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Biomedical subjects

C Nagata

Publications and source records attributed to C Nagata.

At least 163 records · Page 9Linked to original sources

Unapproved use of high-dose combined pills in Japan: a community study on prevalence and health characteristics of the users.

BACKGROUND: Because of the ban on oral contraceptive use in Japan, only high-dose combined pills (HDCP), permitted as treatment for menstrual disorders, can be used as a contraceptive. We determined the prevalence of the use of such preparations in a community in Japan and assessed the health characteristics of the users. METHODS: A total of 18,435 female residents age 35 years and over in a city of Gifu Prefecture, Japan, responded in 1992 to a health questionnaire that included questions on the use of HDCP, lifestyle, and dietary habits. The response rate was 92%. RESULTS: The rates of current and past HDCP use were 1.3 and 7.1%, respectively, among women ages 35-49 years, and 2.2% of the women had used HDCP for longer than any other method of contraception. Current HDCP users were more likely to be smokers. They had lower intakes of carotene, fiber, and vitamins C and E and a lower polyunsaturated/saturated fat ratio than never-users. CONCLUSIONS: The prevalence of HDCP use was 1.3% among Japanese women ages 35-49 years. Potential risk factors for cardiovascular diseases, such as smoking and a diet with lower intakes of antioxidants, were prevalent among current HDCP users.

Adult↗

Cigarette smoke induces DNA single-strand breaks in human cells.

Epidemiological evidence suggests that smoking is a major cause of human lung cancer. However, the mechanism by which cigarette smoke induces the cancer remains obscure, although in tobacco carcinogenesis, promotion and/or co-carcinogenesis may have crucial roles. The epidemiological data show that if an individual stops smoking, the risk of his contracting lung cancer increases no further. Moreover, laboratory experiments show that cigarette smoke condensate (CSC) exhibits co-carcinogenic and promoting activities in tumour production and malignant transformation. Clastogenic action is thought to be intimately involved in tumour promotion, and it is therefore interesting that visible chromosome changes such as chromosome aberrations and sister chromatid exchanges are known to be caused by cigarette smoke. However, there has been no previous direct demonstration that cigarette smoke can cause single-strand breaks (SSB) in DNA. Here we report that cigarette smoke induces considerable numbers of DNA SSB in cultured human cells, and that such strand breaks may be ascribed to active oxygen generated from cigarette smoke.

Cells, Cultured↗