Biomedical subjects

A Nishimoto

Publications and source records attributed to A Nishimoto.

At least 19 recordsLinked to original sources

PubMed1992

Direct thrombosis of aneurysms with cellulose acetate polymer. Part II: Preliminary clinical experience.

The authors report the treatment of seven intracranial aneurysms in six patients with direct infusion of cellulose acetate polymer solution, a new liquid thrombotic material. These aneurysms were considered inoperable because of their size or location, or because of the patient's neurological condition. This material avoids the difficulties associated with balloon occlusion, and completely fills even irregularly shaped aneurysms. Cellulose acetate polymer solution hardens in about 5 minutes and remains solid once inside the aneurysm. Because this technique is less invasive than surgery, it can be used for high-risk patients in the acute stage of subarachnoid hemorrhage. Transient motor aphasia occurred in one patient. A small residual neck, which caused rebleeding 3 months after the treatment, remained in another patient. This article describes the new material, the procedure for direct thrombosis, and preliminary clinical results.

Adult↗

PubMed1992

[Analysis of tumor-infiltrating lymphocyte in primary malignant lymphoma of the central nervous system using double immunofluorescence staining method].

Three cases of malignant lymphoma were examined immunohistochemically using anti-Leu monoclonal antibodies (MAB) against B lymphocytes, T lymphocytes subsets, NK cells, IL-2 receptor. In all three cases tumor cells were stained with anti-B cell's MABs, that is they were diagnosed as B cell type of malignant lymphoma. Moderate tumor-infiltrating lymphocytes in the parenchyma or around blood vessels were observed, and majority of these cells were T lymphocytes, demonstrating Leu 2a or Leu 3a + 3b positive phenotypes. IL-2 receptor positive cells also found in the parenchyma of these tumors. T lymphocyte subsets, such as Leu 2a positive cells and Leu 3a + 3b positive cells, were analyzed by means of double immunofluorescence staining method using the combination of Leu 2a and Leu15, or Leu 3a + 3b and Leu 8 MABs. This method demonstrated that most of Leu 2a positive cells were negative for Leu 15 and that the majority of Leu 3a + 3b positive cells were negative for Leu 8. These results suggested that tumor-infiltrating lymphocytes in the malignant lymphoma were mainly activated cytotoxic or helper T cells.

Brain Neoplasms↗

PubMed1992

[Unbranched-site aneurysm of intracranial internal carotid artery].

Most intracranial saccular aneurysms arise from the angle between a parent vessel and an arterial branch. Saccular aneurysms without relation to any arterial branch are rare. During the last 24 years, 210 patients with intracranial internal carotid artery (ICA) aneurysms were directly operated on at our institution. We found eight saccular aneurysms arising from intracranial ICA without relation to any arterial branch. So we call them unbranched-site aneurysms of intracranial ICA, and describe their unique characteristics. Of the eight cases with unbranched-site aneurysm of intracranial ICA, three were men and five were women. The age ranged from 31 to 61 years with an average age of 48. Seven cases suffered a subarachnoid hemorrhage due to ruptured unbranched-site aneurysm, and the other case had been admitted to our department because of accompanying ruptured left internal carotid-posterior communicating aneurysm. All cases of unbranched-site aneurysm presented intraoperative and/or angiographic findings of arteriosclerosis, and five of the patients had a past history of hypertension. Of the four unbranched-site aneurysms at the C2 portion of ICA, two arose from the lateral wall, one arose from the superior wall and the other arose from the infero-lateral wall of ICA. Of the four unbranched-site aneurysms at the C1 portion of ICA, three arose from the superior wall and the other arose from the supero-medial wall of ICA. Radical operation was performed in all cases and intraoperative rupture occurred in two cases. It was suggested that arteriosclerotic change in the arterial wall, and local hemodynamic stress played important roles in the development of unbranched-site aneurysms of intracranial ICA.

Adult↗

PubMed1992

[Study on the extent of peritumoral edema in glioma: its correlation with the proliferative potential and tumor-infiltrating mononuclear cells].

The correlation between the extent of peritumoral edema and the proliferative potential or the infiltration of mononuclear cells was studied in 17 gliomas. The peritumoral edema was evaluated on contrast enhanced CT scan as the ratio of the low density area around the tumor to the enhanced high density area. The proliferative potential and the infiltration of mononuclear cells into the tumor were investigated immunohistochemically using monoclonal antibody (MAb) against DNA polymerase alpha and anti-Leu MAb's respectively. There was a significant correlation between the extent of the peritumoral edema and the percentage of DNA polymerase alpha positive cells. The degree of the infiltration of mononuclear cells into the tumor tissue also correlated with the extent of peritumoral edema. In gliomas with high proliferative potential and/or severe infiltration of mononuclear cells, the peritumoral edema may be aggravated by disruption of the blood-brain-barrier and increased vascular permeability.

Brain Edema↗

PubMed1991

Hemifacial spasm due to cerebellopontine angle epidermoid tumor--case report.

The authors report a case of cerebellopontine angle epidermoid presenting as typical hemifacial spasm. A 33-year-old male had experienced intermittent right hemifacial spasm for 2 years. Cranial nerve examination was otherwise normal, including auditory and trigeminal nerve functions. Metrizamide computed tomographic cisternography and magnetic resonance imaging demonstrated a characteristic epidermoid tumor. The tumor was totally removed. Postoperatively, no facial spasm or other facial nerve dysfunction was noted.

Adult↗

PubMed1991

[Immunohistochemical study for choroid plexus papillomas and ependymomas].

An immunohistochemical study of glial fibrillary acidic protein (GFAP), S-100 protein, cytokeratin (CKER), epithelial membrane antigen (EMA), and transthyretin (TTR) was carried out on 11 cases of choroid plexus papilloma (CPP) and 19 of ependymoma, using the peroxidase antiperoxidase technique. Among the 11 cases of CPP, all 11 were positive for CKER, EMA, and TTR, 10 for S-100 protein, and five for GFAP. Most of the GFAP-positive papilloma cells were simultaneously positive for CKER. However, these GFAP-positive cells were negative for TTR. Among the 19 cases of ependymoma, 16 were positive for GFAP, 17 for S-100 protein, three for CKER, eight for EMA, but none for TTR. Some GFAP-positive cells were also stained for CKER. However, TTR was not found in any of the ependymal cells. These findings suggested that CPP cells which show ependymal or glial differentiation lost the ability to synthesize TTR which is known to be synthesized in the epithelial cells of the choroid plexus. The more GFAP-positive cells present in a CPP, fewer TTR-positive cells are present. Though CPPs are usually easily distinguishable from ependymomas, occasional doubt arises concerning the differential diagnosis between CPP and papillary ependymoma. TTR can be a very useful diagnostic marker of CPP.

Adult↗

PubMed1991

Influence of IL-6 on proliferation and differentiation of tonsillar lymphocytes and detection of IL-6 producing cells in tonsil.

When tonsillar B cells were cultured in the presence of exogenous interleukin-6 (IL-6), a small portion of them differentiated into plasma cells which seemed to have IL-6 receptors on their surfaces. The number of plasma cells tended to be greater in the tonsils of children than in the tonsils of adults. When tonsillar cells collected by Ficoll-Conray's method were cultured in medium containing IL-6, T cells differentiated and the number of activated T cells increased. Of the four subsets of T cells, this effect of IL-6 was strongest on cytotoxic T cells. IL-6-mediated proliferation and activation of cytotoxic T cells tended to be greater in the tonsils of children than in those of adults. IL-6 is produced in some tonsillar macrophages. The number of macrophages producing IL-6 was very different in different subjects. However, the number of macrophages producing IL-6 in tonsils of children tended to be greater than the number in tonsils of adults.

Adolescent↗

PubMed1991

Hemifacial spasm caused by a spontaneous dissecting aneurysm of the vertebral artery. Case report.

The authors describe the first reported case of dissecting aneurysm presenting with hemifacial spasm. The patient was a 58-year-old woman with left hemifacial spasm of 2 years' duration. Cranial nerve examination was otherwise normal and no other clinical symptoms were observed. Vertebral angiography revealed a fusiform enlargement of the left vertebral artery and contrast medium remaining in the intramural false lumen in the venous phase. Microvascular decompression of the facial nerve with wrapping of the aneurysm resulted in complete relief of the hemifacial spasm.

Aortic Dissection↗

PubMed1991

[The effect of a new immunosuppressive agent, FK-506, on xenogeneic neural transplantation in rodents--comparison with cyclosporin A].

The present study was performed to compare the immunosuppressive effect of FK-506 (FK) with cyclosporin A (CyA) in xenogeneic neural transplantation in rodents. The solid grafts of embryonic ventral mesencephalic tissue from 14-day rat embryos were transplanted into the right lateral ventricle of 20 mature male mice using a stereotactic approach, and the mice were sacrificed 14 days after transplantation. The removed brains, which were sectioned coronally, were stained with antibodies against glial fibrillary acidic protein (GFAP), Lyt-2 or tyrosine hydroxylase (TH) in addition to hematoxylin-eosin and Nissl stainings. The subcutaneous (s.c.) administration of FK at a dose of 10.0 mg/kg daily for 14 days enabled the neural xenografts to survive and grow (n = 5), although all of the neural xenografts treated with CyA at a dose of 10.0 mg/kg s.c. (n = 5) or FK at a dose of 1.0 mg/kg s.c. (n = 5) daily for 14 days and ones treated without such an immunosuppressive agent (n = 5) were rejected by immunological reactions. We conclude that FK is a more powerful immunosuppressive agent than CyA in xenogeneic neural transplantation as well as in cardiac and renal allograftings.

Animals↗

PubMed1991

[The effect of chronic treatment of deprenyl in animal models of Parkinson's disease].

Recent studies have demonstrated that deprenyl can delay the progression of parkinsonian syndrome. Deprenyl selectively and irreversibly inhibits the activity of monoamine oxidase-type B (MAO-B), and subsequent enzyme activity requires de novo synthesis of MAO-B. In this study we investigated (1); the effects of deprenyl on striatal dopamine (DA) levels in MPTP-lesioned and undamaged mice and (2); the effect of deprenyl on L-DOPA induced rotational movements in a hemiparkinsonian model monkey. In MPTP-lesioned mice, deprenyl increased the striatal DA levels by 123%, 78% immediately and one week after termination of deprenyl treatment respectively, while by 31%, 24% in MPTP-undamaged mice, respectively. Four weeks after termination of treatment, and the striatal DA was not significant. It shows that deprenyl is effective in elevation of striatal DA at least one week after termination of treatment, and the degree of increase of striatal DA following deprenyl treatment is greater in MPTP-treated mice than in undamaged mice. Deprenyl seemed to be effective longer in a hemiparkinsonian monkey than in rodents. The result suggests that less frequent administration of deprenyl may be effective in controlling side effects of L-DOPA without reducing therapeutic efficacy.

Animals↗

PubMed1991

[Cografting technique in the treatment of Parkinson's disease].

Intracerebral grafting of dopamine containing adrenal chromaffin cells to the brain of experimental animals can ameliorate the symptoms of experimentally induced Parkinson's disease. Clinical trials of adrenal autograft to the patients with Parkinson's disease are on-going with variable results and autopsy cases show poor survivability of grafted chromaffin cells. The present study was performed to determine if transected peripheral nerve could provide sufficient nerve growth factor to enhance the survivability of grafted chromaffin cells. Survivability of grafted chromaffin cells increased when cografts with sciatic nerve were performed, and host dopaminergic fiber recovery was more prominent in mice with cografts than in mice with adrenal grafts alone. Although this enhanced survivability and recovery of host fibers were seen in cografted mice from aging donors, the degree of these effects was greater in cografted mice from young donors. Considering these results, we suggest that methods to increase the survivability of grafted chromaffin cells be explored more deeply because such survivability might be closely related to the functional recovery of patients with Parkinson's disease, using this grafting procedure.

Adrenal Medulla↗

PubMed1991

[Direct embolization with occluding spring embolus for large aneurysm and carotid-cavernous fistula].

The authors describe a technique using occluding spring emboli for direct obliteration of an unclippable large aneurysm, and carotid-cavernous fistula (CCF) which failed to be occluded by transarterial and transvenous approaches. Case 1: This 44 year-old man had a history of head trauma 30 years ago. He was admitted to our department on October 16, 1989, because of an aneurysm incidentally found by a CT scan taken for the examination of his vertigo. Angiograms revealed a large aneurysm at the C3 portion of the right internal carotid artery. A right frontal craniotomy was performed on November 2, 1989, but neck clipping of the aneurysm was impossible, because it was a pseudoaneurysm with quite a fragile neck. Subsequently, fourteen occluding spring emboli were inserted into the aneurysm through a polyethylene catheter directly into the aneurysmal dome. Postoperative angiograms showed almost complete obliteration of the aneurysm with good preservation of the parent artery. Case 2: This 26 year-old woman without a history of head trauma was admitted to our department on May 10, 1989, complaining of right conjunctival injection and exophthalmos. Angiograms revealed a spontaneous CCF which had a single orifice at the C4 portion of the right internal carotid artery and drained through the superior ophthalmic vein and inferior petrosal sinus. Initially, transarterial and transvenous approaches were tried, but the attempts were unsuccessful. Subsequently, a right frontotemporal craniotomy was performed on August 8, 1989, and 27 occluding spring emboli were placed into the cavernous sinus through a polyethylene catheter which had been inserted directly.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

[Basal ganglia germinoma treated with interstitial brachytherapy; case report].

A case of primary intracranial germinoma in the left basal ganglia treated with interstitial brachytherapy was reported. A 15-year-old boy was referred to our hospital for evaluation of right hemiparesis. A CT scan showed a slightly hyperdense mass with multiple cystic low density in the left basal ganglia. The mass was heterogeneously enhanced after intravenous administration of contrast material. T1 weighted image showed a slightly hyperintense mass with cystic components and the mass was heterogeneously enhanced with Gd-DTPA. T2 weighted MR image showed a mixed intensity mass and peritumoral edema. Stereotactic needle biopsy and implantation of 3 catheters for interstitial brachytherapy were performed simultaneously using BRW CT guided stereotactic apparatus. After the histological diagnosis was confirmed to be two cell pattern germinoma, 9 iridium-192 seeds were inserted into the catheters and maintained for 10 days to give 35Gy of irradiation at the tumor periphery. Subsequent CT scans showed marked tumor regression and the clinical symptoms were improved. Germinoma originating in the basal ganglia is rare and hard to diagnose previous to biopsy. Histological confirmation is essential before initiation of treatment because germinoma is commonly thought to be radiosensitive tumor. The interstitial brachytherapy enables selective irradiation of the tumor and actually causes no complications such as bone marrow suppression or cerebral atrophy. The neuroradiological findings, especially of CT scan and MRI, were presented and the strategy for treatment of germinoma in basal ganglia was discussed.

Adolescent↗

PubMed1991

[Cografts of adrenal medulla and peripheral nerve in a mouse model of Parkinson's disease].

Systemic injection of MPTP damages the nigrostriatal dopaminergic system in C57B1/6 mice. Since transected peripheral nerve segments are known to produce nerve growth factor, we performed adrenal medullary grafts or cografts of adrenal medulla and sciatic nerve into the striatum of MPTP-treated mice, and compared the survivability of grafted chromaffin cells and the recovery of intrinsic host dopaminergic fibers. Survivability of grafted chromaffin cells increased when cografts with sciatic nerve were made, and host dopaminergic fiber recovery was more prominent in mice with cografts than in mice with adrenal grafts alone. The degree of recovery of host intrinsic dopaminergic fibers was greater in younger host striatum than in older host striatum. We conclude that cografts of adrenal medulla and sciatic nerve increase the survivability of grafted chromaffin cells better than adrenal medullary grafts alone, and that survivability of grafted chromaffin cells promotes host dopaminergic fiber recovery.

Adrenal Medulla↗

PubMed1990

Central neurocytoma--case report.

The authors present a case of central neurocytoma in a 34-year-old female who had experienced intermittent headaches over a 10-year period. On computed tomographic (CT) scans and magnetic resonance images, the tumor appeared as a large, calcified mass occupying both lateral ventricles. A right parieto-occipital craniotomy was performed and the tumor was totally removed. While the light microscopic findings suggested a diagnosis of oligodendroglioma, electron microscopic examination demonstrated clear vesicles, microtubules, and synaptic structures within the abundant cytoplasmic processes of the tumor cells. Immunohistochemical examination showed the tumor cells to be strongly positive for neuron-specific enolase, sparsely positive for S-100 protein, and negative for glial fibrillary acidic protein. The final histological diagnosis was central neurocytoma. The postoperative course was uneventful and no further treatment was administered. She has no neurological deficits and CT has shown no evidence of recurrence during the 2 years since her surgery. Central neurocytoma is a rare tumor arising in the lateral ventricle, and the diagnosis is mainly based on electron microscopic findings. Since central neurocytoma appears to have a good prognosis following total removal alone, it is very important to distinguish between this and other ventricular tumors.

Adult↗

PubMed1990

Immunohistochemical demonstration of DNA polymerase alpha in human brain-tumor cells.

The proliferative capacity of brain-tumor cells was analyzed in vitro and in situ using monoclonal antibody (MAb) against deoxyribonucleic acid (DNA) polymerase alpha. For the in vitro studies, two cultured human glioma cell lines were investigated using MAb against DNA polymerase alpha, the MAb Ki-67, a serum against proliferating cell nuclear antigen (PCNA/cyclin), bromodeoxyuridine (BUdR), and an anti-BUdR MAb. During exponential growth of the cells, the percentage of polymerase alpha-positive cells (the "polymerase alpha score") ranged from 72.0% to 77.1%, the Ki-67-positive cells (the "Ki-67 score") ranged from 43.4% to 59.4%, the PCNA/cyclin-positive cells from 30.9% to 41.4%, and the BUdR labeling index from 28.6% to 39.3%. For the in situ studies, tissue from 60 human brain tumors and from two normal human brains was investigated and the polymerase alpha scores and Ki-67 scores were compared. In normal brain tissue, no immunostaining was found by either method. In brain tumors, both the polymerase alpha scores and the Ki-67 scores correlated with the histological grade of malignancy. Polymerase alpha scores were generally higher than Ki-67 scores in the same specimen, especially in malignant brain tumors. These findings suggest that immunostaining of DNA polymerase alpha is a convenient and important new method by which to estimate the cellular proliferation rate of brain tumors. Polymerase alpha scores may be closer to the growth fraction of the individual tumor than the MAb Ki-67 or other scores.

Antibodies, Monoclonal↗

PubMed1990

[Recovery of nigrostriatal and mesolimbic dopaminergic system following administration of ganglioside in MPTP-treated mice].

The effects of systemic injection of GM 1 ganglioside on dopaminergic (DA) nigrostriatal and mesolimbic system following 1-methyl-4-phenyl-1, 2,3,6-tetrahydropyridine (MPTP) have been studied in C 57 BL/6 mice. MPTP treatment (4 x 20 mg/kg i.p. given 12 hr apart) resulted in significant depletion of DA concentration in the major terminal fields of the nigrostriatal and mesolimbic DA systems, i.e. dorsal striatum, ventral striatum, nucleus accumbens and olfactory tubercle 5 weeks after treatment in young (2 month old) mice. In aging (12 month old) mice treated with MPTP, significant depletion of DA concentration was observed in the cell body regions, i.e. substantia nigra and ventral tegmental area in addition to the major terminal fields, suggesting that the effect of MPTP is more widespread in aging mice. Although GM 1 ganglioside treatment (30 mg/kg, i.p. daily for 5 weeks) partially restored DA concentration in every major terminal field in young mice, such an apparent recovery was not seen in aging mice. GM 1 ganglioside treatment also reduced the increased 3,4-dihydroxyphenylacetic acid (DOPAC)/DA ratio following MPTP injection in the striatum of young mice, but such an effect was not observed in aging mice. We conclude that DA nigrostriatal and mesolimbic system in aging mice demonstrates reduced regenerative capacity following MPTP depletion compared with young mice, and the beneficial effect of GM 1 ganglioside for the recovery of DA nigrostriatal and mesolimbic system neurons declines with age.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗

PubMed1990

[Adrenal medullary graft induces recovery of the host nigrostriatal dopaminergic system in MPTP-induced mouse model of Parkinson's disease].

C57BL/6 mice show decreased dopaminergic fibers and dopamine concentration in the striatum following systemic injection of 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP). We have investigated the effect of adrenal medullary grafts into the striatum of young mice treated with MPTP. Enhanced recovery of the host nigrostriatal dopaminergic system was observed in those adrenal medullary grafted mice. However, this recovery was influenced by the survivability of grafted chromaffin cells and adrenal chromaffin cells from younger donors survived better than those from older donors. Since adrenal chromaffin cells contain several kinds of neurotrophic factors such as basic fibroblast growth factor and gangliosides, survivability of those grafted chromaffin cells may play an important role concerning recovery of the host intrinsic dopaminergic fibers. Adrenal medullary grafts to the patients with Parkinson's disease are currently under way in a large number of hospitals and we suggest more consideration be given to methods which lead to enhance the grafted chromaffin cell survival, since those survivability might be closely related to the functional recovery of these patients.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗