• Tuberculosis and Respiratory Diseases
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• v.48 no.3
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• pp.331-338
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• 2000

Background : While the incidence of lung cancer is gradually leveling off in developed countries, it is continuing to rise in Korea. With the rapid increase in the prevalence of smoking among women and the young, the incidence of lung cancer is also expected to increase within the next three and four decades. The aims of the present study are to analyze the smoking habits in patients with lung cancer and to evaluate of the relative risk of lung cancer according to patients' smoking habits. Method : This investigation was a hospital-based, case control study, which included data of 93 case subjects with lung cancer and 1132 controls with disease unrelated to smoking, obtained through a smoking history questionnaire by a direct personal interview. Result : Compared with non-smokers, those who smoked for more than 50 years had an odds ratio for lung cancer of 8.8(1.8-20.7). The odds ratios was 8.5(3.5-20.7) for those who smoke more than a total of 40 cigarettes per day and 5.5(2.3-13.3) for men who started habitual smoking under the age of 20. The risk increased for men with more than of cigarette smoking(OR : 5.5, 95% CIa : 2.6-11.9). Odds ratios associated with cigarette smoking were 2.5(1.1-5.8) and 5.1(2.6-10.4) for ex-smokers and current smokers, respectively and 2.2(0.0-4.6) for non-filter smokers of more than 16 years. Conclusion : There was a clear dose-response relationship between the risk of lung cancer and smoking. It can be concluded that dose is an important risk factor for lung cancer, as well as smoking habits.

• Tuberculosis and Respiratory Diseases
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• v.53 no.2
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• pp.173-182
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• 2002

Background : Nontuberculous mycobacteria (NTM) have usually been considered to be contaminants of colonizers when isolated from respiratory specimens in Korea, where there is a high prevalence of tuberculosis and a low rate of HIV infections. Therefore, there has been few studies on the clinical significance of NTM species in immunocompetent patients were investigated. Methods : Thirty-five NTM isolates, for which species identification was requested by the treating physicians during 1999 at the Asan Medical Center, were retrospectively analyzed. They were identified to the species level by mycolic acid analysis using high-performance liquid chromatography. The medical records of the patients with the NTM isolates were reviewed to identify those patients who met the American Thoracic Society (ATS)'s criteria for mycobacterial pulmonary infection. Their antimicrobial susceptibility data were compared with the clinical outcomes. Results : The NTM were identified as M. intracellulare (6 isolates), M. avium (5), M. abscessus (5), M. gordonae (5), M. terrae complex (4), M. szulgai (2), M. kansasii (2), M. fortuitum (2), M. peregrinum (1), M. mucogenicum (1), M. celatum (1), and M. chelonae (1). All 35 patients showed clinical symptoms and signs of chronic lung disease, but none had a HIV infections; 16 (45.7%) patients were found to be compatible with a NTM pulmonary infection according to the ATS criteria, 5 and 4 cases were affected with M. intracellulare and M. abscessus, respectively; 8 patients had a history of pulmonary tuberculosis. 13 patients received antimycobacterial therapy for an average of 21 months and 9 patients were treated with second-line drugs. Only 4 patients had improved radiologically. Conclusion : A NTM should be considered a potential pathogen of pulmonary infections in immunocompetent patients with chronic pulmonary diseases. Most NTM infections were left untreated for a prolonged period and showed a poor outcome as a result, M. intracellulare and M. abscessus were the two most frequent causes of NTM pulmonary infections in this study. Species identification and antimycobacterial susceptibility tests based on the species are needed for the optimum management of a NTM pulmonary infection in patients.

• Tuberculosis and Respiratory Diseases
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• v.46 no.6
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• pp.846-855
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• 1999

Background : Secondary pulmonary hypertension is an important final endpoint in patients with chronic hypoxic lung disease, accompanied by deterioration of pulmonary hemodynamics. The clinical diagnosis of pulmonary hypertension and/or cor pulmonale could be difficult, and simple noninvasive evaluation of pulmonary artery pressures has been an relevant clinical challenge for many years. Doppler echocardiography might to be a more reliable method for evaluating pulmonary hemodynamics in such patients in terms of the accuracy, reproducibility and easiness for obtaining an appropriate echocardiographic window than M-mode echocardiography. The aim of this study was to assess echocardiographic parameters associated with pulmonary arterial hypertension, defined by increasing right ventricular systolic pressure(RVSP), calculated from trans-tricuspid gradient in patients with chronic hypoxic lungs. Method : We examined 19 patients with chronic hypoxic lung disease, suspected pulmonary hypertension under the clinical guidelines by two dimensional echocardiography via the left parasternal and subcostal approach in a supine position. Doppler echocardiography measured RVSP from tricuspid regurgitant velocity in continuous wave with 2.5MHz transducer and acceleration time(AT) on right ventricular outflow tract in pulsed wave for the estimation of pulmonary arterial pressure. Results : On echocardiography, moderate to severe degree of pulmonary arterial hypertension was defined as RVSP more than 40mmHg, presenting tricuspid regurgitation. Increased right ventricular endsystolic diameter and shortened AT were noted in the increased RVSP group. Increased RVSP was correlated negatively with the shortening of AT. Other clinical data, including pulmonary functional parameters, arterial blood gas analysis and M mode echocardiographic parameters were not changed significantly with the increased RVSP. Conclusion : These findings suggest that shortened AT on pulsed doppler can be useful when quantifying pulmonary arterial pressure with increased RVSP in patients with chronic lung disease with hypoxemia. Doppler echocardiography in pulmonary hypertension of chronic hypoxic lungs is an useful option, based on noninvasiveness under routine clinical practice.

• Tuberculosis and Respiratory Diseases
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• v.51 no.5
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• pp.409-415
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• 2001

Background : Multidrug-resistant tuberculosis(MDR-TB) in patients is mainly caused by acquired drug resistance. However, a small proportion of MDR-TB is caused by initial drug resistance(IDR), which may be somewhat different from acquired drug resistance. This study analyzed the clinical characteristics of IDR in MDR -TB patients to use the results as basic data in managing the disease. Methods : A retrospective study of 30 IDR cases in MDR-TB patients from Jan. 1995 to Dec. 1998 was performed. In order to analyze the clinical characteristics, the age, sex, family history, duration of negative conversion, number of resistant drugs, treatment regimens, duration of treatment, extent of disease and cavitary lesion on the chest X-ray was examined. In order to analyze the level of improvement, the extent of the disease and cavitary lesion on the chest X-ray, tested by Wilcoxon signed rank sum test, and the disease free interval rate of 1-year and 4-year was examined using the Kaplan-Meier method. Results : The mean age of the patients was 46.6 years and the sex ratio 1:1. Six(20%) patients had a family history. The mean negative conversion of the sputum AFB stain was 2.6 months. The number of resistant drugs was 7.6 and the number of used drugs 3.6. Twenty-three(67%) patients were treated for less than 12months and 28(93%) patients were treated with first-line drugs. The extent of the disease and the cavitary lesion on the chest X-ray improved after treatment(p<.05). Among 13 patients who were followed up for 22.6 months, 2(15%) patients relapsed and the disease free interval rate of I-year and 4-year was 85%. Conclusion: It is recommended that the duration of treatment of IDR in MDR-TB with first-line drugs be 9-12 months even if the extent of disease and cavitary lesion on the chest X-ray improves.

• Tuberculosis and Respiratory Diseases
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• v.51 no.5
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• pp.426-436
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• 2001

Objective : This study was performed to determine the smoking status and its associated factors in military life among young Korean men to provide data for smoking prevention in military areas as a part of the health promotion program for soldiers. Methods : 1,033 infantrymen serving in 17 military units, which are located in suburbs of K city, were enrolled in this study. A questionnaire on the soldiers smoking status and other various characteristics was obtained from October 2nd to 12th, 2000. Logistic regression analysis was performed on the various variables in order to determine the factors related to smoking. Results : 1) 830(80.3%) out of 1033 subjects had smoked cigarettes and 759 persons(73.4%) were regular smokers. 2) Among the 734 soldiers who started smoking before their military service, 714 soldiers(97.2%) continued to smoke after, while 45 soldiers(15.0%) among the 299 non-smokers started smoking after joining the army. 3) Through the logistic regression analysis. the education level. specialty in the army. smoking amongst the friends they met before military service, smoking amongst soldiers in the army. dating girl friends, drinking, satisfaction with their army lives and the presence of convenient smoking places at the barracks were significant factors related to the prevalence of smoking in soldiers. Conclusion : The factors related with incidence of smoking in the army are the complicated interactions among the individuals personal background, general characteristics of the soldier and the special environment in the barracks. Therefore, to improve national soldiers' health, an active non-smoking campaign and education should be pushed to discourage smoking in the barracks.

• Tuberculosis and Respiratory Diseases
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• v.50 no.2
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• pp.205-212
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• 2001

Background : The information on nasal transport and the metabolism of peptides have been obtained from pharmacokinetic investigations in experimental animals. However, there are no transport and metabolic studies of human nasal epithelial cells. In this study, the permeability characteristics and the metabolic properties of in vitro human nasal cell monolayers were investigated. Material and Methods : Normal human inferior nasal conchal tissue samples were obtained from patients undergoing endoscopic nasal cavitary surgery. The specimens were cultured in a transwell using an air-liquid Interface (ALI) culture, and the transepithelial electrical resistance (TEER) value of the blank filter and confluent cell monolayers were measured. To determine the % leakage of mannitol, $4{\mu}mol%$ $^{14}C$-labelled mannitol was added and the % leakage was measured every 10 minute for 1 hour. Result : Human nasal epithelial cells in the primary culture grew to a confluent monolayer within 7 days and expressed microvilli. The tight junction between the cells was confirmed by transmission electron microscopy. The TEER value of the blank filter, fifth day and seventh day reached $108.5\;ohm.cm^2$, $141\;ohm.cm^2$ and $177.5\;ohm.cm^2$, respectively. Transcellular % leakage of the $^{14}$-mannitol at 10, 20, 30, 40, 50 and 60 minutes was $35.67{\pm}5.43$, $34.42{\pm}5.60$, $32.75{\pm}5.71$, $31.76{\pm}4.22$, $30.96{\pm}3.49$ and $29.60{\pm}3.68\;%$, respectively. Conclusion : The human nasal epithelial monolayer using ALI culture techniques is suitable for a transcellular permeability study. The data suggests that human nasal epithelial cells In an ALI culture technique shows some promise for a nasal transport and metabolism study.

• Tuberculosis and Respiratory Diseases
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• v.50 no.4
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• pp.409-414
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• 2001

Background : Legionella pneumophila has been recognized as an important cause of community-acquired pneumonia(CAP) requiring hospitalization. However, epidemiological data on the occurrence of legionella-related pneumonia is unavailable in Korea. The purpose of this study was to evaluate the etiological importance of legionella pneumophila serogroup 1 in patients hospitalized with CAP. Method : The CAP patients over 16 year-old were recruited from July 1999 to June 2000 at the Chunchon Sacred Heart Hospital. Fifty four patients (male 29, female 25, average age $63.8{\pm}15.3$) were included in this study. A diagnosis of a legionella pneumophila infection was based on a urinary antigen test using the Binax Company enzyme immunoassay. The severity of pneumonia was assessed using the Fine's PORT scoring system. Result : The average Fine's PORT score was 99.7(${\pm}44.9$). According to the risk classification proposed by the Infectious Disease Society of America, the number of patients in each class(from class I to class V) were 6(11.1%), 13(24.1%), 9(16.7%), 14(25.8%), and 12(22.2%), respectively. Thirty two patients(59.3%) were initially admitted to the intensive care unit. The mortality rate was 16.7%(9 in 54). In all patients, urinary antigens to Legionella pnewnophila serogroup 1 were not detected. Conclusion : Legionella pnewnophila may play little role in causing adult CAP in Korea. Therefore, the routine use of macrolide in the empirical treatment of the CAP patients based upon the ATS guidelines(1993) in Korea should be reevaluated.

• Tuberculosis and Respiratory Diseases
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• v.48 no.3
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• pp.365-376
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• 2000

Background : Ever since Flexible Fiberoptic Bronchoscopy was introduced into clinical practice, it has played an important role in both diagnosis and therapy of respiratory diseases. Repeated bronchoscopic examinations is are not so uncommon. This study was designed prospectively to assess the clinical availability of the Repeated Flexible Bronchoscopy (RFB). Methods : Pre-established indications were as follows : 1) To confirm diagnosis or the cell type in proven malignancy 2) to diagnose or locate hemoptysis 3) to follow-up or confirm recurrence 4) to use in therapy. We performed RFB and analyzed the data in 156 patients during 28-month period. Results : The frequency of RFB was 23.0%. The indication for diagnosis or cell type of malignancy was 25 cases, of which 2 cases were confirmed by a third bronchoscopic examination and 3 cases by surgical procedures. Localization of the bleeding site was confirmed in 53.8%. RFB for small cell lung cancer yielded more information on residual or recurred lesion not apparent even with the CT scan in 30%. Previous cases of bronchostenosis due to endo-bronchial tuberculosis was shown to have worsened in 66.7%. Therapeutic manipulations were done in 126 cases, and bronchial suction was most common. Complications showed decreasing tendency with repeated examinations. Conclusion : The RFB for diagnosis or cell type of malignancy was useful in that comfirmation of diagnosis was possible in 85.7% of malignancy. More aggressive procedures should be employed including TBLB or TBNA. The RFB showed possible usefulness in the follow-up of patients with small cell lung cancer. For the patients with hemoptysis or endobronchial tuberculosis, the RFB did not the significance did not show significance because its results did not influence the diagnosis, therapy or clinical course.

• Tuberculosis and Respiratory Diseases
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• v.48 no.3
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• pp.347-356
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• 2000

Background : Patients with obstructive sleep apnea syndrome are known to have high long-term mortality compared to healthy subjects because of their cardiovascular dysfunction. The observation of hemodynamic changes by obstructive apneas is helpful when attempting to understand the pathophysiological mechanism of the development of cardiovascular dysfunction in those patients. Therefore, we studied the changes in cardiovascular function with an animal model and tried to obtain the basic data for an ideal experimental model (this phrase is unclear), a requirement for a more advanced study. Methods : Sixteen anesthetized dogs with ${\alpha}$-chloralose delete were divided into two groups : 8 dogs of room air breathing group and 8 dogs of oxygen breathing group. We measured $PaO_2$, $PaCO_2$, heart rate, cardiac output, mean femoral artery pressure, and mean pulmonary artery pressure at specified times during the apnea-breathing cycle before endotracheal tube occlusion (baseline), 25 seconds after endotracheal tube occlusion (apneic period), 10 seconds (early phase of postapneic period, EPA) and 25 seconds (late phase of postapneic period, LPA) after spontaneous breathing. Results : In room air breathing group, the heart rate significantly decreased during the apneic period compared to that at baseline (P<0.01) and increased at EPA and LPA compared to that during the apneic period (P<0.01). But, the heart rate showed no significant changes during apneic and postapneic periods in the oxygen breathing group. Cardiac output tended to decrease during apneic period compared to that at baseline, but was statistically significant. Cardiac output significantly decreased at LP A compared to at baseline (P<0.01). Mean femoral artery pressure was significantly decreased at during apneic period compared to that at baseline (P<0.05). Conclusion : Through this experiment, we were partially able to understand the changes of cardiovascular function indirectly, but delete new experimental animal model displaying physiological mechanism close to natural sleep should be established, and the advanced study in the changes of cardiovascular function and their causes should be continued.

• Tuberculosis and Respiratory Diseases
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• v.55 no.5
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• pp.478-487
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• 2003

Background : There have been several studies showing that the angiotensin II and angiotensin converting enzyme(ACE) contributes to the apoptosis of alveolar epithelial cells in idiopathic interstitial pneumonia and the activation of fibroblasts during the process of pulmonary fibrosis. These results suggest that the pulmonary fibrosis can be inhibited by the angiotensin II receptor antagonist(AGIIRA). This study was performed to identify the therapeutic effect of AGIIRA in idiopathic pulmonary fibrosis(IPF). Method : Thirteen patients with IPF, who were diagnosed with an open lung biopsy(6 patients) and furfilling the ATS criteria(7 patients) between March 1999 and October 2001 at the Gachon medical center, were enrolled in this study. Of these patients, eight patients were treated with a regimen including AGIIRA(AT group), and five were treated without AGIIRA(NT group). The pulmonary function tests and dyspnea(ATS scale) were measured at diagnosis and 1 year after treatment. All the data was collected to analyze the therapeutic effect of AGIIRA on the patients with IPF. Results : The AT group contained 8 patients(M:F=4:4) and the NT group contained 5 patients(M:F=3:2). There was no significant difference in the serum angiotensin II level between the two groups($202.5{\pm}58.5$ vs $163.7{\pm}47.3pg/ml$, p>0.05). The AT group showed an upward trend in TLC(+3%), FVC(+4%), FEV1(+3%) and DLco(+2%) compared to the NT group(TLC(-14%), FVC(-3%), FEV1(-4%) except for DLco(+5%)). The dyspnea score in the AT group improved significantly but not in the NT group. Conclusion : These results suggest that the angiotensin II receptor antagonist may have an effect on stabilizing IPF.