Vitamin C is a well-known antioxidant with antiviral, anticancer, and anti-inflammatory properties based on its antioxidative function. Aptamin C, a complex of vitamin C with its specific aptamer, has been reported to maintain or even enhance the efficacy of vitamin C while increasing its stability. To investigate in vivo distribution of Aptamin C, Gulo knockout mice, which, like humans, cannot biosynthesize vitamin C, were administered Aptamin C orally for 2 and 4 weeks.The results showed higher vitamin C accumulation in all tissues when administered Aptamin C, especially in the spleen. Next, the activity of natural killer (NK) cells were conducted. CD69, a marker known for activating for NK cells, which had decreased due to vitamin C deficiency, did not recover with vitamin C treatment but showed an increasing with Aptamin C. Furthermore, the expression of CD107a, a cell surface marker that increases during the killing process of target cells, also did not recover with vitamin C but increased with Aptamin C. Based on these results, when cultured with tumor cells to measure the extent of tumor cell death, an increase in tumor cell death was observed. To investigate the signaling mechanisms and related molecules involved in the proliferation and activation of NK cells by Aptamin C showed that Aptamin C treatment led to an increase in intracellular STAT3 activation. In conclusion, Aptamin C has a higher capability to activate NK cells and induce tumor cell death compared to vitamin C and it is mediated through the activation of STAT3.

Objectives: . This study investigated the 8-year incidence and progression of hearing loss (HL) and its types and examined the risk factors for changes in HL. Methods: . This longitudinal cohort study analyzed data from the Korean Genome and Epidemiology Study (KoGES), an ongoing, prospective, community-based cohort study that has been conducted since 2001. Altogether, 1,890 residents of urban areas in Korea aged 45–75 years at time 1 (baseline) were included in the study. Pure-tone audiometry (PTA) testing was performed twice, at time 1 (2008–2009) and time 2 (2015–2018, follow-up), 8 years apart. HL grades were defined as seven mutually exclusive categories following the revised World Health Organization classification. Incidence was defined as PTA >20 dB HL in the better ear at time 2 among those without HL at time 1. Progression was defined as the progressive deterioration of HL among those with HL at time 1. The three types of HL constituted sensorineural (SNHL), conductive, and mixed HL. Results: . At time 1, 36.40% of patients were diagnosed with HL, which increased to 51.64% at time 2. The 8-year incidence of HL was 27.20%, and progressive deterioration of HL occurred in 23.11% of those with HL. SNHL was the most common type of HL, and its prevalence markedly increased at time 2. Multivariate analysis demonstrated that the incidence of HL was significantly associated with increasing age, male sex (odds ratio [OR], 1.73; 95% confidence interval [CI], 1.07–2.81), and diabetes mellitus (OR, 1.43; 95% CI, 1.04–1.96). Alcohol consumption was a risk factor for HL deterioration among those with HL at time 1. Conclusion . The prevalence and deterioration of HL were extremely high among older adults, and age was the strongest risk factor for these changes. Therefore, timely screening and intervention are necessary to prevent HL and delay its deterioration among older adults.

Background/Aims: Epstein-Barr virus (EBV) and Helicobacter pylori (HP) coinfection may synergistically induce severe inflammatory responses in the stomach tissue, increasing the risk of developing gastric cancer. We aimed to analyze the effect of EBV and HP coinfection on the clinicopathologic features and prognosis of gastric cancer, as well as to evaluate the role of EBV infection in non-gastric carcinoma with lymphoid stroma (non-GCLS). Methods: Overall, 956 patients who underwent surgery for gastric cancer between September 2014 and August 2015 were eligible and divided into groups, according to GCLS morphology, EBV infection, and HP infection. Clinicopathologic characteristics and oncologic outcomes were analyzed retrospectively. Results: EBV and HP coinfection was significantly associated with male sex, proximal location, GCLS morphology, and equivocal p53 expression (p<0.001). Multivariate analysis revealed that EBV infection alone (hazard ratio [HR], 0.362; 95% CI, 0.131 to 0.996; p=0.049) and lower third location (HR, 0.624; 95% CI, 0.413 to 0.943; p=0.025) were inversely correlated with overall survival. During median follow-up period of 72 months, overall survival rate was not significantly different between the EBV and HP coinfection group and others (97.6% vs 86.8%, log-rank p=0.144). In non-GCLS patients (n=920), overall survival rate was not significantly different between the EBV infection group and others (96.9% vs 86.4%, log-rank p=0.126). Conclusions EBV and HP coinfection is not an independent prognostic factor for gastric cancer. EBV infection status, regardless of HP infection, affects the clinicopathologic features of all types of gastric cancer. However, it does not lead to a significant difference in overall survival of nonGCLS patients.

Background: There is a need to update the cardiovascular (CV) Sequential Organ Failure Assessment (SOFA) score to reflect the current practice in sepsis. We previously proposed the modified CV SOFA score from data on blood pressure, norepinephrine equivalent dose, and lactate as gathered from emergency departments. In this study, we externally validated the modified CV SOFA score in multicenter intensive care unit (ICU) patients. Methods: A multicenter retrospective observational study was conducted on ICU patients at six hospitals in Korea. We included adult patients with sepsis who were admitted to ICUs. We compared the prognostic performance of the modified CV/total SOFA score and the original CV/total SOFA score in predicting 28-day mortality. Discrimination and calibration were evaluated using the area under the receiver operating characteristic curve (AUROC) and the calibration curve, respectively. Results: We analyzed 1,015 ICU patients with sepsis. In overall patients, the 28-day mortality rate was 31.2%. The predictive validity of the modified CV SOFA (AUROC, 0.712; 95% confidence interval [CI], 0.677–0.746; P < 0.001) was significantly higher than that of the original CV SOFA (AUROC, 0.644; 95% CI, 0.611–0.677). The predictive validity of modified total SOFA score for 28-day mortality was significantly higher than that of the original total SOFA (AUROC, 0.747 vs. 0.730; 95% CI, 0.715–0.779; P = 0.002). The calibration curve of the original CV SOFA for 28-day mortality showed poor calibration. In contrast, the calibration curve of the modified CV SOFA for 28-day mortality showed good calibration. Conclusion In patients with sepsis in the ICU, the modified SOFA score performed better than the original SOFA score in predicting 28-day mortality.

OBJECTIVES: We estimated the population prevalence of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including unreported infections, through a Korea Seroprevalence Study of Monitoring of SARS-CoV-2 Antibody Retention and Transmission (K-SEROSMART) in 258 communities throughout Korea. METHODS: In August 2022, a survey was conducted among 10,000 household members aged 5 years and older, in households selected through two stage probability random sampling. During face-to-face household interviews, participants self-reported their health status, COVID-19 diagnosis and vaccination history, and general characteristics. Subsequently, participants visited a community health center or medical clinic for blood sampling. Blood samples were analyzed for the presence of antibodies to spike proteins (anti-S) and antibodies to nucleocapsid proteins (anti-N) SARS-CoV-2 proteins using an electrochemiluminescence immunoassay. To estimate the population prevalence, the PROC SURVEYMEANS statistical procedure was employed, with weighting to reflect demographic data from July 2022. RESULTS: In total, 9,945 individuals from 5,041 households were surveyed across 258 communities, representing all basic local governments in Korea. The overall population-adjusted prevalence rates of anti-S and anti-N were 97.6% and 57.1%, respectively. Since the Korea Disease Control and Prevention Agency has reported a cumulative incidence of confirmed cases of 37.8% through July 31, 2022, the proportion of unreported infections among all COVID-19 infection was suggested to be 33.9%. CONCLUSIONS The K-SEROSMART represents the first nationwide, community-based seroepidemiologic survey of COVID-19, confirming that most individuals possess antibodies to SARS-CoV-2 and that a significant number of unreported cases existed. Furthermore, this study lays the foundation for a surveillance system to continuously monitor transmission at the community level and the response to COVID-19.

Background: Arsenic trioxide (ATO) is the standard treatment for relapsed acute promyelocytic leukemia (APL). However, consensus on post-remission therapies is still lacking. Methods: We evaluated 52 patients who experienced relapse following initial treatment of APL between 2000 and 2019 at Catholic Hematology Hospital. Among them, 41 patients received reinduction treatment, 30 with ATO-based regimen, whereas 11 with conventional intensive chemotherapy (IC). Results: The ATO reinduction group showed a significantly higher second molecular complete remission (mCR2) rate, superior neutrophil and platelet recovery, and a lower infection rate than the IC reinduction group. No significant differences were observed in survival outcomes after post-remission treatment among the ATO-based (N=19), autologous (N=12), and allogeneic (N=6) hematopoietic stem cell transplantation (HSCT) groups. In the ATO-based and autologous HSCT groups, among patients with mCR2 after ATO reinduction, nine and five patients experienced a second relapse, respectively (50.7% vs. 41.7%, P =0.878). Among these patients, seven received salvage allogeneic HSCT; six remained alive. The other seven patients received ATO without HSCT. Five died from disease progression, and two survived and have been in mCR2 since. Conclusion Post-remission treatment outcomes of patients with relapsed APL were not significantly different, regardless of the treatment option, suggesting the feasibility of ATO-based treatment without HSCT in mCR2. Allogeneic HSCT may be an effective salvage treatment modality for patients with a second relapse. Owing to a few cases of relapsed APL, multicenter prospective studies may help elucidate the efficacy of each post-remission treatment.

Background: The Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines for chronic obstructive pulmonary disease (COPD) recommend considering patient preference when choosing an inhaler device. However, few studies have assessed both inhaler satisfaction and factors associated with high inhaler satisfaction. Therefore, we assessed inhaler satisfaction and determinants of high satisfaction in Korean COPD patients. Methods: COPD patients were prospectively enrolled from January 2018 to November 2019. The 308 inhalers used by the 261 participants in this study included dry powder inhalers (Turbuhaler, Breezhaler, Ellipta, Diskus, and Genuair), a soft mist inhaler (Respimat), and pressurized metered dose inhalers (pMDIs). Inhaler satisfaction was assessed by the Feeling of Satisfaction with Inhaler (FSI-10) questionnaire. High inhaler satisfaction was defined as an FSI-10 ≥ 43. Results: Among 261 COPD patients, 163 (62.5%) were highly satisfied with their inhaler device. The rates of high inhaler satisfaction for Turbuhaler, Breezhaler, Ellipta, Diskus, Genuair, Respimat, and pMDI usage were 40.0%, 67.2%, 66.7%, 50.0%, 55.6%, 63.4%, and 45.0%, respectively (P = 0.215). In univariate analyses, higher body mass index, non-current smoker, GOLD grades I and II, a modified Medical Research Council (mMRC) score < 2, lower inhaler puff burden, once daily usage of inhaler, and good inhaler adherence were associated with high inhaler satisfaction. In multivariate analyses, an mMRC score < 2, and good inhaler adherence were independently associated with high inhaler satisfaction. Conclusion High inhaler satisfaction was associated with dyspnea symptom and good inhaler adherence in COPD patients. Effective strategies are needed including appropriate inhaler device selection, consideration of patient preference, and repeated inhaler education to improve patient satisfaction of inhalers.

Background/Aims: Idiopathic multicentric Castleman disease (iMCD) comprises approximately 30% of all cases of Castleman disease. It is characterized by constitutional symptoms, enlarged lymph nodes at multiple anatomical sites, and laboratory test abnormalities, which are primarily related to the overproduction of interleukin 6 (IL-6). Siltuximab is a human-mouse chimeric immunoglobulin G1κ monoclonal antibody against human IL-6. In view of the limited treatment options for iMCD, this study aimed to evaluate the efficacy and safety of siltuximab in the management of this condition. Methods: In this real-world retrospective study, we administered siltuximab to 15 patients with iMCD who previously received conventional chemotherapy and/or steroid pulse therapy. The median time to a durable symptomatic response was 22 days (range, 17 to 56). The serum hemoglobin and albumin levels and erythrocyte sedimentation rates significantly normalized after the first 3 months of siltuximab treatment. Lymph node involution, assessed using imaging, was relatively gradual, demonstrating a complete or partial response at 6 months. Results: On an average, the improvements in clinical, laboratory, and radiologic parameters of iMCD in responders were observed after one, three, and eight cycles of siltuximab treatment, respectively. Siltuximab demonstrated a favorable safety profile, and prolonged treatment was well-tolerated. Conclusions Despite the small sample size of the present study, the results are encouraging and demonstrate the potential of siltuximab as the first-line treatment of iMCD. Further large multicenter studies are needed to evaluate the clinical outcomes and adverse events associated with siltuximab.

Background: The presence of the bronchus sign on chest computed tomography is associated with an increased diagnostic yield of radial probe endobronchial ultrasound– guided transbronchial lung biopsy (RP-EBUS-TBLB). However, the utility of RP-EBUS-TBLB for bronchus sign negative peripheral pulmonary lesions (PPLs) remains unknown. We investigated the utility of RP-EBUS-TBLB in bronchus sign negative PPLs. Methods: We retrospectively reviewed data from 109 patients who underwent RP-EBUS for bronchus sign negative PPLs from January 2019 to August 2020. TBLB was performed using RP-EBUS with a guide sheath and without fluoroscopy. The EBUS visualization and TBLB diagnostic yields were assessed. Multivariable logistic regression analyses were used to identify factors affecting the EBUS visualization and diagnostic yields. Results: The EBUS visualization yield was 74.1% (68/109). Of the 109 lung lesions, 92 were definitively diagnosed. The overall diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 50.5% (55/109), 34.9% (29/83), 100% (26/26), 100% (29/29), and 32.5% (26/80), respectively. In multivariable analyses, the size of the lesion (≥ 20 mm; odds ratio [OR], 2.62; 95% confidence interval [CI], 1.16–5.93; P = 0.021) and the distance from the pleura (> 10 mm; OR, 2.37; 95% CI, 1.02–5.52; P = 0.045) were associated with EBUS visualization. Regarding diagnostic yield, having the probe within the lesion (OR, 28.50; 95% CI, 6.26–129.85; P < 0.001) and a solid lesion (OR, 14.58; 95% CI, 2.64–80.38; P = 0.002) were associated with diagnostic success. Pneumothorax and hemoptysis occurred in 3.7% (4/109) and 0.9% (1/109), respectively, of the patients. Conclusion RP-EBUS-TBLB using a GS can be considered a diagnostic method in bronchus sign negative solid PPLs. Having the probe within the lesion and a solid lesion were important for diagnostic success. Complication rates were acceptable.

Objective: The relation between female emotional laborers’ sleep quality and autonomic nervous system activity was investigated. Methods: Thirty-three subjects’ heart rate variability (HRV) data and results of self-reported scale on sleep, depression, anxiety and suicidality, were collected. Subjects were classified into good sleeper (GS) and poor sleeper (PS) groups relying on sleep quality. Changes of HRV between working time and resting time in each group were compared. Results: The PS group showed significantly lower difference in root mean square of successive differences (RMSSD), percentage of successive normal-to-normal intervals that differ by more than 50 ms (pNN50), and natural logarithm high-frequency (LnHF) when they were working as compared to when they were resting, which means decreased function of the parasympathetic nervous system (PNS). Repeated measures analysis of covariance showed that the group effect was significant only for LnHF, with score of depression scale as a covariate. Conclusion Female emotional laborers who complain of sleep difficulty may have decreased function of the PNS. Therefore, good sleep quality is essential for maintaining and promoting mental and physical health of women engage in emotional labor.