Jun Ishibashi, Kikuji Yamashita, Tatsuo Ishikawa, Hiroyoshi Hosokawa, Kaori Sumida, Masaru Nagayama and Seiichiro Kitamura : The effects inhibiting the proliferation of cancer cells by far-infrared radiation (FIR) are controlled by the basal expression level of heat shock protein(HSP) 70A, Medical Oncology, 25, 2, 229-237, 2008.
(要約)
We developed a tissue culture incubator that can continuously irradiate cells with far-infrared radiation (FIR) of wavelengths between 4 and 20 microm with a peak of 7-12 microm, and found that FIR caused different inhibiting effects to five human cancer cell lines, namely A431 (vulva), HSC3 (tongue), Sa3 (gingiva), A549 (lung), and MCF7 (breast). Then, in order to make clear the control system for the effect of FIR, the gene expression concerned to the inhibition effect by FIR were analyzed. In consequence, basal expression level of HSP70A mRNA was higher in A431 and MCF7 cells than in the FIR-sensitive HSC3, Sa3, and A549 cells. Also, the over expression of HSP70 inhibited FIR-induced growth arrest in HSC3 cells, and an HSP70 siRNA inhibited the proliferation of A431 cells by irradiation with FIR. These results indicate that the effect of a body temperature range of FIR suppressing the proliferation of some cancer cells is controlled by the basal expression level of heat shock protein (HSP) 70A. This finding suggested that FIR should be very effective medical treatment for some cancer cells which have a low level of HSP70. Still more, if the level of HSP70 in any cancer of a patient was measured, the effect of medical treatment by FIR can be foreseen for the cancer.
Makoto Fukui, Masami Yoshioka, Kazuhito Satomura, Hiroaki Nakanishi and Masaru Nagayama : Specific-wavelength Visible Light Irradiation Inhibits the Growth of Porphyromonas gingivalis., Journal of Periodontal Research, 43, 2, 174-178, 2008.
(要約)
The effects of laser irradiation on Porphyromonas gingivalis have been reported, but the results are still controversial regarding the efficiency because of the differences of the light sources and irradiation conditions. The aim of this study was to determine the wavelength and irradiation conditions under which the most effective inhibitory effect on P. gingivalis growth was seen without any photosensitizers. Using an Okazaki large spectrograph, monochromatic light spectra ranging from 400 to 700 nm were evaluated to determine which spectra effectively inhibited bacterial growth. Moreover, using a monochromatic 405-nm irradiating device, the effects of various irradiating conditions on P. gingivalis growth were examined. Growth of bacteria irradiated at 400 nm and 410 nm was significantly suppressed compared with a nonirradiated control, whereas wavelengths of 430 nm and longer produced no significant inhibition. A constant energy density of 15 J/cm2 was found to be enough to show an inhibitory effect. Significant inhibition of bacterial growth was found after only 1 min at 50 mW/cm2 irradiation. These results indicate that P. gingivalis growth is specifically suppressed by 405-nm light irradiation, suggesting that visible blue light irradiation is a promising means for eradicating periodontopathogenic bacteria from periodontal lesions.
Masaaki Takechi, Seiko Tatehara, Kazuhito Satomura, Kenji Fujisawa and Masaru Nagayama : Effect of FGF-2 and melatonin on implant bone healing: a histomorphometric study ., Journal of Materials Science. Materials in Medicine, 19, 8, 2949-2952, 2008.
(要約)
Melatonin influences the release of growth hormone and cortisol in humans, and it was recently reported that it promoted bone formation. On the other hand, fibroblast growth factor-2 (FGF-2) was reported to facilitate the proliferation of osteoblasts. In the present study, we examined the effect of recombinant human FGF-2 and melatonin on the promotion of osteogenesis around titanium implants. Twenty-four 10-week-old female rats of the Wistar strain received titanium implants in both tibiae. In the experimental groups, 100 mg/kg body weight of melatonin was administered by intraperitoneal injection for 4 weeks after implantation and 10 microg of FGF-2 was locally injected around the implant sites 5 days after implantation. The control groups were administered saline only. In the control group, few newly formed bone could be seen around the implants. It was observed to be in direct contact with the implant surface, but otherwise unmineralized connective tissue was occasionally interposed. In the experimental group, newly formed bone was observed around the titanium implant. In addition, in contrast to the control group, abundant bone trabeculae were seen in the medullary canal region. Bone trabeculae were directly connected to existing cortical bone. These results strongly suggested that melatonin and FGF-2 have the potential to promote osseointegration.
(キーワード)
Animals / Bone Development / Female / Fibroblast Growth Factor 2 / Humans / Injections, Intraperitoneal / Melatonin / Prostheses and Implants / Rats / Rats, Wistar / Recombinant Proteins
Kazuhito Satomura, Reiko Tokuyama, Tetsuya Yuasa, Y Yamasaki, Seiko Tatehara, Naozumi Ishimaru, Yoshio Hayashi and Masaru Nagayama : Possible involvement of stem cell factor and endothelin-1 in the emergence of pigmented squamous cell carcinoma in oral mucosa., Journal of Oral Pathology & Medicine, 36, 10, 621-624, 2007.
(要約)
We present here the clinical, morphological and immunohistochemical features of a pigmented squamous cell carcinoma (SCC) in the oral mucosa of the hard palate of a 76-year-old Japanese man. He underwent a partial resection of the maxilla subsequent to radiotherapy. The tumor was typical, moderately well-differentiated SCC but had many melanocytes (melanocytosis) within it. Immunohistochemical analysis for stem cell factor (SCF) and endothelin-1, both of which are known to stimulate proliferation and differentiation of melanocytes, revealed prominent expression of both factors in the neoplastic squamous cells of the pigmented SCC, while the non-pigmented oral SCC showed little sign of either factor. These findings strongly suggest that SCF and endothelin-1 secreted by neoplasmic squamous cells are involved in the emergence of a rare variant of oral SCC.
Tissue response to apatite cement (AC) containing atelocollagen (AC (ate)) was evaluated using conventional AC (c-AC) as a control material. At one week, the only difference between AC (ate) and c-AC was found in the soft tissue response. With c-AC, a moderate inflammatory response was exhibited: small particles of c-AC were scattered in the cutaneous tissue and many foreign body giant cells were aggregated around the scattered c-AC, whereas AC (ate) showed only a slight inflammatory response with few foreign body giant cells. In terms of bone tissue response, difference between AC (ate) and c-AC was observed at four weeks. New bone formation was observed along the cement at the edge of the pre-existing cortical bone in both c-AC and AC (ate). However, in the case of AC (ate), more abundant and thicker new bone was formed along the cement in the bone marrow when compared with c-AC.
(キーワード)
Animals / Bone Cements / Bone Regeneration / Bone and Bones / Cattle / Collagen / Foreign-Body Reaction / Hydroxyapatites / Male / Rats / Rats, Wistar / Subcutaneous Tissue / X-Ray Diffraction
Kazuhito Satomura, Masayuki Kon, Reiko Tokuyama, Tomonari Mayumi, Masaaki Takechi, Tetsuya Yuasa, Seiko Tatehara and Masaru Nagayama : Osteopetrosis complicated by osteomyelitis of the mandible: a case report including characterization of the osteopetrotic bone, International Journal of Oral and Maxillofacial Surgery, 36, 1, 86-93, 2007.
(要約)
A case of a 53-year-old Japanese man with osteopetrosis complicated by osteomyelitis of the mandible is presented. The patient experienced frequent exacerbations and remissions of osteomyelitis of the mandible, despite undergoing several surgical debridements and sequesterectomies with appropriate antimicrobial therapy, for 3 years. Finally, the patient underwent mandibular segmental resection followed by reconstruction with a titanium reconstruction plate. Fifty-one months after surgery there is no evidence of recurrent osteomyelitis of the mandible, suggesting that a more radical surgical approach is preferable for patients with severe complications resulting from osteopetrosis. Also presented here are the histopathological and biochemical features of the osteopetrotic bone. The osteopetrotic cortical bone was morbidly sclerotic with compact and irregular laminations. Degradation of osteocytes in the osteopetrotic bone was due to hypoxia and lack of nutrition resulting from osteosclerosis. There were no significant differences between osteopetrotic and normal bone according to X-ray diffraction, Fourier transform infrared spectroscopy, collagen content or mineral content. Micro-Vickers hardness measurements showed that osteopetrotic bone was significantly harder than normal bone, and the standard deviation of hardness was greater in osteopetrotic bone. Such a loss of integrity in osteopetrotic bone is considered to be a primary reason for the greater risk of a variety of complications such as pathological fracture and refractory osteomyelitis.
Hiroyoshi Hosokawa, Kikuji Yamashita, Jun Ishibashi, Nanami Ishikawa, Hiroyuki Morimoto, Tomoyasu Ishikawa, Seiichiro Kitamura and Masaru Nagayama : A New Animal Raiser: Effect of Low Temperature Narrow Wavelength Far Infrared Radiation on Tumor Growth of A431 Cells, ITE Letters on Batteries, New Technologies & Medicine, 6, 6, 597-602, 2005.
Kikuji Yamashita, Hiroyoshi Hosokawa, Ishibashi Jun, Ishikawa Nanami, Hiroyuki Morimoto, Ishikawa Tomoyasu, Masaru Nagayama and Seiichiro Kitamura : Development of CO2 Iincubator with Limited Far-Infrared Radiation for Activation of Mitochondrial Metabolism, ITE Letters on Batteries, New Technologies & Medicine, 6, 5, 468-472, 2005.
dental implant / early louding / immediate loading / load
14.
Tetsuya Yuasa, Youji Miyamoto, Masayuki Kon, Kunio Ishikawa, Masaaki Takechi, Yukihiro Momota, Seiko Tatehara, Hideyuki Takano, Shiro Minamiguchi and Masaru Nagayama : Proliferation and Differentiation of Cultured MC3T3-E1 Osteoblasts on Surface-layer Modified Hydroxyapatite Ceramic with Acid and Heat Treatments, Dental Materials Journal, 24, 2, 207-212, 2005.
(要約)
Effects of functionally gradient calcium phosphate consisting of hydroxyapatite (HAP) and alpha-tricalcium phosphate (alpha-TCP) on proliferation and differentiation of osteoblasts were evaluated using MC3T3-E1 cells. There were no significant differences in the proliferation of MC3T3-E1 cells among HAP-alpha-TCP functionally gradient calcium phosphate, pure HAP, and cell culture plastic wells. mRNA expressions of type I collagen, alkaline phosphate, and osteocalcine were evaluated as indexes of initial; mid-stage, and late-stage osteoblastic differentiation. Basically, HAP-alpha-TCP functionally gradient calcium phosphate and pure HAP enhanced the expressions of the three markers when compared with that of cell culture plastic wells. For type I collagen and alkaline phosphate expressions, HAP-alpha-TCP functionally gradient calcium phosphate showed the same expression level as pure HAP. For osteocalcine expression, HAP-alpha-TCP functionally gradient calcium phosphate showed a higher level than pure HAP. We concluded, therefore, HAP-alpha-TCP functionally gradient calcium phosphate has good potential to be a bone filler material with high osteoconductivity.
Nobuyuki Kamata, Ryouichi Fujimoto, Mayumi Tomonari, Masayuki Taki, Masaru Nagayama and Shigeru Yasumoto : Immortalization of human dental papilla, dental pulp, periodontal ligament cells and gingival fibroblasts by telomerase reverse transcriptase, Journal of Oral Pathology & Medicine, 33, 7, 417-423, 2004.
(要約)
Human telomerase reverse transcriptase (hTERT) is catalytic subunit of human telomerase. We studied the immortalization of a series of human dental and periodontal cells by ectopic expression of hTERT and co-expression of hTERT with human papilloma virus 16 (HPV16) or simian virus 40 (SV40). Differentiation abilities of the established cell lines were studied in terms of the mineralized matrix formation and gene expression. We established immortalized gingival fibroblasts by hTERT, dental papilla and periodontal ligament cells by hTERT and HPV16, and pulp cells by hTERT and SV40. The papilla and pulp cells showed mineralization and dentin sialophosphoprotein (DSPP) expression when cultured in the presence of beta-glycerophosphate. The immortalized periodontal ligament cells did not show mineralization or DSPP expression, although expressions of alkaline phosphatase, osteopontin and osteocalcin were detected. These cell lines will be useful tools for studying the repair and regeneration of dental and periodontal tissues and various diseases including odontogenic tumors.
We report a case of multiple oral cancer with aplastic anemia.<BR>The patient was 25-year-old man who was referred to our department for treatment of a mass in the right side of the maxillary gingiva in July 2001. He was given a diagnosis of aplastic anemia at 7 years of age. The maximum amount of mouth opening was 15mm, and a mass with an ulcer was present in the right upper molar region. Computed tomographic examination showed a mass and bone defect in the right maxillary sinus. A biopsy was performed, and the histopathological diagnosis was squamous cell carcinoma. After radiation therapy (external irradiation with <SUP>60</SUP>Co-γ rays), we conducted operation. Red cell and platelet transfusions as well as granulocyte colony-stimulating factor (G-CSF) administration were performed before operation because of decreased numbers of blood cells, and the patient underwent a pertial maxillectomy.<BR>In October 2002, a tumorous lesion appeared in the left side of the mandibular gingiva, and a biopsy revealed squamous cell carcinoma. After the platelet transfusion, resection of the tumor was performed. There has been no evidence of recurrence or metastasis for more than 1 year after surgery.
(キーワード)
aplastic anemia / multiple oral cancer / squamous cell carcinoma
Satoshi Tsutsumi, Nobuyuki Kamata, J Tamara Vokes, Yutaka Maruoka, Koichi Nakakuki, Shoji Enomoto, Ken Omura, Teruo Amagasa, Masaru Nagayama, Fumiko Saito-Ohara, Johji Inazawa, Maki Moritani, Takashi Yamaoka, Hiroshi Inoue and Mitsuo Itakura : The novel gene encoding a putative transmembrane protein is mutated in gnathodiaphyseal dysplasia (GDD)., American Journal of Human Genetics, 74, 6, 1255-1261, 2004.
(要約)
Gnathodiaphyseal dysplasia (GDD) is a rare skeletal syndrome characterized by bone fragility, sclerosis of tubular bones, and cemento-osseous lesions of the jawbone. By linkage analysis of a large Japanese family with GDD, we previously mapped the GDD locus to chromosome 11p14.3-15.1. In the critical region determined by recombination mapping, we identified a novel gene (GDD1) that encodes a 913-amino-acid protein containing eight putative transmembrane-spanning domains. Two missense mutations (C356R and C356G) of GDD1 were identified in the two families with GDD (the original Japanese family and a new African American family), and both missense mutations occur at the cysteine residue at amino acid 356, which is evolutionarily conserved among human, mouse, zebrafish, fruit fly, and mosquito. Cellular localization to the endoplasmic reticulum suggests a role for GDD1 in the regulation of intracellular calcium homeostasis.
Masaaki Takechi, Youji Miyamoto, Yukihiro Momota, Tetsuya Yuasa, Seiko Tatehara, Masaru Nagayama and Kunio Ishikawa : Effects of various sterilization methods on the setting and mechanical properties of apatite cement, Journal of Biomedical Materials Research. Part B, Applied Biomaterials, 69B, 1, 58-63, 2004.
(要約)
Sterilization capability is a necessary requirement for any material that is to be used in a medical application. Therefore, it is necessary for apatite cement (AC) to be sterilized. Because there is little information on the sterilization methods of AC, the aims of this investigation were to evaluate the effects of various sterilization methods, including steam, dry heat, ethylene oxide (EtO) gas, and gamma irradiation sterilizations, on the setting and mechanical properties of AC. In the case of steam sterilization, because AC powder aggregated before setting-time measurements, the setting time could not be measured. When the powder was sterilized by dry heat or EtO gas, the setting time was prolonged significantly and the wet diametral tensile strength (DTS) value decreased significantly. Therefore, sterilizations with steam, dry heat, or EtO gas were suggested to be inappropriate methods for AC. Accordingly, the following experiments focused on gamma sterilization. The setting time of AC was retarded with an increase in gamma irradiation dose. The wet DTS value decreased with the increase in gamma irradiation dose. There was no compositional change due to the gamma irradiation. The following tests were carried out in order to examine the effect of the gamma irradiation on the setting reaction of AC in detail. Tetracalcium phosphate [TTCP: Ca(4)(PO(4))(2)O] and dicalcium phosphate anhydrous (DCPA: CaHPO(4)) were separately irradiated, and the cements were produced with the use of irradiated powder and nonirradiated powder. Although the wet DTS value of AC produced from irradiated TTCP and nonirradiated DCPA decreased with increasing gamma irradiation dose, there was no significant difference. In contrast, the wet DTS value of AC produced from irradiated DCPA and nonirradiated TTCP significantly decreased with the increase in gamma irradiation dose. In conclusion, although the detailed mechanism of the delayed setting time and decreased DTS value was not clarified by the present study, it was found that gamma irradiation affected DCPA more than TTCP.
Yukihiro Momota, Youji Miyamoto, Kunio Ishikawa, Masaaki Takechi, Tetsuya Yuasa, Seiko Tatehara and Masaru Nagayama : Effects of neutral sodium hydrogen phosphate on the setting property and hemostatic ability of hydroxyapatite putty as a local hemostatic agent for bone, Journal of Biomedical Materials Research. Part B, Applied Biomaterials, 69B, 1, 99-103, 2004.
(要約)
Hydroxyapatite (HAP) putty has been reported to have good hemostatic ability and excellent biocompatibility. Although the setting reaction of HAP putty and resulting transformation to HAP is the reason for this excellent biocompatibility, it also limits the handling period. In this study, the relationship between the setting reaction of HAP putty and its hemostatic ability was investigated, where neutral sodium hydrogen phosphate concentration and post-preparation time were used as indexes. A higher concentration of neutral sodium hydrogen phosphate was found to result in decreased hemostatic ability. The hemostatic ability of HAP putty decreased with time after its preparation; thus it was important to use HAP putty within 10 min after its preparation. The adhesive strength of HAP putty to bone increased with time. Therefore reliable hemostasis can be expected with HAP putty. Although the limited handling time is a drawback, HAP putty is thought to have a good potential as a hemostatic agent-it is highly reliable, and has a high hemostatic ability with excellent biocompatibility.
Tetsuya Yuasa, Youji Miyamoto, Kunio Ishikiawa, Masaaki Takechi, Yukihiro Momota, Seiko Tatehara and Masaru Nagayama : Effects of apatite cements on proliferation and differentiation of human osteoblasts in vitro, Biomaterials, 25, 7-8, 1159-1166, 2004.
(要約)
Although apatite cement (AC) and sintered hydroxyapatite (s-HAP) are known to show good osteoconductivity, it is not clear whether or not the degree of their osteoconductivity is the same. In addition, it has not been clarified whether or not it is dependent on the type of AC; conventional AC (c-AC), fast-setting AC (fs-AC) or anti-washout AC (aw-AC). The aim of this study was to investigate the effects of ACs on cultured human osteoblasts, as they may provide a useful index of osteoconductivity. Human osteoblasts were cultured on the surfaces of ACs and s-HAP, and were evaluated with respect to cell attachment, proliferation, and differentiation. We found that ACs and s-HAP showed similar cell attachment. No significant difference between ACs and s-HAP was found with respect to the proliferation of osteoblasts. In contrast, we found that the differentiation of osteoblasts was enhanced on the surface of ACs compared with that of s-HAP. However, there was no difference among the types of AC. We therefore concluded that AC may show better osteoconductivity than s-HAP, and that osteoconductivity of AC may be similar, regardless of the type of AC.
Youji Miyamoto, Kenji Fujisawa, Masaaki Takechi, Yukihiro Momota, Tetsuya Yuasa, Seiko Tatehara, Masaru Nagayama and Eiji Yamauchi : Effect of the additional installation of implants in the posterior region on the prognosis of treatment in the edentulous mandibular jaw, Clinical Oral Implants Research, 14, 6, 727-733, 2003.
(要約)
The aim of this study was to elucidate the effect of the additional installation of implants in the posterior region on the prognosis of treatment in the edentulous mandibular jaw. Fifteen patients who had received implants (Brånemark system, Nobel Biocare, Gotebörg, Sweden) in the edentulous mandible and completed a 1-year follow-up after the fitting of implant-anchored fixed prostheses were selected. In seven patients (Group A), four or five implants were installed between the mental foramina, and in eight patients (Group P), one or two implants, one on each side, were installed in the posterior regions in addition to the implants between the foramina. All implants of both groups achieved osseointegration. In Group A, there was no implant loss after loading. Six implants were lost in five patients of Group P within 1 year after loading. All of them were located in the posterior region. To elucidate whether or not the failure rate of the implants in the posterior region of Group P after loading was especially high, the failures were also compared with 89 implants, which were installed in the posterior region of the mandibles to support implant-anchored fixed partial prosthesis, during the same period (Group C). The cumulative survival rate of the implants of Group P was 60%, while that of the implants of Group C was 100% (P<0.001). When the survival rates of posterior implants with the same length of the two groups were compared, there were significant differences for the 7- and 10-mm-length implants only. These data demonstrate that the posterior implants in Group P are at greater risk. Deformation of the mandible due to jaw movement was thought to be the most likely cause of the implant loss. Therefore, when such modified treatment is chosen, it should be performed with meticulous attention.
Although synovial chondromatosis occurs frequently near the ends of long bones, such as the knee, elbow, and hip joints, it rarely affects the temporomandibular joint.<BR>A 52-year-old woman visited our hospital because of swelling in the left side of the temporomandibular joint and trismus. On magnetic resonance imaging, the lesion was found to be chondroid tissue between the left mandibular fossa and the condylar head. Magnetic resonance imaging revealed a high signal mass measuring 35×40mm around the left condylar head. The clinical diagnosis was synovial chondromatosis. Synovectomy and removal of the mass were performed with the patient under general anesthesia. Histopathologically, the mass was formed by typical chondrocytes and was diagnosed to be synovial chondromatosis. The patient has been followed up for 1 year 4 months. There has been no reccurence of the mass or temporomandibular joint disorder.
Masayuki Taki, Nobuyuki Kamata, Kazuhiro Yokoyama, Ryoichi Fujimoto, Satoshi Tsutsumi and Masaru Nagayama : Down-regulation of Wnt-4 and up-regulation of Wnt-5a expression by epithelial-mesenchymal transition in human squamous carcinoma cells, Cancer Science, 94, 7, 593-597, 2003.
(要約)
Gene expression of Wnt-1, 2, 3, 4, 5a, 6 and 7a was analyzed by RT-PCR in eleven squamous cell carcinoma (SCC) cell lines and compared with that in two normal oral keratinocyte strains. There appeared to be an inverse relationship between Wnt-4 and Wnt-5a expressions, i.e., Wnt-4 was not expressed in HOC719-NE, HOC313 or TSU cells, while Wnt-5a was strongly expressed only in these cells. These cell lines showed decreased expression of E-cadherin and elevated expression of vimentin accompanied with strong expressions of Snail and deltaEF1, which have been reported to be transrepressors of E-cadherin and to trigger epithelial-mesenchymal transition (EMT), suggesting associations of Wnt-4 with epithelial phenotype and Wnt-5a with mesenchymal phenotype of SCC cells. To study whether the expressions of these Wnt genes are regulated by EMT, we transfected a Snail-expression vector into A431 and OM-1 cells, which express Wnt-4 but not Wnt-5a. The stably Snail-overexpressing clones showed spindle morphology, increased expression of vimentin and decreased expression of E-cadherin accompanied with augmented expression of deltaEF1. In these clones, down-regulation of Wnt-4 and up-regulation of Wnt-5a were clearly observed. These results indicated that Wnt-4 and Wnt-5a are oppositely affected by EMT, and down-regulation of Wnt-4 and up-regulation of Wnt-5a are possible markers of the malignant phenotype of human SCC.
Kazuhiro Yokoyama, Nobuyuki Kamata, Ryoichi Fujimoto, Seiji Tsutsumi, Mayumi Tomonari, Masayuki Taki, Hiroyoshi Hosokawa and Masaru Nagayama : Increased invasion and matrix metalloproteinase-2 expression by Snail-induced mesenchymal transition in squamous cell carcinomas., International Journal of Oncology, 22, 4, 891-898, 2003.
(要約)
Loss of E-cadherin expression is a major characteristic of highly invasive and metastatic cancers. Epithelial-mesenchymal transition (EMT) has been advocated to be a causative mechanism for the suppression of E-cadherin and tumor progression. Snail is a zinc finger transcription factor that triggers the EMT and is one of the recently identified E-cadherin repressors. The reverse correlation of Snail and E-cadherin expressions has been reported in many types of human cancers including squamous cell carcinoma (SCC). In this study, we showed that three E-cadherin negative SCC cell lines had a fibroblastic morphology, strong expressions of vimentin, a mesenchymal marker gene, and Snail. Compared to other E-cadherin positive SCC cells, these cells showed higher invasive ability and expression of MMP-2, a matrix degrading enzyme which has been demonstrated to be highly expressed in invasive cancer cells. Over-expression of Snail in A431 cells resulted in the loss of E-cadherin expression, the change of their morphology to fibroblastic, and the up-regulation of vimentin gene expression, indicating that an EMT was induced by Snail. Furthermore, these cells became more invasive and showed higher levels of MMP-2 activity and its gene expression. Luciferase analysis demonstrated that the MMP-2 promoter activity was induced by Snail transfection and the promoter region from -262 to -411 relative to the transcriptional start site was necessary for this induction. These results indicate that Snail is a new inducer of MMP-2 expression and suggest that the EMT contributes to the increased invasion not only through the inhibition of cell-cell adhesion but also the up-regulation of MMP-2 expression in SCC cells.
SATOSHI TSUTSUMI, NOBUYUKI KAMATA, YUTAKA MARUOKA, MIKI ANDO, OSAMU TEZUKA, SHOJI ENOMOTO, KEN OMURA, Masaru Nagayama, Eiji Kudo, MAKI MORITANI, TAKASHI YAMAOKA and Mitsuo Itakura : Autosomal Dominant Gnathodiaphyseal Dysplasia Maps to Chromosome 11p14.3-15.1, Journal of Bone and Mineral Research, 18, 3, 413-418, 2003.
(要約)
Gnathodiaphyseal dysplasia (GDD) is a syndrome characterized by bone fragility, sclerosis of tubular bones, and cemento-osseous lesions of jawbones. Although some cases of this syndrome exist in families with autosomal dominant inheritance, the underlying gene has never been identified. We analyzed a large four-generation family with GDD by linkage analysis using genomic DNA from nine affected and six nonaffected family members. A genome-wide search using a set of highly polymorphic microsatellite markers showed evidence for linkage to chromosome 11p14.3-15.1. Two-point linkage analysis of microsatellite markers spanning this locus resulted in a maximum logarithm of odds (LOD) score of 2.70 with a recombination fraction (theta) of 0 at D11S1755, D11S1759, and D11S915, and a maximum LOD score of 3.01 at D11S4114 was obtained in multipoint linkage analysis. Haplotype analysis detected no recombination between GDD and six closely linked markers (D11S928, D11S1755, D11S4114, D11S1759, D11S915, and D11S929) and established the candidate interval of 8.7 cM on chromosome 11p for GDD. Although GDD has been considered to be a variation of osteogenesis imperfecta (MIM 166260), our results indicate that this syndrome is a new and distinct disease entity from other systemic bone diseases. Furthermore, these genetic markers are useful for presymptomatic diagnosis of GDD in some families and for identification of the GDD gene.
Masaaki Takechi, Youji Miyamoto, Yukihiro Momota, Tetsuya Yuasa, Seiko Tatehara, Masaru Nagayama, Kunio Ishikawa and Kasuomi Suzuki : The in vitro antibiotic release from anti-washout apatite cement using chitosan, Journal of Materials Science. Materials in Medicine, 13, 10, 973-978, 2002.
(要約)
The in vitro antibiotic release from anti-washout apatite cement using chitosan (aw-AC(chi)) was investigated in a preliminary evaluation. Flomoxef sodium was employed as the antibiotic and was incorporated into the powder phase aw-AC(chi) at up to 10%. The setting times were measured for aw-AC(chi) containing various amounts of flomoxef sodium. X-ray diffraction (XRD) analysis was also conducted for the identification of products. To evaluate the drug release profile, set aw-AC was immersed in saline and the released flomoxef sodium was determined at regular intervals. The setting time was prolonged slightly with the addition of flomoxef sodium. The difference at 10% flomoxef sodium (0% vs. 10%) was not significant (p>0.05), and can be negligible in clinic. The XRD analysis revealed that formation of hydroxyapatite (HAP) from aw-AC(chi) was reduced, even after 24 h, when the aw-AC(chi) contained flomoxef sodium at 8% or more. The flomoxef sodium release from aw-AC(chi) showed the typical profile observed in skeleton type drug delivery system (DDS). Changing the concentration of chitosan can control the rate of drug release from aw-AC. Therefore, we conclude that aw-AC(chi) is a good candidate for potential use as a DDS carrier that may be useful in surgical operations.
Masami Ninomiya, Nobuyuki Kamata, Ryoichi Fujimoto, Tomoko Ishimoto, (名) Suryono, Jun-ichi Kido, Masaru Nagayama and Toshihiko Nagata : Application of Enamel Matrix Derivative in Autotransplantation of an Impacted Maxillary Premolar, Journal of Periodontology, 73, 3, 346-351, 2002.
(要約)
The success of tooth transplantation or replantation depends on the viability of periodontal ligament in the planted tooth. Mechanical injury to periodontal tissues frequently results in dental root resorption and dental ankylosis, which leads to the failure of transplantation or replantation. Enamel matrix derivative (EMD) has been recently used to induce periodontal regeneration. In this report, we show a clinical case of EMD application in the transplantation of an inversely impacted and immature tooth. An impacted second premolar was found in the right maxilla of a 16 year-old girl. The tooth was inversely impacted and the dental root was incomplete. When transplantation was carried out, EMD was applied to the periodontal tissues of the extracted premolar. The tooth was fixed at the correct position and the clinical condition was followed for evaluation for 6 months. Radiographs after 3 months exhibited new bone formation surrounding the transplanted tooth. After 6 months, considerable growth of dental root was evident, periodontal ligament-like radiolucency appeared, the vital reaction of the planted tooth was detected, and there were no signs of root resorption or ankylosis. Short-term results from this case indicate that EMD application was effective in the transplantation of an inversely impacted and immature tooth and that EMD might contribute to the growth of dental root and to the prevention of ankylosis.
Keiko Kudoh, Kazuhito Satomura, Sachiko Nishisho, Eiichiro Kitaoka, Kouji Yamanouchi, Satoru Tobiume and Masaru Nagayama : Potential role of leptin in endochondral ossification, The Journal of Histochemistry and Cytochemistry, 50, 2, 159-170, 2002.
(要約)
Leptin, a 16-kD circulating hormone secreted mainly by white adipose tissue, is a product of the obese (ob) gene. Leptin acts on human marrow stromal cells to enhance differentiation into osteoblasts and inhibit differentiation into adipocytes. Leptin also inhibits bone formation through a hypothalamic relay. To obtain a better understanding of the potential role of leptin in bone formation, the localization of leptin in endochondral ossification was examined immunohistochemically. High expression of leptin was identified in hypertrophic chondrocytes in the vicinity of capillary blood vessels invading hypertrophic cartilage and in a number of osteoblasts of the primary spongiosa beneath the growth plate. The hypertrophic chondrocytes far from the blood vessels were negative for leptin. Moreover, we detected the production and secretion of leptin by a mouse osteoblast cell line (MC3T3-E1) and a mouse chondrocyte cell line (MCC-5) by RT-PCR, immunocytochemistry, and Western blotting. Leptin enhanced the proliferation, migration, tube formation, and matrix metalloproteinase-2 (MMP-2) activity of human endothelial cells (HUVECs) in vitro. These findings suggest the possibility that leptin exerts its influence on endochondral ossification by regulating angiogenesis.
Kunio Ishikawa, Youji Miyamoto, Tetsuya Yuasa, Atsuo Ito, Masaru Nagayama and Kazuomi Suzuki : Fabrication of Zn containing apatite cement and its initial evaluation using human osteoblastic cells, Biomaterials, 23, 2, 423-428, 2002.
(要約)
Recently, the effects of Zn2+ on osteogenesis stimulation have become major topics in the research fields of bone formation and organism essential elements. Based on the fundamental finding of Zn2+ with respect to osteogenesis stimulation, Ito et al. have prepared Zn doped beta-tricalcium phosphate (ZnTCP) and have reported that ZnTCP enhances the proliferation of MC3T3-E1 cells. In this investigation, we studied the effects of ZnTCP added to apatite cement (AC) with respect to its setting reaction and proliferation of human osteoblastic cells as an initial evaluation for the feasibility of AC containing ZnTCP. Compositional analysis using powder X-ray diffractometer revealed that ZnTCP shows no reactivity with the setting reaction of AC. As a result, the mechanical strength of set AC decreased increasing amounts of added ZnTCP as if ZnTCP acts as a pore in AC. The setting time of AC was not affected by addition of ZnTCP up to 10%. When AC containing ZnTCP was immersed in alpha-MEM containing 10% bovine serum, Zn2+ was released from AC. Larger amounts of Zn2+ were released from AC containing larger amounts of ZnTCP. When human osteoblastic cells were incubated on the surface of AC discs, proliferation of human osteoblastic cells was significantly increased on the surface of AC that contained 5% ZnTCP when compared with that containing no ZnTCP. In contrast, proliferation of human osteoblastic cells decreased on the surface of AC that contained 10% ZnTCP when compared with that free from ZnTCP; indicating cytotoxicity. We concluded therefore, that addition of ZnTCP to AC is useful to enhance the osteoconductivity of AC when release of Zn2+ can be carefully regulated.
Hidemi Sasaki, Takashi Yamaoka, Hideyo Ohuchi, Akihiro Yasue, Tsutomu Nohno, Hirotaka Kawano, Shigeaki Kato, Mitsuo Itakura, Masaru Nagayama and Sumihare Noji : Identification of cis-elements regulating expression of Fgf10 during limb development., The International Journal of Developmental Biology, 46, 7, 963-967, 2002.
(要約)
Fibroblast growth factor 10 (FGF10) is known to be expressed in limb mesenchymal cells and to function as a mesenchymal signaling factor involved in epithelial-mesenchymal interactions during limb development. To elucidate regulation of Fgf10 expression, we isolated the promoter region of Fgf10 containing its 2.0 kb upstream 5'-fragment from the initiation codon and its 0.9 kb downstream fragment. Transcriptional activity of the fragment was examined with transgenic mice, using a lacZ-reporter system. Although no significant expression of the reporter gene was observed for the 0.2 kb 5'-fragment, expression was detected in the apical ectodermal ridge of the limb bud and developing cartilage of the limb for the 2.0 kb and 0.7 kb 5'-fragments, respectively. From comparison of the mouse sequences of the 2.0 kb fragment with corresponding sequences of human and chicken Fgf10, we identified 17 conserved putative enhancer motifs for AER expression and other unidentified expressions. For limb cartilage expression, we found putative enhancer sequences conserved among the three species in the 0.7 kb 5'-fragment. In the fragment, three DNA binding motifs were identified in the mouse and human sequence, although they are not conserved in the corresponding chicken sequence.
Yukihiro Momota, Youji Miyamoto, Kunio Ishikawa, Masaaki Takechi, Tetsuya Yuasa, Seiko Tatehara, Masaru Nagayama and Kazuomi Suzuki : Evaluation of Feasibility of Hydroxyapatite Putty as a Local Hemostatic Agent for Bone., Journal of Biomedical Materials Research, 63, 5, 542-547, 2002.
(要約)
Although bone wax is known to cause an inflammatory reaction in soft tissue and a delay of bone healing, it is usually the first choice to arrest bleeding from bone. Hydroxyapatite (HAP) putty is proposed here. This study evaluated the feasibility of HAP putty with respect to whether or not it has potential value as a hemostatic agent for bone. First, the adhesive strength of HAP putty to bone was evaluated. The adhesive strength of HAP putty to wet bone was much higher when compared with that of bone wax, even though the adhesive strengths of HAP putty and bone wax to dry bone were equivalent. Next, to evaluate the hemostatic ability of HAP putty, bony defects were made in rabbits. HAP putty could arrest bleeding from bone within 3 min. However, when the hemostasis was performed with bone wax, bleeding was arrested within 8 min. Thus, HAP putty showed better hemostatic ability than bone wax. Finally, the tissue response to HAP putty in rabbit subcutaneous tissue was evaluated. Histological observation revealed a slight inflammatory response around HAP putty, whereas bone wax was surrounded by moderate inflammatory tissue. In conclusion, HAP putty has good potential value to be a hemostatic agent for bone because it has strong adhesion, good hemostatic ability, and biocompatibility.
Aspergillosis is caused by infection with <I>Aspergilli</I>. It is often difficult to make an exact diagnosis before identification of <I>Aspergilli</I> by microbial examination because aspergillosis is difficult to differentiate from other diseases. We present a case of aspergillosis of the maxillary sinus that could be diagnosed on serological examination for <I>Aspergilli</I> or fungi specific sugar.<BR>A 51-year-old woman visited to our hospital because of swelling in the gingiva of the maxilla. Radical operation of the maxillary sinus was performed for a clinical diagnosis of aspergillosis of the maxillary sinus. Histopathological examination revealed <I>Aspergilli</I> in the extirpated tissue of the maxillary sinus. Serological examinations showed elevated serum levels of galactomannan and β-D-glucan. Galactomannan is a specific marker for <I>Aspergilli</I>, and β-D-glucan is specific for fungi. Both makers fell to normal levels after operation, Suggesting that serological examinations for galactomannan and β-D-glucan are useful in the diagnosis of aspergillosis of the maxillary sinus.
Masaaki Takechi, Kunio Ishikawa, Youji Miyamoto, Masaru Nagayama and Kazuomi Suzuki : Tissue responses to anti-washout apatite cement using chitosan when implanted in the rat tibia, Journal of Materials Science. Materials in Medicine, 12, 7, 597-602, 2001.
(要約)
The tissue response to anti-washout apatite cement using chitosan (aw-AC(chi)) was evaluated by implanting aw-AC(chi) into bone defects of rat tibiae using conventional apatite cement (c-AC) as a control material. During the experimental period up to 16 weeks, the only difference between aw-AC and c-AC was found at two weeks in the tissue response of soft tissue. At two weeks, c-AC showed a moderate inflammatory response; small particles of c-AC were scattered in the cutaneous tissue and many foreign body giant cells were collected around the scattered c-AC, whereas aw-AC showed only a slight inflammatory response and few foreign body giant cells. We found no difference between aw-AC(chi) and c-AC with respect to bone tissue response. Both AC were almost completely surrounded by mature bone at eight weeks. No promotion or reduction of osteoconductivity was observed by chitosan even though it is considered to promote bone formation. We concluded, therefore, that enhancement of bone formation cannot be expected by employing chitosan to obtain anti-washout properties, at least in the concentration used in this study, even though aw-AC(chi) is much more useful than c-AC.
Kouji Yamanouchi, Kazuhito Satomura, Yuji Gotoh, Eiichiro Kitaoka, Satoru Tobiume, Keiko Kudoh and Masaru Nagayama : Bone formation by transplanted human osteoblasts cultured within collagen sponge with dexamethasone in vitro, Journal of Bone and Mineral Research, 16, 5, 857-867, 2001.
(要約)
To apply osteoblasts to bone reconstruction, we proved that transplanted osteoblasts possessed the differentiated osteoblastic function and formed bonelike tissue in vivo after transplantation. First, we confirmed that dexamethasone (Dex) promoted the expression of osteoblastic phenotype in human osteoblast culture using reverse-transcription-polymerase chain reaction (RT-PCR). These osteoblasts were cultured for 10 days within collagen sponge, which consists of denatured type I collagen, in the presence or absence of 10(-7) M Dex. The osteoblasts along with collagen sponge were transplanted into the trapezius muscles of 8-week-old severe combined immunodeficiency (SCID) mice, and the transplants were harvested at 2, 4, 6, and 8 weeks. At 2 weeks, Dex-treated osteoblasts formed bonelike tissue, the quantity of which increased in a time-dependent manner to 8 weeks. This bonelike tissue was composed of mineralized collagen matrix newly synthesized by the transplanted osteoblasts. This mineralized matrix was separated from the osteoblasts by nonmineralized matrixlike osteoid. Furthermore, many osteocytic cells were observed in this mineralized matrix. A high expression of alkaline phosphatase (ALPase) and osteocalcin was detected in the transplanted cells surrounding the bonelike tissue. In situ hybridization for human-specific alu sequence indicated that newly formed bone was of donor origin. The transplants of nontreated cells failed to form bonelike tissue. The transplants of collagen sponge alone formed no bonelike tissue. These studies indicate that Dex-treated human osteoblasts possess the differentiated osteoblastic function and are able to form bone tissue in vivo. These new findings are of use in facilitating the application of osteoblasts to bone reconstruction.
(キーワード)
Alkaline Phosphatase / Animals / Bone and Bones / Cell Transplantation / Cells, Cultured / Child / Collagen / Dexamethasone / Gene Expression / Humans / In Situ Hybridization / Male / Mice / Mice, SCID / Osteoblasts / Osteocalcin
Youji Miyamoto, Taketomo Toh, Kunio Ishikawa, Tetsuya Yuasa, Masaru Nagayama and Kazuomi Suzuki : Effect of added NaHCO3 on the basic properties of apatite cement, Journal of Biomedical Materials Research, 54, 3, 311-319, 2001.
(要約)
Alternation of a composition of set apatite cement (AC) from carbonate-free apatite (CO3-free AP) to carbonate apatite (CO3-AP) may accelerate replacement of the set AC with bone because CO3-AP can be dissolved much faster than CO3-free AP in the weak acidic solution produced by osteoclasts. In this investigation, NaHCO3 was added to the AC component and the effects of added NaHCO3 on cement-setting behavior and on set mass were studied as an initial step for the fabrication of AC, which can be replaced with bone faster than current AC. When NaHCO3 was added to AC, the resultant set mass contained CO3. Although not all CO3 was incorporated in the set AC, the amount of CO3 incorporated into the set AC increased with the amount of added NaHCO3. Powder X-ray diffraction analysis and Fourier transform infrared spectrometer measurements revealed the formation of B-type CO3-AP. The setting time measured in an incubator at 37 degrees C and 100% relative humidity slowed from 30 to 45 min, indicating that NaHCO3 has an inhibitory effect on AP formation. The diametral tensile strength of the set AC decreased significantly with the addition of NaHCO3. Scanning electron microscopic observation revealed that fine crystals were formed in the set AC when NaHCO3 was added to AC. As a result, the crystallinity indices of the set AC measured using X-ray diffraction and Fourier transform infrared spectroscopy decreased with an increase in the amount of added NaHCO3. The dissolution rate of set AC in weak acid, pH 5.5, increased with the amount of added NaHCO3. We concluded that the formation of B-type CO3-AP and the resulting faster dissolution of set AC in weak acidic solution is preferable for the faster replacement of set AC with bone even though the decreased diametral tensile strength value is a shortcoming.
Tetsuya Yuasa, Youji Miyamoto, Kunio Ishikiawa, Masaaki Takechi, Masaru Nagayama and Kazuomi Suzuki : In vitro resorption of three apatite cements with osteoclasts, Journal of Biomedical Materials Research, 54, 3, 344-350, 2001.
(要約)
To evaluate the replacement of apatite cement (AC) with bone, osteoclasts were incubated for 48 h on the surface of three AC types: conventional AC (c-AC), fast-setting AC (fs-AC), and anti-washout AC (aw-AC), using sintered apatite (AP) and cortical bone as control materials. We found osteoclasts attached to the surface of AC and osteoclastic resorption pits after 48 h of incubation for all experimental AC types. In contrast, no resorption pit was observed on the surface of sintered AP although osteoclasts were attached to the surface of sintered AP. There was no significant difference among the types of AC with respect to the resorption area, but the resorption areas were only approximately 1% of that on the surface of cortical bone. We concluded, therefore, that ACs could be replaced with bone regardless of the type but that it takes extensive time for the ACs to be completely replaced with bone.
Ryoichi Fujimoto, Nobuyuki Kamata, Kazuhiro Yokoyama, Naohiro Ueda, Kazuhito Satomura, Eiji Hayashi and Masaru Nagayama : Expression of telomerase components in oral keratinocytes and squamous cell carcinoma, Oral Oncology, 37, 2, 132-140, 2001.
(要約)
Telomerase activity was measured using a telomeric repeat amplification protocol (TRAP), and expressions of the telomerase components, telomerase associated protein 1 (hTEP1), human telomerase RNA component (hTR), and human telomerase reverse transcriptase (hTERT) were measured by reverse transcriptase-polymerase chain reaction (RT-PCR) in cultured normal oral keratinocytes and oral squamous cell carcinoma (SCC) cells. Telomerase localization was analyzed by in situ hybridization (ISH) in normal, precancerous and cancerous oral tissues. There was a strong correlation of telomerase activity with the expression levels of hTERT but not with hTEP1 or hTR mRNA in the cultured cells. Not only hTEP1 and hTR but also hTERT expression were detected in the basal cells of normal oral mucosa, and the cells expressing these mRNAs were also seen in the upper layer of leukoplakia of gingiva, and a heterogeneous pattern of expression was observed in the oral SCC tissues. These results indicate that there are at least two steps in the increase of telomerase activity during carcinogenesis in oral squamous cells; a change in distribution of cells expressing these telomerase components and the over-expression of hTERT gene in individual cells.
Kazuhiro Yokoyama, Nobuyuki Kamata, Eiji Hayashi, Tomoaki Hoteiya, Naohiro Ueda, Ryouichi Fujimoto and Masaru Nagayama : Reverse correlation of E-cadherin and snail expression in oral squamous cell carcinoma cells in vitro, Oral Oncology, 37, 1, 65-71, 2001.
(要約)
The loss of E-cadherin expression has been shown to correlate to the invasion and metastasis of many types of carcinomas. We established E-cadherin positive (HOC719-PE) and negative (HOC719-NE) clones from an oral squamous cell carcinoma (SCC). HOC719-PE cells showed epithelial morphology with E-cadherin expression in the cell membrane, whereas HOC719-NE cells demonstrated fibroblastic morphology without E-cadherin expression. In invasion assay and three dimensional culture, HOC719-NE showed much higher invasive ability than HOC719-PE cells. These cells expressed similar levels of mRNAs for alpha- and beta-catenin. However, HOC719-NE cells, but not HOC719-PE cells, showed strong expression of snail, a transcription factor implicated in the differentiation of epithelial cells into mesenchymal phenotype. This reverse expression of snail and E-cadherin was further observed in other SCC cells including HOC313, and TSU cells that we previously reported to show no expression of E-cadherin protein. These results indicated that the expression of snail has a key role for the acquisition of more invasive and metastatic phenotypes of SCC and the clones we reported here will be useful tools for understanding the mechanism of the transition from epithelial to mesenchymal SCC cells.
Eiichiro Kitaoka, Kazuhito Satomura, Eiji Hayashi, Keiko Kudoh, Satoru Tobiume and Masaru Nagayama : Establishment and charcterization of chondrocyte cell lines from the costal cartilage of SV40 large T antigen transgenic mice, Journal of Cellular Biochemistry, 81, 4, 571-582, 2001.
(要約)
Complete understanding of the physiology and pathology of the cartilage is essential to establish treatments for a variety of cartilage disorders and defects such as rheumatoid arthritis, congenital malformations, and tumors of cartilage. Although synthetic materials have been used in many cases, they possess inherent problems including wear of the materials and low mechanical strength. Autograft has been considered very effective to overcome these problems. However, the limitation of the transplant volume is a major problem in autograft to be overcome. The costal cartilage is the most serious candidate for donor site transplantation, since it is the largest permanent hyaline cartilage in the body. To investigate the possibility using the costal cartilage as a transplant source, we have established and characterized three mouse chondrocyte cell lines (MCC-2, MCC-5, and MCC-35) derived from the costal cartilage of 8-week-old male SV40 large T-antigen transgenic mice. At confluence, all the cell lines formed nodules that could be positively stained with alcian blue (pH 2.5). The size of nodules gradually increased during culturing time. After 2 and 6 weeks of culture, RT-PCR analysis demonstrated that all three cell lines expressed mRNA from the cartilage-specific genes for type II collagen, type XI collagen, aggrecan, and link protein. Furthermore, type X collagen expression was detected in MCC-5 and MCC-35 but not in MCC-2. Any phenotypic changes were not observed over 31 cell divisions. Immunocytochemistry showed further that MCC-2, MCC-5, and MCC-35 produced cartilage-specific proteins type II collagen and type XI collagen, while in addition MCC-5 and MCC-35 produced type X collagen. Treatment with 1alpha, 25-dihydroxyvitamin D(3) inhibited cell proliferation and differentiation of the three cell lines in a dose-dependent manner. These phenotypic characteristics have been found consistent with chondrocyte cell lines established from cartilage tissues other than costal cartilage. In conclusion, costal cartilage shows phenotypic similarities to other cartilages, i.e., articular cartilage and embryonic limbs, suggesting that costal cartilage may be very useful as the donor transplantation site for the treatment of cartilage disorders. Furthermore, the cell lines established in this study are also beneficial in basic research of cartilage physiology and pathology.
We describe a case of first and second branchial arch syndrome in a patient whose profile and occlusion improved in response to orthognatic surgery.<BR>A 2-year-9-month-old boy was referred to our clinic for the treatment of open bite. Because symptoms were mild the patient was placed under observation. However, open bite and bird face became severer as he grew older. Cephalometric analysis indicated mandibular micrognathia. Before operation, we made and analyzed computer tomography-based three-dimensional models. The models were very useful for operation planning. After preoperative orthodontic treatment, sagittal splitting ramus osteotomy and horizontal sliding advancement genioplasty were performed in two stages.
Naohiro Ueda, Nobuyuki Kamata, Eiji Hayashi, Kazuhiro Yokoyama, Toshiaki Hoteiya and Masaru Nagayama : Effects of an anti-angiogenic agent, TNP-470, on the growth of oral squamous cell carcinomas, Oral Oncology, 35, 6, 554-560, 1999.
(要約)
Anti-tumor effects of an anti-angiogenic agent, TNP-470, on the growth of oral squamous cell carcinomas (SCCs) were evaluated in vivo and in vitro. The growth of an oral SCC cell line, HSC-2, inoculated subcutaneously in severe combined immuno-deficiency (SCID) mice was inhibited in a dose-dependent manner by the treatment with this agent. A reduction of microvessels surrounding tumor tissues treated with TNP-470 was observed by immunohistochemistry. Significant side-effects were not observed except for weight loss during the period of treatment with high dose (50 mg/kg) of TNP-470. The direct effects of TNP-470 on oral SCC cell lines were also evaluated in culture. The growth of all eight SCC cell lines tested was inhibited by TNP-470, but the sensitivity of the oral SCC cell lines to TNP-470 was about 1700 times less than that of endothelial cells. These results suggest that TNP-470 inhibits the growth of oral SCC by anti-angiogenic activities and that it may be effective as a new therapy of oral cancer.
Kazuhito Satomura, Hiroaki Nakanishi, Kenji Fujisawa, Eiji Hayashi and Masaru Nagayama : Initiation of ectopic epithelial calicification in a calcifying odontogenic cyst, Journal of Oral Pathology & Medicine, 28, 7, 330-335, 1999.
(要約)
Ultrastructural observation was performed on a calcifying odontogenic cyst (COC) associated with an odontoma and arising in the right mandibular region of an 8-year-old Japanese boy. Four types of cells were identified in the epithelial layer of the COC. The basal cells were low columnar in shape and contained some intracellular organelles. They were attached to the neighboring cells with a few desmosomes and resembled inner enamel epithelium of the normal enamel organ. The stellate reticulum-like cells, polygonal in shape, possessed desmosomes and many cytoplasmic projections. Some intracellular organelles and a few bundles of tonofilaments were observed in the cytoplasm. The light oval cells that were pale staining with toluidine blue contained dilated membranous organelles and many relatively evenly distributed tonofilaments. These cells were usually scattered in the vicinity of the focal accumulations of ghost cells, and the cell membrane was discontinuous in parts. The ghost cells contained many bundles of tonofilaments that were 60-240 nm in diameter and arranged in various directions. No intact intracellular organelles were noted in the cytoplasm. They were attached to the neighboring ghost cells with some desmosomes and their cell membrane was discontinuous in parts. A variety of vesicles, 90-450 nm in diameter, were scattered among the tonofilament bundles. Some of these contained needle-like crystals that were considered to be initial calcification sites in ghost cells. These vesicles presented morphological similarities to matrix vesicles, and it is therefore suggested that matrix vesicle-like structures are deeply involved with initiation of calcification of ghost cells in COC.
Toshiaki Hoteiya, Eiji Hayashi, Kazuhito Satomura, Nobuyuki Kamata and Masaru Nagayama : Expression of E-cadherin in oral cancer cell lines and its relationship to invasiveness in SCID mice in vivo, Journal of Oral Pathology & Medicine, 28, 3, 107-111, 1999.
(要約)
We examined the expression of E-cadherin in nine oral cancer cell lines. HSC-4, NA, ZA, HOC927 and Ca9-22 cells strongly expressed E-cadherin [E-CD(++) cell line] and HSC-2 and HSC-3 cells weakly expressed E-cadherin [E-CD(+) cell line]. All the cell lines that expressed E-cadherin were of cuboidal morphology and formed cobblestone colonies. In contrast, TSU and HOC313 cells had spindle shapes, formed dispersed colonies, and were completely negative for E-cadherin [E-CD(-) cell line]. Moreover, all cell lines that expressed E-cadherin showed tumorgenicity in SCID mice, but E-CD(-) cell lines did not show tumorgenicity. The tumors derived from E-CD(+) cell lines invaded deeper into the connective tissues than those from E-CD(++) cell lines. In immunohistochemical analysis, the difference was more marked at the edges of the cancer nests. These results suggest that E-cadherin expression was relevant to the cell forms and the differential grade of cultured cells and that reduced E-cadherin in oral cancer may be associated with invasiveness in vivo.
(キーワード)
cell line / E-cadherin / invasion / oral cancer / SCID mice
Youji Miyamoto, Kunio Ishikawa, Masaaki Takechi, Taketomo Toh, Tetsuya Yuasa, Masaru Nagayama and Kazuomi Suzuki : Histological and compositional evaluations of three types of calcium phosphate cements when implanted in subcutaneous tissue immediately after mixing, Journal of Biomedical Materials Research, 48, 1, 36-42, 1999.
(要約)
To evaluate the soft tissue response of calcium phosphate cement (CPC), consisting of an equimolar mixture of tetracalcium phosphate (TTCP) and dicalcium phosphate anhydrous (DCPA) under conditions close to those encountered in actual surgical procedures, we implanted three types of CPC [conventional CPC (c-CPC), fast-setting CPC (FSCPC), and antiwashout type FSCPC (aw-FSCPC; formerly called nondecay type FSCPC or nd-FSCPC)] subcutaneously in the abdomens of rats immediately (1 min) after mixing. At 1 week after surgery, histological examination and compositional analysis were performed using light microscopy and powder X-ray diffraction (XRD), respectively. The implanted c-CPC was crumbled completely, whereas FSCPC and aw-FSCPC retained their shape. Large vesicles containing copious inflammatory effusion were subcutaneously formed around the c-CPC. Histologically, many foreign-body giant cells were collected around the c-CPC, and moderate inflammatory cell infiltration was observed at 1 week after surgery. In contrast, the FSCPC and aw-FSCPC were covered with a thin layer of granulation tissue that included few giant cells and presented slight inflammatory cell infiltration, and no effusion was observed. The XRD analysis of the c-CPC revealed the presence of some unreacted DCPA even 1 week after implantation, whereas almost no DCPA was found in the FSCPC or aw-FSCPC. In conclusion, it was found that CPC does not always show excellent tissue response. When c-CPC is implanted subcutaneously in rats immediately after mixing, it fails to set and causes a severe inflammatory response. Therefore, the type of CPC should be chosen according to the clinical particulars. CPC should be used in a manner that assures its setting reaction. We recommend the use of FSCPC and aw-FSCPC for surgical applications, such as orthopedics, plastic and reconstructive surgery, and oral and maxillofacial surgery, where the cement might otherwise crumble due to the pressure before setting.
Nobuyuki Kamata, Kazuhiro Yokoyama, Ryoichi Fujimoto, Naohiro Ueda, Eiji Hayashi, Hiroaki Nakanishi and Masaru Nagayama : Growth of normal oral keratinocytes and aquamous cell carcinoma cells in a novel protein-free defined medium, In Vitro Cell. Dev. Biol.-Animal, 35, 10, 635-641, 1999.
(要約)
A novel protein-free synthetic medium was developed for the culture of normal human oral keratinocytes. This medium, designated PFM-7, supports the serial cultivation of primary or secondary normal oral keratinocytes in protein-free, chemically defined conditions. Normal oral keratinocytes in PFM-7 exhibited nearly equal growth in mass culture without noticeable changes in morphology, response to added growth factors, or gene expression of growth factors and their receptors, compared to cells in Keratinocyte-SFM containing epidermal growth factor and bovine pituitary extract. Furthermore, PFM-7 supported the serial subcultivation of human squamous cell carcinoma cells and enabled both normal and malignant oral squamous cells derived from the same patient to grow under the same protein-free defined conditions. These results indicate that PFM-7 can be used for precise investigations of growth mechanisms, cell products, and gene expression associated with carcinogenesis of human epidermal cells.
Masaaki Takechi, Youji Miyamoto, Kunio Ishikiawa, Taketomo Toh, Tetsuya Yuasa, Masaru Nagayama and Kazuomi Suzuki : Initial histological evaluation of anti-washout type fast-setting calcium phosphate cement following subcutaneous implantation, Biomaterials, 19, 22, 2057-2063, 1998.
(要約)
Anti-washout-type fast-setting calcium phosphate cement using chitosan (aw-FSCPC(chi)), conventional CPC (c-CPC), CPC mixed with citric acid (CPC(citric)) and CPC mixed with polyacrylic acid (CPC(acrylic)) were implanted subcutaneously in rats immediately after mixing to shed some light on the understanding of the appearance of excellent tissue response to CPC. CPC(citric) and CPC(acrylic) set quickly, similar to aw-FSCPC(chi), but the former two stopped their transformation to apatitic minerals. The c-CPC, which required a long setting time, was found to be crumbled, but the other CPCs maintained the shape at implantation. The aw-FSCPC(chi) and CPC(citric) showed no inflammatory response whereas c-CPC and CPC(acrylic) showed an inflammatory response one week after implantation. A component of the aw-FSCPC(chi) and c-CPC was an apatitic mineral whereas CPC(citric) and CPC(acrylic) showed no transformation to apatite. We concluded that the non-crumbling property plays a more dominant role in the appearance of excellent tissue response to CPC than the transformation to apatite. Also, a non-crumbling property is not a sufficient condition, but a necessary condition for the appearance of the excellent tissue response to CPC.
Kunio Ishikiawa, Youji Miyamoto, Masaaki Takechi, Taketomo Toh, Masayuki Kon, Masaru Nagayama and Kenzo Asaoka : Non-decay type fast-setting calcium phosphate cement: Hydroxyapatite putty containing an increased amount of sodium alginate, Journal of Biomedical Materials Research, 36, 3, 393-399, 1997.
(要約)
A hydroxyapatite [(HAP) Ca10(PO4)6(OH)2] putty that behaves like a putty or self-curing resin was made by increasing the amount of sodium alginate in non-decay type fast-setting calcium phosphate cement (nd-FSCPC). nd-FSCPC became viscous as the sodium alginate concentration was increased. The best handling properties were obtained when nd-FSCPC contained 8% sodium alginate in its liquid phase. When a 2-kg glass plate was placed on the paste, HAP putty spread to form an area three times that of FSCPC paste. Thus, HAP putty is expected to be easier to use than FSCPC in the filling of bone defects. HAP putty did not decay; in fact, it set within approximately 20 min when immersed in distilled water immediately after mixing. The wet diametral tensile strength value of HAP putty was approximately 12 MPa after 24 h, the same as that for nd-FSCPC containing 0.5% sodium alginate in its liquid phase, or FSCPC that is free from sodium alginate. The elements constituting set HAP putty were examined using powder X-ray diffraction and found to be predominantly apatitic minerals after 24 h. Since the handling properties of a putty or self-curing resin-like cement are very useful in certain surgical procedures, HAP putty made by increasing the sodium alginate concentration in nd-FSCPC is potentially a valuable new biomaterial for use in plastic and reconstructive surgery, as well as oral and maxillofacial surgery.
Youji Miyamoto, Kunio Ishikawa, Masaaki Takechi, Taketomo Toh, Yuki Yoshida, Masaru Nagayama, Masayuki Kon and Kenzo Asaoka : Tissue response to fast-setting calcium phosphate cement in bone, Journal of Biomedical Materials Research, 37, 4, 457-464, 1997.
(要約)
Fast-setting calcium phosphate cement (FSCPC) is a promising new bioactive cement with a significantly short setting time (approximately 5-6 min) compared to conventional calcium phosphate cement (c-CPC) (30-60 min) at physiologic temperatures. As a result of its ability to set quickly, it is applicable in surgical procedures where fast setting is required. In this study, FSCPC was implanted in rat tibiae to evaluate tissue response and biocompatibility. FSCPC was converted to hydroxyapatite (HAP) in bone faster than c-CPC in the first 6 h. By 24 h, significant amounts of both FSCPC and c-CPC had been converted to HAP. The conversion of FSCPC into HAP further proceeded gradually, reaching 100% within 8 weeks. Infrared spectroscopic analysis disclosed the deposition of B-type carbonate apatite, which is a biological apatite contained in human dentin or bone, on the surface of the FSCPC. Histologically, FSCPC showed a tissue response similar to that of c-CPC. A slight inflammatory reaction was observed in the soft tissue apposed to both cements in the early period, and new bone was formed along the surface of the FSCPC at the adjacent bone. However, no resorption of either cement by osteoclasts or macrophages was observed within 8 weeks. We conclude that FSCPC is superior to c-CPC in clinical applications in oral and maxillofacial, orthopedic, plastic, and reconstructive surgery, since it shows a faster setting time and higher mechanical strength in the early period that are required in these surgical procedures, as well as osteoconductivity and excellent biocompatibility similar to that of c-CPC.
Hiroaki Nakanishi, Kouji Yamanouchi, Yuji Gotoh and Masaru Nagayama : The association of platelet-derived growth factor (PDGF) receptor tyrosine phosphorylation to mitogenic response of human osteoblastic cells in vitro, Oral Diseases, 3, 4, 236-242, 1997.
(要約)
The purpose of this study was to make clear the relationship of human osteoblastic cell growth, induced by platelet-derived growth factor (PDGF), to PDGF receptor tyrosine phosphorylation. Osteoblastic cells derived from human maxilla were cultured with human PDGF. The cell growth was evaluated by cell number and DNA synthesis. PDGF receptor tyrosine phosphorylation was detected by immunoblot analysis using anti-PDGF receptor alpha, beta subunits and anti-phosphotyrosine antibodies. Genistein, a tyrosine kinase inhibitor, was added to the culture to investigate the effect on osteoblastic cell growth and PDGF receptor tyrosine phosphorylation induced by PDGF. PDGF stimulated the proliferation of human osteoblastic cells and this effect was synergetic with serum stimulation. DNA synthesis of osteoblastic cells was elevated by PDGF in a dose dependent manner at the minimum concentration of 1 ng ml-1. PDGF also induced PDGF receptor tyrosine phosphorylation within 1 min on osteoblastic cells, and tyrosine phosphorylation occurred on PDGF receptor subunits alpha and beta. Genistein inhibited cell growth and receptor tyrosine phosphorylation, which was induced by PDGF on these cells. In conclusion, human osteoblastic cell growth induced by PDGF is shown to relate to tyrosine kinase of PDGF receptors.
Kunio Ishikawa, Youji Miyamoto, Masaru Nagayama and Kenzo Asaoka : Blast coating method: New method of coating titanium surface with hydroxyapatite at room temperature, Journal of Biomedical Materials Research, 38, 2, 129-134, 1997.
(要約)
When a titanium plate was blasted with hydroxyapatite [HAP; Ca10[x](HPO4)[x](PO4)[6-x](OH)[2-x]] powder at room temperature using an ordinary sandblaster, the surface of the titanium plate was found to be coated with HAP homogeneously and completely. The coated layer was examined with energy dispersive X-ray spectroscopy and X-ray diffraction and was found to be the same as the HAP powder used with respect to composition and crystallographic structure. The coated HAP layer was tightly attached to the surface of the titanium plate, at least at the level of scanning electron microscopy. Interestingly, the HAP particles stuck together at room temperature as if they were sintered. The coating was stable against ultrasonication in water for at least 5 min, and it was difficult to remove by nail scratching. Thus, the bonding strength between the HAP powder and the titanium plate was much higher than that achieved with currently employed room temperature coating processes such as dipping, electrophoretic deposition, and electrochemical deposition. Therefore, the blast coating method is potentially valuable for the fabrication of useful biomaterials for hard tissue replacement.
Youji Miyamoto, Kenji Fujisawa, Masaru Nagayama, Norio Haneji and Yoshio Hayashi : Carcinoma in Pleomorphic Adenoma of the Tongue ; Report of a case, Oral Medicine & Pathology, 1, 2, 111-114, 1996.
(要約)
A carcinoma in pleomorphic adenoma occurring in the tongue of a 47-year-old Japanese woman is reported. The present report is the first to describe a carcinoma in pleomorphic adenoma derived from the posterior lingual glands.
Youji Miyamoto, Kunio Ishikawa, Masaaki Takechi, Masayuki Kon, Masaru Nagayama and Kenzo Asaoka : Non-decay type fast-setting calcium phosphate cement: setting behaviour in calf serum and its tissue response, Biomaterials, 17, 14, 1429-1435, 1996.
(要約)
Non-decay type fast-setting calcium phosphate cement (nd-FSCPC) was evaluated in terms of its setting behaviour in calf serum and its tissue response to investigate the feasibility of its clinical use in surgical applications. Non-decay type cements were prepared by adding various amounts of sodium alginate to the liquid phase of base cements, fast-setting calcium phosphate cement (FSCPC) and conventional calcium phosphate cement (c-CPC). Cement pastes were immersed in serum at 37 degrees C immediately after mixing, and decay behaviour, setting time and mechanical strength were measured to evaluate the possibility of their use in surgical applications. Also, nd-FSCPC was implanted into rat subcutaneous tissue for the initial evaluation of biocompatibility of this potential bioactive cement. nd-FSCPC set in approximately 6-7 min in serum, even when the cement paste was immersed in the serum immediately after mixing, whereas c-CPC and FSCPC decayed completely upon immersion. nd-FSCPC transforms to hydroxyapatite (HA) within 24 h and shows a diametral tensile strength of approximately 4-5 MPa. As a result of transformation to HA, nd-FSCPC showed excellent tissue response when implanted subcutaneously in rats. We conclude that nd-FSCPC has good potential value for use in orthopaedics, plastic and reconstructive surgery, and oral and maxillofacial surgery, where the cement is exposed to blood.
Youji Miyamoto, Masaru Nagayama and Yoshio Hayashi : Verruciform xanthoma occurring within oral lichen planus, Journal of Oral Pathology & Medicine, 25, 4, 188-191, 1996.
(要約)
A verruciform xanthoma occurring within lichen planus on the lateral aspect of the tongue in a 68-year-old Japanese woman is reported. The features suggest that the condition of altered epithelial turnover, as in repeated epithelial desquamation, may cause the verruciform xanthoma.
Kunio Ishikawa, Youji Miyamoto, Masayuki Kon, Masaru Nagayama and Kenzo Asaoka : Non-decay type fast-setting calcium phosphate cement, --- : Composite with sodium alginate ---, Biomaterials, 16, 7, 527-432, 1995.
89.
Koichi Rikimaru, Fumihiro Matsumoto, Eiji Hayashi, Hiroshi Bando and Masaru Nagayama : Evaluation of serum concentration of parathyroid hormone-related protein and its implication in hypercalcemia in squamous cell carcinoma of the head and neck, International Journal of Oral and Maxillofacial Surgery, 24, 5, 365-368, 1995.
(要約)
Hypercalcemia is a common and serious complication associated with squamous cell carcinoma (SCC) and is considered to be caused by a tumor-derived factor, parathyroid hormone-related protein (PTHrP). However, the correlation between serum levels of calcium and PTHrP and the kinetics of PTHrP in SCC of the head and neck is unknown, because the behavior of the circulating form of PTHrP in patients has not been determined. In the present study, the PTHrP concentrations in serum samples from 54 patients (37 with SCC and 17 with benign tumors) were measured by a recently developed radioimmunoassay directed toward the C-terminal region of PTHrP, and the laboratory data including those calcium levels in corresponding samples were reviewed retrospectively. Results showed hypercalcemia in four patients with advanced cancer and in whom elevation of the serum PTHrP concentration was observed simultaneously. The regression analysis also revealed the linear relationship of the calcium level to the PTHrP concentration, but not to the concentration of phosphorus or creatinine, suggesting that monitoring of serum PTHrP level is useful for prediction of hypercalcemia associated with head and neck cancer.
(キーワード)
Adult / Aged / Aged, 80 and over / Calcium / Carcinoma, Squamous Cell / Creatinine / Female / Forecasting / Head and Neck Neoplasms / Humans / Hypercalcemia / Linear Models / Male / Middle Aged / Neoplasm Proteins / Parathyroid Hormone / Parathyroid Hormone-Related Protein / Phosphorus / Proteins / Regression Analysis / Retrospective Studies / Tumor Markers, Biological
(文献検索サイトへのリンク)
● PubMed @ National Institutes of Health, US National Library of Medicine (PMID): 8627105
Eiji Hayashi, Koichi Rikimaru and Masaru Nagayama : Simultaneous production of G-and M-CSF by an oral cancer cell line and the synergistic effects on associated leucocytosis, European Journal of Cancer. Part B, Oral Oncology, 31B, 5, 323-327, 1995.
(要約)
We established a novel cell line, TSU, from a oral cancer patient with marked leucocytosis. The culture supernatant of TSU cells promoted granulocytic colony formation by mouse bone marrow cells, indicating that TSU produced granulocyte-colony stimulating factor (G-CSF). The concentration of G-CSF was 2.45 micrograms/mg protein, measured by enzyme-linked immunosorbent assay (ELISA). The maximum number of colonies induced by TSU culture supernatant was more than that achieved with recombinant human G-CSF (rhG-CSF) and the size of the colonies induced by TSU supernatant was obviously larger than those achieved with rhG-CSF. The activity of TSU supernatant was completely inhibited by antihuman G-CSF and macrophage-colony stimulating factor (M-CSF) antibodies, but was only partially inhibited by antihuman G- or M-CSF antibody alone. These results indicate that not only G-CSF but also M-CSF, both of which could be produced by TSU cells, are involved in causing leucocytosis; the results suggest that the synergistic production of G- and M-CSF could play an important role in the leucocytosis associated with oral cancer.
Hiroyuki Inoue, Hitoshi Miki, Kazushi Oshimo, Katuhiro Tanaka, Yasumasa Monden, Akihiro Yamamoto, Susumu Kagawa, Nobuya Sano, Eiji Hayashi, Masaru Nagayama and Yoshio Hayashi : Familial hyperparathyroidism associated with jaw fibroma: case report and literature review, Clinical Endocrinology, 43, 2, 225-229, 1995.
(要約)
A 53-year-old female suffering from renal stones and hypercalcaemia was diagnosed as having primary hyperparathyroidism caused by hyperplasia of the parathyroid glands. She underwent total parathyroidectomy and implantation of parathyroid tissue. After one year, she underwent surgery for a jaw tumour. The pathological findings indicated it to be a cementifying fibroma. Jackson et al. (1990) reported the familial association of hyperparathyroidism with jaw tumours, and they suggested that this condition represents a new clinical syndrome. We believe that our case belongs to this syndrome.
Youji Miyamoto, Kunio Ishikawa, Hirokazu Fukao, Masahiro Sawada, Masaru Nagayama, Masayuki Kon and Kenzo Asaoka : In vivo setting behavior of fast-setting calcium phosphate cement, Biomaterials, 16, 11, 855-860, 1995.
(要約)
The in vivo setting behaviour of fast-setting calcium phosphate cement (FSCPC) between femoral muscles of the rat was investigated to evaluate the possible value of FSCPC for medical and dental application. Conventional CPC (c-CPC) and FSCPC were implanted between femoral muscles, and various aspects of the setting behaviour such as setting time, mechanical strength and conversion ratio of cement into hydroxyapatite (HAP: Ca10(PO4)6(OH)2) were measured by the Vicat needle method, diametral tensile strength (DTS) measurement, and quantitative powder X-ray diffraction (XRD) analysis, respectively. The setting time of FSCPC in vivo was 5-7 min, in contrast to 48 min for c-CPC. As a result of its fast setting, set specimens of FSCPC showed higher mechanical strength from the initial stage than c-CPC. Higher DTS values were observed in FSCPC than c-CPC implanted after 24 h. Powder XRD analysis revealed faster conversion of FSCPC than c-CPC into HAP, which was responsible both for the faster setting and higher mechanical strength from the initial stage. We concluded, therefore, that FSCPC may be used for a wide range of clinical applications, i.e. fields where fast setting is required such as orthopaedic, plastic and reconstructive, and oral and maxillofacial surgery.
Yasuhiro Bando and Masaru Nagayama : Odontogenic cyst induction by periapical infection in rats, Journal of Oral Pathology & Medicine, 22, 323-326, 1993.
Katsuhiro Yasuda, Kazuhito Satomura and Masaru Nagayama : Behaviour of human ameloblastoma cells in collagen matrix in vitro: an ultrastructural study, Journal of Oral Pathology & Medicine, 20, 438-442, 1991.
106.
Kazuhito Satomura, Kiyotaka Hiraiwa and Masaru Nagayama : Mineralized nodule formation in rat bone marrow stromal cell culture without beta-glycerophosphate, Bone Miner, 14, 1, 41-54, 1991.
107.
Youji Miyamoto, Masaru Nagayama and Yoshio Hayashi : A Cleft Child With Lobulated Tongue and Lingual Hamartoma: Report of a Case, Journal of Oral and Maxillofacial Surgery, 49, 6, 644-646, 1991.
Katsuhiro Yasuda, Kazuhito Satomura, Masaru Nagayama, Yoshio Hayashi and Atsuhito Nakanishi : The behavior of human ameloblastoma tissue in collagen matrix in vitro:an immunohistochemical study, Journal of Oral Pathology & Medicine, 20, 4, 187-190, 1991.
Fumihiro Matsumoto, Youji Miyamoto and Masaru Nagayama : Light-and Electron-Microscopic Observations on the Mandibular Condylar Cartilages in Growing Rats on a Low-Calcium Diet, Acta Anatomica, 142, 1, 41-48, 1991.
(要約)
In order to obtain more insight into the physiologic mechanism of endochondral ossification, histological changes occurring in the mandibular condylar cartilage of growing rats fed on a low-calcium diet were investigated by light and electron microscopy. Twenty-three-day-old rats were fed on a normal diet or a low-calcium diet for 8 weeks. For the histological observations the mandibular condyles were dissected from each animal at 1, 2, 4, 5 and 8 weeks after the initiation of the experiment. Histological changes occurring in the mandibular condylar cartilages of the rats fed on a low-calcium diet were as follows: (1) narrow proliferative and mature cell zones and a wide hypertrophic cell zone, (2) inhibition of development of cell organelles in the mature chondrocytes, (3) decrease in dead cells in the proliferative zone, (4) decrease in glycogen accumulation in the chondrocytes and (5) inhibition of calcification in the extracellular matrix of the hypertrophic cell zone. Additionally at the end of the experimental period, the following findings were observed: (1) appearance of small light cells in the mature cell zone and the hypertrophic cell zone and (2) decrease in proteoglycan granules and appearance of large collagen fibrils in the pericellular region of the hypertrophic cell zone.
(キーワード)
Animals / Bone Development / Calcium, Dietary / Cartilage, Articular / Collagen / Diet / Male / Mandible / Organelles / Rats / Rats, Inbred Strains
(文献検索サイトへのリンク)
● PubMed @ National Institutes of Health, US National Library of Medicine (PMID): 1781238
Kazuhito Satomura and Masaru Nagayama : Ultrasturucture of mineralized nodules formed in rai bone marrow stromal cell culture in vitro, Acta Anatomica, 142, 2, 97-104, 1991.
(要約)
Rat bone marrow stromal cells were cultured in vitro. At days 14-15 of culture, dense clusters of polygonal cells were formed, and they mineralized 2-3 days later. The cells resembling osteoblasts or young osteocytes were histologically observed to be embedded in mineralized or unmineralized extracellular matrices of the nodules. Next, these mineralized nodules were electron-microscopically examined. The osteoblastic cells associated with the nodules had a well-developed rough endoplasmic reticulum, an evident Golgi apparatus and some mitochondria as their intracellular organellae. Some lysosomes and microfilaments were also visible in the cytoplasms. Moreover, some cells protruded cell processes toward the neighboring cells through the extracellular matrix. The extracellular matrix consisted of numerous collagen fibrils which were striated with 60-70 nm axial periodicity and which was similar to bone tissue collagen. A large number of matrix vesicles were scattered among the collagen fibrils in the unmineralized area of the nodules. In contrast, in the mineralized area, numerous matrix vesicles at different stages of maturation and many calcified spherules were observed. That is the mineralization in this culture system was considered to be initiated in association with the matrix vesicles and to progress along the collagen fibrils. From these findings, it was confirmed by the present study that the mineralized nodules formed in this bone marrow stromal cell culture were ultrastructurally similar to bone and that the mineralization also proceeded by going through the normal calcification process. This culture system is considered to be available to study osteogenic differentiation and calcification mechanisms.
(キーワード)
Alkaline Phosphatase / Animals / Bone Marrow Cells / Bone and Bones / Calcification, Physiologic / Cells, Cultured / Male / Microscopy, Electron / Osteoblasts / Osteocytes / Rats / Rats, Inbred F344
(文献検索サイトへのリンク)
● PubMed @ National Institutes of Health, US National Library of Medicine (PMID): 1781261
Yukio Takishita, Kiyotaka Hiraiwa and Masaru Nagayama : Effect of retinoic acid on proliferation and differentiation of cultured chondrocytes in terminal differentiation, The Journal of Biochemistry, 107, 4, 592-596, 1990.
115.
Yuji Gotoh, Kiyotaka Hiraiwa and Masaru Nagayama : In vitro mineralization of osteoblastic cells derived from human bone, Bone and Mineral, 8, 3, 239-250, 1990.
(要約)
Osteoblastic cells were isolated from human maxilla by embedding the bone pieces in collagen gel. The isolated cells could be maintained in monolayer culture up to 50 population doubling levels (PDLs). Both parathyroid hormone (PTH) and prostaglandin E2 (PGE2) increased intracellular cyclic AMP level of the cells. The cells also showed high level of alkaline phosphatase (ALPase) activity and formed mineralized areas in monolayer culture. Electron microscopy demonstrated that these cells were surrounded by numerous well-banded collagen fibrils, among which matrix vesicles were scattered. It was also observed that needle-shaped crystals protruded from some matrix vesicles. These protruded crystals appeared to deposit along the collagen fibrils and a mineralized matrix was formed. The minerals of mineralized matrix mainly consisted of calcium and phosphorus and had the same Ca/P ratio as hydroxyapatite. These results indicate that the cells derived from human bone have characteristics of osteoblastic cells.
Ryoichi Fujimoto, Nobuyuki Kamata, Masayuki Taki, Mayumi Tomonari, Masaru Nagayama and S Yasumoto : Gene expression of telomerase related proteins in human normal oral and ectocervical epithelial cells, Oral Oncology, 39, 5, 445-452, 2003.
(要約)
We analyzed telomerase activities and gene expressions of telomerase components: hTERT, hTR, hTEP1, telomeric repeat binding factors: TRF1, TRF2, and c-myc, Max and Mad in human normal oral and ectocervical epithelial keratinocytes, comparing with those of squamous carcinoma cells and HPV16- or SV40-immortalized cells. Significant telomerase activity and hTERT expression were detected in primary keratinocytes. However, both were dramatically down-regulated during serial passages. The down-regulation of hTERT mRNA was associated with augmented expression of TRF1. Expression of c-myc was slightly decreased, whereas Mad was expressed in parallel with that of hTERT during passages. We also detected an alternate splicing of hTERT transcript in two of four cancer cells and normal aged epithelial cells. These results suggest that the senescence of normal oral and ectocervical keratinocytes is accompanied with up-regulation of TRF1 and down-regulation of telomerase activity due to transcriptional suppression of active form of hTERT in vitro.
Masaru Nagayama : Expression of E-cadherin in oralcancer cell lines and its relationship to invasiveness in SCID mice in vivo, Journal of Oral Pathology & Medicine, 28, 3, 107-111, 1999.
(要約)
We examined the expression of E-cadherin in nine oral cancer cell lines. HSC-4, NA, ZA, HOC927 and Ca9-22 cells strongly expressed E-cadherin [E-CD(++) cell line] and HSC-2 and HSC-3 cells weakly expressed E-cadherin [E-CD(+) cell line]. All the cell lines that expressed E-cadherin were of cuboidal morphology and formed cobblestone colonies. In contrast, TSU and HOC313 cells had spindle shapes, formed dispersed colonies, and were completely negative for E-cadherin [E-CD(-) cell line]. Moreover, all cell lines that expressed E-cadherin showed tumorgenicity in SCID mice, but E-CD(-) cell lines did not show tumorgenicity. The tumors derived from E-CD(+) cell lines invaded deeper into the connective tissues than those from E-CD(++) cell lines. In immunohistochemical analysis, the difference was more marked at the edges of the cancer nests. These results suggest that E-cadherin expression was relevant to the cell forms and the differential grade of cultured cells and that reduced E-cadherin in oral cancer may be associated with invasiveness in vivo.
Eiji Hayashi, Kazuhito Satomura, Keiko Kume, Eiichiro Kitaoka and Masaru Nagayama : Effects of emdogain on human dental papilla-derived cells, 78th General Session of the IADR, Washington, D.C.,
(要約)
1
2.
Reiko Tokuyama, Kazuhito Satomura, Satoshi Tobiume, Kouji Yamanouchi, Keiko Kume, Eichiro Kitaoka, Sachiko Nishisho, Naoko Masuda, Yukiko Hibi and Masaru Nagayama : Melatonin Promotes the Osteoblastic Differentiation and Bone Formation, The ASBMR 24th Annual Meeting, Texas,
(要約)
1
3.
Reiko Tokuyama, Kazuhito Satomura, Maeda Eriko, Eiichiro Kitaoka, Keiko Kume and Masaru Nagayama : Potential Role of Maspinin Rat Endochondral Ossification, 82th IADR, Hawaii,
(要約)
1
4.
Tetsuya Yuasa, Youji Miyamoto, Yukihiro Momota, Nobuyuki Kamata, Masaru Nagayama, Masayuki Kon and Kunio Ishikawa : Effects of sintered apatite, apatite cement on differentiation of human immortalized dental papilla cells, 3rd Asian BioCeramic Symposium(ABC 2003)in conjunction with Hard-Tissue Nano-Biomaterials Symposium 2003, Fukuoka,
(要約)
1
5.
Seiko Tatehara, Youji Miyamoto, Tetsuya Yuasa, Masaaki Takechi, Masaru Nagayama, Masayuki Kon and Kunio Ishikawa : Mechanism for promotion of the differentiation of human cultured osteoblasts by calciumphosphate ceramics, 3rd Asian BioCeramic Symposium(ABC 2003)in conjunction with Hard-Tissue Nano-Biomaterials Symposium 2003, Fukuoka,
(要約)
1
6.
Youji Miyamoto, Seiko Tatehara, Tetsuya Yuasa, Hiroaki Nakanishi, Kenji Fujisawa and Masaru Nagayama : Measurement of the Zygomatic bone and pilot hole technique for safer installation of zygomatic implant, 16th International Conference on Oral and Maxillofacial Surgery(ICOMS), Athens,
(要約)
1
7.
Seiko Tatehara, Youji Miyamoto, Masaaki Takechi, Yukihiro Momota, Tetsuya Yuasa and Masaru Nagayama : Effect of locally applied basic firoblast growth factor on distraction osteogenesis in ovadectomized rats, 16th Intemational Conference on Oral and Maxillofacial Surgery(ICOMS), Athens,
(要約)
1
8.
Reiko Tokuyama, Kazuhito Satomura, Maeda Eriko, Eiichiro Kitaoka, Keiko Kume and Masaru Nagayama : Maspin, a Serine Protease Inhibitor, Regulates the Bone Matrix Maturation by Enhancing the Accumulation of Latent TGF-β, 26th ASBMR, Seattle,
(要約)
1
9.
中西 宏彰, 里村 一人, 藤澤 健司, 長山 勝 : 口腔癌および口腔前痛病変に対する光線力学的療法の応用, 6th Asian Congress on Oral and Maxillofacial Surgery，第49回日本口腔外科学会総会, 千葉,
(要約)
1
10.
Shiho Minamiguchi, Masaaki Takechi, Tetsuya Yuasa, Yukihiro Momota, Seiko Tatehara, Hideyuki Takano, Youji Miyamoto, Kazuhito Satomura and Masaru Nagayama : A basic research on hydroxyapatite-poly(D L-lactide-co glycolic acid)composite scaffolds for bone tissue engineering, The 5th Asian Bio Ceramics Simposium,
(要約)
1
11.
Kazuhito Satomura, Masayuki Kon, Mayumi Tomonari, Masaaki Takechi, Reiko Tokuyama and Masaru Nagayama : Characterization of Osteopetrotic Mandibular cortical bone, Intemational Conference on Oral&Maxillofacial Surgery,
12.
Siho Minamiguchi, Masaaki Takechi, Yukihiro Momota, Youji Miyamoto, Kazuhito Satomura and Masaru Nagayama : A research on the rat subcutaneous tissue of hydroxyapatite-polyD, L-Iactic-co-glycolic acid (PLGA)composite scaffolds for allopatry bone generation., 第1回国際シンポジウム・FDワークショップ「21 世紀の口腔科学が目指すべき方向性」, Awaji, 2007.
(要約)
1
13.
Makoto Fukui, Masami Yoshioka, Kazuhito Satomura, Hiroaki Nakanishi and Masaru Nagayama : Specific Visible Light Irradiation Inhibits the Growth of Porphyromonas gingivalis., 84th General Session & Exhibition of the International Association for Dental Research, Brisbane, Jun. 2006.
14.
Eriko Maeda, Kazuhito Satomura, Reiko Tokuyama, Keiko Kudoh, Yasuhum Yamasaki and Masaru Nagayama : Induced odontogenic differentiation of mouse bone marrow stromal cells., 84th IADR, Jun. 2006.
15.
Reiko Tokuyama, Kazuhito Satomura, Masaaki Taechi, Tetsuya Yuasa, Keiko Kudoh, Seiko Tatehara, Hideyuki Takano, Hiroaki Nakanishi, Eriko Maeda and Masaru Nagayama : Usefulness of self-drilling type alveolar bone screws form mandibular fractures., 84th IADR, Brisbane, 2006.
16.
Yukihiro Momota, Youji Miyamoto, K Ishikawa, Masaaki Takechi, H Takano and Masaru Nagayama : Enhancing Effects on Aggregation of Platelets by Hydroxyapatite Putty as a Topical Hemostatic Agent for Bone, The First International Conference on Mechanics of Biomaterials and Tissues, hawaii, Dec. 2005.
17.
Kenji Fujisawa, Youji Miyamoto, Eiji Yamauchi, Masaaki Takechi, Yukihiro Momota, Tetsuya Yuasa, Seiko Tatehara and Masaru Nagayama : Immediate functional loading of Branemark system implants: One year clinical follow-up study, International Journal of Oral & Maxillofacial Surgery, 34, supplement 1, 129, Aug. 2005.
18.
Kazuhito Satomura, Masayuki Kon, M Tomonori, Masaaki Takechi, Reiko Tokuyama and Masaru Nagayama : CHARACTERIZATION OF OSTEOPETROTIC MANDIBULAR CORTICAL BONE, Oral &Maxillofacial Surgery, 34, 1, 138, Austria, Aug. 2005.
19.
Masaaki Takechi, Yukihiro Momota, Youji Miyamoto, Kazuhito Satomura, Kenji Fujisawa and Masaru Nagayama : Effect of FGF-2 and Melatonin on the promotion of Osseogenesis around Titanium implants., First International Conference on Mechanics of Biomaterials &Tissues, 2005.
(要約)
1
20.
Yukihiro Momota, Youji Miyamoto, Ishikawa Kunio, Masaaki Takechi, Takano Hideyuki and Masaru Nagayama : Enhancing effects aggregation of platelets by hydroxyapatite putty as a topieal hemontatie agent for bone., First International Conference on Mechanics of Biomaterials&Tissues, 2005.
(要約)
1
21.
Seiko Tatehara, Masaaki Takechi, Yukihiro Momota, Tetsuya Yuasa, Minamiguchi Siho and Masaru Nagayama : Fabrication and characterization of Porous Alginate/Chitosan/Hydroxyapatite(HAP) composite scaffold, The 5th Asian Bio Ceramics Simposium, Hokkaido, 2005.
(要約)
1
22.
Reiko Tokuyama, Kazuhito Satomura, E Maeda, E Kitaoka, Keiko Kume and Masaru Nagayama : Maspin,a Serine Protease Inhibitor,Regulates the Bone Matrix Maturation by Enhancing the Accumulation of Latent TGF-beta, Journal of Bone and Mineral Research, 19, suppl 1, S358, Seattle, Oct. 2004.
23.
湯淺 哲也, 大下 修弘, 鎌田 伸之, 江口 覚, 舘原 誠晃, 里村 一人, 長山 勝 : 顎裂閉鎖術を行った精神発達遅滞患者の 1例, 6th Asian Congress on Oral and Maxillofacial Surgery，第49回日本口腔外科学会総会, 千葉, 2004年10月.
24.
Yukihiro Momota, Youji Miyamoto, Kunio Ishikawa, Masaaki Takechi, Tetsuya Yuasa, Seiko Tatehara and Masaru Nagayama : Effects of neutral sodium hydrogen phosphate on the setting property and hemostatic ability of hydroxyapatite putty as a local hemostatic agent for bone, Journal of Biomedical Materials Research. Part B, Applied Biomaterials, 69B, 1, 99-103, Apr. 2004.
(要約)
Hydroxyapatite (HAP) putty has been reported to have good hemostatic ability and excellent biocompatibility. Although the setting reaction of HAP putty and resulting transformation to HAP is the reason for this excellent biocompatibility, it also limits the handling period. In this study, the relationship between the setting reaction of HAP putty and its hemostatic ability was investigated, where neutral sodium hydrogen phosphate concentration and post-preparation time were used as indexes. A higher concentration of neutral sodium hydrogen phosphate was found to result in decreased hemostatic ability. The hemostatic ability of HAP putty decreased with time after its preparation; thus it was important to use HAP putty within 10 min after its preparation. The adhesive strength of HAP putty to bone increased with time. Therefore reliable hemostasis can be expected with HAP putty. Although the limited handling time is a drawback, HAP putty is thought to have a good potential as a hemostatic agent-it is highly reliable, and has a high hemostatic ability with excellent biocompatibility.
Reiko Tokuyama, Kazuhito Satomura, Eriko Maeda, Eiichiro Kitaoka, Keiko Kume and Masaru Nagayama : Potential role of maspin in rat endochondral ossification, Honolulu, Mar. 2004.
26.
Hiroaki Nakanishi, Kazuhiro Yokoyama, Kazuhito Satomura, Nobuyuki Kamata and Masaru Nagayama : Measurement of photoporphyrin IX enhancement in ALA-PDT with a blue-violet clode laser and fibro-optic spectrometer, Miyazaki, May 2003.
27.
Hiroaki Nakanishi, Kazuhito Satomura, Nobuyuki Kamata and Masaru Nagayama : Measurement of protoporphyrin_ IX enhancement in ALA-PDT with a blue-Violet diode laser and fibro-optic spectrometer, 9th World Congress of The International Photodynamic Association, Miyazaki, May 2003.
28.
Youji Miyamoto, Yukihiro Momota, Masaaki Takechi, Tetsuya Yuasa, Seiko Tatehara, Masaru Nagayama and Kunio Ishikiawa : Effects of Neutral Sodium Hydrogen Phosphate on Setting Property and Hemostatic Ability of Hydroxyapatite Putty as a Local Hemostatic Agent for Bone, 15th International Symposium on Ceramics in Medicine, 240-242, 373-376, Sydney, Dec. 2002.
Sachiko Nishisho, Kazuhito Satomura, Eiichiro Kitaoka, Reiko Tokuyama, Keiko Kume and Masaru Nagayama : An activating Gs-alpha mutation is a common cause of monoostotic fibrous dysplasia and ossifying fibroma of the mandible, San Diego, Mar. 2002.
30.
Yukihiro Momota, Youji Miyamoto, K Ishikawa, Masaaki Takechi, Tetsuya Yuasa, T Toh, Masaru Nagayama and K Suzuki : Evalution of Hydroxyapatite-Putty as a Hemostatic Agent, Proceeding of the 13th Int.Symp.on Ceramics in Medicine, 22-26, 849-852, Bologna, Nov. 2000.
Keiko Kume, Kazuhito Satomura, Kouji yamanouchi, Eiichiro Kitaoka, Satoru Tobiume, Sachiko Nishisho, Naoko Masuda and Masaru Nagayama : Localization of leptin in endochondral ossification of mouse femur, Toronto, Sep. 2000.
32.
Keiko Kume, Kazuhito Satomura, Satoru Tobiume, Eiichiro Kitaoka, Kouji Yamanouchi, Eiji Hayashi and Masaru Nagayama : Emdogain promotes the differentiation of human bone marrow cells, Washington, D.C., Apr. 2000.
33.
Eiichiro Kitaoka, Kazuhito Satomura, Keiko Kume, Satoru Tobiume, Kouji Yamanouchi, Eiji Hayashi and Masaru Nagayama : Establishment of chondrocyte cell lines from SV40 transgenic mice, Washington, D.C., Apr. 2000.
34.
Kazuhito Satomura, Eiji Hayashi, Keiko Kume, Kouji Yamanouchi, Eiichiro Kitaoka, Satoru Tobiume and Masaru Nagayama : Effects of Emdogain on human dental papilla-derived cells, Washington, D.C., Apr. 2000.
35.
Eiichiro Kitaoka, Kazuhito Satomura, Eiji Hayashi, Kouji Yamanouchi, Satoru Tobiume, Keiko Kume and Masaru Nagayama : Establishment and characterization of three chondrocyte cell lines derived from costal cartilage of SV40 large T antigen transgenic mice, St. Louis, MO, USA, Oct. 1999.
36.
Kazuhito Satomura, Eiji Hayashi and Masaru Nagayama : Immunohistochemical localization of non-collagenous priteins in human tooth germ, Vancouver, Canada, Mar. 1999.
37.
Eiji Hayashi, Kazuhito Satomura and Masaru Nagayama : Three-dimensional in vitro culture of human dental papilla-derived cells, Vancouver, Canada, Mar. 1999.
38.
Kouji Yamanouchi, Kazuhito Satomura, Yuji Gotoh, Eiichiro Kitaoka, Keiko Kume and Masaru Nagayama : In vivo bone formation by human osteoblastic cells culture with collagen sponge in vitro, San Francisco, Dec. 1998.
39.
Eiji Hayashi, Kazuhito Satomura, Eiichiro Kitaoka, Toshiaki Hoteiya and Masaru Nagayama : Receptor tyrosine kinase expression in human dental papilla-derived cells, Nice, France, Jun. 1998.
40.
Masaaki Takechi, Youji Miyamoto, Kunio Ishikawa, Kenzo Asaoka and Masaru Nagayama : Effects of antibiotics addition on the basic properties of nd-FSCPC, Journal of Dental Research, 76, Spec, 242, Orlando, Mar. 1997.
41.
Youji Miyamoto, Kunio Ishikawa, Masaaki Takechi, Masayuki Kon, Kenzo Asaoka and Masaru Nagayama : Basic properties of calcium phosphate cement containing collagen, Journal of Dental Research, 76, Spec, 243, Orlando, Mar. 1997.
42.
Kunio Ishikawa, Youji Miyamoto, Masaaki Takechi, Masayuki Kon, Kenzo Asaoka and Masaru Nagayama : Basic properties and tissue response of hydroxyapatite putty, Journal of Dental Research, 76, Spec, 150, Orlando, Mar. 1997.
43.
Eiji Hayashi, Kazuhito Satomura, Toshiaki Hoteiya, Kikuji Yamashita and Masaru Nagayama : Isolation and characterization of human dental papilla-derived cells, Orlando, FL, USA, Mar. 1997.
44.
Youji Miyamoto, Kunio Ishikawa, Masaaki Takechi, Masayuki Kon and Masaru Nagayama : Soft tissue responses of calcium phosphate cements, Proceedings of the 9th International Symposium on Ceramics in Medicine, 263-266, Otsu, Nov. 1996.
45.
Masaaki Takechi, Youji Miyamoto, Kunio Ishikawa, Masayuki Kon and Masaru Nagayama : Basic properties of hydroxyapatite putty made with fast-setting calcium phosphate cement and sodium alginate, Proceedings of the 9th International Symposium on Ceramics in Medicine, 235-238, Otsu, Nov. 1996.
46.
Kunio Ishikawa, Youji Miyamoto, Masaaki Takechi, Taketomo Toh, Masayuki Kon, Masaru Nagayama and Kenzo Asaoka : Approaches for bone-replacing calcium phosphate cement, --- Effect of NaHCO3 addition on the properties of calcium phosphate cement ---, Proceedings of the 9th International Symposium on Ceramics in Medicine, 255-258, Otsu, Nov. 1996.
47.
E Hayashi, Takao Hanawa, Kikuji Yamashita, Masaru Nagayama, Kenzo Asaoka, Seiichiro Kitamura, Hidemi Ukai and Kouichi Murakami : Observation of osteogenic cells on calcium-ion-mixing titanium using TEM, Journal of Dental Research, 75, Spec, 396, San Francisco, Mar. 1996.
48.
Kikuji Yamashita, Takao Hanawa, E Hayashi, Seiichiro Kitamura, Kenzo Asaoka, Masaru Nagayama, Hidemi Ukai and Kouichi Murakami : Calcification formed by osteogenic cells cultured on calcium-ion-mixing titanium, Journal of Dental Research, 75, Spec, 309, San Francisco, Mar. 1996.
49.
H Fukao, Youji Miyamoto, M Sawada, Masaru Nagayama, Masayuki Kon, Kunio Ishikawa and Kenzo Asaoka : In vivo reactions of functionally gradient ceramic calcium phosphate, 3rd World Congress for Oral Implantology, Yokohama, Apr. 1994.
Fumihiro Matsumoto, Teruaki Ishikawa, Hisahiro Takeuchi, Kenji Fujisawa, Hidehiko Hosoki, Masaru Hada, Masanori Nakano and Masaru Nagayama : Research on the actual application of the TMD reporting system of Tokushima University Hospital, Journal of the Japanese Society for the Temporomandibular Joint, 19, 1, 81, Jul. 2006.