• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.3
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• pp.404-413
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• 2019

Objectives: Chronic obstructive pulmonary disease(COPD) is an important cause of mortality in workers exposed to hazardous dust, such as crystalline silica or coal, and COPD is related to inflammation and oxidative stress in the lung. The aim of this study was to evaluate the association of oxidative stress and inflammation to COPD in retired workers exposed to mineral dust. Methods: The levels of malondialdehyde(MDA) in EBC as biomarkers for oxidative stress and C-reactive protein(CRP) and lactate dehydrogenase(LD) as biomarkers for inflammation were measured in 107 male subjects(63 pneumoconiosis and 42 COPD subjects). Results: Mean levels of EBC MDA(2.03 nmol/L vs. 4.65 nmol/L, p=0.010) and serum LD(170.3 U/L vs. 185.9 U/L, p=0.022) were significantly higher in subjects with COPD, but mean levels of serum CRP(p=0.469) did not show a statistical difference between the study groups. Level of EBC MDA was negatively correlated with ${%}FEV_1$ predicted(r=-0.279, p=0.004) and ${%}FEV_1/FVC$ ratio(r=-0.397, p<0.001). Conclusions: These results suggest that EBC is a useful biological matrix for investigation of respiratory oxidative stress. High levels of EBC MDA and serum LD are related to COPD in retired workers exposed to mineral dust.

• Tuberculosis and Respiratory Diseases
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• v.39 no.1
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• pp.28-34
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• 1992

Background: Diffuse panbronchiolitis (DPB) is a chronic obstructive pulmonary disease distinguished from bronchial asthma, chronic bronchitis, pulmonary emphysema, bronchiectasis, or alveolitis. It is prevalent in Japan, but is known to be rare outside of Japan. Only a few cases in Chinese, Italian, Noirth American and Korean have been reported. During recent two years we have found 16 cases of DPB in Seoul National University Hospital and analyzed the clinical characteristics. Method: We reviewed the patients' age, sex, duration of illness, smoking history, occupational history and past medical history. And we analyzed patients' symptoms, physical signs, laboratory findings and responses to treatment. Results: 1) Male: female ratio was 2.2:1, the ages ranged from 27 to 72 years old, and the duration of disease varied from 1 to 20 years. 2) Most of the patients were being treated as bronchiectasis, miliary tuberculosis, chronic bronchitis or bronchial asthma before they were diagnosed as DPB. 3) Only one patient was a smoker, and 25% of patients had the occupational history of exposure to particles or gas. And all patients had paranasal sinusitis. 4) High resolution computed tomography (HRCT) was very useful in diagnosing the disease in most of the patients. 5) PFT showed obstructive and restrictive abnormalities, and blood gas revealed hypoxemia in most of the patients. 6) Pseudomonas aeruginosa was isolated in the sputum of four patients (25%). 7) The titers of cold hemaglutinin, RA factor and CRP were elevated in most of the patients. 8) Most of the patients improved after treatment with erythromycin. Conclusion: DPB might not be a rare disease in Korea. So DPB should be suspected in a patient who has chronic cough, sputum, dyspnea and diffuse fine nodular chest X-ray abnormality. HRCT and open lung biopsy should be considered in a patient suspected of DPB.

• Tuberculosis and Respiratory Diseases
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• v.76 no.5
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• pp.226-232
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• 2014

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.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.34 no.1
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• pp.57-66
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• 2024

Objective: Chronic obstructive pulmonary disease (COPD) is characterized by progressive airflow obstruction that is only partly reversible, inflammation in the airways, and systemic effects. This study aimed to investigate the association between low peripheral oxygen saturation levels (SpO₂), and composite indices predicting death in male patients with (COPD). Method: A total of 140 participants with post-bronchodilator FEV₁/FVC ratio less than 0.7 were included. Three composite indices (ADO, DOSE, BODEx) were calculated using six variables such as age (A), airflow obstruction (O), body mass index (B), dyspnea (D), exacerbation history (E or Ex), and smoking status (S). Severity of airflow limitation was classified according to Global Initiative for Obstructive Lung Disease (GOLD) guidelines. SpO₂ was measured by pulse oximetry, and anemia and iron deficiency were assessed based on blood hemoglobin levels and serum markers such as ferritin, transferrin saturation, or soluble transferrin receptor. Results: Participants with low SpO₂ (<95%) showed significantly lower levels of %FEV₁ predicted (p=0.020) and %FEV₁/FVC ratio (p=0.002) compared to those with normal SpO₂ levels. The mMRC dyspnea scale (p<0.001) and GOLD grade (p=0.002) showed a significant increase in the low SpO₂ group. Receiver Operating Characteristic analysis revealed higher area under the curve for %FEV₁ (p=0.020), %FEV₁/FVC(p=0.002), mMRC dyspnea scale (p=0.001), GOLD grade (p=0.010), ADO (p=0.004), DOSE (p=0.002), and BODEx (p=0.011) in the low SpO₂ group. Conclusion: These results suggest that low SpO₂ levels are related to increased airflow limitation and the composite indices of COPD.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.31 no.3
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• pp.286-293
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• 2021

Objectives: Inorganic dust is known to be a risk factor for chronic obstructive pulmonary disease (COPD) regardless of smoking and pneumoconiosis. Adaptive and innate immunity, including lymphocyte infiltrate, are involved in the pathogenesis of COPD. The purpose of this study was to analyze the lymphocyte subsets in the blood of workers exposed to inorganic dust and confirm the influencing factors. Methods: The general characteristics of the subjects (n=107) were analyzed through a personal questionnaire. Diagnosis of COPD was established according to pulmonary function tests with FEV₁/FVC post bronchodilator lower than 70%, according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines. For lymphocyte analysis, blood was stained with a fluorescent CD marker and analyzed by flow cytometry. Results: The increase in CD4⁺ T lymphocytes was associated with a decrease in age (𝛽=-0.273, p=0.008) and an increase in the cumulative smoking amount (𝛽=0.205, p=0.034). The increase in NK cells was associated with an increase in age (𝛽=0.325, p=0.001) and a decrease in cumulative smoking (𝛽=-0.220, p=0.019). The period of exposure to dust, %FVC predicted and %FEV₁/FVC, and the relative population of peripheral blood lymphocytes did not show a statistically significant relationship. Conclusions: CD4⁺ T lymphocytes and CD56⁺CD16⁺ NK cells in peripheral blood were more related to age and cumulative smoking than the duration of dust exposure. Age and smoking are major risk factors for the development of COPD, so it can be predicted that peripheral blood CD4⁺ T lymphocytes and CD56⁺CD16⁺ NK cells are related to the development of COPD in workers exposed to inorganic dust.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.1
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• pp.42-49
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• 2019

Objective: Chronic obstructive pulmonary disease(COPD) is characterized by persistent airflow limitations associated with chronic inflammatory response due to noxious particles or gases in the lung. Iron deficiency is associated with chronic inflammation, such as COPD. The aim of this study was to evaluate the relationship among iron deficiency, iron homeostasis, and inflammation in retired miners with COPD. Methods: The serum levels of ferritin, soluble transferrin receptor(sTfR), and transferrin saturation(TSat) as biomarkers for iron deficiency and high-sensitivity C-reactive protein(hsCRP) as a biomarker for inflammation and hepcidin as a biomarker for iron homeostasis were measured in 93 male subjects. Iron deficiency was defined as any one or more of (1) sTfR>28.1 nmol/L, (2) TSat<16%, and (3) ferritin< $12{\mu}g/L$. Results: Iron deficiency was found 28% of the study subjects. Median levels of serum hsCRP was significantly increased related to airflow limitation of COPD(GOLD 1, $0.09{\mu}g/dL$ vs. GOLD 2, $0.17{\mu}g/dL$ vs. GOLD $3{\leq}$, $0.30{\mu}g/dL$, p=0.010), and was positively correlated with hepcidin(p=0.009). Mean level of serum hepcidin was lower in COPD subjects with iron deficiency(p=0.004) and serum levels of hepcidin was negatively correlated with %$FEV_1$ predicted(p=0.030). Conclusions: These results suggest that high serum levels of hepcidin are related to severe airflow limitation or inflammation and can decrease iron availability, regardless of iron status.

• The Korean Journal of Physiology
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• v.30 no.1
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• pp.77-83
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• 1996

Platelet-activating factor(PAF) is a phospholipid mediator of pulmonary inflammation, and immunologic reaction. In this study, the role of PAF on tumor necrosis factor$(TNF_{-{\alpha}})$ production by rat alveolar macrophages(AM) was examined. When PAF $(10^{-12}{\sim}10{-16}\;M)$ alone was added to AM culture, $(TNF_{-{\alpha}})$ production was not significantly increased above the resting level. In contrast, the combined addition of PAF $(10^{-6}\;M)$ and muramyl dipeptide(MDP) $(1.0\;{\mu}g\ml)$ to AM cultures markedly enhanced $(TNF_{-{\alpha}})$ production with 8.2 fold increase compared with AM culture in resting state. This potentiative effect was 313% above the sum of the separate effects of PAF and MDP. To characterize MDP effects on $(TNF_{-{\alpha}})$ production, the dose-response of AM cultured with various concentrations of MDP was tested. High level of MDP $(10\;{\mu}g\ml)$ could not significantly enhance the potentiation effect on $(TNF_{-{\alpha}})$ production compared with AM cultures with low level of MDP $(0.1\;{\mu}g\ml)$, i.e. 112.5% vs 107.8%, respectively when $10^{-10}$ M of PAF was simultaneously added to the cell culture. These data support that the potentiation of TNF. g production in AM culture is mediated by PAF rather than MDf It was also evaluated whether the similar result was obtained in silica, respirable toxic particle-treated AM culture. $(TNF_{-{\alpha}})$ production was also significantly enhanced in the PAF $(10^{-6}\;M)$ and silica $(50\;{\mu}g\ml)$-added cell cultures with 4.7 fold above the value of silica alone-stimulated cells. These results indicate that PAF can potentiate $(TNF_{-{\alpha}})$ production by MDP-or silica- stimulated AM and suggest that PAF may play a potent role in lung inflammation and disease associated with microbe and occupational dust exposures.

• Tuberculosis and Respiratory Diseases
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• v.64 no.3
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• pp.210-214
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• 2008

Chemical pneumonitis is an occupational lung disease that's caused by the inhalation of chemical substances. Its severity depends on the characteristics of the substances, the exposure time and the susceptibility of the patients. Hydrogen sulfide is not only emitted naturally, but it also frequently found in industrial settings where it is either used as a reactant or it is a by-product of manufacturing or industrial processes. Inhalation of hydrogen sulfide causes various respiratory reactions from cough to acute respiratory failure, depending on the severity. Two pharmaceutical factory workers were admitted after being rescued from a waste water disposal site that contained hydrogen sulfide. In spite that they recovered their consciousness, they had excessive cough and mild dyspnea. The simple chest radiographs and high resolution computed tomography showed diffuse interstitial infiltrates, and hypoxemia was present. They were diagnosed as suffering from chemical pneumonitis caused by hydrogen sulfide. After conservative management that included oxygen therapy, their symptoms, hypoxemia and radiographic abnormalities were improved.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.3
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• pp.245-256
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• 2017

Objectives: The present study is aimed at performing real-time measurement of fibrous materials using an F-1 fiber monitor, investigating the correlations between the measurements and environmental conditions, and assessing the feasibility of the use of the monitor in actual exposure assessments based on the accuracy and reliability of the device. Methods: Asbestos specimens with a fixed asbestos content were dispersed in a chamber and collected with a particle measuring test device. Measurements obtained by the existing PCM method, and with the F-1 fiber monitor were compared. In addition, concentrations of asbestos fibers obtained by the PCM method, the TEM method, and the F-1 fiber monitor were compared with that of specific ABS scenarios in NOA regions. Correlations of asbestos contents in soil and weather conditions with each method of measurement were analyzed. Results: Laboratory results showed that levels of asbestos fibers measured with each method increased as fiber contents in soil increased. In the accuracy and reproducibility assessment, no significant differences were found between the different methods of measurement. On-site assessment results showed positive correlations among the methods, and these correlations were less significant compared with what was shown by the laboratory results. Levels of asbestos fibers increased as asbestos contents in soil increased, and as temperature increased. Levels of asbestos fibers decreased as humidity increased, and wind speed did not significantly affect the extent to which asbestos fibers were scattered. Conclusions: While it would be premature to replace existing methods with the use of F-1 fiber monitors in real sites based on the results of this study, the monitor may be useful in the screening of the sites, which assesses hazard levels in different regions. Replacement of existing methods with the use of F-1 fiber monitors may be possible after the limitations identified in this study are overcome, and additional assessment data are obtained and reviewed under different conditions to confirm the reliability of the monitor in future research. Obtained assessment results may be used as basic data for the assessment of asbestos hazard in NOA regions.

• Tuberculosis and Respiratory Diseases
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• v.84 no.4
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• pp.263-273
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• 2021

Cough is the most common respiratory symptom that can have various causes. It is a major clinical problem that can reduce a patient's quality of life. Thus, clinical guidelines for the treatment of cough were established in 2014 by the cough guideline committee under the Korean Academy of Tuberculosis and Respiratory Diseases. From October 2018 to July 2020, cough guidelines were revised by members of the committee based on the first guidelines. The purpose of these guidelines is to help clinicians efficiently diagnose and treat patients with cough. This article highlights the recommendations and summary of the revised Korean cough guidelines. It includes a revised algorithm for the evaluation of acute, subacute, and chronic cough. For a chronic cough, upper airway cough syndrome (UACS), cough variant asthma (CVA), and gastroesophageal reflux disease (GERD) should be considered in differential diagnoses. If UACS is suspected, first-generation antihistamines and nasal decongestants can be used empirically. In cases with CVA, inhaled corticosteroids are recommended to improve cough. In patients with suspected chronic cough due to symptomatic GERD, proton pump inhibitors are recommended. Chronic bronchitis, bronchiectasis, bronchiolitis, lung cancer, aspiration, intake of angiotensin-converting enzyme inhibitor, intake of dipeptidyl peptidase-4 inhibitor, habitual cough, psychogenic cough, interstitial lung disease, environmental and occupational factors, tuberculosis, obstructive sleep apnea, peritoneal dialysis, and unexplained cough can also be considered as causes of a chronic cough. Chronic cough due to laryngeal dysfunction syndrome has been newly added to the guidelines.