• Journal of Preventive Medicine and Public Health
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• v.43 no.2
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• pp.131-137
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• 2010

Objectives: Bisphenol A diglycidyl ether (BADGE) is a liquid compound obtained by condensation of two molecules of epichlorohydrin with one molecule of bisphenol A. General and reproductive toxicity with BADGE has been reported higher than 1000 mg/kg/day. This study was performed to show the effects of acute exposure to BADGE below 1000 mg/kg/day on the testis in adult male rats. Methods: BADGE was administered by gastric lavage in a single dose of 500, 750, 1000, and 2000 mg/kg/day in 8-week old male SPF Sprague-Dawley rats. The right testis was processed for light microscopic analysis. The left testis was homogenized and spermatids were counted to determine the daily sperm production and daily abnormal sperm production. The sperm count, sperm motility, and incidence of abnormal sperm were estimated in the epididymis. In testicular sections, the seminiferous tubules were observed for qualitative changes. The progression of spermatogenesis was arbitrarily classified as full-matured, maturing, and immature. The specimen slide was observed at 3 points and 10 seminiferous tubules were evaluated at each point. Results: The male rats exposed to single oral dose of BADGE at 750, 1000, and 2000 mg/kg/day were significantly increased the number of immature and maturing sperm on the testis. There were no significant differences with respect to sperm head count, sperm motility, and sperm abnormality in the BADGE treatment groups. Conclusions: These results suggest that single oral exposure of BADGE 750 mg/kg/day can affect adult male testis development.

• Toxicological Research
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• v.20 no.3
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• pp.241-250
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• 2004

We previously found that bisphenol A (BPA) caused neurotoxic behavioral alteration. Since disturbance of calcium homeostasis is an implicated contributor in the neurotoxic mechanism of environmental toxicants, we investigated whether BPA alters calcium homeostasis. Unlike other neurotoxic agents which cause increase of intracellular calcium level, BPA decreased $[Ca^{2+}]_i$ dose-dependently in PC12 cells and cortical neuronal cells regardless of the calcium existence in buffer. BPA at greater concentrations than 100 $\mu\textrm{M}$ reduced cell viability significantly in both types of cells. BPA also suppressed L-glutamate (L-type channel activator, 30 mM) and trifluoperazine (calmodulin antagonist, 30 $\mu\textrm{M}$)-induced increase of $[Ca^{2+}]_i$. BPA further lowered caffeine (RYR activator, 100 $\mu\textrm{M}$)-decreased $[Ca^{2+}]_i$, but did not alter dantrolene (RYR inhibitor, 100 $\mu\textrm{M}$), heparin (IP3 inhibitor, 200 units/ml) and xestospongin C (IP3 inhibitor, 5 $\mu\textrm{M}$)-decreased $[Ca^{2+}]_i$. Cell viability was not directly related to intracellular calcium change by bisphenol A that alternation of intracellular calcium may not be a direct causal factor of BPA-induced neuronal cell death.

• Environmental Analysis Health and Toxicology
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• v.20 no.1
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• pp.13-21
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• 2005

The purpose of this study was to determine the effects of bisphenol A (BPA), which is known to have estrogenic activity, on the early development of medaka fish (Oryzias latipes). The fertilized eggs of medaka were treated with BPA at different concentrations for 3 weeks. Embryonic growth, deformation, hatching success, and gonadal differentiation were determined to observe the effects of this chemical. Also we tried to measure the estrogenic activity of bisphenol A using ELISA and RT-PCR methods. By using this techniques, we evaluated the induction of vitellogenin, an estrogen-regulated gene from the whole body-homogenates of larvae. At results, a reduced blood circulation was seen in embryos and peritoneal edema and hindrance of yolk-sac absorption were observed in larvae of treated group. However, BPA at the concentrations tested (2～200 ㎍/L) did not have severe adverse effects on the early life-stages. According to the observation of gonadal histology, inter-sex or sex -reversal was not found in all test fish. After the exposure was ended, vitellogenin mRNA and protein levels were measured in larvae and then their levels were found to be increased in treated group with 200㎍/L. These results indicate that BPA can induce the expression of vitellogenin in early life-stages as well as in adult male fish.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2711-2715
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• 2012

Background: Bisphenol A (BPA), an endocrine disrupting chemical, has been suspected to pose carcinogenic risks. However, likely mechanisms are obscure and there are difficulties to estimating its real significance for cancer development. Methods: We therefore studied BPA-induced proteomic alterations in immune organs of ICR mice offspring that were prenatally exposed to BPA (15 and 300 mg/L of drinking water). We performed 2D-gel analyses of samples, considering differences in spleen, exposure levels, sex, and ages. Results: From proteomic analyses, we found various proteins were up- or down-regulated by BPA. Among them, SET, a putative oncogene and inhibitor of phosphatase 2A, was significantly down-regulated in a BPA dose-dependent manner. We also confirmed down-regulation of SET in western blot and real time PCR analyses. From gene network analysis, SET is predicted to communicate with other genes including CYP17, which is involved in biosynthesis and metabolism of sex-hormones. Conclusions: This study provided evidence that SET can be applied as a new biomarker for prenatal BPA exposure and suggests a potential new mechanism of action in that BPA may disrupt CYP17 via SET.

• Journal of Environmental Science International
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• v.30 no.12
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• pp.1005-1014
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• 2021

Organic contaminants can be released into water environments due to chemical accidents and exist as dissolved and non-aqueous phase liquids (NAPL). Fenton oxidation was tested for bisphenol A and nitrobenzene as model organic contaminants in dissolved and NAPL states. Fenton oxidation was successfully applied for both of the dissolved and NAPL states of the two pollutants and the results indicated that a quick treatment was needed to reduce the risk from a chemical accidents instead of carrying out oxidation after the contaminants dissolve in water. A set of Fenton reactions were tested under seawater conditions because chemical accidents often occurs in the ocean. Chloride ions act as radical scavengers and inhibit Fenton oxidation. The reaction rate is inversely proportional to salt contents and the reduced reaction rate can be compensated by increasing the quantity of the oxidizing agents. The current study showes that Fenton oxidation could be applied as a quick treatments for organic contaminant in dissolved and NAPL state organic contaminants released as a result of leaks or chemical accidents.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.3
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• pp.192-196
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• 2004

The in vitro effect of bisphenol A (BPA) on ovarian steroidogenesis of the longchin goby (Chasmichthys dolichognathus) was investigated. Oocytes taken during the maturing phase (vitellogenic, fully vitellogenic or germinal vesicle breakdown stage) were incubated with BPA (100 ng/mL) in the presence of exogenous precursor $^{3}H-17\alpha\;hydroxyprogesterone\;(^{3}H-17\alphaOHP).$ Steroids were extracted from the media and the isolated oocytes, and the extracts were separated and identified by thin layer chromatography and gas chromatography-mass spectrometry. The identities of the major metabolites were progestogens $[17{\alpha}-hydroxy,20{\alpha}-dihydroprogesterone\;(17{\alpha}20{\alpha}OHP)\;and\;17{\alpha}-hydrxy,20{\beta}-dihydroprogesterone\;(17{\alpha}20{\beta}OHP),$ androgens [androstenedione (A4) and testosterone (T)] and estrogens [estrone $(E_1)\;and\;estradiol-17{\beta}(E_2)].$ BPA treatment inhibited production of estrogens in all the maturing phases and progestogens in the germinal vesicle migrating stage. Percentage yield of estrogens was decreased with increased yield of androgens. In conclusion, BPA had an inhibitory effect on the conversion of $^3H-17\alphaOHP$ to estrogens and progestogens. These results demonstrate that BPA can act either estrogenic or anti-estrogenic effects.

• Environmental Analysis Health and Toxicology
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• v.23 no.4
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• pp.291-299
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• 2008

Bisphenol A diglycidyl ether(BADGE)는 비스페놀 A와 에피클로로하이드린의 축합에 의해 만들어지는 물질로 상업용 액상 에폭시 수지의 주성분이다. 본 연구는 clusterin mRNA 발현이 BADGE의 노출된 생식기계 독성에 연관되어 있는지를 연구하기 위해 수행하였다. BADGE는 SPF Sprague-Dawley 임신 랏트에 임신 6일부터 수유기가지 하루에 한 번 0(대조군)과 375mg/kg/day를 경구 투여하였다. 수컷 새끼는 일반 사항과 몸무게, 일반 발달 지표(예, 항문과 생식기 사이의 거리, 이개개전, 절치붕출, 유두잔류, 안검개열, 고환하강, 포피박리 등)등을 관찰하였다. 대조군과 투여군에서 다섯 마리의 수컷 새끼는 출생 후 3, 6와 9주에 부검하여 부고환의 조직학적 변화 등을 관찰하였다. BADGE 375 mg/kg/day 투여군에서 항문과 생식기 사이의 거리는 대조군보다 길어지는 경향을 보였다. 출생 후 6주와 9주에서 부고환의 상대 무게는 대조군보다 약간 증가하였으나 조직학적인 변화는 관찰되지 않았다. BADGE 투여 군에서 clusterin mRNA 발현량은 대조군에 비해 3주에 56%, 6주에 57% 그리고 9주에 86% 감소하였다. 이런 결과는 랏트의 부고환에서 clusterin은 BADGE에 반응하는 유전자 중 하나일 수 있다는 가능성을 나타낸다.

• Journal of Korean Academy of Oral Health
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• v.41 no.4
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• pp.231-236
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• 2017

Objectives: The objectives of this study were to investigate the changes in bisphenol A (BPA) concentrations in urine from before to after sealant filling and the relationship between BPA and the number of teeth with sealed surfaces. Methods: Thirty-one children aged 6 and 7 years from three elementary schools in Daegu city who did not have any sealant and resin filling were selected as subjects. Urine samples were collected before and after sealant filling until 24 hours, with informed consent from their caregivers. The BPA concentration in all the collected urine samples was analyzed at Seegene Medical. Statistical analysis was performed using the Friedman test, Scheirer-Ray-Hope test, and the repeated-measures generalized linear mixed model of SPSS version 22.0. Results: The BPA concentrations increased from $3.49-{\mu}g/g$ creatinine before to $4.91-{\mu}g/g$ creatinine 2-3 hours later and to $4.15-{\mu}g/g$ creatinine after 24 hours. The more teeth with sealed surfaces, the higher the BPA concentration in children, but the difference was not statistically significant (P>0.05). Conclusions: The BPA concentrations were highest at 2-3 hours after sealant filling and decreased at 24 hours. Exposure to the sealant appears to have a meaningful correlation with the concentration of BPA in the urine of children.

• Conservation Science in Museum
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• v.26
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• pp.1-12
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• 2021

The bisphenol A epoxy resin currently used for the conservation of stone cultural heritage items is known to suffer from yellowing discoloration. In order to mitigate this yellowing and explore the availability of more diverse materials for the conservation of stone cultural heritage items, a hydrogenated Bisphenol A-based epoxy resin was prepared and compared with the epoxy resin currently used in the conservation treatment of stone cultural heritage items. The newly prepared epoxy resin showed improved physical properties relative to the existing materials, especially in terms of tensile strength, adhesion, and machinability, while the yellowing discoloration was reduced by a factor of roughly five to eight. The results suggest that epoxy resin could be used as a stable material for the conservation treatment of stone cultural heritage items, most of which are located outdoors.

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1065-1069
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• 2013

A highly sensitive electrochemical detection method for bisphenol A (BPA) has been developed by using multi-walled carbon nanotube (CNT)-doped titania-Nafion composite modified glassy carbon (GC) electrode. The CNT-titania-Nafion/GC electrode exhibited excellent electrocatalytic activity towards BPA. Therefore, the CNT-titania-Nafion/GC electrode showed improved voltammetric responses for BPA compared to that obtained with bare GC electrode. In addition, cetyltrimethylammonium bromide (CTAB), a cationic surfactant, was added into the BPA sample solution in order to accumulate BPA through hydrophobic interaction between CTAB and BPA. The CNT-titania-Nafion/GC electrode gave a linear response ($r^2$ = 0.999) for BPA from $1.0{\times}10^{-8}$ M to $5.0{\times}10^{-6}$ M with a detection limit of $9.0{\times}10^{-10}$ M (S/N = 3). The modified electrode showed good selectivity against interfering species and also exhibited good reproducibility. The present electrochemical sensor based on the CNT-titania-Nafion/GC electrode was applied to the determination of BPA in food package samples.