• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.4
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• pp.574-580
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• 1998

Changes in plasma levels of thyroid and sex steroid Hormones were examined during maturation and parturition periods in rockfish (Sebastes schlegeli) cultured in net pens. Plasma L-thyroxine levels were $35.2{\pm}5.7\;ng/m{\ell}\;(n=\;5;\;mean\;{\pm}\;sem)$ at vitellogenesis stage and then significantly decreased to $20.5\;{\pm}\;4.2\;ng/m{\ell}$ at parturition stage (P<0.05), and rapidly returned to high level, $44.9{\pm}\;7.2\;ng/m{\ell}$ at resting stage. Plasma 3,5,3'-triiodo-L-thyronine levels were 12.9 $\pm$ 1.6 ng/ml at vitellogenesis stage, but significantly decreased to $3.7{\pm}0.7\;ng/m{\ell}$ at ovulation stage (P<0.05) and increased to $52.9{\pm}7.0\;ng/m{\ell}$ at jesting stage. Plasma estradiol-17 $\beta$ level showed the highest value ($4.3{\pm}0.9\;ng/m{\ell}$) at vitellogenesis stage, but the level significantly decreased to $0.3{\pm}0.1\;ng/m{\ell}$, during parturition stage (P<0.05). In vitellogenesis and ovulation stages, plasma testosterone levels were $1.8{\pm}0.3\;ng/m{\ell}$ and $2.1{\pm}0.7\;ng/m{\ell}$, respectively, thereafter the level significantly decreased to $0.1{\pm}0.1\;ng/m{\ell}$ at parturition stage (P<0.05). These findings suggest that thyroid hormones may have relation to maturation and parturition of mother rockfish.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.11
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• pp.1673-1685
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• 2019

Objective: To evaluate the efficacy of treatments based on gonadotrophin-releasing hormone (GnRH), GnRH-prostaglandin $F2{\alpha}$ ($PGF2{\alpha}$), and/or intense exposure to novel rams to induce fertile estrus without the use of steroid hormones in seasonally anestrous Suffolk ewes. Methods: In the first experiment, ewes were treated with one injection of GnRH, two injections of GnRH administered 7 days apart, or a sequence of GnRH-$PGF2{\alpha}$-GnRH (GPG). In the second experiment anestrous ewes were exposed, for 36 days starting on the day of weaning, to groups of four rams of three different breeds that were alternated every day. Besides exposure to the male effect (ME), the ewes were injected with saline solution (ME group, n = 20), with GnRH (ME-GnRH group, n = 20) or with a sequence of GnRH-$PGF2{\alpha}$-GnRH (ME-GPG group, n = 20). The rams used for male-effect were fitted with aprons to prevent mating, and ewes detected in estrus were bred to selected fertile rams. Ovarian activity was monitored by progesterone determinations in both experiments. Results: In the first experiment sustained induction of ovarian activity was not achieved and no ewe was detected in estrus. In the second experiment induction of sustained ovarian activity was achieved in all groups. Most of the ewes were detected in estrus, 76.7% of the ewes were mated during a 36-d breeding period and 71.7% of all the ewes became pregnant during that period. No significant differences between groups were found for any of these variables. However, estrus detection efficiency was higher in the ME-GnRH group than in the ME group (p<0.05). Conclusion: An intense male-effect, that included the continuous presence and frequent alternation of several rams of different breeds, was sufficient to induce ovarian activity and fertile estrus in Suffolk ewes during the period of deep anestrus without the use of hormones, although addition of GnRH improved the efficiency of estrus detection.

• Journal of Ginseng Research
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• v.21 no.3
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• pp.147-152
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• 1997

Ginsenosides $Rh_1$ and $Rh_2$ Induced the differentiation of F9 teratocarcinoma stem cells. These agents are structurally similar to the steroid hormones, therefore, we speculated that the steroid receptor (s) or novel nuclear receptor (s) could be involved in the differentiation process induces by them. Based on this speculation, we tried to alone new nuclear receptors with reverse transcription-polymerase chain reaction (RT-PCR) method by isolating RNA from F9 teratocarcinoma cells induced by ginsenosides. By using RT-PCR with degenerated primers from highly conserved DNA binding domain of nuclear receptors, we identified several nuclear receptors. In northern blot analysis we found that these clones are transcriptionally regulated by ginsenoside Rhl or Rh2 treatment. Further characterizations of these clones are needed to identify the mechanism of gene expression, which has an important role in the differentiation of F9 cells induced by ginsenosides.

• YAKHAK HOEJI
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• v.17 no.2
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• pp.92-102
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• 1973

Hormone이 암발생과 밀접한 관계가 있음은 이미 1935년대에 밝혀진 바 있다. 즉 lacassagne은 estrogen이 토끼 자궁벽의 fibromyomatous transformation에 영향을 준다고 하였다. Nelson는 guinea-pig를 시험동물로 해서 estrogen을 장기투여한 결과 uterine fibroids가 수발됨을 확인한 이래, 유발됨을 확인한 이래, 이러한 hormone이 암발생의 장기요인이 됨으리 밝히게 되었다. 이러한 업적은 Lipschutz에 의해 더욱 수식되었다. 이러한 업적의 결과가 여러편의 종설로 발표되었다. 즉 Lacassagne, Zuckerman, Burrows등, Gardner는 각기 종설을 발표하여 이를 확증하기에 이르렀다. 한편 각개 hormone, 그중에서도 sex-hormone의 opposite action은 Steinach등 및 Sand에 의해 밝혀졌고 거세백서에 estrogen을 투여했을때 유기되는 vaginal mucosa의 epidermization이 testosterone의 투여에 의해 급속히 소진됨을 Currier 일파가 증명하였고 estrogen에 의해 유발된 웅백서 부속성선의 조직변성이 androgen의 동시투여의 소실됨이 homone에 의해 유발된 neoplastic에 대해 유효하리하는 것은 백명한 일이고 이러한 사실은 현재 실시로 허다히 이용되고 있는 것이다.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2001.05a
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• pp.127-127
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• 2001

There is a concern that chemicals in our environment are affecting human health by disrupting a normal endocrine function. Much of the concern has focused on chemicals that can interact directly with steroid hormone receptors. The ability of certain man-made chemicals to mimic the effects of natural steroid hormones and their potential to disrupt the delicate balance of the endocrine system in animals are of increasing concern. (omitted)

• Clinical and Experimental Reproductive Medicine
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• v.38 no.4
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• pp.179-185
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• 2011

The ultimate function of the endometrium is to allow the implantation of a blastocyst and to support pregnancy. Cycles of tissue remodeling ensure that the endometrium is in a receptive state during the putative 'implantation window', the few days of each menstrual cycle when an appropriately developed blastocyst may be available to implant in the uterus. A successful pregnancy requires strict temporal regulation of maternal immune function to accommodate a semi-allogeneic embryo. To preparing immunological tolerance at the onset of implantation, tight temporal regulations are required between the immune and endocrine networks. This review will discuss about the action of steroid hormones on the human endometrium and particularly their role in regulating the inflammatory processes associated with endometrial receptivity.

• Advances in Traditional Medicine
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• v.9 no.4
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• pp.303-306
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• 2009

The defatted methanol extract of Raphanus sativus Linn. (Cruciferae) seed (MERS) was evaluated for its antisteroidogenic potential in mature female Swiss albino mice. The methanol extract at the doses of 100 and 200 mg/kg body weight significantly elevated the levels of cholesterol and ascorbic acid contents which serve as a precursor for the synthesis of steroid hormones in ovaries. The extract also significantly inhibited glucose-6-phosphate dehydrogenase and ${\Delta}^5-3{\beta}$-hydroxy steroid dehydrogenase, the two key enzymes involved in ovarian steroidogenesis. Hence the extract (MERS) exhibited significant antisteroidogenic activity.

• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.36-36
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• 1999

Bacterial Δ-3-ketosteroid isomerase (KSI) catalyzes the conversion of Δ-to Δ-3-ketosteroids via enolate formation, which is also found in the synthesis of all steroid hormones in mammals. In Pseudomonas testosteroni, KSI Asp38 (pKa ~ 4.7) was identified as the general base which abstracts the steroid C4b-H (pKa ~ 12.7) to form the dienolate intermediate.(omitted)

• Molecular & Cellular Toxicology
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• v.1 no.1
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• pp.52-61
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• 2005

Transcript profiling is a particularly valuable tool in the field of steroid receptor biology, as these receptors are ligand-activated transcription factors and therefore exert their initial effects through altering gene expression in responsive cells. Also, an awareness of endocrine disrupting chemicals (EDCs) and their potential screening methods to identify endocrine activity have been increased. Here we developed an in-house cDNA microarray, named KISTCHIP-400 ver. 1.0, with 416 clones, based on public database and research papers. These clones contained estrogen, androgen, thyroid hormone & receptors, sex hormone signal transduction & regulation, c-fos, c-myc, ps2 gene, metabolism related genes etc. Also, to validate the KISTCHIP-400 ver. 1.0, we investigated gene expression profiles with reference hormones, $10^{8}\;M\;17{\beta}-estradiol,\;10^{-7}\;M\;testosterone\;and\;10^{-7}\;M$ progesterone in MCF-7 cell line. As the results, gene expression profiles of three reference hormones were distinguished from each other with significant and identified 33 $17{\beta}-estradiol$ responsive genes. This study is in first step of validation for KISTCHIP-400 ver. 1.0, as following step transcriptional profile analysis on not only low concentrations of EDCs but suspected EDCs using KISTCHIP-400 ver. 1.0 is processing. Our results indicate that the developed microarray may be a useful laboratory tool for screening EDCs and elucidating endocrine disrupting mechanism.

• Applied Microscopy
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• v.23 no.1
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• pp.77-90
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• 1993

The mechanism by which blastocysts implant to uterine endometrium has not been clearly understood. In the present study, the following question was investigated: how are hormonal levels changed and how is uterine endometrium morphologically changed? Results obtained are as follows: Concentrations of serum estradiol and progesterone were significantly increased on day 4 and 5 of pregnancy. Uterine concentrations of PGE and $PGE_{2a}$ were sharply increased on day 1 and maintained similar concentrations thereafter, reaching the maximum on day 5. Both prostaglandins (PGs) concentrations were gradually decreased thereafter. Furthermore, concentrations of PGs in implant sites were greater than those in non-implant sites. PBR (pontamine blue reaction) in uterine endometrium was positive on day 6 of pregnancy, indicating that vascular permeability was increased. Edema and changes in structure of cell components were pronounced in stroma where PBR was developed. Moreover, these were more prominent in implant sites than non-implant sites. These results suggest that uterine PGs as well as steroid hormones increase during implantation in rats and these hormones might be involved in the process of implantation by modulating vascular permeability and the fine structures of uterine endometrial cells.