• Journal of Environmental Health Sciences
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• v.39 no.1
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• pp.1-18
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• 2013

Objectives: Although a great body of knowledge is available on the toxicity of bisphenol A (BPA), little is known about that of BPA alternatives, such as bisphenol analogues (BPs) or $Tritan^{TM}$ copolyesters. This review provides a summary of the available information on the toxicity of BPs and three components of $Tritan^{TM}$, with a special focus on endocrine disruption. Methods: We collected from the literature a battery of in vitro and in vivo assay data developed to assess endocrine disruption of four BPs (bisphenol AF, B, F, and S) and three major components of $Tritan^{TM}$ ((di-methylterephthalate (DMT), 1,4-cyclohexanedimethanol (CHDM), and 2,2,4,4-tetramethyl-1,3-cyclobutanediol (TMCD)). Results: Several alternative compounds were identified as possessing comparable or even greater endocrinedisrupting effects than BPA in in vitro and in vivo studies. Conclusions: Potential endocrine disruption of BPA alternatives requires further studies on health consequences in experimental animals and in humans following longer term exposure.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.5937-5946
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• 2012

The term endocrine disruptors is used to describe a variety of natural and manmade substances that have the capacity to potentially interfere with and modify the normal physiology of endocrine system either by mimicking, blocking or modulating the actions of natural endogenous hormones. The rising incidence of breast cancer over the last 50 years and the documented higher incidence in urban as compared to rural areas suggest a relationship to the introduction and increased use of xenoestrogens in our environment. The literature has developed over the last decades where initial experiments on endocrine disruptors did not support an involvement in breast cancer, and then evidence mounted implicating various environmental factors including hormones, endocrine disrupting chemicals and non-endocrine disrupting environmental carcinogens in the pathogenesis of breast cancer. Available data support the hypothesis that exposure to endocrine disruptors in utero leaves a signature on mammary gland morphogenesis so that the resulting dysgenic gland becomes more predisposed to develop tumors upon exposures to additional insults later on during life. Exceptionally, exposure to phytoestrogens could be beneficial to human health. Most of the available data are from well developed countries while the developing countries are still understudied regarding these issues. Here, we raise a note of caution about potential role of environmental toxins including endocrine disruptors in breast cancer development and call for serious measures to be taken by all involved parties in the developing world.

• Journal of Korean Biological Nursing Science
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• v.18 no.3
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• pp.160-168
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• 2016

Purpose: This study was conducted to examine the pro-environmental attitude (actual commitment domain, verbal commitment domain, affect domain), behavior to decreased exposure and knowledge of endocrine disruptors by obesity -related profiles (BMI, body fat percentage, visceral fat percentage, skeletal muscle mass percentage, waist circumference, waist-hip ratio). Methods: A cross-sectional study was conducted with 102 nursing students. Data were collected from November to December, 2015 using self-report questionnaires and physical measurements. Data were analyzed using t-test, Pearson correlation and coefficients with SPSS 18.0. Results: The study results showed that actual commitment domain of pro-environmental attitude and behavior to decreased exposure level on endocrine disruptors were significantly related to visceral fat percentage. Actual commitment domain of a pro-environmental attitude was significantly related to body fat percentage. Pro-environmental attitude was significantly related to the behavior to decreased exposure level on endocrine disruptors and knowledge thereof. Conclusion: These findings suggest that visceral fat and body fat percentages were significantly related to the actual commitment domain of a pro-environmental attitude. Therefore, a replication study is recommended to understand the connection between endocrine disruptors and obesity. In addition, developing an education program about endocrine disruptors for nursing students is recommended. In particular, a pro-environmental attitude, especially on actual commitment domain, could be involved as an education program.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.358-361
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• 2004

The photocatalytic degradation of Endocrine Discruptors, dibuthyl phthalate(DBP) has been investigated over TiO$_2$ photocatalysts irradiated with a ultraviolet (UV) light. The effect of operational parameters, i.e., reaction time, light intensity, pH and additive on the degradation rate of aqueous solution of Endocrine Discruptors has been examined. Results show that the employment of efficient photocatalysts and the selection of optimal operational parameters may lead to degradation of Endocrine Discruptors solutions.

• 대한생식의학회:학술대회논문집
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• 2005.06a
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• pp.111-111
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• 2005

• Environmental Analysis Health and Toxicology
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• v.20 no.4 s.51
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• pp.287-296
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• 2005

아연은 다양한 독성 물질로부터 유도된 아폼토시스를 저해하는 것으로 알려져 있으나 이 기전에 대해서는 명확히 밝혀지지 않았다. 본 연구에서는 인간 유방암 세포 MCF-7에 카드뮴을 처리하였을 때 유도되는 아폼토시스에 대한 아연의 저해효과를 살펴보았다. 아연의 아폼토시스 저해 효과는 DNA분절현상, 핵의 쪼개짐 그리고 caspase-9의 발현을 통하여 확인하였다. 또한 아연의 아폼토시스 저해효과가 카드뮴에 의한 산화적 스트레스와 관련이 있는지 확인하기 위하여 활성산소인 peroxide의 농도를 세포내에서 측정하였다. 나아가 superoxide dismutase (SOD), catalase (CAT) 그리고 glutahion redurtase (CR)같은 활성산소에 대한 인체내 방어기작으로 작용하는 항산화 효소의 활성을 측정하였다. 본 연구를 통해 아연이 카드뮴에 의해 생성된 세포내의 활성산소의 양을 감소시키고 항산화 효소를 회복시키는 기전이 카드뮴에 의한 아폼토시스를 저해하는 한 요인으로 사료되어진다.

• Journal of Environmental Health Sciences
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• v.41 no.3
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• pp.147-162
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• 2015

Objectives: The objective of this review was to summarize the primary role of three representative endocrine axes in aquatic vertebrates and discuss the effects on endocrine systems and their interactions in teleost fish after exposure to environmental contaminants. Methods: We summarized individual traits and mechanisms for hormonal and transcriptional interactions between the hypothalamic-pituitary-gonad (HPG), hypothalamic-pituitary-thyroid (HPT), and hypothalamic-pituitary-adrenal (HPA) axes in fish. We also provided a brief discussion on the effects of nonylphenol-induced toxicity on endocrine systems and their interactions in fish as a demonstration of holistic explanation. Results: Currently-available data showed that thyroid dysfunction is associated with reproductive toxicity due to changes in steroidogenic gene expressions and sex hormone levels as well as gonad glands in fish. As an example, we demonstrated that exposure to nonylphenol could induce estrogenicity in male fish by decreasing thyroid hormones, which contributes to increased aromatase expression. Although the mechanisms are complicated and involved in multiple ways, a number of studies have shown that sex steroids influence the HPT axis or the HPA axis in fish, indicating bi-directional crosstalk. Critically missing is information on the primary target or toxicity mechanisms of environmental contaminants among the three endocrine axes, so further studies are needed to explore those possibilities. Conclusions: This review highlights the interactions between the HPG, HPT, and HPA axes in fish in order to better understand how these endocrine systems could interact with each other in situations of exposure to endocrine disrupting chemicals.

• Animal cells and systems
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• v.4 no.2
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• pp.187-193
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• 2000

Regional distribution and relative frequency of endocrine cells in the pancreas of the red-eared slider, Trachemys scripta elegans, were investigated by immunohistochemical methods. Chromogranin (Cg) A-, serotonin-, insulin-, glucagon-, somatostatin-, bovine pancreatic polypeptide (BPP)- and human pancreatic polypeptede (HPP)-immunoreactive cells were identified in this study. Most of immunoreactive cells in the exocrine and endocrine pancreas (Langerhans islet) were generally spherical or spindle-shaped (open-typed cell), while occasionally cells round in shape (close-typed cell) were found in the basal portion or interepithelial regions of the pancreatic duct. These immunoreactive cells were located in the exocrine, endocrine pancreas and/or basal or interepithelial portion of the pancreatic duct. Serotonin-immunoreactive cells were found in the basal portion of epithelia of the pancreatic duct at a low frequency and interacinar region of the exocrine at a moderate frequency. Insulin-immunoreactive cells were found in the central portion of the endocrine pancreas, interacinar regions of the exocrine pancreas and basal portion of the epithelia of the pancreatic duct at high, moderate and low frequencies, respectively. Glucagon-immunoreactive cells were detected in the periphery of the endocrine pancreas, interacinar region of the exocrine pancreas and basal portion of the epithelia or interepithelia of the pancreatic duct at high, moderate and moderate frequencies, respectively. Somatostatin-immunoreactive cells were dispersed in the whole area of the endocrine pancreas, interacinar regions of exocrine pancreas and basal portion of the epithelia or interepithelia of the pancreatic duct at a moderate frequency. BPP- and HPP-immunoreactive cells were detected in the iinteracinar region of the exocrine pancreas at moderate and hige frequencies, respectively. However, no Cg A- and motilin-immunoreactive cells were detected in this study.

• Environmental Analysis Health and Toxicology
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• v.21 no.3 s.54
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• pp.291-299
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• 2006

The experiments investigated whether early exposure to testosterone propionate (TP) during prepuberty alters testis development in Sprague-Dawley male rats. We performed Hershberger assay using the stimulated weanling male rats by OECD protocols, cDNA microarray, and Western blot. TP was subcutaneously injected to uncastrated Sprague-Dawley male rat of 22 days old for 10 consecutive days at doses of 0.4, 0.8, 1.0, 1.2, 1.6 mg/kg per day. At necropsy, the following tissues were removed and weighed: combined testes, epididymides (Epi), Cowper's glands (COW), levator am, and bulbocavernosus muscles (LABC), seminal vesicles, together with coagulating gland (SV) and ventral prostate (VP). We found that TP increased the weights of Epi, VP, SV, COW, and LABC, while testis was decreased in a dose-dependent manner. In cDNA microarray analysis of testis, there were significant reductions in the expression of cytochrome P450 11A (CYP11A), the rate-limiting enzyme of steroidogenesis. Taken together these results, TP exposure before puberty in male rats may produce the delay in testis development by inhibiting the CYP11A gene expression.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.132-132
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• 2002

Effects of antioxidant vitamins were investigated in di(2-ethylhexyl) phthalate (DEHP)-induced endocrine disruption toxicity. After rats were treated with DEHP, and vitamin C and vitamin E were supplemented for 30 days.(omitted)