Background/Aims: Krebs von den Lungen-6 (KL-6) is associated with prognosis in patients with COVID-19. However, there is limited data on the correlation between the prognosis of COVID-19 and varying KL-6 levels at different time points. We investigated the optimal cutoff values of the initial and peak serum KL-6 levels to predict mortality and evaluated their correlation with mortality. Methods: This retrospective cohort study collected data on serially collected serum KL-6 levels in patients hospitalized with COVID-19 between October 2020 and January 2022 at a single tertiary hospital in South Korea. The area under the receiver operating characteristic curve and Youden index were used to determine the cutoff points for the initial and peak KL-6 levels that best predicted 30-day mortality. The association between the initial and peak KL-6 values was assessed by univariate and multivariate logistic regression models. Results: A total of 349 patients were included in this study. The mean initial and peak KL-6 levels were significantly higher in the non-survivor group than in the survivor group. The initial and peak KL-6 values that best predicted 30-day mortality were 491.85 U/mL and 660.05 U/mL, respectively. An initial KL-6 level greater than 491.85 U/mL and a peak KL-6 level greater than 660.05 U/mL were significantly associated with 30-day mortality. Conclusions The initial and peak levels of KL-6 were significantly associated with 30-day mortality in hospitalized patients with COVID-19. These findings suggest that serially monitoring blood KL-6 levels could be a valuable prognostic indicator for COVID-19.

Background: This study evaluated adherence to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) and Korean guidelines in the prescription patterns of respiratory specialists for stable chronic obstructive pulmonary disease (COPD) management. Methods: Data were collected on medications from 2011 to 2022 using the Korea COPD Subtype Study (KOCOSS) cohort. Patients were divided into two groups: those registered before and after 2019, and we analyzed the percentage of patients meeting the recommended treatment criteria established by each guideline. Results: Among 3,477 patients, 85.6% received pharmacological therapy, and 81.6% utilized inhaled medications. Compared to patients enrolled before 2019, there was an increase in inhaler prescriptions among those registered after 2019 (79.7% vs. 86.7%), with dual bronchodilators being the predominant therapy prescribed. Of the patients receiving treatment, 56.9% adhered to the Korean 2018 guideline. Compliance with the GOLD 2019 and GOLD 2023 guidelines was observed in 31.3% and 28.0% of cases, respectively. When analyzing inhaler prescription patterns according to both subgroups and considering the Korean 2018, GOLD 2019, and GOLD 2023 guidelines concurrently, the adherence rates were as follows: (56.6%, 37.8%, 24.0%) and (57.7%, 14.0%, 38.6%). Conclusion Adherence rates were higher for the Korean guideline compared to the GOLD recommendations. Furthermore, alignment with both the Korean 2018 and GOLD 2023 guidelines increased among patients enrolled after 2019, compared to those registered earlier. These findings suggest that physicians are modifying their therapeutic strategies to align with both domestic and recent international guidelines.

Rhino-orbito-cerebral mucormycosis (ROCM) is a rare fungal infection that may be fatal in immunocompromised patients. Acupuncture is commonly used in Eastern Asia in addition to steroid medication for the treatment of Bell’s palsy. For such patients with comorbid medical conditions, potential risks might arise after the acupuncture procedure; however, ROCM following acupuncture therapy has not been reported to date. Here we present a rare case of invasive mucormycosis that began from the facial skin after acupuncture procedure. In this case, the patient was suspected of ROCM infection and emergently treated with surgical debridement and antifungal therapy. Despite early surgical debridement and medical treatment, the patient died due to brain infarction and invasion of mucormycosis into the internal carotid artery and cavernous sinus. Although acupuncture therapy is considered relatively safe in general, care should be taken when performing acupuncture in patients with underlying diseases that cause immunosuppression.

This paper details the development and implementation of Yonsei Medical E-Learning System 3.0 (YES 3.0), a new learning management system (LMS) for Yonsei University College of Medicine. Driven by the need to adapt to a rapidly changing medical education landscape, YES 3.0 addresses the previous system’s limitations and incorporates advanced features designed to improve learning experiences and educational outcomes. The development process involved extensive collaboration among faculty, students, staff, and the system developer, ensuring the system's alignment with the unique needs of the medical education environment. YES 3.0 features real-time monitoring of learning progress, comprehensive evaluation and grade management, personalized learning path recommendations, effective learner history management, and interview/guidance management functionalities. The system also supports the newly revised CDP2023 (Curriculum Development Project 2023) curriculum, with integrated learning across all courses and a strengthened scholarly advanced course. By automating and streamlining various educational processes, YES 3.0 enables maximized learning efficiency, promotes learner-centered education, and supports the cultivation of future medical professionals equipped to navigate the evolving healthcare environment. Implementing the system is expected to have positive impacts on both educational and economic aspects, contributing to the advancement of medical education at Yonsei University College of Medicine. This study also aims to offer insights and expected outcomes that can serve as a reference for other medical schools in adopting and operating LMS, ultimately providing useful information to educators considering establishing a digital learning environment.

Purpose: Lupus nephritis (LN) can be caused by the complement activation. This study aimed to investigate the differences and clinical implications of the activation pattern of the complement system for pediatric and adult LN patients. Methods: We retrospectively reviewed the medical records of 40 patients (14 pediatric and 26 adult patients) diagnosed with LN through kidney biopsy. Results: The mean ages at diagnosis of pediatric and adult patients were 11.7±2.92 and 37.3±13.5 years, respectively. At the first LN diagnosis, compared with adult patients, pediatric patients had a higher estimated glomerular filtration rate and milder proteinuria; however, there was no statistical significance. The age-adjusted mean serum complement 3 value was significantly lower in the pediatric group (33.0±11.3 mg/dL) than in the adult group (50.8±25.2 mg/dL) (P<0.01). Based on the findings of kidney biopsy, no significant differences were observed in the severity of pathologic classification and the positive rate of complements between adults and children. However, the chronicity index score of adult patients was significantly higher than that of pediatric patients and in the case of complement 4d, despite a similar positive rate, the intensity was significantly stronger for adults (2.35±0.83 vs. 1.54±0.52, (P=0.04). Conclusions The activation pattern of the complement system in LN differs clinicopathologically between pediatric and adult patients and these differences might play an important role in the age-dependent prognosis of LN.

Background: Recombinant human follicle-stimulating hormone (rhFSH) is commonly used to treat female infertility, but its short half-life necessitates multiple doses. Even corifollitropin alfa, with an extended half-life, requires supplementary injections of rhFSH after 7 days. This study aimed to develop and evaluate a long-acting follicle-stimulating hormone (FSH) formulation using anti-serum albumin Fab-associated (SAFA) technology to avoid additional injections and enhance ovarian function. Methods: SAFA-FSH was synthesized using a Chinese hamster ovary expression system. Its biological efficacy was confirmed through assays measuring its ability to stimulate cyclic adenosine monophosphate (cAMP) production, estradiol synthesis, and the expression of human cytochrome P450 family 19 subfamily A member 1 (hCYP19α1) and human steroidogenic acute regulatory protein (hSTAR) in human ovarian granulosa (KGN) cells. To evaluate the effects of SAFA-FSH, we compared its impact on serum estradiol levels and ovarian weight increase with that of rhFSH in Sprague-Dawley (SD) rats using the modified Steelman-Pohley test. Results: The results indicated that SAFA-FSH induces cAMP synthesis in KGN cells and upregulates the expression of hCYP19α1 and hSTAR in a dose-dependent manner. Female SD rats, aged 21 days, receiving daily subcutaneous human chorionic gonadotropin injections for 5 days exhibited a significant increase in serum estradiol levels and ovarian weight when administered SAFA-FSH on the first day or when given nine injections of rhFSH over 5 days. Notably, the group receiving SAFA-FSH on the first and third days demonstrated an even greater rise in serum estradiol levels and ovarian weight. Conclusion These findings suggest that SAFA-FSH presents a promising alternative to current rhFSH treatments for female infertility. However, further research is essential to thoroughly assess its safety and efficacy in clinical contexts.

This study compares biomarker levels among environmentally vulnerable residents in Korea, the general Korean population, and Asians in the United States. We selected 953 exposed residents and 204 controls from the Forensic Research via Omics Markers in Environmental Health Vulnerable Areas (FROM) study (2021-2023), 4,239 participants from the fourth Korean National Environmental Health Survey (2018-2020), and 996 Asians from the U.S. National Health and Nutrition Examination Survey (2017-March 2020). The analyzed biomarkers included blood and urinary metals, urinary metabolites of polycyclic aromatic hydrocarbons, nicotine, volatile organic compounds, and serum perfluorocarbon metabolites. The highest median biomarker levels varied by pollution source among older adults. In refineries, blood lead and cadmium (Cd), as well as urinary Cd and 2-hydroxyfluorene, were highest. Abandoned metal mines exhibited the highest blood and urinary mercury, urinary Cd, total arsenic (As), 2-naphthol, and cotinine levels. Coal-fired power plants showed the highest urinary 1- hydroxyphenanthrene levels, while cement factories had the highest urinary As3+ levels. Sprawls demonstrated the highest urinary monomethylarsonic acid, 1-hydroxypyrene, and phenylglyoxylic acid levels, and industrial areas recorded the highest levels of trans, trans-muconic acid, benzylmercapturic acid, and 2-methylhippuric acid. In general, biomarker levels were higher among exposed residents in the FROM study than in the general population; however, urinary 2-hydroxyfluorene and As5+ levels did not differ significantly. Exposure to pollution sources in environmentally vulnerable areas may elevate biomarker levels in residents.

Alzheimer disease (AD) diagnosis is confirmed using a medley of modalities, such as the detection of amyloid-β (Aβ) neuritic plaques and neurofibrillary tangles with positron electron tomography (PET) or the appraisal of irregularities in cognitive function with examinations. Although these methods have been efficient in confirming AD pathology, the rising demand for earlier intervention during pathogenesis has led researchers to explore the diagnostic potential of fluid biomarkers in cerebrospinal fluid (CSF) and plasma. Since CSF sample collection is invasive and limited in quantity, biomarker detection in plasma has become more attractive and modern advancements in technology has permitted more efficient and accurate analysis of plasma biomolecules. In this study, we found that a composite of standard factors, Aβ40 and total tau levels in plasma, divided by the variation factor, plasma Aβ42 level, provide better correlation with amyloid neuroimaging and neuropsychological test results than a level comparison between total tau and Aβ42 in plasma. We collected EDTA-treated blood plasma samples of 53 subjects, of randomly selected 27 AD patients and 26 normal cognition (NC) individuals, who received amyloid-PET scans for plaque quantification, and measured plasma levels of Aβ40, Aβ42, and total tau with digital enzyme-linked immunosorbent assay (ELISA) in a blinded manner. There was difficulty distinguishing AD patients from controls when analyzing biomarkers independently. However, significant differentiation was observed between the two groups when comparing individual ratios of total-tau×Aβ40/Aβ42. Our results indicate that collectively comparing fluctuations of these fluid biomarkers could aid in monitoring AD pathogenesis.

Rhino-orbito-cerebral mucormycosis (ROCM) is a rare fungal infection that may be fatal in immunocompromised patients. Acupuncture is commonly used in Eastern Asia in addition to steroid medication for the treatment of Bell’s palsy. For such patients with comorbid medical conditions, potential risks might arise after the acupuncture procedure; however, ROCM following acupuncture therapy has not been reported to date. Here we present a rare case of invasive mucormycosis that began from the facial skin after acupuncture procedure. In this case, the patient was suspected of ROCM infection and emergently treated with surgical debridement and antifungal therapy. Despite early surgical debridement and medical treatment, the patient died due to brain infarction and invasion of mucormycosis into the internal carotid artery and cavernous sinus. Although acupuncture therapy is considered relatively safe in general, care should be taken when performing acupuncture in patients with underlying diseases that cause immunosuppression.