• Development and Reproduction
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• v.16 no.1
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• pp.9-18
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• 2012

The effects of the estrogenic compound 4-nonylphenol (4-NP) on vitellogenesis in juvenile olive flounder ($Paralichthys$ $olivaceus$) and rockfish ($Sebastes$ $schlegeli$) exposed continuously at 10, 50 and $100{\mu}g{\ell}^{-1}$ levels for 7 days were compared. The expression of VTG mRNA level and protein using specific probes were examined. The levels of plasma estradiol-17 ${\beta}(E_2)$ and testosterone (T) were assessed by radioimmunoassay (RIA). Plasma $E_2$ concentrations increased significantly in two female fish species exposed to $100{\mu}g{\ell}^{-1}$ of 4-NP over concentrations in control fish. Plasma T concentrations increased in $P.$ $olivaceus$. Four days after exposure, the level of VTG mRNA expression increased in $P.$ $olivaceus$ and $S.$ $schlegeli$ exposed to $20{\mu}g{\ell}^{-1}$ of 4-NP. In addition, plasma VTG protein expression was seen in $P.$ $olivaceus$ and $S.$ $schlegeli$. In $S.$ $schlegeli$ and $P.$ $olivaceus$ exposed to 4-NP, the changes were noticed mainly in hepatocytic vaculation after 7 days of exposure. Thus, 4-NP may disrupt vitellogenesis in immature fish both directly and indirectly via disrupted steroidogenesis and liver pathology. Immature $S.$ $schlegeli$ were the most sensitive to 4-NP exposure in vitellogenesis.

• Reproductive and Developmental Biology
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• v.30 no.1
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• pp.7-11
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• 2006

This study was conducted to examine the effects of hormone and sodium pyruvate on in vitro maturation of canine oocytes. Canine oocytes were collected from the ovaries of dogs and cultured in NCSU-37 medium with hormones and sodium pyruvate for 72 hr. Oocytes matured to the metaphase II (MII) stage were observed only from estradiol $17{\beta}\;(E_2)$, and the presence of gonadotropin did not improve the nuclear maturation. No oocytes were developed to the MII stage when $E_2$ was added to medium during the first 6 and 24 hrs of culture period. The presence of $E_2$ during the whole culture period enhanced the nuclear maturation to the MII stage (6.0%, P<0.05). High concentration of sodium pyruvate (2.5 mM) slightly enhanced the nuclear maturation to the metapahse I (HMI) stage, but not the MII stage. the result of the present study shows that the presence of $ E_2$ during the whole culture period of 72 hr enhances the maturation of canine oocytes to the M stage, but sodium pyruvate does not affect the nuclear maturation of the canine oocytes.

• Journal of Embryo Transfer
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• v.14 no.2
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• pp.113-119
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• 1999

This study was performed to improve the development of the in vitro fertilized bovine embryos by the condition of in vitro maturation. COCs were matured in TCM 199 supplemented with 0.1% PVA, 10ng/ml EGF, Hormones (5$\mu\textrm{g}$/ml FSH, 10 IU hCG, 1 $\mu\textrm{g}$/ml estradiol 17-$\beta$) or granulsa cell+Hormones atmosphere 39$^{\circ}C$, 5% CO2, 95% air for 24hrs. Matured oocytes were fertilized with frozen-thawed semen capacitated with 5mM caffein in BO medium for 20 hrs. IVF embryos were cultured in TCM 199 containing with hormones(same as matured medium), 10% FBS and co-culture with bovine oviduct epitherial cells. Maturation rates of COCs were showed 73.8%, 78.5%, 83.2% and 87.6% respectively, and were significant differences between PVA, EGF, and Hormones, GC+Hormones(p<0.05). The cleavage rates of IVF embryos were revealed 72.5%, 78.4%, 82.3% and 84.2% and showed same tendency as maturation rates(p<0.05). The blastocysts matured by above maturation condition and cultured for 7~10 days after fertilization had 34.4, 43.6, 52.3 and 59.3 cells had no differences among the treatments. These results suggest that high molecules as a substitutes of serum and growth factor may induce nuclear resumption of COCs but we need more study to produce transferable IVF blastocysts by use of that agents.

• Journal of Embryo Transfer
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• v.11 no.1
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• pp.7-14
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• 1996

The object of this study was to evaluate the effect of uterine epithelial cells on development of Korean native cattle(KNC) oocytes fertilized in vitro. Qocytes were collected from ovaries of slaughtered Korean Native Cows and matured in TCM199 with granulosa cells supplemented with 10% FBS, 5$\mu$g/ml FSH, 10 JU/ml hCG, and 1$\mu$g/ml estradiol-17$\beta$ for 24 hrs. For co-culture of in vitro development of fertilized ova, oviductal epithelial cells (l$\times$l0˚cells /ml) obtained from slaughtered cow and uterine epithelial cells(1$\times$10˚cells /ml) flushed from the superovulated holstein on Day 7 were incubated in 39$^{\circ}C$, 5% $CO_2$, 95% air. Frozen-thawed KNC sperm was capacitated with BO(Brackett & Oliphant, 1975) medium supplemented with 10mM, 5mM-caffein. Matured oocytes were inseminated for 20 hrs. And then fertilized oocytes were washed with culture medium and transferred to oviductal epithelial cells for in vitro development and three days later a portion of embryos were transferred to uterine epithelial cells. Stastical methods of developmental rates on KNC-IVF oocytes was ANOVA-test. Developmental rates of KNC-IVF oocytes was significant higher(P<0.01) when co-cul-tured with uterine epithelial cells(25.2%) than oviductal epithelial cells. Blatocyst cul-tured for 7 to 9 days were frozen by automatic freezer with 1.4M glycerol-PBS. Survival rates of blastocyst was 40.0%. Fourteen frozen-thawed blastocysts were transferred to five holstein heifers on day 7 after natural estrus. Three recipients were observed twin and one recipient was single by ultra-sound systems on days 45 after embryo transfer.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.5
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• pp.474-481
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• 2010

The sperm collection time, sex steroid hormones, and gonadal development of protandrous black porgy, Acanthopagrus schlegeli, acclimated in freshwater for more than 2 years were investigated to evaluate its reproductive capability. The gonadal development of black porgy reared in seawater and freshwater could each be classified into four successive stages. For black porgy reared in seawater (BSW) as the control, these were the growing (December to February), mature (February to March), spent (March to June), and degeneration and resting (July to December) stages; for black porgy reared in freshwater (BFW), these were the growing (November to January), mature (January to February), spent (February to May), degeneration and resting (June to November) stages. In both BSW and BFW, the plasma cortisol levels were the highest in March. The plasma testosterone (T) levels of BSW and BFW were the highest in March and February, respectively. The plasma estradiol-$17{\beta}$ ($E_2$) levels did not differ significantly between BSW and BFW. The 11-ketotestosterone (11-KT) levels in the plasma of BSW and BFW were the highest in April. Sperm was collectible from March to June in BSW and from February to May in BFW. The results indicated that the gonadal maturation of BFW was about 1 month faster than that of BSW.

• Animal cells and systems
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• v.16 no.6
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• pp.469-478
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• 2012

Sex hormones have long been considered to play an important role in bone turnover rate, periodontal diseases, and wound healing. We have studied the effect of porcine testis steroid extract (PTSE), an extract of porcine testes, which holds a good ratio of 19-nortestosterone (nandrolone), testosterone, androstenedione, $17{\beta}$-estradiol, and estrone, on the healing rate of a standardized full-thickness linear wound on the back of the rat. Skin punch or carbon dioxide ($CO_2$) laser methods were used to create the deep skin injury in two groups of animals. The animals were treated with the PTSE cream, control cream and Vaseline (control) to find out the effect in re-epithelialization, contraction, and formation of granulation and scar tissues. Histological examination after 21 days showed 100, 87.4, and 80.5% recovery of epidermis, dermis, and hypodermis, respectively in the PTSE-treated animals. Similarly, on the 15th day of treatment, complete healing of intact skin was observed in the PTSE cream-treated animals among the laser radiation group. Even though the beginning of re-epithelialization phase and completion of serum crust formation was also observed in the base cream- and Vaseline-treated animals respectively, the complete healing cycle was observed only in the PTSE-treated group. The white blood cell count in the PTSE-treated group showed that PTSE cream is nontoxic to animals.

• Animal cells and systems
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• v.7 no.3
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• pp.227-235
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• 2003

Bisphenol A (BPA), nonylphenol (NP), and 4-tert-octylphenol (OP) are known endocrine disrupting chemicals (EDCs) with estrogenic activity in fish. This study compared the effects of BPA, NP and OP on in vitro vitellogenin (VTG) synthesis in primary cultures of hepatocytes of the Chinese minnow Phoxinus oxycephalus. The VTG secreted into the culture medium was measured using enzyme-linked immunosorbent assay (ELISA), which we developed in this study using an antibody prepared from homogenates of Chinese minnow egg. VTG synthesis was induced by estradiol-17$\beta$ ($E_2$) and phenols (BPA, NP and OP) treatment. $E_2$ at concentrations of 10$^{-6}$ M or higher increased VTG levels significantly (P < 0.05). Exposure to 10^5\;M\;BPA\;or\;10^-4$M NP and OPinduced in vitro VTG synthesis (P < 0.01). However, $10^-3$ M BPA, NP or OP did not induce VTG synthesis. These results suggest that SPA has the highest estrogenic potential in Chinese minnow hepatocytes. Tamoxifen, an anti-estrogen, drastically blocked the production of VTG by phenols (BPA, NP and OP) suggesting that phenols (BPA, NP and OP) may act via binding to estrogen receptor (ER) in Chinese minnow hepatocytes.

• Ocean and Polar Research
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• v.38 no.1
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• pp.81-88
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• 2016

In many fish species, including Nile tilapia (Oreochromis niloticus), gonadal development occurs at the expense of stored energy and nutrients. Therefore, reproductive systems are inhibited by limited food supply. It has been well established that reproductive function is highly sensitive to both metabolic status and energy balance. Nothing is known about the possible mediated connection between energy balance and reproduction. Kisspeptin, a neuropeptide product of the Kiss gene has emerged as an essential gatekeeper of reproduction and may be possibly be linked to energy balance and reproduction in non-mammalians. Thus, in this study, the effect of fasting (10 days) on the expression of kisspeptin and the gonadotropin-releasing hormone (GnRH) gene were assessed in Nile tilapia (male and female) using qRT-PCR. In addition, plasma levels of estradiol-$17{\beta}$ ($E_2$) and 11-ketotestosterone (11-KT) in adult tilapia were measured by ELISA. In male tilapia, fasting reduced Kiss2 and GnRH I mRNA expression in the brain and 11-KT level in comparison with the fed tilapia (p < 0.05). In females, however, there were no significant differences in GnRH I mRNA expression and $E_2$ between fish subjected to fasting and those fed (p > 0.05). These data indicate the impact of nutritional states on kisspeptin as a potential regulatory mechanism for the control of reproduction in male Nile tilapia.

• Fisheries and Aquatic Sciences
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• v.8 no.4
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• pp.213-219
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• 2005

Vitellogenin (VTG) was purified from the blood plasma of estradiol-17$\beta$ ($E_2$)-treated male marbled sole (Limanda yokohamae) using gel filtration and anion exchange chromatography. The purity of the marbled sole VTG (msVTG) was confirmed by polyacrylamide gel electrophoresis (SDS-PAGE) and N-terminal amino acid sequencing. The purified msVTG was used to produce monoclonal and polyclonal antibodies in mice and rabbits, respectively, and the specificity of the polyclonal antisera for msVTG was confirmed by Western blot analysis. The antibodies cross­reacted with a protein of molecular mass approximately 160 kDa in the plasma samples of mature female marbled sole. No cross-reactivity was observed with the plasma of male fish. A direct non-competitive sandwich enzyme-linked immunosorbent assay (ELISA) was developed using the monoclonal anti-msVTG and polyclonal anti-msVTG antibodies, with purified msVTG as the standard protein. The values of the intra- and inter-assay variations were within the ranges of $8.l-9.8\%$ and $8.5-12.2\%$, respectively. The sensitivity was about 0.3 ng/mL. Serial dilutions of plasma from mature female sole reacted with the msVTG-antibodies in the sandwich ELISA, whereas the plasma from male fish did not. The results indicate that the maturation status of female marbled sole can be identified using a sandwich ELISA for msVTG.

• Fisheries and Aquatic Sciences
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• v.15 no.3
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• pp.221-231
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• 2012

The marine medaka Oryzias dancena choriogenin H gene (odChgH) and its mRNA expression during estradiol-$17{\beta}$ (E2) exposure were characterized. At the amino acid level, the choriogenin H protein is predicted to possess the conserved repetitive N-terminal region, as well as zona pellucida (ZP) and Trefoil factor family (TFF) domains. At the genomic level, odChgH has an eight-exon organization with a distribution pattern of transcription factor binding sites in the 5'-upstream region, which is commonly found in other estrogen-responsive genes. The tissue distribution pattern of odChgH mRNA was found to be gender-specific, whereby females showed a higher expression level and wider tissue distribution than did males. During embryonic development, odChgH mRNA was robustly detected from the stage of visceral blood vessel formation. Experimental E2 exposure of males resulted in odChgH mRNA being induced not only in the liver, but also in other several tissues. The E2-mediated induction was fairly dose-dependent. The basal expression levels of hepatic odChgH mRNA were lower in males that were acclimated to 30 ppt salinity than in those acclimated to 0 or 15 ppt salinity. In contrast, the inducibility of odChgH mRNA during E2 exposure was greater in seawater-acclimated fish than in brackish water- or freshwater-acclimated fish.