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Biomedical subjects

R Umeda

Publications and source records attributed to R Umeda.

85 records · Page 5Linked to original sources

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.

Adult↗

Malignant lymphoma of the parotid gland.

A case of malignant lymphoma of the parotid gland was described. A 15-year-old male developed a mass which was a firm and non-tender. The patient underwent a superficial parotidectomy with preservation of the facial nerve. The tumor was a grey, soft mass, 3 X 4 X 4 cm in size. On microscopic examination, the tumor was intraglandular lymph node with invasion of salivary gland tissue. The tumor cells were seen between acini and ducts. A diagnosis of lymphosarcoma, prolymphocytic, nodular type was made according to the WHO's classification system and the patient was refered for radiation therapy. Further investigations, including radio-isotope scanning of liver, spleen and bone and a biopsy of bone marrow revealed no sign of the disease. The patient was treated with 5380R of cobalt irradiation and in follow-up of a one year's duration there was no recurrence. Our case fulfilled the criteria which was represented by Hyman and Wolff and we reviewed the literature of this condition.

Adolescent↗

Antinuclear antibodies in the sera of patients with nasopharyngeal carcinoma.

We studied the production of heterophile antinuclear antibodies (ANAs) in the sera of 50 patients, 20 with nasopharyngeal carcinoma (NPC) and 30 with other head and neck cancers (laryngeal cancer and maxillary cancer), before and after radiation therapy. A higher incidence of ANAs was found in the sera of patients with NPC and ANA production in these patients was higher after radiation therapy. We therefore performed in vitro experiments to explore the mechanisms of ANA production in the serum of postirradiated NPC patients. X-ray-irradiated NPC-derived cells (NPC-KT) produced a large amount of Epstein-Barr virus (NPC EBV) compared with non-irradiated NPC-KT cells. Nasopharyngeal carcinoma EBV-infected lymphocytes produced high levels of ANAs. These data suggest that lymphocytes infected by EBV from NPC cells may produce ANAs in the sera of NPC patients.

Antibodies, Antinuclear↗

Epstein-Barr virus activation of human epithelial-nasopharyngeal carcinoma hybrid cells.

The authors used indirect immunofluorescence and electron microscopic techniques to study the effects of 5-iododeoxyuridine (IUDR) and the tumor promotor 12-O-tetradecanoylphorbol-13-acetate (TPA) on the epithelial hybrid cell line (NPC-KT) derived from nasopharyngeal carcinoma. The hybrid cells contained Epstein-Barr virus (EBV)-induced early antigens at a very low level but not Epstein-Barr viral capsid antigens in spontaneous production; the hybrid cells responded significantly to both IUDR and TPA induction. The chemicals induced both early antigens and viral capsid antigens in the NPC-KT cells. Moreover, the virus particles were detected in the altered NPC-KT cells by IUDR treatment. The data suggest that the EBV-induced agents activate the EBV productive cycle in a proportion of nasopharyngeal carcinoma cells.

Antigens, Viral, Tumor↗

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.

Antigens↗