• 한국염색가공학회지
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• 제4권2호
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• pp.64-68
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• 1992

The charge-transfer(CT) complexes derived from phenothiazine as donor and quinonoid compounds as accepters were evaluated as coloring matter. Light fastness of the intermolecular charge-transfer(CT) complex dyes as well as absorption wavelength is an important factor when the complexes are applied to coloring matters. The photofading mechanism of CT complex dyes of phenothiazine and accepters were examined. The addition of effective radical scavenger, antioxidant and photostabilizer gave a remarkable enhancement of the photostability of CT dyes.

• 폴리머
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• 제25권5호
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• pp.719-727
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• 2001

유기광도전체에 있어서의 액정은 종래의 분자 배향성을 가지지 않는 비정성 고체계와는 달리 분자 배향성을 가지기 때문에 분자 사이의 질서도가 높아지게 되고, charge-carrier의 hopping을 방해하는 hopping site의 공간적인 틈이 작아져 고 이동도의 특성을 가질수 있다. 본 연구에서는 유기광도전체의 전하 수송층에 액정5CT를 혼합하여, charge-carrier수송특성에 있어서의 액정5CT의 영향을 관찰하였다. 액정5CT를 함유한 유기광도전체는 액정의 혼합비가 증가함에 따가 초기전위는 증가하였으며, 암감쇄는 감소하는 경향을 나타내었다. 감도는 5CT를 TNF와 OXD 각자에 대하여 40 wt%로 혼합한 시료의 경우에 가장 우수하게 나타났다. 형광거동을 관찰한 결과, 이는 전하수송재료와 액정5CT의 전하 수송착체에 의한 것으로, 액정5CT를 TNF와 OXD 각각에 대하여 40 wt%로 혼합한 시료의 경우가 다른 시료에 비해 전하 수송착체가 가장 잘 형성되어, 성공을 잘 수송하기 때문으로 나타났다.

• 한국방사선학회논문지
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• 제13권7호
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• pp.941-946
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• 2019

환자의 진단 및 치료를 결정할 때 전산화단층촬영 (computed tomography; CT)은 우수한 해부학 정보를 제공하기 때문에 진단에 큰 도움이 되어 있다. 그에 따른 사용빈도가 증가하고 있으며, 활용 및 응용범위도 확대되어가는 추세이다. 저관전압을 사용해서 CT 검사를 하면 노이즈가 증가한다. 기존의 여러 연구에서는 영상재구성법에 대한 노출조건을 조절하는 방법 등을 시도해서 최적의 화질을 찾는 방법을 찾고 있으나 근본적 문제해결은 되지 못한다. 입력 영상의 신호를 유지하고 노이즈만을 최대한 제거하기 위해서 이중 트리웨이블릿 알고리즘을 적용하였다. 실험결과 100kVp, 회전시간 0.5sec의 영상에서 complex oriented 2d 방을 사용 할 경우 노이즈는 8.53에서 4.51로 줄어들었다. 본 연구를 통해서 저관전압 두부 CT에서 발생하는 높은 수준의 노이즈를 최적의 노이즈제거 알고리즘으로 노이즈를 제거하고 환자선 량을 낮출 수 있었다. 본 연구결과를 임상에서 사용 시 저선량의 CT 사용이 가능하고 환자 피폭을 줄일 것으로 판단한다.

• Molecules and Cells
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• 제43권6호
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• pp.517-529
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• 2020

Carboxyl-terminal binding proteins (CtBPs) are transcription regulators that control gene expression in multiple cellular processes. Our recent findings indicated that overexpression of CtBP2 caused the repression of multiple bone development and differentiation genes, resulting in atrophic nonunion. Therefore, disrupting the CtBP2-associated transcriptional complex with small molecules may be an effective strategy to prevent nonunion. In the present study, we developed an in vitro screening system in yeast cells to identify small molecules capable of disrupting the CtBP2-p300 interaction. Herein, we focus our studies on revealing the in vitro and in vivo effects of a small molecule NSM00158, which showed the strongest inhibition of the CtBP2-p300 interaction in vitro. Our results indicated that NSM00158 could specifically disrupt CtBP2 function and cause the disassociation of the CtBP2-p300-Runx2 complex. The impairment of this complex led to failed binding of Runx2 to its downstream targets, causing their upregulation. Using a mouse fracture model, we evaluated the in vivo effect of NSM00158 on preventing nonunion. Consistent with the in vitro results, the NSM00158 treatment resulted in the upregulation of Runx2 downstream targets. Importantly, we found that the administration of NSM00158 could prevent the occurrence of nonunion. Our results suggest that NSM00158 represents a new potential compound to prevent the occurrence of nonunion by disrupting CtBP2 function and impairing the assembly of the CtBP2-p300-Runx2 transcriptional complex.

• BMB Reports
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• 제50권4호
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• pp.186-193
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• 2017

In mammals, cap-dependent translation of mRNAs is initiated by two distinct mechanisms: cap-binding complex (CBC; a heterodimer of CBP80 and 20)-dependent translation (CT) and eIF4E-dependent translation (ET). Both translation initiation mechanisms share common features in driving cap- dependent translation; nevertheless, they can be distinguished from each other based on their molecular features and biological roles. CT is largely associated with mRNA surveillance such as nonsense-mediated mRNA decay (NMD), whereas ET is predominantly involved in the bulk of protein synthesis. However, several recent studies have demonstrated that CT and ET have similar roles in protein synthesis and mRNA surveillance. In a subset of mRNAs, CT preferentially drives the cap-dependent translation, as ET does, and ET is responsible for mRNA surveillance, as CT does. In this review, we summarize and compare the molecular features of CT and ET with a focus on the emerging roles of CT in translation.

• 한국염색가공학회지
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• 제4권1호
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• pp.21-25
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• 1992

The charge-transfer(CT) complexes derived from various donors and acceptors were evaluated as coloring matter. Dyes absorbing light in the region from the visible to the near-infrared wavelengths were synthesized. In order to determine the molar ratio of the donor to the acceptor in the CT complex in the solution, the continuous variational method was applied to each system. A 1:1 correspondence between the donor and the acceptor molecules in the CT complex in the solution is established. Color development properties in paper were examined. The longer the exposure time at constant temperature, the deeper the strength of color in paper. The strength of color at high temperature was decreased, because sublimed CT dyes in paper were migrated out side of paper.

• Bulletin of the Korean Chemical Society
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• 제19권12호
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• pp.1337-1341
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• 1998

The charge transfer (CT) complex dyes between electron donor phenothiazine and electron acceptors namely, 2, 3-dichloro-1,4-naphtoquinone and 2,3-dichloro-5-nitro-1,4-naphtoquinone, were formed in the dichloromethane solution and electrochromic properties were studied using Bu4NC1O4 as supporting electrolyte. A 1 : 1 correspondence between the donor and acceptor molecules in the CT complex was found.

• Bulletin of the Korean Chemical Society
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• 제34권12호
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• pp.3695-3702
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• 2013

A nickel(II) complex $[Ni(H_2biim)_2(H_2O)_2](ClO_4)_2{\cdot}H_2O$ (1) of biimidazole ligand has been synthesized and characterized (Where $H_2biim$ = 2,2'-biimidazole). The single crystal X-ray diffraction of the complex shows a dimeric structure with six coordinated psudo-octahedral geometry. The cyclic voltammograms of complex exhibited one quasireversible reduction wave ($E_{pc}=-0.61V$) and an irreversible oxidation wave ($E_{pa}=1.28V$) in DMF solution. The interaction of the complex with Calf-Thymus DNA (CT-DNA) has been investigated by absorption and fluorescence spectroscopy. The complex is an avid DNA binder with a binding constant value of $1.03{\times}10^5M^{-1}$. The results suggest that the nickel(II) complex bind to CT-DNA via intercalative mode and can quench the fluorescence intensity of EB bind to CT-DNA with $K_{app}$ value of $3.2{\times}10^5M^{-1}$. The complex also shown efficient oxidative cleavage of supercoiled pBR322 DNA in the presence of hydrogen peroxide as oxidizing agent. The DNA cleavage by complex in presence of quenchers; viz. DMSO, KI, $NaN_3$ and EDTA reveals that hydroxyl radical or singlet oxygen mechanism is involved. The complex showed invitro antimicrobial activity against four bacteria and two fungi. The antimicrobial activity was nearer to that of standard drugs and greater than that of the free ligand.

• The Korean Journal of Pain
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• 제30권3호
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• pp.165-175
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• 2017

Nuclear medicine imaging is widely used in pain medicine. Low back pain is commonly encountered by physicians, with its prevalence from 49% to 70%. Computed tomography (CT) or magnetic resonance imaging (MRI) are usually used to evaluate the cause of low back pain, however, these findings from these scans could also be observed in asymptomatic patients. Bone scintigraphy has an additional value in patients with low back pain. Complex regional pain syndrome (CRPS) is defined as a painful disorder of the extremities, which is characterized by sensory, autonomic, vasomotor, and trophic disturbances. To assist the diagnosis of CRPS, three-phase bone scintigraphy is thought to be superior compared to other modalities, and could be used to rule out CRPS due to its high specificity. Studies regarding the effect of bone scintigraphy in patients with extremity pain have not been widely conducted. Ultrasound, CT and MRI are widely used imaging modalities for evaluating extremity pain. However, SPECT/CT has an additional role in assessing pain in the extremities.

• Korean Journal of Radiology
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• 제22권3호
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• pp.308-323
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• 2021

An increasing number of adult congenital heart disease (ACHD) patients continue to require life-long diagnostic imaging surveillance using cardiac CT and MRI. These patients typically exhibit a large spectrum of unique anatomical and functional changes resulting from either single- or multi-stage palliation and surgical correction. Radiologists involved in the diagnostic task of monitoring treatment effects and detecting potential complications should be familiar with common cardiac CT and MRI findings observed in patients with repaired complex ACHD. This review article highlights the contemporary role of CT and MRI in three commonly encountered repaired ACHD: repaired tetralogy of Fallot, transposition of the great arteries after arterial switch operation, and functional single ventricle after Fontan operation.