• 한국잠사곤충학회지
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• 제35권1호
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• pp.28-35
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• 1993

누에 5령 유충에 유약호르몬 유연화합물(JHA)인 "마니나"를 투여하여 JHA처리 후의 누에 성장 및 성충화발육에 미치는 영향에 관하여 조사하였다. JHA는 5령 유충의 섭식기간의 연장과 이에 따른 체중의 증가를 가져왔으며 성충화 발육 기간도 1~1.5일 연장시켰다. 혈액, 피부, 소화관, 지방체, 난소 등에 관한 형태 및 단백질 성분변화를 조사한 결과 이들 조직, 기관들 역시 JHA에 의해 성충화 발육이 1-2일 정도씩 지체되고 있음이 밝혀졌다. JHA의 성충화 발육의 지연에 대한 내분비학적 고찰과 잠종생산 증대를 위한 JHA의 이용 가능성에 대하여 검토하였다.대하여 검토하였다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1996년도 한국생물과학협회 국제학술대회
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• pp.161.1-161
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• 1996

No Abstract, See Full Text

• 한국식물학회:학술대회논문집
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• 한국식물학회 1987년도 식물생명공학 심포지움 논문집 Proceedings of Symposia on Plant Biotechnology
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• pp.191-211
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• 1987

Common usage of the concept of juvenility implies that there is one physiological phase, the juvenile phase, which manifests itself in the various morphological and physiological phenomena observed in juvenile higher plants. The juvenile phase is often defined as that time from seed germination until the plant attains the ability to flower regulating such behaviour. This definition precludes plants from flowering in the juvenile phase. It is of major interest, therefore, to identify the physiological controls(Bluehreife) regulating such behavior. The length of the juvenile period in higher plants ranges from one year to over 60 years in different species. The long juvenile period of seedling is the main cause of the long duration of the breeding process. I determined the length of the juvenile period in various plants and its control of phase changes in natural system in relation to factors such as plant size and age, shoot morphology, apex size, root system and phytohormonal and nutritional status is reviewed. From the own experimental and observational evidence available it appears that both hormonal and nutritional factors can be involved in control of juvenility but that a specific juvenile or flowering hormone is not involved. Grafting, ringing, scoring, root pruning and fertilization have been used to accelerate flowering, but in most cases these cultured treatments are only successful on plants that were passed the juvenile phase. It is suggested that there are intrinsic difference between the meristematic cells of the apieces of juvenile and adult shoot, which are thus determined with respect to there development potentialities. The problems associated with the maintenance of the determined state through mitosis are discussed. The properties of transitional forms of Ribes nigrum L. intermediate between the juvenile and adult phase, are descrived and there implications discussed. Analogies are drawn between juvenile phenomena in woody perennials and in herbaceous species.

• 한국잠사곤충학회지
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• 제39권2호
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• pp.161-168
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• 1997

To clarify the effect of anti-juvenile hormone analogue (AJH) on the larval ecdysis by feeding at early stage of the 4th instar, the total amount of protein and activity of chitinolytic enzymes in the integument of Bombyx mori were analyzed, PAGE pattern of the protein was observed and the morphological changes of integument during molting period were also observed and the morphological changes of integument during molting period were also observed by means of TEM. The total amount of protein was greatly increased in premolting, then reached maximum level just before ecdysis, and rapidly decreased after the larval ecdysis in the control, while in the AJH treatment, increased 12 hr later than the control and its maximum was only 82.6% of the control. Two specific proteins, which were presumed as the protein originated from endocuticle, also appeared 12 hr later than the control and were maintained to 132 hr after AJH treatment from the aspects of the Native- and SDS-PAGE patterns, although those of the control disappeared instantly after ecdysis. Chitinase and $\beta$-N-acetylglucosaminidase activities were also suppressed and delayed by AJH treatment. Furthermore, it was observed that the apolysis took place 12 hr later than the control but new epicuticle was not formed at least until 132 hr after AJH treatment. From these results, it is suggested that the larval molting process of silkworm develops 12 hr later than the control but new epicuticle was not formed at least until 132 hr after AJH treatment. From these results, it is suggested that the larval molting process of silkworm develops 12 hr later than the control by AJH treatment but no further processing takes place just after apolysis.

• 한국응용곤충학회지
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• 제35권3호
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• pp.238-242
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• 1996

몇가지 협력제의 7-ethoxy precocene II와 협력작용을 통한 활성증가와 작용기작을 구명하기 위하여 mikweed bug, Oncopeltus fasciatus 2령충에 항유약호르몬유사물과 협력제가 처리된 petri dish에 접종하여 생리활성 정도를 측정하였다. 얻어진 결과는 다음과 같다. 7-Ehtoxy precocene II의 반수활성농도는 $1.18\mu$g/$\textrm{cm}^2$이었다. 7-Ethoxy precocene II와 다른 산화저해제인 RO20-9747의 협력비가 14.05로 가장 높았고 그들의 반수활성농도는 $0.084\mu$$g/\textrm{cm}^2$이었다. 7-Ethoxy precocene II와 다른 협력제 1종, 2종, 4종을 조합을 달리하여 처리하였을 때 뚜렷한 협력작용 증가효과를 가져오지 못했다. 이상의 결과에서 다른 협력제들은 곤충의 방어기작을 알라타체를 포함하여 비선택적으로 저해하는 것으로 생각되었으나 RO20-9747은 7-ethoxy precocene II가 알라타체로 이행하는데 까지 곤충의 방어적 산화기작인 monooxygenase 활성을 선택적으로 저해함으로써 7-ethoxy precocene II가 알라타체로 이행량이 증가하여 활성증가를 가져온 것으로 생각되었다.

• 한국잠사곤충학회지
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• 제28권1호
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• pp.37-42
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• 1986

누에의 5령 60시간째 합성효약 홀몬(JHA)을 체중 1g당 1$\mu\textrm{g}$, 10$\mu\textrm{g}$을 경피투여한 후 체액 중 단백질 및 아미노산의 변동을 조사하였던 바 그 결과는 다음과 같다. 1. 5령유충기간은 대조구보다 JHA-1구가 1일, JHA-10구가 4일 연장되었다. 2. 견종 및 견층종은 합성효약 홀몬 투여구가 대조구보다 무거웠고, 견층비율은 JHA-10구가 낮았다. 3. 체액단백질의 농도는 합성효약홀몬투여구가 대조구에 비해 현저하게 증가하였다. 4. 체액 중 전 아미노산양은 JHA-10구가 대조구에 비해 약 2배 정도 많았으며, 특히 glycine와 arginine의 증가 정도는 현저하다.

• Biomolecules & Therapeutics
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• 제26권5호
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• pp.512-519
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• 2018

Phthalates widely used in the manufacture of plastics have deeply penetrated into our everyday lives. Recently, a concern over the toxicity of phthalates on thyroid, has been raised but in most of cases, the doses employed were unrealistically high. To investigate the effects of phthalates on thyroid, we investigated the effects of the repeated oral exposure to low to high doses (0.3, 3, 30 and 150 mg/kg) di-2-ethylhexylphthalate (DEHP) from weaning to maturity for 90 days in juvenile rats on the thyroid. The histological examination revealed that DEHP significantly induced hyperplasia in the thyroid from the doses of 30 mg/kg, which was confirmed with Ki67 staining. In line with this finding, increased mRNA expression of thyrotropin releasing hormone (Trh) was observed in the thyroid of female at 0.3 mg/kg and 150 mg/kg as determined by RNAseq analysis. Moreover, significantly increased expression of parathyroid hormone (Pth) in the female at 0.3 mg/kg, and thyroglobulin (Tg) and thyroid hormone responsive (Thrsp) in the male at 0.3 mg/kg were noted in the blood, of which changes were substantially attenuated at 150 m/kg, alluding the meaningful effects of low dose DEHP on the thyroid hormone regulation. Urinary excretion of mono-2-ethylhexyl-phthalate (MEHP), a major metabolite of DEHP was determined to be 4.10 and 12.26 ppb in male, 6.65 and 324 ppb in female at 0.3 and 30 mg/kg DEHP, respectively, which fell within reported human urine levels. Collectively, these results suggest a potential adverse effects of low dose phthalates on the thyroid.

• 한국잠사학회:학술대회논문집
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• 한국잠사학회 2000년도 잠사과학 100주년 국제심포지엄 및 추계학술대회
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• pp.37-37
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• 2000

• 한국응용곤충학회지
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• 제34권1호
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• pp.20-32
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• 1995

Adult diapause in insects is characterized by suppression of reproductive development. It is induced by environmental cues such as photoperiod, temperature, food availability, and other conditions Diapause-inducing environment is recognized and analyzed by the brain of the insects. The interpreted information is conveyed via endocrine system to target tissues such as ovaries, fat body, and other tissues. From this signal hierarchy of a brain-endocrine-target tissue axis, several factors are involved to express a diapause trait in a quantitative mode, even though the insects show a binomial phenotye between being in diapause or not. Recent works estimated that the number of the factors is relatively small by a series of crossing trials between high and low diapause lines. Heritability of the diapause is quite high (ca. 70%) in some species. Epistasis, sex-linkage, pleiotropism, and other nongenetic components also affect diapause inheritance. Most physiological studies have been focused on control mechanisms of the juvenile hormone (JH) synthesis in corpora allata (CA) because JH level in hemolymph of teneral adults is critical to decide a later developmental mode. Allatostatin, an antagonizer of JH synthesis, has been believed to be a potent brain message to CA for adult diapause induction.

• 한국응용곤충학회지
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• 제61권1호
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• pp.109-115
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• 2022

난황형성과정(Vitellogenesis)은 발달하는 난모세포에 난황이 축적되는 과정으로, 이 과정의 개시는 알형성과정(oogenesis)을 제어하는 주요 메커니즘이다. 곤충생리학 모델인 노랑초파리(Drosophila melanogaster)에서 난황형성과정은 성충으로 우화한 직후 시작하여 성적 성숙이 일어나는 2-3일간 지속된다. 성숙한 난모세포가 충분히 만들어지고 성적 성숙이 종료되면, 짝짓기 후 알형성과정이 다시 시작될 때까지 난황형성과정은 멈춘다. 수컷 초파리의 정액 단백질인 성 펩타이드(Sex peptide, SP)는 짝짓기의 신호로서 알라타체(corpora allata)를 자극해 유약호르몬(Juvenile hormone, JH) 생합성 및 분비를 유도하며, 혈림프(hemolymph) JH 농도의 증가는 난황형성과정을 자극한다. 최근 연구 결과에 따르면, SP수용체 뉴런은 자궁 내막의 수상돌기를 통해 교미 중 정액과 함께 자궁으로 전달된 SP를 감지함으로써, 축삭돌기를 통해 중추신경계인 복부 신경절에 짝짓기 신호를 보내는데, 이러한 중추신경계 SP 신호가 JH 생합성 및 분비, 그리고 난황형성과정을 유도하는 것으로 밝혀졌다. 짝짓기 후 암컷에서의 난황형성과정은 일주기 리듬을 보이는데, 노랑초파리의 일주기 리듬은 중추 신경계 뉴런들에 의해 제어된다. 본 종설은 성적 성숙, 짝짓기 신호, 그리고 일주기 리듬에 따라 난황형성과정을 제어하는 신경 메커니즘에 관한 최근 연구 성과를 다룬다.