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Biomedical subjects

N B Rewcastle

Publications and source records attributed to N B Rewcastle.

At least 37 records · Page 2Linked to original sources

Methanol optic neuropathy: a histopathological study.

The histopathologic effects of methanol on the optic nerve were studied in four patients. Circumscribed myelin damage occurred behind the lamina cribrosa in each nerve. Axons were preserved. Demyelination also occurred in cerebral hemispheric white matter in one patient. This selective myelinoclastic effect of methanol metabolism is probably caused by histotoxic anoxia in watershed areas of the cerebral and distal optic nerve circulations. Juxtabulbar demyelination may cause optic disk edema in methanol poisoning by compressive obstruction of orthograde axoplasmic flow. Visual loss may be due to disruption of saltatory conduction. Retrolaminar demyelinating optic neuropathy is an early morphologic correlate of visual loss in methanol intoxication.

Brain Diseases↗

Gonadotroph cell adenoma of the pituitary in a women with long-standing hypogonadism.

A 57-year-old woman, with long-standing hypogonadism secondary to irradiation of the ovaries, was found to have a pituitary tumor which was removed and investigated by histology, immunocytology and electron microscopy. Histologically, the tumor corresponded to a chromophobe, slightly PAS positive adenoma and the immunoperoxidase stain revealed the presence of both FSH and LH in the cytoplasm of the adenoma cells. The structural features of the adenoma cells resembled those of FSH cells in the nontumorous adenohypophysis. We thus believe that pituitary adenomas consisting of gonadotrophin-producing cells occur and that these may produce both FSH and LH. The relation between the gonadotrophin-producing adenoma and the preceding hypogonadism is uncertain.

Adenoma↗

Pituitary adenomas associated with elevated blood follicle-stimulating hormone levels: a histologic, immunocytologic, and electron microscopic study of two cases.

The histologic, immunocytologic, and electron microscopic features of pituitary adenomas surgically removed from two men with elevated levels of blood follicle-stimulating hormone (FSH) are described. In both cases, the high blood FSH levels were reduced after surgery. By light microscopy, the tumors corresponded to chromophobic adenomas, and the immunoperoxidase technique revealed the presence of immunoreactive FSH (beta-subunit) in the cytoplasm of the adenoma cells. By electron microscopy, the adenoma cells differed considerably from nontumorous FSH cells. They were smaller and angular and contained numerous microtubules as well as spherical secretory granules measuring 100 to 250 nm in diameter and often lining up along the cell membranes. The present findings are consistent with the view that FSH-producing adenomas may originate in the human pituitary.

Adenoma↗

Bilateral dissecting aneurysms of the intracranial internal carotid arteries in an 8-year-old boy.

Nontraumatic intracranial dissecting aneurysms have rarely been reported as the cause of acute infantile and childhood hemiplegia. The present case is unique because dissecting aneurysms occurred bilaterally in two clinically distinct episodes. A recent dissecting aneurysm of the right intracranial internal carotid artery was present with a healed dissecting aneurysm of left internal carotid artery in an 8-year-old boy.

Aneurysm↗