1.Associations among the Duodenal Ecosystem, Gut Microbiota, and Nutrient Intake in Functional Dyspepsia
Sang Hoon KIM ; Yura CHOI ; Jihong OH ; Eui Yeon LIM ; Jung Eun LEE ; Eun-Ji SONG ; Young-Do NAM ; Hojun KIM
Gut and Liver 2024;18(4):621-631
Background/Aims:
Functional dyspepsia (FD) has long been regarded as a syndrome because its pathophysiology is multifactorial. However, recent reports have provided evidence that changes in the duodenal ecosystem may be the key. This study aimed to identify several gastrointestinal factors and biomarkers associated with FD, specifically changes in the duodenal ecosystem that may be key to understanding its pathophysiology.
Methods:
In this case-control study, 28 participants (12 with FD and 16 healthy control individuals) were assessed for dietary nutrients, gastrointestinal symptom severity, immunological status of the duodenal mucosa, and microbiome composition from oral, duodenal, and fecal samples. Integrated data were analyzed using immunohistochemistry, real-time polymerase chain reaction, 16S rRNA sequencing, and network analysis.
Results:
Duodenal mucosal inflammation and impaired expression of tight junction proteins were confirmed in patients with FD. The relative abundance of duodenal Streptococcus (p=0.014) and reductions in stool Butyricicoccus (p=0.047) were confirmed. These changes in the gut microbiota were both correlated with symptom severity. Changes in dietary micronutrients, such as higher intake of valine, were associated with improved intestinal barrier function and microbiota.
Conclusions
This study emphasizes the relationships among dietary nutrition, oral and gut microbiota, symptoms of FD, impaired function of the duodenal barrier, and inflammation. Assessing low-grade inflammation or increased permeability in the duodenal mucosa, along with changes in the abundance of stool Butyricicoccus, is anticipated to serve as effective biomarkers for enhancing the objectivity of FD diagnosis and monitoring.
2.Rising Incidence of Diabetes in Young Adults in South Korea: A National Cohort Study
Hyun Ho CHOI ; Giwoong CHOI ; Hojun YOON ; Kyoung Hwa HA ; Dae Jung KIM
Diabetes & Metabolism Journal 2022;46(5):803-807
We investigated the incidence of diagnosed diabetes in South Korean adults (aged ≥20 years) by analyzing data for the National Health Insurance Service–National Sample Cohort. From 2006 to 2015, the overall incidence rate of diagnosed diabetes decreased by approximately 0.1% per year until 2015. Although, this trend was observed in individuals aged 40 years or over, the rate increased slightly in the 20–29 and 30–39 years age groups, from 0.5 to 0.7 and 2.0 to 2.6 per 1,000 individuals, respectively. The proportion of obese young adults with diabetes increased remarkably, from 51.4% in 2006 to 72.4% in 2015. Thus, young adults need early identification and weight-control strategies to prevent diabetes.
3.Case of Crohn’s Disease Initially Misdiagnosed as Intestinal Tuberculosis Due to Active Pulmonary Tuberculosis
Sumin PARK ; Taeyeong LEE ; Won LIM ; Sangkyu PARK ; Hojun PARK ; Jeonghui YUN ; Dohyeong KIM ; Sooryong CHOI ; Heetaek OH ; Chulsoo SONG
The Korean Journal of Gastroenterology 2021;77(1):30-34
Differentiating Crohn’s disease (CD) from intestinal tuberculosis (TB) is a challenge. In patients suspected of having CD or intestinal TB compounded with active pulmonary TB in its early stages, clinicians often lean towards a diagnosis of intestinal TB. A 14-year-old female patient was admitted with symptoms of abdominal pain and diarrhea with hematochezia. Colonoscopy revealed a stricture of the ileocecal valve and scattered longitudinal ulcers. Initial chest radiography showed consolidation in the left lower lobe of the lung. Chest CT revealed branching nodular opacities and consolidation. The TB PCR of the bronchial washing fluid was positive. The patient was diagnosed with pulmonary and intestinal TB. The colonoscopy findings favored CD. Despite this, anti-tubercular therapy was initiated based on the radiology findings and PCR test. After treatment with anti-tubercular therapy, the patient’s diarrhea and abdominal pain worsened despite the improvement observed on her chest radiography. Follow-up colonoscopy revealed aggravation of her ulcers. The patient was diagnosed with CD and treated with prednisolone and mesalazine. Her clinical condition improved, and follow-up colonoscopy showed significant improvement of the ulcers. This case highlights the need for caution in diagnosis and suggests that clinicians consider reevaluation in similar cases.
4.Biodistribution of Exosomes and Engineering Strategies for Targeted Delivery of Therapeutic Exosomes
Hojun CHOI ; Yoorim CHOI ; Hwa Young YIM ; Amin MIRZAAGHASI ; Jae-Kwang YOO ; Chulhee CHOI
Tissue Engineering and Regenerative Medicine 2021;18(4):499-511
Exosomes are cell-secreted nano-sized vesicles which deliver diverse biological molecules for intercellular communication. Due to their therapeutic potential, exosomes have been engineered in numerous ways for efficient delivery of active pharmaceutical ingredients to various target organs, tissues, and cells. In vivo administered exosomes are normally delivered to the liver, spleen, kidney, lung, and gastrointestinal tract and show rapid clearance from the blood circulation after systemic injection. The biodistribution and pharmacokinetics (PK) of exosomes can be modulated by engineering various factors such as cellular origin and membrane protein composition of exosomes. Recent advances accentuate the potential of targeted delivery of engineered exosomes even to the most challenging organs including the central nervous system. Major breakthroughs have been made related to various imaging techniques for monitoring in vivo biodistribution and PK of exosomes, as well as exosomal surface engineering technologies for inducing targetability. For inducing targeted delivery, therapeutic exosomes can be engineered to express various targeting moieties via direct modification methods such as chemically modifying exosomal surfaces with covalenton-covalent bonds, or via indirect modification methods by genetically engineering exosome-producing cells. In this review, we describe the current knowledge of biodistribution and PK of exosomes, factors determining the targetability and organotropism of exosomes, and imaging technologies to monitor in vivo administered exosomes. In addition, we highlight recent advances in strategies for inducing targeted delivery of exosomes to specific organs and cells.
5.Roles of Type I and III Interferons in COVID-19
Yonsei Medical Journal 2021;62(5):381-390
Coronavirus disease 2019 (COVID-19) is an ongoing global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Type I and III interferon (IFN) responses act as the first line of defense against viral infection and are activated by the recognition of viruses by infected cells and innate immune cells. Dysregulation of host IFN responses has been known to be associated with severe disease progression in COVID-19 patients. However, the reported results are controversial and the roles of IFN responses in COVID-19 need to be investigated further. In the absence of a highly efficacious antiviral drug, clinical studies have evaluated recombinant type I and III IFNs, as they have been successfully used for the treatment of infections caused by two other epidemic coronaviruses, SARS-CoV-1 and Middle East respiratory syndrome (MERS)-CoV. In this review, we describe the strategies by which SARS-CoV-2 evades IFN responses and the dysregulation of host IFN responses in COVID-19 patients. In addition, we discuss the therapeutic potential of type I and III IFNs in COVID-19.
6.Biodistribution of Exosomes and Engineering Strategies for Targeted Delivery of Therapeutic Exosomes
Hojun CHOI ; Yoorim CHOI ; Hwa Young YIM ; Amin MIRZAAGHASI ; Jae-Kwang YOO ; Chulhee CHOI
Tissue Engineering and Regenerative Medicine 2021;18(4):499-511
Exosomes are cell-secreted nano-sized vesicles which deliver diverse biological molecules for intercellular communication. Due to their therapeutic potential, exosomes have been engineered in numerous ways for efficient delivery of active pharmaceutical ingredients to various target organs, tissues, and cells. In vivo administered exosomes are normally delivered to the liver, spleen, kidney, lung, and gastrointestinal tract and show rapid clearance from the blood circulation after systemic injection. The biodistribution and pharmacokinetics (PK) of exosomes can be modulated by engineering various factors such as cellular origin and membrane protein composition of exosomes. Recent advances accentuate the potential of targeted delivery of engineered exosomes even to the most challenging organs including the central nervous system. Major breakthroughs have been made related to various imaging techniques for monitoring in vivo biodistribution and PK of exosomes, as well as exosomal surface engineering technologies for inducing targetability. For inducing targeted delivery, therapeutic exosomes can be engineered to express various targeting moieties via direct modification methods such as chemically modifying exosomal surfaces with covalenton-covalent bonds, or via indirect modification methods by genetically engineering exosome-producing cells. In this review, we describe the current knowledge of biodistribution and PK of exosomes, factors determining the targetability and organotropism of exosomes, and imaging technologies to monitor in vivo administered exosomes. In addition, we highlight recent advances in strategies for inducing targeted delivery of exosomes to specific organs and cells.
7.Roles of Type I and III Interferons in COVID-19
Yonsei Medical Journal 2021;62(5):381-390
Coronavirus disease 2019 (COVID-19) is an ongoing global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Type I and III interferon (IFN) responses act as the first line of defense against viral infection and are activated by the recognition of viruses by infected cells and innate immune cells. Dysregulation of host IFN responses has been known to be associated with severe disease progression in COVID-19 patients. However, the reported results are controversial and the roles of IFN responses in COVID-19 need to be investigated further. In the absence of a highly efficacious antiviral drug, clinical studies have evaluated recombinant type I and III IFNs, as they have been successfully used for the treatment of infections caused by two other epidemic coronaviruses, SARS-CoV-1 and Middle East respiratory syndrome (MERS)-CoV. In this review, we describe the strategies by which SARS-CoV-2 evades IFN responses and the dysregulation of host IFN responses in COVID-19 patients. In addition, we discuss the therapeutic potential of type I and III IFNs in COVID-19.
8.Construction of an Electrocardiogram Database Including 12 Lead Waveforms.
Dahee CHUNG ; Junggu CHOI ; Jong Hwan JANG ; Tae Young KIM ; JungHyun BYUN ; Hojun PARK ; Hong Seok LIM ; Rae Woong PARK ; Dukyong YOON
Healthcare Informatics Research 2018;24(3):242-246
OBJECTIVES: Electrocardiogram (ECG) data are important for the study of cardiovascular disease and adverse drug reactions. Although the development of analytical techniques such as machine learning has improved our ability to extract useful information from ECGs, there is a lack of easily available ECG data for research purposes. We previously published an article on a database of ECG parameters and related clinical data (ECG-ViEW), which we have now updated with additional 12-lead waveform information. METHODS: All ECGs stored in portable document format (PDF) were collected from a tertiary teaching hospital in Korea over a 23-year study period. We developed software which can extract all ECG parameters and waveform information from the ECG reports in PDF format and stored it in a database (meta data) and a text file (raw waveform). RESULTS: Our database includes all parameters (ventricular rate, PR interval, QRS duration, QT/QTc interval, P-R-T axes, and interpretations) and 12-lead waveforms (for leads I, II, III, aVR, aVL, aVF, V1, V2, V3, V4, V5, and V6) from 1,039,550 ECGs (from 447,445 patients). Demographics, drug exposure data, diagnosis history, and laboratory test results (serum calcium, magnesium, and potassium levels) were also extracted from electronic medical records and linked to the ECG information. CONCLUSIONS: Electrocardiogram information that includes 12 lead waveforms was extracted and transformed into a form that can be analyzed. The description and programming codes in this case report could be a reference for other researchers to build ECG databases using their own local ECG repository.
Calcium
;
Cardiovascular Diseases
;
Demography
;
Diagnosis
;
Drug-Related Side Effects and Adverse Reactions
;
Electrocardiography*
;
Electronic Health Records
;
Hospitals, Teaching
;
Korea
;
Machine Learning
;
Magnesium
;
Potassium
9.Evaluation of Microtensile Bond Strength of Sealant Depending on the Duration of Etching and the Use of Bonding Agent
Seoyoun SHIM ; Hojun SONG ; Sunmi YANG ; Jaehwan KIM ; Seonmi KIM ; Namki CHOI
Journal of Korean Academy of Pediatric Dentistry 2018;45(3):299-305
The aim of this study was to evaluate the effect of etching time and bonding agents on bond strength of sealant applied to the occlusal surface of primary molars.Forty non-carious exfoliated human primary molars were included in the study. The teeth were randomly divided into 4 groups for measurement. For group I, no acid etching treatment was used. For group II, III, and IV, acid etching gels were applied on the occlusal surface for 15, 30, and 60 seconds, respectively. Each group was divided into 2 subgroups; one group was treated with bonding agents on the enamel while the other was not. Microtensile bond strength was evaluated using a universal testing machine.There were no statistically significant differences in bond strength with varying duration of etching among groups. The results revealed that the use of bonding agents prior to application of fissure sealant increased the bond strength(p < 0.05).It could be concluded that etching time greater than 15 seconds does not significantly enhance the bond strength, but the use of bonding agents as an intermediate layer between the primary molar and fissure sealant would be beneficial in increasing the bond strength.
Dental Enamel
;
Gels
;
Humans
;
Molar
;
Pit and Fissure Sealants
;
Tooth
10.The Measurement of the Sensory Recovery Period in Zygoma and Blow-Out Fractures with Neurometer Current Perception Threshold.
Daemyung OH ; Taebin YUN ; Junhyung KIM ; Jaehoon CHOI ; Woonhyeok JEONG ; Hojun CHU ; Soyoung LEE
Archives of Plastic Surgery 2016;43(5):411-417
BACKGROUND: Facial hypoesthesia is one of the most troublesome complaints in the management of facial bone fractures. However, there is a lack of literature on facial sensory recovery after facial trauma. The purpose of this study was to evaluate the facial sensory recovery period for facial bone fractures using Neurometer. METHODS: Sixty-three patients who underwent open reduction of zygomatic and blowout fractures between December 2013 and July 2015 were included in the study. The facial sensory status of the patients was repeatedly examined preoperatively and postoperatively by Neurometer current perception threshold (CPT) until the results were normalized. RESULTS: Among the 63 subjects, 30 patients had normal Neurometer results preoperatively and postoperatively. According to fracture types, 17 patients with blowout fracture had a median recovery period of 0.25 months. Twelve patients with zygomatic fracture had a median recovery period of 1.00 month. Four patients with both fracture types had a median recovery period of 0.625 months. The median recovery period of all 33 patients was 0.25 months. There was no statistically significant difference in the sensory recovery period between types and subgroups of zygomatic and blowout fractures. In addition, there was no statistically significant difference in the sensory recovery period according to Neurometer results and the patients' own subjective reports. CONCLUSIONS: Neurometer CPT is effective for evaluating and comparing preoperative and postoperative facial sensory status and evaluating the sensory recovery period in facial bone fracture patients.
Facial Bones
;
Humans
;
Hypesthesia
;
Orbital Fractures*
;
Zygoma*
;
Zygomatic Fractures

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