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. METHODS: 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. RESULTS: 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). CONCLUSION: 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.
Asian Continental Ancestry Group* ; Asthma ; Dust* ; Gangwon-do ; Humans ; Korea ; National Health Programs ; Pulmonary Disease, Chronic Obstructive ; Respiratory System ; Retrospective Studies ; Weather*

The earliest stages of mammalian embryogenesis are governed by the activity of maternally inherited transcripts and proteins. Cytoplasmic polyadenylation of selected maternal mRNA has been reported to be a major control mechanism of delayed translation during preimplantation embryogenesis in mice. The presence of cis-elements required for cytoplasmic polyadenylation (e.g., CPE) can serve as a useful tag in the screening of maternal genes partaking in key functions in the transcriptionally dormant egg and early embryo. However, due to its relative simplicity, UA-rich sequences satisfying the canonical rule of known CPE consensus sequences are often found in the 3'-UTR of maternal transcripts that do not actually undergo cytoplasmic polyadenylation. In this study, we developed a method to confirm the validity of candidate CPE sequences in a given gene by a multiplex comparison of 3'-UTR sequences between mammalian homologs. We found that genes undergoing cytoplasmic polyadenylation tend to create a conserved block around the CPE, while CPE-like sequences in the 3'-UTR of genes lacking cytoplasmic polyadenylation do not exhibit such conservation between species. Through this cross-species comparison, we also identified an alternative CPE in the 3'-UTR of tissue-type plasminogen activator (tPA), which is more likely to serve as a functional element. We suggest that verification of CPEs based on sequence conservation can provide a convenient tool for mass screening of factors governing the earliest processes of mammalian embryogenesis.
Animals ; Consensus Sequence ; Cytoplasm ; Embryonic Development ; Embryonic Structures ; Female ; Mass Screening ; Mice ; Ovum ; Polyadenylation ; Pregnancy ; RNA, Messenger, Stored ; Tissue Plasminogen Activator

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is sometimes complicated with pneumonia, but little is known about the risk factors that promote the development of pneumonia in COPD. These risk factors were evaluated in the present study. METHODS: The data of 324 patients with COPD from a prospective multi-center observational cohort with obstructive lung disease were evaluated retrospectively. To identify risk factors for the development of pneumonia in COPD, the clinical and radiological data at enrollment and the time to the first episode of pneumonia were analyzed by Cox proportional hazard analysis. RESULTS: The median follow-up time was 1,099 days and 28 patients (8.6%) developed pneumonia. The Cox analysis showed that post-bronchodilator forced expiratory volume in one second (FEV1, % of predicted) and the computed tomography (CT) emphysema extent (inspiratory V950) were independent risk factors for the development of pneumonia (post-bronchodilator FEV1: hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.94-1.00; p=0.048 and inspiratory V950: HR, 1.04; 95% CI, 1.01-1.07; p=0.01). CONCLUSION: Emphysema severity measured by CT and post-bronchodilator FEV1 are important risk factors for the development of pneumonia in COPD.
Cohort Studies ; Emphysema* ; Follow-Up Studies ; Forced Expiratory Volume ; Humans ; Lung Diseases, Obstructive ; Lung* ; Pneumonia* ; Prospective Studies ; Pulmonary Disease, Chronic Obstructive* ; Retrospective Studies ; Risk Factors ; Tomography, X-Ray Computed

BACKGROUND: Lung cancer is the most common cause of cancer-related mortality worldwide. We previously reported the identification of a new genetic marker, cellular retinoic acid binding protein 2 (CRABP2), in lung cancer tissues. The aim of this study was to assess plasma levels of CRABP2 from patients with non-small cell lung cancer (NSCLC). METHODS: Blood samples that were collected from 122 patients with NSCLC between September 2009 and September 2013 were selected for the analysis, along with samples from age- (± 5 years), sex-, and cigarette smoking history (± 10 pack-years [PY])-matched controls from the Korea Biobank Network. The control specimens were from patients who were without malignancies or pulmonary diseases. We measured plasma levels of CRABP2 using commercially available enzyme-linked immunosorbent assay kits. RESULTS: The mean age of the NSCLC patients was 71.8 ± 8.9 years, and the median cigarette smoking history was 32 PY (range, 0–150 PY). Plasma CRABP2 levels were significantly higher in patients with NSCLC than in the matched controls (37.63 ± 28.71 ng/mL vs. 24.09 ± 21.09 ng/mL, P < 0.001). Higher plasma CRABP2 levels were also correlated with lower survival rates in NSCLC patients (P = 0.014). CONCLUSION: Plasma CRABP2 levels might be a novel diagnostic and prognostic marker in NSCLC.
Biomarkers ; Carcinoma, Non-Small-Cell Lung* ; Carrier Proteins ; Enzyme-Linked Immunosorbent Assay ; Genetic Markers ; Humans ; Korea ; Lung Diseases ; Lung Neoplasms ; Mortality ; Plasma* ; Smoking ; Survival Rate ; Tretinoin

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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.
Air Pollutants ; Environmental Exposure* ; Forced Expiratory Volume ; Fossil Fuels ; Humans ; Korea ; Lung Diseases, Obstructive ; Occupational Exposure ; Phenotype ; Pulmonary Disease, Chronic Obstructive* ; Quality of Life ; Risk Factors ; Smoking ; Sputum

BACKGROUND: Park et al. developed the Korean reference equation for the measurement of diffusing capacity in 1985. However, the equation has not been widely used in Korea and foreign reference equations have been popularly used. We intended to compare the clinical usefulness and the accuracy of the the Korean reference equation (Park's equation) with that of the foreign equation (Burrows' equation) that is commonly used in Korea. METHODS: 1. Evaluation of clinical usefulness; Among 1,584 patients who underwent diffusing capacity (D(L)CO) at the Asan Medical Center from July to December 2006, group A subjects included 276 patients who had different interpretations of D(L)CO in trials employing Burrows' equation and Park's equation. Clinical assessment was decided by consensus of two respiratory physicians. In order to evaluate the clinical usefulness of Burrows' equation and Park's equation, agreement of clinical assessment and DLCO interpretation were measured. 2. Evaluation of accuracy; Group B subjects were 81 patients with interstitial lung disease (ILD) and 39 normal subjects. The 81 ILD patients were diagnosed following a surgical lung biopsy. The accuracy of diagnosing ILD as well as sensitivity and specificity were evaluated according to the use of the reference equations (Burrows' equation and Park's equation) for DLCO. RESULTS: Agreement between clinical assessment and interpretation of D(L)CO was 22% for the use of Burrows' equation and 78% for the use of Park's equation. The sensitivity and specificity of the Burrows' equation for diagnosing ILD were 64.2% and 100%. The sensitivity and specificity of the Park's equation for diagnosing ILD were 90.1% and 100%. The sensitivity of the Park's equation for diagnosing ILD was significantly higher than that of Burrows' equation (p<0.001). CONCLUSION: The Korean reference equation (Park's equation) was more clinically useful and had higher sensitivity for diagnosing ILD than the foreign reference equation (Burrows' equation).
Biopsy ; Consensus ; Humans ; Korea ; Lung ; Lung Diseases, Interstitial

BACKGROUND: Although airway obstruction in chronic obstructive pulmonary disease (COPD) is due to pathologic processes in both the airways and the lung parenchyma, the contribution of these processes, as well as other factors, have not yet been evaluated quantitatively. We therefore quantitatively evaluated the factors contributing to airflow limitation in patients with COPD. METHODS: The 213 COPD patients were aged >45 years, had smoked >10 pack-years of cigarettes, and had a post-bronchodilator forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) <0.7. All patients were evaluated by medical interviews, physical examination, spirometry, bronchodilator reversibility tests, lung volume, and 6-minute walk tests. In addition, volumetric computed tomography (CT) was performed to evaluate airway wall thickness, emphysema severity, and mean lung density ratio at full expiration and inspiration. Multiple linear regression analysis was performed to identify the variables independently associated with FEV1 - the index of the severity of airflow limitation. RESULTS: Multiple linear regression analysis showed that CT measurements of mean lung density ratio (standardized coefficient beta=-0.46; p<0.001), emphysema severity (volume fraction of the lung less than -950 HU at full inspiration; beta=-0.24; p<0.001), and airway wall thickness (mean wall area %; beta=-0.19, p=0.001), as well as current smoking status (beta=-0.14; p=0.009) were independent contributors to FEV1. CONCLUSION: Mean lung density ratio, emphysema severity, and airway wall thickness evaluated by volumetric CT and smoking status could independently contribute to the severity of airflow limitation in patients with COPD.
Aged ; Airway Obstruction ; Cone-Beam Computed Tomography ; Emphysema ; Forced Expiratory Volume ; Humans ; Linear Models ; Lung ; Pathologic Processes ; Physical Examination ; Pulmonary Disease, Chronic Obstructive ; Smoke ; Smoking ; Spirometry ; Tobacco Products ; Tomography, X-Ray Computed ; Vital Capacity

To date, clinico-physiologic indices have not been compared with quantitative CT imaging indices in determining the risk of chronic obstructive pulmonary disease (COPD) exacerbation. We therefore compared clinico-physiologic and CT imaging indices as risk factors for COPD exacerbation in patients with COPD. We retrospectively analyzed 260 COPD patients from pulmonary clinics at 11 hospitals in Korea from June 2005 to November 2009 and followed-up for at least one year. At the time of enrollment, none of these patients had COPD exacerbations for at least 2 months. All underwent clinico-physiologic and radiological evaluation for risk factors of COPD exacerbation. After 1 yr, 106 of the 260 patients had at least one exacerbation of COPD. Multiple logistic regression analysis showed that old age, high Charlson Index, and low FEV1 were significant in a clinico-physiologic model, with C-statistics of 0.69, and that increased age and emphysema index were significant in a radiologic model, with C-statistics of 0.64. The difference between the two models was statistically significant (P = 0.04 by bootstrap analysis). Combinations of clinico-physiologic risk factors may be better than those of imaging risk factors in predicting COPD exacerbation.
Aged ; Aged, 80 and over ; Disease Progression ; Female ; Humans ; Male ; Middle Aged ; Pulmonary Disease, Chronic Obstructive/*diagnosis/pathology/*physiopathology ; Retrospective Studies ; Risk Factors ; Severity of Illness Index ; *Tomography, X-Ray Computed