• Title/Summary/Keyword: Contrast Agent

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An Intertextual Approach to Narcissa Benbow in Sanctuary, Sartoris and "There Was a Queen" (나시서 벤보우에 관한 상호텍스트적 연구)

  • Shin, Young-Hun;Kang, Ji-Hyun
    • The Journal of the Korea Contents Association
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    • v.20 no.2
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    • pp.300-309
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    • 2020
  • Recent studies on William Faulkner's female characters have overcome much of the stereotyped and dichotomous approaches of the past by uncovering their subversive characteristics. Nevertheless, they still present some limitations in regards to analyzing the characters based on individual texts. This paper attempts an inter-textual approach to Narcissa Benbow, the central character of Sanctuary, Sartoris and "There Was a Queen." In Sanctuary, Narcissa, a young widow of a Southern aristocratic family, harshly accuses her brother Horace, a lawyer of taking a murder suspect's wife and her infant child to their old house. She is afraid that their existence could harm the reputation of her family and herself. Eventually, she kicks them out of the house. In contrast, she is described as being friendly and calm in Sartoris. In addition, in "There Was a Queen," Narcissa makes an attempt to get an obscene letter back from an FBI agent in exchange for a sexual favor in order to prevent the letter from being disclosed. This paper takes into account the possibility of seeing these incoherent or even contradictory aspects of her characterization with a consistent view. This confirms that an inter-textual approach is needed to properly understand those round female characters created by Faulkner.

Combined MRI and Relaxogram: A New Method of Fat Study (MRI와 Relaxogram을 이용한 지질 연구의 새로운 기법에 관한 연구)

  • Yongmin Chang;Yoo, Done-Sik;Kim, Tae-Hun;Kim, Yong-Joo;Kang, Duk-Sik;Robert B. Clarkson
    • Progress in Medical Physics
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    • v.10 no.1
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    • pp.23-32
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    • 1999
  • Combined MRI and Relaxogram approach was introduced as a very useful tool for fat study. The phantoms simulating homogeneous mixture of fat and non-fat environments were measured with spin echo pulse sequence on a 0.15 T whole body imager. From 45 scans, the Tl values were obtained by fitting the data to continuous distribution (CONTIN) of relaxation time. This relaxogram gives broad distributions of relaxation time, which are characterized by a number of peaks with characteristic T1 values. Two distinct peaks in relaxogram were observed and identified as signals from com oil and gelatin gel. This model system can be served as simulating the distribution of fat in muscle. Also the relative ratio of two components, which is proportional to the area under the peak, is estimated and compared to nominal values. Based on the good agreement between two predictions, the values from our proposed method agreed with nominal values within $\pm$7 % error. The effects of different concentration of contrast agent and different region of interest are presented. To optimize total scan times, the minimum required data points and so further reduction in total scan times are discussed.

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Evaluation of Interlayer Shear Properties and Bonding Strengths of a Stress-Absorbing Membrane Interlayer and Development of a Predictive Model for Fracture Energy (덧씌우기 응력흡수층에 대한 전단, 부착강도 평가 및 파괴에너지 예측모델 개발)

  • Kim, Dowan;Mun, Sungho;Kwon, Ohsun;Moon, Kihoon
    • International Journal of Highway Engineering
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    • v.20 no.1
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    • pp.87-95
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    • 2018
  • PURPOSES : A geo-grid pavement, e.g., a stress-absorbing membrane interlayer (SAMI), can be applied to an asphalt-overlay method on the existing surface-pavement layer for pavement maintenance related to reflection cracking. Reflection cracking can occur when a crack in the existing surface layer influences the overlay pavement. It can reduce the pavement life cycle and adversely affect traffic safety. Moreover, a failed overlay can reduce the economic value. In this regard, the objective of this study is to evaluate the bonding properties between the rigid pavement and a SAMI by using the direct shear test and the pull-off test. The predicted fractural energy functions with the shear stress were determined from a numerical analysis of the moving average method and the polynomial regression method. METHODS : In this research, the shear and pull-off tests were performed to evaluate the properties of mixtures constructed using no interlayer, a tack-coat, and SAMI with fabric and without fabric. The lower mixture parts (describing the existing pavement) were mixed using the 25-40-8 joint cement-concrete standard. The overlay layer was constructed especially using polymer-modified stone mastic asphalt (SMA) pavement. It was composed of an SMA aggregate gradation and applied as the modified agent. The sixth polynomial regression equation and the general moving average method were utilized to estimate the interlayer shear strength. These numerical analysis methods were also used to determine the predictive models for estimating the fracture energy. RESULTS : From the direct shear test and the pull-off test results, the mixture bonded using the tack-coat (applied as the interlayer between the overlay layer and the jointed cement concrete) had the strongest shear resistance and bonding strength. In contrast, the SAMI pavement without fiber has a strong need for fractural energy at failure. CONCLUSIONS : The effects of site-reflection cracking can be determined using the same tests on cored specimens. Further, an empirical-mechanical finite-element method (FEM) must be done to understand the appropriate SAMI application. In this regard, the FEM application analy pavement-design analysis using thesis and bonding property tests using cored specimens from public roads will be conducted in further research.

TAp73 and ΔNp73 Have Opposing Roles in 5-aza-2'-Deoxycytidine-Induced Apoptosis in Breast Cancer Cells

  • Lai, Jing;Yang, Fang;Zhang, Wenwen;Wang, Yanru;Xu, Jing;Song, Wei;Huang, Guichun;Gu, Jun;Guan, Xiaoxiang
    • Molecules and Cells
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    • v.37 no.8
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    • pp.605-612
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    • 2014
  • The p73 gene contains an extrinsic P1 promoter and an intrinsic P2 promoter, controlling the transcription of the pro-apoptotic TAp73 isoform and the anti-apoptotic ${\Delta}Np73$ isoform, respectively. The DNA methylation status of both promoters act equally in the epigenetic transcriptional regulation of their relevant isoforms. The aim of this study was to analyze the different effects of these p73 isoforms in 5-aza-2'-deoxycytidine (5-aza-dC)-induced apoptosis in breast cancer cells. We investigated the effects of the DNA demethylation agent, 5-aza-dC, on the T-47D breast cancer cell line, and evaluated the methylation status of the p73 promoters and expression of TAp73 and ${\Delta}Np73$. Furthermore, we assessed the expression of p53 and p73 isoforms in 5-aza-dC-treated T-47D cells and p53 knockout cells. 5-aza-dC induced significant anti-tumor effects in T-47D cells, including inhibition of cell viability, G1 phase arrest and apoptosis. This was associated with p73 promoter demethylation and a concomitant increase in TAp73 mRNA and protein expression. In contrast, the methylation status of promoter P2 was not associated with ${\Delta}Np73$ mRNA or protein levels. Furthermore, demethylation of P2 failed to inhibit the expression of ${\Delta}Np73$ with 5-aza-dC in the p53 knockdown cell model. Our study suggests that demethylation of the P1 and P2 promoters has opposite effects on the expression of p73 isoforms, namely up-regulation of TAp73 and down-regulation of ${\Delta}Np73$. We also demonstrate that p53 likely contributes to 5-aza-dC-induced ${\Delta}Np73$ transcriptional inactivation in breast cancer cells.

Comparison of Hounsfield Units by Changing in Size of Physical Area and Setting Size o f Region o f Interest b y Using the CT Phantom Made with a 3D Printer (3D 프린터로 제작된 CT 팬톰을 이용한 물리적 관심영역과 설정 관심영역의 크기에 따른 하운스필드의 비교)

  • Seoung, Youl-Hun
    • Journal of radiological science and technology
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    • v.38 no.4
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    • pp.421-427
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    • 2015
  • In this study, we have observed the change of the Hounsfield (HU) in the alteration of by changing in size of physical area and setting size of region of interest (ROI) at focus on kVp and mAs. Four-channel multi-detector computed tomography was used to get transverse axial scanning images and HU. Three dimensional printer which is type of fused deposition modeling (FDM) was used to produce the Phantom. The structure of the phantom was designed to be a type of cylinder that contains 33 mm, 24 mm, 19 mm, 16 mm, 9 mm size of circle holes that are symmetrically located. It was charged with mixing iodine contrast agent and distilled water in the holes. The images were gained with changing by 90 kVp, 120 kVp, 140 kVp and 50 mAs, 100 mAs, 150 mAs, respectively. The 'image J' was used to get the HU measurement of gained images of ROI. As a result, it was confirmed that kVp affects to HU more than mAs. And it is suggested that the smaller size of physical area, the more decreasing HU even in material of a uniform density and the smaller setting size of ROI, the more increasing HU. Therefore, it is reason that to set maximum ROI within 5 HU is the best way to minimize in the alteration of by changing in size of physical area and setting size of region of interest.

[I-123]IPT SPECT Dopamine Reuptake Site Imaging: Differences in Normal Controls and Parkinson's Patients by Semiquantitative Analysis Methods ([I-123]IPT SPECT를 이용한 도파민 재섭취부위의 영상화: 반정성적 분석방법을 이용한 정상인과 파킨슨병 환자의 차이)

  • Kim, Hee-Joung;Im, Joo-Hyuck;Yang, Seoung-Oh;Ryu, Jin-Sook;Choi, Yun-Young;Lee, Myung-Chong;Lee, Hee-Kyung
    • The Korean Journal of Nuclear Medicine
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    • v.30 no.1
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    • pp.35-46
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    • 1996
  • Dopamine transporter concentrations have been known to decrease in Parkinson's disease (PD) or increase in Tourette's disorder. The purpose of this study was to evaluate the effectiveness of [I-123]N-(3-iodopropene-2-yl)-$2{\beta}$-carbomethoxy-$3{\beta}$-(4-chlorophenyl) tropane (IPT) as an imaging agent for measuring changes in transporter concentrations with PD. IPT labelled with 6.69+/-0.64 mCi(247.53+/-23.68 MBq) of I-123 was intravenously injected into ten patients(age: 55+/-11) with PD, and six normal controls(NC)(age: 46+/-14) as a bolus. Dynamic SPECT scans of the brain were then performed for 5 minutes each over 120 minutes on a triple headed camera. Time activity curves were generated for the left basal ganglia(LBG), right basal ganglia(RBC), and occipital cortex(OCC). The statistical parameters included the time to peak activity, the contrast ratio of LBG and RBG to OCC at several time points, and the accumulated specific binding counts/mCi/pixel(ASBC) from 0 to 115 minutes. The uptake of IPT in the brains of PD and NC peaked within 10 minutes of injection in all subjects. The maximum target to background ratio in the basal ganglia of PD and NC occurred at 85+/-20 min and 110+/-6 min of injection, respectively. The BG/OCC ratios at 115 minutes for PD and NC were 2.15+/-0.54 and 4.26+/-0.73, respectively. The ASBC at 115 minutes for PD and NC were 152.91+/-50.09 and 289.51+/-49.00, respectively. The ratio of BG/OCC for the NC was significantly higher than the ratio for PD. SPECT data matched with clinical diagnosis for PDs. The ratio between BG and OCC and the ASBC for PD were clearly separated from NC and may be useful outcome measures for clinical diagnosis. The findings suggest that IPT may be a very useful tracer for early diagnosis of PD and study of dopamine reuptake site.

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Development of Hepatitis C Virus (HCV) Genome-Targeting Hammerhead Ribozyme Which Activity Can Be Allosterically Regulated by HCV NS5B RNA Replicase (C형 간염바이러스(HCV)의 NS5B RNA Replicase에 의해 그 활성이 조절되는 HCV지놈 표적 Hammerhead 리보자임 개발)

  • Lee, Chang-Ho;Lee, Seong-Wook
    • Korean Journal of Microbiology
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    • v.43 no.3
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    • pp.159-165
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    • 2007
  • For the development of basic genetic materials for specific and effective therapeutic approach to suppress multiplication of hepatitis C virus (HCV), HCV internal ribosome entry site (IRES)-targeting hammerhead ribozyme which activity is allosterically regulated by HCV regulatory protein, NS5B RNA replicase, was developed. The ribozyme targeted most effectively to +382 nucleotide (nt) site of HCV IRES RNA. The allosteric ribozyme was designed to be composed of sequence of RNA aptamer to HCV NS5B, communication module sequence which can transfer structural transition for inducing ribozyme activity upon binding NS5B to the aptamer, and sequence of ribozyme targeting +382 nt of HCV IRES. Noticeably, we employed in vitro selection technology to identify the most appropriate communication module sequence which can induce ribozyme activity depending on the US5B protein. We demonstrated that the ribozyme was nonfunctional either in the absence of any proteins or in the presence of control bovine serum albumin. In sharp contrast, the allosteric ribozyme can induce activity of cleavage reaction with HCV IRES RNA in the presence of the HCV NS5B protein. This allosteric ribozyme can be used as lead compound for specific and effective anti-HCV agent, tool for highthroughput screening to isolate lead chemicals for HCV therapeutics, and ligand for biosensor system for HCV diagnosis.

Pathological Effect of Melatonin on Vascular Endothelial Cell Detachment (혈관내피세포 탈착에 미치는 melatonin의 병리학적 영향)

  • Seo, Jeong-Hwa;Kim, Sung-Hyen;Ahn, Sun-Young;Jeong, Eun-Sil;Cho, Jin-Gu;Park, Heon-Yong
    • Journal of Life Science
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    • v.20 no.6
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    • pp.914-921
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    • 2010
  • In this study, we carried out a series of experiments to know whether melatonin, an anti-oxidative and immunosuppressive agent, played an important role in endothelial cells. It was revealed that melatonin had little or no effect on endothelial proliferation, cell death or migration. Additionally, melatonin had no effect on adhesion of THP-1 leukocytes to bovine aortic endothelial cells (BAECs) and THP-1 homotypic cell aggregation. In contrast, it was shown that melatonin diminished the basal level of nitric oxide by PP2A-mediated dephosphorylation of endothelial nitric oxide synthase (eNOS), leading to enhanced detachment of BAEC from the extracellular matrix. Collectively, melatonin in high doses decreases the NO production via regulations of PP2A and eNOS activities, inducing detachment of endothelial cells, a possible initial step for thrombosis.

The most appropriate antimitotic treatment of Ara-C in Schwann cell-enriched culture from dorsal root ganglia of new born rat

  • Kim, Soung-Min;Jahng, Jeong-Won;Lee, Jong-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.32 no.1
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    • pp.42-51
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    • 2006
  • Schwann cell, one of important components of peripheral nervous system, interact with neurons to mutually support the growth and replication of embryonal nerves and to maintain the different functions of adult nerves. The Ara-C, known as an antimitotic agent, have been used to have high effectiveness in eliminating fibroblasts during Schwann cell culture period. This enrichment effect is also known to be cummulative with each successive pulse of Ara-C applied and is due to a progressive loss of fibroblasts. But the cytotoxicity by Ara-C is also cummulative and noticeable over the period. To determine the most effective application time and interval of Ara-C in the Schwann cell culture, we observed the Schwann cell purity and density with the Ara-C treatment in plain and three-dimensional culture from dorsal root ganglion of new born rat. By culturing dispersed dorsal root ganglia, we can repeatedly generate homogenous Schwann cells, and cellular morphology and cell count with mean percentages were evaluated in the plain culture dishes and in the immunostainings of S-100 and GFAP in the three-dimensional culture. The Ara-C treated cultures showed a higher Schwann cell percentage (31.0%${\pm}$8.09% in P4 group to 65.5%${\pm}$24.08% in P2 group), compared with that obtained in the abscence of Ara-C (17.6%${\pm}$6.03%) in the plain culture after 2 weeks. And in the three-dimensional culture, S-100 positive cells increased to 56.22%${\pm}$0.67% and GFAP positive cells to 66.46%${\pm}$1.83% in G2 group (p<0.05), higher yield than other groups with Ara-C application. Therefore, we concluded that the Ara-C treatment is effective for the proliferation of Schwann cells contrast to the fibroblasts in vitro culture, and the first application after 24 hours from cell harvesting and subsequent 2 pulse treatment (P2 group in plain culture and G2 group in three-dimensional culture) was more effective than other application protocols.

Ultrasmall Polyethyleneimine-Gold Nanoparticles with High Stability (높은 안정성을 갖는 초미립 폴리에틸렌이민-금 나노입자)

  • Kim, Eun-Jung;Yeum, Jeong-Hyun;Ghim, Han-Do;Lee, Se-Guen;Lee, Ga-Hyun;Lee, Hyun-Ju;Han, Sang-Ik;Choi, Jin-Hyun
    • Polymer(Korea)
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    • v.35 no.2
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    • pp.161-165
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    • 2011
  • This study is related to the preparation of biocompatible gold nanoparticles (AuNPs) which are stable in aqueous solutions for a long time. Ultrasmall polyethyleneimine (PEI)-capped AuNPs (PEI-AuNPs) with limited agglomeration were prepared in aqueous solutions at room temperature, which were based on the roles of PEI as a reductant and a stabilizer. PEI-AuNPs with an average size of 8~12 nm formed highly stable nanocolloids with an average hydrodynamic cluster size of around 50 nm in aqueous media. At a low concentration of metal precursor hydrogen tetrachloroaurate (III), the particle size was reduced noticeably. The typical peaks of gold were observed in the X-ray diffraction pattern of AuNPs. The cell viability of 98% was obtained in the case of PEI-AuNPs, while PEI was cytotoxic. The PEI-AuNP is considered to be a potential candidate as a contrast agent for computed tomography.