction (MNR) in guinea pigs leading to fetal growth restriction (FGR) impacts cell death in the brain with implications for neurodevelopmental adversity. METHODS Guinea pigs were fed ad libitum (Control) or 70% of the control diet before pregnancy, switching to 90% at mid-pregnancy (MNR). Fetuses were necropsied near term and brain tissues processed for necrosis (H&E), apoptosis (TUNEL), and pro- (Bax) and anti- (Bcl-2 and Grp78) apoptotic protein immunoreactivity. RESULTS FGR-MNR fetal and brain weights were decreased 38% and 12%, respectively, indicating brain sparing but with brains still smaller. While necrosis remained unchanged, apoptosis was increased in the white matter and hippocampus in the FGR brains, and control and FGR-related apoptosis were increased in males for most brain areas. Bax was increased in the CA4 and Bcl-2 was decreased in the dentate gyrus in the FGR brains supporting a role in the increased apoptosis, while Grp78 was increased in the FGR females, possibly contributing to the sex-related differences. CONCLUSIONS MNR-induced FGR results in increased brain apoptosis with regional and sex-related differences that may contribute to the reduction in brain area size reported clinically and increased risk in FGR males for later neurodevelopmental adversity.
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19
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Davidson SM, Arjun S, Basalay MV, Bell RM, Bromage DI, Bøtker HE, Carr RD, Cunningham J, Ghosh AK, Heusch G, Ibanez B, Kleinbongard P, Lecour S, Maddock H, Ovize M, Walker M, Wiart M, Yellon DM. The 10th Biennial Hatter Cardiovascular Institute workshop: cellular protection-evaluating new directions in the setting of myocardial infarction, ischaemic stroke, and cardio-oncology. Basic Res Cardiol 2018; 113:43. [PMID: 30310998 PMCID: PMC6182684 DOI: 10.1007/s00395-018-0704-z] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 10/04/2018] [Indexed: 12/13/2022]
Abstract
Due to its poor capacity for regeneration, the heart is particularly sensitive to the loss of contractile cardiomyocytes. The onslaught of damage caused by ischaemia and reperfusion, occurring during an acute myocardial infarction and the subsequent reperfusion therapy, can wipe out upwards of a billion cardiomyocytes. A similar program of cell death can cause the irreversible loss of neurons in ischaemic stroke. Similar pathways of lethal cell injury can contribute to other pathologies such as left ventricular dysfunction and heart failure caused by cancer therapy. Consequently, strategies designed to protect the heart from lethal cell injury have the potential to be applicable across all three pathologies. The investigators meeting at the 10th Hatter Cardiovascular Institute workshop examined the parallels between ST-segment elevation myocardial infarction (STEMI), ischaemic stroke, and other pathologies that cause the loss of cardiomyocytes including cancer therapeutic cardiotoxicity. They examined the prospects for protection by remote ischaemic conditioning (RIC) in each scenario, and evaluated impasses and novel opportunities for cellular protection, with the future landscape for RIC in the clinical setting to be determined by the outcome of the large ERIC-PPCI/CONDI2 study. It was agreed that the way forward must include measures to improve experimental methodologies, such that they better reflect the clinical scenario and to judiciously select combinations of therapies targeting specific pathways of cellular death and injury.
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Affiliation(s)
- Sean M Davidson
- The Hatter Cardiovascular Institute, Institute of Cardiovascular Science, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Sapna Arjun
- The Hatter Cardiovascular Institute, Institute of Cardiovascular Science, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Maryna V Basalay
- The Hatter Cardiovascular Institute, Institute of Cardiovascular Science, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Robert M Bell
- The Hatter Cardiovascular Institute, Institute of Cardiovascular Science, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Daniel I Bromage
- School of Cardiovascular Medicine and Sciences, King's College London British Heart Foundation Centre of Excellence, James Black Centre, 125 Coldharbour Lane, London, SE5 9NU, UK
| | - Hans Erik Bøtker
- Department of Cardiology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus N, Denmark
| | - Richard D Carr
- The Hatter Cardiovascular Institute, Institute of Cardiovascular Science, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
- MSD A/S, Copenhagen, Denmark
| | - John Cunningham
- Centre for Nephrology, UCL Medical School, Royal Free Campus, Rowland Hill Street, London, NW3 2PF, UK
| | - Arjun K Ghosh
- The Hatter Cardiovascular Institute, Institute of Cardiovascular Science, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Gerd Heusch
- West German Heart and Vascular Center, Institute for Pathophysiology, University of Essen Medical School, Essen, Germany
| | - Borja Ibanez
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- CIBER de Enfermedades CardioVasculares, Madrid, Spain
- IIS-Fundación Jiménez Díaz University Hospital, Madrid, Spain
| | - Petra Kleinbongard
- West German Heart and Vascular Center, Institute for Pathophysiology, University of Essen Medical School, Essen, Germany
| | - Sandrine Lecour
- Cardioprotection Group, Hatter Institute for Cardiovascular Research in Africa, University of Cape Town, Cape Town, South Africa
| | - Helen Maddock
- Centre for Sport, Exercise and Life Sciences, Faculty of Health and Life Sciences, Coventry University, Priory Street, Coventry, CV1 5FB, UK
| | - Michel Ovize
- INSERM U1060, CarMeN Laboratory, Université de Lyon and Service d'explorations Fonctionnelles Cardiovasculaires Groupement Hospitalier Est, 59 Boulevard Pinel, 69500, Bron, France
| | - Malcolm Walker
- The Hatter Cardiovascular Institute, Institute of Cardiovascular Science, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Marlene Wiart
- INSERM U1060, CarMeN Laboratory, Université de Lyon and Service d'explorations Fonctionnelles Cardiovasculaires Groupement Hospitalier Est, 59 Boulevard Pinel, 69500, Bron, France
- CNRS, Lyon, France
| | - Derek M Yellon
- The Hatter Cardiovascular Institute, Institute of Cardiovascular Science, University College London, 67 Chenies Mews, London, WC1E 6HX, UK.
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Abstract
Gaining insights into brain oxygen metabolism has been one of the key areas of research in neurosciences. Extensive efforts have been devoted to developing approaches capable of providing measures of brain oxygen metabolism not only under normal physiological conditions but, more importantly, in various pathophysiological conditions such as cerebral ischemia. In particular, quantitative measures of cerebral metabolic rate of oxygen using positron emission tomography (PET) have been shown to be capable of discerning brain tissue viability during ischemic insults. However, the complex logistics associated with oxygen-15 PET have substantially hampered its wide clinical applicability. In contrast, magnetic resonance imaging (MRI)-based approaches have provided quantitative measures of cerebral oxygen metabolism similar to that obtained using PET. Given the wide availability, MRI-based approaches may have broader clinical impacts, particularly in cerebral ischemia, when time is a critical factor in deciding treatment selection. In this article, we review the pathophysiological basis of altered cerebral hemodynamics and oxygen metabolism in cerebral ischemia, how quantitative measures of cerebral metabolism were obtained using the Kety-Schmidt approach, the physical concepts of non-invasive oxygen metabolism imaging approaches, and, finally, clinical applications of the discussed imaging approaches.
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Affiliation(s)
- Weili Lin
- 1 Biomedical Research Imaging Center and Department of Radiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,2 Department of Neurology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - William J Powers
- 2 Department of Neurology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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Martí-Carvajal AJ, Valli C, Solà I, Martí-Fàbregas J, Bonfill Cosp X. Citicoline for treating people with acute ischemic stroke. THE COCHRANE DATABASE OF SYSTEMATIC REVIEWS 2018. [DOI: 10.1002/14651858.cd013066] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
| | - Claudia Valli
- Hospital de la Santa Creu i Sant Pau, Universitat Autonoma de Barcelona; Iberoamerican Cochrane Centre; Barcelona Catalonia Spain 08026
| | - Ivan Solà
- CIBER Epidemiología y Salud Pública (CIBERESP); Iberoamerican Cochrane Centre, Biomedical Research Institute Sant Pau (IIB Sant Pau); Sant Antoni Maria Claret 167 Pavilion 18 Barcelona Catalunya Spain 08025
| | - Joan Martí-Fàbregas
- Hospital de la Santa Creu i Sant Pau; Unitat de Malalties Vasculars Cerebrals - Stroke Unit, Servei De Neurologia - Department of Neurology; Barcelona Catalonia Spain 08026
| | - Xavier Bonfill Cosp
- CIBER Epidemiología y Salud Pública (CIBERESP); Iberoamerican Cochrane Centre, Biomedical Research Institute Sant Pau (IIB Sant Pau); Sant Antoni Maria Claret 167 Pavilion 18 Barcelona Catalunya Spain 08025
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Wang H, He Z, Zhang Y, Zhang J. 1 H NMR metabolic signature of cerebrospinal fluid following repetitive lower-limb remote ischemia preconditioning. Neurochem Int 2018; 116:95-103. [DOI: 10.1016/j.neuint.2018.02.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 02/03/2018] [Accepted: 02/19/2018] [Indexed: 12/14/2022]
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Ni R, Vaas M, Ren W, Klohs J. Noninvasive detection of acute cerebral hypoxia and subsequent matrix-metalloproteinase activity in a mouse model of cerebral ischemia using multispectral-optoacoustic-tomography. NEUROPHOTONICS 2018; 5:015005. [PMID: 29531962 PMCID: PMC5829216 DOI: 10.1117/1.nph.5.1.015005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 01/12/2018] [Indexed: 05/03/2023]
Abstract
Oxygen metabolism and matrix metalloproteinases (MMPs) play important roles in the pathophysiology of cerebral ischemia. Using multispectral optoacoustic tomography (MSOT) imaging, we visualized in vivo changes in cerebral tissue oxygenation during 1 h of transient middle cerebral artery occlusion (tMCAO) and at 48 h after reperfusion together with MMP activity using an MMP-activatable probe. The deoxyhemoglobin, oxyhemoglobin, and MMP signals were coregistered with structural magnetic resonance imaging data. The ipsi-/contralateral ratio of tissue oxygen saturation ([Formula: see text]) was significantly reduced during 1 h of tMCAO and recovered after 48 h of reperfusion in tMCAO compared with sham-operated mice ([Formula: see text] to 10 per group). A higher ipsi-/contralateral MMP signal ratio was detected at 48 h after reperfusion in the lesioned brain regions of tMCAO compared with the sham-operated animal ([Formula: see text] to 6 per group). Ex vivo near-infrared fluorescence imaging of MMP signal in brain slices was used to validate in vivo MSOT measurements. In conclusion, noninvasive MSOT imaging can provide visualization of hemodynamic alterations and MMP activity in a mouse model of cerebral ischemia.
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Affiliation(s)
- Ruiqing Ni
- University of Zurich and ETH Zurich, Institute for Biomedical Engineering, Zurich, Switzerland
| | - Markus Vaas
- University of Zurich and ETH Zurich, Institute for Biomedical Engineering, Zurich, Switzerland
| | - Wuwei Ren
- University of Zurich and ETH Zurich, Institute for Biomedical Engineering, Zurich, Switzerland
| | - Jan Klohs
- University of Zurich and ETH Zurich, Institute for Biomedical Engineering, Zurich, Switzerland
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Zhang X, Wu F, Jiao Y, Tang T, Yang L, Lu C, Zhang Y, Zhang Y, Bai Y, Chao J, Teng G, Yao H. An Increase of Sigma-1 Receptor in the Penumbra Neuron after Acute Ischemic Stroke. J Stroke Cerebrovasc Dis 2017; 26:1981-1987. [PMID: 28687423 DOI: 10.1016/j.jstrokecerebrovasdis.2017.06.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 05/21/2017] [Accepted: 06/04/2017] [Indexed: 10/19/2022] Open
Abstract
BACKGROUND Penumbra salvage from infarction by early reperfusion within the time window is the target of acute ischemic stroke therapies. Although the penumbral imaging is potently usable in clinic trial, additional work needs to be performed to advancing the field with better-defined, evaluated, and validated imaging measures. METHODS Mice were subjected to permanent stroke by right middle cerebral artery (MCA) occlusion. Multimodel magnetic resonance imaging (MRI) method was assessed to define the penumbra as that brain region in which the perfusion and diffusion-weighted MR images are mismatched (perfusion-weighted imaging [PWI]-diffusion-weighted imaging [DWI] mismatch). MRI measurements were performed at 1 hour after MCA occlusion (MCAO). Sigma-1 receptor expression was assessed by immunoblotting and immunostaining in PWI-DWI-defined penumbra and core compared with sham or contralateral slice. Penumbral sigma-1 receptor identified the correlation with the neuron, astrocyte, and microglia by immuno-colocalization. RESULTS Sigma-1 receptor was significantly upregulated in penumbra or peri-infarct compared with sham and core tissue at 1 hour and 24 hours after MCAO. There was a colocalization of sigma-1 receptor and neuron in penumbra at 1 hour after stroke. Sigma-1 receptor is specifically increased in ischemic penumbral neuron at 1 hour after MCAO. CONCLUSIONS Sigma-1 receptor may act as an endogenous marker of penumbra after acute ischemic stroke.
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Affiliation(s)
- Xiaotian Zhang
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Fangfang Wu
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing, Jiangsu, China; Department of Neurology, Zhongda Hospital, Neuropsychiatric Institute, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Yun Jiao
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School of Southeast University, Nanjing, Jiangsu, China
| | - Tianyu Tang
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School of Southeast University, Nanjing, Jiangsu, China
| | - Li Yang
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Chunqiang Lu
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School of Southeast University, Nanjing, Jiangsu, China
| | - Yanhong Zhang
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Yuan Zhang
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Ying Bai
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Jie Chao
- Department of Physiology, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Gaojun Teng
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School of Southeast University, Nanjing, Jiangsu, China
| | - Honghong Yao
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing, Jiangsu, China; Institute of Life Sciences, Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing, Jiangsu, China.
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25
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Edmonds HL, Ganzel BL, Austin EH. Cerebral Oximetry for Cardiac and Vascular Surgery. Semin Cardiothorac Vasc Anesth 2017; 8:147-66. [PMID: 15248000 DOI: 10.1177/108925320400800208] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The technology of transcranial near-infrared spectroscopy (NIRS) for the measurement of cerebral oxygen balance was introduced 25 years ago. Until very recently, there has been only occasional interest in its use during surgical monitoring. Now, however, substantial technologic advances and numerous clinical studies have, at least partly, succeeded in overcoming long-standing and widespread misunderstanding and skepticism regarding its value. Our goals are to clarify common misconceptions about near-infrared spectroscopy and acquaint the reader with the substantial literature that now supports cerebral oximetric monitoring in cardiac and major vascular surgery.
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Affiliation(s)
- Harvey L Edmonds
- Department of Anesthesiology and Perioperative Medicine, University of Louisville School of Medicine, Louisville, Kentucky 40202-3619, USA.
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Saggu R. Interleukin-1beta-induced reduction of tissue water diffusion in the juvenile rat brain on ADC MRI is not associated with 31P MRS-detectable energy failure. J Inflamm (Lond) 2016; 13:9. [PMID: 26989349 PMCID: PMC4794816 DOI: 10.1186/s12950-016-0118-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 03/10/2016] [Indexed: 11/21/2022] Open
Abstract
Background It has long been known that an intrastriatal microinjection of the archetypal pro-inflammatory cytokine, interleukin-1beta (IL-1β), in juvenile rats induces a chronic reduction in the apparent diffusion coefficient (ADC) of tissue water on magnetic resonance imaging (MRI). Reduced ADC during acute cerebral ischaemia is an established indicator of metabolic failure whereas the cause of the IL-1β-induced reduction remains to be deciphered. Previously, it has been shown that IL-1β does not perturb the phosphorus (31P) magnetic resonance spectroscopy (MRS)-detectable energy status of an ex vivo preparation of rat brain parenchyma that is devoid of a functional vasculature component. However, brain energy status following an IL-1β challenge in vivo remains to be examined. Methods This study is the first longitudinal in vivo examination of the correlation of ADC MRI with localised 31P MRS signals obtained specifically from within the injected and non-injected striatum following IL-1β (1 ng/ul or 100 ng/ul) challenge, in real-time. Results Despite observing a chronic reduction in ADC at either dose of IL-1β challenge, energy compromise was not detected at any time point. Conclusions The IL-1β-induced effects pertaining to a functional vasculature such as leukocyte recruitment, blood–brain barrier (BBB) breakdown and blood flow changes are unlikely to impact on overall tissue energy status. Compared to classic ischaemia, there is dissociation between ADC and energy status within an IL-1β-induced lesion in vivo.
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27
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Turner RC, DiPasquale K, Logsdon AF, Tan Z, Naser ZJ, Huber JD, Rosen CL, Lucke-Wold BP. The role for infarct volume as a surrogate measure of functional outcome following ischemic stroke. JOURNAL OF SYSTEMS AND INTEGRATIVE NEUROSCIENCE 2016; 2. [PMID: 28299202 PMCID: PMC5347398 DOI: 10.15761/jsin.1000136] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The failed translation of proposed therapeutic agents for ischemic stroke from preclinical to clinical studies has led to increased scrutiny of preclinical studies, namely the model and outcome measures utilized. Preclinical studies routinely use infarct volume as an experimental endpoint or measure in studies employing young-adult, healthy male animals despite the fact that clinically, ischemic stroke is a disease of the elderly and improvements in functional outcome from pre- to post-intervention remains the most widely utilized assessment. The validity of infarct volume as a surrogate measure for functional outcome remains unclear in clinical studies as well as preclinical studies, particularly those utilizing a more clinically relevant aged thromboembolic model. In this work, we will address the relationship between acute and chronic functional outcome and infarct volume using a variety of functional assessments ranging from more simplistic, subjective measurements such as the modified Neurologic Severity Score (mNSS), to more complex, objective measurements such as grip strength and inclined plane.
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Affiliation(s)
- Ryan C Turner
- Department of Neurosurgery, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA; Center for Neuroscience, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Kenneth DiPasquale
- Center for Neuroscience, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA; Department of Basic Pharmaceutical Sciences, School of Pharmacy, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Aric F Logsdon
- Center for Neuroscience, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA; Department of Basic Pharmaceutical Sciences, School of Pharmacy, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Zhenjun Tan
- Department of Neurosurgery, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA; Center for Neuroscience, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Zachary J Naser
- Department of Neurosurgery, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA; Center for Neuroscience, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Jason D Huber
- Center for Neuroscience, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA; Department of Basic Pharmaceutical Sciences, School of Pharmacy, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Charles L Rosen
- Department of Neurosurgery, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA; Center for Neuroscience, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Brandon P Lucke-Wold
- Department of Neurosurgery, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA; Center for Neuroscience, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
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Abstract
Evidence from animal models of acute stroke suggests ischemia may be reversible if blood flow is restored in the first few hours. Studies of human stroke using posi tron emission tomography demonstrate areas with re duced blood flow and relatively preserved metabolism, indicating potentially reversible ischemic brain. Resto ration of blood flow during this reversible phase should improve outcome after stroke. Many therapeutic strategies for treatment of acute ischemic stroke have been proposed, including increas ing collateral flow, removing vascular obstructions, and interfering with the intracellular cascade of events that lead to neuronal cell death. Hypervolemic hemodilution reduces viscosity and increases cerebral blood flow, and this may hopefully raise blood flow above the critical threshold of irreversible ischemia. Naloxone, calcium channel blockers, and glutamate antagonists alter blood flow and influence intracellular events during and after acute ischemia. Thrombolytic therapy restores blood flow by lysis of obstructing clot. These therapies show promise in preliminary studies, but additional ran domized controlled studies are needed.
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Affiliation(s)
- Lawrence R. Wechsler
- From the University of Pittsburgh School of Medicine and the Clinical Stroke Service, Presbyterian-University Hospital, Pittsburgh, PA, Department of Neurology, 322 Scaife Hall, Pittsburgh, PA 15261
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29
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Cerebral Blood Flow and Metabolism. Stroke 2016. [DOI: 10.1016/b978-0-323-29544-4.00003-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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30
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Xu A, Matushewski B, Nygard K, Hammond R, Frasch MG, Richardson BS. Brain Injury and Inflammatory Response to Umbilical Cord Occlusions Is Limited With Worsening Acidosis in the Near-Term Ovine Fetus. Reprod Sci 2015; 23:858-70. [DOI: 10.1177/1933719115623640] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Alex Xu
- Department of Obstetrics and Gynecology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
| | - Brad Matushewski
- Department of Obstetrics and Gynecology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
| | - Karen Nygard
- Biotron Experimental Climate Change Research Centre, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
| | - Robert Hammond
- Department of Pathology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
| | - Martin G. Frasch
- Department of Obstetrics and Gynaecology and Department of Neurosciences, CHU Ste-Justine Research Center, Université de Montréal, Montreal, Québec, Canada
- Centre de Recherche en Reproduction Animale, Université de Montréal, St-Hyacinthe, Québec, Canada
| | - Bryan S. Richardson
- Department of Obstetrics and Gynecology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
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Frasch MG, Durosier LD, Gold N, Cao M, Matushewski B, Keenliside L, Louzoun Y, Ross MG, Richardson BS. Adaptive shut-down of EEG activity predicts critical acidemia in the near-term ovine fetus. Physiol Rep 2015; 3:3/7/e12435. [PMID: 26149280 PMCID: PMC4552521 DOI: 10.14814/phy2.12435] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
In fetal sheep, the electrocorticogram (ECOG) recorded directly from the cortex during repetitive heart rate (FHR) decelerations induced by umbilical cord occlusions (UCO) predictably correlates with worsening hypoxic-acidemia. In human fetal monitoring during labor, the equivalent electroencephalogram (EEG) can be recorded noninvasively from the scalp. We tested the hypothesis that combined fetal EEG – FHR monitoring allows for early detection of worsening hypoxic-acidemia similar to that shown for ECOG-FHR monitoring. Near-term fetal sheep (n = 9) were chronically instrumented with arterial and venous catheters, ECG, ECOG, and EEG electrodes and umbilical cord occluder, followed by 4 days of recovery. Repetitive UCOs of 1 min duration and increasing strength (with regard to the degree of reduction in umbilical blood flow) were induced each 2.5 min until pH dropped to <7.00. Repetitive UCOs led to marked acidosis (arterial pH 7.35 ± 0.01 to 7.00 ± 0.03). At pH of 7.22 ± 0.03 (range 7.32–7.07), and 45 ± 9 min (range 1 h 33 min–20 min) prior to attaining pH < 7.00, both ECOG and EEG amplitudes began to decrease ∼fourfold during each FHR deceleration in a synchronized manner. Confirming our hypothesis, these findings support fetal EEG as a useful adjunct to FHR monitoring during human labor for early detection of incipient fetal acidemia.
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Affiliation(s)
- Martin G Frasch
- Department of Obstetrics and Gynaecology, Department of Neurosciences, CHU Ste-Justine Research Center Université de Montréal, Montreal, Quebec, Canada
| | - Lucien Daniel Durosier
- Department of Obstetrics and Gynaecology, Department of Neurosciences, CHU Ste-Justine Research Center Université de Montréal, Montreal, Quebec, Canada
| | - Nathan Gold
- Department of Mathematics and Statistics, York University, Toronto, Ontario, Canada
| | - Mingju Cao
- Department of Obstetrics and Gynaecology, Department of Neurosciences, CHU Ste-Justine Research Center Université de Montréal, Montreal, Quebec, Canada
| | - Brad Matushewski
- Department of Obstetrics and Gynecology, University Western Ontario, London, Ontario, Canada
| | - Lynn Keenliside
- Imaging Program Lawson Health Research Institute, London, Ontario, Canada
| | - Yoram Louzoun
- Department of Mathematics, Bar-Ilan University, Ramat-Gan, Israel
| | - Michael G Ross
- Department of Obstetrics & Gynecology, LA BioMed at Harbor-UCLA Medical Center, Torrance, California
| | - Bryan S Richardson
- Department of Obstetrics and Gynecology, University Western Ontario, London, Ontario, Canada
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Kang KM, Yun TJ, Yoon BW, Jeon BS, Choi SH, Kim JH, Kim JE, Sohn CH, Han MH. Clinical utility of arterial spin-labeling as a confirmatory test for suspected brain death. AJNR Am J Neuroradiol 2015; 36:909-14. [PMID: 25572951 DOI: 10.3174/ajnr.a4209] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 11/11/2014] [Indexed: 01/03/2023]
Abstract
Diagnosis of brain death is made on the basis of 3 essential findings: coma, absence of brain stem reflexes, and apnea. Although confirmatory tests are not mandatory in most situations, additional testing may be necessary to declare brain death in patients in whom results of specific components of clinical testing cannot be reliably evaluated. Recently, arterial spin-labeling has been incorporated as part of MR imaging to evaluate cerebral perfusion. Advantages of arterial spin-labeling include being completely noninvasive and providing information about absolute CBF. We retrospectively reviewed arterial spin-labeling findings according to the following modified criteria based on previously established confirmatory tests to determine brain death: 1) extremely decreased perfusion in the whole brain, 2) bright vessel signal intensity around the entry of the carotid artery to the skull, 3) patent external carotid circulation, and 4) "hollow skull sign" in a series of 5 patients. Arterial spin-labeling findings satisfied the criteria for brain death in all patients. Arterial spin-labeling imaging has the potential to be a completely noninvasive confirmatory test to provide additional information to assist in the diagnosis of brain death.
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Affiliation(s)
- K M Kang
- From the Institute of Radiation Medicine (K.M.K., T.J.Y., S.H.C., J.-h.K., C.-H.S., M.H.H.), Seoul National University Medical Research Center, Seoul, Republic of Korea Departments of Radiology (K.M.K., T.J.Y., S.H.C., J.-h.K., C.-H.S., M.H.H.)
| | - T J Yun
- From the Institute of Radiation Medicine (K.M.K., T.J.Y., S.H.C., J.-h.K., C.-H.S., M.H.H.), Seoul National University Medical Research Center, Seoul, Republic of Korea Departments of Radiology (K.M.K., T.J.Y., S.H.C., J.-h.K., C.-H.S., M.H.H.)
| | - B-W Yoon
- Neurology (B.-W.Y., B.S.J.) Clinical Research Center for Stroke (B.-W.Y., B.S.J.), Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
| | - B S Jeon
- Neurology (B.-W.Y., B.S.J.) Clinical Research Center for Stroke (B.-W.Y., B.S.J.), Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
| | - S H Choi
- From the Institute of Radiation Medicine (K.M.K., T.J.Y., S.H.C., J.-h.K., C.-H.S., M.H.H.), Seoul National University Medical Research Center, Seoul, Republic of Korea Departments of Radiology (K.M.K., T.J.Y., S.H.C., J.-h.K., C.-H.S., M.H.H.)
| | - J-H Kim
- From the Institute of Radiation Medicine (K.M.K., T.J.Y., S.H.C., J.-h.K., C.-H.S., M.H.H.), Seoul National University Medical Research Center, Seoul, Republic of Korea Departments of Radiology (K.M.K., T.J.Y., S.H.C., J.-h.K., C.-H.S., M.H.H.)
| | | | - C-H Sohn
- From the Institute of Radiation Medicine (K.M.K., T.J.Y., S.H.C., J.-h.K., C.-H.S., M.H.H.), Seoul National University Medical Research Center, Seoul, Republic of Korea Departments of Radiology (K.M.K., T.J.Y., S.H.C., J.-h.K., C.-H.S., M.H.H.)
| | - M H Han
- From the Institute of Radiation Medicine (K.M.K., T.J.Y., S.H.C., J.-h.K., C.-H.S., M.H.H.), Seoul National University Medical Research Center, Seoul, Republic of Korea Departments of Radiology (K.M.K., T.J.Y., S.H.C., J.-h.K., C.-H.S., M.H.H.)
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An H, Ford AL, Chen Y, Zhu H, Ponisio R, Kumar G, Shanechi AM, Khoury N, Vo KD, Williams J, Derdeyn CP, Diringer MN, Panagos P, Powers WJ, Lee JM, Lin W. Defining the ischemic penumbra using magnetic resonance oxygen metabolic index. Stroke 2015; 46:982-8. [PMID: 25721017 DOI: 10.1161/strokeaha.114.008154] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Penumbral biomarkers promise to individualize treatment windows in acute ischemic stroke. We used a novel magnetic resonance imaging approach that measures oxygen metabolic index (OMI), a parameter closely related to positron emission tomography-derived cerebral metabolic rate of oxygen utilization (CMRO2), to derive a pair of ischemic thresholds: (1) an irreversible-injury threshold that differentiates ischemic core from penumbra and (2) a reversible-injury threshold that differentiates penumbra from tissue not-at-risk for infarction. METHODS Forty patients with acute ischemic stroke underwent magnetic resonance imaging at 3 time points after stroke onset: <4.5 hours (for OMI threshold derivation), 6 hours (to determine reperfusion status), and 1 month (for infarct probability determination). A dynamic susceptibility contrast method measured cerebral blood flow, and an asymmetrical spin echo sequence measured oxygen extraction fraction, to derive OMI (OMI=cerebral blood flow×oxygen extraction fraction). Putative ischemic threshold pairs were iteratively tested using a computation-intensive method to derive infarct probabilities in 3 tissue groups defined by the thresholds (core, penumbra, and not-at-risk tissue). An optimal threshold pair was chosen based on its ability to predict infarction in the core, reperfusion-dependent survival in the penumbra, and survival in not-at-risk tissue. The predictive abilities of the thresholds were then tested within the same cohort using a 10-fold cross-validation method. RESULTS The optimal OMI ischemic thresholds were found to be 0.28 and 0.42 of normal values in the contralateral hemisphere. Using the 10-fold cross-validation method, median infarct probabilities were 90.6% for core, 89.7% for nonreperfused penumbra, 9.95% for reperfused penumbra, and 6.28% for not-at-risk tissue. CONCLUSIONS OMI thresholds, derived using voxel-based, reperfusion-dependent infarct probabilities, delineated the ischemic penumbra with high predictive ability. These thresholds will require confirmation in an independent patient sample.
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Affiliation(s)
- Hongyu An
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.)
| | - Andria L Ford
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.)
| | - Yasheng Chen
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.)
| | - Hongtu Zhu
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.)
| | - Rosana Ponisio
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.)
| | - Gyanendra Kumar
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.)
| | - Amirali Modir Shanechi
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.)
| | - Naim Khoury
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.)
| | - Katie D Vo
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.)
| | - Jennifer Williams
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.)
| | - Colin P Derdeyn
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.)
| | - Michael N Diringer
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.)
| | - Peter Panagos
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.)
| | - William J Powers
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.)
| | - Jin-Moo Lee
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.).
| | - Weili Lin
- From the Biomedical Research Imaging Center and Departments of Radiology (H.A., Y.C., W.L.), Biostatistics (H.Z.), and Neurology (W.J.P., W.L.), University of North Carolina at Chapel Hill; Department of Neurology (A.L.F., G.K., N.K., J.-M.L.), Department of Radiology (R.P., K.D.V., C.P.D., J.-M.L.), Department of Emergency Medicine (P.P.), and School of Medicine (A.L.F., G.K., N.K., J.-M.L., R.P., K.D.V., C.P.D., J.-M.L., A.M.S., P.P.), Washington University, St. Louis, MO; and Emergency Department, Barnes-Jewish Hospital, St. Louis, MO (J.W.).
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Belpomme D, Campagnac C, Irigaray P. Reliable disease biomarkers characterizing and identifying electrohypersensitivity and multiple chemical sensitivity as two etiopathogenic aspects of a unique pathological disorder. REVIEWS ON ENVIRONMENTAL HEALTH 2015; 30:251-271. [PMID: 26613326 DOI: 10.1515/reveh-2015-0027] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 11/02/2015] [Indexed: 06/05/2023]
Abstract
Much of the controversy over the causes of electro-hypersensitivity (EHS) and multiple chemical sensitivity (MCS) lies in the absence of both recognized clinical criteria and objective biomarkers for widely accepted diagnosis. Since 2009, we have prospectively investigated, clinically and biologically, 1216 consecutive EHS and/or MCS-self reporting cases, in an attempt to answer both questions. We report here our preliminary data, based on 727 evaluable of 839 enrolled cases: 521 (71.6%) were diagnosed with EHS, 52 (7.2%) with MCS, and 154 (21.2%) with both EHS and MCS. Two out of three patients with EHS and/or MCS were female; mean age (years) was 47. As inflammation appears to be a key process resulting from electromagnetic field (EMF) and/or chemical effects on tissues, and histamine release is potentially a major mediator of inflammation, we systematically measured histamine in the blood of patients. Near 40% had a increase in histaminemia (especially when both conditions were present), indicating a chronic inflammatory response can be detected in these patients. Oxidative stress is part of inflammation and is a key contributor to damage and response. Nitrotyrosin, a marker of both peroxynitrite (ONOO°-) production and opening of the blood-brain barrier (BBB), was increased in 28% the cases. Protein S100B, another marker of BBB opening was increased in 15%. Circulating autoantibodies against O-myelin were detected in 23%, indicating EHS and MCS may be associated with autoimmune response. Confirming animal experiments showing the increase of Hsp27 and/or Hsp70 chaperone proteins under the influence of EMF, we found increased Hsp27 and/or Hsp70 in 33% of the patients. As most patients reported chronic insomnia and fatigue, we determined the 24 h urine 6-hydroxymelatonin sulfate (6-OHMS)/creatinin ratio and found it was decreased (<0.8) in all investigated cases. Finally, considering the self-reported symptoms of EHS and MCS, we serially measured the brain blood flow (BBF) in the temporal lobes of each case with pulsed cerebral ultrasound computed tomosphygmography. Both disorders were associated with hypoperfusion in the capsulothalamic area, suggesting that the inflammatory process involve the limbic system and the thalamus. Our data strongly suggest that EHS and MCS can be objectively characterized and routinely diagnosed by commercially available simple tests. Both disorders appear to involve inflammation-related hyper-histaminemia, oxidative stress, autoimmune response, capsulothalamic hypoperfusion and BBB opening, and a deficit in melatonin metabolic availability; suggesting a risk of chronic neurodegenerative disease. Finally the common co-occurrence of EHS and MCS strongly suggests a common pathological mechanism.
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Abstract
The neurological determination of death (NDD) is primarily considered to be clinical. However, situations may arise where confounding factors make this clinical assessment difficult or impossible. As a result, ancillary tests have been developed in order to aid in the confirmation of brain death. As assessment of neuronal electrical activity; electroencephalography (EEG) is no longer recommended in this determination, tools assessing cerebral perfusion, as reflected by the presence or absence of cerebral blood flow (CBF), are the mainstay of NDD. The preferred ancillary test currently is Hexamethylpropylene amine oxime-single photon emission computed tomography (HMPAO SPECT) radionuclide angiography. When this is not available, or is equivocal, 4-vessel cerebral angiography can be used to determine the presence or absence of intracranial blood flow. However, as cerebral angiography has its own limitations, other techniques are sought by physicians in the Intensive Care and Neuro-intensive Care settings to replace cerebral angiography. In this article, we briefly review the history of diagnosis of brain death, pathophysiologic issues in making this determination, and currently available CBF imaging techniques, discussing each in turn with respect to their utility in the diagnosis of brain death.
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Abstract
The ability to image the ischemic penumbra during hyper-acute stroke promises to identify patients who may benefit from treatment intervention beyond population-defined therapeutic time windows. MR blood oxygenation level dependent (BOLD) contrast imaging has been explored in ischemic stroke. This review provides an overview of several BOLD-based methods, including susceptibility weighted imaging (SWI), R2, R2*, R2', R2* under oxygen challenge, MR_OEF and MROMI approaches to assess cerebral oxygen metabolism in ischemic stroke. We will review the underlying pathophysiological basis of the imaging approaches, followed by a brief introduction of BOLD contrast. Finally, we will discuss the applications of the BOLD approaches in patients with ischemic stroke. BOLD-based methods hold promise for imaging tissue oxygenation during acute ischemia. Further technical refinement and validation studies in stroke patients against positron emission tomography (PET) measurements are needed.
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Davies AL, Desai RA, Bloomfield PS, McIntosh PR, Chapple KJ, Linington C, Fairless R, Diem R, Kasti M, Murphy MP, Smith KJ. Neurological deficits caused by tissue hypoxia in neuroinflammatory disease. Ann Neurol 2013; 74:815-25. [PMID: 24038279 DOI: 10.1002/ana.24006] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 07/29/2013] [Accepted: 08/03/2013] [Indexed: 01/07/2023]
Abstract
OBJECTIVE To explore the presence and consequences of tissue hypoxia in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). METHODS EAE was induced in Dark Agouti rats by immunization with recombinant myelin oligodendrocyte glycoprotein and adjuvant. Tissue hypoxia was assessed in vivo using 2 independent methods: an immunohistochemical probe administered intravenously, and insertion of a physical, oxygen-sensitive probe into the spinal cord. Indirect markers of tissue hypoxia (eg, expression of hypoxia-inducible factor-1α [HIF-1α], vessel diameter, and number of vessels) were also assessed. The effects of brief (1 hour) and continued (7 days) normobaric oxygen treatment on function were evaluated in conjunction with other treatments, namely administration of a mitochondrially targeted antioxidant (MitoQ) and inhibition of inducible nitric oxide synthase (1400W). RESULTS Observed neurological deficits were quantitatively, temporally, and spatially correlated with spinal white and gray matter hypoxia. The tissue expression of HIF-1α also correlated with loss of function. Spinal microvessels became enlarged during the hypoxic period, and their number increased at relapse. Notably, oxygen administration significantly restored function within 1 hour, with improvement persisting at least 1 week with continuous oxygen treatment. MitoQ and 1400W also caused a small but significant improvement. INTERPRETATION We present chemical, physical, immunohistochemical, and therapeutic evidence that functional deficits caused by neuroinflammation can arise from tissue hypoxia, consistent with an energy crisis in inflamed central nervous system tissue. The neurological deficit was closely correlated with spinal white and gray matter hypoxia. This realization may indicate new avenues for therapy of neuroinflammatory diseases such as MS.
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Affiliation(s)
- Andrew L Davies
- Department of Neuroinflammation, University College London Institute of Neurology, London, United Kingdom
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Bimpis A, Papalois A, Tsakiris S, Kalafatakis K, Zarros A, Gkanti V, Skandali N, Al-Humadi H, Kouzelis C, Liapi C. Modulation of crucial adenosinetriphosphatase activities due to U-74389G administration in a porcine model of intracerebral hemorrhage. Metab Brain Dis 2013; 28:439-46. [PMID: 23344690 DOI: 10.1007/s11011-013-9380-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Accepted: 01/11/2013] [Indexed: 10/27/2022]
Abstract
Spontaneous intracerebral hemorrhage (ICH) represents a partially-understood cerebrovascular disease of high incidence, morbidity and mortality. We, herein, report the findings of our study concerning the role of two important adenosinetriphosphatases (ATPases) in a porcine model of spontaneous ICH that we have recently developed (by following recent references as well as previously-established models and techniques), with a focus on the first 4 and 24 h following the lesion's induction, in combination with a study of the effectiveness of the lazaroid antioxidant U-74389G administration. Our study demonstrates that the examined ICH model does not cause a decrease in Na(+),K(+)-ATPase activity (the levels of which are responsible for a very large part of neuronal energy expenditure) in the perihematomal basal ganglia territory, nor a change in the activity of Mg(2+)-ATPase. This is the first report focusing on these crucial ATPases in the experimental setting of ICH and differs from the majority of the findings concerning the behavior of these (crucial for central nervous system cell survival) enzymes under stroke-related ischemic conditions. The administration of U-74389G (an established antioxidant) in this ICH model revealed an injury specific type of behavior, that could be considered as neuroprotective provided that one considers that Na(+),K(+)- and Mg(2+)-ATPase inhibition might in this case diminish the local ATP consumption.
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Affiliation(s)
- Alexios Bimpis
- Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
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Corcoran A, O'Connor JJ. Hypoxia-inducible factor signalling mechanisms in the central nervous system. Acta Physiol (Oxf) 2013; 208:298-310. [PMID: 23692777 DOI: 10.1111/apha.12117] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 04/01/2013] [Accepted: 05/16/2013] [Indexed: 12/22/2022]
Abstract
In the CNS, neurones are highly sensitive to the availability of oxygen. In conditions where oxygen availability is decreased, neuronal function can be altered, leading to injury and cell death. Hypoxia has been implicated in a number of central nervous system pathologies including stroke, head trauma and neurodegenerative diseases. Cellular responses to oxygen deprivation are complex and result in activation of short- and long-term mechanisms to conserve energy and protect cells. Failure of synaptic transmission can be observed within minutes following this hypoxia. The acute effects of hypoxia on synaptic transmission are primarily mediated by altering ion fluxes across membranes, pre-synaptic effects of adenosine and other actions at glutamatergic receptors. A more long-term feature of the response of neurones to hypoxia is the activation of transcription factors such as hypoxia-inducible factor. The activation of hypoxia-inducible factor is governed by a family of dioxygenases called hypoxia-inducible factor prolyl 4 hydroxylases (PHDs). Under hypoxic conditions, PHD activity is inhibited, thereby allowing hypoxia-inducible factor to accumulate and translocate to the nucleus, where it binds to the hypoxia-responsive element sequences of target gene promoters. Inhibition of PHD activity stabilizes hypoxia-inducible factor and other proteins thus acting as a neuroprotective agent. This review will focus on the response of neuronal cells to hypoxia-inducible factor and its targets, including the prolyl hydroxylases. We also present evidence for acute effects of PHD inhibition on synaptic transmission and plasticity in the hippocampus.
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Affiliation(s)
- A. Corcoran
- UCD School of Biomolecular and Biomedical Science; UCD Conway Institute of Biomolecular and Biomedical Research; UniversityCollege Dublin; Dublin; Ireland
| | - J. J. O'Connor
- UCD School of Biomolecular and Biomedical Science; UCD Conway Institute of Biomolecular and Biomedical Research; UniversityCollege Dublin; Dublin; Ireland
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Abstract
Oxygen is the proverbial 'double-edged sword' in that it is a necessity for life in moderation and toxic and detrimental to life in excess. This too is the dilemma in hyperbaric oxygen (HBO) treatment in cerebral ischemic-anoxic insults such as stroke, head injury, near drowning, asphyxia, cardiac arrest, etc., i.e. the brain at risk, where regions of ischemia are beside regions of marked hyperemia. The natural heterogeneity of normal brain tissue oxygenation compounds the problem with different microvascular brain regions living at various levels of oxygenation from 0 to arterial PO(2) as an added complication. The application of HBO, whether normobaric or hyperbaric, will result in brain tissue oxygenation ranging from normoxic to highly hyperoxic with the latter possibly exacerbating the injury sustained. On this basis, the application of multiple therapeutic interventions may be considered, for example, HBO in combination with free radical scavengers or inhibitors of free radical generating enzymes. Despite these difficulties in moderating oxygen delivery to treat cerebral ischemic-anoxic insults, overwhelming preclinical evidence indicates that HBO administered during or within 2 hours post-insult effectively attenuates the severity of brain damage sustained. The primary disconnection between pre-clinical and clinical efficacy of HBO then appears to be the time of application. Clinically, HBO therapy is applied at the earliest 6 hours post-insult but usually between 12 hours or longer post-insult. Pre-hospital application of HBO may be required for clear-cut demonstration of clinical efficacy.
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Affiliation(s)
- Edwin M Nemoto
- Department of Radiology, B-804 Presbyterian University Hospital, University of Pittsburgh, 200 Lothrop Street, Pittsburgh, PA 15213, USA
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Ionic transporter activity in astrocytes, microglia, and oligodendrocytes during brain ischemia. J Cereb Blood Flow Metab 2013; 33:969-82. [PMID: 23549380 PMCID: PMC3705429 DOI: 10.1038/jcbfm.2013.44] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 02/27/2013] [Accepted: 02/28/2013] [Indexed: 01/09/2023]
Abstract
Glial cells constitute a large percentage of cells in the nervous system. During recent years, a large number of studies have critically attributed to glia a new role which no longer reflects the long-held view that glia constitute solely a silent and passive supportive scaffolding for brain cells. Indeed, it has been hypothesized that glia, partnering neurons, have a much more actively participating role in brain function. Alteration of intraglial ionic homeostasis in response to ischemic injury has a crucial role in inducing and maintaining glial responses in the ischemic brain. Therefore, glial transporters as potential candidates in stroke intervention are becoming promising targets to enhance an effective and additional therapy for brain ischemia. In this review, we will describe in detail the role played by ionic transporters in influencing astrocyte, microglia, and oligodendrocyte activity and the implications that these transporters have in the progression of ischemic lesion.
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Bui BV, He Z, Vingrys AJ, Nguyen CTO, Wong VHY, Fortune B. Using the electroretinogram to understand how intraocular pressure elevation affects the rat retina. J Ophthalmol 2013; 2013:262467. [PMID: 23431417 PMCID: PMC3570935 DOI: 10.1155/2013/262467] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Accepted: 10/24/2012] [Indexed: 11/17/2022] Open
Abstract
Intraocular pressure (IOP) elevation is a key risk factor for glaucoma. Our understanding of the effect that IOP elevation has on the eye has been greatly enhanced by the application of the electroretinogram (ERG). In this paper, we describe how the ERG in the rodent eye is affected by changes in IOP magnitude, duration, and number of spikes. We consider how the variables of blood pressure and age can modify the effect of IOP elevation on the ERG. Finally, we contrast the effects that acute and chronic IOP elevation can have on the rodent ERG.
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Affiliation(s)
- Bang V. Bui
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC 3010, Australia
| | - Zheng He
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC 3010, Australia
| | - Algis J. Vingrys
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC 3010, Australia
| | - Christine T. O. Nguyen
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC 3010, Australia
| | - Vickie H. Y. Wong
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC 3010, Australia
| | - Brad Fortune
- Devers Eye Institute and Legacy Research Institute, Legacy Health, Portland, OR 97232, USA
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Drury PP, Bennet L, Booth LC, Davidson JO, Wassink G, Gunn AJ. Maturation of the mitochondrial redox response to profound asphyxia in fetal sheep. PLoS One 2012; 7:e39273. [PMID: 22720088 PMCID: PMC3376132 DOI: 10.1371/journal.pone.0039273] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Accepted: 05/22/2012] [Indexed: 12/04/2022] Open
Abstract
Fetal susceptibility to hypoxic brain injury increases over the last third of gestation. This study examined the hypothesis that this is associated with impaired mitochondrial adaptation, as measured by more rapid oxidation of cytochrome oxidase (CytOx) during profound asphyxia. Methods: Chronically instrumented fetal sheep at 0.6, 0.7, and 0.85 gestation were subjected to either 30 min (0.6 gestational age (ga), n = 6), 25 min (0.7 ga, n = 27) or 15 min (0.85 ga, n = 17) of complete umbilical cord occlusion. Fetal EEG, cerebral impedance (to measure brain swelling) and near-infrared spectroscopy-derived intra-cerebral oxygenation (ΔHb = HbO2 – Hb), total hemoglobin (THb) and CytOx redox state were monitored continuously. Occlusion was associated with profound, rapid fall in ΔHb in all groups to a plateau from 6 min, greatest at 0.85 ga compared to 0.6 and 0.7 ga (p<0.05). THb initially increased at all ages, with the greatest rise at 0.85 ga (p<0.05), followed by a progressive fall from 7 min in all groups. CytOx initially increased in all groups with the greatest rise at 0.85 ga (p<0.05), followed by a further, delayed increase in preterm fetuses, but a striking fall in the 0.85 group after 6 min of occlusion. Cerebral impedance (a measure of cytotoxic edema) increased earlier and more rapidly with greater gestation. In conclusion, the more rapid rise in CytOx and cortical impedance during profound asphyxia with greater maturation is consistent with increasing dependence on oxidative metabolism leading to earlier onset of neural energy failure before the onset of systemic hypotension.
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Affiliation(s)
- Paul P. Drury
- Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Laura Bennet
- Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Lindsea C. Booth
- Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand
- Howard Florey Institute, University of Melbourne, Melbourne, Victoria, Australia
| | - Joanne O. Davidson
- Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Guido Wassink
- Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Alistair J. Gunn
- Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand
- Starship Children's Hospital, Auckland, New Zealand
- * E-mail:
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Ford AL, An H, Vo KD, Lin W, Lee JM. Defining the ischemic penumbra using hyperacute neuroimaging: deriving quantitative ischemic thresholds. Transl Stroke Res 2012; 3:198-204. [PMID: 24323775 DOI: 10.1007/s12975-012-0181-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 04/05/2012] [Accepted: 04/17/2012] [Indexed: 11/28/2022]
Abstract
Despite three decades of promise, a neuroimaging biomarker capable of delineating the ischemic penumbra is yet to be definitively demonstrated. Much progress has been made, especially with MR imaging. However, in order to rigorously define an imaging biomarker of the ischemic penumbra, carefully designed studies which can derive ischemic thresholds using quantitative imaging parameters may be required. Two thresholds are of interest: one which distinguishes the ischemic core from penumbra, and another which distinguishes the penumbra from benign oligemia. In this review, we discuss one possible approach to define these thresholds by following tissue fate in the presence or absence of early reperfusion.
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Affiliation(s)
- Andria L Ford
- Department of Neurology, Washington University, School of Medicine, 600 South Euclid Avenue, Campus Box 8111, Saint Louis, MO, 63110, USA
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Powers WJ. Perfusion-diffusion mismatch: does it identify who will benefit from reperfusion therapy? Transl Stroke Res 2012; 3:182-7. [PMID: 24323773 DOI: 10.1007/s12975-012-0160-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Accepted: 03/19/2012] [Indexed: 01/30/2023]
Abstract
A method to determine which patients would benefit from reperfusion therapies after 4.5 h would greatly add to our ability to reduce the disability caused by stroke. The goal of magnetic resonance perfusion-diffusion imaging in hyperacute ischemic stroke is to identify regions of the brain that will die if untreated and will live and regain function if quickly reperfused. The clinical value of perfusion-diffusion imaging in hyperacute ischemic stroke can be proven only by demonstrating empirically in a randomized controlled trial (RCT) that there is an improvement in patient outcome that depends on the use of the neuroimaging modality to guide therapy. To date, there have been only a few RCTs that have evaluated whether perfusion-diffusion imaging can identify a subgroup of patients with ischemic stroke more than 4.5 h from onset in whom the overall benefit from reperfusion therapy outweighs the risk. None have met the rigorous design requirements of the three-group study necessary to adequately test this hypothesis, and none have even met their own criteria for demonstrating a clinical benefit. While studies are not sufficient to conclusively disprove the hypothesis there are no RCT data to support it, and thus, the clinical value of MRI perfusion-diffusion imaging in this setting remains unproven. It is worthy of further investigation in rigorously designed RCTs. However, the risks of symptomatic intracerebral hemorrhage with reperfusion therapies in acute ischemic stroke are proven. Unless RCT data are forthcoming to demonstrate that MRI perfusion-diffusion mismatch improves clinical outcome, it should not be used to guide delayed reperfusion therapy.
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Affiliation(s)
- William J Powers
- Department of Neurology, School of Medicine, University of North Carolina at Chapel Hill, Box 7025, Room 2131, 170 Manning Drive, Chapel Hill, NC, 27599, USA,
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Saggu R, Morrison B, Lowe JP, Pringle AK. Interleukin-1beta does not affect the energy metabolism of rat organotypic hippocampal-slice cultures. Neurosci Lett 2011; 508:114-8. [PMID: 22215116 DOI: 10.1016/j.neulet.2011.12.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Revised: 12/16/2011] [Accepted: 12/19/2011] [Indexed: 11/28/2022]
Abstract
The aim of this study was to examine the effect of the archetypal pro-inflammatory cytokine, interleukin-1beta (IL-1β), on high-energy phosphate levels within an ex vivo rat organotypic hippocampal-slice culture (OHSC) preparation using phosphorus ((31)P) magnetic resonance spectroscopy (MRS). Intrastriatal microinjection of IL-1β induces a chronic reduction in the apparent diffusion coefficient (ADC) of tissue water, which may be indicative of metabolic failure as established by in vivo models of acute cerebral ischaemia. The OHSC preparation enables examination of the effects of IL-1β on brain parenchyma per se, independent of the potentially confounding effects encountered in vivo such as perfusion changes, blood-brain barrier (BBB) breakdown and leukocyte recruitment. (31)P MRS is a technique that can detect multiple high-energy phosphate metabolites within a sample non-invasively. Here, for the first time, we characterise the energy metabolism of OHSCs using (31)P MRS and demonstrate that IL-1β does not compromise high-energy phosphate metabolism. Thus, the chronic reduction in ADC observed in vivo is unlikely to be a consequence of metabolic failure.
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Affiliation(s)
- Raman Saggu
- Department of Biochemistry, South Parks Road, University of Oxford, South Parks Road, OX1 3QU, UK.
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Dunn DE, He DN, Yang P, Johansen M, Newman RA, Lo DC. In vitro and in vivo neuroprotective activity of the cardiac glycoside oleandrin from Nerium oleander in brain slice-based stroke models. J Neurochem 2011; 119:805-14. [PMID: 21950737 DOI: 10.1111/j.1471-4159.2011.07439.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The principal active constituent of the botanical drug candidate PBI-05204, a supercritical CO(2) extract of Nerium oleander, is the cardiac glycoside oleandrin. PBI-05204 shows potent anticancer activity and is currently in phase I clinical trial as a treatment for patients with solid tumors. We have previously shown that neriifolin, which is structurally related to oleandrin, provides robust neuroprotection in brain slice and whole animal models of ischemic injury. However, neriifolin itself is not a suitable drug development candidate and the FDA-approved cardiac glycoside digoxin does not cross the blood-brain barrier. We report here that both oleandrin as well as the full PBI-05204 extract can also provide significant neuroprotection to neural tissues damaged by oxygen and glucose deprivation as occurs in ischemic stroke. Critically, we show that the neuroprotective activity of PBI-05204 is maintained for several hours of delay of administration after oxygen and glucose deprivation treatment. We provide evidence that the neuroprotective activity of PBI-05204 is mediated through oleandrin and/or other cardiac glycoside constituents, but that additional, non-cardiac glycoside components of PBI-05204 may also contribute to the observed neuroprotective activity. Finally, we show directly that both oleandrin and the protective activity of PBI-05204 are blood brain barrier penetrant in a novel model for in vivo neuroprotection. Together, these findings suggest clinical potential for PBI-05204 in the treatment of ischemic stroke and prevention of associated neuronal death.
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Affiliation(s)
- Denise E Dunn
- Center for Drug Discovery and Department of Neurobiology, Duke University Medical Center, Durham, North Carolina 27514, USA
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Frasch MG, Keen AE, Gagnon R, Ross MG, Richardson BS. Monitoring fetal electrocortical activity during labour for predicting worsening acidemia: a prospective study in the ovine fetus near term. PLoS One 2011; 6:e22100. [PMID: 21789218 PMCID: PMC3137606 DOI: 10.1371/journal.pone.0022100] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Accepted: 06/16/2011] [Indexed: 11/19/2022] Open
Abstract
Background Severe fetal acidemia during labour with arterial pH below 7.00 is associated with increased risk of hypoxic-ischemic brain injury. Electronic fetal heart rate (FHR) monitoring, the mainstay of intrapartum surveillance, has poor specificity for detecting fetal acidemia. We studied brain electrical activity measured with electrocorticogram (ECOG) in the near term ovine fetus subjected to repetitive umbilical cord occlusions (UCO) inducing FHR decelerations, as might be seen in human labour, to delineate the time-course for ECOG changes with worsening acidemia and thereby assess the potential clinical utility of fetal ECOG. Methodology/Principal Findings Ten chronically catheterized fetal sheep were studied through a series of mild, moderate and severe UCO until the arterial pH was below 7.00. At a pH of 7.24±0.04, 52±13 min prior to the pH dropping <7.00, spectral edge frequency (SEF) increased to 23±2 Hz from 3±1 Hz during each FHR deceleration (p<0.001) and was correlated to decreases in FHR and in fetal arterial blood pressure during each FHR deceleration (p<0.001). Conclusions/Significance The UCO-related changes in ECOG occurred in advance of the pH decreasing below 7.00. These ECOG changes may be a protective mechanism suppressing non-essential energy needs when oxygen supply to the fetal brain is decreased acutely. By detecting such “adaptive brain shutdown,” the need for delivery in high risk pregnant patients may be more accurately predicted than with FHR monitoring alone. Therefore, monitoring fetal electroencephalogram (EEG, the human equivalent of ECOG) during human labour may be a useful adjunct to FHR monitoring.
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Affiliation(s)
- Martin G Frasch
- Department of Obstetrics and Gynecology, Lawson Health Research Institute, The University of Western Ontario, London, Ontario, Canada.
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Active ingredients in Chinese medicines promoting blood circulation as Na+/K+ -ATPase inhibitors. Acta Pharmacol Sin 2011; 32:141-51. [PMID: 21293466 DOI: 10.1038/aps.2010.197] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The positive inotropic effect of cardiac glycosides lies in their reversible inhibition on the membrane-bound Na(+)/K(+)-ATPase in human myocardium. Steroid-like compounds containing a core structure similar to cardiac glycosides are found in many Chinese medicines conventionally used for promoting blood circulation. Some of them are demonstrated to be Na(+)/K(+)-ATPase inhibitors and thus putatively responsible for their therapeutic effects via the same molecular mechanism as cardiac glycosides. On the other hand, magnesium lithospermate B of danshen is also proposed to exert its cardiac therapeutic effect by effectively inhibiting Na(+)/K(+)-ATPase. Theoretical modeling suggests that the number of hydrogen bonds and the strength of hydrophobic interaction between the effective ingredients of various medicines and residues around the binding pocket of Na(+)/K(+)-ATPase are crucial for the inhibitory potency of these active ingredients. Ginsenosides, the active ingredients in ginseng and sanqi, substantially inhibit Na(+)/K(+)-ATPase when sugar moieties are attached only to the C-3 position of their steroid-like structure, equivalent to the sugar position in cardiac glycosides. Their inhibitory potency is abolished, however, when sugar moieties are linked to C-6 or C-20 position of the steroid nucleus; presumably, these sugar attachments lead to steric hindrance for the entrance of ginsenosides into the binding pocket of Na(+)/K(+)-ATPase. Neuroprotective effects of cardiac glycosides, several steroid-like compounds, and magnesium lithospermate B against ischemic stroke have been accordingly observed in a cortical brain slice-based assay model, and cumulative data support that effective inhibitors of Na(+)/K(+)-ATPase in the brain could be potential drugs for the treatment of ischemic stroke.
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