• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2002.11a
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• pp.149-149
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• 2002

Epidemiologically the incidence of liver cancer is markedly sex-differentiated, with a much higher frequency in men than in women. In experimental animals, it is also higher in male than in female irrespective of carcinogen-induced or spontaneous tumors. Therefore, we tried to investigate the modulating effects of sex hormones in experimental hepatocarcinogenesis. For induction of liver tumors, mini-osmotic pump containing diethylnitrosamine at a dose level of 47.5mg was implanted into the peritoneal cavity of the rat at 6 weeks old. To remove the effects of male sex hormones, the animals of group 2 were castrated one week prior to DEN treatment. To see the effects of estrogen, pellet containing 1g or 10g of estradiol-3-benzoate was infused subcutaneously to the animals of group 3 and 4 one week prior to DEN treatment. The pellets were exchanged every 4 weeks until sacrifice. All animals were sacrificed at 26 weeks after DEN treatment. The tumor incidences in group 1 (DEN alone), group 2 (DEN +castration), group 3(DEN +EB 1g) and group 4 (DEN +EB 10g) were 100％ (15/15), 93.3％ (14/15), 85.7％ (12/14) and 66.7％ (10/15), respectively, showing that the value of group 4 is significantly different from that of group 1. Tumor multiplicity data of group 1, 2, 3 and 4 were 5.470.73, 2.800.51, 2.070.41 and 1.670.46, respectively, showing castration or EB treatment reduced number of liver tumors significantly (P<0.001). With immunohistochemistry and Western blotting of ER the expressions were detected in normal adjacent liver cells but decreased or lost in tumor cells. From these results we conclude that female sex hormone, especially estrogen, may act as a liver tumor suppressor, and it seemed that the down regulation of ER may be associated with liver tumor development.

• Journal of Embryo Transfer
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• v.26 no.3
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• pp.219-222
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• 2011

Eight female Himalayan tahrs (Hemitragus jemlahicus) were estrus-synchronized, and transcervically inseminated with frozen-thawed semen in September, 2009, about 2 to 3 months earlier than their natural breeding season. Intravaginal progesterone-releasing devices were inserted into vaginas of six Himalayan tahrs on September 7, and the other two on September 8 to suppress luteal function of ovaries. The devices had been placed deep inside the vagina prior to withdrawal on September 23. A day before CIDR removal, a combination of PMSG 400 IU and hCG 200 IU was intramuscularly injected. Forty hours later, frozen-thawed semen was transcervically inseminated. Pregnancy diagnosis was performed 39 days later by analyzing progesterone level of serum. Every treatment was done under anesthesia inducted by xylazine injection. In conclusion, vaginal discharge of cervical mucus, hormonal changes induced by implant-typed or muscularly injectable hormones and widening of cervix enough to insert an insemination gun into uterine body were achieved in non-breeding season. Moreover, the first inseminated Himalayan tahr, 36 hours after CIDR removal was assumed to be pregnant but the fetus may have been lost due to the use of anesthetic drug.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.1
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• pp.173-181
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• 1992

Duck is an important domestic animal, especially in Asia. Eighty five percent of ducks in the world are kept in Asia, especially in the East and South Asia regions. The ancestor of domesticated ducks was mallard (Anas platylhynchos), which are still migrating between north and southern parts in Eurasia. Ducks have been domesticated in China for at least 3000 years ago. Phylogenetic studies on ducks, employing electrophoresis of blood proteins, indicate a marked difference of genetic constitution between duck breeds in southeast Asia and those in northeast Asia. Duck embryonic ovary is much more active in secretion of sex steroid hormones especially estradiol than the embryonic testes. Estradiol secreted by the embryonic left ovary has an important role in female sexual differentiation in ducks. In the female ducks, plasma LH, estradiol and testosterone levels increase and reach peaks shortly before the first egg, while progesterone level reach a peak shortly after the first egg. In laying ducks oviposition mostly occurs in the last 3 hr of darkness and first hr of light ranging 02:00-06:00 under 14 hr light (05:00-19:00) and 10 hr darkness photoperiodic condition. Measurements of plasma hormone levels reveal that onset of darkness is a major signal for LH release from the pituitary and the subsequent release of progesterone from ovary, and for induction of ovulation in the female duck.

• Journal of Nutrition and Health
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• v.38 no.3
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• pp.203-210
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• 2005

Many young women suffer from premenstrual syndrome (PMS). The purpose of this study was to examine the effect of isoflavone on serum sex hormone and PMS during the luteal phase of the menstrual cycle. We investigated the incidence of PMS in 116 Korean female college students. The incidence of PMS was $19.8\%$. Among them, 9 PMS and 13 control were given 90 mg isoflavone per day during 2 menstrual cycles. The changes in anthropometric measurements, dietary intakes, serum parameters including sex hormones, and PMS symptoms were observed. Isoflavone supplementation did not affect anthropometric measurements. However, SBP and DBP were significantly decreased in control. Dietary intakes were not changed after supplementation of isoflavones. Serum SHBG was lower in PMS group than in control and significantly decreased in control with isoflavone supplementation. PMS symptoms such as backache, sweet, salty, and fatty food craving, coffee/tea drinking, and anxiety were significantly lessened. Based on these results, isoflavone supplementation may benefit young women by reducing some of PMS. Further studies of soy isoflavones effect on sex hormone and PMS may help to prepare for PMS management.

• Analytical Science and Technology
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• v.7 no.2
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• pp.141-147
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• 1994

The adsorptive stripping voltammetry of corticosterone was studied in $1.0{\times}10^{-2}M$ sodium hydroxide as supporting electrolyte. The analytical conditions were as follow : 360 sec. for deposition time, -8.0 volts deposition potential, medium size mercury drop, and 20mV/sec scan rate. Calibration curve has shown a linearlity in the range of $5.0{\times}10^{-9}M$ to $8.0{\times}10^{-7}M$ and the detection limits have been $9.5{\times}10^{-10}M$ for corticoterones. This method has shown such a high sensitivity even in dilute solution that has been useful for analyzing sex hormones in medical supplies without interference of additives.

• Development and Reproduction
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• v.18 no.4
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• pp.293-300
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• 2014

Direct cell-cell communication through connexin (Cx) complexes is a way to achieve functional accordance of cells within a tissue or an organ. The initial segment (IS), a part of the epididymis, plays important roles in sperm maturation. Steroid hormones influence on expression of a number of genes in the IS of adult animals. However, developmental effect of sex hormones on the gene expression in the IS has not been examined. In this study, estradiol benzoate (EB, an estrogen agonist) or flutamide (Flu, an androgen antagonist) was exogenously administrated at 1 week of postnatal age, and expressional changes of Cx genes in the IS were determined at 4 months of age by a quantitative real-time PCR analysis. Treatment of EB at $0.015{\mu}g/kg$ body weight (BW) increased expression of Cx30.3, 31.1, and 43 genes. However, treatment of 1.5 mg EB/kg BW resulted in expressional decreases of Cx31, 32, and 45 genes and caused increases of Cx30.3 and 43 gene expression. Significant decreases of Cx31, 31.1, 32, 37, and 45 gene expression were detected with a treatment of $500{\mu}g\;Flu/kg$ BW, while expression of Cx43 gene was significantly increased with a treatment of $500{\mu}g\;Flu/kg$ BW. A treatment of $50{\mu}g\;Flu/kg$ BW led to significant increases of Cx30.3, 32, 37, 40, and 43 gene expression. These findings imply that exogenous exposure of steroidal hormones during the early developmental period would result in aberrant expression of Cx genes in the adult IS.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.62-67
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• 2019

We studied the effect of several sex-related steroid hormones (serotonin, progesterone and ${\beta}$-estradiol) for 6 days on the induction of sexual reproduction for the mass production of resting eggs in the marine rotifer Brachionus rotundiformis. The highest mix rate of 20.6% appeared with the ${\beta}$-estradiol ($E_2$) treatment on the third day. The number of resting eggs was highest with $E_2$ treatment, followed by that of the serotonin treatment group. In addition, we investigated the effect of the hormones on the expression pattern of the genes related to sexual reproduction in the rotifer. NrbP, SRY, Cyclin and MrpmB genes were up-regulated with all the hormone treatments. As a result, ${\beta}$-estradiol was more effective than the other hormone treatments to produce resting eggs in B. rotundiformis. We suggest that the sexual reproduction-related genes in the rotifer are the NrbP, SRY, Cyclin and MrpmB genes. Further study is required to determine the optimum concentration of $E_2$ for the effective production of resting eggs in the rotifer.

• Development and Reproduction
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• v.16 no.4
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• pp.279-287
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• 2012

We investigated the changes in plasma sex steroid hormones, testosterone (T), estradiol-$17{\beta}$ ($E_2$), 17,$20{\beta}$-dihydroxy-4-pregnen-3-one ($17{\alpha}20{\beta}P$), 11-ketotestosterone (11KT) and cortisol levels from ribbed gunnel, Dictyosoma burgeri in associated with annual reproductive cycle. The gonadosomatic index (GSI) of females increased from November, peaked in February and decreased rapidly from March. The GSI of males also increased from November, peaked in January and then decreased gradually. In females, $E_2$ levels increased and remained high from December to February. The levels of T showed a similar tendency and correlated ($r_s$=0.898, p<0.01) with $E_2$ levels. The levels of $17{\alpha}20{\beta}P$ increased rapidly in February ($4.78{\pm}1.01ng/ml$) and peaked in July ($5.08{\pm}0.65ng/ml$). Cortisol level was peaked in March and correlated with $17{\alpha}20{\beta}P$ levels ($r_s$=0.696, p<0.01). In males, the levels of T was peaked in January and then decreased rapidly. The levels of 11KT were remained high from October to January. On the other hand, the levels of $17{\alpha}20{\beta}P$ fluctuated during reproductive cycle. These results suggest that plasma sex steroids in ribbed gunnels have annual periodicity, and that cortisol may involve in maturation of females.

• Animal cells and systems
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• v.11 no.2
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• pp.117-124
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• 2007

The present study demonstrates the changes in body weight (BW) and plasma sex steroid hormone profiles during artificial maturation induced by human chorionic gonadotropin (HCG) or salmon pituitary extract (SPE) injections in cultured eel, Anguilla japonica, kept in seawater for 3 months. In the weekly SPE-injected female group, BW was relatively stable during vitellogenesis. Following induction of vitellogenesis, females exhibited a rapid increase of BW, and the oocytes were observed to be in the migratory nucleus stage at the end of the experiment. Plasma testosterone (T) and $estradiol-17{\beta}$ ($E_2$) levels increased slightly during vitellogenesis and peaked at an average of 5.82 ng/mL and 4.76 ng/mL, respectively, at the end of the experiment. In the weekly control and HCG-injected female groups, BW slowly decreased during the experimental period, and the oocytes of the two groups were observed to be at the primary yolk globule stage. In the weekly HCG-injected female group, plasma T and $E_2$ levels increased slightly during vitellogenesis and decreased afterward. In the control female group, however, plasma T and $E_2$ levels were not altered during the experimental period. Furthermore, plasma $17{\alpha},20{\beta}-dihydroxy-4-pregnen-3-one$ (DHP) was not detected in all experimental groups. Fertility and hatching rates of SPE-injected females were significantly higher in those that ovulated 15 h after DHP injection than 18 h. These results indicate that long rearing in seawater increases responsiveness to SPE in ovarian maturation of the Japanese eel, resulting in shortened period from completion of vitellogenesis by sex steroid hormone production.

• Reproductive and Developmental Biology
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• v.37 no.4
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• pp.199-203
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• 2013

This experiment was conducted to investigate the genetic effects of candidate genes on the growth of spleen and liver tissues using dietary Curcuma longa (C. longa) supplementation. Expression analyses of candidate genes regarding animal growth was performed in order to determine the factors affecting the growth related to immune components of Curucumin, Turmerone, and Zingiberene as the bile secretion Paratolyl methyl carbinol (PTMC). The animals were divided into four groups of five chicks supplied with experimental diets of C. longa at 0.25, 0.5 and 1% and controls. The 19 growth-related genes were known to cell maturation, differentiation significant expression patterns in this analysis. Expression of growth response-related genes in chicks supplemented with 1% of C. longa showed better growth performance than chicks with 0.25 and 0.5% in spleen (p<0.05). The IGF1, MSTN, POU1F1, ADCYAP1 gene were known to central roles in mediating gonadotropin function, regulating steroidogenesis and promoting oocyte growth and maturation. Sex steroids, androgen and estrogen can affect sex differentiation and also can affect muscle development. On the other hand, GHSR and FABP3 gene showed significant expression patterns in this analysis. The results would be used as basic information for the variation of growth-related genes expression on the cell growth, sex cell growth, and sex hormones according to dietary supplementation with C. longa in chickens.