1.Online DPPH Assay Coupled with LC-QTOF-MS for Rapid Identification of Antioxidant Constituents from Zelkova serrata
Ngoc Khanh VU ; Chang Jung KIM ; Soo Min KIM ; Young Jun KIM ; Kyeong Seon LEE ; Ki Yong LEE
Natural Product Sciences 2026;32(1):29-37
Zelkova serrata (Thunb.) Makino is a deciduous tree commonly distributed in East Asia. Several investigations have documented the biological activity of extracts of this species, igniting increased interest in its therapeutic potential. However, the phytochemical constituents accountable for these activities remain largely unexplored. In this study, we focused on the antioxidant potential of the leaves and twigs, utilizing bioactivityguided fractionation combined with LC-QTOF-MS online DPPH screening to systematically identify the active compounds. This approach led to the isolation of eight compounds, three of which (compounds 1, 3, and 7) have not previously been documented in the genus Zelkova. Among the isolates, 4 emerged as the most potent antioxidant, exhibiting significant radical scavenging activity in both DPPH (IC 50 = 13.67 ± 1.21 μM) and ABTS (IC50 = 2.69 ± 0.48 μM) assays, exceeding ascorbic acid (IC 50 = 61.51 ± 10.22 μM) and trolox (IC50 = 8.22 ± 2.16 μM), respectively. Our findings not only enrich the phytochemical profile of Z. serrata but also highlight the effectiveness of LC-MS-DPPH as an effective approach for rapid antioxidant discovery.
2.Improving prediction of ypT0–1N0 response in rectal cancer: the added value of gross tumor type to magnetic resonance tumor regression grade after chemoradiotherapy in a retrospective cohort study
Kyong-Min KANG ; Mi-Jeong CHOI ; Hong-min AHN ; Heung-Kwon OH ; Duck-Woo KIM ; Jungheum CHO ; Won CHANG ; Young Hoon KIM ; Kyoung Ho LEE ; Yu Kyung JUN ; Yonghoon CHOI ; Sung-Bum KANG
Annals of Surgical Treatment and Research 2026;110(4):237-245
Purpose:
While MRI-based tumor regression grade (mrTRG) has shown promise in evaluating pathologic response to concurrent chemoradiotherapy (CCRT) in rectal cancer, its ability to predict pathologic complete response remains limited.This study aimed to enhance mrTRG’s diagnostic performance in predicting ypT0–1N0 status, a key factor in considering non-radical management after CCRT for locally advanced rectal cancer (LARC).
Methods:
This retrospective study included 430 patients with LARC who underwent radical resection following CCRT at a single referral hospital between April 2018 and September 2024. Multivariable logistic regression was used to identify predictive factors associated with achieving ypT0–1N0 status. The diagnostic performances of mrTRG1–2 alone and in combination with other factors were assessed by comparing sensitivity, specificity, positive-predictive value (PPV), negative-predictive value, and area under the curve (AUC).
Results:
Ninety-three patients (21.6%) achieved ypT0–1N0. In the multivariable analysis, fungating type, cT1–2, and mrTRG1–2 were independent predictors for ypT0–1N0. Integrating mrTRG with gross tumor type yielded the highest AUC of 0.689 among the combined models. For predicting ypT0–1N0, the combination of mrTRG and gross tumor type improved PPV (79.2% vs. 41.5% for mrTRG alone) while also demonstrating enhanced sensitivity compared with ycT0–1N0, the conventional MRI-based predictor (40.9% vs. 22.6%).
Conclusion
This study demonstrated that combining mrTRG and gross tumor type improved the PPV of mrTRG in predicting ypT0–1N0 after CCRT in LARC. Further studies are warranted to validate the role of gross tumor type in refining predictive systems for selecting candidates for non-radical treatment.
3.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.
4.Anticancer Treatment Influences TREM2 in Tumor-Associated Macrophages in Lung Cancer
Yoon Jin CHA ; Eun Hye LEE ; Chi Young KIM ; Yong Jun CHOI ; Min Kyung PARK ; Sang Hoon LEE ; Eun Young KIM ; Yoon Soo CHANG
Cancer Research and Treatment 2026;58(2):465-480
Purpose:
The triggering receptor expressed on myeloid cells 2 (TREM2) creates an immunosuppressive environment, but the effects of anticancer treatment on TREM2 and the tumor microenvironment (TME) are not well established. This study investigates the impact of chemotherapy on TREM2-expressing macrophages within the lung adenocarcinoma TME.
Materials and Methods:
Using single-cell RNA sequencing datasets of paired normal-appearing lung tissue (NL) and tumor (Tu), human and mouse lung cancer tissue, and THP-1 cells, we observed the effects of anticancer drugs on them.
Results:
Myeloid cells (MY) were the second-most abundant non-epithelial component in the Tu, though less prevalent than in NL. Specific MY subclusters abundant in Tu showed overexpression of TREM2. In lung cancer-induced Kras-G12D mice, M2 proportion increased in Tu compared to NL; cisplatin increased TREM2+ M2 proportion in Tu. TREM2+ cells in Tu showed interactions with cell clusters showing characteristics of interstitial macrophage such as mo-lineage, mono-Mc, and CD163/LGMN cells via FN:CD44 and MIF:CD74+CXCR4, suggesting that they influence the recruitment of those cells to Tu and TME reshape. In M0-state THP-1 cells, cisplatin and osimertinib treatments induced polarization towards M1 and M2 states and increased TREM2 expression. Cisplatin promoted uptake of phosphatidylserine-coated latex beads by M0 cells, whereas osimertinib reduced uptake by polarized macrophages. These findings suggest anticancer treatments impact the lung immune microenvironment by altering the TREM2+ cells.
Conclusion
Given TREM2’s central inhibitory role in the tumor immune environment, effects of chemotherapeutic agents should be considered in developing TREM2-targeting therapies.
5.Survival Rates of Patients with Gastric Cancer According to Age and Sex: A Large-Scale Study Using Data from 14,739 Patients
Yonghoon CHOI ; Nayoung KIM ; Ji Hyun KIM ; Hyeong Ho JO ; Hyeon Jeong OH ; Hye Seung LEE ; Yu Kyung JUN ; Hyuk YOON ; Cheol Min SHIN ; Young Soo PARK ; Dong Ho LEE ; So Hyun KANG ; Young Suk PARK ; Sang-Hoon AHN ; Yun-Suhk SUH ; Do Joong PARK ; Hyung Ho KIM ; Ji-Won KIM ; Jin Won KIM ; Keun-Wook LEE ; Won CHANG ; Yoon Jin LEE ; Kyoung Ho LEE ; Young Hoon KIM
Cancer Research and Treatment 2026;58(1):252-263
Purpose:
The male predominance in the incidence of gastric cancer (GC) is established; however, sex differences in the prognosis of GC remain controversial. As such, this study analyzed the prognosis of patients with GC based on age and sex.
Materials and Methods:
Data from 14,739 patients diagnosed with GC at Seoul National University Bundang Hospital between 2003 and 2023 were analyzed. Baseline characteristics, histological types of GC, overall and GC-specific survival rates (age and stage stratification), and associated risk factors were analyzed.
Results:
Females were significantly younger (p < 0.001) and exhibited more gastric body cancers (p < 0.001) and tumors with diffuse-type or poorly differentiated histology (p < 0.001) than males. Females exhibited an advantage over males in terms of overall survival (p=0.004), but not in GC-specific survival. However, age stratification revealed significant sex differences, that females < 50 years of age exhibited survival disadvantages (p < 0.001); however, this trend was reversed with age, and females > 60 years exhibited survival advantages (p < 0.001) for both overall and GC-specific survival. This may be explained by the lower ratio of diffuse-type GC as females age. Furthermore, in the analysis according to stage, females with stage IV disease exhibited significant survival disadvantages, with significantly younger age and a higher proportion of diffuse-type GC which exhibits aggressive features, resulting in poorer survival than in males.
Conclusion
Age and stage stratification revealed significant differences in survival between the sexes, which can be helpful for public health strategies.
6.Guidelines for the Management of Adult Subglottic and Tracheal Stenosis From the Korean Bronchoesophagological Society
Jung-Hae CHO ; Gene HUH ; Jae-Keun CHO ; Jae Won CHANG ; Jun-Ook PARK ; Young Chan LEE ; Jae Hyun JEON ; Jeon Yeob JANG ; Byeong-Ho JEONG ; Yeon Soo KIM ; Inn-Chul NAM ; Gil Joon LEE ; Woo Sik YU ; Heejin KIM ; Minhyung LEE ; Ji Won KIM ; Seung Hoon WOO ; Il-Seok PARK ; Jin Pyeong KIM ;
Clinical and Experimental Otorhinolaryngology 2026;19(1):1-20
Subglottic stenosis (SGS) and tracheal stenosis (TS) are rare conditions that can cause significant breathing difficulties and, if not properly managed, may lead to life-threatening complications. Despite their clinical importance, debate continues regarding the optimal management of adult SGS and TS, and no comprehensive guidelines have been established to date. The Korean Bronchoesophagological Society appointed a task force to develop clinical practice guidelines with the goal of providing evidence-based recommendations for managing SGS and TS in adults. The task force conducted a systematic review of the relevant literature by searching PubMed, Embase, and the Cochrane Library using predefined search terms aligned with key clinical questions. The quality of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach, which also informed the formulation and reporting of the recommendations. The strength of each recommendation reflects the guideline panel’s confidence that the benefits of an intervention outweigh its risks for eligible patients. After drafting the guidelines, feedback was obtained through Delphi questionnaires completed by members of the Korean Bronchoesophagological Society. Ultimately, the committee developed 17 evidence-based recommendations across four categories: initial evaluation, medical management, surgical treatment, and postoperative management and rehabilitation. These guidelines aim to support clinicians in delivering optimal care to adult patients with SGS and TS.
7.L-Point Entry, Juxtapedicular, and Endplate-Parallel Trajectory (L-JET) Screw Fixation: A Novel Technique in Thoracic Spinal Tumor Surgery
Seunghoon LEE ; Young Rak KIM ; Chang-Hyun LEE ; Jungbo SIM ; Woojin KIM ; Ho Sung MYEONG ; Hangeul PARK ; Jun-Hoe KIM ; Chi Heon KIM
Journal of Minimally Invasive Spine Surgery and Technique 2026;11(1):6-13
Objective:
Thoracic pedicle screw fixation is technically demanding because of the natural variability in pedicle anatomy, a challenge that is further exacerbated in patients with spinal tumors who often have compromised pedicles. The L-point entry, juxtapedicular, and endplate-parallel trajectory (L-JET) technique was developed to provide a uniform entry point, a predictable screw trajectory, and the capacity to accommodate larger-diameter screws at levels T3–10. This study aimed to evaluate the safety and feasibility of the L-JET technique in comparison with the conventional transpedicular method.
Methods:
A comparative analysis of consecutively collected data was performed to evaluate outcomes associated with the L-JET technique in patients undergoing surgery for thoracic extradural spinal tumors. The L-point was defined as the intersection of a vertical line along the lateral margin of the facet joint and a horizontal line along the upper edge of the transverse process. The screw trajectory was planned with 30° of medial convergence in the axial plane, creating a juxtapedicular path, and a straightforward trajectory in the sagittal plane. Primary outcome measures included screw diameter, screw length, cortical breach rate, and the need for revision surgery, as assessed using computed tomography scans and medical records.
Results:
A total of 108 screws were placed in 22 patients using the L-JET technique, while 98 screws were placed in 18 patients using the conventional technique. The L-JET group used significantly larger-diameter screws (6.06±0.65 mm) than the conventional group (5.74±0.80 mm, p=0.02), with no significant difference observed in screw length between groups. Medial cortical breach occurred in one screw in each group, and no supra- or infrapedicular breaches were identified. No screw-related neurovascular complications or revision surgeries occurred in either group.
Conclusion
The L-JET technique enables consistent screw placement with larger-diameter screws, even in compromised pedicles associated with thoracic spinal tumors, without increasing the risk of complications or the need for revision surgery.
8.Development of an RGB-depth camera-based gait analysis system: a single-case study of a patient with stroke
Min Cheol CHANG ; Juyeon KIM ; Jun Sung MOON ; Wooktae PARK ; Gun Woo LEE ; Yoo Jin CHOO
Journal of Yeungnam Medical Science 2026;43(1):15-
Alterations in gait patterns often indicate health status, and their analysis enables the diagnosis and assessment of various health conditions. This study aimed to develop a noncontact gait analysis system using red, green, and blue-depth (RGB-D) cameras and to evaluate its potential clinical applicability. A single case study was conducted to assess changes in the gait patterns of a patient with stroke before and after the application of an ankle-foot orthosis. Twenty walking trials were recorded to evaluate the key gait parameters. The custom RGB-D camera-based gait analysis system demonstrated the potential to rapidly quantify key gait parameters in the patient. Compared with normative data, it effectively identified characteristic stroke-related gait impairments such as shorter step lengths and slower gait speeds. However, the intraclass correlation coefficient analysis indicated low measurement reliability. Although the stance time and minimum knee angle on the left and right sides exceeded the standard error of measurement (SEM), no changes exceeded the minimal detectable change (MDC) criteria. Moreover, other gait parameters did not show significant changes beyond SEM or MDC, limiting the interpretability of the results. Therefore, further technological developments and data collection are required to improve test-retest reliability and sensitivity to change.
9.Facet Effusion-Incorporating Grading System:A Modified Magnetic Resonance Imaging-Based Classification That Enhances Surgical Prognostication in Lumbar Foraminal Stenosis
Sung Taeck KIM ; Dong-Ho KANG ; Hyoungmin KIM ; Bong-Soon CHANG ; Jae Hun KIM ; Seonpyo JANG ; Jun-Yeop LEE ; Sam Yeol CHANG
Clinics in Orthopedic Surgery 2026;18(1):71-77
Background:
The conventional magnetic resonance imaging (MRI) grading system for foraminal stenosis (FS), known as the Lee classification, was introduced in 2010 and is widely utilized in clinical practice. Previous studies have reported that the conventional grading system for FS lacks prediction ability for surgical treatment. The purpose of this study was to develop a novel MRI grading system for lumbar FS with improved prediction ability for surgical treatment by incorporating facet effusion to indicate segmental instability.
Methods:
We retrospectively reviewed patients diagnosed with lumbar FS between 2011 and 2017 who had a follow-up period of at least 5 years. The FS severity was assessed using a conventional MRI grading system developed by Lee et al. We recorded whether the patient underwent surgical treatment for FS during the follow-up period and the time from the initial diagnosis to surgery. Survival analysis using a Kaplan-Meier curve and log-rank test was performed to verify the impact of FS severity on the surgical treatment. We performed additional survival analysis after modifying the grading system by incorporating the presence of excessive facet joint effusion assessed using axial MRI. We also compared the discrimination ability of the modified and conventional grading systems using Uno’s concordance index (C-index).
Results:
In total, 235 patients with a mean age of 63.7 years were included in this study. During the mean follow-up period of 8.1 years, 63 patients underwent surgical treatment for FS. The conventional grading system revealed no significant difference in survival between the grade 2 and 3 groups (p = 0.104). Conversely, the modified grading system revealed a significant difference in survival between the new grade 2 and 3 groups (p < 0.001). After modification, the discrimination ability, assessed using Uno’s Cindex, significantly improved from 0.69 to 0.73.
Conclusions
The Facet Effusion-Incorporating Grading System, which adds excessive facet joint effusion to the conventional MRI grading framework, demonstrated improved predictive value for surgical treatment and better discriminatory ability compared with the original system.
10.Mucosal Brush Sampling Increases the Helicobacter pylori Detection Rate of the Rapid Urease Test: A Pilot Study
Chang Seok BANG ; A In CHOI ; Jeong-Gyu CHOI ; Jae Jun LEE ; Eun Jeong GONG
Gut and Liver 2026;20(1):77-85
Background/Aims:
Accurate diagnosis of and timely eradication therapy for Helicobacter pylori are crucial for managing and preventing adverse clinical outcomes associated with H. pylori infection. H. pylori infection is typically diagnosed using endoscopic biopsy-based tests such as the rapid urease test (RUT). In this study, we investigated the usefulness of mucosal brush sampling for H. pylori detection using the RUT and culture.
Methods:
Twenty patients with H. pylori infection underwent endoscopy, and specimens were collected from the greater curvature of the gastric corpus via both mucosal brush and biopsy sampling methods. Brushing was performed using a disposable cytology brush, and the brush specimen was used for the RUT (brush-RUT) and then for culture. Two biopsies were obtained for the RUT (biopsy-RUT) and culture. H. pylori detection rates using RUT and culture yields from brush and biopsy samples were compared.
Results:
The H. pyloridetection rate was 100% with the brush-RUT, whereas it was 75% with the biopsy-RUT. Notably, among patients taking acid-suppressive agents, the sensitivity of the biopsy-RUT decreased to 66.7%, whereas that of the brush-RUT remained at 100%. The biopsy-RUT yield was also associated with the delta over baseline value determined by the urea breath test.H. pylori was successfully isolated from all the biopsy specimens and 95% of the brush samples, and all H. pylori isolates were tested for antimicrobial susceptibility. No significant procedurerelated adverse events occurred with either sampling method.
Conclusions
Mucosal brushing is a simple, effective, and highly sensitive diagnostic method for H. pylori infection. The mucosal brush method is a practical alternative to biopsy, expanding the diagnostic capabilities while minimizing invasiveness.

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