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Biomedical subjects

I Shibata

Publications and source records attributed to I Shibata.

At least 73 records · Page 4Linked to original sources
PubMed1990

Analysis of properties of monoclonal antibodies to transmissible gastroenteritis virus using TO-163 strain.

Nineteen monoclonal antibodies (MAbs), reactive in enzyme-linked immunosorbent assay (ELISA), with porcine transmissible gastroenteritis (TGE) virus TO-163 were obtained. Of these MAbs, 5 showed neutralizing (NT) activity (x 3,200 to 25,600) against TO-163. One of the MAbs which had NT activity showed hemagglutination inhibition activity (x 5,120) too. 14 hybridomas of polypeptide specificity against TO-163 strain were developed from which 11, 2, and 1 were specific for protein E2, N, and E1, respectively. Immunofluorescence staining patterns in TGE virus-infected cells reacted with MAbs were divided into three groups (types I, II and III). The fluorescence staining of E2 specific MAbs having NT activity were limited to the perinuclear area. All MAbs having NT activity showed the same fluorescence staining pattern.

Animals↗
PubMed1990

[Super conductive MR imaging of small acoustic tumor].

Eight patients with acoustic tumor were studied with a superconductive MR imaging. T1-weighted images with Gd-DTPA most accurately showed the margin of the seventh and eighth nerves in the internal auditory canal and were most sensitive in detecting small tumors. T2-weighted images were inferior to T1-weighted images, that could fail to detect small tumors. High resolution, thin slice, MR imaging using surface coil is particularly useful for small acoustic tumor because of its higher specificity compared with air-CT, cisternography.

Adult↗
PubMed1989

[Magnetic resonance imaging in 38 cases of acoustic tumors].

The value of magnetic resonance imaging (MRI) in the diagnosis of acoustic tumors was retrospectively assessed in 38 cases. A 0.15 Tesla permanent magnet and a 1.5 Tesla superconducting magnet were employed in 24 and 14 cases, respectively. Gadolinium diethylene triamine pentaacetic acid (Gd-DTPA), a paramagnetic contrast agent, was used in 10 cases. Acoustic tumors were identified in all cases. Small, medium, and large tumors were depicted with equal clarity by MRI and computed tomography (CT). However, tumor contour and extension, accompanying cysts, and brainstem displacement were more clearly visualized on MRI. The use of Gd-DTPA improved the quality of the MR images by markedly enhancing the acoustic tumors in all cases. In particular, detection of small acoustic tumors and intra- or paratumoral cysts was facilitated by the use of Gd-DTPA. The possibility of a correlation between acoustic tumor histology and MRI features was studied by calculation of the contrast to noise (C/N) ratio in 10 cases of acoustic tumor and 7 cases of meningioma. No definite correlation was demonstrated, but there appeared to be some difference in the C/N ratio between acoustic tumors and meningiomas. In three volunteers, MRI demonstrated intracanalicular nerves, separately. Because of its higher resolution, MRI can be expected to replace CT and air CT in the diagnosis of acoustic tumors.

Adult↗
PubMed1989

[The correlation of host-immunocompetence and host-humoral states to the take incidence and proliferative activity of implantation C-6 glioma cells].

Recently it has become evident that "second growth factor" of growth hormone (GH), such as somatomedins, has an effect on the proliferation and growth of tumor cells derived from nervous tissue. Effects of host-immunocompetence and the host-humoral states on the take incidence and proliferative activity of brain tumor cells were studied using two animal models: nude mouse and pituitary Snell dwarf mouse. Nude mouse is known to be immunodeficient. Pituitary Snell dwarf mouse is characterized by lack of circulating GH, TSH, prolactin, in addition to immunodeficiency. Cell line used in this experiment was C-6 cell of rat glioma cell. After intracranial implantation of C-6 glioma cells in the animals, the take incidence and growth rate of C-6 glioma cells were followed up and measured over a period of 2 months. Tissues of implants were studied immunohistochemically and biochemically. Regardless of cell line, successful take incidence in the different animal species was found to be greater in the descending order of nude mouse, dwarf mouse. This confirmed the role of immune status for the successful take of iso-, or heterologous tumor cells after implantation. We are now investigating the effect of exogenous GH on the growth rate of cells implanted in the dwarf mouse. This may clarify the effect of growth factors on proliferative activity of implanted tumor cells.

Animals↗
PubMed1986

[A case of intracranial hypoglossal neurinoma].

A case of intracranial hypoglossal neurinoma is reported. A 32-year-old man with a history of unsteady gait and headache for one and a half years was admitted to our hospital on September 23, 1983. Neurological findings on admission were nystagmus toward the left, left IXth and Xth cranial nerve paresis, left cerebellar signs, paresthesia of the left upper and lower extremities on neck flexion, and left pyramidal signs. Atrophy or fasciculation of the tongue was not noted. Computed tomography demonstrated a large isodensity and partially low density mass in the posterior fossa which was markedly enhanced and sharply margined with contrast medium. The tumor extended 45 mm over the edge of the foramen magnum. The maximum size was 45 mm X 40 mm. The coronal and sagittal reconstruction CT scan clearly demonstrated the attachment and extension of the tumor. Enlargement of the hypoglossal canal was clarified by changing the window level, window width and using 2 mm slice CT scan. Anterior-posterior x-ray view of the skull tomography showed enlargement of the hypoglossal canal, as indicated by the CT scan. The left hypoglossal canal was 7 mm and right was 3 mm in diameter. Vertebral angiography demonstrated that the tumor was located in the left posterior fossa, but no tumor stain appeared. This patient did not have XIIth cranial nerve palsy, but the neuroradiological findings strongly suggested a hypoglossal neurinoma, especially the findings of the CT scan and the anterior-posterior x-ray view of the skull tomography. On October 5, suboccipital craniotomy with Cl laminectomy was performed in prone position.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

[A case of giant cell tumor of the sphenoid bone--special emphasis on its clinico-radiological features and radiosensitivity].

A 19-year-old man was admitted to the hospital because of blurred vision, visual field defect, diplopia and hypesthesia of the left face. Neurological examination on admission revealed impairments of the II, III, IV, VI cranial nerves bilaterally and the first branch of the V nerve on the left. X-ray films of the skull showed a marked decalcification of the sella and upper portion of the clivus. Cerebral angiography demonstrated a moderately vascularized, large tumor in the sella-clival region. The tumor was supplied mainly by the branches of the right internal carotid artery, which was occluded at the cavernous portion. CT scans showed a large, oval mass located at the mid-portion of the anterior and middle fossa. Hounsfield number of the tumor was approximately 64.0, but several high density spots, probably due to destroyed bone fragments, were seen inside. The tumor was markedly enhanced with contrast medium. Three successive craniotomies were carried out through right fronto-temporal approaches, but total removal of the tumor was not achieved. Histological examination of surgical specimens disclosed that the tumor was consisted of abundant multinucleated giant cells and fewer spindle shaped stromal cells. Postoperative radiotherapy by telecobalt was tried and a total dose of 70Gy was delivered to the residual tumor. Effect of radiotherapy was remarkable and the size of the tumor on CT was markedly reduced to the extent of 10% of the pre-radiation tumor size. The patient was discharged in a good condition and there have been no signs of recurrence for 10 months so far. On the basis of our case and cases reported in the literature so far, the authors discussed clinical and radiological features, difficulty in surgical treatment and radiosensitivity of giant cell tumor of the sphenoid bone.

Adult↗
PubMed1984

[A case of subependymoma in the lateral ventricle with intraventricular hemorrhage].

Subarachnoid hemorrhage attributable to brain tumor, particularly due to benign tumor, is not common. A case of subependymoma in the lateral ventricle, which manifested itself with an episode of subarachnoid hemorrhage was reported. A 33-year-old woman was admitted to our hospital because of severe headache and transient loss of consciousness, but neurological examination revealed no abnormality except for slight disturbance of consciousness and nuchal rigidity. Lumbar puncture showed an opening pressure over 350mmH2O and grossly bloody CSF. CT scan revealed an enhanced mass occupying the left ventricular trigone. Angiography, however, demonstrated no tumor stain or other vascular abnormality. Preoperative diagnosis was an intraventricular tumor of benign nature. A soft tumor arose from the lateral wall of the trigone was removed subtotally by paramedian parieto-occipital approach. Histology of the tumor was of typical subependymoma with scanty vascularity. Intraventricular or subarachnoid hemorrhage from cerebral neoplasm reported so far, is mostly due to a highly vascularized tumor. Subependymoma is of benign nature with poor vascularity, and therefore, intraventricular hemorrhage from the subependymoma was rarely reported in the literature. On the basis of the findings of angiography, serial CT scans and histological examination, it is reasonable to assume that intraventricular bleeding in our case is not attributed to the tumor per se, but to tearing of subependymal or ependymal veins extremely extended by the tumor growth.

Adult↗
PubMed1983

[Disproportionately large communicating fourth ventricle--report of 2 cases].

A term of 'disproportionately large, communicating fourth ventricle' (DLCFV) was first proposed by in Harwood-Nash in 1980. It is somewhat different from the well known clinical entity of 'isolated or trapped fourth ventricle', because of apparent patency of aqueductal canal. Two cases of typical DLCFV encountered in our clinic were described. First patient was a 24 year old man in whom this condition developed following operations for lumber disc and second patient was 22 year old woman in whom the disease developed after subarachnoid hemorrhage. In both cases, main symptoms were attributable to hydrocephalus but three posterior fossa symptoms, nystagmus, Parinaud' sign and truncal ataxia were also characteristic. On the CT scan, the fourth ventricle was extraordinarily enlarged. Patency of the aqueductal canal was demonstrated by air study or Conray and Metrizamide ventriculography. On the other hand, occlusion was demonstrated or highly suspected in or near the foramina Magendie and Luschka. After a routine ventriculo-peritoneal shunt operation, the fourth ventricle decreased in size and the symptoms were immediately relieved. Plausible explanation for mechanism involved in occurrence of DLCFV were (1) occlusion process in or near the fourth ventricle outlets seems to be crucial in this pathologic condition. Collision of CSF pulse waves against the obstruction may yield a water hammer effect on the fourth ventricle. (2) abnormal weakness of the brain stem parenchyma around the fourth ventricle to CSF pressure may be another contributory factor.

Adult↗
PubMed1983

[Chronic subdural hematoma associated with arachnoid cyst--study of the mechanism of its development].

A significant number of cases of chronic subdural hematoma associated with middle fossa arachnoid cyst has been reported in literature, but sufficiently tenable explanation for co-occurrence of both lesions has not yet proposed. In this study, authors try to elucidate mechanisms involved in development of chronic subdural hematoma and arachnoid cyst in the same patient. Eighteen cases with arachnoid cyst in the middle fossa were diagnosed by CT scan during last 5 years in our institute. Among these, five patients had chronic subdural hematoma additionally to their middle fossa arachnoid cyst. Analysis of clinical, roentgenological data and operative findings in our five cases and reviewing of cases reported so far in the literature makes clear the following characteristics in this pathological condition. 1) Patients of chronic subdural hematoma associated with arachnoid cyst were obviously younger than patients with usual chronic subdural hematoma. 2) Chronic subdural hematoma developed in the same side to the associated arachnoid cyst. 3) Characteristic changes in the skull on x-ray films indicated the long lasting existence of middle fossa arachnoid cyst. On the other hand, history of cases suggested that chronic subdural hematomas had developed within recent 1-3 months. 4) Intracranial pressure tended to remain normal or slightly elevate. 5) Abnormal, small veins which run on the surface of the membranous capsule of arachnoid cyst and bridge the Sylvian fissure were not infrequently found at operation. These veins were not able to visualized on routine angiography. On the basis of these clinical and pathological characteristics, authors infer a mechanism for development of subdural hematoma associated with arachnoid cyst. The presence of middle fossa arachnoid cyst must increase a compressibility of the intracranial content, especially of the ipsilateral cerebral hemisphere and it predisposes for development of chronic subdural hematoma.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1981

Hemagglutination of epizootic hemorrhagic disease virus.

Hemagglutination of epizootic hemorrhagic disease virus (EHDV) with a variety of erythrocyte species at 4 degrees C, room temperature and 37 degrees C was dependent on the NaCl molarity and the pH of the diluent. The hemagglutination inhibition test was used to identify EHDV serotypes.

Animals↗