1.Optimization of Natural Killer Cell Expansion with K562-mbIL-18/-21 Feeder Cells and Assurance of Feeder Cell-Free Products
Hantae JO ; Yujung JO ; Seung Kwon KOH ; Mijeong LEE ; Jinho KIM ; SoonHo KWEON ; Jeehun PARK ; Hyun‑Young KIM ; Duck CHO
Annals of Laboratory Medicine 2026;46(2):180-189
Background:
Cancer cell line-derived feeder cells enhance natural killer (NK) cell expansion; however, concerns regarding viable residual feeder cells in the final product limit their use. Evidence supporting the safety of NK-sensitive K562-based feeders, even when irradiated, is scarce. We optimized an NK cell expansion protocol using genetically engineered K562-mbIL-18/-21 (GE-K562) feeder cells and clinical-grade media and confirmed the absence of residual feeder cells.
Methods:
NK cell expansion efficiency was compared between feeder-free and feederbased systems using CTS NK-Xpander Medium. To achieve optimal NK expansion, various peripheral blood mononuclear cell (PBMC)-to-feeder ratios and re-stimulation frequencies were tested over 21 days. Flow cytometry and BCR::ABL1 quantitative reverse transcription PCR (RT-qPCR) were used to confirm the absence of feeder cells in the final NK cell product.
Results:
Feeder-based systems showed superior NK cell fold expansion compared with that of feeder-free systems. Among feeder-based conditions, NK cells expanded 5,224-fold at a 2:1 PBMC-to-feeder ratio after 3 weeks, relative to 1,450-fold at a 6:1 ratio (P < 0.05).Re-stimulation on days 7 and 14 further increased expansion up to 261,457-fold. Irradiated feeder cells showed no proliferation and were eliminated within 3–6 days. On day 21, flow cytometry and BCR::ABL1 RT-qPCR results confirmed the absence of residual feeder cells.
Conclusions
Our optimized NK cell expansion protocol using irradiated GE-K562 feeder cells and clinical-grade media offers a safe and scalable approach to generating large numbers of NK cells, supporting its potential use in clinical immunotherapy applications.
2.Understanding Adolescent Non-Suicidal Self-Injury:A Narrative Review of Theoretical Models and Evidence-Based Psychotherapies
Journal of the Korean Academy of Child and Adolescent Psychiatry 2026;37(1):33-43
Objectives:
Adolescent non-suicidal self-injury (NSSI) is a marker of severe emotional distress and a significant public health concern.This narrative review aimed to synthesize major theoretical models explaining the psychopathology of NSSI and critically evaluate the efficacy of evidence-based psychotherapies using the most recent high-level evidence.
Methods:
We searched articles in major academic databases published from January 2000 up to June 2025. We prioritized studies on adolescents, including efficacy studies (randomized controlled trials and meta-analyses) addressing NSSI as a primary outcome, and key theoretical papers.
Results:
NSSI was understood through integrated models, prominently featuring emotion dysregulation (biosocial theory), experiential avoidance (cognitive-behavioral models), impaired mentalization (attachment theory), and operant conditioning (functional model). The synthesis of high-level evidence, including a 2021 review from Cochrane, indicated that dialectical behavior therapy (DBT) had the strongest empirical support (high-certainty evidence) for reducing adolescent NSSI. However, while mentalization-based treatment, acceptance and commitment therapy, and attachment-based family therapy offered promising mechanism-specific approaches, evidence for their effectiveness for NSSI was preliminary or uncertain.
Conclusion
DBT is currently the first-line treatment for NSSIs in adolescents. However, the field must move toward personalized care.Future research should focus on validating alternative therapies through head-to-head randomized controlled trials, identifying the core change mechanisms across treatments, and implementing stepwise care models to improve accessibility.
3.Technical Note on Cemented Femoral Fixation in Hip Arthroplasty in Elderly Patients: A Preferred Alternative to Uncemented Fixation
Hip & Pelvis 2026;38(2):207-212
Cemented and uncemented fixation are the two categories of fixation in hip arthroplasty (HA). While uncemented stems rely on biologic fixation, cemented HA uses PMMA (polymethylmethacrylate) to lend stability through an interlocking fit between the stem and the cancellous bone. The optimal choice of fixation in elderly patients is debatable. Although patients with poor bone quality have demonstrated good results with uncemented stems, recent improvements in cementing techniques have led to superior outcomes compared to those of older versions. We prefer fully cemented HA in elderly patients to achieve immediate stability that leads to early mobilization and minimal complications, such as intraoperative or postoperative periprosthetic femur fractures. This technical note describes cement fixation in HA.
4.Ethnic Heterogeneity in Reproductive Risk Factors for Breast Cancer, With a Focus on Asian Populations:A Meta-analysis
Youjin HONG ; Soseul SUNG ; Woojin LIM ; Sungji MOON ; Kwang-Pil KO ; Jung Eun LEE ; Inah KIM ; Sun Ha JEE ; Sun-Seog KWEON ; Min-Ho SHIN ; Sangmin PARK ; Seung-Ho RYU ; Sun Young YANG ; Jeongseon KIM ; Sang-Wook YI ; Sue K. PARK
Journal of Cancer Prevention 2026;31(1):20-27
suggest that some reproductive factors associated with BC differ across ethnicities and time trends, perhaps due to the prevalence of reproductive factors and the baseline hazard of BC.
5.Mediating Effect of Empowerment in the Relationship between Nursing Professionalism and Job Satisfaction among Insurance Review Nurses
Eun Jung PARK ; Young-Ran KWEON
Journal of Korean Academy of Nursing Administration 2026;32(1):28-38
This study examined the mediating effect of empowerment on the relationship between nursing professionalism and job satisfaction, with the goal of informing strategies to enhance job satisfaction among insurance review nurses. Methods: A total of 165 insurance review nurses with more than 1 year of work experience in 12 general hospitals (≥500 beds) participated in this study. Data were analyzed using descriptive statistics, t-tests, analysis of variance, Pearson correlation analysis, and multiple regression analysis. The mediating effect was tested using the PROCESS Macro (model 4) in SPSS version 26.0 with 10,000bootstrap samples. Results: The mean scores for nursing professionalism, empowerment, and job satisfaction were 100.37 (standard deviation [SD], 17.03), 86.24 (SD, 17.70), and 45.44 (SD, 9.17), respectively. Significant positive correlations were observed between nursing professionalism and job satisfaction (r=.64, p<.001), empowerment and job satisfaction (r=.77, p<.001), and nursing professionalism and empowerment. Empowerment was found to partially mediate the relationship between nursing professionalism and job satisfaction (95% CI, .20–.44). Conclusion: Enhancing empowerment and strengthening nursing professionalism are essential for improving job satisfaction among insurance review nurses. Institutional interventions that promote professional identity and provide structural empowerment may increase job satisfaction and support retention within this specialized nursing workforce.
6.The Application of L-Serine-Incorporated Gelatin Sponge into the Calvarial Defect of the Ovariectomized Rats
Yoon-Jo LEE ; Ji-Hyeon OH ; Suyeon PARK ; Jongho CHOI ; Min-Ho HONG ; HaeYong KWEON ; Weon-Sik CHAE ; Xiangguo CHE ; Je-Yong CHOI ; Seong-Gon KIM
Tissue Engineering and Regenerative Medicine 2025;22(1):91-104
BACKGROUND:
Osteoporosis, characterized by decreased bone mineral density due to an imbalance between osteoblast and osteoclast activity, poses significant challenges in bone healing, particularly in postmenopausal women. Current treatments, such as bisphosphonates, are effective but associated with adverse effects like medication-related osteonecrosis of the jaw, necessitating safer alternatives.
METHODS:
This study investigated the use of L-serine-incorporated gelatin sponges for bone regeneration in calvarial defects in an ovariectomized rat model of osteoporosis. Thirty rats were divided into three groups: a control group, a group treated with a gelatin sponge containing an amino acid mixture, and a group treated with a gelatin sponge containing L-serine. Bone regeneration was assessed using micro-computed tomography (micro-CT) and histological analyses.
RESULTS:
The L-serine group showed a significant increase in bone volume (BV) and bone area compared to the control and amino acid groups. The bone volume to total volume (BV/TV) ratio was also significantly higher in the L-serine group.Immunohistochemical analysis demonstrated that L-serine treatment suppressed the expression of cathepsin K, a marker of osteoclast activity, while increasing serine racemase activity.
CONCLUSION
These findings suggest that L-serine-incorporated gelatin sponges not only enhance bone formation but also inhibit osteoclast-mediated bone resorption, providing a promising and safer alternative to current therapies for osteoporosis-related bone defects. Further research is needed to explore its clinical applications in human patients.
7.Effectiveness of School-Based Suicide Prevention Programs for Adolescents: A Systematic Review
Young-Ran KWEON ; Young-Mi KWON ; Hyunsoo RYU
Journal of Korean Academy of Psychiatric and Mental Health Nursing 2025;34(1):91-103
Purpose:
This study aimed to systematically evaluate school-based suicide prevention programs for adolescents, focusing on their impact on suicide attempts, knowledge and attitudes about suicide, and help-seeking behaviors.
Methods:
A systematic review was conducted following PRISMA guidelines. Databases searched included PubMed, Cochrane Library, EMBASE, PsycINFO, CINAHL, KMBASE, KoreaMed, and ScienceON. Randomized controlled trials of school-based interventions for middle and high school students were included. The Risk of Bias 2.0 tool was used to assess study quality.
Results:
Out of 1,738 screened records, eight studies met the inclusion criteria. SOS (Signs of Suicide) and SEYLE (Saving and Empowering Young Lives in Europe) programs significantly reduced suicide attempts by 40% and 55%, respectively. Sources of Strength improved help-seeking behavior (ES=0.62, p<.001), though results were inconsistent across interventions. All programs enhanced knowledge and attitudes about suicide, but methodological limitations, such as variability in implementation and reporting, affected reliability.
Conclusion
School-based suicide prevention programs effectively reduce suicide attempts and improve awareness but show mixed results for help-seeking behaviors. Standardized, scalable interventions and rigorous evaluations are needed to enhance their impact.
8.Structural Validity of the Diagnostic Interview for Internet Addiction Scale for Clinical Samples in Korean Children and Adolescents: Exploratory and Confirmatory Factor Analysis
Mi-Sun LEE ; Jung-Seok CHOI ; Yong-Sil KWEON ; Soo-Young BHANG
Psychiatry Investigation 2025;22(2):167-174
Objective:
This study aimed to validate the reliability and validity of the Diagnostic Interview for the Internet Addiction Scale (DIA) among Korean children and adolescents in the clinical setting.
Methods:
We collected the clinical data from university hospitals in South Korea and 194 children and adolescents (aged 7–18 years) completed the questionnaire. The content validity was conducted on 10 items of the DIA and an internal consistency test was performed for the verification of reliability.
Results:
Participants on average, aged 13.17 years (standard deviation=2.46), and 75.3% (n=146) were boys. The DIA was highly correlated with the scores of the Korean scale for Internet addiction for adolescents, Young’s Internet Addiction Test, Internet addiction proneness scale for children and adolescents. The overall sampling suitability of the 10-item scale was tested using the Kaiser–Meyer–Olkin, resulting in a high value of 0.861. The DIA revealed a two-factor structure and the Cronbach’s alpha correlation coefficient for the total scale was 0.806. Confirmatory factor analysis showed an acceptable model fit (root-mean square error of approximation=0.058, comparative fit index=0.950, and Tucker-Lewis Index=0.919).
Conclusion
The DIA may suggest in-depth-scale examinations of the factors that influence Internet addiction. We may expect that DIA would be used efficiently for the diagnosing of Internet addiction and further studies for the assessment.
9.Structural Validity of the Diagnostic Interview for Internet Addiction Scale for Clinical Samples in Korean Children and Adolescents: Exploratory and Confirmatory Factor Analysis
Mi-Sun LEE ; Jung-Seok CHOI ; Yong-Sil KWEON ; Soo-Young BHANG
Psychiatry Investigation 2025;22(2):167-174
Objective:
This study aimed to validate the reliability and validity of the Diagnostic Interview for the Internet Addiction Scale (DIA) among Korean children and adolescents in the clinical setting.
Methods:
We collected the clinical data from university hospitals in South Korea and 194 children and adolescents (aged 7–18 years) completed the questionnaire. The content validity was conducted on 10 items of the DIA and an internal consistency test was performed for the verification of reliability.
Results:
Participants on average, aged 13.17 years (standard deviation=2.46), and 75.3% (n=146) were boys. The DIA was highly correlated with the scores of the Korean scale for Internet addiction for adolescents, Young’s Internet Addiction Test, Internet addiction proneness scale for children and adolescents. The overall sampling suitability of the 10-item scale was tested using the Kaiser–Meyer–Olkin, resulting in a high value of 0.861. The DIA revealed a two-factor structure and the Cronbach’s alpha correlation coefficient for the total scale was 0.806. Confirmatory factor analysis showed an acceptable model fit (root-mean square error of approximation=0.058, comparative fit index=0.950, and Tucker-Lewis Index=0.919).
Conclusion
The DIA may suggest in-depth-scale examinations of the factors that influence Internet addiction. We may expect that DIA would be used efficiently for the diagnosing of Internet addiction and further studies for the assessment.
10.The Application of L-Serine-Incorporated Gelatin Sponge into the Calvarial Defect of the Ovariectomized Rats
Yoon-Jo LEE ; Ji-Hyeon OH ; Suyeon PARK ; Jongho CHOI ; Min-Ho HONG ; HaeYong KWEON ; Weon-Sik CHAE ; Xiangguo CHE ; Je-Yong CHOI ; Seong-Gon KIM
Tissue Engineering and Regenerative Medicine 2025;22(1):91-104
BACKGROUND:
Osteoporosis, characterized by decreased bone mineral density due to an imbalance between osteoblast and osteoclast activity, poses significant challenges in bone healing, particularly in postmenopausal women. Current treatments, such as bisphosphonates, are effective but associated with adverse effects like medication-related osteonecrosis of the jaw, necessitating safer alternatives.
METHODS:
This study investigated the use of L-serine-incorporated gelatin sponges for bone regeneration in calvarial defects in an ovariectomized rat model of osteoporosis. Thirty rats were divided into three groups: a control group, a group treated with a gelatin sponge containing an amino acid mixture, and a group treated with a gelatin sponge containing L-serine. Bone regeneration was assessed using micro-computed tomography (micro-CT) and histological analyses.
RESULTS:
The L-serine group showed a significant increase in bone volume (BV) and bone area compared to the control and amino acid groups. The bone volume to total volume (BV/TV) ratio was also significantly higher in the L-serine group.Immunohistochemical analysis demonstrated that L-serine treatment suppressed the expression of cathepsin K, a marker of osteoclast activity, while increasing serine racemase activity.
CONCLUSION
These findings suggest that L-serine-incorporated gelatin sponges not only enhance bone formation but also inhibit osteoclast-mediated bone resorption, providing a promising and safer alternative to current therapies for osteoporosis-related bone defects. Further research is needed to explore its clinical applications in human patients.

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