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Biomedical subjects

R O Barnard

Publications and source records attributed to R O Barnard.

At least 37 records · Page 2Linked to original sources
PubMed1985

Cerebral and retinal vascular changes in systemic lupus erythematosus.

A 16-year-old white boy with acute systemic lupus erythematosus (SLE) who presented with chorea and florid retinopathy died in renal failure three months after diagnosis. Pathological studies revealed two types of lesion in both the cerebral and ocular vessels. Some meningeal and choroidal vessels showed a typical vasculitis with fibrinoid necrosis, whereas other meningeal and retinal vessels were occluded by amorphous hyaline material in the absence of vasculitis.

Adolescent↗
PubMed1980

A note on the nature of eosinophilic granular bodies in astrocytic gliomas.

Eosinophilic granular bodies are a characteristic microscopical finding in certain gliomas of astrocytic type. The nature of these structures has been the subject of debate. The finding of a positive reaction for glial fibrillary acidic protein confirms the astrocytic nature of this material.

Astrocytes↗
PubMed1980

Polyneuritis cranialis as a presentation of malignant lymphoma.

Two cases of polyneuritis cranialis resulting from infiltration of nerve roots by malignant lymphoma are described, and 8 previously reported cases discussed. In these, cranial nerve involvement was the presenting feature of lymphoma, and lesions at other sites were inconspicuous until necropsy. In one patient infectious mononucleosis developed concurrently with the neurological deficit. The course of this condition is progressive and fatal.

Adult↗
PubMed1980

Astrocytic differentiation in medulloblastoma.

A case of cerebellar medulloblastoma with transitional features towards malignant fibrillary astrocytoma is described. In the cerebellum the tumour is characterised by extensive subpial infiltration with cells of undifferentiated type, and the astrocytic component could only be identified by a positive glial fibrillary acidic protein reaction. In the brainstem the character of the growth transforms to that of diffuse astrocytoma. This demonstrates the potential for differentiation existing in a "primitive" neuroepithelial neoplasm.

Astrocytes↗
PubMed1976

Myelin composition in acute and chronic multiple sclerosis in relation to cerebral lysosomal activity.

The neuropathology of 3 cases of acute multiple sclerosis was correlated with biochemical analyses. Astrocytosis was a characteristic feature of the diffuse demyelinating lesions in one case and lymphocytic cuffing characterized the well-defined plaques present in the white matter of the other two cases. No abnormalities were found in the protein or lipid composition of isolated myelin, despite a wide range of recovery. Nevertheless, the gel electrophoretic protein pattern of white matter adjacent to plaque areas showed selective loss of myelin basic protein. Lysosomal acid proteinase and beta-glucuronidase levels were very significantly increased in all white matter samples in which astrocytosis was a major neuropathological feature. Levels were less markedly raised in samples containing discrete active plaques. Enzyme changes were also found in the apparently normal white matter of 2 of the cases. Acid proteinase activity was in the normal range but the activities of beta-glucuronidase and acetylcholine esterase were elevated. The significance of these results in relation to glial cell activity in the early stages of demyelination is discussed.

Adolescent↗
PubMed1976

Perivascular lymphocytic cuffing in astrocytomas.

A series of cases of astrocytoma of differing cell composition and degree of malignancy was examined for the presence of reactive perivascular cuffing. Only surgical biopsy material was used. A correlation was made between perivascular lymphocyte cuffing and the presence of neoplastic astrocytes of the gemistocytic type.

Astrocytoma↗
PubMed1975

Patterns of proliferation in cerebral lymphoreticular tumours.

A study of eighteen cases of primary lymphoreticular tumours in the brain is described. In four of these there were extraneural lesions and in one macroglobulinaema. The use of whole brain sections embedded in celloidin, and of metallic impregnation methods, revealed certain constant patterns of proliferation. The tumours were diffuse and multicentric; the leptomeninges and perivascular spaces especially in the subependymal regions were frequently involved. Mature microglia were active both in infiltrated and in apparently tumour-free regions.

Adult↗
PubMed1974

Corpus callosum in multiple sclerosis.

A neuropathological study of 20 multiple sclerosis brains using celloidin-embedded slices was carried out to assess the extent of changes in the corpus callosum. Severe atrophy of the callosum was found in cases with marked hydrocephalus. Demyelination of the callosum varied in extent from slight involvement (with a few small plaques) to almost total myelin loss. A clinical history of mental deterioration was usual in the cases with severe callosal lesions, but no symptoms were recorded that indicated a specific disconnection syndrome. The ventricular enlargement noted in this series could not be explained either on the basis of obstruction to the flow of cerebrospinal fluid, or by the effects of shrinkage of the white matter.

Adult↗
PubMed1971

Pathological findings in a case of hypothyroidism with ataxia.

A case of hypothyroidism with ataxia is described. At necropsy there were degenerative changes in the cerebellum, particularly in the anterosuperior portion of the vermis, together with atrophy of ventral portion of the pons, transverse pontine fibres, and middle and superior peduncles. The relationship between ataxia and pathological findings in myxoedema is discussed.

Brain↗