Yuka Hiroshima

The University of Tokushima, Tokusima, Tokushima, Japan

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Publications (17)38.09 Total impact

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    ABSTRACT: Amorphous calcification frequently appears in dental pulp tissues of diabetic patients; however, its pathologic process has not been fully elucidated. We previously found that pulp stones and thickened predentin occurred more frequently in diabetic rats. Recent findings demonstrated that accumulation of advanced glycation end-products (AGE) might be involved in vascular calcification complicated with diabetes. The aim of this study was to determine the effect of AGE on calcified nodule formation by rat dental pulp cells in culture. Rat dental pulp cells and gingival fibroblasts were independently cultured with 50 and 100 μg/mL AGE. Alkaline phosphatase activity and calcified nodule formation were measured. Expressions of receptor for AGE, osteopontin (OPN), and osteocalcin (OCN) mRNA were determined by quantitative real-time polymerase chain reaction. Protein levels of OPN and OCN secreted in culture medium were quantified by enzyme-linked immunosorbent assay. AGE (50 and 100 μg/mL) markedly increased both alkaline phosphatase activity and calcified nodule formation in dental pulp cells (P < .01), whereas it did not affect those in gingival fibroblasts. Real-time polymerase chain reaction analysis revealed that AGE increased mRNA expressions of receptor for AGE, OPN, and OCN in dental pulp cells (P < .05). Enzyme-linked immunosorbent assay analysis revealed that the protein levels of OPN and OCN produced by dental pulp cells were higher in AGE-treated than in untreated cells (P < .05). AGE enhanced the calcification potentials of rat dental pulp cells, suggesting that it may stimulate pathologic calcification of diabetic dental pulp tissues.
    Journal of endodontics 07/2013; 39(7):873-8. · 2.95 Impact Factor
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    ABSTRACT: S100A9 is a calcium-binding protein and subunit of antimicrobial calprotectin complex (S100A8/A9). Produced by neutrophils, monocytes/ macrophages and keratinocytes, S100A9 expression increases in response to inflammation. For example, IL-1α produced by epithelial cells acts autonomously on the same cells to induce expression of S100A8/A9 and cellular differentiation. Whereas it is well known that IL-1α and members of the IL-10 family of cytokines upregulate S100A8 and S100A9 in several cell lineages, the pathway and mechanism of IL-1α-dependent transcriptional control of S100A9 in epithelial cells is not established. Modeled using human epidermal keratinocytes (HaCaT cells), IL-1α stimulated phosphorylation of p38 MAPK and induced S100A9 expression, which was blocked by IL-1 receptor antagonist, RNAi suppression of p38, or a p38 MAPK inhibitor. Transcription of S100A9 in HaCaT cells depended on nucleotides -94 to -53 in the upstream promoter region, based upon use of deletion constructs and luciferase reporter activity. Within the responsive promoter region, IL-1α increased the binding activity of CCAAT/enhancer binding protein β (C/EBPβ. Mutated C/EBPβ binding sequences or C/EBPβ-specific siRNA inhibited the S100A9 transcriptional response. Hence, IL-1α is strongly suggested to increase S100A9 expression in a human epidermal keratinocyte cell line by signaling through the IL-1 receptor and p38 MAPK, increasing C/EBPβ-dependent transcriptional activity.
    Biochimica et Biophysica Acta 04/2013; · 4.66 Impact Factor
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    Odontology 01/2013; · 1.58 Impact Factor
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    ABSTRACT: Sandwich enzyme-linked immunosorbant assay (ELISA) using a 96-well plate is frequently employed for clinical diagnosis, but is time-and sample-consuming. To overcome these drawbacks, we performed a sandwich ELISA on a microchip. The microchip was made of cyclic olefin copolymer with 4 straight microchannels. For the construction of the sandwich ELISA for interleukin-6 (IL-6) or tumor necrosis factor-α (TNF-α), we used a piezoelectric inkjet printing system for the deposition and fixation of the 1st anti-IL-6 antibody or 1st anti-TNF-α antibody on the surface of the each microchannel. After the infusion of 2 µl of sample to the microchannel and a 20 min incubation, 2 µl of biotinylated 2nd antibody for either antigen was infused and a 10 min incubation. Then 2 µl of avidin-horseradish peroxidase was infused; and after a 5 min incubation, the substrate for peroxidase was infused, and the luminescence intensity was measured. Calibration curves were obtained between the concentration and luminescence intensity over the range of 0 to 32 pg/ml (IL-6: R(2) = 0.9994, TNF-α: R(2) = 0.9977), and the detection limit for each protein was 0.28 pg/ml and 0.46 pg/ml, respectively. Blood IL-6 and TNF-α concentrations of 5 subjects estimated from the microchip data were compared with results obtained by the conventional method, good correlations were observed between the methods according to linear regression analysis (IL-6: R(2) = 0.9954, TNF-α: R(2) = 0.9928). The reproducibility of the presented assay for the determination of the blood IL-6 and TNF-α concentration was comparable to that obtained with the 96-well plate. Simultaneous detection of blood IL-6 and TNF-α was possible by the deposition and fixation of each 1st antibody on the surface of a separate microchannel. This assay enabled us to determine simultaneously blood IL-6 and TNF-α with accuracy, satisfactory sensitivity, time saving ability, and low consumption of sample and reagents, and will be applicable to clinic diagnosis.
    PLoS ONE 01/2013; 8(1):e53620. · 3.73 Impact Factor
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    ABSTRACT: This study aimed to analyze the enzyme activity in gingival crevicular fluid (GCF) and its association with clinical parameters, especially bleeding on probing (BOP), and thus reconsider the significance and accuracy of recording BOP. A total of 184 patients who had entered supportive periodontal therapy were selected and GCF was collected from 401 sites before recording the clinical parameters, probing pocket depth (PPD), BOP, clinical attachment level, gingival index and plaque index. The enzyme activity of neutrophil elastase and aspartate aminotransferase and amount of protein in GCF were also analyzed. In the clinical parameters for biochemical data, amount of GCF showed the most correlation. A cut-off value for BOP and PPD were determined by the ROC curve and Youden index. Analysis was performed with all clinical parameters and biochemical data. Of the 401 sites, 51 were less than the cut-off value and were BOP-negative. On the other hand, 29 sites had values more than the cut-off value, with 14 BOP-negative sites and 15 BOP-positive sites. A conclusion is as follows: twenty-nine sites with values more than the cut-off value were diagnosed as sites requiring periodontal management, however, 14 of these were BOP-negative. These results suggest that combining other biochemical tests with examination of BOP and PPD may improve the validity of periodontal disease diagnosis. In future studies, it will be essential to find a marker that can precisely detect periodontal disease activity, and to develop a diagnostic tool for chair-side use.
    Odontology 11/2012; · 1.58 Impact Factor
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    ABSTRACT: Gingival crevicular fluid (GCF) contains calprotectin, which appears to be a useful biomarker for periodontal diseases because of its high level in GCF from periodontally diseased pockets. To determine calprotectin in GCF that has a very small volume, sandwich enzyme-linked immunosorbent assay (ELISA) on a microchip was performed and its utility was estimated. Anti-calprotectin primary antibody was discharged on a microchip using a piezoelectric inkjet printing system. Calprotectin standard and calprotectin in GCF samples from eleven subjects were determined by the ELISA method with the prepared microchip and their values were compared with those obtained by conventional ELISA. Using the ELISA on a microchip, a reasonable standard curve of calprotectin protein (1.56-100ng/mL) was obtained. Calprotectin in GCF samples was quantified and showed reasonable values in accordance with the condition of periodontal diseases. The values determined by the microchip method and conventional ELISA showed a significant linear relationship (R(2)=0.981). Calprotectin in GCF was determined using the ELISA on a microchip with high efficiency and this ELISA method for calprotectin determination may become a useful method for diagnosing periodontal diseases.
    Clinical biochemistry 05/2012; 45(15):1239-44. · 2.02 Impact Factor
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    ABSTRACT: Resistin is an adipocytokine that induces insulin resistance and is predominantly expressed in adipocytes and peripheral blood mononuclear cells. Resistin expression increases in inflammatory diseases as well as diabetes mellitus, and is upregulated by bacterial pathogens and proinflammatory cytokines. The aim of this study was to identify resistin in human gingival crevicular fluid, to compare the resistin levels in gingival crevicular fluid between subjects with and without periodontitis and diabetes mellitus and to investigate the regulation of resistin release from human neutrophils by Porphyromonas gingivalis lipopolysaccharide (P-LPS). Gingival crevicular fluid samples were collected from patients with chronic periodontitis (n = 24), patients with diabetes mellitus-related periodontitis (n = 18) and healthy subjects (n = 21). Resistin in gingival crevicular fluid was determined using western blot analysis and an ELISA kit. The glycated hemoglobin (HbA(1c)) value was obtained from patients with diabetes mellitus-related periodontitis by a medical interview. Human neutrophils were cultured with P-LPS (0-1000 ng/mL), or incubated with inhibitors of actin or microtubule polymerization in the absence or presence of P-LPS. The medium and cellular fractions were used for determination of resistin by ELISA. The resistin level in gingival crevicular fluid from patients with periodontitis or diabetes mellitus-related periodontitis was significantly higher than that of healthy subjects. The resistin level in gingival crevicular fluid was correlated with gingival index score, but not blood HbA(1c) value. The P-LPS increased resistin release from human neutrophils, and its induction was decreased by actin polymerization inhibitors. We show, for the first time, the presence of resistin in gingival crevicular fluid. A high resistin level in gingival crevicular fluid samples from periodontitis patients may to some extent be related to P-LPS-induced resistin release from neutrophils.
    Journal of Periodontal Research 02/2012; 47(5):554-62. · 1.99 Impact Factor
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    ABSTRACT: Gingival crevicular fluid is a bodily fluid transuded from periodontal tissues into the gingival crevice and periodontal pocket, and contains many species of components. Proteins in gingival crevicular fluid have been studied as markers for periodontal diseases. Mass spectrometric analysis is used for the analyses of proteins, lipids, saccharides and metals, and expected as an approach for disease diagnosis. For better analysis of the protein components in gingival crevicular fluid, we investigated proteins in gingival crevicular fluid samples from the healthy gingival crevice and periodontal pocket using mass spectrometry. Gingival crevicular fluid samples were collected from subjects who gave their informed consent and were periodontally healthy or had diseased pockets. These samples were electrophoretically separated, and each fraction on the gels was analysed by nano liquid chromatography coupled with tandem mass spectrometry. Antimicrobial peptides detected in gingival crevicular fluid were confirmed by western blotting. One hundred and four proteins were detected in gingival crevicular fluid samples from both healthy sites and sites of periodontitis; 64 proteins were contained only in gingival crevicular fluid from healthy sites and 63 proteins were observed only in gingival crevicular fluid from periodontitis sites. These proteins were blood-, cytoskeleton-, immunity-, inflammation- and lipid-related proteins and enzymes. Some proteins, including ceruloplasmin, glycogen phosphorylase, glutathione S-transferase, phosphoglycerate mutase, psoriasin, S100A11 and resistin, were identified for the first time in gingival crevicular fluid. Antimicrobial peptides, such as lactoferrin, α1-antitrypsin, lipocalin, S100A7, S100A8, S100A9 and cathelicidin, were observed by mass spectrometry and western blotting. Multiple protein components in gingival crevicular fluid were analysed at the same time using mass spectrometry, and this approach may be useful for the diagnosis of periodontal diseases.
    Journal of Periodontal Research 01/2012; 47(4):488-99. · 1.99 Impact Factor
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    ABSTRACT: In the oral cavity, mucosal keratinocytes resist bacterial infection, in part, by producing broad-spectrum antimicrobial peptides (AMPs) including defensin, adrenomedullin and calprotectin. Epidermal keratinocyte expression of many AMPs increases in response to interleukin-1α (IL-1α). IL-1α is produced by epidermal keratinocytes and regulates cell differentiation. To better understand innate immunity in the oral cavity, we sought to determine how IL-1α might regulate expression of AMPs by human gingival keratinocytes (HGKs) using DNA microarray and Western blot analyses. HGKs from three subjects expressed eleven AMPs, including S100A7, S100A8, S100A9, S100A12, secretory leucocyte protease inhibitor, lipocalin 2 (LCN2), cystatin C and β-defensin 2. Of the expressed AMPs, S100A7, S100A12 and LCN2 were up-regulated by IL-1α (inducible AMPs); the other AMPs were considered to be constitutive. Human gingival keratinocytes, therefore, express constitutive and IL-1α-inducible AMPs to provide a rapid and robust innate response to microbial infection.
    Archives of oral biology 02/2011; 56(8):761-7. · 1.65 Impact Factor
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    ABSTRACT: S100A8 and S100A9 constitute a heterodimeric protein, calprotectin. The mRNAs of S100A8 and S100A9, being expressed at minimal levels in the submandibular and parotid glands (SMG and PG, respectively) of C3H/HeN mice, were induced strongly and transiently by lipopolysaccharide (LPS). Among the mRNAs of members of the S100 protein family examined, those of S100A8 and S100A9 were specifically induced by LPS in the salivary glands. The induction was assumed to be mediated via toll-like receptor 4 (TLR4), since their elevation was limited in C3H/HeJ mice, a TLR4-mutant strain. These proteins became expressed in the granular convoluted tubular cells and striated duct cells in the SMG, and in both acinar and duct cells in the PG (all in the cytoplasm). The salivary calprotectin level was not increased by LPS treatment, implying that elevated calprotectin was not secreted into the saliva and that they may function in microcellular environment of the salivary gland.
    Inflammation 12/2010; 34(6):668-80. · 2.46 Impact Factor
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    ABSTRACT: Chorda tympani denervation (CTD) of rats was earlier shown to result in loss of submandibular gland (SMG) weight (at only 1 wk) and in continued reduction in aquaporin 5 (AQP5) protein expression (until 4 wk), without affecting its mRNA synthesis (Li X, Azlina A, Karabasil MR, Purwanti N, Hasegawa T, Yao C, Akamatsu T, Hosoi K. Am J Physiol Gastrointest Liver Physiol 295: G112-G123, 2008). The present study indicated that despite elevation of bax, a proapoptosis protein, by CTD, the operation also increased the level of bcl-2, an antiapoptosis protein, in the SMG. Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL assay) showed no increase in the number of apoptotic cells in the SMG. CTD, however, induced strongly and transiently (at 1-3 days) the protein expression of LC3B-II, a marker protein of autophagosomes, suggesting that the reduction in the gland weight was due to onset of autophagy by CTD. Upon CTD, Lamp2, a lysosomal marker, gradually increased in amount, reaching a peak at the 14th day. Immunohistochemical analysis revealed an increase in the number of lysosome-like structures positive for both AQP5 and Lamp2 in the acinar cells of the SMG after CTD; similar changes were observed also for AQP5 and LC3Bs. These data suggest that AQP5 in the SMG entered autophagosomes and/or lysosomes for degradation upon CTD. In vitro AQP5-degrading activity was found in the SMG extracts, and such activity was shown to be increased by CTD. Inhibitor experiments implied cathepsins B and L to be candidate enzymes for this degradation under normal and CTD conditions, respectively.
    AJP Gastrointestinal and Liver Physiology 11/2010; 299(5):G1106-17. · 3.65 Impact Factor
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    ABSTRACT: Calprotectin is an antimicrobial complex composed of the S100A8 and S100A9 protein family subunits. Contributing to innate immunity, calprotectin expression is increased by interleukin-1alpha (IL-1alpha), which modulates keratinocyte differentiation. Keratinocyte growth factor (KGF) is produced by mesenchymal cells and has a mitogenic activity for epithelial cells. In this study, we investigated the effect of KGF on calprotectin expression in keratinocytes and modulation by IL-1alpha. Human keratinocytes were cultured with KGF in the presence or absence of a KGF receptor (KGFR) inhibitor or mitogen-activated protein kinase (MAPK) inhibitors. Calprotectin (S100A8/S100A9) expression was determined by northern blotting and enzyme-linked immunosorbent assay, respectively, whereas MAPK phosphorylation was analyzed by western blot analysis. KGF significantly decreased the expression of S100A8/S100A9-specific mRNAs and calprotectin protein. In the presence of KGF, KGFR inhibitor or extracellular-regulated kinase inhibitor restored KGF-downregulated expression of S100A8/S100A9. KGF increased IL-1alpha expression in keratinocytes, whereas IL-1alpha increased KGF expression in fibroblasts. Cocultured fibroblast and keratinocytes showed lower S100A8/S100A9 mRNA expression than keratinocytes alone in the presence or absence of IL-1alpha or KGF. These results suggest that fibroblast-derived KGF reduces or restricts calprotectin expression in keratinocytes, which supports our hypothesis that calprotectin expression in keratinocytes is modulated by factors associated with epithelial-mesenchymal interactions.
    Immunology and Cell Biology 01/2010; 88(3):328-33. · 3.93 Impact Factor
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    ABSTRACT: Oral epithelial cells help to prevent against bacterial infection in the oral cavity by producing antimicrobial peptides (AMPs). A broad-spectrum AMP, calprotectin (a complex of S100A8 and S100A9 proteins), is expressed by oral epithelial cells and is up-regulated by interleukin-1alpha (IL-1alpha). Shosaikoto (SST) is a traditional Japanese herbal medicine that has immunomodulatory effects and is reported to enhance the levels of IL-1alpha in epithelial cells. The purpose of this study was to investigate the effect of SST on the expression of calprotectin and other AMPs through the regulation of IL-1alpha in oral epithelial cells. Human oral epithelial cells (TR146) were cultured with SST (at concentrations ranging from 10 to 250 microg/mL) in the presence or absence of anti-IL-1alpha or IL-1 receptor antagonist. The expression of S100A8- and S100A9-specific mRNAs was examined by northern blotting. Calprotectin expression and IL-1alpha secretion were investigated by immunofluorescent staining or ELISA. The expression of other AMPs and IL-1alpha was analyzed by RT-PCR and by quantitative real-time PCR. Shosaikoto (25 microg/mL) significantly increased the expression of S100A8- and S100A9-specific mRNAs and calprotectin protein. Shosaikoto increased S100A7 expression, but had no effect on the expression of other AMPs. The expression of IL-1alpha-specific mRNA and its protein were slightly increased by SST. A neutralizing antibody against IL-1alpha or IL-1 receptor antagonist inhibited SST up-regulated S100A8/S100A9 mRNA expression. These results suggest that SST increases the expression of calprotectin and S100A7 in oral epithelial cells. In response to SST, up-regulation of calprotectin may be partially induced via IL-1alpha.
    Journal of Periodontal Research 08/2009; 45(1):79-86. · 1.99 Impact Factor
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    ABSTRACT: Calprotectin is a major cytosolic calcium-binding protein of leukocytes which belongs to the S100 protein family. S100A8 and S100A9, major types of calprotectin are heterodimeric complexes being composed of light- and heavy-chain subunits. The calprotectin levels in the plasma, feces, synovial fluid, gingival crevicular fluid, dental calculus and saliva change when the host animal suffers from several inflammatory diseases. Members of Toll-like receptor (TLR) family are pattern-recognition receptors for lipopolysaccharide (LPS) and other pathogens. Here we examined if the biological role of TLR receptor is reflected to the calprotectin expression in the salivary gland. Time course study by using real-time RT-PCR detected higher levels of S100A8 and S100A9 mRNA at 1.5-3 h after injection of LPS in both the submandibular gland (SMG) and parotid gland (PG) of C3H/HeN mice but not in the same tissues of C3H/HeJ, a TLR-4 mutant strain, indicating that this induction is mediated via the TLR-4. These results indicate that, an inflammatory marker, calprotectin, is expressed in the mouse salivary gland and that LPS stimulated its synthesis. Calprotectin (S100A8/A9) showed minimum expression in all cellular segments in the SMG except excretory duct cells, which showed strong signal at the cytoplasm. LPS induced their expressions in the granular convoluted tubular cells and striated duct cells. In the PG, these proteins were expressed very weakly in both duct and acinar cells with a little stronger staining for the former cells. LPS injection induced calprotectin (S100A8/A9) in both duct and acinar cells especially in the former cells.
    The Journal of Medical Investigation 01/2009; 56 Suppl:287-9.
  • Jun-Ichi Kido, Mami Hino, Mika Bando, Yuka Hiroshima
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    ABSTRACT: Many middle aged and old persons take periodontal diseases that mainly cause teeth loss and result in some systemic diseases. The prevention of periodontal diseases is very important for oral and systemic health, but the present diagnostic examination is not fully objective and suitable. To diagnose periodontal diseases exactly, some biomarkers shown inflammation, tissue degradation and bone resorption, in gingival crevicular fluid (GCF) and saliva are known. We demonstrated that GCF levels of calprotectin, inflammation-related protein, and carboxy-terminal propeptide of type I procollagen, bone metabolism-related protein, were associated with clinical condition of periodontal diseases, and suggested that these proteins may be useful biomarkers for periodontal diseases. Recently, determinations of genes and proteins by using microdevices are studied for diagnosis of some diseases. We detected calprotectin protein by chemiluminescent immunoassay on a microchip and showed the possibility of specific and quantitative detection of calprotectin in a very small amount of GCF. To determine plural markers in GCF by using microdevices contributes to develop accurate, objective diagnostic system of periodontal diseases.
    IEEJ Transactions on Electronics Information and Systems 01/2009; 129(2):233-237.
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    ABSTRACT: Human epidermis and epithelium serve as physiologic barriers to protect against noxious and infectious agents. Contributing to the defense against infection, epithelial cells express antimicrobial peptides (AMPs). The expression of AMPs in keratinocytes is generally regulated directly by bacteria and indirectly by proinflammatory cytokines. Bacteria may also regulate AMP expression by inducing keratinocyte expression of the autonomous proinflammatory cytokine, interleukin-1alpha (IL-1alpha). To test the hypothesis that AMP expression may be regulated by cell autonomous cytokines, we investigated the effect of IL-1alpha on the expression of AMPs in human keratinocytes (HaCaT cells) by microarray, northern blot, reverse transcriptase (RT)-PCR and western blot analyses. IL-1alpha increased expression of mRNA in a dose- and time-dependent manner specific for lipocalin 2, S100A8, S100A9 and secretory leukocyte protease inhibitor (SLPI) more than twofold relative to nonstimulated cells (control), and slightly upregulated S100A7 and beta-defensin-2. Furthermore, the expression of lipocalin 2, S100A7, S100A8, S100A9 and SLPI proteins were upregulated by IL-1alpha. On the other hand, HaCaT cells expressed mRNA specific for other AMPs, including cystatin 3, adrenomedullin, RNase-7 and mucin 5, which were unaffected by IL-1alpha treatment. These results suggest that the autonomous keratinocyte cytokine, IL-1alpha, selectively upregulates the expression of AMPs which may modulate innate epithelial cell immunity in skin and mucosa.
    Immunology and Cell Biology 11/2007; 85(7):532-7. · 3.93 Impact Factor
  • Nihon Shishubyo Gakkai Kaishi (Journal of the Japanese Society of Periodontology) 01/2007; 49(3):224-232.

Publication Stats

69 Citations
38.09 Total Impact Points


  • 2013
    • The University of Tokushima
      • Department of Periodontology and Endodontology
      Tokusima, Tokushima, Japan
  • 2012–2013
    • The Nippon Dental University
      • Department of Periodontology
      Tokyo, Tokyo-to, Japan