• Proceedings of the KACD Conference
• /
• 2003.11a
• /
• pp.546.2-546
• /
• 2003

Dental follicle is the mesenchymal tissue which surrounds developing tooth germ. During tooth root development, periodontal components such as cementum, periodontal ligament and alveolar bone are considered to be created by progenitors present in the dental follicle. However, little is known about these progenitors. Previously we observed that cultured bovine dental follicle cells (BDFC) contained putative cementoblast progenitors. To further analyze the biology of these cells, we have attempted to immortalize BDFC by expression of the polycomb group protein Bmi-1 and human telomerase reverse transcriptase (hTERT). The BDFC expressing Bmi-1 and hTERT showed extended life span by 90 population doublings more than normal BDFC, and still contained cells with potential to differentiate into cementoblasts upon implantation into immunodeficiency mice. Among them, we established a clonal cell line designated as BCPb8, which formed cemetum-like mineralized tissue reactive to anti-cementum specific monoclonal antibody, 3G9, and expressed mRNA for bone sialoprotein, osteocalcin, osteopontin and type I collagen upon implantation. Thus with the combination of hTERT and Bmi-1, we succeeded in immortalization of cementoblast progenitor in BDFC without affecting differentiation potential. The BCPb8 progenitor cell line could be a useful tool not only to study cementogenesis but also to develop regeneration therapy for periodontitis.

• Journal of Korean Neurosurgical Society
• /
• v.53 no.6
• /
• pp.323-330
• /
• 2013

Objective : To develop a simple, reproducible model of disc degeneration in rabbits through percutaneous annular puncture and to confirm the degree of degeneration over time. Methods : Fifteen New Zealand white rabbits (4 to 5 months old and weighing approximately 3 to 3.5 kg each) underwent annular puncture of the L2-L3, L3-L4, and L4-L5 discs. Rabbits were sacrificed at 4, 8, or 20 weeks after puncture. For a longitudinal study to assess changes in disc height over time, serial X-rays were performed at 0, 2, 4, 8, and 20 weeks for rabbits in the 20-week group. Upon sacrifice, the whole spinal column and discs were extracted and analyzed with magnetic resonance imaging (MRI), real time reverse transcriptase-polymerase chain reaction, and histological staining. Results : The X-rays showed a slow, progressive decrease in disc height over time. Significant disc space narrowing compared to preoperative disc height was observed during the time period (p<0.001). The MRI grade, aggrecan, and matrix metalloprotease-13 mRNA expression and hematoxylin and eosin/safranin O/anti-collagen II staining were consistently indicative of degeneration, supporting the results of the X-ray data. Conclusion : Percutaneous annular puncture resulted in slow, reproducible disc degeneration that was confirmed by radiology, biochemistry, and histology. This in vivo model can be used to study and evaluate the safety and efficacy of biologic treatments for degenerative disc disease.

• Journal of Cancer Prevention
• /
• v.21 no.3
• /
• pp.135-143
• /
• 2016

Background: Fraxetin (7,8-dihydroxy-6-methoxy coumarin), a coumarin derivative, has been reported to possess antioxidative, anti-inflammatory and neuroprotective effects. A number of recent observations suggest that the induction of heme oxygenase-1 (HO-1) inhibits inflammation and tumorigenesis. In the present study, we determined the effect of fraxetin on HO-1 expression in HaCaT human keratinocytes and investigated its underlying molecular mechanisms. Methods: Reverse transcriptase-PCR and Western blot analysis were performed to detect HO-1 mRNA and protein expression, respectively. Cell viability was measured by the MTS test. The induction of intracellular reactive oxygen species (ROS) by fraxetin was evaluated by 2′,7′-dichlorofluorescin diacetate staining. Results: Fraxetin upregulated mRNA and protein expression of HO-1. Incubation with fraxetin induced the localization of nuclear factor-erythroid-2-related factor-2 (Nrf2) in the nucleus and increased the antioxidant response element-reporter gene activity. Fraxetin also induced the phosphorylation of Akt and AMP-activated protein kinase $(AMPK){\alpha}$ and diminished the expression of phosphatase and tensin homolog, a negative regulator of Akt. Pharmacological inhibition of Akt and $AMPK{\alpha}$ abrogated fraxetin-induced expression of HO-1 and nuclear localization of Nrf2. Furthermore, fraxetin generated ROS in a concentration-dependent manner. Conclusions: Fraxetin induces HO-1 expression through activation of Akt/Nrf2 or $AMPK{\alpha}/Nrf2$ pathway in HaCaT cells.

• Allergy, Asthma & Respiratory Disease
• /
• v.6 no.6
• /
• pp.290-294
• /
• 2018

Purpose: We evaluated the clinical features of croup in children according to viral etiology. Methods: This study enrolled pediatric patients with croup, who showed positive results on respiratory virus reverse transcriptase polymerase chain reaction performed between January 2012 and December 2017. We retrospectively reviewed the medical records. Results: A total of 179 patients (119 boys and 60 girls) were enrolled with the mean age of $18.9{\pm}14.7$ months. The viruses commonly identified were parainfluenza, respiratory syncytial virus, rhinovirus, and influenza. Among these 4 viruses, patients with rhinovirus infection showed significantly shorter fever and admission durations. Patients with parainfluenza infection showed significantly lower incidences of epinephrine nebulization and patients with influenza infections showed significantly higher incidences of steroid treatment. Conclusion: Clinical manifestations of croup differ according to causative viruses. Further studies should be conducted to evaluate the severity and prognosis of croup according to viral etiology.

• YAKHAK HOEJI
• /
• v.57 no.1
• /
• pp.70-75
• /
• 2013

The present study was designed to determine the effect of the Sandalwood Essential Oil (Santalum album) on pro-inflammatory factors such as NO, iNOS expression and IL-$1{\beta}$, IL-6, TNF-${\alpha}$ in lipopolysaccharide (LPS) - stimulated RAW264.7 macrophages cells. The cell toxicity was determined by MTS assay. To evaluate of anti-inflammatory effect of Sandalwood Essential Oil, amount of NO was measured using the NO detection kit and the iNOS expression was measured by western blot analysis and reverse transcriptase polymerase chain reaction (RT-PCR). And proinflammatory cytokines were measured by ELISA kit. As a result, Sandalwood Essential Oil reduced NO, iNOS expression and IL-$1{\beta}$, IL-6, TNF-${\alpha}$ production without cytotoxicity. Our results suggest that the Sandalwood Essential Oil may have an anti-inflammatory property through suppressing inflammatory mediator productions and appears to be useful as an anti-inflammatory oil.

• Journal of Plant Biology
• /
• v.39 no.4
• /
• pp.265-271
• /
• 1996

Full-length cDNA for RNA2 of cucumber mosaic virus strian Kor (Kor-CMV) was cloned downstream of synthetic T7 promoter by reverse transcriptase-polymerase chain reaction (RT-PCR). The clone could generate a full-length transcript corresponding to RNA1 in size when synthesized by T7 RNA polymerase. The complete nucleotide sequence has shown that the RNA2 is composed of 3,049 nucleotides and contains one functional open reading frame (ORF) of 2,574 nucleotides encoding 2a protein. The deduced translation product of the 2,574 nucleotides contains GDD motif which is a characteristic of RNA-dependent RNA polymerase (RdRp). The amino acid sequence analysis of the 2a protein has shown that the homology is found in decreasing order with O-CMV (98.8%), Y-CMV (98.7%), Fny-CMV (98.3%), KCMV (94.9%), Ix-CMV (91.9%), and Q-CMV (74.9%). Kor-CMV is suggested to belong to subgroup Ⅰ in the aspect of nucleotide sequence homology of RNA2.

• International Journal of Oral Biology
• /
• v.44 no.2
• /
• pp.62-70
• /
• 2019

Xylitol is well-known to have an anti-caries effect by inhibiting the replication of cariogenic bacteria. In addition, xylitol enhances saliva secretion. However, the precise molecular mechanism of xylitol on saliva secretion is yet to be elucidated. Thus, in this study, we aimed to investigate the stimulatory effect of xylitol on saliva secretion and to further evaluate the involvement of xylitol in muscarinic type 3 receptor (M3R) signaling. For determining these effects, we measured the saliva flow rate following xylitol treatment in healthy individuals and patients with dry mouth. We further tested the effects of xylitol on M3R signaling in human salivary gland (HSG) cells using real-time quantitative reverse-transcriptase polymerase chain reaction, immunoblotting, and immunostaining. Xylitol candy significantly increased the salivary flow rate and intracellular calcium release in HSG cells via the M3R signaling pathway. In addition, the expressions of M3R and aquaporin 5 were induced by xylitol treatment. Lastly, we investigated the distribution of M3R and aquaporin 5 in HSG cells. Xylitol was found to activate M3R, thereby inducing increases in $Ca^{2+}$ concentration. Stimulation of the muscarinic receptor induced by xylitol activated the internalization of M3R and subsequent trafficking of aquaporin 5. Taken together, these findings suggest a molecular mechanism for secretory effects of xylitol on salivary epithelial cells.

• Genomics & Informatics
• /
• v.16 no.4
• /
• pp.25.1-25.5
• /
• 2018

Coronary artery disease (CAD) is one of the leading causes of death and disability all around the world. Recent studies have revealed that aberrantly regulated long non-coding RNA (lncRNA) as one of the main classes of cellular transcript plays a key regulatory role in transcriptional and epigenetic pathways. Recent reports have demonstrated that circulating lncRNAs in the blood can be potential biomarkers for CAD. HOTAIR is one of the most cited lncRNAs with a critical role in the initiation and progression of the gene expression regulation. Recent research on the role of the HOTAIR in cardiovascular disease lays the basis for the development of new studies considering this lncRNA as a potential biomarker and therapeutic target in CAD. In this study, we aimed to compare the expression of HOTAIR lncRNA in the blood samples of patients with CAD and control samples. The expression level was examined by semi-quantitative reverse transcriptase polymerase chain reaction technique. Our data shows that expression of HOTAIR is up-regulated in blood samples of patients with CAD.

• Korean Journal of Veterinary Service
• /
• v.44 no.1
• /
• pp.35-43
• /
• 2021

Rabbit infectious hemorrhagic fever has been reported in rabbits worldwide. The disease is also frequently reported on Korean rabbit farms, and the pathological study of 9 rabbits on such disease-occurring farms was attempted to identify the pathogen. Clinical signs were torticollis and ear ulceration. Most rabbit died with bloody nasal discharges. At necropsy, multiple hemorrhages and inflammation were observed in heart, lung, liver and uterus. The main histopathologic features were hemorrhagic suppurative meningoencephalitis, fibrinous bronchointerstitial pneumonia, bacteremia, liver cell necrosis, multifocal hemorrhages in kidney and disseminated intravascular coagulopathy. The viral VP60 gene of RHDV was identified by Reverse Transcriptase PCR. Pasteurella multocida organisms were cultured, identified by biochemical test and serotyped as A by multiplex capsular typing PCR. In conclusion, the fatal hemorrhagic disease was due to combined infection with both RHDV and P. multocida in rabbits. To our knowledge, this is the first case report about co-infection with both RHDV and P. multocida in rabbits in Korea.

• International Journal of Oral Biology
• /
• v.46 no.1
• /
• pp.39-44
• /
• 2021

This study aimed to investigate whether neurotransmitter receptors in the nervous system were also expressed in oral keratinocytes. Expressions of various neurotransmitter receptor genes in immortalized mouse oral keratinocyte (IMOK) cells were examined by reverse transcriptase polymerase chain reaction. IMOK cells expressed calcitonin gene-related peptide (CGRP) receptor subunit genes Ramp1 and Ramp3 and glutamate receptor subunit genes Grina, Gria3, Grin1, Grin2a, and Grin2d. Moreover, IMOK cells expressed Adrb2 and Chrna5 that encode beta 2 adrenergic receptor and cholinergic receptor nicotinic alpha 5 for sympathetic and parasympathetic neurotransmitters, respectively. The expression of Bdkrb1 and Ptger4, which encode receptors for bradykinin and prostaglandin E2 involved in inflammatory responses, was also observed at low levels. Expressions of Ramp1 and Grina in the mouse gingival epithelium were also confirmed by immunohistochemistry. When the function of neurotransmitter receptors expressed on IMOK cells was tested by intracellular calcium response, CGRP, glutamate, and cholinergic receptors did not respond to their agonists, but the bradykinin receptor responded to bradykinin. Collectively, oral keratinocytes express several neurotransmitter receptors, suggesting the potential regulation of oral epithelial homeostasis by the nervous system.