• 한국환경성돌연변이발암원학회:학술대회논문집
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• 한국환경성돌연변이발암원학회 2003년도 추계학술대회
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• pp.118-118
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• 2003

• Toxicological Research
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• 제17권
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• pp.313-317
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• 2001

The Ministry of Health and Welfare of Japan has set up six research groups concerning the endocrine disrupting chemicals. One of these projects was "A study on development of testing methodology for health effects due to exposure of environmental endocrine disruptors". In this paper, three topics are described. In OECD collaboration for pre-validation of uterotrophic assay, the most sensitive response to ethnyl estradiol was noted in the ovarectomized rats treated subcutaneously for 7 days. Secondly, it was suggested that changes of the serum $\alpha_{2u}$-globulin level may be a sensitive parameter for detecting the estrogenic activities of chemicals. Finally, development of the sexually dimorphic nucleus of preoptic area in the brain oj male rats was inhibited by the treatment with estrogenic chemicals, and their masculine behaviors and reproductive abilities were impaired after sexual maturation. In conclusion, these parameters are considered to be sensitive endpoints for testing estrogenic chemicals.chemicals.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2003년도 춘계학술대회
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• pp.160-160
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• 2003

Plasma melatonin in the seasonal light-period is circadian rhythmically secreted. Maximal secretion showed at 14 o'clock in summer- and winter-like period, but minimal secretion showed at 5 o'clock in summer-like period and at 8 in winter-like period. These times of minimal secretions were at the beginning of light period. Plasma melatonin in the light period is secreted 62.5% more than in the dark period in summer-like period and 45.9% more in winter-like period. Total plasma melatonin in winter-like period is secreted 56.5% more than in summer-like period. The weights of testis(-20.8%) and body(-7.1%) were reduced in the winter-like period. By the increase of plasma melatonin in mice, body- and testis-weights are decreased, on the contrary by the decrease of plasma melatonin in mice, body and testis weights are increased. In view of the results so far achieved melatonin changes on the body weight and reproductive organ in mice. It is presumed that melatonin effects on the metabolism and sex hormone.

• 환경생물
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• 제21권4호
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• pp.352-357
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• 2003

Phenanthrene, one of Polycyclic aromatic hydrocarbons with three aromatic rings, is a ubiquitous contaminant in the environment. Phenanthrene has been identified in ambient air, drinking water and sediment. We examined the effect of phenanthrene on steroid hormones level of olive flounder, Paralichthys olivaceus. Plasma testosterone level was increased significantly in fish exposed to phenanthrene($\geq1.0 \mu M$) at 4th week. However, there was no significant changes of estradiol-17$\beta$ concentration in fish exposed to phenanthrene. The physiological variation in phenanthrene exposed fish was a dramatic increase in plasma cortisol level. It is concluded that chronic exposure of phenanthrene can induce increase of plasma testosterone levels and elevate the plasma cortisol level in flounder, Paralichthys olivaceus.

• Environmental Analysis Health and Toxicology
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• 제18권1호
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• pp.57-61
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• 2003

Plasma melatonin in the seasonal light-period is circadian rhythmically secreted. Maximal secretion showed at 14 o'clock in summer- and winter-like period, but minimal secretion showed at 5 o'clock in summer-like period and at 8 in winter-like period. These times of minimal secretions were at the beginning of light period. Plasma melatonin in the light period is secreted 62.5％ more than in the dark period in summer- like period and 45.9％ more in winter- like period. Total plasma melatonin in winter-like period is secreted 56.5％ more than in summer-like period. The weights of testis (-20.8％) and body (-7.1％) were reduced in the winter-like period. By the increase of plasma melatonin in mice, body - and testis -weights are decreased, on the contrary by the decrease of plasma melatonin in mice, body and testis weights are increased. In view of the results so far achieved melatonin changes on the body weight and reproductive organ in mice. It is presumed that melatonin effects on the metabolism and sex hormone.

• Journal of Forest and Environmental Science
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• 제34권1호
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• pp.50-52
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• 2018

The effect of basal nutrients concentrations and exogenous auxin for root induction from leaves of Sedum takesimense were investigated for mass-propagation. Root induction rates were significantly different from the concentrations of basal salts but not influenced by supplemented IBA in the medium. The lowest concentration of MS basal salts (1/10) was most effective to induce roots from leaves followed 1/5 MS, and 1/2 and full strength MS medium. Supplement of IBA $10{\mu}M$ in the medium did not improve the root induction that resulted no differences compare to the hormone free media. Rooted leaves were transplanted in soil and survived in greenhouse.

• Toxicological Research
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• 제26권4호
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• pp.237-243
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• 2010

Endocrine disrupting chemicals (EDCs) have been shown to interfere with physiological systems, i.e., adversely affecting hormone balance (endocrine system), or disrupting normal function, in the female and male reproductive organs. Although endocrine disruption is a global concern for human health, its impact and significance and the screening strategy for detecting these synthetic or man-made chemicals are not clearly understood in female and male reproductive functions. Thus, in this review, we summarize the interference of environmental EDCs on reproductive development and function, and toxicological mechanism(s) of EDCs in in vitro and in vivo models of male and female reproductive system. In addition, this review highlights the effect of exposure to multiple EDCs on reproductive functions, and brings attention to their toxicological mechanism(s) through estrogen receptors.

• Molecules and Cells
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• 제38권7호
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• pp.651-656
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• 2015

Plant growth and development are coordinately orchestrated by environmental cues and phytohormones. Light acts as a key environmental factor for fundamental plant growth and physiology through photosensory phytochromes and underlying molecular mechanisms. Although phytochromes are known to possess serine/threonine protein kinase activities, whether they trigger a signal transduction pathway via an intracellular protein kinase network remains unknown. In analyses of mitogen-activated protein kinase kinase (MAPKK, also called MKK) mutants, the mkk3 mutant has shown both a hypersensitive response in plant hormone gibberellin (GA) and a less sensitive response in red light signaling. Surprisingly, light-induced MAPK activation in wild-type (WT) seedlings and constitutive MAPK phosphorylation in dark-grown mkk3 mutant seedlings have also been found, respectively. Therefore, this study suggests that MKK3 acts in negative regulation in darkness and in light-induced MAPK activation during dark-light transition.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.186-186
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• 2001

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an environmental toxin that activates the aryl hydrocarbon receptor (AhR) and disrupts multiple endocrine signaling pathways by enhancing ligand metabolism, altering hormone synthesis, down regulating receptor levels, and interfering with gene transcription. And TCDD-mediated gene transactivation via the AhR has been shown to be dependent upon estrogen receptor (ER) expression in human breast cancer cells.(omitted)

• 환경생물
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• 제23권3호
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• pp.269-274
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• 2005

The 2D/E gel analysis for polypeptide expression reflecting I-18 C gene (early-ecdysterone inducible gene) has conducted the emerged C. riparius adults from larval phase exposure to tebufenozide acting as an ecdysteroidal molting hormone. Control group, the amount of ORE II of the I-18 C gene was larger than that of ORE I of this gene. After treatments, ORE I of the I-18 C gene was overexpressed as the polypeptide, whereas ORF II of this gene was expressed as the polypeptide and was clearly reduced expression. Accordingly, we consider that tebufenozide exhibited endocrine disruptions related processing of ecdysteroid receptor protein reflecting ORF II of I-18 C gene. Also, earlier emergence day was related overexpressed polypeptide reflecting ORE I of I-18 C gene. In this study result, tebufenozide induced changing of physiological condition, and then polypeptide expression reflecting early-ecdysterone inducible I-18 C gene was different between control group and exposure group.