Masaaki Goto

The thermosensitive TRPV3 channel contributes to rapid wound healing in oral epithelia

The oral cavity provides an entrance to the alimentary tract to serve as a protective barrier against harmful environmental stimuli. The oral mucosa is susceptible to injury because of its location; nonetheless, it has faster wound healing than the skin and less scar formation. However, the molecular pathways regulating this wound healing are unclear. Here, we show that transient receptor potential vanilloid 3 (TRPV3), a thermosensitive Ca2+‐permeable channel, is more highly expressed in murine oral epithelia than in the skin by quantitative RT‐PCR. We found that temperatures above 33°C activated TRPV3 and promoted oral epithelial cell proliferation. The proliferation rate in the oral epithelia of TRPV3 knockout (TRPV3KO) mice was less than that of wild‐type (WT) mice. We investigated the contribution of TRPV3 to wound healing using a molar tooth extraction model and found that oral wound closure was delayed in TRPV3KO mice compared with that in WT mice. TRPV3 mRNA was up‐regulated in wounded tissues, suggesting that TRPV3 may contribute to oral wound repair. We identified TRPV3 as an essential receptor in heat‐induced oral epithelia proliferation and wound healing. Our findings suggest that TRPV3 activation could be a potential therapeutic target for wound healing in skin and oral mucosa.—Aijima, R., Wang, B., Takao, T., Mihara, H., Kashio, M., Ohsaki, Y., Zhang, J.‐Q., Mizuno, A., Suzuki, M., Yamashita, Y., Masuko, S., Goto, M., Tominaga, M., Kido, M. A., The thermosensitive TRPV3 channel contributes to rapid wound healing in oral epithelia. FASEB J. 29, 182–192 (2015). www.fasebj.org

Development of a novel PCR method to comprehensively analyze salivary bacterial flora and its application to patients with odontogenic infections

OBJECTIVE The objective of this study was to develop a novel polymerase chain reaction (PCR) method to comprehensively analyze salivary bacterial flora. STUDY DESIGN The bacterial flora in the saliva of 10 healthy persons and 11 patients with odontogenic infections were examined using a DNA extraction method with a high level of cell destruction efficiency and a novel universal primer set to amplify approximately 580 bp of the 16S rDNA sequence. RESULTS Streptococcus (54.5%), Neisseria (14.7%), Actinomyces (8.4%), Gemella (4.1%), Granulicatella (3.8%), and Prevotella (1.4%) were dominant in a total of 1655 clones examined from the saliva of the healthy subjects. The dominant genera differed among the patients with odontogenic infections (a total of 823 clones) and were entirely different from those of the healthy subjects. CONCLUSION This novel comprehensive salivary bacterial flora analysis method may be a useful supportive method to identify causative agents of odontogenic infections.

Sequential expression of endothelial nitric oxide synthase, inducible nitric oxide synthase, and nitrotyrosine in odontoblasts and pulp cells during dentin repair after tooth preparation in rat molars.

Nitric oxide (NO) stimulates osteoblast differentiation, but whether NO contributes to odontoblast differentiation during dentin repair is unknown. By using reverse transcription/polymerase chain reaction and immunostaining, we investigated the gene expression and/or immunolocalization of endothelial NO synthase (eNOS), inducible NOS (iNOS), and nitrotyrosine (a biomarker for NO-derived peroxinitrite), and alkaline phosphatase (ALP) and osteocalcin (early and terminal differentiation markers of odontoblasts, respectively) in dental pulp tissue after rat tooth preparation. At the early stage (1–3 days) post-preparation, markedly increased expression of iNOS and nitrotyrosine was found in odontoblasts and pulp cells beneath the cavity, whereas eNOS expression was significantly decreased. ALP mRNA expression was significantly increased after 1 day but decreased after 3 days, whereas ALP activity was weak in the dentin-pulp interface under the cavity after 1 day but strong after 3 days. Osteocalcin mRNA expression was significantly increased at this stage. At 7 days post-preparation, tertiary dentin was formed under the cavity. All the molecules studied were expressed at control levels in odontoblasts/pulp cells beneath the cavity. These findings show that abundant NO is released from odontoblasts and pulp cells at an early stage after tooth preparation and indicate that, after tooth preparation, the up-regulation of iNOS and nitrotyrosine in odontoblasts is synchronized with increased cellular expression of ALP and osteocalcin. Therefore, the NO synthesized by iNOS after tooth preparation probably participates in regulating odontoblast differentiation during tertiary dentinogenesis.

TRPV2 expression in rat oral mucosa

The oral mucosa is a highly specialised, stratified epithelium that confers protection from infection and physical, chemical and thermal stimuli. The non-keratinised junctional epithelium surrounds each tooth like a collar and is easily attacked by foreign substances from the oral sulcus. We found that TRPV2, a temperature-gated channel, is highly expressed in junctional epithelial cells, but not in oral sulcular epithelial cells or oral epithelial cells. Dual or triple immunolabelling with immunocompetent cell markers also revealed TRPV2 expression in Langerhans cells and in dendritic cells and macrophages. Electron microscopy disclosed TRPV2 immunoreactivity in the unmyelinated and thinly myelinated axons within the connective tissue underlying the epithelium. TRPV2 labelling was also observed in venule endothelial cells. The electron-dense immunoreaction in junctional epithelial cells, macrophages and neural axons occurred on the plasma membrane, on invaginations of the plasma membrane and in vesicular structures. Because TRPV2 has been shown to respond to temperature, hypotonicity and mechanical stimuli, gingival cells expressing TRPV2 may act as sensor cells, detecting changes in the physical and chemical environment, and may play a role in subsequent defence mechanisms.

Redox Characteristics of Thiol Compounds Using Radicals Produced by Water Vapor Radio Frequency Discharge

The redox reaction between cystein and cystine is observed using radicals produced in water vapor plasma for the control of plant growth. Cystein is oxidized to cystine using the OH radical in the higher-pressure regime and cystine is reduced to cystein by the H radical generated in the lower-pressure regime. Also, the oxidative stress reaction of plants is observed when water vapor plasma is irradiated onto seeds of plants such as radish sprouts. The mechanism of the control of plant growth is explained by the change in thiol compound quantity of the plant cells induced by the radical reaction.

A System for International Telemedicine through Integrated Synchronous/Asynchronous Collaboration

To support international medical collaboration activities carried out among Japan, Sri Lanka and other countries in Asia, we have been developing a collaboration system, which incorporates synchronous and asynchronous collaboration paradigms through network-effective persistent information sharing. The designed system facilitates synchronous collaborative work on maxillo-facial cases through real-time high-quality image delivery and by bringing the system database objects to a shared-workspace. The asynchronous activities are supported through a web based collaborative environment that enables both activity-centric and object-centric navigation of collaboration contents incorporated with email notifications of the system updates. Multimedia records of synchronous sessions are posted to the system database for later reviewing. Geographically dispersed groups experiencing different scales of network heterogeneities are served by a distributed application level multicast overlay and an adaptive multimedia delivery mechanism. The designed collaboration system also features several useful collaboration tools, user friendly GUI and ubiquitous connectivity.

Case of pediatric acute promyelocytic leukemia presenting as extramedullary tumor of the mandible

Acute promyelocytic leukemia (APL) is a malignant subtype of acute myeloid leukemia caused by the PML‐retinoic acid receptor (RAR)α fusion gene. APL may be discovered in adulthood and diagnosed after spontaneous gingival bleeding or difficulty in hemostasis after oral surgery such as tooth extraction. However, APL is extremely rare in children.

Modification of hydroxyapatite crystallization using CO2 laser

To remineralize the dentine surface viz. improve the micro-hardness and acid-resistance of the surface of teeth IR laser application was concerned in this study. Experimental aims are concentrating to investigate changes of hydroxyapatite crystal structure before and after laser irradiation with characteristic absorption wavelength region around 10.6 μ m. As a preliminary study for FEL application in biological field, the results we have got with the 10.6 μ m irradiation demonstrate that the capability of FEL of precisely deliver energy over a wide band of IR wavelength, offering control over surface modification, made it an attractive tool for further ameliorating of hydroxyapatite crystallization.

A groupware design for supporting international medical collaboration over the internet

A groupware that integrates synchronous and asynchronous collaboration paradigms is developed to support international medical collaboration activities carried out among Japan, Sri Lanka and other countries in Asia. Synchronous medical collaboration activities are facilitated through high-quality image transmission and through an interactive shared-workspace. A web based asynchronous collaboration environment facilitates file uploading, editing and reviewing functions. Provisions such as multi-stream session recording, enhanced object linkage of collaboration contents, and persistent data sharing, harness the integrated collaborative environment. Adaptive M-JPEG transmission, application level multicasting and mirrored database architecture enables efficient data transmission among heterogeneous groups connected through wide range of network channels.

Three-dimensional evaluation of healing joint morphology after closed treatment of condylar fractures

Closed treatment for condylar fractures has long been widely accepted. With closed treatment, the deviated bone fragments heal in their new positions, and this may subsequently cause a range of functional impairments. The association between healing morphology and post-treatment functional impairment is unclear. In this study, computed tomography images of 26 patients (35 sides) who had undergone closed treatment for condylar fractures were used to perform a comparative investigation of three-dimensional (3D) bone morphology before and after treatment. As a result, the morphology of the condylar process after treatment was classified into four different patterns: unchanged, spherical, L-shaped, and detached. In terms of the association between fracture types and healing morphology, fractures of the condylar head healed in the spherical pattern, simple fractures of the condylar neck healed in the spherical or L-shaped pattern, and comminuted fractures of the condylar neck healed in the spherical, L-shaped, or detached pattern. The association between mandibular deviation and healing morphology was also investigated, and it was found that deviation was greater for the spherical and detached patterns than for the L-shaped pattern. The present findings indicate that 3D evaluation of the fractured condylar process is required to elucidate the association with functional impairment after healing.