Ekini Nakai

Ablation of the subthalamic nucleus supports the survival of nigral dopaminergic neurons after nigrostriatal lesions induced by the mitochondrial toxin 3-nitropropionic acid

We investigated the role of the excitatory afferents from the subthalamic nucleus (STN) in the death of nigral dopamine (DA) neurons after nigrostriatal axon terminal lesions. Nigral DA neurons were detected by use of both tyrosine hydroxylase immunolabeling or retrograde labeling of nigral cells with fluorogold. Sprague–Dawley rats were subjected to unilateral, quinolinic acid–induced destruction of the STN. Sham lesions of the STN were made by injecting phosphate‐buffered saline. Two weeks after STN ablation, lesions of nigrostriatal DA neurons were induced by intrastriatal injections of either the mitochondrial toxin 3‐nitropropionic acid (3‐NP) or the catecholamine toxin 6‐hydroxydopamine (6‐OHDA). Intrastriatal injections of 3‐NP or 6‐OHDA caused a progressive loss of nigral tyrosine hydroxylase–positive or fluorogold‐labeled DA neurons in a dose‐dependent manner. Previous ablation of the STN significantly attenuates the loss of DA neurons in rats receiving 3‐NP but not 6‐OHDA. Sham lesions of the STN did not affect DA neuron death induced by the toxins. The results indicate that the excitatory inputs from the STN may contribute to the death of nigral DA neurons under a condition of 3‐NP–induced metabolic impairment. Ann Neurol 1999;45:640–651

Transplantation of Autologous Sympathetic Ganglion into the Brain with Parkinson's Disease

Transplantation of autologous sympathetic ganglion was performed in 35 patients with Parkinsons disease. Approximately half the patients showed improvement of parkinsonian symptoms over the 3 years following transplantation. The patients showed amelioration of bradykinesia and gait disturbance, but tremor and muscle rigidity were not improved by transplantation. The other half of the patients did not show amelioration after transplantation. No serious complications were encountered, though mild ptosis was observed in all patients. The mechanism of improvement of symptoms might be the release of dopamine from the grafted sympathetic ganglion. Transplantation of autologous sympathetic ganglion can be a therapeutic modality for Parkinsons disease.

Chronic encapsulated intracerebral hematoma during infancy: case report.

Chronic encapsulated intracerebral hematoma is a rare condition. Only four cases have been reported. The cause of this condition is unclear. A case of chronic encapsulated intracerebral hematoma in an 1-year-old infant is reported, and the characteristic findings and their causes are discussed with a literature survey.

Tuberous sclerosis with an atypical radiological skull change: case report.

The authors describe a case of tuberous sclerosis with atypical radiological skull change in a 8-year-old Japanese child. A plain roentgenogram showed thinning and convolution of the left occipital bone, and a cortical tuber adjacent to the thinned bone was shown by computed tomography. This kind of skull change may suggest the existence of a cortical tuber in patients with tuberous sclerosis, although this finding has not been reported previously. The mechanism of this skull change is discussed.

Stereotactic hyperthermia for brain tumors.

We have developed a localized hyperthermia system using computed tomography-stereotactic surgery as malignant brain tumor therapy. In an experimental study, the temperature in the area of the cat brain within 20 mm from a radiofrequency electrode reached more than 43.7 degrees C. Intravenous administration of MCNU during hyperthermia caused a significant increase of MCNU content in the heated brain as compared with a control brain. In the clinical study, localized radiofrequent hyperthermia using stereotactic surgery was performed on 7 malignant deep-seated gliomas and 21 metastatic brain tumors. Especially, combination therapy of stereotactic hyperthermia and chemotherapy was effective treatment for gliomas less than 30 mm deep in the brain.

Jargonagraphia with severe aphasia due to a right hemisphere lesion: case report.

The authors report a case of a patient who developed jargonagraphia, severe aphasia, unilateral spatial neglect and apraxia due to a right hemisphere lesion. Jargonagraphia with severe aphasia, unilateral spatial neglect and apraxia is quite rare. The mechanisms of jargonagraphia remain unknown. A possible mechanism underlying this case of jargonagraphia is discussed.

Stereotactic Evacuation of Hypertensive Intracerebral Hematoma Using Plasminogen Activator

Treatment of hypertensive intracerebral hemorrhage has generally been carried out using either surgical evacuation by craniotomy or by conservative therapy. In 1974, Komai et al. [9] demonstrated for the first time that intracerebral hematoma can be safely evacuated by stereotactic technique, and suggested that stereotactic evacuation may become an applicable surgical procedure for hypertensive intracerebral hematoma. In 1980, we reported, for the first time, an extensive series of intracerebral hematomas treated by stereotactic evacuation using a plasminogen activator [1]. This new surgical procedure has since been acknowledged by other authors to be a safe and valuable treatment method for hypertensive intracerebral hematoma [7]. Since 1978, we have treated 241 intracerebral hematomas using the stereotactic approach. We herein report an analysis of our series and offer discussion on several controversial points in the surgical treatment of this disease.

Transcortical sensory aphasia following the unilateral left thalamic infarction— A case report

Abstract We reported a 60-year old right handed woman who had transcortical sensory aphasia caused by left thalamic cerebral infarction. She had a mild right hemiparesis involving the face, with hyperactive tendon reflexes. Tactile and pain sensations were decreased in the right side involving the face without visual field defect. Spontaneous speech was remarkably reduced, and she had a remarkable disturbance in object naming. Her auditory comprehension and writing were severely disturbed. This contrasted with full preservation of repetition of words and short sentences (5

Chronic electrical stimulation of the globus pallidus for treatment of Parkinson's disease

6 words). A CT scan 3 days later showed an infarct in the left ventral region of the thalamus. In the CBF (cerebral blood flow) study, 123I-IMP SPECT (single photon emission CT) showed a low flow in the left temporal and occipital lobes. We concluded that there might be thalamic aphasia caused by an occlusion of the left posterior communicating artery directly affecting the area served by left posterior cerebral artery.

Sterotactic evacuation of pontine and cerebellar hemorrhages

Abstract We report the effect of pallidal stimulation for the patients with Parkinsons disease (PD) and the changes of neurotransmitters in the cerebrospinal fluid (CSF) during stimulation. Chronic pallidal stimulation was performed on 23 patients. Fourteen patients (60%) had an improvement in the H&Y scale and 16 patients (70%) showed more than 10% of improvement rate in the Unified Parkinsons Disease Rating Scale (UPDRS) score. Both showed statistic significance. The treatment was effective for tremor and rigidity, on the other hand, less effective for gait disturbance and bradykinesia. There were no serious complications or adverse effects. The concentration of Gamma-aminobutyric acid (GABA) in the CSF significantly increased during stimulation. In a few cases, an increase in the level of dopamine (DA), homovanillic acid (HVA) and noradrenaline (NA) was also seen. We conclude that pallidal stimulation has great effects in patients with PD, especially those who have tremor and/or rigidity as a chief symptom. The mechanism of the treatment would involve an activation of the GABAergic system in the globus pallidus.