1.The impact of the laboratory quality management program on colorectal cancer screening using immunochemical fecal occult blood tests in Korea
Hye Ryun LEE ; Sollip KIM ; Hyeongsu KIM ; Yeo-Min YUN ; Ho Jin JEONG ; Minje HAN ; Myeong Hee KIM ; Tae-Hyun UM ; You Kyoung LEE ; Byung Ryul JEON ; Kunsei LEE ; Sail CHUN
Journal of the Korean Medical Association 2025;68(5):338-347
Purpose:
Immunochemical fecal occult blood tests (iFOBT) have been utilized as the primary method for colorectal cancer screening within Korea's National Cancer Screening Program. This study aimed to evaluate the impact of the accreditation program for clinical laboratories and external quality assessment (EQA) programs on colorectal cancer screening.
Methods:
We analyzed the false-positive rates of iFOBT in colorectal cancer screening from 2016 to 2020 according to participation and performance in the Outstanding Laboratory Accreditation Program (OLAP) conducted by the Laboratory Medicine Foundation, and the External Quality Assessment programs run by the Korean Association of External Quality Assessment Service.
Results:
False-positive rates of iFOBT were lower among institutions accredited by OLAP (2.35%) compared with non-accredited (3.04%) and non-participating institutions (5.60%). Similarly, institutions participating in the EQA program exhibited lower false-positive rates (3.79%) compared to non-participants (7.04%). Within the iFOBT-specific EQA program, institutions that passed demonstrated the lowest false-positive rate (3.37%), while failing institutions showed the highest rate (9.07%), surpassing even non-participating institutions (6.44%).
Conclusion
Participation in quality management programs such as OLAP and EQA was associated with lower false-positive rates in iFOBT for colorectal cancer screening. These findings suggest that quality management initiatives can increase the accuracy of iFOBT, potentially improving the effectiveness of colorectal cancer screening programs, and reducing unnecessary follow-up procedures and associated healthcare costs.
2.Nephrogenic diabetes insipidus secondary to COVID-19 infection in a patient on lithium medication: a case report
Jong-In CHOI ; Somin LEE ; Hyun Lee KIM ; Jong-Hoon CHUNG ; Byung Chul SHIN ; Youngmin YOON
Journal of the Korean Society of Emergency Medicine 2025;36(1):41-44
Nephrogenic diabetes insipidus (NDI) is characterized by polyuria and polydipsia, high serum osmolality, and low urine osmolality because of resistance to antidiuretic hormone. Lithium is commonly used to treat psychiatric disorders, and NDI is one of the common renal side effects of lithium therapy. On the other hand, NDI induced by lithium medication in a patient after a coronavirus disease-19 (COVID-19) infection has not been reported. This paper presents a patient who developed new-onset NDI secondary to a COVID-19 infection despite being on a stable lithium dose for several years. This case highlights the importance of considering a COVID-19 infection as a possible cause of NDI in patients taking lithium medication.
3.Association between Caffeinated Beverages Consumption and Sleep Quality of Urban Workers
Byung Il HWANG ; Ji-Young LEE ; Hyeon Jeong LIM ; Ryun HUH ; Mikyung RYU ; Sun Ha JEE ; Heejin KIMM
Korean Journal of Health Promotion 2025;25(1):9-19
Background:
The stimulatory effects of caffeine contribute to poor sleep quality. However, the relationship between caffeinated beverages and sleep quality, considering frequency or types of caffeinated beverages, were not extensively studied.
Methods:
Data were collected from 160 urban workers (75 men [46.9%] aged 20–69 years; with an average age of 41.8±12.3 years) using a structured, self-administered online questionnaire. Sleep quality, time, satisfaction; types and frequency of caffeinated beverages (number of cups per week; Q1: 0 cup, Q4: 14 or more cups per week), demographics, and health behaviors were asked. Sleep quality were evaluated using the Korean version of the Pittsburgh Sleep Quality Index (PSQI-K). Multiple regression analysis was conducted on the association between the frequency of caffeinated beverages consumption and sleep quality.
Results:
The most frequently consumed beverages were unsweetened coffee (22.8%) and the most common time for caffeine was between 12 pm to 5 pm (58.2%). The average sleep quality score based on the PSQI-K was 6.0±2.0 overall, 5.3±1.6 in Q1, and 6.6±2.2 in Q4 (frequent caffeinated beverage drinkers), indicating poorer sleep quality in Q4 (P=0.022). In Q1, 13.3% rated their sleep quality as ‘very good,’ while in Q4, only 2.5% gave the same rating. Poor sleep quality was significantly associated with the frequency of caffeinated beverages per week (β=0.232, P=0.004) and self-reported stress level (β=0.256, P=0.002).
Conclusions
Frequent consumption of caffeinated beverages appears to be associated with poor sleep quality among urban workers. While reducing caffeine intake may contribute to improvements in sleep quality as a health promoting behavior, this hypothesis requires validation through future studies employing personalized intervention approaches.
4.Retrospective study of cultural biases and their reflections among Korean medical students: a cultural hybridity perspective
Kyung Hye PARK ; Ki-Byung LEE ; HyeRin ROH
Korean Journal of Medical Education 2025;37(1):23-34
Purpose:
Most of studies about racial or ethnic biases among medical students have been conducted in English-speaking developed countries. This study explores the hybridity and transformation of Korean medical students’ biases, arguing that a nation’s identity and culture are constantly in a state of ever-changing hybridity.
Methods:
This research used a qualitative document analysis. The study participants were 600 pre-clinical medical students at two medical colleges in Korea, who enrolled in anti-bias programs and subsequently submitted self-reflection essays. Data collection focused on biases related to race, ethnicity, nationality, and medical practices as doctors. Bhabha’s cultural hybridity concepts guided the coding of the data in order to explore the hybridity and transformation of the students’ biases.
Results:
The students presented cultural biases toward patients and doctors with ambivalence related to a person’s high socioeconomic status and open-mindedness, as well as doctors’ excellence and superiority as Korean authoritative figures. Since the students had ambivalent and complex biases toward patients and doctors, they felt unhomeliness as Korean doctors encountering international patients in Korean clinics. However, after discovering their contradictory assumptions, they transformed their unhomeliness into new hybrid identities. The students’ biases were rarely based on race but instead were based on nationality, specifically national class by national income.
Conclusion
Understanding the changing hybrid nature of identities and culture from a cultural hybridity perspective could help clarify medical students’ complex and changing biases and improve anti-bias education. Korean medical students’ hybridized positions suggest that anti-bias education goes beyond focusing on prestige or racism.
5.Human Understanding is Expected of the Physician: Proposing a Model of Disease Development
Sang-Heum PARK ; Samel PARK ; Jin Young KIM ; Hyeon Ah LEE ; Sang Mi LEE ; Tae Hoon LEE ; Sang Byung BAE ; Sung Hae CHANG ; Si Hyong JANG ; Sung Wan CHUN ; Jong Ho MOON
Korean Journal of Medicine 2025;100(1):44-
7.F‑18 FDG PET/CT Clinical Service Trends in Korea from 2018 to 2022:A National Surveillance Study
Jaesun YOON ; Heejin KIM ; Do Hyun WOO ; Seung Yeop CHAE ; Ji Heui LEE ; Inki LEE ; Ilhan LIM ; Byung Il KIM ; Chang Woon CHOI ; Byung Hyung BYUN
Nuclear Medicine and Molecular Imaging 2025;59(2):117-124
Objectives:
To assess the trends and disparities in the utilization of F-18 fluorodeoxyglucose positron emission tomography/ computed tomography (FDG PET/CT) in Korea between 2018 and 2022, with a focus on disease classification, patient demographics, and regional distribution.
Methods:
This national surveillance retrospective study uses data from the Health Insurance Review and Assessment Service (HIRA) database, which includes all FDG PET/CT examinations conducted in Korea from 2018 to 2022. Disease classifications, cancer types, age groups, gender, and geographic regions were analyzed using descriptive statistics. Utilization rates per 100,000 population were calculated for regional comparisons.
Results:
FDG PET/CT utilization increased by 25.4%, from 174,885 examinations in 2018 to 219,377 in 2022. Older age groups (60 years and above) accounted for the majority of examinations, with males undergoing more examinations than females. Oncology remained the primary indication, with lung, colorectal, and non-Hodgkin lymphoma leading in examination numbers. The number of examinations performed on patients aged 60 and above increased at a higher rate compared to those under 60. Significant geographic disparities were found, with Seoul reporting the highest utilization rate (1,114.3 examinations per 100,000 population), while Gyeongbuk exhibited much lower rate (26.2 examinations per 100,000 population).
Conclusions
This study highlights the growing utilization of FDG PET/CT in Korea, particularly among older adults, with significant gender differences in cancer types. The findings also reveal disparities in FDG PET/CT utilization across regions, indicating varying access to advanced imaging technology.
8.Prevalence and characteristics of impacted teeth in Korean orthodontic patients at ten university dental hospitals
Youn-Kyung CHOI ; Sung-Hun KIM ; Yong-Il KIM ; Seong-Sik KIM ; Soo-Byung PARK ; Dong-Soon CHOI ; Ho-Jin KIM ; Kyung-A KIM ; Mo-Hyeon LEE ; Sung-Hwan CHOI ; Sung-Kwon CHOI ; Kyungmin Clara LEE ; Young-Mi JEON ; Sewoong OH ; Seorin JEONG
The Korean Journal of Orthodontics 2025;55(3):234-241
Objective:
This study aimed to investigate the prevalence and characteristics of impacted teeth (ITs) in orthodontic patients at university dental hospitals in Korea.
Methods:
This study included 14,774 patients who visited the Department of Orthodontics at 10 university dental hospitals in Korea between 2020 and 2022 and underwent orthodontic diagnosis. The prevalence and characteristics of ITs were investigated using orthodontic diagnostic records, radiographs, and diagnostic casts.
Results:
The prevalence of ITs, excluding third molar impaction, in Korean orthodontic patients was 13.6% (n = 2,014).The prevalence of ITs in pediatric orthodontic patients was 24.5% (n = 1,614).Of these patients, 68.2% had one IT, 27.5% had two ITs, 24.3% had bilateral IT, and 75.7% had unilateral IT. The most frequent IT was the maxillary canine (50.1%), followed by the mandibular second molar (11.7%), and maxillary second premolar (9.6%). An abnormal eruption path (46.5%) was the most frequent etiology. Orthodontic traction after surgical exposure (70.6%) was the most frequent treatment option. Among the patients with ITs, 29.8% had other dental anomalies, such as tooth agenesis (8.7%), microdontia (8.0%), and supernumerary teeth (5.1%). Furthermore, 50.8% had complications such as cystic lesions (18.3%), transposition (17.7%), and root resorption (14.8%).Among the patients with maxillary canine impaction, 62.2% had labial maxillary canine impaction and 21.1% had palatal maxillary canine impaction.
Conclusions
The prevalence of ITs in Korean orthodontic patients at university dental hospitals was high, particularly in pediatric orthodontic patients.
9.Force and moment analysis of clear aligners: Impact of material properties and design on premolar rotation
Dong-Woo KIM ; Hyun-Jun LEE ; Ki Beom KIM ; Sung-Hun KIM ; Seong-Sik KIM ; Soo-Byung PARK ; Youn-Kyung CHOI ; Yong-Il KIM
The Korean Journal of Orthodontics 2025;55(3):212-223
Objective:
To quantitatively analyze and compare the forces and moments generated by thermoformed polyethylene terephthalate glycol (PETG) and direct-printed TC-85 clear aligners (CAs), with various margin designs, during premolar rotation.
Methods:
In total, 132 CAs were fabricated and divided into four groups (n = 33 per group). Group C consisted of thermoformed PETG aligners with a 2 mm gingival margin. Group E comprised direct-printed TC-85 aligners with equi-gingival margin, whereas Group G utilized direct-printed TC-85 aligners with 2 mm gingival margins.Finally, Group T featured direct-printed TC-85 aligners with an additional 1 mm thickness at the mesial embrasure. The forces and moments were measured using a 6-axis force/moment transducer at 2°, 3°, and 4° of rotation. All measurements were conducted at 37°C to simulate intraoral conditions. Forces were measured in the buccolingual, anteroposterior, and vertical directions, while moments were measured in the mesiodistal, buccolingual, and rotational planes.
Results:
The PETG aligners (Group C) showed significantly increased buccal and posterior force across the rotation angles (P < 0.05), whereas the intrusive force remained consistent. In contrast, the TC-85 aligners maintained consistent forces across all rotation angles.Direct-printed aligners demonstrated significantly lower intrusive forces than PETG aligners (P < 0.001). Group T exhibited reduced unwanted forces while maintaining effective rotational moments. Furthermore, all direct-printed aligners showed more predictable force delivery patterns than thermoformed aligners.
Conclusions
Direct-printed TC-85 aligners demonstrated superior force consistency and reduced unwanted side effects compared with traditional PETG aligners. Although marginal design modifications did not significantly improve rotational efficiency, they effectively reduced unwanted intrusive forces.
10.Protective effect of maltol on pathological response of cardiomyocyte in dystrophic mice
Ahyoung LEE ; Hayeong KWON ; Seulmin KIM ; Yoonhee JEONG ; Byung Tae CHOI ; Changwon KHO
The Korean Journal of Physiology and Pharmacology 2025;29(2):235-244
Heart diseases are a significant contributor to global morbidity and mortality, and despite their diverse and complex mechanisms, treatment options remain limited. Maltol, a natural compound with antioxidant and anti-inflammatory activities, exhibits potential for addressing this need. This study evaluates the cardioprotective effects of maltol in isoproterenol (ISO)-induced cardiac stress models and Duchenne muscular dystrophy (DMD). Maltol’s cardiac cytotoxicity was assessed in rodent (H9c2) and human (AC16) cells and compared with that of dapagliflozin to illustrate its cardiac safety. In ISO-induced stress models, maltol significantly reduced hypertrophic markers and inflammation while enhancing autophagy and antioxidant pathways. In the mdx mice, a DMD model, maltol treatment improved cardiac contractility and reduced pathogenic remodeling. Enhanced phosphorylation of phospholamban and trends toward higher SERCA2a expression indicated enhanced Ca 2+ handling, which is crucial in DMD cardiomyopathy. This study demonstrated that maltol has the potential to provide therapeutic benefits for DMD and other cardiac conditions characterized by hypertrophy and inflammation, as evidenced by its well-known antioxidant properties, low cytotoxicity, and capacity to enhance cardiac function and Ca 2+ handling.

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