In order to know the effects of caloric stimulation on neuronal firing in medial vestibular nuclei (MVN) by middle ear irrigation, the middle ear was irrigated with ice (4 degrees C), hot (44 degrees C), and warm (37 degrees C) water, and the firing rate of MVN neuron was extracellularly recorded. The results showed that the firing rate of MVN neuron was changed by caloric stimulation, and the majority of MVN neurons showed excitation by irrigation with hot water and inhibition by ice water (type A). The neuronal firing was recovered immediately after the cessation of the stimulation. I It was concluded that the neuronal firing rate in MVN was changed by caloric stimulation in middle ear cavity. The response was different in various neurons.
Cold ; Ear, Middle ; Electrophysiology ; Endolymph/physiology ; Heat ; Irrigation ; Neurons/classification ; Neurons/physiology ; Rats, Wistar ; Vestibular Nerve/*physiology ; Vestibular Nuclei/*physiology

Since the output of retina for visual stimulus is carried by neurons of very diverse functional properties, it is not adequate to use conventional single electrode for recording the retinal action potential. For this purpose, we used newly developed multichannel recording system for monitoring the simultaneous electrical activities of many neurons in a functioning piece of retina. Retinal action potentials are recorded with an extra-cellular planar array of 60 microelectrodes. In studying the collective activity of the ganglion cell population it is essential to recognize basic functional distinctions between individual neurons. Therefore, it is necessary to detect and to classify the action potential of each ganglion cell out of mixed signal. We programmed M-files with MATLAB for this sorting process. This processing is mandatory for further analysis, e.g. poststimulus time histogram (PSTH), auto-correlogram, and cross-correlogram. We established MATLAB based protocol for waveform classification and verified that this approach was effective as an initial spike sorting method.
Action Potentials ; Classification ; Electrodes ; Ganglion Cysts ; Microelectrodes ; Neurons ; Retina ; Retinal Ganglion Cells* ; Retinaldehyde*

Cortical dysplasia (CD) is considered to be a malformative lesion of the neocortex which exhibits a spectrum of pathologic changes reflecting a disturbance in the process of its development. CD is recently recognized as a major cause of intractable epilepsy with non-neoplastic lesions. Mischel et al. proposed that CD can be graded mild, moderate and severe with regard to nine specific microscopic abnormalities: mild CD consists of 1) cortical laminar disorganization, 2) single heterotopic white matter neurons, 3) neurons in the cortical molecular layer, 4) persistent remnants of the subpial granular cell layer, and 5) marginal glioneuronal heterotopia; moderate CD displays 6) polymicrogyria and 7) white matter neuronal heterotopia; severe CD phows 8) neuronal cytomegaly with associated cytoskeletal abnormalities and 9) balloon cell change. We reassessed 71 cases of cortical dysplasia to elucidate the proportion and histologic features of each group, using Mischel's grading system. CD was most frequently found in the temporal lobe with 50 cases (70%). Mild CD was predominently seen and was noted in 61 cases (86%) Cortical laminar disorganization and single heterotopic white matter neurons were identified in all mild CD cases. Neurons in the cortical molecular layer, persistent subpial granular cell layer, and marginal glioneuronal heterotopia were also noted in case numbers 40, 3, and 1 of mild CD, respectively. Moderate CD was composed of 2 cases with polymicrogyria, and the remaining 8 cases had severe CD. All moderate and severe CD were associated with the various histological features of mild CD. Thirty eight cases (51%) of CD showed dual pathology, composed of both CD and hippocampal sclerosis, and 5 cases of dysembryoplastic neuroepithelial tumor also had CD. Neurofilament immunostain revealed disarray of abnormally beaded axons in CD. We believe that the grading system of CD is very important to the evaluation and classification of CD.
Axons ; Classification ; Epilepsy ; Malformations of Cortical Development* ; Neocortex ; Neoplasms, Neuroepithelial ; Neurons ; Pathology ; Sclerosis ; Temporal Lobe

OBJECTIVE: Malignant gliomas with neuronal marker expression (MGwNM) are rare and poorly characterized. Increasingly diverse types of MGwNM have been described and these reported cases underscore the dilemmas in the classification and diagnosis of those tumors. The aim of this study is to provide additional insights into MGwNM and present the clinicopathological features of 18 patients. METHODS: We reviewed the medical records of 18 patients diagnosed as MGwNM at our institute between January 2006 and December 2012. Macroscopic total resection was performed in 11 patients (61%). We evaluated the methylation status of O6-methylguanine-DNA methyltransferase (MGMT) and expression of isocitrate dehydrogenase 1 (IDH-1) in all cases, and deletions of 1p and 19q in available cases. RESULTS: The estimated median overall survival was 21.2 months. The median progression-free survival was 6.3 months. Six patients (33%) had MGMT methylation but IDH1 mutation was found in only one patient (6%). Gene analysis for 1p19q performed in nine patients revealed no deletion in six, 19q deletion only in two, and 1p deletion only in one. The extent of resection was significantly correlated with progression free survival on both univariate analysis and multivariate analysis (p=0.002 and p=0.013, respectively). CONCLUSION: In this study, the overall survival of MGwNM was not superior to glioblastoma. The extent of resection has a significant prognostic impact on progression-free survival. Further studies of the prognostic factors related to chemo-radio therapy, similar to studies with glioblastoma, are mandatory to improve survival.
Classification ; Diagnosis ; Disease-Free Survival ; Glioblastoma ; Glioma* ; Humans ; Isocitrate Dehydrogenase ; Medical Records ; Methylation ; Multivariate Analysis ; Neurons*

Interneuron diversity is one of the key factors to hinder understanding the mechanism of cortical neural network functions even with their important roles. We characterized inhibitory interneurons in layer II/III of the rat primary visual cortex, using patch-clamp recording and confocal reconstruction, and classified inhibitory interneurons into fast spiking (FS), late spiking (LS), burst spiking (BS), and regular spiking non-pyramidal (RSNP) neurons according to their electrophysiological characteristics. Global parameters to identify inhibitory interneurons were resting membrane potential (> -70 mV) and action potential (AP) width (< 0.9 msec at half amplitude). FS could be differentiated from LS, based on smaller amplitude of the AP (< ~50 mV) and shorter peak-to-trough time (P-T time) of the afterhyperpolarization (< 4 msec). In addition to the shorter AP width, RSNP had the higher input resistance (> 200 M omega) and the shorter P-T time (< 20 msec) than those of regular spiking pyramidal neurons. Confocal reconstruction of recorded cells revealed characteristic morphology of each subtype of inhibitory interneurons. Thus, our results provide at least four subtypes of inhibitory interneurons in layer II/III of the rat primary visual cortex and a classification scheme of inhibitory interneurons.
Action Potentials ; Animals ; Classification* ; Interneurons* ; Membrane Potentials ; Neurons ; Rats* ; Visual Cortex*

We report the case of a 12 year old boy with a dysembryoplastic neuroepithelial tumor(DNT) of the left frontal lobe. Only recently recognized, this tumor is an uncommon neurosurgical lesion of adolescents and young adults, one with a benign clinical course and a long history of intractable partial complex seizures. DNT was first proposed by Daumas-Duport et al. and in the revised WHO histological classification, has recently been incorporated into the category of neuronal and mixed neuronal-glial tumors. Since the first description, there have been a few additional case reports of DNTs, including histological and radiological findings. Owing to the supratentorial and intracortical location of this tumor, and its association with cortical dysplasia, the onset of seizure is often early, either in childhood or adolescence. Unlike other dysgenetic lesions and some glial tumors, the prognosis after resection is thought-as far as seizure control is concerned-to be excellent. Identification of these neoplasms is of obvious therapeutic importance because it spares these young patients the deleterious long term effects of radio-or chemotherapy.
Adolescent ; Child ; Classification ; Drug Therapy ; Frontal Lobe ; Humans ; Male ; Malformations of Cortical Development ; Neoplasms, Neuroepithelial* ; Neurons ; Prognosis ; Seizures ; Young Adult

BACKGROUND: Neurocysticercosis (NCC) is the most common parasitic disease of the CNS and seizures are the most frequent clinical manifestations of it. Although the medical treatment of NCC is effective, epilepsy surgery is still needed to treat refractory seizures. We investigated five cases with refractory seizures due to NCC to verify perilesional epileptogenic changes in NCC. METHOD: We included 5 intractable epilepsy patients who had epilepsy surgery and pathologically proven cysticercosis although serological tests were negative. A routine EEG and brain MRI were performed in all patients. Video scalp-EEG monitorings were done in 5 patients, including an invasive-EEG monitoring in one. We analyzed the relationships between semiology, brain MRI, interictal, and ictal EEG findings, pathologic features and surgical outcomes. RESULTS: All patients had abdominal or psychic aura, evolving into automotor seizure and then secondarily generalized tonic clonic seizures. Two patients often had only the aura. In brain MRI, four patients had showed NCC lesions in the mesial temporal area, and one had it in the basal occipital area. Hippocampal atrophy was also detected in 3 patients. Irritative and ictal onset zones on an EEG were located around the lesions. Pathologic findings confirmed hippocampal sclerosis in 3 patients and coritcal dyslamination and many single heterotopic neurons in the temporal lobe in 1 patient. Surgical outcomes showed 3 patients in class IA, 1 in class IC, and 1 in class IIB by Engel classification. CONCLUSIONS: Epileptic foci could be formed focally around the NCC lesion and hippocampal sclerosis frequently accompanied when the lesion was located near the mesial temporal structures. After verifying epileptic foci and lesion, epilepsy surgery had good surgical outcome.
Atrophy ; Brain ; Classification ; Cysticercosis ; Electroencephalography ; Epilepsy* ; Humans ; Magnetic Resonance Imaging ; Neurocysticercosis* ; Neurons ; Parasitic Diseases ; Sclerosis ; Seizures ; Serologic Tests ; Temporal Lobe

Local spinal cord cooling and glucocorticoid administration have been shown to diminish the degree of traumatic hemorrhagic necrosis and improve spinal cord function after impact injury. Local cooling is said to influence multiple neural enzymatic processes diminish the cellular metabolic rate and lessen the oxygen requirements. Steroid is known to maintain vascular integrity after injury and protect cellular membrane in the state of poor perfusion. As a preliminary report, this experimental study demonstrated the sequence of pathologic changes occurring from hours to days after the spinal cord of a cat had been impacted by a 400gm-cm force respectively and, thereafter evaluated the effect of local cooling and steroid administration on the functional recovery of the spinal cord. Spinal injuries was produced by dropping a 20gm weight 20cm height through a vented guide tube to strike the exposed dura and cord. Animals were sacrificed hours or days after injury. The thoracic cord was removed to include the injured tissue adjacent cord for control. The specimens were taken for histological study and this was correlated with the clinical observation by Tarlov's classification. In the acute group (From 1 hour to 8 hours after injury), multiple hemorrhage and necrosis occurred in the central gray matter and periaxonal swelling in the white adjacent to gray matter. At 15 days all most gray matter was replaced by a large central cavity in which numerous lipid phagocytes were accumulated and disruption of white matter was severe in the adjacent to the cavity. The motor neurons were shown complete central chromatolysis in the all groups.
Animals ; Cats* ; Classification ; Hemorrhage ; Membranes ; Motor Neurons ; Necrosis ; Oxygen ; Perfusion ; Phagocytes ; Spinal Cord Injuries* ; Spinal Cord* ; Spinal Injuries ; Strikes, Employee

PURPOSE: Few studies have reported non-acute long-term morbidity rates in children with intestinal malrotation. The aim of this study was to investigate the rate of constipation in children undergoing Ladd's procedure for isolated intestinal malrotation. METHODS: This retrospective study included children aged <15 years who underwent Ladd’s procedure for intestinal malrotation between 2001 and 2016. Demographics, presence of volvulus perioperatively, need for bowel resection, short term (<30 days) and long-term complications, including mortality were recorded. Constipation was defined as treatment with laxatives at 1-year follow-up. RESULTS: Of the 43 children included in the study, 49% were boys. The median age at surgery was 28 days (0–5, 293 days). Volvulus occurred in 26 children (60.5%), and bowel resection was required in 4 children (9.3%). Short-term complications categorized as grades II–V according to the Clavien-Dindo classification occurred in 13 children (30.2%). Of these, 5 children (11.6%) required re-operation. Constipation was observed in 9 children (23.7%) at the 1-year follow-up. No difference was observed in the rate of perioperative volvulus between children with and without constipation (44% vs. 65%, p=0.45). Excluding re-operations performed within 30 days after surgery, 3 children (6%) underwent surgery for intestinal obstruction during the study period. CONCLUSION: Many children undergoing Ladd's procedure require bowel management even at long-term follow-up, probably secondary to constipation. It is important to thoroughly evaluate bowel function at the time of follow-up to verify or exclude constipation, and if treatment of constipation is unsuccessful, these children require evaluation for dysmotility disorders and/or intestinal neuronal dysplasia.
Child ; Classification ; Constipation ; Demography ; Follow-Up Studies ; Humans ; Intestinal Obstruction ; Intestinal Volvulus ; Laxatives ; Mortality ; Neurons ; Retrospective Studies

Achalasia is a rare esophageal motilty disorder characterized by loss of myenteric neurons leading to aperistalsis of the esophageal body and impaired relaxation of the lower esophageal sphincter (LES). Esophageal peristalsis and relaxation of the LES are mediated by myenteric neurons. Achalasia may be an autoimmune disease targeting esophageal myenteric neurons with cell-mediated and antibody-mediated attack to an unidentified antigen. It is still unknown how these immunologic attacks begin and why these are functionally limited to the esophagus. Initial immunologic reactions can begin in genetically predisposed persons who had viral infection, such as herpes simplex virus 1. The type of immune response and the intensity of the cytotoxic T-cell attack can determine the clinical presentation of the disease. Patients with Chicago Classification type III achalasia may present with chronic inflammation in the absence of neuronal loss, where as patients with Chicago Classification type I or II achalasia present with a predominantly cytotoxic immune response with progressive loss of myenteric neurons. Further well controlled researches which reveal the unknown facts of pathogenesis are needed.
Autoimmune Diseases ; Classification ; Esophageal Achalasia* ; Esophageal Sphincter, Lower ; Esophagus ; Herpesvirus 1, Human ; Humans ; Inflammation ; Myenteric Plexus ; Neurons ; Peristalsis ; Relaxation ; T-Lymphocytes