1.Brain Tumor Classification by Methylation Profile
Jin Woo PARK ; Kwanghoon LEE ; Eric Eunshik KIM ; Seong-Ik KIM ; Sung-Hye PARK
Journal of Korean Medical Science 2023;38(43):e356-
The goal of the methylation classifier in brain tumor classification is to accurately classify tumors based on their methylation profiles. Accurate brain tumor diagnosis is the first step for healthcare professionals to predict tumor prognosis and establish personalized treatment plans for patients. The methylation classifier can be used to perform classification on tumor samples with diagnostic difficulties due to ambiguous histology or mismatch between histopathology and molecular signatures, i.e., not otherwise specified (NOS) cases or not elsewhere classified (NEC) cases, aiding in pathological decision-making. Here, the authors elucidate upon the application of a methylation classifier as a tool to mitigate the inherent complexities associated with the pathological evaluation of brain tumors, even when pathologists are experts in histopathological diagnosis and have access to enough molecular genetic information. Also, it should be emphasized that methylome cannot classify all types of brain tumors, and it often produces erroneous matches even with high matching scores, so, excessive trust is prohibited. The primary issue is the considerable difficulty in obtaining reference data regarding the methylation profile of each type of brain tumor. This challenge is further amplified when dealing with recently identified novel types or subtypes of brain tumors, as such data are not readily accessible through open databases or authors of publications. An additional obstacle arises from the fact that methylation classifiers are primarily research-based, leading to the unavailability of charging patients. It is important to note that the application of methylation classifiers may require specialized laboratory techniques and expertise in DNA methylation analysis.
2.Differences in Perspectives of Medical Device Adverse Events: Observational Results in Training Program Using Virtual Cases
Chiho YOON ; Ki Chang NAM ; You Kyoung LEE ; Youngjoon KANG ; Soo Jeong CHOI ; Hye Mi SHIN ; HyeJung JANG ; Jin Kuk KIM ; Bum Sun KWON ; Hiroshi ISHIKAWA ; Eric WOO
Journal of Korean Medical Science 2019;34(39):e255-
BACKGROUND: Medical device adverse event reporting is an essential activity for mitigating device-related risks. Reporting of adverse events can be done by anyone like healthcare workers, patients, and others. However, for an individual to determine the reporting, he or she should recognize the current situation as an adverse event. The objective of this report is to share observed individual differences in the perception of a medical device adverse event, which may affect the judgment and the reporting of adverse events. METHODS: We trained twenty-three participants from twelve Asia-Pacific Economic Cooperation (APEC) member economies about international guidelines for medical device vigilance. We developed and used six virtual cases and six questions. We divided participants into six groups and compared their opinions. We also surveyed the country's opinion to investigate the beginning point of ‘patient use’. The phases of ‘patient use’ are divided into: 1) inspecting, 2) preparing, and 3) applying medical device. RESULTS: As for the question on the beginning point of ‘patient use,’ 28.6%, 35.7%, and 35.7% of participants provided answers regarding the first, second, and third phases, respectively. In training for applying international guidelines to virtual cases, only one of the six questions reached a consensus between the two groups in all six virtual cases. For the other five questions, different judgments were given in at least two groups. CONCLUSION: From training courses using virtual cases, we found that there was no consensus on ‘patient use’ point of view of medical devices. There was a significant difference in applying definitions of adverse events written in guidelines regarding the medical device associated incidents. Our results point out that international harmonization effort is needed not only to harmonize differences in regulations between countries but also to overcome diversity in perspectives existing at the site of medical device use.
Consensus
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Delivery of Health Care
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Education
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Humans
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Individuality
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Judgment
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Social Control, Formal
3.Host modulation therapy for improving the osseointegration of dental implants under bone healing-suppressed conditions: a preclinical rodent-model experiment
Young Woo SONG ; Jin-Young PARK ; Yoon-Hee KWON ; Wooyoung Eric JANG ; Sung-JinSung-Jin KIMKIM ; Jeong Taeg SEO ; Seok Jun MOON ; Ui-Won JUNG
Journal of Periodontal & Implant Science 2024;54(3):177-188
Purpose:
Placing dental implants in areas with low bone density or in conditions where bone healing is suppressed is challenging for clinicians. An experiment using a rodent model was performed with the aim of determining the efficacy of host modulation by increasing the systemic level of cholesterol sulfate (CS) using Irosustat in the context of the bone healing process around dental implants.
Methods:
In 16 ovariectomised female Sprague-Dawley rats, 2 implant fixtures were placed in the tibial bones (1 fixture on each side). At 1 week after surgery, the high-CS group (n=8) received Irosustat-mixed feed, while the control group (n=8) was fed conventionally. Block specimens were obtained at 5 weeks post-surgery for histologic analysis and the data were evaluated statistically (P<0.05).
Results:
Unlike the high-CS group, half of the specimens in the control group demonstrated severe bone resorption along with a periosteal reaction in the cortex. The mean percentages of bone-to-implant contact (21.5%) and bone density (28.1%) near the implant surface were significantly higher in the high-CS group than in the control group (P<0.05), as was the number of Haversian canals (by 5.3).
Conclusions
Host modulation by increasing the CS level may enhance the osseointegration of dental implants placed under conditions of impaired bone healing.
4.Host modulation therapy for improving the osseointegration of dental implants under bone healing-suppressed conditions: a preclinical rodent-model experiment
Young Woo SONG ; Jin-Young PARK ; Yoon-Hee KWON ; Wooyoung Eric JANG ; Sung-JinSung-Jin KIMKIM ; Jeong Taeg SEO ; Seok Jun MOON ; Ui-Won JUNG
Journal of Periodontal & Implant Science 2024;54(3):177-188
Purpose:
Placing dental implants in areas with low bone density or in conditions where bone healing is suppressed is challenging for clinicians. An experiment using a rodent model was performed with the aim of determining the efficacy of host modulation by increasing the systemic level of cholesterol sulfate (CS) using Irosustat in the context of the bone healing process around dental implants.
Methods:
In 16 ovariectomised female Sprague-Dawley rats, 2 implant fixtures were placed in the tibial bones (1 fixture on each side). At 1 week after surgery, the high-CS group (n=8) received Irosustat-mixed feed, while the control group (n=8) was fed conventionally. Block specimens were obtained at 5 weeks post-surgery for histologic analysis and the data were evaluated statistically (P<0.05).
Results:
Unlike the high-CS group, half of the specimens in the control group demonstrated severe bone resorption along with a periosteal reaction in the cortex. The mean percentages of bone-to-implant contact (21.5%) and bone density (28.1%) near the implant surface were significantly higher in the high-CS group than in the control group (P<0.05), as was the number of Haversian canals (by 5.3).
Conclusions
Host modulation by increasing the CS level may enhance the osseointegration of dental implants placed under conditions of impaired bone healing.
5.Host modulation therapy for improving the osseointegration of dental implants under bone healing-suppressed conditions: a preclinical rodent-model experiment
Young Woo SONG ; Jin-Young PARK ; Yoon-Hee KWON ; Wooyoung Eric JANG ; Sung-JinSung-Jin KIMKIM ; Jeong Taeg SEO ; Seok Jun MOON ; Ui-Won JUNG
Journal of Periodontal & Implant Science 2024;54(3):177-188
Purpose:
Placing dental implants in areas with low bone density or in conditions where bone healing is suppressed is challenging for clinicians. An experiment using a rodent model was performed with the aim of determining the efficacy of host modulation by increasing the systemic level of cholesterol sulfate (CS) using Irosustat in the context of the bone healing process around dental implants.
Methods:
In 16 ovariectomised female Sprague-Dawley rats, 2 implant fixtures were placed in the tibial bones (1 fixture on each side). At 1 week after surgery, the high-CS group (n=8) received Irosustat-mixed feed, while the control group (n=8) was fed conventionally. Block specimens were obtained at 5 weeks post-surgery for histologic analysis and the data were evaluated statistically (P<0.05).
Results:
Unlike the high-CS group, half of the specimens in the control group demonstrated severe bone resorption along with a periosteal reaction in the cortex. The mean percentages of bone-to-implant contact (21.5%) and bone density (28.1%) near the implant surface were significantly higher in the high-CS group than in the control group (P<0.05), as was the number of Haversian canals (by 5.3).
Conclusions
Host modulation by increasing the CS level may enhance the osseointegration of dental implants placed under conditions of impaired bone healing.
6.The study for the roles of intratracheally administered histamine in the neutrophil-mediated acute lung injury in rats:.
Younsuck KOH ; Brooks M HYBERTSON ; Eric K JEPSON ; Mi Jung KIM ; In Chul LEE ; Chae Man LIM ; Sang Do LEE ; Woo Sung KIM ; Dong Soon KIM ; Won Dong KIM ; John E REPINE
Tuberculosis and Respiratory Diseases 1996;43(3):308-322
BACKGROUND: Neutrophils are considered to play critical roles in the development of acute respiratory distress syndrome. Histamine, which is distributed abundantly in lung tissue, increases the rolling of neutrophills via increase of P-selectin expression on the surface of endothelial cells and is known to have some interrelationships with IL-1, IL-8 and TNF-alpha. We studied to investigate the effect of the histamine on the acute lung injury of the rats induced by intratracheal insufflation of TNF-alpha which has less potency to cause lung injury compared to IL-1 in rats. METHODS: We intratracheally instilled saline or TNF(R&D, 500ng), IL-1(R&D, 50ng)or histamine of varius dose(1.1, 11 and 55 microg/kg) with and without TNF separately in Sprague-Dawley rats weighing 270-370 grams. We also intratracheally treated IL-l(50ng) along with histamine(55 microg/kg). In cases, there were synergistic effects induced by histamine on the parameters of TNF-induced acute lung injury, antihistainmes(Sigma, mepyramine as a H1 receptor blockade and ranitidine as a H2 receptor blockade, 10 mg/kg in each)were co-administered intravenously to the rats treated TNF along with histamine(1.1 microg/kg) intratracheally. Then after 5 h we measured lung lavage neutrophil numbers, lavage cytokine-induced neutrophil chemoatt- ractants(CINC), lung myeloperoxidase activity(MPO) and lung leak. We also intratracheally insufflated TNF with/without histamine(11 microg/kg), then after 24 h measured lung leak in rats. Statistical analyses were done by Kruskal-Wallis nonparametric ANOVA test with Dunn's multiple comparison test or by Mann-Whitney U test. RESULTS: We found that rats given TNF, histamine alone(11 and 55 microg/kg), and TNF with histamine(1.1, 11, and 55 microg/kg) intratracheally had increased (P<0.05) lung MPO activity compared with saline-treated control rats. TNF with histamine 11 microg/kg had increased MPO activity (P=0.0251) compared with TNF-treated rats. TNF and TNF with histamine(l.l, 11,, and 55 microg/kg) intratracheally had all increased (P<0.05) lung leak, lavage neutophil numbers and lavage CINC activities compared with saline. TNF with histamine 1.1 microg/kg had increased (P=0.0367) lavage neutrophil numbers compared with TNF treated rats. But there were no additive effect of histamine with TNF compared with TNF alone in acute lung leak on 5 h and 24 h in rats. Treatment of rats with the H1 and H2 antagonists resulted in inhibitions of lavage neutrophil accumulations and lavage CINC activity elevations elicited by co-treated histamine in TNF-induced acute lung injury intratracheally in rats. We also found that rats given IL-1 along with histamine intratracheally did not have increase in lung leak compared with IL-1 treated rats. CONCLUSION: Histamine administered intratracheally did not have synergistic effects on TNF-induced acute lung leak inspite of additive effects on increase in MPO activity and lavage neutrophil numbers in rats. These observations suggest that instilling histamine intratracheally would not play synergistic roles in neutrophil-mediated acute lung injury in rats.
Acute Lung Injury*
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Animals
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Bronchoalveolar Lavage
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Endothelial Cells
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Histamine*
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Insufflation
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Interleukin-1
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Interleukin-8
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Lung
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Lung Injury
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Neutrophils
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P-Selectin
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Peroxidase
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Pyrilamine
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Ranitidine
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Rats*
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Rats, Sprague-Dawley
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Respiratory Distress Syndrome, Adult
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Therapeutic Irrigation
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Tumor Necrosis Factor-alpha
7.Efficacy and Safety of Glecaprevir/Pibrentasvir in Korean Patients with Chronic Hepatitis C: A Pooled Analysis of Five Phase II/III Trials
Jeong HEO ; Yoon Jun KIM ; Jin-Woo LEE ; Ji Hoon KIM ; Young-Suk LIM ; Kwang-Hyub HAN ; Sook-Hyang JEONG ; Mong CHO ; Ki Tae YOON ; Si Hyun BAE ; Eric D. CROWN ; Linda M. FREDRICK ; Negar Niki ALAMI ; Armen ASATRYAN ; Do Hyun KIM ; Seung Woon PAIK ; Youn-Jae LEE
Gut and Liver 2021;15(6):895-903
Background/Aims:
Glecaprevir/pibrentasvir (G/P) is the first pan-genotypic direct-acting antiviral combination therapy approved in Korea. An integrated analysis of five phase II and III trials was conducted to evaluate the efficacy and safety of G/P in Korean patients with chronic hepatitis C virus (HCV) infection.
Methods:
The study analyzed pooled data on Korean patients with HCV infection enrolled in the ENDURANCE 1 and 2, SURVEYOR II part 4 and VOYAGE I and II trials, which evaluated the efficacy and safety of 8 or 12 weeks of G/P treatment. The patients were either treatment-naïve or had received sofosbuvir or interferon-based treatment. Efficacy was evaluated by assessing the rate of sustained virologic response at 12 weeks posttreatment (SVR12). Safety was evaluated by monitoring adverse events (AEs) and laboratory assessments.
Results:
The analysis included 265 patients; 179 (67.5%) were HCV treatment-naïve, and most patients were either subgenotype 1B (48.7%) or 2A (44.5%). In the intention-to-treat population, 262 patients (98.9%) achieved SVR12. Three patients did not achieve SVR12: one had virologic failure and two had non-virologic failures. Most AEs were grade 1/2; eight patients (3.0%) expe-rienced at least one grade ≥3 AE. No serious AEs related to G/P treatment were reported, and grade ≥3 hepatic laboratory abnormalities were rare (0.8%).
Conclusions
G/P therapy was highly efficacious and well tolerated in Korean patients with HCV infection, with most patients achieving SVR12. The safety profile was comparable to that observed in a pooled analysis of a global pan-genotypic population of patients with HCV infection who received G/P.