[Show abstract][Hide abstract] ABSTRACT: Background:
Asian dust is known to have harmful effects on the respiratory system. Respiratory conditions are also influenced by environmental conditions regardless of the presence of pollutants. The same pollutant can have different effects on the airway when the air is dry compared with when it is humid. We investigated hospital visits for chronic obstructive pulmonary disease (COPD) and asthma in relation to the environmental conditions.
We conducted a retrospective study using the Korean National Health Insurance Service claims database of patients who visited hospitals in Chuncheon between January 2006 and April 2012. Asian dust, haze, mist, and fog days were determined using reports from the Korea Meteorological Administration. Hospital visits for asthma or COPD on the index days were compared with the comparison days. We used two-way case-crossover techniques with one to two matching.
The mean hospital visits for asthma and COPD were 59.37 ± 34.01 and 10.04 ± 6.18 per day, respectively. Hospital visits for asthma significantly increased at lag0 and lag1 for Asian dust (relative risk [RR], 1.10; 95% confidence interval [CI], 1.01-1.19; p<0.05) and haze (RR, 1.13; 95% CI, 1.06-1.22; p<0.05), but were significantly lower on misty (RR, 0.89; 95% CI, 0.80-0.99; p<0.05) and foggy (RR, 0.89; 95% CI, 0.84-0.93; p<0.05) days than on control days. The hospital visits for COPD also significantly increased on days with Asian dust (RR, 1.29; 95% CI, 1.05-1.59; p<0.05), and were significantly lower at lag4 for foggy days, compared with days without fog (RR, 0.85; 95% CI, 0.75-0.97; p<0.05).
Asian dust showed an association with airway diseases and had effects for several days after the exposure. In contrast to Asian dust, mist and fog, which occur in humid air conditions, showed the opposite effects on airway diseases, after adjusting to the pollutants. It would require more research to investigate the effects of various air conditions on airway diseases.
Tuberculosis and Respiratory Diseases 10/2015; 78(4):326-35. DOI:10.4046/trd.2015.78.4.326
[Show abstract][Hide abstract] ABSTRACT: Endobronchial valve (EBV) therapy is increasingly being seen as a therapeutic option for advanced emphysema, but its clinical utility in Asian populations, who may have different phenotypes to other ethnic populations, has not been assessed.
This prospective open-label single-arm clinical trial examined the clinical efficacy and the safety of EBV in 43 consecutive patients (mean age 68.4±7.5, forced expiratory volume in 1 second [FEV1] 24.5%±10.7% predicted, residual volume 208.7%±47.9% predicted) with severe emphysema with complete fissure and no collateral ventilation in a tertiary referral hospital in Korea.
Compared to baseline, the patients exhibited significant improvements 6 months after EBV therapy in terms of FEV1 (from 0.68±0.26 L to 0.92±0.40 L; P<0.001), 6-minute walk distance (from 233.5±114.8 m to 299.6±87.5 m; P=0.012), modified Medical Research Council dyspnea scale (from 3.7±0.6 to 2.4±1.2; P<0.001), and St George's Respiratory Questionnaire (from 65.59±13.07 to 53.76±11.40; P=0.028). Nine patients (20.9%) had a tuberculosis scar, but these scars did not affect target lobe volume reduction or pneumothorax frequency. Thirteen patients had adverse events, ten (23.3%) developed pneumothorax, which included one death due to tension pneumothorax.
EBV therapy was as effective and safe in Korean patients as it has been shown to be in Western countries. (
International Journal of COPD 08/2015; 10:1501-11. DOI:10.2147/COPD.S85744 · 3.14 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Pleuropulmonary diseases caused by Clostridial species infections are rare, but have a mortality rate of up to 30%. Furthermore, older people are at greater risk of developing invasive clostridium infections, and the majority of reported cases of clostridium empyema have been attributed to iatrogenic trauma or aspiration. The authors report a case of spontaneous empyema caused by Clostridium perfringens. A 72-year-old woman was admitted to Kangwon National University Hospital for empyema. The patient had no history of trauma, a dental procedure, or aspiration, and was treated using empirical antibiotics and by drainage of pleural fluid. Bacteria species that cause empyema are usually not detected, but on the 4th day of admission, C. perfringens was isolated from the pleural space. The patient was continuously treated with antibiotics for C. perfringens and drainage, and was discharged 25 days after admission with almost a fully recovered status. Increased awareness of Clostrium species infection in the elderly is needed to ensure appropriate treatment.
[Show abstract][Hide abstract] ABSTRACT: Multipotent perivascular cells (PVCs) have recently gained attention as an alternative source for cell-based regenerative medicine. Because of their rarity in human tissues, the development of efficient methods to isolate and expand PVCs from various fetal and adult tissues is necessary to obtain a clinically relevant number of cells that maintain progenitor potency. We report a simple non-enzymatic isolation (NE) method of PVCs from human umbilical cord (HUC) and compare its efficiency with the conventional collagenase treatment method (CT) in terms of proliferation, immunophenotype, clonogenic capacity, and differentiation potential. Cells isolated by NE expressed the accepted surface marker profile of PVCs and possessed multilineage differentiation potential. Whereas both methods provided similar patterns or levels of immunophenotypes and proliferation, PVCs obtained by NE maintained a higher level of CD146(+) frequency compared with that of CT over passages and displayed greater in vitro osteogenic differentiation potential and clonogenic capacity than CT-PVCs. We assess the potential of various exogenous factors to boost the proliferation of NE- and CT-PVCs in vitro. Supplementation of basic fibroblast growth factor (bFGF) provided optimal conditions that significantly enhanced their proliferation rate. This treatment drove the cells into S phase and increased the proportion of stage-specific antigen-4-positive population without altering other immunophenotypes. Thus, the NE method with bFGF supplementation offers an alternative way for obtaining sufficient numbers of HUCPVCs that have good clonogenic and differentiation potential and that are applicable at therapeutic doses for regenerative medicine.
Cell and Tissue Research 12/2014; 359(3). DOI:10.1007/s00441-014-2066-7 · 3.57 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Although many patients with severe emphysema have benefited from bronchoscopic lung volume reduction (BLVR) worldwide, experience of BLVR in Asian emphysema patients is scarce. Between July 2012 and March 2013, seven patients with advanced heterogeneous emphysema underwent BLVR in the Asan Medical Center. They had severe dyspnea and poor lung function (Modified Medical Research Council dyspnea scale 3-4; median forced expiratory volume in 1 sec [FEV1], 0.59 L [19.0 % predicted]; median 6-min walk distance [6MWD], 195 m). Endobronchial valves were inserted into the target lobe which was most hyperinflated and least perfused, and had no collateral ventilation with other lobes. Six patients showed clinical improvement after 1 month. Of them, 2 patients improved to dyspnea scale 1 and 4 patients did to scale 2 (P = 0.026). The median FEV1 increased from 0.59 to 0.89 L (51%; P = 0.028) and the median 6MWD increased from 195 to 252 m (29.2%; P = 0.028). Two patients developed a pneumothorax (one requiring drainage) and one patient experienced slight hemoptysis; however, there were no other serious adverse events. BLVR is effective in Asian advanced emphysema patients, with noted clinical improvements in lung function and exercise capacity.
Journal of Korean Medical Science 10/2014; 29(10):1404-10. DOI:10.3346/jkms.2014.29.10.1404 · 1.27 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Introduction
The development of reliable gene expression profiling technology increasingly impacts our understanding of lung cancer biology. Here, we used RNA sequencing (RNA-Seq) to compare the transcriptomes of non-small cell lung cancer (NSCLC) and normal lung tissues and to investigate expression in lung cancer tissues.
We enrolled 88 male patients (mean age, 61.2 years) with NSCLC. RNA-Seq was performed on 88 pairs of NSCLC tumor tissue and non-tumor tissue from 54 patients with adenocarcinoma and 34 patients with squamous cell carcinoma. Immunohistochemistry was performed to validate differential candidate gene expression in a different NSCLC group.
RNA-Seq produced 25.41 × 106 (± 8.90 × 106) reads in NSCLC tissues and 24.70 × 106 (± 4.70 × 106) reads in normal lung tissues [mean (± standard deviation)]. Among the genes expressed in both tissues, 335 were upregulated and 728 were downregulated ≥ 2-fold (P < 0.001). Four upregulated genes–CBX3, GJB2, CRABP2, and DSP–not previously reported in lung cancer were studied further. Their altered expression was verified by immunohistochemistry in a different set of NSCLC tissues (n = 154). CBX3 was positive in 90.3% (139 cases) of the samples; GJB2, in 22.7% (35 cases); CRABP2, in 72.1% (111 cases); and DSP, in 17.5% (27 cases). The positive rate of CRABP2 was higher in adenocarcinoma than squamous cell carcinoma (p < 0.01).
CBX3 and CRABP2 expression was markedly increased in lung cancer tissues and especially CRABP2 may be promising candidate genes in lung adenocarcinoma.
[Show abstract][Hide abstract] ABSTRACT: Background
Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation and results from environmental factors and genetic factors. Although cigarette smoking is a major risk factor, other environmental exposures can influence COPD. The purpose of this study is to investigate the clinical characteristics of COPD according to the history of environmental exposure.
The study population comprised of 347 subjects with COPD who were recruited from the pulmonary clinics of 14 hospitals within the Korean Obstructive Lung Disease Study Group. We classified environmental exposures according to history of living near factory, and direct exposure history to firewood or briquette. According to living environmental exposures, we compared the frequency of respiratory symptoms, pulmonary function, quality of life, exercise capacity, and computed tomography phenotypes.
Thirty-one subjects (8.9%) had history of living near factory, 271 (78.3%) had exposure history to briquette, and 184 (53.3%) had exposure history to firewood. Patients with history of living near a factory had a significantly longer duration of sputum, while patients with exposure to firewood tended to have lower forced expiratory volume in one second, and patients with exposure to briquette tended to have lower six minute walk distance.
COPD subjects with the history of living near factory had more frequent respiratory symptoms such as sputum. Our data suggest that environmental exposure may influence clinical phenotype of COPD.
Tuberculosis and Respiratory Diseases 05/2014; 76(5):226-32. DOI:10.4046/trd.2014.76.5.226
[Show abstract][Hide abstract] ABSTRACT: Background
The Korean Obstructive Lung Disease (KOLD) Cohort Study is a prospective longitudinal study of patients with chronic obstructive pulmonary disease (COPD), asthma, or other unclassified obstructive lung diseases. It was designed to develop new classification models and biomarkers that predict clinically relevant outcomes for patients with obstructive lung diseases.
Patients over 18 years old who have chronic respiratory symptoms and airflow limitations or bronchial hyper-responsiveness were enrolled at 17 centers in South Korea. After a baseline visit, the subjects were followed up every 3 months for various assessments.
From June 2005 to October 2013, a total of 477 subjects (433 [91%] males; 381 [80%] diagnosed with COPD) were enrolled. Analyses of the KOLD Cohort Study identified distinct phenotypes in patients with COPD, and predictors of therapeutic responses and exacerbations as well as the factors related to pulmonary hypertension in COPD. In addition, several genotypes were associated with radiological phenotypes and therapeutic responses among Korean COPD patients.
The KOLD Cohort Study is one of the leading long-term prospective longitudinal studies investigating heterogeneity of the COPD and is expected to provide new insights for pathogenesis and the long-term progression of COPD.
Tuberculosis and Respiratory Diseases 04/2014; 76(4):169. DOI:10.4046/trd.2014.76.4.169
[Show abstract][Hide abstract] ABSTRACT: Spirometric measurements of pulmonary function are important in diagnosing and determining the severity of chronic obstructive pulmonary disease (COPD). We performed this study to determine whether candidate genes identified in genome-wide association studies of spirometric measurements were associated with COPD and if they interacted with smoking intensity.
The current analysis included 1,000 COPD subjects and 1,000 controls recruited from 24 hospital-based pulmonary clinics. Thirteen SNPs, chosen based on genome-wide association studies of spirometric measurements in the Korean population cohorts, were genotyped. Genetic association tests were performed, adjusting for age, sex, and smoking intensity, using models including a SNP-by-smoking interaction term.
PID1 and FAM13A were significantly associated with COPD susceptibility. There were also significant interactions between SNPs in ACN9 and FAM13A and smoking pack-years, and an association of ACN9 with COPD in the lowest smoking tertile. The risk allele of FAM13A was associated with increased expression of FAM13A in the lung.
We have validated associations of FAM13A and PID1 with COPD. ACN9 showed significant interaction with smoking and is a potential candidate gene for COPD. Significant associations of genetic variants of FAM13A with gene expression levels suggest that the associated loci may act as genetic regulatory elements for FAM13A gene expression.
Beiträge zur Klinik der Tuberkulose 04/2014; 192(4). DOI:10.1007/s00408-014-9579-4 · 2.27 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background
We aimed to identify the 1-year relapse rate and risk factors for patients with pulmonary tuberculosis (TB) treated with a 6-month daily regimen.
A total of 317 patients with pan-susceptible pulmonary TB who completed a 6-month daily course of treatment [2HRZ(E)/4HR(E)] were retrospectively analyzed.
The mean age was 50.0±16.8 years and men were predominant (61.2%). All of 137 adults tested for HIV were negative. Six (1.9%) cases relapsed within one year. Relapse rate was higher in patients with a positive culture after 2 months of treatment (10.0%, p = 0.049) and in patients with both a positive culture after 2 months of treatment and cavitation on initial chest radiograph (18.2%, p = 0.015), whereas relapse rate in patients with cavitation alone was comparable to that of the total population (2.7%). Among various risk factors known to increase risk of relapse, the combined variable of cavitation and positive culture at 2 months (OR=15.56, 95% CI 2.56-98.71, p = 0.003) was only associated with increased relapse rate in a multivariate analysis.
Even with a 6-month daily treatment regimen throughout the intensive and continuation phases, the relapse rate was unacceptably high in patients with both a positive culture at 2 months of treatment and cavitation on baseline chest radiography. Intensification of treatment, such as an extension of treatment duration, should be considered in this category of patients.
Respiratory medicine 04/2014; 108(4). DOI:10.1016/j.rmed.2014.01.010 · 3.09 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We aimed to investigate the results of anti-tumor necrosis factor (TNF) therapy in patients with a previous history of tuberculosis (TB).
A total of 101 patients with a previous history of TB receiving TNF antagonists between December 2004 and September 2012 at the Asan Medical Center in South Korea were retrospectively analyzed.
The mean age of the 101 subjects was 40.4 ± 16.0 years and 51 patients (50.5%) were male. The underlying immune-mediated inflammatory diseases (IMIDs) were Crohn's disease in 55 (54.5%), rheumatoid arthritis in 27 (26.7%), and ankylosing spondylitis in 13 (12.9%) patients. Chest radiography findings were suggestive of previous TB lesions in 33 (32.7%) patients. The rates of positivity in the tuberculin skin test and interferon-gamma release assay were 21.8% (22/101) and 44.6% (45/101), respectively. Latent TB infection (LTBI) treatment was initiated in 11 subjects (10.9%) based on previous inappropriate anti-TB treatments (n = 10) or recent TB contact history (n = 1), irrespective of the LTBI test results. The median follow-up duration after the initiation of TNF antagonist therapy was 31.5 months. Active TB developed, six years after the initiation of TNF antagonist, in one patient (1.0%) who had not received LTBI treatment. The incidence rate of TB was calculated at 336 per 100,000 person-year (PY).
Patients with IMIDs who have a previous history of TB can be treated with TNF antagonists with an acceptable incidence of TB, if LTBI treatment is performed based on clinical judgments including the adequacy of previous anti-TB treatment and recent contact history.
Respiratory medicine 08/2013; 107(11). DOI:10.1016/j.rmed.2013.08.011 · 3.09 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Extracorporeal membrane oxygenation (ECMO) is useful for providing hypoxic patients with ventilatory support, but its usefulness in the management of patients with central airway obstruction has rarely been reported. Nineteen cases in one center where venovenous (VV) ECMO was used to support patients with severe central airway obstruction while they underwent lifesaving interventions are reported here.
In total, 113 cases of VV ECMO were performed in Asan Medical Center between January 2009 and June 2012. In 19 cases (18 patients), VV ECMO was used to support patients with severe airway obstruction.
Of the 18 patients, 13 were male, and their median age was 62.5 (range, 16-82) years. The main reasons for using ECMO to provide airway security were malignant mass removal with a rigid bronchoscope (8 cases) and insertion of a tracheal stent (7 cases). The median ECMO time was 20.9 (range, 2.2-113.4) hours. In 1 case, a patient died of massive bleeding after a malignant mass was removed. Weaning off ECMO therapy occurred successfully in the remaining 18 cases.
Venovenous ECMO may be useful in patients with central airway obstruction because it provides short-term airway security while lifesaving procedures are being performed.
Journal of critical care 07/2013; 28(5). DOI:10.1016/j.jcrc.2013.05.020 · 2.00 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We investigated the prevalence of latent tuberculosis infection (LTBI) among the health care workers (HCWs) and analyzed its risk factors in South Korea.
A standard questionnaire regarding the baseline demographics and risk factors for LTBI was given to each participant and tuberculin skin test (TST), QuantiFERON-TB GOLD In-Tube (QFT-GIT) assay, and chest radiography were performed.
A total of 493 participants, 152 (30.8%) doctors and 341 (69.2%) nurses were enrolled in eight tertiary referral hospitals. The mean age of the subjects was 30.6 years old, and 383 (77.7%) were female. Of the 152 doctors, 63 (41.4%) and 36 (23.7%) were positive by TST and by QTF-GIT, respectively, and among the 341 nurses, 119 (34.9%) and 49 (14.4%) had positive TST and QFT-GIT results, respectively. Overall, the agreement between the two tests was 0.22 by the chance corrected proportional agreement rate (kappa coefficient) in 493 subjects. Experience of working in tuberculosis (TB)-related departments was significantly associated with positive LTBI test results by QFT-GIT assay, not by TST. In multivariate analysis, only age was independently associated with increased risk of a positive TST result, while age and experience of working in TB-related departments (odds ratio, 2.29; 95% confidence interval, 1.01-5.12) were independently associated with increased risk of a positive QFT-GIT result.
A high prevalence of LTBI was found among South Korean HCWs. Considering the association between the experience of working in TB-related departments and high risk of LTBI, QFT-GIT may be a better diagnostic test for LTBI than TST in HCWs.
Tuberculosis and Respiratory Diseases 07/2013; 75(1):18-24. DOI:10.4046/trd.2013.75.1.18
[Show abstract][Hide abstract] ABSTRACT: Non-tuberculosis mycobacteria (NTM) have emerged as an important pathogen in lung infection. NTM infection is rarely accompanied by pleural involvement, and empyema necessitatis caused by NTM is very uncommon. We report a very rare case of Mycobacterium abscessus pulmonary disease with empyema accompanied by empyema necessitatis. The patient was successfully treated by percutaneous tube drainage of the empyema and empyema necessitatis with aggressive antibiotics treatment and surgical resection.
Respiratory Medicine Case Reports 12/2012; 6:1-4. DOI:10.1016/j.rmcr.2012.06.001
[Show abstract][Hide abstract] ABSTRACT: Objective:
We investigated the efficacy of rifabutin (RFB)-containing regimens for the treatment of RFB-susceptible, multidrug-resistant tuberculosis (MDR-TB).
From 146 patients diagnosed with MDR-TB between January 2006 and December 2009 at Asan Medical Center in South Korea, 31 patients (21.2%) were found to have RFB-susceptible MDR-TB. Of these 31 patients, 14 patients who had been treated with RFB for more than one month were included. Forty-two patients with RFB-resistant MDR-TB were selected as a control group, and the outcomes of both groups were retrospectively compared.
Of 14 patients with RFB-susceptible MDR-TB, the mean age was 44.4 years and the proportion of extensively drug-resistant TB (XDR-TB) was 35.7% (5/14). Baseline characteristics and the drug resistance pattern (except RFB) did not differ between the two groups. Treatment success was achieved in 12 (85.7%) patients in the RFB group: cure in 10 (71.4%) and treatment completion in two (14.3%). The treatment success rate was 52.4% (22/42) in the control group (p = 0.032). Treatment failure was more common in patients of the control group (40.5% vs. 14.3%; p = 0.106).
RFB is useful as an additional drug in the treatment of MDR-TB in patients with RFB-susceptible MDR-TB.
Respiratory medicine 11/2012; 107(2). DOI:10.1016/j.rmed.2012.10.021 · 3.09 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Chronic obstructive pulmonary disease (COPD) is a spectrum of various syndromes that share airflow limitation but differ in many respects. Although airflow limitation is a defining element of COPD, forced expiratory volume in 1 s (FEV1) alone is not sufficient to explain the heterogeneity of COPD. Phenotypic characterization of clinically relevant subgroups of COPD will increase our understanding of COPD. Furthermore, a greater understanding of the complex interrelationships between the phenotypes and their environmental, genetic, molecular, and cellular basis may be achieved with comprehensive and integrated method (systems biology and network medicine). Incorporation of information obtained from these analyses into our clinical practice would allow clinicians to treat individual patients with so-called Personalized, Predictive, Preventive, and Participatory (P4) medicine. By understanding COPD heterogeneity, it may be possible in the future to detect the disease earlier and to target treatment to reduce mortality and modify the course of the disease.