Purpose: This retrospective cohort study aimed to investigate the association between the use of pain medications with varying cyclooxygenase-2 (COX-2) selectivity and the incidence of endometriosis (EMS) in women. Materials and Methods: Medical records from January 1, 1994, to December 31, 2022, were retrospectively analyzed. The cohort included 33406 patients diagnosed with any pain-related condition who were prescribed either selective COX-2 inhibitors or nonsteroidal anti-inflammatory drugs (NSAIDs). Patients were followed for up to 5 years from the cohort entry date. The incidence of EMS was compared between the two medication groups using Cox proportional hazards models, adjusting for confounding factors such as age, past drug use, and prior diagnosis. Results: The incidence rates of EMS were 3.00 per 1000 person-years in the COX-2 inhibitor group and 3.97 per 1000 person-years in the NSAIDs group. After adjustment for confounders, the hazard ratio for EMS incidence in the COX-2 inhibitor group compared to the NSAIDs group was 0.77 [95% confidence interval (CI), 0.63 to 0.93; p<0.01], indicating a significantly lower risk in the COX-2 inhibitor group. Subgroup analysis revealed that this association was particularly significant in younger women aged 20– 44 years, with a hazard ratio of 0.71 (95% CI, 0.54 to 0.95; p<0.05) in this age group. Conclusion The findings suggest that COX-2 inhibitors may reduce the incidence of EMS compared to traditional NSAIDs, highlighting their potential as a strategic option for managing EMS, particularly among younger women. Further prospective studies are needed to confirm these findings.

Background: Malnutrition exacerbates the prognosis of numerous diseases; however, its specific impact on severe coronavirus disease 2019 (COVID-19) outcomes remains insufficiently explored. Methods: This multicenter study in Korea evaluated the nutritional status of 1,088 adults with severe COVID-19 using the Geriatric Nutritional Risk Index (GNRI) based on serum albumin levels and body weight. The patients were categorized into two groups: GNRI >98 (no-risk) and GNRI ≤98 (risk). Propensity score matching, adjusted for demographic and clinical variables, was conducted. Results: Of the 1,088 patients, 642 (59%) were classified as at risk of malnutrition. Propensity score matching revealed significant disparities in hospital (34.3% vs. 19.4%, p<0.001) and intensive care unit (ICU) mortality (31.5% vs. 18.9%, p<0.001) between the groups. The risk group was associated with a higher hospital mortality rate in the multivariate Cox regression analyses following propensity score adjustment (hazard ratio [HR], 1.64; p=0.001). Among the 670 elderly patients, 450 were at risk of malnutrition. Furthermore, the risk group demonstrated significantly higher hospital (52.1% vs. 29.5%, p<0.001) and ICU mortality rates (47.2% vs. 29.1%, p<0.001). The risk group was significantly associated with increased hospital mortality rates in the multivariate analyses following propensity score adjustment (HR, 1.66; p=0.001). Conclusion Malnutrition, as indicated by a low GNRI, was associated with increased mortality in patients with severe COVID-19. This effect was also observed in the elderly population. These findings underscore the critical importance of nutritional assessment and effective interventions for patients with severe COVID-19.

Background: The development of frailty at hospital discharge affects the clinical outcomes in severe coronavirus disease 2019 (COVID-19) survivors who had no frailty before hospitalization. We aimed to describe the prevalence of new frailty using the clinical frailty scale (CFS) and evaluate its associated factors in patients with severe COVID-19 without pre-existing frailty before hospitalization. Methods: We performed a secondary analysis of clinical data from a nationwide retrospective cohort collected from 22 hospitals between January 1, 2020 and August 31, 2021. The patients were at least 19 years old and survived until discharge after admission to the intensive care unit (ICU) because of severe COVID-19. Development of new frailty was defined as a CFS score ≥5 at hospital discharge. Results: Among 669 severe COVID-19 survivors without pre-existing frailty admitted to the ICU, the mean age was 65.2±12.8 years, 62.5% were male, and 50.2% received mechanical ventilation (MV). The mean CFS score at admission was 2.4±0.9, and new frailty developed in 27.8% (186/483). In multivariate analysis, older age, cardiovascular disease, CFS score of 3–4 before hospitalization, increased C-reactive protein level, longer duration of corticosteroid treatment, and use of MV and extracorporeal membrane oxygenation were identified as factors associated with new-onset frailty. Conclusion Our study suggests that new frailty is not uncommon and is associated with diverse factors in survivors of severe COVID-19 without pre-existing frailty.

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease that culminates in respiratory failure and death due to irreversible scarring of the distal lung. While initially considered a chronic inflammatory disorder, the aberrant function of the alveolar epithelium is now acknowledged as playing a central role in the pathophysiology of IPF. This study aimed to investigate the regenerative capacity of alveolar type 2 (AT2) cells using IPF-derived alveolar organoids and to examine the effects of disease progression on this capacity. Methods: Lung tissues from three pneumothorax patients and six IPF patients (early and advanced stages) were obtained through video-assisted thoracoscopic surgery and lung transplantation. HTII-280+ cells were isolated from CD31-CD45-epithelial cell adhesion molecule (EpCAM)+ cells in the distal lungs of IPF and pneumothorax patients using fluorescence-activated cell sorting (FACS) and resuspended in 48-well plates to establish IPF-derived alveolar organoids. Immunostaining was used to verify the presence of AT2 cells. Results: FACS sorting yielded approximately 1% of AT2 cells in early IPF tissue, and the number decreased as the disease progressed, in contrast to 2.7% in pneumothorax. Additionally, the cultured organoids in the IPF groups were smaller and less numerous compared to those from pneumothorax patients. The colony forming efficiency decreased as the disease advanced. Immunostaining results showed that the IPF organoids expressed less surfactant protein C (SFTPC) compared to the pneumothorax group and contained keratin 5+ (KRT5+) cells. Conclusion This study confirmed that the regenerative capacity of AT2 cells in IPF decreases as the disease progresses, with IPF-derived AT2 cells inherently exhibiting functional abnormalities and altered differentiation plasticity.

Purpose: This retrospective cohort study aimed to investigate the association between the use of pain medications with varying cyclooxygenase-2 (COX-2) selectivity and the incidence of endometriosis (EMS) in women. Materials and Methods: Medical records from January 1, 1994, to December 31, 2022, were retrospectively analyzed. The cohort included 33406 patients diagnosed with any pain-related condition who were prescribed either selective COX-2 inhibitors or nonsteroidal anti-inflammatory drugs (NSAIDs). Patients were followed for up to 5 years from the cohort entry date. The incidence of EMS was compared between the two medication groups using Cox proportional hazards models, adjusting for confounding factors such as age, past drug use, and prior diagnosis. Results: The incidence rates of EMS were 3.00 per 1000 person-years in the COX-2 inhibitor group and 3.97 per 1000 person-years in the NSAIDs group. After adjustment for confounders, the hazard ratio for EMS incidence in the COX-2 inhibitor group compared to the NSAIDs group was 0.77 [95% confidence interval (CI), 0.63 to 0.93; p<0.01], indicating a significantly lower risk in the COX-2 inhibitor group. Subgroup analysis revealed that this association was particularly significant in younger women aged 20– 44 years, with a hazard ratio of 0.71 (95% CI, 0.54 to 0.95; p<0.05) in this age group. Conclusion The findings suggest that COX-2 inhibitors may reduce the incidence of EMS compared to traditional NSAIDs, highlighting their potential as a strategic option for managing EMS, particularly among younger women. Further prospective studies are needed to confirm these findings.

Background: Residential smoking cessation therapy programs offer intensive treatment for heavy smokers who struggle to quit independently, particularly those with high nicotine dependence and health conditions that necessitate urgent cessation. While previous studies have established the effectiveness of such programs and identified various factors influencing smoking cessation success, it remains unclear how changes in smokers’ thoughts and attitudes following residential therapy correlate with their ability to quit smoking. We investigated the relationship between smoking cessation-related characteristics, smoking-related psychological status, and participants’ smoking cessation success after a residential smoking cessation therapy program. Methods: From January 2017 to December 2018, 291 participants completed the program. All participants completed questionnaires on smoking cessation-related characteristics and smoking-related psychological status before the program and on the 5th day. Six months later, smoking cessation success was assessed using a urine cotinine test. Results: After 6 months, 222 participants successfully quit smoking, while 69 failed. The success and failure groups exhibited statistically significant differences in age, marital status, total smoking duration, stress, and emotion regulation strategies. Participants who used ineffective emotion regulation strategies more frequently had a lower rate of smoking cessation success (odds ratio [OR], 0.969; 95% confidence interval [CI], 0.948–0.991). Moreover, an increase in the perception of the negative effects of smoking cessation (OR, 0.982; 95% CI, 0.967–0.997) and smoking temptation (OR, 0.960; 95% CI, 0.929–0.993) was associated with higher cessation success. Conclusion Emotion regulation strategies, perceptions of the effects of smoking cessation, and smoking temptation were associated with successful smoking cessation.

Background: The Rapid-O2 oxygen insufflation device® (Rapid-O2) was designed primarily for rescue oxygenation in cannot intubate, cannot oxygenate (CICO) events; thus, hypercapnia is inevitable. Rapid-O2 was modified to enhance ventilation using the Venturi effect during expiration. Methods: To determine the most effective combination of inner catheters (20 gauge [G], 18 G, 16 G, 14 G, and 2-mm inner diameter [ID] transtracheal catheter [TTC]) and insufflation catheters (16 G, 14 G, and 2-mm ID TTC) for achieving optimum ventilation, insufflating and expiratory flows were measured at an oxygen flow rate of 15 L/min. The insufflating and expiratory pressures were measured at 6–15 L/min. The flows and pressures were measured using a gas flow analyzer. The insufflating and expiratory times were measured using a trachea-lung model to obtain minute volumes. To assess the improvement by modifying the Rapid-O2, minute volumes were measured using the Rapid-O2. Results: The most appropriate inner catheter was 18 G. The insufflating pressures ranged from 97 (2-mm ID TTC) to 377 cmH2O (16 G) at 15 L/min. During expiration, similar negative pressures of 50 cmH2O were measured in the insufflation catheters at 15 L/min. At lung compliance of 100 ml/cmH2O, the minute volumes through a 2-mm ID and 14 G insufflation catheters were 7.0 and 5.37 L/min, respectively, at 15 L/min. The minute volumes were significantly greater in modified Rapid-O2. Conclusions Modified Rapid-O2 provided sufficient minute volumes in adults using a 14 G or 2-mm ID insufflation catheter at 15 L/min, demonstrating its potential for ventilation in CICO events.

Background: The efficacy of high-flow nasal oxygenation (HFNO) in improving oxygenation is influenced by several factors, and its effectiveness is not always guaranteed. Therefore, we aimed to compare the effects of HFNO and standard low-flow nasal oxygenation during rigid bronchoscopy in the apneic patients. Methods: All patients were administered general anesthesia with full muscle relaxation and were randomly assigned to receive either HFNO (HFNO group) or standard low-flow oxygenation (Standard group). The study endpoints included the lowest peripheral oxygen saturation (SpO2), hypoxemia-related surgical interruptions (SpO2 ≤ 94%), and changes in arterial oxygen tension (PaO2) and carbon dioxide tension (PaCO2) during the apnea period for rigid bronchoscopy. Results: A total of 53 patients completed the study. No significant differences were found between the HFNO and the Standard groups in the lowest SpO2 levels (median [Q1, Q3]; 99 [98, 100]% vs. 98 [94, 100]%, P = 0.059) and in the increase rate of PaCO2 (mean ± standard deviation [SD]; 1.6 ± 0.7 mmHg/min vs. 2.0 ± 0.8 mmHg/min, P = 0.064). However, the HFNO group had fewer patients with hypoxemia-related surgical interruptions than the Standard group (1 [3.8%] vs. 8 [29.6%], P = 0.024) and exhibited an attenuated decline rate in PaO2 (median [Q1, Q3]: 4.6 [0.0, 7.9] mmHg/min vs. 10.5 [6.4, 12.9] mmHg/min, P = 0.005). Conclusions While HFNO did not enhance the lowest SpO2 levels in comparison with standard low-flow oxygenation, it did reduce hypoxemia-related surgical interruptions with an attenuated decline in PaO2. Therefore, HFNO has considerable clinical efficacy for rigid bronchoscopy.

Background: Skipping breakfast is associated with an increased risk of chronic inflammatory diseases. This study aimed to examine the association between breakfast-eating habits and inflammation, using high-sensitivity C-reactive protein (hs-CRP) as a marker. Methods: A total of 4,000 Korean adult males with no history of myocardial infarction, angina, stroke, diabetes, rheumatoid arthritis, cancer, or current smoking were included. Data from the 2016–2018 Korea National Health and Nutrition Examination Survey were used for analysis. The frequency of breakfast consumption was assessed through a questionnaire item in the dietary survey section asking participants about their weekly breakfast consumption routines over the past year. Participants were categorized into two groups, namely “0–2 breakfasts per week” and “3–7 breakfasts per week”; hs-CRP concentrations were measured through blood tests. Results: Comparing between the “infrequent breakfast consumption (0–2 breakfasts per week)” and “frequent breakfast consumption (3–7 breakfasts per week)” groups, the mean hs-CRP was found to be significantly higher in the “infrequent breakfast consumption” group, even after adjusting for age, body mass index, physical activity, alcohol consumption, systolic blood pressure, blood pressure medication, fasting blood glucose, and triglycerides (mean hs-CRP: frequent breakfast consumption, 1.36±0.09 mg/L; infrequent breakfast consumption, 1.17±0.05 mg/L; P-value=0.036). Conclusion Less frequent breakfast consumption was associated with elevated hs-CRP levels. Further large-scale studies incorporating adjusted measures of daily eating patterns as well as food quality and quantity are required for a deeper understanding of the role of breakfast in the primary prevention of chronic inflammatory diseases.

Purpose: 46,XX disorders of sex development (DSD) involve atypical genitalia accompanied by a normal female karyotype. This study was performed to investigate the clinical characteristics and long-term outcomes of patients with 46,XX DSD. Methods: The study included 34 patients with 46,XX DSD who presented with ambiguous genitalia or delayed puberty. Patients with congenital adrenal hyperplasia were excluded. Clinical phenotypes and overall outcomes were analyzed retrospectively. Results: Age at presentation ranged from birth to 40 years (median, 0.6 years), and the follow-up period ranged from 0.3 to 29.7 years (median, 8.8 years). Twenty patients were assigned female (58.8%). Etiologies included disorders of gonadal development (n=22), exogenous androgen exposure during pregnancy (n=5), association with syndromic disorders or genital anomalies (n=2), and unclassified causes (n=5). Ovotestis was the most frequent gonadal pathology (41.7%). Müllerian duct remnants were usually underdeveloped (52.9%) or absent (23.5%). Spontaneous puberty occurred in 17 of the 21 patients of pubertal age, while 9 patients required sex hormone replacement therapy. Gonadal complications were observed in 4 patients (gonadal tumors [n=3], and spontaneous gonadal rupture [n=1]), and gender dysphoria occurred in 1 patient who was assigned male. Conclusion This study described the wide phenotypic spectrum and pubertal outcome of patients with 46,XX DSD. Long-term multidisciplinary monitoring for pubertal development, fertility, gender identity, and gonadal complications is recommended.