• International Journal of Oral Biology
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• 제45권4호
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• pp.211-217
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• 2020

Molecular mimicry is the most common mechanism that breaches self-tolerance. We previously identified autoantibodies to aquaporin-5 (AQP5) in the sera of patients with Sjögren's syndrome and found that the aquaporin of Prevotella melaninogenica (PmAqp), an oral commensal, is highly homologous to human AQP5. This study aimed to test whether PmAqp can induce anti-AQP5 autoantibodies via molecular mimicry. From the amino acid sequence of PmAqp, an immunizing peptide; i.e., PmE-L, was designed, which contained both the B cell epitope "E" and T cell epitope. C57BL/6 and BALB/c mice were subcutaneously immunized with linear or cyclic forms of PmE-L emulsified in incomplete Freund's adjuvant. The concentrations of the antibodies in sera were measured using enzyme-linked immunosorbent assays. Both linear and cyclic PmE-L induced high levels of antibodies against not only the immunized peptides but also autoantibodies against AQP5E and antibodies against PmE, a Pm homolog of AQP5E. In C57BL/6 mice; however, the cyclic form of PmE-L was more efficient than the linear form in inducing autoantibodies against AQP5E that contained a cyclic epitope. The levels of anti-PmE antibodies and anti-AQP5E autoantibodies showed a strong positive correlation (r = 0.95, p < 0.0005), suggesting molecular mimicry. Collectively, the mice produced anti-AQP5E autoantibodies in response to a PmAqp-derived peptide. This model proved to be useful for studying the mechanisms of autoantibody production by molecular mimicry.

• 대한치과교정학회지
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• 제23권3호
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• pp.311-318
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• 1993

This study was done to evaluate the effect of fixed orthodontic patients on the level of oral streptococci, Streptococcus mutans, lactobacilli, yeasts in saliva. 35 patients wearing bands were compared with age-matched 35 non-banded control group by conlony counting method on the specially designed culture medium. The following results were obtained ; 1. The colony forming unit(CFU) of total streptocci per militer of saliva in subjects with or without orthodontic treatment showed no significant statistical difference between them(p>0.05). 2. The colony forming unit(CFU) of total Streptococcus mutans per mililiter of saliva in subjects with orthodontic treatment showed significantly higher than those without orthodontic treatment(p<0.05). 3. The colony forming unit(CFU) of total lactobacilli per mililiter of saliva in sujects with or without orthodontic treatment showed no significant statistical difference between them but higher tendency in those with orthodontic treatment(p=0.052). 4. The colony forming unit(CFU) of total yeasts per mililiter of saliva in subjects with or without orthodontic treatment showed no significant statistical difference between them(p>0.05).

• Molecules and Cells
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• 제21권2호
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• pp.244-250
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• 2006

Gangliosides are receptors for various peptides and proteins including neuropeptides, ${\beta}$-amyloid proteins, and prions. Recently, the role of gangliosides in mucosal immunization has attracted attention due to the emerging interest in oral vaccination. Ganglioside GM1 exists in abundance on the surface of the M cells of Peyer's patch, a well-known mucosal immunity induction site. In the present study we identified a peptide ligand for GM1 and tested whether it played a role in immune induction. GM1-binding peptides were selected from a phage-displayed dodecapeptide library and one peptide motif, GWKERLSSWNRF, was fused to the C-terminus of enhanced green fluorescent protein (EGFP). The fusion protein, but not EGFP fused with a control peptide, was concentrated around Peyer's patch after incubation in the lumen of the intestine ex vivo. Furthermore, oral feeding of the fusion protein but not control EGFP induced mucosal and systemic immune responses against EGFP resembling Th2-type immune responses.

• Journal of Pharmaceutical Investigation
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• 제30권4호
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• pp.253-258
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• 2000

In order to design the oral vaccine delivery system, we prepared the alginate micro spheres containing GFP (green fluorescent protein) as a model drug by spray method. To optimize the preparation conditions of microspheres, we investigated the effects of various parameters including nozzle pressure, nozzle opening angle, and concentrations of sodium alginate and calcium chloride. The prepared microspheres were evaluated by measuring their sizes, loading efficiency, and morphology. The particle size of microspheres was affected by the concentration of sodium alginate and calcium chloride, nozzle pressure, and nozzle opening angle. As the concentration of sodium alginate increased, GFP loading efficiency and particles size of microsphere also increased. However, it was observed to be difficult to spray the sodium alginate solution with concentration greater than 1.5% (w/v), due to high viscosity. The pressure over $3\;kgf/cm^2$ didn't affect the size of particles. As a result, the spraying method enabled us to prepare microspheres for oral vaccine delivery system. In this study, microspheres prepared with 1% (w/v) sodium alginate had greater loading efficiency and better spherical shape.

• IMMUNE NETWORK
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• 제12권5호
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• pp.165-175
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• 2012

Vaccination is one of the most effective methods available to prevent infectious diseases. Mucosa, which are exposed to heavy loads of commensal and pathogenic microorganisms, are one of the first areas where infections are established, and therefore have frontline status in immunity, making mucosa ideal sites for vaccine application. Moreover, vaccination through the mucosal immune system could induce effective systemic immune responses together with mucosal immunity in contrast to parenteral vaccination, which is a poor inducer of effective immunity at mucosal surfaces. Among mucosal vaccines, oral mucosal vaccines have the advantages of ease and low cost of vaccine administration. The oral mucosal immune system, however, is generally recognized as poorly immunogenic due to the frequent induction of tolerance against orally-introduced antigens. Consequently, a prerequisite for successful mucosal vaccination is that the orally introduced antigen should be transported across the mucosal surface into the mucosa-associated lymphoid tissue (MALT). In particular, M cells are responsible for antigen up-take into MALT, and the rapid and effective transcytotic activity of M cells makes them an attractive target for mucosal vaccine delivery, although simple transport of the antigen into M cells does not guarantee the induction of specific immune responses. Consequently, development of mucosal vaccine adjuvants based on an understanding of the biology of M cells has attracted much research interest. Here, we review the characteristics of the oral mucosal immune system and delineate strategies to design effective oral mucosal vaccines with an emphasis on mucosal vaccine adjuvants.

• The Korean Journal of Physiology and Pharmacology
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• 제14권3호
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• pp.169-176
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• 2010

The hyperosmotic stimulus is regarded as a mechanical factor for bone remodeling. However, whether the hyperosmotic stimulus affects $1{\alpha}$, 25-dihydroxyvitamin $D_3$ ($1{\alpha},25(OH)_2D_3$)-induced osteoclastogenesis is not clear. In the present study, the effect of the hyperosmotic stimulus on $1{\alpha},25(OH)_2D_3$-induced osteoclastogenesis was investigated in an osteoblast-preosteoclast co-culture system. Serial doses of sucrose were applied as a mechanical force. These hyperosmotic stimuli significantly evoked a reduced number of $1{\alpha},25(OH)_2D_3$-induced tartrate-resistant acid phosphatase-positive multinucleated cells and $1{\alpha},25(OH)_2D_3$-induced bone-resorbing pit area in a co-culture system. In osteoblastic cells, receptor activator of nuclear factor ${\kappa}B$ ligand (RANKL) and Runx2 expressions were down-regulated in response to $1{\alpha},25(OH)_2D_3$. Knockdown of Runx2 inhibited $1{\alpha},25(OH)_2D_3$-induced RANKL expression in osteoblastic cells. Finally, the hyperosmotic stimulus induced the overexpression of TonEBP in osteoblastic cells. These results suggest that hyperosmolarity leads to the down-regulation of $1{\alpha},25(OH)_2D_3$-induced osteoclastogenesis, suppressing Runx2 and RANKL expression due to the TonEBP overexpression in osteoblastic cells.

• International Journal of Oral Biology
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• 제41권4호
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• pp.253-262
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• 2016

Streptococcus mutans (S. mutans) is one of the most important bacteria in the formation of dental plaque and dental caries. S. mutans adheres to an acquired pellicle formed on the tooth surface, and aggregates with many oral bacteria. It initiates plaque formation by synthesizing glucan from sucrose, which is catalyzed by glucosyltransferases. Propolis is a resinous mixture produced by honeybees, by mixing saliva and beeswax with secretions gathered from wood sap and flower pollen. Bees prevent pathogenic invasions by coating the propolis to the outer and inner surface of the honeycomb. Propolis has traditionally been used for the treatment of allergic rhinitis, asthma and dermatitis. We investigated the inhibitory effects of propolis ethanol extract on biofilm formation and gene expression of S. mutans. The biofilm formation of S. mutans was determined by scanning electron microscopy (SEM) and safranin staining. We observed that the extract of propolis had an inhibitory effect on the formation of S. mutans biofilms at concentrations higher than 0.2 mg/ml. Real-time PCR analysis showed that the gene expression of biofilm formation, such as gbpB, spaP, brpA, relA and vicR of S. mutans, was significantly decreased in a dose dependent manner. The ethanol extract of propolis showed concentration dependent growth inhibition of S. mutans, and significant inhibition of acid production at concentrations of 0.025, 0.05, 0.1 and 0.2 mg/ml, compared to the control group. These results suggest that the ethanol extract of propolis inhibits gene expression related to biofilm formation in S. mutans.

• Journal of Dental Anesthesia and Pain Medicine
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• 제18권4호
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• pp.223-233
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• 2018

Topical anesthetics are commonly used in oral & maxillofacial surgery to control pain in the oral cavity mucosa before local anesthetic injection. These anesthetic agents come in many forms, developed for different usages, to minimize adverse reactions, and for optimal anesthetic efficiency. Earlier studies have revealed that these agents may also limit the growth of microorganisms in the area of anesthetic application. Many topical anesthetic agents show different levels of antimicrobial activity against various bacterial strains and Candida. The dosage of local anesthetic agent used in some clinical preparations is too low to show a significant effect on microbial activity. Efficiency of antimicrobial activity depends on the local anesthetic agent's properties of diffusion within the bloodstream and binding efficiency with cytoplasmic membrane, which is followed by disruption of the bacterial cell membrane. The antimicrobial properties of these agents may extend their usage in patients to both control pain and infection. To develop the topical local anesthetic optimal usage and antimicrobial effect, a collaborating antiseptic agent may be used to benefit the local anesthetic. However, more research is required regarding minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of topical local anesthetic agents with drug interaction between anesthetics and antiseptic agents.

• International Journal of Oral Biology
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• 제45권4호
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• pp.204-210
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• 2020

Excessive intake of sodium caused by high salt diet promotes the expression of inflammatory cytokines and differentiation of helper T cells resulting in inflammatory responses. High-glucose diet also contributes to the pathogenesis of periodontitis by inducing changes in the oral microbiome and reducing salivation. However, the effect of a high-salt and glucose diet (HSGD) on the prognosis of periodontitis remains unclear. In this study, a rat model of experimental periodontitis was established by periodic insertion of absorbable sutures containing Porphyromonas gingivalis and Fusobacterium nucleatum strains into the right gingival sulcus to analyze the effect of HSGD on the incidence and progression of periodontitis. The alveolar bone heights (ABH) was measured with microcomputed tomography imaging of the HSGD- and general diet (GD)-treated groups. The right ABH was significantly decreased compared to the left in both groups at 4 weeks after induction of inflammation; however, no significant difference was noted between the groups. Notably, the ABH in the HSGD-treated group was significantly decreased at 8 weeks after induction of inflammation, whereas in the GD-treated group, an increase in the ABH was observed; a significant difference of the ABH was noted between the two groups (p < 0.05). At 12 weeks, recovery of the alveolar bone was observed in both groups, with no significant differences in ABH between the two groups. These findings indicate that the intake of excessive sodium attenuates the recovery rate of the alveolar bone even after the local infectant is removed. In addition, this study demonstrates the use of HSGD in establishing a new animal model of periodontitis.

• 한국치위생학회지
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• 제19권3호
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• pp.387-397
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• 2019

Objectives: This study was conducted to examine the subjects' oral health status and changes in the oral environment after mouthwash with effervescent Vitamin C and its intake and to understand the impact on changes in the number of bacteria causing periodontal diseases in the oral cavity based on the oral health status and oral environmental condition. Methods: After obtaining approval from the Institutional Review Board of D-University, 45 people (24 in an experimental group and 21 in a control group) who participated in the oral health program were selected, among visitors of the Clinical Dental Hygienics Laboratory of D. University in B. Results: Based on the subjects' periodontal health status, the number of bacteria causing periodontal diseases in the oral cavity decreased in both experimental and control groups before and after the experiment. However, in the experimental group, it was significant when the Bleeding on Probing(BOP) level was below average, and Calculus index(CAL) was above average, in Aggregatibacter actinomycetemcomitans and the red complex. It was also significant when CAL was above average in the orange complex in the control group. Regarding bacterial changes in periodontal diseases based on the subjects' oral environmental condition, there was a significant change in the Adenosine Tri Phosphate (ATP : intraoral contaminants test) test in the oral cavity in A. actinomycetemcomitans and the red complex in the experimental group and in the O'Leary index in the control group. Further, there was a significant change in the orange complex in the ATP test in the experimental group. Conclusions: A comprehensive analysis of the results revealed that the oral health care program for dental hygiene decreased the number of bacteria causing periodontal diseases in the oral cavity in both experimental and control groups.