Interleukin 1, an immune response-generated cytokine that stimulates astrocyte proliferation and reactivity (astrogliosis), was present in up to 30 times as many glial cells in tissue sections of brain from patients with Down syndrome and Alzheimer disease compared with age-matched control subjects. Most interleukin 1-immunoreactive glia in Down syndrome and Alzheimer disease were classified as microglia. The number of interleukin 1 immunoreactive neurons did not appear to differ in Down syndrome and Alzheimer disease compared with control brain. Numerous temporal lobe astrocytes in Alzheimer disease and postnatal Down syndrome were intensely interleukin 1-, S-100-, and glial fibrillary acidic protein-immunoreactive and had reactive structure. Interleukin 1 levels in Alzheimer disease temporal lobe homogenates were elevated, as were the levels of S-100 and glial fibrillary acidic protein, two proteins reportedly elevated in reactive astrocytes. These data suggest that increased expression of S-100 in Down syndrome, resulting from duplication of the gene on chromosome 21 that encodes the I6 subunit of S-100, may be augmented by elevation of interleukin 1. As a corollary, the astrogliosis in Alzheimer disease may be promoted by elevation of interleukin 1.

No abstract

The clinical and radiographic presentations of 3 patients with intraventricular cavernous hemangioma are described. The accumulated total of 19 cases from the literature are compared to determine whether there is a common clinical and radiographic presentation for this benign intraventricular lesion. The differential diagnosis of intraventricular cavernous hemangioma includes intraventricular meningioma, choroid plexus papilloma, arteriovenous malformation, low grade astrocytoma, and ependymoma.

Analysis of myelin from a leukodystrophic brain was performed (Pelizaeus-Merzbacher disease, classical type). Myelin recovery was 7% of normal, when isolated by ultracentrifugation. Electron microscopy showed a great amount of loose lamellae, with less thick sheaths and periodicity close to normal. This myelin contains fewer lipids than normal, sphingolipids and plasmalogens being reduced. Fatty acids from phospholipids are essentially normal, however enols from plasmalogens are largely reduced. Purified sphingolipids (cerebrosides, sulfatides and sphingomyelin) present a considerable diminution in very long chain fatty acids; the ratio of very long chain fatty acids (over C I8) on shorter chains is 1% of the normal value for saturated fatty acids and 2% for the monounsaturated homologues. Protein analysis showed that basic protein and proteolipids were reduced, Wolfgram proteins being relatively increased.

No abstract

Biochemical analysis of the leukodystrophic brain from a case of Pelizaeus-Merzbachcr disease, classical type. was performed. A decrease in the amount of solid material present was found. The lyophilized brain weight was reduced to 76% of normal with a slightly greater decrease in the amount of extractable lipid. Total myelin was diminished to 7% of normal. Among specific lipids plasmalogens were present in slightly lowered amounts. Cerebrosides and sulphatides were drastically reduced to 8% of normal. whereas sphingomyelin was less severely affected. Fatty acids from phospholipids were close to normal. only enols being slightly diminished. Analysis of pure cerebrosides and sulphatides revealed that the a-hydroxylated compounds as well as very long chain fatty acids (over CI8. especially C,, to CZ6) were greatly reduced. For chain lengths over C,,,, the ratio of leukodystrophic fatty acid to normal fatty acid was close to 10%. The defect in very long chain fatty acids is estimated at 99.204 in total brain. Thus, we have found a marked decrease in the amount of very long chain fatty acids and a less marked decrease in sphingolipids. The reduced amount of these acids appears to be partially oflsct by an increase in the amount of medium-chain fatty acids in sphingolipids. We conclude that one aspect of Pclizaeus-Mcrzbacher disease may be a defect in the synthesis of myelin very long chain fatty acids (as these acids are far much reduced than any other myelin molecule).

No abstract

A neonate with a cerebral gliosarcoma was found to have chromosome abnormalities in tissue culture of the tumor, but normal karyotyping of peripheral blood. Similarities to and differences from chromosome abnormalities found in other human gliomas are noted. Unusual exposure of the child to heptachlor during prenatal development and the neonatal period suggests the need for further studies on the role of toxins in oncogenesis.