1.Dental Age Estimation in Children Using Convolution Neural Network Algorithm: A Pilot Study
Byung-Yoon ROH ; Hyun-Jeong PARK ; Kyung-Ryoul KIM ; In-Soo SEO ; Yeon-Ho OH ; Ju-Heon LEE ; Chang-Un CHOI ; Yo-Seob SEO ; Ji-Won RYU ; Jong-Mo AHN
Journal of Oral Medicine and Pain 2024;49(4):118-123
		                        		
		                        			 Purpose:
		                        			Recently, deep learning techniques have been introduced for age estimation, with automated methods based on radiographic analysis demonstrating high accuracy. In this study, we applied convolutional neural network (CNN) techniques to the lower dentition area on orthopantomograms (OPGs) of children to develop an automated age estimation model and evaluate its accuracy for use in forensic dentistry. 
		                        		
		                        			Methods:
		                        			In this study, OPGs of 2,856 subjects aged 3-14 years were analyzed. The You Only Look Once (YOLO) V8 object detection technique was applied to extract the mandibular dentition area on OPGs, designating it as the region of interest (ROI). First, 200 radiographs were randomly selected, and were used to train a model for extracting the ROI. The trained model was then applied to the entire dataset. For the CNN image classification task, 80% of OPGs were allocated to the training set, while the remaining 20% were used as the test set. A transfer learning approach was employed using the ResNet50 and VGG19 backbone models, with an ensemble technique combining these models to improve performance. The mean absolute error (MAE) on the test set was used as the validation metric, and the model with the lowest MAE was selected. 
		                        		
		                        			Results:
		                        			In this study, the age estimation model developed using mandibular dentition region from OPGs achieved MAE and root mean squared error (RMSE) values of 0.501 and 0.742, respectively, on the test set, and MAE and RMSE values of 0.273 and 0.354, respectively, on the training set. 
		                        		
		                        			Conclusions
		                        			The automated age estimation model developed in this study demonstrated accuracy comparable to that of previous research and shows potential for applications in forensic investigations. Increasing the sample size and incorporating diverse deep learning techniques are expected to further enhance the accuracy of future age estimation models. 
		                        		
		                        		
		                        		
		                        	
2.Contribution of Enhanced Locoregional Control to Improved Overall Survival with Consolidative Durvalumab after Concurrent Chemoradiotherapy in Locally Advanced Non–Small Cell Lung Cancer: Insights from Real-World Data
Jeong Yun JANG ; Si Yeol SONG ; Young Seob SHIN ; Ha Un KIM ; Eun Kyung CHOI ; Sang-We KIM ; Jae Cheol LEE ; Dae Ho LEE ; Chang-Min CHOI ; Shinkyo YOON ; Su Ssan KIM
Cancer Research and Treatment 2024;56(3):785-794
		                        		
		                        			 Purpose:
		                        			This study aimed to assess the real-world clinical outcomes of consolidative durvalumab in patients with unresectable locally advanced non–small cell lung cancer (LA-NSCLC) and to explore the role of radiotherapy in the era of immunotherapy. 
		                        		
		                        			Materials and Methods:
		                        			This retrospective study assessed 171 patients with unresectable LA-NSCLC who underwent concurrent chemoradiotherapy (CCRT) with or without consolidative durvalumab at Asan Medical Center between May 2018 and May 2021. Primary outcomes included freedom from locoregional failure (FFLRF), distant metastasis-free survival (DMFS), progression-free survival (PFS), and overall survival (OS). 
		                        		
		                        			Results:
		                        			Durvalumab following CCRT demonstrated a prolonged median PFS of 20.9 months (p=0.048) and a 3-year FFLRF rate of 57.3% (p=0.008), compared to 13.7 months and 38.8%, respectively, with CCRT alone. Furthermore, the incidence of in-field recurrence was significantly greater in the CCRT-alone group compared to the durvalumab group (26.8% vs. 12.4%, p=0.027). While median OS was not reached with durvalumab, it was 35.4 months in patients receiving CCRT alone (p=0.010). Patients positive for programmed cell death ligand 1 (PD-L1) expression showed notably better outcomes, including FFLRF, DMFS, PFS, and OS. Adherence to PACIFIC trial eligibility criteria identified 100 patients (58.5%) as ineligible. The use of durvalumab demonstrated better survival regardless of eligibility criteria. 
		                        		
		                        			Conclusion
		                        			The use of durvalumab consolidation following CCRT significantly enhanced locoregional control and OS in patients with unresectable LA-NSCLC, especially in those with PD-L1–positive tumors, thereby validating the role of durvalumab in standard care. 
		                        		
		                        		
		                        		
		                        	
3.Injury patterns in cyclists with alcohol consumption
Da Un JEONG ; Won Cul CHA ; Hee YOON ; Sung Yeon HWANG ; Tae Gun SHIN ; Min Seob SIM ; Ik Joon JO ; Taerim KIM
Journal of the Korean Society of Emergency Medicine 2021;32(2):112-119
		                        		
		                        			Objective:
		                        			As the cycling population grows, the lack of public awareness about the dangers of cycling while under the influence of alcohol is a signifant problem. The purpose of this study was to investigate the association between alcohol consumption and bicycle-related injuries such as traumatic brain injuries (TBI) and excess mortality ratio-adjusted injury severity score (EMR-ISS). 
		                        		
		                        			Methods:
		                        			We conducted a retrospective analysis using data collected from the Korean Emergency Department-based Injury In-depth Surveillance (EDIIS) database from 20 emergency departments during the period 2011-2016. The study subjects who had sustained bicycle-related injuries were over 18 years of age. The covariates included the mechanism, place, and time of injury. The outcomes were TBI incidence and severe and critical injury of EMR-ISS≥25. The effects of alcohol consumption on these outcomes were analyzed, and the variations in effects were determined using logistic regression. 
		                        		
		                        			Results:
		                        			Of the 24,297 individuals studied, 1,912 had alcohol-related bicycle injuries, which led to a higher proportion of single-vehicle injury incidents (alcohol 63.7% vs. non-alcohol 46.4%, P<0.001). The alcohol group had a higher rate of TBI (alcohol 11.5% vs. non-alcohol 4.6%, P<0.001) and severe and critical injury of EMR-ISS (alcohol 23.1% vs. nonalcohol 11.7%, P<0.001). TBI (odds ratio [OR], 2.72; 95% confidence interval [CI], 2.33-3.16) and severe and critical injury of EMR-ISS (OR, 2.26; 95% CI, 2.01-2.53) showed a significant association with alcohol. 
		                        		
		                        			Conclusion
		                        			Our study showed an association of alcohol consumption with a higher incidence of TBI and severe and critical EMR-ISS. Education should focus more on the association between cycling under alcohol influence and injury severity.
		                        		
		                        		
		                        		
		                        	
4.Injury patterns in cyclists with alcohol consumption
Da Un JEONG ; Won Cul CHA ; Hee YOON ; Sung Yeon HWANG ; Tae Gun SHIN ; Min Seob SIM ; Ik Joon JO ; Taerim KIM
Journal of the Korean Society of Emergency Medicine 2021;32(2):112-119
		                        		
		                        			Objective:
		                        			As the cycling population grows, the lack of public awareness about the dangers of cycling while under the influence of alcohol is a signifant problem. The purpose of this study was to investigate the association between alcohol consumption and bicycle-related injuries such as traumatic brain injuries (TBI) and excess mortality ratio-adjusted injury severity score (EMR-ISS). 
		                        		
		                        			Methods:
		                        			We conducted a retrospective analysis using data collected from the Korean Emergency Department-based Injury In-depth Surveillance (EDIIS) database from 20 emergency departments during the period 2011-2016. The study subjects who had sustained bicycle-related injuries were over 18 years of age. The covariates included the mechanism, place, and time of injury. The outcomes were TBI incidence and severe and critical injury of EMR-ISS≥25. The effects of alcohol consumption on these outcomes were analyzed, and the variations in effects were determined using logistic regression. 
		                        		
		                        			Results:
		                        			Of the 24,297 individuals studied, 1,912 had alcohol-related bicycle injuries, which led to a higher proportion of single-vehicle injury incidents (alcohol 63.7% vs. non-alcohol 46.4%, P<0.001). The alcohol group had a higher rate of TBI (alcohol 11.5% vs. non-alcohol 4.6%, P<0.001) and severe and critical injury of EMR-ISS (alcohol 23.1% vs. nonalcohol 11.7%, P<0.001). TBI (odds ratio [OR], 2.72; 95% confidence interval [CI], 2.33-3.16) and severe and critical injury of EMR-ISS (OR, 2.26; 95% CI, 2.01-2.53) showed a significant association with alcohol. 
		                        		
		                        			Conclusion
		                        			Our study showed an association of alcohol consumption with a higher incidence of TBI and severe and critical EMR-ISS. Education should focus more on the association between cycling under alcohol influence and injury severity.
		                        		
		                        		
		                        		
		                        	
5.Serotype Distribution and Antimicrobial Resistance of Invasive and Noninvasive Streptococcus pneumoniae Isolates in Korea between 2014 and 2016
Dong Chul PARK ; Si Hyun KIM ; Dongeun YONG ; In Bum SUH ; Young Ree KIM ; Jongyoun YI ; Wonkeun SONG ; Sae Am SONG ; Hee Won MOON ; Hae Kyung LEE ; Kyoung Un PARK ; Sunjoo KIM ; Seok Hoon JEONG ; Jaehyeon LEE ; Joseph JEONG ; Yu Kyung KIM ; Miae LEE ; Jihyun CHO ; Jong Wan KIM ; Kyeong Seob SHIN ; Sang Hyun HWANG ; Jae Woo CHUNG ; Hye In WOO ; Chae Hoon LEE ; Namhee RYOO ; Chulhun L CHANG ; Hyun Soo KIM ; Jayoung KIM ; Jong Hee SHIN ; Soo Hyun KIM ; Mi Kyung LEE ; Seong Gyu LEE ; Sook Jin JANG ; Kyutaeg LEE ; HunSuk SUH ; Yong Hak SOHN ; Min Jung KWON ; Hee Joo LEE ; Ki Ho HONG ; Kwang Sook WOO ; Chul Min PARK ; Jeong Hwan SHIN
Annals of Laboratory Medicine 2019;39(6):537-544
		                        		
		                        			
		                        			BACKGROUND: Several factors contribute to differences in Streptococcus pneumoniae serotype distribution. We investigated the serotype distribution and antimicrobial resistance of S. pneumoniae isolated between 2014 and 2016 in Korea. METHODS: We collected a total of 1,855 S. pneumoniae isolates from 44 hospitals between May 2014 and May 2016, and analyzed the serotypes by sequential multiplex PCR. We investigated the distribution of each serotype by patient age, source of the clinical specimen, and antimicrobial resistance pattern. RESULTS: The most common serotypes were 11A (10.1%), followed by 19A (8.8%), 3 (8.5%), 34 (8.1%), 23A (7.3%), and 35B (6.2%). The major invasive serotypes were 3 (12.6%), 19A (7.8%), 34 (7.8%), 10A (6.8%), and 11A (6.8%). Serotypes 10A, 15B, 19A, and 12F were more common in patients ≤5 years old, while serotype 3 was more common in patients ≥65 years old compared with the other age groups. The coverage rates of pneumococcal conjugate vaccine (PCV)7, PCV10, PCV13, and pneumococcal polysaccharide vaccine 23 were 11.8%, 12.12%, 33.3%, and 53.6%, respectively. Of the 1,855 isolates, 857 (46.2%) were multi-drug resistant (MDR), with serotypes 11A and 19A predominant among the MDR strains. The resistance rates against penicillin, cefotaxime, and levofloxacin were 22.8%, 12.5%, and 9.4%, respectively. CONCLUSIONS: There were significant changes in the major S. pneumoniae serotypes in the community. Non-PCV13 serotypes increased in patients ≤5 years old following the introduction of national immunization programs with the 10- and 13-polyvalent vaccines.
		                        		
		                        		
		                        		
		                        			Cefotaxime
		                        			;
		                        		
		                        			Humans
		                        			;
		                        		
		                        			Immunization Programs
		                        			;
		                        		
		                        			Korea
		                        			;
		                        		
		                        			Levofloxacin
		                        			;
		                        		
		                        			Multiplex Polymerase Chain Reaction
		                        			;
		                        		
		                        			Penicillins
		                        			;
		                        		
		                        			Pneumococcal Vaccines
		                        			;
		                        		
		                        			Pneumonia
		                        			;
		                        		
		                        			Serogroup
		                        			;
		                        		
		                        			Streptococcus pneumoniae
		                        			;
		                        		
		                        			Streptococcus
		                        			;
		                        		
		                        			Vaccines
		                        			
		                        		
		                        	
6.Radiocarbon Dating of Skeletal Remains: Case Report
Jong Pil PARK ; Seung Gyu CHOI ; Sang Seob LEE ; Won Joon LEE ; Jeong Uk SEO ; Chang Un CHOI ; Yi Suk KIM ; U Young LEE ; Minsung CHOI ; Kyung Moo YANG
Korean Journal of Legal Medicine 2018;42(3):105-109
		                        		
		                        			
		                        			 While radioactive isotope analysis has proved to be a useful method in disciplines such as archaeology and forensic anthropology, more recently, radiocarbon dating has allowed for a more nuanced biological profile of human skeletal remains. Radiocarbon dating has been made possible by the above ground nuclear bomb test conducted in 1963, which raised the level of atmospheric radiocarbon concentration to almost twice the natural level. Because the annually measured tropospheric ¹â´C concentrations are integrated into the bomb peak curve, the time of birth and death of an individual can be estimated by comparing the radiocarbon content of a skeletal sample to the bomb-curve value. In July 2017, about 1,000 skeletal remains were excavated at the construction site of Sokcho. For medico-legal purposes, we conducted anthropological and odontological examinations of all the human remains. We then conducted the radiocarbon analysis on seven femora (head and body portions), five mandibular teeth, and soil from the site through a request to the Korea Institute of Geoscience and Mineral Resources. The results demonstrated that the estimated year of birth or death was prior to the 1950s. Due to the diverse distribution of results, we deduced that the human remains were from the local mass grave. This study supports and suggests the use of radiocarbon dating more frequently in the analysis of human skeletal remains. 
		                        		
		                        		
		                        		
		                        	
7.The Application of Paewinsky et al.'s Age Estimation Method to Periapical Radiographs
Byung Yoon ROH ; Jeong Uk SEO ; Chang Gyum KIM ; Chang Un CHOI ; Won Joon LEE ; Sang Seob LEE
Korean Journal of Legal Medicine 2018;42(4):141-145
		                        		
		                        			
		                        			 There have been many radiographic studies on age estimation that evaluate reduction in size of dental pulp cavity with secondary dentin formation. The Paewinsky method reported high accuracy in estimating ages by measuring the width of the pulp cavity in panoramic radiographs. The aim of this study was to evaluate the application of the Paewinsky method to digital periapical radiographs. This study was conducted on 103 cases that reported to the Section of Human Identification of the National Forensic Service. The age was calculated by applying the Paewinsky method that measures the root and pulp canal width at three points in a tooth. The estimation results were compared with those calculated by the Johanson method. When the Paewinsky models were applied to digital periapical radiographs, the errors were significantly greater as compared to the original study. The errors of the maxillary second premolar and mandibular lateral incisor were greater than those of the maxillary central incisor, lateral incisor, mandibular canine, and first premolar. Furthermore, errors of the age estimation models in level C were greater than those in levels A and B. This study could be a reference for the application of the Paewinsky method to digital periapical radiographs. 
		                        		
		                        		
		                        		
		                        	
8.Radiocarbon Dating of Skeletal Remains: Case Report
Jong Pil PARK ; Seung Gyu CHOI ; Sang Seob LEE ; Won Joon LEE ; Jeong Uk SEO ; Chang Un CHOI ; Yi Suk KIM ; U Young LEE ; Minsung CHOI ; Kyung Moo YANG
Korean Journal of Legal Medicine 2018;42(3):105-109
		                        		
		                        			
		                        			While radioactive isotope analysis has proved to be a useful method in disciplines such as archaeology and forensic anthropology, more recently, radiocarbon dating has allowed for a more nuanced biological profile of human skeletal remains. Radiocarbon dating has been made possible by the above ground nuclear bomb test conducted in 1963, which raised the level of atmospheric radiocarbon concentration to almost twice the natural level. Because the annually measured tropospheric ¹⁴C concentrations are integrated into the bomb peak curve, the time of birth and death of an individual can be estimated by comparing the radiocarbon content of a skeletal sample to the bomb-curve value. In July 2017, about 1,000 skeletal remains were excavated at the construction site of Sokcho. For medico-legal purposes, we conducted anthropological and odontological examinations of all the human remains. We then conducted the radiocarbon analysis on seven femora (head and body portions), five mandibular teeth, and soil from the site through a request to the Korea Institute of Geoscience and Mineral Resources. The results demonstrated that the estimated year of birth or death was prior to the 1950s. Due to the diverse distribution of results, we deduced that the human remains were from the local mass grave. This study supports and suggests the use of radiocarbon dating more frequently in the analysis of human skeletal remains.
		                        		
		                        		
		                        		
		                        			Archaeology
		                        			;
		                        		
		                        			Bombs
		                        			;
		                        		
		                        			Earth Sciences
		                        			;
		                        		
		                        			Forensic Anthropology
		                        			;
		                        		
		                        			Gangwon-do
		                        			;
		                        		
		                        			Humans
		                        			;
		                        		
		                        			Korea
		                        			;
		                        		
		                        			Methods
		                        			;
		                        		
		                        			Miners
		                        			;
		                        		
		                        			Parturition
		                        			;
		                        		
		                        			Radiometric Dating
		                        			;
		                        		
		                        			Soil
		                        			;
		                        		
		                        			Tooth
		                        			
		                        		
		                        	
9.The Application of Paewinsky et al.'s Age Estimation Method to Periapical Radiographs
Byung Yoon ROH ; Jeong Uk SEO ; Chang Gyum KIM ; Chang Un CHOI ; Won Joon LEE ; Sang Seob LEE
Korean Journal of Legal Medicine 2018;42(4):141-145
		                        		
		                        			
		                        			There have been many radiographic studies on age estimation that evaluate reduction in size of dental pulp cavity with secondary dentin formation. The Paewinsky method reported high accuracy in estimating ages by measuring the width of the pulp cavity in panoramic radiographs. The aim of this study was to evaluate the application of the Paewinsky method to digital periapical radiographs. This study was conducted on 103 cases that reported to the Section of Human Identification of the National Forensic Service. The age was calculated by applying the Paewinsky method that measures the root and pulp canal width at three points in a tooth. The estimation results were compared with those calculated by the Johanson method. When the Paewinsky models were applied to digital periapical radiographs, the errors were significantly greater as compared to the original study. The errors of the maxillary second premolar and mandibular lateral incisor were greater than those of the maxillary central incisor, lateral incisor, mandibular canine, and first premolar. Furthermore, errors of the age estimation models in level C were greater than those in levels A and B. This study could be a reference for the application of the Paewinsky method to digital periapical radiographs.
		                        		
		                        		
		                        		
		                        			Age Determination by Teeth
		                        			;
		                        		
		                        			Bicuspid
		                        			;
		                        		
		                        			Dental Pulp Cavity
		                        			;
		                        		
		                        			Dentin, Secondary
		                        			;
		                        		
		                        			Forensic Anthropology
		                        			;
		                        		
		                        			Incisor
		                        			;
		                        		
		                        			Methods
		                        			;
		                        		
		                        			Radiography, Dental
		                        			;
		                        		
		                        			Tooth
		                        			
		                        		
		                        	
10.Comparative Effects of Non-Thermal Atmospheric Pressure Plasma on Migration and Invasion in Oral Squamous Cell Cancer, by Gas Type.
Sung Un KANG ; Seong Jin SEO ; Yeon Soo KIM ; Yoo Seob SHIN ; Yoon Woo KOH ; Chang Min LEE ; Sang Sik YANG ; Jong Soo LEE ; Eunpyo MOON ; Hami KANG ; Jeong Beom RYEO ; Yuijina LEE ; Chul Ho KIM
Yonsei Medical Journal 2017;58(2):272-281
		                        		
		                        			
		                        			PURPOSE: The fourth state of matter, plasma is known as an ionized gas with electrons, radicals and ions. The use of non-thermal plasma (NTP) in cancer research became possible because of the progresses in plasma medicine. Previous studies on the potential NTP-mediated cancer therapy have mainly concentrated on cancer cell apoptosis. In the present study, we compared the inhibitory effect of NTP on cell migration and invasion in the oral squamous cancer cell lines. MATERIALS AND METHODS: We used oral squamous cancer cell lines (SCC1483, MSKQLL1) and different gases (N₂, He, and Ar). To investigate the mechanism of plasma treatment, using different gases (N₂, He, and Ar) which induces anti-migration and anti-invasion properties, we performed wound healing assay, invasion assay and gelatin zymography. RESULTS: The results showed that NTP inhibits cancer cell migration and invasion of oral squamous cancer cell. In addition, focal adhesion kinase expression and matrix metalloproteinase-2/9 activity were also inhibited. CONCLUSION: The suppression of cancer cell invasion by NTP varied depending on the type of gas. Comparison of the three gases revealed that N₂ NTP inhibited cell migration and invasion most potently via decreased expression of focal adhesion kinase and matrix metalloproteinase activity.
		                        		
		                        		
		                        		
		                        			Apoptosis
		                        			;
		                        		
		                        			Cell Line
		                        			;
		                        		
		                        			Cell Movement
		                        			;
		                        		
		                        			Epithelial Cells*
		                        			;
		                        		
		                        			Focal Adhesion Protein-Tyrosine Kinases
		                        			;
		                        		
		                        			Gases
		                        			;
		                        		
		                        			Gelatin
		                        			;
		                        		
		                        			Ions
		                        			;
		                        		
		                        			Neoplasms, Squamous Cell*
		                        			;
		                        		
		                        			Paxillin
		                        			;
		                        		
		                        			Plasma
		                        			;
		                        		
		                        			Plasma Gases*
		                        			;
		                        		
		                        			Wound Healing
		                        			
		                        		
		                        	
            
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