• Tuberculosis and Respiratory Diseases
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• v.55 no.3
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• pp.267-279
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• 2003

Background : The purpose of this study was to analyze the smoking habits in patients with lung cancer and identify any difference of prevalence according to histologic types of lung cancer. Methods : The data were calculated by total amounts of tar and nicotine inhaled during the whole lifetime according to variation of smoking habit. This study was to investigated any difference of prevalence in lung cancer according to smoking habits. The subjects comprised 150 lung cancer cases and 300 hospital control cases that were matched by age and sex. Smoking habits during the whole lifetime were surveyed by standardized questionnaire. Odds ratios were estimated by unconditional logistic regression analysis. Results : There were 104 male and 34 female lung cancer cases. By histologic type, there were 53 cases of squamous cell carcinoma, 67 of adenocarcinoma and 30 of small cell lung carcinoma. The differences between lung cancer cases and controls according to smoking habits were total duration of smoking, total pack years of smoking and number of cigarettes smoked per day during the previous two years. The odds ratio were higher in Kreyberg I, but not in Kreyberg II, for the longer duration of smoking, the greater total pack years of cigarettes consumed, the more cigarettes smoked per day during the previous two years, the longer duration on non-filter smoking, the earlier life cases who began to smoke, and the higher amounts of calculated total tar and nicotine inhaled over the whole lifetime. When we added grade of inhalation to calculation of amounts of tar and nicotine inhaled over the lifetime, the odds ratios of total inhalation amounts of tar and nicotine were as high as those the without them. Conclusions : This study reconfirmed that smoking habits were strongly associated with lung cancer and that there were different associations between smoking habits and histologic types of lung cancer. In particular, calculations of total tar and nicotine amounts inhaled over the whole lifetime were calculated for the first time in trials from lung cancer epidemiologic studies.

• Tuberculosis and Respiratory Diseases
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• v.60 no.6
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• pp.625-630
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• 2006

Background: Pulmonary hypertension in COPD patients is the result of a direct effect of tobacco smoke on the intrapulmonary vessels with the abnormal production of the mediators that control vasoconstriction, vasodilatation, and vascular cell proliferation, which ultimately lead to aberrant vascular remodeling and physiology. COPD patients are prone to the developmint of an acute and chronic thromboembolism with an elevation of the plasma procoagulant and fibrinolytic markers However, the roles of the coagulation and fibrinolysis system on the right ventricular dysfunction in COPD patients are not well defined. We examined the alteration of the coagulation and fibrinolysis system in COPD patients according to the right ventricular function measured using cardiac multidetector computed tomography (MDCT). Methods: The right ventricular ejection fraction (RVEF) was measured using cardiac MDCT in 26 patients who were diagnosed with COPD according to the definition of the GOLD guideline. The plasma level of thrombin antithrombin (TAT) and plasminogen activator inhibitor (PAI)-1 were measured using an enzyme linked immunoassay. Results: The plasma TAT was markedly elevated in COPD patients ($10.5{\pm}19.8{\mu}g/L$) compared with those of the control ($3.4{\pm}2.5{\mu}g/L$) (p<0.01). However, the plasma PAI-1 in COPD patients ($29.6{\pm}20.7ng/mL$) was similar to that in the controls. The plasma TAT showed a significant inverse relationship with the RVEF measured by the cardiac MDCT in COPD patients (r=-0.645, p<0.01). However, the plasma PAI-1 did not show a relationship with the RVEF (r=0.022, p=0.92). Conclusion: These results suggest that the coagulation system in COPD patients is markedly activated, and that the plasma level of TAT might be a marker of a right ventricular dysfunction in COPD patients.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.6
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• pp.256-268
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• 2016

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2015. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering were carried out in the areas of flow, heat and mass transfer, cooling and heating, and air-conditioning, the renewable energy system and the flow inside building rooms. Research issues dealing with air-conditioning machines and fire and exhausting smoke were reduced. CFD seems to be spreading to more research areas. (2) Research works on heat transfer area were carried out in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the economic analysis of GHG emission, micro channel heat exchanger, effect of rib angle on thermal performance, the airside performance of fin-and-tube heat exchangers, theoretical analysis of a rotary heat exchanger, heat exchanger in a cryogenic environment, the performance of a cross-flow-type, indirect evaporative cooler made of paper/plastic film. In the area of pool boiling and condensing, the bubble jet loop heat pipe was studied. In the area of industrial heat exchangers, researches were performed on fin-tube heat exchanger, KSTAR PFC and vacuum vessel at baking phase, the performance of small-sized dehumidification rotor, design of gas-injection port of an asymmetric scroll compressor, effect of slot discharge-angle change on exhaust efficiency of range hood system with air curtain. (3) In the field of refrigeration, various studies were carried in the categories of refrigeration cycle, alternative refrigeration/energy system, system control. In the refrigeration cycle category, a cold-climate heat pump system, $CO_2$ cascade systems, ejector cycles and a PCM-based continuous heating system were investigated. In the alternative refrigeration/energy system category, a polymer adsorption heat pump, an alcohol absorption heat pump and a desiccant-based hybrid refrigeration system were investigated. In the system control category, turbo-refrigerator capacity controls and an absorption chiller fault diagnostics were investigated. (4) In building mechanical system research fields, eighteen studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, and renewable energies, piping in the buildings. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the user and location awareness technology applied dimming lighting control system, the lighting performance evaluation for light-shelves, the improvement evaluation of air quality through analysis of ventilation efficiency and the evaluation of airtightness of sliding and LS window systems. The subjects of building energy were worked on the energy saving estimation of existing buildings, the developing model to predict heating energy usage in domestic city area and the performance evaluation of cooling applied with economizer control. The studies were also performed related to the experimental measurement of weight variation and thermal conductivity in polyurethane foam, the development of flame spread prevention system for sandwich panels, the utilization of heat from waste-incineration facility in large-scale horticultural facilities.

• Tuberculosis and Respiratory Diseases
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• v.50 no.4
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• pp.426-436
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• 2001

Background : Chronic obstructive pulmonary disease(COPD) is one of the major contributors to morbidity and mortality among the adult population. Cigarette smoking(CS) is undoubtedly the single most important factor in the pathogenesis of COPD. However, its mechanism is unclear. The current hypothesis regarding the pathogenesis of COPD postulates that an imbalance between proteases and antiproteases leads to the destructive changes in the lung parenchyma. This study had two aims. First, to evaluate the effect of CS exposure on histologic changes of the lung parenchyme, and second, to evaluate the effect of CS exposure on the expression of the gelatinolytic enzymes in BAL fluid cells in guinea pigs. Methods : Two groups of five guinea pigs were exposed to the whole smoke of 20 commercial cigarettes per day, 5 hours/day, 5 days/week, for 6weeks, and 12 weeks, respectively, using a smoking apparatus. Five age-matched guinea pigs exposed to room air were used as controls. Five or more sections were microscopically extamined(${\times}400$) and the number of cellular infiltration of the alveolar wall was measured in order to evaluate the effect of CS exposure on the histologic changes of lung parenchyme. The statistical significance was analyzed by a linear regression method. To evaluate the expression of the gelatinolytic enzymes in intraalveolar cells, BAL fluid was obtained and the intraalveolar cells were separated by centrifugation (500 g for 10 min at $4^{\circ}C$). Two sets of culture plates were loaded with $1{\times}10^6$ intraalveolar cells. One plate, contained O.1mM EDTA, a inhibitor of matrix metalloproteases(MMPs), and the other plate had no EDTA. Both plates were incubated for 48 hours at $37^{\circ}C$. After incubation, gelatinolytic protease expression in the supernatants was analyzed by gelatin zymography. Results : At the end of CS exposure, the level of blood carboxy Hb had increased significantly(4.1g/dl in control group, 24g/dl immediately after CS exposure, 18g/dl 30 min after CS exposure, 15g/dl 1 hour after CS exposure). Alveolar inflammatory cells were identified in the CS exposed guinea pigs. The number of alveolar cellular cells observed in a microscopic field ($400{\times}$) was $121.4{\pm}7.2$, $158.0{\pm}20.2$, $196.8{\pm}32.8$, in the control, the 6 weeks, and the 12 weeks group, respectively. The increased extent of inflammatory cellular infiltration of the lung parenchema showed a statistically significant linear relationship with the duration of CS exposure(p=0.001, $r^2=0.675$). Several types of gelatinolytic enzymes in the intraalveolar cells of CS exposed guinea pigs were expressed, of which some were inhibited by EDT A. However, the gelatinolytic enzymes were not expressed in the control groups. Conclusion : CS exposure increases inflammatory cellular infiltration of the alveolar wall and the expression of gelatinolytic proteases in guinea pigs. EDTA inhibits some of the gelatinolytic proteases. These findings suggest a possibility that CS exposure may increase MMP expression in the lungs of guinea pigs.