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Nobuhiro Yuki - One of the best experts on this subject based on the ideXlab platform.
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hyperReflexia in guillain barre syndrome relation with acute motor axonal neuropathy and anti gm1 antibody
Journal of Neurology Neurosurgery and Psychiatry, 1999Co-Authors: Satoshi Kuwabara, Kazue Ogawara, Michiaki Koga, Masahiro Mori, Takamichi Hattori, Nobuhiro YukiAbstract:OBJECTIVES—To investigate the incidence of hyperReflexia in patients with Guillain-Barre syndrome (GBS), and its relation with electrodiagnosis of acute motor axonal neuropathy (AMAN), antiganglioside GM1 antibody, and Campylobacter jejuni infection. It was reported that patients with AMAN in northern China often had hyperReflexia in the recovery phase. METHODS—In 54 consecutive Japanese patients with GBS, sequential findings of tendon Reflexes were reviewed. By electrodiagnostic criteria, patients were classified as having AMAN or acute inflammatory demyelinating polyneuropathy (AIDP). Anti-GM1 and anti-C jejuni antibodies were measured by enzyme linked immunosorbent assays. RESULTS—Seven (13%) patients developed hyperReflexia with the spread of the Myotatic Reflex to other segments in the early recovery phase, one of whom already had hyperReflexia in the acute progressive phase. Of the seven patients, six had AMAN and all seven had anti-GM1 antibodies, whereas only two had anti-C jejuni antibodies. HyperReflexia was more often found in patients with AMAN than AIDP (6/23 v 1/18, p=0.002), and in patients with anti-GM1 antibodies than without them (7/26 v 0/28, p=0.01). HyperReflexic patients had milder peak disabilities than patients without hyperReflexia (p=0.03). Increased motor neuron excitability in the hyperReflexic patients was supported by increased soleus H-Reflex amplitudes and the appearance of H-Reflexes in the small hand or foot muscles. CONCLUSIONS—HyperReflexia often occurs in patients with GBS especially with AMAN, anti-GM1 antibodies, and milder disease. Increased motor neuron excitability further characterises the subgroup of patients with GBS with AMAN and anti-GM1 antibodies.
Charles T Leonard - One of the best experts on this subject based on the ideXlab platform.
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Myotatic Reflex responses of non disabled children and children with spastic cerebral palsy
Developmental Medicine & Child Neurology, 2008Co-Authors: Charles T Leonard, Helia HirschfeldAbstract:SUMMARY Surface electromyography (EMG) was used to examine lower-extremity Myotatic Reflex responses following patellar or Achilles tendon taps to normally developing, non-disabled infants and to individuals with cerebral palsy (CP). Reflex irradiation was present in non-disabled infants and infants with CP under two years of age. The only significant differences in Myotatic Reflex responses between the two groups at this age was the higher amplitude of the directly stimulated muscle of children with CP. After two years the amplitude did not differ between groups. Reflex irradiation, however, was greatly reduced in the non-disabled children but not in the children with cerebral palsy. These findings and those of non-human animal studies indicate the possible neural mechanisms that underlie Reflex irradiation of individuals with CP. The potential clinical relevance of these findings is discussed. RESUME Reponses Reflexes myotatiques chez les enfants valides e IMC spastiques Une electromyographic de surface (EMG) a ete utilisee pour examiner les responses Reflexes myotatiques des membres inferieurs apres percussiopn des tendons rotulicns et achilleens chez des nourrissons valides en developpemenl et des IMC. Une irradiation Reflexe etait presente chez les mourrissons valides et IMC de moins de deux ans. La seule difference significative dans les responses myotatiques Reflexes entre les deux groupes concernait la plus grande amplitude de reponse du muscle stimule directement chez l'enfant IMC; apres deux ans, l'amplitude ne differait pas entre les deux groupes. L'irradiation Reflexe, cependant, etait grandement reduite chez les enfants valides et non chez les enfants IMC. Ces donnees e tcclles obtenues chez les animaux indique les mecanismes neuronaux qui pourraient expliquer L'irradiation Reflexe chez les IMC. Les consequences cliniques potentielles de cettc etude sont discutees. ZUSAMMENFASSUNG StreckReflexreaktionen bci nicht behindvrien Kindern und bei Kindern mil spaslischcr Cerebralparese Mit Hilfe de Oberflachen-Elektromyographie (EMG) wurden die StreckReflexreaktionen der unteren Extremitat, asugelost durch Bekopfen de Patellar- oder Achillessehne, bei sich normal entwickelnden, nicht behinderten Kindern und bei Patienten mit Cerebralparesc (CP) unlersucht. Bei den nichi behinderten Kindern und bei den Patienten mit CP unier zwei Jahren war eine Reflexausbreitung vorhanden. Der einzige signifikante Unterschied bei den StreckReflexreaktionen zwischen den beiden Gruppen in dieser Altersstufe bestand in einer hoheren Amplitude des direkt stimulierten Muskels bei den Kindern mit CP; nach dem zweiten Lebensjahr fand sich kein Amplitudenunterschied zweischen den beiden Gruppen. Die Reflexausbreitung jedoch reduzierte sich bei den nicht behinderten Kindern deutlich, bei den Patienten mit CP aber nicht. Diese Befunde und Ergcbnisse aus Tierstudien zeigen mogliche neurale Mechanismen an, die der Reflexausbreitung bei Patienten mit CP zugrunde liegen. Die potentillle klinische Relcvanz dieser Befunde wird diskutiert. RESUMEN Respuestas rcflejas miotaticas en ninos sin discapacidad y en ninos con paralisis cerebral de tipo espastico Se utilizo la EMG de superficie para examinar el reflejo miotatico en las extremidades interiores, al golpear el tendon patelar o el de Aquiles en ninos con un desarrollo normal no discapacitados y en ninos con paralisis cerebral (PC). En ambos grupos existia una irradiacion del retlcjo por debajo de los dos anos de edad. La uUnica diferencia significativa en la respuesta miotatica de ambos grupos a esta edad era una mayor amplitud del musculo directamente estimulado en ninos con PC. Despues de los dos anos, la amplitud no diferia en los dos grupos. La irradiacion del reflejo sin embargo, se reducia mucho en los ninos no discapacitados pero no en los que tenfan PC. Estos hallazgos, y los obtenidos en animates, indican los posibles mecanismos neuronales que subyacen en la irradiacion refleja en los individuos con PC. Se discute la importancia clinical potencial de estos hallazgos.
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human Myotatic Reflex development of the lower extremities
Early Human Development, 1995Co-Authors: Charles T Leonard, Tamaki Matsumoto, P M DiedrichAbstract:Abstract Lower extremity (LE) Myotatic Reflexes were tested by percussion (taps) to the patellar and Achilles tendons. Surface electromyographic recordings were obtained from 5 LE muscles during tendon taps. Results indicated that LE Myotatic Reflexes underwent considerable change during early human development. The changes were non-linear and highly variable. Reflex irradiation (the presence of Reflex responses in muscles other than the one being directly stimulated by a tendon tap) was present in the newborn but to a lesser extent than was in evidence later on during the first year of life. The percentage of time Reflex irradiation was detected in heteronymous muscle groups appeared to achieve maximal levels during the first year and then progressively decline. The decline in Reflex irradiation was most dramatic between the first and second years of life. Irradiated responses were still recorded from 2 year-old children but with less frequency than in children less than 1 year of age. With the exception of responses in muscles that were direct antagonists to the stimulated muscle, irradiation was not observed in children 3–5 years of age.
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Myotatic Reflex development in normal children and children with cerebral palsy
Experimental Neurology, 1991Co-Authors: Charles T Leonard, Helia Hirschfeld, Toshio Moritani, Hans ForssbergAbstract:Neonatal neuronal exuberance and its retention following neonatal brain damage have been demonstrated in a number of species but not in humans. The purpose of the present ongoing study is to determine if there is any evidence of neonatal neuronal exuberance and its retention following damage to the CNS in the human. Of equal concern is the determination of the neurological mechanisms underlying abnormal movement and Reflex development in children with cerebral palsy.
Helia Hirschfeld - One of the best experts on this subject based on the ideXlab platform.
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Myotatic Reflex responses of non disabled children and children with spastic cerebral palsy
Developmental Medicine & Child Neurology, 2008Co-Authors: Charles T Leonard, Helia HirschfeldAbstract:SUMMARY Surface electromyography (EMG) was used to examine lower-extremity Myotatic Reflex responses following patellar or Achilles tendon taps to normally developing, non-disabled infants and to individuals with cerebral palsy (CP). Reflex irradiation was present in non-disabled infants and infants with CP under two years of age. The only significant differences in Myotatic Reflex responses between the two groups at this age was the higher amplitude of the directly stimulated muscle of children with CP. After two years the amplitude did not differ between groups. Reflex irradiation, however, was greatly reduced in the non-disabled children but not in the children with cerebral palsy. These findings and those of non-human animal studies indicate the possible neural mechanisms that underlie Reflex irradiation of individuals with CP. The potential clinical relevance of these findings is discussed. RESUME Reponses Reflexes myotatiques chez les enfants valides e IMC spastiques Une electromyographic de surface (EMG) a ete utilisee pour examiner les responses Reflexes myotatiques des membres inferieurs apres percussiopn des tendons rotulicns et achilleens chez des nourrissons valides en developpemenl et des IMC. Une irradiation Reflexe etait presente chez les mourrissons valides et IMC de moins de deux ans. La seule difference significative dans les responses myotatiques Reflexes entre les deux groupes concernait la plus grande amplitude de reponse du muscle stimule directement chez l'enfant IMC; apres deux ans, l'amplitude ne differait pas entre les deux groupes. L'irradiation Reflexe, cependant, etait grandement reduite chez les enfants valides et non chez les enfants IMC. Ces donnees e tcclles obtenues chez les animaux indique les mecanismes neuronaux qui pourraient expliquer L'irradiation Reflexe chez les IMC. Les consequences cliniques potentielles de cettc etude sont discutees. ZUSAMMENFASSUNG StreckReflexreaktionen bci nicht behindvrien Kindern und bei Kindern mil spaslischcr Cerebralparese Mit Hilfe de Oberflachen-Elektromyographie (EMG) wurden die StreckReflexreaktionen der unteren Extremitat, asugelost durch Bekopfen de Patellar- oder Achillessehne, bei sich normal entwickelnden, nicht behinderten Kindern und bei Patienten mit Cerebralparesc (CP) unlersucht. Bei den nichi behinderten Kindern und bei den Patienten mit CP unier zwei Jahren war eine Reflexausbreitung vorhanden. Der einzige signifikante Unterschied bei den StreckReflexreaktionen zwischen den beiden Gruppen in dieser Altersstufe bestand in einer hoheren Amplitude des direkt stimulierten Muskels bei den Kindern mit CP; nach dem zweiten Lebensjahr fand sich kein Amplitudenunterschied zweischen den beiden Gruppen. Die Reflexausbreitung jedoch reduzierte sich bei den nicht behinderten Kindern deutlich, bei den Patienten mit CP aber nicht. Diese Befunde und Ergcbnisse aus Tierstudien zeigen mogliche neurale Mechanismen an, die der Reflexausbreitung bei Patienten mit CP zugrunde liegen. Die potentillle klinische Relcvanz dieser Befunde wird diskutiert. RESUMEN Respuestas rcflejas miotaticas en ninos sin discapacidad y en ninos con paralisis cerebral de tipo espastico Se utilizo la EMG de superficie para examinar el reflejo miotatico en las extremidades interiores, al golpear el tendon patelar o el de Aquiles en ninos con un desarrollo normal no discapacitados y en ninos con paralisis cerebral (PC). En ambos grupos existia una irradiacion del retlcjo por debajo de los dos anos de edad. La uUnica diferencia significativa en la respuesta miotatica de ambos grupos a esta edad era una mayor amplitud del musculo directamente estimulado en ninos con PC. Despues de los dos anos, la amplitud no diferia en los dos grupos. La irradiacion del reflejo sin embargo, se reducia mucho en los ninos no discapacitados pero no en los que tenfan PC. Estos hallazgos, y los obtenidos en animates, indican los posibles mecanismos neuronales que subyacen en la irradiacion refleja en los individuos con PC. Se discute la importancia clinical potencial de estos hallazgos.
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Myotatic Reflex development in normal children and children with cerebral palsy
Experimental Neurology, 1991Co-Authors: Charles T Leonard, Helia Hirschfeld, Toshio Moritani, Hans ForssbergAbstract:Neonatal neuronal exuberance and its retention following neonatal brain damage have been demonstrated in a number of species but not in humans. The purpose of the present ongoing study is to determine if there is any evidence of neonatal neuronal exuberance and its retention following damage to the CNS in the human. Of equal concern is the determination of the neurological mechanisms underlying abnormal movement and Reflex development in children with cerebral palsy.
Satoshi Kuwabara - One of the best experts on this subject based on the ideXlab platform.
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hyperReflexia in guillain barre syndrome relation with acute motor axonal neuropathy and anti gm1 antibody
Journal of Neurology Neurosurgery and Psychiatry, 1999Co-Authors: Satoshi Kuwabara, Kazue Ogawara, Michiaki Koga, Masahiro Mori, Takamichi Hattori, Nobuhiro YukiAbstract:OBJECTIVES—To investigate the incidence of hyperReflexia in patients with Guillain-Barre syndrome (GBS), and its relation with electrodiagnosis of acute motor axonal neuropathy (AMAN), antiganglioside GM1 antibody, and Campylobacter jejuni infection. It was reported that patients with AMAN in northern China often had hyperReflexia in the recovery phase. METHODS—In 54 consecutive Japanese patients with GBS, sequential findings of tendon Reflexes were reviewed. By electrodiagnostic criteria, patients were classified as having AMAN or acute inflammatory demyelinating polyneuropathy (AIDP). Anti-GM1 and anti-C jejuni antibodies were measured by enzyme linked immunosorbent assays. RESULTS—Seven (13%) patients developed hyperReflexia with the spread of the Myotatic Reflex to other segments in the early recovery phase, one of whom already had hyperReflexia in the acute progressive phase. Of the seven patients, six had AMAN and all seven had anti-GM1 antibodies, whereas only two had anti-C jejuni antibodies. HyperReflexia was more often found in patients with AMAN than AIDP (6/23 v 1/18, p=0.002), and in patients with anti-GM1 antibodies than without them (7/26 v 0/28, p=0.01). HyperReflexic patients had milder peak disabilities than patients without hyperReflexia (p=0.03). Increased motor neuron excitability in the hyperReflexic patients was supported by increased soleus H-Reflex amplitudes and the appearance of H-Reflexes in the small hand or foot muscles. CONCLUSIONS—HyperReflexia often occurs in patients with GBS especially with AMAN, anti-GM1 antibodies, and milder disease. Increased motor neuron excitability further characterises the subgroup of patients with GBS with AMAN and anti-GM1 antibodies.
Suresh R Devasahayam - One of the best experts on this subject based on the ideXlab platform.
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f189 reciprocal excitation a hidden component of the Myotatic stretch Reflex
Clinical Neurophysiology, 2018Co-Authors: Anandi J Mathew, Syrpailyne Wankha, Suresh R DevasahayamAbstract:Introduction The Myotatic Reflex (MR) and Reciprocal Inhibition (RI) are well documented phenomena. They fit well into the framework of negative feedback control of muscle length and complementary control of movement by opposite groups of muscles. Reciprocal excitation (RE) has been reported intermittently and controversially, only in patients with spasticity of various forms. While using quantitative measures of the MR, we recorded clear and consistent electrical evidence of RE in normal subjects. Our experiments show that the standard textbook model of the MR is in fact incomplete. In this paper we present experimental evidence confirming the presence of RE as a spinal Reflex, in normal subjects. Methods Three methods were used to elicit the MR of the quadriceps muscle: the patellar tendon tap, rapid mechanical flexion at the knee, electrical stimulation of the femoral nerve. The electrical response from the agonist and antagonist muscles were recorded simultaneously using surface EMG. Following the stretch of the quadriceps, the Reflex excitation from the quadriceps and a smaller excitation from the hamstrings was recorded. Mechanical artefacts and cross-pickup from neighbouring muscles were excluded. Data from 28 normal subjects was processed and analysed with custom programs in Python. The mechanical stretch stimulus was the flexion at the knee lasting roughly 100 ms making it difficult to identify a single time-point of stretch stimulus. On electrical stimulation of the femoral nerve in the femoral triangle it was difficult to separate the Reflex wave from the stimulation artefact as most subjects required strong stimulus. Results Excitation of the heteronymous group of muscles as a component of the MR in normal subjects has been clearly observed in our experiments. Though this excitation is around 10% of the primary Reflex excitation, its latency and reproducibility confirm its physiological origin as a spinal Reflex. The patellar tendon tap latency(ms) and amplitude(mV) ranges averaged over 25 trials for each of the 28 subjects, seen distinct from background noise are, respectively: Rectusfemoris = 15–22, 0.0473–2.1503; Bicepsfemoris = 17–33, 0.0076–0.3462, Semitendinosus = 17–33, 0.003–0.2015. The recordings with mechanical stretch and electrical stimulation of the femoral nerve confirm distinct RE in the hamstrings. Conclusion There are a few reports of RE in spasticity. We have demonstrated its presence in normal subjects. The coexcitation of the antagonist at the same time as the agonist may play an important role in providing stability around a joint to prevent injuries when there is rapid stretch of the agonist. Our data suggests that further studies are required to understand its neuronal pathway, relevance and potential clinical use in normal subjects and pathology.
