• 한국수산과학회지
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• 제42권6호
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• pp.585-590
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• 2009

The purpose of this study was to examine the effects of oral-administered sex hormone for hybrid sturgeon, bester juvenile. The bester juveniles (2 months after hatching) were received a diet containing various doses of $17\alpha$-methyltestosterone (MT) or estradiol-$17\beta$ ($E_2$) for 6 months. Somatic growth of bester sturgeon juvenile did not show significant differences between experimental and control groups (27.9-30.5 cm; 125.1-161.7 g), although survival percentages showed a decreasing tendency in MT-treated animals. By histological examination, germ cells were recorded as smooth type in MT-treated fish and uneven type of germinal epithelium in $E_2$-treated animals. Their sex ratios were 5:4:1 (male: female: undifferentiation) in control and low dose of MT-treated fish (1 mg/kg), and 9:1:0 in fish treated with high dose of MT (10 mg/kg), whereas the ratios were reversed by both low and high doses of $E_2$ treatment, recorded as 2:8:0. Gonadal areas were not significantly differed in all trials (424,600.4 - 1,039,656.3 ${\mu}m^2$). Total number of germ cells, number of germ cells per gonadal areas and number of germ cells per area were significantly higher to 144.7-148.7 cells/section, 374.0-408.5 $cells/mm^2$ and 1,599.5-1,670.9 $cells/mm^2$ in $E_2$ treatment than those of others (30.4-63.9 cells/section, 148.4-226.9 $cells/mm^2$ and 850.0-1,050.6 $cells/mm^2$), respectively. And somatic growth according to their gender was not significantly differed between male and female.

• 한국발생생물학회지:발생과생식
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• 제23권1호
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• pp.35-42
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• 2019

Fish shows great difference in growth rate between individuals during larval development and early growth. This difference seriously reduces the production efficiency in fish culture. Growth hormone (GH)/Insulin-like growth factor 1 (IGF1) system is said to play some pivotal roles in fish growth. In this study, we investigated differences of GH, IGF1 and GHR gene expressions in juvenile red spotted grouper (Epinephelus akaara) with different growth performance. Red spotted groupers were reared under the same environmental condition (water temperature $24{\pm}1^{\circ}C$, natural light) for 96 days after hatching. They were divided into 3 groups by size (fast growing, middle growing and slow growing groups: FGG, MGG, and SGG, respectively). RNA was extracted from the brain, liver and muscle tissues from each group, and target gene expression was examined by real-time PCR. In the brain with pituitary gland, expression of GH gene in FGG was significantly higher than the expression in SGG, but the expression of IGF1 and GHR genes in the muscle was highest in SGG. Difference of GHR and IGF1 mRNA in the liver between groups with different growth performance was less clear than that in other tissues, although level of IGF1 mRNA was higher in SGG than in MGG. These results suggest that hormonal governing of growth is not the same in fast growing and slow growing fish, and size grading could cause a shift of hormonal state and growth pattern in this species.

• 한국수산과학회지
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• 제39권4호
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• pp.326-332
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• 2006

To investigate the effects of environmental salinity on the expression of the genes for growth hormone (GH) and prolactin (PRL) in the pituitary, and their receptors (GHR, PRLR) In the kidney, intestine, and gills in teleosts, we acclimated juvenile olive flounders (Paralichthys olivaceus) to different salinities (5, 15, 25, or 32 psu) for 3 days and examined their mRNA levels using the reverse transcription-polymerase chain reaction (RT-PCR). In the fish adapted to low salinity, the PRL mRNA levels in the pituitary were elevated dramatically, whereas the GH mRNA levels did not differ significantly. PRLR mRNA increased significantly in fish exposed to low salinity, whereas GHR mRNA levels did not differ. These results suggest that PRL is an important hormone for flounders that are acclimated to brackish water and it may control ion homeostasis with PRLR in the osmoregulatory organs.

• 수산해양교육연구
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• 제29권2호
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• pp.409-414
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• 2017

Effects of human chorionic gonadotropin (HCG) on ovulation and spawning of the grass puffer, Takifugu niphobles, were investigated. Matured females spawned successfully by all doses of HCG. Spawning usually occurred 24 hours after hormone injection. Body weight of adult, gonadsomatic index (GSI), pseudo-GSI, body weight of spawned egg, success rate of spawn, fertilization rate, hatching rate, and survival rate of juvenile were correlated with increasing HCG doses. However, abnormal rate of juvenile was not correlated with increasing HCG doses. These results should be useful for developing aquaculture program of grass puffer.

• 한국응용곤충학회지
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• 제43권2호
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• pp.143-153
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• 2004

경북 북부지역의 양잠농가에 피해를 주고 있는 누에(Bombyxmnri)의 미화용 유발 문제에 대한 원인과 기작을 밝혀내는 데, 이 연구의 궁극적 목적을 두었다. 일반 사육환경에서 나타날 수 있는 발육온도(20, 25, 3$0^{\circ}C$)와 최종령 초기 유충 체중 변이(412.6-1,616.0 mg)는 누에의 용화 결정에 영향을 주지 많았다 한편 유약호르몬(juvenile hormone：計I)동력제인 피리프록시팬(pyriproxyfen)은 10-s M의 낮은 농도에서도 난포세포 개방화를 유도하여, 이 약제가 누에에서도 동력제라는 것을 확인하였다. 피리프록시펜은 약제 농도 및 처리 시기별로 특이하게 누에 미화용 유발 효과를 보였다. 피리프록시펜은 JH 에스테라제(JH esterase： JHE)를 직접적으로 억제하지 못하고, 오히려 활성을 증가시키는 것으로 나타났으며, JH 결합단백질(JH binding protein：JHBP)의 유전자 발현을 억제하는 것으로 나타났다. 즉, 피리프록시펜은 체내에 JH 동력제로 작용하면서 JHE 유전자 활성을 제고시켰지만, JHE활성 증가에 따른 체내 JH함량이 줄어듬에 따라 JHBP의 유전자 활성을 억제하는 것으로 해석된다. 양잠농가 주변으로 살포 가능성이 있는 농약을 대상으로 난포세포 개방화 분석을 실시 한 결과, 제초제 3종(simazine, molinate, alachlor)이 JH 동력제 효과를 가지고 있는 것으로 나타났다. 누에 미화용 원인체 규명을 위해서 이들에 대한 직접 노출 시험이 요구된다.

• 한국잠사곤충학회지
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• 제37권2호
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• pp.114-120
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• 1995

현재 누에 장려품종의 원종 및 교잡종을 대상으로 JH제(마니나)를 투여한 후, 발육경과일수, 화용비율, 전견중, 견층중 등의 차이를 조사하여 품종간의 JH 감수성을 비교하였다. JH제 처리에 의한 유충경과일수의 연장은 원종간에 다양한 차이를 나타내, 잠114가 2일 이상 지연된데 비하여 잠121, 잠123, 잠138에서는 거의 변화가 없었다. 유충기간의 연장과 함께 대부분의 원종에서 전견중과 견층중이 증가하였으나, 잠114의 경우에는 5령기간의 연장에도 불구하고 오히려 감소하였다. 교잡종의 경우, 모든 품종이 JH제 처리에 의해 유충기간이 1일 정도 연장됨으로서 원종에서와 같은 품종간의 차이는 나타나지 않았다. 유충섭식기간의 연장에 따라 대부분의 품종에서 전견중과 견층중이 증가하였으며 특히 사성잠, 은백잠, 삼광잠에서 JH의 효과가 뚜렷하였다. JH제의 처리에 의한 특별한 생리적장애는 보이지 않았지만, 잠122, 잠131, 잠135 및 잠138 등의 원종에서는 JH제 처리에 의해 화용비율이 10% 이상 떨어짐으로서 이들 품종에서 JH의 생리적 감수성이 인정되었다.

• BMB Reports
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• 제44권6호
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• pp.393-398
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• 2011

Polydnaviruses are a group of double-stranded DNA viruses and are symbiotically associated with some ichneumonoid wasps. As proviruses, the replication of polydnaviruses occurs in the female reproductive organ at the pupal stage. This study analyzed the effects of two developmental hormones, juvenile hormone (JH) and ecdysteroid, on the viral replication of Cotesia plutellae bracovirus (CpBV). All 23 CpBV segments identified contained a conserved excision/rejoining site ('AGCTTT') from their proviral segments. Using quantitative real-time PCR based on this excision/rejoining site marker, initiation of CpBV replication was determined to have occurred on day 4 on the pupal stage. Pyriproxyfen, a JH agonist, significantly inhibited adult emergence of C. plutellae, whereas RH5992, an ecdysteroid agonist, had no inhibitory effect. Although RH5992 had no effect dose on adult development, it significantly accelerated viral replication. The results of immunoblotting assays against viral coat proteins support the effects of the hormone agonists on viral replication.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 추계학술대회 논문집
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• pp.291-292
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• 2010

• 약학회지
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• 제28권1호
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• pp.1-10
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• 1984

A total synthesis of dehydrojuvabione which has high juvenile hormone activity, is described. The kinetic enloate of mesityl oxide is used as nucleophilic synthon for this synthesis. 1,4-Dioxaspiro [4,5] decan-8-carboxaldehyde was treated with kinetic enolate of mesityl oxide to give 8-(1'-hydroxy-5'-methyl-3'-oxo-4'-hexenyl)-1,4-dioxaspiro [4,5] decane. The latter compound was dehydrated. The resulted dienone was treated with lithium dimethylcuprate. After that, appropriate transformation was performed to give dehydrojuvabione.

• Journal of Forest and Environmental Science
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• 제30권2호
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• pp.218-225
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• 2014

Studies were carried out to standardize and develop a suitable macro-propagation technology for large scale production of superior clonal stock through stem cuttings in Commiphora wightii Arnott (Bhandari), a data deficient medicinal plant of arid region. For the purpose, three experiments were conducted. The first experiment was tried to elucidate the impact of various cutting diameters (0.50-0.75 cm, 0.75-1.00 cm, 1.00-1.50 cm, and >1.50 cm) in combination with varying growing conditions (sunlight, shade house and mist chamber) on shoot sprouting and rooting without using exogenous plant growth regulators. Cutting diameter (size 0.75-1.00 cm) in mist chamber has shown maximum sprouting (90.00%) and rooting (73.33%), primary root (6.67) and secondary root (16.67) followed by 1.00-1.51 cm in mist chamber. Minimum sprouting (40.00%), rooting (33.33%), number of shoot (1.33), primary root (1.00) and number of secondary root (1.00) was recorded in cutting diameter (size >1.50 cm) in sunlight. Second experiment was performed to find out optimum growth regulator concentration of rooting hormone (100, 200, 500 and 1000 ppm) of Indole-3-acetic acid (IAA) and Indole-3-butyric Acid (IBA) on adventitious root formation on cuttings diameter (size 0.25-0.50 cm) in comparison to control. Maximum rooting percentage (93.33%) was recorded in 200 ppm followed by 500 ppm (86.66%) of IBA as compared to control, which showed only 60 per cent sprouting. Third experiment was performed with newly formed juvenile micro-cuttings treated with varying concentrations of IAA and IBA. The juvenile cuttings (size 6-10 cm, basal dia <0.25 cm) were selected as micro-cuttings. The cuttings treated with IBA (500 ppm) showed 64.30% rooting as compared to other treatments. Results of above experiments indicate that cuttings (size 0.75-1.00 cm dia) may be developed in mist chamber for better performance. While using heavier cuttings, no growth promoting hormones is required however; growth regulator 200 ppm concentration of IBA rooting hormone was observed optimum for promoting macro-propagation in stem cuttings of lower diameter class (0.25-0.50 cm).