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1.
Endocr J ; 69(2): 173-177, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-34544941

RESUMEN

A 28-year-old Japanese woman positive for TSH receptor antibody and anti-nuclear antibody complained of difficulty seeing nearby objects, severe throbbing retro-orbital pain, diplopia, blepharoptosis and upward gaze palsy when she became hypothyroid during treatment with 30 mg methylmercaptoimidazole for Graves' hyperthyroidism. Brain magnetic resonance imaging revealed slightly swollen bilateral inferior rectus muscles, suggesting the external ophthalmoplegia due to the muscle pathology commonly encountered in Graves' disease. The retro-orbital pain was associated with marked accommodation failure and the pupillary abnormalities. The left and/or right eye showed intermittent, asymmetric and fluctuating mydriasis, being unresponsive to ordinary light but slowly responsive to strong sunlight and slowly responsive in a dark room. During the 5-year period, mydriasis was observed 9 times on both sides, 11 times only on the right side and 4 times only on the left side. Internal ophthalmoplegia with tonic pupils and accommodation failure affecting both the pupillary sphincter muscle and ciliary muscle due to damage to the parasympathetic outflow to these muscles was suggested. Autoimmune mechanism and/or the mechanism underlying channelopathy affecting the ciliary ganglion or short ciliary nerves might be responsible for this fluctuating complication. This very rare panophthalmopathy affecting both external and internal muscles occurred when the patient was suffering from iatrogenic hypothyroidism during the 30 mg methylmercaptimidazole treatment for Graves' disease.


Asunto(s)
Enfermedad de Graves , Oftalmopatía de Graves , Oftalmoplejía , Adulto , Femenino , Enfermedad de Graves/complicaciones , Enfermedad de Graves/tratamiento farmacológico , Oftalmopatía de Graves/patología , Humanos , Imagen por Resonancia Magnética , Metimazol , Oftalmoplejía/tratamiento farmacológico , Oftalmoplejía/etiología
2.
Mov Disord ; 34(11): 1602-1613, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31584223

RESUMEN

Genetically determined myoclonus disorders are a result of a large number of genes. They have wide clinical variation and no systematic nomenclature. With next-generation sequencing, genetic diagnostics require stringent criteria to associate genes and phenotype. To improve (future) classification and recognition of genetically determined movement disorders, the Movement Disorder Society Task Force for Nomenclature of Genetic Movement Disorders (2012) advocates and renews the naming system of locus symbols. Here, we propose a nomenclature for myoclonus syndromes and related disorders with myoclonic jerks (hyperekplexia and myoclonic epileptic encephalopathies) to guide clinicians in their diagnostic approach to patients with these disorders. Sixty-seven genes were included in the nomenclature. They were divided into 3 subgroups: prominent myoclonus syndromes, 35 genes; prominent myoclonus syndromes combined with another prominent movement disorder, 9 genes; disorders that present usually with other phenotypes but can manifest as a prominent myoclonus syndrome, 23 genes. An additional movement disorder is seen in nearly all myoclonus syndromes: ataxia (n = 41), ataxia and dystonia (n = 6), and dystonia (n = 5). However, no additional movement disorders were seen in related disorders. Cognitive decline and epilepsy are present in the vast majority. The anatomical origin of myoclonus is known in 64% of genetic disorders: cortical (n = 34), noncortical areas (n = 8), and both (n = 1). Cortical myoclonus is commonly seen in association with ataxia, and noncortical myoclonus is often seen with myoclonus-dystonia. This new nomenclature of myoclonus will guide diagnostic testing and phenotype classification. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Distonía/genética , Trastornos Distónicos/genética , Enfermedad de Parkinson/genética , Trastornos Parkinsonianos/genética , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/genética , Distonía/diagnóstico , Trastornos Distónicos/diagnóstico , Humanos , Enfermedad de Parkinson/diagnóstico , Trastornos Parkinsonianos/diagnóstico , Fenotipo
3.
Biosci Biotechnol Biochem ; 82(9): 1468-1472, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29912640

RESUMEN

Female sex pheromone of a clearwing moth Nokona feralis (Leech) (Lepidoptera: Sesiidae), a pest of kiwifruit, was identified to be a 7:3 mixture of (3E,13Z)-3,13-octadecadienyl acetate (E3,Z13-18:OAc) and (3E,13Z)-3,13-octadecadien-1-ol (E3,Z13-18:OH) by GC-EAD and GC/MS analyses. Males were attracted to wide-range mixtures of E3,Z13-18:OAc and E3,Z13-18:OH, and a 7:3 mixture of those two compounds strongly attracted the males in the field.


Asunto(s)
Actinidia/parasitología , Lepidópteros/fisiología , Atractivos Sexuales/análisis , Animales , Femenino , Cromatografía de Gases y Espectrometría de Masas , Masculino , Atractivos Sexuales/fisiología , Conducta Sexual Animal
4.
J Chem Ecol ; 39(3): 350-7, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23400496

RESUMEN

The nettle moth Monema flavescens (Limacodidae) is a defoliator of fruit trees, such as Chinese plum and persimmon. The larvae of this species have spines containing a poison that causes serious irritation and inflammation in humans. Coupled gas chromatography-electroantennogram detection and gas chromatography/mass spectrometry analyses of a crude pheromone extract, combined with derivatization, indicated that female moths produced 8-decen-1-ol and 7,9-decadien-1-ol at a ratio of approximately 9:1. The E configuration of the double bonds was assigned for both components from infrared spectra, recorded on a gas chromatograph/Fourier transform-infrared spectrophotometer equipped with a zinc selenide disk cooled to -30 °C. The monoenyl and dienyl alcohols had absorptions characteristic of E geometry at 966 and 951 cm(-1), respectively. A band chromatogram at 951 cm(-1) was useful for distinguishing geometric isomers, because terminal conjugated diene are difficult to resolve, even on high polarity columns. Furthermore, we identified the Z configuration of the same 7,9-dienyl alcohol secreted by another nettle moth, Parasa lepida lepida, through the absence of this absorption. In field trials, lures baited with a 9:1 mixture of (E)-8-decen-1-ol and (E)-7,9-decadien-1-ol attracted M. flavescens males. Furthermore, the field trials indicated that contamination with the (Z)-diene reduced catches to the pheromone mixture more than did contamination with the (Z)-monoene.


Asunto(s)
Mariposas Nocturnas/química , Mariposas Nocturnas/metabolismo , Atractivos Sexuales/análisis , Atractivos Sexuales/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Animales , Conducta Animal/efectos de los fármacos , Cromatografía de Gases , Femenino , Masculino , Mariposas Nocturnas/efectos de los fármacos , Compuestos de Selenio/química , Atractivos Sexuales/síntesis química , Atractivos Sexuales/farmacología , Compuestos de Zinc/química
5.
Hum Brain Mapp ; 33(12): 2856-72, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21928311

RESUMEN

Parieto-frontal network is essential for sensorimotor integration in various complex behaviors, and its disruption is associated with pathophysiology of apraxia and visuo-spatial disorders. Despite advances in knowledge regarding specialized cortical areas for various sensorimotor transformations, little is known about the underlying cortico-cortical connectivity in humans. We investigated inter-areal connections of the lateral parieto-frontal network in vivo by means of cortico-cortical evoked potentials (CCEPs). Six patients with epilepsy and one with brain tumor were studied. With the use of subdural electrodes implanted for presurgical evaluation, network configuration was investigated by tracking the connections from the parietal stimulus site to the frontal site where the maximum CCEP was recorded. It was characterized by (i) a near-to-near and distant-to-distant, mirror symmetric configuration across the central sulcus, (ii) preserved dorso-ventral organization (the inferior parietal lobule to the ventral premotor area and the superior parietal lobule to the dorsal premotor area), and (iii) projections to more than one frontal cortical sites in 56% of explored connections. These findings were also confirmed by the standardized parieto-frontal CCEP connectivity map constructed in reference to the Jülich cytoarchitectonic atlas in the MNI standard space. The present CCEP study provided an anatomical blueprint underlying the lateral parieto-frontal network and demonstrated a connectivity pattern similar to non-human primates in the newly developed inferior parietal lobule in humans.


Asunto(s)
Potenciales Evocados/fisiología , Lóbulo Frontal/fisiología , Red Nerviosa/fisiología , Lóbulo Parietal/fisiología , Adolescente , Adulto , Estimulación Eléctrica , Epilepsias Parciales/fisiopatología , Femenino , Lóbulo Frontal/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Red Nerviosa/fisiopatología , Vías Nerviosas/fisiología , Vías Nerviosas/fisiopatología , Lóbulo Parietal/fisiopatología
6.
J Chem Ecol ; 38(8): 1042-9, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22836826

RESUMEN

Cis-9,10-epoxy-(3Z,6Z)-1,3,6-henicosatriene has been identified from a pheromone gland of arctiid species, such as Hyphantria cunea. Since the diversity of lepidopteran species suggests that structurally related compounds of the 9,10-epoxide are also utilized as a sex pheromone components, epoxytrienes derived from (3Z,6Z,9Z)-1,3,6,9-tetraenes with a C(19)-C(21) chain were systematically synthesized and characterized. While 1,2-epoxy-3,6,9-triene was not obtained, peracid oxidation of each tetraene produced a mixture of three cis-epoxides (3,4-epoxy-1,6,9-triene, 6,7-epoxy-1,3,9-triene, and 9,10-epoxy-1,3,6-triene), which were separable by LC as well as GC. Detailed inspection of the mass spectra of the C(19)-C(21) epoxides indicated the following diagnostic ions for determining the chemical structures: m/z 79, M-70, and M-41 for the 3,4-epoxytrienes; m/z 79, 95, 109, and 149 for the 6,7-epoxytrienes; and m/z 79, 106, 120, M-121, and M-107 for the 9,10-epoxytrienes. Resolution of two enantiomers of each C(21) epoxytriene was accomplished by HPLC equipped with a chiral column, and analysis of the pheromone extracted from virgin females of H. cunea revealed the 9S,10R configuration of the natural epoxytriene as the same configuration of C(21) 9,10-epoxydiene, a main pheromone component of this species. GC-EAD analysis of the optically pure epoxides showed that the antennae of male H. cunea were stimulated more strongly (>100 times) by the (9S,10R)-isomers than the antipodes.


Asunto(s)
Compuestos Epoxi/química , Mariposas Nocturnas/metabolismo , Polienos/química , Atractivos Sexuales/química , Animales , Conducta Animal/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Femenino , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Masculino , Mariposas Nocturnas/efectos de los fármacos , Polienos/farmacología , Atractivos Sexuales/farmacología , Estereoisomerismo
7.
Biosci Biotechnol Biochem ; 76(11): 2153-5, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23132583

RESUMEN

Larvae of the clearwing moth, Carmenta mimosa (Lepidoptera: Sesiidae), bore into the trunk of Mimosa pigra L., which is one of the most invasive weeds in Vietnam. GC-EAD and GC-MS analyses of a pheromone gland extract revealed that the female moths produced (3Z,13Z)-3,13-octadecadienyl acetate. A lure baited with the synthetic acetate alone successfully attracted C. mimosa males in a field test. While the addition of a small amount of the corresponding alcohol did not strongly diminish the number of captured males, a trace of the aldehyde derivative or the (3E,13Z)-isomer markedly inhibited the attractiveness of the acetate. The diurnal males were mainly attracted from 6:00 am to 12:00 am.


Asunto(s)
Lepidópteros/efectos de los fármacos , Lepidópteros/metabolismo , Control Biológico de Vectores/métodos , Malezas , Atractivos Sexuales/metabolismo , Atractivos Sexuales/farmacología , Control de Malezas/métodos , Animales , Femenino , Masculino , Mimosa , Conducta Sexual Animal/efectos de los fármacos , Vietnam
8.
Mov Disord ; 26(6): 1142-8, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21626558

RESUMEN

This review examines some of the advances in understanding myoclonus over the last 25 years. The classification of myoclonus into cortical, brainstem, and spinal forms has been consolidated, each with distinctive clinical characteristics and physiological mechanisms. New genetic causes of myoclonus have been identified, and the molecular basis of several of these conditions has been discovered. It is increasingly apparent that disease of the cerebellum is particularly important in the genesis of cortical reflex myoclonus. However, the precise mechanism and origin of myoclonus in many situations remain uncertain. Effective treatment of myoclonus remains limited, and the challenge lies ahead to develop more therapeutic options.


Asunto(s)
Mioclonía , Animales , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Mioclonía/historia , Mioclonía/patología , Mioclonía/terapia
9.
Mov Disord ; 26(8): 1509-14, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21506164

RESUMEN

The clinical implications of enlarged early cortical components of somatosensory evoked potentials in benign adult familial myoclonus epilepsy remain unknown. Somatosensory evoked potentials following electrical stimulation of the median nerve at the wrist were studied in 16 patients with a clinical diagnosis of benign adult familial myoclonus epilepsy (7 men and 9 women; mean age, 51 ± 18 years) and 19 age-matched apparently healthy control subjects (11 men and 8 women; mean age, 49 ± 18 years). Giant somatosensory evoked potentials were observed in 13 of the 16 patients. P25 and N35 amplitudes in the patient group were 11.4 ± 6.1 and 19.2 ± 11.5 µV, respectively, and both were significantly larger compared with those in control subjects (P = 0.008 for P25 and P < 0.0001 for N35). There was a significant positive relationship between age at somatosensory evoked potential examination and N20, P25, and N35 amplitudes, both in the patient and in the control groups (P < 0.05). The linear regression gradient of the N35 amplitude with respect to age was significantly larger in the patient group than in the control group (P = 0.04). Furthermore, regression analysis showed a significant positive relationship between the myoclonus rating scale and age at time of somatosensory evoked potential examination (R = 0.645, P = 0.007). Somatosensory evoked potential amplitude increased with age in patients with benign adult familial myoclonus epilepsy to a greater extent than in the control subjects, which suggests a progressive increase in cortical excitability based on progressive pathophysiology in benign adult familial myoclonus epilepsy.


Asunto(s)
Envejecimiento , Epilepsias Mioclónicas/patología , Epilepsias Mioclónicas/fisiopatología , Potenciales Evocados Somatosensoriales/fisiología , Mioclonía/fisiopatología , Corteza Somatosensorial/fisiopatología , Adulto , Anciano , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Reacción , Índice de Severidad de la Enfermedad
10.
Rinsho Shinkeigaku ; 61(11): 762-764, 2021 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-34657924

RESUMEN

A 79-year-old woman presented 3 years' history of hand shaking while drinking a cup of tea. The tremor was seen bilaterally, more predominantly on the left, and it also appeared when reading a book or writing. It was also induced by flexing the elbow to about 90 degrees or more without any specific task. Although there was no family history, the tremor in the present case was clinically diagnosed as essential tremor, because there were no other movement abnormalities, and other causes of tremor were excluded by laboratory tests. The tremor was dependent on the position of the involved extremity regardless of the kind of tasks. Position-specific tremor is discussed in relation to postural tremor.


Asunto(s)
Trastornos del Movimiento , Temblor , Anciano , Extremidades , Femenino , Humanos , Temblor/diagnóstico , Temblor/etiología
11.
Clin Neurophysiol ; 132(10): 2608-2638, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34488012

RESUMEN

Clinical neurophysiology studies can contribute important information about the physiology of human movement and the pathophysiology and diagnosis of different movement disorders. Some techniques can be accomplished in a routine clinical neurophysiology laboratory and others require some special equipment. This review, initiating a series of articles on this topic, focuses on the methods and techniques. The methods reviewed include EMG, EEG, MEG, evoked potentials, coherence, accelerometry, posturography (balance), gait, and sleep studies. Functional MRI (fMRI) is also reviewed as a physiological method that can be used independently or together with other methods. A few applications to patients with movement disorders are discussed as examples, but the detailed applications will be the subject of other articles.


Asunto(s)
Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Trastornos del Movimiento/diagnóstico por imagen , Trastornos del Movimiento/fisiopatología , Movimiento/fisiología , Neuroimagen/normas , Mapeo Encefálico/métodos , Mapeo Encefálico/normas , Electroencefalografía/métodos , Electroencefalografía/normas , Electromiografía/métodos , Electromiografía/normas , Análisis de la Marcha/métodos , Análisis de la Marcha/normas , Humanos , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/normas , Magnetoencefalografía/métodos , Magnetoencefalografía/normas , Neuroimagen/métodos
12.
Rinsho Shinkeigaku ; 50(10): 710-3, 2010 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-21061550

RESUMEN

A 73-year-old Japanese male was admitted because of difficulty in standing up after acute upper respiratory inflammation with mild fever followed by watery diarrhea. Neurological examination revealed moderate proximal muscle weakness and loss of tendon reflexes in all extremities. The blood sodium level was 106 mEq/l on admission. The blood level of antidiuretic hormone (ADH), renin and aldsterone was 11.3 pg/ml (normal value 0.3-4.2), 0.2 ng/ml/h (0.2-2.7) and less than 10.0 pg/ml (38.9-307.0), respectively. The plasma osmolarity was 221 mOsm/kg (270-295), and the urine osmolarity was 416 mOsm/kg (50-1400). EMG and nerve conduction studies suggested acute demyelination in the motor and sensory nerves. CSF revealed 10 cells/mm3 and elevated protein to 98 mg/dl. The clinical course, laboratory data and electrophysiological findings suggested coexistence of the syndrome of inappropriate secretion of ADH (SIADH) and Guillain-Barré syndrome (GBS) from the very early clinical stage of the diseases. The clinical and laboratory findings improved after intravenous administration of saline over three weeks. When GBS is associated with SIADH, hyponatremia is commonly seen at the peak of motor paralysis, often accompanied by autonomic or respiratory failure requiring mechanical ventilation. This was not the case in the present patient. It is postulated that SIADH, like GBS, might be caused by an autoimmune mechanism.


Asunto(s)
Síndrome de Guillain-Barré/complicaciones , Síndrome de Secreción Inadecuada de ADH/complicaciones , Anciano , Humanos , Masculino
13.
Epilepsia ; 50(9): 2072-84, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19453721

RESUMEN

PURPOSE: Seizure manifesting motor arrest, that is, negative motor seizure (NMS), is a rare epileptic condition in which only inability to conduct voluntary movements or praxis is produced, although consciousness is preserved. The negative motor area (NMA) seems to be responsible, but its generator mechanism has not yet been clarified. PATIENTS AND METHODS: Three patients manifesting NMS were investigated. Two patients (ages 33 and 17) with intractable frontal lobe epilepsy had subdural grid implantation for epilepsy surgery, and one (age 77) had scalp electroencephalography (EEG) monitoring. RESULTS: Ictal semiologies commonly observed, at least in the two patients, were found as follows; (1) indescribable or ill-localized aura, (2) repetitive involuntary vocalization, (3) inability to speak, (4) inability to move the extremities, and (5) subsequent evolution to positive motor seizures. Awareness and comprehension were preserved throughout the episode before generalized seizures. In two patients with epicortical EEG recording, ictal activity arose from the lateral NMA in one, and from the rostral supplementary motor area in the other. Cortical stimulation at NMA in one patient elicited symptoms identical to NMS. Another patient had scalp EEG and magnetic resonance imaging (MRI) abnormality, both suggesting the epileptogenic focus in the mesial frontal area. CONCLUSION: We showed that (1) NMS was a rare condition in patients with seizure focus in the frontal lobe, and (2) that the NMA was responsible for the symptoms. The documented state in the present study may reflect ictal apraxia, but it requires further investigation.


Asunto(s)
Epilepsia del Lóbulo Frontal/diagnóstico , Corteza Motora/cirugía , Convulsiones/diagnóstico , Adolescente , Adulto , Anciano , Apraxias/diagnóstico , Apraxias/cirugía , Electroencefalografía , Epilepsia/diagnóstico , Epilepsia del Lóbulo Frontal/cirugía , Lateralidad Funcional/fisiología , Humanos , Imagen por Resonancia Magnética , Trastornos del Movimiento/diagnóstico , Trastornos del Movimiento/cirugía , Mutismo/diagnóstico , Mutismo/cirugía , Convulsiones/cirugía , Trastornos del Habla/diagnóstico , Trastornos del Habla/cirugía
14.
Epileptic Disord ; 11(2): 126-31, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19477714

RESUMEN

We report the case of a 32-year-old patient who presented with catatonic stupor during the course of acute aseptic encephalitis involving the right frontotemporal area. Flumazenil-PET performed during the stupor indicated decreased benzodiazepine receptor binding in the right frontotemporal area where glucose metabolism was preserved as revealed by FDG-PET. An injection of diazepam immediately ameliorated catatonic symptoms and reduced widespread high amplitude slow EEG activities with right frontotemporal predominance. Compared with a SPECT study performed a week earlier, there was no abnormal right-sided anteriorly predominant cerebral hyperperfusion after injection of diazepam. While neither flumazenil- nor FDG-PET could be repeated, and with the caveat that generalized convulsions occurred initially and epilepsia partialis continua was present for two weeks starting on the 23rd day after illness onset, these findings suggest that in our case the presentation with catatonic stupor may be related to impairment of the cortical GABAergic inhibitory system.


Asunto(s)
Catatonia/tratamiento farmacológico , Catatonia/metabolismo , Corteza Cerebral/metabolismo , Corteza Cerebral/fisiopatología , Diazepam/farmacología , Moduladores del GABA/farmacología , Tomografía de Emisión de Positrones , Enfermedad Aguda , Adulto , Catatonia/etiología , Diazepam/administración & dosificación , Electroencefalografía , Encefalitis/complicaciones , Flumazenil/metabolismo , Fluorodesoxiglucosa F18 , Lóbulo Frontal/metabolismo , Lóbulo Frontal/fisiopatología , Lateralidad Funcional , Moduladores del GABA/administración & dosificación , Glucosa/metabolismo , Humanos , Masculino , Radiofármacos , Estupor/etiología , Estupor/metabolismo , Lóbulo Temporal/metabolismo , Lóbulo Temporal/fisiopatología , Tomografía Computarizada de Emisión de Fotón Único
16.
Clin Neurophysiol ; 119(4): 731-43, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18187361

RESUMEN

In view of the recent advance in functional neuroimaging, the current status of non-invasive techniques applied for human brain mapping was reviewed by integrating two principles: hemodynamic and electrophysiological, from the viewpoint of clinical neurophysiology. The currently available functional neuroimaging techniques based on hemodynamic principles are functional magnetic resonance imaging (fMRI), positron emission tomography (PET) or single-photon emission computed tomography (SPECT), and near-infrared spectroscopy (NIRS). Electrophysiological techniques include electroencephalography (EEG), magnetoencephalography (MEG), and transcranial magnetic stimulation (TMS). As for the coupling between hemodynamic response and neuronal activity (neurovascular coupling), experimental studies suggest that the hemodynamic response is significantly correlated to neuronal activity, especially local field potential (synaptic activity) rather than spiking activity, within a certain range. The hemodynamic response tends to be more widespread in space and lasts longer in time as compared with the neuronal activity. Since each technique has its own characteristic features especially in terms of spatial and temporal resolution, it is important to adopt the most appropriate technique for solving each specific question, and it is useful to combine two techniques either simultaneously or in separate sessions. As for the multi-modal approach, the combined use of EEG and MEG, EEG and PET, or EEG and fMRI is applied for the simultaneous studies, and for the separate use of two different techniques, the information obtained from fMRI is used for estimating the generator source from EEG or MEG data (fMRI-constrained source estimation). Functional connectivity among different brain areas can be studied by using a single technique such as the EEG coherence or the correlation analysis of fMRI or PET data, or by combining the stimulation technique such as TMS with neuroimaging. Further advance of each technology and improvement in the analysis method will promote the understanding of precise functional specialization and inter-areal coupling, and will contribute to the increased efficacy of rapidly developing physiological treatments of neurological and psychiatric disorders.


Asunto(s)
Mapeo Encefálico , Electrofisiología , Hemodinámica , Encéfalo/irrigación sanguínea , Mapeo Encefálico/métodos , Circulación Cerebrovascular/fisiología , Electroencefalografía , Electrofisiología/métodos , Humanos , Imagen por Resonancia Magnética , Magnetoencefalografía , Tomografía de Emisión de Positrones , Tomografía Computarizada de Emisión de Fotón Único , Estimulación Magnética Transcraneal
17.
Neurosci Lett ; 433(2): 87-92, 2008 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-18249498

RESUMEN

We sought to determine whether coherent networks which circumvent lesioned cortex are seen in patients with ideomotor apraxia (IMA) while performing tool-use pantomimes. Five normal subjects and five patients with IMA (three patients with corticobasal degeneration and two with left hemisphere stroke) underwent 64-channel EEG recording while performing three tool-use pantomimes with their left hand in a self-paced manner. Beta band (20-22 Hz) coherence indicates that normal subjects have a dominant left hemisphere network responsible for praxis preparation, which was absent in patients. Corticobasal degeneration patients showed significant coherence increase between left parietal-right premotor areas. Left hemisphere stroke patients showed significant coherence increases in a right parietofrontal network. The right hemisphere appears to store useable praxis representations in IMA patients with left hemisphere damage.


Asunto(s)
Apraxia Ideomotora/patología , Apraxia Ideomotora/fisiopatología , Corteza Cerebral/fisiopatología , Electroencefalografía , Red Nerviosa/fisiopatología , Adulto , Anciano , Lateralidad Funcional/fisiología , Humanos , Persona de Mediana Edad , Enfermedades Neurodegenerativas/patología , Enfermedades Neurodegenerativas/fisiopatología , Accidente Cerebrovascular/patología , Accidente Cerebrovascular/fisiopatología
18.
Brain ; 130(Pt 1): 181-97, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17046857

RESUMEN

In order to understand the complex functional organization of the motor system, it is essential to know the anatomical and functional connectivity among individual motor areas. Clinically, knowledge of these cortico-cortical connections is important to understand the rapid spread of epileptic discharges through the network underlying ictal motor manifestation. In humans, however, knowledge of neuronal in vivo connectivity has been limited. We recently reported a new method, 'cortico-cortical evoked potential (CCEP)', to electrically track the cortico-cortical connections by stimulating a part of the brain through subdural electrodes and recording the cortical evoked potentials that emanate from a distant region of the cortex via neuronal projections. We applied the CCEP methodology to investigate in vivo cortico-cortical connections between the lateral motor cortex [LMCx; sensorimotor (SM) and lateral premotor areas] and the medial motor cortex [MMCx; supplementary motor area proper (SMA), pre-SMA and foot SM]. Seven patients with intractable partial epilepsy were studied. These patients had chronic implantation of subdural electrodes covering part of the lateral and medial frontal areas. As a part of the routine pre-surgical evaluation, comprehensive cortical mapping was performed by electrical stimulation of the subdural electrodes, and the precise localization of the subdural electrodes was defined by MRI co-registration. Single-pulse electrical stimuli were delivered to MMCx (7 patients) and LMCx (4), and CCEPs time-locked to the stimuli were recorded by averaging electrocorticograms from LMCx and MMCx, respectively. Short-latency CCEPs were observed when stimulating MMCx and recording from LMCx (mean latency: 21.6 ms, range: 9-47 ms) and vice versa when stimulating LMCx and recording from MMCx (mean latency: 29.4 ms, range: 11-57 ms). In terms of the location of these stimulus sites and CCEP responses along the rostrocaudal axis, regression analysis revealed a consistent correlation between the sites of stimulation and maximum CCEP for stimulation of both MMCx and LMCx. Functionally, stimulation of the positive motor areas in MMCx elicited CCEPs at the somatotopically homologous regions in LMCx (71%). The same findings were observed in MMCx (82%) upon stimulation of LMCx. In four subjects in whom bi-directional connectivity was investigated by stimulating both MMCx and LMCx, reciprocality was observed in the majority of connections (78-94%). In conclusion, the present study demonstrated a human motor cortico-cortical network connecting (i) anatomically homologous areas of LMCx and MMCx along the rostrocaudal cognitive-motor gradient; and (ii) somatotopically homologous regions in LMCx and MMCx in a reciprocal manner.


Asunto(s)
Epilepsia Parcial Motora/fisiopatología , Potenciales Evocados Motores/fisiología , Corteza Motora/fisiopatología , Adolescente , Adulto , Mapeo Encefálico/métodos , Enfermedad Crónica , Estimulación Eléctrica/métodos , Electrodos , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Red Nerviosa/fisiopatología , Vías Nerviosas/fisiopatología , Tiempo de Reacción
19.
Rinsho Shinkeigaku ; 48(7): 501-4, 2008 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-18717185

RESUMEN

A 39-year-old man acutely developed diplopia, vertigo, unsteady gait, and disturbance of consciousness following an upper respiratory infection. Neurological examination showed ophthalmoplegia, facial paralysis, tetraplegia and loss of deep tendon reflexes. Babinski reflex was positive on the left and there were bilateral flexor withdrawal reflexes. He also developed ballism-like involuntary movements in all extremities, loss of proprioception predominantly on the left, and severe truncal ataxia. Anti-GQ1b IgG antibody was selectively elevated in serum, and CSF protein was elevated to 53 mg/dl with cell count of 12/mm3. Nerve conduction study showed decreased amplitude of compound motor action potentials in all extremities, and no response in facial muscles. Cranial MRI showed no abnormalities whereas EEG was severely abnormal with lack of posterior dominant rhythm and the presence of continuous diffuse theta-waves. This case presented clinical characteristics of three syndromes concurrently-Fisher syndrome, Bickerstaff brainstem encephalitis, and Guillain-Barré syndrome-that may be collectively called 'anti-GQ1b IgG antibody syndrome'. The unique feature of the present case was development of deep coma and ballism-like movements, associated with selective increase of serum anti-GQ1b IgG antibody. It is thus conceivable that anti-GQ1b IgG antibody might underlie the pathogenesis of all three conditions.


Asunto(s)
Tronco Encefálico , Encefalitis/complicaciones , Síndrome de Guillain-Barré/complicaciones , Síndrome de Guillain-Barré/terapia , Inmunoglobulinas Intravenosas/uso terapéutico , Síndrome de Miller Fisher/complicaciones , Adulto , Discinesias/etiología , Gangliósidos/inmunología , Humanos , Masculino
20.
Clin Neurophysiol Pract ; 3: 6-10, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30214999

RESUMEN

OBJECTIVE: Patients with motor neuron disease rarely present with fasciculation which is large enough to be clinically recognized as myoclonus. This study is aimed at elucidating the features of large fasciculation manifesting as myoclonus by using surface electromyography (surface EMG) and dynamic echomyography (dynamic Echo). METHODS: Four patients with amyotrophic lateral sclerosis, two of whom clinically presented with both fasciculation and myoclonus, were studied by using the surface EMG and the dynamic Echo. RESULTS: At rest, all patients had fasciculation in atrophic muscles, and the surface EMG showed occasional discharges of different waveforms corresponding to fasciculation. During voluntary gentle muscle contraction, the surface EMG showed repetitive discharges in the contracting muscle, which were constant in size and waveform within each muscle. The muscle Echo at rest revealed occasional contractions of a small number of muscle fibers corresponding to fasciculation. During voluntary muscle contraction, the number of muscle fibers involved in the involuntary motor phenomena was larger in the patients who clinically presented with myoclonus compared with other patients who clinically presented only with fasciculation. In a patient who presented with myoclonus, there was no contraction in the antagonist muscle. CONCLUSIONS: Fasciculation involving a large number of muscle fibers clinically manifests as spinal myoclonus. SIGNIFICANCE: Fasciculation involving a large number of muscle fibers can be a cause of spinal myoclonus.

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