Biomedical subjects

O Kubo

Publications and source records attributed to O Kubo.

At least 55 records · Page 3Linked to original sources

PubMed1996

Pleomorphic xanthoastrocytoma with neurofibromatosis type 1: case report.

The authors report a case of pleomorphic xanthoastrocytoma (PXA) with neurofibromatosis type 1 (NF-1). A 21-year-old woman, noted to have had a number of café au lait spots since birth, presented with the chief complaint of headache. Neuroradiological studies revealed a cystic tumor of the left parietal lobe. Surgical treatment was performed. The tumor was located on the surface of the parietal lobe with the formation of cysts. Light, electron microscopic, and immunohistochemical examination showed the characteristics of typical PXA. This is the second reported case of NF-1 associated with PXA.

Adult↗

PubMed1996

Correlation between MR image characteristics and histological features of acoustic schwannoma.

We retrospectively studied 21 cases of histologically proven acoustic shwannomas with an emphasis on the correlation of their magnetic resonance imaging (MRI) findings and histological features. All cases were of low signal intensity in the T1W MRI. In the T2W MRI, 9 of them were of homogeneous high signal intensity (Hom-HSI-T2) and 12 of them were of heterogeneous high signal intensity (Het-HSI-T2). The cases of Hom-HSI-T2 were generally associated with capsular enhancement, and were usually cystic tumors with high vascularities and mainly Antoni A tissues. On the contrary, the cases of Het-HSI-T2 were generally associated with homogeneous enhancement, and were usually solid tumors with low vascularities and various tissue components.

Adult↗

PubMed1995

Management of intracranial hemorrhage associated with anticoagulant therapy.

BACKGROUND: Intracranial hemorrhage may be a particularly devastating complication of anticoagulant therapy. Very few accounts have reported data on the duration of anticoagulant discontinuation following intracranial hemorrhage or the intensity of anticoagulation during treatment for it, although we must adequately manage such a complication. METHODS: We analyzed the management of warfarin-related intracranial hemorrhages in 27 patients with cardiac diseases. We evaluated the degree of anticoagulation using the thrombotest. Anticoagulants were stopped as soon as the diagnosis of intracranial hemorrhage was established by computed tomographic scan. RESULTS: Mechanical valve prosthesis patients, who required intensive long-term anticoagulant therapy, constituted the majority of our series (74.1%). Intraoperative hemostasis was brought under control despite low thrombotest values (13%-68%) at the time of surgery except for the acute subdural hematoma (SDH) patients with cerebral contusion. Early resumption of anticoagulant therapy (within 3 days) did not cause intracranial rebleeding in any operative patient. All the chronic SDH patients and some of the subcortical hematoma patients had a good outcome. All three patients with acute SDH and contusion, however, had a fatal outcome because of intracranial rebleeding within a short period of time or ineffective intraoperative hemostasis. CONCLUSIONS: The patients with anticoagulant-related intracranial hemorrhage may undergo surgery with thrombotest values approximately between 20% and 60%, and anticoagulants can be resumed after an interval of 3 days. Aggressive surgery should particularly be performed in patients with anticoagulation-related chronic SDH or subcortical hemorrhage, as in the cases of anticoagulant-unrelated intracranial hemorrhage.

Adolescent↗

PubMed1995

Inhibin alpha, beta A subunit and activin type II receptor mRNAs are expressed in human brain tumors.

Inhibin and activin were initially isolated as regulators of pituitary or gonadal hormone and are now known to be growth factors belonging to the TGF-beta family with diverse influences on the differentiation and proliferation of various tissues. To investigate the role of inhibin and activin in human brain tumors, the expression of inhibin alpha, and beta A mRNA as well as activin type II receptor (ACTR II) mRNA were studied in various human brain tumors. The tumors were divided into the following 4 groups: 3 Rathke's cleft cysts and 2 craniopharyngiomas (group 1), 8 meningiomas (group 2), 8 malignant gliomas (group 3), and various other tumors including 1 each of germinoma, astrocytoma, hemangioblastoma, and osteochondroma as well as 2 malignant lymphomas and 2 metastatic squamous cell carcinomas (group 4). Immediately after resection, tumor tissues were homogenized in guanidine thyiocyanate to extract total RNA. PCR was then performed with reverse-transcribed cDNA and the respective amplification primers. DNA bands were obtained by agarose gel electrophoresis. Messenger RNA for the inhibin beta A subunit was demonstrated in all of the tissues studied. In contrast, inhibin alpha subunit mRNA was expressed in 60%, 50%, 75%, and 75% of the tumors in groups 1, 2, 3 and 4, respectively, whereas ACTR II mRNA was demonstrated in 20%, 37.5%, 62.5% and 50% of the tumors in each group. Coexpression of mRNAs for the inhibin alpha, and beta A subunits and ACTR II occurred in some brain tumors. The levels of inhibin alpha and ACTR II mRNA tended to be higher in the tumors with a higher grade of malignancy.(ABSTRACT TRUNCATED AT 250 WORDS)

Activin Receptors↗

PubMed1995

Growth rate of intracranial meningioma: tumor doubling time and proliferating cell nuclear antigen staining index.

The relationship between tumor doubling time, estimated by serial computed tomography (CT), and the proliferating cell nuclear antigen (PCNA) staining index of the tumor specimen was analyzed in 12 patients with nine partially or subtotally resected meningiomas and three meningiomas which recurred after gross total removal. There were nine meningothelial and three fibrous meningiomas. Malignant meningiomas and hemangiopericytomas were excluded. Serial CT was performed at various intervals ranging from 354 to 2007 days. Formalin-fixed, paraffin-embedded archival tissues were immunohistochemically stained using the avidin-biotin complex method with monoclonal antibody against PCNA. Percentages of PCNA-positive cells were calculated in 10 microscopic fields to determine the mean PCNA staining index. PCNA staining indexes varied from 0.13% to 7.46%. The tumor doubling time ranged from 197 to 7943 days and demonstrated a significant inverse rank correlation with the PCNA staining index (r = -0.89, p = 0.003). Meningiomas with PCNA staining indexes higher than 1% have comparatively short tumor doubling times of less than 5 years. PCNA immunostaining is a useful method for evaluating the proliferative activity of meningiomas.

Biomarkers, Tumor↗

PubMed1995

[A case of astrocytoma of corpus callosum presented diagnostic dyspraxia].

A case of astrocytoma whose first clinical presentation was diagnostic dyspraxia was reported. A 38-year-old right-handed male experienced funny motion of his left hand triggered by voluntary movement of his right hand. One day, he tried to insert a coin into the vending machine with his right hand, then the left hand was against the other. One month after that event, he experienced headache and vertigo. On admission, there were no abnormal findings on neurological examination. On neuropsychological examination, he was cooperative, well orientated and attentive, and there were no callosal disconnection symptoms. Frontal lobe function tests were slightly impaired. T1-weighted MRI demonstrated irregular mixed signal intensity mass lesion extending from the genu to the body of the corpus callosum and the cingulate gyrus. This lesion was slightly enhanced with Gd-DTPA. Biopsy was performed and histological diagnosis was fibrillary astrocytoma. After irradiation and chemotherapy, he was discharged from the hospital without evident neurological deficit. About 20 cases of diagnostic dyspraxia have been reported and almost all of them were caused by cerebro-vascular disease. This is the first case of brain tumor who presented diagnostic dyspraxia.

Adult↗

PubMed1995

Immunohistochemical and electron microscopic study of subependymal giant cell astrocytoma.

Six cases of subependymal giant cell astrocytoma (SGCA), five associated with tuberous sclerosis (TS), were reviewed by light microscopy, electron microscopy and immunohistochemistry. Histologically, all cases showed features typical of SGCA. GFAP and neurofilament expression were found in all cases. Synaptophysin and myelin basic protein were positive in single different cases. The MIB-1 positive rate was 0% in 4 cases, 3% in a case with recurrence after a partial resection, and 6.4% in another case with a rapid growing tumor. By electron microscope, glial filament was identified in the tumor cells of all cases, whereas none of them showed any ultrastructural evidence of a neuronal origin. We therefore suggest that SGCA is a glial origin tumor, arising from the astrocytic part of a subependymal nodule--the most common cerebral lesion of tuberous sclerosis caused by distorted migration of the germinal mantle-the neuronal part of which remains as entrapped remnants of dysgenetic, incompletely expressed neuronal cells.

Adolescent↗

PubMed1994

Peritumoral brain edema and cortical damage by meningioma.

Forty supratentorial meningiomas were analyzed to identify factors causing peritumoral brain edema. Parasagittal, sphenoid ridge, and olfactory groove meningiomas induced edema more frequently than those in other locations. Meningothelial meningiomas were more invasive than other types and were associated with more peritumoral edema. Brain edema correlated significantly with tumor size and histological evidence of leptomeningeal and cortical damage from the tumor. Larger tumors destroy the leptomeninges and cerebral cortex, allowing direct transmission of edema fluid into the white matter, resulting in vasogenic edema.

Adult↗

PubMed1994

Meningiomas associated with peritumoural venous stasis: three types on cerebral angiogram.

Many factors have been suggested as possible mechanisms for the development of peritumoural oedema in meningioma. Venous compression by the tumor is thought to be one factor, but reports presenting a direct relationship between venous compression and the formation of oedema are rare. We have recently observed 6 meningioma patients in whom venous stasis contributed to peritumoural oedema. The stasis was due to 1) compression of an adjacent cortical vein by the tumour with stasis at the site of compression and/or its distal portion, 2) compression of adjacent brain by the tumour with prolonged perfusion and delayed venous return (visualized as pial staining in the capillary and venous phases), and 3) presence of an early draining vein linked to a nearby cortical vein with stasis at its periphery. Venous compression and stasis seem to be related not only to the formation of peritumoral oedema but also to the occurrence of haemorrhagic infarction after the resection of meningiomas.

Adult↗

PubMed1994

Meningioma associated with chronic subdural hematoma and meningothelial cell cluster within the hematoma capsule--case report.

A 47-year-old female presented with an unusual association of convexity meningioma with chronic subdural hematoma, manifesting as headache and left hemiparesis 10 days before admission. Computed tomography showed an isodense right frontal tumor with significant enhancement postcontrast and a hypodense subdural hematoma in the right frontotemporal area. Craniotomy exposed an extracerebral tumor facing a liquefied subdural hematoma encapsulated by outer and inner membranes. The hematoma was evacuated and the tumor was totally removed. Histological examination revealed a meningothelial meningioma with hemangiopericytic components. Microscopic examination of the hematoma capsule revealed a cluster of meningothelial cells in the outer membrane.

Brain Neoplasms↗

PubMed1994

Magnetic resonance imaging and quantitative analysis of contents of epidermoid and dermoid cysts.

The intracapsular cholesterol, protein, and calcium contents of epidermoid and dermoid cysts from seven patients were compared with the signal intensities on T1-weighted spin-echo magnetic resonance (MR) images. All specimens had a paste-like consistency when resected. Epidermoid and dermoid cysts demonstrated a wide range of cholesterol and calcium contents, and epidermoid cysts were not always rich in cholesterol. Five patients had cysts with lower signal intensity than white matter, which contained more than 18.3 mg/g wet weight of protein. One of these patients had the highest cholesterol content of all seven patients (22.25 mg/g wet weight) and another had the highest calcium content (0.75 mg/g wet weight). Two patients had cysts with higher signal intensity than white matter, with protein contents of lower than 4.3 mg/g wet weight. High protein content (> 18.3 mg/g wet weight) may decrease signal intensity on T1-weighted MR images, while low protein content (< 4.3 mg/g wet weight) may increase signal intensity in epidermoid and dermoid cysts with high viscosity (paste-like consistency) contents.

Adolescent↗

PubMed1994

Clinico-pathological study of malignant lymphoma of the central nervous system.

This report describes the clinico-pathological features of a group of 36 patients with malignant lymphoma of the central nervous system (CNS) who were treated at one institution between 1970 and 1993. All cases were B cell type lymphomas. The authors summarize the most salient findings with respect to clinical course, pathology, treatment and disease outcome, and emphasize the value of diagnostic and therapeutic modalities in the management of patients with primary CNS lymphoma.

Adolescent↗

PubMed1994

[Treatment of malignant brain tumor].

The pathophysiology and treatment of malignant brain tumors (malignant glioma, metastatic brain tumor and malignant lymphoma) were discussed. In order to improve the prognosis of malignant brain tumor patients, many clinical trials have been conducted. The most acceptable treatment for malignant glioma is surgical resection plus radiochemotherapy with ACNU. A multidisciplinary approach to treatment is important for control of metastatic brain tumors. Treatment of malignant lymphoma includes radiotherapy and chemotherapy in combination. Combination chemotherapy with CHOP is more effective for malignant lymphoma.

Brain Neoplasms↗

PubMed1993

Recurrence of symptomatic Rathke's cleft cyst: a case report.

A 65-year-old man presented with bitemporal hemianopsia. He had undergone frontal craniotomy for a Rathke's cleft cyst associated with narrowed visual field 8 years earlier. His vision had returned to normal soon after surgery and he remained asymptomatic until the present complaint. Neurodiagnostic imaging revealed a recurrence of the intrasellar cyst extending into the suprasellar cistern. His vision improved rapidly after a second surgery. The histological findings were the same as those of the previous operation; the cyst wall was composed of a single layer of ciliated columnar epithelium resting on a collagenous connective tissue stroma.

Aged↗

PubMed1993

Immunohistochemical detection of carbohydrate determinant 19-9 (CA 19-9) in intracranial epidermoid and dermoid cysts.

We evaluated carbohydrate antigen (CA) 19-9 levels of intracranial dermoid and epidermoid cyst in serum and intratumoral tissue. The preoperative serum levels were mildly to moderately higher than their normal ranges in four of seven patients. In four patients with high serum CA 19-9 levels, they returned to normal ranges in three who had the cyst resected totally and remained slightly high in one with residual cyst. Immunohistochemical studies using anti-CA 19-9 antibody demonstrated positively stained capsule and keratinous tissue. Serum CA 19-9 levels of intracranial dermoid or epidermoid cysts with more teratomatous components may be elevated above normal levels.

Adolescent↗

PubMed1993

Immunohistochemical study of craniopharyngiomas.

The purpose of this study is to present the histological characteristics of tumor origin and proliferative characteristics of craniopharyngioma. In 25 craniopharyngiomas, the immunoperoxidase technique revealed strong positive reactions for keratin and cytokeratin in cytoplasm of tumor cells. But, immunostaining of keratin and cytokeratin differ from each of layer of craniopharyngioma. The ciliated epithelium in the craniopharyngioma was not stained by keratin, but ciliated epithelium of Rathke's cleft cyst was stained by cytokeratin.

Antigens, Neoplasm↗

PubMed1993

[Two cases of giant aneurysms arising from the distal segment of the anterior cerebral circulation].

Giant aneurysm arising from the distal segment of the anterior cerebral circulation is extremely rare, and only 14 cases of anterior cerebral circulation aneurysms have been reported in the literature. This report describes two cases of giant intracranial aneurysms, one arising from the distal segment of the middle cerebral artery, and the other from the azygos anterior cerebral artery. Although both of the patients started with intracranial hemorrhage, their surgical outcomes were good. The growth mechanisms of each aneurysm are discussed based on the clinical and pathological findings. Since the wall of the middle cerebral artery aneurysm showed granulomatous changes with infiltration of many inflammatory cells, the aneurysmal enlargement is considered to have resulted from chronic inflammation of the wall. In the case of anterior cerebral artery aneurysm, hemodynamic stress through the azygos artery may have caused the giant aneurysm. Operative indication for giant intracranial aneurysm is controversial. Since the surgical outcomes of reported cases are definitely better than those of the patients with proximal giant aneurysm, we conclude that giant aneurysm arising from the distal segment of the cerebral artery should be treated surgically.

Adult↗

PubMed1993

[A case of cavernous angioma--usefulness of magnetic resonance imaging and magnetic resonance angiography in diagnosis].

We reported a case of cavernous angioma in the middle cranial fossa, which was diagnosed with magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA). The patient was a 56-year-old female, who presented with sudden onset right-sided headache with nausea. Her neurological findings were normal. On CT scan a high density area with a surrounding thin low density area was shown in the right posterior temporal region without contrast enhancement. Cerebral angiography of the left vertebral artery revealed only a small stain at the end of the right posterior temporal artery. On T2-weighted MRI after one month, the same region exhibited a central area of mixed signal intensities surrounded by a rim of decreased signal. MRA showed an area with remarkable 10mm mass with some contiguous vessels in the right posterior temporal region. That mass was resected operatively. It's pathological diagnosis was cavernous angioma. For diagnose of cavernous angioma, MRI and MRA were very useful. The specificity of these methods are superior to better than CT or angiography.

Brain Neoplasms↗