• Fisheries and Aquatic Sciences
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• v.26 no.1
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• pp.48-57
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• 2023

One of the ways to increase the production for aquaculture is through the cultivation of monosexuals by ensuring genital reversal from which energy for reproduction is diverted towards growth. Masculinization has been identified as one of the most prominent techniques, where sex development was directed from female to male. This approach only altered the phenotype and not the genotype. The red claw crayfish (Cherax quadricarinatus) was a relatively new commercial commodity, and the males were known to grow faster than females. Hence, it was proposed to use monocultures comprising an all-male population to increase yield using steroid hormone, synthetic 17α-methyltestosterone. However, this technique generated residues that detrimentally affect human health, the environment, and cultivated organisms. Therefore, finding new safe natural steroid sources was essential, and one of which is exploring of natural hormones extracted from the viscera of sea cucumbers (Holothuria scabra Jaeger). This study focused on the determination of male formation and testosterone levels among juvenile crayfish, after immersing in sea cucumber steroid extract (SCSE). A completely random design with factorial was used with two variables, encompassing the varied doses (0, 2, 4 mg/L, 2 mg/L 17α-methyl testosterone as control group) and immersion times of 18 and 30 h. The result showed the dose-dependent ability of SCSE increase the male genital formation and promote the testosterone level of juvenile crayfish. In addition, the testosterone was influenced by dose and immersion duration time, with the highest level of testosterone observed in treatments of 4 mg/L SCSE with 30 h immersion was 0.248 ng/mL, while the male percentage was 77%. In conclusion, the combination of dose and immersion time significantly affected growth and testosterone levels.

• Clinical and Experimental Reproductive Medicine
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• v.27 no.4
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• pp.359-366
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• 2000

The present studt was performed to investigate the effect of treatment and samples of human follicular fluid (hFF) on the development in vitro of mouse embryos. The two cell stage embryos collected at 40 h post-hCG injection were cultured in the modified human tubal fluid (m-RTF) containing 15% synthetic serum substitute (SSS) or human tubal fluid (hFF) for up to 3 days at $37^{\circ}C$ in 5% $CO_2$ incubator. Also the composition of hormone, total protein and protein pattern of hFF samples were analyzed. The developmental rate of mouse embryos developed to blastocyst were not significant difference in the m-RTF containing 15% hFF filtered with 0.22 or 0.8 ${\mu}m$ syringe filter, however, the embryos cultured in the m-RTF containing inactivated hFF were significantly (p<0.05) developed at the high rate to blastocyst than those containing fresh hFF and SSS. The in vitro developmental rate to blastocyst and hatched blastocyst in the m-RTF containing 15% hFF sample A (90.5 and 85.4%, respectively) and SSS (79.4 and 75.3, respectively) were significantly (p<0.05) increased, compared with hFF sample B (64.2 and 54.1 %, respectively). The hFF sample A tended to be higher concentration of LH, FSR, total protein and the ratio of progesterone/$E_2$ and lower concentration of $E_2$ and progesterone than the hFF sample B, but there were no differences in the protein pattern between the two hFF samples. The results of these study suggest that the addition of hFF to the culture medium enhances the development in vitro to blastocyst and hatched blastocyst, but the in vitro developmental rate of mouse embryos is different between hFF samples.

• Clinical and Experimental Reproductive Medicine
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• v.30 no.1
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• pp.47-55
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• 2003

Objectives: Bok, Bcl-2-related ovarian killer, is a proapoptotic Bcl-2 family protein identified in the ovary based on its dimerization with the antiapoptotic protein Mcl-1. The present study examined the hormonal regulation and localization of Bok messenger RNA levels in the mouse ovary during the follicle development. Methods: The animals were implanted subcutaneously with Silastic brand capsules containing the synthetic estrogen, DES at $21{\sim}23$ days of age. Ovaries were collected $1{\sim}3$ days after implantation for RNA analysis and in situ hybridization. Some mice were removed capsule for $1{\sim}2$ days to induce ovarian follicle apoptosis. Ovaries were also collected from 26 day-old immature mice at various times after treatment with 10 IU PMSG. Some mice received a single intraperitoneal injection of 10 IU hCG to induce ovulation, and ovaries were obtained at different time intervals for Northern blot and in situ hybridization analysis, respectively. Results: Treatment of immature mice with diethylstilbestrol (DES) for $24{\sim}48$ h increased ovarian Bok mRNA levels. Bok mRNA was remained the same levels in mice removed DES for $24{\sim}48$ h to induce apoptosis. High signals of Bok mRNA after DES treatment were detected in granulosa cells of early antral follicles. Treatment of immature mice with PMSG for 12 h increased markedly ovarian Bok mRNA expression which was detected mainly in preantral and atretic follicles. Interestingly, low levels of Bok mRNA were also expressed in granulosa cells of preovulatory follicles. Treatment of PMSGprimed mice with hCG stimulated strongly ovarian Bok mRNA expression at $6{\sim}9$ h. At that time, Bok mRNA was expressed in granulosa cells of atretic and small growing follicles. Conclusion: These results demonstrate that Bok is one of proapoptotic Bcl-2 members expressed in early growing and atretic follicles during the ovarian follicular development. Gonadotropins induce a transient increase of Bok gene expression in granulosa cells of preantral and preovulatory follicles indicating some role in the ovulatory process.

• Journal of Food Hygiene and Safety
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• v.25 no.3
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• pp.226-231
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• 2010

We aimed at the monitoring medroxyprogesterone acetate (MPA) residue amount in meats and confirmed the safety of its residue in meats. Optimized condition for analytical and instrumental methods was obtained by method validation. The limit of detection (LOD) and limit of quantification (LOQ) were validated at 1.5 and 5.0 ug/kg, respectively. The calibration curve showed good linearity ($r^2$ = 0.9968) within the concentration range of 5.0~50.0 ug/kg. We selected progesterone-d9 for internal standard, The recoveries in fortified meat ranged from 67.5 to 109.56% at the 3 spiking levels. As the regulation of MPA analysis method used by LC-MS/MS on other products have established. We selected 3 species of farm stock products (cattle, pig, chicken) and purchased at the markets of seven major cities. The total 196 of meat including 46 of domestic beef, 43 of import beef, 60 of domestic pork, 12 of import pork and 35 of domestic chicken. No residue of synthetic growth hormones were detected in cattle, pig and chicken samples tested.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.36 no.3
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• pp.233-240
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• 2010

Derivatives of a novel natural compunds, melanostatin (PLG-$NH_2$) were prepared by solid phase synthesis[1,2] and assayed to evaluate their melanogensis inhibitory activity. Also, a small library (natural compound-XLG-$NH_2$, natural compound-X LG-OH) was prepared with same method for increasing synthetic yield and cost-reduction. PLG-$NH_2$ (Proline-Leucine-Glycine-$NH_2$) was well-known tripeptide as its $\alpha$-MSH release-inhibiting activity and tyrosinase inhibitory activity[3-5]. In order to choose best candidate for peptide derivatization, various natural compounds were screened by their tyrosinase inhibitory activity. As a result, caffeic acid and coumaric acid were selected. Most of these derivatives showed better activities than the parent natural compound, melanostatin.

• Journal of Embryo Transfer
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• v.12 no.3
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• pp.293-300
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• 1997

Supplementation of maturation medium with additional granulosa cells has beneficial effect on in vitro maturation of bovine follicular oocytes and their subsequent cleavage and development in vitro. However, maturation system using granulosa cells have some disadvantages that collection of granulosa cells is cumbersome and metabolic activity of the cells is variable according to ovarian cycle or follicular size. We hypothesized that bovine immsture oocytes matured without granulosa cell coculture can fertilize and develop normally if the medium volume per oocyte is reduced during in vitro maturation. Immature oocytes were matured for 24 hours in a TCM199 containing 10% fetal calf serum, anterior pitultary hormone (0.02 AU /ml Antrinⓡ) and estradiol with or without granulosa cells in vitro. In Group 1, 35 to 40 oocytes were matured in a well of 4-well plastic dish containing 500 $\mu$l of maturation medium and granulosa cells, and 9 to 10 oocytes were matured in a 50-$\mu$l drop of maturation medium without granulosa cells in Group 2. After maturation, oocytes were coincubated with sperm for 30 hours in a modified Tyrode's medium (IVF). Inseminated oocytes were cultured in a microdrop (30 $\mu$l) of a synthetic oviduct fluld medium (SOFM) containing BSA, Minimum Essential Medium essential and non-essential amino acids for 9 days. As a preliminary experiment, we investigated the beneficial effect of granulosa cells during maturation on subsequent cleavage and development using the same type of culturedishes (4-well dish). Granulosa cells could not increase embryo cleavage after fertilization but significantly improved (p<0.05) embryo development to expanding blastocyst (Table1 and 2). In Group 1, 68 and 80% of inseminated oocytes have cleaved at 30 hours and 2 days after IVF, respectively, which is similar (p>0.05) to the result of Group 2 (69% at 30 hours and 78% at 2 days after IVF). The oocytes in Group 2 showed 21 and 11% of developmental rates to expanding and hatching blastocysts, respectively, which was not significantly different (p>0.05) from those (20 and 10%, respectively) of oocytes in Group 1. In conclusion, it has been clarified that a microdrop culture system without granulosa cells for in vitro maturation can support bovine embryonic development to blastocyst in vitro as readily as a granulosa cell coculture system.

• Journal of Life Science
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• v.33 no.5
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• pp.445-454
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• 2023

Hair graying is the result of a malfunction in the signaling pathways that control melanogenesis, and it is activated by UV light, melanocyte-stimulating hormone (MSH), stem cell factor (SCF), Wnt, and endothelin-1 (ET-1). To prevent hair graying, synthetic and natural compounds can be used to stimulate melanogenesis effectively under the control of tyrosinase, tyrosine hydroxylase, tyrosinase-related protein-1 (TRP-1), TRP-2, and microphthalmia-associated transcription factor (MITF). This article describes a crucial strategy to resolve the problem of hair graying, as well as recent advances in the signaling pathway related to melanogenesis and hair graying. In particular, the article reviews potentially effective therapeutic agents that promote melanogenesis, such as antioxidants that modulate catalase, methionine sulfoxide reductase, and sirtuin 1 (SIRT1) activators including resveratrol, fisetin, quercetin, and ginsenoside. It also discusses vitiligo inhibitors, such as corticosteroids, calcineurin inhibitors, and palmitic acid methyl ester, as well as activators of telomerase expression and activity, including estrogen, androgen, progesterone, and dihydrotestosterone. Furthermore, it explores compounds that can inhibit hair graying, such as latanoprost, erlotinib, imatinib, tamoxifen, and levodopa. In conclusion, this article focuses on recent research trends on compounds that promote melanin production related to hair graying.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.721-728
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• 2008

Hepcidin is a peptide hormone produced by the liver, of which secretion is closely related to iron status in the body. However, little is known about the molecular mechanism(s) by which this peptide regulates body iron homeostasis. The purpose of this study was to determine the effects of hepcidin treatment within the physiological concentration range on the expressions of two different iron transporter proteins-ferroportin (FPN) and divalent metal transporter 1 (DMT1). Differentiated Caco-2 intestinal cells and macrophage J774 cells were treated with either synthetic hepcidin or hepcidin-rich fraction separated from human urine at the concentration of 10 nM and 100 nM for 24 hours. Results show that hepcidin treatment in differentiated Caco-2 cells or in J774 cells did not change the level of either FPN mRNA or DMT1 mRNA. On the other hand, hepcidin treatment at the dose of 100 nM significantly decreased the FPN protein levels and DMT1 protein levels in differentiated Caco-2 cells. Similarly, urinary hepcidin treatment (10 nM & 100 nM) also significantly decreased the levels of FPN and DMT1 proteins in J774 macrophage cells. These results showed that hepcidin might play an important role in the regulation of iron homeostasis by lowering the protein levels of iron transporter FPN and DMT1 both in enterocytes and in macrophage cells.

• Proceedings of the KSAR Conference
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• 2005.06a
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• pp.47-54
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• 2005

In boars, unlike the cases in males of other species, gonadal hormones suppress voluntary feed intake. for this reason, barrows, compared with gilts or boars, eat too much feed resulting in excessive fat deposition. Two experiments were performed in the present study to investigate the effects of implantation of Revalor H[Experiment(Exp.) I: 140mg trenbolone acetate(a synthetic androgen) + 14mg estradiol-$17\beta(E_{2}\beta)$] and Compudose(Exp. II; 24mg $E_{2}\beta$) on growth efficiency, carcass characteristics and circulating concentrations of IGF-I and IGF-binding protein-3(IGFBP-3). In Exp. I, sixty-four cross-bred finishing barrows weighing approximately 60kg were randomly divided into eight pens under a 2[control vs Revalor implant] $\times$ 2(ad libitum vs $80\%$ ad libitum feeding) $\times$2[control($103\%$ NRC-recommended level) vs low-energy($87\%$ NRC recommendation) diet] arrangement of treatments. In Exp. II, effects of Compudose were studied using 80 finishing barrows(10 animals/pen). In both Exps., all the animals were slaughtered at 100- to 110-kg body weight. Both Revalor and Compudose implants caused a decrease in feed intake and backfat thickness without affecting major physicochemical characteristics of the carcass and an increase in circulating IGF-I concentration. Moreover, Revalor implant exhibited greater effects than restricted feeding, low-energy diet, or Compudose in these variables. In addition, Revalor implantation suppressed weight gain, but enhanced the feed efficiency without exhibiting any interaction with the diet or feeding. In summary, results suggest that 1) both androgen and estrogen suppress voluntary feed intake and backfat deposition and enhance IGF-I secretion and 2) these effects of the gonadal steroid hormones in growth are likely to be mediated, in part, by IGF-I in finishing barrows.

• Journal of Life Science
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• v.28 no.5
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• pp.517-523
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• 2018

Elevated levels of cortisol caused by chronic stress may lead to neuron damage in the hippocampus by activating the glucocorticoid receptors (GRs). In cortisol-deficient animals, corticosterone is known to function as a stress hormone. In humans however, corticosterone is considered a precursor of aldosterone and a glucocorticoid with similar properties to cortisol. Recently, many studies have been conducted on the role of cortisol and other synthetic glucocorticoids like dexamethasone in humans, but the exact function of corticosterone is unknown. This study examined the viability of human neuroblastoma SH-SY5Y cells treated with various concentrations of corticosterone for 24 and 48 hr via MTT assay. The MTT-assay results showed that corticosterone had an antiproliferation effect on SH-SY5Y cells at higher concentrations (500 and $1,000{\mu}M$), while in lower concentrations ($100{\mu}M$), it showed no antiproliferation effect. Cytotoxicity analysis of extracts from three medicinal crops (Liriope muscari, Schisandra chinensis, and Wolfiporia extensa) revealed that they all possessed deleterious effects on SH-SY5Y cells depending on dosage. However, it was observed that, at a concentration of $500{\mu}g/ml$, Liriope muscari attenuated the corticosterone-induced antiproliferation on SY-SH5Y cells and restored cell growth after 48 hours of treatment. The study examined the synergistic effect of six mixtures each containing $500{\mu}g/ml$ of Liriope and various concentrations of Schisandra (50 or $100{\mu}g/ml$) and Wolfiporia (10, 30, and $50{\mu}g/ml$). The results showed minor growth-restoration activity but less than that of Liriope muscari only, suggesting that Schisandra and Wolfiporia had no additive or synergistic effects.