• Tuberculosis and Respiratory Diseases
• /
• v.39 no.4
• /
• pp.304-309
• /
• 1992

Background: The alveolar macrophage may metabolize arachidonic acid through cyclooxygenase- and lipoxygenase- catalyzed pathways to produce a variety of metabolites of arachidonic acid. The production of these metabolites of arachidonic acid may enhance the defensive ability of the challenged lung. However, continued stimulation with the consequent production of proinflammtory metabolites of arachidonic acid, may ultimately enhance the disease process by contributing to chronic bronchoconstriction, fibrosis, and the persistent release of toxic oxygen species. Silicosis is an example of a disease process resulting from chronic exposure of the lung to foreign particles. This study was carried out to evaluate the changes of arachidonic acid metabolites from macrophages in experimental silicosis. Methods: We measured $PGE_2$, and $LTB_4$ in cultured macrophages taken from rats by radioimmunoassay at 24 and 48 hours after stimulation by silica dust, natural carbon dust, lipopolysaccharide, calcium ionophore (A23187) and medium (RPMI) as a control. For the experimental silicosis, 50 mg silica in 0.5 ml saline was administered intratracheally into the rat and grown to 20 weeks and measured $PGE_2$, and $LTB_4$ in the cultured macrophages lavaged from that rat. The used stimulants were the same as above. Results: 1) The amount of $PGE_2$ in the cultred macrophages from normal rat was significantly decreased in the group which was stimulated with silica dust for 48 hours compare with control non-stimulated group. 2) In the experimental silicosis group, $PGE_2$, release in cultured macrophages after 48 hours incubation with silica and natural carbon dust tended to be lower than those of non-stimulated group. 3) There were marked changes of $LTB_4$ in the groups of normal rats which were incubated with silica for 24, 48 hours and natural carbon for 48 hours compared with non-stimulated group. 4) In the experimental silicosis group, the release of $LTB_4$ was significantly increased macrophages cultured with silica and natural carbon dust after 24 and 48 hours incubation compared with non-stimulated group. Conclusion: The results of these studies suggest that the in vitro exposure of rat alveolar macrophge to silica and coal dust results in an alteration in alveolar macrophage metabolism of arachidonic acid that may promote an inflammatory reaction in lung tissue.

• Tuberculosis and Respiratory Diseases
• /
• v.41 no.5
• /
• pp.513-520
• /
• 1994

Background: The pathogenesis of silicosis has been focused on the interaction between alveolar macrophages and silica particle. Although fibrosis in silicosis has been studied extensively, the mechanism is still not fully understood. There is increasing evidence that monokines and arachidonic acid metabolites macrophage are involved in pathogenesis of silicosis. Recently, it was reported that prostaglandin E2 produced from macrophage counteracts the stimulatory effects of other monokines on fibroblast proliferation or collagen production. Until now, it was remained uncertain by which mechanism silica particle may activate alveolar macrophage to an enhanced release of prostaglandin E2. Methods: In order to investigate the relationship between the activity of alveolar macrophage and the production of $PGE_2$ from activated alveolar macrophage, the authors measured hydrogen peroxide and $PGE_2$ from alveolar macrophages activated by silica in vitro and from alveolar macrophages in the silicotic nodules from rat. Experimental silicosis was induced by intratracheal infusion of silica($SiO_2$) suspended in saline(50 mg/ml) in Sprague-Dawley rats. Results: produced by 1) The silicotic nodules with fibrosis were seen from the sections of rat lung at 60 days after intratracheal injection with 50 mg aqueous suspension of silica(Fig. 1). 2) In vitro, silica caused the dose dependent increase of hydrogen peroxide(p<0.05, Fig. 2A) and $PGE_2$(p>0.05, Fig. 2B) release from alveolar macrophages. Alveolar macrophages from rat with silicotic nodules released more hydrogen peroxide and $PGE_2$ than those of control group(p<0.05, Fig. 3). Conclusion: These results suggest that silica particle could activate macrophage directly and enhanced the release of $PGE_2$ and hydrogen peroxide from the alveolar macrophage.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.29 no.4
• /
• pp.582-589
• /
• 2019

Objectives: Although active pulmonary tuberculosis(active PTB) is manifested as one of the complications of pneumoconiosis, attacks of active PTB among patients with pneumoconiosis is still unexplored. The objective of the present study was to identify the attack rate of active PTB among workers in dusty environments who were diagnosed with pneumoconiosis. Methods: The study was performed using the results of the Pneumoconiosis Examination Council's assessment from the Korea Workers' Compensation and Welfare Service(KCOMWEL) database between January 1, 1984 and December 31, 2017. Pneumoconiosis was defined as Category 1 or more in the radiological findings of pneumoconiosis. Active PTB was defined as a positive result for active PTB in the results of the Pneumoconiosis Examination Council's assessment. Results: A total of 37,946 workers in dusty environments who received a health examination for diagnosing pneumoconiosis between January 1, 1984 and December 31, 2017 were selected as study subjects. The attack rate of active TB among subjects who were diagnosed with pneumoconiosis and those who were diagnosed without pneumoconiosis were 8.5% and 1.4%, respectively. In the multivariate logistic analysis including age, sex, radiological findings, complications, male[odds ratio(OR), 2.0; 95% confidence interval(CI), 1.4-3.1] and pneumoconiosis(OR, 6.5; 95% CI, 5.7-7.4) were associated with an increased risk of developing active PTB. Conclusions: The present study determined that dusty workers who were diagnosed with pneumoconiosis had a high rate of active PTB compared to TB patients and patients who were diagnosed with silicosis. Therefore, in addition to silicosis, it is necessary to include pneumoconiosis among the high-risk groups for TB.

• Tuberculosis and Respiratory Diseases
• /
• v.45 no.2
• /
• pp.437-443
• /
• 1998

Pulmonary alveolar proteinosis is characterized by the accumulation of PAS positive lipoproteinaceous or amorphous proteinaceous material in the alveolar space with spared delicate septal architecture of the lung interstitium and impaired gas exchange of alveoli. We experienced a case of secondary pulmonary alveolar proteinosis in a 41 year old male patient who have occupational history of engagement as a mason over 4year. He compalined exertional dyspnea and chest discomfort, and presented fine inspiratory crackle at both lower lung field, numerous fine nodular denisties in both lung field with peripheral sparing. Light microscopic finding of lung tissue obtained by transbronchiallung biopsy revealed homogenous eosinophilic colloid-like luminal content in the alveolar space, and electron microscopy of bronchoalveolar lavage fluid concentrate showed electron-dense multilamellated structures. To treat the disease, we tried whole lung lavage of right lung with isotonic saline under general anesthesia. After whole lung lavage of right lung, he showed markid improvement of symptom and partial improvement of chest X-ray findings. The patient has been followed for 12 month until now, with no evidence of aggravation.

• Journal of Chest Surgery
• /
• v.19 no.2
• /
• pp.259-264
• /
• 1986

Broncholithiasis is defined as a cor9ition in which a concretion is present within a bronchus or a cavity in the lung communicating with a bronchus. The usual causes of broncholithiasis are known as tuberculosis, histoplasmosis, silicosis, aspirated calculi, and a few fungal infections. It is generally accepted that the constant motion created by respiration and beating of the heart may cause the peribronchial calcified lymph node to erode into the tracheobronchial tree and to form broncholith. After the analysis of our 6 cases of broncholithiasis which were treated surgically in the Department of Thoracic Surgery, Seoul National University Hospital from 1960 to December, 1985, we could suggest that intrinsic formation of calculi should be regarded as the pathogenesis of broncholithiasis in addition to the extrinsic formation of calculi.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.10
• /
• pp.4883-4888
• /
• 2012

In materials science, one of the new concerns in the construction industry, it is well established that mineral dust from rocks (stones) has adverse effects on human health. For instance, it is suspected that some mineral dusts in particular leads to occupational diseases, including lung cancer. The present research concerned the relationship between cancer and those workers who work in Turkish construction industry and quarries and are exposed to silica mineral dust from natural stones. One focus was cancer prevention methods applied in-site. In mining and construction industry where stone dust is widely used, silicosis induced lung cancer is frequently seen. Cancer cases which are seen across the regions mostly affected by silica containing dust in Turkey were identified and a survey was conducted of the methods to protect workers in the construction industry from exposure to silica dust.

• Korean Journal of Radiology
• /
• v.24 no.8
• /
• pp.795-806
• /
• 2023

Occupational lung diseases (OLD) are a group of preventable conditions caused by noxious inhalation exposure in the workplace. Workers in various industries are at a higher risk of developing OLD. Despite regulations contributing to a decreased incidence, OLD remain among the most frequently diagnosed work-related conditions, contributing to significant morbidity and mortality. A multidisciplinary discussion (MDD) is necessary for a timely diagnosis. Imaging, particularly computed tomography, plays a central role in diagnosing OLD and excluding other inhalational lung diseases. OLD can be broadly classified into fibrotic and non-fibrotic forms. Imaging reflects variable degrees of inflammation and fibrosis involving the airways, parenchyma, and pleura. Common manifestations include classical pneumoconioses, chronic granulomatous diseases (CGD), and small and large airway diseases. Imaging is influenced by the type of inciting exposure. The findings of airway disease may be subtle or solely uncovered upon expiration. High-resolution chest CT, including expiratory-phase imaging, should be performed in all patients with suspected OLD. Radiologists should familiarize themselves with these imaging features to improve diagnostic accuracy.

• The Korean Journal of Nuclear Medicine
• /
• v.33 no.4
• /
• pp.381-387
• /
• 1999

Purpose: The International Labor Organization (ILO) has established an international standard for chest X-ray diagnosis of pneumoconiosis since 1980. However, there is a need for improved diagnosis and staging in occupational disease. We evaluated Ga-67 citrate scintigraphy quantitatively and correlated the scintigraphic findings with pulmonary function tests and chest X-ray results. Materials and Methods: Twenty-five patients underwent whole body scintigraphy with additional chest and abdomen images 48 hrs after intravenous injection of 185 MBq of Ga-67 citrate. Ten normal controls were also studied. Regions of interest (ROI) were drawn on the posterior image to measure counts from the liver and lungs (Lung/Liver Ratio). Results: L/L ratio according to the stages of chest X-ray classification were as follows; stage 0 (normal, n=10): $0.3948{\pm}0.0692$, stage 1 (n=10): $0.5763{\pm}0.1537$, stage 2 (n=11), $0.6849{\pm}0.1459$, stage 3 (n=4) $0.9913{\pm}0.0712$. There was a significant correlation between the scintigraphic L/L ratio and the X-ray stage (r=0.618, p<0.05). However, no significant correlation between L/L ratio and pulmonary function tests were observed (p>0.05). Conclusion: Quantitative Ga-67 scintigraphy can be a useful method for staging of silicosis. However, it is not a method to assess pulmonary functional impairment.

• Journal of Environmental Health Sciences
• /
• v.9 no.2
• /
• pp.19-30
• /
• 1983

This report is intended to find out the health status of the korean industrial workers based on the periodic physical examination in 1982. It has resulted in the followings: 1. As of April, 1982, total No. of industries was 81,136 of which workers was totally 3,383,700 persons classifying into 2,163,600 in male and 1,220,100 in female, and manufacturing field was occupied 44.6% of total industries and 61.0% of total workers. 2. In view of size, industries having less than 9 ordinary workers was 47.5%, those having less than 29 ordinary workers was 77.0%. 3. Applicable target industries to industrial safety & health law was 31,059 which was covered 38.3% of total establishments and No. of workers was 2,192,511, 64.8% of all industrial workers. 4. No. of establishment & workers conducting the physical examination was 26,463 which is 85.2% of all examining industries and was 2,007,091, 91.5% of all examining required workers. 5. Case having general disease by general physical examination was 3.5% of examining workers and especially it was appeared 9.7% in mining. 6. Case having general disease by special physical examination was 3.8% of examining workers and incidence rate for occupational disease was 2.4% of examining workers. 7. No. of the occupational diseased was 5,341 persons which is 2.6% of all the examining workers, 205,497 and its rate was appeared highly as 7.5% of silicosis in mining workers and 1.4% of hearing difficulty to noise in construction.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.7 no.1
• /
• pp.153-165
• /
• 1997

This study investigated the current industrial hygiene status of China, a socialistic country, to explore the future direction of industrial hygiene of in Korea. In China, the industrial hygiene is called as labor hygiene, which includes industrial health and industrial hygiene. The main goal of labor hygiene is to protect the health of laborers, promote the productivity and ensure the development of industry and agriculture. Started since the foundation of People's Republic of China in 1949, the labor hygiene developed with the occupational disease science which belongs to clinical medicine, has grown today as an independent science. The labor hygiene has made a rapid progress, especially for the last 20 years. The scope of industrial hygiene was expanded from the prevention and treatment of silicosis to pneumoconiosis and o.ther occupational poisoning caused toxic substances. In addition, not only the prevention of industrial toxication but also the prevention of hazards of phisical causes were included in the scope of industrial hygiene. Based on activation of health centers, the organization for the prevention & treatment of occupational diseases was established at the city, county and state. The industrial hygiene monitoring is being carried out through clear division and partition system.