Evaluation of blood-brain barrier permeability and the effect of interferon in mouse glioma model.

The aim of this study was to evaluate whether interferon [IFN] can affect intracerebrally grown glioma and how alteration of the blood-brain barrier [BBB] may influence this effect. An intracerebrally implanted glioma G-26 (G-26) mouse brain-tumor model was developed and used in these studies. Histological characterization of this intracerebrally grown tumor revealed its anaplastic character. The astrocytic origin of G-26 was evidenced by glial fibrillary acidic protein staining and electron microscopic visualization of glial filaments. A study of tumor progression and animal survival showed development of a well defined tumor nodule within approximately seven days after the implantation. The median animal survival time was 27 +/- 3.8 days. The integrity of the blood-brain barrier [BBB] within the tumor was evaluated by the intravenous injection of horseradish peroxidase at days 3, 7, 10 and 20 after brain tumor implant and compared to 'sham' controls. The tumor-induced BBB alteration was progressive from day 3 to day 20. Glioma-26 subcutaneously passed in C57BL/6 mice was also continuously cultured in vitro. Its proliferation was inhibited by homologous mouse interferon alpha/beta [MuIFN alpha/beta] but not by human interferon alpha lymphoblastoid or human interferon beta. The in vivo studies of G-26 glioma treatment with MuIFN alpha/beta were performed using single bolus of IFN in osmotically altered animals or slow IFN infusion through osmotic micro-pumps. The slow infusion of IFN had no effect on animal survival. However, a statistically significant increase in animal survival was observed after single bolus IFN treatment following osmotic BBB alteration.

Extracranial manifestation of invasive pituitary adenoma.

An invasive pituitary adenoma caused nasal obstruction and marked visual loss due to compression of the optic chiasm. Surgical and medical treatment produced dramatic recovery of vision. Although the reason that certain prolactin-secreting adenomas behave in a locally aggressive fashion is unknown, the prognosis for invasive pituitary adenomas, in general, is relatively good.

Progressive necrotizing myelopathy associated with leukemia: clinical, pathologic, and MRI correlation.

We describe a patient with progressive, irreversible, necrotizing myelopathy associated with myelomonocytic leukemia. The neuropathologic lesions consisted of diffuse necrosis, most pronounced in the cervical cord and affecting both the gray and white matter. These areas corresponded to areas of increased T2 on magnetic resonance imaging scans of the patient. We felt that there was no causal relationship of these lesions to any single antileukemic agent the patient received, and no other local or systemic causes were found to explain the lesions at necropsy. It is suggested that our case is an example of paraneoplastic necrotizing myelopathy. To our knowledge, this is the third case of necrotizing myelopathy associated with leukemia reported in the English medical literature, and the first one demonstrating usefulness of magnetic resonance imaging in diagnosis of necrotizing myelopathy.

Intramedullary lipoma of the distal femur.

A rare case of intramedullary lipoma involving the distal femur is presented and discussed in relation to previously reported cases. The 26 previously reported extracranial cases of this bone lesion are briefly reviewed. Emphasis is placed upon establishing a definitive pathologic diagnosis by open biopsy when one is dealing with a large bony lesion that has indefinite radiologic features.

Postmortem demonstration of esophageal varices by a simple method.

The usual methods available to demonstrate esophageal varices in postmortem material have met with little success because of their unreliability, difficulty to execute, or cost. A simple, inexpensive method, which consists in separating the esophageal mucosa and submucosa from the muscularis and stretching the former over a suitable absorbent paper, is described. In a few minutes, as the adherent membrane dries, the submucosal vascular pattern gradually develops, and after overnight drying, even the smallest venules are clearly visible. The specimen can be stored dry, photographed, or made into a more permanent preparation in a few days. The esophageal mucosal vascular patterns in groups of patients who died with a variety of hepatic diseases and other potential causes of esophageal varices were studied and compared with controls. A consistent pattern of prominent venous trunks located towards the distal third of the esophagus was seen in most specimens from cirrhotic patients, predominantly in micronodular forms with severe lobular distortion. Other potential causes of esophageal varices (hepatic tumors, congestion, etc.) resulted in less predictable vascular patterns.