1.Surgical Management of Neuropathic Arthropathy due to Rheumatoid Arthritis: A Case Report
Hyunkyu YU ; Jaewon KIM ; Sunghyun LEE
Journal of Korean Foot and Ankle Society 2024;28(3):107-110
Neuropathic arthropathy (Charcot arthropathy) is a progressive joint disease often associated with conditions such as diabetes, leading to severe joint deformity and pain. However, its occurrence in patients with rheumatoid arthritis (RA) is rare and not well documented.This case report describes a 48-year-old woman with a long history of RA who developed a severe deformity of her right ankle, identified as neuropathic arthropathy extending to the subtalar joint (Brodsky classification type 3A). After excluding other potential causes, the condition was determined to be secondary to RA-associated peripheral neuropathy. Surgery, including allograft and autograft fixation, was performed to correct the deformity. Post-operative complications, such as wound infection, were treated with negative pressure wound therapy and skin grafting. At the 18-month follow-up, the patient was able to walk without pain, demonstrating successful joint fusion.
2.Combinatorial Effect of Mesenchymal Stem Cells and Extracellular Vesicles in a Hydrogel on Cartilage Regeneration
Woong Jin CHO ; Jinsung AHN ; Minju LEE ; Hyejong CHOI ; Sunghyun PARK ; Kyung-Yup CHA ; SunJun LEE ; Yoshie ARAI ; Soo-Hong LEE
Tissue Engineering and Regenerative Medicine 2023;20(1):143-154
BACKGROUND:
Mesenchymal stem cells (MSCs) are used for tissue regeneration due to their wide differentiation capacity and anti-inflammatory effects. Extracellular vesicles (EVs) derived from MSCs are also known for their regenerative effects as they contain nucleic acids, proteins, lipids, and cytokines similar to those of parental cells. There are several studies on the use of MSCs or EVs for tissue regeneration. However, the combinatorial effect of human MSCs (hMSCs) and EVs is not clear. In this study, we investigated the combinatorial effect of hMSCs and EVs on cartilage regeneration via co-encapsulation in a hyaluronic-acid (HA)-based hydrogel.
METHODS:
A methacrylic-acid-based HA hydrogel was prepared to encapsulate hMSCs and EVs in hydrogels. Through in vitro and in vivo analyses, we investigated the chondrogenic potential of the HA hydrogel-encapsulated with hMSCs and EVs.
RESULTS:
Co-encapsulation of hMSCs with EVs in the HA hydrogel increased the chondrogenic differentiation of hMSCs and regeneration of damaged cartilage tissue compared with that of the HA hydrogel loaded with hMSCs only.
CONCLUSION
Co-encapsulation of hMSCs and EVs in the HA hydrogel effectively enhances cartilage tissue regeneration due to the combinatorial therapeutic effect of hMSCs and EVs. Thus, in addition to cartilage tissue regeneration for the treatment of osteoarthritis, this approach would be a useful strategy to improve other types of tissue regeneration.
3.Feasibility of artificial intelligence-driven interfractional monitoring of organ changes by mega-voltage computed tomography in intensity-modulated radiotherapy of prostate cancer
Yohan LEE ; Hyun Joon CHOI ; Hyemi KIM ; Sunghyun KIM ; Mi Sun KIM ; Hyejung CHA ; Young Ju EUM ; Hyosung CHO ; Jeong Eun PARK ; Sei Hwan YOU
Radiation Oncology Journal 2023;41(3):186-198
Purpose:
High-dose radiotherapy (RT) for localized prostate cancer requires careful consideration of target position changes and adjacent organs-at-risk (OARs), such as the rectum and bladder. Therefore, daily monitoring of target position and OAR changes is crucial in minimizing interfractional dosimetric uncertainties. For efficient monitoring of the internal condition of patients, we assessed the feasibility of an auto-segmentation of OARs on the daily acquired images, such as megavoltage computed tomography (MVCT), via a commercial artificial intelligence (AI)-based solution in this study.
Materials and Methods:
We collected MVCT images weekly during the entire course of RT for 100 prostate cancer patients treated with the helical TomoTherapy system. Based on the manually contoured body outline, the bladder including prostate area, and rectal balloon regions for the 100 MVCT images, we trained the commercially available fully convolutional (FC)-DenseNet model and tested its auto-contouring performance.
Results:
Based on the optimally determined hyperparameters, the FC-DenseNet model successfully auto-contoured all regions of interest showing high dice similarity coefficient (DSC) over 0.8 and a small mean surface distance (MSD) within 1.43 mm in reference to the manually contoured data. With this well-trained AI model, we have efficiently monitored the patient's internal condition through six MVCT scans, analyzing DSC, MSD, centroid, and volume differences.
Conclusion
We have verified the feasibility of utilizing a commercial AI-based model for auto-segmentation with low-quality daily MVCT images. In the future, we will establish a fast and accurate auto-segmentation and internal organ monitoring system for efficiently determining the time for adaptive replanning.
4.Therapeutic Extracellular Vesicles from Tonsil-Derived Mesenchymal Stem Cells for the Treatment of Retinal Degenerative Disease
Seung Woo CHOI ; Sooin SEO ; Hye Kyoung HONG ; So Jung YOON ; Minah KIM ; Sunghyun MOON ; Joo Yong LEE ; Jaeseung LIM ; Jong Bum LEE ; Se Joon WOO
Tissue Engineering and Regenerative Medicine 2023;20(6):951-964
BACKGROUND:
Retinal degenerative disease (RDD), one of the most common causes of blindness, is predominantly caused by the gradual death of retinal pigment epithelial cells (RPEs) and photoreceptors due to various causes. Cell-based therapies, such as stem cell implantation, have been developed for the treatment of RDD, but potential risks, including teratogenicity and immune reactions, have hampered their clinical application. Stem cell-derived extracellular vesicles (EVs) have recently emerged as a cell-free alternative therapeutic strategy; however, additional invasiveness and low yield of the stem cell extraction process is problematic.
METHODS:
To overcome these limitations, we developed therapeutic EVs for the treatment of RDD which were extracted from tonsil-derived mesenchymal stem cells obtained from human tonsil tissue discarded as medical waste following tonsillectomy (T-MSC EVs). To verify the biocompatibility and cytoprotective effect of T-MSC EVs, we measured cell viability by co-culture with human RPE without or with toxic all-trans-retinal. To elucidate the cytoprotective mechanism of T-MSC EVs, we performed transcriptome sequencing using RNA extracted from RPEs. The in vivo protective effect of T-MSC EVs was evaluated using Pde6b gene knockout rats as an animal model of retinitis pigmentosa.
RESULTS:
T-MSC EVs showed high biocompatibility and the human pigment epithelial cells were significantly protected in the presence of T-MSC EVs from the toxic effect of all-trans-retinal. In addition, T-MSC EVs showed a dosedependent cell death-delaying effect in real-time quantification of cell death. Transcriptome sequencing analysis revealed that the efficient ability of T-MSC EVs to regulate intracellular oxidative stress may be one of the reasons explaining their excellent cytoprotective effect. Additionally, intravitreally injected T-MSC EVs had an inhibitory effect on the destruction of the outer nuclear layer in the Pde6b gene knockout rat.
CONCLUSIONS
Together, the results of this study indicate the preventive and therapeutic effects of T-MSC EVs during the initiation and development of retinal degeneration, which may be a beneficial alternative for the treatment of RDD.
5.Molecular characteristics of ESBLproducing Escherichia coli isolated from chickens with colibacillosis
Journal of Veterinary Science 2022;23(3):e37-
Background:
Avian pathogenic Escherichia coli (APEC) causes colibacillosis, resulting in significant economic losses in the poultry industry.
Objectives:
In this study, the molecular characteristics of two extended-spectrum betalactamase (ESBL)-producing APEC isolates were compared with previously reported ESBLproducing E. coli isolates.
Methods:
The molecular characteristics of E. coli isolates and the genetic environments of the ESBL genes were investigated using whole genome sequencing.
Results:
The two ESBL-producing APEC were classified into the phylogenetic groups C and B1 and ST410 and ST162, respectively. Moreover, the ESBL genes of the two isolates were harbored in different Inc plasmids. The EC1809182 strain, harboring the blaCTX-M-55 gene on the plasmid, exhibited extensive homology to IncFIB (98.4%) and IncFIC(FII) (95.8%). The EC1809191 strain, harboring the blaCTX-M-1 gene, was homologous to IncI1-I (Gamma) (99.3%). All chromosomes carried the multidrug transporter, mdf(A) gene. Mobile genetic elements, adjacent to CTX-M genes, facilitated the dissemination of genes in the two isolates, analogous to other ESBL-producing E. coli isolates.
Conclusions
This study clarifies the transmission dynamics of CTX-M genes and supports strengthened surveillance to prevent the transmission of the antimicrobial-resistant genes to humans via the food chain.
6.Molecular characteristics of Escherichia coli from bulk tank milk in Korea
Journal of Veterinary Science 2022;23(1):e9-
Background:
Escherichia coli, which causes subclinical or clinical mastitis in cattle, is responsible for transmitting antimicrobial resistance via human consumption of raw milk or raw milk products.
Objectives:
The objective of this study was to investigate the molecular characteristics of 183 E. coli from bulk tank milk of five different dairy factories in Korea.
Methods:
The molecular characteristics of E. coli such as serogroup, virulence, antimicrobial resistance, and integron genes were detected using polymerase chain reaction and antimicrobial susceptibility were tested using the disk diffusion test.
Results:
In the distribution of phylogenetic groups, group D was the most prevalent (59.6%) and followed by group B1 (25.1%). The most predominant serogroup was O173 (15.3%), and a total of 46 different serotypes were detected. The virulence gene found most often was fimH (73.2%), and stx1, fimH, incC, fyuA, and iutA genes were significantly higher in isolates of phylogenetic group B1 compared to phylogenetic groups A, B2, and D (p < 0.05). Among 64 E. coli isolates that showed resistance to at least one antimicrobial, the highest resistance rate was observed for tetracyclines (37.5%). All 18 integron-positive E. coli carried the integron class I (int1) gene, and three different gene cassette arrangements, dfrA12+aadA2 (2 isolates), aac(6′)-Ib3+aac(6′)-Ib-cr+aadA4 (2 isolates), and dfrA17+aadA5 (1 isolate) were detected.
Conclusions
These data suggest that the E. coli from bulk tank milk can be an indicator for dissemination of antimicrobial resistance and virulence factors via cross-contamination.
7.Arthroscopic Partial Meniscectomy versus Physical Therapy for Degenerative Meniscal Tear:a Systematic Review
Miyoung CHOI ; Su Jung LEE ; Chan Mi PARK ; Seungeun RYOO ; Sunghyun KIM ; Ju Yeon JANG ; Hyun Ah KIM
Journal of Korean Medical Science 2021;36(45):e292-
Background:
Meniscal tears are commonly observed in patients with knee osteoarthritis (OA), however, clinical significance of such lesions detected by magnetic resonance imaging is in many cases unclear. This study aimed to determine the clinical effectiveness of arthroscopic partial meniscectomy (APM) compared with non-operative care in patients with knee OA.Method: We used existing systematic reviews with updates of latest studies. Three randomized controlled studies were selected, where two studies compared the effects of APM plus physical therapy (PT) with PT alone and one compared APM alone and PT alone. While 1 study exclusively included OA patients, 2 studies included 21.1 and 12% of patients with no radiographic OA. Patients with knee locking were unanimously excluded.
Results:
Upon comparison of APM plus PT and PT alone, there was no significant difference observed in knee function, physical activity, or adverse events. Knee pain was observed to be significantly lower in the APM plus PT group at 6 months, but there was no difference between the two groups at 12 and 24 months. With respect to the comparison between APM alone and PT alone, PT was non-inferior based on the criteria for knee function during 24 months; however, knee pain was significantly reduced in the APM alone group.
Conclusions
Our study showed that knee pain was significantly improved in the APM group compared to non-operative care group at 6 months and over 24 months. Our result was based on only 3 randomized controlled trials (RCTs) revealing a significant knowledge gap, hence demanding more high-quality RCTs in OA patients.
8.Influence of different boost techniques on radiation dose to the left anterior descending coronary artery.
Kawngwoo PARK ; Yongha LEE ; Jihye CHA ; Sei Hwan YOU ; Sunghyun KIM ; Jong Young LEE
Radiation Oncology Journal 2015;33(3):242-249
PURPOSE: The purpose of this study is to compare the dosimetry of electron beam (EB) plans and three-dimensional helical tomotherapy (3DHT) plans for the patients with left-sided breast cancer, who underwent breast conserving surgery. MATERIALS AND METHODS: We selected total of 15 patients based on the location of tumor, as following subsite: subareolar, upper outer, upper inner, lower lateral, and lower medial quadrants. The clinical target volume (CTV) was defined as the area of architectural distortion surrounded by surgical clip plus 1 cm margin. The conformity index (CI), homogeneity index (HI), quality of coverage (QC) and dose-volume parameters for the CTV, and organ at risk (OAR) were calculated. The following treatment techniques were assessed: single conformal EB plans; 3DHT plans with directional block of left anterior descending artery (LAD); and 3DHT plans with complete block of LAD. RESULTS: 3DHT plans, regardless of type of LAD block, showed significantly better CI, HI, and QC for the CTVs, compared with the EB plans. However, 3DHT plans showed increase in the V(1Gy) at skin, left lung, and left breast. In terms of LAD, 3DHT plans with complete block of LAD showed extremely low dose, while dose increase in other OARs were observed, when compared with other plans. EB plans showed the worst conformity at upper outer quadrants of tumor bed site. CONCLUSION: 3DHT plans offer more favorable dose distributions to LAD, as well as improved target coverage in comparison with EB plans.
Arteries
;
Breast
;
Breast Neoplasms
;
Coronary Vessels*
;
Humans
;
Lung
;
Mastectomy, Segmental
;
Radiotherapy, Intensity-Modulated
;
Skin
;
Surgical Instruments
9.Evaluation of PCR-Reverse Blot Hybridization Assay, REBA Sepsis-ID Test, for Simultaneous Identification of Bacterial Pathogens and mecA and van Genes from Blood Culture Bottles.
Soon Deok PARK ; Gyusang LEE ; Hye Young WANG ; Min PARK ; Sunghyun KIM ; Hyunjung KIM ; Jungho KIM ; Young Keun KIM ; Hyo Youl KIM ; Hyeyoung LEE ; Young UH ; Jong Bae KIM
Annals of Laboratory Medicine 2014;34(6):446-455
BACKGROUND: The aim of this study was to evaluate a newly developed PCR-based reverse blot hybridization assay (PCR-REBA), REBA Sepsis-ID (M&D, Wonju, Korea), to rapidly detect the presence of bacteremia and antimicrobial resistance gene in blood culture samples. METHODS: One thousand four hundred consecutive blood culture samples from patients with a delta neutrophil index greater than 2.7% were selected from March to July in 2013. Three hundred positive and 1,100 negative for bacterial growth in blood culture bottles samples were tested by conventional and real-time PCR-REBA, respectively. RESULTS: The overall agreement between the conventional identification test and the REBA Sepsis-ID test was 95.3% (286/300). Agreement for gram-positive bacteria, gram-negative bacteria, fungi, and polymicrobials was 94.5% (190/201), 97.3% (71/73), 100% (14/14), and 91.7% (11/12), respectively. The detection rate of the mecA gene from methicillin-resistant Staphylococcus isolates was 97.8% (90/92). The vanA gene was detected in one blood culture sample from which vancomycin-resistant Enterococcus was isolated. When the cycle threshold for real-time PCR was defined as 30.0, 2.4% (26/1,100) of negative blood culture samples tested positive by real-time PCR. CONCLUSIONS: The REBA Sepsis-ID test is capable of simultaneously and quickly detecting both causative agents and antimicrobial resistance genes, such as mecA and van, in blood culture positive samples.
Bacteremia/microbiology
;
Bacterial Proteins/*genetics
;
Bacteriological Techniques/*methods
;
Carbon-Oxygen Ligases/*genetics
;
Drug Resistance, Bacterial/genetics
;
Enterococcus/*genetics/isolation & purification
;
Humans
;
Methicillin-Resistant Staphylococcus aureus/*genetics/isolation & purification
;
*Nucleic Acid Hybridization
;
RNA, Ribosomal, 16S/analysis
;
Reagent Kits, Diagnostic
;
*Real-Time Polymerase Chain Reaction
10.Human Papillomavirus Prevalence in Gangwon Province Using Reverse Blot Hybridization Assay.
Dongsup LEE ; Sunghyun KIM ; Sangjung PARK ; Hyunwoo JIN ; Tae Ue KIM ; Kwang Hwa PARK ; Hyeyoung LEE
Korean Journal of Pathology 2011;45(4):348-353
BACKGROUND: Human papillomavirus (HPV) plays an important role in the development of cervical carcinoma. Although there is a general agreement that high levels of HPV are related to cervical cancer, the prevalence and distribution of HPV genotypes seems to vary by geographical region. This study was designed to investigate the prevalence of HPV genotypes in Gangwon Province, Korea. METHODS: In total, 342 samples were examined by Pap smear and HPV-ID(R) reverse blot hybridization assay (REBA) (M&D, Wonju, Korea). RESULTS: Overall HPV positivity was 80.9% and 64.4% in women with abnormal and normal cytology by REBA, respectively. The five most common HPV types were: HPV 16, 53, 58, 56, and 33 in samples with abnormal cytology, and HPV 16, 53, 58, 70, and 18 in samples with normal cytology. CONCLUSIONS: The REBA can provide useful data regarding prevalence of HPV genotypes. Gangwon Province showed high prevalence of HPV infection in women. The most common HPV type in Gangwon Province was HPV16, and HPV 53, 58, 56, 70 were frequently present.
Chimera
;
Female
;
Genotype
;
Human papillomavirus 16
;
Humans
;
Prevalence
;
Uterine Cervical Neoplasms

Result Analysis
Print
Save
E-mail