1.Stress Accelerates Depressive-Like Behaviors through Increase of Notch2 Expression in N141I Mutation Presenilin-2 Transgenic Mice
Seung Sik YOO ; Sun Mi GU ; Kyung Tak NAM ; Jeong Soon CHOI ; Yong Sun LEE ; In Jun YEO ; Ji Eun YU ; Sanghyeon KIM ; Dong Won LEE ; Hyeon Joo HAM ; Ju Young CHANG ; Jaesuk YUN ; Dong Ju SON ; Sang-Bae HAN ; Jin Tae HONG
Biomolecules & Therapeutics 2026;34(3):544-555
Alzheimer’s disease (AD) is characterized by progressive cognitive deterioration and significant depression. However, the mechanisms linking depression to AD pathology remain unclear. Here, we investigated whether Notch2 signaling mediates depressionlike behaviors in presenilin-2 (PS2) N141I mutant mice, an early-onset AD model. PS2 wild-type (WT) and mutant (MT) mice aged 12-15 months were subjected to unpredictable chronic mild stress (UCMS) for 4 weeks, followed by sucrose preference, tail-hanging, and forced swimming tests. Behavioral assessments showed that UCMS exacerbated anhedonia and immobility only in PS2 MT mice. Molecular analysis revealed concomitant increases in plasma corticosterone, hippocampal γ-secretase activity, and Notch2 expression, and elevated total and phosphorylated glucocorticoid receptor levels in PS2 MT-UCMS mice. Gene expression profiling of human hippocampal datasets confirmed upregulation of NOTCH2 in Alzheimer’s disease and depression.Pharmacological inhibition of γ-secretase and Notch signaling with DAPT normalizes depressive behavior, reduces corticosterone release, attenuates GR phosphorylation, and inhibits Notch2 signaling in PS2 MT mice. These findings identify Notch2 as a pivotal mediator linking chronic stress to molecular changes associated with depression and AD, and suggest that targeting Notch2 signaling may provide therapeutic benefits for comorbid mood and neurodegenerative disorders.
2.Supramalleolar Osteotomy as a Joint-Preserving Procedure for Varus Ankle Osteoarthritis in Elderly Patients: A Report of Two Cases
Ji Yong YUN ; Jin Soo SUH ; Jun Young CHOI
Journal of Korean Foot and Ankle Society 2026;30(1):31-37
Medial opening wedge supramalleolar osteotomy (SMO) is a representative joint-preserving surgical procedure for varus ankle osteoarthritis, based on the principle of load redistribution, with favorable radiologic and clinical outcomes. This procedure is indicated for patients with Takakura stage 2 or 3A arthritis, whereas severe vascular or neurological impairment and osteomyelitis are considered absolute contraindications. Although SMO is generally limited to patients younger than 70 years because of the risk of delayed or nonunion in elderly individuals, few reports on the outcomes in elderly patients have been published. This paper reports two cases of varus ankle osteoarthritis in patients over 75 years of age who underwent SMO after failed conservative treatment, with a follow-up exceeding 2 years, along with a review of the relevant literature. Both cases achieved successful bone union without delayed healing. At the final follow-up, the foot and ankle ability measure (FAAM)–activities of daily living and FAAM-sport scores showed marked improvement compared with the preoperative values. In conclusion, SMO may be a viable joint-preserving treatment option, even in elderly patients, provided that their general health is favorable.
3.Modified Four-Flanged Intrascleral Fixation of Foldable Intraocular Lenses Using a 1-Inch, 30-Gauge Needle for Extraocular Suture Threading
Jun Young HA ; Yong Gu CHO ; Yun Sik YANG
Korean Journal of Ophthalmology 2026;40(1):12-20
Purpose:
To evaluate the efficacy and safety of modified four-flanged intrascleral fixation of foldable intraocular lenses (IOLs) using a 1-inch 30-gauge needle for extraocular suture threading.
Methods:
This retrospective case series included 20 eyes of 20 patients who underwent four-flanged intrascleral IOL fixation using a 1-inch 30-gauge needle, with at least 6 months of follow-up. We modified the original Canabrava technique by inserting a foldable IOL through a 2.4-mm clear corneal incision with a standard injector and performing extraocular suture threading with a 1-inch 30-gauge needle. Collected data included uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), intraocular pressure, spherical equivalent (SE), prediction error (PE), and corneal and lens astigmatism. Postoperative complications and IOL centration were also evaluated.
Results:
Visual acuity improved significantly over the 6-month follow-up; mean preoperative logMAR UCVA was 1.25 ± 0.66 (Snellen equivalent, 20 / 355) and improved to 0.35 ± 0.19 (20 / 45), and logMAR BCVA improved from 0.53 ± 0.38 (20 / 70) to 0.15 ± 0.09 (20 / 30) (p < 0.05). The mean postoperative SE at 6 months was –0.61 ± 1.08 diopters, and PE was –0.25 ± 0.86 diopters. No significant changes in endothelial cell density were observed. Corneal astigmatism remained stable, and lens astigmatism was reduced after surgery, although not significantly. Postoperative complications included one case each of hypotony and vitreous hemorrhage, both resolved with medical therapy. No IOL redislocation, decentration, tilt, or flange-related issues occurred.
Conclusions
Modified four-flanged intrascleral IOL fixation using a 1-inch 30-gauge needle provides stable IOL fixation by pairing a robust suture with the smallest suitable needle. Extraocular suture threading reduces intraocular manipulation, simplifying the procedure and resulting in favorable visual outcomes and low complication rates.
4.Macro-Aspartate Aminotransferase Elevation in a Patient with Chronic Hepatitis B
Nae-Yun HEO ; Jae-Hoon KIM ; Seungha PARK ; Joon Hyuk CHOI ; Tae Oh KIM ; Jin LEE ; Yong Eun PARK ; Kyung Ran JUN
The Korean Journal of Gastroenterology 2026;86(2):122-127
Although aspartate aminotransferase (AST) is a serum marker of hepatocellular damage in chronic hepatitis, it is difficult to interpret very high AST levels with concurrent low alanine aminotransferase (ALT) levels. Macro-AST is an immunoglobulin-AST complex that can present as aberrant high enzymatic activity without significant inflammation in the liver. Two patients with chronic hepatitis B presented with disproportionate AST elevations. Their plasma samples were precipitated with polyethylene glycol (PEG) and stored at 4°C for macro-AST determinations. In Case 1, PEG precipitation showed 100% removal of AST activity, and refrigerated storage resulted in a ~70% decline over seven days, confirming macro-AST. In Case 2, both tests showed minimal changes, suggesting that macro-AST was unlikely. The AST levels normalized after antiviral therapy, suggesting immune-active hepatitis as the probable cause, but the other contributing factors could not be completely excluded. The abrupt decrease in AST activity after PEG precipitation and during refrigeration storage suggests that relatively high AST values compared to ALT might be attributed to the presence of macro-AST.These non-invasive methods for detecting macroenzymes might help the patient avoid unnecessary further work-ups.
5.External Neurolysis for Posterior Interosseous Nerve Syndrome with Refractory Motor Weakness: Clinical Outcomes in a Seven-Patient Case Series
Kihyuk YUN ; Jinseo YANG ; Yong-Jun CHO ; Gwang Yoon CHOI ; Mu Seung PARK
The Nerve 2026;12(1):19-24
Objective:
Posterior interosseous nerve (PIN) syndrome (PINS) is a compressive neuropathy of the deep branch of the radial nerve that primarily presents with motor weakness of finger and thumb extension. Although some patients respond to conservative management, others develop persistent motor deficits requiring surgical decompression. This study aimed to evaluate the clinical outcomes of external neurolysis in patients with PINS presenting with refractory motor weakness.
Methods:
Seven patients with clinically diagnosed PINS who exhibited persistent motor weakness despite conservative treatment and subsequently underwent surgical decompression were retrospectively reviewed. Clinical characteristics, magnetic resonance imaging (MRI) findings, intraoperative compression sites, and postoperative motor recovery were analyzed. Motor strength was evaluated using the Medical Research Council grading system. Preoperative and postoperative motor strength grades were compared using the Wilcoxon signed-rank test.
Results:
The patients presented with progressive weakness of finger extension, resulting in impaired hand opening. MRI demonstrated denervation-related signal changes and atrophy in the affected muscles innervated by the PIN. Surgical exploration revealed compressive structures within the radial tunnel, most commonly at the arcade of Frohse. Significant improvement in motor strength was observed within 2 months postoperatively (thumb extension, p = 0.018; second digit extension, p = 0.011; third to fifth digit extension, p = 0.009). One patient experienced symptom recurrence approximately 6 months after the initial surgery and subsequently underwent revision decompression.
Conclusion
External neurolysis provides meaningful recovery of finger extension in patients with PINS presenting with refractory motor weakness. MRI may support the diagnosis by demonstrating denervation-related morphological changes in the affected muscles. Recurrence of PINS may occur even after initial recovery, highlighting the importance of careful postoperative follow-up.
6.Delayed Retroperitoneal Hematoma Following Intradiscal Electrothermal Therapy: A Case Report of a Rare Complication
Jun-Yong CHA ; Yun-Young PARK ; Jin-Uk KIM ; Jun-Ho LEE ; Seong-Hwan MUN ; Gun AHN ; Il-Tae JANG
The Nerve 2026;12(1):36-40
Intradiscal electrothermal therapy (IDET) is a minimally invasive procedure used to treat discogenic back pain and offers an alternative to surgical intervention in selected patients. Although it is generally considered safe, rare but significant complications can occur and may be difficult to diagnose because their symptoms overlap with those of other spinal conditions. We describe the case of a 69-year-old woman who presented with severe lower back and left buttock pain that was unresponsive to conservative treatment. Magnetic resonance imaging revealed disc bulging with a high-intensity zone at the L4–5 and L5–S1 levels. IDET was performed at the L4–5 level, resulting in initial pain relief. However, the patient returned 7 days later with recurrent pain. Despite undergoing percutaneous epidural neuroplasty at the left L5–S1 level, a medial branch block, and a piriformis muscle block, her symptoms persisted. Further evaluation with spinal computed tomography revealed a retroperitoneal hematoma near the left psoas muscle. Referred pain from the hematoma mimicked discogenic pain, resulting in delayed diagnosis and unnecessary interventions. The patient remained hemodynamically stable and gradually improved with conservative management alone. This case highlights retroperitoneal hematoma as a rare complication of IDET and emphasizes the importance of accurate and timely diagnosis in patients with persistent or worsening symptoms after spinal procedures. Clinicians should consider non-discogenic sources of pain when treatment outcomes deviate from expected patterns.
7.Diagnostic Ability and Correlation of Digital 11C-Methionine PET/CT in Primary Hyperparathyroidism with Inconclusive Standard Imaging
Hee Beom JEONG ; Yong-il KIM ; Soyoon YOON ; Dong Yun LEE ; Beom-Jun KIM ; Seung Hun LEE ; Jin-Sook RYU
Nuclear Medicine and Molecular Imaging 2025;59(1):72-78
Purpose:
11C-Methionine PET/CT is a promising method for detecting parathyroid lesions in patients with primary hyperparathyroidism (PHPT). We aimed to determine the diagnostic ability and correlation of digital 11C-Methionine PET/CT for parathyroid lesions in patients with PHPT, particularly in cases where standard imaging methods yielded inconclusive results.
Methods:
This retrospective analysis was conducted on patients diagnosed with PHPT who underwent digital 11C-Methionine PET/CT imaging because of ambiguous results on standard imaging work-up ( 99m Tc-MIBI parathyroid scan and/or neck ultrasonography). Quantitative 11C-Methionine PET/CT parameters, including maximum standardized uptake value (SUVmax), mean SUV (SUVmean), peak SUV (SUVpeak), parathyroid methionine volume (PMV), and whole methionine uptake(WMU: PMV multiplied by SUVmean) were calculated with various thresholds, and their correlations with biochemical andpathologic parameters were investigated.
Results:
This study included 22 consecutive patients (10 men and 12 women) with a median age of 64.0 years. The lesion detection rate and sensitivity of digital 11C-Methionine PET/CT were 81.8% (18/22) and 100.0% (18/18), respectively.Quantitative analysis revealed that serum PTH (r = 0.490, P = 0.039) and serum calcium (r = 0.583, P = 0.011) were signifi-cantly correlated with PMV50%.
Conclusion
Digital 11C-Methionine PET/CT offers good performance in the detection of parathyroid lesions in PHPT patients with inconclusive standard imaging work-up. The volume parameter of PMV50% significantly correlated biochemi-cal parameters and can serve as a complementary diagnostic tool.
8.Environmental disease monitoring by regional Environmental Health Centers in Korea: a narrative review
Myung-Sook PARK ; Hwan-Cheol KIM ; Woo Jin KIM ; Yun-Chul HONG ; Won-Jun CHOI ; Seock-Yeon HWANG ; Jiho LEE ; Young-Seoub HONG ; Yong-Dae KIM ; Seong-Chul HONG ; Joo Hyun SUNG ; Inchul JEONG ; Kwan LEE ; Won-Ju PARK ; Hyun-Joo BAE ; Seong-Yong YOON ; Cheolmin LEE ; Kyoung Sook JEONG ; Sanghyuk BAE ; Jinhee CHOI ; Ho-Hyun KIM
The Ewha Medical Journal 2025;48(1):e3-
This study explores the development, roles, and key initiatives of the Regional Environmental Health Centers in Korea, detailing their evolution through four distinct phases and their impact on environmental health policy and local governance. It chronicles the establishment and transformation of these centers from their inception in May 2007, through four developmental stages. Originally named Environmental Disease Research Centers, they were subsequently renamed Environmental Health Centers following legislative changes. The analysis includes the expansion in the number of centers, the transfer of responsibilities to local governments, and the launch of significant projects such as the Korean Children’s Environmental Health Study (Ko-CHENS ). During the initial phase (May 2007–February 2009), the 10 centers concentrated on research-driven activities, shifting from a media-centered to a receptor-centered approach. In the second phase, prompted by the enactment of the Environmental Health Act, six additional centers were established, broadening their scope to address national environmental health issues. The third phase introduced Ko-CHENS, a 20-year national cohort project designed to influence environmental health policy by integrating research findings into policy frameworks. The fourth phase marked a decentralization of authority, empowering local governments and redefining the centers' roles to focus on regional environmental health challenges. The Regional Environmental Health Centers have significantly evolved and now play a crucial role in addressing local environmental health issues and supporting local government policies. Their capacity to adapt and respond to region-specific challenges is essential for the effective implementation of environmental health policies, reflecting geographical, socioeconomic, and demographic differences.
9.Identification of new biomarkers of hepatic cancer stem cells through proteomic profiling
Sung Hoon CHOI ; Ha Young LEE ; Sung Ho YUN ; Sung Jae JANG ; Seung Up KIM ; Jun Yong PARK ; Sang Hoon AHN ; Do Young KIM
Journal of Liver Cancer 2025;25(1):123-133
Background:
s/Aims: In hepatocellular carcinoma (HCC), which exhibits high mortality and recurrence rates globally, the traits of cancer stem cells (CSCs) that significantly influence recurrence and metastasis are not well understood. CSCs are self-renewing cell types identified in most liquid and solid cancers, contributing to tumor initiation, growth, resistance, recurrence, and metastasis following chemo-radiotherapy or trans-arterial chemoembolization therapy.
Methods:
CSCs are classified based on the expression of cell surface markers such as CD133, which varies depending on the tumor type. Proteomic analysis of liver cancer cell lines with cancer stem cell potential and HCC cancer cell lines lacking stem cell propensity was conducted to compare and analyze specific expression patterns.
Results:
Proteomic profiling and enrichment analysis revealed higher expression of the calcium-binding protein S100 family in CD133+ Huh7 cells than in CD133- or wild-type cells. Furthermore, elevated expression of S100 family members was confirmed in an actual CD133+ liver cancer cell line via protein-protein network analysis and quantitative polymerase chain reaction (qPCR).
Conclusion
The S100 family members are not only new markers of cancer stem cells but will also assist in identifying new treatment strategies for CSC metastasis and tumor advancement.
10.Who Dies Alone? Demographics, Underlying Diseases, and Healthcare Utilization Patterns of Lonely Death Individuals in Korea
Haibin BAI ; Jae-ryun LEE ; Min Jung KANG ; Young-Ho JUN ; Hye Yeon KOO ; Jieun YUN ; Jee Hoon SOHN ; Jin Yong LEE ; Hyejin LEE
Journal of Preventive Medicine and Public Health 2025;58(2):218-226
Objectives:
Lonely death is defined as “a person living in a state of social isolation, disconnected from family, relatives, and others, who dies from suicide, illness, or other causes”. This study investigated the characteristics of individuals who die alone in Korea.
Methods:
We constructed a database of lonely death cases by linking data from the Korea Crime Scene Investigation Unit of the Korea National Police Agency with National Health Insurance Service (NHIS) records. A descriptive analysis was performed to evaluate the demographics, underlying diseases, and healthcare utilization patterns among lonely death cases.
Results:
Among the 3122 individuals identified as lonely death cases, 2621 (84.0%) were male and 501 (16.0%) were female. The most common age group was 50-59 years (n=930, 29.8%). The NHIS covered 2161 individuals (69.2%), whereas 961 individuals (30.8%) were enrolled in Medical Aid (MA). The highest number of lonely deaths occurred in Seoul areas, with 1468 cases (47.0%). Mood disorders were diagnosed in 1020 individuals (32.7%), and various alcohol-related diseases, including alcoholic liver disease, were also observed. Outpatient visits increased leading up to death but declined in the final 3 months, while hospitalizations decreased and emergency room visits slightly increased.
Conclusions
Most lonely death cases involved male in their 50s, with a disproportionately high number of MA beneficiaries compared to the general population. Many of these individuals also experienced mental health issues or alcohol-related disorders. Preventing social isolation and strengthening social safety nets are critical to reducing the occurrence of lonely deaths.

Result Analysis
Print
Save
E-mail