Yoshihide Mori

Acceleration of bone regeneration by local application of lithium: Wnt signal-mediated osteoblastogenesis and Wnt signal-independent suppression of osteoclastogenesis.

Inhibition of glycogen synthase kinase (GSK)-3 and the consequent activation of the Wnt/β-catenin signaling pathway have been reported to increase bone volume. To develop a novel pharmacotherapy for injured bone, we investigated whether GSK-3 inhibitor was effective in promoting bone formation. In in vitro experiments, we examined the effects of GSK-3 inhibitors LiCl and SB216763 on osteoblastogenesis of mesenchymal progenitor C3H10T1/2 cells and osteoclastogenesis of osteoclast precursor RAW-D cells. Both inhibitors promoted osteoblast differentiation, assessed by alkaline phosphatase activity and calcium deposition, stimulating the Wnt/β-catenin signaling pathway and thereby inducing Runx2. On the other hand, the GSK-3 inhibitors suppressed osteoclast differentiation, assessed by tartrate-resistant acid phosphatase staining and number of nuclei in the cells, reducing NFATc1 expression independently of the Wnt/β-catenin signaling pathway. In subsequently performed in vivo studies, we examined the effect of locally administered Li2CO3 on the recovery from a partial defect made on the rat tibia. Computerized tomography and bone histomorphometry showed that Li2CO3 accelerated bone regeneration in defect lesion with increased lamellar bone ratio compared with the controls. These results suggested that local application of lithium (or other GSK-3 inhibitors) might effectively facilitate recovery from bone injury by promoting osteoblastogenesis and inhibiting osteoclastogenesis.

Stimulation of splenocytes in C3H/HeJ mice with Porphyromonas gingivalis lipid A in comparison with enterobacterial lipid A.

Porphyromonas gingivalis 381 lipid A induced strong mitogenic response in splenic B cells separated from LPS-non-responsive C3H/HeJ mice as well as LPS-responsive C3H/HeN mice, by using a magnetic cell sorting system. The lipid A also exhibited mitogenic activity in splenic T cells. P. gingivalis lipid A induced lower production of interleukin-1 beta (IL-1 beta) in splenic macrophage cultures and exhibited a comparable IL-6 producing activity in splenic B cells of C3H/HeN mice as compared to Escherichia coli-type synthetic lipid A (compound 506) and monophosphoryl lipid A from Salmonella minnesota Re 595 (MLA). Furthermore, P. gingivalis lipid A, but not compound 506 nor MLA, induced low IL-1 beta and high IL-6 production in C3H/HeJ mice. C3H/HeJ T cells in response to P. gingivalis lipid A stimulation resulted in definite IL-2 mRNA and its production, whereas IL-4 response was scarcely active in both C3H/HeN and C3H/HeJ T cells. P. gingivalis lipid A increased tyrosine, serine/threonine phosphorylation of proteins with various major induced bands in splenic B cells of both C3H/HeN and C3H/HeJ mice. Thus, P. gingivalis lipid A stimulated the splenic immunocytes of C3H/HeJ as well as C3H/HeN mice.

T-box transcription factor Brachyury expression is correlated with epithelial-mesenchymal transition and lymph node metastasis in oral squamous cell carcinoma

The prognosis of patients with oral squamous cell carcinoma (SCC) is influenced by the presence of lymph node metastasis. Epithelial-mesenchymal transition (EMT), a process that involves events that convert adherent epithelial cells into individual migratory cells that can invade the extracellular matrix, is critical for cancer progression. Recently, the T-box transcription factor Brachyury was reported to promote EMT in human carcinoma cell lines. We analyzed the relationship between EMT (assessed by staining for E-cadherin and Vimentin) and the expression of Brachyury in association with lymph node metastasis in oral SCC. Oral SCC biopsy specimens (152 cases) were examined immunohistochemically for the expression of E-cadherin, Vimentin and Brachyury. Expression of Brachyury was correlated with EMT (p=0.035) and was significantly associated with lymph node and distant metastasis (p<0.05). Logistic regression analysis showed that Brachyury and EMT were predictive factors for lymph node metastasis (odds ratio 4.390 and 5.936, respectively) and that EMT was a predictive factor for distant metastases (odds ratio 11.786). Our findings present clinical evidence for an important role of Brachyury in EMT in oral SCC, and suggest that Brachyury and EMT patterns are useful prognostic markers.

Marsupialisation for keratocystic odontogenic tumours in the mandible: longitudinal image analysis of tumour size using 3D visualised CT scans

The purpose of this study was to determine how keratocystic odontogenic tumours (KCOTs) in the mandible are reduced during marsupialisation, and to predict the best time for secondary enucleation by analysing computed tomography (CT) images. 15 patients with KCOTs were treated with marsupialisation surgery, and 42 series of CT data taken during the marsupialisation process were analysed. CT data were reconstructed in three-dimensional (3D) images. The 3D images were used to measure the diameter and volume, and to analyse the changes that occurred after marsupialisation. Marsupialised KCOTs tended to be reduced equally towards the window in the tumour. The amount of volume reduction per day (V(r)) was reduced in proportion to the volume (V) with the formula V(r)=-0.0029×V. The formula manipulation for V was V=V(0)×e(-0.0029t) (t=duration after marsupialisaton (day)). The volume of marsupialised KCOTs was reduced by half over a 239 day cycle. These results demonstrate that the future shape of marsupialised mandibular KCOTs, under good control, could be predicted with significant accuracy using CT data. This prediction could decrease the prolonged marsupialisation state in patients with KCOTs.

Signaling pathway for adiponectin expression in adipocytes by osteocalcin.

In addition to providing skeletal support, the bone is an endocrine organ that produces osteocalcin, whose uncarboxylated form (GluOC) increases insulin secretion either directly or indirectly by promoting incretin secretion. We have now investigated the signaling pathway by which GluOC increases expression of adiponectin in adipocytes. Activation of its putative receptor GPRC6A by GluOC induced the intracellular accumulation of cAMP and consequent activation of protein kinase A (PKA) in differentiated 3T3-L1 adipocytes. It also induced phosphorylation of CREB (cAMP response element binding protein), but this effect appeared to be mediated indirectly by extracellular signal-regulated kinase (ERK) rather than directly by PKA, given that it was attenuated by the ERK signaling inhibitor U0126. Activated PKA also induced activation of the tyrosine kinase Src, the small GTPase Rap1, an upstream of ERK and CREB phosphorylation. Activated CREB up-regulated the expression of peroxisome proliferator-activated receptor γ (PPARγ), which in turn led to induction of adiponectin expression. Finally, intermittent oral administration of GluOC in mice reduced the size of gonadal white adipocytes as well as increased the expression of PPARγ and adiponectin in these cells. Our results have thus revealed the signaling pathway by which GluOC induces adiponectin expression in adipocytes.

Rapid three-dimensional measuring system for facial surface structure.

A noncontact three-dimensional measuring system (liquid crystal range finder system) is described. Three-dimensional facial surface data (more than 30,000 points) could be obtained in 1 second, and the resolution was approximately 0.4 mm. The reliability and repeatability of the results were validated with a calibrating apparatus and a highly accurate contact-type three-dimensional digitizer. Consequently, the average of the measurement errors on a facial plaster model was 0.3 mm. Repeatability in measuring human faces was approximately 0.3 mm. Therefore, the total error in measuring human faces was approximately 0.5 mm. Because of the shortness of measuring time, this system was capable of scanning faces of infants without the need for sedation. The output of the liquid crystal range finder was demonstrated on an infant with cleft lip. The surface points improved by cheiloplasty, and the residual deformities were observed clearly. This system was thought to be the most suitable apparatus for measuring faces of infants (especially infants with cleft lip) and enabled us to analyze facial surface structure both qualitatively and quantitatively.

Comparison Between Palatal Configurations in UCLP Infants with and without a Hotz Plate Until Four Years of Age

OBJECTIVE To evaluate the efficacy of presurgical orthopedic treatment three dimensionally, we previously developed a novel measuring system and described the efficacy of the treatment until 18 months of age. The aim of this study was to compare palatal configuration in complete unilateral cleft lip and palate (UCLP) infants fitted with a Hotz plate to those without it until four years of age using the same measuring system. PATIENTS Twenty complete UCLP infants were divided into two groups. A Hotz plate was used with 12 patients who first visited our clinic from January 1990 to March 1992 and was not used with an additional eight patients who first visited from April 1992 to July 1993. MAIN OUTCOME MEASURES Palatal casts taken from birth until four years of age were measured three dimensionally and were compared between the two groups. RESULTS AND CONCLUSIONS The width of the palate was larger in the group with a Hotz plate than in the group without it at four years of age. No difference was observed between the anteroposterior distance of the palate in the two groups at four years of age. Similarly, the alveolar arch form did not differ between the two groups. The degree of curvature of the palatal surface was smaller in the group with a Hotz plate than in the group without it. These data were similar to data obtained at 18 months of age.

Lesch-Nyhan syndrome: Successful prevention of lower lip ulceration caused by self-mutilation by use of mouth guard

Lesch-Nyhan syndrome (LNS) is a disorder caused by congenital absence of a purine metabolic enzyme, hypoxanthine guanine phosphoribosyl-transferase (HGPRT). This syndrome is characterized clinically by hyperuricemia and neurologic features including choreoathetoid spasticity, self-mutilation, and mental retardation. We report on a patient in whom self-mutilation of the lower lip was suppressed with the help of a mouth guard made from soft resin.

Acceleration of bone development and regeneration through the Wnt/β-catenin signaling pathway in mice heterozygously deficient for GSK-3β.

Glycogen synthase kinase (GSK)-3β plays an important role in osteoblastogenesis by regulating the Wnt/β-catenin signaling pathway. Therefore, we investigated whether GSK-3β deficiency affects bone development and regeneration using mice heterozygously deficient for GSK-3β (GSK-3β(+/-)). The amounts of β-catenin, c-Myc, cyclin D1, and runt-related transcription factor-2 (Runx2) in the bone marrow cells of GSK-3β(+/-) mice were significantly increased compared with those of wild-type mice, indicating that Wnt/β-catenin signals were enhanced in GSK-3β(+/-) mice. Microcomputed tomography of the distal femoral metaphyses demonstrated that the volumes of both the cortical and trabecular bones were increased in GSK-3β(+/-) mice compared with those in wild-type mice. Subsequently, to investigate the effect of GSK-3β deficiency on bone regeneration, we established a partial bone defect in the femur and observed new bone at 14 days after surgery. The volume and mineral density of the new bone were significantly higher in GSK-3β(+/-) mice than those in wild-type mice. These results suggest that bone formation and regeneration in vivo are accelerated by inhibition of GSK-3β, probably through activation of the Wnt/β-catenin signaling pathway.

Development of a 3-D measurement and evaluation system for facial forms with a liquid crystal range finder

A 3-D measurement and evaluation system for facial forms was developed with a liquid crystal range finder (LCRF). Its mechanical resolution was approximately/= 0.4 mm, and it was capable of measuring >30000 points from the entire facial surface in one second. An original program was developed to identify facial landmarks using not only linear distances, but also 3D-curvatures and discriminant analysis of the RGB data. With this program, the 3-D identification of anthropometrical points became possible with high accuracy. Due to the rapidity of the measuring apparatus and morphological evaluation system, it became possible to analyze the facial forms of infants such as cleft lip patients three dimensionally, without any sedation. Therefore, 97 normal infants (mean: 4.3 months of age) were measured and analyzed with this system. A cleft lip infant was measured and compared with the normal infants before and after cleft lip surgery, and the improved points and remaining problems were clearly recognized.