We serendipitously found that zonisamide (ZNS) , an antiepileptic agent, has beneficial effects on Parkinson disease. A 25mg once a day of ZNS (200-600mg/day for epilepsy) , significantly improves motor function of advanced patients with Parkinson disease. Its effects maintained at least one year even in patients with advanced stage.
It was finally approved as an anti parkinsonian agent in Japan on January 2009. As the mechanism of antiparkinsonian effects of ZNS, we showed that ZNS increases dopamine contents in the striatum by activating dopamine synthesis through increasing the levels of tyrosine hydroxylase (TH) mRNA and TH protein. It moderately inhibits monoamine oxydase (MAO) activity. ZNS shows significant inhibition on T-type Ca⁺⁺channel. It may also affect the beneficial effects of ZNS on Parkinson disease. ZNS also showed neuroprotective effects on several parkinsonian models. It markedly inhibited quinoprotein formation and increased the level of glutathione by enhancing the astroglial cystine transport system and/or astroglial proliferation through S100β. We will verify the neuroprotective effects of ZNS on patients with Parkinson disease and study the factors responsible for the individual difference of the effects of ZNS by using genome wide association study (GWAS) in the near feature.

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In an attempt to understand the fundamental mechanism for movement disturbances in Parkinson's disease (PD) patients, we investigated their straightforward or right diagonally (laterally) steps and step over a stick.
In all tasks, in PD patients, the movement latency was significantly longer and the movement duration was significantly shorter than those of the controls. In the lateral step task, the maximum velocity of PD subjects was significantly faster than that of the controls, while the reaching time to maximum velocity was longer. Moreover, in the task to step over a stick, the reaching time to maximum velocity was significantly longer than that of the controls. In the velocity profiles, in PD patients, the deceleration after the maximum acceleration was rapider than that of the controls. In addition, the PD patients' jerk was significantly larger than that of the controls. These results suggest that PD patients have deficits in motor programming and motor control which may be due to dysfunction of the cortico-basal ganglia loop.

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We reported the two cases with bulbar-onset ALS showing isolated agraphia without overt dementia and aphasia. Patients 1 was a 69-year old man and patient 2 was an 81-year-old woman, and both were right-handed. Each patient developed dysarthria as an initial symptom followed by dysphagia, and neurological examinations showed atrophy and fasciculation of the tongue with upper and lower motor-neuron involvement of the extremities. These characteristic features with electromyographic evidence including widespread acute and chronic denervation led to a diagnosis of bulbar-onset ALS. Around 1 year after the onset of ALS, dysarthria was mild enough to allow oral communication enabling the determination that aphasia was absent with well preserved confrontation naming, repetition, reading and comprehension. The patients were polite without abnormal behavior or character change, and their general intelligence was also well preserved with excellent scores on the Mini Mental State Examination (30 and 27 points for patients 1 and 2, respectively) and Frontal Assessment Battery (16 points for each patient) . However, spontaneous writing and dictation revealed abundant writing errors characterized by omission of kana letters and paragraphia of kana and kanji letters in both patients. Some syntactic errors were also observed in writing but in spoken language. A letter-number effect on writing errors was observed in patient 1. Copying of letters or words was intact and structure and orientation of written letters was well preserved, indicating the absence of constructional, apraxic or spatial feature of agraphia. Single photon emission computed tomography demonstrated reduced uptake in the bilateral frontotemporal lobes, predominantly in the left hemisphere, with less evident alternation in magnetic resonance imaging. Our results suggest that patients with bulbar-onset ALS may develop isolated agraphia as a single-domain cognitive impairment, preceding the clinical manifestation of aphasia or dementia. We speculate that the main responsible region might be the posterior part of the middle and inferior frontal gyri including Exner's writing center and Broca's area beyond the primary motor cortex.

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A 47-year-old man with a diagnosis of paranasal Wegener's granulomatosis was admitted to our hospital for generalized seizures. He had been treated with long-term predonine therapy after the initial onset of Wegener's granulomatosis. The ictal EEG showed generalized spike and wave complexes, mainly presenting in the bifrontal areas. The postictal EEG revealed periodic localized sharp discharges in the left frontal area. At the initial seizure onset, a midline multilobular mass lesion having a heterogeneous enhancement effect was detected in the lower frontal lobe on gadolinium-enhanced T₁-weighted imaging (Gd T₁-WI) . The anterior skull base and bifrontal lobes were encroached by upward contiguous invasion of the midline mass lesion from the ethmoid sinus on Gd T₁-WI. The high signal intensity lesions in the bifrontal lobes on T₂- and Gd T₁-WI resolved with palliative predonine therapy following methylpredonisolone pulse therapy. Recurrent generalized tonic-clonic status epilepticus was caused by the granulomatous lesion encroaching on the frontal lobe with contiguous invasion from the paranasal Wegener's granulomatosis.

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We reported a patient with immune-mediated encephalopathy showing refractory epilepsy and multiple brain lesions on MRI. The patient had high titers of anti-glutamic acid decarboxylase (GAD) antibody in sera and cerebrospinal fluid (CSF) . A 36-year-old previously healthy woman was admitted to our hospital with onset of sudden generalized seizure that then persisted for one month. She had repeated epileptic attacks accompanied with loss of consciousness, and was refractory to valproic acid, zonisamide (200mg/day) and phenobarbital (200mg/day) . Brain MRI showed multiple hyperintense lesions in predominantly bilateral frontal lobes, parietal lobes, occipital lobes and cingulate cortices. EEG showed epileptic activities (frequent sharp waves) in bilateral frontal regions. After admission, attacks disappeared through the administration of clonazepam (1.5mg/day) , though the patient remained slightly disoriented. As titers of anti-GAD antibody in sera and CSF were extremely high, we implemented plasma exchanges. After treatment, titers of anti-GAD antibody in sera and CSF decreased. The patient completely recovered to an alert state and the abnormal MRI lesions almost disappeared.
Since GAD catalyzes production of γ-aminobutyric acid (GABA) , it is proposed that anti-GAD antibodies reduce synthesis of GABA or interferes with exocytosis of GABA in the nervous system. Anti-GAD antibodies are detected in some rare neurological disorders such as stiff-person syndrome. Recently, anti-GAD antibodies have been reported as implicated in cerebellar ataxia, palatal myoclonus, refractory epilepsy and limbic encephalitis. Epilepsy associated with the anti-GAD antibody is mostly pharmacoresistant temporal lobe epilepsy; with brain MRI showing no abnormality or only hippocampal sclerosis. It is very rare that brain MRI shows extensive abnormal lesions except in the hippocampus. This case suggests that anti-GAD antibodies could contribute to unexplained encephalopathy with extensive brain MRI lesions and drug-resistant symptomatic epilepsy.

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A 28-year-old man had experienced non-progressive gait disturbance since early childhood. He was admitted because of hypogonadism and cerebellar ataxia. On admission, bilateral vitelliform macular dystrophy, fixation nystagmus, slurred speech, cerebellar ataxia, decreased tendon reflexes, and pes cavus were present. Higher brain function, auditory function, and olfactory function were not disturbed. A gene abnormality related to known hereditary spinocerebellar degeneration and Kallman syndrome was not observed. Brain MRI demonstrated cerebellar atrophy. ECD-SPECT revealed decreased blood flow in the brain stem and cerebellum. Endocrinological tests indicated that the hypogonadism seemed to be due to a primary pituitary disturbance. This is the second case of Boucher-Neuhäuser syndrome in Japan.

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A 19-year-old female in her 2^nd trimester (17 weeks) of pregnancy became irritable a few days before admission. She became unable to open her mouth and could not talk. She was admitted to the psychiatric hospital due to a rapid change in behavior and a consciousness disturbance. She was diagnosed as having schizophrenia by a psychiatrist. Her EEG showed diffuse high voltage and slow waves. Acute encephalitis was then suspected. Her past and family histories were not suggestive of viral infection. On physical examination, she had a low grade fever. She had hyperhidrosis, autophagia, and repeated oral dyskinesia. Her consciousness level fluctuated from somnolence to stupor. Although her blood CRP level was mildly elevated and she had mild pleocytosis, HSV-PCR was negative in the cerebrospinal fluid (CSF) . Abdominal ultrasound examination and MRI showed no ovarian teratoma. Computed tomography (CT) and magnetic resonance imaging (MRI) showed no brain abnormalities.
Before analysis for specific nervous system antibodies, the initial diagnosis was non-herpetic limbic encephalitis. She was twice treated with a 6-day course of methylprednisolone (500mg/day) infusion. She was also given phenobarbital since she had a tonic-clonic seizure about 1 month after admission. Finally, she had a normal delivery at 37 weeks. The baby was healthy, and the patient was discharged without sequelae.
We concluded that her diagnosis was anti-N-methyl-D-aspartate (NMDA) receptor (anti-NMDAR) encephalitis based on the presence of anti-NMDAR antibody in the CSF.
This report is the first description of a patient with anti-NMDAR antibody encephalitis. The precise mechanism of this encephalitis is not clear, although there have been several reports of autoimmune encephalitis during pregnancy. The patient's CSF anti-NMDAR antibody titer during treatment was measured. Before treatment, the CSF anti-NMDAR antibody titer was strongly positive, but it decreased during treatment and then disappeared after delivery. We hypothesized that the presence of the embryo or placenta may have triggered an antigenic signal and/or antibody through inappropriate immunological modulation.

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We report a patient with superficial siderosis that repeated episodes of epilepsy. The patient was a 62 year old male, and underwent an operation for the tumor of the spinal cord at 22 years of age. He had become deaf at 50 years of age, and repeated loss of consciousness at 59 years of age and later. Neurological examination revealed cerebellar ataxia and bilateral sensorineural deafness in addition to paraplegia, which was caused by the spinal cord tumor. Brain MRI showed low intensity rim around the brain stem, cerebellar hemisphere, and inferior aspects of the temporal and frontal lobes, being consistent with superficial siderosis. Hemosiderin deposition for an extended period was considered to contribute to the pathogenesis of epilepsy.

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We report the case of a 60-year-old woman with myasthenia gravis (MG) and Basedow's disease who seven years after thymectomy developed subacute myelitis, a limited form of neuromyelitis optica (NMO) . The patient presented with a centrally located long spinal cord lesion (LCL) on cervical cord MRI, anti-aquaporin 4 (AQP4) antibody in serum, and HLA DPB1^*0501. Brain MRI showed no specific findings of classic multiple sclerosis (MS) . CSF study showed elevated protein (67mg/dl) but a normal IgG index (0.63) and no oligoclonal IgG bands. After repeated methylprednisolone pulse and immunoadsorption therapies, the T₂-high signal lesion shrunk and tetraparesis improved.
We reviewed the English and Japanese literature and found reports of 30 patients showing MS including NMO complicated with MG; 27 had been diagnosed as MS after thymectomy. Among these 27, 16 of 17 who were examined by spinal cord MRI and for anti-AQP4 antibodies were NMO. Only one patient with signs and symptoms localized to the optic nerves and spinal cord showed no LCL and was not examined for anti-AQP4 antibodies. In autoimmune disorders of the central nervous system after thymectomy in patients with MG, NMO is more predominant than classic MS.

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