1.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
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Gels
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Humans
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Molar
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Pit and Fissure Sealants
;
Tooth
2.Eosinophilic Colitis that Presented with Subepithelial Tumor-like Lesions
Jeonghui YUN ; Sanggyu PARK ; Hojun PARK ; Won LIM ; Taeyeong LEE ; Chulsoo SONG
The Korean Journal of Gastroenterology 2021;77(6):300-304
Eosinophilic colitis is a rare disease that is characterized by eosinophilic infiltration in the colon wall in symptomatic patients. Thus far, the epidemiology and pathophysiology of eosinophilic colitis have not been well defined, but the hypersensitivity response is likely to play a role in its pathogenesis. The clinical presentation of eosinophilic colitis is usually nonspecific and depends on the layer of the intestinal wall affected by the eosinophilic infiltrate. Eosinophilic colitis is diagnosed generally by exclusion, i.e., after all other causes of eosinophilic infiltration have been excluded. Although there is no consensus over its diagnostic criteria, the laboratory results and radiology and endoscopy findings can provide important diagnostic evidence. This paper reports a case of eosinophilic colitis presenting as subepithelial tumor-like lesions in a 41-year-old man with the chief complaints of abdominal pain and loose stools. The patient had no diseases and no food or drug allergies in his medical history. In general, the endoscopic findings of eosinophilic colitis can vary from a normal mucosa to frank ulcerations. In this case, however, endoscopy revealed subepithelial tumor-like lesions. The colon biopsy showed eosinophilic infiltration in the lamina propria. The patient was treated with steroids, and his symptoms regressed with no signs of relapse.
3.The effect of fibroblast growth factor receptor inhibition on resistance exercise training-induced adaptation of bone and muscle quality in mice
Suhan CHO ; Hojun LEE ; Ho-Young LEE ; Sung Joon KIM ; Wook SONG
The Korean Journal of Physiology and Pharmacology 2022;26(3):207-218
Aging in mammals, including humans, is accompanied by loss of bone and muscular function and mass, characterized by osteoporosis and sarcopenia.Although resistance exercise training (RET) is considered an effective intervention, its effect is blunted in some elderly individuals. Fibroblast growth factor (FGF) and its receptor, FGFR, can modulate bone and muscle quality during aging and physical performance. To elucidate this possibility, the FGFR inhibitor NVP-BGJ398 was administrated to C57BL/6n mice for 8 weeks with or without RET. Treatment with NVPBGJ398 decreased grip strength, muscular endurance, running capacity and bone quality in the mice. FGFR inhibition elevated bone resorption and relevant gene expression, indicating altered bone formation and resorption. RET attenuated tibial bone resorption, accompanied by changes in the expression of relevant genes. However, RET did not overcome the detrimental effect of NVP-BGJ398 on muscular function. Taken together, these findings provide evidence that FGFR signaling may have a potential role in the maintenance of physical performance and quality of bone and muscles.
4.Eosinophilic Colitis that Presented with Subepithelial Tumor-like Lesions
Jeonghui YUN ; Sanggyu PARK ; Hojun PARK ; Won LIM ; Taeyeong LEE ; Chulsoo SONG
The Korean Journal of Gastroenterology 2021;77(6):300-304
Eosinophilic colitis is a rare disease that is characterized by eosinophilic infiltration in the colon wall in symptomatic patients. Thus far, the epidemiology and pathophysiology of eosinophilic colitis have not been well defined, but the hypersensitivity response is likely to play a role in its pathogenesis. The clinical presentation of eosinophilic colitis is usually nonspecific and depends on the layer of the intestinal wall affected by the eosinophilic infiltrate. Eosinophilic colitis is diagnosed generally by exclusion, i.e., after all other causes of eosinophilic infiltration have been excluded. Although there is no consensus over its diagnostic criteria, the laboratory results and radiology and endoscopy findings can provide important diagnostic evidence. This paper reports a case of eosinophilic colitis presenting as subepithelial tumor-like lesions in a 41-year-old man with the chief complaints of abdominal pain and loose stools. The patient had no diseases and no food or drug allergies in his medical history. In general, the endoscopic findings of eosinophilic colitis can vary from a normal mucosa to frank ulcerations. In this case, however, endoscopy revealed subepithelial tumor-like lesions. The colon biopsy showed eosinophilic infiltration in the lamina propria. The patient was treated with steroids, and his symptoms regressed with no signs of relapse.
5.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.
6.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.
7.Distribution of hepatitis C virus genotypes in Jeju Island.
Hojun LEE ; Yoo Kyung CHO ; Heung Up KIM ; Eun Kwang CHOI ; Soyoung HYUN ; Donggu KANG ; Seung Uk JEONG ; Hyun Ju KIM ; Kwang Sik KIM ; Byung Cheol SONG
The Korean Journal of Hepatology 2008;14(1):28-35
BACKGROUNDS/AIMS: The hepatitis C virus (HCV) genotype affects clinical outcomes of HCV infection, in terms of the response to antiviral therapy and progression of chronic liver diseases, and shows geographic differences in distribution. The aim of this study was to elucidate the HCV genotypes in patients with chronic HCV infection in Jeju, which is an island off the Korean peninsula. METHODS: The study population consisted of 162 patients with anti-HCV antibodies and HCV-RNA. HCV genotypes were determined using genotype specific primers. RESULTS: HCV genotype 2a predominated (62.3%), followed by genotype 1b (34.0%) and 2b (3.7%). The prevalence of genotypes differed significantly with age, with HCV genotypes 1 and 2 being more frequent in older and younger subjects (P=0.035), respectively. HCV-RNA levels were higher in patients with genotype 1 than in those with genotype 2 (P=0.001). HCV genotype was not significantly related to sex, clinical diagnosis and potential risk factors. CONCLUSIONS: HCV genotype 2a is most common in Jeju, followed by genotype 1b. Our results suggest that the distribution of the HCV genotype differs between regions in Korea.
Aged
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Enzyme-Linked Immunosorbent Assay
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Female
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Genotype
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Hepacivirus/*classification/genetics
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Hepatitis C, Chronic/epidemiology/*virology
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Humans
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Korea
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Male
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Middle Aged
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RNA, Viral/blood
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Rural Population