Ryozo Umeda

Establishment of Epstein-Barr virus (EBV)-associated nuclear antigen (EBNA)-positive nasopharyngeal carcinoma hybrid cell line (NPC-KT)

SummaryPrimary nasopharyngeal carcinoma (NPC) cells were fused to hypoxanthine-guanine phosphoribosyltransferase (HGPRT)-defective cells derived from adenoid tissues using Sendai virus. Some of the fused cells developed into epithelial-like hybrid cells in a selective HAT medium. The hybrid cells (NPC-KT) were Epstein-Barr virus (EBV)-associated nuclear antigen (EBNA)-positive cells. There have been no reports on the establishment of EBNA-positive epithelial cell lines derived from NPC. Thus, the epithelial-like hybrid cells might serve as an in vitro model for studying the biologic activity of NPC-associated EBV.

Significance of Intravenous Olfaction Test Using Thiamine Propyldisulfide (Alinamin) in Olfactometry

The significance of intravenous olfaction test in olfactometry was studied by injection of thiamine propyldisulfide (Alinamin) intravenously. An original solution of Alinamin is a thiol-type derivative of vitamin B1, and releases a mercaptan smell (garlic smell) in expired air when it arrives at the olfactory epithelium via the nasopharynx. In the intravenous olfaction test (Alinamin test), the latent time which is a period between the initiation of injection and recognition of garlic smell, and duration time which is a period between the recognition and disappearance of smell are measured. Our results indicated that latent time is influenced by olfactory acuity and duration time depends on olfactory adaptation phenomenon. Central olfactory disorders were highly suspected in hyposmia patients with duration time of less than 15 sec, and nonresponders in Alinamin test always showed poor prognosis in the recovery of olfactory acuity. It was considered that the Alinamin test is useful not only for estimating the degree of olfactory disorders, but also for differential diagnosis of impaired lesions and olfactory prognosis.

Hamartoma of the tongue

Hamartomas of the tongue are rare. A case of a 6-year-old girl with hamartoma at the base of the tongue is reported. The diagnosis was confirmed by a histopathologic examination of the mass after removal in a wedge fashion by the CO2 laser under general anesthesia. The literature is reviewed and discussed.

Differences in the ability of cells to fuse are mediated by strains of epstein-barr virus

Epstein‐Barr virus (EBV) preparations from both NPC‐KT cells (NPC‐EBV) and P3HR‐1 cells (HR‐l‐EBV) can induce cell fusion between EBV receptor (EBVR)‐positive Raji cells and EBVR‐negative cells, but other strains of EBV cannot induce cell fusion. The effect of these two EBV isolates on ability of cells to fuse has been studied to determine if there are differences in the biological properties of the different EBV isolates, particularly the isolates obtained from nasopharyngeal carcinoma such as NPC‐EBV. The frequency of cell fusion between NPC‐EBV‐superinfected Raji cells and EBVR‐negative epithelial cells (Ad‐AH) was increased more than 30‐fold in the presence of medium containing 1% dimethylsulfoxide (DMSO). However, the frequency of cell fusion between HR‐1‐EBV‐superin‐fected Raji cells and Ad‐AH cells was unaffected under the same conditions. The data show that differences in the ability of cells to fuse ore induced by variants of EBV in response to DMSO. These differences may be important in elucidating the different biological properties of EBV isolates and might have implications for the pathophysiology of EBV‐associated illness.

Epstein-Barr Virus Nuclear Antigen-Positive Nasopharyngeal Hybrid Cells

An epithelial-like hybrid cell line was established by cell fusion of 8-azahypoxanthine-resistant epithelial cells (Ad-AH) with lymphoblastoid cells (A2L), derived from the human nasopharynx. The nasopharyngeal hybrid cells, designated as A2L/AH, were Epstein-Barr virus (EBV)-associated nuclear antigen (EBNA)-positive by the anticomplement immunofluorescence method. Furthermore, the treatment of the hybrid cells with 5-Iodo-2′-deoxyuridine (IUDR) induced early antigen (EA) and viral capsid antigens (VCA), while the treatment of nonproducer lymphoblastoid cells, A2L, induced EA but not VCA. The appearance of IUDR-induced VCA in the hybrid cells suggests that some factor produced by the Ad-AH cells might neutralize a repressed state of VCA and thus activate these antigens with the treatment of IUDR. These established nasopharyngeal hybrid cells might be useful for studies of in vitro nasopharyngeal carcinoma (NPC) since no EBV-carrying NPC cell lines have been established.

Electro-Olfactogram (EOG) in Olfactometry

The electro-olfactogram (EOG) is a potential originated in olfactory epithelium evoked by odorous stimulation, which has been demonstrated and termed by Ottoson (1959). In order to ascertain the clinical application of EOG, we attempted to record similar potentials in human subjects. In some preliminary experiments using rabbits, it was quite easy to produce Ottosons findings. In human subjects, however, there were sometimes great technical difficulties owing to the hidden anatomical position of the olfactory epithelium. Then we utilized Olympus selfoscope endoscopy for placing and retaining the electrode to the olfactory portion precisely and safely, with a tube for sending airborne odor. As results, we succeeded in recording negative spike discharge similar to Ottosons findings. We examined a total of 27 nasal cavities in 22 patients with peripheral olfactory disorders and 11 nasal cavities in 12 patients with central olfactory disorders. The positive EOG rate in patients with peripheral or central olfactory disorders was 28 and 69%, respectively. Moreover, the positive rate was decreased in proportion to the degree of olfactory disorders in chronic rhinosinusitis. No positive EOG was observed in anosmic nasal cavities, while it was 68% in normal persons and resulted in an equal value to anosmia group caused by the damage of central olfactory pathway. From these results, it is considered that the positive EOG study is the only method which provides objective finding for the differential diagnosis of anosmia caused by disorders of olfactory epithelium or disorders of central olfactory tract.

Importance of Unilateral Examination in Olfactometry

Hyposmia, the decreased sense of smell, and anosmia, the loss of sense of smell, may be unilateral or bilateral. If the olfactory acuity examined by means of bilateral test is normal, olfactory disorders are not found; unilateral examination is therefore necessary for definite evaluation of olfactory acuity. As evidence, 7 cases out of 94 patients with chronic rhinosinusitis and 6 cases out of 12 patients who received the surgery of anterior cranial fossa showed definite different olfactory threshold between nasal cavities, and there were no patients who recognized the diminished sense of smell in spite of unilateral high olfactory threshold. Additionally, we have experienced that a patient with brain tumor was diagnosed by the help of unilateral olfactory test. We thus strongly recommend the unilateral olfactometry as a method for simple and reliable test in clinical measurement of the sense of smell.

Intravagal parathyroid adenoma

An extremely rare case of intravagal parathyroid adenoma is presented. The tumour caused fusiform swelling of the left vagus nerve was shelled out. Post-operatively the left recurrent nerve palsy was recovered in the two months. Serum calcium level returned to normal on the tenth day after the surgical operation without symptoms of hypocalcaemia.

Nasopharyngeal Carcinoma in Japan —Clinical Evaluation of EBV Serology and EBV-Associated Nuclear Antigens Test—

This study was aimed at the possible clinical application of two Epstein-Barr virus (EBV) immunological tests to Japanese nasopharyngeal carcinoma (NPC). One of them was serological test to measure antibody titers to EBV-associated antigens (viral capsid antigens (VCA) and virus-induced early antigens (EA)) of 42 NPC sera. The other was for the detection of EBV-associated nuclear antigens (EBNA) in 22 tumour cells of NPC. The results showed that significant elevation of antibody titers to VCA and EA which resided particularly in IgA class as well as a high incidence in the presence of EBNA were found in undifferentiated NPC. Apart from its importance in etiology, EBV serology and the EBNA test may help clinicians to establish a diagnosis of undifferentiated NPC in Japan and there is little doubt that these tests should eventually become a routine biologic test in ENT practice.

Parapharyngeal schwannoma of the cervical sympathetic chain in a child

Parapharyngeal schwannomas of the cervical sympathetic chain are benign tumors that have not been reported in children, compared to parapharyngeal neuroblastomas. We present, to our knowledge, the youngest reported case of parapharyngeal schwannoma of the cervical sympathetic chain. The nerve of origin could be clearly ascertained when excision was made through a cervical approach.