1.Longitudinal analysis of serotypes, virulence factors, and MLST profiles of Pasteurella multocida from porcine pneumonia in South Korea (2016–2023)
Sung-Hyun MOON ; Da-Yun BAE ; Taeyeon KIM ; Won-Il KIM ; Yeonsu OH ; Ho-Seong CHO
Journal of Veterinary Science 2026;27(1):e9-
Objective:
This study performed a longitudinal molecular characterization of P. multocidaisolates from pigs with respiratory lesions in South Korea (2016–2023), including subspecies identification, capsular serogrouping, virulence gene profiling, and multilocus sequence typing (MLST).
Methods:
A total of 1,358 pneumonic lung samples were collected from 960 pig farms between 2016 and 2023, yielding 169 P. multocida isolates. Subspecies were assigned by 16S rRNA gene sequencing. Capsular serogroups were determined using multiplex Virulence genes (pfhA, hgbB, tbpA, and toxA) were detected by PCR assays. MLST was conducted using the RIRDC scheme, and phylogenetic analysis of concatenated loci assessed clonal relationships.
Results:
Serogroup A predominated (109/169, 64.5%), followed by D (47/169, 27.8%) and B (3/169, 1.8%). Serogroups F and A/D were each detected once (0.6%), and 8 isolates were untypable (4.7%). Co-detection of hgbB and pfhA occurred in multiple isolates. Notably, two serogroup B isolates carried both genes, representing the first such finding in Korea and suggesting enhanced virulence potential. MLST identified 5 clonal complexes and 15 sequence types, including ST9 linked to serogroup B.
Conclusions
and Relevance: The emergence of serogroup B/ST9 isolates co-harboring hgbB and pfhA highlights evolving virulence patterns in Korean swine and supports continued molecular and genomic surveillance to guide control strategies and reduce health risks.
2.Actinobacillus pleuropneumoniaein Korea (2015-2025): serovar distribution, toxin gene profiles, antimicrobial resistance, and identification of an apxIICA-deficient serovar 15 profile
Da-Yun BAE ; Eun Ju KANG ; Yun-Chae CHO ; Yujoon LIM ; Sung-Hyun MOON ; Won-Il KIM ; Yeonsu OH ; Ho-Seong CHO
Journal of Veterinary Science 2026;27(3):e39-
Objective:
To provide a decade-long molecular and phenotypic characterization of APP isolates from Korean pig farms, focusing on the serovar distribution, apx-based toxingene profiles, and antimicrobial susceptibility.
Methods:
Between 2015 and 2025, 1,215 pneumonic lung samples from 965 pig farms yielded 132 APP isolates. The species identity was confirmed by 16S rRNA sequencing. The serovars were determined using capsule polysaccharide (CPS) gene-based multiplex polymerase chain reaction (PCR). Toxin genes (apxIA–apxIVA) were profiled, and the antimicrobial susceptibility to 29 agents was assessed by broth microdilution according to the Clinical and Laboratory Standards Institute guidelines.
Results:
Serovar 1 was predominant (66.7%), followed by serovars 5 (17.4%) and 2 (6.8%).CPS multiplex PCR identified three isolates (2.3%) as serovar 15, which displayed heterogeneous toxin gene profiles, including apxIICA-deficient profiles. Most isolates exhibited classical repeats-in-toxin operon arrangements, suggesting ongoing diversification of toxin gene profiles. High resistance rates were observed for oxytetracycline (90.9%) and florfenicol (50.8%), and recurrent multidrug-resistant combinations were frequently detected.
Conclusions
and Relevance: Serovar 1 is dominant in Korea, but the emergence of atypical toxin gene profiles in serovar 15 may carry immunological implications. Persistent resistance to older drug classes underscores the necessity for long-term molecular surveillance, evaluation of vaccine coverage against evolving strains, and enhanced antimicrobial stewardship to strengthen the control efforts for porcine pleuropneumonia in Korea.
3.The Prevalence of BRAF Mutation in Papillary Thyroid Carcinoma Decreases Significantly with Increasing Tumor Size
Da Eun LEEM ; Hyunju PARK ; Ji Hyun YOO ; Bo Ram KIM ; Young Lyun OH ; Tae Hyuk KIM ; Sun Wook KIM ; Jae Hoon CHUNG
International Journal of Thyroidology 2026;19(1):95-103
Background and Objectives:
Studies investigating the correlation between papillary thyroid carcinoma (PTC) tumor size and the prevalence of the B-type Raf kinase (BRAF) mutation have yielded conflicting results. Therefore, we evaluated the prevalence of BRAF mutation according to tumor size in a large cohort of PTC patients to clarify this association.
Materials and Methods:
We retrospectively analyzed 6,438 patients with surgically diagnosed classic PTC between January 2009 and December 2017 at Samsung Medical Center, Seoul, Republic of Korea.During the study period, BRAF mutation testing was attempted on all fine-needle aspiration specimens, except for a small number of inadequate specimens. All other histologic subtypes were excluded. The prevalence of BRAF mutation was assessed based on tumor size, and further analyzed by age group and sex according to tumor size.
Results:
The overall prevalence of BRAF mutation was 79.2%. When PTCs ≤1 cm were excluded, the prevalence was 77.2%. The prevalence significantly decreased with increasing tumor size (p for trend <0.001). It was significantly higher in men than in women (p=0.013), but did not differ by age. The inverse correlation between tumor size and prevalence was prominent in patients aged 20-49 years but was less distinct in those aged 50 years and older.
Conclusion
In this large cohort of patients with PTC, the prevalence of BRAF mutation significantly decreased with increasing tumor size. These findings suggest that BRAF mutation is enriched in smaller surgically treated classic PTCs and may provide a hypothesis-generating clue regarding its role in early PTC development, although selection bias cannot be excluded.
4.Resting-State Electroencephalography as a Neurophysiological Marker Complementing Clinician-Rated Dementia Severity
Hyeonjin KIM ; Da Young OH ; Hahyun LEE ; Su Mi PARK ; Jun-Young LEE
Journal of Korean Geriatric Psychiatry 2026;30(1):28-34
Objective:
Reliable staging of dementia is critical for both clinical practice and research. Although the Clinical Dementia Rating (CDR) is widely used to assess dementia severity, it is subject to subjectivity and inter-rater variability. Resting-state electroencephalography (EEG) may provide objective neurophysiological information associated with clinical severity.
Methods:
Resting-state EEG data from 600 adults aged ≥60 years in Korea were analyzed. Relative power spectral density was extracted from 19 electrodes across six frequency bands. Ordinal logistic regression and linear regression analyses exam-ined associations between resting-state EEG spectral features and CDR Global and CDR Sum of Boxes (CDR-SB) scores. All models adjusted for age, sex, education, and depressive symptoms, with false-discovery-rate correction.
Results:
Ordinal logistic regression demonstrated that higher resting-state theta-band EEG power was significantly associatedwith greater CDR Global severity, particularly in frontal, temporal, central, and parietal regions. Consistently, linear regressionanalyses revealed that higher CDR-SB scores were associated with increased theta in widespread cortical areas. No significantassociations were observed in other frequency bands.
Conclusion
EEG spectral slowing—marked by elevated theta power—was consistently related to CDR-defined dementia se-verity. Resting-state EEG can potentially serve as an objective neurophysiological correlate that informs clinician-rated staging and enhances the reliability of dementia severity assessment.
5.Occupational stress (KOSS®19): scale development and validation in the Korean context
Hansoo SONG ; Hyoung Ryoul KIM ; Inah KIM ; Jin-Ha YOON ; Sang-Baek KOH ; Sung-Soo OH ; Hee-Tae KANG ; Da-Yee JEUNG ; Dae-Sung HYUN ; Chunhui SUH ; Sei-Jin CHANG
Annals of Occupational and Environmental Medicine 2025;37(1):e12-
Background:
The Korean Occupational Stress Scale (KOSS) was developed in 2004. During this time, industrial structures have evolved, and societal awareness of occupational stress has changed. This study aims to develop and validate a revised version of the Korean Occupational Stress Scale (KOSS®19), tailored for workers, reflecting these changes.
Methods:
The KOSS®19 was developed based on the 26-item KOSS–short form (SF) through a review by eight experts. A survey was conducted including 359 service industry workers, comprising the KOSS®19, Burnout, and Depression scales. The KOSS®19 subscales were restructured, and their reliability and validity were evaluated.
Results:
The KOSS®19 composed of eight subscales: hazardous physical environment (2 items), high job demand (3 items), insufficient job control (2 items), low social support (2 items), job insecurity (2 items), organizational injustice (4 items), lack of reward (2 items), and work-life imbalance (2 items). The reliability and validity of the KOSS®19 were found to be satisfactory.
Conclusions
The KOSS®19 is a suitable tool for assessing occupational stress, effectively replacing the original KOSS and KOSS-SF.
6.Emotional labor (KELS®11): scale development and validation in the Korean context
Da-Yee JEUNG ; Hyoung Ryoul KIM ; Hansoo SONG ; Inah KIM ; Jin-Ha YOON ; Sang-Baek KOH ; Sung-Soo OH ; Hee-Tae KANG ; Dae-Sung HYUN ; Chunhui SUH ; Sei Jin CHANG
Annals of Occupational and Environmental Medicine 2025;37(1):e13-
Background:
Emotional labor refers to the management of emotions and expressions to meet the emotional requirements of a job role. This study aimed to develop a revised version of the Korean Emotional Labor Scale (KELS®11), based on the first edition (KELS-24) introduced in 2014, and to provide practical applications and guidelines for its use in the Korean workplace through a validation process.
Methods:
The revised version of KELS®11 was derived from the 24-item KELS, following a review process involving eight experts. To validate the scale’s reliability and validity, a self-administered survey was conducted among 359 service industry workers using KELS®11, burnout, and depression scales. KELS®11 was reclassified, and its reliability and validity were evaluated. Receiver operating characteristic curve analysis was conducted to establish sex-specific cutoff values (normal vs. high-risk groups).
Results:
KELS®11 was designed to account for individual, organizational, and cultural contexts. It consists of four subscales and 11 items: “emotional regulation” (2 items), “emotional dissonance” (3 items), “organizational monitoring” (2 items), and “organizational protective system for emotional labor” (4 items). KELS®11 demonstrated good validity (content validity ratio: 0.84; item convergence/discriminant validity success rates: 100%; correlation with burnout: r = 0.185–0.436, p < 0.01; correlation with depression: r = 0.128–0.339, p < 0.05) and reliability (Cronbach’s alpha: 0.597–0.795). Additionally, sex-specific reference values were established to determine risk groups based on the intensity of emotional labor exposure.
Conclusions
KELS®11 is a validated and reliable measurement tool designed to assess the intensity and magnitude of emotional labor in the workplace. The revised tool reflects critical considerations in the development of emotional labor measurement scales.
7.Workplace Violence (KWVS®13): scale development and validation in the Korean context
Da-Yee JEUNG ; Hyoung Ryoul KIM ; Hansoo SONG ; Inah KIM ; Jin-Ha YOON ; Sang-Baek KOH ; Sung-Soo OH ; Hee-Tae KANG ; Dae-Sung HYUN ; Chunhui SUH ; Sei-Jin CHANG
Annals of Occupational and Environmental Medicine 2025;37(1):e14-
Background:
Workplace violence refers to any act or threat of physical violence, verbal abuse, harassment, intimidation, bullying, mobbing, or other aggressive and disruptive behaviors that occur at work. This study aims to develop and validate a revision of the Korean Workplace Violence Scale (KWVS®13), based on the first edition of the Korean Workplace Violence Scale (KWVS-24), and to provide practical applications and guidelines for the Korean workplace environment.
Methods:
The revised KWVS®13 was developed by restructuring the 24-item KWVS through a review process involving eight experts. To validate the reliability and validity of KWVS®13, a self-administered survey comprising KWVS®13, burnout, and depression scales was conducted among 359 service industry workers. KWVS®13 was reclassified, and its reliability and validity were assessed. Receiver operating characteristic curve analysis was performed to establish sex-specific cutoff values (normal vs. risk) of the scale.
Results:
KWVS®13 consists of 13 items across four subscales: “psychological and sexual violence from customers” (4 items), “psychological and sexual violence from supervisors or coworkers” (4 items), “physical assault from customers, supervisors, or coworkers” (2 items), and “organizational protective system for workplace violence” (3 items). We found that KWVS®13 shows relatively good validity (content validity ratio for content validity: 0.888; success rate of item convergent and discriminant validity: 100%, and significant correlation coefficient with burnout (r = 0.115–0.83, p < 0.05) and depression (r = 0.098–0.348, p < 0.05) with the exception of Organizational Violence Protection System for Workplace Violence) and reliability (Cronbach’s alpha: 0.827–0.860). The reference values for determining risk groups according to the intensity of exposure to workplace violence are presented separately by sex.
Conclusions
KWVS®13 is a robust and useful measurement tool to objectively and quantitatively assess the intensity and magnitude of workplace violence. It incorporates important considerations for workplace violence assessment and provides a reliable framework for evaluating workplace violence in various professional settings.
8.Immune Checkpoint Inhibitor Score Predicts Survival Benefit of Immunotherapy in Patients with Non-small Cell Lung Cancer
Da Hyun KANG ; Chang-Min CHOI ; Cheol-Kyu PARK ; In-Jae OH ; Young-Chul KIM ; Seong Hoon YOON ; Yoonjoo KIM ; Jeong Eun LEE
Tuberculosis and Respiratory Diseases 2024;87(4):483-493
Background:
The use of immune checkpoint inhibitors (ICIs) in patients with advanced lung cancer is increasing. Despite ongoing studies to predict the efficacy of ICIs, its use in clinical practice remains difficult. Thus, we aimed to discover a predictive marker by analyzing blood cell characteristics and developing a scoring system for patients treated with ICIs.
Methods:
This was a prospective multicenter study in patients with advanced nonsmall cell lung cancer (NSCLC) who received ICIs as second-line treatment from June 2021 to November 2022. Blood cell parameters in routine blood samples were evaluated using an automated hematology analyzer. Immune checkpoint inhibitor score (IChIS) was calculated as the sum of neutrophil count score and immature granulocyte score.
Results:
A total of 143 patients from four institutions were included. The treatment response was as follows: partial response, 8.4%; stable disease, 37.1%; and progressive disease, 44.8%. Median progression-free survival and overall survival after ICI treatment was 3.0 and 8.3 months, respectively. Median progression-free survival in patients with an IChIS of 0 was 4.0 months, which was significantly longer than 1.9 months in patients with an IChIS of 1 and 1.0 month in those with an IChIS of 2 (p=0.001). The median overall survival in patients with an IChIS of 0 was 10.2 months, which was significantly longer than 6.8 and 1.8 months in patients with an IChIS of 1 and 2, respectively (p<0.001).
Conclusion
Baseline IChIS could be a potential biomarker for predicting survival benefit of immunotherapy in NSCLC.
9.Long-Term Follow-Up of Interstitial Lung Abnormalities in Low-Dose Chest CT in Health Screening: Exploring the Predictors of Clinically Significant Interstitial Lung Diseases Using Artificial Intelligence-Based Quantitative CT Analysis
Won Jong JEONG ; Bo Da NAM ; Jung Hwa HWANG ; Chang Hyun LEE ; Hee-Young YOON ; Eun Ji LEE ; Eunsun OH ; Jewon JEONG ; Sung Hwan BAE
Journal of the Korean Society of Radiology 2024;85(6):1141-1156
Purpose:
This study examined longitudinal changes in interstitial lung abnormalities (ILAs) and predictors of clinically significant interstitial lung diseases (ILDs) in a screening population with ILAs.
Materials and Methods:
We retrieved 36891 low-dose chest CT records from screenings between January 2003 and May 2021. After identifying 101 patients with ILAs, the clinical findings, spirometry results, and initial and follow-up CT findings, including visual and artificial intelligence-based quantitative analyses, were compared between patients diagnosed with ILD (n = 23, 23%) and those who were not (n = 78, 77%). Logistic regression analysis was used to identify significant parameters for the clinical diagnosis of ILD.
Results:
Twenty-three patients (n = 23, 23%) were subsequently diagnosed with clinically significant ILDs at follow-up (mean, 8.7 years). Subpleural fibrotic ILAs on initial CT and signs of progression on follow-up CT were common in the ILD group (both p < 0.05). Logistic regression analysis revealed that emerging respiratory symptoms (odds ratio [OR], 5.56; 95% confidence interval [CI], 1.28–24.21; p = 0.022) and progression of ILAs at follow-up chest CT (OR, 4.07; 95% CI, 1.00–16.54; p = 0.050) were significant parameters for clinical diagnosis of ILD.
Conclusion
Clinically significant ILD was subsequently diagnosed in approximately one-quarter of the screened population with ILAs. Emerging respiratory symptoms and progression of ILAs at followup chest CT can be predictors of clinically significant ILDs.
10.Long-Term Follow-Up of Interstitial Lung Abnormalities in Low-Dose Chest CT in Health Screening: Exploring the Predictors of Clinically Significant Interstitial Lung Diseases Using Artificial Intelligence-Based Quantitative CT Analysis
Won Jong JEONG ; Bo Da NAM ; Jung Hwa HWANG ; Chang Hyun LEE ; Hee-Young YOON ; Eun Ji LEE ; Eunsun OH ; Jewon JEONG ; Sung Hwan BAE
Journal of the Korean Society of Radiology 2024;85(6):1141-1156
Purpose:
This study examined longitudinal changes in interstitial lung abnormalities (ILAs) and predictors of clinically significant interstitial lung diseases (ILDs) in a screening population with ILAs.
Materials and Methods:
We retrieved 36891 low-dose chest CT records from screenings between January 2003 and May 2021. After identifying 101 patients with ILAs, the clinical findings, spirometry results, and initial and follow-up CT findings, including visual and artificial intelligence-based quantitative analyses, were compared between patients diagnosed with ILD (n = 23, 23%) and those who were not (n = 78, 77%). Logistic regression analysis was used to identify significant parameters for the clinical diagnosis of ILD.
Results:
Twenty-three patients (n = 23, 23%) were subsequently diagnosed with clinically significant ILDs at follow-up (mean, 8.7 years). Subpleural fibrotic ILAs on initial CT and signs of progression on follow-up CT were common in the ILD group (both p < 0.05). Logistic regression analysis revealed that emerging respiratory symptoms (odds ratio [OR], 5.56; 95% confidence interval [CI], 1.28–24.21; p = 0.022) and progression of ILAs at follow-up chest CT (OR, 4.07; 95% CI, 1.00–16.54; p = 0.050) were significant parameters for clinical diagnosis of ILD.
Conclusion
Clinically significant ILD was subsequently diagnosed in approximately one-quarter of the screened population with ILAs. Emerging respiratory symptoms and progression of ILAs at followup chest CT can be predictors of clinically significant ILDs.

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