Cardiac organoids have emerged as invaluable tools for assessing the impact of diverse substances on heart function.This report introduces guidelines for general requirements for manufacturing cardiac organoids and conducting cardiac organoid-based assays, encompassing protocols, analytical methodologies, and ethical considerations. In the quest to employ recently developed three-dimensional cardiac organoid models as substitutes for animal testing, it becomes imperative to establish robust criteria for evaluating organoid quality and conducting toxicity assessments. This guideline addresses this need, catering to regulatory requirements, and describes common standards for organoid quality and toxicity assessment methodologies, commensurate with current technological capabilities. While acknowledging the dynamic nature of technological progress and the potential for future comparative studies, this guideline serves as a foundational framework. It offers a comprehensive approach to standardized cardiac organoid testing, ensuring scientific rigor, reproducibility, and ethical integrity in investigations of cardiotoxicity, particularly through the utilization of human pluripotent stem cell-derived cardiac organoids.

PURPOSE: Standardization quality assurance (QA) program of CyberKnife for suitable circumstances in Korea has not been established. In this research, we investigated the development of QA program for CyberKnife and evaluation of the feasibility under applications. MATERIALS AND METHODS: Considering the feature of constitution for systems and the therapeutic methodology of CyberKnife, the list of quality control (QC) was established and divided dependent on the each period of operations. And then all these developed QC lists were categorized into three groups such as basic QC, delivery specific QC, and patient specific QC based on the each purpose of QA. In order to verify the validity of the established QA program, this QC lists was applied to two CyberKnife centers. The acceptable tolerance was based on the undertaking inspection list from the CyberKnife manufacturer and the QC results during last three years of two CyberKnife centers in Korea. The acquired measurement results were evaluated for the analysis of the current QA status and the verification of the propriety for the developed QA program. RESULTS: The current QA status of two CyberKnife centers was evaluated from the accuracy of all measurements in relation with application of the established QA program. Each measurement result was verified having a good agreement within the acceptable tolerance limit of the developed QA program. CONCLUSION: It is considered that the developed QA program in this research could be established the standardization of QC methods for CyberKnife and confirmed the accuracy and stability for the image-guided stereotactic radiotherapy.
Constitution and Bylaws ; Humans ; Korea ; Mortuary Practice ; Quality Control ; Radiotherapy

In this study, we estimated inhomogeneity correction factor in small field. And, we evaluated accuracy of treatment planning and measurement data which applied inhomogeneity correction factor or not. We developed the Inhomogeneity Correction Phantom (ICP) for insertion of inhomogeneity materials. The inhomogeneity materials were 12 types in each different electron density. This phantom is able to adapt the EBT film and 0.125 cc ion chamber for measurement of dose distribution and point dose. We evaluated comparison of planning and measurement data using ICP. When we applied to inhomogeneity correction factor or not, the average difference was 1.63% and 10.05% in each plan and film measurement data. And, the average difference of dose distribution was 10.09% in each measurement film. And the average difference of point dose was 0.43% and 2.09% in each plan and measurement data. In conclusion, if we did not apply the inhomogeneity correction factor in small field, it shows more great difference in measurement data. The planning system using this study shows good result for correction of inhomogeneity materials. In radiosurgery using small field, we should be correct the inhomogeneity correction factor, more exactly.
Electrons ; Radiosurgery

BACKGROUND: This study aimed to estimate the incidence and prevalence of idiopathic inflammatory myopathies (IIM) and associated comorbidities in Korea from 2006 to 2015. METHODS: IIM between 2004 to 2015 were identified using the Korean National Health Insurance Service medical claim database. The case definition required more than one visit based on diagnostic codes including juvenile dermatomyositis (JDM), dermatomyositis (DM), or polymyositis (PM) and registration in the Individual Copayment Beneficiaries Program (ICBP) for rare and intractable diseases. IIM patients with a disease-free period of 24 months before the index date were defined as incident cases. The Elixhauser comorbidity score was calculated. RESULTS: Using the base case definition, 1,150 prevalent patients with IIM (117 JDM, 521 DM, 512 PM) were recorded in 2006 and 2,210 (130 JDM, 1,101 DM, 869 PM) in 2015. The prevalence was estimated at 2.3–4.0 (0.9–1.2 for JDM, 1.2–2.7 for DM, 1.4–2.1 for PM)/100,000 person-year (PY). We identified 218 incident cases of IIM in 2006 (18 JDM, 98 DM, 102 PM) and 191 cases (7 JDM, 83 DM, 101 PM) in 2015. The incidence was estimated at 2.9–5.2 (0.7–1.9 for JDM, 1.8–4.0 for DM, 1.6–3.0 for PM)/1,000,000 PY. The mean age (± standard deviation) of prevalent patients with IIM was 51.2 (± 16.9) years, and the percentage of women was 72.1%. More than two-thirds of patients (70.7%) had more than two comorbidities. Twenty percent of patients had interstitial lung diseases. CONCLUSION: In Korea, the incidence and prevalence of IIM were 2.9–5.2/1,000,000 PY and 2.3–4.0/100,000 PY, respectively.
Comorbidity ; Dermatomyositis ; Female ; Humans ; Incidence ; Korea ; Lung Diseases, Interstitial ; Myositis ; National Health Programs ; Polymyositis ; Prevalence

The aim of this study was to investigate the relationship between obesity, insulin resistance and atherosclerosis in type 2 diabetes mellitus (T2DM) patients. Total 530 patients with T2DM were included. To evaluate the severity of atherosclerosis, we measured the coronary artery calcification (CAC) score, intima-media thickness (IMT) of the common carotid artery, and the ankle-brachial pressure index (ABPI). Subjects were classified according to body mass index (BMI), a marker of general obesity, and waist-to-hip ratio (WHR), a marker of regional obesity. The insulin sensitivity index (ISI) was measured by the short insulin tolerance test. All subjects were classified into four groups, according to BMI: the under-weight group, the normal-weight (NW) group, the over-weight (OW) group, and the obese (OB) group. WHR and systolic blood pressure, triglycerides (TG), HDL-cholesterol (HDLC), free fatty acids (FFA), fibrinogen, and fasting c-peptide levels were significantly different between BMI groups. TG, HDL-C, FFA, fibrinogen and ISI were significantly different between patients with and without abdominal obesity. In the OW group as well as in the NW group, carotid IMT, ABPI and CAC score were significantly different between patients with and without abdominal obesity. This study indicates that abdominal obesity was associated with atherosclerosis in T2DM patients.
Aged ; Atherosclerosis/complications ; Blood Pressure ; Coronary Vessels/pathology ; Diabetes Complications ; Diabetes Mellitus, Type 2/*genetics ; Female ; Humans ; Insulin Resistance ; Korea ; Male ; Middle Aged ; Obesity/*complications/*genetics ; Triglycerides/metabolism ; Tunica Intima/pathology ; Tunica Media/pathology

PURPOSE: Follow-up after primary treatment for breast cancer is an important component of survivor care and various international guidelines exist for the surveillance. However, little is known about current actual practice patterns of physicians whether they adhere to or deviate from recommended guidelines. The aim of this study was to determine how physicians follow-up their patients after primary treatment for breast cancer in Korea. METHODS: A questionnaire survey with 34 questions in 4 categories was e-mailed to the members of Korean Breast Cancer Society from November to December 2013. Respondents were asked how they use follow-up modalities after primary treatment of breast cancer and we compared the survey results with present guidelines. RESULTS: Of the 129 respondents, 123 (95.3%) were breast surgeons. The most important consideration in follow-up was tumor stage. History taking, physical examinations, and mammography were conducted in similar frequency recommended by other guidelines while breast ultrasonography was performed more often. The advanced imaging studies such as CT, MRI, and bone scan, which had been recommended to be conducted only if necessary, were also examined more frequently. Regular screenings for secondary malignancy were performed in 38 respondents (29.5%). Five years later after primary treatment, almost the whole respondents (94.6%) themselves monitored their patients. CONCLUSION: A majority of respondents have been performed more intensive follow-up modalities in comparison with present guidelines and less frequently screenings for secondary malignancy. For optimal follow-up of breast cancer survivors, tailored delivery system should be considered.
Breast ; Breast Neoplasms* ; Surveys and Questionnaires ; Electronic Mail ; Follow-Up Studies* ; Humans ; Korea ; Magnetic Resonance Imaging ; Mammography ; Mass Screening ; Physical Examination ; Survivors* ; Ultrasonography, Mammary ; Surveys and Questionnaires

Primary airway tumors are rare in children and no literature reviewed their characteristics each location. We evaluate the clinical characteristics and outcomes of Korean children with primary airway tumors, from the larynx to bronchi. A retrospective chart review of children with primary tumors of the larynx, trachea, and bronchi at Asan Medical Center from January 2000 to July 2016 was conducted. Nineteen children were diagnosed with primary airway tumors of the larynx (47.4%), trachea (10.5%), and bronchi (42.1%). Median follow-up duration was 2.8 years and there were recurrences in 21.1%. Laryngeal tumors were associated with a younger median age at onset (2 months) and diagnosis (4 months), and most were relatively small (median size = 5.3 mm) and symptomatic. Tracheal and bronchial tumors were found in older children (age at onset and diagnosis > 11 years) and large (> 15.0 mm). Most (75%) patients with bronchial tumors were asymptomatic and all the patients with tracheal tumors were symptomatic. This study suggests that we should consider different the locations in primary airway tumor based on the age at onset and diagnosis, initial symptoms or signs, and size of tumor.
Age of Onset ; Bronchi* ; Child ; Chungcheongnam-do ; Diagnosis ; Follow-Up Studies ; Humans ; Larynx* ; Pediatrics ; Recurrence ; Retrospective Studies ; Trachea*

PURPOSE: Data are lacking on the association between the allergic rhinitis (AR) phenotype and sensitization to specific allergens or bronchial hyperresponsiveness (BHR) in children. We here investigated risk factors and comorbidities, including sensitization to specific allergens and BHR, for the AR phenotype by AR and its Impact on Asthma (ARIA) classification in a general population-based birth cohort study. METHODS: We enrolled 606 children aged 7 years from the Panel Study of Korean Children. The AR phenotype was assigned in accordance with the ARIA classification in children. Skin prick tests and Provocholine provocation test were performed. Risk factors and comorbidities for AR phenotypes were then analyzed. RESULTS: The prevalence of mild and moderate to severe AR in our study cohort was 37.2% and 8.8%, respectively. Recent use of analgesics or antipyretics and current cat ownership were associated with the risk of mild persistent AR. Sensitizations to Dermatophagoides Pteronyssinus (Der p), Japanese hop and cat were associated with moderate to severe persistent AR. Children with moderate to severe AR had a higher risk of current asthma and BHR compared to mild AR cases (adjusted odds ratio [aOR], 5.26; 95% confidence interval [CI], 1.77–15.62). Moderate to severe AR with allergic sensitization was associated with the highest risk of BHR (aOR, 11.77; 95% CI, 3.40–40.74). CONCLUSIONS: Moderate to severe-persistent AR is more closely related to respiratory comorbidities and sensitizations than mild AR. Stratifying the AR phenotype by ARIA classification may assist in disease management.
Allergens ; Analgesics ; Animals ; Antipyretics ; Asian Continental Ancestry Group ; Asthma ; Bronchial Hyperreactivity ; Cats ; Child ; Classification ; Cohort Studies ; Comorbidity ; Dermatophagoides pteronyssinus ; Disease Management ; Humans ; Methacholine Chloride ; Odds Ratio ; Ownership ; Parturition ; Phenotype ; Prevalence ; Rhinitis, Allergic ; Risk Factors ; Skin