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Baek JH, Lee H, Myung W, Kim H, Choi YH, Kim DK, Hong KS, Choi H. The association between inflammatory markers and general psychological distress symptoms. Gen Hosp Psychiatry 2019; 56:9-12. [PMID: 30476675 DOI: 10.1016/j.genhosppsych.2018.11.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Revised: 11/11/2018] [Accepted: 11/15/2018] [Indexed: 01/08/2023]
Abstract
OBJECTIVE This study explored the association between low-grade inflammation measured using multiple common inflammatory markers and general psychological distress symptoms. METHOD A total of 68,463 Korean adults were included. White blood cell counts with differential count, fibrinogen, C-reactive protein (CRP), ferritin and rheumatoid factor were measured. General psychological distress symptoms were assessed using 18 questions of psychosocial well-being index short form (PWI-SF). RESULTS Among the eight inflammatory markers measured, WBC count, segmented neutrophil count, monocyte and CRP level were significantly and independently associated with broad psychological symptoms. In contrast, fibrinogen and ferritin showed a weak association with limited number of items. No significant association was detected with lymphocyte and RF. CONCLUSION General psychological distress symptoms were associated with multiple inflammatory markers in Korean adults. The association patterns differed by the types of inflammatory markers. Additional investigation into the relationship between general inflammatory markers and diverse psychological distress symptoms is warranted.
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Pyo JH, Lee H, Min YW, Min BH, Lee JH, Kim KM, Yoo H, Kim K, Choi YH, Kim JJ, Kim S. Effect of age on the clinical outcomes of patients with early gastric cancer with undifferentiated-type histology. Surgery 2018; 165:802-807. [PMID: 30551867 DOI: 10.1016/j.surg.2018.11.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 11/05/2018] [Accepted: 11/05/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND Undifferentiated-type early gastric cancers account for a large proportion of gastric cancers in younger patients. Therefore, the clinical outcomes of endoscopic resection in younger patients are a major concern. We aimed to investigate the influence of age on lymph node metastasis and long-term survival after surgery for undifferentiated-type early gastric cancers. METHODS We identified 4,236 patients who underwent surgery for undifferentiated-type early gastric cancers. For each T stage, the correlation between age and lymph node metastasis was analyzed using a multivariate logistic regression. Lymph node metastasis rates were compared between younger (<40 years) and older patients (≥40 years) who fulfilled the expanded criteria for endoscopic resection. The Kaplan-Meier method was used to compare long-term survival between younger and older patients. RESULTS Younger age groups (20-29 and 30-39 years) had the highest lymph node metastasis rate within each T stage (5.7% and 5.7% for T1a, 26.3% and 24.1% for T1b, respectively). After adjusting for possible covariates, however, age did not have a significant effect on lymph node metastasis in either T stage (P = .127 for T1a, P = .114 for T1b). Among patients fulfilling the expanded indication for endoscopic resection, younger patients had a slightly higher lymph node metastasis rate compared with older patients (2.7% versus 2.0%), although this difference was not statistically significant. Although younger patients had a significantly better overall survival (P < .001), no significant age-related differences were observed in recurrence-free and disease-specific survival (P = .051 and P = .069) CONCLUSION: Endoscopic resection may be feasible in young patients with undifferentiated-type early gastric cancers because these patients share a similar lymph node metastasis rate and long-term survival outcomes with older patients.
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Park I, Choi JH, Kim EK, Kim SM, Yang JH, Song YB, Hahn JY, Choi SH, Gwon HC, Lee SH, Choi YH, Oh JK. P1790Non-invasive identification of coronary collateral vessels by coronary computed tomography. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy565.p1790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Pyo JH, Lee H, Min YW, Min BH, Lee JH, Kim KM, Yoo H, Kim K, Choi YH, Kim JJ, Kim S. Young Age and Risk of Lymph Node Metastasis in Differentiated Type Early Gastric Cancer. Ann Surg Oncol 2018; 25:2713-2719. [PMID: 30006689 DOI: 10.1245/s10434-018-6659-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Indexed: 01/23/2023]
Abstract
BACKGROUND Young patients with gastric cancer reportedly have a worse prognosis than older patients due to delayed diagnosis and more aggressive tumor behavior. However, it is unclear whether this applies to early gastric cancer (EGC), for which endoscopic resection is indicated. We investigated the association between age and lymph node metastasis (LNM). METHODS We identified 4055 patients diagnosed with EGC of differentiated histology who underwent surgery. The association between age and LNM was examined using logistic regression for each T stage separately with adjustments for multiple covariates. We compared LNM rates for each of the Japanese Endoscopic Resection Guidelines criteria in younger (< 40 years) and older patients (40 years). RESULTS The median number of lymph nodes examined was the same for T1a and T1b stages (n = 34). The median number of lymph nodes examined was not significantly different within T1a stage (P = 0.093), but within T1b stage, the number of lymph nodes examined was significantly different (P = 0.019). The highest number was between 50 and 59 years (median = 37), and the lowest number was in the 20 to 49 years and older than 70 age brackets (median = 34). LNM rate and age were not significantly associated within each stage (P values 0.269, 0.783 for T1a and T1b, respectively). Among patients fulfilling endoscopic resection criteria, the LNM rate in younger patients was lower than in older patients. CONCLUSIONS In differentiated-type EGC, young age at diagnosis was not associated with LNM rate. Therefore, endoscopic resection criteria for early gastric cancer can be applied to younger patients.
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Jae SY, Laukkanen JA, Choi YH, Franklin BA. Association Between Cardiorespiratory Fitness and Indices of Coronary Artery Calcification in Men. Mayo Clin Proc 2018; 93:665-666. [PMID: 29728205 DOI: 10.1016/j.mayocp.2018.01.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Revised: 01/09/2018] [Accepted: 01/11/2018] [Indexed: 11/25/2022]
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Pyo JH, Ha SY, Hong SN, Chang DK, Son HJ, Kim KM, Kim H, Kim K, Kim JE, Choi YH, Kim YH. Identification of risk factors for sessile and traditional serrated adenomas of the colon by using big data analysis. J Gastroenterol Hepatol 2018; 33:1039-1046. [PMID: 29087626 DOI: 10.1111/jgh.14035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 10/23/2017] [Accepted: 10/24/2017] [Indexed: 12/23/2022]
Abstract
BACKGROUND AND AIM Little is known about the risk factors associated with serrated polyps, because the early studies, which occurred before the new World Health Organization classification was introduced, included mixtures of serrated polyps. This study aimed to evaluate the risk factors associated with the presence of sessile serrated adenomas (SSAs) and traditional serrated adenomas (TSAs) using big data analytics. METHODS Using a case-control design, we evaluated the risk factors associated with the presence of SSAs and TSAs. Subjects who underwent colonoscopies from 2002 to 2012 as part of the comprehensive health screening programs undertaken at the Samsung Medical Center, Korea, participated in this study. RESULTS Of the 48 677 individuals who underwent colonoscopies, 183 (0.4%) had SSAs and 212 (0.4%) had TSAs. The multivariate analysis determined that being aged ≥ 50 years (odds ratio [OR] 1.91, 95% confidential interval [CI] 1.27-2.90, P = 0.002) and a history of colorectal cancer among first-degree relatives (OR 3.14, 95% CI 1.57-6.27, P = 0.001) were significant risk factors associated with the presence of SSAs and that being aged ≥ 50 years (OR 2.61, 95% CI 1.79-3.80, P < 0.001), obesity (OR 1.63, 95% CI 1.12-2.36, P = 0.010), and a higher triglyceride level (OR 1.63, 95% CI 1.12-2.36, P = 0.010) were independent risk factors associated with the presence of TSAs. CONCLUSIONS We used big data analytics to determine the risk factors associated with the presence of specific polyp subgroups, and individuals who have these risk factors should be carefully scrutinized for the presence of SSAs or TSAs during screening colonoscopies.
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Kim MJ, Kim SS, Park KJ, An HJ, Choi YH, Lee NH, Hyun CG. Methyl jasmonate inhibits lipopolysaccharide-induced inflammatory cytokine production via mitogen-activated protein kinase and nuclear factor-κB pathways in RAW 264.7 cells. DIE PHARMAZIE 2018; 71:540-543. [PMID: 29441852 DOI: 10.1691/ph.2016.6647] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 09/29/2022]
Abstract
Methyl jasmonate is an important signaling molecule involved in plant defense as well as in the regulation of plant growth and development. Despite its various functions in plants, its effects on animal cells have not been widely studied and no report has been issued on the molecular aspects of its anti-inflammatory effect. In the present study, we investigated the in vitro anti-inflammatory properties of methyl jasmonate in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Methyl jasmonate treatment effectively inhibited LPS-induced production of pro-inflammatory mediators (nitric oxide and prostaglandin E2) and cytokines (tumor necrosis factor-α, interleukin (IL)-1β, and IL-6) in a concentration-dependent manner. Furthermore, it attenuated the LPS-induced activation of nuclear factor-κB (NF-κB) by suppressing the degradation of the inhibitor of κB-α (IκB-α). Additionally, methyl jasmonate dose-dependently blocked the phosphorylation of mitogen-activated protein kinases (MAPKs), i.e., p38 kinase, extracellular signal-regulated kinase (ERK) 1/2, and c-Jun N-terminal kinase (JNK), in these cells. These results suggest that methyl jasmonate attenuated the LPS-induced release of pro-inflammatory mediators and cytokines by suppressing the activation of MAPK (JNK, ERK and p38) and NF-κB signaling. This study not only demonstrated that methyl jasmonate exerts anti-inflammatory activities in macrophages but also revealed its potential as a candidate for the treatment of various inflammation-associated diseases.
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Jae SY, Bunsawat K, Choi YH, Kim YS, Touyz RM, Park JB, Franklin BA. Relation of serum uric acid to an exaggerated systolic blood pressure response to exercise testing in men with normotension. J Clin Hypertens (Greenwich) 2018; 20:551-556. [DOI: 10.1111/jch.13219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 11/01/2017] [Accepted: 11/07/2017] [Indexed: 11/30/2022]
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Nguyen TL, Choi YH, Aung YK, Evans CF, Trinh NH, Li S, Dite GS, Kim MS, Brennan PC, Jenkins MA, Sung J, Song YM, Hopper JL. Breast Cancer Risk Associations with Digital Mammographic Density by Pixel Brightness Threshold and Mammographic System. Radiology 2018; 286:433-442. [DOI: 10.1148/radiol.2017170306] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Mishra A, Nam GH, Gim JA, Lee HE, Jo A, Yoon D, Oh S, Kim S, Kim A, Kim DH, Kim YC, Jeong HD, Cha HJ, Choi YH, Kim HS. Comparative evaluation of MCP gene in worldwide strains of Megalocytivirus (Iridoviridae family) for early diagnostic marker. JOURNAL OF FISH DISEASES 2018; 41:105-116. [PMID: 28914452 DOI: 10.1111/jfd.12685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 06/18/2017] [Accepted: 06/19/2017] [Indexed: 06/07/2023]
Abstract
Members of the Iridoviridae family have been considered as aetiological agents of iridovirus diseases, causing fish mortalities and economic losses all over the world. Virus identification based on candidate gene sequencing is faster, more accurate and more reliable than other traditional phenotype methodologies. Iridoviridae viruses are covered by a protein shell (capsid) encoded by the important candidate gene, major capsid protein (MCP). In this study, we investigated the potential of the MCP gene for use in the diagnosis and identification of infections caused Megalocytivirus of the Iridoviridae family. We selected data of 66 Iridoviridae family isolates (53 strains of Megalocytivirus, eight strains of iridoviruses and five strains of Ranavirus) infecting various species of fish distributed all over the world. A total of 53 strains of Megalocytivirus were used for designing the complete primer sets for identifying the most hypervariable region of the MCP gene. Further, our in silico analysis of 102 sequences of related and unrelated viruses reconfirms that primer sets could identify strains more specifically and offers a useful and fast alternative for routine clinical laboratory testing. Our findings suggest that phenotype observation along with diagnosis using universal primer sets can help detect infection or carriers at an early stage.
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Lee DH, Choi YH. Severe Glyphosate-Surfactant Intoxication: Successful Treatment with Continuous Renal Replacement Therapy. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791702400107] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Glyphosate-surfactant is one of the most commonly used herbicides in the world. Its key component, glyphosate, is a competitive inhibitor of the shikimate pathway, a metabolic pathway found only in plants. However, severe intoxication, including lethal cases by ingestion of, glyphosate-surfactant has been reported. We describe the full recovery of two patients from glyphosate-polyoxyethyleneamine surfactant intoxication and multi-organ system failure following continuous renal replacement therapy. Both patients developed persistent shock, acute kidney injury, lactic acidosis, hyperkalaemia and multi-organ failure despite of resuscitation. We believe that continuous renal replacement therapy should be initiated immediately for removal of glyphosate-polyoxyethyleneamine surfactant in patients with signs of cardiopulmonary compromise, lactic acidosis, and renal failure. We propose the addition of glyphosate-polyoxyethyleneamine surfactant to the list of toxins for which early haemodialysis should be indicated.
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Yun HW, Lee DH, Lee JH, Cheon YJ, Choi YH. Serial Serum Cholinesterase Activities as a Prognostic Factor in Organophosphate Poisoned Patients. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791201900203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Objective Organophosphate poisoning is a serious clinical entity and of considerable morbidity and mortality. Several factors have been identified to predict outcomes of organophosphate poisoning. This investigation aims to identify the relationship between the dynamics of serum cholinesterase (SChE) activity and mortality. Methods In this retrospective study, medical records of all patients with acute organophosphate poisoning were reviewed from January 2001 to December 2009. Clinical features, SChE activity, Glasgow Coma Scale, laboratory findings, electrocardiogram finding, management and their outcomes were examined. Results A total of 169 patients were included in this study. A total of 55 patients were enrolled. Deceased patients were 8 in number. Absence of an increase in SChE activity was related with mortality in organophosphate poisoned patients (p value=0.036; odds ratio, 5.445; 95% confidence interval, 1.121-26.551). Conclusions The absence of an increase in SChE activity is associated with higher mortality in organophosphate poisoning. The SChE dynamic activity can provide a guide to physicians in the evaluation and management of organophosphate poisoned patients.
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Cheon YJ, Pyun WB, Lee DH, Choi YH. A Case of Electrocardiographic Change Caused by Subarachnoid Haemorrhage Mimicking Acute Myocardial Infarction. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791201900311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
A 60-year-old woman was admitted to the emergency department due to syncope. The electrocardiogram (ECG) revealed normal sinus rhythm with ST segment elevation in leads I, II, and aVL. There was no stenosis or vasospasm in the coronary arteries. Transient electrocardiographic ST segment elevation which is indistinguishable from that associated with acute myocardial infarction has been reported in patients with subarachnoid hemorrhage (SAH). Until now no case was ever reported with the ECG finding with pattern of posterolateral myocardial infarction in SAH patients. So we describe a patient with SAH mimicking acute myocardial infarction.
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Lee DH, Choi YH. A Case of Pulmonary Pneumatocoele with Splenic Laceration Caused by Vehicular Accident. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791001700512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Traumatic pneumatocoele is an uncommon complication, resulting from air trapping in an area of lung laceration, and may appear a few hours or even immediately after injury. Young adults and children are most commonly affected. Its clinical relevance lies in its rarity, which might mislead emergency physicians to perform unnecessary surgical intervention. We report a 10-year-old boy suffering from traumatic pneumatocoele with spleen laceration caused by blunt trauma. It is important for emergency physicians to be aware of this condition and of its benign course so as to avoid unnecessary operative procedures due to incorrect diagnosis.
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Lee DH, Choi YH. A 67-Year-Old Man with Epistaxis, Melena, Gross Haematuria and Haemarthrosis. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791502200511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Superwarfarins are widely used as rodenticides. They are similar to warfarin, but they are more potent and act longer. In case of poisoning, they cause severe bleeding, usually from multiple sites. Prolonged treatment with high doses of vitamin K and/or fresh frozen plasma (FFP) transfusions may be necessary. Awareness of the problem of superwarfarin intoxication among physicians remains low and cases may go undiagnosed for days or weeks, resulting in increased morbidity and even mortality. We presented a case of delayed diagnosis of superwarfarin ingestion. The patient presented to emergency department with epistaxis, melena, and gross haematuria. He was treated with vitamin K and the International Normalised Ratio (INR) dropped from >7.0 to 1.4. The patient was discharged. However, 3 weeks later, the patient presented with haemarthrosis. Blood investigation revealed INR value >7.0 again. The patient finally received treatment with FFP and vitamin K. This case illustrates the importance to consider superwarfarin ingestion when patients presented with poisoning with coagulopathy. (Hong Kong j.emerg.med. 2015;22:324-327)
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Kim TJ, Kim JE, Choi YH, Hong SN, Kim YH, Chang DK, Rhee PL, Kim MJ, Jung SH, Son HJ. Obesity-related parameters and colorectal adenoma development. J Gastroenterol 2017; 52:1221-1229. [PMID: 28197803 DOI: 10.1007/s00535-017-1319-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 02/02/2017] [Indexed: 02/04/2023]
Abstract
BACKGROUND Obesity increases the risk of colorectal adenoma and colorectal cancer. However, the obesity-related parameters that are best for assessing the risk of colorectal adenoma development remain unclear. We analyzed the parameters that may best describe the association between obesity and colorectal adenoma development. METHODS In this retrospective cohort study, 3405 individuals underwent screening colonoscopy during routine health examinations. We measured body mass index; waist circumference; and metabolic parameters such as high-density lipoprotein-cholesterol, glucose, triglyceride, and systolic blood pressure. We analyzed the risk of developing colorectal adenoma, relative to obesity-related parameters, over a mean interval of 5.8 years from baseline colonoscopy. RESULTS In a multivariate analysis, waist circumference was the only obesity-related marker associated with an increased risk of metachronous colorectal adenoma. Men with waist circumferences ≥85 cm and women with waist circumference ≥82 cm had a 31% increased risk of metachronous colorectal adenoma compared to those with smaller waist circumferences [odds ratio (OR) 1.31; 95% confidence interval (CI, 1.09-1.57)]. Other factors associated with metachronous colorectal adenoma were age (OR, 1.03; 95% CI 1.02-1.04), male sex (OR 1.49; 95% CI 1.17-1.88), alcohol consumption ≥3/week (OR 1.33; 95% CI 1.10-1.62), the number of adenoma at baseline (OR 1.21; 95% CI 1.10-1.33), and the presence of advanced adenoma at baseline (OR 1.60; 95% CI 1.24-2.06). CONCLUSIONS Our findings suggest that central obesity, represented by waist circumference, is a significant predictor of metachronous colorectal adenoma, independent of body mass index and other metabolic variables.
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Kim EJ, Kwak YG, Park SH, Kim SR, Shin MJ, Yoo HM, Han SH, Kim DW, Choi YH, Yoo JH. Trends in device utilization ratios in intensive care units over 10-year period in South Korea: device utilization ratio as a new aspect of surveillance. J Hosp Infect 2017; 100:e169-e177. [PMID: 29042233 DOI: 10.1016/j.jhin.2017.10.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 10/10/2017] [Indexed: 11/30/2022]
Abstract
BACKGROUND Device-associated infection (DAI) is an important issue related to patient safety. It is important to reduce unnecessary device utilization in order to decrease DAI rates. AIM To investigate the time trend of device utilization ratios (DURs) of voluntarily participating hospitals, collected over a 10-year period through the Korean National Healthcare-associated Infections Surveillance System (KONIS). METHODS DURs from 2006 to 2015 in 190 intensive care units (ICUs) participating in KONIS were included in this study. DURs were calculated as the ratio of device-days to patient-days. The pooled incidences of DAIs and DURs were calculated for each year of participation, and the year-wise trends were analysed. FINDINGS Year-wise ventilator utilization ratio (V-DUR) increased significantly from 0.40 to 0.41 (F = 6.27, P < 0.01), urinary catheter utilization ratio (U-DUR) increased non-significantly from 0.83 to 0.84 (F = 1.66, P = 0.10), and C-line utilization ratio (CL-DUR) decreased non-significantly from 0.55 to 0.51 (F = 1.62, P = 0.11). In the subgroup analysis, 'medical ICU' (F = 2.79, P < 0.01) and 'hospital with >900 beds' (F = 3.07, P < 0.01) were associated with the significant increase in V-DUR. CONCLUSION In Korea, V-DUR showed a significant, year-wise increasing trend. The trends for U-DUR and CL-DUR showed no significant decrease. Efforts are required to ensure the reduction of DURs.
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Nkenyereye L, Kwon J, Choi YH. Secure and Lightweight Cloud-Assisted Video Reporting Protocol over 5G-Enabled Vehicular Networks. SENSORS 2017; 17:s17102191. [PMID: 28946633 PMCID: PMC5676728 DOI: 10.3390/s17102191] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 09/17/2017] [Accepted: 09/18/2017] [Indexed: 11/17/2022]
Abstract
In the vehicular networks, the real-time video reporting service is used to send the recorded videos in the vehicle to the cloud. However, when facilitating the real-time video reporting service in the vehicular networks, the usage of the fourth generation (4G) long term evolution (LTE) was proved to suffer from latency while the IEEE 802.11p standard does not offer sufficient scalability for a such congested environment. To overcome those drawbacks, the fifth-generation (5G)-enabled vehicular network is considered as a promising technology for empowering the real-time video reporting service. In this paper, we note that security and privacy related issues should also be carefully addressed to boost the early adoption of 5G-enabled vehicular networks. There exist a few research works for secure video reporting service in 5G-enabled vehicular networks. However, their usage is limited because of public key certificates and expensive pairing operations. Thus, we propose a secure and lightweight protocol for cloud-assisted video reporting service in 5G-enabled vehicular networks. Compared to the conventional public key certificates, the proposed protocol achieves entities’ authorization through anonymous credential. Also, by using lightweight security primitives instead of expensive bilinear pairing operations, the proposed protocol minimizes the computational overhead. From the evaluation results, we show that the proposed protocol takes the smaller computation and communication time for the cryptographic primitives than that of the well-known Eiza-Ni-Shi protocol.
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Choi YH, Lim DH, Jeong JH, Park D, Jeong KS, Kim M, Song A, Chung HS, Chung KB, Yi Y, Cho MH. Characterization of Rotational Stacking Layers in Large-Area MoSe 2 Film Grown by Molecular Beam Epitaxy and Interaction with Photon. ACS APPLIED MATERIALS & INTERFACES 2017; 9:30786-30796. [PMID: 28809109 DOI: 10.1021/acsami.7b05475] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Transition metal dichalcogenides (TMDCs) are promising next-generation materials for optoelectronic devices because, at subnanometer thicknesses, they have a transparency, flexibility, and band gap in the near-infrared to visible light range. In this study, we examined continuous, large-area MoSe2 film, grown by molecular beam epitaxy on an amorphous SiO2/Si substrate, which facilitated direct device fabrication without exfoliation. Spectroscopic measurements were implemented to verify the formation of a homogeneous MoSe2 film by performing mapping on the micrometer scale and measurements at multiple positions. The crystalline structure of the film showed hexagonal (2H) rotationally stacked layers. The local strain at the grain boundaries was mapped using a geometric phase analysis, which showed a higher strain for a 30° twist angle compared to a 13° angle. Furthermore, the photon-matter interaction for the rotational stacking structures was investigated as a function of the number of layers using spectroscopic ellipsometry. The optical band gap for the grown MoSe2 was in the near-infrared range, 1.24-1.39 eV. As the film thickness increased, the band gap energy decreased. The atomically controlled thin MoSe2 showed promise for application to nanoelectronics, photodetectors, light emitting diodes, and valleytronics.
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Jae SY, Babu AS, Yoon ES, Kurl S, Laukkanen JA, Choi YH, Franklin BA. Impact of Cardiorespiratory Fitness and Risk of Systemic Hypertension in Nonobese Versus Obese Men Who Are Metabolically Healthy or Unhealthy. Am J Cardiol 2017; 120:765-768. [PMID: 28705382 DOI: 10.1016/j.amjcard.2017.05.054] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 05/17/2017] [Accepted: 05/31/2017] [Indexed: 12/13/2022]
Abstract
Few data are available regarding the influence of body phenotype on systemic hypertension (SH) and whether cardiorespiratory fitness (CRF) attenuates this relation. We tested the hypothesis that obesity phenotypes and CRF would predict incident hypertension, evaluating 3,800 Korean men who participated in 2 health examinations in1998 to 2009. All participants were normotensive at baseline and were divided into 4 groups based on body mass index using the Asia-Pacific descriptors for obesity and metabolic health status and the National Cholesterol Education Program's adult treatment panel III (ATP-III) criteria. A metabolically healthy obese (MHO) phenotype was defined as a body mass index of ≥25 kg/m2 with <2 metabolic abnormalities. CRF was directly measured by peak oxygen uptake, and the participants were divided into unfit and fit categories based on age-specific peak oxygen uptake percentiles. Compared with the metabolically healthy nonobese phenotype, MHO and metabolically unhealthy nonobese (MUNO) phenotypes were at increased risk of SH (relative risk [RR] = 1.47; 95% confidence interval [CI], 1.07 to 2.02 and 1.62, 1.21 to 2.16) after adjusting for potential confounders. Joint analysis showed that MHO or MUNO unfit men had 1.91 and 2.27 greater risk of incident SH, respectively. However, MHO fit men had no significant RR of incident SH (RR 1.37; 95% CI, 0.93 to 2.03), whereas MUNO fit men remained at increased risk (RR 1.48; 95% CI, 1.04 to 2.11) compared with their metabolically healthy nonobese fit counterparts. In conclusion, MHO and MUNO men were at increased risk of SH, but these risks were attenuated by fitness.
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Jae SY, Kurl S, Laukkanen JA, Yoon ES, Choi YH, Fernhall B, Franklin BA. Relation of heart rate recovery after exercise testing to coronary artery calcification. Ann Med 2017; 49:404-410. [PMID: 28166422 DOI: 10.1080/07853890.2017.1292044] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND We examined whether slow heart rate recovery (HRR) after exercise testing as an estimate of impaired autonomic function is related to coronary artery calcification (CAC), an emerging marker of coronary atherosclerosis. METHODS We evaluated 2088 men who participated in a health-screening program that included measures of CAC and peak or symptom-limited cardiopulmonary exercise testing. HRR was calculated as the difference between peak heart rate (HR) during exercise testing and the HR at 2 min of recovery after peak exercise. We measured CAC using multidetector computed tomography to calculate the Agatston coronary artery calcium score. Advanced CAC was defined as a mean CAC >75th percentile for each age group. RESULTS HRR was negatively correlated with CAC (r = -.14, p < .01). After adjusting for conventional risk factors, participants in the lowest quartile of HRR (<38 bpm) were 1.59 times (95% CI: 1.17-2.18; p < .05) more likely to have advanced CAC than their counterparts in the highest quartile of HRR (>52 bpm). Each 1 bpm decrease in HRR was associated with 1% increase in advanced CAC after adjusting for potential confounders. CONCLUSIONS An attenuated HRR after exercise testing is associated with advanced CAC, independent of coronary risk factors and other related hemodynamic response. KEY MESSAGES Slow heart rate recovery (HRR) after maximal exercise testing, indicating decreased autonomic function, is associated with an increased risk of cardiovascular event and mortality. Slow HRR has been linked with the occurrence of malignant ventricular arrhythmias, but it remains unclear whether slow HRR is associated with an increased risk of coronary artery calcification (CAC), an emerging marker of coronary atherosclerosis. An attenuated HRR after exercise testing was associated with advanced CAC, independent of coronary risk factors and other potential hemodynamic confounder, supporting the hypothesis that slow HRR is related to the burden of atherosclerotic coronary artery disease.
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Kim TJ, Shin HY, Chang Y, Kang M, Jee J, Choi YH, Ahn HS, Ahn SH, Son HJ, Ryu S. Metabolically healthy obesity and the risk for subclinical atherosclerosis. Atherosclerosis 2017; 262:191-197. [DOI: 10.1016/j.atherosclerosis.2017.03.035] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 02/27/2017] [Accepted: 03/22/2017] [Indexed: 01/23/2023]
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Lee SM, Cheon JE, Choi YH, Kim IO, Kim WS, Cho HH, Lee JY, Wang KC. Limited Dorsal Myeloschisis and Congenital Dermal Sinus: Comparison of Clinical and MR Imaging Features. AJNR Am J Neuroradiol 2017; 38:176-182. [PMID: 27765739 DOI: 10.3174/ajnr.a4958] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 08/15/2016] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE While limited dorsal myeloschisis is a distinctive form of spinal dysraphism, it may be confused with congenital dermal sinus. The aim of this study was to describe clinical and MR imaging findings of limited dorsal myeloschisis that can distinguish it from congenital dermal sinus. MATERIALS AND METHODS We retrospectively reviewed the clinical and MR imaging findings of 12 patients with limited dorsal myeloschisis and 10 patients with congenital dermal sinus. Skin abnormalities, neurologic deficits, and infectious complication were evaluated on the basis of clinical information. We evaluated the following MR imaging features: visibility of the tract along the intrathecal course, attachment site of the tract, level of the conus medullaris, shape of the spinal cord, and presence of intradural lesions such as dermoid/epidermoid tumors. RESULTS A crater covered with pale epithelium was the most common skin lesion in limited dorsal myeloschisis (10/12, 83%). Infectious complications were common in congenital dermal sinus (6/10, 60%), whereas none were found in limited dorsal myeloschisis (P = .003). The following MR imaging findings were significantly different between the 2 groups (P < .05): 1) higher visibility of the intrathecal tract in limited dorsal myeloschisis (10/12, 83%) versus in congenital dermal sinus (1/10, 10%), 2) the tract attached to the cord in limited dorsal myeloschisis (12/12, 100%) versus various tract attachments in congenital dermal sinus, 3) dorsal tenting of the cord in limited dorsal myeloschisis (10/12, 83%) versus in congenital dermal sinus (1/10, 10%), and 4) the presence of dermoid/epidermoid tumors in congenital dermal sinus (6/10, 60%) versus none in limited dorsal myeloschisis. CONCLUSIONS Limited dorsal myeloschisis has distinct MR imaging features: a visible intrathecal tract with dorsal tenting of the cord at the tract-cord union. Limited dorsal myeloschisis was not associated with infection and dermoid/epidermoid tumors.
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Kim YG, Song JB, Choi YH, Yang DG, Kim SG, Lee HG. Investigation on quench initiation and propagation characteristics of GdBCO coil co-wound with a stainless steel tape as turn-to-turn metallic insulation. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:114701. [PMID: 27910603 DOI: 10.1063/1.4966676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This paper investigates the quench initiation and propagation characteristics of a metallic insulation (MI) coil by conducting thermal quench tests for a GdBCO single-pancake coil co-wound with a stainless steel tape as the turn-to-turn MI. The test results confirmed that the MI coil exhibited superior thermal and electrical stabilities compared to the conventional coils co-wound with organic insulation material because the operating current could flow along the radial direction due to the existence of a turn-to-turn contact when a local hot spot was generated. The results of the quench test at a heater current (Ih) of 12, 13, and 14 A indicate that the MI coil possesses a self-protecting characteristic resulting from the "current bypass" through the turn-to-turn contact. However, the test coil was not self-protecting at Ih = 15 A because the Joule heat energy generated by the radial current flow was not completely dissipated due to the characteristic resistance of the metallic insulation tape and the non-superconducting materials, including the substrate, stabilizer, and buffer layers within the high-temperature superconductor (HTS) tape. Even though the MI coil possesses superior thermal and electrical stability relative to those of conventional HTS coils co-wound with an organic material as turn-to-turn insulation, it is essential to consider the critical role of the Joule heat energy resulting from the operating current and stored magnetic energy as well as the characteristic resistances in order to further develop self-protective 2G HTS magnets.
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