• YAKHAK HOEJI
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• v.45 no.1
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• pp.55-63
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• 2001

In order to investigate the effects of bisphenol A (BPA) on immune system in mice we examined the various immunological parameters. After single oral administration of BPA to female ICR mice, the weights of bodies and lymphoid organs, splenic cellularity and hematological parameters were examined on day 2 and 7. Among them WBC and splenic cellularity were slightly decreased on day 2. To assess the effects of BPA on humoral immune responses, splenic IgM plaque forming cell (PFC) and serum IgM were assayed. When BPA was administered after immunization with SRBC, but not before immunization, IgM PFC against SRBC was significantly lowered in a dose dependent manner. Serum IgM level was also decreased on day 4 when high dose (2000 mg/kg) of BPA was administrated after injection of OVA-antigen. The indexes of splenocyte proliferation (SP) to concanavalin A (Con A) and bacterial lipopolysaccharide (LPS) were measured in vitro by MTT assay. At low concentration BPA slightly increased splenocyte proliferation but at higher concentration it showed significant inhibitory effects on cell proliferation. Mitogen-stimulated SP was also determined with spleen cells from BPA treated mice. Con A-induced SP was slightly decreased and LPS-induced SP was especially inhibited at 1000 mg/kg and 2000 mg/kg of BPA. These results indicate that BPA is able to acutly evoke humoral and cell mediated immune suppression in mice.

• Molecular & Cellular Toxicology
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• v.3 no.3
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• pp.185-189
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• 2007

Gene expression levels of choriogenin, vitellogenin and estrogen receptor were determined using Reverse transcription (RT)-PCR technique after exposure to estrogenic chemical bisphenol A in the Korean wild medaka (Oryzias sinensis). These genes have been known to be induced in male test fish when the fish are exposed to estrogenic chemicals. Therefore they can be suggested as a possible biomarker of endocrine disruption in fish, however, relatively little has been known about these genes expression by estrogenic chemicals in Korean wild fish. Mature male Oryzias sinensis were treated with bisphenol A at nominal concentrations of 0.02, 0.2 and 2 mg/L for 6 days and total RNA was extracted from the livers of treated fish for RT-PCR. When the five biomarker genes were amplified by RT-PCR in the same condition, mRNA induction level of each gene was elevated with different sensitivities. Conclusively, the results of this work indicated that measurement of vitellogenin and choriogenin using RT-PCR is effective as a simple tool for the screening of estrogenic chemicals and suggested that O. sinensis would be a suitable model fish for the environmental risk assessment of potential endocrine disruptors.

• Environmental Analysis Health and Toxicology
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• v.19 no.3
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• pp.271-278
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• 2004

Epoxy resins are mostly used as a molding material for drinking water tank. Bisphenol A is used at a constituent material for epoxy resins and is widely suspected to act as an endocrine disrupter. In this study, we investigated embryo hatching in zebrafish reared in water undergone leaching process of expoxy resin, and found a decreased survival rate. Bisphenol A eluted from epoxy resin in drinking water tank was completely degraded by TiO$_2$ photocatalysis. We detected 7.8 ng/ml of bisphenol A in epoxy resin tank, and observed that the concentration was undetectable after 48h photocatalysis over TiO$_2$. There was no toxicity in hatching rates in zebrafish and morphogenesis after photocatalysis. The effect of TiO$_2$ photocatalytic reactions on the catalase activities in the f]y stage of zebrafish was also examined. At 1 week post hatching, cataiase activities were higher both in the group of epoxy resin with 48 h TiO$_2$ photocatalysis and in the TiO$_2$ photocatalysis for 48 hours were higher than control group. However catalase activities of the treatment group of epoxy resin by TiO$_2$ photocatalysis for 48 hours were similar to control in 5 weeks post hatching fries. In conclusion, the toxicity of TiO$_2$ photocatalysis was not observed in this zebrafish.

• Journal of Marine Life Science
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• v.6 no.2
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• pp.73-79
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• 2021

Bisphenol A is a representative endocrine disruptor and continuously detected in aquatic environment due to wide use, resulting in adverse effects on growth, development, and reproduction in diverse organisms as well as human. Structural analogs have been developed to substitute BPA are also suspected to have endocrine disrupting effects. In the present study, the time-dependent expression patterns of ecdysteroid synthesis (nvd, cyp314a1), receptors (EcRA, EcRB, USP, ERR), and downstream signaling pathway - related genes (HR3, E75, Vtg, VtgR) were investigated using quantitative real time reverse transcription polymerase chain reaction (qRT-PCR) in the brackish water flea Diaphanosoma celebensis exposed to Bisphenol analogs (BPs; BPA, BPF, and BPS) for 6, 12, and 24 h. As results, the expression of nvd, cyp314a1, EcRs, USP, ERR and E75 mRNA was upregulated at 6 h exposure to BPF, which is earlier than BPA and BPS (12 h). On the other hand, HR3, E75 and VtgR mRNA levels were elevated at 6 h earlier at BPS and BPF than at BPA (12 h), but Vtg mRNA level was slightly changed within 24 h. These findings suggest that like BPA, BPF and BPS can also modulate the transcription of ecdysteroid pathway - related genes with different mechanisms, and have a potential as endocrine disruptors. This study will provide a better understanding the molecular mode of action of bisphenols on ecdysteroid pathway in the brackish water flea.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2005.10a
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• pp.46-46
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• 2005

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2005.10a
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• pp.46-46
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• 2005

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2001.11a
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• pp.80-80
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• 2001

• Korean Journal of Materials Research
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• v.4 no.8
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• pp.915-920
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• 1994

The thermal properties of Iliglycldyl ether of bisphenol A(DGEBA)-4, 4'-methylene dianiline (MDA)system with SN(Succinonitri1e) as a chain extender and HQ(Hydroquinone) as a reactive accelerator were investigated. Glass transition ternperature(Tg), heat deflection ternperature(HDT) and decomposition ternperature(Td) were measured with IiQ content in wh~ch SN : HQ content was fixed 4 : 1. Tg and HIIT were slightly decreased with increasing IIQ content. Td was stable at about $360^{\circ}C$ according to the changing HQ content and cure temperature.

• Korean Journal of Materials Research
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• v.4 no.7
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• pp.823-827
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• 1994

The mechanical properties of diglycidyl ether of bisphenol A(DGEBA)/4,4- methylene dianiline(MDA) system with the addition of malononitrile(MN) and hydroquinone(HQ) were investigated. The specimens which were prepared by curing at $150^{\circ}C$ for lhr after curing at $80^{\circ}C$ for 1.5hr were tested. The effects of MN as a chain extender and HQ, a reaction accelerator on the mechanical properties were investigated. With the increase of MN and HQ contents, impact property improved significantly but tensile property decreased.

• Environmental Analysis Health and Toxicology
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• v.18 no.1
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• pp.45-55
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• 2003

The alkylphenols, chlorophenols and bisphenol A were determined by gas chromatography/mass spectrom-etry-selected ion monitoring (GC/MS-SIM) mode followed by two work-up methods for comparison; isoBOC derivatization method and TBDMS derivatization method. Eleven phenols in paper samples were extracted with acetonitrile. Also, solid -phase extraction (SPE) with XAD -4 and subsequent conversion to isobutoxycarbonyl derivatives or tert.-butyldimethylsilyl derivatives for sensitive analysis with the selected ion-monitoring (SIM) mode. The SIM responses were linear with the correlation coefficient varying 0.9717 ∼ 0.9995 (isoBOC derivatization), and 0.9842 ∼ 0.9980 (TBDMS derivatization). The recoveries were 82.4 ∼ 108.8％) by area ratio of phenanthrene -d$\_$10/ vs bisphenol A-d$\^$l6/. (isoBOC derivatization and TBDMS derivatization) The range of concentrations was respectively, 0.95 ∼ 1.44 ng/g in 2,4-dichlorophenol, 1.01 ∼ 1.17 ng/g in t-butylphenol,2.17 ∼ 5.84 ng/g in pentachlorophenol, 12.68 ∼ 14.88 ng/g in nonylphenol and 30.84 ∼ 153.72 ng/g in bisphenol A.