479 results on '"Tae Wook Kang"'
Search Results
252. Quantitative Phosphoproteomics of the Human Neural Stem Cell Differentiation into Oligodendrocyte by Mass Spectrometry
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Kun Cho, Jin Young Kim, Eunmin Kim, Gun Wook Park, Tae Wook Kang, Jung Hae Yoon, Seung U. Kim, Kyunghee Byun, and Jong Shin Yoo
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LTQ-FT MS ,lcsh:QD71-142 ,Phosphoproteomics ,lcsh:Analytical chemistry ,TiO2 ,SILAC ,Oligodendrocyte ,Neural Stem Cell (NSC) - Abstract
Cellular processes such as proliferation, differentiation, and adaptation to environmental changes are regulated by protein phosphorylation. In order to enhance the understanding of molecular dynamics for biological process in detail, it is necessary to develop sensitive and comprehensive analytical methods for the determination of protein phosphorylation. Neural stem cells hold great promise for neural repair following an injury or disease. In this study, we made differentiated oligodendrocytes from human neural stem cells using over-expression of olig2 gene. We confirmed using quantitative phosphoproteome analysis approach that combines stable isotope labeling by amino acids in cell culture (SILAC) and TiO2 micro-column for phosphopeptide enrichment with MS2 and MS3 mass spectrometry. We detected 275 phosphopeptides which were modulated at least 2-fold between human neural stem cells and oligodendrocytes. Among them, 23 phosphoproteins were up-regulated in oligodendrocytes and 79 phosphoproteins were up-regulated in F3 cells.
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- 2012
253. A Study on The Correlation Analysis Between IFC and CityGML for Efficient Utilization of Construction Data and GIS Data
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Jung Rae Hwang, Chang-Hee Hong, and Tae-Wook Kang
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Engineering ,Data model (ArcGIS) ,business.industry ,Correlation analysis ,Plan (drawing) ,Data mining ,CityGML ,business ,computer.software_genre ,computer ,Data modeling - Abstract
Recently, various researches have been attempted to link or integrate BIM and GIS. In particular, some of the researches were progressed to convert the data model between the BIM standard model IFC and the GIS standard model CityGML. However, it is hard to utilize the previous research results yet because characteristics and domains of between two data models are very different, In order to obtain the correlation between BIM and GIS, in this research, we analyzed the characteristics between IFC and CityGML objects of each LOD, And, we analyzed the correlation of IFC and CityGML by performing mapping between IFC and CityGML objects from view point of building with these characteristics. In this research, based on these correlation analysis results, we proposed the efficient interrelation plan between IFC and CityGML.
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- 2012
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254. Development of Mechanistic-Empirical Overlay Pavement Design Program
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Tae-Wook Kang, Cheol-Min Baek, Hee-Mun Park, and Sunglin Yang
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Transport engineering ,Asphalt concrete ,Engineering ,Pavement engineering ,Asphalt ,business.industry ,Sensitivity (control systems) ,Overlay ,business ,Civil engineering - Abstract
PURPOSES : Recently, the mechanistic-empirical overlay pavement design program that is linked with Korea Pavement Research Program (KPRP) has been developed. This paper focused on establishing the framework and developing the program for the asphalt overlay design over the existing asphalt concrete pavement. METHODS : The overlay pavement design program developed in this study was investigated to assess the sensitivity to various pavement conditions, such as the damage level and thickness of existing layers. In addition, the actual overlay design on currently performing pavement was carried out as a practical example. RESULTS : From the sensitivity analysis, it was found that the thickness and damage level of existing asphalt layer mostly affect the overlay design results. In addition, under the same condition, the overlay pavement would better perform in cold region. From the overlay design with the actual condition, it is noted that the overlay thickness varies depending on the given condition. CONCLUSIONS : Based on various evaluations, it was concluded that the overlay design program developed in this study is a reliable and reasonable tool to be used in the actual pavement design.
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- 2012
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255. O-GlcNAc Regulates Pluripotency and Reprogramming by Directly Acting on Core Components of the Pluripotency Network
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Tae-Wook Kang, Tae Wan Kim, Yoo Wook Kwon, Soo Youn Choi, Hong Duk Youn, Sungho Yoon, Eun Jung Cho, Hyonchol Jang, and Seon-Young Kim
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Pluripotent Stem Cells ,Glycosylation ,Transcription, Genetic ,Somatic cell ,Molecular Sequence Data ,Regulator ,Biology ,Models, Biological ,Acetylglucosamine ,Mice ,SOX2 ,Genetics ,Animals ,Humans ,Gene Regulatory Networks ,Amino Acid Sequence ,Induced pluripotent stem cell ,reproductive and urinary physiology ,Embryonic Stem Cells ,Cell Proliferation ,Regulation of gene expression ,SOXB1 Transcription Factors ,Gene Expression Regulation, Developmental ,Cell Differentiation ,Cell Biology ,Cellular Reprogramming ,Embryonic stem cell ,Cell biology ,Mice, Inbred C57BL ,KLF2 ,embryonic structures ,Mutation ,Molecular Medicine ,biological phenomena, cell phenomena, and immunity ,Reprogramming ,Octamer Transcription Factor-3 - Abstract
SummaryO-linked-N-acetylglucosamine (O-GlcNAc) has emerged as a critical regulator of diverse cellular processes, but its role in embryonic stem cells (ESCs) and pluripotency has not been investigated. Here we show that O-GlcNAcylation directly regulates core components of the pluripotency network. Blocking O-GlcNAcylation disrupts ESC self-renewal and reprogramming of somatic cells to induced pluripotent stem cells. The core reprogramming factors Oct4 and Sox2 are O-GlcNAcylated in ESCs, but the O-GlcNAc modification is rapidly removed upon differentiation. O-GlcNAc modification of threonine 228 in Oct4 regulates Oct4 transcriptional activity and is important for inducing many pluripotency-related genes, including Klf2, Klf5, Nr5a2, Tbx3, and Tcl1. A T228A point mutation that eliminates this O-GlcNAc modification reduces the capacity of Oct4 to maintain ESC self-renewal and reprogram somatic cells. Overall, our study makes a direct connection between O-GlcNAcylation of key regulatory transcription factors and the activity of the pluripotency network.
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- 2012
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256. Pyruvate kinase M2 promotes the growth of gastric cancer cells via regulation of Bcl-xL expression at transcriptional level
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Kyu-Sang Song, David Pocalyko, Seon-Young Kim, Jeong-Hwan Kim, Tae-Wook Kang, Woo-Ho Kim, Zhi Xie, Oh-Hyung Kwon, Yong Sung Kim, Hyang-Sook Yoo, Seung-Moo Noh, and Mirang Kim
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Transcription, Genetic ,Pyruvate Kinase ,bcl-X Protein ,Biophysics ,PKM2 ,Biology ,Biochemistry ,Stomach Neoplasms ,Cell Line, Tumor ,Biomarkers, Tumor ,medicine ,Humans ,Glycolysis ,Molecular Biology ,Cell Proliferation ,Regulation of gene expression ,Cell growth ,Transcription Factor RelA ,Cancer ,Cell Biology ,Prognosis ,medicine.disease ,Cell biology ,Gene Expression Regulation, Neoplastic ,Anaerobic glycolysis ,Gene Knockdown Techniques ,Cancer cell ,Pyruvate kinase - Abstract
PKM2 is an isoenzyme of the glycolytic enzyme pyruvate kinase that promotes aerobic glycolysis. Here, we describe an important role for PKM2 in regulating the survival of gastric cancer (GC) cells. We showed that PKM2 was overexpressed in gastric tumor tissues compared to normal tissues and its expression level was associated with poor survival of gastric cancer patients. We also showed that PKM2 affected cell survival by regulating Bcl-xL at the transcriptional level. PKM2 knockdown partially affected the stability of NF-kB subunit p65, suggesting that post-translational regulation of p65 by PKM2 is one of plausible mechanisms for the increased cell growth. Therefore, PKM2 may function as an upstream molecule that regulates p65 function and thus enhances the growth of tumor cells.
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- 2012
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257. CaGe: A Web-Based Cancer Gene Annotation System for Cancer Genomics
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Young-Kyu Park, Tae-Wook Kang, Yong Sung Kim, Su-Jin Baek, Doheon Lee, Seon-Young Kim, and Kwon-Il Kim
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Cancer genome sequencing ,Candidate gene ,lcsh:QH426-470 ,cancer gene ,Health Informatics ,Genomics ,Biology ,medicine.disease_cause ,DNA sequencing ,Article ,03 medical and health sciences ,0302 clinical medicine ,Genetics ,medicine ,Serial analysis of gene expression ,Gene ,Ecology, Evolution, Behavior and Systematics ,030304 developmental biology ,0303 health sciences ,Mutation ,pathway ,Cancer ,medicine.disease ,high-throughput genomic technology ,lcsh:Genetics ,annotation ,030220 oncology & carcinogenesis ,next-generation sequencing ,mutation - Abstract
High-throughput genomic technologies (HGTs), including next-generation DNA sequencing (NGS), microarray, and serial analysis of gene expression (SAGE), have become effective experimental tools for cancer genomics to identify cancer-associated somatic genomic alterations and genes. The main hurdle in cancer genomics is to identify the real causative mutations or genes out of many candidates from an HGT-based cancer genomic analysis. One useful approach is to refer to known cancer genes and associated information. The list of known cancer genes can be used to determine candidates of cancer driver mutations, while cancer gene-related information, including gene expression, protein-protein interaction, and pathways, can be useful for scoring novel candidates. Some cancer gene or mutation databases exist for this purpose, but few specialized tools exist for an automated analysis of a long gene list from an HGT-based cancer genomic analysis. This report presents a new web-accessible bioinformatic tool, called CaGe, a cancer genome annotation system for the assessment of candidates of cancer genes from HGT-based cancer genomics. The tool provides users with information on cancer-related genes, mutations, pathways, and associated annotations through annotation and browsing functions. With this tool, researchers can classify their candidate genes from cancer genome studies into either previously reported or novel categories of cancer genes and gain insight into underlying carcinogenic mechanisms through a pathway analysis. We show the usefulness of CaGe by assessing its performance in annotating somatic mutations from a published small cell lung cancer study.
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- 2012
258. The Study on the Optimized Earthwork Transfer Path Algorithm Considering the Precluded Area of Massive Cutting and Banking
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Yoon Ho Cho and Tae-Wook Kang
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Engineering ,business.industry ,Transfer (computing) ,Earthworks ,Path (graph theory) ,Polygon ,Topology (electrical circuits) ,Minimum cost path ,Transfer model ,Visibility ,business ,Algorithm ,Civil engineering - Abstract
The purpose of this study is to suggest the optimized transfer algorithm of earthwork considering the precluded area such as the lake, bogs. The earthwork transfer plan in massive cutting and banking should be established because of affecting the construction cost highly. Until now, there was the study about the optimized earthwork transfer model considering the OR(Operating Research). but isn`t the study about the model considering the precluded area such as the lake, bogs. In most cases, the engineer adjusts the earthwork transfer path considering the precluded area, manually. The presented model suggests to calculate various visibility paths with algorithm after converting the precluded area to polygon topology. By using this paths, the minimum cost path to optimize the earthwork transfer can be obtained. In this study, the validity of the model was proved as implementing the system for the optimized earthwork transfer considering the precluded area.
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- 2011
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259. The Study for the Realtime Noise Simulation Integration Model Applied to Traffic Simulation and Spatial Modeling
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Yoon Ho Cho, In Tai Kim, and Tae-Wook Kang
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Moment (mathematics) ,Noise ,Engineering ,Series (mathematics) ,business.industry ,Headway ,Traffic simulation ,Point (geometry) ,Simulation integration ,business ,Field (computer science) ,Simulation - Abstract
The noise prediction model, KRON-2006, in South Korea has been developed for obtaining the average noise level. The model is based on an outdoor sound propagation method based on ISO9613 and ASJ Model-1998 and supports the analysis of the linear noise source, such as highway, for obtaining Leq. Because of that, the model can`t obtain Lmax, Lmin from the time series noise profile based on traffic at every moment. In order to address this problem, the real time noise prediction model based on traffic simulation using GIS model and algorithm is proposed. It can predict the vehicle point noise level based on vehicle type, speed generated from traffic simulation by using headway and obtain Lmax, Lmin as integrating the noise profile generated from it at every moment. An evalution of the noise prediciton model using field measurements finds good agreement between predicted and measured noise levels at 1m, 8m, 15m from curb of the near side lane.
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- 2011
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260. Radiofrequency Ablation for Hepatocellular Carcinoma Abutting the Diaphragm: Comparison of Effects of Thermal Protection and Therapeutic Efficacy
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Dongil Choi, Hyunchul Rhim, Hyo Keun Lim, Won Jae Lee, Min Woo Lee, Tae Wook Kang, and Young-sun Kim
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Adult ,Male ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Percutaneous ,Radiofrequency ablation ,Diaphragm ,Diaphragmatic breathing ,Lung injury ,law.invention ,Postoperative Complications ,law ,Ascites ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Ultrasonography, Interventional ,Aged ,Chi-Square Distribution ,business.industry ,Liver Neoplasms ,General Medicine ,Middle Aged ,medicine.disease ,Diaphragm (structural system) ,Treatment Outcome ,Effusion ,Case-Control Studies ,Hepatocellular carcinoma ,Catheter Ablation ,Female ,Radiology ,medicine.symptom ,Burns ,Tomography, X-Ray Computed ,business - Abstract
This study was designed to assess the effect of artificial ascites on thermal protection of the diaphragm and the therapeutic efficacy of this technique during percutaneous radiofrequency ablation for hepatocellular carcinoma abutting the diaphragm.A total of 44 patients with a single nodular hepatocellular carcinoma (4 cm; mean, 2.2 cm) that abutted the diaphragm were treated with ultrasound-guided percutaneous radiofrequency ablation as first-line treatment. The patients were divided into two groups: a group who received artificial ascites (n = 20) and a control group (n = 24). We compared the two groups in an assessment for change in diaphragmatic thickness, right shoulder pain, and transient lung injury as indicators of thermal injury to the diaphragm. We evaluated therapeutic efficacy with follow-up CT.Swelling of diaphragm at immediate follow-up CT was more severe in the control group (mean change in thickness, 0.56 mm versus 1.55 mm; p = 0.01). Right shoulder pain (n = 1 versus n = 7) and transient lung injury (n = 0 versus n = 6) occurred statistically significantly more often in the control group than the artificial ascites group, but pleural effusion did not (n = 13 versus n = 1). The technical success rate was higher in the artificial ascites group (100% versus 79%, p = 0.06). There was no significant difference in effectiveness rate of the primary technique (100% versus 92%, p = 0.49) or rate of local tumor progression (20% versus 30%, p = 0.47).The use of artificial ascites for percutaneous radiofrequency ablation of hepatocellular carcinoma abutting the diaphragm had a significant effect on thermal protection of the diaphragm but not on therapeutic efficacy.
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- 2011
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261. Genome-wide association of serum bilirubin levels in Korean population
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Jong-Won Kim, Tae-Wook Kang, Yong Sung Kim, Hee-Jin Kim, Ka-Kyung Kim, Si-Woo Lee, Yeo-Jin Jeon, Jeong-Hwan Kim, Hyoungseok Ju, Han-Chul Lee, Jong Yeol Kim, and Seon-Young Kim
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Adult ,Male ,Adolescent ,Bilirubin ,Single-nucleotide polymorphism ,Genome-wide association study ,Organic Anion Transporters, Sodium-Independent ,Biology ,Polymorphism, Single Nucleotide ,White People ,Cohort Studies ,Solute Carrier Organic Anion Transporter Family Member 1B3 ,Young Adult ,chemistry.chemical_compound ,Asian People ,Statistical significance ,Genetic variation ,Genetics ,Humans ,Glucuronosyltransferase ,Molecular Biology ,Genetics (clinical) ,Aged ,Genetic association ,Aged, 80 and over ,Association Studies Articles ,Genetic Variation ,General Medicine ,Middle Aged ,chemistry ,Cohort ,biology.protein ,Female ,SLCO1B1 ,Genome-Wide Association Study - Abstract
A large-scale, genome-wide association study was performed to identify genetic variations influencing serum bilirubin levels using 8841 Korean individuals. Significant associations were observed at UGT1A1 (rs11891311, P = 4.78 x 10(-148)) and SLCO1B3 (rs2417940, P = 1.03 x 10(-17)), which are two previously identified loci. The two single-nucleotide polymorphisms (SNPs) were replicated (rs11891311, P = 3.18 x 10(-15)) or marginally significant (rs2417940, P = 8.56 x 10(-4)) in an independent cohort of 1096 individuals. In a conditional analysis adjusted for the top UGT1A1 variant (rs11891311), another variant in UGT1A1 (rs4148323, P = 1.22 x 10(-121)) remained significant; this suggests that in UGT1A1 at least two independent genetic variations influence the bilirubin levels in the Korean population. The protein coding variant rs4148323, which is monomorphic in European-derived populations, may be specifically associated with serum bilirubin levels in Asians (P = 2.56 x 10(-70)). The SLCO1B3 variant (rs2417940, P = 1.67 x 10(-18)) remained significant in a conditional analysis for the top UGT1A1 variant. Interestingly, there were significant differences in the associated variations of SLCO1B3 between Koreans and European-derived populations. While the variant rs2417940 at intron 7 of SLCO1B3 was more significantly associated in Koreans, variants rs17680137 (P = 0.584) and rs2117032 (P = 2.76 x 10(-5)), two of the top-ranked SNPs in European-derived populations, did not reach the genome-wide significance level. Also, variants in SLCO1B1 did not reach genome-wide significance in Koreans. Our result supports the idea that there are considerable ethnic differences in genetic association of bilirubin levels between Koreans and European-derived populations.
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- 2010
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262. Energy Management Integrated Circuit for Multi-Source Energy Harvesters in WBAN Applications
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Tae-Wook Kang, Mi Jeong Park, In Gi Lim, Kwang-Il Oh, Jae-Jin Lee, Sungeun Kim, and Hyung-Il Park
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energy management ,Semiconductor device fabrication ,Computer science ,Energy management ,Wearable computer ,02 engineering and technology ,Integrated circuit ,energy harvester ,lcsh:Technology ,law.invention ,lcsh:Chemistry ,law ,Body area network ,0202 electrical engineering, electronic engineering, information engineering ,General Materials Science ,lcsh:QH301-705.5 ,Instrumentation ,Wearable technology ,Fluid Flow and Transfer Processes ,lcsh:T ,business.industry ,human body ,multi-source ,Process Chemistry and Technology ,020208 electrical & electronic engineering ,General Engineering ,Electrical engineering ,021001 nanoscience & nanotechnology ,lcsh:QC1-999 ,Computer Science Applications ,lcsh:Biology (General) ,lcsh:QD1-999 ,lcsh:TA1-2040 ,Electric power ,WBAN ,lcsh:Engineering (General). Civil engineering (General) ,0210 nano-technology ,business ,lcsh:Physics ,Energy (signal processing) - Abstract
This paper presents an energy management integrated circuit for multiple energy harvesters in wireless body area network applications. The electrical power acquired from a single energy harvester around a human body is limited to micro watts, which is insufficient to drive a wearable electronic device. To increase this small amount, the energy from a number of harvesters has to be combined. By combining the energy from multiple distributed harvesters, each one producing negligible energy, significant energy for wearable devices can be obtained. In designing an energy management circuit for a wearable device, there are two issues to be resolved. The first is related to the power consumption of the circuit, and the second issue is related to the methods needed to manage the wide range of power that occurs as the energy input changes during harvesting. In this paper, an energy management circuit that resolves the two issues above is described. The circuit was integrated using 0.13 µ, m Taiwan Semiconductor Manufacturing Company complementary metal-oxide-semiconductor technology. The energy management circuit is designed to combine up to three sources of harvested energy with more than 90% operating efficiency over the entire power range of the energy harvested.
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- 2018
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263. Radiofrequency ablation versus surgical resection for multiple HCCs meeting the Milan criteria: propensity score analyses of 10-year therapeutic outcomes
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D.H. Sinn, D.I. Cha, Insuk Sohn, Jong Man Kim, Min Woo Lee, Kyoung Doo Song, Ji Hye Min, Hyunchul Rhim, and Tae Wook Kang
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Adult ,Male ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Radiofrequency ablation ,medicine.medical_treatment ,Milan criteria ,Gastroenterology ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,law ,Internal medicine ,medicine ,Hepatectomy ,Humans ,Radiology, Nuclear Medicine and imaging ,Stage (cooking) ,Survival rate ,Aged ,Retrospective Studies ,Aged, 80 and over ,Radiofrequency Ablation ,business.industry ,Liver Neoplasms ,Hazard ratio ,Retrospective cohort study ,General Medicine ,Middle Aged ,Survival Rate ,Treatment Outcome ,Liver ,030220 oncology & carcinogenesis ,Propensity score matching ,Female ,030211 gastroenterology & hepatology ,business ,Follow-Up Studies - Abstract
Aim To assess the long-term therapeutic outcomes of radiofrequency ablation (RFA) versus surgical resection (SR) as a first-line treatment for patients meeting the Milan criteria with multiple hepatocellular carcinomas (HCCs). Materials and methods This retrospective study was approved by the institutional review board and the requirement for informed consent was waived. Between January 2004 and December 2009, among 3,441 patients with treatment-naive HCCs, 88 patients meeting the Milan criteria with multiple HCCs (Barcelona Clinic Liver Cancer [BCLC] A stage) who underwent either RFA (n=62) or SR (n=26) were included. Recurrence-free survival (RFS) and overall survival (OS) rates were compared by using propensity score matching. In addition, multivariate analysis was performed for assess the prognostic factor. Results Matching yielded 20 matched pairs of patients. In the two matched groups, the RFS rates were 30% and 30% at 5- and 10-years, respectively, in the RFA group and 60% and 48.6% in the SR group (p=0.054). The corresponding OS rates were 63.3% and 46.1% in the RFA group and 100% and 73.6% in the SR group, respectively (p=0.061). In multivariate analysis, treatment type was independently associated with RFS (hazard ratio [HR]=0.51; p=0.043) whereas it was not a statistically significant factor for OS (HR=0.50; p=0.088). Conclusion In patients meeting the Milan criteria with multiple HCCs (BCLC A stage), SR may provide better RFS compared to RFA.
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- 2018
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264. Percutaneous Radiofrequency Ablation for Hepatic Tumors Abutting the Diaphragm: Clinical Assessment of the Heat-Sink Effect of Artificial Ascites
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Yulri Park, Sang Yu Nam, Hyunchul Rhim, Young-sun Kim, Ilsoo Chang, Dongil Choi, Hyo Keun Lim, Min Woo Lee, Won Jae Lee, and Tae Wook Kang
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Male ,medicine.medical_specialty ,Percutaneous ,Artificial ascites ,Radiofrequency ablation ,medicine.medical_treatment ,Diaphragm ,Catheter ablation ,law.invention ,law ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Electrodes ,Ultrasonography, Interventional ,Aged ,Retrospective Studies ,Chi-Square Distribution ,business.industry ,Liver Neoplasms ,Ascites ,General Medicine ,Middle Aged ,medicine.disease ,Ablation ,Diaphragm (structural system) ,Treatment Outcome ,Hepatocellular carcinoma ,Catheter Ablation ,Disease Progression ,Female ,Radiology ,Tomography, X-Ray Computed ,business ,Ablation zone - Abstract
This study was designed to assess whether artificial ascites has a heat-sink effect on the ablation zone for percutaneous radiofrequency ablation (RFA) of hepatic tumors abutting the diaphragm.We retrospectively assessed 28 patients who underwent percutaneous RFA for the treatment of a single nodular hepatic tumor that abutted the diaphragm from July 2000 to December 2006. All patients underwent ultrasound-guided RFA using internally cooled electrodes. A single ablation for 12 minutes was applied using 3-cm active-tip electrodes. We divided patients into two groups on the basis of whether artificial ascites was introduced before RFA: Group A consisted of patients who received artificial ascites with a mean of 760 mL of a 5% dextrose in water solution (n = 15) and group B consisted of patients who did not receive artificial ascites (n = 13). The volume of the ablation zone was measured on CT images obtained immediately after the ablation procedure, and imaging findings were compared for both groups using the Student's t test. We also compared the local tumor progression rate between both groups using the chi-square test (mean follow-up, 37.4 months).There was no significant difference between the two patient groups with regard to age, sex, Child-Pugh class, or tumor location (p0.05). The tumors were significantly smaller in group A patients (mean +/- SD, 1.6 +/- 0.5 cm) than in group B patients (2.1 +/- 0.7 cm) (p = 0.019). The mean volume of the RFA zone was 31.6 +/- 11.9 cm(3) in group A patients and 30.9 +/- 11.0 cm(3) in group B patients. There was no significant difference between the groups in the ablation volume (p = 0.871). Local tumor progression was noted in four patients (26.7%) in group A and in three patients (23.1%) in group B. There was no significant difference in the local tumor progression rate between the two groups (p = 0.83).Artificial ascites did not show a heat-sink effect on the volume of the ablation zone after percutaneous RFA for the treatment of a hepatic tumor abutting the diaphragm.
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- 2010
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265. Follicular Dendritic Cell Sarcoma of the Abdomen: the Imaging Findings
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Soon Jin Lee, Hye Jong Song, and Tae Wook Kang
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Abdomen, CT ,Male ,Radiography, Abdominal ,Pathology ,medicine.medical_specialty ,Colon ,Spleen ,Case Report ,Dendritic Cell Sarcoma, Follicular ,Diagnosis, Differential ,Abdomen ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Retroperitoneal Space ,Abdomen, neoplasms ,Dyspepsia ,Aged ,Ultrasonography ,Gastrointestinal tract ,Follicular dendritic cells ,business.industry ,Sarcoma ,Middle Aged ,medicine.disease ,Abdominal Pain ,medicine.anatomical_structure ,Tonsil ,Follicular dendritic cell sarcoma ,Abdomen, US ,Abdominal Neoplasms ,Colonic Neoplasms ,Female ,Lymph ,Lymph Nodes ,business ,Gastrointestinal Hemorrhage ,Tomography, X-Ray Computed ,Dendritic Cells, Follicular - Abstract
Follicular dendritic cell sarcoma is a rare neoplasm that originates from follicular dendritic cells in lymphoid follicles. This disease usually involves the lymph nodes, and especially the head and neck area. Rarely, extranodal sites may be affected, including tonsil, the oral cavity, liver, spleen and the gastrointestinal tract. We report here on the imaging findings of follicular dendritic cell sarcoma of the abdomen that involved the retroperitoneal lymph nodes and colon. It shows as a well-defined, enhancing homogenous mass with internal necrosis and regional lymphadenopathy.
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- 2010
266. Percutaneous Radiofrequency Ablation for the Hepatocellular Carcinoma Abutting the Diaphragm: Assessment of Safety and Therapeutic Efficacy
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Young-sun Kim, Eun Young Kim, Dongil Choi, Hyo Keun Lim, Won Jae Lee, Tae Wook Kang, and Hyunchul Rhim
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Adult ,Male ,medicine.medical_specialty ,Percutaneous ,Carcinoma, Hepatocellular ,Pleural effusion ,Radiofrequency ablation ,Hepatocellular carcinoma ,medicine.medical_treatment ,Diaphragm ,law.invention ,Young Adult ,law ,Shoulder Pain ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Computed tomography (CT) ,Ultrasonography ,Aged ,Aged, 80 and over ,business.industry ,Liver Neoplasms ,Lung Injury ,Middle Aged ,medicine.disease ,Hemothorax ,Ablation ,Diaphragm (structural system) ,Surgery ,Treatment Outcome ,Catheter Ablation ,Original Article ,Female ,business ,Complication ,Burns - Abstract
Objective: To assess the safety and therapeutic efficacy of a percutaneous radiofrequency (RF) ablation for the hepatocellular carcinoma (HCC) abutting the diaphragm. Materials and Methods: We retrospectively assessed 80 patients who underwent a percutaneous RF ablation for a single nodular (< 4 cm) HCC over the last four years. Each patient underwent an ultrasound-guided RF ablation using internally cooled electrodes for the first-line treatment. We divided patients into two subgroups based on whether the index tumor was abutting (less than 5 mm) the diaphragm or not: group A (abutting; n = 31) versus group B (non-abutting; n = 49). We compared the two subgroups for complications and therapeutic efficacy using image and the review of medical records. The statistical assessment included an independent t-test, Fisher’s exact test, and chi-square test. Results: The assessment of the diaphragmatic swelling at CT immediately following the procedure was more severe in group A than group B (mean thickness change:1.44 vs. 0.46 mm, p = 0.00). Further, right shoulder pain was more common in group A than B (p = 0.01). Although minor complications (hemothorax 1 case, pleural effusion 1 case) were noted only in group A, no major thoracic complication occurred in either group. The technical success rate was lower in group A than group B (84% vs. 98%, p = 0.03). As well, the primary and secondary technique effectiveness rates in group A and group B were 90% versus 98% (p = 0.29) and 79% versus 91% (p = 0.25), respectively. The local tumor progression rate was higher in group A than in group B (29% vs. 6%, p = 0.02). Conclusion: We found that the percutaneous RF ablation for the HCC abutting the diaphragm is a safe procedure without major complications. However, it is less effective with regard to technical success and local tumor control.
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- 2009
267. Recent Advances in Tumor Ablation for Hepatocellular Carcinoma
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Hyunchul Rhim and Tae Wook Kang
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Oncology ,medicine.medical_specialty ,Hepatology ,medicine.diagnostic_test ,Radiofrequency ablation ,business.industry ,medicine.medical_treatment ,Microwave ablation ,Magnetic resonance imaging ,Irreversible electroporation ,Ablation ,medicine.disease ,law.invention ,law ,Internal medicine ,Hepatocellular carcinoma ,medicine ,Medical imaging ,Stage (cooking) ,Locoregional Therapy for HCC: Review ,business - Abstract
Image-guided tumor ablation for early stage hepatocellular carcinoma (HCC) is an accepted non-surgical treatment that provides excellent local tumor control and favorable survival benefit. This review summarizes the recent advances in tumor ablation for HCC. Diagnostic imaging and molecular biology of HCC has recently undergone marked improvements. Second-generation ultrasonography (US) contrast agents, new computed tomography (CT) techniques, and liver-specific contrast agents for magnetic resonance imaging (MRI) have enabled the early detection of smaller and inconspicuous HCC lesions. Various imaging-guidance tools that incorporate imaging-fusion between real-time US and CT/MRI, that are now common for percutaneous tumor ablation, have increased operator confidence in the accurate targeting of technically difficult tumors. In addition to radiofrequency ablation (RFA), various therapeutic modalities including microwave ablation, irreversible electroporation, and high-intensity focused ultrasound ablation have attracted attention as alternative energy sources for effective locoregional treatment of HCC. In addition, combined treatment with RFA and chemoembolization or molecular agents may be able to overcome the limitation of advanced or large tumors. Finally, understanding of the biological mechanisms and advances in therapy associated with tumor ablation will be important for successful tumor control. All these advances in tumor ablation for HCC will result in significant improvement in the prognosis of HCC patients. In this review, we primarily focus on recent advances in molecular tumor biology, diagnosis, imaging-guidance tools, and therapeutic modalities, and refer to the current status and future perspectives for tumor ablation for HCC.
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- 2015
268. Safety of Percutaneous Biopsy for Hepatic Angiosarcoma: Results of a Multicenter Korean Survey
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Sanghyeok Lim, Chansik An, Min Woo Lee, Sin-Ho Jung, Jung Gu Park, Myeong-Jin Kim, Tae Wook Kang, So Jung Lee, Jung Wook Seo, Dongil Choi, and Ijin Joo
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Adult ,Image-Guided Biopsy ,Male ,medicine.medical_specialty ,Percutaneous ,Blood transfusion ,medicine.medical_treatment ,Hemangiosarcoma ,Hemorrhage ,Severity of Illness Index ,030218 nuclear medicine & medical imaging ,Hospitals, University ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Predictive Value of Tests ,Risk Factors ,Biopsy ,Republic of Korea ,Odds Ratio ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Embolization ,Ultrasonography, Interventional ,Aged ,Retrospective Studies ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Incidence ,Liver Neoplasms ,Retrospective cohort study ,Interventional radiology ,Middle Aged ,Immunohistochemistry ,Surgery ,Diffusion Magnetic Resonance Imaging ,Logistic Models ,Health Care Surveys ,Multivariate Analysis ,030211 gastroenterology & hepatology ,Female ,Radiology ,Biopsy, Large-Core Needle ,Cardiology and Cardiovascular Medicine ,business ,Complication - Abstract
Purpose To evaluate the incidence of severe bleeding and mortality associated with percutaneous biopsy for hepatic angiosarcoma in a multicenter retrospective cohort. Materials and Methods A retrospective review of 33 patients with biopsy-proven hepatic angiosarcoma (29 male; median age, 57 y; age range, 24–96 y) was performed at seven tertiary academic hospitals between January 1998 and March 2015. The mean maximum tumor size was 5.5 cm (range, 1.7–20 cm). An 18-gauge automated cutting biopsy needle was used with a freehand technique in all patients who underwent ultrasonography-guided percutaneous core needle biopsy on an inpatient basis. The incidences of severe bleeding and procedure-related mortality were evaluated per Society of Interventional Radiology (SIR) guidelines. Results There was a mean of 2.8 needle passes per patient during the procedure (range, 1–6). The overall incidence of severe bleeding events (SIR grade C/D) was 9.1% (3 of 33). Two patients were managed with blood transfusion, and one patient underwent embolization for bleeding control. No other major complications were encountered. There were no cases of mortality associated with the biopsy. Conclusions Severe bleeding was not a frequent complication after percutaneous biopsy for hepatic angiosarcoma. The majority of bleeding complications could be controlled with conservative management.
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- 2015
269. Response
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Tae Wook, Kang and Hyo Keun, Lim
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Ablation Techniques ,Male ,Carcinoma, Hepatocellular ,Liver Neoplasms ,Humans ,Female ,Neoplasm Recurrence, Local - Published
- 2015
270. Tumefactive gallbladder sludge: the MRI findings
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Yookyung Kim, Sung Heon Kim, M. Seong, M. Kim, Kyung Mi Jang, Sam Soo Kim, and Tae Wook Kang
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Gadolinium DTPA ,Male ,medicine.medical_specialty ,Contrast Media ,Gallbladder Sludge ,030218 nuclear medicine & medical imaging ,Lesion ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Bile ,Humans ,Radiology, Nuclear Medicine and imaging ,Biliary sludge ,Gallbladder cancer ,Aged ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,Gallbladder ,Reproducibility of Results ,Mean age ,Magnetic resonance imaging ,General Medicine ,Middle Aged ,medicine.disease ,Image Enhancement ,Magnetic Resonance Imaging ,Hyperintensity ,Diffusion Magnetic Resonance Imaging ,030220 oncology & carcinogenesis ,Female ,Radiology ,medicine.symptom ,business ,Mri findings - Abstract
Aim To evaluate the conventional and diffusion-weighted magnetic resonance imaging (MRI) images of tumefactive gallbladder sludge. Materials and methods The institutional review board approved this retrospective study. Between January 2006 and January 2015, 3478 patients were diagnosed with gallbladder sludge by ultrasonography (US). Of them, 12 patients (eight male, four female; mean age, 63.6 years) with 12 tumefactive gallbladder sludge lesions, who underwent subsequent MRI for further evaluation within 1 month, were included in this study. Data regarding the clinical features, presence of enhancement, and signal intensities of the T2-, T1-, and diffusion-weighted images were collected. Results All cases of tumefactive sludge were detected incidentally. None of the patients had any predisposing factors for biliary sludge. The tumefactive gallbladder sludge was predominantly seen as a well-defined mass-like lesion. It showed hyperintensity on T1-weighted images (91.7%, 11/12), and variable signal intensities on T2-weighted images. Most of the tumefactive sludge lesions showed no enhancement on the dynamic phases (90%, 9/10). There were no cases with diffusion restriction. Among the patients with follow-up US data ( n =7), all the lesions were found to have either disappeared or decreased in size. Conclusion Although tumefactive gallbladder sludge on US can mimic gallbladder cancer, its hyperintensity on a T1-weighted image, and the absence of enhancement and diffusion restriction on MRI images can be helpful for differentiating it from a tumorous condition.
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- 2015
271. High-efficiency voltage regulation stage in energy harvesting systems
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Tae Wook Kang, Myung Ae Chung, Kyoungwan Park, Sung-Weon Kang, and Soonchoul Kim
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Power management ,Work (thermodynamics) ,Engineering ,business.industry ,Dissipation ,Power (physics) ,law.invention ,Capacitor ,law ,Control theory ,Voltage regulation ,business ,Energy harvesting ,Voltage - Abstract
A high-efficiency voltage regulation stage in an energy harvesting system is presented. In an energy harvesting system, the availability of energy is uncertain. If energy is harvested from energy resources, the system operates; if not, the system does not work. Therefore, the energy harvesting system starts and stops repeatedly according to the presence or absence of energy. The repeated on and off state in the energy harvesting system decreases operating efficiency which is an important factor in such a system with the limited amount of harvested energy. To improve the efficiency of the system that repeatedly switch between on and off states, the energy dissipated in the transitional state should be minimized. In this work, a voltage regulation stage is implemented with two additional switches, two low power comparators and digital control logic in addition to the conventional regulation stage. The first switch determines the input voltage level of the regulation stage, and the second switch prevents undesired energy dissipation in the boosting state. When the regulation stage supplies power to a 100 ohm load resistor with a 100 uF load capacitor for 50 ms, the efficiency is improved up to 38%, and boosting time is reduced by 42% in comparison with the conventional regulation structure.
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- 2015
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272. Magnetic resonance imaging with gadoxetic acid for local tumour progression after radiofrequency ablation in patients with hepatocellular carcinoma
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Kyung Mi Jang, Kyoung Doo Song, Seong Hyun Kim, Tae Wook Kang, Geum-Youn Gwak, Hyo Keun Lim, Min Woo Lee, Hyunchul Rhim, Jisun Lee, Sin-Ho Jung, and Young-sun Kim
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Adult ,Gadolinium DTPA ,Male ,Gadoxetic acid ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Radiofrequency ablation ,Contrast Media ,Disease-Free Survival ,030218 nuclear medicine & medical imaging ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,law ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Survival rate ,Neuroradiology ,Aged ,Retrospective Studies ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Proportional hazards model ,Hazard ratio ,Liver Neoplasms ,Reproducibility of Results ,Magnetic resonance imaging ,General Medicine ,Middle Aged ,medicine.disease ,Image Enhancement ,Magnetic Resonance Imaging ,Treatment Outcome ,Liver ,030220 oncology & carcinogenesis ,Hepatocellular carcinoma ,Catheter Ablation ,Female ,Radiology ,business ,medicine.drug - Abstract
To develop and validate a prediction model using magnetic resonance imaging (MRI) for local tumour progression (LTP) after radiofrequency ablation (RFA) in hepatocellular carcinoma (HCC) patients. Two hundred and eleven patients who had received RFA as first-line treatment for HCC were retrospectively analyzed. They had undergone gadoxetic acid-enhanced MRI before treatment, and parameters including tumour size; margins; signal intensities on T1-, T2-, and diffusion-weighted images, and hepatobiliary phase images (HBPI); intratumoral fat or tumoral capsules; and peritumoural hypointensity in the HBPI were used to develop a prediction model for LTP after treatment. This model to discriminate low-risk from high-risk LTP groups was constructed based on Cox regression analysis. Our analyses produced the following model: ‘risk score = 0.617 × tumour size + 0.965 × tumour margin + 0.867 × peritumoural hypointensity on HBPI’. This was able to predict which patients were at high risk for LTP after RFA (p
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- 2015
273. Post-ablation des-gamma-carboxy prothrombin level predicts prognosis in hepatitis B-related hepatocellular carcinoma
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Young-sun Kim, Kyoung Doo Song, Tae Wook Kang, Hyunchul Rhim, and Sunyoung Lee
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Male ,Time Factors ,Kaplan-Meier Estimate ,Gastroenterology ,Liver disease ,0302 clinical medicine ,Risk Factors ,Aged, 80 and over ,Univariate analysis ,Hazard ratio ,Liver Neoplasms ,Hepatitis B ,Middle Aged ,Treatment Outcome ,030220 oncology & carcinogenesis ,Hepatocellular carcinoma ,Catheter Ablation ,030211 gastroenterology & hepatology ,Female ,Prothrombin ,alpha-Fetoproteins ,Liver cancer ,Adult ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Risk Assessment ,Disease-Free Survival ,03 medical and health sciences ,Predictive Value of Tests ,Internal medicine ,Republic of Korea ,medicine ,Biomarkers, Tumor ,Humans ,Protein Precursors ,Aged ,Neoplasm Staging ,Proportional Hazards Models ,Retrospective Studies ,Hepatology ,business.industry ,Proportional hazards model ,medicine.disease ,digestive system diseases ,BCLC Stage ,Multivariate Analysis ,Neoplasm Recurrence, Local ,business ,Biomarkers - Abstract
BACKGROUND & AIMS We investigated whether pre- or post-ablation serum alpha-foetoprotein (AFP) and des-gamma-carboxy prothrombin (DCP) levels can predict prognosis in patients with curative radiofrequency ablation (RFA) for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). METHODS We retrospectively analysed 412 patients with HBV-related single HCC treated with percutaneous RFA between January 2004 and December 2013. AFP and DCP levels were measured before (pre-ablation) and 1 month after treatment (post-ablation). We assessed predictive factors for overall and recurrence-free survival. RESULTS On univariate analysis, Child-Pugh score, Model for End-Stage Liver Disease (MELD) score, platelet count, tumour size, Barcelona Clinic Liver Cancer (BCLC) stage, and pre- and post-ablation DCP were significant for overall survival; and age, Child-Pugh score, MELD score, platelet count, tumour size, Cancer of the Liver Italian Program (CLIP) score, BCLC stage, and pre- and post-ablation AFP and DCP were significant for recurrence-free survival. Multivariate analysis revealed significant differences in overall survival by MELD score and tumour size and in recurrence-free survival by BCLC stage. Among the tumour markers, post-ablation DCP was an independent prognostic factor for overall and recurrence-free survival [hazard ratio (HR), 3.438; 95% confidence interval (CI), 1.331-8.877; P = 0.011 and HR, 4.934; 95% CI, 2.761-8.816; P < 0.001 respectively]. Post-ablation AFP was associated with recurrence-free survival (HR, 1.995; 95% CI, 1.476-2.697; P < 0.001) but not overall survival. CONCLUSIONS In patients with HBV-related HCC, post-ablation serum DCP is a useful biomarker for predicting survival and recurrence after curative RFA.
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- 2015
274. Differentiation between pancreatic metastases from renal cell carcinoma and hypervascular neuroendocrine tumour: Use of relative percentage washout value and its clinical implication
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Min-Ji Kim, Jisun Lee, Seong Hyun Kim, Ah Yeong Kim, Dongil Choi, Tae Wook Kang, and Kyung Mi Jang
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Male ,medicine.medical_specialty ,Family Conflict ,Iohexol ,Contrast Media ,Neuroendocrine tumors ,Kidney ,Sensitivity and Specificity ,Metastasis ,Cohort Studies ,Renal cell carcinoma ,Hounsfield scale ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Carcinoma, Renal Cell ,Pancreas ,Aged ,Retrospective Studies ,Aged, 80 and over ,medicine.diagnostic_test ,Receiver operating characteristic ,business.industry ,Reproducibility of Results ,Magnetic resonance imaging ,General Medicine ,Middle Aged ,medicine.disease ,Pancreatic Neoplasms ,Radiographic Image Enhancement ,Neuroendocrine Tumors ,medicine.anatomical_structure ,Female ,Radiology ,Nuclear medicine ,business ,Tomography, X-Ray Computed ,medicine.drug - Abstract
To compare computed tomography (CT) findings in patients with pancreatic metastasis from renal cell carcinoma (pRCC) and patients with hypervascular pancreatic neuroendocrine tumour (pNET) with a focus on the relative percentage washout (RPW).We evaluated 16 patients with 37 pRCCs and 28 patients with 31 hypervascular pNETs using a protocol consisting of arterial and portal phase CT. Imaging findings were analyzed for comparison between the two groups. The RPW of each tumour using biphasic CT was obtained by two observers for evaluation of diagnostic performance. Interobserver agreement of each value and optimal cut-off level of RPW for discrimination between groups were evaluated.Tumour multiplicity showed significant difference in both groups. The mean RPW of the pRCC group (observer 1, 27.0%; observer 2, 29.4%) was significantly higher than that of the pNET group (observer 1, 0.5%; observer 2, 3.2%) (p0.001 for each observer). Interobserver agreement for both attenuation values and RPWs was excellent. A RPW value of 19% was selected as the optimal cut-off for pRCC determination, and showed good performance (accuracy 83.8%, sensitivity 83.8%, and specificity 83.9%).With multiplicity, RPW of the tumour on CT could be helpful for differentiating pRCCs from hypervascular pNETs.
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- 2015
275. Pancreatic Candidiasis That Mimics a Malignant Pancreatic Cystic Tumor on Magnetic Resonance Imaging: A Case Report in an Immunocompetent Patient
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Minjung Seong, Sang Yun Ha, and Tae Wook Kang
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Male ,Pathology ,medicine.medical_specialty ,Case Report ,Diagnosis, Differential ,Immunocompromised Host ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Pancreas ,Candida ,Cystic Tumor ,medicine.diagnostic_test ,business.industry ,Human gastrointestinal tract ,Candidiasis ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Solid component ,Pancreatic Neoplasms ,Radiography ,medicine.anatomical_structure ,Pancreatitis ,Gastrointestinal Imaging ,Cystic mass ,Differential diagnosis ,business ,Infection - Abstract
Candida is a commensal organism that is frequently found in the human gastrointestinal tract. It is the most common organism that causes pancreatic fungal infections. However, magnetic resonance imaging findings of Candida infection in the pancreas have not been described. We report imaging findings of pancreatic candidiasis in a patient in immunocompetent condition. It presented as a multi-septated cystic mass with a peripheral solid component in the background of pancreatitis and restricted diffusion on diffusion-weighted image that mimicked a malignant pancreatic cystic tumor.
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- 2015
276. Graphene oxide-encoded Ag nanoshells with single-particle detection sensitivity towards cancer cell imaging based on SERRS
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DaBin Yim, Jaebum Choo, Yoon-Sik Lee, Homan Kang, Jin Woong Kim, Hye-In Kim, Su-Ji Jeon, Jin-Kyoung Yang, Sangyeop Lee, Jong-Ho Kim, and Tae Wook Kang
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Models, Molecular ,Materials science ,Nanostructure ,Silver ,Surface Properties ,Static Electricity ,Molecular Conformation ,Nanoprobe ,Nanotechnology ,Spectrum Analysis, Raman ,Biochemistry ,Analytical Chemistry ,law.invention ,symbols.namesake ,law ,Limit of Detection ,Electrochemistry ,Environmental Chemistry ,Humans ,Amines ,Spectroscopy ,Graphene ,Nanoshells ,Resonance ,Oxides ,Silicon Dioxide ,Nanoshell ,Molecular Imaging ,symbols ,MCF-7 Cells ,Graphite ,Raman spectroscopy ,Biosensor ,Raman scattering - Abstract
Developing ultrasensitive Raman nanoprobes is one of the emerging interests in the field of biosensing and bioimaging. Herein, we constructed a new type of surface-enhanced resonance Raman scattering nanoprobe composed of an Ag nanoshell as a surface-enhanced Raman scattering-active nanostructure, which was encapsulated with 4,7,10-trioxa-1,13-tridecanediamine-functionalized graphene oxide as an ultrasensitive Raman reporter exhibiting strong resonance Raman scattering including distinct D and G modes. The designed nanoprobe was able to produce much more intense and simpler Raman signals even at a single particle level than the Ag nanoshell bearing a well-known Raman reporter, which is beneficial for the sensitive detection of a target in a complex biological system. Finally, this ultrasensitive nanoprobe successfully demonstrated its potential for bioimaging of cancer cells using Raman spectroscopy.
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- 2015
277. The complete mitogenome ofRhodeus uyekii(Cypriniformes, Cyprinidae)
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Byong-Chul Kim, Moo-Sang Kim, Tae-Wook Kang, and Chang-Bae Kim
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Genetics ,Mitochondrial DNA ,biology ,Phylogenetic tree ,Rhodeus ,biology.organism_classification ,Biochemistry ,Genome ,Rhodeus uyekii ,Endocrinology ,Phylogenetics ,Codon usage bias ,Cypriniformes ,Molecular Biology - Abstract
The complete nucleotide sequence of the mitochondrial genome from the R. uyekii with a total size of 16,817 bp has been determined by long PCR technology. Mitogenome of R. uyekii encoding 13 putative proteins, two ribosomal RNAs and 22 tRNAs shows typical teleost mitogenome structure. Nucleotide composition, amino acid composition and codon usage are in the range of values estimated from other teleost mitogenomes. In the AT rich region of R. uyekii, several conserved blocks which are identified from vertebrates are observed in the genome. R. uyekii, the Korean endemic species, belongs to cyprinid fish from which the information of nine mitogenomes is available. To understand the phylogenetic relationships of Cypriniformes from the known mitogenome information, we analysed Cypriniformes mitogenome based on protein coding gene sequences. In spite of more resolved picture of phylogenetic interrelationships in cyprinid fish in this study, the further study with comprehensive taxon sampling for mitogenome information is strongly needed.
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- 2006
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278. Identification of Arterial Hyperenhancement in CT and MRI in Patients with Hepatocellular Carcinoma: Value of Unenhanced Images.
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Mimi Kim, Tae Wook Kang, Dong Ik Cha, Kyoung Mi Jang, Young Kon Kim, Seong Hyun Kim, Dong Hyun Sinn, and Kyunga Kim
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- 2019
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279. Usefulness of Virtual Expiratory CT Images to Compensate for Respiratory Liver Motion in Ultrasound/CT Image Fusion: A Prospective Study in Patients with Focal Hepatic Lesions.
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Tae Wook Kang, Min Woo Lee, Dong Ik Cha, Hyun Jung Park, Jun Sung Park, Won-Chul Bang, and Seon Woo Kim
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- 2019
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280. Wetting and Interfacial Reaction Investigations of Coke/Slag Systems and Associated Liquid Permeability of Blast Furnaces
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N. Saha-Chaudhury, Veena Sahajwalla, Sushil Gupta, and Tae Wook Kang
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Blast furnace ,Materials science ,Silicon ,Mechanical Engineering ,Metallurgy ,Metals and Alloys ,chemistry.chemical_element ,Slag ,Coke ,Electron microprobe ,Substrate (electronics) ,chemistry ,Mechanics of Materials ,Ground granulated blast-furnace slag ,visual_art ,Materials Chemistry ,visual_art.visual_art_medium ,Wetting - Abstract
An interfacial study between metallurgical coke and synthetic slags representing typical slag chemistry of bosh regions of an operating blast furnace was conducted at 1500°C using a horizontal laboratory furnace. The wetting characteristics of coke with slag was studied by measuring dynamic contact angle of sessile droplet of slag on coke substrate, while reaction kinetics of interface was monitored by measuring the amount of CO and CO2 gases with the help of infrared analyzer. The interface chemistry was also examined by SEM/EDS/EPMA. The study demonstrated that coke wettability was strongly dependent both on the slag composition as well as coke chemistry such that low basicity (CaO/SiO2) of slag, that is high amounts of oxides of silicon enhanced the wetting propensity of slag. The study further showed that the wettability of coke with slag was found to improve with increased extent of gasification, and was attributed to higher ash content of partially gasified cokes. The CO/CO2 measurements of off gases from the reacting chamber were used to demonstrate that slag wettability with coke was primarily controlled by the kinetics of reduction of metal oxides at the slag/coke interface particularly that of silica. The study demonstrates that in addition to slag composition, coke properties could also influence the liquid permeability of lower zone of the blast furnace, and hence needs attention while optimizing the bosh slag composition for high productivity blast furnace operation.
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- 2005
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281. Optimal Design of Strip Casting Roll
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Cheol-Min Park, Gyung-Jin Park, and Tae-Wook Kang
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Optimal design ,Engineering ,business.industry ,Mechanical Engineering ,Process (computing) ,Structural engineering ,Physics::Classical Physics ,Physics::Fluid Dynamics ,Volume (thermodynamics) ,Heat flux ,Casting (metalworking) ,Thermal ,Heat transfer ,Deformation (engineering) ,business - Abstract
In twin roll strip casting process, the design of casting roll is the most important equipment for producing strip. Analyses of heat transfer and deformation for the casting roll are carried out by using the finite element program, ANSYS. Both the elastic deformation and the elasto-plastic deformation under a thermal load are considered in the analysis. Optimization to minimize the volume of roll is performed under the various thermal loads such as the heat flux and the roll speed. Design variables are defined by diameters and positions of the cooling hole in the roll , Although the thermal load remarkably varies, the design variables and objective function are found to be consistent.
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- 2002
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282. Analysis and prevention of microcracking phenomenon occurring during strip casting of an AISI 304 stainless steel
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Hee-Kyung Moon, Sunghak Lee, Seong-In Jeong, Man-Jin Ha, Ju-Tae Choi, and Tae-Wook Kang
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Materials science ,Metallurgy ,Metals and Alloys ,engineering.material ,Condensed Matter Physics ,Colada ,Continuous casting ,Black oxide ,Mechanics of Materials ,Casting (metalworking) ,Coulee ,Pickling ,engineering ,Austenitic stainless steel ,Composite material ,Layer (electronics) - Abstract
This study was concerned with the effects of microstructural parameters on the microcracking phenomenon occurring during strip casting of an AISI 304 stainless steel. Detailed microstructural analyses of the microcracked regions showed that microcracks were formed mainly along tortoise-shell-shaped depressions and that their number and size were considerably reduced when strip casting was done right after a shot-blasting or pickling treatment of the casting roll surface. This microcracking phenomenon was closely related to the formation of a black oxide layer, which was mainly composed of manganese-rich oxides, on the roll surface. The black oxide layer acted as a barrier of thermal transfer between the rolls and melt, led to an increased gas gap and inhomogeneous solidification of cast strips, and, thus, played a role in forming both tortoise-shell—shaped depressions and microcracks on the strip surface. The installation of brush rolls behind the casting rolls was suggested as a method to prevent microcracks, because the brush rolls could continuously scrape off the black oxide layer affixed on the roll surface during strip casting.
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- 2002
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283. Corrigendum to 'Object composite query method using IFC and LandXML based on BIM linkage model' [Autom. Constr. (2017) 14–23]
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Tae Wook Kang
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Engineering drawing ,Engineering ,Control and Systems Engineering ,law ,business.industry ,Building and Construction ,Linkage (mechanical) ,Object (computer science) ,business ,Civil and Structural Engineering ,law.invention - Published
- 2017
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284. The Usefulness of Minimally Invasive Plate Osteosynthesis to Manage Comminuted Mid-Clavicle Fracture: A Comparison with Conventional Open Plating
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Seung Bum Han, Woong Kyo Jeong, Hyun Jung Hwang, Dong Ki Lee, and Tae Wook Kang
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Orthodontics ,030222 orthopedics ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Plate osteosynthesis ,Clavicle ,business.industry ,Plating ,medicine ,Fracture (geology) ,030212 general & internal medicine ,business - Published
- 2017
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285. Clinical outcomes of laparoscopic radiofrequency ablation of single primary or recurrent hepatocellular carcinoma (≤3 cm)
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Jae-Won Joh, Dong Kyu Oh, Byung Gon Na, Hyun Chul Lim, Gyu-Seong Choi, Jong Man Kim, Min Woo Lee, Tae Wook Kang, Kyo-Won Lee, and Choon Hyuck David Kwon
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medicine.medical_specialty ,Percutaneous ,Hepatocellular carcinoma ,Radiofrequency ablation ,Local neoplasm recurrence ,medicine.medical_treatment ,Technical success ,Catheter ablation ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,law ,Medicine ,Laparoscopy ,medicine.diagnostic_test ,business.industry ,Operative mortality ,medicine.disease ,Recurrent Hepatocellular Carcinoma ,surgical procedures, operative ,030220 oncology & carcinogenesis ,Original Article ,030211 gastroenterology & hepatology ,Surgery ,Radiology ,business ,therapeutics - Abstract
Purpose Percutaneous radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) has some limitations such as poor sonic window and injury to adjacent organs. The laparoscopic approach has been suggested as an alternative option. The aim of this study was to show the safety and efficacy of laparoscopic RFA for single, small (≤3 cm), and primary or recurrent HCC that is not suitable for percutaneous RFA or surgical resection. Methods We reviewed the cases of 37 patients (32 men and 5 women, mean age 61 ± 8.1 years) who underwent laparoscopic RFA for single, small HCC (≤3 cm) that was unsuitable for percutaneous RFA or surgical resection. Results The technical success rate was 94.6% and 34 patients (95%) had no complications. There were no conversions to open RFA and no operative mortality. The primary effectiveness rate 1 month after the procedure was 100%. The overall recurrence rates at 3, 6, 12, and 24 months after the laparoscopic RFA were 8.1%, 14.4%, 25%, and 35.7%, respectively. The local tumor progression rate was 4.2% at 6 months and 8.7% at 9 months. Conclusion Laparoscopic RFA is a safe and effective treatment for HCC cases that are unsuitable for percutaneous RFA.
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- 2017
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286. Added Value of Contrast-Enhanced Ultrasound on Biopsies of Focal Hepatic Lesions Invisible on Fusion Imaging Guidance
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Seong Hyun Kim, Sang Yun Ha, Seung Soo Kim, Tae Wook Kang, Min Woo Lee, Mimi Kim, and Kyoung Doo Song
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Adult ,Male ,medicine.medical_specialty ,Percutaneous ,Sonazoid ,Biopsy ,Iron ,Clinical Decision-Making ,Contrast Media ,Ferric Compounds ,030218 nuclear medicine & medical imaging ,Lesion ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Positron Emission Tomography Computed Tomography ,medicine ,Contrast-enhanced ultrasonography ,Humans ,Radiology, Nuclear Medicine and imaging ,Endoscopic Ultrasound-Guided Fine Needle Aspiration ,Aged ,Retrospective Studies ,Aged, 80 and over ,Image fusion ,medicine.diagnostic_test ,business.industry ,Liver Diseases ,Oxides ,Retrospective cohort study ,Magnetic resonance imaging ,Fusion imaging ,Middle Aged ,Institutional review board ,Liver ,030220 oncology & carcinogenesis ,Gastrointestinal Imaging ,Original Article ,Female ,Radiology ,medicine.symptom ,business ,Contrast-enhanced ultrasound - Abstract
Objective To assess whether contrast-enhanced ultrasonography (CEUS) with Sonazoid can improve the lesion conspicuity and feasibility of percutaneous biopsies for focal hepatic lesions invisible on fusion imaging of real-time ultrasonography (US) with computed tomography/magnetic resonance images, and evaluate its impact on clinical decision making. Materials and Methods The Institutional Review Board approved this retrospective study. Between June 2013 and January 2015, 711 US-guided percutaneous biopsies were performed for focal hepatic lesions. Biopsies were performed using CEUS for guidance if lesions were invisible on fusion imaging. We retrospectively evaluated the number of target lesions initially invisible on fusion imaging that became visible after applying CEUS, using a 4-point scale. Technical success rates of biopsies were evaluated based on histopathological results. In addition, the occurrence of changes in clinical decision making was assessed. Results Among 711 patients, 16 patients (2.3%) were included in the study. The median size of target lesions was 1.1 cm (range, 0.5–1.9 cm) in pre-procedural imaging. After CEUS, 15 of 16 (93.8%) focal hepatic lesions were visualized. The conspicuity score was significantly increased after adding CEUS, as compared to that on fusion imaging (p < 0.001). The technical success rate of biopsy was 87.6% (14/16). After biopsy, there were changes in clinical decision making for 11 of 16 patients (68.8%). Conclusion The addition of CEUS could improve the conspicuity of focal hepatic lesions invisible on fusion imaging. This dual guidance using CEUS and fusion imaging may affect patient management via changes in clinical decision-making.
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- 2017
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287. New Radiofrequency Device to Reduce Bleeding after Core Needle Biopsy: Experimental Study in a Porcine Liver Model
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Young-sun Kim, Tae Wook Kang, Min Woo Lee, Hyo Keun Lim, Sanghyeok Lim, Hyunchul Rhim, and Kyoung Doo Song
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Image-Guided Biopsy ,Core needle ,medicine.medical_specialty ,Complications ,Swine ,Radiofrequency ablation ,Biopsy ,medicine.medical_treatment ,Hemorrhage ,030218 nuclear medicine & medical imaging ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,In vivo ,law ,Porcine liver ,Animals ,Medicine ,Radiology, Nuclear Medicine and imaging ,Electrodes ,Experimental study ,medicine.diagnostic_test ,Heparin ,business.industry ,Temperature ,Core biopsy tract ablation ,Ablation ,Pulsed Radiofrequency Treatment ,Liver ,030220 oncology & carcinogenesis ,Hemostasis ,Gastrointestinal Imaging ,Original Article ,Female ,Biopsy, Large-Core Needle ,Radiology ,business - Abstract
Objective To evaluate the in vivo efficiency of the biopsy tract radiofrequency ablation for hemostasis after core biopsy of the liver in a porcine liver model, including situations with bleeding tendency and a larger (16-gauge) core needle. Materials and Methods A preliminary study was performed using one pig to determine optimal ablation parameters. For the main experiment, four pigs were assigned to different groups according to heparinization use and biopsy needle caliber. In each pig, 14 control (without tract ablation) and 14 experimental (tract ablation) ultrasound-guided core biopsies were performed using either an 18- or 16-gauge needle. Post-biopsy bleeding amounts were measured by soaking up the blood for five minutes. The results were compared using the Mann-Whitney U test. Results The optimal parameters for biopsy tract ablation were determined as a 2-cm active tip electrode set at 40-watt with a tip temperature of 70–80℃. The bleeding amounts in all experimental groups were smaller than those in the controls; however they were significant in the non-heparinized pig biopsied with an 18-gauge needle and in two heparinized pigs (p < 0.001). In the heparinized pigs, the mean blood loss in the experimental group was 3.5% and 13.5% of the controls biopsied with an 18- and 16-gauge needle, respectively. Conclusion Radiofrequency ablation of hepatic core biopsy tract ablation may reduce post-biopsy bleeding even under bleeding tendency and using a larger core needle, according to the result from in vivo porcine model experiments.
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- 2017
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288. Value of diffusion-weighted MRI for differentiating malignant from benign intraductal papillary mucinous neoplasms of the pancreas
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Dongil Choi, Sanghyeok Lim, Kyung Mi Jang, Seong Hyun Kim, Tae Wook Kang, Soon Jin Lee, and Ji Hye Min
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Adult ,Gadolinium DTPA ,Male ,medicine.medical_specialty ,Contrast Media ,Malignancy ,Sensitivity and Specificity ,Diagnosis, Differential ,symbols.namesake ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Fisher's exact test ,Aged ,Aged, 80 and over ,Observer Variation ,Intraductal papillary mucinous neoplasm ,business.industry ,Curve analysis ,Reproducibility of Results ,General Medicine ,medicine.disease ,Predictive value ,Adenocarcinoma, Mucinous ,Pancreatic Neoplasms ,medicine.anatomical_structure ,Diffusion Magnetic Resonance Imaging ,symbols ,Female ,Radiology ,Pancreas ,business ,Area under the roc curve ,Diffusion MRI ,Carcinoma, Pancreatic Ductal - Abstract
The purpose of this study was to evaluate whether the use of diffusion-weighted MRI (DWI) increases diagnostic accuracy in the differentiation of malignant from benign intraductal papillary mucinous neoplasms (IPMNs) of the pancreas over the accuracy of contrast-enhanced MRI with MRCP.A total of 61 patients with surgically resected IPMNs (19 malignant, 42 benign) who underwent gadoxetic acid-enhanced MRI, DWI, and MRCP were included. Two blinded observers evaluated two image sets, that is, conventional MRI with MRCP images versus combined conventional MRI with MRCP and DW images, and scored their confidence for malignancy of IPMNs. Qualitative analyses of the IPMNs were also conducted. Diagnostic performance (ROC curve analysis), accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were evaluated. The Fisher exact test was used to compare groups.The diagnostic performance (area under the ROC curve [Az]) with respect to predicting malignancy of IPMNs improved significantly for both observers after additional review of DW images (p0.05). The diagnostic accuracy, sensitivity, specificity, PPV, and NPV of combined conventional and DW images were higher than those of conventional MR images alone. Diffusion restriction was more often present in malignant IPMNs (78.9%) than in benign IPMNs (16.7%) (p0.001) with excellent interobserver agreement (ĸ = 0.965).Compared with conventional MRI alone, adding DWI to conventional MRI improves diagnostic accuracy with increased specificity for differentiating malignant from benign IPMNs of the pancreas.
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- 2014
289. Improving data rate in the human body communications
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In-Gi Lim, Sung Eun Kim, Kyung-Hwan Park, Sung-Weon Kang, and Tae Wook Kang
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business.industry ,Computer science ,Human body ,Telecommunications ,business ,Data rate - Published
- 2014
- Full Text
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290. Value of gadoxetic acid-enhanced and diffusion-weighted MR imaging in evaluation of hepatocellular carcinomas with atypical enhancement pattern on contrast-enhanced multiphasic MDCT in patients with chronic liver disease
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Dongil Choi, Tae Wook Kang, Cheol Keun Park, Kyoung Doo Song, Hyun Su Kim, and Seong Hyun Kim
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Adult ,Gadolinium DTPA ,Male ,Gadoxetic acid ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,media_common.quotation_subject ,Contrast Media ,Chronic liver disease ,Sensitivity and Specificity ,End Stage Liver Disease ,Multidetector Computed Tomography ,Medicine ,Contrast (vision) ,Humans ,Radiology, Nuclear Medicine and imaging ,In patient ,media_common ,Aged ,Chi-Square Distribution ,business.industry ,Liver Neoplasms ,General Medicine ,HCCS ,Middle Aged ,medicine.disease ,Hyperintensity ,Exact test ,Diffusion Magnetic Resonance Imaging ,Hepatocellular carcinoma ,Female ,Radiology ,business ,medicine.drug - Abstract
The purpose of this study was to investigate the value of enhancement kinetics and ancillary imaging findings on gadoxetic acid-enhanced and diffusion-weighted (DW) MR imaging for diagnosing hepatocellular carcinomas (HCCs) without the typical enhancement pattern on contrast-enhanced multiphasic MDCT in patients with chronic liver disease.Eighty-two surgically confirmed HCCs without the typical enhancement pattern (hypervascular in the arterial phase, followed by washout on the portal or equilibrium phases) on triple-phase MDCT were enrolled in this study. The patients were classified into four categories based on the CT density pattern of arterial and equilibrium phases (isodense-isodense, hypodense-hypodense, isodense-hypodense, and hyperdense-isodense) compared to liver parenchyma. Signal intensity of HCCs on T2-weighted images (T2WI), arterial phase, 3 min late-phase, hepatobiliary phase (HBP) and DW images with a b value of 800 s/mm2 were qualitatively evaluated, and ADC values were measured. Fisher's exact test and Chi-square test were used to compare the frequency and trend of hyperintensity on T2WI, hypointensity on HBP images, hyperintensity on DW images, and histopathologic grades between groups with different CT density patterns. Kruskal-Wallis test was used to compare the ADC value between groups.Thirty and 52 HCCs were categorized as hypervascular (hyperdense-isodense) and non-hypervascular HCCs (3, isodense-isodense; 37, hypodense-hypodense; 12, isodense-hypodense), respectively. Most HCCs showed hyperintensity on T2WI (77/82, 93.9%) and DW images (81/82, 98.8%) and hypointensity on HBP images (80/82, 97.6%). Thirty-eight HCCs (38/82, 46.3%) showed typical HCC enhancement pattern on dynamic MR images. There were no significant differences in the frequency and trend of signal intensity on T2WI, HBP images, DW images, and histopathologic grades with regard to the four CT density patterns (p0.05). No significant difference in mean ADC values between groups was identified (p0.05).Gadoxetic acid-enhanced and DW MR imaging can help diagnose HCCs with atypical enhancement patterns on multiphasic CT in patients with chronic liver disease.
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- 2014
291. Genome-wide profiling of the microRNA-mRNA regulatory network in skeletal muscle with aging
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Seungmin Lee, Ki Sun Kwon, So Hee Dho, Seon-Young Kim, Young-Kyu Park, Ji-Young Kim, Hee Jin Kim, Kwang-Pyo Lee, and Tae-Wook Kang
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Male ,Aging ,Muscle Proteins ,Skeletal muscle ,Biology ,imprinted Dlk1-Dio3 ,Mice ,microRNA cluster ,Transcription (biology) ,microRNA ,medicine ,Animals ,RNA, Messenger ,Kinase activity ,Muscle, Skeletal ,Chromosome 12 ,Regulation of gene expression ,Genetics ,Messenger RNA ,Genome ,novel microRNA ,Gene Expression Profiling ,microRNA profiling ,Cell Biology ,medicine.disease ,Cell biology ,MicroRNAs ,medicine.anatomical_structure ,Gene Expression Regulation ,Sarcopenia ,Research Paper - Abstract
Skeletal muscle degenerates progressively, losing mass (sarcopenia) over time, which leads to reduced physical ability and often results in secondary diseases such as diabetes and obesity. The regulation of gene expression by microRNAs is a key event in muscle development and disease. To understand genome-wide changes in microRNAs and mRNAs during muscle aging, we sequenced microRNAs and mRNAs from mouse gastrocnemius muscles at two different ages (6 and 24 months). Thirty-four microRNAs (15 up-regulated and 19 down-regulated) were differentially expressed with age, including the microRNAs miR-206 and -434, which were differentially expressed in aged muscle in previous studies. Interestingly, eight microRNAs in a microRNA cluster at the imprinted Dlk1-Dio3 locus on chromosome 12 were coordinately down-regulated. In addition, sixteen novel microRNAs were identified. Integrative analysis of microRNA and mRNA expression revealed that microRNAs may contribute to muscle aging through the positive regulation of transcription, metabolic processes, and kinase activity. Many of the age-related microRNAs have been implicated in human muscular diseases. We suggest that genome-wide microRNA profiling will expand our knowledge of microRNA function in the muscle aging process.
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- 2014
292. Gastrointestinal stromal tumours: correlation of modified NIH risk stratification with diffusion-weighted MR imaging as an imaging biomarker
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Seong Hyun Kim, Tae Wook Kang, Kyung Mi Jang, Sang Yun Ha, Min-Ji Kim, Dongil Choi, Won Ki Kang, and Kyoung-Mee Kim
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Adult ,Gadolinium DTPA ,Male ,Risk ,medicine.medical_specialty ,Imaging biomarker ,Gastrointestinal Stromal Tumors ,Sensitivity and Specificity ,Region of interest ,medicine ,Effective diffusion coefficient ,Humans ,Radiology, Nuclear Medicine and imaging ,Radionuclide Imaging ,Aged ,Gastrointestinal Neoplasms ,Retrospective Studies ,medicine.diagnostic_test ,GiST ,Receiver operating characteristic ,business.industry ,Confounding ,Reproducibility of Results ,Magnetic resonance imaging ,General Medicine ,Middle Aged ,Diffusion Magnetic Resonance Imaging ,ROC Curve ,Female ,Radiology ,Neoplasm Grading ,Nuclear medicine ,business ,Diffusion MRI - Abstract
Purpose To evaluate the correlation of risk grade of gastrointestinal stromal tumours (GISTs) based on modified National Institutes of Health (NIH) criteria with conventional magnetic resonance (MR) imaging and diffusion-weighted (DW) imaging. Methods We included 22 patients with histopathologically proven GISTs in the stomach or small bowel who underwent pre-operative gadoxetic acid-enhanced MR imaging and DW imaging. We retrospectively assessed correlations between morphologic findings, qualitative (signal intensity, consensus from two observers) and quantitative (degree of dynamic enhancement using signal intensity of tumour/muscle ratio and apparent diffusion coefficient [ADC]) values, and the modified NIH criteria for risk stratification. Spearman partial correlation analysis was used to control for tumour size as a confounding factor. The optimal cut-off level of ADC values for intermediate or high risk GISTs was analyzed using a receiver operating characteristic analysis. Results Except tumour size and necrosis, conventional MR imaging findings, including the degree of dynamic enhancement, were not significantly different according to the modified NIH criteria ( p >0.05). Tumour ADC values were negatively correlated with the modified NIH criteria, before and after adjustment of tumour size ( ρ =−0.754; p ρ =−0.513; p =0.017, respectively). The optimal cut-off value for the determination of intermediate or high-risk GISTs was 1.279×10 −3 mm 2 /s (100% sensitivity, 69.2% specificity, 81.8% accuracy). Conclusion Except tumour size and necrosis, conventional MR imaging findings did not correlate with the risk grade. However, the ADC value can be used as an imaging biomarker to assess the risk grade of GISTs, regardless of tumour size.
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- 2014
293. Project Cost Estimation of National Road in Preliminary Feasibility Stage Using BIM/GIS Platform
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T. Park, Y. Lee, K. Seo, and Tae-Wook Kang
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Transport engineering ,Engineering ,Geographic information system ,Building information modeling ,Cost estimate ,Feasibility study ,Integrated project delivery ,business.industry ,Mining feasibility study ,Environmental impact assessment ,business ,Bridge (nautical) - Abstract
A preliminary feasibility study evaluates various aspects of a project, such as environmental assessment, field study, technological validity, and economic feasibility. Among them, economic feasibility is the most important factor to use in selecting a road route in Korea. A proper preliminary feasibility study considers all costs incurred in the life cycle of the project, including construction costs, land acquisition costs, collateral expenses, and operation and maintenance costs. However, only construction costs are traditionally considered in the assessment of the financial viability of national road projects. In addition, while 3D modeling techniques have brought improved designs and engineering processes to the construction industries, their application in preliminary feasibility studies remains rare. The authors have developed a system that employs building information modeling and geographic information systems for estimating the cost of building a national road that can be applied in the preliminary feasibility stage. The proposed system is composed of three modules that estimate construction costs, land acquisition costs, and operations and maintenance (O&M) costs. Based on the road route, the proposed system analyzes cross-sections through the topography and subsequently determines the probable road, bridge, and tunnel sections, and their project costs. Overall, the proposed system could assist a reasonable decision making for best route selection and further facilitate improved project delivery.
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- 2014
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294. Percutaneous radiofrequency ablation of hepatic tumours: factors affecting technical failure of artificial ascites formation using an angiosheath
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M.J. Hye, Sung Hee Lim, Min Woo Lee, K.D. Song, Hyunchul Rhim, Tae Wook Kang, H.K. Lim, and D. I. Cha
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Adult ,Male ,medicine.medical_specialty ,Percutaneous ,Adolescent ,Radiofrequency ablation ,Artificial ascites ,Technical failure ,Punctures ,law.invention ,Cohort Studies ,Young Adult ,law ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Hepatic tumours ,Treatment Failure ,Transcatheter arterial chemoembolization ,Aged ,Retrospective Studies ,Ultrasonography ,Aged, 80 and over ,business.industry ,Liver Neoplasms ,Ascites ,Water ,Retrospective cohort study ,General Medicine ,Middle Aged ,Surgery ,Treatment Outcome ,Liver ,Needles ,Catheter Ablation ,Drainage ,Feasibility Studies ,Equipment Failure ,Female ,business ,Tomography, X-Ray Computed ,Abdominal surgery - Abstract
To evaluate the technical feasibility of artificial ascites formation using an angiosheath before percutaneous radiofrequency ablation (RFA) for hepatic tumours and to determine predictive factors affecting the technical failure of artificial ascites formation.This retrospective study was approved by the institutional review board. One hundred and thirteen patients underwent percutaneous RFA of hepatic tumours after trying to make artificial ascites using an angiosheath to avoid collateral thermal damage. The technical success rate of making artificial ascites using an angiosheath and conversion rate to other techniques after initial failure of making artificial ascites were evaluated. The technical success rate for RFA was assessed. In addition, potential factors associated with technical failure including previous history of transcatheter arterial chemoembolization (TACE) or RFA, type of abdominal surgery, and adjacent perihepatic structures were reviewed. Predictive factors for the technical failure of artificial ascites formation were analysed using multivariate analysis.The technical success rates of artificial ascites formation by angiosheath and that of RFA were 84.1% (95/113) and 97.3% (110/113), respectively. The conversion rate to other techniques after the failure of artificial ascites formation using an angiosheath was 15.9% (18/113). Previous hepatic resection was the sole independent predictive factor affecting the technical failure of artificial ascites formation (p0.001, odds ratio = 29.03, 95% confidence interval: 4.56-184.69).Making artificial ascites for RFA of hepatic tumours using an angiosheath was technically feasible in most cases. However, history of hepatic resection was a significant predictive factor affecting the technical failure of artificial ascites formation.
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- 2014
295. Single hepatocellular carcinoma ≤ 3 cm in left lateral segment: Liver resection or radiofrequency ablation?
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Joon Hyeok Lee, Jong Man Kim, Hyunchul Rhim, Jae Berm Park, Justin Sangwook Ko, Tae Wook Kang, Choon Hyuck David Kwon, Sung Joo Kim, Seung Woon Paik, and Jae-Won Joh
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Research Report ,Adult ,Male ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Radiofrequency ablation ,medicine.medical_treatment ,Catheter ablation ,Disease-Free Survival ,law.invention ,Resection ,law ,medicine ,Hepatectomy ,Humans ,Aged ,Retrospective Studies ,Aged, 80 and over ,business.industry ,Liver Neoplasms ,Gastroenterology ,Follow up studies ,General Medicine ,Middle Aged ,medicine.disease ,digestive system diseases ,Surgery ,Tumor recurrence ,Hospitalization ,Treatment Outcome ,Hepatocellular carcinoma ,Multivariate Analysis ,Catheter Ablation ,Female ,Lateral segment ,Neoplasm Recurrence, Local ,business ,Nuclear medicine ,Follow-Up Studies - Abstract
To evaluate the long-term results of radiofrequency ablation (RFA) compared to left lateral sectionectomy (LLS) in patients with Child-Pugh class A disease for the treatment of single and small hepatocellular carcinoma (HCC) in the left lateral segments.We retrospectively reviewed the data of 133 patients with single HCC (≤ 3 cm) in their left lateral segments who underwent curative LLS (n = 66) or RFA (n = 67) between 2006 and 2010.The median follow-up period was 33.5 mo in the LLS group and 29 mo in the RFA group (P = 0.060). Most patients had hepatitis B virus-related HCC. The hospital stay was longer in the LLS group than in the RFA group (8 d vs 2 d, P0.001). The 1-, 2-, and 3-year disease-free survival and overall survival rates were 80.0%, 68.2%, and 60.0%, and 95.4%, 92.3%, and 92.3%, respectively, for the LLS group; and 80.8%, 59.9%, and 39.6%, and 98.2%, 92.0%, and 74.4%, respectively, for the RFA group. The disease-free survival curve and overall survival curve were higher in the LLS group than in the RFA group (P = 0.012 and P = 0.013, respectively). Increased PIVKA-II levels and small tumor size were associated with HCC recurrence in multivariate analysis.Liver resection is suitable for single HCC ≤ 3 cm in the left lateral segments.
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- 2014
296. Sound transmission through the human body with digital weaver modulation (DWM) method
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Tae Wook Kang, Jung-Hwan Hwang, Sung-Weon Kang, Sung Eun Kim, and Kyung-Hwan Park
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Amplitude modulation ,Noise ,Engineering ,Analog transmission ,Modulation ,Sound transmission class ,business.industry ,Electronic engineering ,Filter (signal processing) ,Compatible sideband transmission ,business ,Frequency modulation - Abstract
An innovative sound transmission system which transmits sound wirelessly to ears without making any other noise outside is suggested. The system utilizes the human body as a sound transmission medium. The human body is a nonlinear medium and the nonlinear characteristic is the basis of the theorem for the system. When two ultrasonic waves with different frequencies are transmitted into the body, the difference frequency signal between the two original ultrasonic waves is generated during the propagation process and audible to a user. In this paper, single sideband amplitude modulation (SSB AM) method is used as a modulation scheme. SSB AM method can minimize the noise which occurs in the process of generating audible sound. To make a SSB AM modulator with a higher degree of accuracy, digital weaver modulation (DWM) method is adopted. DWM method enables a sharp cutoff filter to be implemented without increasing computational complexity in the DSP. An Equalizer filter which compensates the distortions in the ultrasonic transducer is also designed. The developed system was evaluated with a loaf of beef instead of the human body, and generation of full-bandwidth music sound in the beef was demonstrated. If the proposed system is applied to the human body, sound transmission may be possible without cable line required in conventional earphones.
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- 2014
- Full Text
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297. Perivascular versus nonperivascular small HCC treated with percutaneous RF ablation: retrospective comparison of long-term therapeutic outcomes
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Hyunchul Rhim, Min Woo Lee, Tae Wook Kang, Hyo Keun Lim, Young-Min Kim, and Dongil Choi
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Adult ,Male ,medicine.medical_specialty ,Percutaneous ,Carcinoma, Hepatocellular ,Radiofrequency ablation ,law.invention ,law ,medicine ,Carcinoma ,Humans ,Radiology, Nuclear Medicine and imaging ,Survival rate ,Aged ,Retrospective Studies ,Aged, 80 and over ,business.industry ,Liver Neoplasms ,Retrospective cohort study ,Middle Aged ,medicine.disease ,digestive system diseases ,Survival Rate ,Tumor progression ,Hepatocellular carcinoma ,Catheter Ablation ,Disease Progression ,Female ,Radiology ,Neoplasm Recurrence, Local ,business ,Rf ablation ,Follow-Up Studies - Abstract
To compare the long-term therapeutic outcomes of radiofrequency (RF) ablation for small perivascular hepatocellular carcinoma (HCC) and nonperivascular HCC.This retrospective study was approved by the institutional review board. Between December 2004 and April 2008, 241 patients (175 men and 66 women; age range, 32-82 years) with a single early-stage HCC that was 3 cm or smaller in the greatest dimension underwent ultrasonography-guided percutaneous RF ablation as a first-line treatment. The patients were divided into two groups according to the presence or absence of contacting hepatic vessels that were 3 mm or larger in axial diameter: a group with perivascular HCC (n = 58) and a group with nonperivascular HCC (n = 183). Cumulative local tumor progression, disease-free and long-term survival rates, and prognostic factors were assessed by using Cox proportional hazard models with Bonferroni correction.The overall median follow-up period was 58 months (range, 13-92 months). The cumulative local tumor progression rates were 10%, 16%, and 26% at 1, 3, and 5 years, respectively, in the perivascular group, and 6.7%, 15.5%, and 20.5% in the nonperivascular group; the differences were not significant (P = .323). The corresponding disease-free survival rates were 79%, 41%, and 29% in the perivascular group and 71.3%, 38.7%, and 26.0% in the nonperivascular group, with no significant difference (P = .689). The corresponding overall survival rates were 100%, 94%, and 82% in the perivascular group and 100%, 88.4%, and 73.9% in the nonperivascular group, also without significant difference (P = .267). There was no significant prognostic factor for local tumor progression, whereas extrahepatic and intrahepatic distant recurrences were significant prognostic factors for overall survival in multivariable analysis.The long-term therapeutic outcomes of RF ablation as first-line treatment for small perivascular HCC were similar to those for nonperivascular HCC.
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- 2014
298. Analysis and prevention of cracking during strip casting of AISI 304 stainless steel
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Hee-Kyung Moon, Tae-Wook Kang, Dong-Kyun Choo, and Sunghak Lee
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Materials science ,Metallurgy ,Metals and Alloys ,Surface finish ,engineering.material ,Condensed Matter Physics ,Colada ,Continuous casting ,Cracking ,Mechanics of Materials ,Casting (metalworking) ,Ferrite (iron) ,mental disorders ,engineering ,Wetting ,Composite material ,Austenitic stainless steel - Abstract
In this study, a microstructural investigation was conducted on the cracking phenomenon occurring during strip casting of an AISI 304 stainless steel. Detailed microstructural analyses of the cracked regions showed that most of the cracks were deep, sharp, and parallel to the casting direction. They initiated at the tip of dendrites and propagated along the segregated liquid films between primary dendrites, indicating that they were typical solidification cracks. This cracking phenomenon was closely related to the inhomogeneous solidification of cast strips, represented by depressions, i.e., uneven and somewhat concave areas on the strip surface. The depressions, which were unavoidable in flat rolls due to the presence of a gas gap between the roll and the cast strip, were finely and evenly distributed over the cast strip surface by intentionally providing homogeneous roughness on the roll surface; then, the number and size of cracks were considerably reduced. In addition, the nitrogen gas atmosphere, which retained high solubility in the melt during cooling and good wettability with the roll surface, was successfully used to prevent cracking, because the thickness of the gas gap was minimized.
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- 2001
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299. Effect of biphenyl dimethyl dicarboxylate on the cellular and nonspecific immunosuppressions by ketoconazole in mice
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Tae Wook Kang and Joung Hoon Kim
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Male ,Antifungal Agents ,Erythrocytes ,Time Factors ,Allergic reaction ,Pharmacology toxicology ,chemical and pharmacologic phenomena ,Dioxoles ,Pharmacology ,Drug Hypersensitivity ,Cell activity ,Mice ,Immune system ,Phagocytosis ,Drug Discovery ,Leukocytes ,medicine ,Animals ,Antigens ,Cells, Cultured ,Mice, Inbred ICR ,Sheep ,Chemistry ,Organic Chemistry ,Drug Synergism ,Normal level ,Biphenyl dimethyl-dicarboxylate ,Blood Cell Count ,Killer Cells, Natural ,Ketoconazole ,Immunology ,Molecular Medicine ,Immunization ,Immunosuppressive Agents ,Spleen ,Icr mice ,medicine.drug - Abstract
The effect of biphenyl dimethyl dicarboxylate (PMC) on the cellular and nonspecific immunosuppressions by ketoconazole (KCZ) was investigated in ICR mice. PMC at a dose of 6 mg/kg was administered orally to mice daily for 14 consecutive days. KCZ was suspended in RPMI 1640 medium and orally administered at 160 mg/kg/day 2 hrs after the administration of PMC. Immune responses of the delayed-type hypersensitivity (DTH) reaction to sheep red blood cells (SRBC), phagocytic activity and natural killer (NK) cell activity were evaluated. DTH reaction to SRBC was enhanced to normal level by the combination of PMC and KCZ, compared with treatment of KCZ alone. In the combination of PMC and KCZ, as compared with the treatment of KCZ alone, there were also significant increases in activities of natural killer (NK) cells and phagocytes along with circulating leukocytes. These findings indicate that PMC shows a significant restoration from the immunotoxic status induced by KCZ.
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- 1999
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300. A Distributed Control System Architecture for Strip-Caster Control & Storage Yard Automation
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Jookang Lee, Tae-Wook Kang, Jin S. Lee, and Dukman Lee
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Engineering ,business.industry ,Interface (computing) ,Embedded system ,Programmable logic controller ,Open architecture ,Architecture ,Distributed control system ,business ,Automation ,System bus ,VMEbus - Abstract
This paper presents an open architecture distributed control system using VMEbus based single board processors and PLCs (Programmable Logic Controller) as load-sharing partner. Taking advantage of their own features, we can design more robust and flexible system than those built with VME processors or with PLCs only. Based on this design architecture, the design guidelines about system bus, networking, MMI (Man-Machine Interface), DDC I/O, etc. are proposed to support high speed control and network-throughput required for real applications of POSCO such as strip-casting and thick-plate storage yard automation. These systems are now implemented and show good performance.
- Published
- 1997
- Full Text
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