1.Recovery of Streptococcus Mutans Biofilm after Photodynamic Therapy with Erythrosine and LED Light Source
Yongwook SHIN ; Howon PARK ; Juhyun LEE ; Siyoung LEE
Journal of Korean Academy of Pediatric Dentistry 2022;49(2):149-157
The aim of this study was to evaluate the effects of erythrosine-mediated photodynamic therapy (PDT) on Streptococcus mutans biofilm recovery by counting its colony-forming units (CFUs) and via confocal laser scanning microscopy analysis at different time points following PDT. In PDT, photosensitizer was an erythrosine. S. mutans ATCC25175 biofilms were irradiated using an LED curing light. Chlorhexidine (CHX) was used as positive control. After each antimicrobial treatment, samples were cultured to allow biofilm recovery. Viability was measured by calculating the CFU counts after treatment and after every 3 hours for up to 24 hours. Immediately after treatment, the PDT and CHX groups showed equally significant decreases in S. mutans CFU counts compared to the negative control. After 12 hours of reculture, the PDT group showed no significant difference in the decrease in CFU count compared to the negative control, whereas the CHX group showed significantly lower CFU counts throughout the 24-hour period. Erythrosine-mediated PDT can effectively inhibit S. mutans biofilm formation. However, biofilm recovery occurred earlier in the CHX group after PDT. This study provides insights into the clinical effectiveness of PDT in preventing dental caries.
2.Eruption Guidance of Distally Displaced Mandibular Second Premolar by the Hemisection of Primary Second Molar: Two Case Reports
Yongwook SHIN ; Howon PARK ; Juhyun LEE
Journal of Korean Academy of Pediatric Dentistry 2022;49(3):340-347
Distal displacement of the tooth germ of the mandibular second premolar (MnP2) leads to its impaction and obturation of the eruption path of the mandibular first molar delaying its eruption. The present case report describes the treatment of 2 cases of eruption guidance for distally displaced developing MnP2 that caused delayed eruption of the mandibular first molar. Intentional extraction of primary predecessor results in the mesial shift of the displaced MnP2. However, unfavorable distal ectopic eruption of the mandibular first premolar after the premature loss of primary second molar has been previously reported. Hemisection and sequential extraction of the mandibular primary second molar were performed to mesially shift the distally displaced MnP2, while preventing unfavorable distal ectopic eruption of the mandibular first premolar.
3.Recent Research and Knowledge on Treatment for Hepatitis B
Hye-won LEE ; Yongwook CHOI ; Yong Kwang PARK
Journal of Bacteriology and Virology 2020;50(3):175-180
Hepatitis B virus (HBV) infection is a major public health problem, with some 250 million people currently at high risk of developing chronic liver diseases. The current antiviral treatment for chronic hepatitis B (CHB) is effective in controlling viral replication but fails to achieve a complete cure. Since the identification of sodium taurocholate cotransport polypeptide (NTCP) as an HBV receptor, anti-HBV drugs targeting viral entry, capsid assembly, cccDNA, transcription, and secretion have been developed. In this paper, the potential inhibitors in various steps of the HBV life cycle are summarized.
4.Overview of anti-Hepatitis B virus agents
Hye-won LEE ; Yong-kwang PARK ; Yongwook CHOI
Journal of Bacteriology and Virology 2020;50(3):141-149
Since the first FDA approval of Lamivudine in 1998, many nucleo(t)side analogs such as Lamivudine, Adefovir, and Entecavir have been used. However, they only inhibit DNA synthesis, and if their administration is stopped a viral breakthrough can develop, making long-term administration necessary, ultimately followed by the development of resistance. Tenofovir has been developed and drug-resistant mutations have decreased significantly, but the problem of resistance due to long-term drug use still remains, along with the drug safety problem. In this review, we introduce the recent trend in the development of hepatitis B treatment agents and the Korea National Research Institute of Health (KNIH) research for the development of a novel treatment for hepatitis B (drug repositioning) without resistance and which targets the various life cycles of HBV.
5.Changes in gallbladder motility in gastrectomized patients.
Joonsoo HAHM ; Joonyong PARK ; Yunju CHO ; Changsoo EUN ; Yongwook LEE ; Hosoon CHOI ; Byoengchul YOON ; Minho LEE ; Choonsuhk KEE ; Kyungnam PARK ; Heonkil LIM ; Sungjoon KWON
The Korean Journal of Internal Medicine 2000;15(1):19-24
OBJECTIVES: Gastric resection may predispose gallstone formation. However, the mechanism has not been clearly understood. To evaluate the relationship between gastric resection and gallstone formation, we compared gallbladder(GB) motility in gastrectomized patients and control subjects. METHODS: We compared the GB volume and ejection fraction of the 46 gastrectomized patients with 37 healthy controls using real time ultrasonography. RESULTS: GB volume increased significantly in the gastrectomized group in fasting (30.2 13.9 ml). The GB volume after a fatty meal was greater in the gastrectomized group (12.6 6.4 ml) than in the control group (4.3 3.3 ml) (p +ADw- 0.01). A significant reduction of ejection fraction was found in gastrectomized patients (56.9 13.0+ACU-) in comparison with the control group (75.5 16.1+ACU-) (p +ADw- 0.01). The GB ejection fraction had a poor correlation to the postoperative period (r +AD0- 0.232). CONCLUSION: A gastrectomy appears to be a risk factor of GB dysmotility, which may play a major role in gallstone formation in gastrectomized patients.
Adult
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Aged
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Cholelithiasis/ultrasonography
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Cholelithiasis/etiology+ACo-
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Comparative Study
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Eating
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Endosonography
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Fasting
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Female
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Gallbladder/ultrasonography
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Gallbladder/physiopathology+ACo-
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Gallbladder Emptying
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Gastrectomy/adverse effects+ACo-
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Gastrointestinal Motility
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Human
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Male
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Middle Age
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Probability
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Prospective Studies
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Reference Values
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Risk Assessment
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Stomach Neoplasms/surgery+ACo-
6.Kinesin Superfamily KIF1Balpha Protein Binds to the PDZ Domain of MALS-3.
Sang Jin KIM ; Chul Hee LEE ; Hye Young PARK ; Sung Su YEA ; Won Hee JANG ; Sang Kyeong LEE ; Yeong Hong PARK ; Yongwook JUNG ; Dae Hyun SEOG
Korean Journal of Anatomy 2006;39(5):375-382
The Kinesin superfamily proteins (KIFs) make up a large superfamily of molecular motors that transport cargo such as vesicles, protein complexes, and organelles. KIF1Balpha is a monomeric motor that conveys mitochondria and plays an important role in cellular function. Here, we used the yeast two-hybrid system to identify the proteins that interacts with KIF1Balpha and found a specific interaction with the mammalian LIN-7 (MALS)-3/vertebrate homology of LIN-7 (Veri) and synaptic scaffolding molecule (S-SCAM). MALS-3 protein bound to the tail region of KIF1Balpha but not to other kinesin family members in the yeast two-hybrid assay. The "T-X-V" motif at the C-terminal end of KIF1Balpha is essential for interaction with MALS-3. In addition, this protein showed specific interactions in the Glutathione S-transferase (GST) pull-down assay. An antibody to MALS-3 specifically coimmunoprecipitated KIF1Balpha associated with MALS-3 from mouse brain extracts. These results suggest that MALS-3, as KIF1Balpha receptor, is involved in the KIF1Balpha-mediated transport.
Animals
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Brain
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Glutathione Transferase
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Humans
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Kinesin*
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Mice
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Microtubules
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Mitochondria
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Organelles
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PDZ Domains*
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Two-Hybrid System Techniques