1.Human induced pluripotent stem cell-cardiomyocytes for cardiotoxicity assessment: a comparative study of arrhythmiainducing drugs with multi-electrode array analysis
Na Kyeong PARK ; Yun-Gwi PARK ; Ji-Hee CHOI ; Hyung Kyu CHOI ; Sung-Hwan MOON ; Soon-Jung PARK ; Seong Woo CHOI
The Korean Journal of Physiology and Pharmacology 2025;29(2):257-269
Reliable preclinical models for assessing drug-induced cardiotoxicity are essential to reduce the high rate of drug withdrawals during development. Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have emerged as a promising platform for such assessments due to their expression of cardiacspecific ion channels and electrophysiological properties. In this study, we investigated the effects of eight arrhythmogenic drugs—E4031, nifedipine, mexiletine, JNJ303, flecainide, moxifloxacin, quinidine, and ranolazine—on hiPSC-CMs derived from both healthy individuals and a long QT syndrome (LQTS) patient using multielectrode array systems. The results demonstrated dose-dependent changes in field potential duration and arrhythmogenic risk, with LQTS-derived hiPSC-CMs showing increased sensitivity to hERG channel blockers such as E4031. Furthermore, the study highlights the potential of hiPSC-CMs to model disease-specific cardiac responses, providing insights into genetic predispositions and personalized drug responses.Despite challenges related to the immaturity of hiPSC-CMs, their ability to recapitulate human cardiac electrophysiology makes them a valuable tool for preclinical cardiotoxicity assessments. This study underscores the utility of integrating patientderived hiPSC-CMs with advanced analytical platforms, such as multi-electrode array systems, to evaluate drug-induced electrophysiological changes. These findings reinforce the role of hiPSC-CMs in drug development, facilitating safer and more efficient screening methods while supporting precision medicine applications.
2.Analysis of Changes in Relative Value Scale and Frequency of Surgery and Procedures in Surgery Departments Over the Past 18 Years: Secondary Publication
Jae Hoon CHO ; Sei Young LEE ; Seung Hoon LEE ; Seog-Kyun MUN ; Jung Hyun CHANG ; Chan-Soon PARK
Korean Journal of Otolaryngology - Head and Neck Surgery 2025;68(2):67-73
Background and Objectives:
The purpose of this study was to compare and analyze the 18- year change in the relative value scale (RVS) in otolaryngology in relation to other surgical departments so as to help make future policy decisions.Subjects and Method Data on RVSs and addition rates, the deparments of main managed care, frequency of practice, and number of specialists were collected for all surgeries and procedures conducted in 2004, 2008, 2013, 2018, and 2022. Among these, an analysis was conducted for nine surgical departments. The number of surgeries and procedure items, the median value of the RVS, and the usage amount (i.e., RVS of all items multiplied by the frequency of surgeries and procedures) were calculated.
Results:
Over the past 18 years, the increase in the number of surgeries, procedure items and RVS in otolaryngology has grown smaller than that in other surgical departments, and the usage has decreased very sharply; in essence, the usage per specialist has actually decreased compared to 18 years ago.
Conclusion
Compared to other departments, RVS in otorhinolaryngology has shown very little change over the past period of 18 years. It is necessary to reasonably increase the currently undervalued RVS in otorhinolaryngology, particularly focusing on surgeries and procedures.
3.Core Needle Biopsy May Predict Prognosis Preoperatively in Parotid Cancer
Jeong-Yeon JI ; Wonjae CHA ; Young Ho JUNG ; Soon-Hyun AHN ; Woo-Jin JEONG
Clinical and Experimental Otorhinolaryngology 2025;18(1):57-63
Objectives:
. Salivary gland tumors present a diagnostic challenge, with preoperative false-negative results frequently leading to an unexpected diagnosis of malignancy after parotidectomy. This study was conducted to explore the clinical utility of preoperative core needle biopsy (CNB) in diagnosing malignancies before primary parotidectomy and to assess the prognostic implications of CNB for parotid gland cancers.
Methods:
. This retrospective cohort study included 615 patients who underwent preoperative CNB and parotidectomy for primary parotid tumors from 2003 to 2023 at a tertiary referral hospital. Among these patients, 102 who were diagnosed with primary parotid malignancy following parotidectomy were examined regarding survival outcomes. Disease-free survival (DFS) and predictive factors were assessed through univariable and multivariable analyses. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of CNB were determined. These metrics were then compared to those of a separate cohort of 547 patients who underwent ultrasound-guided fine needle aspiration (FNA) and parotidectomy within the same timeframe.
Results:
. In the CNB group, the 5-year predicted DFS was 86.9% (95% CI, 79.2%–95.3%). Multivariable analysis identified male sex (hazard ratio [HR], 8.48; 95% CI, 1.05–68.76) and a CNB finding of malignancy (HR, 8.20; 95% CI, 1.01–66.15) as factors significantly associated with decreased DFS. CNB demonstrated significantly higher sensitivity (89.0%; 95% CI, 81.2%–94.4%) and NPV (97.6%; 95% CI, 95.7%–98.8%) compared to FNA, which had a sensitivity of 45.2% (95% CI, 33.5%–57.3%) and an NPV of 90.8% (95% CI, 87.7%–93.3%).
Conclusion
. Preoperative CNB may be predictive of parotid cancer prognosis. Patients receiving a diagnosis of malignancy on preoperative CNB demonstrated a worse prognosis compared to those with a “less-than-malignant” diagnosis. Additionally, CNB exhibited higher sensitivity than FNA in identifying malignancies of the parotid gland.
4.The kinetics of nucleolar precursor bodies clustering at the pronuclei interface: Positive correlations with the morphokinetic characteristics of cleaving embryos and euploidy in preimplantation genetic testing programs
Hwa Soon OH ; Jung Mi JANG ; Hye Jin YOON ; Chang Woo CHOO ; Kyung Sil LIM ; Jin Ho LIM ; Yong-Pil CHEON
Clinical and Experimental Reproductive Medicine 2025;52(2):150-156
Objective:
This study investigated potential relationships between the kinetics of nucleolar precursor bodies (NPBs) in the pronucleus and developmental morphokinetics and euploidy in human preimplantation genetic testing for aneuploidy (PGT-A) cycles.
Methods:
The morphokinetic analysis of 200 blastocysts obtained from 53 PGT-A cycles was performed retrospectively in a time-lapse incubator. At the time of pronuclear breakdown (PNBD), we categorized the blastocysts into two groups based on the kinetic degree of clustering NPBs at the interface of the two pronuclei: clustered NPBs (CL) and non-clustered NPBs (NCL). We then compared morphokinetic parameters, abnormal behavioral events, and the rate of aneuploidy between the two groups.
Results:
Pronuclear fading and the first cleavage occurred earlier in the NCL group than in the CL group. However, the initiation of blastocyst formation and blastocyst expansion was delayed in the NCL group relative to the CL group. No differences were found in the rate of abnormal cleavage events, such as multinucleation at the 2-cell stage, direct cleavage from one to three cells, and from two to five cells between the CL and NCL groups. However, the fragmentation rate at the 8-cell stage was higher in the NCL group than in the CL group (10.3% vs. 1.9%, p<0.05). Additionally, the euploid rate in the CL group was significantly higher than in the NCL group (37.9% vs. 12.4%, p<0.05).
Conclusion
These results demonstrate the effectiveness of combining NPB clustering at PNBD with morphokinetics as a parameter for selecting embryos with higher developmental potential in in vitro fertilization.
5.KASL clinical practice guidelines for the management of metabolic dysfunction-associated steatotic liver disease 2025
Won SOHN ; Young-Sun LEE ; Soon Sun KIM ; Jung Hee KIM ; Young-Joo JIN ; Gi-Ae KIM ; Pil Soo SUNG ; Jeong-Ju YOO ; Young CHANG ; Eun Joo LEE ; Hye Won LEE ; Miyoung CHOI ; Su Jong YU ; Young Kul JUNG ; Byoung Kuk JANG ;
Clinical and Molecular Hepatology 2025;31(Suppl):S1-S31
6.Risk Factors for Perforation in Endoscopic Treatment for Early Colorectal Cancer: A Nationwide ENTER-K Study
Ik Hyun JO ; Hyun Gun KIM ; Young-Seok CHO ; Hyun Jung LEE ; Eun Ran KIM ; Yoo Jin LEE ; Sung Wook HWANG ; Kyeong-Ok KIM ; Jun LEE ; Hyuk Soon CHOI ; Yunho JUNG ; Chang Mo MOON
Gut and Liver 2025;19(1):95-107
Background/Aims:
Early colorectal cancer (ECC) is commonly resected endoscopically. Perforation is a devastating complication of endoscopic resection. We aimed to identify the characteristics and predictive risk factors for perforation related to endoscopic resection of ECC.
Methods:
This nationwide retrospective multicenter study included patients with ECC who underwent endoscopic resection. We investigated the demographics, endoscopic findings at the time of treatment, and histopathological characteristics of the resected specimens. Logistic regression analysis was used to investigate the clinical factors associated with procedure-related perforations. Survival analysis was conducted to assess the impact of perforation on the overall survival of patients with ECC.
Results:
This study included 965 participants with a mean age of 63.4 years. The most common endoscopic treatment was conventional endoscopic mucosal resection (n=573, 59.4%), followed by conventional endoscopic submucosal dissection (n=259, 26.8%). Thirty-three patients (3.4%) experienced perforations, most of which were managed endoscopically (n=23/33, 69.7%). Patients who undergo endoscopic submucosal dissection-hybrid and precut endoscopic mucosal resection have a higher risk of perforation than those who undergo conventional endoscopic mucosal resection (odds ratio, 78.65 and 39.72, p<0.05). Procedure-related perforations were not associated with patient survival.
Conclusions
Perforation after endoscopic resection had no significant impact on the prognosis of ECC. The type of endoscopic resection was a crucial predictor of perforation. Large-scale prospective studies are needed to further investigate endoscopic resection of ECC.
7.Predicting Mortality and Cirrhosis-Related Complications with MELD3.0: A Multicenter Cohort Analysis
Jihye LIM ; Ji Hoon KIM ; Ahlim LEE ; Ji Won HAN ; Soon Kyu LEE ; Hyun YANG ; Heechul NAM ; Hae Lim LEE ; Do Seon SONG ; Sung Won LEE ; Hee Yeon KIM ; Jung Hyun KWON ; Chang Wook KIM ; U Im CHANG ; Soon Woo NAM ; Seok-Hwan KIM ; Pil Soo SUNG ; Jeong Won JANG ; Si Hyun BAE ; Jong Young CHOI ; Seung Kew YOON ; Myeong Jun SONG
Gut and Liver 2025;19(3):427-437
Background/Aims:
This study aimed to evaluate the performance of the Model for End-Stage Liver Disease (MELD) 3.0 for predicting mortality and liver-related complications compared with the Child-Pugh classification, albumin-bilirubin (ALBI) grade, the MELD, and the MELD sodium (MELDNa) score.
Methods:
We evaluated a multicenter retrospective cohort of incorporated patients with cirrhosis between 2013 and 2019. We conducted comparisons of the area under the receiver operating characteristic curve (AUROC) of the MELD3.0 and other models for predicting 3-month mortality. Additionally, we assessed the risk of cirrhosis-related complications according to the MELD3.0 score.
Results:
A total of 3,314 patients were included. The mean age was 55.9±11.3 years, and 70.2% of the patients were male. Within the initial 3 months, 220 patients (6.6%) died, and the MELD3.0had the best predictive performance among the tested models, with an AUROC of 0.851, outperforming the Child-Pugh classification, ALBI grade, MELD, and MELDNa. A high MELD3.0score was associated with an increased risk of mortality. Compared with that of the group with a MELD3.0 score <10 points, the adjusted hazard ratio of the group with a score of 10–20 pointswas 2.176, and that for the group with a score of ≥20 points was 4.892. Each 1-point increase inthe MELD3.0 score increased the risk of cirrhosis-related complications by 1.033-fold. The risk of hepatorenal syndrome showed the highest increase, with an adjusted hazard ratio of 1.149, followed by hepatic encephalopathy and ascites.
Conclusions
The MELD3.0 demonstrated robust prognostic performance in predicting mortality in patients with cirrhosis. Moreover, the MELD3.0 score was linked to cirrhosis-related complications, particularly those involving kidney function, such as hepatorenal syndrome and ascites.
8.Analysis of Changes in Relative Value Scale and Frequency of Surgery and Procedures in Surgery Departments Over the Past 18 Years: Secondary Publication
Jae Hoon CHO ; Sei Young LEE ; Seung Hoon LEE ; Seog-Kyun MUN ; Jung Hyun CHANG ; Chan-Soon PARK
Korean Journal of Otolaryngology - Head and Neck Surgery 2025;68(2):67-73
Background and Objectives:
The purpose of this study was to compare and analyze the 18- year change in the relative value scale (RVS) in otolaryngology in relation to other surgical departments so as to help make future policy decisions.Subjects and Method Data on RVSs and addition rates, the deparments of main managed care, frequency of practice, and number of specialists were collected for all surgeries and procedures conducted in 2004, 2008, 2013, 2018, and 2022. Among these, an analysis was conducted for nine surgical departments. The number of surgeries and procedure items, the median value of the RVS, and the usage amount (i.e., RVS of all items multiplied by the frequency of surgeries and procedures) were calculated.
Results:
Over the past 18 years, the increase in the number of surgeries, procedure items and RVS in otolaryngology has grown smaller than that in other surgical departments, and the usage has decreased very sharply; in essence, the usage per specialist has actually decreased compared to 18 years ago.
Conclusion
Compared to other departments, RVS in otorhinolaryngology has shown very little change over the past period of 18 years. It is necessary to reasonably increase the currently undervalued RVS in otorhinolaryngology, particularly focusing on surgeries and procedures.
9.Giardia intraflagellar transport protein 88 is involved in flagella formation
Hye Rim YEO ; Mee Young SHIN ; Juri KIM ; Soon-Jung PARK
Parasites, Hosts and Diseases 2025;63(1):12-24
Intraflagellar transport (IFT) particles, a multi-protein apparatus composed of complex A and B, are known to be involved in homeostasis of flagella formation. IFT particles have recently become an interesting topic in Giardia lamblia, which has 4 pairs of flagella. In this experiment, we examined the function of giardial IFT components. When 7 components (IFT121, 140, 20, 46, 52, 81, and 88) of IFT were expressed in Giardia trophozoites as a tagged form with mNeonGreen, all of them were found in both flagella pores and cytoplasmic axonemes. In addition, motor proteins for IFT particles (kinesin-13 and kinesin-2b), were localized to a median body and cytoplasmic flagella, respectively. The CRISPRi-mediated knockdown of IFT88 significantly affected the lengths of all 4 flagella compared to the control cells, Giardia expressing dead Cas9 using control guide RNA. Decreased expression of kinesin-2b also resulted in shortening of flagella, excluding the ventral flagella. Live Giardia cells expressing IFT88-mNeonGreen clearly demonstrated fluorescence in flagella pores and cytoplasmic axonemes. These results on IFT88 and kinesin-2b indicate that IFT complex plays a role in maintenance of G. lamblia flagella.
10.Human induced pluripotent stem cell-cardiomyocytes for cardiotoxicity assessment: a comparative study of arrhythmiainducing drugs with multi-electrode array analysis
Na Kyeong PARK ; Yun-Gwi PARK ; Ji-Hee CHOI ; Hyung Kyu CHOI ; Sung-Hwan MOON ; Soon-Jung PARK ; Seong Woo CHOI
The Korean Journal of Physiology and Pharmacology 2025;29(2):257-269
Reliable preclinical models for assessing drug-induced cardiotoxicity are essential to reduce the high rate of drug withdrawals during development. Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have emerged as a promising platform for such assessments due to their expression of cardiacspecific ion channels and electrophysiological properties. In this study, we investigated the effects of eight arrhythmogenic drugs—E4031, nifedipine, mexiletine, JNJ303, flecainide, moxifloxacin, quinidine, and ranolazine—on hiPSC-CMs derived from both healthy individuals and a long QT syndrome (LQTS) patient using multielectrode array systems. The results demonstrated dose-dependent changes in field potential duration and arrhythmogenic risk, with LQTS-derived hiPSC-CMs showing increased sensitivity to hERG channel blockers such as E4031. Furthermore, the study highlights the potential of hiPSC-CMs to model disease-specific cardiac responses, providing insights into genetic predispositions and personalized drug responses.Despite challenges related to the immaturity of hiPSC-CMs, their ability to recapitulate human cardiac electrophysiology makes them a valuable tool for preclinical cardiotoxicity assessments. This study underscores the utility of integrating patientderived hiPSC-CMs with advanced analytical platforms, such as multi-electrode array systems, to evaluate drug-induced electrophysiological changes. These findings reinforce the role of hiPSC-CMs in drug development, facilitating safer and more efficient screening methods while supporting precision medicine applications.

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