Highest fusion performance without harmful edge energy bursts in tokamak

The path of tokamak fusion and International thermonuclear experimental reactor (ITER) is maintaining high-performance plasma to produce sufficient fusion power. This effort is hindered by the transient energy burst arising from the instabilities at the boundary of plasmas. Conventional 3D magnetic perturbations used to suppress these instabilities often degrade fusion performance and increase the risk of other instabilities. This study presents an innovative 3D field optimization approach that leverages machine learning and real-time adaptability to overcome these challenges. Implemented in the DIII-D and KSTAR tokamaks, this method has consistently achieved reactor-relevant core confinement and the highest fusion performance without triggering damaging bursts. This is enabled by advances in the physics understanding of self-organized transport in the plasma edge and machine learning techniques to optimize the 3D field spectrum. The success of automated, real-time adaptive control of such complex systems paves the way for maximizing fusion efficiency in ITER and beyond while minimizing damage to device components.

Endobronchial valves for emphysema and persistent air-leak: 10-year experience in an Asian country

BACKGROUND

Endobronchial valve (EBV) therapy, a validated method for bronchoscopic lung volume reduction (BLVR) in severe emphysema, has been explored for persistent air-leak (PAL) management. However, its effectiveness and safety in the Asian population require further real-world evaluation. In this study, we assessed the outcomes of treatment with EBV within this demographic.

METHODS

We conducted a retrospective analysis of medical records from 11 Korean centers. For the emphysema cohort, inclusion criteria were patients diagnosed with emphysema who underwent bronchoscopy intended for BLVR. We assessed these patients for clinical outcomes of chronic obstructive pulmonary disease. All patients with PAL who underwent treatment with EBV were included. We identified the underlying causes of PAL and evaluated clinical outcomes after the procedure.

RESULTS

The severe emphysema cohort comprised 192 patients with an average age of 70.3 years, and 95.8% of them were men. Ultimately, 137 underwent treatment with EBV. Three months after the procedure, the BLVR group demonstrated a significant improvement in forced expiratory volume in 1 s (+160 mL vs. +30 mL; P = 0.009). Radiographic evidence of lung volume reduction 6 months after BLVR was significantly associated with improved survival (adjusted hazard ratio 0.020; 95% confidence interval 0.038-0.650; P = 0.010). Although pneumothorax was more common in the BLVR group (18.9% vs. 3.8%; P = 0.018), death was higher in the no-BLVR group (38.5% vs. 54.5%, P = 0.001), whereas other adverse events were comparable between the groups. Within the subset of 18 patients with PAL, the predominant causes of air-leak included spontaneous secondary pneumothorax (44.0%), parapneumonic effusion/empyema (22.2%), and post-lung resection surgery (16.7%). Following the treatment, the majority (77.8%) successfully had their chest tubes removed. Post-procedural complications were minimal, with two incidences of hemoptysis and one of empyema, all of which were effectively managed.

CONCLUSIONS

Treatment with EBV provides substantial clinical benefits in the management of emphysema and PAL in the Asian population, suggesting a favorable outcome for this therapeutic approach.

Search for Boosted Dark Matter in COSINE-100

We search for energetic electron recoil signals induced by boosted dark matter (BDM) from the galactic center using the COSINE-100 array of NaI(Tl) crystal detectors at the Yangyang Underground Laboratory. The signal would be an excess of events with energies above 4 MeV over the well-understood background. Because no excess of events are observed in a 97.7  kg·yr exposure, we set limits on BDM interactions under a variety of hypotheses. Notably, we explored the dark photon parameter space, leading to competitive limits compared to direct dark photon search experiments, particularly for dark photon masses below 4 MeV and considering the invisible decay mode. Furthermore, by comparing our results with a previous BDM search conducted by the Super-Kamionkande experiment, we found that the COSINE-100 detector has advantages in searching for low-mass dark matter. This analysis demonstrates the potential of the COSINE-100 detector to search for MeV electron recoil signals produced by the dark sector particle interactions.

Identification of predictive factors for early relapse in patients with unresectable stage III non-small cell lung cancer receiving consolidation durvalumab after concurrent chemoradiation therapy

BACKGROUND

Patients with locally advanced, unresectable, non-small cell lung cancer (NSCLC) receiving definitive concurrent chemoradiation therapy (CCRT) benefit from durvalumab consolidation therapy. However, predictive factors for early relapse during durvalumab maintenance have not yet been identified.

METHODS

The present study included the lung cancer cohort of the Catholic Medical Centers at the Catholic University of Korea from January 2018 to December 2021. A total of 51 NSCLC patients treated with durvalumab consolidation therapy after definitive CCRT were included in the analysis. Early relapse was defined as patients experiencing relapse within 6 months of starting initial durvalumab therapy.

RESULTS

Among the 51 patients, 15 (29.4%) relapsed during the study period. Median time from initial therapy of durvalumab to progression was 451.00 ± 220.87 days (95% confidence interval [CI]: 18.10-883.90) in overall patients. In multivariate analysis, younger age (adjusted odds ratio [aOR], 0.792; 95% CI: 0.642-0.977; p = 0.030), higher pack-years (aOR, 1.315; 95% CI: 1.058-1.635; p = 0.014), non-COPD (aOR, 0.004; 95% CI: 0.000-0.828; p = 0.004) and anemia (aOR, 234.30; 95% CI: 1.212-45280.24; p = 0.042), were independent predictive factors for early relapse during durvalumab consolidation therapy.

CONCLUSION

Younger age, higher number of pack-years, non-COPD, and anemia were independent predictive factors for early relapse during durvalumab consolidation therapy in patients with unresectable stage III NSCLC after definitive CCRT. Careful patient selection and clinical attention are needed for high-risk individuals.

Smoking Status at Time of Diagnosis Affects the Efficacy of Anti-PD-1/L1 Therapy in Patients With Advanced NSCLC

BACKGROUND/AIM

Programmed death ligand-1 (PD-L1) expression is known to be a predictive biomarker for response to immunotherapy in non-small cell lung cancer (NSCLC). However, PD-L1 is not always a reliable predictive biomarker. In the present study, we aimed to compare responses to immunotherapy according to smoking status in NSCLC patients receiving immunotherapy in second line or further line treatment.

PATIENTS AND METHODS

The lung cancer registry database of the Catholic Medical Center, Seoul, Republic of Korea was used. Patients were eligible for this study if they were diagnosed with histologically confirmed NSCLC and received immune checkpoint inhibitors (ICIs) as second-line or further line therapy from January 2017 to December 2021.

RESULTS

Overall, 220 patients with NSCLC treated with ICIs were enrolled. There were 40 never smokers, 73 former smokers, and 107 current smokers. In multivariate analysis, smoking status, pathologic type, and PD-L1 expression were significant factors affecting PFS. Sex, ECOG performance status, pathologic type, and PD-L1 expression were significant factors affecting OS.

CONCLUSION

Smoking status at diagnosis of lung cancer could be a predictive biomarker for response to ICIs in patients with advanced NSCLC.

Metabolic Disorders Are Associated With Drug-Induced Liver Injury During Antituberculosis Treatment: A Multicenter Prospective Observational Cohort Study in Korea

Background

Drug-induced liver injury (DILI) may lead to the discontinuation of antituberculosis (anti-TB) treatment (ATT). Some studies have suggested that metabolic disorders increase the risk of DILI during ATT. This study aimed to identify risk factors for DILI, particularly metabolic disorders, during ATT.

Methods

A multicenter prospective observational cohort study to evaluate adverse events during ATT was conducted in Korea from 2019 to 2021. Drug-susceptible patients with TB who had been treated with standard ATT for 6 months were included. The patients were divided into 2 groups depending on the presence of 1 or more metabolic conditions, such as insulin resistance, hypertension, obesity, and dyslipidemia. We monitored ATT-related adverse events, including DILI, and treatment outcomes. The incidence of DILI was compared between individuals with and without metabolic disorders, and related factors were evaluated.

Results

Of 684 patients, 52 (7.6%) experienced DILI, and 92.9% of them had metabolic disorders. In the multivariable analyses, underlying metabolic disorders (adjusted hazard ratio [aHR], 2.85; 95% CI, 1.01-8.07) and serum albumin <3.5 g/dL (aHR, 2.26; 95% CI, 1.29-3.96) were risk factors for DILI during ATT. In the 1-month landmark analyses, metabolic disorders were linked to an elevated risk of DILI, especially significant alanine aminotransferase elevation. The treatment outcome was not affected by the presence of metabolic disorders.

Conclusions

Patients with metabolic disorders have an increased risk of ATT-induced liver injury compared with controls. The presence of metabolic disorders and hypoalbuminemia adversely affects the liver in patients with ATT.

Prediction of postoperative lung function in lung cancer patients using machine learning models

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 (CDW) and developed 3 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 one second (FEV1) 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 3 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.

Association between quality of life questionnaire at diagnosis and survival in patients with lung cancer

BACKGROUND

Patients with lung cancer experience considerable symptom burden, which can decrease patients' QOL. Our aim was to investigate the association between QOL questionnaire at diagnosis and survival of lung cancer.

PATIENTS AND METHODS

This was a multicenter study of lung cancer patients at 7 medical centers of the Catholic University of Korea that responded to a quality of life questionnaire between December 1, 2017 and December 31, 2020. We analyzed 5 functional (physical, role, emotional, cognitive, and social functioning) and nine symptom (fatigue, nausea and vomiting, pain, dyspnea, insomnia, appetite loss, constipation, diarrhea, and financial difficulties) scales and examined their associations with survival. A Cox proportional hazards model was used to evaluate the prognostic value.

RESULTS

In total, 1297 lung cancer patients were enrolled. The results of multivariable analysis showed that female, younger age, never smoker, stage I or II cancer, higher physical functioning, and emotional functioning were statistically significant favorable predictors for survival. On subgroup analysis according to early (stage I and II) or advanced (stage III or IV) stage, higher physical functioning and emotional functioning were each found to be favorable prognostic factors for survival. Meanwhile, fatigue, pain, insomnia, and financial difficulties were found to be associated with low scores on the emotional functioning scale; fatigue, pain, dyspnea, and financial difficulties were associated with low scores on the physical functioning scale.

CONCLUSION

Assessing the physical functioning and emotional functioning scales of QOL questionnaire items at diagnosis can help clinicians predict the survival of patients with lung cancer.

Differences in clinical significance of bronchodilator responses measured by forced expiratory volume in 1 second and forced vital capacity

BACKGROUND

The clinical implication of bronchodilator response (BDR) is not fully understood. However, BDR is frequently present in patients with chronic obstructive pulmonary disease (COPD). We identified the differences in clinical features regarding BDR. In addition, we divided BDR into BDR for forced expiratory volume in 1 s (FEV1) and BDR for forced vital capacity (FVC; i.e., BDR-FEV1 and BDR-FVC, respectively) and analyzed clinical significance.

METHODS

We used data from the Korea COPD Subgroup Study, a multicenter cohort study of COPD patients recruited from 54 centers in South Korea since April 2012. We analyzed differences in baseline characteristics, 1-year exacerbation rate, and 3-year FEV1 decline between BDR negative and positive patients. Moreover, we analyzed the differences in clinical features between BDR-FEV1 positive and negative patients and between BDR-FVC positive and negative patients.

RESULTS

Of the 2,181 patients enrolled in this study, 366 (16.8%) were BDR positive. BDR positive patients were more likely to be ever-smokers and to have a lower body mass index and higher symptom scores compared to BDR negative patients. Baseline FEV1 and FEV1/FVC were lower in the BDR positive compared to the BDR negative group (1.7 ± 0.6 and 1.6 ± 0.5, respectively, p < 0.01; 50.9 ± 12.1 and 46.5 ± 14.8, respectively, p < 0.01). BDR positive patients were more likely to have been diagnosed with asthma-COPD overlap and to receive inhaled corticosteroids (ICS) than BDR negative patients. BDR-FVC patients were more likely to be smokers, suffer from worse symptoms and have lower lung function than those with no BDR-FVC. BDR had no significant effect on 1-year moderate to severe or severe exacerbation rates or 3-year annual FEV1 decline. Interactive effects of ICS and BDR on the exacerbation rate were not significant in any group.

CONCLUSIONS

In this study, BDR positive patients were more likely to be ever-smokers and to have worse symptoms and lung function than BDR negative patients. BDR-FVC was associated with worse symptom control and lung function compared to BDR-FEV1. However, there were no significant differences in exacerbation rate or decline in lung function in any BDR group. In addition, the effects of ICS on exacerbations were not significant in any group.

The association between clinical parameters and resectability in stage III non-small cell lung cancer, and a combination of N2 lymph node burden and lung immune prognostic index score as a potential biomarker

Background

Surgery is important treatment option for stage III non-small cell lung cancer (NSCLC) because of its curative potential. We investigated the characteristics of resectable patients, and compared the outcomes according to treatment modalities.

Methods

Among 1,092 patients with NSCLC diagnosed between 2008 to 2020 from 7 university hospitals of Catholic Medical Center, we retrospectively analyzed 252 patients with clinical or pathological stage III. We compared survival outcomes among the groups according to resectability, first-line treatments, and the lung immune prognostic index (LIPI) score. Clinical N2 subgroup was analyzed using multi-parameter scoring system.

Results

The resectable group consisted of less smokers, showed better pulmonary function and lower inflammatory markers, and tended to be diagnosed as earlier cancer stage than the unresectable group. The resectable group showed better progression-free survival (PFS) and overall survival (OS) than the unresectable group (P<0.001 and P<0.001, respectively). Regarding the first-line treatment, surgery showed the longest median PFS (33.70 months) and the highest 12-month OS rate (91.6%) than the other treatment modalities. OS was significantly different depending on the LIPI score in whole population, as well as in the unresectable group (P=0.004 and P=0.003, respectively). LIPI 0 group exhibited better OS than LIPI 1 and 2 in both populations. Eastern Cooperative Oncology Group (ECOG) 2-4, LIPI 1-2, and first-line treatment were independent prognostic factors for OS. Smoking, forced expiratory volume in the first second (FEV1) and more advanced cancer stage were associated with unresectability. In subgroup analysis of N2 disease, we attempted to create new scoring system combining lymph node (LN) status and LIPI score. This scoring system showed significant association with OS.

Conclusions

The patients with resectable stage III NSCLC showed better PFS and OS than the patients with unresectable tumor. LIPI score exhibited possibility to be used as potential biomarker in stage III NSCLC. The multi-parameter scoring system using LN status and LIPI score was predictive of OS in the N2 subgroup.

Investigation of poor predictive factors in extensive stage small cell lung cancer under etoposide-platinum-atezolizumab treatment

BACKGROUND

The phase III trial IMpower133 showed that platinum and etoposide plus atezolizumab was associated with improved overall survival (OS) and progression free-survival (PFS) when compared to the placebo group in treatment-naïve extensive stage (ES) small cell lung cancer (SCLC). Due to superiority in clinical outcomes, combination immunotherapy plus chemotherapy have become mainstay treatment modalities as first-line treatment in ES-SCLC. Nevertheless, real-world data are still lacking and the search for potential biomarkers is essential. This study aimed to evaluate potential predictive biomarkers applicable in ES-SCLC under combination therapy.

METHODS

Patients with ES-SCLC under etoposide-platinum-atezolizumab enrolled from seven university hospitals affiliated to the Catholic University of Korea were evaluated. Pretreatment clinical parameters were evaluated for association with OS and PFS. Adverse events (AEs) during induction and maintenance phases were also evaluated. p-values below 0.05 were considered statistically significant.

RESULTS

A total of 41 patients were evaluated. Six-month survival was 68.6%. As best response to treatment, 26 (63.4%) showed partial response, nine (22.0%) showed stable disease, and four (9.8%) showed progressive disease. During the induction phase, grade I-II AEs occurred in 22 (53.7%) patients, and grade III-IV AEs occurred in 26 (63.4%) patients. During the maintenance phase, nine out of 25 (36.0%) patients experienced any grade AEs. In multivariate analysis for OS, lactate dehydrogenase (LDH), c-reactive protein (CRP), and forced vital capacity (%) were significant factors. In multivariate analysis for PFS, sex, and LDH were significant.

CONCLUSION

In ES-SCLC under etoposide-platinum-atezolizumab, pretreatment CRP, LDH and FVC (%) were independent predictive factors.

Early adolescents’ sexual and reproductive health literacy in Lao PDR

Background

Sexual and reproductive health literacy (SRHL) refers to the ability to access, understand, appraise, and apply information for decision-making related to sexual and reproductive health. The low level of SRHL in adolescents increases their sexually risky behaviors and endangers sexual health. Although early adolescence is a critical development period for forming initial views on sexuality and is often a time for attempting risky behaviors, studies on SRHL for early adolescents are fairly limited in Las PDR. As an initial step for the development of a global health project between Lao PDR and South Korea, this study assessed the level of SRHL and the differences in gender among early adolescents in Lao PDR.

Methods

Participants were 235 students conveniently recruited from one junior high school each in two provinces in Lao PDR. SRHL was measured using the 39-item Teen Pregnancy Health Literacy scale consisting of 4 subscales of finding, understanding, appraisal, and application. The scores were classified into inadequate, problematic, sufficient, and excellent using the SRHL index formula. The mean differences in gender were compared using t-test.

Results

The mean of the SRHL scores of the participants was 19.07 (±10.57). The mean score was significantly lower for girls, at 17.67 (±11.22) than for boys, at 21.37 (±9.05) (p = .006). Significant differences were further identified in all four sub-domains of SRHL: finding (p = .025), understanding (p = .005), appraisal (p = .041), and application (p = .029). The majority of participants (91.7%) were categorized as having an ‘inadequate’ or ‘problematic’ level of SRHL.

Conclusions

The level of SRHL among most early adolescents was found to be inadequate. The level of SRHL among girls was much lower than that among boys. The findings suggest a gender-specific approach to developing health education programs to improve SRHL among early adolescents and prevent future sexually risky behaviors in Lao PDR.

Key messages

Characterization of rhodanine derivatives as potential disease-modifying drugs for experimental mouse osteoarthritis

OBJECTIVE

This study was performed to characterize selected rhodanine derivatives as potential preclinical disease-modifying drugs for experimental osteoarthritis (OA) in mice.

METHODS

Three rhodanine derivatives, designated rhodanine (R)-501, R-502, and R-503, were selected as candidate OA disease-modifying drugs. Their effects were evaluated by intra-articular (IA) injection in OA mouse models induced by DMM (destabilization of the medial meniscus) or adenoviral overexpression in joint tissues of hypoxia-inducible factor (HIF)-2α or zinc importer ZIP8. The regulatory mechanisms impacted by the rhodanine derivatives were examined in primary-culture chondrocytes and fibroblast-like synoviocytes (FLS).

RESULTS

All three rhodanine derivatives inhibited OA development caused by DMM or overexpression of HIF-2α or ZIP8. Compared to vehicle-treated group, for example, IA injection of R-501 in DMM-operated mice reduced median OARSI grade from 3.78 (IQR 3.00-5.00) to 1.89 (IQR 0.94-2.00, P = 0.0001). R-502 and R-503 also reduced from 3.67 (IQR 2.11-4.56) to 2.00 (IQR 1.00-2.00, P = 0.0030) and 2.00 (IQR 1.83-2.67, P = 0.0378), respectively. Mechanistically, the rhodanine derivatives inhibited the nuclear localization and transcriptional activity of HIF-2α in chondrocytes and FLS. They did not bind to Zn²⁺ or modulate Zn²⁺ homeostasis in chondrocytes or FLS; instead, they inhibited the nuclear localization and transcriptional activity of the Zn²⁺-dependent transcription factor, MTF1. HIF-2α, ZIP8, and interleukin-1β could upregulate matrix-degrading enzymes in chondrocytes and FLS, and the rhodanine derivatives inhibited these effects.

CONCLUSION

IA administration of rhodanine derivatives significantly reduced OA pathogenesis in various mouse models, demonstrating that these derivatives have disease-modifying therapeutic potential against OA pathogenesis.

Comparison of different regimens with or without fluoroquinolone in isoniazid-resistant tuberculosis: A multicenter cohort study

In 2018, the World Health Organization recommended a 6-month four-drug regimen (rifampicin, ethambutol, pyrazinamide, and levofloxacin) for the treatment of isoniazid-monoresistant tuberculosis. However, the regimen had very low certainty. This cohort study assessed the impact of fluoroquinolone use and initial baseline regimen on treatment effectiveness in isoniazid-monoresistant tuberculosis. This multicenter retrospective cohort study included 318 patients with isoniazid-monoresistant tuberculosis notified between 2011 and 2018 in Korea. Baseline regimens were classified into two groups, namely 6–9-month rifampicin, ethambutol, and pyrazinamide (6-9REZ) and a combination regimen of 2-month rifampicin, ethambutol, pyrazinamide and 7–10-month rifampicin and ethambutol (2REZ/7-10RE). Multivariable logistic regression was performed to assess factors associated with positive treatment outcomes. Of 318 enrolled patients, 234 (73.6%) were treated with the 6-9REZ and 103 (32.4%) with additional fluoroquinolone. In a multivariable logistic regression model comparing the 6-9REZ and 2REZ/7-10RE groups, there was no difference in the odds of positive outcomes (adjusted odds ratio = 1.08, 95% confidence interval = 0.65–1.82). Addition use of fluoroquinolone was not associated with positive treatment outcomes in the whole cohort (adjusted odds ratio = 1.41, 95% confidence interval = 0.87–2.27); however, its additional use was beneficial in the 2REZ/7-10RE subgroup (adjusted odds ratio = 3.58, 95% confidence interval = 1.32–9.75). Both initial baseline regimens, 6-9REZ and 2REZ/7-10RE, were similarly effective. Shortening of the pyrazinamide administration duration with additional fluoroquinolone use could be a safe alternative for patients with potential hepatotoxicity related to pyrazinamide.

Association of weight change following smoking cessation with the risk of tuberculosis development: A nationwide population-based cohort study

Background

Smoking or weight loss is a risk of tuberculosis (TB) development. However, the impact of weight change after smoking cessation on the occurrence of TB remains elusive. We aimed to determine the relationship between weight change after smoking cessation and the risk of TB development.

Methods

We conducted a population-based cohort study using the national database in Republic of Korea. Of the 10,490,491 subjects who underwent health check-up in 2009, we enrolled 9,953,124 subjects without a previous TB history and followed them until 2017. We divided all study participants into the following three groups: never, former, and current smokers. The primary endpoint was newly developed TB.

Results

Among 9,953,124 subjects analyzed, 5,922,845 (59.5%) were never smokers, 1,428,209 (14.4%) were former smokers, and 2,602,080 (26.1%) were current smokers. The risk of TB development was significantly higher in current smokers than in never smokers (adjusted hazard ratio (aHR) 1.158; 95% confidence interval [CI] 1.131–1.186). Among current smokers, individuals who stopped smoking and maintained weight after baseline evaluation had a significantly lower risk of TB development compared with those who continued to smoke (aHR 0.771; 95% CI 0.741–0.892). However, even after smoking cessation, individuals who lost weight were at a significantly higher risk of TB development compared with those who continued to smoke (aHR 1.327; 95% CI 1.119–1.715).

Conclusions

Our findings suggest that smoking is a risk factor for TB and weight maintenance (neither gaining or losing) after quitting smoking might reduce the risk of TB development.

Association between lung function and the risk of atrial fibrillation in a nationwide population cohort study

We investigated the association between lung function and atrial fibrillation (AF) in 21,349 adults without AF aged ≥ 40 years who underwent spirometry. The study participants were enrolled from the Korean National Health and Nutritional Examination Survey between 2008 and 2016. The primary outcome was new-onset non-valvular AF identified from the National Health Insurance Service database. During the median follow-up of 6.5 years, 2.15% of participants developed new-onset AF. The incidence rate of AF per 1000 person-years was inversely related to the forced expiratory volume in 1 s (FEV₁), forced vital capacity (FVC), and FEV₁/FVC quartile. After adjustment for multiple variables, the AF risk in the lowest FEV₁ quartile was 1.64-fold higher than that in the highest quartile (hazard ratio (HR) 1.64 (95% confidence interval (CI) 1.26–2.12) for lowest FEV₁ quartile). The lowest quartile of FVC had 1.56-fold higher AF risk than the highest quartile (HR 1.56 (95% CI 1.18–2.08) for lowest FVC quartile). Although the lowest FEV₁/FVC quartile was associated with an increased risk of AF in the unadjusted model, this increased risk was not statistically significant in the multivariable analysis. Compared to those with normal lung function, participants with restrictive or obstructive lung function had 1.49 and 1.42-fold higher AF risks, respectively. In this large nationwide cohort study, both obstructive and restrictive patterns of reduced lung function were significantly associated with increased AF risk.

Integrative analysis of lung molecular signatures reveals key drivers of idiopathic pulmonary fibrosis

Background

Idiopathic pulmonary fibrosis (IPF) is a devastating disease with a high clinical burden. The molecular signatures of IPF were analyzed to distinguish molecular subgroups and identify key driver genes and therapeutic targets.

Methods

Thirteen datasets of lung tissue transcriptomics including 585 IPF patients and 362 normal controls were obtained from the databases and subjected to filtration of differentially expressed genes (DEGs). A functional enrichment analysis, agglomerative hierarchical clustering, network-based key driver analysis, and diffusion scoring were performed, and the association of enriched pathways and clinical parameters was evaluated.

Results

A total of 2,967 upregulated DEGs was filtered during the comparison of gene expression profiles of lung tissues between IPF patients and healthy controls. The core molecular network of IPF featured p53 signaling pathway and cellular senescence. IPF patients were classified into two molecular subgroups (C1, C2) via unsupervised clustering. C1 was more enriched in the p53 signaling pathway and ciliated cells and presented a worse prognostic score, while C2 was more enriched for cellular senescence, profibrosing pathways, and alveolar epithelial cells. The p53 signaling pathway was closely correlated with a decline in forced vital capacity and carbon monoxide diffusion capacity and with the activation of cellular senescence. CDK1/2, CKDNA1A, CSNK1A1, HDAC1/2, FN1, VCAM1, and ITGA4 were the key regulators as evidence by high diffusion scores in the disease module. Currently available and investigational drugs showed differential diffusion scores in terms of their target molecules.

Conclusions

An integrative molecular analysis of IPF lungs identified two molecular subgroups with distinct pathobiological characteristics and clinical prognostic scores. Inhibition against CDKs or HDACs showed great promise for controlling lung fibrosis. This approach provided molecular insights to support the prediction of clinical outcomes and the selection of therapeutic targets in IPF patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01749-3.

Biocompatible N-acetyl-nanoconstruct alleviates lipopolysaccharide-induced acute lung injury in vivo

Oxidative stress plays important roles in inflammatory responses during acute lung injury (ALI). Recently, nanoconstruct (Nano)-based drug-delivery systems have shown promise in many models of inflammation. In this study, we evaluated the anti-inflammatory effects of N-acetylcysteine (NAC) loaded in a biocompatible Nano using a rat model of ALI. We synthesized a Nano with a good NAC-releasing capacity using porous silica Nano, which was used to produce Nano/NAC complexes. For in vivo experiments, Sprague–Dawley rats were intraperitoneally administered NAC or Nano/NAC 30 min after intratracheal instillation of lipopolysaccharide. After 6 h, bronchoalveolar lavage fluids and lung tissues were collected. The anti-oxidative effect of the Nano/NAC complex was confirmed by demonstrating reduced levels of reactive oxygen species after treatment with the Nano/NAC in vitro. In vivo experiments also showed that the Nano/NAC treatment may protect against LPS‐induced ALI thorough anti‐oxidative and anti‐inflammatory effects, which may be attributed to the inactivation of the NF‐κB and MAPK pathways. In addition, the effects of Nano/NAC treatment were shown to be superior to those of NAC alone. We suggest the therapeutic potential of Nano/NAC treatment as an anti‐inflammatory agent against ALI. Furthermore, our study can provide basic data for developing nanotechnology-based pharmacotherapeutics for ALI.

Significance of Glasgow Prognostic Scores in NSCLC Patients Treated With Immunotherapy After Platinum-based Cytotoxic Chemotherapy

BACKGROUND/AIM

Little is known about the prognostic role of the Glasgow prognostic score (GPS) in non-small cell lung cancer (NSCLC) patients treated with immunotherapy after platinum-based cytotoxic chemotherapy.

PATIENTS AND METHODS

This study used a lung cancer cohort of the Catholic Medical Center of Korea between January 2018 and September 2020.

RESULTS

A total of 78 patients with NSCLC treated with immunotherapy as second or further-line therapy were included. Higher GPS values were significant predictors of shorter immune-related progression-free survival (irPFS) and overall survival (OS). The hazard ratios for irPFS were 0.249 for programmed death-ligand 1 (PD-L1) expression ≥50% and 9.73 for a GPS of 2. Older age, lower PD-L1 expression and higher GPS values were independently associated with shorter OS.

CONCLUSION

Higher GPS values were identified as a poor prognostic factor for OS and irPFS in NSCLC patients who received immunotherapy as second or further-line therapy.

Increased risk of chronic otitis media in chronic rhinosinusitis patients: a longitudinal follow-up study using a national health screening cohort

BACKGROUND

Chronic rhinosinusitis (CRS) and chronic otitis media (COM) share pathophysiological mechanisms such as bacterial infection, biofilm, and persistence of the obstruction state of ventilation routes. However, only a few studies have investigated the relationship between these two diseases nationwide and in the general population. The purpose of this study was to determine whether the incidence of COM in patients with CRS differed from that of a matched control from the national health screening cohort.

METHODS

Data from the Korean Health Insurance Review and Assessment Service-National Patient Samples were collected from 2002 to 2015. Participants who were treated ≥ ≥ ≥2 times and underwent head and neck computed tomography evaluation were selected. A 1:4 matched CRS group (n=8,057) and a control group (n=32,228) were selected. The control group included participants who were never treated with the ICD-10 code J32 from 2002 to 2015. The CRS group included CRS patients with/without nasal polyps.

RESULTS

The incidence of COM was significantly higher in the CRS group than in the control group. In a subgroup analysis, the incidence of COM in all age groups and in men and women was significantly higher in the CRS group than in the control group. More, CRS increased the risk of COM.

CONCLUSIONS

A significant association was observed between CRS and COM. This indicates that CRS patients have a high risk of developing COM.

Association between body mass index and the risk of falls: a nationwide population-based study

The association of BMI with falls differed between men and women in Korea. Obesity was associated with a greater risk of falls in women, whereas underweight seemed to increase the risk of falls compared with normal weight in men.

PURPOSE

This study examined the sex-specific association between body mass index (BMI) and falls in Korean adults using data from a large population-based survey.

METHODS

We analyzed 113,805 men and women (age ≥ 50 years) who participated in the Korean Community Health Survey in 2013. Logistic regression was used to assess the relationship between BMI and falls.

RESULTS

The mean (± standard deviation) age and BMI of all participants were 63.8 ± 9.6 years and 23.2 ± 2.9 kg/m², respectively. Among the 113,805 subjects, 19.1% and 6.7% had histories of falls and recurrent falls, respectively. The association of BMI with recurrent falls differed between men and women. The multivariable-adjusted odd ratios (ORs) for recurrent falls were 0.98 (95% confidence interval [CI] 0.86-1.12), 1.23 (1.14-1.32), and 1.51 (1.26-1.81) in women with BMIs of < 18.5, 25-29.9, and ≥ 30 kg/m², respectively, relative to those with BMIs of 18.5-24.9 kg/m². The corresponding ORs for men were 1.20 (95% CI 1.01-1.42), 1.05 (0.96-1.14), and 0.97 (0.69-1.38), respectively. Older age and low economic level were associated independently with higher ORs of recurrent falls in men and women, respectively. In addition, comorbidities, including diabetes, stroke, arthritis, osteoporosis, and asthma, correlated significantly with an increased risk of recurrent falls (all p < 0.001).

CONCLUSIONS

Obesity was associated with a greater risk of recurrent falls in women, whereas underweight seemed to be associated with a greater risk of falls in men.

Revised Korean Cough Guidelines, 2020: Recommendations and Summary statements

Cough is the most common respiratory symptom that can have various causes. It is a major clinical problem that can reduce a patient’s quality of life. Thus, clinical guidelines for the treatment of cough were established in 2014 by the cough guideline committee under the Korean Academy of Tuberculosis and Respiratory Diseases. From October 2018 to July 2020, cough guidelines were revised by members of the committee based on the first guidelines. The purpose of these guidelines is to help clinicians efficiently diagnose and treat patients with cough. This article highlights the recommendations and summary of the revised Korean cough guidelines. It includes a revised algorithm for the evaluation of acute, subacute, and chronic cough. For a chronic cough, upper airway cough syndrome (UACS), cough variant asthma (CVA), and gastroesophageal reflux disease (GERD) should be considered in differential diagnoses. If UACS is suspected, first-generation antihistamines and nasal decongestants can be used empirically. In cases with CVA, inhaled corticosteroids are recommended to improve cough. In patients with suspected chronic cough due to symptomatic GERD, proton pump inhibitors are recommended. Chronic bronchitis, bronchiectasis, bronchiolitis, lung cancer, aspiration, intake of angiotensin-converting enzyme inhibitor, intake of dipeptidyl peptidase-4 inhibitor, habitual cough, psychogenic cough, interstitial lung disease, environmental and occupational factors, tuberculosis, obstructive sleep apnea, peritoneal dialysis, and unexplained cough can also be considered as causes of a chronic cough. Chronic cough due to laryngeal dysfunction syndrome has been newly added to the guidelines.

The association between eosinophilic exacerbation and eosinophilic levels in stable COPD

Background

Blood eosinophil count may predict treatment response in patients with chronic obstructive pulmonary disease (COPD) during acute exacerbations (AE). However, the ability and thresholds of blood eosinophil counts in stable status to predict eosinophilic AECOPD have not been completely investigated.

Methods

This was a retrospective multicenter study performed January 2010 to December 2014. COPD subjects hospitalized with exacerbations, were included. Blood samples were obtained at the time of AE and stable disease at outpatient clinic before or after admission. We identified a blood eosinophil count cut-off point at stable COPD, either taken as a percentage or as absolute value, for identification of eosinophilic exacerbation.

Results

There was significant positive correlation of eosinophil counts between stable COPD and AECOPD. The best cut-off value of blood eosinophil count in stable status for the prediction of eosinophilic COPD exacerbation based on blood eosinophil count ≥ 2% was 300 cells/µL (area under the ROC curve [AUC] 0.614, P = 0.001, 39% sensitivity, 83.8% specificity). When the eosinophilic COPD exacerbation was based on blood eosinophil count ≥ 300 cells/µL, the best cut-off value of blood eosinophil count in stable status for the prediction of eosinophilic COPD exacerbation was also 300 cells/uL (AUC 0.634, P = 0.046, 45.8% sensitivity, 80.9% specificity).

Conclusions

We demonstrated association between blood eosinophil counts at stable COPD and those with AECOPD. The thresholds of blood counts at stable COPD to predict eosinophilic exacerbations was 300 cells/µL. Further and prospective studies in other populations should validate our results.

Importance of Awareness and Treatment for Diabetes in Influenza Vaccination Coverage of Diabetic Patients under 65 Years: A Population-Based Study

BACKGROUND

Influenza is a global public health problem causing considerable morbidity and mortality. Although vaccination is the most effective way to prevent infection, vaccination coverage is insufficient in people with chronic disease under 65 years, especially diabetes. The purpose of this study was to evaluate influenza vaccination coverage and identify factors associated with influenza vaccination in Korean diabetic adults under 65 years.

METHODS

Data were obtained from 24,821 subjects in the Korea National Health and Nutrition Examination Survey (2014 to 2017). Socioeconomic, health-related, and diabetic factors were investigated for their relations with influenza vaccination in diabetic patients under 65 years using univariate and multivariate analyses.

RESULTS

Among 24,821 subjects, 1,185 were diabetic patients under 65 years and their influenza vaccination rate was 36.5%. Socioeconomic (older age, female gender, non-smoker, light alcohol drinker, lower educational level, and employed status), health-related factors (lower fasting glucose and glycosylated hemoglobin level, good self-perceived health status, more comorbidities, recent health screening, more outpatient visits, and diet therapy), and diabetic factors (more awareness and getting treated) were associated with influenza vaccination. In multivariate analysis, more awareness and getting treated for diabetes were associated with influenza vaccination in diabetic patients under 65 years (odds ratio, 1.496 and 1.413; 95% confidence interval, 1.022 to 2.188 and 1.018 to 2.054, respectively).

CONCLUSION

Influenza vaccination rate was low in diabetic patients under 65 years, especially in those with unawareness and not getting treated for diabetes. Active screening and treatment for diabetes may be helpful to improve the influenza vaccination rate in these patients.

Regional emphysema score is associated with tumor location and poor prognosis in completely resected NSCLC patients

BACKGROUND

Lung cancer is a frequent comorbidity of chronic obstructive pulmonary disease (COPD). However, the local risk of developing lung cancer related to regional emphysema distribution and clinical outcome has not been investigated. Our aim was to evaluate the impact of regional emphysema score (RES) on tumor location and prognosis in non-small cell lung cancer (NSCLC) patients.

METHODS

We enrolled 457 patients who underwent curative surgery for NSCLC at seven hospitals at The Catholic University of Korea from 2014 to 2018. Emphysema was visually assessed for each lobe, with the lingula as a separate lobe. Semi-quantitative emphysema scoring was classified as follows: 0 = none, 0.5 = 1 to 10%, 1 = 11 to 25%, 2 = 26 to 50%, 3 = 51 to 75%, and 4 = 76 to 100%. An RES was given to each of the six lung zone: the upper, middle, and lower lobes in the right and left lungs.

RESULTS

There were 145 patients in the high RES (≥ 3) group and 312 in the low RES (< 3) group. The mean RES in each lobe with cancer was significantly higher than that in other lobes without cancer (0.51 vs. 0.37, P <  0.001). This group showed significantly shorter disease-free survival (P <  0.001), in addition, presence of COPD, low diffusing capacity of the lung for carbon monoxide (< 80), smoking status, and poor differentiation were more frequent in this group. Also, cancer in a lobe with a higher RES (odds ratio (OR) = 1.56; 95% confidence interval (CI:1.01-2.42; P = 0.04), pathologic stage ≥ III (OR = 2.23; 95% CI: 1.28-3.89; P <  0.001), and poor differentiation (OR = 1.99; 95% CI: 1.22-3.21; P <  0.001) were independent factors for tumor recurrence.

CONCLUSIONS

The regional severity of emphysema by visual qualification was associated with the location of lung cancer, and was an independently poor prognostic factor for tumor recurrence in completely resected NSCLC patients.

Impact of smoking amount on clinicopathological features and survival in non-small cell lung cancer

BACKGROUND

Screening for early detection of lung cancer has been performed in high-risk individuals with smoking history. However, researches on the distribution, clinical characteristics, and prognosis of these high-risk individuals in an actual cohort are lacking. Thus, the objective of this study was to retrospectively review characteristics and prognosis of patients with smoking history in an actual lung cancer cohort.

METHODS

The present study used the lung cancer cohort of the Catholic Medical Centers at the Catholic University of Korea from 2014 to 2017. Patients with non-small cell lung cancer were enrolled. They were categorized into high and low-risk groups based on their smoking history using the national lung screening trial guideline. Distribution, clinical characteristics, and survival data of each group were estimated.

RESULTS

Of 439 patients, 223 (50.8%) patients were in the high-risk group. Patients in the high-risk group had unfavorable clinical characteristics and tumor biologic features. Overall survival of the high-risk group was significantly shorter than that of the low-risk group with both early (I, II) and advanced stages (III, IV). In multivariate analysis, heavy smoking remained one of the most important poor clinical prognostic factors in patients with lung cancer. It showed a dose-dependent relationship with patients' survival.

CONCLUSIONS

High-risk individuals had poor clinical outcomes. Patients' prognosis seemed to be deteriorated as smoking amount increased. Therefore, active screening and clinical attention are needed for high-risk individuals.

Age-stratified anti-tuberculosis drug resistance profiles in South Korea: a multicenter retrospective study

BACKGROUND

The emergence of drug-resistant tuberculosis (DR-TB) is a major healthcare concern worldwide. Here, we analyzed age-related trends in DR-TB rates in South Korea.

METHODS

Drug susceptibility test results were collected from patients with culture-confirmed TB between 2015 and 2018 from eight university-affiliated hospitals. Patients were divided into three subgroups: younger (15-34 years), middle (35-59 years), and older (≥60 years) to compare drug-resistance patterns. To evaluate trends in age-stratified drug-resistance, chi-square test for linear trends was performed.

RESULTS

Among enrolled native patients aged ≥15 years, 4.1% (179/4417), 1.2% (53/4417) and 7.2% (316/4417) were multidrug-resistant TB (MDR-TB), rifampicin-mono-resistant TB (RR-TB), and isoniazid-mono-resistant TB (Hr-TB), respectively. Proportions of Hr-TB cases were 5.4% (40/734), 7.2% (114/1593), and 7.8% (162/2090) in the younger, middle and older age groups, respectively. MDR/RR-TB case rates decreased significantly with age from 8.6% (63/734) in younger age group to 3.3% (68/2090) in older age group. Fluoroquinolone resistance was highest among second-line drugs, and there were no differences in resistance to fluoroquinolones and second-line injectable drugs among the three age groups.

CONCLUSIONS

The number of MDR/RR-TB cases was highest in young patients. Effective public health interventions should include increased focus on rifampicin resistance in young patients.

Smoking is associated with pneumonia development in lung cancer patients

Background

Various host factors can promote pneumonia susceptibility of lung cancer patients. However, data about risk factors for pneumonia in lung cancer patients receiving active treatments such as chemotherapy, radiotherapy, and surgical intervention are limited. Thus, the purpose of this study was to identify risk factors for pneumonia development in lung cancer patients.

Methods

The present study used a lung cancer cohort of the Catholic Medical Center at the Catholic University of Korea from January 2015 to December 2018. Pneumonia was defined by the presence of a new or progressive infiltration on chest imaging together with any of the following: new onset purulent sputum, change in character of chronic sputum, and fever. We ruled out noninfectious infiltration such as drug or radiation toxicity and hydrostatic pulmonary edema. We especially excluded those if computed tomography revealed sharp demarcation consolidation or ground glass opacity limited radiation field.

Results

A total of 413 patients were enrolled in this study. Pneumonia occurred in 118 (28.6%) patients. The pneumonia group had significantly worse overall survival (OS) than the non-pneumonia group (456.7 ± 35.0 days vs. 813.4 ± 36.1 days, log rank p < 0.001). In patients with pneumonia, OS was shorter in ex-smokers and current smokers than in never smokers (592.0 ± 101.0 days vs. 737.0 ± 102.8 days vs. 1357.0 days, log rank p < 0.001). Age (hazard ratio [HR]: 1.046; 95% confidence interval [CI]: 1.019–1.074; p = 0.001), clinical stage IV (HR: 1.759; 95% CI: 1.004–3.083; p = 0.048), neutropenia (HR: 2.620; 95% CI: 1.562–4.396; p < 0.001], and smoking (HR: 2.040; 95% CI: 1.100–3.784; p = 0.024) were independent risk factors of pneumonia development in lung cancer patients in multivariate analysis. In subgroup analysis for patients treated with chemotherapy, age (HR: 1.043; 95% CI: 1.012–1.074; p = 0.006), neutropenia (HR: 3.199; 95% CI: 1.826–5.605; p < 0.001), and smoking (HR: 2.125; 95% CI: 1.071–4.216; p = 0.031) were independent risk factors of pneumonia development.

Conclusions

Smoking and neutropenia were risk factors affecting pneumonia development in the total group and subgroup of patients with lung cancer.

Clinical significance of anemia as a prognostic factor in non-small cell lung cancer carcinoma with activating epidermal growth factor receptor mutations

Background

Anemia is a frequent finding in cancer patients. Pre-treatment anemia is known to be associated with poor survival after surgery or stereotactic body radiation therapy of non-small cell lung cancer (NSCLC). However, little study was conducted in NSCLC with activating epidermal growth factor receptor (EGFR) mutations.

Methods

This was a multicenter retrospective study conducted in seven university teaching hospitals in the Republic of Korea from January 2009 to February 2016. A total of 290 patients were diagnosed with NSCLC harboring sensitizing EGFR mutations and treated with EGFR-tyrosine kinase inhibitor (TKI) as 1st line. Of these patients, 104 met the exclusion criteria. Pre-treatment anemia was defined according to World Health Organization criteria (Hb concentration <13 g/dL for men and <12 g/dL for women).

Results

A total of 186 patients were finally included for analysis. Of these patients, 86 (46.2%) and 100 (53.8%) patients were classified into anemia and non-anemia groups, respectively. The anemia group had shorter median overall survival (OS) than the non-anemia group [24.83 (95% CI, 17.49–32.17) months vs. 42.10 (95% CI, 31.87–52.34) months, P=0.031]. In multivariate analysis, anemia (aHR, 2.573; 95% CI, 1.122–5.901; P=0.026) was only independent factors for poor OS.

Conclusions

Our study suggests that pre-treatment anemia is a significant poor prognostic factor for OS of NSCLC patients with EGFR mutations treated with EGFR-TKI.

P4641Are coronary artery abnormalities in Kawasaki disease associated with iron deficiency anemia?

Purpose

Coronary artery abnormalities (CAA) are the most important complication of Kawasaki disease (KD). Iron deficiency anemia (IDA) is prevalent micronutrient deficiencies and its association with KD remains unknown. We hypothesized the presence of IDA could be a predictor of CAA.

Methods

This retrospective study included 173 KD patients, divided into two groups by absence (Group 1) and presence (Group 2) of CAA. The odds ratio (OR) with 95% confidence interval (CI) was calculated using a logistic regression model to estimate the association between CAA and other indicators. Due to the collinearity between the IDA indicators, each indicator was paired with anemia in 3 models.

Results

The 3 indicators of IDA, serum iron, iron saturation and ferritin, were all significantly higher in Group 1 than in Group 2. Three sets of models including anemia with iron indicators produced the odd ratio (OR) of CAA of 3.513, 3.171, and 2.256, respectively. The 3 indicators of IDA were negatively associated with CAA, by OR of 0.965, 0.914, and 0.944, respectively. The Area under the curve (AUC) of ferritin, iron saturation, serum iron, anemia, and Kobayashi score was 0.907 (95% CI, 0.851–0.963), 0.729 (95% CI, 0.648–0.810), 0.711 (95% CI, 0.629–0.793), 0.638 (95% CI, 0.545–0.731), and 0.563 (95% CI, 0.489–0.636) respectively.

Figure 1 & 3

Conclusion

The indicators of IDA, especially ferritin, were highly associated with CAA, so that they were stronger predictors compared to the Kobayashi score. The IDA indicators can be used to predict CAA development and suggest the need for early intervention.

Acknowledgement/Funding

None

Nonambipolar Transport due to Electrons with 3D Resistive Response in the KSTAR Tokamak

A small nonaxisymmetric (3D) magnetic field can induce nonambipolar transport of the particle species confined in a tokamak and thus a significant change of plasma rotation. This process can be in a favor of instability control in the region where the tokamak plasma is sufficiently collisional and resistive, as observed in the applications of n=1 resonant magnetic perturbations to the KSTAR tokamak. The plasma rotation can be globally accelerated due to radially drifting electrons and constrained to the electron root, if the radial transport is enhanced by an amplified 3D response. This mechanism is verified by a kinetically self-consistent magnetohydrodynamic modeling for both response and transport, which offers the quantitative explanations on the internal n=1 structure detected by electron-cyclotron-emission imaging and the cocurrent plasma spinning observed in the experiments.

Search for a Dark Matter-Induced Annual Modulation Signal in NaI(Tl) with the COSINE-100 Experiment

We present new constraints on the dark matter-induced annual modulation signal using 1.7 years of COSINE-100 data with a total exposure of 97.7 kg yr. The COSINE-100 experiment, consisting of 106 kg of NaI(Tl) target material, is designed to carry out a model-independent test of DAMA/LIBRA's claim of WIMP discovery by searching for the same annual modulation signal using the same NaI(Tl) target. The crystal data show a 2.7  cpd/kg/keV background rate on average in the 2-6 keV energy region of interest. Using a χ-squared minimization method we observe best fit values for modulation amplitude and phase of 0.0092±0.0067  cpd/kg/keV and 127.2±45.9  d, respectively.

Pretreatment Anterior Choroidal Artery Infarction Predicts Poor Outcome after Thrombectomy in Intracranial ICA Occlusion

BACKGROUND AND PURPOSE

Predictors of outcome after endovascular thrombectomy have not been investigated adequately in patients with intracranial ICA occlusions. This study aimed to assess the impact of anterior choroidal artery infarction in pretreatment DWI on the outcome of patients with acute intracranial ICA occlusion who underwent thrombectomy.

MATERIALS AND METHODS

This study included 113 patients with acute intracranial ICA occlusion who underwent DWI followed by thrombectomy between January 2011 and July 2016. Characteristics and outcomes were compared between the groups positive and negative for anterior choroidal artery infarction and patients with good outcomes (90-day mRS 0-2) and poor outcomes (mRS 3-6). Binary logistic regression analyses were performed to identify independent predictors of a good outcome.

RESULTS

On pretreatment DWI, anterior choroidal artery infarction was observed in 60 patients (53.1%). Good outcomes were significantly less frequent in the group positive for anterior choroidal artery infarction than in the group negative for it (25% versus 49.1%, P = .008). Parenchymal hemorrhage occurred only in the group positive for anterior choroidal artery infarction (13.3% versus 0%, P = .007). In the multivariate logistic regression analysis, independent predictors of good outcome were an absence of anterior choroidal artery infarction (OR, 0.333; 95% CI, 0.135-0.824; P = .017) and successful reperfusion (OR, 5.598; 95% CI, 1.135-27.604; P = .034).

CONCLUSIONS

Pretreatment anterior choroidal artery infarction is associated with parenchymal hemorrhage and poor outcome after thrombectomy in patients with acute intracranial ICA occlusion. In addition, the absence of anterior choroidal artery infarction and successful reperfusion were independent predictors of good outcome after thrombectomy in acute intracranial ICA occlusion.

Are patients with mild to moderate renal impairment on metformin or other oral anti-hyperglycaemic agents at increased risk of contrast-induced nephropathy and metabolic acidosis after radiocontrast exposure?

AIM

To investigate whether the use of metformin during computed tomography (CT) with radiocontrast agents increases the risk of contrast-induced nephropathy (CIN) and metabolic acidosis after CT in type 2 diabetes patients with mild to moderate renal failure.

MATERIALS AND METHODS

Patient records from January 2015 to December 2017 were reviewed retrospectively. A total of 374 patients were included in the final analysis. Of them, 157 patients received metformin, and 217 patients were taking other oral hypoglycaemic agents (OHAs) during radiocontrast administration.

RESULTS

No significant difference in CIN incidence was observed between the metformin use group and the other OHAs group (p=0.085). Metabolic acidosis after CT was seen in 91 (58%) patients who used metformin and 141 (65%) patients who were taking other OHAs. There was no relationship between metabolic acidosis after CT and the use of metformin (p=0.195). Metabolic acidosis after radiocontrast agent exposure was associated with malignant disease, low serum albumin level, and low serum total CO₂ level at baseline.

CONCLUSION

These data show that other factors, but not metformin use, are associated with metabolic acidosis after radiocontrast agent exposure in patients with reduced renal function. These data support current recommendations that there is no need to discontinue metformin before CT using radiocontrast agents in patients with mild to moderate renal failure.

First Direct Search for Inelastic Boosted Dark Matter with COSINE-100

A search for inelastic boosted dark matter (IBDM) using the COSINE-100 detector with 59.5 days of data is presented. This relativistic dark matter is theorized to interact with the target material through inelastic scattering with electrons, creating a heavier state that subsequently produces standard model particles, such as an electron-positron pair. In this study, we search for this electron-positron pair in coincidence with the initially scattered electron as a signature for an IBDM interaction. No excess over the predicted background event rate is observed. Therefore, we present limits on IBDM interactions under various hypotheses, one of which allows us to explore an area of the dark photon parameter space that has not yet been covered by other experiments. This is the first experimental search for IBDM using a terrestrial detector.

Abstract P4-06-23: Feasibility of sygeneic mice models of breast cancer for research of immune checkpoint blockades

Background: With the increasing success of immune checkpoint blockades for cancer treatment, we increasingly need well-characterized preclinical models. Syngeneic mice models (with a fully competent immune system) have advantages that they are easily established and cost less, though they do not reflect genetic complexity of human tumors. We evaluated feasibility of syngeneic mice models of breast cancer by analyzing efficacy of immune checkpoint blockade and dynamic change of tumor immune microenvironment.

Methods: We used syngeneic mice model of JC, 4T1, and EMT6 cells, which are all murine triple negative breast cancer in BALB/c mice. At the time when subcutaneous tumors reach at 50˜100mm^3, each mice models were divided into 2 groups for treatment versus no-treatment control. In the treatment group, mice version of anti-PD-1 antibody was intraperitoneally injected (q 3 days, x 6). Anti-tumor efficacy was monitored by measuring tumor volume. 'Tumor response' was defined as a case with tumor volume less than that of control group by a standard error at a determined time point. Immune microenvironment was evaluated by measuring serum cytokines (IL-2, IL-6, IL-10, IFNγ, and TNFα) with legendplex and immune cells (CD3, CD4, CD8, CD56, and FOXP3) of peripheral blood with FACS before injection of PD-1 blockade, after 1st injection, and when euthanized. Tumor-infiltrating immune cells were evaluated with FACS, when euthanized.

Results: The tumor response rate to PD-1 blockade was highest in the 4T1 model (54.5%, 6/11) compared to JC model (40%, 4/10) or EMT6 model (36.4%, 4/11). Bleeding 3 times and tumor obtainment when euthanized in each mouse were feasible for profiling of cytokines and immune cells. Although before treatment with PD-1 blockade, CD3+T cells in peripheral blood were slightly lower in 4T1 model (18.3±8.1%) than JC model (24.6±4.7%) or EMT6 model (27.9±6.3%), after injection of one dose of PD-1 blockade, CD3+T cells increased 1.5 times in 4T1 model (18.3% to 27.3%), whereas those CD3+T cells decreased slightly in JC model and EMT6 model. Dynamic changes were not observed in other subsets of peripheral immune cells in all 3 models. Serum TNFα (with statistical significance) and IFNγ (with borderline significance) were higher in responders than in non-responders or no-treatment control.

Conclusions: Syngeneic mice models of breast cancer were feasible to investigate immune checkpoint blockades and monitor dynamic change of immune microenvironment. In this regard, such models may be used to evaluate immune checkpoint blockade-based combination therapy as well.

Citation Format: Moon YW, Park N, Hur J, Pandey K, Cho YB, Kim SK, Lee SA, Son GW, Jo JM, An H-J. Feasibility of sygeneic mice models of breast cancer for research of immune checkpoint blockades [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-06-23.

Longitudinal change of FEV1 and inspiratory capacity: clinical implication and relevance to exacerbation risk in patients with COPD

Background and objective

FEV₁ is the gold standard for assessment of COPD. We compared efficacy of FEV₁, inspiratory capacity (IC), and IC to total lung capacity (TLC) ratio in the evaluation of COPD and their association with exacerbation.

Methods

We analyzed the association of dyspnea severity, quality of life status, and lung function with lung function measurements and exacerbation risk in 982 patients enrolled in the Korea COPD Subgroup Registry and Subtype Research study. Exacerbation and longitudinal lung function change were evaluated in 3 years’ follow-up.

Results

The FEV₁, IC, and IC to TLC ratio showed comparable negative correlations with dyspnea severity and quality of life status, and positive correlation with exercise capacity. In patients with >2 events/year, annual rate of change in FEV₁ and IC tended to decline more rapidly in those with FEV₁ <50% than in those with FEV₁ >50% (−14.46±19.40 mL/year vs 12.29±9.24 mL/year, P=0.213; −4.75±17.28 mL/year vs −78.05±34.16 mL/year, P=0.056 for FEV₁ and IC, respectively), without significance.

Conclusion

Longitudinal changes in IC and FEV₁ were not significantly associated with exacerbation risk.

Clinical Feasibility of Zero TE Skull MRI in Patients with Head Trauma in Comparison with CT: A Single-Center Study

BACKGROUND AND PURPOSE

Conventional MR imaging techniques cannot produce optimal images of bone structures because bone has little water and a very short T2 life span. The aim of this study was to investigate the clinical feasibility of skull MR imaging using the zero TE sequence in patients with head trauma by assessing its diagnostic image quality and quantitative measurement compared with CT images.

MATERIALS AND METHODS

Thirteen enrolled patients with head trauma were assessed using brain CT and skull MR imaging. Image quality was graded on a 5-point Likert scale to compare the 2 modalities. To evaluate quantitative analyses between the 2 imaging modalities, we measured skull thickness and normalized bone tissue signal. Interobserver reliability was assessed using weighted κ statistics and the intraclass correlation coefficient.

RESULTS

Both imaging techniques clearly depicted skull fractures in all 13 patients. The mean scores for skull MR imaging and CT were 4.65 ± 0.56 and 4.73 ± 0.45 (P = .157), respectively, with substantial interobserver agreement (P < .05). The 2 imaging modalities showed no difference in skull thickness (P = .092) and had good correlation (r ² = 0.997). The mean value of normalized bone tissue signal among the 3 layers of the skull was relatively consistent (P = .401) with high interobserver agreement (P < .001).

CONCLUSIONS

Zero TE skull MR imaging has diagnostic image quality comparable with that of CT images. It also provides consistent results on the quantitative measurement of cortical bone with CT images.

Protective effects of diphenyleneiodonium, an NADPH oxidase inhibitor, on lipopolysaccharide-induced acute lung injury

NADPH oxidase (NOX) plays an important role in inflammatory response by producing reactive oxygen species (ROS). The inhibition of NOX has been shown to induce anti-inflammatory effects in a few experimental models. The aim of this study was to investigate the effects of diphenyleneiodonium (DPI), a NOX inhibitor, on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in a rat model. Sprague-Dawley rats were intraperitoneally administered by DPI (5 mg/kg) 30 minutes after intratracheal instillation of LPS (3 mg/kg). After 6 hours, bronchoalveolar lavage fluid (BALF) and lung tissue were collected. The NOX activity in lung tissue was significantly increased in LPS-treated rats. It was significantly attenuated by DPI. DPI-treated rats showed significant reduction in the intracellular ROS, the number of inflammatory cells, and cytokines (TNF-α and IL-6) in BALF compared with LPS-treated rats. In lung tissue, DPI-treated rats showed significantly decreased malondialdehyde content and increased activity of glutathione peroxidase and superoxide dismutase compared with LPS-treated rats. Lung injury score, myeloperoxidase activity, and inducible nitric oxide synthase expression were significantly decreased in DPI-treated rats compared with LPS-treated animals. Western blotting analysis demonstrated that DPI significantly suppressed LPS-induced activation of NF-κB and ERK1/2 and SAPK/JNK in MAPK pathway. Our results suggest that DPI may have protective effects on LPS-induced ALI thorough anti-oxidative and anti-inflammatory effects which may be due to inactivation of the NF-κB, ERK1/2, and SAPK/JNK pathway. These results suggest the therapeutic potential of DPI as an anti-inflammatory agent in ALI.

Direct and Indirect Costs of Chronic Obstructive Pulmonary Disease in Korea

Background

Understanding the burden of disease is important to establish cost-effective treatment strategies and to allocate healthcare resources appropriately. However, little reliable information is available regarding the overall economic burden imposed by chronic obstructive pulmonary disease (COPD) in Korea.

Methods

This study is a multicenter observational research on the COPD burden in Korea. Total COPD costs were comprised of three categories: direct medical, direct non-medical, and indirect costs. For direct medical costs, institutional investigation was performed at 13 medical facilities mainly based on the claims data. For direct non-medical and indirect costs, site-based surveys were administered to the COPD patients during routine visits. Total costs were estimated using the COPD population defined in the recent report.

Results

The estimated total costs were approximately 1,245 million US dollar (1,408 billion Korean won). Direct medical costs comprised approximately 20% of the total estimated costs. Of these, formal medical costs held more than 80%. As direct non-medical costs, nursing costs made up the largest percentage (39%) of the total estimated costs. Costs for COPD-related loss of productivity formed four fifths of indirect costs, and accounted for up to 33% of the total costs.

Conclusion

This study shows for the first time the direct and indirect costs of COPD in Korea. The total costs were enormous, and the costs of nursing and lost productivity comprised approximately 70% of total costs. The results provide insight for an effective allocation of healthcare resources and to inform establishment of strategies to reduce national burden of COPD.

Identification of a new HLA-A*11 allele, A*11:251N

The new allele, A*11:251N, differs from A*11:01:01 by insertion of two nucleotides at position 204-205.

Skin photorejuvenation effects of light-emitting diodes (LEDs): a comparative study of yellow and red LEDs in vitro and in vivo

BACKGROUND

Red-coloured light-emitting diodes (LEDs) can improve skin photorejuvenation and regeneration by increasing cellular metabolic activity.

AIM

To evaluate the effectiveness of visible LEDs with specific wavelengths for skin photorejuvenation in vitro and in vivo.

METHODS

Normal human dermal fibroblasts (HDFs) from neonatal foreskin were cultured and irradiated in vitro by LEDs at different wavelengths (410-850 nm) and doses (0-10 J/cm(2) ). In vivo experiments were performed on the skin of hairless mice. Expression of collagen (COL) and matrix metalloproteinases (MMPs) was evaluated by semi-quantitative reverse transcription PCR (semi-qRT-PCR), western blotting and a procollagen type I C-peptide enzyme immunoassay (EIA). Haematoxylin and eosin and Masson trichrome stains were performed to evaluate histological changes.

RESULTS

In HDFs, COL I was upregulated and MMP-1 was downregulated in response to LED irradiation at 595 ± 2 and 630 ± 8 nm. In the EIA, a peak result was achieved at a dose of 5 J/cm(2) with LED at 595 ± 2 nm. In vivo, COL I synthesis was upregulated in a dose-dependent manner to both 595 and 630 nm LED irradiation, and this effect was prolonged to 21 days after a single irradiation with a dose of 100 J/cm(2) . These histological changes were consistent with the results of semi-qRT-PCR and western blots.

CONCLUSION

Specific LED treatment with 595 ± 2 and 630 ± 8 nm irradiation was able to modulate COL and MMPs in skin, with the effects persisting for at least 21 days after irradiation. These findings suggest that yellow and red LEDs might be useful tools for skin photorejuvenation.

Risk factors for the discontinuation of roflumilast in patients with chronic obstructive pulmonary disease

Introduction

Roflumilast is a phosphodiesterase-4 inhibitor, which can decrease exacerbation in patients with chronic obstructive pulmonary disease (COPD). However, adverse effects are a major barrier to medication use, and little is known regarding the risk factors for discontinuation of roflumilast in COPD patients.

Method

A search of the clinical databases identified all patients who were prescribed roflumilast between December 2012 and April 2015 in the four hospitals of The Catholic University of Korea, Korea. The study subjects were limited to patients who had taken 500 μg of roflumilast. We studied the factors associated with drug discontinuation and drug adverse events by univariate and multivariate analyses.

Results

Among 154 eligible patients, 54 (35.1%) discontinued their roflumilast prescription. Most patients were elderly, male, current or former smokers, and had moderate-to-severe airflow limitation. Low–body mass index (BMI) patients were more likely to undergo drug discontinuation (1-unit decrease in BMI: odds ratio [OR] =1.165, p=0.006; BMI <23 kg/m²: OR =2.960, p=0.004). Fifty-five patients (35.7%) had adverse events. Loss of appetite, diarrhea, nausea, headache, and weight loss were the most frequent adverse events. Low-BMI patients were more likely to experience adverse events (1-unit decrease in BMI: OR =1.151, p=0.010; BMI <23 kg/m²: OR =2.644, p=0.009).

Conclusions

The patient discontinuation and adverse events rates in this study were higher than in previous randomized controlled studies. Discontinuation of roflumilast in ethnic Koreans is more likely to occur in low-BMI patients. In a clinical setting, low-BMI patients can more easily discontinue roflumilast; clinicians should, therefore, provide greater care for these patients.

Factors Related to the Diagnostic Yield of Flexible Bronchoscopy without Guidance in Bronchoscopically Invisible Peripheral Lung Lesions

BACKGROUND

We aimed to analyze the factors predicting the diagnostic performance of flexible bronchoscopy without guidance in peripheral lung lesions that are endoscopically invisible.

METHODS

This was a retrospective study conducted in St. Paul's Hospital, The Catholic University of Korea, between January 2007 and March 2013. We included all patients who received bronchoscopy during this period. The analyzed variables were age, sex, the etiology of the lesion, lesion size, distance from the pleura, and presence of the bronchus sign. We used multiple logistic regression analysis to identify the significant independent factors associated with diagnostic yield.

RESULTS

We included 151 patients in this study. The overall diagnostic yield was 58.3%. The sensitivity was 43.2% for malignant disease and 78.1% for benign disease. The benign lung lesions (p<0.001), lesion size (p=0.015), presence of the exposed type of bronchus sign (p<0.001), and presence of cavitary lung lesions (p=0.005) were factors influencing the yield of flexible bronchoscopy by univariate analysis. In a multivariate logistic regression analysis, the exposed type of bronchus sign and benign lung lesions were independent predicting factors (odds ratio [OR]: 27.95; 95% confidence interval [CI], 7.56-103.32; p<0.001 and OR, 4.91; 95% CI, 1.76-13.72; p=0.002).

CONCLUSION

The presence of the exposed type of bronchus sign and benign lung lesions are determining factors of the diagnostic yield in flexible bronchoscopy in evaluating peripheral lesions that are not endoscopically visible.