Young Sik Park

Seoul National University, Sŏul, Seoul, South Korea

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Publications (70)136.14 Total impact

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    ABSTRACT: Background/aims: Patients with liver cirrhosis (LC) are at risk for critical events leading to Intensive Care Unit (ICU) admission. Coagulopathy in cirrhotic patients is complex and can lead to bleeding as well as thrombosis. The aim of this study was to investigate bleeding complications in critically ill patients with LC admitted to a medical ICU (MICU). Methods: All adult patients admitted to our MICU with a diagnosis of LC from January 2006 to December 2012 were retrospectively assessed. Patients with major bleeding at the time of MICU admission were excluded from the analysis. Results: A total of 205 patients were included in the analysis. The median patient age was 62 years, and 69.3% of the patients were male. The most common reason for MICU admission was acute respiratory failure (45.4%), followed by sepsis (27.3%). Major bleeding occurred in 25 patients (12.2%). The gastrointestinal tract was the most common site of bleeding (64%), followed by the respiratory tract (20%). In a multivariate analysis, a low platelet count at MICU admission (odds ratio [OR], 0.98; 95% confidence interval [CI], 0.97 to 0.99) and sepsis (OR, 8.35; 95% CI, 1.04 to 67.05) were independent risk factors for major bleeding. The ICU fatality rate was significantly greater among patients with major bleeding (84.0% vs. 58.9%, respectively; p = 0.015). Conclusions: Major bleeding occurred in 12.2% of critically ill cirrhotic patients admitted to the MICU. A low platelet count at MICU admission and sepsis were associated with an increased risk of major bleeding during the MICU stay. Further study is needed to better understand hemostasis in critically ill patients with LC.
    No preview · Article · Jan 2016 · The Korean Journal of Internal Medicine
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    ABSTRACT: Background: According to the Fletcher-Peto curve, rate of decline in forced expiratory volume in 1-second (FEV1) accelerates as age increases. However, recent studies have not demonstrated that the rate of FEV1 decline accelerates with age among COPD patients. The objective of the study is to evaluate annual rate of FEV1 decline as age increases among COPD patients. Methods: In this retrospective cohort study, we enrolled COPD patients who were followed up at two tertiary care university hospitals from January 2000 to August 2013. COPD was defined as post-bronchodilator (BD) FEV1/forced vital capacity (FVC) of <0.7. All participants had more than two spirometries, including BD response. Age groups were categorized as follows: below versus above median age or four quartiles. Results: A total of 518 participants (94.2% male; median age, 67 years; range, 42-90 years) were included. Mean absolute and predictive values of post-BD FEV1 were 1.57±0.62 L and 52.53%±18.29%, respectively. Distribution of Global initiative for Chronic Obstructive Lung Disease groups did not show statistical differences between age groups categorized by two different criteria. After grouping the population by age quartiles, the rate of FEV1 decline was faster among older patients than younger ones whether expressed as absolute value (-10.60±5.57 mL/year, -15.84±6.01 mL/year, -18.63±5.53 mL/year, 32.94±6.01 mL/year, respectively; P=0.048) or predicted value (-0.34%±0.19%/year, -0.53%±0.21%/year, -0.62%±0.19%/year, -1.26%±0.21%/year, respectively, P=0.010). Conclusion: As suggested conceptually by the Fletcher-Peto curve, annual FEV1 decline among COPD patients is accelerated among older patients than younger ones.
    Preview · Article · Dec 2015 · International Journal of COPD
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    ABSTRACT: Objectives: Our study aimed to determine the predictive and prognostic values of the serum neuron-specific enolase (NSE) level in patients who had non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations and who had been treated with EGFR-tyrosine kinase inhibitors (TKIs). Materials and methods: We retrospectively analyzed 151 patients who had NSCLC harboring EGFR mutations and had received either gefitinib or erlotinib as first-line treatment between 2005 and 2014. The serum NSE level was measured before initiation of EGFR-TKI treatment. Results: Of the 151 patients, 92 (60.9%) had elevated NSE levels (> 16.3 ng/mL). Patients with elevated NSE levels showed significantly shorter progression-free survival (PFS) after EGFR-TKI treatment than those with normal NSE levels (median PFS, 10.5 months vs. 15.4 months; P = .034). Multivariate analysis demonstrated that elevated NSE levels (hazard ratio [HR], 1.656; P = .017), CNS metastasis at diagnosis (HR, 1.567; P = .037), and male gender (HR, 1.840; P = .005) were independent predictive factors for short PFS. A significant difference in overall survival (OS) was observed between patient groups with elevated and normal NSE levels (median OS, 17.0 months vs. 29.1 months; P < .001), and serum NSE level remained an independent prognostic factor for OS in multivariate analysis (HR, 2.671; P < .001). Conclusion: Patients with elevated serum NSE levels have significantly shorter PFS and OS. The NSE level is both a predictive marker of EGFR-TKI treatment and a prognostic marker in EGFR-mutant NSCLC patients.
    No preview · Article · Nov 2015 · Clinical Lung Cancer
  • Jaeyoung Cho · Young Sik Park

    No preview · Article · Nov 2015 · The American Journal of the Medical Sciences
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    ABSTRACT: Background/Aims: Whether the causative organism influences the clinical course of pneumonia in the intensive care unit (ICU) is controversial. We assessed the clinical manifestations and prognosis of pneumonia according to the causative pathogens in patients in a medical ICU. Methods: A retrospective observational study was performed in a medical ICU. Among 242 patients who were admitted to the ICU, 103 who were treated for pneumonia were analyzed. Results: The causative pathogen was identified in 50 patients (49.0%); 22 patients (21.6%) had multidrug-resistant (MDR) pathogens. The distribution of causative micro-organisms was Staphylococcus aureus (20%), Pseudomonas species (16%), Klebsiella pneumoniae (14%), and Acinetobacter baumannii (12%). No significant difference in ICU mortality rate, duration of ICU stay, duration of mechanical ventilation, or frequencies of re-intubation and tracheostomy were detected based on the identification of any pathogen. In sub-analyses according to the pneumonia classification, the number of pathogens identified did not differ between pneumonia types, and a higher incidence of identified MDR pathogens was detected in the hospital-acquired pneumonia group than in the community-acquired or healthcare- acquired pneumonia groups. However, the clinical outcomes of pneumonia according to identification status and type of pathogen did not differ significantly between the groups. Conclusions: Neither the causative micro-organism nor the existence of MDR pathogens in critically ill patients with pneumonia was associated with the clinical outcome of pneumonia, including ICU mortality. This result was consistent regardless of the pneumonia classification.
    No preview · Article · Oct 2015 · The Korean Journal of Internal Medicine
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    Jimyung Park · Hyung-Jun Kim · Jee Min Kim · Young Sik Park
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    ABSTRACT: Pulmonary arteriovenous malformations (AVMs) are caused by abnormal vascular communications between the pulmonary arteries and pulmonary veins, which lead to the blood bypassing the normal pulmonary capillary beds. Pulmonary AVMs result in right-to-left shunts, resulting in hypoxemia, cyanosis, and dyspnea. Clinical signs and symptoms vary depending on the size, number, and flow of the AVMs. Transcatheter embolization is the treatment of choice for pulmonary AVMs. However, this method can fail if the AVM is large or has multiple complex feeding arteries. Surgical resection is necessary in those kind of cases. Here, we report the case of a patient with a 6-cm pulmonary AVM with multiple feeding arteries that was successfully treated by repeated coil embolization without surgery.
    Preview · Article · Oct 2015 · Tuberculosis and Respiratory Diseases
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    ABSTRACT: Background Tiotropium failed to slow the annual rate of forced expiratory volume in 1 second (FEV1) decline in chronic obstructive pulmonary disease (COPD) patients with <70% predicted FEV1. However, the rate of FEV1 decline is known to be faster at early stages, which suggests that the effects of tiotropium may be more prominent in early-stage of COPD patients. The aim of this study was to test the hypothesis that tiotropium modifies the rate of FEV1 decline in COPD patients with an FEV1≥70%. Methods We retrospectively reviewed the records of COPD patients diagnosed between January 1, 2004, and July 31, 2012, at Seoul National University Hospital, Seoul National University Bundang Hospital, and Seoul Metropolitan Government-Seoul National University Boramae Medical Center. The inclusion criteria were as follows: age ≥40 years, postbron-chodilator (BD) FEV1≥70% of predicted and FEV1/FVC (forced vital capacity) <0.70, and spirometry more than two times at certain times of the year. Conversely, the exclusion criteria were as follows: asthma, lung cancer, pulmonary tuberculosis, pulmonary resection, or long-term use of a short-acting muscarinic antagonist. The annual lung function decline in patients using tiotropium was compared with that in patients not using the drug. Results Of the 587 patients enrolled in the study, 257 took tiotropium. Following propensity score matching, 404 patients were included in the analysis. The mean annual rate of post-BD FEV1 decline was 23.9 (tiotropium) and 22.5 (control) mL/yr (P=0.86); corresponding pre-BD values were 30.4 and 21.9 mL/yr (P=0.31), respectively. Mean annual rate of post-BD FVC decline was 55.1 (tiotropium) and 43.5 (control) mL/yr (P=0.33); corresponding pre-BD values were 37.1 and 33.3 mL/yr (P=0.13). Conclusion Therefore, tiotropium does not reduce the rate of lung function decline in COPD patients with FEV1≥70%.
    Preview · Article · Oct 2015 · International Journal of COPD
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    ABSTRACT: Background: Rapid on-site evaluation (ROSE) for endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has been advocated to qualitatively diagnose biopsy samples. However, adequate ROSE criteria during EBUS-TBNA are unclear. The aim of this study was to determine adequacy criteria of ROSE in EBUS-TBNA samples and suggest an appropriate algorithm. Methods: Patients who underwent EBUS-TBNA for nodal evaluation between March and July 2013 at Seoul National University Hospital were included prospectively. The ROSE slides were reviewed independently by two pathologists, and the results were compared to the final pathologic results. Diagnostic yields, sensitivity, specificity, and accuracy were calculated in order to make nodal evaluations. Results: EBUS-TBNA was performed on 300 lymph nodes in 133 patients. Samples were nondiagnostic in 7.7%, 6.3%, and 1.7% of the cytologic, histologic, and overall pathologic results, respectively. On the ROSE slides, a large tissue core size (≥2 cm), microscopic anthracotic pigment (MAP), and increased lymphocyte density (LD; ≥40 cells/field [40×, mean of 10 fields]) were significantly associated with adequate final cytologic or histologic results. Malignant cells were not statistically associated with adequacy but were considered a parameter indicating an adequate diagnosis. Using four sequential criteria, tissue core size, the presence of malignant cell, MAP, and LD ≥40 cells/field, the sensitivity and accuracy rates of ROSE increased from 64.4% to 98.6% and from 64.7% to 97.3%, respectively. Conclusions: A high adequacy rate of ROSE in EBUS-TBNA can be achieved by sequentially applying four criteria: tissue core size, malignant cells, MAP, and increased LD.
    No preview · Article · Oct 2015 · The Annals of thoracic surgery
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    ABSTRACT: Background: Although exposure to second-hand smoke (SHS) has been associated with various medical conditions, only limited data are available on its association with health-related quality of life (HRQOL), particularly data obtained with the EQ-5D or EQ visual analogue scale (VAS). Methods: This cross-sectional study evaluated 10,532 adult never-smokers who participated in the fifth Korea National Health and Nutrition Examination Survey. By using linear regression models to adjust for possible confounders and incorporating survey weights in analyses, the association between exposure to SHS and HRQOL-measured with the EQ-5D index and the EQ-VAS score-was evaluated. Data were further stratified by the amount of exposure time. Results: After weighted analysis and adjustment, exposure to SHS was significantly associated with lower measures on the EQ-5D index (β = -0.007, P = 0.005) and EQ-VAS score (β = -1.936, P < 0.001). When comparing the unexposed group with the groups exposed <2h/day and ≥2h/day, exposure to a longer duration of SHS was significantly associated with lower scores on the EQ-5D index and the EQ-VAS score. Conclusion: In conclusion, exposure to SHS was associated with reduced HRQOL measured by the EQ-5D index and EQ-VAS score, revealing a dose-response relationship.
    Full-text · Article · Sep 2015 · PLoS ONE
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    ABSTRACT: Background/aims: In assigning patients with chronic obstructive pulmonary disease (COPD) to subgroups according to the updated guidelines of the Global Initiative for Chronic Obstructive Lung Disease, discrepancies have been noted between the COPD assessment test (CAT) criteria and modified Medical Research Council (mMRC) criteria. We investigated the determinants of symptom and risk groups and sought to identify a better CAT criterion. Methods: This retrospective study included COPD patients seen between June 20, 2012, and December 5, 2012. The CAT score that can accurately predict an mMRC grade ≥ 2 versus < 2 was evaluated by comparing the area under the receiver operating curve (AUROC) and by classification and regression tree (CART) analysis. Results: Among 428 COPD patients, the percentages of patients classif ied into subgroups A, B, C, and D were 24.5%, 47.2%, 4.2%, and 24.1% based on CAT criteria and 49.3%, 22.4%, 8.9%, and 19.4% based on mMRC criteria, respectively. More than 90% of the patients who met the mMRC criteria for the 'more symptoms group' also met the CAT criteria. AUROC and CART analyses suggested that a CAT score ≥ 15 predicted an mMRC grade ≥ 2 more accurately than the current CAT score criterion. During follow-up, patients with CAT scores of 10 to 14 did not have a different risk of exacerbation versus those with CAT scores < 10, but they did have a lower exacerbation risk compared to those with CAT scores of 15 to 19. Conclusions: A CAT score ≥ 15 is a better indicator for the 'more symptoms group' in the management of COPD patients.
    Preview · Article · Sep 2015 · The Korean Journal of Internal Medicine

  • No preview · Article · Aug 2015 · Journal of Critical Care
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    ABSTRACT: History of treatment for tuberculosis (TB) is a risk factor for obstructive lung disease. However, it has been unclear whether the clinical characteristics of patients with destroyed lung by TB differ according to the presence or absence of airflow limitation. The objective of the study was to evaluate differences in acute exacerbations and forced expiratory volume in 1 second (FEV1) decline in patients with destroyed lung by TB according to the presence or absence of airflow limitation. We performed a retrospective cohort study and enrolled patients with destroyed lung by TB. The presence of airflow limitation was defined as FEV1/forced vital capacity (FVC) < 0.7. One hundred and fifty-nine patients were enrolled, and 128 (80.5%) had airflow limitation. The proportion of patients who experienced acute exacerbation was higher in patients with airflow limitation compared to those without (89.1 vs. 67.7%, respectively; P = 0.009). The rate of acute exacerbation was higher in patients with airflow limitation (IRR, 1.19; 95% CI, 1.11-1.27). Low body mass index (X vs. X + 1; HR, 0.944; 95% CI, 0.895-0.996) in addition to airflow limitation (HR, 1.634; 95% CI, 1.012-2.638), was an independent risk factor for acute exacerbation. The annual decline of FEV1 was 2 mL in patients with airflow limitation and 36 mL in those without (P < 0.001). In conclusion, the presence of airflow limitation is an independent risk factor for acute exacerbation in patients with the destroyed lung by TB.
    Preview · Article · May 2015 · Journal of Korean Medical Science
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    ABSTRACT: Despite being a major public health problem, chronic obstructive pulmonary disease (COPD) remains underdiagnosed, and only 2.4% COPD patients are aware of their disease in Korea. The objective of this study was to estimate the prevalence of COPD detected by spirometry performed as a preoperative screening test and to determine the Global Initiative for Chronic Obstructive Lung Disease (GOLD) group distribution and self-awareness of COPD. We reviewed the medical records of adults (age, ≥40 years) who had undergone spirometry during preoperative screening between April and August 2013 at a tertiary hospital in Korea. COPD was defined as a postbronchodilator forced expiratory volume in 1 s/forced vital capacity ratio of <0.7. We analyzed self-administered COPD questionnaires for the assessment of the frequency of acute exacerbation over the previous year and dyspnea severity using the modified Medical Research Council dyspnea scale and COPD assessment test. Among 3029 patients aged >40 years who had undergone spirometry as a preoperative screening test, 474 (15.6%; 404 men; median age, 70 years; range, 44-93 years) were diagnosed with COPD. Only 26 (5.5%) patients reported previous diagnosis of COPD (2.1%), emphysema (0.8%), or chronic bronchitis (2.5%). The GOLD group distribution was as follows: 63.3% in group A, 31.2% in group B, 1.7% in group C, and 3.8% in group D. The prevalence of COPD diagnosed by preoperative spirometry was 15.6%, and only 5.5% patients were aware of their disease. Approximately one-third of the COPD patients belonged to GOLD groups B, C, and D, which require regular treatment.
    Preview · Article · Jan 2015 · PLoS ONE
  • Ha Youn Lee · Joohae Kim · Yong Suk Jo · Young Sik Park
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    ABSTRACT: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a safe and effective diagnostic tool for mediastinal evaluation. The guidelines for mediastinal evaluation of lung cancer were recently revised for both endoscopic procedures and surgical medical staging, and EBUS-TBNA is expected to be used more often in lung cancer diagnosis and staging. The major complication rate reported in previous meta-analyses is very low at 0.07-.15%; however, the mortality rate has not been reported. We present 2 cases of acute bacterial pericarditis after EBUS-TBNA, with 1 case resulting in mortality, and we discuss the appropriate management. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
    No preview · Article · Dec 2014 · European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery
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    ABSTRACT: Background: Multiple comorbidities related to chronic obstructive pulmonary disease (COPD) make it a difficult disease to treat. The relationship between these comorbidities and COPD has not been fully investigated. We aimed to determine whether COPD was independently associated with various comorbidities. Methods: This was a cross-sectional study, which used data from the Korean National Health and Nutrition Examination Survey (KNHANES) V conducted between 2010 and 2012. Survey design analysis was employed to determine the association between COPD and 15 comorbidities. A COPD patient was defined as a smoker with forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) < 0.7 and comorbidities were defined based on objective laboratory findings and questionnaires. Results: Of a total of 9488 patient who underwent spirometry, 744 (7.84%) COPD cases and 3313 non-COPD controls were included in the analyses. Although the prevalence rates of the majority of the comorbidities were high among the COPD patients, only hypertension (adjusted odds ratio [aOR], 1.63; 95% CI, 1.13-2.33 in Stage 1 COPD group; aOR, 1.92; 95% CI, 1.36-2.72 in Stage 2-4 COPD group) and a history of pulmonary tuberculosis (aOR, 3.38; 95% CI, 1.90-5.99 in Stage 2-4 COPD group) were independently associated with COPD after adjustment for age, smoking status, and confounders. Conclusions: Only hypertension and a history of pulmonary tuberculosis were independently associated with COPD after adjustment for confounders among 15 comorbidities. The results suggest that majority of COPD patients might have similar risk factors with its comorbidities, including age and smoking status.
    No preview · Article · Nov 2014 · Respiratory Medicine
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    ABSTRACT: Background Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease of unknown causes. Three proteins (mammalian target of rapamycin, mTOR; zinc finger E-box-binding homeobox 1, ZEB1; Rho-associated, coiled-coil containing protein kinase 1, ROCK1) may be related to pulmonary fibrosis. However, they have not been assessed in human pulmonary fibrosis. We assessed the clinical significance of mTOR, ZEB1, and ROCK1 expression in human pulmonary fibrosis of usual interstitial pneumonia (UIP) pattern. Methods The mTOR, ZEB1, and ROCK1 expression was evaluated by immunohistochemical staining of 30 surgical lung biopsy tissues from 26 IPF and 4 UIP pattern connective tissue disease related interstitial lung disease (CTD-ILD) patients. The expression scores correlated with the clinical features. Results The mTOR, ZEB1 and ROCK1 mainly expressed in alveolar epithelial cells of UIP lungs. The histological fibrosis scores and lung function decline in the strong mTOR expression group were higher than those in the weak and intermediate expression group. Patients with positive ZEB1 expression had higher fibrosis scores and greater decline in carbon monoxide diffusion capacity (DLCO) than patients with negative ZEB1 expression. Patients with positive mTOR or ZEB1 expression had poorer prognosis than that of patients with negative mTOR or ZEB1 expression, although it was not statistically significant. ROCK1 was not associated with the studied clinicopathological features. Conclusions The mTOR and ZEB1 expression in pulmonary fibrosis patients significantly correlated with the fibrosis score and lung function decline, indicating that it may be related to the prognosis of pulmonary fibrosis. Further studies involving large numbers of homogeneous IPF patients are warranted.
    Preview · Article · Oct 2014 · BMC Pulmonary Medicine

  • No preview · Article · Oct 2014 · Chest
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    ABSTRACT: Background: No study has determined whether the risk of mortality predicted by the GAP (gender, age, and physiologic variables) model matches the observed mortality from idiopathic pulmonary fibrosis (IPF) in non-Western populations. We evaluated the clinical course of IPF and validated the GAP model in Korean patients with IPF. Methods: We included 268 patients who received a diagnosis of IPF at Seoul National University Hospital between 2005 and 2009. For each patient, demographics and clinical data, such as lung physiologic parameters at IPF diagnosis, were evaluated. We validated the GAP model using discrimination and calibration to predict the risk of death in Korean patients with IPF. Results: The study population comprised 181 men and 87 women (mean age, 65.9 years). The mean baseline % predicted FVC was 77, and % predicted diffusing capacity of lung for carbon monoxide was 65.9. A total of 157 deaths (58.6%) occurred during follow-up, and the median time to death was 4.64 years. The observed cumulative mortality at 1, 2, and 3 years was 10.4%, 20.9%, and 31.0%, respectively. The GAP model produced estimates of 1-year mortality risk consistent with the observed data (C statistic: GAP calculator, 0.74; GAP index and staging system, 0.72; P < .29). However, calibration of the GAP model at 3 years was not satisfactory. Conclusions: The GAP model showed similar discrimination power compared with the original cohort but did not predict the 3-year risk of death accurately. Further multinational validation studies are needed.
    No preview · Article · Sep 2014 · Chest
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    ABSTRACT: Binaural hearing aids consist of two hearing devices, one for each ear. A new concept of binaural hearing aids is proposed, in which only the master hearing aid contains a Bluetooth chip for receiving stereo audio signals from an external device, and the signal in one channel is sent to the slave hearing aid from the master by a 2.4-GHz Gaussian frequency-shift keying (GFSK) RF transmission method to create the binaural hearing effect. However, a problem arises in regard to the processing necessary for the signal transmission and reception in the two hearing aids, which creates a time delay that causes the precedence effect. Therefore, an audio delay processing algorithm has been designed in the master hearing aid to synchronize with the sound output of the slave hearing aid. Experimental results show that the time difference between the two hearing aids is about 8 µs, which is effective for avoiding the precedence effect. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
    No preview · Article · Sep 2014 · IEEJ Transactions on Electrical and Electronic Engineering
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    ABSTRACT: Introduction The culture-negative conversion rate of sputum after 2 months of treatment in patients with pulmonary tuberculosis (TB) is used as a reliable surrogate marker for relapse after completion of treatment. We hypothesized that culture conversion of sputum at 2 months of anti-TB treatment and the time to culture conversion are different among pulmonary TB patients who are diagnosed using different methods. Methods Culture-confirmed pulmonary TB patients who were diagnosed between 1 January, 2011 and 31 December, 2012 were classified into three groups based on the diagnostic method that prompted treatment initiation: positive acid-fast bacilli (AFB) staining of sputum (smear-positive group), negative AFB staining, but Mycobacterium tuberculosis was cultured from sputum (culture-positive group), and positive AFB staining, positive polymerase chain reaction (PCR) for M. tuberculosis, or culture of M. tuberculosis from a bronchoscopic specimen (bronchoscopy group). Rates of negative mycobacterial culture conversion at 2 months of anti-TB treatment and the time to negative culture conversion of sputum were compared among the three groups. Results A total of 203 patients with culture-confirmed pulmonary TB were included in the final analysis. TB patients in the culture-positive group (94.1%) and the bronchoscopy group (97.6%) showed a higher culture conversion rate at 2 months of treatment than those in the smear-positive group (78.7%, P = 0.001). Additionally, the time to culture conversion was longer in the smear-positive group (median, 40 days) than in the culture-positive (median, 19 days; P = 0.009) and bronchoscopy groups (median, 29 days; P = 0.004). Conclusions The higher culture conversion rate at 2 months and the shorter time to culture conversion among pulmonary TB patients with a negative AFB smear suggests the feasibility of shortening treatment duration and isolation in these patients.
    Preview · Article · Aug 2014 · PLoS ONE

Publication Stats

296 Citations
136.14 Total Impact Points


  • 2009-2015
    • Seoul National University
      • Department of Internal Medicine
      Sŏul, Seoul, South Korea
  • 2003-2015
    • Seoul National University Hospital
      • • Department of Internal Medicine
      • • Department of Pathology
      Sŏul, Seoul, South Korea
  • 2014
    • Chungnam National University
      • Graduate School of Drug Development and Discovery
      Daiden, Daejeon, South Korea
  • 1997-2014
    • Kyungpook National University
      • • Department of Animal Science and Biotechnology
      • • School of Food Science and Biotechnology
      • • Animal Science
      Daikyū, Daegu, South Korea
  • 2012
    • Dongguk University
      • Quantum-functional Semiconductor Research Center
      Sŏul, Seoul, South Korea
  • 2007
    • Korea National Sport University
      Sŏul, Seoul, South Korea