Publications (19)38.53 Total impact
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Article: Nephronectin expression is regulated by SMAD signaling in osteoblast-like MC3T3-E1 cells.
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ABSTRACT: Nephronectin (Npnt) is an extracellular matrix protein known to be a ligand for the integrin α8β1. We previously demonstrated that Npnt expression was suppressed by TGF-β through ERK1/2 and JNK in osteoblasts. In this study, we found that inhibition of a TGF-β type I receptor (TGF-β R1, Alk5) by a specific inhibitor {2-[3-(6-Methylpyridin-2-yl)-1H-pyrazol-4-yl]-1,5-naphthyridine} strongly induced Npnt expression in osteoblast-like MC3T3-E1 cells. The Alk5 inhibitor-induced increase of Npnt expression occurred in both time- and dose-dependent manners, while that expression was also induced by introduction of an siRNA for Smad2, a central intracellular mediator of TGF-β signaling. These results suggest that the expression of Npnt is regulated by the Alk5-SMAD signaling pathway in osteoblasts.Biochemical and Biophysical Research Communications 07/2012; 425(2):390-2. · 2.48 Impact Factor -
Article: BMP2 differentially regulates the expression of Gremlin1 and Gremlin2, the negative regulators of BMP function, during osteoblast differentiation.
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ABSTRACT: Bone morphogenetic proteins (BMPs) control the expressions of many genes involved in bone formation. On the basis of our hypothesis that BMP2 stimulation-regulated gene expression plays a critical role in osteoblast differentiation, we performed genome-wide screening of messenger RNA from BMP2-treated and -untreated C2C12 cells using a DNA microarray technique. We found that the expressions of Gremlin1 and Gremlin2, which are known BMP antagonists, were bidirectionally regulated by BMP2. Gremlin1 was down-regulated by BMP2, while Gremlin2 was up-regulated in both time- and dose-dependent manners. Ablation of Gremlin1 or Gremlin2 enhanced osteoblast differentiation induced by BMP2. On the other hand, treatment with recombinant Gremlin1 inhibited BMP2-induced osteoblast differentiation. Furthermore, treatment with Smad4 siRNA and the p38 MAPK inhibitor SB203580 suppressed BMP2-induced Gremlin2 gene expression. The differential regulation of Gremlin1 and Gremlin2 gene expressions by BMP2 may explain the critical function of these genes during osteoblast differentiation.Calcified Tissue International 05/2012; 91(1):88-96. · 2.38 Impact Factor -
Article: Cdc42 is required for chondrogenesis and interdigital programmed cell death during limb development.
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ABSTRACT: Cdc42, a member of the Rho subfamily of small GTPases, is known to be a regulator of multiple cellular functions, including cytoskeletal organization, cell migration, proliferation, and apoptosis. However, its tissue-specific roles, especially in mammalian limb development, remain unclear. To investigate the physiological function of Cdc42 during limb development, we generated limb bud mesenchyme-specific inactivated Cdc42 (Cdc42(fl/fl); Prx1-Cre) mice. Cdc42(fl/fl); Prx1-Cre mice demonstrated short limbs and body, abnormal calcification of the cranium, cleft palate, disruption of the xiphoid process, and syndactyly. Severe defects were also found in long bone growth plate cartilage, characterized by loss of columnar organization of chondrocytes, and thickening and massive accumulation of hypertrophic chondrocytes, resulting in delayed endochondral bone formation associated with reduced bone growth. In situ hybridization analysis revealed that expressions of Col10 and Mmp13 were reduced in non-resorbed hypertrophic cartilage, indicating that deletion of Cdc42 inhibited their terminal differentiation. Syndactyly in Cdc42(fl/fl); Prx1-Cre mice was caused by fusion of metacarpals and a failure of interdigital programmed cell death (ID-PCD). Whole mount in situ hybridization analysis of limb buds showed that the expression patterns of Sox9 were ectopic, while those of Bmp2, Msx1, and Msx2, known to promote apoptosis in the interdigital mesenchyme, were down-regulated. These results demonstrate that Cdc42 is essential for chondrogenesis and ID-PCD during limb development.Mechanisms of development 02/2012; 129(1-4):38-50. · 2.83 Impact Factor -
Chapter: Interdisciplinary Treatment of Aggressive Periodontitis: Three-Dimensional Cone-Beam X-Ray Computed Tomography Evaluation
01/2012; , ISBN: 978-953-307-924-0 -
Article: Gene delivery system involving Bubble liposomes and ultrasound for the efficient in vivo delivery of genes into mouse tongue tissue.
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ABSTRACT: Oral squamous cell carcinoma is the most common type of head and neck cancer. Recently, efficient, easy, and minimally invasive gene delivery methods are expected to be developed as cancer gene therapies. However, the optimal method for delivering therapeutic genes into oral tissue for cancer treatment has not been elucidated. Therefore, we hypothesized that the tongue is a good target tissue for gene delivery with Bubble liposomes and ultrasound. To assess this, we attempted to deliver a mixture of plasmid DNA encoding a luciferase or enhanced green fluorescent protein, and Bubble liposomes into murine tongue with or without ultrasound exposure. The ultrasound conditions were 1 MHz, 2 W/cm(2), 60s, and duty cycle: 50%. The time-course of gene expression in the tongue was investigated with a luciferase assay and fluorescent microscopy. Luciferase expression was significantly increased in tongue transfected using Bubble liposomes and ultrasound compared with that of the tongue untreated with ultrasound, and this high level of luciferase activity was maintained for 2 weeks. From these results, Bubble liposomes can be used in combination with ultrasound to efficiently deliver plasmid DNA into the tongue in vivo. This technique is a highly promising approach for gene delivery into oral tissue.International journal of pharmaceutics 11/2011; 422(1-2):332-7. · 2.96 Impact Factor -
Article: Oxidized low-density lipoprotein-induced periodontal inflammation is associated with the up-regulation of cyclooxygenase-2 and microsomal prostaglandin synthase 1 in human gingival epithelial cells.
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ABSTRACT: Periodontitis is characterized by chronic gingival tissue inflammation, and inflammatory mediators such as IL-8 and prostaglandin E(2) (PGE(2)) are associated with disease progression. Previously we showed that oxidatively modified low-density lipoprotein (oxLDL) was present in gingival crevicular fluid. In this study, the role of oxLDL in the gingival epithelial cell inflammatory response was further investigated using Ca9-22 cells and primary human oral keratinocytes (HOK). Treatment of Ca9-22 cells and HOK with oxLDL induced an up-regulation of IL-8 and the PGE(2)-producing enzymes, cyclooxygenase-2 and microsomal PGE(2) synthase-1. These responses induced by oxLDL were significantly suppressed by a nuclear factor-kappa B (NF-κB) inhibitor. However, unlike the result in macrophages, oxLDL did not lead to an increase in CD36 expression in these two cells. These results suggest that oxLDL elicits gingival epithelial cell inflammatory responses through an activation of the NF-κB pathway. These data suggest a mechanistic link between periodontal disease and lipid metabolism-related disorders, including atherosclerosis.Biochemical and Biophysical Research Communications 09/2011; 413(4):566-71. · 2.48 Impact Factor -
Article: Expression of POEM, a positive regulator of osteoblast differentiation, is suppressed by TNF-α.
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ABSTRACT: POEM, also known as nephronectin, is an extracellular matrix protein considered to be a positive regulator of osteoblast differentiation. In the present study, we found that tumor necrosis factor-α (TNF-α), a key regulator of bone matrix properties and composition that also inhibits terminal osteoblast differentiation, strongly inhibited POEM expression in the mouse osteoblastic cell line MC3T3-E1. TNF-α-induced down-regulation of POEM gene expression occurred in both time- and dose-dependent manners through the nuclear factor kappa B (NF-κB) pathway. In addition, expressions of marker genes in differentiated osteoblasts were down-regulated by TNF-α in a manner consistent with our findings for POEM, while over-expression of POEM recovered TNF-α-induced inhibition of osteoblast differentiation. These results suggest that TNF-α inhibits POEM expression through the NF-κB signaling pathway and down-regulation of POEM influences the inhibition of osteoblast differentiation by TNF-α.Biochemical and Biophysical Research Communications 06/2011; 410(4):766-70. · 2.48 Impact Factor -
Article: Local gene delivery system by bubble liposomes and ultrasound exposure into joint synovium.
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ABSTRACT: Recently, we have developed novel polyethylene glycol modified liposomes (bubble liposomes; BL) entrapping an ultrasound (US) imaging gas, which can work as a gene delivery tool with US exposure. In this study, we investigated the usefulness of US-mediated gene transfer systems with BL into synoviocytes in vitro and joint synovium in vivo. Highly efficient gene transfer could be achieved in the cultured primary synoviocytes transfected with the combination of BL and US exposure, compared to treatment with plasmid DNA (pDNA) alone, pDNA plus BL, or pDNA plus US. When BL was injected into the knee joints of mice, and US exposure was applied transcutaneously to the injection site, highly efficient gene expression could be observed in the knee joint transfected with the combination of BL and US exposure, compared to treatment with pDNA alone, pDNA plus BL, or pDNA plus US. The localized and prolonged gene expression was also shown by an in vivo luciferase imaging system. Thus, this local gene delivery system into joint synovium using the combination of BL and US exposure may be an effective means for gene therapy in joint disorders.Journal of drug delivery. 01/2011; 2011:203986. -
Article: Docosahexaenoic acid induces adipose differentiation-related protein through activation of retinoid x receptor in human choriocarcinoma BeWo cells.
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ABSTRACT: Adipose differentiation-related protein (ADRP) is associated with intracellular lipid droplets that accumulate neutral lipids. Here we report that ADRP expression in a human choriocarcinoma cell line, BeWo, is regulated through activation of retinoid X receptor (RXR) and peroxisome proliferator-activated receptor-gamma (PPARgamma). Incubation with docosahexaenoic acid (DHA) or oleic acid (OA) induced accumulation of triacylglycerol (TG) and ADRP in BeWo cells. DHA-induced ADRP expression was suppressed by RXR-antagonists, PA452 and HX531. However, oleic acid-induced ADRP expression was not blocked by the RXR-antagonists but by a PPARgamma-antagonist. Treatment of the cells with RXR-agonists, HX630 and PA024, increased Adrp transcripts, however, they alone did not change the levels of ADRP protein and TG in BeWo cells. Induction of ADRP protein was observed in the presence of a proteasome inhibitor, suggesting that ADRP is degraded under lipid-poor conditions. These results suggest that expression of ADRP is in part regulated by RXR and PPARgamma transcription factors, and DHA induces ADRP by acting as an endogenous agonist of RXR.Biological & Pharmaceutical Bulletin 08/2009; 32(7):1177-82. · 1.66 Impact Factor -
Article: IFN-gamma down-regulates Secretoglobin 3A1 gene expression.
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ABSTRACT: STAT1 mediates Interferon (IFN)-dependent positive and negative regulation of inflammatory gene expression in lung. In this study, we examined the effect of IFN-gamma on the expression of SCGB3A1 which is thought to play crucial roles in inflammation and epithelial cell differentiation in lung. We found that expression of SCGB3A1 was down-regulated by IFN-gamma in a time- and dose-dependent manner in the murine transformed Clara Cells (mtCC) line. IFN-gamma induced the phosphorylation of STAT1, which binds to a STAT-binding element (SBE) in the SCGB3A1 gene promoter, leading to decreased transcriptional activation of this gene.Biochemical and Biophysical Research Communications 02/2009; 379(4):964-8. · 2.48 Impact Factor -
Chapter: Statin decreases IL-1 and LPS-induced inflammatory cytokines production in oral epithelial cells
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ABSTRACT: Periodontitis is a choronic inflammatory disease associated with degradation of periodontal tissues. This disease is considered to result of production of proinflammatory cytokines and tissue degradative enzymes which are initiated and advanced by lipopolysaccharide (LPS) of oral bacteria. Statin, 3-hydroxy-3-mrthylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, is known as a drug lowering serum cholesterol. In hyperlipidemia, the increase of cholesterol develops atherosclerosis in blood vessel. Many studies revealed that statins also have the cholesterol-independent, also termed pleiotropic, effects on variety of vascular cells, and decrease the expression level of inflammatory cytokines such as interleukin (IL)-l, IL-6 and IL-8. As a chronic inflammatory disease, periodontitis shares similar mechanisms with atherosclerosis. We measured the effect of simvastatin, one of statins, on IL-1 and LPS-induced IL-6 and IL-8 production in oral epithelial cells. Simvastatin decreased expression of these inflammatory cytokines and promoter activity of downstream pathway. Our results suggested that statin might be helpful tool for periodontitis.12/2007: pages 125-131; -
Article: TGF-beta suppresses POEM expression through ERK1/2 and JNK in osteoblasts.
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ABSTRACT: POEM, also called nephronectin, is an extracellular matrix protein that is considered to play a critical role as an adhesion molecule in the development and functioning of various tissues, such as kidneys and bones. In the present study, we examined the molecular mechanism of POEM gene expression, and found that transforming growth factor-beta (TGF-beta) strongly inhibited POEM expression in the mouse osteoblastic cell line, MC3T3-E1. TGF-beta-induced decrease of POEM expression occurred in both time- and dose-dependent manners through the activation of TGF-beta receptor I and extracellular signal-regulated kinase/c-Jun N-terminal kinase pathways.FEBS Letters 12/2007; 581(27):5321-6. · 3.54 Impact Factor -
Article: Establishment of cell lines that exhibit pluripotency from miniature swine periodontal ligaments.
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ABSTRACT: The periodontal ligament (PDL) is a fibrous connective tissue composed of heterogeneous cell types, including PDL fibroblasts. It is not clear whether cells within the PDL fibroblast population retain the potency to differentiate into other cell types. In the present study, clonal cell lines, derived from Clawn miniature swine PDLs, were established by gene transfection for a human telomerase reverse transcriptase, and characterized. These cell lines, denoted TesPDL1-4, had PDL fibroblasts that showed fibroblastic morphology and expressed procollagen alpha1(I), osteopontin, periostin and alkaline phosphatase mRNA. Under the specific culture conditions, TesPDL3 cells also have the ability to express CD31, vascular endothelial cadherin, von Willebrand factor, osteocalcin, and to form extracellular mineralized nodules. Our data indicate that TesPDL3 cells have unique properties of expressing several phenotype of fibroblasts, vascular endothelial cells and osteoblasts in cultures.Archives of Oral Biology 11/2007; 52(10):1002-8. · 1.60 Impact Factor -
Article: Recombinant human growth/differentiation factor-5 (rhGDF-5) induced bone formation in murine calvariae.
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ABSTRACT: Growth/differentiation factor-5 (GDF-5), a member of the transforming growth factor-beta superfamily, shows a close structural relationship to bone morphogenetic proteins and plays crucial roles in skeletal morphogenesis. Recombinant human (rh) GDF-5 was reported as a suitable factor for enhancing healing in bone defect and inducing ectopic bone formation. The purpose of the present study was to investigate the mechanism of bone formation induced by rhGDF-5 in murine calvariae by radiological, histological and immunohistochemical methods. Cell proliferation was also examined in vitro. Cells including primary osteoblasts, periosteum cells and connective tissue fibroblasts were isolated enzymatically from neonatal murine calvariae or head skin. In the presence or absence of rhGDF-5, cell proliferation was estimated by tetrazolium reduction assay. To examine the mechanism of osteoinduction, rhGDF-5/atelocollagen (AC) composite or 0.01 N HCl/AC composite were injected into murine calvariae subcutaneously. Tissue was examined radiologically, histologically and immunohistochemically. In the presence of rhGDF-5, proliferation of primary osteoblasts, periosteum cells, and connective tissue fibroblasts was increased significantly in culture. Immunohistochemical observations showed cells at the site injected with rhGDF-5/AC displayed immunoreactivity for proliferating cell nuclear antigen (PCNA). Newly formed bone- and cartilage-like tissue contained chondrocyte osteocyte and osteoclastic cells, and were immunoreactive for both type I and II collagen. Exposure to GDF-5 promotes proliferation and differentiation of calvarial cells, which give rise to ectopic bone formation.Journal of Periodontal Research 05/2006; 41(2):140-7. · 1.69 Impact Factor -
Article: Gene transfer to corneal epithelium and keratocytes mediated by ultrasound with microbubbles.
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ABSTRACT: The cornea is an ideal organ for evaluating gene transfer because it can be treated noninvasively and monitored easily. The present study was performed to investigate the practical efficacy and safety of ultrasound (US) plus microbubble (MB)-mediated gene transfer to cornea. Cultured rabbit corneal epithelial (RC-1) cells were incubated in 24-well dishes with plasmid DNA having a green fluorescent protein (GFP) gene under a cytomegalovirus promoter. The cells were exposed to US under different intensities (1 MHz; power, 0.5 approximately 2 W/cm2; duration, 15-120 seconds; duty cycle, 20%-100%). The effect of simultaneous stimulation with MBs was also examined. Gene transfer was quantified by counting the number of GFP-positive cells under microscopy. Furthermore, in vivo gene transfer was examined by GFP plasmid injection into rabbit cornea and US exposure with MBs. In the in vitro study, DNA exposure alone could not transfer gene into cultured RC-1 cells; US enhanced gene transfer slightly. Coexposure with MBs significantly increased gene transfer efficiency. In the in vivo study, DNA injection alone could transfer the gene to a limited degree, but plasmid injection plus US with MBs strongly increased gene transfer efficiency without apparent tissue damage, and gene transfer was achieved two dimensionally. US with MBs greatly increases gene transfer to in vivo and in vitro corneal cells. This noninvasive gene transfer method may be a useful tool for clinical gene therapy.Investigative Ophthalmology & Visual Science 03/2006; 47(2):558-64. · 3.60 Impact Factor -
Article: A novel mutation of the cathepsin C gene in a thai family with Papillon-Lefevre syndrome.
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ABSTRACT: Papillon-Lefevre syndrome (PLS) is a rare autosomal recessive disorder characterized by palmar- plantar hyperkeratosis and rapid periodontal destruction of both primary and permanent dentitions. It has been shown that the disease is caused by cathepsin C gene (CTSC) mutation leading to the deficiency of cathepsin C enzymatic activity. This study demonstrates the clinical manifestations and CTSC mutational and enzymatic activity analyses in a 5-year-old Thai male PLS patient and his parents. Peripheral blood samples were obtained for genomic DNA isolation. All exons of the CTSC gene were amplified by polymerase chain reaction (PCR) using specific primers. Mutations were identified by DNA sequencing. Verification of the mutation was performed by digestion of PCR products by restriction endonucleases. The cathepsin C enzymatic activity was determined using the synthetic substrate glycyl- L-arginine-7-amino-4-methylcoumarin. The patient demonstrated classical characteristics of PLS, including hyperkeratotic skin lesions. By the age of 5, all of his primary teeth were extracted due to severe periodontal infection. The parents had no physical abnormalities. The periodontal examination revealed localized mild periodontal destruction. Sequence analysis showed a nucleotide change at position 90 from C >A (c.90C >A) which resulted in a change from cysteine residue to a premature stop codon at the amino acid position 30 in the exon 1. The HpyCH4V digestion revealed that the patient was homozygous, whereas both the father and mother were heterozygous carriers of this mutation. The cathepsin C activity was reduced in the patient's mother, and the activity in the patient was almost completely lost. This is the first study to demonstrate a CTSC gene mutation in a Thai family with PLS. The identified mutation is novel and potentially leads to the drastic reduction of the cathepsin C enzymatic activity. This suggests that the mutation is pathogenetic, causing the PLS. Mutational analysis in more members of the family is warranted to identify whether the mutation is inherited from a common ancestor.Journal of Periodontology 04/2005; 76(3):492-6. · 2.60 Impact Factor -
Article: Effects of growth/differentiation factor-5 on human periodontal ligament cells.
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ABSTRACT: Growth/differentiation factor-5 (GDF-5), a member of the transforming growth factor-beta superfamily, shows a close structural relationship to bone morphogenetic proteins and plays crucial roles in skeletal, tendon, and ligament morphogenesis. The mRNA encoding GDF-5 is also expressed during odontogenesis, especially in dental follicle tissue. While this suggests that GDF-5 participates in the formation of alveolar bone and the periodontal ligament, cementum, and dental root, the physiologic role of GDF-5 in these tissues in adulthood remains unclear. We therefore investigated GDF-5 effects upon cultures of human periodontal ligament (HPDL) cells. HPDL cells were obtained from healthy periodontal ligaments of individuals. Tetrazolium reduction assay was carried out for cell proliferation assay. Alkaline phosphatase (ALP) activity was estimated by measuring light absorbance at 405 nm. Reverse transcription-polymerase chain reaction (RT-PCR) and northern analysis were performed for gene expression in cultured HPDL cells. Sulfated glycosaminoglycan (sGAG) synthesis was evaluated by histochemical staining and a quantitative dye-binding method. Expression of GDF-5 and its receptor was demonstrated in HPDL cells by RT-PCR. ALP activity in HPDL cells was significantly decreased by addition of rhGDF-5 at 10-1000 ng/ml (p < 0.05). Although northern analysis showed little change in gene expression for collagen alpha2(I) in rhGDF-5-stimulated HPDL cells, rhGDF-5 dose-dependently enhanced cell proliferation. This proliferative effect persisted for 16 d. Alcian blue staining and dye-binding assays indicated that sGAG synthesis was enhanced by rhGDF-5. rhGDF-5 may provide an environment fostering periodontal healing or regeneration by affecting extracellular matrix metabolism.Journal of Periodontal Research 12/2003; 38(6):597-605. · 1.69 Impact Factor -
Article: Growth/differentiation factor-5 induces growth arrest and apoptosis in mouse B lineage cells with modulation by Smad.
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ABSTRACT: Bone morphogenetic proteins, including growth/differentiation factor-5 (GDF-5), are multifunctional cytokines. Recent studies of intracellular signal transduction mechanisms for the transforming growth factor-beta superfamily have focused on Smad proteins. However, scant attention has been given to the mechanism by which GDF-5 exerts its negative growth effect on immunological competent cells. In the present study, we demonstrated that GDF-5 induced cell cycle arrest in the G1 phase before the appearance of apoptosis in mouse B cell hybridoma HS-72 cells, while the ectopic expression of Smad6 and Smad7 in HS-72 cells suppressed the GDF-5-induced G1 cell cycle arrest by abolishing the expression of p21(CIP-1/WAF-1) and hypophosphorylation of retinoblastoma protein. Moreover, we found that Smad6 and Smad7 suppressed GDF-5-induced apoptosis in HS-72 cells. These findings indicated that Smad6 and Smad7 exhibit inhibitory effects toward GDF-5-mediated signaling in B lineage cells.Cellular Signalling 03/2003; 15(2):181-7. · 4.06 Impact Factor -
Article: [Tooth loss and osteoporosis].
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ABSTRACT: In spite of promoting the 8020 campaign in Japan, the number of residual teeth is 4.6 at the age of 80. The dental loss in adult is caused mainly by caries and/or periodontal disease. Although both osteoporosis and periodontal disease show symptoms to bone tissue, the correlation between osteoporosis and periodontal disease still remains not so clear. Further studies are necessary to detail the mechanism of periodontal bone resorption influenced by not only local factors but also systemic condition of bone metabolism.Clinical calcium 08/2002; 12(7):987-91.
Top co-authors
Top Journals
Institutions
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2007–2012
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Showa University
- Department of Biochemistry
Shinagawa-ku, Japan
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2002–2003
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Kagoshima University
- Department of Periodontology
Kagoshima-shi, Kagoshima-ken, Japan
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