22 results on '"Kim, Seung Hoon"'
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2. Plasma extraction in a capillary-driven microfluidic device using surfactant-added poly(dimethylsiloxane)
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Kim, Yu Chang, Kim, Seung-Hoon, Kim, Duckjong, Park, Sang-Jin, and Park, Je-Kyun
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- 2010
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3. Impact of changes in housing tenure and affordability status on depressive symptoms: Evidence from a longitudinal study.
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Kim, Seung Hoon, Kim, Hyunkyu, Joo, Hye Jin, Jeong, Sung Hoon, Park, Eun-Cheol, and Jang, Sung-In
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CENTER for Epidemiologic Studies Depression Scale , *MENTAL depression , *NON-communicable diseases , *HOUSING , *PANEL analysis , *HOUSING policy , *PSYCHOLOGICAL tests , *COST analysis , *LONGITUDINAL method - Abstract
Introduction: Housing is an important social determinant of health. We investigated effects of changes in housing tenure and affordability on depressive symptoms.Methods: Data of 9,956 individuals aged >20 years from the Korea Welfare Panel Study (2015-2020) were analyzed. Housing tenure was categorized as homeowners or tenants. Individuals with housing-related expenditures exceeding 30% of household income were defined as having housing unaffordability. Analyses using generalized estimating equations were conducted to evaluate the relationship between changes in housing tenure and affordability on depressive symptoms measured with the Center for Epidemiologic Studies Depression Scale.Results: Individuals who became tenants (β = 0.326, p = 0.027) or were persistent tenants (β = 0.542, p<0.001) demonstrated significantly more severe depressive symptoms than persistent homeowners. Individuals with new (β = 0.562, p < 0.001) or consistent housing unaffordability (β = 1.032, p = 0.036) showed increased depressive symptoms compared with those with persistent housing affordability. Depressive symptoms were reduced in new homeowners and those who left housing unaffordability status (β = -0.807, p = 0.031). The interaction between housing tenure and affordability on depressive symptoms differed by age and household composition. Housing tenure at post-retirement age and single-person households were associated with a decrease in depressive symptoms, respectively.Limitations: All housing-related factors, especially different domains of housing insecurity including unstable neighborhoods or reasons for moving, have not been identified.Conclusions: Changes in housing tenure, affordability, and the two combined were significantly associated with depressive symptoms. Furthermore, the degree of interactive effect varied among age groups and household composition. Housing welfare policies that can stabilize housing tenure and affordability might help prevent depression. [ABSTRACT FROM AUTHOR]- Published
- 2021
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4. C–H⋯X interactions of fluoroform with ammonia, water, hydrogen cyanide, and hydrogen fluoride: conventional and improper hydrogen bonds
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Rhee, Soon Ki, Kim, Seung Hoon, Lee, Sik, and Lee, Jin Yong
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- 2004
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5. Impact of long-term care insurance on medical costs and utilization by patients with Parkinson's disease.
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Kim, Seung Hoon, Park, Eun-Cheol, and Jang, Suk-Yong
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MEDICAL care costs , *MEDICAL care use , *COMPARATIVE studies , *PARKINSON'S disease , *LONG-term care insurance , *DESCRIPTIVE statistics , *TIME series analysis , *DATA analysis software - Abstract
In patients with Parkinson's disease (PD), long-term care insurance (LTCI), which can provide physical activity, might affect medical costs and utilization. We investigated the impact of LTCI on medical costs and utilization among patients with PD aged ≥60 years. Data were derived from the 12-year Korean National Health Insurance Service‒Senior cohort. Among patients with newly developed PD, the intervention group receiving LTCI was matched with the control group using propensity score risk-set matching. As medical costs and utilization may increase markedly immediately before LTCI allocation, the baseline period was set from 5 years to 1 year prior to receiving LTCI. Medical costs and utilization were recorded in six 1-year intervals thereafter. We compared medical costs and utilization between groups using a comparative interrupted time-series analysis. 5011 LTCI beneficiaries and 5011 propensity score- and risk-set-matched controls were included. The overall mean (standard deviation) age was 77.73 (5.7) years, and 66.2% were women, in both groups. LTCI benefit was associated with reduced overall direct medical costs for 5 years (post-intervention year 5: -270$, p = 0.033) , and overall hospital length-of-stay (LOS) for 2 years post-LTCI (post-intervention year 2: -2.43 days, p = 0.002), although medical costs and LOS increased immediately pre-LTCI implementation. The long-term care hospital LOS of LTCI beneficiaries increased relatively by 3-years post-LTCI implementation, particularly in those with a high Charlson Comorbidity Index score (post-intervention year 3: +2.65 days, p = 0.04). LTCI benefit stably decreased medical costs for patients with PD for 5 years, despite the steep increase immediately pre-LTCI benefit, but was limited in reducing medical utilization, particularly as reflected by LOS in long-term care hospitals and patients with comorbidities. LTCI could be a useful health policy to reduce PD disease burden. However, further development is required to provide services that can reduce LOS to PD patients with comorbidities. • In PD patients, just before receiving LTCI, medical costs rose sharply. • Receiving LTCI stably decreased medical costs for patients with PD for 5 years. • In PD patients with comorbidities, LTCI did not effectively lower utilization. • This phenomenon was particularly evident in long-term care hospitals. [ABSTRACT FROM AUTHOR]
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- 2023
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6. Transient Raman spectroscopic studies on the excited-state intramolecular reverse proton transfer in 1-hydroxyanthraquinone
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Cho, Dae Won, Kim, Seung Hoon, Yoon, Minjoong, and Jeoung, Sae Chae
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- 2004
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7. Arthritis status changes and depressive symptoms among middle-aged and older Koreans: Analysis of data from the Korean Longitudinal Study of Aging survey.
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Jeong, Sung Hoon, Kim, Seung Hoon, Park, Minah, Kwon, Junhyun, Lee, Hyeon Ji, and Park, Eun-Cheol
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MENTAL depression , *OLDER people , *COMPETENCY assessment (Law) , *ARTHRITIS , *MIDDLE-aged persons , *AGING , *CENTER for Epidemiologic Studies Depression Scale , *LONGITUDINAL method - Abstract
Objective: Arthritis can negatively affect physical and mental health, especially among middle-aged and older people. This study investigated the longitudinal association between changes in arthritis status and depressive symptoms among Korean adults aged ≥45 years.Methods: We analyzed data from the Korean Longitudinal Study of Aging 2008-2018, using a generalized estimating equation model to investigate associations between arthritis status change and depressive symptoms, which were assessed using five categories according to measurements based on the Center for Epidemiological Studies Depression Scale (CES-D-10).Results: Both men and women whose arthritis status changed to "worse" or remained "same" scored higher for depressive symptoms than those who reported "no symptoms of arthritis" (men, worse = β: 1.07, P ≤ .001, same = β: 0.25 P = .031; women, worse = β: 0.99, P ≤ .001, same = β: 0.13, P = .049). Conversely, men with a "better" arthritis status (β: -0.71, P ≤ .001) and women with a "recovered" arthritis status (β: -0.56, P = .031) scored lower for depressive symptoms than those who reported "no symptoms of arthritis."Conclusions: Arthritis status changes are associated with depressive symptoms in middle-aged and older Koreans. Therefore, mental health evaluation and management interventions are recommended for patients with arthritis and changes in disease status. [ABSTRACT FROM AUTHOR]- Published
- 2021
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8. Hepatic infarction after radiofrequency ablation of hepatocellular carcinoma with an internally cooled electrode.
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Kim, Young-sun, Rhim, Hyunchul, Lim, Hyo K., Choi, Dongil, Lee, Won Jae, and Kim, Seung Hoon
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RADIO frequency ,CARDIOVASCULAR diseases ,HEART diseases ,ELECTRODES - Abstract
Purpose: To elucidate the attributes of hepatic infarction after radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) with an internally cooled electrode.Materials and Methods: The authors retrospectively reviewed follow-up computed tomographic (CT) scans (follow-up period, 1-60.1 months; mean, 15.4 months) in 872 consecutive patients (male:female ratio, 672:200; mean age, 59.5 years) who had undergone 1,120 sessions of RFA for 1,335 HCCs with an internally cooled electrode. Diagnosis of hepatic infarction was made on the basis of CT findings. The authors evaluated the frequency of hepatic infarction, clinical features, initial and follow-up CT findings, accompanied complications, and prognosis. Potential risk factors were evaluated with multiple logistic regression analysis.Results: The frequency of hepatic infarction was 1.8% (20 of 1,120 sessions). Common presenting symptoms were abdominal pain (16 of 20 patients) and fever (11 of 20 patients). All infarctions were found at the first follow-up CT examination. Gas collections were noted in 65% of patients. All lesions showed progressive shrinkage. Accompanied complications were biloma (n = 2), abscess (n = 2), and portal vein thrombosis (n = 1). One patient with a lobar infarction died from hepatic failure. Older age (P = .048) and larger tumor size (P = .026) were statistically significant risk factors by multivariate analysis.Conclusion: RFA complicated by hepatic infarction is uncommon. Although hepatic infarction can be managed conservatively in most cases, possible extensive involvement should be considered seriously because it may cause mortality. [ABSTRACT FROM AUTHOR]- Published
- 2007
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9. High-performance corrosion-resistant fluorine-doped tin oxide as an alternative to carbon support in electrodes for PEM fuel cells.
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Kim, Jong Min, Lee, Yeo Jin, Kim, Seung-hoon, Chae, Keun-Hwa, Yoon, Ki Ro, Lee, Kyung Ah, Byeon, Ayeong, Kang, Yun Sik, Park, Hee-Young, Cho, Min Kyung, Ham, Hyung Chul, and Kim, Jin Young
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The advent of new technologies and growing demand for fuel cell innovation has led to the development of novel non-carbon material strategies with inherent electrical conductance and corrosion resistance. Problems are often observed with carbon-based support materials, due to their limited electrochemical stability. The emphasis is therefore on fabricating high-performance, stable non-carbon alternatives that exhibit advantageous electrochemical properties compared to conventional carbon black, and are thus regarded as ideal electrocatalyst support materials. In this work, we investigated the influence of dopants, and the morphology of conductive, porous doped tin-based oxides, on corrosion resistance and electrical conductivity for fuel cell electrode applications. Among the various doping elements, fluorine anion doping into tin oxide plays a key role in the formation of such structures as a complexing agent for improving electrical conductivity and suppressing electrochemical dissolution processes. When used in polymer electrolyte membrane fuel cells with platinum electrocatalyst loading, fluorine tin oxide nanotubes exhibit not only cell performance comparable to that of state-of-the-art commercial Pt/C, but also excellent cycling stability. The superior electrochemical performance and stability of this novel non-carbon support material is due to its unique features, i.e., excellent electrical conductivity, electrochemical corrosion resistance, and electronic and compressive strain effects due to strong metal-support interactions. Image 1 • The effects of various doping elements on tin oxide (SnO 2) nanotubes (NTs) for PEMFC catalyst support were studied. • Fluorine anion dopant effectively suppressed the electrochemical dissolution of SnO 2. • DFT calculations elucidated the origin of the suppression of electrochemical dissolution of fluorine tin oxide (FTO). • The strong interaction between platinum (Pt) nanoparticles and FTO NTs induced both electronic and lattice strain effects. • The high-performance, corrosion-resistance behavior of Pt/FTO NTs was confirmed by PEMFC operation. [ABSTRACT FROM AUTHOR]
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- 2019
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10. Measuring the differences in work ratios between pediatric and adult ophthalmologic examinations.
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Hyun, Joo, Chang, Jee Ho, Kim, Seung Hoon, Park, Song Hee, and Kim, Sunghoon
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Purpose To assess the differences in work needed for pediatric and adult ophthalmologic examinations. Methods Seven ophthalmology residents conducted slit-lamp and refraction examinations on children 3-7 years of age and adults 20-69 years of age. The examiners reported the magnitude estimate (ME) of their work in relation to two references (cross-reference ME): average adult examination and average pediatric examination. The examination time was also measured. Results For the slit-lamp examination, 50 children and 58 adults were recruited. The ME was 1.45 (95% CI, 1.30-1.62) times higher for the pediatric examinations than for the adult examinations when the reference was an average adult case. With respect to time, the pediatric examinations took 1.22 (95% CI, 1.06-1.41) times longer than the adult examinations. For the refraction examinations, 58 children and 96 adults were recruited. The ME was 1.35 (95% CI, 1.21-1.52) times higher for the pediatric examinations. The pediatric examination took 1.32 (95% CI, 1.16-1.50) times longer than the adult examination. The cross-reference ME ratios measuring the pediatric over adult examinations against both the pediatric and adult reference cases were equivalent in both the slit-lamp and the refraction examinations; however, the ME and time ratios of the pediatric over the adult examinations were not equivalent for the slit-lamp or for the refraction examinations. Conclusions The cross-reference ME showed that pediatric ophthalmologic examinations require more work than the adult examination with validity and reliability. The time estimate was insufficient as a single indicator for work estimation. [ABSTRACT FROM AUTHOR]
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- 2017
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11. Adrenal insufficiency associated with long-term use of inhaled steroid in asthma.
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Choi, Inseon S., Sim, Da-Woon, Kim, Seung-Hoon, and Wui, Jin-Woo
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- 2017
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12. A Scalable QoS-based inter-domain routing scheme in a high speed wide area network
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Kim, Seung-Hoon, Lim, Kyungshik, and Kima, Cheeha
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- 1998
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13. O (log n) numerical algorithms on a mesh with wormhole routing
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Kim, Dongseung and Kim, Seung-Hoon
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- 1994
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14. Efficient stream distribution algorithm for heterogeneous multimedia multicast with link capacity constraint
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Kim, Seung-Hoon, Lim, Kyungshik, and Kim, Cheeha
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- 1997
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15. Association of smartphone use with abnormal social jetlag among adolescents in Korea before and after COVID-19.
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Cho, Yerin, In, Heewon, Park, Minseo, Park, Eun-Cheol, and Kim, Seung Hoon
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TEENAGE girls , *SMARTPHONES , *TEENAGE boys , *TEENAGERS , *COVID-19 - Abstract
• The smartphone usage time was associated with abnormal social jetlag in adolescents. • This association gradually increased as the smartphone usage time increased. • The COVID-19 pandemic significantly strengthened this relationship. • The association was prominent in female adolescents. This study aimed to use social jetlag to determine how smartphone overuse by adolescents before and after the COVID-19 pandemic might be associated with their circadian rhythm. We used 2017 and 2020 Korea Youth Risk Behavior web-based Survey data and conducted a survey analysis on 100,976 adolescents. The dependent variable was abnormal social jetlag. Based on the times recorded by the survey, we calculated the weekday midpoint and weekend sleep time. The main independent variable was smartphone usage time (<2h/day, 2–3.9 h/day, 4–5.9 h/day, and ≥ 6 h/day). Multiple logistic regression and relative excess risk due to interaction (RERI) were performed. Abnormal social jetlag was most prevalent in male and female adolescents who used smartphones ≥ 6 h/day (adjusted odds ratio [AOR] = 2.60, 95 % confidence interval [CI] = 2.47–2.74). The longer the smartphone usage time, the higher the association with abnormal social jetlag. This association was more prominent in female adolescents. The additive interaction between longer smartphone usage time and post-COVID-19 year was statistically significant (total: RERI = 0.92, 95 % CI = 0.90–0.95; males: RERI = 0.83, 95 % CI = 0.80–0.87; females: RERI = 1.13, 95 % CI = 1.08–1.18). Our results clearly indicated that increased smartphone usage time tended to result in greater social jetlag, an association that was more pronounced in female. Moreover, the COVID-19 pandemic significantly strengthened this relationship. Further research is needed regarding the proper use of smartphones to ensure good sleep-in adolescents after the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]
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- 2023
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16. Leaching kinetics of lanthanum in sulfuric acid from rare earth element (REE) slag.
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Kim, Chul-Joo, Yoon, Ho-Sung, Chung, Kyung Woo, Lee, Jin-Young, Kim, Sung-Don, Shin, Shun Myung, Lee, Su-Jeong, Joe, A-Ram, Lee, Se-Il, Yoo, Seung-Joon, and Kim, Seung-Hoon
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LEACHING , *LANTHANUM , *SULFURIC acid , *RARE earth metals , *MONAZITE , *MAGNETITE - Abstract
Abstract: REE slag was obtained from reduction smelting of magnetite ore containing monazite. Using the REE slag, the leaching kinetics of lanthanum from the slag was studied under the conditions of slurry density of 1.5g slag per L of 0.3M H2SO4, agitation of 750rpm and temperature ranging from 30 to 80°C. After five hours of leaching, the lanthanum was completely leached from the slag. Leaching kinetics can be described by the shrinking core model for spherical particles of unchanging size and leaching was found to occur in two stages. The initial leaching rate was controlled by chemical reaction. Using the Arrhenius equation, the apparent activation energy of the chemical reaction rate controlling step was determined to be 10.0kJmol−1. As leaching of the lanthanum increased, the reaction rate was controlled by diffusion through an ash layer. The apparent activation energy of the second stage was determined to be 24.8kJmol−1. The leaching rate and extent of leaching of lanthanum from the slag increased with an increase in leaching temperature. [Copyright &y& Elsevier]
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- 2014
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17. Detection of rectal cancer and response to concurrent chemoradiotherapy by proton magnetic resonance spectroscopy
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Kim, Min Ju, Lee, Soon Jin, Lee, Jung Hee, Kim, Seung Hoon, Chun, Ho Kyung, Kim, Seong Hyun, Lim, Hyo Keun, and Yun, Seong Hyeon
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RECTAL cancer treatment , *CANCER chemotherapy , *CANCER radiotherapy , *PROTON magnetic resonance spectroscopy , *PATIENT monitoring , *NONINVASIVE diagnostic tests - Abstract
Abstract: Introduction: To diagnose rectal cancer and monitor treatment response after preoperative concurrent chemoradiotherapy (CCRT) in rectal cancer patients using proton-1 magnetic resonance spectroscopy (1H-MRS). Materials and Methods: We enrolled 134 rectal cancer patients before treatment, of whom 34 underwent preoperative CCRT and follow-up MR spectroscopy before surgery. 1H-MRS was performed using a six-channel phased-array coil at 3.0 T. We evaluated the presence of a choline peak at 3.2 ppm, and lipid peaks at 0.9 and 1.3 ppm, and glutamine and glutamate peaks at 2.1-2.3 and 2.7 ppm seen at two TEs (40 and 135 ms). We divided MR spectra patterns into two groups (A and B). Results: A choline peak at 3.2 ppm seen in both TEs was characteristic for rectal cancer before treatment. Of 103 patients, 55 (53%) showed an elevated choline peak before treatment (type A). Type A spectra were seen in 68% of patients (23/34) before preoperative CCRT. After CCRT, the choline peak disappeared, resulting in only the lipid peak at 1.3 ppm (type B) in 97% of patients (33/34). Discussion: We optimized a localized in vivo 1H-MRS method for detection of rectal adenocarcinoma and monitoring treatment response after preoperative CCRT. The method appears to be a promising and feasible noninvasive modality. [Copyright &y& Elsevier]
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- 2012
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18. Radiofrequency ablation of the liver abutting stomach: In vivo comparison of gastric injury before and after intragastric saline administration in a porcine model
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Lee, Jongmee, Lim, Hyo K., Choi, Dongil, Kim, Seung Hoon, Min, Kwangseon, and Jeon, Yong Hwan
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STOMACH injuries , *WOUND care , *RADIO frequency , *SALINE solutions , *LABORATORY swine , *LIVER tumors , *HISTOPATHOLOGY - Abstract
Abstract: Purpose: To compare the in vivo gastric injury observed during radiofrequency (RF) ablation of the liver abutting the stomach before and after the intragastric administration of chilled saline. Materials and methods: Twenty RF ablation zones were created in the livers of 10 pigs with a 1-cm-exposed active tip of an internally cooled electrode under ultrasound guidance for 10min. Ten RF ablation zones were created before (non-saline group) and after (saline group) the intragastric administration of approximately 1000mL of chilled saline, and 20 RF ablation zones were made in the posterior part of the left lobe abutting the stomach. The frequency and severity of the thermal injury observed in the stomach of the two groups were compared histologically. Results: All the resected gastric specimens showed thermal injuries of varying degrees of severity. The largest diameter of the gastric injury was significantly smaller in the saline group (mean 1.5cm; range 1.3–1.8cm) than in the non-saline group (mean 2.1cm; range 1.8–2.4cm) (p =0.000). The saline group showed significantly less thermal injury to the muscular layer of the gastric wall by the histopathology (p =0.033). Conclusions: The intragastric administration of chilled saline might be a useful technique for reducing the severity of gastric injury during RF ablation of the liver abutting the stomach. [Copyright &y& Elsevier]
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- 2009
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19. Changes in signal-to-noise ratios and contrast-to-noise ratios of hypervascular hepatocellular carcinomas on ferucarbotran-enhanced dynamic MR imaging
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Park, Yulri, Choi, Dongil, Kim, Seong Hyun, Kim, Seung Hoon, Kim, Min Ju, Lee, Jongmee, Lim, Jae Hoon, Lee, Won Jae, and Lim, Hyo K.
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LIVER cancer , *SIGNAL-to-noise ratio , *MAGNETIC resonance imaging , *TUMORS , *COMPARATIVE studies , *DEXTRAN , *HEPATOCELLULAR carcinoma , *DIGITAL image processing , *INTRAVENOUS injections , *IRON , *IRON compounds , *LIVER tumors , *RESEARCH methodology , *MEDICAL cooperation , *OXIDES , *RESEARCH , *EVALUATION research , *CONTRAST media , *PATHOLOGIC neovascularization , *DRUG administration , *DRUG dosage - Abstract
Purpose: To verify changes in the signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of hypervascular hepatocellular carcinomas (HCCs) on ferucarbotran-enhanced dynamic T1-weighted MR imaging.Materials and Methods: Fifty-two patients with 61 hypervascular HCCs underwent ferucarbotran-enhanced dynamic MR imaging, and then hepatic resection. Hypervascular HCCs were identified when definite enhancement was noted during the arterial dominant phase of three-phase MDCT. Dynamic MR Images with T1-weighted fast multiplanar spoiled gradient-recalled echo sequence (TR200/TE4.2) were obtained before and 20 s, and 1, 3, 5, and 10 min, after bolus injection of ferucarbotran. We estimated the signal intensities of tumors and livers, and calculated the SNRs and CNRs of the tumors.Results: On ferucarbotran-enhanced dynamic MR imaging, SNR measurements showed a fluctuating pattern, namely, an increase in SNR followed by a decrease and a subsequent increase (or a decrease in SNR followed by a increase and a subsequent decrease) in 50 (82.0%) of 61 tumors, a single-peak SNR pattern (highest SNR on 20 s, 1, 3, or 5 min delayed images followed by a decrease) in seven (11.5%), and a decrease in SNR followed by an increase in four (6.6%). Maximum absolute CNRs with positive value were noted on 10 min delayed images in 41 (67.2%) tumors, and maximum absolute CNRs with negative value were observed on 20 s delayed images in 12 (19.7%) and on 1 min delayed images in eight (13.1%).Conclusion: Despite showing various SNR and CNR changes, the majority of hypervascular HCCs demonstrated a fluctuating SNR pattern on ferucarbotran-enhanced dynamic MR imaging and a highest CNR on 10 min delayed image, which differed from the classic enhancement pattern on multiphasic CT. [ABSTRACT FROM AUTHOR]- Published
- 2006
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20. Detection of hepatic VX2 carcinomas with ferucarbotran-enhanced magnetic resonance imaging in rabbits: Comparison of nine pulse sequences
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Kim, Seong Hyun, Choi, Dongil, Lim, Hyo K., Kim, Min Ju, Jang, Kyung Mi, Kim, Seung Hoon, Lee, Won Jae, Lee, Jongmee, Jeon, Yong Hwan, and Lim, Jae Hoon
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LIVER cancer , *MAGNETIC resonance imaging , *LABORATORY rabbits , *QUALITATIVE research , *ANIMAL experimentation , *COMPARATIVE studies , *DEXTRAN , *DIGITAL image processing , *IRON , *IRON compounds , *LIVER tumors , *RESEARCH methodology , *MEDICAL cooperation , *NONPARAMETRIC statistics , *OXIDES , *RABBITS , *RESEARCH , *PILOT projects , *EVALUATION research , *CONTRAST media , *RECEIVER operating characteristic curves , *MEDICAL artifacts - Abstract
Abstract: Objective: To compare the diagnostic performance of a variety of magnetic resonance imaging (MRI) sequences, in order to identify the most effective ferucarbotran-enhanced sequence for the detection of multiple small hepatic VX2 carcinomas in rabbits. Methods: Fifteen rabbits with experimentally induced 135 VX2 carcinomas in the liver underwent ferucarbotran-enhanced MRI using the following nine pulse sequences: a fat-suppressed fast spin-echo (FSE) sequence with two echo times (TE) (proton density- and T2-weighted images), four different T2*-weighted fast multiplanar GRASS (gradient-recalled acquisition in the steady state) (FMPGR) with the combination of three TEs (9, 12, 15ms, respectively) and two flip angles (20°, 80°, respectively), T2*-weighted fast multiplanar spoiled GRASS (FMPSPGR), T1-weighted FMPSPGR, and dynamic T1-weighted FMPSPGR. All images were reviewed by three radiologists with quantitative and qualitative analysis. Results: Tumor-to-liver contrast-to-noise ratio of the proton density-weighted FSE sequence was significantly higher than those of the others (p <0.05). The lesion conspicuities of proton density- and T2-weighted FSE and T2*-weighted FMPGR (TE/flip angle, 9/20° and 12/20°) images were better and the image artifacts of T2*-weighted FMPGR (TE/flip angle, 15/20° and 12/80°) and T2*-weighted FMPSPGR images were more prominent than those of the others (p <0.05). The lesion detection in T2- and proton density-weighted FSE and T2*-weighted FMPGR (TE/flip angle, 12/20°) images were superior to those of the others and for the detection of very small hepatic tumors of less than 5mm, the sensitivities of these sequences were less than 30%. Conclusion: Ferucarbotran-enhanced T2- and proton density-weighted FSE and T2*-weighed FMPGR (TE/flip angle, 12/20°) images were found to be the most effective pulse sequences for the detection of multiple small hepatic VX2 carcinomas but these sequences were limited in the detection of very small hepatic tumors of less than 5mm in size. [Copyright &y& Elsevier]
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- 2006
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21. Therapeutic response assessment of percutaneous radiofrequency ablation for hepatocellular carcinoma: Utility of contrast-enhanced agent detection imaging
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Kim, Chan Kyo, Choi, Dongil, Lim, Hyo K., Kim, Seung Hoon, Lee, Won Jae, Kim, Min Ju, Lee, Ji Yeon, Jeon, Yong Hwan, Lee, Jongmee, Lee, Soon Jin, and Lim, Jae Hoon
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TUMORS , *CANCER patients , *CYSTS (Pathology) , *ONCOLOGY - Abstract
Purpose: To assess the utility of contrast-enhanced agent detection imaging (ADI) in the assessment of the therapeutic response to percutaneous radiofrequency (RF) ablation in patients with hepatocellular carcinoma (HCC).Materials and Methods: Ninety patients with a total of 97 nodular HCCs (mean, 2.1+/-1.3 cm; range, 1.0-5.0 cm) treated with percutaneous RF ablation under the ultrasound guidance were evaluated with contrast-enhanced ADI after receiving an intravenous bolus injection of a microbubble contrast agent (SH U 508A). We obtained serial contrast-enhanced ADI images during the time period from 15 to 90 s after the initiation of the bolus contrast injection. All of the patients underwent a follow-up four-phase helical CT at 1 month after RF ablation, which was then repeated at 2-4 month intervals during a period of at least 12 months. The results of the contrast-enhanced ADI were compared with those of the follow-up CT in terms of the presence or absence of residual unablated tumor and local tumor progression in the treated lesions.Results: On contrast-enhanced ADI, technical success was obtained in 94 (97%) of the 97 HCCs, while residual unablated tumors were found in three HCCs (3%). Two of the three tumors that were suspicious (was not proven) for incomplete ablation were subjected to additional RF ablation. The remaining one enhancing lesion that was suspicious of a residual tumor on contrast-enhanced ADI was revealed to be reactive hyperemia at the 1-month follow-up CT. Therefore; the diagnostic concordance between the contrast-enhanced ADI and 1-month follow-up CT was 99%. Of the 94 ablated HCCs without residual tumors on both the contrast-enhanced ADI and 1-month follow-up CT after the initial RF ablation, five (5%) had CT findings of local tumor progression at a subsequent follow-up CT.Conclusion: Despite its limitations in predicting local tumor progression in the treated tumors, contrast-enhanced ADI is potentially useful for evaluating the early therapeutic effect of percutaneous RF ablation for HCCs. [ABSTRACT FROM AUTHOR]- Published
- 2005
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22. Antinociceptive effects of nefopam modulating serotonergic, adrenergic, and glutamatergic neurotransmission in the spinal cord.
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Chae, Joo Wung, Kang, Dong Ho, Li, Yaqun, Kim, Seung Hoon, Lee, Hyung Gon, Choi, Jeong Il, Yoon, Myung Ha, and Kim, Woong Mo
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SPINAL cord , *ADRENERGIC receptors , *NEURAL transmission , *EXCITATORY amino acid antagonists , *GLUTAMATE receptors - Abstract
• Intrathecal nefopam effectively attenuated formalin-induced pain behavior. • Intrathecal nefopam inhibited the reuptake of 5-HT and NE and reduced glutamate release after formalin injection. • The blockade of serotonergic, adrenergic, or group III metabotropic glutamate receptors partially reversed the analgesic effects of nefopam. The present study investigated the effects of intrathecal nefopam on the pain behavior and on the extracellular levels of serotonin (5-HT), norepinephrine (NE), and glutamate in the spinal cord, in a rat model of pain induced by formalin. Nefopam was intrathecally administered 10 min prior to the formalin test to assess its antinociceptive effects. In another cohorts of animals, dihydroergocristine, yohimbine, or (RS)-α-Methylserine-O-phosphate (MSOP), a serotonergic, α-2 adrenergic receptor, or group III metabotropic glutamate receptor antagonist, respectively, were administered prior to the application of nefopam in the formalin test. Microdialysis studies were conducted to measure the extracellular levels of 5-HT, NE, and glutamate in the spinal cord following nefopam administration. Intrathecal nefopam reduced formalin-induced behavior in both phases of the test. The blockade of serotonergic or adrenergic receptors partially reversed the analgesic effects of nefopam in the first phase of the formalin test whereas MSOP reversed these effects in both phases. The microdialysis results revealed that intrathecal nefopam significantly increased 5-HT and NE levels and attenuated the formalin-induced release of glutamate in the spinal cord. Thus, the present data suggest that the increase in the extracellular levels of 5-HT and NE, and reductions in glutamate release in the spinal cord, may have contributed to the analgesic effects of nefopam. [ABSTRACT FROM AUTHOR]
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- 2020
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