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Objective Fibrous dysplasia (FD) is a benign bone disease characterized by fibro-osseous lesions. FD is caused by somatic mutations in the gene, guanine nucleotide-binding protein, alpha stimulating activity polypeptide 1 (GNAS), which encodes the G protein subunit, Gsα. FD manifests early in life, but the growth of lesions usually ceases in adulthood. FD lesions often exhibit somatic mutation mosaicism. In this study, the relationship between lesion growth and mutation prevalence within a lesion was investigated. Design Lesions from five FD patients were characterized by radiographical, histological and immunohistochemical methods. To accurately calculate the prevalence of mutations within lesions, GNAS codon 201 in genomic DNA isolated from fresh surgical FD specimens was sequenced. Results Uniquely, a lesion in one 46-year-old patient was still growing, enabling simultaneous analysis of both stable-old and active-new FD lesions in the same patient. Immunohistochemical analysis indicated that a newer, proximal lesion was growing while an older, distal lesion was not. The mutation prevalence differed between these lesions; it was low in the old and high in the new lesion. Thus, the frequency of mutated cells had decreased in the older lesion. Conclusions This is the first direct evidence for the age-dependent demise of mutated cells in FD, helping to explain why FD lesion growth generally ceases in adulthood.

Objective C-type natriuretic peptide (CNP), a potent stimulator of endochondral ossification, acts through guanylyl cyclase B (GC-B), a subtype of membranous guanylyl cyclase. In previous studies, we revealed that CNP stimulates the longitudinal growth of vertebrae and long bones formed through endochondral ossification in mice. Furthermore, we showed that CNP stimulates endochondral ossification in the craniofacial region and is crucial for midfacial skeletogenesis using cartilage-specific CNP transgenic mice and systemic CNP knockout mice. In the present report, we investigated the effect of increased circulating CNP on craniofacial skeletogenesis in a murine model. Methods We analyzed the craniofacial morphology of transgenic mice in which CNP is expressed under the control of the human serum amyloid P component promoter (SAP-Nppc-Tg mice), resulting in elevated levels of circulating CNP. Next we crossed these SAP-Nppc-Tg mice with CNP knockout mice to clarify whether midfacial hypoplasia in CNP knockout mice will be rescued or not. Results SAP-Nppc-Tg mice exhibited longitudinal overgrowth along the cranial length through endochondral ossification. The midfacial hypoplasia in CNP knockout mice was significantly rescued by increasing circulating CNP level. In addition, the foramen magnum stenosis of CNP knockout mice was significantly ameliorated in the rescued mice. Conclusions Circulating CNP affects cartilage and promotes endochondral ossification in craniofacial region. Systemic administration of CNP might have therapeutic potential not only against midfacial hypoplasia, but also against other aspects of impaired craniofacial skeletal growth, including foramen magnum stenosis, in patients suffering from skeletal dysplasias.

Populations of pluripotent stem cells were isolated from bone marrow, synovial fluid, adult dental pulp, and exfoliated deciduous teeth and their multipotentiality properties compared. Osteogenic, chondrogenic, adipogenic, and neurogenic differentiation potentials were examined. Bone marrow mesenchymal stem cells (BMMSCs) and synovial fluid-derived cells (SFCs) showed the highest levels of osteogenesis as expressed by alkaline phosphatase (ALP) activity (0.54±0.094 U/mg protein and 0.57±0.039 U/mg protein, respectively; P=0.60) and by osteocalcin (BGLAP; determined by real-time RT-PCR). SFCs showed the highest levels of chondrogenesis as expressed by ALP activity (1.75±0.097 U/mg protein) and of COL2A1 and COL10A1 by real-time PCR. In terms of adipogenesis, lipid vesicles were observed in the BMMSCs and SFCs. Dental pulp stem cells (DPSCs) and stem cells from human exfoliated deciduous teeth (SHED) exhibited neurogenesis potential, as shown by increases in expression of class III β-tubulin (TUBB3) and microtubule-associated protein 2 (MAP2) on RT-PCR. Variability was found in the differentiation potential corresponding to the tendency of the original tissue to differentiate. It is suggested that the cell type should be selected depending on the regenerative treatment regimen.

Robinow syndrome is very rare and is characterized by congenital anomalies of the head and neck. Symptoms occurring in the head and neck region include osteosclerosis of the skull, midface hypoplasia, cleft palate, and impacted teeth. There is no case report describing oral maxillofacial surgery in Robinow syndrome. We report the case of a 19-year-old female in whom a panoramic radiograph revealed a radiopaque lesion in the right maxillary molar region along with multiple impacted teeth, hypodontia, and retained deciduous teeth in her jaws. Impacted tooth was also present in the radiopaque lesion on the right maxilla. Computed tomography revealed a high-density area on the right maxilla, representing a lesion containing an impacted tooth. The general findings and the presence of impacted teeth indicated symptomatic disease, and biopsy examination confirmed an osteoma. After additional examinations, Robinow syndrome was diagnosed. Tooth extraction was performed under general anesthesia. About 8 months after operation, the wound showed epithelialization and osteoma-like tissue formation was confirmed in the extraction socket. We considered repeated observations to be necessary in this case because of the possibility of recurrence. It is necessary to be aware of the possible diagnosis of Robinow syndrome on the basis of intraoral symptoms after school age.

Purpose: To investigate whether bone regeneration can be accelerated by using a conditioned medium (CM) and guided bone regeneration (GBR) technique. Materials and Methods: CM was harvested from rat bone marrow stromal cells (BMSCs). The components of CM were immobilized using a polylactide-co-glycolide (PLGA) membrane treated with and without 0.5 mol/L sodium hydroxide (NaOH) to elevate the hydrophilicity. Four experimental groups were prepared: PLGA membrane treated with (1) phosphate-buffered saline (PBS; PBS-M), (2) PBS and 0.5 mol/L NaOH (hydrophilic treatment; PBS-HM), (3) CM (CM-M), and (4) CM and 0.5 mol/L NaOH (CM-HM). These experimental membranes were observed using scanning electron microscopy. Proteins derived from BMSCs immobilized on the PLGA membrane were detected with liquid chromatography–tandem mass spectrometry (LC/MS/MS). Cell proliferation and alkaline phosphatase (ALP) activity were measured to analyze the effect of CM on the BMSCs. Experimental membranes were transplanted into a rat calvarial bone defect model. Microcomputed tomography and histologic analyses were performed 4 and 8 weeks after transplantation. Results: The CM derived from BMSCs can be immobilized on the PLGA membrane. Hydrophilic treatment of the PLGA membrane enhanced the amount of CM immobilization. LC/MS/MS analysis showed that the immobilized proteins on the surface of PLGA membrane were extracellular matrix, such as collagen, decorin, and fibronectin. The proteins in the CM, which were released from the PLGA membrane, enhanced cell proliferation and ALP activity in rat BMSCs. Newly formed bone area at the bone defects that had been treated with CM-HM was significantly high compared with those at bone defects treated with the other membranes. Conclusion: The PLGA membrane treated with 0.5 mol/L NaOH and CM promoted bone regeneration in this rat calvarial defect model.

Bernard–Soulier syndrome is characterized by thrombocytopenia, giant platelets, and severe bleeding; although bleeding varies widely, it is usually evident from childhood and requires particular attention during surgeries. We extracted a fractured tooth and performed hemostasis management in a male patient with a Bernard–Soulier syndrome-related severe bleeding tendency after intracerebral hemorrhage. The preoperative platelet count was abnormally low (7 × 10 9 /L). Normal coagulability was observed. After intravenous hydrocortisone administration, he received 10 human leukocyte antigen-matched platelet units. The extraction sites were packed with gelatine sponges and a splint was used for hemostasis. Excellent hemostasis was achieved with minimal human leukocyte antigen-matched platelets.

Congenital thrombocytopenia is a rare, intractable hereditary disease characterized by thrombocytopenia and abnormalities of platelet function. In contrast, idiopathic thrombocytopenic purpura (ITP) is a more frequent thrombocytopenic disease. Furthermore, it is possible that chronic and refractory ITP include congenital thrombocytopenia. We describe a case in which we extracted a tooth and performed hemostasis in an 87-year-old man with a suspected congenital X-linked thrombocytopenia (XLT)-related severe bleeding tendency. XLT is very rare in congenital thrombocytopenia. The patient had a platelet count of 2.0 × 104/μL and received 20 units of platelet concentrate before and after the extraction in liaison with our hematology and oncology department. We have previously reported a model on hemostasis management and extraction of Bernard–Soulier Syndrome (BSS) patients with congenital thrombocytopenia. The extraction sites were packed with gelatin sponges, and sutured, then a splint was used for hemostasis. Excellent hemostasis was achieved with minimal required platelet infusion.

PURPOSE The objective of this study was to histologically evaluate and compare the effects of the permeability of shields on bone augmentation in a rabbit calvarial model. MATERIALS AND METHODS Twelve adult male Japanese white rabbits were used for the study. Each received four titanium cylinders, which were placed into perforated slits made in the outer cortical bone of the calvaria and filled with autologous iliac bone. The tops of the cylinders were randomly covered with the following test materials: (1) uncovered (control), (2) a titanium mesh, (3) an expanded polytetrafluoroethylene (e-PTFE) membrane, or (4) a titanium plate. After 8 weeks, the animals were sacrificed, and ground sections were obtained for histomorphometric analysis. RESULTS There was no significant difference in augmented bone volume among all groups. However, the distribution of augmented bone in the cylinders differed among the groups. In the uncovered control, there was significantly less augmented bone in the upper third of the cylinder than in the middle or lower thirds. Findings were similar for the titanium mesh group and the e-PTFE membrane group, with significantly less augmented bone in the upper third than in the middle or lower thirds. In the titanium plate group, there was no significant difference in augmented bone among the upper, middle, and lower thirds. The differences among the upper, middle, and lower thirds of the cylinder were smaller in the order of titanium plate, e-PTFE membrane, titanium mesh, and uncovered control. CONCLUSION The use of low-permeability shields resulted in small differences in the distribution of bone structure in the present bone augmentation model.

PURPOSE To enhance the stability of titanium (Ti) implants using conditioned medium (CM) derived from rat bone marrow stromal cell (BMSC). MATERIALS AND METHODS BMSCs were isolated from rat femurs and grown in culture, and the culture medium was used as CM. The CM was immobilized on the surface of Ti implants with calcifying solution. The topology of the Ti implants after immobilization of CM was observed by scanning electron microscopy (SEM). The Ti-immobilized CM was analyzed by liquid chromatography with tandem mass spectrometry. The adhesiveness and the osteogenic differentiation of BMSCs grown on CM-coated discs were analyzed by reverse-transcription polymerase chain reaction. Ti implants with specimen-immobilized CM labeled with quantum dots (QDs) were placed into rat femurs. The localization of the CM was detected by in vivo imaging at 1, 7, 14, and 28 days after implantation. The removal torque test and histologic bone implant contact (BIC) were also analyzed. RESULTS Rat BMSC-CM was successfully immobilized on Ti implants. The immobilized CM contained about 2000 proteins, including collagen type I, bone sialoprotein, fibronectin, and vascular endothelial growth factor that are important in new bone formation. CM promoted cell adhesion and osteocalcin gene expression of rat BMSCs. The labeled CM remained associated with the Ti implant at 1, 7, 14, and 28 days postimplantation. The removal torque value and BIC of Ti implants with immobilized CM were higher than those of control implants on days 1, 7, and 14 after implantation. CONCLUSION Immobilized CM components on the surface of Ti implants promoted integration into bone during an early stage.

Purpose The objective of this pilot study was to histologically evaluate bone regeneration using a self-assembling peptide hydrogel scaffold with recombinant human bone morphogenetic protein-2 (rhBMP-2) in a rabbit calvaria model. Materials and methods Five adult New Zealand White rabbits were used for the study. Each received four titanium cylinders, which were placed into perforated slits made in the outer cortical bone of the calvaria. The cylinders were filled with the following test materials: (1) unfilled control; (2) rhBMP-2; (3) PuraMatrix (PM), a synthetic self-assembling peptide (RADA16-I) consisting of a 16-amino acid sequence and with a three-dimensional structure; and (4) PM/rhBMP-2. Each cylinder was covered with a titanium lid. After 8 weeks, the animals were sacrificed, and ground sections were obtained for histomorphometric analysis. Results Histomorphometric analysis showed that regenerated tissue in the cylinder with PM/rhBMP-2 was significantly increased compared to the empty control. The mean area values of regenerated tissue in the cylinders were 35.80% ± 10.35% (control), 47.94% ± 5.65% (rhBMP-2), 48.94% ± 11.33% (PM), and 58.06% ± 14.84% (PM/rhBMP-2). The mean area values of newly formed bone in the cylinders were 9.39% ± 4.34% (control), 14.03% ± 2.25% (rhBMP-2), 13.99% ± 2.15% (PM), and 16.61% ± 3.79% (PM/rhBMP-2). Neither rhBMP-2 nor PM alone significantly enhanced bone regeneration compared to the empty control cylinder. Conclusions PM with rhBMP-2 significantly enhanced bone regeneration on the bone augmentation model in a rabbit. PM promises to be a useful alternative synthetic material as a carrier for rhBMP-2 for bone regeneration.

トンネル覆工体と周辺地盤との間に免震層を形成する都市トンネルの免震構造では, トンネル軸方向のトンネル断面力を大きく軽減させ, とくにシールドトンネルのような柔構造では, 大きな免震効果を発揮することが確認されている. 免震層材料の物性としては, ヤング率が小さく, なおかつポアソン比が0.5に近いことが必要である. 本論文ではこのような物性を有する免震層材料として, シリコーン系材料を開発し, 物性試験ならびに大型実験土槽を用いた注入性確認実験を実施した. その結果, シリコーン系材料は, 物性, 施工性とも免震層材料として適切な材料であることが確認された.

Although a majority of the loach Misgurnus anguillicaudatus in Japan are diploid (2n = 50), natural tetraploids (4n = 100) have been found among specimens obtained from commercial suppliers. Eggs from diploid loach were genetically inactivated by UV-irradiating eggs. Eggs fertilized with spermatozoa from normal diploids resulted in inviable haploid offspring, while those fertilized with spermatozoa from natural tetraploids gave rise to viable diploid androgenetic individuals. Uniparental nature (all-paternal inheritance) in these androgenetic individuals was confirmed by chromosome observation and aspartate aminotransferase (AAT) allozyme genotypes.

In the ultrasonic atomization of metal nitrate solutions, the molar ratio of metal ions is changed between solution and mist. Small molar metal ions tend to be transferred to mist by ultrasonic wave acceleration, while large molar ions tend to remain in solution. As a result, metal ions can be separated by ultrasonic atomization. We show experimental data and propose a conceptual mechanism for the ultrasonic separation of metal ions.

Dimesitylsilylene, generated by photolysis of 2,2-dimesitylhexamethyltrisilane (1), reacts with epoxides to give dimesitylsilanone–epoxide adducts.

The reactions of silyl phenyl ketones with trialkyl phosphites and dialkyl sodiophosphonates gave dialkyl α-siloxybenzylphosphonates in good yields. The mechanism involves the migration of a silyl group from carbon to anionic oxygen. No deoxygenation of silyl ketone with trialkyl phosphite was observed.

Diiododimethylsilane reacts with various ketones in the presence of zinc to give the corresponding reductive condensation products in good yields.

Under neutral and mild conditions, silyl enol ethers are synthesized in good yields by the reactions of ketones or aldehydes with dimethylsilylene, which generated by the photolysis of dodecamethylcyclohexasilane.

Under neutral and mild conditions, silyl enol ethers are synthesized in good yields by the reactions of ketones or aldehydes with dimethylsilylene, which generated by the photolysis of dodecamethylcyclohexasilane.

Diiododimethylsilane reacts with various ketones in the presence of zinc to give the corresponding reductive condensation products in good yields.

An effective and convenient reduction of α-aryl alkanols has been developed with diiododimethylsilane to give the corresponding alkanes under mild conditions.

Photolysis of dodecamethylcyclohexasilane (1) in biacetyl, pentane-2,3-dione, bi-n-butyryl, bi-iso-butyryl, and 3,5-di-t-butyl-o-benzoquinone gave substituted 1,3-dioxa-2-silacyclopent-4-enes, the thermal and chemical properties of which are reported.

The reactions of silyl phenyl ketones with trialkyl phosphites and dialkyl sodiophosphonates gave dialkyl α-siloxybenzylphosphonates in good yields. The mechanism involves the migration of a silyl group from carbon to anionic oxygen. No deoxygenation of silyl ketone with trialkyl phosphite was observed.

Dimesitylsilylene, generated by photolysis of 2,2-dimesitylhexamethyltrisilane (1), reacts with epoxides to give dimesitylsilanone–epoxide adducts.