• Biomolecules & Therapeutics
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• v.25 no.5
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• pp.545-552
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• 2017

Increasing concern is being given to the association between risk of cancer and exposure to low-dose bisphenol A (BPA), especially in young-aged population. In this study, we investigated the effects of repeated oral treatment of low to high dose BPA in juvenile Sprague-Dawley rats. Exposing juvenile rats to BPA (0, 0.5, 5, 50, and 250 mg/kg oral gavage) from post-natal day 9 for 90 days resulted in higher food intakes and increased body weights in biphasic dose-effect relationship. Male mammary glands were atrophied at high dose, which coincided with sexual pre-maturation of females. Notably, proliferative changes with altered cell foci and focal inflammation were observed around bile ducts in the liver of all BPA-dosed groups in males, which achieved statistical significance from 0.5 mg/kg (ANOVA, Dunnett's test, p<0.05). Toxicokinetic analysis revealed that systemic exposure to BPA was greater at early age (e.g., 210-fold in $C_{max}$, and 26-fold in AUC at 50 mg/kg in male on day 1 over day 90) and in females (e.g., 4-fold in $C_{max}$ and 1.6-fold in AUC at 50 mg/kg vs. male on day 1), which might have stemmed from either age- or gender-dependent differences in metabolic capacity. These results may serve as evidence for the association between risk of cancer and exposure to low-dose BPA, especially in young children, as well as for varying toxicity of xenobiotics in different age and gender groups.

• Journal of Families and Better Life
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• v.30 no.2
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• pp.137-152
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• 2012

The graying of populations is emerging as an international issue around the world, and this is a problem that is rapidly advancing in Korea as well, signaling the need for financial preparations for the aged. For this purpose, various retirement pension systems are being employed as preparatory measures for the nation's elderly. Using data from 1474 people in the 2007 panel study of National Security for the Retired, the present work attempts to look at satisfaction rates with regard to public pension receipts for the national pension and special occupational pensions according to general characteristics and factors related to the preparation for an aging society. Satisfaction with retirement pension receipts according to the type of pension was high for special occupation retirement pensions, individual retirement pensions and the national retirement pension, in that order. Looking at satisfaction rates based on the general characteristics of pension recipients, the study revealed that for the national pension, satisfaction was highest for groups with above-average physical and psychological health, groups who think appropriate living expenses for the elderly are lower, groups in which a partner also earns income, and groups who had amply prepared for their expected living expenses in later life. Regarding special occupation retirement pensions, satisfaction was high for groups over the age of 70, groups with good psychological health, and groups sufficiently prepared for their living expenses in later expenses, compared to groups for which these factors did not apply. In terms of the relative influences impacting retirement pension recipient satisfaction, satisfaction with the national pension was highest when the primary source to cover elderly living expenses was a resource other than income earned by the recipient and their partner and/or income received from children. Concerning special occupation retirement pensions, satisfaction was highest among those whose education terminated before middle school, and for those in good physical health. Based on the above results, it is vital that plans exist for preparing sufficiently for the living expenses of the elderly and for facilitating the physical and psychological health of pension recipients. Plans are also necessary to, ensure that citizens are provided with easily accessible educational programs and activities regarding general installment savings and deposits, stocks and bonds, real estate investments, individual retirement pensions, private insurance, severance pay pensions, and public pensions.