Biomedical subjects

D C Naylor

Publications and source records attributed to D C Naylor.

11 recordsLinked to original sources

PubMed1988

Primary tumours of the thymus in the rat.

The features of 192 primary thymic tumours occurring in the rat are described. Of these neoplasms, 170 were classified as benign thymomas, one as a benign fibrous histiocytoma, 20 as various types of malignant thymoma, 3 lympho-epithelioma-like carcinomas, one mixed small cell undifferentiated-squamous cell carcinoma, one sarcoma-like carcinoma, 4 undifferentiated carcinomas, 11 squamous cell carcinomas and the one remaining tumour as a carcinoid. A mouse, anti-epithelial, monoclonal antibody, lu-5, was used to confirm the epithelial nature of the malignant thymomas, and neuron-specific enolase to confirm the diagnosis of carcinoid. The tumours showed many features in common with those reported in man.

Animals↗

PubMed1988

Rat endomyocardial disease: a neural origin?

Of 58 cardiac lesions in rats from a Sprague-Dawley-derived strain, representing different stages of endomyocardial disease including 10 cases progressing to tumors, most stained positively for S-100 protein, while duplicate sections of selected cases also reacted positively for neuron-specific enolase. The results demonstrate the probable neural origin of these lesions.

Age Factors↗

PubMed1986

A comparison of endomyocardial disease in the rat with endomyocardial fibrosis in man.

The features of 39 cases of spontaneous endomyocardial disease occurring in the rat heart are discussed and the condition is compared with endomyocardial fibrosis occurring in man. Rat endomyocardial disease is an age-related change characterized by subendocardial proliferation of spindle cells that may progress to a lesion histologically similar to fibrosarcoma. Human endomyocardial fibrosis, on the other hand, is not age-related and shows essentially fibrohyaline changes of low cellularity preceded by the occurrence of acid mucopolysaccharides in the subendocardial region; no evidence of malignant change has ever been reported.

Animals↗

PubMed1985

The incidence of naturally-occurring primary brain tumours in the laboratory rat.

Histological analysis of 90 spontaneous primary tumours of the brain observed among 8960 ageing rats (Sprague-Dawley-derived) revealed 55 granular-cell meningiomas, 19 neoplastic reticuloses, 11 neuroglial tumours, 4 pineal tumours, and one pleomorphic, meningeal sarcoma. Although all these tumour types can occur in man and other animal species, the high incidence of granular-cell tumours, and the low degree of differentiation of some neuroglial and pineal tumours, appear to be characteristic attributes of the rat.

Animals↗

PubMed1985

Pyridoxine megavitaminosis: an analysis of the early changes induced with massive doses of vitamin B6 in rat primary sensory neurons.

The early effects of high toxic doses of vitamin B6 (pyridoxine) on the peripheral sensory neurons were studied in laboratory rats. The animals were treated with 600 mg/kg of pyridoxine hydrochloride by intraperitoneal injection twice daily. Thereafter they were killed by perfusion-fixation at periods ranging from one to 14 days and the tissues were examined by light and electron microscopy. The primary change consisted of the formation of swollen membranous profiles in both the axon hillock and the initial axonal segment of the large dorsal root cytons. This change occurred within 24 hours of exposure, and was followed by an axonal reaction of the nerve cell bodies and by secondary degeneration of their processes. These findings identify the probable target site for pyridoxine toxicity, and establish a simple animal model for studying not only sensory denervation, but also the axonal reaction and secondary degeneration.

Animals↗

PubMed1981