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Mark S Scher - One of the best experts on this subject based on the ideXlab platform.
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physiologic brain Dysmaturity in late preterm infants
Pediatric Research, 2011Co-Authors: Mark S Scher, Mark W Johnson, Susan M Ludington, Kenneth A LoparoAbstract:Neonatal EEG sleep was used to determine whether differences are expressed between healthy late preterm and full-term (FT) groups. Twenty-seven 24-channel multihour studies were recorded at similar postmenstrual ages (PMA) and analyzed for eight asymptomatic late preterm infants (LPT) compared with 19 healthy FT infants as a preliminary analysis, followed by a comparison of a subset of eight FT infants, matched for gender, race, and PMA. Z scores were performed on data sets from each group pair comparing each of seven EEG/Sleep measures for entire recordings, active sleep (AS) and quiet sleep (QS) segments and artifact-free intervals. Six of seven measures showed differences between the eight LPT and eight matched FT cohort pair comparisons of >0.3; rapid eye movements, arousals during QS, spectral correlations between homologous centrotemporal regions during QS, spectral beta/alpha power ratios during AS and QS, a spectral measure of respiratory regularity during QS, and sleep cycle length. Quantitative neurophysiologic analyses define differences in brain maturation between LPT and FT infants at similar PMA. Altered EEG/Sleep behaviors in the LPT are biomarkers of developmental neuroplasticity involving interconnected neuronal networks adapting to conditions of prematurity for this largest segment of the preterm neonatal population.
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automated detection of neonate eeg sleep stages
Computer Methods and Programs in Biomedicine, 2009Co-Authors: Alexandra Piryatinska, Mark S Scher, Gyorgy Terdik, Wojbor A Woyczynski, Kenneth A Loparo, Anatoly ZlotnikAbstract:The paper integrates and adapts a range of advanced computational, mathematical and statistical tools for the purpose of analysis of neonate sleep stages based on extensive electroencephalogram (EEG) recordings. The level of brain Dysmaturity of a neonate is difficult to assess by direct physical or cognitive examination, but Dysmaturity is known to be directly related to the structure of neonatal sleep as reflected in the nonstationary time series produced by EEG signals which, importantly, can be collected trough a noninvasive procedure. In the past, the assessment of sleep EEG structure has often been done manually by experienced clinicians. The goal of this paper is to develop rigorous algorithmic tools for the same purpose by providing a formal scheme to separate different sleep stages corresponding to different stationary segments of the EEG signal based on statistical analysis of the spectral and nonlinear characteristics of the sleep EEG recordings. The methods developed in this paper can, potentially, be translated to other areas of biomedical research.
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neurophysiological assessment of brain function and maturation ii a measure of brain Dysmaturity in healthy preterm neonates
Pediatric Neurology, 1997Co-Authors: Mark S ScherAbstract:Severe brain disorders can be expressed as markedly abnormal encephalopathic EEG patterns in neonates who are usually neurologically depressed, with abnormal levels of reactivity and tone. This symptomatic group is now a minority of medically ill neonates as a result of more vigorous fetal and neonatal resuscitative efforts. Most neonates alternatively express brain dysfunction as more pervasive alterations in EEG-sleep organization or maturation, usually in the absence or after resolution of abnormal clinical signs. One form of dysfunction is expressed as neurophysiologic Dysmaturity. Brain Dysmaturity may reflect altered rates of development in infants who sustained prenatal or postnatal stresses, as discussed in the first part of this review. We now summarize our findings of dysmature EEG-sleep development at conceptional term ages in an asymptomatic preterm cohort during a prolonged extrauterine period before discharge from the nursery. Dysmaturity of EEG-sleep function was expressed as delayed and/or accelerated physiologic behaviors, as compared with behaviors expected for the conceptional age. Dysmature brain function at conceptional term ages was also associated with poorer neurodevelopmental performances at 12 and 24 months of age. Neuronal pathways which subserve state-specific neurophysiologic behaviors will functionally adapt to stress by either slowing or accelerating neurological maturation. Through ontogenetic brain adaptation, which continues during postnatal development, a balance is maintained between the needs of the present developmental stage and anticipated needs during subsequent stages of maturation. How medical complications and environmental influences interact to promote greater brain Dysmaturity in the neonate is still unknown. EEG sleep study can serve as a useful neurophysiologic screening procedure for the child suspected of having a subclinical presentation of an emerging static encephalopathy; longitudinal studies will then document deviations from expected ontogeny in the vulnerable child who is later stressed by environmental and socioeconomic factors.
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neurophysiological assessment of brain function and maturation i a measure of brain adaptation in high risk infants
Pediatric Neurology, 1997Co-Authors: Mark S ScherAbstract:Neurophysiologic assessments using EEG/polysomnographic studies permit the clinician to recognize expected patterns of brain maturation in the healthy neonate. By comparison, one can detect encephalopathic behaviors of newborns who are medically at risk. Severe physiologic expressions of encephalopathy are associated with neuropathologic lesions on postmortem examinations, brain lesions documented on neuroimaging studies, and major neurodevelopmental sequelae of survivors. However, such patterns are observed for only a minority of high risk neonates; less severe encephalopathies occur more frequently in neonates without evidence of brain lesions on imaging studies who either recover from medical illness or who manifest no findings of neurological dysfunction. These subtle and persistent brain disorders are obviously more difficult to detect and grade. This is specifically relevant for preterm infants in whom various degrees of encephalopathy may exist, but whose physiologic behaviors must be distinguished from expected behavioral and neurophysiologic patterns of prematurity. Neonates may express brain dysfunction as altered rates of brain maturation, as compared with expected patterns for a given conceptional age. Neurophysiologic expressions of brain Dysmaturity, either from prenatal and/or postnatal stresses, may actually occur in a substantially larger segment of the high risk neonatal population than has been anticipated. EEG-sleep studies can serve as a noninvasive neurophysiologic probe of brain organization and maturation to extend clinical observations to assess the severity and persistence of brain dysfunction in a neonate who may be at risk for later neurodevelopmental compromise.
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positive temporal sharp waves on eeg recordings of healthy neonates a benign pattern of Dysmaturity in pre term infants at post conceptional term ages
Electroencephalography and Clinical Neurophysiology, 1994Co-Authors: Mark S Scher, J M Bova, S G Dokianakis, Doris A SteppeAbstract:Abstract One complete sleep cycle was selected in each of ninety-four 3 h EEG recordings on 52 healthy neonates from 29 to 43 weeks 3A (28 pre-term (PT)/24 full-term (FT)); 51 who are neurodevelopmentally normal up to at least 18 months of age. Each recording was reviewed to identify positive temporal sharp waves (PTS). This wave form was compared to another commonly occurring wave form, temporal theta of prematurity (PTΘ). 588 PTS and 626 PTΘ observations were tabulated in terms of frequency, amplitude, morphology, left: right predominance, and sleep state at 6 post-conceptional age ranges up to term. Mean PTS for FT, PT and pre-term at post-conceptional term age (PTT) infants, respectively, were 1.5 ± 0.85, 2.8 ± 2.5, 2.0 ± 1.6 per sleep cycle. PTS amplitudes (μV) were 59.7 ± 23.5, 38.2 ± 17.8, and 51.8 ± 29.3. The peak incidence of PTS occurs at older post-conceptional ages than PTΘ ( r = 0.21, P = 0.0001). PTT infants had more PTS ( X 2 = 32.5, P = 0.001) than FT infants. Similar numbers and descriptions of PTΘ were noted between neonatal groups at post-conceptional term ages. While pathological PTS waves have been described in FT neonates and infants (Chung and Clancy: Electroenceph. clin. Neurophysiol., 1991, 79: 256–263), benign PTS waves are also present on recordings of healthy pre-term and full-term neonates. PTS are electrographically similar to PTΘ, but are more EEGs of healthy neonates will improve the assessment of encephalopathic recordings obtained for clinical reasons. Persistence of PTS at post-conceptional term ages in the pre-term group may reflect an alteration in brain maturation because of prematurity or the extrauterine experience. Increased numbers of this pattern at post-conceptional term ages reflect transient brain Dysmaturity in an otherwise asymptomatic infant.
Laetitia E. M. Niers - One of the best experts on this subject based on the ideXlab platform.
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Aminoacyl-tRNA synthetase deficiencies in search of common themes
Genetics in Medicine, 2019Co-Authors: Sabine A. Fuchs, Imre F. Schene, Jurriaan M. Jansen, Peter G. J. Nikkels, Koen L. I. Gassen, Suzanne W. J. Terheggen-lagro, Saskia N. Crabben, Sanne E. Hoeks, Laetitia E. M. Niers, Nicole I. WolfAbstract:Purpose Pathogenic variations in genes encoding aminoacyl-tRNA synthetases (ARSs) are increasingly associated with human disease. Clinical features of autosomal recessive ARS deficiencies appear very diverse and without apparent logic. We searched for common clinical patterns to improve disease recognition, insight into pathophysiology, and clinical care. Methods Symptoms were analyzed in all patients with recessive ARS deficiencies reported in literature, supplemented with unreported patients evaluated in our hospital. Results In literature, we identified 107 patients with AARS, DARS, GARS, HARS, IARS, KARS, LARS, MARS, RARS, SARS, VARS, YARS, and QARS deficiencies. Common symptoms (defined as present in ≥4/13 ARS deficiencies) included abnormalities of the central nervous system and/or senses (13/13), failure to thrive, gastrointestinal symptoms, Dysmaturity, liver disease, and facial dysmorphisms. Deep phenotyping of 5 additional patients with unreported compound heterozygous pathogenic variations in IARS , LARS , KARS , and QARS extended the common phenotype with lung disease, hypoalbuminemia, anemia, and renal tubulopathy. Conclusion We propose a common clinical phenotype for recessive ARS deficiencies, resulting from insufficient aminoacylation activity to meet translational demand in specific organs or periods of life. Assuming residual ARS activity, adequate protein/amino acid supply seems essential instead of the traditional replacement of protein by glucose in patients with metabolic diseases.
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aminoacyl trna synthetase deficiencies in search of common themes
Genetics in Medicine, 2019Co-Authors: Sabine A. Fuchs, Imre F. Schene, Jurriaan M. Jansen, Peter G. J. Nikkels, Gautam Kok, Koen L I Van Gassen, Suzanne W J Terheggenlagro, Saskia N Van Der Crabben, Sanne B E A Hoeks, Laetitia E. M. NiersAbstract:Pathogenic variations in genes encoding aminoacyl-tRNA synthetases (ARSs) are increasingly associated with human disease. Clinical features of autosomal recessive ARS deficiencies appear very diverse and without apparent logic. We searched for common clinical patterns to improve disease recognition, insight into pathophysiology, and clinical care. Symptoms were analyzed in all patients with recessive ARS deficiencies reported in literature, supplemented with unreported patients evaluated in our hospital. In literature, we identified 107 patients with AARS, DARS, GARS, HARS, IARS, KARS, LARS, MARS, RARS, SARS, VARS, YARS, and QARS deficiencies. Common symptoms (defined as present in ≥4/13 ARS deficiencies) included abnormalities of the central nervous system and/or senses (13/13), failure to thrive, gastrointestinal symptoms, Dysmaturity, liver disease, and facial dysmorphisms. Deep phenotyping of 5 additional patients with unreported compound heterozygous pathogenic variations in IARS, LARS, KARS, and QARS extended the common phenotype with lung disease, hypoalbuminemia, anemia, and renal tubulopathy. We propose a common clinical phenotype for recessive ARS deficiencies, resulting from insufficient aminoacylation activity to meet translational demand in specific organs or periods of life. Assuming residual ARS activity, adequate protein/amino acid supply seems essential instead of the traditional replacement of protein by glucose in patients with metabolic diseases.
Sabine A. Fuchs - One of the best experts on this subject based on the ideXlab platform.
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Aminoacyl-tRNA synthetase deficiencies in search of common themes
Genetics in Medicine, 2019Co-Authors: Sabine A. Fuchs, Imre F. Schene, Jurriaan M. Jansen, Peter G. J. Nikkels, Koen L. I. Gassen, Suzanne W. J. Terheggen-lagro, Saskia N. Crabben, Sanne E. Hoeks, Laetitia E. M. Niers, Nicole I. WolfAbstract:Purpose Pathogenic variations in genes encoding aminoacyl-tRNA synthetases (ARSs) are increasingly associated with human disease. Clinical features of autosomal recessive ARS deficiencies appear very diverse and without apparent logic. We searched for common clinical patterns to improve disease recognition, insight into pathophysiology, and clinical care. Methods Symptoms were analyzed in all patients with recessive ARS deficiencies reported in literature, supplemented with unreported patients evaluated in our hospital. Results In literature, we identified 107 patients with AARS, DARS, GARS, HARS, IARS, KARS, LARS, MARS, RARS, SARS, VARS, YARS, and QARS deficiencies. Common symptoms (defined as present in ≥4/13 ARS deficiencies) included abnormalities of the central nervous system and/or senses (13/13), failure to thrive, gastrointestinal symptoms, Dysmaturity, liver disease, and facial dysmorphisms. Deep phenotyping of 5 additional patients with unreported compound heterozygous pathogenic variations in IARS , LARS , KARS , and QARS extended the common phenotype with lung disease, hypoalbuminemia, anemia, and renal tubulopathy. Conclusion We propose a common clinical phenotype for recessive ARS deficiencies, resulting from insufficient aminoacylation activity to meet translational demand in specific organs or periods of life. Assuming residual ARS activity, adequate protein/amino acid supply seems essential instead of the traditional replacement of protein by glucose in patients with metabolic diseases.
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aminoacyl trna synthetase deficiencies in search of common themes
Genetics in Medicine, 2019Co-Authors: Sabine A. Fuchs, Imre F. Schene, Jurriaan M. Jansen, Peter G. J. Nikkels, Gautam Kok, Koen L I Van Gassen, Suzanne W J Terheggenlagro, Saskia N Van Der Crabben, Sanne B E A Hoeks, Laetitia E. M. NiersAbstract:Pathogenic variations in genes encoding aminoacyl-tRNA synthetases (ARSs) are increasingly associated with human disease. Clinical features of autosomal recessive ARS deficiencies appear very diverse and without apparent logic. We searched for common clinical patterns to improve disease recognition, insight into pathophysiology, and clinical care. Symptoms were analyzed in all patients with recessive ARS deficiencies reported in literature, supplemented with unreported patients evaluated in our hospital. In literature, we identified 107 patients with AARS, DARS, GARS, HARS, IARS, KARS, LARS, MARS, RARS, SARS, VARS, YARS, and QARS deficiencies. Common symptoms (defined as present in ≥4/13 ARS deficiencies) included abnormalities of the central nervous system and/or senses (13/13), failure to thrive, gastrointestinal symptoms, Dysmaturity, liver disease, and facial dysmorphisms. Deep phenotyping of 5 additional patients with unreported compound heterozygous pathogenic variations in IARS, LARS, KARS, and QARS extended the common phenotype with lung disease, hypoalbuminemia, anemia, and renal tubulopathy. We propose a common clinical phenotype for recessive ARS deficiencies, resulting from insufficient aminoacylation activity to meet translational demand in specific organs or periods of life. Assuming residual ARS activity, adequate protein/amino acid supply seems essential instead of the traditional replacement of protein by glucose in patients with metabolic diseases.
Kenneth A Loparo - One of the best experts on this subject based on the ideXlab platform.
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physiologic brain Dysmaturity in late preterm infants
Pediatric Research, 2011Co-Authors: Mark S Scher, Mark W Johnson, Susan M Ludington, Kenneth A LoparoAbstract:Neonatal EEG sleep was used to determine whether differences are expressed between healthy late preterm and full-term (FT) groups. Twenty-seven 24-channel multihour studies were recorded at similar postmenstrual ages (PMA) and analyzed for eight asymptomatic late preterm infants (LPT) compared with 19 healthy FT infants as a preliminary analysis, followed by a comparison of a subset of eight FT infants, matched for gender, race, and PMA. Z scores were performed on data sets from each group pair comparing each of seven EEG/Sleep measures for entire recordings, active sleep (AS) and quiet sleep (QS) segments and artifact-free intervals. Six of seven measures showed differences between the eight LPT and eight matched FT cohort pair comparisons of >0.3; rapid eye movements, arousals during QS, spectral correlations between homologous centrotemporal regions during QS, spectral beta/alpha power ratios during AS and QS, a spectral measure of respiratory regularity during QS, and sleep cycle length. Quantitative neurophysiologic analyses define differences in brain maturation between LPT and FT infants at similar PMA. Altered EEG/Sleep behaviors in the LPT are biomarkers of developmental neuroplasticity involving interconnected neuronal networks adapting to conditions of prematurity for this largest segment of the preterm neonatal population.
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automated detection of neonate eeg sleep stages
Computer Methods and Programs in Biomedicine, 2009Co-Authors: Alexandra Piryatinska, Mark S Scher, Gyorgy Terdik, Wojbor A Woyczynski, Kenneth A Loparo, Anatoly ZlotnikAbstract:The paper integrates and adapts a range of advanced computational, mathematical and statistical tools for the purpose of analysis of neonate sleep stages based on extensive electroencephalogram (EEG) recordings. The level of brain Dysmaturity of a neonate is difficult to assess by direct physical or cognitive examination, but Dysmaturity is known to be directly related to the structure of neonatal sleep as reflected in the nonstationary time series produced by EEG signals which, importantly, can be collected trough a noninvasive procedure. In the past, the assessment of sleep EEG structure has often been done manually by experienced clinicians. The goal of this paper is to develop rigorous algorithmic tools for the same purpose by providing a formal scheme to separate different sleep stages corresponding to different stationary segments of the EEG signal based on statistical analysis of the spectral and nonlinear characteristics of the sleep EEG recordings. The methods developed in this paper can, potentially, be translated to other areas of biomedical research.
Nicole I. Wolf - One of the best experts on this subject based on the ideXlab platform.
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Aminoacyl-tRNA synthetase deficiencies in search of common themes
Genetics in Medicine, 2019Co-Authors: Sabine A. Fuchs, Imre F. Schene, Jurriaan M. Jansen, Peter G. J. Nikkels, Koen L. I. Gassen, Suzanne W. J. Terheggen-lagro, Saskia N. Crabben, Sanne E. Hoeks, Laetitia E. M. Niers, Nicole I. WolfAbstract:Purpose Pathogenic variations in genes encoding aminoacyl-tRNA synthetases (ARSs) are increasingly associated with human disease. Clinical features of autosomal recessive ARS deficiencies appear very diverse and without apparent logic. We searched for common clinical patterns to improve disease recognition, insight into pathophysiology, and clinical care. Methods Symptoms were analyzed in all patients with recessive ARS deficiencies reported in literature, supplemented with unreported patients evaluated in our hospital. Results In literature, we identified 107 patients with AARS, DARS, GARS, HARS, IARS, KARS, LARS, MARS, RARS, SARS, VARS, YARS, and QARS deficiencies. Common symptoms (defined as present in ≥4/13 ARS deficiencies) included abnormalities of the central nervous system and/or senses (13/13), failure to thrive, gastrointestinal symptoms, Dysmaturity, liver disease, and facial dysmorphisms. Deep phenotyping of 5 additional patients with unreported compound heterozygous pathogenic variations in IARS , LARS , KARS , and QARS extended the common phenotype with lung disease, hypoalbuminemia, anemia, and renal tubulopathy. Conclusion We propose a common clinical phenotype for recessive ARS deficiencies, resulting from insufficient aminoacylation activity to meet translational demand in specific organs or periods of life. Assuming residual ARS activity, adequate protein/amino acid supply seems essential instead of the traditional replacement of protein by glucose in patients with metabolic diseases.