1.Impact of third cleavage timing on blastulation and miRNA-429 expression in cryopreserved mouse embryos
Ye Eun LEE ; Jihyun KIM ; Jaewang LEE ; Jin Hyun JUN
Clinical and Experimental Reproductive Medicine 2026;53(2):128-136
Objective:
The aims of this study were to assess embryonic development using a time-lapse monitoring system based on cleavage timing and the use of vitrification and to investigate the correlation between miRNA-429 expression and embryonic development in both fresh and vitrified-thawed embryos.
Methods:
Mouse embryos at the 1-cell stage were collected and randomly divided into fresh and vitrified-thawed groups. The embryos were monitored and further subdivided into early and delayed cleavage based on the timing of the third cleavage event at 55 hours after human chorionic gonadotropin injection. miRNA-429 extracted from spent media or embryos cultured in vitro was analyzed by quantitative reverse transcription-polymerase chain reaction.
Results:
Early cleavage was associated with a significantly higher blastulation rate, regardless of cryopreservation status. Notably, among vitrified-thawed embryos, outgrowth was greater in those exhibiting early cleavage compared to those with delayed cleavage. Furthermore, miRNA-429 expression was elevated in embryos exhibiting delayed cleavage, but only within the cryopreserved group.
Conclusion
Based on these findings, we suggest that the timing of the third cleavage event may be more critical than the vitrification process itself, and evaluating miRNA-429 expression could serve as an alternative non-invasive selection tool for vitrified surplus embryos.
2.Nicotinamide ameliorates lipopolysaccharide-induced impairment of trophoblastic spheroid outgrowth in an in vitro implantation model
Wontae KIM ; Inyoung KANG ; Wonmo LEE ; Jaewang LEE ; Jin Hyun JUN
Clinical and Experimental Reproductive Medicine 2026;53(2):137-146
Objective:
Lipopolysaccharide (LPS), derived from various infectious bacteria in the uterus, interferes with communication between embryonic trophoblasts and endometrial cells, thereby inhibiting successful embryo implantation. This study aimed to investigate the effects of LPS and the anti-inflammatory compound nicotinamide (NAM) on early embryo implantation processes, focusing on the adhesion and outgrowth between trophoblast spheroids and endometrial cells.
Methods:
We used JAr mixed JEG-3 (JmJ) spheroids, prepared by combining JAr and JEG-3 cells in a 1:1 ratio. Following treatment with LPS with or without NAM, the attachment and outgrowth of JmJ spheroids on endometrial epithelial cells (ECC-1) were assessed. Additionally, changes in the gene expression of inflammatory cytokines (chemokine (C-X-C motif) ligand 1 [CXCL1], interleukin 8 [IL-8], and IL-33) and cell adhesion molecules (integrin alpha-V [ITGαV], integrin beta 3 [ITGβ3], and integrin beta 5 [ITGβ5]) in ECC-1 cells following LPS and/or NAM treatment were evaluated using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot analysis.
Results:
Decreased attachment rates and reduced outgrowth areas caused by LPS treatment were significantly restored by NAM. These restorative effects of NAM were associated with the modulation of inflammatory cytokines—specifically CXCL1 and IL-33, as shown by qRT-PCR—and expression of the cell adhesion molecule ITGβ3, as indicated by Western blot analysis.
Conclusion
Our study confirmed that LPS-induced endometrial infection may inhibit embryo implantation. NAM treatment ameliorated the detrimental effects of LPS by modulating the expression of inflammatory cytokines and adhesion molecules. Further studies are needed to explore the potential use of NAM as an effective additive to improve embryo implantation rates in human in vitro fertilization-embryo transfer programs.
3.Transformation of Pleomorphic Xanthoastrocytoma with Germline ATM Mutation into a SMARCB1-Deficient Rhabdoid Tumor: A Case Report
Hyeonseung LEE ; Hyun Jin PARK ; Bo Kyung KIM ; Kyung Taek HONG ; Hyoung Jin KANG ; Sung-Hye PARK ; Ji Hoon PHI ; June-Young KOH ; Jung Yoon CHOI
Clinical Pediatric Hematology-Oncology 2026;33(1):34-38
Secondary rhabdoid tumors (RTs) with atypical teratoid/rhabdoid tumor-like features rarely arise from, or coexist with, pleomorphic xanthoastrocytomas (PXAs), and their clinicopathological and molecular characteristics remain poorly understood. We report a 17-year-old girl with a temporal lobe mass that, upon gross total resection, pathologically contained both RT and PXA components. Immunohistochemistry revealed loss of INI1 expression restricted to the RT component, while the PXA area retained INI1. Next-generation sequencing identified a shared BRAF::TRIM24 fusion and homozygous deletion of CDKN2A/2B in both components, indicating a shared clonal origin. Additionally, a germline ATM frameshift mutation (c.5288_5289insGA) was identified in both tumor components, making the first such report in central nervous system tumors. SMARCB1 loss was confined to the RT component, further supporting the hypotheses of clonal evolution and secondary transformation. Despite gross total resection, craniospinal irradiation, and chemotherapy, the patient developed rapid leptomeningeal dissemination and died 5 months after surgery. This case provides clinicopathological and molecular evidence for clonal evolution and secondary transformation of PXA into an RT. The presence of germline ATM mutation may have therapeutic and biological relevance. Further studies are required to clarify the pathogenesis and optimal management of these rare and aggressive tumors.
4.The Clinical Effect of Trochlear Dysplasia on Medial Patellofemoral Ligament Reconstruction:Supratrochlear Spur and Lateral Inclination
Jin-Gyu KIM ; Junwoo BYUN ; Min JUNG ; Kwangho CHUNG ; Hyun-Soo MOON ; Se-Han JUNG ; Chong-Hyuk CHOI ; Sung-Hwan KIM
Clinics in Orthopedic Surgery 2026;18(1):52-62
Background:
The Dejour classification is widely accepted for grading the severity of trochlear dysplasia. However, whether it serves as a reliable prognostic marker for patellar instability surgery or a guide for clinical decision-making has yet to be established. Medial patellofemoral ligament (MPFL) reconstruction, with or without tibial tubercle osteotomy (TTO), yields comparable outcomes across Dejour grades. Nonetheless, we hypothesized that specific trochlear parameters would be more significant predictors of surgical results.
Methods:
This study included patients who underwent MPFL reconstruction, with or without TTO, for recurrent patellar dislocation at a single institution between 2010 and 2023. Patients with at least 1 year of follow-up were included. Preoperative demographics, radiographic measurements such as sulcus angle, lateral trochlear inclination (LTI), and trochlear depth, patient-reported outcome measures (PROMs), and intraoperative findings including cartilage status were analyzed. Severe trochlear dysplasia (STD) was categorized as Dejour B/D, while non-STD encompassed all other cases, and these 2 groups were compared. Postoperative PROMs were assessed at 1 year postoperatively and at the final follow-up. A noninferiority test was performed using Kujala, Lysholm, and International Knee Documentation Committee (IKDC) scores, with the inferiority margin defined by the minimal clinically important difference (MCID). Linear relationships between LTI, a widely used indicator of trochleoplasty, and PROMs were evaluated. Additionally, differences in the proportion of patients achieving MCID, substantial clinical benefit, and patient-acceptable symptom state were analyzed using odds ratios.
Results:
Forty-two knees (41 patients) were finally enrolled. Radiographic measurements, except for LTI at the most proximal trochlea, showed no significant differences between the STD and non-STD groups. Clinical outcomes also demonstrated no significant differences between the 2 groups, and noninferiority was confirmed. When analyzed based on LTI, no differences in PROMs were observed at the postoperative 1 year. However, at the final follow-up (mean, 37.27 months), the most proximal trochlear LTI showed significant correlations with both Kujala and Knee Injury and Osteoarthritis Outcome Score over the follow-up period.
Conclusions
MPFL reconstruction, with or without TTO, leads to similar clinical improvements for STD classified by Dejour criteria. However, when assessed using proximal LTI, dysplasia’s role as a prognostic factor should be considered.
5.Sonographic Evaluation of Tendinous Mallet Finger to Estimate the Extent of Extension Lag
Jin Young KIM ; Jin Bog LEE ; Tae Hyun KIM
Clinics in Orthopedic Surgery 2026;18(1):133-140
Background:
Although several reports have addressed tendinous mallet finger (TMF), they have not identified which method best informs surgeons about the extent of residual extension lag in these patients. We aimed to assess the association between sonographic classification of acute TMF and the degree of extension lag remaining at the final follow-up.
Methods:
The inclusion criterion was acute TMF with symptom onset within 2 weeks. Thirty-eight patients (23 male and 15 female) participated, with a mean follow-up of 17.1 months (range, 12.3–23.5 months). Range of motion, including extension lag, was measured at both the initial presentation and the final follow-up. All patients were managed conservatively using a finger splint for a period exceeding 6 weeks. Ultrasonography was performed for all participants to assess the severity of terminal extensor tendon injury. Statistical analyses examined the relationship between sonographic type and extension lag at final follow-up.
Results:
At initial presentation, the mean extension lag was 46.0°, which improved to 17.5° at the last follow-up. TMF cases were categorized into 3 sonographic types (hypo-echoic, thinned, and wavy) based on ultrasound characteristics. A significant difference in extension lag at final follow-up was observed among the TMF groups (p = 0.005). Patients with the wavy type had the greatest mean extension lag, whereas those with the hypo-echoic type had the least mean extension lag, with statistical significance.
Conclusions
Sonographic assessment of TMF can aid in predicting residual extension lag in patients with TMF undergoing conservative treatment with a finger splint.
6.Whole-Exome Sequencing Improves Risk Assessments of Adult Moyamoya Disease
Eun Pyo HONG ; Eun Jin HA ; Dong Hyuk YOUN ; Yuwhan CHUNG ; Kang Min KIM ; Sung Ho LEE ; Won-Sang CHO ; Hyun-Seung KANG ; Jin Pyeong JEON ; Jeong Eun KIM ;
Journal of Clinical Neurology 2026;22(2):160-172
Background:
and Purpose Whole-exome sequencing (WES) is a valuable tool for identifying causative mutations in adult moyamoya disease (MMD), thereby advancing our understanding of the genetic mechanisms underlying this condition. Here, we conducted the first WESbased association study aimed at identifying genetic modifiers implicated in MMD.
Methods:
This WES study involved 160 patients with MMD and 189 controls from a multicenter hospital-based biobank, and evaluated combined annotation-dependent depletion (CADD) scores. Mutant-allele frequencies were compared in 369,121 individuals derived from the UK Biobank (UKB) WES. Mutant-allele risk scores (MARSs) were created based on WESidentified mutations. Gene-based association analyses and pooled analyses in East-Asian populations were further performed.
Results:
Fourteen mutations reached the genome-wide significance criterion (p<5×10-8 ), among which the p.R4810K mutation in the ring finger protein 213 gene (RNF213) showed the strongest significance (odds ratio=117.4, p=8.54×10-24 ). Notably, two mutations—p.G576S (alpha-glucosidase [GAA]) and p.D54N (charged multivesicular body protein 6 [CHMP6])— exhibited high CADD scores of 32 and 25, respectively, whereas the RNF213 p.R4810K mutation demonstrated a moderate deleteriousness score of 10.63. Fourteen mutations exhibited significant differences in allele frequencies between patients and UKB controlled data (p<1×10-8 ).The MARS9 model (incorporating nine missense mutations) showed better predictability for MMD (90.89%). The analysis of gene-based associations revealed four candidate genes: GAA, RNF213, CHMP6, and CARD14 (p=5×10-19 to 4×10-7 ). The subsequent pooled analyses validated four mutations in East Asian populations: p.V1195M, p.D1331G, p.S2334N, and p.R4810K (p<3×10-8 ).
Conclusions
This pioneering study has corroborated the significance of p.R4810K and identified several causative mutations predisposing patients to MMD, which helps to improve the understanding of its polygenetic nature.
7.Clinical Characteristics and Outcomes of Life-sustaining Treatment Withdrawal in a Korean Neurocritical Care Unit: A Single-center Retrospective Study
Junho SEONG ; Hye-in CHUNG ; Jin-Heon JEONG ; Jung Hwa SEO ; Dae-Hyun KIM ; Yong-Hwan CHO ; Jae Hyung CHOI ; Jae-Kwan CHA
Journal of the Korean Neurological Association 2026;44(1):47-53
Background:
The Act on Decisions on Life-Sustaining Treatment (LST) has been implemented in Korea since 2018, yet data on its application in neurocritical care units remain scarce. This study aimed to evaluate the clinical characteristics and outcomes of LST withdrawal or withholding in the neurocritical care unit.
Methods:
This study was a retrospective analysis conducted at a tertiary university hospital in Busan, South Korea. Among patients admitted to the neurocritical care unit between February 2018 and August 2023, those with documented decisions for LST withdrawal or withholding were enrolled. Demographic and clinical characteristics, underlying and combined conditions, reasons for LST decisions, measures taken, and time from LST withdrawal to death were extracted from medical records.
Results:
A total of 69 patients were included, with a median age of 67 years, and 38 (55%) were male. Cerebrovascular disease (62%) and traumatic brain injury (22%) were the most common underlying diagnoses. The primary reason for LST decisions was irreversible neurological damage (71%), followed by systemic complications (19%). Mechanical ventilation cessation (91%) and extubation (86%) were most frequently used measures for LST withdrawal. The median time from LST withdrawal to death was 22 minutes.
Conclusions
Our study demonstrates that LST decisions in the neurocritical care unit predominantly occur among patients with cerebrovascular disease or traumatic brain injury, mostly triggered by neurological deterioration. Most patients died shortly after withdrawal. These findings provide important insight into current LST withdrawal practices in neurocritical care and may assist clinical and ethical decision making in similar settings.
8.Fetal development of chromogranin A-positive gastrointestinal endocrine cells revisited: a histological study using human fetuses
Ji Hyun KIM ; Zhe-Wu JIN ; Eri MIYAMOTO ; Sakiko TAKAHASHI ; Sayako SUZUKI ; Gen MURAKAMI ; Shin-ichi ABE
Anatomy & Cell Biology 2026;59(1):82-93
Initial gastrointestinal endocrine cells (GIECs) likely appear at the proximal and distal sites of abdominal intestines and may take a close topographical relation with neural elements in the gut. We examined immunohistochemically-stained sections from 10 fetuses at approximately 8–18 weeks of gestational age (36–155 mm of crown-rump length). Irrespective of whether physiological herniation was present (early 5 specimens) or absent (the other 5), the duodenum and jejunum had well-developed mucosa with villi containing abundant flask-like chromogranin-positive cells. In the earlier 5 specimens, the rectum, standing up to a level of the umbilicus, had a lumen and villi with a few positive cells, but the colon carried neither the lumen or chromogranin-positive cells. The initial GIECs seemed to appear in the basal payer of the epithelium at the distal and proximal foci depending on double pathways of neural crest cell migration. Less number of the colic chromograninpositive cells, more than 5-times difference in density relative to small intestine, was seen in the larger 5 specimens. The appearance of GIECs was delayed at the anal transitional zone (a border area between the columnar and squamous epithelia).The reactivity of neuronal nitric oxide synthase was restricted in the myenteric plexus, whereas clusters of slender calretininpositive cells existed in the lamina propria or core of villi in the duodenum and colon. Relatively small, round or oval positive cells were also seen in the basal layer of the columnar epithelium. Therefore, calretinin-positive cells might exist closely to GIECs in the developing villi.
9.The Korean Rectal Cancer Multidisciplinary Committee Clinical Practice Guidelines for Rectal Cancer version 2.0
Hyo Seon RYU ; Hyun Jung KIM ; Dong Hyun KANG ; Yoo-Kang KWAK ; Han Deok KWAK ; Yoon-Hye KWON ; Dalyon KIM ; Baek-Hui KIM ; Jae Hyun KIM ; Ji Hun KIM ; Jin Won KIM ; Tae Hyung KIM ; Hae Young KIM ; Soo Min NAM ; Gyoung Tae NOH ; Jun Woo BONG ; Nak Song SUNG ; Seon Hui SHIN ; Kil-Yong LEE ; Sung Chul LEE ; Sea-Won LEE ; Jung Won LEE ; Jong Min LEE ; Myung Hoon IHN ; Joo Han LIM ; Woong Bae JI ; Dae Hee PYO ; Young Ki HONG ; Jung-Myun KWAK ;
Annals of Coloproctology 2026;42(1):4-33
Rectal cancer, which accounts for approximately 40% of colorectal cancers, remains a major clinical concern. Recent advances in diagnostic imaging, surgical techniques, radiotherapy, and systemic treatment have steadily improved rectal cancer outcomes. Considering this, the Korean Rectal Cancer Multidisciplinary (KRCM) Committee has aimed to provide clinicians and policymakers with up-to-date, evidence-based clinical practice guidelines to support optimal decision-making, reflecting current evidence, the Korean healthcare context, and patient values and preferences. The Clinical Practice Guidelines for Rectal Cancer version 2.0 were developed through multidisciplinary collaboration with related academic societies, building upon and updating the KRCM Clinical Practice Guidelines version 1.0 (titled “Multidisciplinary guidelines for the management of rectal cancer”). These consensus guidelines of the KRCM were established based on a comprehensive literature review, evidence synthesis, with recommendation development guided by the GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology, and consideration of applicability in real-world clinical practice under the national health insurance system. Each recommendation has been presented with its strength and level of evidence.
10.Peak and Trough Concentration Ranges of Factor Xa Inhibitors for Preventing Thromboembolic Stroke in Korean Patients with Non-valvular Atrial Fibrillation
Jong-Sung PARK ; Kyung Hee LIM ; Dae-Hyun KIM ; Kwang-Min LEE ; Kwang-Sook WOO ; Jin-Yeong HAN
Annals of Laboratory Medicine 2026;46(1):32-40
Background:
Current guidelines recommend factor IIa- or Xa-specific inhibitors over warfarin analogs for preventing thromboembolic stroke in patients with atrial fibrillation (AF).However, their plasma concentrations in Korean patients are not well understood.
Methods:
We conducted a single-center laboratory study to determine the distribution ranges of peak and trough concentrations of three factor Xa inhibitors (apixaban, edoxaban, and rivaroxaban) prescribed for preventing strokes in patients with AF. Patients receiving one of these drugs and undergoing blood specimen collection for laboratory tests were screened. Blood specimens were obtained from patients who had adhered to the prescribed drug regimen consistently for at least 1 week. Drug plasma concentrations were measured using heparin liquid-reagent technology-based anti-Xa chromogenic assays.
Results:
We selected 459 patients who were taking standard or on-label-reduced doses of apixaban (N = 252), edoxaban (N = 182), or rivaroxaban (N = 25). The 5th–95th percentile ranges of the peak concentrations were 84–414 ng/mL (apixaban), 72–424 ng/mL (edoxaban), and 97–517 ng/mL (rivaroxaban). The respective 5th–95th percentile ranges of the trough concentrations were 44–237 ng/mL, 23–93 ng/mL, and 13–219 ng/mL. Approximately 19.6% (apixaban), 33.3% (edoxaban), and 64.0% (rivaroxaban) of patients in each group had peak concentrations out of the predicted distribution ranges based on pharmacokinetic data. Approximately 7.3%, 52.8%, and 8.3% of patients had trough concentrations out of the predicted distribution ranges.
Conclusions
A considerable proportion of Korean patients with AF taking factor Xa inhibitors may require population-specific reference ranges to guide therapeutic monitoring.

Result Analysis
Print
Save
E-mail