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T Itakura

Publications and source records attributed to T Itakura.

At least 109 records · Page 6Linked to original sources
PubMed1994

Regeneration of norepinephrine-containing fibers in occipital cortex of adult cats.

Regeneration of norepinephrine (NE)-containing nerve fibers in occipital cortex of adult cats was studied using morphological and biochemical methods. Initially, degeneration of cortical NE fibers was induced by direct infusion of 6-hydroxydopamine (6-OHDA) for a week. Cortical reinnervation by NE fibers continuously proceeded throughout 52 weeks, the longest survival period studied, after stopping 6-OHDA infusion. The rate of the reinnervation was slower in mature cortex than that obtained earlier in immature cortex. The present results indicate that the regenerative ability of the central NE neurons is universal, not limited to the immature brain. It is implied that the central NE neurons are equipped with a transmitter-specific repair mechanism throughout life.

Animals↗
PubMed1994

Unilateral spatial neglect due to right frontal lobe haematoma.

Two patients with unilateral spatial neglect caused by right frontal lobe lesions underwent cerebral blood flow studies. A 54-year-old, right-handed woman developed left hemiplegia and frontal lobe neglect associated with cerebral haemorrhage after surgical excision of a frontal tumour. A 66-year-old, right-handed woman developed a haemorrhage in the right frontal lobe caused by rupture of an aneurysm. This was followed by left hemiplegia and frontal lobe neglect. In both cases, 123I-iodoamphetamine single photon emission CT disclosed a reduction in regional cerebral blood flow localised along the circumference of the haematoma in the frontal lobe, but did not reveal any lesions in the parieto-occipital junction. These findings suggest that, in these two cases, the frontal lobe neglect was caused by lesions confined to the frontal lobe.

Cerebral Hemorrhage↗
PubMed1994

Autologous transplantation of the cervical sympathetic ganglion into the parkinsonian brain: case report.

The authors have reported a clinical trial of an autologous cervical sympathetic ganglion transplanted into the brain of a parkinsonian patient. A 45-year-old woman presented with bradykinesia and a gait disturbance for 8 years under L-dopa treatment. The patient underwent stereotactic transplantation of the right stellate ganglion into the right putamen. She showed marked amelioration of bradykinesia and gait disturbance 1 month after the operation, and she was able to conduct her activities of daily living without requiring L-dopa administration. The patient continued to improve gradually until 3 months after the operation. Two years after surgery, the patient functions independently as a housewife. The right hand tremor, however, became slightly worse after the operation, but it was transient. The patient developed a permanent right-sided Horner's syndrome after resection of the cervical sympathetic ganglion. Taken together with our previous data obtained from animal experiments, this case suggests that the autologous cervical sympathetic ganglion can be donor tissue for neural transplantation in Parkinson's disease.

Activities of Daily Living↗
PubMed1994

Pretreatment with interleukin-1 enhances survival of sympathetic ganglionic neuron grafts.

The effects of pretreatment with interleukin-1 (IL-1) on neurite growth and cell survival of rat superior cervical ganglion (SCG) explants were examined. Neonate rat SCG explants were cultured with serum-containing growth media. Pretreatment with IL-1 beta (30 U/ml) for 3 hours stimulated neurite outgrowth of the SCG explant, which was inhibited by the addition of anti-nerve growth factor (NGF) antibody to the growth medium. Adult rat autologous SCG with the same pretreatment and non-treated ganglia were transplanted into the lateral ventricle. Histological evaluation of the grafts 2 weeks after transplantation revealed that the pretreated SCG cells survived better. Pretreatment with IL-1 may achieve the NGF-mediated neurotrophic effect in sympathetic ganglionic neurons resulting in enhanced graft survival.

Animals↗
PubMed1994

[Histological analysis of craniopharyngiomas--with special reference to their histological origin and differentiation].

The histogenesis of craniopharyngiomas was immunohistochemically studied on the basis of cytokeratins (CK) expression, with special reference to histological subtype, i.e., the squamous type (Sq) and adamantinomatous type (Ad). Alcian-Blue staining and immunohistochemical expression of secretory component were also studied to assess secretory activity. Although combined expression of simple-, stratified-, and skin-type CK was detected in both Sq and Ad, the pattern of expression in Sq and Ad was different. Sq displayed epidermal differentiation of CK, and secretory activity was limited to the apical cells of Sq. Based on these findings, the histogenesis of Sq appeared to be from Rathke's pouch, but that of Ad remained obscure.

Adolescent↗
PubMed1994

[Transcortical sensory aphasia in a patient with metastatic brain tumor in the left frontal lobe].

We reported a case of a 62-year-old right-handed woman who had transcortical sensory aphasia caused by a metastatic brain tumor in the left frontal lobe. She had mild right hemiparesis involving the face, without hyperactive tendon reflexes. She had neither sensory disturbance nor other cranial nerve deficits. Her spontaneous speech was fluent, and she sometimes had echolalia. Her object naming, word fluency, verbal comprehension and writing were severely disturbed. This contrasted with full preservation of repetition of phonemes and short sentences. Reading of words was preserved. CT scan revealed a subcortical lesion in the left superior frontal gyrus. Gd-enhanced MRI showed a ring-enhanced mass lesion in the frontal lobe outside of Broca's area. We thereby concluded that transcortical sensory aphasia may be caused by frontal lobe lesion independent of the perisylvian speech areas.

Adenocarcinoma, Papillary↗
PubMed1994

Clinicopathological study of lymphomas in the central nervous system--with the reference to the recurrence and proliferative activity.

Nine cases of CNS lymphomas obtained by surgical resection or biopsy between 1984 and 1991 were examined. One case of intraorbital lymphoma was also studied. All patients underwent radiotherapy. In addition, 7 underwent steroid therapy and 4 underwent chemotherapy. The case comprised the following (LSG classification): small cell type (3), medium cell type (1), large cell type (3), and medium and large cell type (3). Immunohistochemically, LCA and B-26 immunopositivity were seen in all cases. Cytoplasmic Ig immunopositivity was observed in five cases. The mean AgNORs number was 4.63 (range: 1.8-7.2). The mean PCNA SI was 26.75 (range: 10.2-39.7). No correlation was found between LSG classification and proliferative activity. Although no correlation was found between AgNORs number and recurrence, the recurrent group showed tendency to have more AgNORs that the non-recurrent group. Although no correlation was found between PCNA SI and recurrence, the recurrent group showed tendency to have a higher PCNA SI than the non-recurrent group. The proliferative activity in AgNORs and PCNA studies may be considered as a prognostic indicator in CNS lymphomas.

Adult↗
PubMed1994

Cellular differentiation, secretory and proliferative activities of craniopharyngiomas.

The cellular differentiation of craniopharyngiomas was studied immunohistochemically by determining the expression of cytokeratins. Alcian-Blue staining was used to assess secretory activity and expression of AgNORs and PCNA as indicators of proliferative activity. Both, tumors of the adamantinomatous type and of the squamous type expressed complex type cytokeratins, with skin type differentiation being noted in some cases. In addition, epidermal differentiation of cytokeratins was found in the squamous types. Intracellular Alcian-Blue staining was limited to apical cells of tumors of the squamous type. Neither AgNORs staining nor PCNA staining proved statistically significant results with respect to the histological type of tumor or patient's age. However, PCNA staining was predominantly noted in basal cells of the squamous type tumors. Although their ultimate significance remains to be established, the results presented provide additional evidence with regard to the possible origin of both craniopharyngioma types, and suggest the potential value of some of the parameters studied as prognostic indicators.

Adolescent↗
PubMed1994

Computed topographic electroencephalographic study in left hemiplegic patients with higher cortical dysfunction.

Computed topographic electroencephalography (EEG) was performed on patients with right hemispheric injury due to cerebral infarction to investigate the relationship of wave form pattern with neurologic and neuropsychologic data and activities of daily living (ADL). Neurologic signs, unilateral spatial neglect, motor impersistence, and constructional apraxia were found to have no relation to the wave form pattern of computed topographic EEG. In patients with abnormalities detected by the "Mini-Mental State" examination (MMSE) or the "Kanahiroi" test, and in patients with abnormalities in word fluency, extensive slowing of EEG frequency was commonly observed ipsilateral to the side of the lesion or bilaterally, and the ADL were frequently poor. In contrast, among the patients with slow waves and retained alpha waves, the MMSE, "Kana-hiroi" test, word fluency, and ADL were less abnormal. Computed topographic EEG may thus be a useful tool to evaluate neuropsychological status in rehabilitation patients with cerebral infarction.

Activities of Daily Living↗
PubMed1993

A case of vessel perforation during interventional neuroradiological procedure. Operative findings of the perforated vessel.

A case of vessel perforation by a guide wire during an interventional neuroradiological procedure is reported. The patient was a 59-year-old woman with a left frontal basal arteriovenous malformation (AVM) fed by the left anterior cerebral artery. Transarterial embolization of the AVM was attempted. During the procedure, vessel perforation by the guide wire occurred at the left A1-A2 junction and resulted in subarachnoid hemorrhage, which stopped spontaneously. The patient developed progressive obstructive hydrocephalus, and surgical treatment was performed. The AVM was totally removed after ventricular drainage, and the arterial perforation site was explored. When clot around the left A1-A2 junction was removed, hemorrhage recurred. This hemorrhage was similar to what has been observed when a small perforating artery was avulsed. The hemorrhage site was coagulated under temporary occlusion of both A1 segments. Surgical intervention was probably not necessary for this type of bleeding if it had stopped spontaneously, because the rebleeding from the small pinhole would be unlikely, and the operation was more hazardous than the usual aneurysmal surgery.

Cerebral Arteries↗
PubMed1993

Complex occipital arteriovenous fistula associated with neurofibromatosis treated by embolization and surgery. Case report.

It is well known that neurofibromatosis is associated with various types of arteriovenous fistulas (AVF), but association with an occipital AVF has not been reported. We are reporting this case which was successfully treated with a combination of embolization and surgery. Superselective angiography defines the anatomic details of the fistula and intraoperative digital subtraction angiography (DSA) facilitates the surgery to cure the fistula. It is important to identify the best therapeutic options using angiographic information to treat a complex arteriovenous fistula.

Adult↗
PubMed1993

Percutaneous transluminal angioplasty for the M2 portion vasospasm following SAH: development of the new microballoon and report of cases.

A new silicone microballoon was developed for the percutaneous transluminal angioplasty of smaller intracranial vessels, such as A1, A2 and M2. This balloon was 0.5 x 2.0 mm in the deflated condition and became 2.2 x 6.5 mm inflated with 0.02 mL of fluid, and its bursting pressure was 2 atm. Two illustrative cases are presented. The first case was not treated in the M2 distribution. The second case of vasospasm of the left M2 portion was successfully treated with this new balloon, with prompt improvement of the neurological condition and cerebral circulation. The usefulness of our microballoon in treating a patient with vasospasm of small intracranial arteries is discussed.

Angioplasty, Balloon↗
PubMed1993

Cerebral blood flow in mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes.

BACKGROUND AND PURPOSE: The precise mechanism of neurological symptoms with mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes (MELAS) is still controversial. We investigated the correlation between strokelike episodes and cerebral blood flow in two patients with MELAS and discuss the pathogenesis of strokelike episodes with MELAS. SUMMARY OF REPORT: Cerebral dynamic computed tomography and cerebral angiography were used to measure cerebral circulation in the first case, that of a 20-year-old woman with MELAS. The second subject was a 13-year-old female who was studied with xenon-enhanced computed tomography. The cerebral blood flow studies were performed 3-72 hours after the onset of strokelike episodes. Serial cerebral angiography, dynamic computed tomography, and xenon-enhanced computed tomography showed vasodilation localized in the affected cerebral cortexes during strokelike episodes, without any reduction in regional cerebral blood flow. CONCLUSIONS: Our study suggests that the strokelike episodes associated with MELAS are different in origin from ischemic stroke.

Adolescent↗
PubMed1993

Influence of regional cerebral blood flow on event-related potential (P300).

The relationships between event-related potential (P300), higher brain functions, and regional cerebral blood flow (rCBF) were examined in 31 neurosurgical patients. The P300 latency, evaluated by an acoustic "odd-ball" paradigm, was normal in 14 and prolonged in 17 patients. Fourteen of 17 prolonged P300 patients had reduced rCBF in the right cerebral hemisphere, especially the frontal lobe and/or thalamus. There was a significant inverse relationship between P300 latency and laterality index (rt rCBF/lt rCBF) in the frontal lobe. Prolonged P300 patients revealed significant abnormalities in psychological tests compared to normal P300 patients. There were significant inverse relationships between the P300 latency and "orientation" and "memory" test scores. Decreased rCBF in the right cerebral hemisphere, especially the frontal lobe and/or thalamus, is associated with prolonged P300 latency, suggesting that the right cerebral hemisphere is important in human cognitive processes.

Adult↗
PubMed1993

Acute subdural hematoma associated with vacuolated meningioma--case report.

A 67-year-old male presented with a left temporal convexity vacuolated meningioma associated with acute subdural hematoma manifesting as sudden headache, nausea, and vomiting without neurological deficit. Magnetic resonance imaging disclosed an extra-axial mass as mixed low- and high-signal intensities and a crescent high-intensity area in the left convexity. Histological examination diagnosed meningotheliomatous meningioma with vacuolated components and hemorrhagic foci. The tumor and hematoma were removed without postoperative complications.

Aged↗