• Nuclear Engineering and Technology
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• 제54권9호
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• pp.3235-3241
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• 2022

The Korea Atomic Energy Research Institute (KAERI) is planning the construction of the KIJANG Research Reactor (KJRR) for stable supply of ⁹⁹Mo. The Fission ⁹⁹Mo Production Process (FMPP) of KJRR produces solid waste such as spent uranium cake and alumina cake, and liquid waste in the form of intermediate level liquid waste (ILLW) and low level liquid waste (LLLW). This study thus established the operating range and optimum operating conditions for the cementation of ILLW from FMPP. It also evaluated whether cement waste form samples produced under optimum operational conditions satisfy the waste acceptance criteria (WAC) of a disposal facility in Korea (Korea radioactive waste agency, KORAD). Considering economic feasibility and safety, optimum operational conditions were achieved at a w/c ratio of 0.55, and the corresponding salt content was 5.71 wt%. The cement waste form samples prepared under optimum operational conditions were found to satisfy KORAD's WAC when tested for structural stability and leachability. The results indicate that the proposed cementation conditions for the disposal of ILLW from FMMP can be effectively applied to KJRR's disposal facility.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2018년도 춘계학술논문요약집
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• pp.208-209
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• 2018

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.83-83
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• 2003

The lutropin/choriogonadotropin receptor (LHR) is a member of the rhodopsin-like subfamily of G protein coupled receptor (GPCRs), that has been shown to mediate the internalization of its two naturally occurring agonist, lutropin and choriogonadotropin (CG). The clustered agonist-receptor complex is internalized by a dynamin-dependent pathway and traverses the endosomal compartment without agonist dissociation Dissociation of the agonist-receptor complex occurs in the lysosomes, where both the agonist and receptor are degrade. Recently, constitutively activating mutations of the receptor have been identified that are associated with familial male-precocious puberty (FMPP). A FMPP is a form of sexual precocious puberty in boys in which testosterone levels are elevated independent of changes in luteinizing hormone-releasing hormone and serum luteinizing hormone levels, We have now analyzed two naturally occurring, constitutively active mutants of the human LHR. These mutations were introduced into the rat LHR (rLHR) and are designated L435R and D556Y. Cells expressing rLHR-D556Y bind human choriogonadotropin (hCG) with normal affinity, exhibit a 25-fold increase in basal cAMP and respond to hCG with a normal increase in cAMP accumulation. Cells expressing rLHR-L435R also bind hCG with normal affinity, exhibit a 47-fold increase in basal cAMP, and do not respond to hCG with a further increase in cAMP accumulation. This mutation enhances the internalization of the free and agonist-occupied receptors ~2- and ~17- fold, respectively We conclude that the state of activation of the rLHR can modulate its basal and/or agonist-stimulated internalization. Since the internalization of hCG is involved in the termination of hCG actions, we suggest that the lack of responsiveness detected in cells expressing rLHR-L435R is due to the fast rate of internalization of the bound hCG. The finding that membranes expressing rLHR-L435R respond to hCG with an increase in adenylyl cyclase activity supports this suggestion. Autonomous Leydig cell activity in FMPP is caused by a constitutively activating LH/CGR.

• 한국가축번식학회지
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• 제24권1호
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• pp.41-47
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• 2000

성선자극호르몬 수용체 (LH/CGR)는 7번 막을 통과하는 수용체의 일종이다. LH/CGR의 유전자 돌연변이 질환은 남성에 있어서 이들 수용체가 조기에 발현되어 조기 성숙의 원인이 된다. 이러한 수용체의 기능을 분석하기 위하여 556번째의 아미노산 (D)을 Y로 치환한 돌연변이 수용체 (D556Y)를 만들었다. 이러한 돌연변이 수용체를 동물세포에 발현시켜 cAMP의 분석결과 Ligand (호르몬)가 없어도 지속적으로 정보전달을 세포내부로 보내 cAMP 발현을 현저히 증가시켰다. 따라서 남성의 조기성숙과 관련된 질환은 지속적으로 발현하는 LH /CGR에 의한 원인 때문일 것이다.