1.A Case of Exophytic Pilomatricoma with Perforating Figure
Eunjung PARK ; Jiho PARK ; Min-Soo KIM ; Mihn-Sook JUE
Korean Journal of Dermatology 2020;58(5):344-346
Pilomatricoma, also known as calcifying epithelioma of Malherbe, is a benign adnexal skin tumor arising from hair matrix cells. Clinically, pilomatricoma typically presents as a firm, bluish or red colored, deep-seated nodule with overlying normal skin. Several variants of pilomatricoma have been described including perforating, extruding, bullous, melanocytic, giant, keratoacanthoma-like, exophytic, lymphangiectatic, familial, anetodermic, and multiple. Among these, an extruding variant has been very rarely reported. A 10-year-old girl presented with a 2-month history of a rapid-growing, solitary, firm, skin-colored to pinkish, pedunculated papule with a central crusted perforation on the left cheek. Based on the clinical and histological findings, we made a diagnosis of exophytic pilomatricoma with perforating figure. She had no signs of recurrence of the lesion for 8 months after removal.
2.Comparison of Risk Allele Frequencies of Psoriasis-Associated Single-Nucleotide Polymorphisms in Different Population Groups
Donghoon LEE ; Taehan KOO ; Jiho PARK ; Hyun-Tae SHIN
Annals of Dermatology 2023;35(1):32-37
Background:
The prevalence of psoriasis differs by population, and it appears to be more common among Europeans than in East Asians. Recent genome-wide association studies (GWAS) have identified alleles that increase the risk of psoriasis, and these alleles may present different frequencies in different geographic regions.
Objective:
We aimed to gain insights into the causes of differences in disease frequencies according to populations and the factors affecting prevalence and pattern differences.
Methods:
We collected a total of 147 psoriasis-associated single-nucleotide polymorphisms (SNPs) from the GWAS catalog and compared the allele frequency differences in 27 populations using public population frequency in the 1000 Genomes Project phase 3 (n=2,504) and the Korean Reference Genome Database (n=1,722). Additionally, we calculated the composited genetic risk scores across the population groups.
Results:
There were distinct patterns of allele frequencies in different population groups.In many cases, East Asians exhibited allele frequencies opposite to that of Europeans. The genetic risk score was higher in Europeans (average: 0.487) and Americans (average: 0.492) than in East Asians (average: 0.471). The prevalence of psoriasis correlated with the average genetic risk score of the population.
Conclusion
We observed a difference in the allele frequencies of psoriasis-associated SNPs between the studied populations. This result suggests that the difference in the prevalence of psoriasis between population groups can be interpreted to some extent by the genotype.
3.Lichen Planus Developed During the Treatment with Nivolumab in a Patient with Lung Cancer: A Case Report and Literature Review
Eunjung PARK ; Taehan KOO ; Mingyul JO ; Jisook YOO ; Jiho PARK
Korean Journal of Dermatology 2019;57(9):551-555
Nivolumab is a fully-humanized IgG4 monoclonal antibody that competitively binds to the programmed cell death receptor-1 protein (an immune check-point molecule) present on activated T cells. Nivolumab is approved for the treatment of advanced melanoma, lung cancer, and renal cell carcinoma. It attenuates the inactivation of cytotoxic CD8+ T cells and, produces an antitumor effect; however it may be associated with immune-related adverse events, including the development of lichen planus (LP). A 72-year-old man presented with a 2-month history of multiple, polygonal, purplish papules on the dorsal aspect of both hands. He was diagnosed with large cell neuroendocrine carcinoma (LCNEC) of the lung 4 years earlier and was treated with nivolumab (3 mg/kg every 2 weeks) for 9 months. By the 14th course of nivolumab therapy, the patient developed multiple rashes on the dorsal aspect of both hands, and biopsy was consistent with findings of LP. We report a rare case of LP in a patient with lung cancer treated with nivolumab.
Aged
;
Biopsy
;
Carcinoma, Neuroendocrine
;
Carcinoma, Renal Cell
;
Cell Death
;
Exanthema
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Hand
;
Humans
;
Immunoglobulin G
;
Lichen Planus
;
Lichens
;
Lung Neoplasms
;
Lung
;
Melanoma
;
T-Lymphocytes
4.Prediction of Unilateral Vocal Cord Paralysis Patients Through Machine Learning Analysis of Acoustic Parameters: A Preliminary Study
Seungtae KANG ; Su Na PARK ; Ji-Wan HA ; Ki-Su PARK ; Jiho LEE ; Janghyeok YOON ; Gil-Jin JANG ; GilJoon LEE
Journal of the Korean Society of Laryngology Phoniatrics and Logopedics 2024;35(1):24-29
Background and Objectives:
The purpose of this study is to evaluate value of diagnostic tool for vocal cord palsy utilizing artificial intelligence without laryngoscopeMaterials and Method A dataset consisting of recordings from patients with unilateral vocal cord paralysis (n=54) as well as normal individuals (n=163). The dataset included prolonged pronunciations of the vowels /ah/, /u/, /i/, and vocal cord data from paralyzed patients. Various acoustic parameters such as Mel-frequency cepstral coefficients, jitter, shimmer, harmonics-to-noise ratio, and fundamental frequency statistics were analyzed. The classification of vocal cord paralysis encompassed paralysis status, paralysis degree, and paralysis location. The deep learning model employed the leave-one-out method, and the feature set with the highest performance was selected using the following methods.
Results:
Vocal Cord Paralysis Classifier: The classifier accurately distinguished normal voice from vocal cord paralysis, achieving an accuracy and F1 score of 1.0. Paralysis Location Classifier: The classifier accurately differentiated between median and paramedian vocal cord paralysis, achieving an accuracy and micro F1 score of 1.0. Breathiness Degree Classifier: The classifier achieved an accuracy of 0.795 and a mean absolute error of 0.2857 in distinguishing different degrees of breathiness.
Conclusion
Although the small sample size raises concerns of potential overfitting, this preliminary study highlights distinctive acoustic features in cases of unilateral vocal fold paralysis compared to those of normal individuals. These findings suggest the feasibility of determining the presence, degree, and location of paralysis through the utilization of acoustic parameters. Further research is warranted to validate and expand upon these results.
5.Detection of Cervical Foraminal Stenosis from Oblique Radiograph Using Convolutional Neural Network Algorithm
Jihie KIM ; Jae Jun YANG ; Jaeha SONG ; SeongWoon JO ; YoungHoon KIM ; Jiho PARK ; Jin Bog LEE ; Gun Woo LEE ; Sehan PARK
Yonsei Medical Journal 2024;65(7):389-396
Purpose:
This study was conducted to develop a convolutional neural network (CNN) algorithm that can diagnose cervical foraminal stenosis using oblique radiographs and evaluate its accuracy.
Materials and Methods:
A total of 997 patients who underwent cervical MRI and cervical oblique radiographs within a 3-month interval were included. Oblique radiographs were labeled as “foraminal stenosis” or “no foraminal stenosis” according to whether foraminal stenosis was present in the C2–T1 levels based on MRI evaluation as ground truth. The CNN model involved data augmentation, image preprocessing, and transfer learning using DenseNet161. Visualization of the location of the CNN model was performed using gradient-weight class activation mapping (Grad-CAM).
Results:
The area under the curve (AUC) of the receiver operating characteristic curve based on DenseNet161 was 0.889 (95% confidence interval, 0.851–0.927). The F1 score, accuracy, precision, and recall were 88.5%, 84.6%, 88.1%, and 88.5%, respectively.The accuracy of the proposed CNN model was significantly higher than that of two orthopedic surgeons (64.0%, p<0.001; 58.0%, p<0.001). Grad-CAM analysis demonstrated that the CNN model most frequently focused on the foramen location for the determination of foraminal stenosis, although disc space was also frequently taken into consideration.
Conclusion
A CNN algorithm that can detect neural foraminal stenosis in cervical oblique radiographs was developed. The AUC, F1 score, and accuracy were 0.889, 88.5%, and 84.6%, respectively. With the current CNN model, cervical oblique radiography could be a more effective screening tool for neural foraminal stenosis.
6.Analysis of lysosomal membrane proteins exposed to melanin in HeLa cells.
Seung Hyuck BANG ; Dong Jun PARK ; Yang Hoon KIM ; Jiho MIN
Environmental Health and Toxicology 2016;31(1):e2016009-
OBJECTIVES: There have been developed to use targeting ability for antimicrobial, anticancerous, gene therapy and cosmetics through analysis of various membrane proteins isolated from cell organelles. METHODS: It was examined about the lysosomal membrane protein extracted from lysosome isolated from HeLa cell treated by 100 ppm melanin for 24 hours in order to find associated with targeting ability to melanin using by 2-dimensional electrophoresis. RESULTS: The result showed 14 up-regulated (1.5-fold) and 13 down-regulated (2.0-fold) spots in relation to melanin exposure. CONCLUSIONS: It has been found that lysosomal membrane proteins are associated with melanin to decolorize and quantity through cellular activation of lysosome.
Electrophoresis
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Genetic Therapy
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HeLa Cells*
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Humans
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Lysosome-Associated Membrane Glycoproteins*
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Lysosomes
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Melanins*
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Membrane Proteins
;
Organelles
7.Development of a Method to Measure the Radiation Isocenter Size of Linear Accelerators and Quantitative Analysis of the Radiation Isocenter Size for Clinac 21EX Linear Accelerator.
Hosang JEON ; Jiho NAM ; Dahl PARK ; Yong Ho KIM ; Wontaek KIM ; Dongwon KIM ; Yongkan KI ; Donghyun KIM
Korean Journal of Medical Physics 2011;22(3):131-139
A method to get a size of the radiation isocenter of linear accelerators using star-shot images was presented and a computer program was developed to automate the method. Accuracy of the method was verified. The developed program was used to measure sizes of the radiation isocenters for a Clinac 21EX (Varian, USA) using data of quality assurance (QA) performed from June 2008 to December 2010. To calculated the size of radiation isocenter, positions of two points on each central ray of the star-shot image were found and the equation of the central ray was determined using the positions of two points. Using the equations of central rays the radius of the minimum circle intersecting all the central rays, which is one half of the size of radiation isocenter, was calculated. The program measured X-intercepts and y-intercepts of the central rays within errors of 0.084 mm and sizes of radiation isocenters within 0.053 mm. All the errors were less than the spatial resolution of star-shot images 0.085 mm. The radiation isocenter sizes of Clinac 21EX were 0.33+/-0.27 mm, 0.71+/-0.36 mm, 0.50+/-0.16 mm for collimator, gantry and couch respectively. During the measurement period all the measured sizes were less than 2.0 mm and within tolerance. The developed program could calculate the size of radiation isocenters and it would be helpful to routine QA.
Particle Accelerators
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Radius
;
Software
8.Endometriosis of the appendix.
Jiho YOON ; Yong Sang LEE ; Hang Seok CHANG ; Cheong Soo PARK
Annals of Surgical Treatment and Research 2014;87(3):144-147
PURPOSE: Endometriosis is defined as functioning endometrial tissue outside of the uterus. Endometriosis of the appendix is uncommon. Its clinical presentation varies from asymptomatic to acute abdominal pain. The aims of this study were to describe our experience of managing patients with appendiceal endometriosis and to review the clinical characteristics of this medical condition. METHODS: Five cases of appendiceal endometriosis diagnosed between January 2007 and December 2012 were retrospectively reviewed. Patients treated for intra-abdominal endometriosis were excluded. RESULTS: The mean age at diagnosis was 33.8 years old. One patient was in the second trimester of pregnancy. Two patients were asymptomatic. Three patients had clinical symptoms including two with acute pain in the right lower quadrant and one with abdominal discomfort. Four patients showed appendiceal abnormalities in imaging studies including two cases of suspected mucocele and two cases of appendiceal infection. There were no suspicions of endometriosis of the appendix based on preoperative imaging studies. Three patients underwent appendectomy due to clinical symptoms, and two underwent incidental appendectomy combined with another operation. None of the patients received adjuvant therapy. CONCLUSION: Appendiceal endometriosis should be included in the differential diagnosis for acute abdominal pain, especially when women of childbearing age present with clinical symptoms of acute appendicitis.
Abdomen, Acute
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Abdominal Pain
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Acute Pain
;
Appendectomy
;
Appendicitis
;
Appendix*
;
Diagnosis
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Diagnosis, Differential
;
Endometriosis*
;
Female
;
Humans
;
Mucocele
;
Pregnancy
;
Pregnancy Trimester, Second
;
Retrospective Studies
;
Uterus
9.Prognostic value of the maximum standardized uptake value for the locoregional control in early glottic cancer
Donghyun KIM ; Yongkan KI ; Jihyeon JOO ; Hosang JEON ; Dahl PARK ; Jiho NAM ; Wontaek KIM
Radiation Oncology Journal 2021;39(4):297-303
Purpose:
To evaluate the prognostic value of the pretreatment maximum standardized uptake value (SUVmax) for locoregional control (LRC) of early glottic cancer treated with primary radiotherapy.
Materials and Methods:
We retrospectively reviewed the medical records of 101 patients with T1-T2N0 glottic cancer treated with helical tomotherapy between 2013 and 2016. The clinical T-stages were T1 in 87 (86.1%) and T2 in 14 (13.9%) patients. The median total dose was 63 Gy (63–67.5 Gy) in 2.25 Gy per fraction. The survival outcomes were plotted using Kaplan-Meier curves. Receiver operating characteristic curves were used to assess the optimal SUVmax cut-off value for predicting locoregional recurrence.
Results:
The median follow-up period was 58 months (range, 11 to 90 months). The 5-year overall survival (OS) and locoregional recurrence-free survival rates were 96.8% and 85.4%, respectively. The median pretreatment SUVmax of the primary tumor for all 101 patients was 2.3 (range, 1.1 to 9.1). The best cut-off value for SUVmax for predicting LRC was 3.3, with a sensitivity of 78.6% and specificity of 73.6%. Univariate analysis showed that T-stage, overall treatment time (≥43 days), and high SUVmax (≥3.3) were significant predictors of LRC. Multivariate analysis showed that LRC was independently affected by a high SUVmax (≥3.3) (hazard ratio = 5.505, p = 0.020).
Conclusion
High pretreatment SUVmax (≥3.3) is a negative prognostic factor for LRC in early glottic cancer patients treated with primary radiotherapy.
10.Analysis of risk factors for disease progression after salvage radiation therapy with androgen deprivation therapy in prostate cancer patients who have prostate-specific antigen persistence after radical prostatectomy
Kyeonghyo LEE ; Dongchan KIM ; Jiho NAM ; Dahl PARK ; Wontaek KIM ; Jihyeon JOO ; Hosang JEON ; Yongkan KI ; Donghyun KIM
Radiation Oncology Journal 2024;42(2):124-129
Purpose:
To assess risk factors of disease progression after salvage radiation therapy (SRT) with androgen deprivation therapy (ADT) in case of prostate-specific antigen (PSA) persistence after radical prostatectomy (RP).
Materials and Methods:
We analyzed 57 patients who received SRT with ADT between 2013 and 2019 due to PSA persistence after RP. The endpoint was disease progression defined by biochemical recurrence or clinical recurrence. Age, Pre-RP PSA level, Gleason score, pathologic stage, presence of pelvic lymph node dissection, surgical margins, and PSA at 6-8 weeks after RP were analyzed as predictive factors for disease progression. Kaplan-Meier method and Cox regression models were used for data analysis.
Results:
At a median follow-up of 38 months (interquartile range, 26–61), 17 patients had disease progression. Pathologic T stage (pT3b vs. pT3a or lower; hazard ratio [HR] = 9.20; p = 0.035) and PSA level at 6-8 weeks after RP (≥2.04 vs. <2.04 ng/mL; HR = 5.85; p = 0.002) were predictors of disease progression. The 5-year disease progression-free survival rate was 46.7% in pT3b group as compared to 92.9 % in pT3a or lower group, and 18.4% for PSA ≥2.04 ng/mL after RP as compared to 79.2% for PSA <2.04 ng/mL.
Conclusion
Pathological T stage (pT3b) and post RP PSA ≥2.04 ng/mL are independent risk factors of disease progression after SRT with ADT in patients with PSA persistence after RP.