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Featured researches published by Masaaki Nagatani.


Neurosurgery | 1987

Glioblastoma after Radiotherapy for Craniopharyngioma: Case Report

Yukitaka Ushio; Norio Arita; Toshiki Yoshimine; Masaaki Nagatani; Heitaro Mogami

A 6-year-old girl developed a glioblastoma in the basal ganglia and brain stem 5 years after surgical excision and local irradiation (5460 cGy) for craniopharyngioma. Clinical and histological details are presented, and the literature on radiation-induced gliomas is reviewed.


Neurosurgery | 1987

Primary myxoma in the pituitary fossa: case report.

Masaaki Nagatani; Shintaro Mori; Noboru Takimoto; Norio Arita; Yukitaka Ushio; Toru Hayakawa; Moritetsu Gen; Tohru Uozumi; Heitaro Mogami

A case of primary myxoma in the pituitary fossa is described. The tumor presented as an intrasellar and suprasellar mass and was successfully removed during a transsphenoidal operation. It was verified as a myxoma by histopathological studies, and there was no evidence that it was a metastasis. This is thought to be the first report of this tumor occurring in the pituitary fossa.


Journal of Neuro-oncology | 1988

Intrathecal ACNU — a new therapeutic approach against malignant leptomeningeal tumors

Norio Arita; Yukitaka Ushio; Toru Hayakawa; Masaaki Nagatani; Tzuu-Yuan Huang; Shuichi Izumoto; Heitaro Mogami

SummaryPharmacokinetics, toxicity and therapeutic efficacy of intrathecal ACNU, 3-((4-amino-2-methyl-5-pyrimidinyl)methyl)-1-(2-chloroethyl)-1-nitrosourea, were studied in rats to determine if it is a new and effective method for the treatment of malignant leptomeningeal tumors. Pharmacokinetics of intracisternally administered ACNU was studied by macroscopial autoradiography using 14C-labeled ACNU. It was demonstrated that intracisternally administered ACNU distributed in the subarachnoid space and subpial layer of the brain in high concentration and was rapidly eliminated into the systemic circulation. The diffusional transport of ACNU into the deeper part of the brain was limited. More than 3.0 mg/kg of intracisternal ACNU induced progressive loss of the weight of body in normal rats, and 80% of the rat given 6.0 mg/kg died. Increase of capillary permeability, neuronal loss and gliosis were observed in the marginal layer of the brain facing to the subarachnoid space in the rat given more than 3.0 mg/kg of ACNU. Systemic and local toxicity was not observed in the rat given less than 1.5 mg/kg. Therapeutic effect of intrathecal ACNU against leptomeningeal tumors was evaluated in the rat with meningeal carcinomatosis induced by intracisternal inoculation of Walker 256 carcinosarcoma cells. The median survival time of the rat treated with 1.5 mg/kg of intracisternal ACNU once on day 2 or on day 5 after tumor inoculation was significantly prolonged by 173%, and 214% at maximum, respectively, as compared with that of the untreated animal. These findings suggest that intrathecal ACNU may be of value for clinical trial against leptomeningeal tumors.


Surgical Neurology | 1986

Treatment of prolactinoma based on the results of transsphenoidal operations

Youichi Saitoh; Shintaro Mori; Norio Arita; Masaaki Nagatani; Toru Hayakawa; Kiyoshi Koizumi; Osamu Tanizawa; Tohru Uozumi; Heitaro Mogami

Ninety-eight patients (16 male, 82 female) with prolactinomas were treated by transsphenoidal operation. The postoperative course was closely related to the tumor size and the preoperative levels of serum prolactin. In 37 (74%) of 50 patients with microadenomas, the levels of serum prolactin returned to normal postoperatively. There were 48 patients with macroadenomas; 27 of these were expansive and 21 were invasive. In 9 (33%) of the 27 patients with expansive macroadenomas, the postoperative levels of prolactin returned to normal; this was not the case in any of the 21 patients with invasive macroadenomas. Of 81 premenopausal women, 35 (43%) resumed normal menstruation postoperatively. All patients with preoperative deficits in the visual field experienced postoperative improvement. There were no postoperative deaths or serious complications in this series. Our data indicate that microprolactinomas are highly curable by transsphenoidal operation alone. In women who plan to have children, prolactinomas should be removed immediately. On the other hand, in patients with macroprolactinomas who manifest high levels of serum prolactin, initial treatment with bromocriptine should be considered because there is little hope for surgical cure and postoperative bromocriptine treatment might be necessary.


Headache | 2005

A Case Simulating Ophthalomoplegic Migraine: Clinicopathological Study

Kazuyoshi Morimoto; Masaaki Nagatani; Heitaro Mogami

SYNOPSIS


Progress in Experimental Tumor Research | 1987

Leptomeningeal dissemination of primary brain tumors in children: clinical and experimental studies.

Yukitaka Ushio; Norio Arita; Toru Hayakawa; Kazuo Yamada; S. Koh; Masaaki Nagatani; T. Yoshimine; Heitaro Mogami


Cancer Research | 1987

Distribution of Radiolabeled 1-(4-Amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea Hydrochloride in Rat Brain Tumor: Intraarterial versus Intravenous Administration

Kazuo Yamada; Yukitaka Ushio; Toru Hayakawa; Norio Arita; Tzuu-Yuan Huang; Masaaki Nagatani; Noriko Yamada; Heitaro Mogami


Nō to shinkei Brain and nerve | 1986

[Intrathecal ACNU against malignant leptomeningeal tumors--toxicity and therapeutic effect in experimental animals].

Masaaki Nagatani; Norio Arita; Yukitaka Ushio; Hayakawa T; Tzuu-Yuan H; Toshiki Yoshimine; Mori S; Heitaro Mogami


Nō to shinkei Brain and nerve | 1987

[Distribution of ACNU in the rat brain after intracisternal injection--macroscopical autoradiographic study].

Huang Ty; Norio Arita; Yukitaka Ushio; Hayakawa T; Masaaki Nagatani; Heitaro Mogami


Nō to shinkei Brain and nerve | 1988

[Effect of ACNU against experimental brain tumor--immunohistochemical study using anti-BrdU monoclonal antibody].

Shuichi Izumoto; Norio Arita; Yukitaka Ushio; Toru Hayakawa; Toshiki Yoshimine; Tzuu-Yuan H; Masaaki Nagatani; Oku Y; Heitaro Mogami

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Heitaro Mogami

Memorial Hospital of South Bend

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Toru Hayakawa

Memorial Hospital of South Bend

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