Publications by authors named "Chang-hoon Lee"

Background: Snoring is the cardinal symptom of obstructive sleep apnea (OSA). Snoring and upper airway obstruction associated with major oxygen desaturation may occur in populations undergoing flexible bronchoscopy.

Methods: To evaluate the prevalence of patients at a high risk of having OSA among patients undergoing bronchoscopy with sedation and to investigate whether snoring during the procedure predicts patients who are at risk of OSA, we prospectively enrolled 517 consecutive patients who underwent the procedure with moderate sedation.

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Background: Microbiological criteria for diagnosing nontuberculous mycobacterial pulmonary disease (NTM-PD) include positive culture results from at least two separately expectorated sputum specimens or one bronchial washing or lavage. However, the clinical similarities and differences between patients diagnosed by these two methods remain unclear. We compared clinical features and prognoses of patients with NTM-PD diagnosed from both specimen types.

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Ulmus macrocarpa Hance as an oriental medicinal plant has shown enormous potential for the treatment of several metabolic disorders in Korea. Hyperlipidemia, which is characterized by the excess accumulation of lipid contents in the bloodstream, may lead to several cardiovascular diseases. Therefore, in this study, anti-hyperlipidemic potential of U.

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Article Synopsis
  • Mucosal-associated invariant T (MAIT) cells, distinct from TCRα7.2 conventional T cells, are significant in inflammatory diseases like rheumatoid arthritis and inflammatory bowel disease.
  • This study utilized RNA sequencing to compare MAIT cells with TCRα7.2 conventional T cells and CD161 T cells, marking the first transcriptomic comparison of these cell types.
  • Through gene set enrichment and causal network analysis, researchers identified unique signaling pathways and genes associated with MAIT cell characteristics, enhancing our understanding of their biology.
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Previous studies have shown that transglutaminase 2 (TG2) induces epithelial to mesenchymal transition (EMT) in various tumors. Several studies have also demonstrated the critical role of microRNAs (miRNAs) in regulating EMT of various types of tumors. However, the relationship between TG2 and miRNAs is not well understood.

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Introduction: The association between GOLD categorizations and future exacerbations has not been fully investigated. This study elucidates whether the GOLD 2017 classification is associated with different future exacerbation risk in patients with chronic obstructive pulmonary disease (COPD) compared with the previous GOLD categorization. Another objective was to investigate the impacts of the symptoms and FEV1 on the predicted future exacerbation independently of previous exacerbation history.

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Background: Risk of exacerbations in chronic obstructive pulmonary disease (COPD) associated with biomass smoke has not been well addressed, although biomass smoke is similar in composition to tobacco smoke.

Methods: To investigate whether the risk of exacerbations in COPD associated with biomass smoke differs from that in COPD associated with tobacco smoke, we recruited patients with COPD from two Korean multicenter prospective cohorts. In a multiple linear regression model, the standardized regression coefficient (β) of biomass smoke exposure ≥25 years was most similar to that (β) of tobacco smoke exposure ≥10 pack-years (β = - 0.

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Purpose: The economic effect of regular follow-up and early management in patients with early chronic obstructive pulmonary disease (COPD) has not yet been clarified. Therefore, this study aimed to estimate the economic effect of regular follow-up and early management in these patients.

Methods: Patients with early COPD were identified from the Korea National Health and Nutrition Examination Survey.

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The aim of this study is to clarify whether the combined evaluation of resting hyperinflation and emphysema confers any additional advantages in terms of predicting clinical outcomes in chronic obstructive pulmonary disease (COPD) patients. We included COPD patients from the Korean Obstructive Lung Disease (KOLD) cohort. Patients with a residual volume/total lung capacity (RV/TLC) over the upper limit of normal were defined as having resting hyperinflation, and those with an emphysema index >10% were defined as having emphysema.

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Background: Respiratory failure requiring intubation is a risk factor for mortality in immunocompromised patients, therefore, noninvasive methods to avoid intubation are preferred in such patients. A high-flow nasal cannula (HFNC) is an alternative noninvasive technique for oxygen delivery but can be potentially harmful in cases of delayed intubation. We sought to identify the physiological predictors of outcome to assess the responsiveness to HFNC of immunocompromised patients with acute respiratory failure.

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Breast cancer remains the second leading cause of cancer death among woman, worldwide, despite advances in identifying novel targeted therapies and the development of treating strategies. Classification of clinical subtypes (ER+, PR+, HER2+, and TNBC (Triple-negative)) increases the complexity of breast cancers, which thus necessitates further investigation. Mouse models used in breast cancer research provide an essential approach to examine the mechanisms and genetic pathway in cancer progression and metastasis and to develop and evaluate clinical therapeutics.

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Objective: Curdlan has been widely used as a gelling agent in various food systems. This study was performed to evaluate the rheological properties of pork myofibrillar protein (MP) with different levels of curdlan (0.5% to 1.

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Human epidermal growth factor receptor 2 (HER2) inhibitors, such as trastuzumab and lapatinib are used to treat HER2-positive breast and gastric cancers. However, as with other targeted therapies, intrinsic or acquired resistance to HER2 inhibitors presents unresolved therapeutic problems for HER2-positive gastric cancer. The present study describes investigations with AUY922, a heat shock protein 90 (HSP90) inhibitor, in primary lapatinib-resistant (ESO26 and OE33) and lapatinib-sensitive gastric cancer cells (OE19, N87, and SNU-216) harboring HER2 amplification/over-expression.

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Purpose: While GOLD classification has been revised, its clinical impacts on outcomes of COPD patients have not been widely evaluated in real-world cohorts.

Materials And Methods: According to 2007, 2013, and 2017 GOLD classifications, distribution and clinical characteristics of group-shifted patients and the risk of acute exacerbation were analyzed in combined Korean COPD cohorts. Future risk for annual moderate-to-severe exacerbation was estimated as incidence rate ratio (IRR) and compared by groups.

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Background: Linezolid improves the treatment outcomes of multidrug-resistant tuberculosis substantially. We investigated whether use of linezolid instead of ethambutol increases the proportion of sputum culture conversion at 8 weeks of treatment in patients with pulmonary tuberculosis.

Methods: We did a phase 2, multicentre, randomised, open-label trial for patients with pulmonary tuberculosis at the three affiliated hospitals to Seoul National University and National Medical Center (Seoul-Seongnam, South Korea).

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Background And Objectives: Aortic valve replacement (AVR) is the treatment of choice in severe symptomatic aortic stenosis (AS) patients. However, a substantial number of elderly patients refuse AVR and treated medically. We investigated their long-term prognosis.

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IκB, a cytoplasmic inhibitor of nuclear factor-κB (NF-κB), is reportedly degraded via the proteasome. However, we recently found that long-term incubation with proteasome inhibitors (PIs) such as PS-341 or MG132 induces IκBα degradation via an alternative pathway, lysosome, which results in NF-κB activation and confers resistance to PI-induced lung cancer cell death. To enhance the anti-cancer efficacy of PIs, elucidation of the regulatory mechanism of PI-induced IκBα degradation is necessary.

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Epithelial mesenchymal transition (EMT) is a biological process that plays a critical role in cancer progression. Blocking the process of EMT can be an essential strategy in the development of anticancer drugs. In this paper, we briefly introduce recent research trends and issues of EMT, focusing on the relationship of EMT with the entire cycle of inflammation (from initiation to resolution of inflammation).

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The pitting corrosion resistance and passive behavior of type 304 borated stainless steels (Fe⁻18Cr⁻12Ni⁻1.5Mn⁻(0.19, 0.

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It is well known that diabetic patients have a high risk of cardiovascular events, and although there has been a tremendous effort to reduce these cardiovascular risks, the incidence of cardiovascular morbidity and mortality in diabetic patients remains high. Therefore, the early detection of coronary artery disease (CAD) is necessary in those diabetic patients who are at risk of cardiovascular events. Significant medical and radiological advancements, including coronary computed tomography angiography (CCTA), mean that it is now possible to investigate the characteristics of plaques, instead of solely evaluating the calcium level of the coronary artery.

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Background: The association between the location of non-small cell lung cancer (NSCLC) and prognosis is a debated issue. Some studies have provided evidence of better prognosis of upper lobe tumors than lower to middle lobe tumors, while other studies have reported contrasting conclusions. The aim of this study was to further assess this association through a systematic review and meta-analysis.

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Herein, we report the unique case of a 75-year-old male patient who had undergone a left upper lobectomy for lung cancer and developed an incidental superficial endobronchial squamous cell carcinoma in the right upper lobe that was not localizable on modern cross-sectional imaging modalities. The superficial endobronchial squamous cell carcinoma was successfully localized by computed tomography-driven virtual reality endoscopy and was identically matched with a small, whitish, patch lesion on bronchoscopy. The localized lesion was annotated on the corresponding computed tomography images, and illustrated in a fabricated three-dimensional (3D)-printed airway model.

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Disruption of the healthy intestinal microbiome and homeostasis of the intestinal immune system, which are closely interactive, are two key factors for ulcerative colitis. Here, we show that MI-2, a selective inhibitor of mucosa-associated lymphoid tissue lymphoma translocation-1 (MALT1), alleviated excessive inflammatory responses and was associated with restoration of healthy intestinal microbiome in mice suffering from dextran sulfate sodium (DSS)-induced colitis. We found that the diversity of intestinal microbiome of mice with DSS-induced colitis was significantly lower than that of healthy mice.

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Cytosolic protein tyrosine phosphatase epsilon (cyt-PTPε) plays a central role in controlling differentiation and function of osteoclasts, whose overactivation causes osteoporosis. Based on our previous study reporting a number of cyt-PTPε inhibitory chemical compounds, we carried out a further and extended analysis of our compounds to examine their effects on cyt-PTPε-mediated dephosphorylation and on osteoclast organization and differentiation. Among five compounds showing target selectivity to cyt-PTPε over three other phosphatases in vitro, two compounds exhibited an inhibitory effect against the dephosphorylation of cellular Src protein, the cyt-PTPε substrate.

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