Biomedical subjects

T Donjyo

Publications and source records attributed to T Donjyo.

3 recordsLinked to original sources

PubMed1998

[Study of the function of nerve growth factor in the olfactory tract of the mouse].

The aim of this study was to examine the function of nerve growth factor (BGF) in the olfactory tract of mice. Using the mice which had received unilateral olfactory bulbectomy and in which antibodies to NGF had been continuously infused with into the contralateral olfactory blub, three kinds of analysis were performed: histological analysis of the olfactory epithelium by HE staining, immunohistochemical analysis of the olfactory epithelium using polyclonal antibodies to trk which forms the NGF receptor, and olfactory-mediated behavioral analysis with cycloheximide. These animals had been sacrificed at day 1, 3, 7, 14, 21 or 28. Several findings were obtained as a result of the above analysis. Degeneration of the olfactory epithelium and trk expression by the olfactory cells were observed on day 7, and the olfactory epithelium was incompletely regenerated on day 28. However, trk expression by the olfactory cell was still recognized and the olfactory function was not restored by day 28. These examinations suggest that NGF produced in the olfactory bulb was transported retrogradely to olfactory cells through the olfactory nerves, and was associated with sustaining the existence of those cells and with regenerating the olfactory tract after injury.

Animals↗

PubMed1992

[Clinical observations on parosmia].

We reviewed the clinical records of 15 patients with parosmia examined in our department from April 1987 to September 1990. Seven (29.2%) of 24 patients with olfactory disturbance caused by traumatic injury complained of parosmia. Eight (23.2%) of 34 patients with olfactory disturbance caused by influenza also showed parosmia. The incidence of parosmia between two groups was not statistically significant (p greater than 0.05). Parosmia was observed in none of 42 patients with olfactory disturbance caused by nasal-paranasal diseases. All patients (n:15) always perceived odors as unpleasent. Twelve of them had spontaneous parosmia, and three patients recognized the unpleasant smell when an odor came. In comparison with the auditory system, we speculated that spontaneous parosmia resembles tinnitus. The cause of tinnitus is recognized as a disturbance of the auditory nerve (the first order neuron). Tinnitus is rare in patients with conductive hearing loss, and cases of olfactory disturbance of the "respiratory dysosmia" did not complain of parosmia. Post-traumatic olfactory disturbance is caused by transection of the fila olfactoria, which is part of an olfactory neuron, while post-inflammatory olfactory disturbance is caused by damage to olfactory receptor cells. Furthermore, the fact that the incidence of parosmia between the two groups was not statistically significant suggests the same etiological mechanism in receptor cells. We consider that parosmia is caused by damage to olfactory sensory neurons.

Adolescent↗

PubMed1989

Ranula and sarcoid granuloma of a sublingual gland.

A case is reported in which the treatment of the ranula consisted of dissection of the cystic wall along with excision of the sublingual gland of origin. The histological picture of the gland was consistent with sarcoidosis. Thereafter, all other examinations were negative for sarcoidosis. However, there remains the possibility that the lesion may be the precursor of widespread sarcoidosis which might occur in the future.

Adult↗