T. Kamiryo

Nucleolar Organizer Regions in Meningioma

Seventy-eight cases of meningioma and related tumors were examined independently using a simple and reproducible argyrophilic method for the demonstration of nucleolar organizer regions (AgNORs) and staining with bromodeoxyuridine monoclonal antibody. The mean number of AgNORs per cell and the bromodeoxyuridine labeling index were shown to be linearly related (r = 0.84, P less than 0.001). The mean AgNOR number was 2.99 for meningeal sarcoma, 2.29 for anaplastic meningioma, 2.08 for hemangiopericytic meningioma. 1.72 for recurrent meningioma without atypical histological findings, and 1.52 for nonrecurrent meningioma. We noted that the mean number of AgNORs reflected the cellular kinetics of a tumor and was related to histological grade and clinical behavior.

Prognostic implications of meningiomas in the elderly (over 70 years old) in the era of magnetic resonance imaging.

SummaryDuring the 5 years from 1987 to 1991, 89 elderly patients, aged 70 years and over, were admitted to departments of neurosurgery in Yamaguchi prefecture with meningioma. The clinical features and prognostic implications of meningioma in the elderly were assessed retrospectively. Seventy-eight (88%) of the 89 patients underwent surgery, which was a higher rate than has been previously reported. The length of clinical history was also shorter than in previous studies, and was partly due to the recent introduction of magnetic resonance imaging (MRI). The incidence of poor prognosis (severe disability, vegetative or dead) in the elderly and a younger group aged less than 70 years was 13% and 7%, respectively, but the difference was not statistically significant. In the surgically treated elderly group, age did not influence the patients outcome. The factors affecting the outcome were pre-operative neurological deficit (p<0.05), histological malignancy (p<0.05), and multiple operations (p<0.05). Twenty-seven of the elderly meningioma patients were in good physical condition with minimal neurological involvement. They underwent total removal of the tumour at the first operation, and the histological diagnosis was benign. Twenty-five of these 27 patients fell into the best outcome category. Therefore, age alone was not a factor preventing proper surgical treatment of meningioma in the elderly.

Intracranial pressure monitoring using a programmable pressure valve and a telemetric intracranial pressure sensor in a case of slit ventricle syndrome after multiple shunt revisions

A case of hydrocephalus showing slit ventricle syndrome after multiple shunt revisions was treated with a programmable pressure valve, and intracranial pressure was monitored with a telemetric sensor. High pressure setting produced positive and normal values of intracranial pressure in this patient. We report our experiences.

Transferrin receptors in injured brain

SummaryRecent studies have demonstrated the presence of transferrin receptors (Tf-R) in the central nervous system. The present study of Wistar rats with experimentally induced brain injuries, using immunohistochemistry at the light microscopy level, demonstrated the presence of Tf-R in regenerated endothelial cells, reactive astrocytes and in other cells, probably macrophages. Although Tf-R were seen in proliferating cells, Tf-R were also observed in nonproliferating cells, many of them macrophages. The receptors perhaps bind transferrin in edema fluid and play an important role in lesion repair.

Glial fibrillary acidic protein (GFAP) expression and nucleolar organizer regions (NORs) in human gliomas.

The frequency of nucleolar organizer regions (NORs) in each glioma tissue and the relation between the expression of glial fibrillary acidic protein (GFAP) and the frequency of NORs was investigated. The number of Ag-NORs per cell for glioblastoma multiforme was significantly higher than that for anaplastic astrocytoma (P less than 0.05) and that for astrocytoma (P less than 0.01). The number of Ag-NORs per cell for GFAP-positive cells was significantly lower than that for GFAP-negative cells in each histopathological grade (P less than 0.01). Moreover, the linear relationship was demonstrated between the Ag-NORs numbers of GFAP-negative cells and bromodeoxyuridine (BUdR) labeling indices. From these results, it is concluded that many GFAP-positive glioma cells may have low growth potential in glioma tissue and GFAP-negative cells may have a close relation to cell proliferation. The combination of immunohistochemical and silver colloid staining is a useful method for investigating the biological characteristics of brain tumors.

Major histocompatibility complex expression in brain of rats with graft-versus-host disease

In a healthy state, the central nervous system (CNS) is believed to be an immunologically privileged site, which does not participate in the immune reactions of the rest of the body, and in which identifiable components of the immune system are rare or non-existent. In this study, an immunohistochemical examination of the CNS of F1 hybrid rats following induction of graft-versus-host disease (GVHD) was carried out to determine whether specific immune reactions in the normal CNS could occur during a systemic immune reaction. The results revealed extensive parenchymal and vascular expression of class I and II major histocompatibility complex (MHC) encoded cell surface molecules. The strongest expressors of class I and II molecules were endothelial cells and parenchymal cells, respectively, the latter being apparently activated microglia, in the cerebrum and cerebellum of rats with GVHD. In addition, occasional scattered lymphocytes were detected in the CNS of GVHD rats without blood-brain barrier disruption. Thus, evidence was obtained for the presence of immune responses such as MHC antigen expression and lymphocyte infiltration in the CNS during a strong systemic immune response such as GVHD, microglia and endothelial cells apparently playing an important role.

The microvascular architecture of human malignant glioma

SummaryThe three-dimensional microvascular architecture of human glioma was investigated. The results of the study, the first of its kind, suggested that the process of vascularization in glioma is based on two patterns. In a large proportion of the glioma, one pattern is similar to the vascularization observed in normal developing fetal and newborn rat brain, while in a small proportion of the glioma, another pattern including complicated vascular protrusion and spiral running, is seen.

Cerebral endothelial regeneration following experimental brain injury

SummaryIt is still unknown when and in which area endothelial regeneration occurs after brain injury, and to what extent such changes depend on the severity of the injury. We have, therefore, studied bromodeoxyuridine (BrdU) uptake by regenerating endothelial cells in two different groups of rats given cold lesions using immunohistochemistry employing anti-BrdU monoclonal antibody, anti-factor VIII-related antigen antibody and anti-glial fibrillary acidic protein antibody. The earliest evidence for the presence of BrdU-positive endothelial cells (BrdU+end) was observed at 2 days after injury, the injured endothelial cells regenerating from the edge toward the center of the lesion in both groups. We considered that edema fluid could act as an important factor, since at 2 days post-injury BrdU+end were not in contact with macrophages and were always found in Evans blue-stained areas. Study of endothelial cell kinetics also confirmed that the repair of injured endothelial cells was intimately involved in the reconstruction of the blood-brain barrier, since the time of disappearance of BrdU+end coincided with the disappearance of Evans blue-stained areas. The difference in the process of endothelial regeneration was first apparent on the 3rd day, there being no difference at 2 days.

Bilateral intracranial fibrous xanthoma

We present a case of fibrous xanthoma in a 6-year-old boy who showed disturbance of consciousness and signs of increased intracranial pressure. A computed tomographic (CT) scan showed bitemporal enhanced masses and hydrocephalus. The patient was operated on in two stages. The tumors were located intradurally and extracerebrally and were firmly attached to the dura mater at the base of the middle fossa. Glial fibrillary acidic protein stain was negative, and histologic examination suggested a diagnosis of bilateral fibrous xanthoma. Postoperative CT scan showed residual tumors and an enlarged choroid plexus adjacent to it. A CT scan at 12 years of age showed no enhanced tumor, but disclosed bitemporal high-density areas and diffuse brain atrophy; the choroid plexus reverted to normal size. The patient showed mental and physical retardation, perhaps owing to the compression of the hypothalamus during early childhood. This would appear to be the first known case of bilateral intracranial fibrous xanthoma.

Cerebral Endothelial Regeneration Following Brain Injury

It has not been determined when and in which area regeneration of the cerebral endothelium occurs after brain injury (Orita et al. 1988). We therefore studied bromodeoxyuridine (BrdU) uptake by regenerating endothelial cells in two different groups of rats given cold lesions using immunohistochemistry employing anti-BrdU monoclonal antibody, anti-factor VIII-related antigen antibody and anti-glial fibrillary acidic protein antibody.