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Hertz L, Yager JY, Juurlink BH. Astrocyte survival in the absence of exogenous substrate: comparison of immature and mature cells. Int J Dev Neurosci 1995; 13:523-7. [PMID: 8553886 DOI: 10.1016/0736-5748(95)00049-m] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Astrocyte cultures prepared from newborn mouse neopallium were grown for either one or three weeks (representing, respectively, immature and mature astrocytes) and then exposed to deprivation of substrate (glucose and amino acids) for up to 48 hr. Cultures which had been deprived of metabolic substrates for either 24, 30, 36 or 48 hr were examined for lactate dehydrogenase efflux into the medium (an indicator of cell death) and ATP content. Significant cell death in mature astrocytes began after 30 hr of incubation in the substrate-deprived medium, a time when ATP had fallen to approximately 10% of its initial value. Immature astrocytes survived on a substrate-free medium for 48 hr before there was any indication at all of cell death, and this corresponded to a time when ATP values had fallen to 5% of the initial values. These findings are compared to previous observations during simulated ischemia (substrate deprivation plus anoxia) when (1) there was a faster cell death and (2) cell death occurred at higher ATP levels.
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Comparative Study |
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Abstract
Severe hypernatremia has been associated with a wide variety of central nervous system lesions. Neurologic sequelae are the usual outcome in those cases in which a lesion has been documented neuroradiologically. The authors report a 7-month-old male with severe hypernatremia who developed obtundation after correction of the electrolyte imbalance. Magnetic resonance imaging revealed bilateral thalamic signal changes that resolved on follow-up study, in accordance with complete clinical recovery. To the authors' knowledge, bilateral thalamic signal changes are previously unreported findings associated with hypernatremia. Pertinent literature and the clinical course of the authors' patient are the basis for questioning currently recommended guidelines for the rate of correction of hypernatremia.
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Case Reports |
26 |
18 |
53
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Yager JY, Asselin J. The effect of pre hypoxic-ischemic (HI) hypo and hyperthermia on brain damage in the immature rat. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 1999; 117:139-43. [PMID: 10567731 DOI: 10.1016/s0301-7516(99)00040-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
To determine the effect of pre-hypoxic-ischemic (HI) hypo and hyperthermia on neuropathologic outcome in the immature brain, groups of 7-day rat pups underwent unilateral common carotid artery ligation and exposure to hypoxia in 8% oxygen at 37 degrees C for 3 h. Prior to HI, rat pups were divided into three groups and received either: (a) 3-1 h periods, at 8-h intervals, 24 h prior to HI, (b) 1-3 h period, 24 h prior to HI, or (c) 1-3 h period, immediately prior to HI, of exposure to environmental temperatures of 28 degrees C, 31 degrees C, 34 degrees C, 37 degrees C, or 39 degrees C. Following HI, all animals were returned to their dams for neuropathologic assessment at 30 days of age. Mortality was highest among those animals exposed to pre-HI hypothermia at 28 degrees C. Only those animals who were pre-conditioned with hyperthermia at either 37 degrees C or 39 degrees C, immediately prior to HI, displayed a significant reduction in brain damage compared to control (p<0.01). These results indicate that hyperthermia induced prior to HI protects the immature brain from damage. This study further emphasizes the importance of a cautionary approach in implementing systemic hypothermia during clinical trials, and the need to further understand the timing and effects of thermoregulation on the immature brain.
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26 |
17 |
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Lowe DW, Hollis BW, Wagner CL, Bass T, Kaufman DA, Horgan MJ, Givelichian LM, Sankaran K, Yager JY, Katikaneni LD, Wiest D, Jenkins D. Vitamin D insufficiency in neonatal hypoxic-ischemic encephalopathy. Pediatr Res 2017; 82:55-62. [PMID: 28099429 PMCID: PMC5509506 DOI: 10.1038/pr.2017.13] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 12/26/2016] [Indexed: 12/14/2022]
Abstract
BACKGROUND Vitamin D has neuroprotective and immunomodulatory properties, and deficiency is associated with worse stroke outcomes. Little is known about effects of hypoxia-ischemia or hypothermia treatment on vitamin D status in neonates with hypoxic-ischemic encephalopathy (HIE). We hypothesized vitamin D metabolism would be dysregulated in neonatal HIE altering specific cytokines involved in Th17 activation, which might be mitigated by hypothermia. METHODS We analyzed short-term relationships between 25(OH) and 1,25(OH)2 vitamin D, vitamin D binding protein, and cytokines related to Th17 function in serum samples from a multicenter randomized controlled trial of hypothermia 33 °C for 48 h after HIE birth vs. normothermia in 50 infants with moderate to severe HIE. RESULTS Insufficiency of 25(OH) vitamin D was observed after birth in 70% of infants, with further decline over the first 72 h, regardless of treatment. 25(OH) vitamin D positively correlated with anti-inflammatory cytokine IL-17E in all HIE infants. However, Th17 cytokine suppressor IL-27 was significantly increased by hypothermia, negating the IL-27 correlation with vitamin D observed in normothermic HIE infants. CONCLUSION Serum 25(OH) vitamin D insufficiency is present in the majority of term HIE neonates and is related to lower circulating anti-inflammatory IL-17E. Hypothermia does not mitigate vitamin D deficiency in HIE.
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research-article |
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Yager JY, Armstrong EA, Black AM. Treatment of the term newborn with brain injury: simplicity as the mother of invention. Pediatr Neurol 2009; 40:237-43. [PMID: 19218037 DOI: 10.1016/j.pediatrneurol.2008.12.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2008] [Accepted: 11/03/2008] [Indexed: 11/28/2022]
Abstract
Neonatal brain injury remains a common cause of developmental disability, despite tremendously enhanced obstetrical and neonatal care. The timing of brain injury occurs throughout gestation, labor, and delivery, providing an evolving form of brain injury and a moving target for therapeutic intervention. Nonetheless, markedly improved methods are available to identify those infants injured at birth, via clinical presentation with neonatal encephalopathy and neuroimaging techniques. Postischemic hypothermia has been shown to be of tremendous clinical promise in several completed and ongoing trials. As part of this approach to the treatment of the newborn, other parameters of physiologic homeostasis can and should be attended to, with strong animal and clinical evidence that their correction will have dramatic influence on the outcome of the newborn infant. This review addresses aspects of newborn care to which we can direct our attention currently, and which should result in a safe and efficacious improvement in the prognosis of the newborn with neonatal encephalopathy.
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Review |
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15 |
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Yager JY, Brucklacher RM, Vannucci RC. Cerebral oxidative metabolism and redox state during hypoxia-ischemia and early recovery in immature rats. THE AMERICAN JOURNAL OF PHYSIOLOGY 1991; 261:H1102-8. [PMID: 1928392 DOI: 10.1152/ajpheart.1991.261.4.h1102] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Intracellular pH (pHi) and cytoplasmic and mitochondrial oxidation-reduction (redox) states of cerebral tissue were examined in relation to perturbations of glycolytic and tricarboxylic acid cycle intermediates and of high-energy phosphate reserves during hypoxia-ischemia and the early recovery period in the immature rat. Seven-day postnatal rats underwent unilateral common carotid artery ligation and exposure to 8% O2 for 3 h, after which they were quick frozen in liquid N2 at the terminus of hypoxia-ischemia and at 10, 30, 60, and 240 min of recovery for enzymatic fluorometric analysis of cerebral metabolites. During hypoxia-ischemia, concentrations of glucose and alpha-ketoglutarate in the cerebral hemisphere ipsilateral to the carotid artery occlusion were depleted to 10 and 70% of control, respectively; pyruvate was unchanged. During recovery, glucose, pyruvate, and alpha-ketoglutarate increased above their respective control values. Calculated pHi decreased from 7.0 (control) to 6.6 during hypoxia-ischemia and normalized by 10 min of recovery. The cytoplasmic NAD+/NADH ratio decreased (increased reduction) to 50% of control during hypoxia-ischemia and remained in the reduced state throughout 4 h of recovery. Paradoxically, mitochondrial NAD+/NADH was oxidized at the terminus of hypoxia-ischemia. The mitochondrial oxidation which developed during hypoxia-ischemia presumably results from a limitation of cellular substrate (glucose) supply, which in turn leads to a depletion of high-energy phosphate reserves, culminating in brain damage.
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Vexler ZS, Sharp FR, Feuerstein GZ, Ashwal S, Thoresen M, Yager JY, Ferriero DM. Translational stroke research in the developing brain. Pediatr Neurol 2006; 34:459-63. [PMID: 16765824 DOI: 10.1016/j.pediatrneurol.2005.10.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2005] [Revised: 08/15/2005] [Accepted: 10/06/2005] [Indexed: 11/26/2022]
Abstract
Preclinical animal models can help guide the development of clinical pediatric and newborn stroke trials. Data obtained using currently available models of hypoxia-ischemia and focal stroke have demonstrated the need for age-appropriate models. There are age-related differences in susceptibility of the immature brain to oxidative stress and inflammation, as well as in the rate and degree of apoptotic neuronal death. These issues need to be carefully addressed in designing future clinical trials.
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Ghotra SK, Johnson JA, Qiu W, Newton AS, Rasmussen C, Yager JY. Health-related quality of life and its determinants in paediatric arterial ischaemic stroke survivors. Arch Dis Child 2018. [PMID: 29519944 DOI: 10.1136/archdischild-2017-313334] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
OBJECTIVE Health-related quality of life (HRQL) instruments are patient or proxy-reported outcome measures that provide a comprehensive and subjective assessment of patient's well-being and hence vital for health outcomes evaluation. A clear and thorough understanding of HRQL and its determinants is especially important to appropriately guide health-improving interventions. In this study, HRQL of paediatric arterial ischaemic stroke survivors was assessed using guidelines recommended for interpretation and reporting of the patient-reported outcome data. Determinants of HRQL were also explored. METHODS Children diagnosed with arterial ischaemic stroke between 2003 and 2012 were assessed at least 1 year poststroke using the parent-proxy report versions of the Pediatric Quality of Life Inventory 4.0 and Pediatric Stroke Recurrence and Recovery Questionnaire. HRQL data were compared with population norms and used as outcome in multiple linear regression analysis. RESULTS 59 children were evaluated. Mean age at diagnosis of stroke was 2.2 years. Mean age at assessment and time elapsed since stroke was 7 years and 5 years, respectively. A total of 41% children had normal global outcome, whereas 51% had moderate to severe deficits. A lower overall HRQL was observed in both self and proxy reports. Parents reported the maximum impairment in emotional domain, whereas children indicated physical functioning to be the most affected. Neurological outcome, site of stroke and socioeconomic status were independently associated with overall HRQL. CONCLUSIONS Lower HRQL was demonstrated in children who survived arterial ischaemic stroke. Socioeconomic status of families was an important determinant of HRQL, over and above clinical parameters.
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Jack AS, Chow MM, Fiorillo L, Chibuk T, Yager JY, Mehta V. Bilateral pial synangiosis in a child with PHACE syndrome. J Neurosurg Pediatr 2016; 17:70-5. [PMID: 26405843 DOI: 10.3171/2015.5.peds1578] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The acronym PHACE has been used to denote a constellation of abnormalities: posterior fossa anomalies, facial hemangiomas, arterial anomalies, cardiac anomalies, and eye abnormalities. Approximately 30% of patients with large facial hemangiomas have PHACE syndrome, with the vast majority having intracranial arteriopathy. Few reports characterize neurological deterioration from this intracranial arteriopathy, and even fewer report successful treatment thereof. The authors report on a case of a child with PHACE syndrome who presented with an ischemic stroke from a progressive intracranial arteriopathy and describe her successful treatment with bilateral pial synangiosis. An 8-month old girl diagnosed with PHACE syndrome was found to have bilateral internal carotid artery stenosis. Although initially asymptomatic, a few months after diagnosis she suffered a right frontal and parietal stroke. MRI and cerebral angiography investigations demonstrated progressive intracranial arterial stenosis and occlusion. The patient then underwent indirect cerebral revascularization surgery. At 2-year follow-up, she exhibited clinical improvement with persistent speech and motor developmental delay. Follow-up MRI and cerebral angiography showed no new ischemic events and robust extensive vascular collateralization from surgery. PHACE syndrome is an uncommon disease, and affected patients often have cerebral arteriopathy. Although the underlying natural history of cerebral arteriopathy in PHACE remains unclear, cerebral revascularization may represent a potential therapy for symptomatic patients.
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Case Reports |
9 |
12 |
60
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Goez HR, Jacob FD, Fealey RD, Patterson MC, Ramaswamy V, Persad R, Johnson ES, Yager JY. An unusual presentation of copper metabolism disorder and a possible connection with Niemann-Pick type C. J Child Neurol 2011; 26:518-21. [PMID: 21273508 DOI: 10.1177/0883073810383983] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abnormal copper metabolism has been linked with neurological disorders, such as Wilson and Menkes disease. Another disorder causing symptoms similar to copper metabolism disorder is Niemann-Pick type C. However, a definite pathophysiological connection between Niemann-Pick type C and copper metabolism disorders has never been established. The authors present an adolescent with an unusual presentation of copper deficiency-dysarthria, ataxia, and vertical gaze paresis, without significant cognitive degeneration or pathological magnetic resonance imaging (MRI). The patient was found to carry 2 mutations in the NPC1 gene. A possible link, explaining how copper deficiency might induce the Niemann-Pick phenotype might involve overproduction of cholesterol and inhibition of acid sphingomyelinase. We suggest that copper metabolism disorders be included in the differential diagnosis for ataxia and dysarthria, even in cases with unusual presentations. Moreover, should the connection between copper and Niemann-Pick be validated, screening for copper metabolism disorders may be advisable in Niemann-Pick type C patients and vice-versa.
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Case Reports |
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11 |
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Srivastava R, Shaw OEF, Armstrong E, Morneau-Jacob FD, Yager JY. Patterns of Brain Injury in Perinatal Arterial Ischemic Stroke and the Development of Infantile Spasms. J Child Neurol 2021; 36:583-588. [PMID: 33543672 DOI: 10.1177/0883073820986056] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
INTRODUCTION Perinatal arterial ischemic stroke (PAIS) underlies approximately 10% of infantile spasms (IS). We aim to identify patterns of brain injury in ischemic stroke that may predispose infants to infantile spasms. METHODS Sixty-four perinatal arterial ischemic stroke patients were identified meeting the following inclusion criteria: term birth, magnetic resonance imaging (MRI) showing ischemic stroke or encephalomalacia in an arterial distribution, and follow-up records. Patients who developed infantile spasms (PAIS-IS) were analyzed descriptively for ischemic stroke injury patterns and were compared to a seizure-free control group (PAIS-only). Stroke injury was scored using the modified pediatric ASPECTS (modASPECTS). RESULTS The PAIS-IS (n = 9) group had significantly higher modASPECTS than the PAIS-only (n = 16) group (P = .002, Mann-Whitney). A greater proportion of PAIS-IS patients had injury to deep cerebral structures (67%) than PAIS-only (25%). CONCLUSION Infarct size was significantly associated with infantile spasms development. Results support theories implicating deep cerebral structures in infantile spasms pathogenesis. This may help identify perinatal arterial ischemic stroke patients at risk of infantile spasms, facilitating more timely diagnosis.
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Observational Study |
4 |
10 |
62
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Abstract
Mycoplasma pneumoniae encephalitis is a recognized cause of reversible coma in children. As an etiology of infectious encephalitis, it yields a relatively poorer prognosis than most other causes of infectious encephalopathies. Encephalitis is generally diagnosed by a constellation of clinical symptoms and confirmed by a cerebrospinal fluid (CSF) examination revealing cell pleocytosis and elevated protein. That Mycoplasma pneumoniae encephalopathy can occur in the presence of a normal CSF examination is less well appreciated. The authors report two children who presented with coma and normal CSF findings in whom a diagnosis of acute Mycoplasma pneumoniae infection was made. The two children both had rapid and complete recovery over several days. These cases exemplify that coma can result from acute infection with Mycoplasma pneumoniae in the absence of an inflammatory CSF response and that a normal CSF may herald a more favorable prognosis.
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Case Reports |
26 |
10 |
63
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Nguyen AT, Bahry AMA, Shen KQ, Armstrong EA, Yager JY. Consumption of broccoli sprouts during late gestation and lactation confers protection against developmental delay induced by maternal inflammation. Behav Brain Res 2016; 307:239-49. [PMID: 27038765 DOI: 10.1016/j.bbr.2016.03.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 03/04/2016] [Accepted: 03/06/2016] [Indexed: 11/27/2022]
Abstract
BACKGROUND The presence of a fetal inflammatory response is linked to cerebral palsy. Unfortunately no preventive therapies are available. In this study, we determined whether dietary supplementation with broccoli sprouts (BrSp), a phase-II enzyme inducer, would be effective in preventing the behavioural and pathologic manifestations in a rodent model of inflammation during late pregnancy. METHODS Pregnant Long-Evans rats were administered i.p. Injections of saline (100μl) or lipopolysaccharide (LPS, 200μg/kg), every 12h on embryonic day (E) 19 and 20. In the treatment groups, dams were supplemented with 200mg/day of dried BrSp from E14 until postnatal day 21. Pups underwent a series of neurodevelopmental reflex tests from postnatal day 3-21 followed by neuropathological analyses. RESULTS Pups born from the LPS group were significantly growth restricted (p<0.001) and delayed in hindlimb placing (p<0.05), cliff avoidance (p<0.05), and gait (p<0.001) compared to controls. In the open field behaviour analyses, LPS pups had an increase in grooming behaviour (p<0.05) and a decreased amount of time spent in the center of the box compared to controls. Dietary supplementation with BrSp to offspring exposed to LPS had increased birth weights (p<0.001), were no longer delayed in acquiring hindlimb placing, cliff avoidance, gait, and posture, and groomed less compared to LPS alone pups (p<0.01). Histological analyses revealed that LPS pups had reduced myelin basic protein compared to controls. CONCLUSIONS Our data suggest that BrSp dietary supplementation during pregnancy may be effective in preventing growth restriction and neurodevelopmental delays.
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Research Support, Non-U.S. Gov't |
9 |
8 |
64
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Bell E, Rasmussen LA, Mazer B, Shevell M, Miller SP, Synnes A, Yager JY, Majnemer A, Muhajarine N, Chouinard I, Racine E. Magnetic resonance imaging (MRI) and prognostication in neonatal hypoxic-ischemic injury: a vignette-based study of Canadian specialty physicians. J Child Neurol 2015; 30:174-81. [PMID: 24789518 DOI: 10.1177/0883073814531821] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Magnetic resonance imaging (MRI) could improve prognostication in neonatal brain injury; however, factors beyond technical or scientific refinement may impact its use and interpretation. We surveyed Canadian neonatologists and pediatric neurologists using general and vignette-based questions about the use of MRI for prognostication in neonates with hypoxic-ischemic injury. There was inter- and intra-vignette variability in prognosis and in ratings about the usefulness of MRI. Severity of predicted outcome correlated with certainty about the outcome. A majority of physicians endorsed using MRI results in discussing prognosis with families, and most suggested that MRI results contribute to end-of-life decisions. Participating neonatologists, when compared to participating pediatric neurologists, had significantly less confidence in the interpretation of MRI by colleagues in neurology and radiology. Further investigation is needed to understand the complexity of MRI and of its application. Potential gaps relative to our understanding of the ethical importance of these findings should be addressed.
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Lu L, Armstrong EA, Yager JY, Unsworth LD. Sustained Release of Dexamethasone from Sulfobutyl Ether β-cyclodextrin Modified Self-Assembling Peptide Nanoscaffolds in a Perinatal Rat Model of Hypoxia-Ischemia. Adv Healthc Mater 2019; 8:e1900083. [PMID: 30977596 DOI: 10.1002/adhm.201900083] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 03/13/2019] [Indexed: 11/10/2022]
Abstract
Inflammation plays a critical role in the development of hypoxia-ischemia (HI) induced newborn brain damage. A localized, sustained delivery of dexamethasone (Dex) through an intracerebral injection could reduce the inflammatory response in the injured perinatal brain while avoiding unnecessary side effects. Herein, investigated using anionic sulfobutyl ether β-cyclodextrin (SBE-β-CD) to load Dex in the (RADA)4 nanofiber networks as a means of reducing the inflammatory response to HI injury is investigated. The ionic interaction between SBE-β-CD and (RADA)4 dramatically affects nanofiber formation and the stability of the nanoscaffold is highly dependent on the SBE-β-CD/(RADA)4 ratio. It is observed that the Dex release rate is affected by the concentration of SBE-β-CD and (RADA)4 peptide. A higher concentration of SBE-β-CD or (RADA)4 results in a higher drug encapsulation efficiency and slower release rate of Dex. This phenomenon may be related to the structure of fiber bundles. Animal studies show that nanoscaffold loaded with Dex inhibits both microglia activation and glial scar formation compared to controls (Dex alone or nanoscaffold alone) within 2 days of injury. It is thought that this is a step toward building a multifaceted nanoscaffold that can be used to treat HI events in perinates.
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Research Support, Non-U.S. Gov't |
6 |
7 |
66
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Yager JY, Christensen MA, Vannucci RC. Regional cerebral blood flow following hypothermic circulatory arrest in newborn dogs. Brain Res 1993; 620:122-6. [PMID: 8402184 DOI: 10.1016/0006-8993(93)90277-t] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A model of hypothermic circulatory arrest has been developed in newborn dogs which simulates the procedure used for the operative repair of congenital cardiac defects in human infants. Hypothermic circulatory arrest for 1.0 h causes no brain damage, whereas cardiac arrest for 1.75 h results in damage of the cerebral cortex, basal ganglia and to a lesser extent the claustrum and amygdaloid nucleus. In the present study, we determined regional cerebral blood flow (rCBF) during 24 h of recovery from hypothermic circulatory arrest. Newborn nitrous oxide anesthetized and artificially ventilated dogs were cooled to 20 degrees C and subjected to cardiac arrest by the i.v. injection of KCl for either 1.0 or 1.75 h. Thereafter, animals were resuscitated, rewarmed to 37 degrees C, and rCBF measured with [14C]iodoantipyrine at either 2 or 18 h of recovery. Control animals were rendered hypothermic to 20 degrees C without cardiac arrest for 1.0 or 1.75 h prior to rewarming. No alterations in CBF at either 2 or 18 h of recovery were present in any of 16 analyzed structures in animals previously subjected to hypothermic circulatory arrest compared to controls rendered hypothermic alone. A direct linear correlation existed between mean arterial blood pressure and blood flow within frontal, parietal and occipital cortex, occipital white matter, hypothalamus and cerebellar vermis in puppies arrested for 1.75 h and recovered for 2 h, suggesting a loss of CBF autoregulation at this interval. No such association between blood pressure and CBF was apparent at 18 h of recovery.(ABSTRACT TRUNCATED AT 250 WORDS)
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Abstract
Inter-observer agreement was evaluated for twelve items used in the neurological assessment of comatose children. Data were obtained prospectively on fifteen patients examined independently by two observers in a double-blind fashion. Observer variability was measured by using the Disagreement Rate and Kappa statistic. The Disagreement Rate ranged from 0.01 to 0.12 for all items. Values for Kappa statistic were generally in accordance with those for Disagreement Rate. The data suggest fair to almost perfect inter-observer agreement for the items used to assess comatose children in this study.
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Yager JY, Brucklacher RM, Mujsce DJ, Vannucci RC. Cerebral oxidative metabolism during hypothermia and circulatory arrest in newborn dogs. Pediatr Res 1992; 32:547-52. [PMID: 1480456 DOI: 10.1203/00006450-199211000-00012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
To ascertain the alterations in cerebral oxidative and energy metabolism that occur during hypothermic circulatory arrest, nitrous oxide-anesthetized, paralyzed, and artificially ventilated newborn dogs were surface cooled to 18-20 degrees C, after which their hearts were arrested with KCl. At 10, 30, 60, and 105 min of circulatory arrest, their brains were prepared by in situ freezing for the regional analysis of glycolytic intermediates and high-energy phosphate reserves. Hypothermia alone was associated with optimal preservation of labile metabolites in brain, even in caudal brainstem and cerebellum, compared with barbiturate-anesthetized littermates. After onset of hypothermic circulatory arrest, glucose decreased progressively in cerebral cortex, caudate nucleus, hippocampus, and subcortical white matter to negligible levels by 30 min. Pyruvate increased transiently (+50%) at 10 min, whereas lactate increased and plateaued (10-11 mmol/kg) at 30 min. The disproportionate increases in pyruvate and lactate resulted in a progressive rise in the lactate/pyruvate ratio. Phosphocreatine fell precipitously to < 0.5 mmol/kg in all structures, with a preservation of ATP for the first 10 min of cerebral ischemia. Thereafter, ATP decreased to < 0.1 mmol/kg in cerebral cortex and between 0.1 and 0.2 mmol/kg in caudate nucleus, hippocampus, and white matter. Total adenine nucleotides (ATP+ADP+AMP) were partially depleted by 30 min in the gray matter structures but were unchanged from control for 60 min in white matter. The findings showed a direct correlation between preservation of cerebral energy stores during hypothermic circulatory arrest and the selective resistance of subcortical white matter to ischemic damage.(ABSTRACT TRUNCATED AT 250 WORDS)
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Yager JY, Johnston B, Seshia SS. Coma scales in pediatric practice. AMERICAN JOURNAL OF DISEASES OF CHILDREN (1960) 1990; 144:1088-91. [PMID: 2403089 DOI: 10.1001/archpedi.1990.02150340032019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Interobserver variability for six coma scales was assessed prospectively on a sample of 15 comatose children, by two physicians, in a double-blind fashion. The six scales were the Glasgow Coma Scale, the Simpson and Reilly Scale, the Children's Coma Score, the Children's Orthopedic Hospital and Medical Center Scale, the Jacobi Scale, and the 0 to IV Scale. Interobserver variability was measured by using disagreement rate and the kappa statistic. The results from both methods were generally concordant. The disagreement rate for the various items in the different scales ranged from a high of 0.20 to a low of 0.03. The disagreement rate was greater than 0.10 for verbal responses in the Children's Coma Score and Glasgow Coma Scale and for both items in the Children's Orthopedic Hospital and Medical Center Scale. The disagreement rate was 0.10 or less for the 0 to IV Scale and for all items in the Simpson and Reilly and Jacobi scales. The relatively high interobserver agreement for these scales makes them more suitable for the pediatric setting than the other three scales, since good agreement is essential for interpreting data reliably, both in clinical practice and for research.
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Clinical Trial |
35 |
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70
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Mitchell RS, Yager JY, Marks SD. Childhood onset demyelination and Graves' disease: shared antigen or autoimmune clustering? J Pediatr Endocrinol Metab 2007; 20:1233-6. [PMID: 18183795 DOI: 10.1515/jpem.2007.20.11.1233] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
We describe a case of concomitant Graves' disease and demyelination, with optic neuritis and cerebellar dysfunction, in an adolescent girl. Autoimmune thyroid disease with encephalopathy is the hallmark of Hashimoto's encephalopathy, linking thyroid and central nervous system dysfunction. However, to our knowledge, Graves' disease has not been previously reported in association with clinically isolated demyelinating disease in childhood.
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Case Reports |
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4 |
71
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Yager JY, Seshia SS. Sublingual lorazepam in childhood serial seizures. AMERICAN JOURNAL OF DISEASES OF CHILDREN (1960) 1988; 142:931-2. [PMID: 3414622 DOI: 10.1001/archpedi.1988.02150090029016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Sublingual lorazepam was successful in controlling serial seizures in ten children. There was both intrasubject and intersubject variability in the effective dose, which ranged from about 0.05 mg/kg to 0.15 mg/kg. Side effects were minimal and consisted of drowsiness, unsteadiness, nausea, and hyperactivity. Sublingual lorazepam is an easy and effective way to treat serial seizures at home.
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Case Reports |
37 |
4 |
72
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Goez HR, Jacob FD, Yager JY. Lingual dyskinesia and tics: a novel presentation of copper-metabolism disorder. Pediatrics 2011; 127:e505-8. [PMID: 21199858 DOI: 10.1542/peds.2010-2391] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Copper is a trace element that is required for cellular respiration, neurotransmitter biosynthesis, pigment formation, antioxidant defense, peptide amidation, and formation of connective tissue. Abnormalities of copper metabolism have been linked with neurologic disorders that affect movement, such as Wilson disease and Menkes disease; however, the diagnosis of non-Wilson, non-Menkes-type copper-metabolism disorders has been more elusive, especially in cases with atypical characteristics. We present here the case of an adolescent with a novel presentation of copper-metabolism disorder who exhibited acute severe hemilingual dyskinesia and prominent tics, with ballismus of the upper limbs, but had normal brain and spinal MRI results and did not show any signs of dysarthria or dysphagia. His serum copper and ceruloplasmin levels were low, but his urinary copper level was elevated after penicillamine challenge. We conclude that copper-metabolism disorders should be included in the differential diagnosis for movement disorders, even in cases with highly unusual presentations, because many of them are treatable. Moreover, a connection between copper-metabolism disorders and tics is presented, to our knowledge, for the first time in humans; further investigation is needed to better establish this connection and understand its underlying pathophysiology.
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Case Reports |
14 |
3 |
73
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Ladak Z, Garcia E, Yoon J, Landry T, Armstrong EA, Yager JY, Persad S. Sulforaphane (SFA) protects neuronal cells from oxygen & glucose deprivation (OGD). PLoS One 2021; 16:e0248777. [PMID: 33735260 PMCID: PMC7971874 DOI: 10.1371/journal.pone.0248777] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 03/04/2021] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Perinatal brain injury results in neurodevelopmental disabilities (neuroDDs) that include cerebral palsy, autism, attention deficit disorder, epilepsy, learning disabilities and others. Commonly, injury occurs when placental circulation, that is responsible for transporting nutrients and oxygen to the fetus, is compromised. Placental insufficiency (PI) is a reduced supply of blood and oxygen to the fetus and results in a hypoxic-ischemic (HI) environment. A significant HI state in-utero leads to perinatal compromise, characterized by fetal growth restriction and brain injury. Given that over 80% of perinatal brain injuries that result in neuroDDs occur during gestation, prior to birth, preventive approaches are needed to reduce or eliminate the potential for injury and subsequent neuroDDs. Sulforaphane (SFA) derived from cruciferous vegetables such as broccoli sprouts (BrSps) is a phase-II enzyme inducer that acts via cytoplasmic Nrf2 to enhance the production of anti-oxidants in the brain through the glutathione pathway. We have previously shown a profound in vivo neuro-protective effect of BrSps/SFA as a dietary supplement in pregnant rat models of both PI and fetal inflammation. Strong evidence also points to a role for SFA as treatment for various cancers. Paradoxically, then SFA has the ability to enhance cell survival, and with conditions of cancer, enhance cell death. Given our findings of the benefit of SFA/Broccoli Sprouts as a dietary supplement during pregnancy, with improvement to the fetus, it is important to determine the beneficial and toxic dosing range of SFA. We therefore explored, in vitro, the dosing range of SFA for neuronal and glial protection and toxicity in normal and oxygen/glucose deprived (OGD) cell cultures. METHODS OGD simulates, in vitro, the condition experienced by the fetal brain due to PI. We developed a cell culture model of primary cortical neuronal, astrocyte and combined brain cell co-cultures from newborn rodent brains. The cultures were exposed to an OGD environment for various durations of time to determine the LD50 (duration of OGD required for 50% cell death). Using the LD50 as the time point, we evaluated the efficacy of varying doses of SFA for neuroprotective and neurotoxicity effects. Control cultures were exposed to normal media without OGD, and cytotoxicity of varying doses of SFA was also evaluated. Immunofluorescence (IF) and Western blot analysis of cell specific markers were used for culture characterization, and quantification of LD50. Efficacy and toxicity effect of SFA was assessed by IF/high content microscopy and by AlamarBlue viability assay, respectively. RESULTS We determined the LD50 to be 2 hours for neurons, 8 hours for astrocytes, and 10 hours for co-cultures. The protective effect of SFA was noticeable at 2.5 μM and 5 μM for neurons, although it was not significant. There was a significant protective effect of SFA at 2.5 μM (p<0.05) for astrocytes and co-cultures. Significant toxicity ranges were also confirmed in OGD cultures as ≥ 100 μM (p<0.05) for astrocytes, ≥ 50 μM (p<0.01) for co-cultures, but not toxic in neurons; and toxic in control cultures as ≥ 100 μM (p<0.01) for neurons, and ≥ 50 μM (p<0.01) for astrocytes and co-cultures. One Way ANOVA and Dunnett's Multiple Comparison Test were used for statistical analysis. CONCLUSIONS Our results indicate that cell death shows a trend to reduction in neuronal and astrocyte cultures, and is significantly reduced in co-cultures treated with low doses of SFA exposed to OGD. Doses of SFA that were 10 times higher were toxic, not only under conditions of OGD, but in normal control cultures as well. The findings suggest that: 1. SFA shows promise as a preventative agent for fetal ischemic brain injury, and 2. Because the fetus is a rapidly growing organism with profound cell multiplication, dosing parameters must be established to insure safety within efficacious ranges. This study will influence the development of innovative therapies for the prevention of childhood neuroDD.
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research-article |
4 |
2 |
74
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Rezvani M, Yager JY, Hartfield DS. Group A streptococcal meningitis as a complication of an infected capillary haemangioma. Eur J Pediatr 2004; 163:19-21. [PMID: 14610671 DOI: 10.1007/s00431-003-1334-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2003] [Accepted: 09/29/2003] [Indexed: 11/30/2022]
Abstract
UNLABELLED We report a case of group A streptococcal meningitis in an infant resulting from an infected capillary haemangioma. The child suffered significant morbidity including cerebral infarction, epilepsy, and developmental delay. Treatment of infected capillary haemangiomas remains controversial and inconsistent. CONCLUSION Our experience of this infant, resulting in profound neurological morbidity suggests that group A Streptococcus can be a virulent organism in the young child and that capillary haemangiomas must be treated aggressively at the first sign of infection.
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Case Reports |
21 |
2 |
75
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Rashid M, Goez HR, Caine V, Yager JY, Joyce AS, Newton AS. After a child's acquired brain injury (ABI): An ethnographic study of being a parent. J Pediatr Rehabil Med 2016; 9:303-313. [PMID: 27935570 DOI: 10.3233/prm-160403] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
PURPOSE To explore the meanings associated with being a parent of a child with an aquired brain injury (ABI). METHODS An ethnographic study was conducted with parents of children aged 3 to 10 years who had acquired a severe brain injury. Purposeful sampling was used to recruit parents from the Glenrose Rehabilitation Hospital in Edmonton, Alberta. Data collection involved participant observation, fieldwork and semi-structured interviews. Field notes and interviews transcriptions were analysed using a thematic analysis framework and informed by symbolic interactionism theory. RESULTS Six parent dyads (mothers and fathers) and 4 mothers participated in the study.Parents' meanings of `parenting' a child with severe brain injury were shaped by the injury, wide range of familial dynamics, and interactions. Six main themes related to parental meanings emerged from our data: (1) Getting `back to normal'; (2) Relying on a support system; (3) Worrying something bad may happen after the injury; (4) Going through a range of emotions following the injury; (5) Changing family dynamics after the injury; and (6) Ongoing performativity. CONCLUSION Parents' meanings of `parenting' a child are extensively impacted by their child's functioning after the ABI. Having a greater appreciation of these experiences may be beneficial for medical professionals.
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Observational Study |
9 |
2 |