• BMB Reports
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• v.29 no.6
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• pp.525-529
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• 1996

Ligand binding properties of muscarinic acetylcholine receptors (mAChRs) in the nematode Caenorhabditis elegans (C. elegans) were characterized by using filtration binding assays. Scatchard analysis using $[^{3}H]N-methylscopolamine$ ($[^{3}H]NMS$) showed that the dissociation constant ($K_d$) and the maximum binding value ($B_{max}$) were $3.3{\pm}0.8{\times}10^{10}$ M and $9.0{\pm}1.1$ fmol/mg protein, respectively. Binding competition experiments indicated that the affinities of C. elegans mAChRs to atropine, scopolamine, and oxotremorine were similar to those of mammalian mAChRs. Pirenzepine binding experiments revealed that the binding pattern of mAChRs in C. elegans closely resembled that of mAChRs in rat brain, suggesting that the receptors consist primarily of Ml subtype. The affinity of mAChRs for oxotrernorine was significantly affected by guanylylimidodiphosphate (Gpp(NH)p), a non hydrolyzable GTP analog, suggesting that mAChRs in C. elegans might be coupled to G proteins. The data presented here indicate the possibility that C. elegans provides a living animal model to study the action mode of the muscarinic cholinergic system.

• Journal of Life Science
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• v.28 no.12
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• pp.1432-1437
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• 2018

Clara cell secretory protein (CCSP) plays an important role in protecting the lungs from inflammation. This research focuses on identifying the cis-element for binding the repressor of CCSP gene expression. A DNase I footprinting experiment revealed three protected regions between -812 and -768 bp (45 bp) of the mCCSP promoter. One motif (D3: GCCTGGGAA) was 100% conserved across rat, hamster, and human. The addition of excess amounts of the D3 motif exhibited high competition within that 45 bp range in an electrophoretic mobility shift assay. However, when mutated D3 ($G{\underline{AA}}TG{\underline{TT}}AA$) was used, the competition was significantly reduced. This demonstrates that the D3 motif within that 45 bp region of the mCCSP promoter is an important site for the protein-DNA interaction. Transient transfection assays with -756 Luc resulted in highly decreased expression of CCSP than those with -812 Luc, suggesting that the 45 bp could function as a binding site for the repressor. Co-transfection of KLF4 exhibited significant repression of the -812 Luc but not the -768 Luc which clearly shows that KLF4 might function as a repressor for the CCSP gene and also suggests that the D3 motif is strongly involved in the binding of KLF4. In addition, when anti-KLF4 antibody was added, super-shifted bands were observed. This result demonstrates that KLF4 could function as a repressor by binding to this 45 bp region of the CCSP promoter and that the D3 motif might be involved in the specific binding of KLF4.

• Journal of Korea Fair Competition Federation
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• no.125
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• pp.86-91
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• 2006

지난 2006. 3. 2 한 대기업이 영창악기(주) 인수를 위한 우선 협상대상자로 선정되었다. 공정거래위원회가 삼익악기와 영창악기의 기업결합을 불허하는 결정을 하고, 영창악기가 부도처리 되어 법정관리에 들어간 지 대략 1년여 정도의 시간이 흐른 후에 일어난 일이다. 뒤돌아보면 이 기업결합의 경우 언론, 학계, 업계 등에서 큰 관심을 보였고, 공정위의 최종결정에 대해 각계에서 격려와 함께 많은 비판이 있었던 사례였다. 그리고 아직도 사법적 판단이 계속 진행되고 있는 사례이기도 하다. 조만간 영창악기의 운명이 확정되고, 그동안 활발했던 논의는 기억에서도 사라질 것이다. 하지만 이 사례는 많은 사람들로 하여금 기업결합 심사제도에 대해 관심을 갖고 생각하는 계기를 제공했었다. 따라서 지난 기업결합 심사의 주요내용과 쟁점사항 등을 살펴보면서 그동안의 논의를 간략히 정리하는 기회를 갖기로 한다.

• Journal of Korea Fair Competition Federation
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• no.25
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• pp.73-75
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• 1997

공정거래위원회는 산업연구원(KIET)과 공동으로 지난 9월 3일(수) 대한상공회의소에서 300여명의 학계, 업계 및 관계부처 공무원들이 참석한 가운데$\lceil$카르텔 국제규범화의 영향 및 대응$\rfloor$이라는 주제로 $\lceil$제2회 국제경쟁정책 세미나$\rfloor$를 개최하였다. 동 세미나는 내년 4월에 확정될 카르텔관련 OECD 정책권고에서 각국의 경성카르텔(가격 고정, 생산량 제한, 시장분할 등) 금지원칙의 확립과, 적용제외 카르텔의 축소 및 제거 등을 통해 효과적인 경쟁법 집행체제를 확립하고, 회원국 양자 또는 다자협정을 통해 비밀정보를 공유하는 등 카르텔에서의 국제 협력의 강화, 특히 경성카르텔에 대한 국제적 공조조사 등의 법집행을 강화한다는 내용이 담길 것으로 예상됨에 따라, 경쟁정책 국제규범화(소위 경쟁라운드:CR)에 대한 정부와 기업의 적절한 대응방안 모색을 위한 방향을 제시하는 데 있다. 동 세미나에는 경쟁정책 분야의 세계적인 권위자인 하버드대 프레드릭 쉬어러(F.M. Scherer) 교수의 기조연설에 이어 테리 윈슬로(Terry Winslow) OECD 사무국 자문관과 KDI의 신광식 연구위원 등 4명의 국내외 전문가들의 주제발표와 지정 및 자유토론이 이루어졌다.

• Archives of Pharmacal Research
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• v.21 no.4
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• pp.452-457
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• 1998

Three compounds, 5-(acetoxymethyl)-5-(hydroxymethyl)-3-tetradecyl-2,5-dihydro-2-furanone (3), 5-(acetoxymethyl)-5-(hydroxymethyl)-3,3-dihexyltetrahydro-2-furanone (4) and 5-(acetoxymethyl)-5-(hydroxymethyl)-3,3-dioctyltetrahydro-2-furanone (5), were designed and synthesized as surrogates of the ultrapotent DAG analogue, 5-(acetoxymethyl)-5-(hydroxymethyl) 3-[(Z)-tetradecylideneltetrahydro-2-furanone (1), a compound that showed high affinity for PKC-$\alpha$ ($K_1$=35 nM) in a competition binding assay with [$^3H$-20]phorbol-12,13-dibutyrate (PDBU). In an attempt to overcome the problem of generating geometrical E- and Z- isomers, as encountered with 1, the double bond was moved to an endocyclic location as in 3, or an additional alkyl chain was appended to C3 to give the corresponding 3,3-dialkyl saturated lactones (4 and 5). The lactone was constructed from glycidyl-4-methoxyphenyl ether in 5 steps. The target compounds showed reduced binding affinities for PKC-.alpha. with $K_{i}$ values of 192 nM (3), 4,829 nM (4), and 2,812 nM (5), respectively. These results indicate that constrained DAG analogues having a tetrahydro-2-furanone template are effectively discriminated by PKC-(X in terms of the direction of the long alkyl chain connected to the 3-position.n.

• Korean Journal of Pharmacognosy
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• v.32 no.3 s.126
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• pp.219-225
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• 2001

The water extracts of 82 Korean medicinal herbs were examined for the binding affinity on the recombinant human muscarinic acetylcholine receptor subtype 1 $(mAChR-M_1)$ produced from the CHO (Chinese Hamster Ovary) cell line. Of those tested, the extracts of Coptidis Rhizoma, Phellodendri Cortex, Hedyotis Herba and of Terminariae Fructus were found to exhibit a significant competition with $[^3H]$ N-methyl-scopolamine for the specific binding to $mAChR-M_1$ in a dose dependent manner, respectively.

• Journal of fish pathology
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• v.14 no.1
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• pp.31-36
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• 2001

A novel clonidine binding sites were characterized in the intestinal membrane isolated from seawater eels, Anguilla japonica. The specific clonidine binding sites consisted of at least two classes, high affinity ($K_d=1.4{\pm}0.3$ nM n = 5) and low affinity ($K_d=175{\pm}34$ nM n = 5) sites. The specific binding of 2 nM [$^3H$]clonidine was most enhanced at $20^{\circ}C$ and pH 7.5, and reversed by unlabelled clonidine. Such binding was hardly inhibited by adrenaline, yohimbine or rauwolscine, indicating that most binding sites are distinct from $\alpha_2$-adrenoceptor. The specific clonidine binding sites was inhibited by various imidazoline/guanidinium drugs, indicating existence of imidazoline/guanidinium receptive sites (IGRS) or imidazoline receptors in the eel intestine. Competition experiments revealed that rank order to displace 2 nM [$^3H$]clonidine from their binding sites was as follows : guanabenz > cirazoline = naphazoline = UK14,304 = ST587 $\geq$ clonidine $\geq$ idazoxan = RX821002 = tolazoline > ST93 = oxymetazoline = amiloride = ST91 > yohimbine = efaroxan = rauwolscine $\geq$ adrenaline = ST567 = histamine = agmatine. Although physiological role of IGRS is not clear yet even in mammalian cell/tissues, eel intestine may be a good model to elucidate how the IGRS act in the cell and to decide what is the endogenous ligand for the IGRS.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.4
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• pp.17-27
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• 1980

All types of weed community became dominant by Monochoria vaginalis (Burm.) Presl. as the nitrogen level increased. The importance value (IV.) of M vaginalis rapidly increased with increasing nitrogen level whereas the LV. of other weed species decreased. At the 10 $\times$ 10cm plant spacing, M. vaginalis was almost totally suppressed at all nitrogen levels. At the 20 $\times$ 20cm plant spacing, the degree of suppression declined with increasing nitrogen level. At the 30 $\times$ 30cm plant spacing, there was no suppression of M vaginalis at the highest nitrogen level. The yield obtained at the 10 $\times$ 10cm plant spacing when M. vaginalis was present was not significantly different from that obtained from the weed free plot for all rice cultivars while it was significantly reduced by M vaginalis competition at the 20 $\times$ 20cm and 30 $\times$ 30cm plant spacings. The difference in yield caused by M vaginalis competition was primarily due to a reduction in the number of panicles at all nitrogen levels. There was a high negative correlation between grain yield and weed weight at heading. The yield reduction due to weed competition varied depending upon the nitrogen level.

• Journal of Digital Convergence
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• v.15 no.2
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• pp.465-473
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• 2017

The purpose of this study was to verify the validity of the developed evaluation method for competition intelligence of sport talented children of of Kim et al.(2015). For this purpose, total 3 times of observation by sports leaders were accomplished for evaluation of competition intelligence. After finishing final observation, the correlation between the sub-factors(practice intelligence, learning intelligence, and training intelligence) and gifted students' physical fitness and KOSTASS were examined. First, as the reliability, the correlations between leaders' observation results were significantly higher than 0.8 in all sub-factors. Second, all sub-factors of competition intelligence showed significant positive correlation with in standing jump, 50m dash and side step test improvement(p<.05). Third, all sub-factors showed no significant correlation with KOSTASS(p>.05). These results showed that the evaluation tool by Kim et al.(2015) didn't not fully reflect the improvement level of basic physical fitness factors of the gifted students. However, the results of correlation between physical fitness factors requiring technical learning process showed that the gymnastic gauging tools included learning process and task acquisition level.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.spc1
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• pp.236-241
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• 2006

We measured the secondary production of the amphipod Monocorophium acherusicum Costa in a seagrass bed (Zostera marina L.) in Gwangyang Bay, southern Korea. M. acherusicum biomass was positively correlated (P<0.05) with seagrass standing crop, suggesting that there were biological interactions between the two species. M. acherusicum displays two main breeding periods per year: spring (March to April) and fall (October to November). M. acherusicum biomass in the spring breeding periods was higher than in the fall. Annual secondary production of M. acherusicum was 3.54 g DW/$m^2$/yr with an annual P/B ratio of 3.48. Secondary production and the P/B ratio of M. acherusicum were lower than those observed for other amphipods inhabiting seagrass beds. These results suggest that biological interactions between M. acherusicum and seagrass, as well as dietary competition with other amphipods can potentially cause declines in secondary production and the P/B ratio.