• Tuberculosis and Respiratory Diseases
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• v.79 no.4
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• pp.257-266
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• 2016

Background: Idiopathic pulmonary fibrosis is a common interstitial lung disease; it is a chronic, progressive, and fatal lung disease of unknown etiology. Over the last two decades, knowledge about the underlying mechanisms of pulmonary fibrosis has improved markedly and facilitated the identification of potential targets for novel therapies. However, despite the large number of antifibrotic drugs being described in experimental pre-clinical studies, the translation of these findings into clinical practices has not been accomplished yet. NADH:quinone oxidoreductase 1 (NQO1) is a homodimeric enzyme that catalyzes the oxidation of NADH to $NAD^+$ by various quinones and thereby elevates the intracellular $NAD^+$ levels. In this study, we examined the effect of increase in cellular $NAD^+$ levels on bleomycin-induced lung fibrosis in mice. Methods: C57BL/6 mice were treated with intratracheal instillation of bleomycin. The mice were orally administered with ${\beta}$-lapachone from 3 days before exposure to bleomycin to 1-3 weeks after exposure to bleomycin. Bronchoalveolar lavage fluid (BALF) was collected for analyzing the infiltration of immune cells. In vitro, A549 cells were treated with transforming growth factor ${\beta}1$ (TGF-${\beta}1$) and ${\beta}$-lapachone to analyze the extracellular matrix (ECM) and epithelial-mesenchymal transition (EMT). Results: ${\beta}$-Lapachone strongly attenuated bleomycin-induced lung inflammation and fibrosis, characterized by histological staining, infiltrated immune cells in BALF, inflammatory cytokines, fibrotic score, and TGF-${\beta}1$, ${\alpha}$-smooth muscle actin accumulation. In addition, ${\beta}$-lapachone showed a protective role in TGF-${\beta}1$-induced ECM expression and EMT in A549 cells. Conclusion: Our results suggest that ${\beta}$-lapachone can protect against bleomycin-induced lung inflammation and fibrosis in mice and TGF-${\beta}1$-induced EMT in vitro, by elevating the $NAD^+$/NADH ratio through NQO1 activation.

• Journal of Chest Surgery
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• v.24 no.4
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• pp.338-344
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• 1991

If the postoperative pulmonary function can be predicted in the patients undergoing pneumonectomy for lung cancer preoperatively, it will be helpful for identifying them as high or low risk candidates. Perfusion lung scan and spirometry were performed in 12 patients with lung cancer pre-operatively and the predicted postoperative Vital Capacity, FVC, FEV1.0, FEF25 - 75% and MVV were estimated by multiplying the preoperative values by the percentage of perfusion of the nonsurgical lung. Three months postoperation the patients were reinvestigated with spirometry and the obtained values were compared with the predicted values. The linear regression lines derived from the correlation between predicted values [X] and observed values [Y] were as follows; VC; R=0.532, Y=0.48X+1.28, P=0.075 FVC; R=0.566, Y=O 54X+1.15, P=0.055 FEV1.0; R=0.832, Y=0.68X+0.70, P=0.001 FEF25 ~ 75%; R=0.781, Y=0.68X+0.54, P=0.003 MVV; R=0.718, Y=0.67X+34.75, P=0.009 The prediction of postoperative FEV1.0, FEF25 ~ 75% and MVV in lung cancer patients undergoing pneumonectomy appear to be valid for evaluating preoperative pulmonary function.

• Tuberculosis and Respiratory Diseases
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• v.86 no.3
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• pp.203-215
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• 2023

Background: Surgical resection is the standard treatment for early-stage lung cancer. Since postoperative lung function is related to mortality, predicted postoperative lung function is used to determine the treatment modality. The aim of this study was to evaluate the predictive performance of linear regression and machine learning models. Methods: We extracted data from the Clinical Data Warehouse and developed three sets: set I, the linear regression model; set II, machine learning models omitting the missing data: and set III, machine learning models imputing the missing data. Six machine learning models, the least absolute shrinkage and selection operator (LASSO), Ridge regression, ElasticNet, Random Forest, eXtreme gradient boosting (XGBoost), and the light gradient boosting machine (LightGBM) were implemented. The forced expiratory volume in 1 second measured 6 months after surgery was defined as the outcome. Five-fold cross-validation was performed for hyperparameter tuning of the machine learning models. The dataset was split into training and test datasets at a 70:30 ratio. Implementation was done after dataset splitting in set III. Predictive performance was evaluated by R² and mean squared error (MSE) in the three sets. Results: A total of 1,487 patients were included in sets I and III and 896 patients were included in set II. In set I, the R² value was 0.27 and in set II, LightGBM was the best model with the highest R² value of 0.5 and the lowest MSE of 154.95. In set III, LightGBM was the best model with the highest R² value of 0.56 and the lowest MSE of 174.07. Conclusion: The LightGBM model showed the best performance in predicting postoperative lung function.

• Journal of Chest Surgery
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• v.51 no.4
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• pp.280-282
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• 2018

Unilateral absence of a pulmonary artery (UAPA) is a rare congenital anomaly that may present with various symptoms, depending on the nature and severity of other cardiovascular anomalies. Furthermore, contralateral lung surgery in patients with UAPA is extremely rare, and clinical experience is limited. This report describes a case of surgical treatment of contralateral primary lung cancer in a patient with isolated UAPA. A 56-year-old man was diagnosed with primary lung cancer accompanied by isolated UAPA on the contralateral side. He underwent meticulous cardiorespiratory function tests preoperatively. We performed a right lower lobectomy. Although in the immediate postoperative period, the patient suffered from a mild decline in his respiratory function, he recovered uneventfully. The present case shows that preoperative awareness of UAPA and meticulous perioperative management enable contralateral lung surgery to be performed safely.

• Membrane Journal
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• v.14 no.1
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• pp.18-25
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• 2004

The purpose of this paper was to find out the proper equation to predict the gas transfer rate for designing intravenous artificial lung assist device. The prepared hollow fiber modules were examined under various experimental conditions through experimental modeling before inserted the artificial lung assist d $\varepsilon$ vice into as venous. As a result, we can estimate the gas transfer as a function of the packing density. The gas transfer obtained from the experiment was similar to that from the equation, confirming the usefulness equation. Therefore, we can conclude the gas transfer of the intravenous artificial lung assist device as a function of the packing density, and this functions are very useful for predicting the gas transfer of the intravenous artificial lung assist device.

• Molecules and Cells
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• v.43 no.9
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• pp.774-783
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• 2020

The lung has a vital function in gas exchange between the blood and the external atmosphere. It also has a critical role in the immune defense against external pathogens and environmental factors. While the lung is classified as a relatively quiescent organ with little homeostatic turnover, it shows robust regenerative capacity in response to injury, mediated by the resident stem/progenitor cells. During regeneration, regionally distinct epithelial cell populations with specific functions are generated from several different types of stem/progenitor cells localized within four histologically distinguished regions: trachea, bronchi, bronchioles, and alveoli. WNT signaling is one of the key signaling pathways involved in regulating many types of stem/progenitor cells in various organs. In addition to its developmental role in the embryonic and fetal lung, WNT signaling is critical for lung homeostasis and regeneration. In this minireview, we summarize and discuss recent advances in the understanding of the role of WNT signaling in lung regeneration with an emphasis on stem/progenitor cells.

• Korean Journal of Transplantation
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• v.28 no.3
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• pp.154-159
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• 2014

Background: Lung transplantation (LTx) is a life-saving treatment for patients with end-stage lung disease; however, the shortage of donor lungs has been a major limiting factor to increasing the number of LTx. Growing experience following LTx using donor lungs after cardiac death (DCD) has been promising, although concerns remain. The purpose of this study was to develop a DCD lung harvest model using an ex vivo lung perfusion (EVLP) system and to assess the function of presumably damaged lungs harvested from the DCD donor in pigs. Methods: The 40 kg pigs were randomly divided into the control group with no ischemic lung injury (n=5) and the study group (n=5), which had 1 hour of warm ischemic lung injury after cardiac arrest. Harvested lungs were placed in the EVLP circuit and oxygen capacities (OC), pulmonary vascular resistance (PVR), and peak airway pressure (PAP) were evaluated every hour for 4 hours. At the end of EVLP, specimens were excised for pathologic review and wet/dry ratio. Results: No statistically significant difference in OC (P=0.353), PVR (P=0.951), and PAP (P=0.651) was observed in both groups. Lung injury severity score (control group vs. study group: 0.700±0.303 vs. 0.870±0.130; P=0.230) and wet/dry ratio (control group vs. study group: 5.89±0.97 vs. 6.20±0.57; P=0.560) also showed no statistically significant difference between the groups. Conclusions: The function of DCD lungs assessed using EVLP showed no difference from that of control lungs without ischemic injury; therefore, utilization of DCD lungs can be a new option to decrease the number of deaths on the waiting list.

• Journal of Chest Surgery
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• v.22 no.5
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• pp.794-799
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• 1989

Sleeve lobectomy for bronchogenic carcinoma is an alternative to pneumonectomy. The extent and location of the tumor must be such that a sleeve procedure is feasible. The conservation of lung tissue benefits both compromised and uncompromised patients. From August 1988 to March 1989, five patients underwent sleeve lobectomy for bronchogenic carcinoma of the lung. The patients included four males and one female ranging in age from 52 years to 66 years. All patients were diagnosed as having squamous cell carcinoma. Operative procedures were right upper sleeve lobectomy in four cases and left upper sleeve lobectomy with pulmonary angioplasty in one case. Complications developed in one patient. An asthmatic attack necessitated ventilator support for one day. Bronchoscopic examinations were performed at two weeks and three months postoperatively in four patients. Anastomosis sites on all patients were intact, but in one case, nodules were noted. Pulmonary function tests were also checked at three months postoperatively, and showed good results. The reimplanted lobe or lobes contribute significantly to the overall remaining lung function. All patients are being followed up with satisfactory results, except one case of suspected local tumor recurrence. We think, therefore, that sleeve lobectomy is a safe and adequate procedure for patients with resectable lung cancer.

• Journal of the Korean Society of Physical Medicine
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• v.6 no.4
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• pp.437-445
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• 2011

Purpose : The purpose of this study was to analysis on diaphragm thickness and lung function of stroke patients by walking ability. Methods : We recruited thirty-five adults after stroke(20 male, 15 female) for our study. The subjects were divided into two groups; independent walking group(11 male, 9 female) and non-independent walking group(9 male, 6 female). Assessment of diaphragm thickness was performed using ultrasound in B-mode with a 7.5 MHz linea probe. During the experiment, the subject was seated in the chair. All subjects performed maximal expiratory flow maneuvers using a spirometer in order to determine the forced expiratory volume in 1 second ($FEV_1$), forced vital capacity(FVC), peak expiratory flow(PEF) and $FEV_1$/FVC. Chest expansion was measured with a tape-measure placed circumferentially around the chest wall at the xiphoid process. The collected data analyzed by independent t-test. Results : The diaphragm thickness were significant differences between the independent walking and nonindependent walking group. Values of forced vital capacity, forced expiratory volume at one second, peak expiratory flow in pulmonary function tests were significant differences between the independent walking and non-independent walking group. However, chest expansion were not significant differences in both of the group. Conclusion : This study showed that walking ability of stroke patients have influenced on diaphragm thickness and pulmonary function.

• Radiation Oncology Journal
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• v.31 no.1
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• pp.34-40
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• 2013

Purpose: To evaluate the predictive factors of radiation pneumonitis (RP) and associated changes in pulmonary function after definitive concurrent chemoradiotherapy (CCRT) in patients with non-small cell lung cancer (NSCLC). Materials and Methods: Medical records of 60 patients with NSCLC who received definitive CCRT were retrospectively reviewed. Dose volumetric (DV) parameters, clinical factors, and pulmonary function test (PFT) data were analyzed. RP was graded according to the CTCAE ver. 4.0. Percentage of lung volume that received a dose of threshold (Vdose) and mean lung dose (MLD) were analyzed for potential DV predictors. PFT changes were calculated as the difference between pre-RT and post-RT values at 3, 6, and 12 months after RT. Results: Twenty-two patients (37%) developed grade ${\geq}2$ RP. Among clinical factors, tumor location in lower lobe was associated with RP. Among the DV parameters, only MLD >15 Gy was associated with grade ${\geq}2$ RP. There were statistically significant decreases in PFT at all points compared with pre-RT values in grade ${\geq}2$ RP group. MLD was associated with forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) changes at 6 and 12 months. V10 was associated with FVC changes at 12 months. V20 and V30 were associated with FEV1 changes at 6 months and FVC changes at 12 months. Conclusion: After definitive CCRT in patients with NSCLC, MLD >15 Gy and lower lobe tumor location were predictors of grade ${\geq}2$ RP. Pulmonary functions were decreased after CCRT and the magnitude of changes was associated with DV parameters.