PubMed Health⌕ Search

Biomedical subjects

S Nakasu

Publications and source records attributed to S Nakasu.

At least 37 records · Page 2Linked to original sources
PubMed1996

Clinical significance of Ki-67 staining index in acoustic neurinoma.

The correlation between various clinical parameters and MIB-1 (Ki-67) staining indices was evaluated in 58 acoustic neurinomas. The index ranged from 0.37% to 6.61% (mean 1.70%), and did not correlate with age, sex, or initial tumor volume. Sixteen of the 18 tumors removed subtotally or partially showed regrowth, and two showed a volume reduction. The 16 patients with regrowth were divided into two groups according to Ki-67 staining index, < 2.00% and > or = 2.00%. These groups had a significant difference in tumor doubling time (TDT). In addition, there was a significant logarithmic correlation between Ki-67 staining index and TDT. Ki-67 staining index can be used as an index of regrowth rate in partially or subtotally removed acoustic neurinomas. Intraoperative assessment of Ki-67 staining index may be useful for better management planning as well as the estimation of prognosis.

Adolescent↗
PubMed1995

Meningioma: proliferating potential and clinicoradiological features.

We examined the proliferative potentials of meningiomas in 120 patients using the MIB-1 antibody against the Ki-67 antigen and compared them with the clinicoradiological features. The Ki-67 staining index (SI) did not relate to the age and sex of the patients or the location of the tumors. Asymptomatic meningiomas showed significantly lower SIs (mean +/- standard deviation [SD], 0.87 +/- 0.56%) than symptomatic meningiomas (mean +/- SD, 1.63 +/- 2.17%). We found no relation between SIs and clinical symptoms and signs in the symptomatic meningiomas. A weak correlation was found between the size of tumors and Ki-67 SIs (r = 0.21; P = 0.024). There were significant differences in SIs between calcified (mean +/- SD, 0.77 +/- 0.41%) and noncalcified tumor (mean +/- SD, 1.75 +/- 2.25%). Diffusely calcified tumors (mean +/- SD, 0.57 +/- 0.34%) showed lower SIs than focally calcified tumors (mean +/- SD, 0.92 +/- 0.41%). Lobulated tumors showed higher SIs (mean +/- SD, 2.85 +/- 3.68%) than round tumors (mean +/- SD, 1.06 +/- 0.67%). Tumors with perifocal edema or unclear borders had higher SIs than did those without such features. Signal intensities on T1-weighted magnetic resonance images had no relation to SIs, whereas low-intensity tumors on T2-weighted images, most of which presented diffuse calcification on computed tomographic scans, showed lower SIs. This study indicates that several clinicoradiological features relate to the proliferative potential of meningiomas and that they may contribute to the management of patients.

Adult↗
PubMed1995

[Pineocytoma associated with a cyst: report of a case].

We report a case of pineocytoma associated with an unusually large cyst. A 15-year-old boy was admitted with a complaint of intermittent headache. Neurological examination was normal except for bilateral papilledema. CT scan showed triventricular hydrocephalus and a large mass. A solid portion of the tumor in the pineal and retrothalamic areas was isodense, and contained massive calcification on CT. A huge cystic portion extended far into the infratentorial, supracellebellar area. On MR, the solid tumor showed isointensity on T1-WI and iso- to high intensity on T2-WI, and was enhanced by Gd-DTPA. After a ventriculo-peritoneal shunt, the tumor was partially removed through an occipital supratentorial approach. Histological examination revealed a pineocytoma with neuronal and astrocytic differentiations. Reviewing the literature, it is most unusual to find a pineocytoma associated with a huge cyst as was seen in this case.

Adolescent↗
PubMed1995

[Congenital dermoid cyst over the anterior fontanelle: case report].

We report a case of a 35-month-old Japanese boy harboring a dermoid cyst in the region of the anterior fontanelle, which is rarely reported among Japanese. A small soft subcutaneous mass was noticed in the mid-frontal region at the age of 6 months. On admission, a soft, nontender round mass (2.5cm in diameter) was located over the anterior fontanelle. Transillumination was negative. Neurological examination yielded normal findings. MRI showed a well-circumscribed mass, which was slightly hypointense on T1W1 and hyperintense on T2W1. Midsagittal MRI showed no intracranial extension. At operation, a well-encapsulated mass was found beneath the pericranium, which was easily dissected from the underlying dura mater and removed. The tumor contained caseous material and several hairs. Microscopically, the cyst wall consisted of connective tissues lined by stratified squamous epithelium. Sebaceous glands and hair follicles were found in the subepithelial layer. It is important to confirm preoperatively whether or not the extracranial mass extends into the intracranial cavity. For this purpose, midsagittal or coronal MRI seems to be most useful.

Child, Preschool↗
PubMed1994

bcl-2 protein expression in tumors of the central nervous system.

bcl-2 protein (BCL-2) expression was immunohistochemically studied in 140 varied central nervous system tumors. The protein was most frequently expressed in neurinomas and ependymomas, and in normal ependymal cells and Schwann cells. Most pituitary adenomas could be classified into one of two subgroups, diffusely positive or diffusely negative tumors, while BCL-2 localized heterogeneously in normal pituitary glands. Although the protein was not detected in normal astrocytes, it was positive in reactive hypertrophic astrocytes observed in various pathological conditions. Similarly, astrocytic tumor cells often expressed BCL-2. Since low-grade astrocytomas more often exhibited the protein than malignant gliomas, the degree of BCL-2 expression appeared to be related to the degree of malignancy of the gliomas. On the other hand, 7 out of 17 recurrent gliomas and medulloblastomas showed an increase in the frequency of protein expression compared with specimens from initial treatments. One recurrent astrocytic tumor which demonstrated anaplastic change showed a decrease in the frequency of BCL-2-positive cells. It is concluded that the frequency of BCL-2 expression in CNS tumors is increased when the non-neoplastic counterparts of the tumors exhibit the protein. Although it has been reported that overexpression of BCL-2 protects cells from damage by radiation and/or chemotherapy, we could not find any significant relationship between the degree of BCL-2 expression and the length of survival of patients with glioblastomas or medulloblastomas.

Adenoma↗
PubMed1994

Immunohistochemical localization of glycosaminoglycans in experimental rat glioma models.

Changes of glycosaminoglycan distribution in and around C6 glioma and ethylnitrosourea(ENU)-induced glioma in rats were investigated using monoclonal antibodies that specifically recognize epitopes on chondroitin-0-sulfate proteoglycan (C-0-S), chondroitin-4-sulfate proteoglycan (C-4-S), dermatan sulfate proteoglycan (DS), chondroitin-6-sulfate proteoglycan (C-6-S) and keratan sulfate proteoglycan (KS) after chondroitinase ABC digestion. In the normal brain tissues, C-0-S was located on the surface of the neurons. In addition, extracellular staining in the cerebral cortex and axoplasmic staining in the brain stem and the reticular thalamic nucleus were seen. C-0-S was negative, however, both in the C6 and ENU-induced gliomas. C-4-S or DS was detected only in some of the neurons in the normal brain tissues. They were detected in the peripheral part of the ENU-induced gliomas, but not in the C6 gliomas. C-6-S was located on the surface of some neurons and in the white matter of the normal brain, but it was not detected in C6 gliomas. In all ENU-induced gliomas, C-6-S was identified in the adventitia of the vascular structures within the tumor. In some of them, C-6-S appeared in the peripheral part of the tumor. KS was immunostained in the glial cells in the hippocampus, corpus callosum, brain stem, and the floor of the third ventricle. It was also detected in the peritumoral brain tissues both in the C6 and ENU-induced rat gliomas. The significance of glycosaminoglycans in these glioma models was discussed.

Animals↗
PubMed1994

Proliferating cell nuclear antigen expression in rat glioma model: comparison with bromodeoxyuridine labeling index.

The usefulness of proliferating cell nuclear antigen (PCNA) immunostaining for estimating the growth fraction in glial tumors was evaluated in ethylnitrosourea-induced rat gliomas. The PCNA labeling index was compared with the bromodeoxyuridine (BrdU) labeling index, using alternate serial sections fixed either in 10% formalin or in periodonate-lysine-paraformaldehyde (PLP). The PCNA labeling index was significantly correlated with the BrdU labeling index if cells with only faint PCNA staining were excluded. Differences in PCNA staining were noted between the two fixatives. The number of PCNA-positive cells in PLP-fixed material was greater than in 10% formalin-fixed material, but showed a poorer correlation with BrdU labeling index. Over-fixation in formalin reduced the number of positive cells. Although peritumoral tissue did not exhibit overexpression of PCNA, the ependymal lining was weakly stained even in areas distant from the tumor. PCNA labeling index is a useful method to estimate the growth fraction when the materials are processed in a controlled way. When clinical specimens with uncertain preparation are used, care is required in interpreting the results.

Animals↗
PubMed1994

Lectin binding and bcl-2 protein expression in craniopharyngiomas.

The maturation process of basal cells in craniopharyngiomas was studied using a panel of lectins, and antibodies against cytokeratin 13 and bcl-2 protein, using oral mucosa for comparison. Seven lectins were employed: peanut (Arachis hypogaea) agglutinin, Dolichos biflorus agglutinin (DBA), Ulex europaeus agglutinin-I (UEA-I), soybean agglutinin, Ricinus communis agglutinin-I, succinyl wheat germ agglutinin, and Pisum sativum agglutinin. DBA and cytokeratin 13 stainings of the suprabasal cells in craniopharyngiomas were comparable to those of the oral mucosa, but not to those of the skin. Staining patterns of the basal cells in the oral mucosa and craniopharyngiomas were generally similar, but UEA-I binding and bcl-2 protein expression in suprabasal cells differed. The difference appeared to be due to a disturbance in the differentiation of the basal cells, because only a small fraction of the basal cells followed a normal maturation process in craniopharyngiomas in comparison to the oral mucosa. The expression of bcl-2 protein may be involved in the pathogenesis of craniopharyngiomas.

Binding Sites↗
PubMed1994

[Suprasellar ectopic pituitary adenoma: report of a case].

An extremely rare case of an ectopic pituitary adenoma in the suprasellar region is reported. A 57-year-old man was referred to us in March, 1993, because of bitemporal hemianopsia. Magnetic resonance imaging (MRI) and computed tomography (CT) revealed a well-circumscribed enhancing mass in the suprasellar region. Sagittal tomography of the skull showed normal-sized sella turcica. Endocrinological tests were almost within normal range. The tumor was totally removed by combined right subfrontal and interhemispheric approach. At the time of the operation, we confirmed that the tumor did not continue to the pituitary gland and that the diaphragma sellae was intact. Histological diagnosis of the tumor specimen was pituitary adenoma. Post-operative MRI showed a normal pituitary gland, thus supporting the diagnosis of ectopic pituitary adenoma. To our knowledge, only ten cases of suprasellar ectopic pituitary adenoma have been reported, including our case. Pathogenesis of ectopic pituitary adenoma was briefly discussed.

Adenoma↗
PubMed1993

Lectin histochemistry of normal and neoplastic peripheral nerve sheath. 1. Lectin binding pattern of normal peripheral nerve in man.

The binding patterns of lectins to normal peripheral nerves were examined. Twelve biotinylated lectins were used in this study; Canavalia ensiformis (Con A), Pisum sativum (PSA), Lens culinaris (LCA), Ricinus communis 1 (RCA-1), Arachis hypogaea (PNA), Glycine max (SBA), Sophora japonica (SJA), Bandeiraea simplicifolia 1 (BSL-1), Triticum vulgaris (WGA), succinylated WGA (s-WGA), Ulex europaeus 1 (UEA-1) and Helix pomatia (HPA). Cytoplasm of Schwann cells and perineurial cells was stained by Con A, PSA, LCA, s-WGA and WGA. PNA showed specific binding to perineurial cells, while after neuraminidase treatment stain with this lectin was demonstrated also in Schwann cells. Myelin sheaths were stained with fewer lectins. SBA and HPA with sialic acid removal rarely showed reactivity to the peripheral nerve structure in surgical specimens, in contrast to clear staining of Schwann cells, perineurial cells and myelin sheaths in autopsy specimens. The present study shows distinct lectin stainings of specific structures of the normal human peripheral nerves, and provides important basic information on the alterations of lectin binding patterns during pathological processes in the peripheral nerves.

Biotin↗
PubMed1993

Lectin histochemistry of normal and neoplastic peripheral nerve sheath. 2. Lectin binding patterns of schwannoma and neurofibroma.

Lectin binding patterns of 31 schwannomas and 6 neurofibromas were examined using 12 lectins, and the results were compared with those of normal peripheral nerves. Tumors obtained from 10 cases of neurofibromatosis and 4 recurrent schwannomas were included. Changes of glycoconjugates were observed in association with a neoplastic transformation of Schwann cells; Arachis hypogaea (PNA) staining after neuraminidase treatment seen in normal Schwann cells was reduced in schwannoma of Antoni type A, and bindings with Glycine max (SBA) and Helix pomatia (HPA) after sialic acid removal, which were not seen in normal Schwann cells, appeared in schwannoma cells. Intensities of staining of tumor cells with each lectin were higher in Antoni type B than those in Antoni type A. No differences in lectin binding patterns were observed between schwannomas in patients with neurofibromatosis or recurrent schwannomas and ordinary, primary schwannomas in patients without stigmata of neurofibromatosis. Lectin binding patterns of Schwann cells and perineurial cells in neurofibroma were almost similar to those in normal peripheral nerves with an exception of faint stain of Schwann cells with HPA after neuraminidase pretreatment. This result suggests differences in extent of differentiation between schwannoma cells and neoplastic Schwann cells in neurofibroma. Specific PNA binding to perineurial cells in neurofibroma indicates the significance of this lectin as a marker of these cells.

Glycoconjugates↗
PubMed1993

Solitary intracranial chondroma of the convexity dura: case report.

We present a rare case of chondroma originated from the dura mater of the cerebral convexity in a 16-year-old girl. Radiologic findings are reported with emphasis on computed tomography and magnetic resonance imaging scans, and histogenesis is briefly discussed.

Adolescent↗
PubMed1993

Multiple sinus pericranii with systemic angiomas: case report.

The authors report the case of an adult male who had multiple sinus pericranii, as well as angiomas in the retina and the skin of the knee. Although sinus pericranii is well documented, a simultaneous involvement in as many as four separate regions has not been reported. Clinical, radiographic, and histopathological features are detailed. Implications for the role of surgery and management is discussed.

Adult↗
PubMed1993

[Dermoid cyst in the fourth ventricle associated with Klippel-Feil syndrome].

Dermoid cysts in the central nervous system are often associated with various congenital disorders, especially dermal sinus and spina bifida. We report a case of dermoid cyst in the fourth ventricle associated with Klippel-Feil syndrome. A 47-year-old man with a long history of headache had been known to have a cystic lesion in the posterior fossa for 12 years. When he was referred to our hospital with complaints of transient tetraparesis, he showed bilateral cerebellar ataxia and minimal left hemiparesis. Furthermore, he was noted to have a webbed neck with a low hairline and facial asymmetry. CT and MRI showed multiple cerebral infarctions as well as a mass lesion in the posterior fossa. Cervical roentgenogram showed a fusion of C 2 and C 3 vertebrae. The tumor was totally removed via a suboccipital approach, and the diagnosis was a dermoid cyst. The present patient had not only dermoid cyst and Klippel-Feil syndrome but also hypertrophy of the zygomatic bone. The pathogenesis of the Klippel-Feil syndrome is presumed to be an intrauterine defect, with a failure of segmentation of mesodermal somites. The zygomatic bone is also derived from the mesoderm somites at early fourth week, too. From these points of view, the disturbance in the mesoderm before the fourth week of gestation might have played an important role in causing a dermoid cyst.

Cerebral Ventricle Neoplasms↗
PubMed1993

Lectin histochemistry of dermoid and epidermoid cysts of the central nervous system.

The binding affinities of seven lectins to four epidermoid and three dermoid cysts were studied and the results were compared with the epidermis and the oral mucosa. The reactivity of four epidermoid cysts of the fourth ventricle and the frontal lobe, and one dermoid cyst in the sylvian fissure was consistent with that of the skin, whereas the binding profile of one parasellar dermoid cyst was identical to that of the keratinized oral mucosa. Another parasellar dermoid cyst also showed close similarity to the buccal mucosa. These results indicate that cells of these cysts develop same glycoconjugates as do normal epithelial cells, and some of these cysts around the sellar region might be derived from the cells of the oral mucosa.

Adolescent↗
PubMed1993

[Central nervous system metastasis from lingual carcinoma: report of a case].

A rare case of lingual carcinoma which metastasized to the brain is reported. A 66-year-old man was referred to our department on April 23, 1991, with complaints of memory disturbance and mild left motor weakness of one month's duration. The patient had been discharged from the Department of Otolaryngology of our hospital 9 months before, after undergoing radical neck dissection and chemotherapy (THP, CDDP, PEP) for his lingual cancer with metastases to the cervical lymph nodes and the lung. On admission to our department, the patient complained of mild frontalgia. Neurological examination showed memory disturbance, change of character, mild left hemiparesis and urinary incontinence. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed a well circumscribed mass in the right frontal lobe associated with midline shift toward the left. Systemic Gallium-67 scintigraphy demonstrated an abnormal uptake in the right frontal region, but no abnormal uptake was seen in the neck and the lung. The most likely diagnosis was thought to be metastasis of lingual cancer. The patient underwent tumor removal 10 days after admission. A histological examination of the tumor specimen revealed metastatic anaplastic cell carcinoma, indicating a metastasis from lingual carcinoma. After postoperative radiotherapy (total 60 Gy), the patient was discharged without neurological deficit. Central nervous system metastasis from lingual carcinoma is quite rare. To the best of our knowledge, only two such cases have been reported. We report another rare case of solitary brain metastasis from lingual carcinoma and review the pertinent medical literature.

Aged↗
PubMed1993

[Creutzfeldt-Jakob disease transmitted by cadaveric dural graft: a case report].

We report a case of Creutzfeldt-Jakob disease in a 38-year-old man, transmitted by a cadaveric dural graft. In August 1985, he underwent cranial nerve decompression for hemifacial spasm and received a cadaveric dural graft for dural closure. He had been well until he began to complain of blurred vision and headache in May, 1990. He developed dementia, myoclonus and urinary incontinence over the subsequent 3 months. He was admitted to our hospital in August, 1990. On admission, he was somnolent and showed gait disturbance, myoclonus in extremities and elevated deep tendon reflexes symmetrically. The results of analysis of blood, urinary and cerebrospinal fluid were normal. The initial computed tomography (CT) and magnetic resonance imaging detected no abnormality. Electroencephalography showed typical periodic synchronous discharge (PSD). There was progressive worsening of his neurological symptoms, and this developed into mutism in September, 1990. CT, 11 months after clinical onset, showed marked enlargement of the ventricles and the sulci. In view of his rapid worsening clinical course, PSD findings on electroencephalography, and delayed progressive changes of CT findings, the diagnosis of CJD disease was made. The cadaveric dural graft was suspected as the cause of the patient's condition. Since Thadani et al reported the first case of CJD transmitted by cadaveric dural graft in 1988, 3 other cases have been reported. This is most likely the 5th reported case of Creutzfeldt-Jakob disease transmitted by cadaveric dural graft.

Adult↗