Tsuyoshi Takato

Tokyo Medical University, Edo, Tōkyō, Japan

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Publications (265)613.31 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: [Background] A gelatin sponge with slowly releasing basic fibroblast growth factor (b-FGF) enhances chondrogenesis. This study investigated the optimal amount of basic fibroblast growth factor (b-FGF) in gelatin sponges to fabricate engineered cartilage. [Material and Methods] b-FGF (0, 10, 100, 500, 1000 and 2000μg/cm3)-impregnated gelatin sponges incorporating β-tri-calcium-phosphate (β-TCP) were produced. Chondrocytes were isolated from the auricular cartilage of C57B6J mice and expanded. The expanded auricular chondrocytes (10x106cells/cm3) were seeded onto the gelatin sponges, which served as scaffolds. The construct assembly was implanted in the subcutaneous space of mice through a syngeneic fashion. Thereafter, constructs were retrieved at 2, 4 or 6 weeks. [Results]Morphology: The size of implanted constructs was larger than the size of the scaffold with 500, 1000 and 2000μg/cm3 b-FGF-impregnated gelatin sponges incorporating β-TCP at 4 weeks and 6 weeks after implantation.  The weight of the constructs increased roughly proportional to the increase in volume of the b-FGF-impregnated scaffold at 2weeks, 4weeks and 6weeks after implantation, except in the 2000μg/cm3 b-FGF-impregnated constructs group. Histological examination: Extracellular matrix in the center of the constructs was observed in gelatin sponges impregnated with more than 100μg/cm3 b-FGF at 4 weeks after implantation. The areas of cells with abundant extracellular matrix were positive for cartilage-specific marker type 2 collagen in the constructs. ○4Protein assay: Glycosaminoglycan and collagen type 2 expression were significantly increased at 4 and 6 weeks upon implantation of gelatin sponges impregnated with more than 100μg/cm3 b-FGF. At 6weeks after implantation, the ratio of type 2 collagen to type 1 collagen in constructs impregnated with 100μg/cm3 or more b-FGF was higher than that in mice auricular cartilage. [Conclusion] Gelatin sponges impregnated with more than 100μg/cm3 b-FGF incorporating β-TCP with chondrocytes (10x106cells/cm3) can fabricate engineered cartilage at 4 weeks after implantation.
    Tissue engineering. Part A. 10/2014;
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    ABSTRACT: We used a piece of costal cartilage as a cartilaginous strut to correct the upturned nasal tip in patients with bilateral cleft lip. The grafted cartilage provides more definition of the tip and improves the obtuse nasolabial angle. Neither the septal cartilage nor the ear cartilage has enough strength to shape the tip. This method of correction has consistently produced favorable, long-lasting results in adults and has improved the contour of the nasal tip in younger patients.
    The Journal of craniofacial surgery. 09/2014; 25(5):e443-e445.
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    ABSTRACT: Pleomorphic adenoma is the most common benign parotid gland tumor. Although its local recur-rence rate is known to be high, the recurrence extending to the cervical region is rare. Here we report a case of a young female (25 years old) with pleomorphic adenoma of the parotid gland which showed multiple recurrences through facial to cervical regions over a span of eight years. We also discuss how this benign tumor with a high recurrence rate has been treated in other cases, and how it should be treated.
    Open Journal of Stomatology 08/2014; 4(4):441-445.
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    ABSTRACT: Pluripotent stem cells are a promising tool for mechanistic studies of tissue development, drug screening, and cell-based therapies. Here, we report an effective and mass-producing strategy for the stepwise differentiation of mouse embryonic stem cells (mESCs) and mouse and human induced pluripotent stem cells (miPSCs and hiPSCs, respectively) into osteoblasts using four small molecules (CHIR99021 [CHIR], cyclopamine [Cyc], smoothened agonist [SAG], and a helioxanthin-derivative 4-(4-methoxyphenyl)pyrido[4',3':4,5]thieno[2,3-b]pyridine-2-carboxamide [TH]) under serum-free and feeder-free conditions. The strategy, which consists of mesoderm induction, osteoblast induction, and osteoblast maturation phases, significantly induced expressions of osteoblast-related genes and proteins in mESCs, miPSCs, and hiPSCs. In addition, when mESCs defective in runt-related transcription factor 2 (Runx2), a master regulator of osteogenesis, were cultured by the strategy, they molecularly recapitulated osteoblast phenotypes of Runx2 null mice. The present strategy will be a platform for biological and pathological studies of osteoblast development, screening of bone-augmentation drugs, and skeletal regeneration.
    Stem cell reports. 06/2014; 2(6):751-60.
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    ABSTRACT: Recently, there have been remarkable advances in regenerative medicine, and almost all disorders of the oral and maxillofacial region could be research targets of regenerative medicine. Meanwhile, treatment in this region has been well established using biomaterials, prostheses, and microsurgery. Therefore, to surpass such a conventional approach as an alternative, regenerative medicine should take an approach of being less invasive and/or more effective. In this report, we present our preclinical and clinical research on bone and cartilage regenerative medicine in the oral and maxillofacial region. Regarding bone regenerative medicine, we have tried to develop artificial bone that would maximize bone formation at the transplanted site, but would subsequently be replaced by autologous bone. We have made custom-made artificial bone (CT-Bone) using alpha-tricalcium phosphate (α-TCP) particles and an ink-jet printer, and have conducted clinical research and trials on 30 patients. To develop tissue-engineered cartilage with proper three-dimensional (3D) morphological form and mechanical strength, we have optimized the culture medium of chondrocytes and the scaffold. Following a preclinical study confirming efficacy and safety, we have conducted clinical research in three patients with nasal deformity associated with cleft lip and palate, and are now starting multicenter clinical research.
    International Journal of Oral Science 05/2014; · 2.72 Impact Factor
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    ABSTRACT: Odontogenic myxoma is a benign odontogenic tumor with locally aggressive behavior, and is relatively rare in the oral cavity. There are currently no clear surgical management guidelines for odontogenic myxoma, and a variety of approaches may be used. This study evaluated the literature concerning the surgical management of odontogenic myxoma, and reports the long-term outcome of a case managed by using a more conservative surgical approach. We managed a 40-year-old Japanese man with odontogenic myxoma in the right mandible by enucleation and curettage, a relatively conservative approach that has proved to have been justified by a lack of recurrence over 10 years. Our strategy was compared with others reported in the literature, which was identified by a PubMed search using the term "odontogenic myxoma". Articles without full text or with missing data were excluded. The age and sex of patients, the tumor location (maxilla/mandible), treatment (conservative/radical), recurrence, and follow-up period were compared in the reported cases that we evaluated. From the initial 211 studies identified, 20 studies qualified as mandibular cases of odontogenic myxoma. Recurrence was reported in three cases that had been treated with a more conservative surgical approach. Enucleation and curettage has proved an effective approach in several cases in ours there has been no recurrence more than 10 years after surgery but the risk of recurrence appears to be higher. We discuss the important factors that must be considered when determining the correct management approach to odontogenic myxoma.
    BMC Research Notes 04/2014; 7(1):214.
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    ABSTRACT: Rapid and efficient animal models are needed for evaluating the effectiveness of many new candidate bone regenerative materials. We developed an in vivo model screening for calvarial bone regeneration in lipopolysaccharide (LPS)-treated mice, in which materials were overlaid on the periosteum of the calvaria in a 20 min surgery and results were detectable in 1 week. Intraperitoneal LPS injection reduced spontaneous bone formation, and local application of basic fibroblast growth factor (bFGF) increased the bone-forming activities of osteoblasts. A novel synthetic collagen gel, alkali-treated collagen (AlCol) cross-linked with trisuccinimidyl citrate (TSC), acted as a reservoir for basic substances such as bFGF. The AlCol-TSC gel in conjunction with bFGF activated osteoblast activity without the delay in osteoid maturation caused by bFGF administration alone. The AlCol-TSC gel may slow the release of bFGF to improve the imbalance between osteoid formation and bone mineralization. These findings suggest that our model is suitable for screening bone regenerative materials and that the AlCOl-TSC gel functions as a candidate reservoir for the slow release of bFGF.
    Journal of Materials Science Materials in Medicine 02/2014; · 2.14 Impact Factor
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    ABSTRACT: Basic fibroblast growth factor (b-FGF) is a very effective growth factor that induces the proliferation of chondrocytes. This study aimed to investigate whether intra-tracheally-injected b-FGF solution promotes the growth of tracheal cartilage. Group 1: 500μl of distilled water was injected at the posterior wall of the cervical trachea of New Zealand white rabbits by using a tracheoscope (n=5). Group 2: 100μg/500μl of b-FGF solution was injected at the posterior wall of the cervical trachea (n=5). Group 3: Biodegradable gelatin hydrogel microspheres incorporating 100μg/500μl of b-FGF solution were injected at the posterior wall of the cervical trachea (n=5). All animals were sacrificed 4weeks later, and the outer diameter and luminal area of the cervical trachea at the site of b-FGF injection were measured. The cervical tracheas in the two b-FGF injection groups were spindle-shaped and had a maximum diameter at the injection site. The median outer diameter of the cervical trachea in Groups 1, 2, and 3 was 7.3, 8.0, and 8.0mm, respectively, showing a significant difference among Groups 1, 2, and 3 (P=0.04). The median luminal area in Groups 1, 2, and 3 was 27.4, 29.4, and 32.1mm(2), respectively. The ad hoc test showed a marginally significant difference only between groups 1 and 3 (p=0.056). Intra-tracheal injection of slowly released b-FGF enlarged the tracheal lumen.
    Journal of Pediatric Surgery 02/2014; 49(2):296-300. · 1.38 Impact Factor
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    ABSTRACT: We created sugar-based cross-linkers for precise chemical cross-linking of atelocollagen to form a stable hydrogel micro-environment for 3-dimentional (3-D) cell culture. Cross-linkers were synthesized by partially oxidizing glucose, fructose, maltose, sucrose, or raffinose with periodate. The partial oxidization of sugar generated multiple aldehydes in the molecule, which acted as multifunctional cross-linkers, allowing atelocollagen to form chemical hydrogels. The cross-link reaction of atelocollagen was competitively suppressed by the addition of amino acid-rich medium, enabling flexible control of 3-D molecular density in the acquired hydrogel. To evaluate structural stability, ultrasonic stress was loaded onto the acquired hydrogel and sequential measurement of water content revealed that the cross-linking considerably stabilized the hydrogel structure. The effectiveness of the atelocollagen hydrogel as a 3-D culture scaffold was analyzed by embedding and culturing endothelial cells or cardiomyocytes in it. Endothelial cells formed 3-D capillary-like structures at 12 h, and cardiomyocytes formed a beating 3-D netlike structure by 7 days. These findings suggest that cross-linked atelocollagen hydrogel effectively functions as a stable scaffold in 3-D culture.
    Journal of Biomedical Materials Research Part A 02/2014; · 2.83 Impact Factor
  • Yuko Fujihara, Tsuyoshi Takato, Kazuto Hoshi
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    ABSTRACT: To obtain stable outcomes in regenerative medicine, controlling inflammatory reactions is a requirement. Previously, auricular chondrocytes in tissue-engineered cartilage have been shown to express factors related to immune privilege including Fas ligand (FasL) in mice. Since elucidation of mechanism on immune privilege formed in cartilage regeneration may contribute to suppression of excessive inflammation, in the present study, we investigated the function of FasL and induction of immune privilege in tissue-engineered cartilage using a mouse subcutaneous model. When co-cultured, auricular chondrocytes of FasL-dysfunctional mice, C57BL/6JSlc-gld/gld (gld), induced less cell death and apoptosis of macrophage-like cells, RAW264, compared with chondrocytes of C57BL/6 mice (wild), suggesting that FasL on chondrocytes could induce the apoptosis of macrophages. Meanwhile, the viability of chondrocytes was hardly affected by co-cultured RAW264, though the expression of type II collagen was decreased, indicating that macrophages could hamper the maturation of chondrocytes. Tissue-engineered cartilage containing gld chondrocytes exhibited greater infiltration of macrophages, with less accumulation of proteoglycan than did wild constructs. Analysis of the co-culture medium identified G-CSF as an inducer of FasL on chondrocytes, and G-CSF-treated tissue-engineered cartilage showed less infiltration of macrophages, with increased formation of cartilage after transplantation. The interactions between chondrocytes and macrophages may increase G-CSF secretion in macrophages and induce FasL on chondrocytes, which in turn induce the apoptosis of macrophages and suppress tissue reactions, promoting the maturation of tissue-engineered cartilage. These findings provide scientific insight into the mechanism of autologous chondrocyte transplantation, which could be applied as a novel strategy for cartilage tissue engineering. Stem Cells 2014.
    Stem Cells 01/2014; · 7.70 Impact Factor
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    ABSTRACT: In this study, we developed a new method to stimulate osteogenic differentiation in tissue-nonspecific alkaline phosphatase (TNAP)-positive cells liberated from human induced pluripotent stem cells (hiPSCs)-derived embryoid bodies (EBs) with 14 days long TGF-β/IGF-1/FGF-2 treatment. TNAP is a marker protein of osteolineage cells. We analyzed and isolated TNAP-positive and E-cadherin-negative nonepithelial cells by fluorescence-activated cell sorting. Treating the cells with a combination of transforming growth factor (TGF)-β, insulin-like growth factor (IGF)-1, and fibroblast growth factor (FGF)-2 for 14 days greatly enhanced TNAP expression and maximized expression frequency up to 77.3%. The isolated cells expressed high levels of osterix, which is an exclusive osteogenic marker. Culturing these TNAP-positive cells in osteoblast differentiation medium (OBM) led to the expression of runt-related transcription factor 2, type I collagen, bone sialoprotein, and osteocalcin (OCN). These cells responded to treatment with activated vitamin D3 by upregulating OCN. Furthermore, in OBM they were capable of generating many mineralized nodules with strong expression of receptor activator of NF-kappaB ligand and sclerostin (SOST). Real-time RT-PCR showed a significant increase in the expression of osteocyte marker genes, including SOST, neuropeptide Y, and reelin. Scanning electron microscopy showed dendritic morphology. Examination of semi-thin toluidine blue-stained sections showed many interconnected dendrites. Thus, TNAP-positive cells cultured in OBM may eventually become terminally differentiated osteocyte-like cells. In conclusion, treating hiPSCs-derived cells with a combination of TGF-β, IGF-1, and FGF-2 generated TNAP-positive cells at high frequency. These TNAP-positive cells had a high osteogenic potential and could terminally differentiate into osteocyte-like cells. The method described here may reveal new pathways of osteogenesis and provide a novel tool for regenerative medicine and drug development.
    PLoS ONE 01/2014; 9(6):e99534. · 3.53 Impact Factor
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    ABSTRACT: Hedgehog (Hh) signaling plays important roles in various development processes. This signaling is necessary for osteoblast formation during endochondral ossification. In contrast to the established roles of Hh signaling in embryonic bone formation, evidence of its roles in adult bone homeostasis is not complete. Here we report the involvement of Gli1, a transcriptional activator induced by Hh signaling activation, in postnatal bone homeostasis under physiological and pathological conditions. Skeletal analyses of Gli1+/- adult mice revealed that Gli1 haploinsufficiency caused decreased bone mass with reduced bone formation and accelerated bone resorption, suggesting an uncoupling of bone metabolism. Hh-mediated osteoblast differentiation was largely impaired in cultures of Gli1+/- precursors, and the impairment was rescued by Gli1 expression via adenoviral transduction. In addition, Gli1+/- precursors showed premature differentiation into osteocytes and increased ability to support osteoclastogenesis. When we compared fracture healing between wild-type and Gli1+/- adult mice, we found that the Gli1+/- mice exhibited impaired fracture healing with insufficient soft callus formation. These data suggest that Gli1, acting downstream of Hh signaling, contributes to adult bone metabolism, in which this molecule not only promotes osteoblast differentiation but also represses osteoblast maturation toward osteocytes to maintain normal bone homeostasis.
    PLoS ONE 01/2014; 9(10):e109597. · 3.53 Impact Factor
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    ABSTRACT: We report herein on use of a percutaneous zygomatic arch osteotomy that is simple, safe, and less invasive than conventional methods on patients in whom protrusion deformity of the zygoma following facial fracture surgery. Even though osteotomy is performed percutaneously, this technique entails a lower risk of facial nerve damage compared with other extraoral approaches, and the method is both minimally invasive and simple. No serious postoperative side effects were observed and the facial symmetry was achieved.
    Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology. 01/2014; 26(2):138–141.
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    ABSTRACT: Purpose Our objective was to investigate the feasibility of engineering cartilage on the esophagus layer and outside the esophagus. Moreover, we investigated the feasibility of tracheoplasty with cartilage engineered on the esophagus in rabbits. Methods Chondrocytes were isolated from auricular cartilages. 1. Engineered cartilage formation by histological findings on/into the esophageal layer was compared with that of injectable scaffold and preformed scaffold with chondrocytes. 2. Chondrocytes adhered to gelatin + vicryl mesh™ and b-FGF, were implanted on the outer esophageal surface. Four weeks after seeding, we found that cartilage was implanted in the midposterior portion of the cervical trachea (n = 5), and it was retrieved 8 weeks after seeding. Results 1. A gelatin sponge incorporating β-TCP with vicryl mesh™ showed the best performance for fabricating engineered cartilage on the outer side of the esophagus. 2. Two of 5 rabbits died due to obstructed esophagus. Cartilage engineered outside the esophagus by a composite scaffold as the main material in the gelatin sponge, maintained the airway structure for up to 1 month after implantation. Tracheal epithelial regeneration occurred in the internal lumen of this engineered cartilage. Conclusion Tracheoplasty with cartilage engineered outside the esophagus may be useful for reconstructing airways.
    Journal of Pediatric Surgery. 01/2014;
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    ABSTRACT: A patient who had a primary undifferentiated high-grade pleomorphic sarcoma/malignant fibrous histiocytoma that apparently arose in the mandible, but showed uncertain differentiation on histopathological examination, is described. Our regimen, a combination of pre- and postoperative chemotherapy and surgical resection, produced a good outcome.
    International Journal of Oral Science 01/2014; · 2.72 Impact Factor
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    ABSTRACT: Previous reports suggest that the most common location of the odontomas are in the maxilla. Among the ectopic odontoma, the nasal ectopic odontomas are rare, and are usually asymptomatic. Here, we present a rare case of an ectopic complex odontoma in the lower nasal turbinate causing nasal obstruction and bleeding, which was removed surgically. A 33-year-old male patient presented to our hospital with chief symptoms of nasal obstruction and bleeding from the nose. The Computed Tomography (CT) image of head and neck showed an irregular radio opaque mass in the lower nasal turbinate. The endoscopic examination revealed part of the tumor resembling toothlet. From the above findings, clinical diagnosis of odontoma was made. Histological examination of the mass confirmed the diagnosis of complex odontoma. The symptoms of obstruction and bleeding was averted by surgical removal of the mass.
    Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology. 01/2014; 26(3):347–350.
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    ABSTRACT: Patients infected with the human immunodeficiency virus (HIV) are at risk of developing malignancies and have an increased susceptibility to infection. HIV-associated Burkitt lymphoma (BL) is relatively rare in developed countries, but remains prevalent in developing counties and is sometimes compounded by the fact that patients may be unaware that they are HIV-positive. A 37-year-old Japanese man was referred to our department for diagnosis and management of submandibular swelling. He was unaware that he was HIV-positive at the initial visit. Here, we describe our diagnostic approach, in which we used hematological and immunological investigations, biopsy, fluorescence-activated cell sorting and fluorescence in situ hybridization to confirm the diagnosis of HIV-associated BL. The patient has no risk factors for HIV infection, and the source of infection remains unclear. In this case, submandibular swelling was the first clinical sign of pathology and the patient's HIV-positive status only became evident later. It is highly likely that BL was triggered by HIV infection.
    BMC Research Notes 12/2013; 6(1):557.
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    ABSTRACT: Craniofacial surgery occasionally results in sores and necrosis of the facial skin because of pressure from surgical instruments. During surgical treatment of mandibular condylar process fractures, the main mandibular fragment is routinely retracted downward using a wire to achieve a satisfactory anatomic reduction. This procedure may injure the facial skin. This potential complication is easily overlooked by medical staff, but it is easily preventable. We herein describe a method of using a rubber tube to avoid causing pressure sores of the facial skin during surgical treatment of mandibular condylar process fractures.
    The Journal of craniofacial surgery 11/2013; 24(6):e604-6. · 0.81 Impact Factor
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    ABSTRACT: Extensive squamous cell carcinoma involving the skin of the upper lip, nasal ala, and cheek is relatively rare. Although numerous reconstruction techniques for the midface including lip, nose, and cheek have been described in the literature, reconstruction of large defects in this area continues to be challenging, as it is difficult to obtain satisfactory results with single-stage surgery. This case report concerns a 53-year-old woman with squamous cell carcinoma extending from the upper lip to the alar base and the cheek. It describes a step-by-step surgery undertaken according to defined regional aesthetic units of the face using several reconstruction methods, including a microvascular free flap, forehead flap, and conchal cartilage graft, rather than multistage reconstruction surgeries after first immediate reconstruction. Satisfactory functional and aesthetic results were achieved despite the extensive facial defects.
    Oral surgery, oral medicine, oral pathology and oral radiology. 10/2013;
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    ABSTRACT: Objective : To clarify the short- and long-term effects of maxillary protraction (MP) in mixed dentition in patients with unilateral cleft lip and palate (UCLP). Design : Retrospective study. Setting : University of Tokyo Hospital. Patients and Intervention : Eleven Japanese patients with UCLP in mixed dentition were treated with MP and followed up until the completion of growth. Multibracket treatment had been performed after MP treatment in all patients. Main Outcome Measure : Lateral cephalograms taken before and after MP and after completion of growth were used. Posterior and anterior vertical reference lines (PV, AV) were used to measure the horizontal movements of point A, pogonion, and maxillary first molar (U6). SNA, SNB, ANB, maxillary and mandibular length, mandibular plane angle, Wits value, upper incisor inclination, overjet, and overbite were also measured. Results : Large variation was found in the effects of MP, and five patients eventually required orthognathic surgery. In average change with MP, the maxilla showed favorable forward growth. Point A had moved forward from PV but not AV. The mandible rotated backward. However, ANB and the Wits value did not improve. U6 moved forward, and the overjet improved. After MP, the skeletal Class III relationship became severe. Conclusions : MP was effective as an early treatment for UCLP patients. However, its effects showed large variation and were in conflict with facial growth. Conscientious explanation of the expected effects and associated problems should be given to the patients/parents before its application.
    The Cleft Palate-Craniofacial Journal 09/2013; · 1.24 Impact Factor

Publication Stats

2k Citations
613.31 Total Impact Points

Institutions

  • 1988–2014
    • Tokyo Medical University
      • Department of Oral and Maxillofacial Surgery
      Edo, Tōkyō, Japan
  • 1987–2014
    • The University of Tokyo
      • • Department of Tissue Engineering
      • • Faculty & Graduate School of Medicine
      • • Center for Health Service
      • • Division of Sensory and Motor System Medicine
      • • Department of Oral-Maxillofacial Surgery, Dentistry and Orthodontics
      • • Department of General Surgery
      Edo, Tōkyō, Japan
  • 2013
    • National Institute for Materials Science
      • International Center for Materials Nanoarchitectonics (MANA)
      Tsukuba, Ibaraki-ken, Japan
  • 2011
    • The Open University of Japan
      Edo, Tōkyō, Japan
    • University Hospital Medical Information Network
      Edo, Tōkyō, Japan
  • 2010
    • Tsurumi University
      • School of Dental Medicine
      Yokohama-shi, Kanagawa-ken, Japan
  • 2007–2008
    • Japan Society for the Promotion of Science
      Edo, Tōkyō, Japan
  • 1986–2008
    • National Cancer Center
      • Endoscopy Division
      Edo, Tōkyō, Japan
  • 2002
    • Kitasato University
      Edo, Tōkyō, Japan
  • 1999
    • Saitama Medical University
      • Department of Reconstructive Surgery
      Saitama, Saitama-ken, Japan
  • 1998
    • Teikyo University Hospital
      Edo, Tōkyō, Japan
    • Nihon University
      • Department of Oral Surgery
      Edo, Tōkyō, Japan
  • 1988–1997
    • Shizuoka Hospital
      Sizuoka, Shizuoka, Japan
  • 1991–1992
    • SickKids
      • Division of Plastic Surgery
      Toronto, Ontario, Canada