1.Simultaneous Viability Assessment and Invasive Coronary Angiography Using a Therapeutic CT System in Chronic Myocardial Infarction Patients
Seongmin HA ; Yeonggul JANG ; Byoung Kwon LEE ; Youngtaek HONG ; Byeong-Keuk KIM ; Seil PARK ; Sun Kook YOO ; Hyuk-Jae CHANG
Yonsei Medical Journal 2024;65(5):257-264
Purpose:
In a preclinical study using a swine myocardial infarction (MI) model, a delayed enhancement (DE)-multi-detector computed tomography (MDCT) scan was performed using a hybrid system alongside diagnostic invasive coronary angiography (ICA) without the additional use of a contrast agent, and demonstrated an excellent correlation in the infarct area compared with histopathologic specimens. In the present investigation, we evaluated the feasibility and diagnostic accuracy of a myocardial viability assessment by DE-MDCT using a hybrid system comprising ICA and MDCT alongside diagnostic ICA without the additional use of a contrast agent.
Materials and Methods:
We prospectively enrolled 13 patients (median age: 67 years) with a previous MI (>6 months) scheduled to undergo ICA. All patients underwent cardiac magnetic resonance (CMR) imaging before diagnostic ICA. MDCT viability scans were performed concurrently with diagnostic ICA without the use of additional contrast. The total myocardial scar volume per patient and average transmurality per myocardial segment measured by DE-MDCT were compared with those from DE-CMR.
Results:
The DE volume measured by MDCT showed an excellent correlation with the volume measured by CMR (r=0.986, p<0.0001). The transmurality per segment by MDCT was well-correlated with CMR (r=0.900, p<0.0001); the diagnostic performance of MDCT in differentiating non-viable from viable myocardium using a 50% transmurality criterion was good with a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 87.5%, 99.5%, 87.5%, 99.5%, and 99.1%, respectively.
Conclusion
The feasibility of the DE-MDCT viability assessment acquired simultaneously with conventional ICA was proven in patients with chronic MI using DE-CMR as the reference standard.
2.Tissue Engineered Mini-Cornea Model for Eye Irritation Test
Seon-Hwa KIM ; Sung-Han JO ; Byeong Kook KIM ; Sang-Hyug PARK
Tissue Engineering and Regenerative Medicine 2023;20(2):213-223
BACKGROUND:
Eye irritation tests with animals have been conducted for a long time. However, the subjective decision to irritation, the anatomic/physiologic difference between species and humans, and ethical issues are crucial problems. Various research groups have paid attention to alternative testing methods. In these senses, we fabricated in vitro minicornea models with immortalized human corneal epithelial cells (iHCECs) and keratocytes (iHCKs) and used them for irritation tests. This study hypothesized that our mini-cornea model could present different viability tendencies according to test chemicals with different irritancy levels.
METHODS:
Cells used in this study were characterized with cornea-specific markers by immunocytochemistry and western blot. To make a three-dimensional hemisphere construct like cornea stroma, we cultured iHCKs under modified culture conditions verified by matrix formation and total collagen content. iHCECs were seeded on the construct and cultured at an air–liquid interface. The model was treated with 2-phenoxyethanol, triton X-100, sodium lauryl sulfate, and benzalkonium chloride.
RESULTS:
iHCECs and iHCKs presented their specific cell markers. In modifying the culture condition, the group treating ascorbic acid (200 lg/ml) presented an intact cellular matrix and included the highest collagen content; thus, we used this condition to fabricate the mini-cornea model. The model shows hemisphere shape and homogenous cell distributions in histological analysis. We observed different sensitivity tendencies by types of chemicals, and the model’s viability significantly decreased when the chemical concentration increased.
CONCLUSION
In this study, we performed and observed irritation tests using a tissue-engineered mini-cornea model and considered to apply as an alternative approach for animal tests.
3.Tauroursodeoxycholic Acid Inhibits Nuclear Factor Kappa B Signaling in Gastric Epithelial Cells and Ameliorates Gastric Mucosal Damage in Mice
Su Hwan KIM ; Ji Won KIM ; Seong-Joon KOH ; Sang Gyun KIM ; Jeong Mo BAE ; Jung Ho KIM ; Jeong Hwan PARK ; Mee Soo CHANG ; Kee Don CHOI ; Hyoun Woo KANG ; Byeong Gwan KIM ; Kook Lae LEE
The Korean Journal of Gastroenterology 2022;79(4):161-169
Background/Aims:
Previous studies have reported the protective effects of tauroursodeoxycholic acid (TUDCA) on gastric epithelial cells in some animal models, but the precise mechanisms are unclear. This study examined the effects of TUDCA on NF-κB signaling in gastric epithelial cells. Moreover, the protective effects of TUDCA in experimental gastritis models induced by ethanol and NSAID were evaluated and compared with ursodeoxycholic acid (UDCA).
Methods:
After a pretreatment with TUDCA or UDCA, human gastric epithelial MKN-45 cells were stimulated with tumor necrosis factor (TNF)-α to activate NF-κB signaling. A real-time PCR (RT-PCR) for human interleukin (IL)-1 mRNA was performed. An electrophoretic mobility shift assay (EMSA) and immunoblot analyses were carried out. In murine models, after a pretreatment with TUDCA or UDCA, ethanol and indomethacin were administered via oral gavage. Macroscopic and microscopic assessments were performed to evaluate the preventive effects of TUDCA and UDCA on murine gastritis.
Results:
A pretreatment with TUDCA downregulated the IL-1α mRNA levels in MKN-45 cells stimulated with TNF-α, as assessed by RT-PCR. As determined using EMSA, a pretreatment with TUDCA reduced the TNF-α-induced NF-κB DNA binding activity. A pretreatment with TUDCA inhibited IκBα phosphorylation induced by TNF-α, as assessed by immunoblot analysis. TUDCA attenuated the ethanol-induced and NSAID-induced gastritis in murine models, as determined macroscopically and microscopically.
Conclusions
TUDCA inhibited NF-κB signaling in gastric epithelial cells and ameliorated ethanol- and NSAID-induced gastritis in murine models. These results support the potential of TUDCA for the prevention of gastritis in humans.
4.Corneal Repair with Adhesive Cell Sheets of Fetal Cartilage-Derived Stem Cells
In-Su PARK ; Byeong Kook KIM ; Minh-Dung TRUONG ; Hong Seok YANG ; Sang-Hyug PARK ; Hyo Soon PARK ; Byung Hyune CHOI ; Bae Hie WON ; Byoung-Hyun MIN
Tissue Engineering and Regenerative Medicine 2021;18(1):187-198
BACKGROUND:
Corneal scarring or disease may lead to severe corneal opacification and consequently, severe loss of vision due to the complete loss of corneal epithelial cells. We studied the use of epithelial cell sheets differentiated from fetal cartilage-derived stem cells (FCSC) to resurface damaged cornea.
METHODS:
The FCSC were isolated from the femoral head of immature cartilage tissue. The ability of the FCSCs to differentiate into corneal epithelial cells was evaluated using differentiation media at 2 days and 7 days post-seeding. A sheet fabricated of FCSCs was also used for the differentiation assay. The results of the in vitro studies were evaluated by immunocytochemistry and Western blots for corneal epithelial cell markers (CK3/12 and Pax6) and limbal epithelial stem cell markers (ABCG2 and p63). To test the material in vivo, an FCSC-sheet was applied as a treatment in a chemically burned rabbit model. The healing ability was observed histologically one week after treatment.
RESULTS:
The in vitro experiments showed morphological changes in the FCSCs at two and seven days of culture. The differentiated cells from the FCSCs or the FCSC-sheet expressed corneal epithelial cells markers. FCSC were create cell sheet that successfully differentiated into corneal epithelial cells and had sufficient adhesion so that it could be fused to host tissue after suture to the ocular surface with silk suture. The implanted cell sheet maintained its transparency and the cells were alive a week after implantation.
CONCLUSION
These results suggest that carrier-free sheets fabricated of FCSCs have the potential to repair damaged corneal surfaces.
5.Corneal Repair with Adhesive Cell Sheets of Fetal Cartilage-Derived Stem Cells
In-Su PARK ; Byeong Kook KIM ; Minh-Dung TRUONG ; Hong Seok YANG ; Sang-Hyug PARK ; Hyo Soon PARK ; Byung Hyune CHOI ; Bae Hie WON ; Byoung-Hyun MIN
Tissue Engineering and Regenerative Medicine 2021;18(1):187-198
BACKGROUND:
Corneal scarring or disease may lead to severe corneal opacification and consequently, severe loss of vision due to the complete loss of corneal epithelial cells. We studied the use of epithelial cell sheets differentiated from fetal cartilage-derived stem cells (FCSC) to resurface damaged cornea.
METHODS:
The FCSC were isolated from the femoral head of immature cartilage tissue. The ability of the FCSCs to differentiate into corneal epithelial cells was evaluated using differentiation media at 2 days and 7 days post-seeding. A sheet fabricated of FCSCs was also used for the differentiation assay. The results of the in vitro studies were evaluated by immunocytochemistry and Western blots for corneal epithelial cell markers (CK3/12 and Pax6) and limbal epithelial stem cell markers (ABCG2 and p63). To test the material in vivo, an FCSC-sheet was applied as a treatment in a chemically burned rabbit model. The healing ability was observed histologically one week after treatment.
RESULTS:
The in vitro experiments showed morphological changes in the FCSCs at two and seven days of culture. The differentiated cells from the FCSCs or the FCSC-sheet expressed corneal epithelial cells markers. FCSC were create cell sheet that successfully differentiated into corneal epithelial cells and had sufficient adhesion so that it could be fused to host tissue after suture to the ocular surface with silk suture. The implanted cell sheet maintained its transparency and the cells were alive a week after implantation.
CONCLUSION
These results suggest that carrier-free sheets fabricated of FCSCs have the potential to repair damaged corneal surfaces.
6.Analysis of Prognosis according to Type of Health Insurance in Five Major Gastrointestinal Cancer Patients in Public Hospitals: Single-institution Retrospective Study
Dong Seok LEE ; Jaekyung LEE ; Ji Won KIM ; Kook Lae LEE ; Byeong Gwan KIM ; Su Hwan KIM ; Yong Jin JUNG
The Korean Journal of Gastroenterology 2020;75(1):17-22
BACKGROUND/AIMS: Public hospitals were established to provide high quality medical services to low socioeconomic status patients. This study examined the effects of public hospitals on the treatment and prognosis of patients with five-major gastrointestinal (GI) cancers (stomach cancer, colon cancer, liver cancer, bile duct cancer, and pancreatic cancer).METHODS: Among the 1,268 patients treated at Seoul National University Boramae Medical Center from January 2010 to December 2017, 164 (13%) were in the medicare group. The data were analyzed to identify and compare the clinical manifestations, treatment modality, and clinical outcomes between the groups.RESULTS: No statistically significant differences in the clinical data (age, sex), treatment method, and five-year survival rate were observed between the health insurance group and medicare group in the five major GI cancer patients. On the other hand, some medicare group patients tended more comorbidities and fewer treatment options than health insurance patients.CONCLUSIONS: Public hospitals have a positive effect on the treatment and prognosis in medicare group patients with the five-major GI cancers.
Bile Duct Neoplasms
;
Colonic Neoplasms
;
Comorbidity
;
Gastrointestinal Neoplasms
;
Hand
;
Hospitals, Public
;
Humans
;
Insurance Coverage
;
Insurance, Health
;
Liver Neoplasms
;
Medicare
;
Methods
;
Prognosis
;
Retrospective Studies
;
Seoul
;
Social Class
;
Survival Rate
7.Prognostic Value of the Alcoholic Hepatitis Histologic Score in Korean Patients with Biopsy-Proven Alcoholic Hepatitis
Dong Hyeon LEE ; Youn I CHOI ; Jeong Mo BAE ; Mee Soo CHANG ; Sae Kyung JOO ; Yong Jin JUNG ; Kook Lae E LEE ; Byeong Gwan KIM ; Won KIM
Gut and Liver 2020;14(5):636-643
Background/Aims:
The alcoholic hepatitis histologic score (AHHS) is a recently developed clinical model for predicting short-term mortality in Caucasian patients with alcoholic hepatitis (AH). The AHHS has not been extensively validated in other ethnic populations. This study validated the AHHS in a Korean patient cohort.
Methods:
We conducted a pro-spective cohort study of hospitalized Korean patients with AH between January 2010 and August 2017. Histopatho-logical findings were assessed to determine the AHHS in all study subjects. Histopathological risk factors were examined by Cox regression analysis to predict overall survival (OS).Kaplan-Meier curves were plotted to assess the diagnostic performance of the AHHS.
Results:
We recruited a total of 107 patients with biopsy-proven AH. None of the individual AHHS components were associated with 3-month mortality.However, the bilirubinostasis type and fibrosis severity were significantly associated with AH mortality beyond 6 months (all p<0.05, except fibrosis severity for 6-month mortality) and OS (all p<0.05). The modified AHHS classification as a binary variable (<5 vs ≥5) was also associated with OS (haz-ard ratio, 2.88; 95% confidence interval [CI], 1.50 to 5.56;p=0.002), and had higher predictive performance for OS (concordance index [C-index], 0.634; 95% CI, 0.561 to 0.707) than the original AHHS classification (mild vs moderate vs severe: C-index, 0.577; 95% CI, 0.498 to 0.656). This differ-ence was statistically significant (p=0.045).
Conclusions
In this prospective Korean AH cohort, the modified AHHS was significantly associated with OS. Therefore, the AHHS might be a useful histological prognosticator for long-term progno-sis in patients with nonsevere AH.
8.Clinical and Endoscopic Features of Colonic Anisakiasis in Korea
Sae Kyung JOO ; Ji Won KIM ; Byeong Gwan KIM ; Won KIM ; Jae Kyung LEE ; Kook Lae LEE
The Korean Journal of Parasitology 2019;57(4):411-416
To analyze the clinical and endoscopic features of colonic anisakiasis. A retrospective chart review of 20 patients with colonic anisakiasis, who were diagnosed by colonoscopy at 8 hospitals between January 2002 and December 2011, was performed. Patients’ mean age was 53.6±10.74 years. Seventy percent patients were men. Acute abdominal pain was a common symptom that mostly developed within 48 hr after the ingestion of raw fish, and which lasted for 1–28 days. Sixty percent patients had ingested raw fish before the diagnosis of colonic anisakiasis and 40% patients were incidentally found to have colonic anisakiasis during the screening colonoscopies. Leukocytosis and eosinophilia were each found in 20% of the patients. In all patients who underwent colonoscopy, the worms were removed with biopsy forceps, except in 1 case, and a definite diagnosis of anisakiasis was made. In some cases of colonic anisakiasis, colonoscopy may be helpful in the diagnosis and treatment to avoid surgical intervention.
Abdominal Pain
;
Anisakiasis
;
Biopsy
;
Colon
;
Colonoscopy
;
Diagnosis
;
Eating
;
Eosinophilia
;
Humans
;
Korea
;
Leukocytosis
;
Male
;
Mass Screening
;
Retrospective Studies
;
Surgical Instruments
9.Technical Feasibility of a Guidetube for Various Endoscopic Procedures in Human Gastrointestinal Simulators
Dong Seok LEE ; Byeong Gwan KIM ; Kook Lae LEE ; Yong Jin JUNG ; Ji Won KIM
Clinical Endoscopy 2019;52(3):247-251
BACKGROUND/AIMS: Many gastrointestinal (GI) endoscopic procedures are difficult and cumbersome owing to the limitation of currently available endoscopic devices. This study aimed to develop an endoscopic guidetube for multipurpose endoscopic procedures and assess its use in a realistic GI endoscopic simulator. METHODS: The guidetube used is a soft overtube composed of neoprene and is designed to assist various endoscopic procedures on demand. In total, 15 types of procedures were performed in GI simulators. Four procedures were performed in the stomach model and 11 in the colon model. The procedures include repeated endoscopic insertion and foreign body removal in various positions. The mean insertion and procedure time were assessed in each session. All procedures were performed by 5 expert endoscopists. RESULTS: Endoscopic procedures with the new guidetube were faster and more effective than the conventional endoscopic techniques. The mean insertion time of the endoscope with the guidetube was significantly shorter than that without the guidetube. The guidetube was safely inserted without scratch using low pushing force. Objects of various sizes larger than the endoscopic channel were easily removed by the guidetube-assisted endoscopic procedures. CONCLUSIONS: This preliminary study shows that guidetube-assisted endoscopic procedures are faster, easier, safer and cheaper than conventional endoscopic procedures.
Colon
;
Endoscopes
;
Foreign Bodies
;
Humans
;
Neoprene
;
Stomach
10.Development of Printable Natural Cartilage Matrix Bioink for 3D Printing of Irregular Tissue Shape.
Chi Sung JUNG ; Byeong Kook KIM ; Junhee LEE ; Byoung Hyun MIN ; Sang Hyug PARK
Tissue Engineering and Regenerative Medicine 2018;15(2):155-162
The extracellular matrix (ECM) is known to provide instructive cues for cell attachment, proliferation, differentiation, and ultimately tissue regeneration. The use of decellularized ECM scaffolds for regenerative-medicine approaches is rapidly expanding. In this study, cartilage acellular matrix (CAM)-based bioink was developed to fabricate functional biomolecule-containing scaffolds. The CAM provides an adequate cartilage tissue–favorable environment for chondrogenic differentiation of cells. Conventional manufacturing techniques such as salt leaching, solvent casting, gas forming, and freeze drying when applied to CAM-based scaffolds cannot precisely control the scaffold geometry for mimicking tissue shape. As an alternative to the scaffold fabrication methods, 3D printing was recently introduced in the field of tissue engineering. 3D printing may better control the internal microstructure and external appearance because of the computer-assisted construction process. Hence, applications of the 3D printing technology to tissue engineering are rapidly proliferating. Therefore, printable ECM-based bioink should be developed for 3D structure stratification. The aim of this study was to develop printable natural CAM bioink for 3D printing of a tissue of irregular shape. Silk fibroin was chosen to support the printing of the CAM powder because it can be physically cross-linked and its viscosity can be easily controlled. The newly developed CAM-silk bioink was evaluated regarding printability, cell viability, and tissue differentiation. Moreover, we successfully demonstrated 3D printing of a cartilage-shaped scaffold using only this CAM-silk bioink. Future studies should assess the efficacy of in vivo implantation of 3D-printed cartilage-shaped scaffolds.
Cartilage*
;
Cell Survival
;
Cues
;
Extracellular Matrix
;
Fibroins
;
Freeze Drying
;
Printing, Three-Dimensional*
;
Regeneration
;
Silk
;
Tissue Engineering
;
Viscosity

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