• Textile Coloration and Finishing
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• v.4 no.2
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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.

• Polymer(Korea)
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• v.25 no.5
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• pp.719-727
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• 2001

Recently it was found that the charge carrier transport properties are significantly enhanced due to effective intermolecular $\pi$-orbital overlapping and low disorder of hopping sites caused by self-organization of liquid crystal molecules. In this study, the xerographic properties of a double-layer photoconductor doped with nematic liquid crystal, 4-pentyl-4'-cyanoterphenyl (5CT), as a charge-carrier transport material to enhance the charge-tarrier mobility were investigated. From the results of measured surface voltage properties for the photoconductor doped with various concentrations of liquid crystal, 5CT, the initial voltage was found to increase with the concentration of 5CT and the dark decay decreased with the concentration of 5CT. The highest sensitivity was obtained at a specific concentration, 40wt% 5CT. The fluorescence behavior of the carrier transport layer (CTL) was also investigated. It was found that the charge-carrier transport properties of the organic photoconductor depend on the charge-carrier transport properties of the complex. The TNF : 5CT (40 wt%) and OXD : 5CT (40 wt%)samples showed the highest sensitivity because the greatest charge transport complex was termed between the charge-carrier transport materials in these samples.

• Journal of the Korean Society of Radiology
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• v.13 no.7
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• pp.941-946
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• 2019

Computed tomography (CT) has been increasing in frequency and indications for use in clinical diagnosis and treatment decisions. Multidetector CT has the advantage of shortening the inspection time and obtaining a high resolution image compared to a single detector CT, but has been pointed out the disadvantage of increasing the radiation exposure. In addition, when the low tube voltage is used to reduce the exposure dose in the CT, noise increases relatively. In the existing method, the method of finding the optimal image quality using the method of adjusting the parameters of the image reconstruction method is not a fundamental measure. In this study, we applied a double-tree complex wavelet algorithm and analyzed the results to maintain the normal signal and remove only noise. Experimental results show that the noise is reduced from 8.53 to 4.51 when using a complex oriented 2D method with 100kVp and 0.5sec rotation time. Through this study, it was possible to remove the noise and reduce the patient dose by using the optimal noise reduction algorithm. The results of this study can be used to reduce the exposure of patients due to the low dose of CT.

• Molecules and Cells
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• v.43 no.6
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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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• v.50 no.4
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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.

• Textile Coloration and Finishing
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• v.4 no.1
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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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• v.19 no.12
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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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• v.34 no.12
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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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• v.30 no.3
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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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• v.22 no.3
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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.